Document LKry7njZ8xL1DLQKwRqLG5Zog

PLAINTIFF'S EXHIBIT UC-106 LA O -tt *T\ (n United States Patent Office 3,485,790 Patented Dec. 23t 1969 4 2 acrylate copolymer, ethyl acrylate-methyl acrylale-vinyl 3.4S5.790 acetate copolymer, ethyl acrylate-acrylonitrile copolymer, nu.r.n ESTER-CONT \INIKC POLYMERS George II. Potter. SI. Albans, end Clyde J. Whitworth. Jr_ ?d fv>lhnn L. Zutty, Charleston. W. Va,, issicnors 2-ethylhcxy] acrylate-acrylonitrile-ethyl acrylate copoly mer, ethyl arrylale-dimethyl maleale-acrylonitrlk copoly- lo I'nion Tiirhidt Corporation, a corporation of New . mer. ethyl acrylaie-octyWecyl methacrylate-acrylonitrile \orW copolymer, methyl mcthacrylate-styrene-acrylonitrile co No Drawing. Filed Jonc 29, 19(5, Ser. No. 468,155 polymer, ethyl acrylale-vinyl chloride-acrylonitrile co lot- CL COSf 45/04, 29/24 polymer, butyl acrylaie-vinylidene chloride copolymer, 2- VS. CL 2(0--41 12 Claims methoxyethyl acrylate-acrylonitrile copolymer, 2-butoxy- 10 ethyl acrylate-acrylonitrile copolymer, and the like. Many other ester-containing polymers arc useful. For instance, ARSTRACT OF TIIF. DISCLOSURE elhylene-hutyl maleate copolymer, ethylene-butyl furna- Improved filled polymers are obtained by heating a mix ture of an ester-containing polymer, a finely divided inor ganic filler containing chemically bound water and an acidic or basic catalyst for a period of time sufficient to IS rate copolymer, and the like are useful in (he invention. The preferred thermoplastic ester-containing polymers are copolymers of ethylene and one or more of vinyl acetate, alkyl acrylates wherein preferably the alkyl has up to 18 carbon atoms, alkyl methacrylates wherein preferably the effect reaction between the polymer and the filler. alkyl has up to 18 carbon atoms, and alky] maleslet or fumarates wherein preferably the alkyl has up to 18 car- 80 bon atoms. Normally the thermoplastic ester-containing The invention relates to a process for producing im polymer will contain at least about S weight percent of proved filled polymers and to the improved filled poly the ester-containing monomer (in polymerized form), and meric compositions that are produced thereby. In a par preferably at least 15 weight percent of the ester-contain ticular aspect, the invention relates to a process which ing monomer, percentages being based upon weight of comprises heating a mixture of an ester-containing poly 85 polymer. The molecular weight of the ester-containing mer. a filler, and a catalyst. In another aspect, the inven polymer is such that the polymer is normally solid at tion relates to the compositions that are produced by the room temperature fi.e.. about 23* C.). The molecular process of the invention. weights of many of the thermoplastic ester-containing Ester-containing polymers such as ethylene-vinyl acetate polymers that are useful in (he invention can be further copolymer or ethylene-ethyl acrylate copolymer can be 30 characterized by Melt Index as determined by tbe proce improved in heat resistance, stiffness, and other properties dure described in ASTM D-I238-57T. Many of the poly by adding certain reactive fillers such as colloidal silica to mers will have Melt Index values in the range of from the polymers. The present invention is based upon the about 0.1 lo about 400, and preferably fu>m about 0.5 to discovery that properties of esleh-containing polvmess that about 100. contain reactive fillers inn be further improved hy em 35 Many oihcr polymers can he employed in conjunction ptying a catalyst when the filler is added to the polymer. with the thermoplastic ester-containing polymer. Specific Accordingly, the process of the invention comprises mix illusiiative examples include polyethylene, polypropylene, ing an ester-containing rolymer, a reactive filler, and a ethylene-propylene copolymer, poly (vinyl chloride), vinyl catalyst, for a period of time and at a temperature suffici chloride-acrylonitrile copolymer, polyacrylonitrile, etbyl- ent to effect a reaction between said polymer and said *n ene-acrylonitrile copolymer, polyamides such as nylon fi, filler, and recovering the filled polymeric composition pro nylon 6/6. and the like, polyethylene terephlhalale and duced thereby. other polyesters, the polybydroxy ether produced by re The improved, filled polymeric compositions of the in acting equimolar proportions of 3-chloro-l,2-epoxypro- vention have one or more of the following characteristics: pane and the divodmm salt of 2,2-bis(4-bydroxypbenyI)- (a) Improved high temperature resistance. to propane, and the like. (b) Improved water and organic solvent resistance, The filler that is employed in the invention can be one fc) Improved electrical properties. or more of colloidal silica, certain clays, certain aluminas, Id) Higher lensile strength, and the 1i):e. asbestos, and the like. The polymers that are employed in the invention are The silica ibat is employed in the invention is a finely the ester-containing thermoplstic polymers wherein the divided silica having a surface layer of hydroxyl groups. ester group is in a side group that is bonded to a polymeric The commercially available silicas (hat are useful in the chain composed of carbon-to-carhon bonds. Among the invention are known to the an as colloidal silicas. Such useful ester-containing polymers are those that contain po silicas are composed of panicles that have their maxi lymerized vinyl acetate. For example, vinyl acetate homo mum dimension in the range of from about 0.001 micron polymers and vinyl acetate copolymers with one or more 5 to about 0.1 micron, and have a specific surface area of comonomers that are polymerizable alone wiih vinyl ace at least about 100 square meters per gram, and preferably tate are useful. Among the vinyl acetate polymers contem at least about 150 square meters per gram. The specific plated are vinyl acetate homopolymer, vinyl accrete-ethylene copolvmer. vinyl chloride-vinyi aerate c'r-o'ymer. surface area can b: measured by nitrogen adsorption in accordance with the method described in the article **A vinyl chlmide-vinyl acetate-vinyl alcohol conob mer. r, New Method for Measuring Surface Areas of Finely Di vinyl chloride-vinyl acetate-maleic anhydride enrolvmer, styrcne-sipvl acetate copolymer, vinvl chiorid-.vinylidene vided Materials and for Determining the Size of Particles" by P. H. Emmett, ir. the publication "Symposium On New chloride-vim 1 acetate copolymer, vinyl areta't-acrsloni- Methods for Parrirlc Size Determination in the Sub- trile copolymer, and the lil.e. Vinyl acetate t> 'y:::tt\ that Sieve R ings." puhii-hed hy the American Society For deserve particular mention are vinyl acetate hnmopoly- to Testing Materials. Mar. 4. 1941. mer. ethylene-vinyl acetate copolymer and vinvl chloride- The individual silica particles, which have their greatest vinyl acetate copolymer. Ethylene-vinyl acetate copolymrrs are preferred. dimension in the rarer of from about 0.001 to about 0.1 micron, can be in the form of aggregates having a much The ester-containing thermoplastic polymer can he a larger dimension. These aggregates are broken down when homopulymer or a copolymer of an acrylic or a meth- 7 the silica is mixed with the other materials to form the acrylic acid ester. Specific illustrative examples include compositions of the invention. Tbe surface layer of hy ethylene-ethyl acrylate copolymers, ethylene-methyl metb- droxyl groups on ihejsilica particles are chemically bound A i uo33 a,485,790 4 the silica. There it thus provided a monomoleeular elude ethyl dihydrogen phosphite, decyl dihydiogen phos -yer of tilanol groups on the surface of the silica par* tides. The preparation of finely divided silica having a sur phite. phenyl dihydrogen phosphite, scaiyl dihydrogen phosphite, diethyl hydiocen phosphite, di(2-uh>ihexyl) hydrogen phosphite, diphenyl hydrogen phosphite, di- face layer of hydroxyl groups can be by various .methods ft benryl hyd.ngen phosphite, dilolyl hydrogen phoirhite. di known to the art. For instance, any of the fol`owing three cyclohexyl hydrogen phosphite. Irimcihyl phosphite, iri- procedures can be used to produce the silica that is used ethyl phosphite, tripiopyl phosphite. Uiisopropyl phos in the invention: (1) A silica aerogel may be formed by gelling silicic phite. tributyl phosphite, triisobutyl phosphite, tripentyl phosphite, Iriheptyl phosphite, trihtxyl phosphite, trioctyl acid in an alcohol-water solution and then converting the to phosphite, Irinnnyl phosphite, Iridccyl phosphite, triiso- gel to an aerogel. This may be carried out by replacing decyl phosphite, iritlod'-cyl rhosphiie. triocladecyl phos most of the water of the gel with alcohol, heating the gel in an autoclave above the critical temperature of alcohol phite, iiirydohcxy! phosphite, diethyl butyl phosphite, tri.benzyl phosphite, triphenyl phosphite, tri-1-naphthyl phos so that there is no meniscus between the liquid and gas phite tri-2-naphlhyl phosphite, tri-l-amhryl phosphite, phases and venting the vapors. In this way the liquid phase 13 phenyl dimethyl phosphite, phenyl diethyl phosphite, is removed without subjecting the gelled structure to the phenyl dipropyl phosphite, phenyl dibutyl phosphite, compressive forces due to the surface tension of the liquid- phenyl dipntyl phosphite, phenyl diheptyl phosphite, gas interface. A pulverized light fluffy powder of silica phenyl dihexyl phosphite, phenyl dioctyi phosphite, phen- particles may then be formed by pulverizing the dry .yl dinonyl phosphite, phenyl didecyl phosphite, phenyl aerogel. 20 triisodecyl phosphite, phenyl didodecyl phosphite, 1-naph- (2) Colloidal silicas may be prepared by vaporizing thyl didecyl phosphite, diphenyl methyl phosphite, diphen silicon dioxide at high temperature or producing silicon- yl ethyl phosphite, diphenyl propyl phosphite, diphenyl containing vapor by burning ethyl silicate or silicon tetra butyl phosphite, diphenyl isohuty! phosphite, diphenyl chloride and thereafter collecting the "silica fume." pentyl phosphite, diphenyl heptyl phosphite, diphenyl (3) Still another technique of preparing colloidal silicas "5 hexyl phosphite, diphenyl octyl phosphite, diphenyl non- is to precipitate silica from aqueous solution in such form yl phosphite, diphenyl decyl phosphite, diphenyl isndecyl that it can be dried to give a fine powder. phosphite, diphenyl dodccyl phosphite, di-l-anthryl ethyl Additional descriptions of the nature and production of phosphite, uieinylene diphosphitc, i.e., the compound finely divided silica having a surface layer of hydroxyl having the formula groups can be found in the laterature. One such source SO is "The Colloid Chemistry of Silica and Silicates" by O-CIltCIlr-O Ralph K. Her (published in 1955). Certain clays are useful as fillers in the invention. The y--O--ClltCIlr-O-P Nj-CltjCllr-O^ ' vs that are useful in the invention are the colloidal des having a specific surface area of at least about ISO 3.1 tripropylcne diphntphile. trihutylrne diphosph'te, and tbe square meters per gram and which have an average par ticle size of less than 1 micron. As is well known in the art, the exact composition of clays vary depending upon like. Many of the phosphUes that can be employed in the invention can be represented by Formula 1: their aource, but they are normally hydrated silicates of aduminum, magnesium, or iron or mixtures thereof. The 40 I OR preferred clays are those that are predominantly hy drated magnesium aluminum silicates. Hydrated aluminum oxide having a particle size sucb that the largest dimension is less than about 1 micron is wherein each R individually can be hydrogen, alkyl, aryl, useful as a filler in the invention. 4.1 alkaryl, aralkyl, cycloalkyl, alkylene phosphite, and the Another filler that is useful in the invention is asbestos, like, provided that at least one R represents an organic preferably chrysotile asbestos. group. Preferably, all three R groups represent organic Tbe preferred filler for use in the invention is colloidal groups. Normally, R will represent a group having not silica. more than about 18 carbon atoms. The discussion above points out that there are many 10 The catalyst can also be a titanate ester. Specific illus different fillers that can be employed in the invention. trative examples include letramethyl titanate, tetraethyl The one feature that all of these fillers have in common, titanate, tetraisopropyl liunate, tetrabiltyl titanate, letra- apart from small panicle size, is that they are inorganic octyl titanate, tetra(2-elhyl-],3-hexanediol) titanate, and compositions that contain chemically bound water. Ap other alkyl titanate esters wherein the alkyl groups have parently, hydroxyl groups provided by the water react aw up to 18 carbon atoms. with the ester groups of the ester-containing polymer to Many organic tin compounds can be employed in the thereby form a bond from the filler to the polymer. Chem invention. Among the organic tin compounds that car. be ically bound water is contrasted with moisture in that used are the stannous salts of alkanoic acids such as chemically bound water is not released until the filler is stannous octoate. stannous acetate, stannous laurate, stan healed to a temperature above about 500*-600* C., while 00 nous stearate, and the like. Also, the organotin com moisture is driven off at the boiling point of water. pounds can be employed. Such compounds have at least The catalysts which have been found to promote the one direct carbon-to-tin bond, and preferably, at least one reaction between the filler and the thermoplastic ester- bond to oxygen, sulfur, nitrogen, halogen, phosphorus, or containing polymer are the non-netitr.;l compositions, hydrogen. Specific illustrative examples of useful orgr.no- i.e.. the acids and the bases. Any snnstanct which is an 01 tin compounds include the following compositions: arid or a base under either the hronsted-l owry theory (A) Tin compounds having four carbon to tin bonds (proton-transfer system) or the Lewis theory fdectron- such as letramethyltin. letraethyltin, tetrapropyliin. letra- :r system I can be employed as a CBtalvs! ir. the inven- butvliin, leiraociyltin, teiralauryltin. tetrabenzyltin. tei- .. Among the useful catalysts ore found the phosphite rakis(2-phenylethyl (tin, tetrapbenyltin, tetraparatolyltin, the tiianate esters, certain organic tin compounds, TO tetravinyltin, telraallyltin, tctrachloromelhylun, letra- proton acids (i.e.. compounds that contain an acidic hy drogen atom), amines, alkali metal hydro'ides and alit- methanesulfonylmetbvltin, tetre-para-metboxy-phenyliin, tetra-paraniirophenyltin. as well as unsymmetrica! com oxides, ali.aiint earth metal hydroxides and iilkoxides. pounds as exemplified by 2-ryanocthyl-trihutyliin. dihutyl- anJ many other classes of compounds that arc either diphcnvliin and various addition products of alkyl, aryl acids or hzses. Specific illustrator phosphite esters in- 73 and aralkyltin hydtides with unsniuraied organic coat- 3,485,790 pound* Mich as acrylonitrile, nllyl cyanide, croionitrile. gnno-tin compounds containing carbon to tin bonds and acrylamide, meihyl acrylate, ally! alcohol, acroleindielhyl pteferably also bonds, c.g., those having repeating ocei.nl. vinyl acciale, styrene, and the like; _ (B) Tin compounds having n carbon to tin bonds and 4- bond* front tin to halogen or hydrogen atoms or hydroxyl groups in which n is an integer in the range ot from 1 to 3, such as Irimelhyltin chloride. tributyltinchloride, trioctyllin chloride, triphenyllin chloride, tri- R I Ml - I H groups, dimers and trimers of (RSnY), and (he like in methyltin bromide, tributyliin fluoride, triallyltin chloride, which the R's may be alkyl, aryl or aralkyl radicals and tributyliin hydride, triphenyllin hydride, Irimelhyltin hy 10 <he Vs are chalcogens, as well as many other organo-lin droxide, tributyliin hydroxide, dimeihyllin dichloride, di- compounds heretofore proposed as heat and light stabiliz butyiiin dichloride, dioctyllin dicbloride, bis(2-phenyl- ers for chlorinated polymers and available commercially ethyl)tin dichloride, diphenyltin dichloride, divinyltin di for this purpose. chloride, diallyltin dibromide, diillyltin diiodide, dibutyliin The preferred tin compounds are the stannous alkano- difluoride, bis(carboethoxymethyl)tip diiodide, bis(l,3-di- is ates and the dislkyltin compounds that also have two leiopemane)tin dichloride, dibutyliin dihydride, butyltin valence bonds from tin to oxygen. trichloride and ociyliin trichloride; The catalyst employed in the invention can also be an (C) Tin compounds having two carbon to tin bonds amine or an amine derivative. Specific illustrative ex and a double bond from tin to oxygen or sulfur, such as amples include tertiary amines such as 1,4-diszabicyclo dimethyltin oxide, dielhyltin oxide, dibutyliin oxide, di- 0 |2.2.2)oetane, bisr2-(N,N-dimethylamino)etbyl] ether, octyltin oxide, diiauryliin oxide, diphenyltin oxide and tricthylxmine. and the like, strong bases such as guanidine, diallyltin oxide, all prepared by hydrolysis of the corre quaternary ammonium compounds, and the like. The pre sponding dihalides, as well as bis-2-pbenyletbyltin oxide, ferred amines are the tertiary amines. [HOOC(CH,),],SnO Proton acids are also useful as catalysts in the inven23 tion. Specific illustrative examples include benzene-sul tCHjOCHa(CHxOCHj)s.jCHj]jSnO fonic acid, toluene sulfonic acid, phosphoric acid, sulfuric JCH,OCHI(CH,OCH,)1.,CH,0(CH,)llISnO acid, hydrogen chloride, and the like. The arylsulfonic acids are the preferred proton acids. and dibutyliin sulfide, the i's being whole integers; Other acids that are useful as catalysts in the inven- (D) Tin compounds having n carbon to tin bonds and go lion include boron trifluoride (usually as a complex with 4-n bonds from tin to oxygen, sulfur, nitrogen or phos- diethyl ether or an amine), titanium tetrachloride, ferric pborus linking organic radicals, n being an integer from 1 chloride, stannous chloride, stannic chloride, aluminum to 3, such as tributyltin methoxide, tributyliin butoxide, chloride, and the like. tributyliin acetate, tributyltin N-piperazinylthiocarbonyl- A further class of useful calalysts includes the alkali mercaptide, tributyltin phosphorus dibutoxide [prepared 35 meial_and alkaline earth metal alkoxides and hydroxides, as indicated immediately helow: Specific illustrative examples of these materials include stc.n,0),r 4 rcu --. JC1I,0)1*CI sodium methoxide, sodium ethoxide, sodium isopropoxide, pojawitm ethoxide, potz'sium butoxide, magnesium metb- (C.ll.liEnCl 4- 2N ----- (C.II,) BuNa 4 NaC'l oxide, calcium ethoxide, barium propoxide, lithium meth- vn. (C.N,)iSnK + (CdliQlit'Cl ---- 40 oxide, sodium hydroxide, potassium hydroxide, lithium hydroxide, calcium hydroxide, magnesium hydroxide, and (C.TI.)iSuP (OC.lt.'. 4- NaCl the like. The alkali metal alkoxides are preferred. The process of the invention comprises heating a mix dibutyltin dibutoxide, ture of an ester-containing polymer, a filler, and a eata- (CH()jSn [ OCHj (CHjOCHa)*.jCHjCH,l a 45 lyst for a period of time sufficient to effect reaction be dibutyl bis(0-aeetylcelonyl)tin, dibutyliin bis(octyl ma- tween the polymer and the filler. The proportion of the components can vary widely. For example, the filler can leate), dibutyltin bis(tbiododecoxide), dibutyliin bis (octyl thiogiycolate), dibutyliin bis(N-morpholinylcarbonylmetbX>1 m*cearcpaipitdidee)),, ddiibbuuttyyll!tiinn ddibeinozeneesnulfoznaeminne, deimselhuyl-i60 be employed in quantities of at least about 1 weight per cent, and preferably at least about 10 weight percent, based on weight of filler plus polymer. More preferred tin d.aceiate, dieihyli.n d.acetate d.butylt.n d.aceta e. dt- propor1iom of fi,,er are found J~,hin the ran Pof from ^k ''l? '^'8Ce*^C' 13jL .VfirC=I'invl'ihiotiar' dibutyliin maleale dibutyliin bisfN.piperaznyl.h.ocar- mbout 20 t0 abou< 70 Pcenl. based on weight of , ,us fiIler ,, rare ^ ^ fi|Jer W|,,ebe bonylmercapt.de), d.octylt.n b.s(N-p.peraz.nylth,ocarbOn- employed in proponions of mt>re lhan abou, 80 ylmercapiide), octyllin tris(thiobutoxide), butyltin tri acetate, methylstannonic acid, ethylstxnnonic acid, butylstanmmic acid, octylstannonic acid, 6i percent, based on weight of polymer plus filler. The catalyst is employed in catalytic quantities suffi cient to promote the reaction between polymer and filler. HOOC(CH*)-SnOOH, <CH,),N(CH,)SnOOH For example, useful proponions of catalyst are found in CHjOCHjfCHjOCHjl^jCHjSnOOH the range of from about 0.1 weight percent, and lower, 60 to about 8 weight percent, and higher, based on weight of and polymer plus filler. Preferred proponions are found in CH;OCHj(CH-OCHj),.jCHjO(CHj)SnOOH the range of from about 0.3 to about 5 weight percent of catalyst, based on weight of polymer plus filler. in which the x's are positive integers. The process of the invention is carried out at an ele- (E)' Pol' stannic commun'ds'having carbon t.. tin bonds " v,ed temperature for a period of time sufficient to effect and preferably also bonds from tin to halogen. hydrogen, oxygen. <u!fur, nitrogen or phosphorus, such as reaction between the polymer and the filler. For example, a reaction temperature in excess of about 90* C., and preferably Jd excess of about 110* C., is useful. Nor HOOSn(CKj)SnOOH mally. the temperature will not be in excess of about and HCOSnCH:(CHjOCH-),CHjSnOOH ;n 250* C. Reaction times of from about 5 minutes tq\ 3 hours or more are useful. Preferred times are found' within tbe range of from about 10 minutes to about the x's being pns::ive integers. bis-trime*hy!tin. fci`-tri- 1 hour. phenyltir.. rii-trii-utyi distannoxane. dibutyliin basic lau- The process of the invention can be carried out by rate, dibu:v;;:n basic bexoxide and other polymeric or- 75 mixing tbe polymer, filler, and catalyst in a beaicd mill. 3,485,7!*) 78 Ranhury mixer, extruder, or the like, in order to insure TPP--Triphenyl phosphite. iim:iie mixing of the components. The mixture can then-' DPPD--Diphenyl peniaerylhritol diphotphile. -<e molded, or the like, if desired, in order to pro^ace D-22--DibutyHin dilaurate. the finished product. D-14--DibutyHin Uurate maleate. The process of the invention is useful for producing D-l 5--DibutyHin dimaleate. molded articles having wide utility. In addition, the pros* 6 PTSA--p-Toluene sulfonic acid. ess of the invention can be employed to produce extruded DABCO---1,4-diazabicyc)ol 2.2.2 ]octanc. coatings and other materials whose utility is enhanced BF,--Boron viftuoride-elherate. by the improved properties that are the results of the NiOCH,--Sodium methoxide. practice of the invention. CaO--Calcium oxide. The examples which follow illustrate various aspects *** Polymers: of the invention. Polymer A--Elhylene/viny) acetate copolymer (Melt EXAMPLES 1-34 To a 6*' x 12" two-roll mill that was maintained at 120*-130* C., there was added 150 prams of Polymer A Index=22) containing 28 weight percent vinyl acetate. Polymer B--Etbylene /ethyl acrylate copolymer (Melt Indexc2) containing 18 weight percent (an ethylene-vinyl acetate copolymer which has a Melt Index of 22 and which contains 28 weight percent vinyl acetate) and 1.5 grams of stearic acid (as a mill lubri cant). To this polymer, there was added over a 5 to 10 .. minute period 150 grams of Silica A (a colloidal silica ethyl acrylate. Polymer C--Medium molecular weight poly(vinyl acetate). Polymer D--Ethylene/butyl maleate copolymer (Melt Index=*24.0, weight percent butyl male- having an ultimate panicle size of about 0.025 micron and having a specific surface area of about 110 square meters/gram). After the silica had been added, 5 milli liters of tetraisopropyl titanate was added. The mixture was then milled for 15 minutes at I20*-140* C. The atess 30.3). Polymer E--Ethylene/butyl fumarate copolymer (Melt Index=8.9, weight percent butyl fumarate=29.1). mixture was then sheeted off and a portion was molded Representative properties of the compositions arc dis at 185* C. and about 5000 p.s.i. for 15 minutes. The played in Table 1, which follows. TAIILE I.--l-ATALVWTS HIK TIIK J.vrKIIAi'TIUN OF HEACTIVE FlI.LEItE WiTII ESTKK-cttKTAININU POLYMERS Etamplt Calatjmt i'uL. 4 |r*i vnl by Hi. Polymer Silica Paretnt Filler, Polymer tirrucnl Insoluble in by WL Toluene 1 Motlulin TentUe hntnt Btlltnas 1*0* C., BtnufUi, Elonrv- R.T. pa.I. pjJ. tioa 1............ .. Tll'T......................... 7........... 34...................... . . .. T1PT........................... tiit..................... TJI'T........................... I f. A................. I f. 1 ................ I.H ............ I.f. itrjft. AfC .. ft............... .. TIFT........................... e........... ..TIFT........................... *.3 IV.'X.AIC... ,ti ru/jn, a/C... 7............... .. OUT............................ 1.4. A.................. 16.......................... .. .. OUT............................ EOF............................. 2 1 W30.A/C... Z2 A................. to............. .. EOT............................ 2ii C................. (TIT............................. 2.0 A................. (tit ....................... 12.......... .. TIT............................. ZO A................. Z 1 l>............... ii.......... .. TFF............................. m E................. 14............. .. ItlTO......................... 1ft.......... .. l>-2? ........................... 1176.................... .. .. IM4 ........................... IMS...................... is.......... .. UF,....................... aMn.................... S21t.................... a.......... 74.......... .. .... .... .. PTNTT.ORSCAA.I..1...,.................................................. NUCU)................ NuOt`11,.................... DAMro......... *....... 22*G?5.................... 2R*........ .. ... CD'AttOIH..'.O.................................... (Cll,l,N*OU-(iut)... 3*........ 1.7 A.................. 1.7 A................. 1.7 1.7 AA.......................... 1.7 7000. A/C... 1.7 17 7Jnl./...;..A../.C....... 1.7 7U/*I. A/C... 1.7 1.7 1.7 1.7 AIl>I...................................... 1)................. 1.7 A............. 1.7 nr*.a/C... 30*........... . 31.............. 12.......... ta.......... .......... h............... 34.............. .......... E............. Aft ftO 40 Alt m AO CO A0 Aft 40 n At) 45 so AM A0 Aft A0 A0 A0 A0 A0 A0 45 A0 A0 A0 A0 A0 A0 A0 40 A0 45 10 41 0 41.2 32ft 32.* fe 4 31.6 AO 2 30 0 TO h Z5.2 42.0 67. X 14. A IS 6 ai s XL 4 11.8 37.6 30.3 38.4 11.3 38.3 37.8 3ft. 1 fee 27.4 as.7 22. 2 XII fe 4 33 2 10.1 1ft A 30.0 iao jn.mo 42. mt *25.000 1*411, UU0 uu.ono 105,000 32.00U ou.ono 44,000 3ft,0U0 32,000 36 000 43.000 Aft000 40.000 37.000 42.000 4on4.,0o0n0o 7it. 000 55.000 44. U00 17,000 47.UOO 39. OUt Aft. 200 K.Afa 74,000 S3. US) AA.UK> SOHfftt..UU<Ol A0.1)00 4K000 44.000 6.340 Z 040 ZMO 10,000 .SW> sauo Lass 1810 7. on a, am tui low ML100 H)A0 11 too 6 7*0 7,540 RI00 7.060 7,300 ft 3U0 ft 130 ft 085 116ft 6.590 1045 *,1*0 1740 4. SOU I860 A, 400 1Z078670 t) Z700 z*m 2.370 1600 1400 Z*J0 Z4 Z7S0 lino LOW LUO 1.400 Z43S 1670 1.070 LOW two 1640 Z 300 1450 zam ZOSO L 700 Z 460 1,600 Z82S Z 800 ZA00 1,450 ZIM 6 161 XM0 1,740 zsss 1A0 60 t V 170 16 IN 04 ZIO A 10 130 IJO A0 a7s 10 30 Zi f 210 40 110 380 US 31 44 7 1 Smiik-i ci traction for 24 hour* in rx-.rmu^ inlum* irriTnt bu**d od weight of poiymcr. * Tlir*t iumj*i**` wm molded lo: `S', i:: ut4-v 11.7 percent of to aqueous aoluiiun lc | .Cfut uiriuneUiyl araiuoofuia hydru&ide. No food. properties of molded composition are listed in Table I, EXAMPLES 35-52 below. By procedures analogous to that described above, a series of ester-containing polymers filled with Silica A <'' A series of csier-coniaining polymers were filled with various fillers by procedures analogous to that described above for Examples 1-34. Table 11, below, displays the were prepared using various catalysts. The polymers and various ester-containing pohmers, fillers, and catalysts catalysis employed were as follows: that were employed, as well as representative properties. Catalysts: T1PT--Tetraisopropyl titanate. OGT--Octylene glycol titanate (duPont-TYZOR OG organic titanate) (i.e., tetra|2-ethyl-l,3-hexanedio1)titanate). Tbe fillers that were employed are as follows: Asbestos--short fiber chrysolite asbestos. Leached Asbestos--prepared in accordance with tbe following procedure: To a 5-liter three-necked, stirred flask was charged 200 gm. of chrvsotile asbestos and 4.430 ml. of 1.0 N HCI. After healing (101* C.) for three EGf'--Triethylene diphosphite. '5 hours the mixture was allowed to cool and then filtered. 8,485,790 9 10 The leached asbestos was washed three limes with water 2. The process of claim I wherein said process is nd dried in a vacuum oven at 60-65* C. Weight reeov- carried out at a temperature in the range of from about eicd-R6.2 pm. This process removes substantially all the 90* C. to about 250* C for a period of from about S magnesium from the asbestos leaving a very porous silica minutes to about 3 hours. residue. c 3. The process of claim 1 wherein the thermoplastic, Clay A--An attapulgus clay having an average particle ester-containing polymer is a copolymer of ethylene with size of 0.14 micron and a specific surface of about 210 a member of the group consisting of vinyl acetate, alkyl square meters per pram. acrylate, alkyl methacrylate, alkyl maleale, and alkyl Clay 6--An altapulgus clay having an average particle fumarale. size of 0.12 micron and a specific surface area of about jq 4. The process of claim 1 wherein (he thermoplastic, 210 square meters per gram. ester-containing polymer is poly (vinyl acetate). Alumina A--A powdered alumina consisting of min 5. The process of claim 1 wherein the phosphite is ute fibrils of boehmile alumina. The average chemical triethylene diphosphite. composition is as follows: AlOOH--83.1 percent; 6. The process of claim 1 wherein the phosphite is CH,COOH--9.8 percent; SO,--1.7 percent; Water--5.0 )s triphenyl phosphite. percent Alumina A has a specific surface area of 274 7. The process of claim 12 wherein the catalyst is square meters per gram. Alumina B--A hydrated alumina having a specific .tetraisopropy! titanate. 8 Process which comprises beating at a temperature surface area of 18-24 square meters per gram and ao in excess of about 90* C. a mixture of: average panicle size of about 0J 5-0.4 micron. 0 (a) an ethylene-vinyl aoetale copolymer. table It Suiuple Catalyst Cat. Cone. Ester (percent Containing Enter by Wt.) Polymer (pervenl by Wt.) Percent Polymer Bltflnras Modulus, pa.l. Ins'tluble Id 1 Meflusing Toluene R.T. 130* C. Tonefle Elrengtb, pai. as....... ar....... ......TJPT a;....... aa**.............. 441...................... iivru___ 4412............___ TIFT____ 44...... ..... ROP____ 44<5i.............. 47.. .. Tll'T, ..... TIPT....... SI........................ u................. T1I*T.. B........ 1-6 11....... L7 Au.............. 1.6 A....... 1.7 AA.............. L7 A....... 17 A....... A....... ..... ctor it ((0).................. 10 Aft ....... 1.7 B ... A....... 1.7 A....... ..tie.. 1.7 .do.. 116 Al V.ft 110 116 110 IS. 2 412 111 34 7 20. S lu. 1 9.0 11.0 17. S 26,000 45.000 04.000 2S.ono l.oon 04.000 6.o 0070..000000 *1.,230......................................... 1.M0..................... eiono 46.000 2S,.*0O000................................................ *5.000 7,1130.......................... ji.ono NoLnwt OOP C.).. 04.0110 dr c.)______ 7,000 NnLnd (100* CO. 9. JU0 ic nun* c.)............. . 22, SUi sanoo* C.)............... IV, 100 *2 (too* C.)............... iao 3I,1XIS9O0 1.140 1.00 ii..eiuo LX* 1.S90 1.00 1,700 i.tso i.o I. M0 1,200 1.W0 l.* LNO Percent Elonge- Uoo 470 7( IK 110 >00 1(0 10 10 (7 to u 30 sue Ml 0 ao TWhat is claimed is: s' 1. A process for producing Improved filled polymers (b) colloidal silica in an amount of from about 1 to about 80 percent by weight based on the total weight which comprises beating at a temperature in excess of of copolymer and silica said colloidal silica having about 90* C. a mixture of: a surface layer of hydroxyl groups and having a (a) a thermoplastic, esler-contatning~p61ymer' where in said polymer has a polymeric chain of carbon-to- *6 specific surface area of at least about 100 square meters per gram, and a particle size of from about carbon bonds and wherein the ester groups nre con 0.001 to about 0.1 micron, and tained in side groups that are bonded to said pol (c) from about 0.1 to about 8 percent by weight based ymeric chain, on the total weight of the copolymer and silica of (b) a filler in an amount of from about 1 to about 80 percent by weight based on the total weight of 60 polymer and filler, said filler containing chemically a phosphite of the formula OR bound water and selected from the group consisting of silica having a specific area of at leasl about 100 F-OB N>R square meters per gram, and a particle size of from about 0.001 to about 0.1 micron, clay having a 65 wherein each R individually is a member of the specific surface area of at least about 150 square group consisting of hydrogen, alkyl, aryl, alkaryl, meters per gram, and an average particle size of less aralkyl, cycloalkyl, and alkylene phosphite, provided than 1 micron, hydrated aluminum oxide having a that at least one R is an organic group; for a period particle size such that the largest dimension is less of time sufficient to effect a reaction between aid than about 1 micron, and asbestos, and 60 ethylenevinyl acetate copol>mer and aid colloidal (c) from about 0.1 to about 8 percent by weight hated silica, aid period of time being at least about 5 on the total weight of polymer and filler of a catalyst minutes. which is a phosphite of the formula: 9. Process which comprises beating at a temperature in excess of about 90* C. a mixture of: OR 05 (a) an ethylene-vinyl acetate copolymer, p-ob (b) colloidal silica in an amount of from about 1 to about 80 percent by weigh: based on the total weight wherein each R individually is a member of the group consisting of hydrogen, alkyl, aryl, alkaryl. aralkyl, cycloall.yl. and alkylene phosphite, provided that a> least on: R is an organic group: for a period of time sufficient to effect a reaction between s:iid thermoplastic, ester-containing polymer and said filler, said period of lime being at least about 5 minutes. of copolymer and silica said colloidal silica having a surface layer of hydroxyl groups and having a specific surface area of at least about 100 square meters per gram, and a panicle size of from about 0.001 to about 0.1 micron, and (c) from about 0.1 to about 8 percent by weight bated on the total weight of the copolymer and silica of a tetraalkyl tiianate; 3,485,71)0 11 12 for a period of time tu/r>cicnt to effect a reaction between (a) a thermoplastic, ester-containing polymer wherein oid ethylene-vinyl acetate corolymer and said colloidal said polymer has a polymeric chain of csrbon-to- ailica. said period of time being at least 5 minutes. carbon bonds and wherein the ester groups are con 10. Process which comprises healing at a temperature tained in aide groups that are bonded lo said poly in rer" of about 90* C. a mislure of: meric chain, (a) an ethylene-ethyl acrylate copolymer. (b) a filler in an amount of from about 1 to about 80 (b) colloidal silica in an amount of from about I lo percent by weight based on the total weight of poly* about SO percent by weight baseJ on the total weight mer and filler, said filler containing chemically of coflymer and silica said colloidal silica having a bound water and selected from the group consisting surface layer of hydroxyl groups and having a speei- ju of silica having a specific surface area of at least fic surface area of at least about 100 square meters about 100 square meters per gram, and a particle gvr gram, and a particle size of from about 0.001 size of from about 0.001 to about 0.1 micron, clay to about 0.1 micron, and having a specific surface area of at least 150 square (c) from about 0.) to about 8 percent by weight based meters per gram, and an average panicle size of less on the total weight of the copolymer and silica of a 15 than I micron, hydrated aluminum oxide having a phosphite of the formula panicle size such that the largest dimension is lets OR r--OR NOR than about 1 micron, and asbestos, and (c) from about 0.1 to about 8 percent by weight based on the total weight of polymer and filler of a 20 catalyst which is tctraalkyl litanate; wherein each R individually is a member of the group consisting of hydrogen, alkyl, aryl, alkaryl, aralkyl, cycloalkyl, and alkyiene phosphite, provided for a period of time sufficient to effect a reaction between said thermoplastic, ester-containing polymer and said filler, said period of time being at least about 5 minutes. that at least one R is an organic group: for a period of time sufficient to effect a reaction between mid 25 References Cited rth> lene-cthyl acrylate copolymer and said colloidal UNITED STATES PATENTS sili.-a. mid period of time being at least 5 minutes. 11. Process which comprises heating at a temperature in excess of about Vtf C. a mixture of: la) an ethylene-ethyl acrylate copolymer. 30 (b) colloidal silica in an amount of from about I to about 80 percent by weight based on the total weight 3.219.604 3.304,197 3.350.475 3.377.311 3.06 1.577 11/1965 Fischer............................. 260--22 2/1967 Pundxack el al. lit 'IV67 Watanahe elal._____ 260--865 4 /1 Vfx Koch el al.26(1--37 10/1962 Ptueu....................... 260--41 of copolymer and silica said colloidal silica having OTHER REFERENCES a surface layer of hydroxyl groups and having a specific surface area of at least about 100 square 33 Schrader el al.: Radioisotope Study Modern Plastics, September 1967, of Coupling Agents in Reinforced mc:ers per grim, and a particle size of from about Plastics, p. 195. 0.00} to about 0.1 micron, and (c) from about 0.1 to about 8 percent by weight based on the total weight of the copolymer and silica of a Could: Inorganic Reactions and Structure, Holt Rinehan Winston--New York 1961, p. 127. * ittraatlyl liianafe: for a period of lime sufficient 10 40 ALLAN LIERERMAN, Primary Examiner effect a reaction between said ethylene-ethyl acrylate copolymer and said colloidal silica, said period of S. L. FOX, Assistant Examiner time being at least 5 minutes. 12. A process for producing improved filled polymers, US. Cl. X.R. vhi.h comprises healing at,a temperature in excess of 45 260--86.3. 86.7 about V0* C. a mixture of A ^ o J 8Un V>r * United States Patent Office 3,558,485 Patented Jan. 26, 1971 12 3,558.485 FIRE FIGHTING COMPOSITION COMPRISING AN ASBESTOS CONTAINING SLURRY John E. Skvarla, Lewiston, N.Y., assignor to Union Car* bide Corporation, New York, N.Y., a corporation of New York No Drawing. Continuation-in-part of application Ser. No. 556,586, June 10, 1966. This application July 2, 1969, Ser. No. 838,679 Ink CL A62c 3/02 VS. a. 252--7 3 Claims ABSTRACT OF THE DISCLOSURE A method of reducing the flammability of forests, shrubbery, grass and the like by coating such materials with an asbestos containing slurry. precipitates in the presence of certain chemicals is a com mon problem. It is, therefore, an object of the present invention to provide a stable, non-deteriorating and essentially chem3 ically inert viscous water type of fire-fighting composition which satisfies the desirable criteria set forth hereinabove. It is another object of the present invention to provide a viscous water type of fire-fighting composition which is compatible with, and to which can be added, flame10 inhibiting chemicals and foaming agents. A fire-fighting composition for use in accordance with the present invention is a water suspension or slurry of finely divided asbestos, the asbestos content being suffi cient to make the water suspension viscous. The asbestos 15 used, which is suitably present in amounts varying from about 1 to 10% by weight of the water suspension, is ebrysotile asbestos having the following properties: Specific surface area: 60-80 m.Vgm. 0 Magnetite content: 0.04-0.5% This application is a continuation-in-part of applica Reflectance: 72-78% tion Ser. No. 556.586 filed June 10, 1966, and now aban Wet bulk: 750-980 ml. doned. This invention relates to a fire-fighting composition for use in reducing the flammability of forests, shrubbery, grass and the like. More particularly the present invention relates to the use of a "viscous water" type of fire-fighting composition which can be applied by conventional spraying and foaming techniques and which can also be applied by aerial bombardment methods. As described in Chemicals for Forest Fire Fighting published by the National Fire Protection Asosciation in 1963, the characteristics desired in a forest fire-fighting composition include: This asbestos, derivable in large quantities by processing ore from the Coalinga California deposit, is commercially 25 available from Union Carbide Corporation under the designation "High Purity Grade Asbestos" and is de scribed in more detail in U.S. patent application 396,935 entitled "Process for Refining Asbestos and Resultant Product," the disclosure of which is incorporated herein by 30 reference. This patent application describes an effective process for producing asbestos having the aforementioned prop erties which comprises: (1) contacting asbestos ore con taining asbestos, coarse rock, fine gangue and other non- (a) low cost 35 asbestos impurities with water, (2) separating coarse (b) ready availability in adequate quantities in areas rock and fine gangue from the remainder of the wet ore, of primary use (3) comminuting the remaining (i.e. coarse rock and (c) non-toxicity to plant and animal life gangue free) wet ore until all of the ore particles are (d) good adherency to forest fuels able to pass through a screen having circular holes no (e) non-dessicating to vegetation 4(1 larger than about 0.03 inch in diameter, (4) adding suffi (f) quantity requirement per gallon of water is small cient additional water to the comminuted ore to form a (g) mixes easily and readily into a stable suspension or slurry having a solids content no greater than about 3%, solution (5) hydrocycloning the slurry formed in step (4), i.e., (h) not oversensitive to either pH or mineral content of providing a hydrocycloning zone having an inlet, an water 45 overflow, and an underflow conduit, and passing the slurry (i) not subject to deterioration from bacteria, enzymes, through said zone at a flow rate sufficiently high to pro or by action with metals duce a centrifugal force inside said zone at least equal to (j) final characteristics are reached shortly after mixing 50 G's, and at the same time maintaining the ratio of and do not change with further standing or agitation the overflow rate to the underflow rate greater than about (k) flows through fire hoses without serious friction loss, 53 0.5; whereby substantially pure asbestos fibers emerge yet sets up and holds once it is applied to forest fuels. in the overflow, and (6) recovering the purified asbestos fibers from said overflow. A particular class of fire-fighting composition which has In preparing the fire-fighting composition in accordance been developed with hopes of conforming to the fore with this invention, dry fibers of asbestos, or pelletized going criteria is known as the "viscous water" group. A 55 fibers are slurried with water by means of the conven viscous water fire-fighting composition is defined as water tional beater tank or by use of the pump re-circulation which has been thickened by one or more viscosity agents loop of a storage tank. Additionally, in line mixing op and such compositions are advantageous in that in general erations, asbestos can be injected by way of a standard these materials stick and cling more readily to forest solids feeder into a hose carrying water under turbulent fuels than plain water, they spread out in a continuous 00 flow conditions and a suitable slurry will be discharged coating over fuel surfaces, and set up on a layer about from the hose nozzle and applied to forest fuels and three times the thickness of plan water, and on account the like. Also, as previously mentioned, the slurry can be of their greater layer thickness absorb more heat than applied to forest fuels and the like by means of aerial plain water and thereby reduce the flammability of the bombardment techniques and by foaming techniques. fuel. However, previously available viscous water com G5 By way of particular example, a 500 gallon batch of positions, in spite of their advantages, have not satisfied the fire-fighting composition of this invention containing all of the abovememioned requirements and have been 3% by w-eight asbestos is prepared in a conventional found to have, in several respects, serious disadvantages. storage tank having a re-circulation loop by: For example, previously available "viscous water" pre (1) Introducing about 450 gallons of water into the pared through the use of organic materials are subject 70 tank, to bacterial action and, on account of this, loss of vis (2) Re-circulating the water through the tank under cosity can occur rapidly. Also, the formation of insoluble turbulent flow. ! -- C..> CJ) Co aj i 3,558,485 3 (3) Adding about 125 pounds of asbestos to the tank while the water is re-circulating. (4) Continuing re-ciruulaiion under turbulent flow con ditions to provide a complete circulation of the water- 4 The data of Table III ilia 'rates this aspect of the pres ent invention and shov.s the relative amounts of free and retained water for asbestos slurries of this invention when placed on a 100 mesh screen and allowed to drain for asbestos mixture. With the usual equipment this can be c 5 minutes. accomplished in a matter of minutes, (5) Topping off the tank by adding 50 gallons of water, and (6) Continuing re-circulation to provide one more com TABLE 111 Water retained in tinny Fnw water plete re-circulating of the water-asbestos mixture under turbulent flow conditions. By following the foregoing pro.-edurc. a stable water slurry of asbestos characterized by a gelatinous structure is quickly obtained which has a high viscosity and which Tcrt^sit by weight Li Murry: ) ........................................................ ...... 5 ......................... ............................ ......... ....... 4 ... ... *...................................................... . .. . 47 68 74 7U W 63 Si J6 21 IS remains stable indefinitely and can be readily applied to the surfaces of forest fuels by conventional spraying, foam ing and atrial bombardment techniques. Slurries of water and asbestos in accordance with the present invention can be adjusted with respect to viscosity by varying the asbestos content. All water-asbestos slur *' The composition of the present invention is addition ally advantageously characterized by pseudo plastic flow characteristics which yield flow rates shown by the test results of Table IV for a 3Cc asbestos-water composition 0 of this invention through a 1-inch (inside diameter) hose. ries of this invention are chrracterized by a gelatinous TABLE IV structure created by the colloid-like asbestos fibers (which are about 200-300 angstroms diameter and 0.25-10 microns in length) and Table 1 show's the viscosities ob Flow rates, 35 asbestos slurry through 100 feet of 1 in. IJD. rubber hose tained with different amounts of asbestos. <v, Flow, gal./min.: Pressure, p.s.i.g. 10______ ------------------ 24 TABLE I.--VISCOSITY OF WATER-A'HF.STOS FLURRIES OF THIS INVENTION. MEASURED BY UJtOOKFiELt) MODEL LVF II ELI PATH VISCOMETER 20.......... 30------------ ..................... 30 ____________ 34 Brook* field tpindl-timi 35.............. no 40---------- ____________ 36 ..................... 47 WUlpols-'N To further illustrate the properties of the waterasbestos compositions of this invention Table V shows Asbestos jTvril by uvfcbl: 1......................... T-A o...............................................................T-C 4.................................................... T-H n................................. T-V a comparison of flow rates through a one-inch I.D. hose r. ii fcl.MW 1M.MUU _ of various asbestos-water slurries with respect to plain 0 water. * t* 132, non TABLE V 4 A particular advantage of the present invention is that its high viscosity provides exceptionally good adhesion to forest fire fuels. To illustrate this feature, identical wooden blades of known surface area representing forest fuel material were dipped into plain water and various asbestos-water sample slurries of this invention and there by coated and the weights of retained material were meas ured and compared by calculating a slurry/water ratio as follows: Percent of plain water flow Flow Telocity velocity, tot aaxna tl.vec. pressure Asbestos-water composition: 2.J" asbestos................................... Do.............................................. 3.4~ asbestos................................... Do............................................. 4.2% asbestos................................... .............. Do............................................. .............. 15 20 26 76 M an *0 Wfirbt In: rear. of bbde dipped in sample S/W---------------------------------------------------------- Weight increase of blade dipped in water In addition to the foregoing advantages it has been also found that on account of the aforementioned email The results shown in Table II indicate the weight of an adhering film on the wooden blades and thus the thickness of the film for various compositions of this in vention as compared to water. The thickness of the film indicates the effectiveness of the slurry in reducing the flammability of the fuel material. **0 **3 fiber size and high purity of the asbestos addition, that the asbestos-water composition in accordance with this invention can be used with all standard fire-fighting equip ment without dancer of erosion or plugging. By way of example, Table VI shows the relative abrasiveness of the asbestos addition of this invention as com pared to other materials. TABLE II TABLE VI Sample (percent asbestos by weight): 0 (plain water) 1 S/W Relative abrasion factors 1 ............................................................. 2.0 Asbestos addition material 1 2................................................................................. 3.6 Bleached sulfite pulp 2 3............................... -............................................... 6.4 Dialomite-_________________________________________ 10 4............................................... 8.4 Bentonite clay39 5................................................................................. 9.1 6 ................................................................................. 10.7 The foregoing Table VI shows for example that the asbestos is only one-half as abrasive as sulfite pulp and A further advantage of the asbestos-containing com one-tenth as abrasive as diatomite. The method and position used in the practice of this invention is that it is equipment for making the measurements of Table VI capable of retaining large amounts of water within its were described and published in the Proceedings of the characteristic gelatinous structure and this provides in To Conference on "Nuclear Applications to the Wood, creased opportunity for waicr penetration which is im portant in fighting ihe so-called "duff" fires and under other circumstances. Thi\ feature is of particular im portance since most if not all previously known "ti-.-o't-. Paper and Pulp Industries." The conference was held Apr. 23-24. 19M, and was sponsored by the Institute of Technology of Washington Slate University and the Divi sion of Isotopes Development of the U.S. Atomic Energy water" type compositions do not hate this capability. 73 Commission. t .7 CT O / - . 3,558,485 6 Id a further embodiment of the present invention, ooe to produce stable foams of high strength with low drain or moTe fire-retardant and/or fine-suppressing chemical additives, such as ammonium sulfate, ammonium phos rates. Only relatively small amounts of foaming agent are required, and conventional foaming techniques can phate and ammonium chloride can be added to the be used. asbestos-water composition to provide long-term fire pro . The following Table VIII shows test results of foams tection. Also, wetting agents such as commercial deter prepared in accordance with the present invention. In gents, e.g., Tergitol,1 can be used with the asbestos-water obtaining the data of Table Vm, a 100 ml. solution of composition, with or without chemical additives to pro water or asbestos-water slurry was made with the in vide increased penetration of the fuel upon release of dicated foaming agent. The solution was agitated for 30 "free water" from the slurry. j0 seconds and the volume of foam produced was compared The aforementioned fire-fighting compositions can be to the original 100 ml. volume and the ratio recorded easily prepared, for example by dry blending the asbestos as the Foam Ratio. The foam was observed and the times with the chemical additive and if desired other materials noted at which 25% (25 ml.) and 50% (50 ml.) of solu cuch as vegetation coloring dyes and corrosion inhibitors. tion had come out of the foam. It can be seen from The dry mix can then be converted to an aqueous slurry 13 Table VIII that the compositions of the present inven by the techniques previously described. tion produce stable long lasting foams. The following Tables Vll(a) and Vll(b) show suit A further test was performed by placing a portion of able compositions in accordance with the present inven the foams produced on surfaces of kerosene and acetone tion containing chemical additives. to determine the effectiveness of the foams with the re- TABLE Villa).--AQUEOUS SLURRIES 20 spective type of fuels represented by these materials. A "Y" in Table VIII indicates that the foam did not break Additive Percent by weight additive down and shows the foam to be effective against fires supported by the material specified. Of particular sig nificance is the finding that with the use of foaming Asbestos, weight percent: 1-10.................................... 1-10.................................... 1-10.................................... 23 agents (1) and (2) with an asbestos-water slurry of this 5-Si invention, a foam is obtained which is "compatible," i.e., 5-35 5-35 stable, in the presence of both the "kerosene," i.e., hydro carbon and "acetone," i.e., polar type fuels. table vui --commercial foaming agents and asbestos MIXTURE Foaming agent* (3) National 09.................. (4) National S% cold........ Percent by wi. foam agent Percent by wt. asbestos Drain Time, min. 25^ SOTr Foam ratio Compatibility with-- Kerosene Acetone 20 11 s 6Y 5 6 ............ Y 20 5 4Y 11 0 2Y 1 2 15 25 2Y Y 3 02 4Y 1 1 27 2Y Y s 06 1 15 1 2 15 5 2Y 2Y (5) National regular__ (6) National regular... 3 02 1 1 10 1 2 20 5Y tY 2Y a 024 5Y 1 1 11 25 8Y 1 2 10 2Y 2 024 5Y 1 1 14 25 2Y 1 2 25 2Y Commercially available under these names: (I) Trademark of Vnlon CaiWde Corp. (anionic type). (?) Protein based. (3) Product of National Foam Systems Inc. (4) Product of National Foam Systems Inc. (5) Product of Naiional Foam Systems Inc, (6) Product of National Foam Systems Inc. . . a Cj 64 1 TABLE VII(b).--DRY MIX In addition to the above-mentioned advantages, the Additive: Ammonium sulfate 1-70 Ammonium phosphate 1-70 Ammonium chloride1-70 Weight of additive/ asbestos-water composition of this invention has been weight of asbestos Co found to be unaffected by the pH or mineral content of the water. Also, the composition is non-toxic to plant and animal life; its final characteristics are attained shortly after the mixing of asbestos and water, and the asbestos- water composition can be stored indefinitely. A still further embodiment of the present invention in The parameters specific surface area, magnetite con volves the use of foaming agents with the asbeslo-water 70 tent, reflectance and wet bulk, previously mentioned here- composition, with or without chemical additives. Non icabove, are defined as follows: ionic, anionic, cationic, and protein type commercially Specific surface area is calculated from adsorption data available foaming agents have been employed and found using the BET (Brunauer, Emmet, Teller) method as de 1 Trademark of Union Carbide Con>oratlon. scribed in Brunauer, "ITie Adsorption of Gases and 75 Vapors," Princeton University Press (1945). - .4 i 3,558,485 78 Magnetite content is measured by a permeametric de 10 percent by weight of the suspension and is character vice patterned after ASTM standard method D-l 118-37 ized by the following: and modified with respect to sensitivity to measure a limit of detection of 0.005% magnetite, and the range extended to measure 0.10% magnetite in the mid-scale of the in strument. Reflectance is measured on a sample prepared accord ing to TAPPI (Technical Association of the Pulp and Specific surface area: 60-80 m.Vg. Magnetite content: 0.04-0J% Reflectanceff 72-78% Wet bulk: 750-9&^ ml. 2/A method in iccordance with claim 1 wherein said Paper Industry) standard T-452-m-58 and reported as percent of ultimate reflectance based on magnesium oxide slurry additionally contains a dissolved water-soluble fire suppressing substance selected from the group consisting as 100% reflectance. ]!J of ammonium sulfate, ammonium phosphate and am Wet bulk is a measurement of the terminal settled monium chloride. volume which a given weight of an asbestos suspension will have at the end of a specified period of time. It is 3. A method in accordance with claim 1 wherein said sluiry additionally contains a foaming agent dispersed also a practical indication of the completeness of the therein. fiberization or openness of the asbestos. The specific test References Cited is as follows: 2 grams of asbestos are placed in a gradu UNITED STATES PATENTS ated cylinder containing 1000 ml. of distilled or de mineralized water. The cylinder is then gently inverted and returned to an upright position 10 times and then placed on a reasonably vibration free bench. The level 20 of the asbsetos suspension (clear water interface) is read at the end of one hour. The volume of suspension is the "wet bulk." ---------- What is claimed is: N 25 2,551,919 2,652,325 2,661,287 2,880,172 2,901,428 3,196,108 3,445,384 5/1951 Williamson et al---------------169--14 9/1953 Novak 252--3I3X 12/1953 Barbaras...................... 252--313X 3/1959 McCutchan 252--2 8/1959 Schulenburg 252--2X 7/1965 Nelson252--2X 5/1969 Schreiber 252--2 1. In 4 method of treating forest* fuels material to JOHN T. GOOLKASIAN, Primary Examiner \ reduce &e flammability thereof by coating said material with a film of water, the improvement which comprises coating said material with a slurry consisting essential D. J. FRTTSCH, Assistant Examiner ly of a suspension of finely divided asbestos in water U.S. Cl. X.R. wherein the asbestos constitutes between about 1 and 30 252--2, 3, 4, 8.1 I 2>- C.5 C3 f'J United States Patent i")3,619,354 [72] [21] (22) f 45] j 73] Inventor AppINo. Filed Patented Assignee Robert G. Wooirry Lrwbton, N.Y. 796,913 Feb. S. 1969 Continuation-in-part of Ser. No. 576,248. Aug. 31,1966, abandoned Nov. 9,1971 Union Carbide Corporation New York, N.V. [54] LAMINATED FELTED SHEETS AND ASBESTOS CONTAINING COATING COMPOSITION FOR USE THEREIN 3 Claims, No Drawings [52] [51] 150 ] US. Cl............................................................ 162/129, 117/28, 117/140. 161/156, 161/205,162/153. 162/155 lot.CL........................................................... B32b5/08, B32b 19/06, D2lh 5/18 Field of Search............................................... 162/3,127, 129.132, 133,153,201, 186; 161/153,156,205; 117/140.28.126,106/63 15b] 367,424 1.558.495 2.626.213 2.881.072 2.927,038 References Cited UNITED STATES PATENTS 8/1887 Merrill........................... 10/1925 Overbury....................... 1/1953 Novak............................ 4/1959 Clark.............................. 3/1960 Sehule............................ 162/129 162/129 161/205 X 162/201 X 117/140 X 2.993.802 7/1961 Casconc.......................... 3.246.767 4/1966 Palletal........................ 162/129 X I17/I40X OTHER REFERENCES Paper Trade Journal (Feb. 14,1966) pg 4(t- 4." New Type of Asbestos Shows Advantages in Papermuking" Ingalls rl ul " Pulp and Paper,'* Casey. James P., Intcncience Publishers,N.Y.(1961 l.p. IS33-4Vol.3 Primary Examiner--S Leon Bashore Assistant Examiner--Alfred D'Andrea, Jr. Attorneys--Paul A. Rote. Thomas I. O'Brien. Frederick J McCarthy. Jr., Robert C. Cummings and Lawrence G Kaitriner ABSTRACT: Disclosed is a process for forming laminated felted sheets wherein a wet base sheet of fibrous material is formed on a paper making screen and. before the wet base sheet is removed from the screen, a nonseparable. uniform asbestos-binder composition is applied thereto. The composi tion comprises an intimitale mixture containing (a) at least 50 percent by weight of chrysotile asbestos having a specific sur face area from about 60-80 m'/g-, a magnetite content of from about 0.04-0.5 percent, a reflectance of from about 72-78 percent, and a pulpabiiity such that 0.2-- I percent of the asbestos is retained on a 65 mesh Tyler screen and (b) a binder therefore. The ratio of asbestos to binder, on a dry weight basis, ranges from about 3:1 to 9; I. 3,619,354 12 LA MJNATED FELTED SHEETS AND ASBESTOS timale mixture of chrysolite asbestos fibeis having certain CONTAINING COATING COMPOSITION FOR USE critical properties (hereafter defined) and a binder therefor. THEREIN Said competition, which may also be used to form a self-sup porting sheet, may if desired, include optional ingredienti The desirability of adding a binder to nonwoven felted 5 such as conventional paper-making fibers, filters, pigment*, sheets has been known for a long time, and numerous binder* dyes and the like. have been used for this purpose, for example, natural and To be suitable for purposes of this invention the asbestos synthetic resins, gums slarches, waxes and various rubbery lat used must have the following critical properties: tices In accordance with prior an methods these binders have been incorporated into the felled fibrous materials in one of 10 IHfflil BUI 1^10 V| 004-0 0)% three ways. The most common way of incorporating the lUfkctMC* ?2*Y| binder is to mix it with the fibrous furnish composition and Oulp*btHtj 0 2-100 then lay and dewater the mixture on a conventional Fourdrini- Asbestos having the aforementioned properties is commer* cr screen or cylinder machine. This type of process suffers from a variety of difficulties, the most important of which is 15 cially available as high purity grade Calidria* *Ttdmirfc of Umm CirMc Corp nbt>w improper coagulation and self-agglomeration of the binder causing weakness and lack of uniformity in the paper. The properties of the asbestos material set forth above are Another way of incorporating binders into felted fibrous critical in the sense that only by use thereof are the desired sheets has been the practice, disclosed, for example, in U.S. results of the invention obtained. Pat No. 2,022.687. of first forming a fibrous web upon a 20 Specific surface area is calculated from adsorption data paper-making machine and thereafter impregnating the web. using the BET (Brunauer, Emmet, Teller) method at while supported on the paper-making screen, by passing it described in Brunauer. "The Adsorption of Gases and through a permeating bath containing the binder material. Vapors," Princeton University Press (1945). This practice suffers from the disadvantage of requiring a separate saturating machine, as well as difficulty in controlling 25 Magnetite content is measured by a permeametric device patterned after ASTM standard method 0-111B--57. Since the amount of binder added to the original sheet. Neither of the lower limit of detection of the ASTM device is only about the above-described methods serves to produce a laminated or 0.20 percent magnetite, the ASTM method has been im coated structure, but rather produces a more or less imper proved with respect to sensitivity to measure a limit of detec fectly impregnated sheet. A laminated sheet can, of course, be made by simply coat 30 tion of 0.005 percent magnetite, and the range of measure ments has been extended to measure 0.10 percent magnetite ing the surface of finished paper with a rubber, resinous or in the midscale of the instrument, in order to obtain this waxy binder. Such products, however, tend to have poor adhe greater range and improved sensitivity, the ASTM method has sion between the coaling and the paper. been modified to delect the phase changes of the current It has long been desirable to produce a paper product which 35 generated when magnetic materials are placed in the trans contains on at least one tide thereof a coating of a binder former core rather than the voltage changes generated. which is integrally bound to and substantially inseparable from Reflectance is measured on a sample prepared according to its paper base sheet, i.e. to produce a laminated product TAPPI (Technical Association of the Pulp and Paper Indus wherein the lamina will not separate, and to be able to apply try) standard T-452-m-5R and is reported as percent of ulti such coating to the base sheet simply, economically and 40 mate reflectance based on magnesium oxide as the standard of without the need for additional complex machinery. 100 percent reflectance. OBJECTS The pulpability of the high purity asbestos must be such that less than 1.0 percent and preferably less than 0.5 percent is It is an object of this invention to produce a coated non retained on a 65-mesh Tyler screen when measured in ac woven felled fibrous sheet containing on at least one surface 45 cordance with the procedure described below. The term "4-65 thereof a substantially nonseparable uniform and smooth rub --mesh" is used tu mean the amount, expressed as the percent bery. resinous or waxy coating. of the sample, which does not pass through but is retained on a It is another object of this invention to provide a process for 65-mesh Tyler screen The measurements are made on a wet applying t:iat least one surface of a felted fibrous base sheet, a pulped sample rather than a dry sample, since the particle size resinous, rubbery or waxy coating by use of conventional 50 under wet pulped conditions is significant for purposes of paper-making machinery. paper manufacture. The pulpability is determined by adding Ii is yet another object of this invention to produce a com 40 g. of asbestos and 2 liters of water to a TAPPI Standard position suitable for coating nonwoven felled fibrous base Disintegrator and agitating the mixture for 4 minutes. A 250 sheets, such as paper and the like, which coating will be in ml. aliquot sample is then taken from the disintegrator and tegrally bonded to said base sheet and form a uniform, smooth 55 diluted to 3 liters with water. The diluted sluny is then poured coaling thereon through a 65-mesh (Tyler standard) wire screen held at an DESCRIPTION OF INVENTION angle of about 30 from the horizontal position. The oversize remaining on the screen is washed back into a 4 liter beaker The above mentioned and other objects which will become 60 diluted with water and poured through the screen again as be apparent from the detailed description to follow arc achieved fore. The oversize remaining is then backwashed, diluted and by a process comprising the steps of! I) providing a base sheet poured over the screen a third time. The oversize remaining is of felted fibrous material on a paper-making screen, and prior then dried at about 105 50 C. and weighed The net weight of to removal of said base sheet from the screen. (2) applying on the oversize multiplied by 20 is the percent -t-65-mesh asbestos top of sai l base sheet a composition comprising an intimate 65 materia] contained in the original sample. This is the value mixture ol chryvitile asbestos fibeis having certain critical referred toss the "Pulpability." properties (hervatie: defined) and a birder therefor. Table 1 below- illustrates the differences in the properties of Another aspect of this invention consists of a laminated the closest chrysolite asbestos of the prior art and the pi <duci consisting essentially of :t felted fibrous base sheet chrysolite asbestos essential for use in the present invention ard integially Kin,led thereto a coating or lamir.a; the latter 70 Although Ccalinga chrysolite' asbestos is prelcrrcdawk^ comprising an intimate mixture of chrysolite asbestos having source of ll.r asbestos, any chrysolite asbesiM^^^^^H certain critical properties thereafter defined! and a binder A I C544 therefor. A third aspect of this invention consists of a composition, suitable for coaling nonwoven felled sheets, comprising an in- 75 *Coaliftgi chryyxik Califomi* * mined fr*n j l.iTr drroMt rw.ii < 3,619,354 34 for use in this invention. provided it has the critical properties tional paper making fillers and/or pigmenu may be uacd, as defined above. well as mixtures thereof. Furthermore, fibrous materials other than asbestos, both synthetic and natural, may also be in cluded. if desired, in the coating composition For example, 5 one or more natural or synthetic mineral or vegetable fibers TA1U.K 1--roMI'AKATIVF. PHYSICAL PROPERTIES OF ASHF.STOS FIRER8 may be added to the composition. In all such cases, however, the weight of asbestos having the critical characteristics previ T ypp of 4**mo* < `oiivn.t imii.k.l.r.o.a..li.n..fa....... for Invention___ Bpedflc Ppirpnt Ptfcenl turfiice fpflec* mi^np- ini, Inner tltp IHt !#-Jl 60-64 I.M.0 72-7* 0-04-0.0 M-S'i 60-60 Pulp- ously described must be at least 50 percent of the weight in the ablllly percent 4-flS 10 composition. The asbestos in such a coating composition is be lieved to act as a coupling agent between the binder and the meeh other fiber or nonfibrous additives, since the cationic nature 10-10 of the asbestos is believed to be attracted by the other fibers, 10-6T the nonfibrous additives, as well as the latex binder, all of fr 1-1. 0 which are anionic in character The binder is preferably added 15 after the asbestos and additive have been adequately mixed, since the asbestos will cause the binder to coagulate. The asbestos-binder composition of this invention is novel Binder, which are useful in the preparation of the coating and unusual in that it can be applied directly on top of a wet composition of this invention include all of the common sizing agents used in the paper industry, such as animal glues, 20 base sheet before the sheet is taken off the paper-making screen. Such "on the wire coating" has not previously been starches, gelatin, rosin, rosin derivatives, waxes, bituminous feasible because coating formulations tried in the past have materials such as asphalts, tars, pitches and bituminous as well drained through the base sheet. Lise of asbestos hiving the as resinous and rubbery lattices. critical properties previously defined "holds out" the costing Synthetic, resinous and rubbery lattices are the preferred binders. Illustrative suitable rubbery lattices are copolymers of 25 composition from the base sheet, and enables the bindet com position to be applied directly onto the paper making screen butadiene and styrene (i.e. GR-S rubber containing 50-80 containing the wet base sheet. Furthermore, there is no need percent by weight butadiene), copolymers of butadiene and for using organic surfactants, welting agents, dispersing acrylonitrile (i.e. Buna--N--or Hycar rubber containing agents, or other flocculating agents required by prior art 50-80 percent butadiene), polychloroprenes (i.e. neoprenes), 30 methods to obtain flocculation and deposition of a binder onto homopolymers of butadiene, butadiene-isoprene copolymers, the fibers. The critical properties of the above described and terpolymers of butadiene, styrene and acrylic acid or asbestos itself assure both proper coflocculation of the binder lower alkyl acrylites. onto the asbestos and deposition of the asbestos-binder coal Illustrative resinous binders which are useful are ther ing onto the base sheet. mosetting resins such as phenol aldehyde resins, and 35 Any felted product which car. be prepared on a paper mak melamine formaldehyde resins. Suitable thermoplastic resin ing screen can be used as the base sheet in the present inven binders include, for example, vinyl and substituted vinyl resins tion. These felted products can be formed from organic, inor such as polyvinylchloride, polyvinylacetate, polyvinylacetal, ganic or mixed materials. Paper base sheets are preferred. As polyvinylalcohol. polystyrene, polyacrylates, polymelhacry- used throughout the specification and claims of this disclosure lates. polyacrylonitrile, polyacrylamide and copolymers of 40 the term "paper" is used in its generic sense, i.e. to include these materials Any resinous binder is useful for depositing any nonwoven. felted fibrous sheet, including but not the asbestos of this invention onto a base sheet, as long as it is restricted to bond, wrapping, tissue, printing, wall and backing dispersible in an aqueous medium or suspendible therein in paper as well as cardboard, wallhuard. millboard, and the like. paniculate form. Suitable inorganic fibrous inj-.eiials for base sheets include The coating composition is prepared by first dispersing the 45 glass wool, mineral wool, and silicate fibers Useful organic asbestos in an aqueous sluny by means of a high shear device; fibers include, for example, cotton, silk. hemp, ramie, alpaca, for example, a Reitz disintegrator, a Fitzmill or a waring hair, fur and animal bristles Useful synthetic organic fibers blender. The binder, usually in an aqueous suspension, is then blended in with the asbestos using low shear mixing such as obtained with an ordinary mixer. The concentrations of both the asbestos slurry and the bindet suspension are ordinarily kept below about 3 percent solids b. weight, since at higher concentrations the composi tion becomes too viscous for easy handling. The proportions of asbestos to binder are controlled to give optimum efficiency so 55 are fibers made from po'yamides acrylates, polyesters, cellu lose acetate, regenerated tcllt-luve (rayon), polyvinyl chloride, polyethylene, polyurethane. polytelTafiuoroethylene and the like. Preferred base sheets are those made from conventional cellulosic pulp used for the manufacture of paper for example, mechanical, semichemital. sulfite, sulfate, or craft (soda) pulp. Mixtures of cellulosic pulp or nurtures of cellulosic and nonccllulosic fibers may also he used. in terms of the retention of the solids on the paper-making screen. The asbestos content, however, must be sufficiently The paper base sheet useful in this invention may have in cluded in it conveniio.ial fillers such as. for example, clay, high to insure that its cationic charge will be adequate to sodium silicoaJuminate. diutonnreous silica, calcium silicate, coflocculate all the other solid components of the mixture. If 60 talc, calcium carbonate, calcium collate, barium sulfate, zinc the concentration of the binder is too high, the binder in ex sulfate and titanium dioxide Such fil ers may be incorporated cess of that which the asbestos can flocculate will in large part, not only into the base sheet, but also in:o the asheslus coating be lost by draining through the base sheet into the white water. composition of this invention, if desired. The optimum proportions of asbestos to binder will vary de In general, a base sheet is made by first preparing a dilute pending upon the particular binder and other additives used. 65 aqueous pulp of suspended fibers, incorporating inio the pulp Preferably. the ratio of asbestos to binder (on a dry weight ba desired additives suen a.- fillers or pigments to make a paper sis) is from 3.1 to 9 1. The same- proportions are useful furnish composition, depositing the Turin- b composition from whether the composition is to be used for coating purposes or a head bet onto a moving fine mesh screen, and then draining for making an extruded. self-supporting film. Self-supporting the excess water through the setecn. The ashestos-binder films of l.iis composition have the properties of an asbestos 70 coating comp.-sili ir. ot this inseRtioi is then applied direc'ly filled plastic fll-.ii, *rd can be used, for example, as packaging onto the wet fctiej fioiouc web or sheet wmle the latier is still film or a<> wallpaper moving or. the papsi t. diking screen The c.. dir,;; str, is con Th; asbestos-binder coating composition may contain addi tives sue i. a> fillers pigmenu or fibrous materials Th-: use of veniently carried .>ut I--, naming a second hc..J R x 1 .n wh; n the coating composition is anpueH onto tht wr. lu;. cv mrJ TiO, and cl.y are illustrated below, however, uij ccnven- 75 screen uij 3,619,354 56 EXAMPLES 1-12 grounu wood and sulfate was 250. The only additive used in Two-ply laminated aheeti consisting of a cellulosic base sheet with a coating of asbestos and binder were prepared on a laboratory Noble and Wood handshect machine using the fol lowing procedure. A base sheet having a basis weight of 60 $ the base sheet furnish was alum, added in sufficient amount to give a pH of 4.5 at the first headbox The first headbox con tained the furnish composition for the base sheet, and the secondary headbox contained the coating composition for the g./m* was first prepared by adding unbleached craft pulp to the deckle box of the handsheet machine and allowing it to cop laminate. Three different furnishes were used in the secondary head- drain almost completely. Then a second composition consist box for laying down the top ply of the two-ply paper. The fust ing of a mixture of binder and asbestos having the critical pro perties heretofore defined was poured on lop of the base sheet top ply coating composition, labeled composition A in table III I below, consisted of 85 percent asbestos and IS percent latex which was still in the deckle box. The proportions (on a dry The second top ply coating composition, labeled composition weight basis) of asbestos to binder used are given in table II B in table III below, consisted of 40 percent asbestos. 40 per below. In examples I through 7 the binder used was an aque cent clay and 20 percent latex. The third top ply coating com- ous dispersion of a synthetic late of a copolymer containing .. position, labeled composition C in table 111 below, consisted of about 60 percent styrene and 40 percent butadiene. In exam 3 52.8 percent asbestos. 27.2 percent TiO, and 20 percent iates. ples 8 through 12 the binder used was an aqueous dispersion All of the coating compositions were applied as I percent of a copolymer containing about 40 percent styrene. 5 percent solids slurries directly onto the wet base sheet as it moved con acrylic acid and SS percent ethylhexyl acrylate. The asbestos tinuously along the Fourdrinier wire The asbestos used had latex coating composition contained about 1 percent solids. It 2q the critical properties set forth above In all cases the Iates was added to the deckle box slowly in order to minimize the used was an aqueous dispersion of a copolymer containing disturbance of the wet cellulosic base sheet. The deckle box about 60 percent styrene and 40 percent butadiene. was then allowed to drain completely. The laminated sheet One objective of this series of experimental runs was to was then removed from the deckle box. pressed with a felt make the top layer as heavy as possible, and to apply it onto a press, and dried in a drum dryer operated at a temperature of 25 light base sheet as well as onto a heavy base sheet. Changes in about 105* C. The heat of the drier not only dried the the thickness of both the top ply and the bottom ply were laminated sheet but also cured the latex. made by setting the flow rate from a headbox at a steady rate Twelve samples were prepared in the manner described and then adjusting the speed of the Fourdrinier wire. Once a above and tested to determine optimum retention of the coat base sheet had been run long enough to insure steady state ing. as well as the physical properties of the laminates 30 conditions, the flow of top ply furnish was started from the produced. second headbox and increased slow ly until the wet web ap The data from table II demonstrates that optimum retention peared to be just on the verge of breaking between the couch of the coating is achieved when the ratio of asbestos to latex roll and the first press Under these conditions the run was (on a dry weight basis) is from 80.20 to 90.10. in other words, continued for 10 to IS minutes. Thereafter the wire speed was when about 10-20 percent of the asbestos latex composition is 35 changed, and the procedure repeated with a different top ply latex and 80-90 percent is asbestos. The data above also or coaling furnish. demonstrates that in general the best physical properties are Samples of paper were taken from each set of runs and cut obtained when there is maximum retention of the coating. into sheets Some of the sheets from each set were calendered EXAMPLES 13-22 at room temperature ar.J some a; approximately 230* F. After 40 conditioning at a constant temperature and humidity room The following examples demonstrate the method of making critical wax tests were made on the calendered sheets, as well a two-ply laminated paper, in accordance with the invention, on a continuous paper-making machine by using b secondary as on uncalendered samples of sheet The results of the critical wax tests are shown in table III below head box on a conventional Fourdrinier machine. The base The cntica) wax tests were conducted in accordance with sheets were 43 TAPPI standard test T-459 su-65 This test consists of taking i aelf. ii Top ot ivt-ntlon to l.itf-x : S^ror.i.t I-erceni t:itu e ` Tins'.;.,strength nn *rt 'n* j HtO dserpUon fmn.utrt) Oil d*porlion (rrJnuiei J................ ** 4.......... t ti .. ... 7 * *............ 1*. .... h.............. .............. s>) 5; sj !*: ** |0 21 Pi.'. 12 3 0.7 i'7 41 11. J 23. ft ft.f M U.7 24.6 in a 43 U.2 2.0 13.0 W tr:j ]* 4 2*. 7 V. M 27.ll ft. ft* Ur : 4 6.4 2.0 6! 13> IU.T 4.7 fcl tM U.U 14.7 10.6 7* f4 >4 1 >3 S 10.3 >4 15 0 jr.7 12 0 *4 6vi r. * if. a 20. ft 1ft ft 51.u 77 f )i*i <i 4.1 ** Aft u l`i il 3ft 44 37. o *1." 4u il 44 11 <T-.v lsii.lr.ati I. In. jj'j.j*.-*! it- u,r *)}*,; ] ivtttTiuMr fititrinirt.u **i!h :i r.iv according tc TAI 1*1 . _,*i If.** :s |fi<-: m jw ly |<kvlrrf a drup vaf-i on thi* of tls * f.- ..nir.c thf !i:uf in mlnutt*. for trie w.tU-r 10 l<r ttfsori* J. 4 fill ij llun vji drirfnn:st*1 In tin- 'atm* i^aim^r vu*. r ;'Jj-fifpi|'*n. u*lni* oil*- ;!.>; made from a furnrsh containing percent wood and 50 per vert hlcjjhed soft wood sulfate pulp The sulfate pulp was rclincj to a frccncss <>f 370 and iht frrrness of the mixture of 75 a standard series of wax sticks, eavh n.iving .i different 0 ki ness, heating them to their melth-e ,v:ir a : .. each of the slicks to the paper sheet The nur.ihn o! the A ; 3 5a6 7 TA1ILK 111 Ksamiil*. Wire *(*4 Top (Ip.m.) ply n........... ___ )4 .......... 13.......... .___ 18........... ___ i:............. i*............. 1*4............. yii .. . .. o21> ........... 40 A B 90 B B B to B a9s0 r c 46 c 76 c Wrieht Buts ratio wettht. top plr: (yro./m.) but ply 117 . 1M .91 100 .as US .91 m .76 IDS 1.00 109 .as 3 .S3 M .as 79 . 3.619,354 Critical wu number Calen dar'd room Unctten* temperstrad tore 7 10 6 6 a9 77 69 10 10 10 10 69 fV llol eaten- rrwt 3XT F. 7 11 10 11 10 10 11 11 10 10 8 highest numbered stick that does not pull fibers from the sur aheet from said screen face is the critical wax value of the paper. It can be teen from 2. providing a nonseparable, uniform, asbestos-binder coat table III that very good bonding between the plies was ob tained as indicated by the critical wax numbers ranging from 6 20 ing on the surface of said base sheet by applying on top of said wet base sheet before said wet base sheet is removed to 11 Some increase in critical wax was obtained by calender from the paper-making screen a composition comprising ing the sheet, with hot calendering giving the best results. The an intimate mixture containing at least 50 percent by tests also indicate that an increase in the ratio of latex to weight of chrysotile asbestos characterized by a specific asbestos and pigment increases ply bonding. The laminated paper of the present invention hat numerous 25 surface area between about 60 to 80 m'/gm.. a magnetite content of from about 0.04 to 0.5 percent, a reflectance advantages not possessed by prior art materials, such as im of about 72 to 78 percent and a palpability such that 0.2 proved ply bonding and low cost of manufacture due to the to I percent of the asbestos is retained on a 65-mesh fact that separate equipment for coating is not required. The Tyler screen and a binder therefor, the ratio of asbestos to coated paper of the present invention is particularly useful for one side "hold out" items such as paper plates, drinking cups, 30 binder, on a dry weight basis, being from about 3:1 to 9:1. 2. The process of claim I wherein the coating composition flexible packaging and the like. applied on top of said base sheet contains an additive selected I claim: from the group consisting of fibrous materials, fillers, pig 1. A process for the manufacture of laminated sheets com ments and mixtures thereof. prising the steps of: 1. forming on a paper making screen, a wet base sheet of 35 felted fibrous material and prior to removal of said base 3. The process of claim I wherein the base sheet is paper. 40 45 50 55 60 I 65 70 o75 47 United States Patent Office 3,677,803 Patented July 18, 1972 12 ment, to prevent seizure of the fastening element to the 3,677,803 securing member. ANTISEIZE THREAD COMPOSITION A further object is to provide a process for treating Frank W. Bennett and Loren S. Van Delioder, Charles threaded steel members prior to engaging the nut or ton, W. Va-, assignors to Union Carbide Corporation, New York, N.Y. No Drawing. Original application Ang. 30,1968, Ser. No. 6 other fastening element thereto to prevent seizing of the nut to the threaded steel member. These and other ob 756,355. Divided and this application Mar. 5, 1971, jects will be apparent from the following description. Ser. No. 121,534 The antiseize material of the present invention is a InL CL B44d S/00,5/08 chrysotile asbestos, preferably a chrysotile asbestos which U.S. CL 117--94 11 Claims 10 has been comminuted into a fine powder and a carrier therefor, and which has been treated to remove gangue materials and other impurities. As is known, chrysotile ABSTRACT OF THE DISCLOSURE asbestos generally occurs in mineral deposits in the form An antiseize composition comprising finely divided of closely packed fibers. The process of separating the pulverized cbrysotile asbestos and a carrier therefor. There is also provided a process for treating metallic se 15 fibers from the asbestos ore in which they occur generally comprises a series of crushing and winnowing operations curing assemblies of the type wherein a metallic securing whereby the fibrous rock is subjected to mechanical pres member such as a stainless steel bolt tbreadably engages sure and shock, and during these operations the fiber is a fastening element such as a stainless steel nut to pre carried away by air currents and the associated rock is vent seizure of the fastening element to the securing 20 discarded. member at the site of threadable engagement which com For some commercial operations where the purity of prises applying the novel antiseize material to the por the product is not of substantial significance, the above tions to be in threadable engagement. procedure for producing a chrysotile asbestos has been found to be generally satisfactory. In many important 25 commercial operations, as well as in the present inven tion, however, it is preferred that the asbestos material This application is a division of application Ser. No. have a high degree of purity, that is, that the final product 756,355, filed Aug. 30,1968, now abandoned. contain little or no gangue or other impurities, and more The present invention relates to a process for treating over, that the fiber bundles be separated into individual metallic securing assemblies of the type wherein a metal lic securing member tbreadably engages a fastening ele 30 fibrils from each other. Several techniques have been proposed to chemically ment and more particularly to a process for treating bolts disperse the asbestos fibrils and thus obtain more com to prevent seizure of the bolts to the nut in threadable plete separation of individiftl fibrils from each other and engagement therewith. from gangue and other impurities. Such chemical disper Securing assemblies fabricated from metals such as steel and/or stainless steel bolts and nuts, threaded rods 33 sion techniques are described in U.S. Pats. 1,907,616; 2,661,287; 2,626,213 and 3,062,701, for example. and the like are currently widely employed in many A particularly suitable and preferred procedure for pre commercial and industrial applications. Their wide accept paring asbestos dispersions is described in U.S. Pat. 3.297,- ance is based primarily on the relative strength provided 516. Generally, the process described therein comprises by such metals, particularly steel and stainless steel assemblies, and also their resistance to many chemical 40 contacting an aqueous slurry of chrysotile asbestos with a metal aluminale such as potassium aluminate, calcium reactions. However, these securing assemblies, for exam aluminate or barium aluminate. To the slurry is added a ple, steel bolts when used at high temperatures, tend to monobasic acid, such as, acetic acid, formic acid, hydro weld to the nut with which it is in threadable engage chloric acid, or nitrous acid until the pH of the resulting ment so that either the threads are damaged during dis assembly or complete seizure occurs requiring that the 45 aqueous slurry is from about 4.0 to about 6.0. As a result there is formed a highly charged, strongly adsorbable, bolts be twisted or cut off. When employing austenitic polymolecular colloid of material consisting of aluminum stainless steel bolts, the problem is even more pronounced hydroxide or hydrated aluminum oxides. The slurry is in that seizure of the nut to the bolt can occur by galling thereafter subjected to high speed shearing forces to pro when the steel boll and nut assembly is made at ambient temperature. In order to alleviate this problem, it has 60 vide asbestos dispersions which are useful as a source of finely divided asbestos. Purification, i.e. separation of been the custom to apply a lubricant or anti-seize com gangue and other impurities can thereafter be easily ef pound to the threaded portion of the securing member fected by known gravity methods. prior to engaging the securing member with the nut or The chrysotile asbestos antiseize material can be applied other fastening element. The commonly employed lubri 65 to the threaded portion of the securing element in any cants or anti-seize compositions include greases, oils, convenient form such as in the form of powders, disper metallic compounds and graphite. Unfortunately, how sions, suspensions and the like. A particularly convenient ever, some of the above-mentioned materials are not en procedure is to utilize the chrysotile asbestos in the form tirely satisfactory for use at elevated temperatures and of a paste containing the chrysotile asbestos in finely di those which are suitable are relatively expensive and add to the cost of fabrication. 60 vided, pulverized form. Thus, when employing the abovementioned prior art procedures for preparing dispersions We have discovered an antiseize material, that is, a of the asbestos material, the aqueous dispersion can be material which prevents seizure and/or galling of the filtered thereby forming a "cake" of the asbestos material. fastening element to the securing member which material A liquid carrier, such as a paraffinic oil preferably mineral is inexpensive, easy to apply and which maintains its 66 oil, alkyl glycols, water and the like can then be added to property under severe conditions of elevated tempera form a paste-like consistency to the mass. In general, tures over extended periods of time. the chrysotile asbestos comprises from about 10 to about It is, therefore, an object of the present invention to 60 percent by weight of the weight of the composition, provide a new antiseize material. preferably 15 to 30 percent by weight. Thus the carrier Another object is to provide a process for treating 70 can comprise 40 to 90% and preferably 85 to 70% carrier. metallic securing assemblies, of the type wherein a metal In some cases the presence of alkali and/or chloride lic securing member tbreadably engages a fastening ele- contaminants in the asbestos can have a detrimental effect I 8,677, 803 3 on the material to be serviced. For example, the presence 4 In this example, the antiseize composition was tested of significant quantities of chloride in the asbestos could fat connection with one-half inch diameter by two-inch cause stress-corrosion cracking of austenitic stainless steels long, hex-head, coarse-thread, machine bolls of type 304 and the presence of alkali can have a detrimental afTect on stainless steel. Two nuts and two flat washers of the type iron fasteners. For this reason, it is preferred that these 5 304 stainless steel were placed on the threaded portion contaminants be removed from the asbestos. A convenient of each bolt. The antiseize material was applied by band and effective procedure for removing alkali and chloride to the threads of the bolt, and a nut was screwed on the from asbestos involves diluting the asbestos so as to obtaia bolt. The threads were again recoaled, the washers were above 2% solids by weight asbestos in distilled water or coated individually and placed on the bolt and the second deionized water. In this manner, the contaminants diffuse 10 nut thereafter screwed on the bolt. The nuts were there from the surface of the asbestos into the bulk water. after tightened onto the bolt with a torque wrench having Thereafter the bulk water is separated from asbestos by a a dial indicator reading of zero to 600 in.-lbs. (50 ft.- conventional filtration procedure. Ibs.) and were preloaded to 30 ft.-lbs. or 360 in.-lbs. tor The securing assemblies to which the present invention que preload. The nuts were loosened and a measurement is directed are those which normally are effected by 15 taken as to the amount of breaking torque required to changes in temperature, pressure, time and other variables loosen the nuts. The nuts were again tightened to 360 in.- which cause "seizing" of the assembly, e.g. the seizing of lbs. preload a second time and again loosened. The nuts the nut to a bolt were tightened to 360 in.-lbs. torque preload a third time Merely as illustrative, the antiseize material can be and thereafter exposed to a temperature of 1200* F. for effectively employed in connection with securing assem- 20 793 hours and the breaking torque after exposure was blies fabricated from iron, steel, stainless steel, nickel- again measured. The results are indicated in Table I. base alloys, cobalt-base alloys and complex super-strength stainless steel alloys and the like. The method for applying the chrysotile asbestos ma EXAMPLE 2 The procedure of Example 1 was repeated and the terial to the securing assembly can be varied and depends 25 results indicated in Table I. in part on the form in which the asbestos is to be applied. Where the chrysotile asbestos is the sole essential material i.e. without a carrier, such as finely pulverized chrysotile material in powder form, then a convenient procedure for EXAMPLES 3 AND 4 The procedure of Example 1 was repeated, except that the antiseize material was pulverized chrysotile asbestos application is to spray the asbestos material into the 30 which was present in an amount of 27.1% in water and threaded portion of the securing member. However, this the tests were conducted on two stainless steel bolts. procedure is not preferred because of the lack of ad The results of the foregoing Examples are indicated herence of the asbestos material to the securing member. in Table I and are compared with a control in which no This disadvantage can be minimized however by first antiseize material was employed. TABLE I.--8TAINLEEE STEEL BOLT ANTISEIZE TESTS AT 1.200* r. FOR 7 HOURS IH" dla. type 804 bolts with 2 nuts and 2 fiat washers, lubricant In threads and between washer? (SO tt.-lbs. or M0 tn.-lha. torque preload)] Breaking torque Immediately alter preloeding Eiample No. Autlselu materiel 1st preload 1................ .. 19.3% flufly ajbextoa In mineral oil. 2............... .. Same as Example 1..-- s................ .. 27.1% pulverized asbestos In water. 4.................. Bame as Example 8..^ Control__ .. Non*............................ 110 370 M0 ISO 290 2nd preload M0 890 410 430 too Breaking torque alter exposure Condition of material and bolt after exposure 423 Front nuts finger-loose after breaking, back nuts fairly loose. No galling. Soft, fluffy white coating, vary good lubricating "loel." 400 Same as Example 1. <00 Same as Examples l and 2 exoapt batter distribution and retention of coetlni in threads. 825 Eame as Example 8. >600 Galling occurred. * coating the threaded member with an adhesive prior to What is claimed is: / application of the chrysotile asbestos. ( 1. A method of treating metallic securing assemblies When the chrysotile asbestos is employed in the form \of the type wherein a metallic securing member thread- of a paste, the material to be serviced can be immersed in ably engages a fastening element to prevent seizure of the paste to the extent of the threaded portion or alterna 66 the fastening element to the securing member at the site tively the paste can be applied by rubbing the paste onto the of threadable engagement which comprises applying to surface of the threaded portion of the securing member. . the portion of the securing member to be threadably It will, of course, be understood that the antiseize mate engaged with said fastening element a chrysotile rial can also be applied to the threaded portion of the fastening element in lieu of the above or in addition to 60 asbestos. 2. A method according to claim 1 wherein .. aald the above that a variety of techniques can be employed chrysotile asbestos is applied in the form of a paste com for this purpose. prising 15 to 30% chrysotile asbestos and 85 to 70* of The invention will be more fully understood by refer a carrier therefor. ence to the following specific examples. These examples 05 3. A method according to claim I wherein said are merely illustrative of the practice of this invention chrysotile asbestos is applied in the form of a paste and are not intended to limit the invention in any manner other than as defined in the appended claims. comprising 10 to 60% chrysotile asbestos and 40 to 90% of a carrier therefor. EXAMPLE 1 4. A method according to the claim 2 wherein aald The chrysotile asbestos employed in this example was 70 carrier is water. in the form of a heavy paste containing high-purity, 5. A method according to claim 2 wherein said car resin-grade, short fiber white asbestos sold by the Mining rier is an alkyl glycol. & Metals Division of Union Carbide Corporation. The 6. A method according to claim 1 wherein said paste contained 19.3% chrysotile asbestos and 80.7% securing assembly is fabricated from stainless steel. mineral oiL 7* 7. A method according to claim 1 wherein said 1 uo49 3,677,803 6 metallic securing member is a steel bolt and wherein said 6 10 wherein said aecuring member is a bolt and said fastening element is a stainless steel nuL fastening element is a nut. 8. A method according to claim 2 wherein said chrysotile asbestos is a finely divided, pulverized chiysotOe References Cited asbestos. 9. A metallic securing assembly comprising a securing member in threadable engagement with a fastening ele ment and a chrysolite asbestos disposed at the site of said 5 UNITED STATES PATENTS 2,419,252 4/1947 Bychinsky et al. .. 117--127 X 3.061,455 10/1962 Anthony117--127 X threadable engagement. 10. A metallic securing assembly according to claim io EDWARD G. WHITBY, Primary Examiner 9 wherein said securing member and fastening element is fabricated from stainless steel. U.S. Q. X.R. 11. A metallic securing assembly according to claim 85--1 C; 117--121, 135.1, 169 R; 252--14, 28 United States Patent Office 3,838,085 Patented Sept. 24. 1974 12 degradable thickeners such as cellulose ethers. Further more, since the pigmented asbestos is a less costly prod PIGMENTED ASBESTOS LATEX EMULSION uct than pure pigment, the cost of manufacture of the I PAINT COMPOSITION paint can be significantly reduced. Jobs L. Myers, Lewiston, 'N.Y., and Richard W. Lasher, Palos Verdes. Peninsula, and Rusell D. lames. La 5 Pat. No. 3,328,238 to Knowles et tl. discloses stable sus pensions of organic or inorganic fibers, including asbestos Mirada, Callf-7 assignors lo Union Carbide Corpora tion, New York, N.Y. Continuation-in-part of abandoned application Ser. No. 14,796, May 5. 1970. This application Oct 24, 1972, fibers, in a hydrocarbon vehicle, for use as propellant sus pensions, agricultural compositions, oil base drilling fluids, and oil base paints. In the latter application the micro Ser. No. 300,193 10 fibers act as a suspending matrix for the pigments in the Int CL C08f 45/24 paint, forming a fibre thickened vehicle or gel in which U.S. CL 260--29.6 R 16 Claims the pigment solids are dispersed. However, this patent bears no relation to and does not suggest the aqueous latex emulsion paint composition of the present inven ABSTRACT OF THE DISCLOSURE 15 tion in which the high purity chrysotile asbestos fibers hav Premium latex paints are disclosed exhibiting superior ing certain physical characteristics are predispersed in opacity and brightness characteristics, including dispersed water to develop a cationic charge so as to electrostatically and liberated short chrysotile asbestos fibers having ani onic pigment particles electrostatically attached at dis bond anionic pigments to the asbestos fibers, to form the pigmented asbestos of tbe invention, as described in de crete points along the length of the fibers. 20 tail below. Tbe above and many other attendant advantages of the invention will become apparent as the invention becomes This application is a continuation-in-part of copending better understood by reference to tbe following detailed application Ser. No. 34,796, filed May 5, 1970, now description when considered in conjunction with the ac abandoned. 25 companying drawings wherein: The present invention relates to pigment dispersions and FIG. 1 is an illustration of the appearance of dry proc coating compositions and, more particularly, to latex essed Calidria fibers, one form of high purity crysotile paints including a dispersion of pigmented asbestos fibers. asbestos fibers, at 20,000 magnification; High quality finish paints include hiding pigments such FIG. 2 is an illustration of the appearance of wet proc as rutile titanium dioxide (TiOj) which have a high re 30 essed Calidria fibers; fractive index (2.7) compared to the other ingredients in FIG. 3 is a flow chart illustrating alternative processes the system. Opacity, or hide, is a function of the differ for forming pigment dispersion; ence in refractive index between the TiOa and the pig FIG. 4 is an illustration of pigmented liberated fibers ment binder (l.S). The different refractive indices cause of FIG. 2; and the incident light to be bent through a succeeding series of 35 FIG. 3 is a graph illustrating the relationship between angles within the coating by alternately striking pigment tbe solids content of refined asbestos filter cake and degree binder, then titanium dioxide. The ultimate result is to of pigment dispersion in terms of National Standard reflect the incident light ray. (N.S.) Grind Numbers. To optimize this mechanism within a coating system, It has been discovered in accordance with the inven the titanium dioxide must be thoroughly dispersed. Pres 40 tion that the above advantages are obtainable with particu ently, high speed dissolvers are employed to impart ex lar forms of asbestos having certain surface area, lengths, tremely high rates of shear to disperse the titanium diox fiber availability, and very high cationic charge density. ide. Surface active agents aid the process by lowering the Tbe high charge density and liberated form of the fibers surface tension of the liquid medium in which the pig allow the fibers to electrostatically bond firmly to ani ments are dispersed, and help keep the pigments separated 45 onic pigment which satisfies the charge to form a highly once the shear is stopped. However, it has not been possi pigmented fibrous product. By the term "liberated" fibers ble in practice to completely disperse the pigment par or fibrils is meant that such fibers are in the form of ticles which tend to agglomerate and reduce the optical discrete fibers or fibrils, rather than in tbe form of fibril efficiency of the paint film. bundles. Without the electrostatic bonding of the pig In accordance with the present invention, unproved pig 60 ments to tbe fibers to satisfy the cationic charge oo tbe ment dispersions and paint compositions are prepared by fibers, tbe available cationic charge on the fibrils reacts dispersing and firmly holding the pigment particles along with and agglomerates anionic latex particles. Without the length of liberated, i.e. discrete, highly cationic, col the cationic fibers, the anionic pigments will tend to ag loidal, short fiber, high purity asbestos fibers. When aque glomerate, reducing optical efficiency. When these materi ous pigment dispersions containing such pigmented as bestos are incorporated into paints, the resulting film 65 als are combined according to the invention, the pigment is uniformly distributed along the length of the fibers so exhibits an increased opacity and has several other un that the final product resembles and performs like a fibrous expected effects. pigment. The uniform distribution of the pigmented Even though the asbestos itself is a gray dull material fibers results in a very high optical efficiency and therefore and has a fairly low brightness, unexpectedly the paints less hiding pigment is needed to obtain a given opacity. incorporating the aqueous pigment dispersions according SO Pigment dispersions in accordance with the invention to the invention have very high brightness levels. It has incorporate a particular type of high purity chrysotile further been surprisingly discovered that although asbes asbestos. Generally, chrysotile asbestos has a low index tos usually occurs as lumps which would prevent the dis- of refraction of about 1.31 to 1.33, is the softest and persability and a fine grind, a very fine finished aqueous latex paint having dispersed solids of a grind or fineness 05 most flexible of the several types of asbestos. When dis persed in water it exhibits a positive or cationic surface below 2 mils, can readily be manufactured from the aque charge and a very high tensile strength. Chrysotile asbestos ous pigment dispersions containing the pigmented asbestos occurs only in serpentine, a fine grained rock composed fibrils in accordance with the invention. entirely of hydrous magnesium silicate minerals similar The pigmented asbestos of the invention in addition to chrysotile in composition. Most deposits of serpentine provides improved structural strength to the film and also, w contain chrysotile in cross-fiber veins, and the ore typi can decrease or eliminate the necessity for the use of bio- cally contains only 6 to 10 percent fiber of random lengths A 0S5 1 t 8.838,085 3 4 which tre tightly bonded together in a parallel configura The virtue of their small diameters and high aspect tion. ratio, tbe high purity chrysotile, asbestos fibrils form col The unique materials according to the invention bear loidal suspensions when suspended in water and behave ac little resemblance to other serpentine bodies since most cording to the classical electrokinetic rules of hydrophobic of the mass of fibers are highly sheared and pulverized and g colloids. That is. the fibrils develop a surface charge when consist of soft, friable sheets and clumps of asbestos fiber. suspended in aqueous solution as the result of adsorption In contrast to the cross-fiber arrangement of conven of potential determining ions from the ausepnding me tional Canadian ores, the high purity chrysotile asbestos dium. The potential determining ions are mainly hydro material, one form of which is marketed as Calidria as gen, and therefore, the fibers display a positive charge in bestos fibers, and is preferred for use in the present inven- jo the basic pH range. Thus, the term "cationic" asbestos as lion, is obtained from a deposit near Coalinga, Calif., employed herein is intended to denote asbestos or asbestos occurs as a swirling mesh of disoriented fibers. fibers which exhibit a cationic charge when dispersed in Conventional asbestos processing methods include blast water under tbe pH conditions, usually about 4 to about ing. crushing and grinding, and air classifying. Even with 9.5, generally used in the paint industry. Electrostatic at the use of the very best dry method of processing high 15 traction, however, is just one of the factors that influence purity chrysotile asbestos ore, fiber bundles are still very tbe effectiveness of the fibers in coffoccing pigment par much in evidence as shown in FIG. 1. The high purity ticles. Collision and coagulation rate in suspension are de chrysotile asbestos utilized in the present invention is termined by tbe collision radius which varies as tbe long preferably refined in accordance with a hydraulic bene est dimension of the panicle while diffusion constant fication process to provide substantially separated fibrils gg varies as the main particle dimension. Tbe net result 10 as shown in FIG. 2. In the hydraulic beneficiation for (he rod-like, high purity chrysotile asbestos particles process, the ore is treated by wet grinding and screening is a very Urge effective collision radius and a large dif to separate rock from asbestos fiber, flakes and clumps. fusion constant. Furthermore, the high surface area of The asbestos is then subjected to wet mechanical and/or the high purity asbestos fibers, ranging from about 60 to chemical treatment to liberate the fiber, that is, to sep- gg 80 meters'/gram, in combination with the cationic charge arate the fibers into discrete fibers, and separate out oc provides a very high cationic charged density for attracting cluded non-asbestos minerals to form standard grade prod and firmly holding the pigment panicles. uct High purity product is obtained by further wet grind The high purity chrysotile asbestos can be provided in ing and centrifugal processing of the standard grade prod several forms, particularly useful in forming the pigment uct. This process results in separated, individual or discrete go dispersion in accordance with the invention. The final form fibers of high purity, high liberation and uniform par of the fiber in the pigment dispersion is preferably a total ticle size. Thus, this asbestos is different from any other ly liberated, colloidal form. This is usually achieved with asbestos product available. The physical properties of tbe particular high purity, sbon fiber chrysotile asbestos average Canadian, standard grade Calidria and high purity of interest which has an ultimate fiber yield of at least Calidria asbestos are provided in the following table. gg 85%, e.g. 85-95%. Canadian chrysotile asbestos fibers, PHYSICAL PROPERTIES OF CBRYBOTILE ASBESTOS as represented by Canadian 6-D-20 (see Example DC) is CsUdrla products Property Avs*e Sundud Canadiantrade High pufliy Burtece area, m.'ft...................... ReSeclaDOt, percent...................... Magneute, percent........................ 10-10 H-70 S-6 SO-SO 82-72 2.0 SO-SO 72-76 <0.80 only liberated to an extent of about 25-40% ultimata fiber yield under tbe same conditions. Ultimate fiber yield is determined by pulping 3 grams asbestos in 250 ml. of tap water at high speed in a Waring Blender for 3 minutes. The pulp is washed into a beaker to 8 final volume of 300 ml. The pulp is dispersed, de canted, flocculated, dried and weighed. Percent ultimate Specific surface area is calculated from adsorption data fiber yield is the supernate chrysotile asbestos filter cake using the BET (Bruoauer, Emmet, Teller) method as de- 45 weight times 3 divided by the total weight of tbe two cakes scribed in Brunauer, "The Adsorption af Gases and times 100. Vapors," Princeton University Press (1945). The filter cake of liberated asbestos fibers in accordance Magnetite content is measured by a permeametric de with this invention is a lightly compacted, essentially non vice patterned after ASTM standard method I>-1118-57, agglomerated product which is readily redispersible in which has been improved with respect to sensitivity to 60 water with conventional mixers to form an aqueous dis measure a limit of detection of 0.005% magnetite. persion containing liberated fibers. Reflectance is measured on a sample prepared accord In the first step of making a high quality paint formu ing to TAPPI (Technical Association of the Pulp and lation in accordance with the invention, a dispersion of Paper Industry) standard T-452-m-58 and is reported as pigments is prepared. The pigment dispersion can contain percent of ultimate reflectance based on magnesium oxide 65 varying amounts of tbe pigmented asbestos usually rang as the standard of 100% reflectance. ing from 1% to 25%, preferably 5% to 10%, of the total The significantly greater purity of the high purity solids of the dispersion, depending on the water demand chrysotile asbestos essential in this invention is demon of the various components of the system, the properties strated by its improved reflectance of at least 72% and its desired for the final paint composition and properties de low magnetite content of less than 0.8% magnetite. The 60 sired for the final paint film. The unpigmenied high purity wet processing procedure gives rise to high purity asbestos chrysotile asbestos fibers have a water demand of about fibers that are essentially grit-free and of high brightness. 480% while the pigmented fibers have a lower water de The reduced magnetite content of the pure flake product is mand depending on the quantity and type of pigment. also a measure of absence of gray appearance that has The demand for pigment in terms of cationic charge it been characteristic of prior asbestos products. The re- 65 preferably completely or totally satisfied by anionic pig dUced grayness and absence of black specks is essential in ments. The high purity chrysotile asbestos fibers develop a the preparation of premium quality finished paints. total positive charge which must be completely balanced The individual asbestos fibers are in the form of slight by combining with a total negative charge which is fur ly-curved, short tubes having an external diameter of nished by the anionic pigment, resulting in electrostatic about 260 A. and an internal diameter of about 110 A. 70 bonding of anionic pigment along the length of its fibers. The length of the fiber varies from about 100 to 1,000 It has been found that in order to completely satisfy the times the diameter and the average L/D ratio is about 200. cationic charge on the asbestos fibrils, it is necessary to Thus, tbe average fiber length is about 5 micron and it is employ a ratio of at least nine times anionic pigment to estimated that there are about 1014 fibrils in one gram of asbestos, by weight. Thus, in totally liberated or discrete the high purity chrysotile asbestos. 7^ fprip, the^asbestos fibers or fibrils can cofloc or satisfy i odd2 A 5 68,838,085 bout 9 to 10 times the weight thereof with aniooic pig- form filter cake containing 40-60% asbestos fiber which ment. Buy be optionally dried with tumbling in a rotary drier The fibers may be totally pigmented with a primary to a homogeneous product having a solids content of 80- hiding pigment having high efficiency and providing 90% asbestos. Again, the pigment dispersion can be opacity such as rutile titanium dioxide. Anatase titanium g formed by adding the total pigments at one time to the dioxide may be used where chalking is desired. Other dispersion of fibers, with blending or separately predis- anionic hiding pigments comprise zinc sulfide, zinc oxide, persing the hiding pigment such as rutile titania before basic silicate of white lead, lithopane, iron oxide or anti- adding the remaining pigments and blending to form the mony oxide. Any combination of these hiding pigments pigment dispersion. may be utilized. In another procedure in accordance with jo A series of experiments were run to determine the criti- the invention to be discussed below, the fibers may be cal percent fiber that could be provided in a reduced water pigmented with a mixture of anionic hiding pigments or content chrysotile asbestos filter cake that is readily div a mixture of anionic hiding and extender pigments. Typi- persible with conventional mixers available to most paint cal extender pigments and the amounts in percent by processors, rather than the high shear and high horse* weight in which they may be present are provided below, jg power mixers necessary to completely disperse the pre- These extender pigments may be combined as desired for titanaled pellets. Standard interior latex paints were pre* a particular end result. pared according to the formulation of Example 4 with 1. Calcium carbonate (whiting) 0 to 25% SSlSnimhi?^'Ft""'?* UbU'a`ed '** 2. Hydrated aluminum silicate (clay) 0 to 25% following table and Flu. 5. 3. Magnesium silicate (talc) 0 to 8.5% *0 TABLE II.--LATEX PAINT CONTAINING 4. Silicon dioxide and calcium silicate (silicas) 0 to 4.5% FILTER CAKE 5. Potassium aluminum silicate (micas) 0 to 6.5% Latex Paint of 6. Other pigments including barium sulfide, bentonite, FilteT Cake_ Example 4--National magnesium aluminum silicate and various organic and inorganic and crystalline pigments. Asbestos Weight Percent 41 Standard Grind No. 6 \ The hiding pigment such as titanium dioxide, and the extender pigments such as clay and calcium carbonate, exhibit an anionic or negative charge when dispersed in water as result of attachment of hydroxyl groups to the 30 55 ---------------------------------------------------------------------- 5.6 75 ----------------------------------------------------------------------4-5 -------------------------------------------------------------------4.5 ------------------------------------------------------------------- * pigment, and hence are termed "anionic" pigments herein. Wrinkling was evident at about 91% solids level in Total pigment present in the paint composition of the the filter cake, and above, indicating incomplete fiber invention can range from about 4 to about 65% by liberation and therefore the presence of available cationic weight. Anionic hiding pigments are present in an amount charge which causes coagulation of the anionic latex, generally of about 4% to 25% by weight, or higher. The 35 Unexpectedly, the filter cake can be dewatered to a preferred hiding pigment due to its efficiency in providing ]evel as high as about 91 % by'weight of asbestos and still opacity is rutile titanium dioxide. Other hiding pigments maintain an adequate grind of 4.5, corresponding to less noted above may be present to replace a part or all of the than 2 mils, in the resulting latex paint, indicating fairly rutile titanium dioxide. good liberation and noncompaction of the fibers into bun- Referring now to FIG. 3. several processes for forming 40 dies. It is however, preferable to maintain the asbestos pigment dispersion containing coflocced pigmented as- content of the filter cake from about 80 to 90% to provide bestos are illustrated. In the pellet or open fiber process finer fin;sh pajnt fi|ms. The 80 to 90% asbestos filter cake (1). a dilute liberated asbestos slurry such as a slurry con- product affords substantial absence of wrinkling as well taining 2.5% asbestos is blended with an anionic hiding _ a$ adequate grind of less than 2 mils for the latex paint pigment such as rutile titanium dioxide. Oppositely 43 |n which such filter cake is incorporated, and is otherwise charged asbestos fibers and titania particles are attracted a very desirable commercial form of asbestos since the and bond to each other to form a coflocced product as water content thereof is sufficiently low to minimize ship- illustrated in FIG. 4 which shows the fibrils 10 having pjng costs and it is a form readily available for dispersion, particles of titania 12 electrostatically attached along the The dispersion containing the dispersed pigmented as- length of the fibers to form a predispersed product. In the 50 bestos is incorporated into a latex paint which is defined pellet, and open fiber process, the ratios of materials are as a paint in which water is the principal diluent. The adjusted to form a product containing from 1 to 90% nonvolatile portion of the paint is between 30 and 80% titania, suitably about 35% titania, though the asbestos while the pigment volume concentration (PVC): is capable of holding up to 9 times or more, e g 9 to 10 times, its own weight of pigment. The coflocced slurry is 65 _________pigment volume________ VI00 dewatered, extruded into pellets and dried in a rotary pigment volume + vehicle volume dryer. The dried pellets can be milled to form an open is between about 15% and 80%. The paint may optionally fiber form of the product. also contain binders, solvents, thickeners, surfactants and The paint formulator may predisperse the pellets or. various other additives. Exemplary materials for each open fiber in water with a high shear mixer to form a 60 component with a suggested percentage basis based on liberated slurry of the partially titanaled asbestos. The the total weight of the paint are provided below. These remaining pigments are then added, continuing the high ingredients are understood to be exemplary and are not shear mixing to form the final pigment dispersion. The intended to any way limit the invention, it being under- separate dispersion in water with high shear mixing better stood that alternate materials can readily be substituted assures complete liberation of the fibers, to form a paint G5 for those suggested. having a fine grind. Alternately, the remaining pigments A general procedure for formulating paint compositions in water can be added directly to the pellet or open fiber, according to the invention is to first charge all liquid and mixed with high shear to form the pigment disper- ingredients including optional thickeners, and optionally sion. The dispersion of the high purity chrysotile asbestos including a portion of the vehicle, especially in the case is materially aided by reducing the pH of the slurry to 70 of modifier vehicles. The charge is thoroughly mixed and the acid range, preferably from about 4-5. An electro- the solids namely, the anionic pigment and cationic as- static condition in the slurry under these conditions pre- bestos fibers, are then added under high shear dispersion, vents lbe fibers from reagglomerating. In the case of anionically charged vehicles, such as an- In the filter cake process, (II), the dilute liberated as- ionic resins, the presence of the cationically charged as bestos slurry is dewatered in a vacuum frame press to 75 bestos renders it necessary for prepigmentization of the A ; 055 3 8,838,085 asbestos to completely satisfy this cationic charge, before addition of the anionic vehicle; otherwise, coagulation saturated polymerizable vinyl group. The polymer func tions to bind the pigment particles together and to bind of the anionic resin will occur as result of the combina the paint film to the substrate. Generic types of suitable tion of anionic resin with unsatisfied cationic charge on latex emulsions and polymers are listed below: the asbestos. Nonionic vehicles, e.g. nonionic resins, can g 1. Polyvinyl acetate homopolymer latexes. be udded at any stage of the manufacture. 2. Vinyl Acetate--acrylic copolymer latexes. The The diluent concentration is preferably maintained be acrylic portion includes but is not limited to ethyl acryl tween about 20 to 70%. While water is the primary and ate, isobutyl acrylate, methyl methacrylate, N-butyl predominant diluent in a latex paint system, solvents for acrylate, methacrylic acid, N-methylol acrylamide, modifying resin vehicle may also be present. The per- jo acrylonitrile, 2-ethyl hexyl acrylate, and acrylic acid. ccntage range also includes the water present in such Furthermore, these ctpolymers may contain itaconic vehicle portion. acid, styrene, butadiene, ethylene, vinyl chloride, Substantial thickening of the paint is provided by the maleates, and fumarates. Specific examples of such poly fairly high water demand of the asbestos. In some cases, mers are the copolymer of vinyl acetate and butyl acry secondary thickeners need not be present. However, in 15 late, vinyl acetate and 2-ethylhexyl acrylate, vinyl acetate most cases, the viscosity of the paint can be adjusted to and dibutyl maleate. the desired range of 60 to 125 K.U. preferably 80 to 105 3. Acrylate Latexes--The acrylate latexes may contain K.U., by including 0 to about 4% of conventional thick any combination of acrylate and acrylic monomers noted eners such as water soluble cellulose derivatives, e.g. cel above in vinyl acetate-acrylic latexes, except for vinyl lulose ethers or esters, for example, hydroxyethyl cellu- 20 acetate. Specific examples of such polymers are the co lose, methyl cellulose, and carboxymetbyl cellulose. Other polymer of ethyl acrylate, methyl methacrylate and meth types of materials can also function as thickeners such acrylic acid, and the copolymer of butyl acrylate, methyl as carboxylated polyacrylic acids, sodium alginate, ben methacrylate and acrylic acid. tonite clays, a polymethylvinyl ether reaction product 4. Other latexes include polymers of styrene-butadiene, with maleic anhydride, and polysaccharides. The expres- 25 styrene-acrylic, acrylonitrile-butadiene rubber, butadiene sion "K.U." refers to Krebs units, a measure of viscosity rubber, and ethylene-vinyl acetate, vinylideDe-cbloride, which is conventionally used in the paint industry, and and acrylate-vinyl chloride polymers. is determined with the Krebs-Siormer viscometer, as de It will be understood that the proportions of comono scribed in the brochure of the Arthur Thomas, Co., Phil mers in the above described copolymers can be varied adelphia, Pa., "Directions for Use of Stormer Viscosim- 30 as desired and as well understood in the art, to obtain eter," published 1948. the desired properties. Thus, for example in the copolymer Surface active agents which function as surfactants and of vinyl acetate and butyl acrylate the monomer propor dispersants can be present in the range of about 0.1% to tions can range from 90 to 75% vinyl acetate monomer 4% by weight of this composition. These ingredients wet and 10 to 25% butyl acrylate monomer; and in the co the surfaces of the particles and stabilize the emulsion 35 polymer of ethyl acrylate, methyl methacrylate and meth or colloidal system. Usually only anionic and nonionic acrylic acid, the proportions of monomers can range from compounds are utilized in latex paints and preferably a 40 to 70% ethyl acrylate, 20 to 35% methyl methacrylate mixture of these types of surfactants is utilized. Many and 0.5 to 3% methacrylic acid. diverse types of surfactants which are commonly used Latexes containing combinations of the above resins in the formulation of latex paints are suitable for use in 40 can also be employed, such as a combination of vinyl forming the pigmented asbestos latex paints in accordance acetate homopolymer and copolymer of vinyl acetate and with the invention. butyl acrylate. Exemplary anionic surfactants are saponified fats, sul- The resins in the above latexes in the presence of fonated materials such as fatty acid esters, monovalent anionic surfactants generally achieve an anionic charge. alcohol esters of fatty acids, fatty acid amides, fatty acid 45 This is due to the polymerization of the monomers to nitriles, fatty aldehydes, secondary alcohols, or aromatic form the resins, in the presence of such surfactants carry hydrocarbons. Other suitable anionic surfactants are al ing an anionic charge. Polymerization can also be achieved kali sulfonates of alcohols having 6 or more carbon at in the presence of nonionic and cationic surfactants, in oms, aminopolycarboxylic acids and the condensation which case the resulting resins are either nonionic or products of fatty acid chlorides and amines. 60 cationic in nature. However, because of the cationic There are fewer non-ionic compounds commercially charge of the chrysotile asbestos fibers, the anionic latexes available. Exemplary non-ionic surfactants are saponines generally employed to the major extent in latex paints, and their derivatives, the condensation products of ethyl must be added to the dispersion of the chrysotile asbestos ene oxide with fatty acids and their derivatives or with fibers after addition thereto of the anionic pigment in phenolic compounds having a side chain. 65 order to completely satisfy the cationic charge of the Coalescing agents can be provided in an amount of 0 fibers with the anionic charge of the pigment, prior to to 4.5% as needed. Coalescing agents aid in film forma addition of the anionic latex, to avoid coagulation, as tion during the drying cycle. They Bre solvents for the noted above. vehicle and eventually evaporate from the paint film. Any of the above latexes may be modified with or Typical coalescing agents include plasticizers such as di- 00 ganic solvent based binders or oils which may be of the butyl pbthalate, glycols like hexylene glycol, glycol-ethers, drying or nondrying type. These modifiers in turn may be and certain alcohols. emulsified. Modifiers may comprise from 0 up to 70% of Freeze-thaw stability is an important property for the vehicle solids in a given paint in which water is the paints stored in cold climates. Glycols such as ethylene principle diluent. Suitable modifiers are the oils such as glycol, diethylene glycol and propylene glycol are added C5 linseed oil, tung oil. safflower oil, tall oil rosins or tall in an amount of 0 to 4.5% to insure freeze-thaw stability. oil esters. Resin modifiers comprise alkyd resins, epoxy Latex emulsions, e.g. an anionic, nonionic or cationic resins, vinyl resins, acrylic resins, silicone resins, phenolic latex, and various modifiers therefore, can be provided resins, ester gums and cellulose resins. in an amount providing about 5% to 50%, preferably Various miscellaneous ingredients may be present in about 5% to 25%, by weight of resin solids in the paint 70 an amount of 0% to 4% by weight. Included in this composition. Latex emulsions can be comprised of many category are defoamers which may or may not contain polymer types, and commercially available emulsions con silicones and fungicides, of the mercuric and non-mercuric tain 30% to 70% by weight resin solids in the form of types. Driers for the solvent based modifier such as co nonvolatile polymer. The polymer generally employed balt, zinc or magnesium naphthenates or phtbalates may according to the invention contains an ethylenically un- 75 also be provided when needed. Other various materials 8,838,085 9 10 may be incorporated for special purpose* at art well Material: Pounds known in the art. NOPCO NXZ 2 Generally the paint composition of the invention in CMP Acetate____ ___________ 0J cludes, in addition to the dispersion of the pigmented Ti Pure R-960 242.5 asbestos and latex, additional optional components, par 6 ticularly thickener, surfactant, e.g. anionic surfactant and ASP 170 Clay 100 VICRON 25-11 144.7 coalescing agent. Water 151 A aeries of paint formulations were prepared by first NOPCO NXZ 2 charging in order, water, thickener, surfactant, fungicide, NAT-l (55%) 287 freeze-thaw additive, coalescing agent, and about Vi of 10 the defoamer, and mixing for 5 minutes at low speed. Total 1202.9 Thereafter, tbe TiO, was added and dispersed until a desired dispersion was achieved. Mixing speed was in EXAMPLE II creased. Tbe remaining pigments, including calcium car Material Pounds bonate, clay and the high purity chrysotile asbestos fibers, 15 Water 306 were then added and mixed at high speed to form a pig Bentone LT 4.3 ment-asbestos fiber dispersion. The latex and remainder TAMOL 731--25% Active________________ 3 of the defoamer were then added to the pigment-asbestos VICTAWET 35B 5.7 fiber dispersion at low speed. Agitation should be con ADVAWET 33 4 tinuous and each ingredient dispersed before the next is 0 Ethylene Glycol___________ __ ____ 15 added. Butyl Carbitol Acetate 15 The chemical identification of each ingredient by type, NOPCO NXZ 2 formula and function is provided wherever possible. The CMP Acetate 0.5 asbestos utilized in each case, except for Example 9, was Ti Pure R-960 225 high purity, short fiber chrysotile asbestos in the form 25 of Caiidria asbestos as either dispersed unpigmented filter ASP 170 Clay 100 VICRON 25-11 112 cake or in pretitanated pellet form, as indicated. The CG 135........ 50 ingredients utilized in the formulations are provided in Water ................................................................... 131.5 the following table, and the examples follow thereafter. NOPCO NXZ 2 30 NAT-1 (55%) 287 Total 1263 TABLE m Function Material Generic type Solvent.................... Water.....................H0. 35 Materia] EXAMPLE III Pounds Thickener......... ...... Beotone LT______ Organically modified beulonlte. Anionic eurtaetant.. TAMOL731......... Sodium ialt of diisobutylene Water ____________________________ Bentone LT 4.3 maleic anhydride. TAMOL 731--25% Active________________ 3 Do.....................VICTAWET S5B. Sodium octyl phosphate. Konionlc ADVA WET S3... Polyglycol cater, 40 VICTAWET 35B 5.7 lurlartant. ADVAWET 33 4 Freete-thaw............ Ethylene glycol... Coalucent.............Butyl carbltol Monoether of diethylene Ethylene Glycol 15 acetate. glycol. Detoamer................ NOVCO NXZ.... 0.1% SI. Fungicide................CMP acetate........... Chloromethoiy-acetoxy Butyl Carbitol Acetate 15 NOPCO NXZ 2 mercurtpropane. Hiding pigment___ Tl pure R-900____ TIO,. Eilender pigment.. ASP 170 clay........ Kaolin clay. 45 CMP Acetate 0.5 Ti Pure R-960 ______________________ Do.....................V1CRON 2S-11... Calcium carbonate. ASP 170 Clay 100 Extender pigment, CO 100..................High purity chryeotlle. asbestos VICRON 25-11 112 Extender pigment, CO 1X5........ ......... Blgh purity chryaoUle, plus CG 135 (51%).................................................. 98 Utanated asbestos. 15% TIOi. Extender pigment, COW................40 to 50% solids. 60 Water 83.5 filter rake. Extender pigment, CO U5..................40 to S5% solids. Utanated filter NOPCO NXZ...................................................... 2 NAT-1 (55%).................................................... 287 cake. 6oleent............... Water.....................HiO. Dcfoamera............... NOPCO NXZ.... Total ------------------------------------------------------ 1263 Latex emulsion____ NAT-1 (55%)......... Copolymer of vinyl acetate and butyl acrylate (anionic). 65 Do.... ................ UCAR-U0 (58%). Vinyl acetate homopolymer EXAMPLE IV (nonlonlc). Do.......... ........UCAR-470 (48%). Acrylic emulsion containing Material Pounds copolymer of ethyl acrylate, methyl methacrylate, and metharrvUc arid (anionic). Water _____________________________ _______ 313 Bentone LT________________ _______________ 4.3 0.1 modifier..............PVO-44 (65%).... Bodied safflower amulaion. Eposy modifier....... Polrtfx 611 Q..........Epoxy ester emulsion. Thickener................CellosixeQP-WOt. A hydroxy ethyl cellulose. SO TAMOL 731--25% Active________________ VICTAWET 35B 3 5.7 ADVAWET 33 4 Ethylene Glycol 15 Butyl Carbitol Acetate 15 65 NOPCO NXZ 2 EXAMPLE I Material: Pounds Water..................................................................... 225 Bentone LT_____________ 5.5 70 TAMOL 731--25% Active.............................. 3 CMP Acetate 0.5 Ti Pure R-960 ..................... ASP 170 Clay____________________ VICRON 25-11.................................................. CG 100 (46.5%) Water 85............................................................. 242.5 100 112 70 85 VICTAWET 35B............................................... ADVAWET 33 Ethylene Glycol 15 5-7 4 NOPCO NXZ 2 NAT-1 (55%).................................................... 287 Butyl Carbitol Acetate'____________________ 15 75 Total .............. ............................................... 1263 306 225 h GG5G 11 EXAMPLE 1VA Mnterii] Water _________________ TAMOL 731--25% Active VICTAWET 35B------------ADVAWET 33-------..... Ethylene Glycol-------- -----Butyl Carbitol Acetate .... NOPCO NXZ____________ CMP Acetate-----------------Ti Pure R-960 ---------------ASP 170 Clay-----------------VICRON 25-11--------------CG 100 (46.5%)------------Water .................... .............. NOPCO NXZ-----------------NAT-1 (55%)---------------- Total EXAMPLE V Material Water ................................... Bentone LT _________ ..... TAMOL 731--25% Active VICTAWET 35B------------ADVAWET 33 --------------Ethylene Glycol--------------Butyl Carbitol Acetate____ NOPCO NXZ...................... CMP Acetate____________ Ti Pure R-960 ----------------ASP 170 Clay-----------------VICRON 25-11--------------CG 100 (46.5%)------------Water ___________________ NOPCO NXZ____________ NAT-1 (55%)----------------PVO-44 (65%)--------------- Total _________________ EXAMPLE VI Material: Water _______________________ Bentone LT--------------------------TAMOL 731-25% Active .. VICTAWET 35B------------------ADVAWET 33--------------------Ethylene Glycol--------------------Butyl Carbitol Acetate ....... NOPCO NXZ________________ CMP Acetate________________ Ti Pure R-960 ........................... ASP 170 Clay ........................... VICRON 25-11--------------------CG 100 (46.5%)------------------Water ----------------- ------------------NOPCO NXZ________________ NAT-1 (55%)----------------------Polytex 611 Q (60%)------------ Total............................. .......... 8,838,085 12 EXAMPLE Vn Material: Pounds Pounds 243 Water 315 Benlone LT .......................... 4.3 3 6.9 4.8 15 IS 2 0.5 10 242.5 100 93.7 TAMOL 731--23% Active----------------------VICTAWET 35B ADVAWET 33 Ethylene Glycol IS Butyl Carbitol Acetate __________ ____ _____ NOPCO NXZ 2 CMP Acetate 0.5 Ti Pure R-960 242.5 ASP 170 Clay 100 3 3.7 4 15 107.4 40 IS VICRON 25-11 112 CG 100 (46.5%)____ _____________________ 70 2 285 Water 100 NOPCO NXZ 2 UCAR-130 (58%) 272 1160.8 20 Total EXAMPLE Vm 1263 Material: Pounds Pounds Water 315 315 Bentone LT______________________________ 4.3 4.3 6 TAMOL 731--25% Active________________ 3 3 VICTAWET 35B 5.7 5.7 ADVAWET 33 4 4 Ethylene Glycol___________________________ 15 15 Butyl Carbitol Acetate ...______ ____________ 15 15 SO 2 NOPCO NXZ CMP Acetate 2 0.5 0.5 Ti Pure R-960 242.5 242.5 ASP 170 Clay 100 100 VICRON 25-11 112 112 35 CG 100 (46.5%) 70 70 Water.* 29 95 2 NOPCO NXZ 2 Ammonium Hydroxide____________________ 2 216 UCAR 370 (46%)................................ 61 40 Total 1265 1263 EXAMPLE IX Material: Pounds Pounds 45 315 4.3 3 5.7 4 60 15 15 2 0.5 242.5 65 Water 225.0 Bentone LT______________________________ 4.3 TAMOL 731--25% Active ............................. 3.0 VICTAWET 35B........ 12.7 ADVAWET 33.................................................... 9.0 Ethylene Glycol 15.0 Butyl Carbitol Acetate 15.0 NOPCO NXZ...................................................... 2.0 CMP Acetate............ .......................................- 0.5 Ti Pure R-960 242.5 ASP 170 100.0 VICRON 25-11.................................................. 112.2 100 Canadian Asbestos 6-D-20 (Canadian No. 112 6 shorts) __________________ _____________ 32.5 70 90 60 2 Water 326.0 NOPCO NXZ NAT-1 285.0 9.0 216 Total 1393.7 66 The properties and characteristics of the latex paints 1263 and dried films are listed in the following table. 343 unplt: Vlvostlr 0E.T7.).......... Reflectance................. - . PVC (percent)-....... .. Contrast ratio........... BoUdi (Percent)___ .... Yield (nitons).............. N.B. (rind No.............. table 1 11 III IV IVA V VI VIII vm 102-S 88-7 07-4 88 JOB 107 112 82 SI VI SI SI 18 10 vo VI VI 63.04 88. M SS.04 82.48 88.04 SS 04 83 04 58.04 O.V73 0.S78 0.V78 0.M1 Q.V67 0.WS7 o. v8y 0.V7S 62.48 82. SS 82. S 88. S 82.48 82 4 5 82.48 82.48 108 108 108 88 10B 108 108 108 7M a 8-8 8-8 8-8 8-8 8-8 8-8 IX 180 88 58.04 0*4 48.28 me 0 8.838,085 13 14 DISCUSSION (680%). Consequently, a portion of the asbestos fiber re mained uncoated giving a discolored film. Example 1 is a typical interior latex paint formulation The reflectance decreased to 88 as compared to 91 for (53.0% PVC, 54.9% Solids) which provides a standard Example 4. The contrast ratio was 0.983. Contrast ratio is measure of reflectance (91) and opacity (contrast ratio defined as reflectance over a black substrate divided by 0.967) for a 242.5 pound level of rutile titanium dioxide. the reflectance over a white substrate. The reflectance The pigments in this system require ISO pounds of water readings stated in this application are tested over a white to be properly dispersed leaving 226 pounds of free water. substrate. Therefore, paints with a lower reflectance will Since the asbestos has a water sorption of about 460%, be grayer and have a higher contrast ratio although the the quantity that can be added is a function of the dif- .. opacity may actually decrease as is the case in Exam ference in water demand between the asbestos and the pigment it is replacing as well as the free water available. ple 4A. The pigmented asbestos is compatible with diverse types The lowered amount of free water lowers the amount of of latex systems as well as oil and epoxy modified emul thickener required and this improves the flow and leveling sions as shown in Examples 5 to 8. In each case, stable rheology of the paint. Usually around 1-25%, preferably .. paints were prepared having acceptable application and 7-20%, of total pigments can be replaced with the high working properties. purity type chrysotile asbestos (HFTCA). Example 9 is an attempt to prepare a similar latex The water demand of the asbestos and therefore the paint utilizing Canadian Grade No. 6-D-20 shorts as level at which it could be incorporated into latex paints bestos. It failed in every possible desired criteria. The could be modified by treating the product with agents, .. Canadian asbestos could not be dispersed and gave a which induces bydrophobicity, such as fatty adds and z grind reading of 0 which is equivalent to a grind of no their derivatives, silicones, silanes and various other ma less than 4 mils, whereas the paints of the invention have terials. grinds between 0.5 and 2.0 mils, equivalent to a grind A dry titanated asbestos (35% TiOa) in pellet form was number of 4 to 7, and preferably less than 2 mils. predispersed and then incorporated into the formulation 25 The Canadian asbestos could not be liberated or pig of Example 2 at a 50 pound level, replacing 32.5 pounds mented since the film was very gray and the surface of calcium carbonate and 17.5 pounds of the original wrinkled indicating remaining available cationic charge. charge of TiOa which is now contained on the titanated The high viscosity is also indicative of available cationic fibers. The reflectance remains at 91 and the contrast charge. The water content was substantially increased and ratio was 0.973. 30 the solids dropped to 48.3%, yet the viscosity was still The asbestos has in effect predispersed the TiOa elec 150 K.U. A premium quality finish paint must have a trostatically along the fibers, thereby increasing its opacity viscosity between about 70 to 125 preferably 80 to 115 when incorporated into a coating. The high brightness is K.U. The random length Canadian No. 6-D-20 asbestos quite unexpected. Asbestos has a 72% G.E. brightness fibers are incapable of complete liberation and do not and with replacement of a portion of a high brightness pig- cofloc with anionic pigments to form totally pigmented ment this lower brightness material would be expected to products in which the cationic charge of the fibers is substantially lower the reflectance of the resulting paints. satisfied. The maintenance of high brightness is further indication The following are additional examples illustrating the that the asbestos fibers are electrostatically coated with invention. the high brightness anionic pigments which hide the gray- 40 ness of the fibers. There were several indications that the fibers were not completely liberated. The grind reading decreased from 7 to 4-5 indicating the presence of some fiber bundles. The film was slightly grayer indicating some of the fibers are not completely pigmented and the surface wrinkled Exampto Kxamjjje Example slightly indicating that cationic charge was available to coagulate the latex. Both of these latter effects could be due to compaction which prevents pigment deposition to ^ satisfy the cationic surface charge of the fibers. B parts TtO,, 1 put asbestos i-5 parts T10,,l pvt asbestos 10 pans TtOi. 1 put asbestos Example 3 is identical to Example 2, except titanated Ingredients: filter cake (51% solids) was substituted for the predis Water........................................ . CeUoslie QP-4400....................... persed pellet and the water adjusted for the filter cake Timol 731............ water component. The film had a reflectance of 91 and 65 VlcUwet S5-B.................. AdTtwel S3.............. a contrast ratio of 0.978. The grind reading improved to Nopeo NXZ................................ Ti pun R-980............................. 6 and no wrinkling was evident. Thus, the filter cake prod Asbestos CO 100 filter cake uct is in a more available form, can be dispersed with <447, eollds).............................. conventional equipment and provides a finer grind sur Butyl ear6ltol acetate............ . face. 60 U CAR-130.................................. Physical properties: In Example 4, the filter cake (untitanated 46.5% sol Viscosity (K.U.)_____ ......... Reflecunee..................... ids), and the titanium dioxide are added separately to PVC (percent)................. the pigment dispersion. The reflectance is again 91 and Contrast raUo.......................... Total solids (percent).......... ...... the contrast ratio is 0.976. This demonstrates that the Yield (calIons).............. . asbestos fibers are in fact coflocculating with the anionic 96 N.B. (nod No______________ _ eso as fiO 11.4 10 4.0 5710 145 5 sao so.o 4015 IS U 45.04 asTss 45.00 151 650 as 10 11.4 10 4.0 574.0 154.0 sao 10.0 46X1 Ti 92.6 41.15 a TOO 4104 102 0 au as ao 11.4 ao 4.0 6710 131.0 sao 300 4007 74 03 4274 a 9755 49.20 190 0 pigments during paint manufacture. The fibers are coflocculating with more than the titani um dioxide and the extender pigments are filling in the available spaces on the fibers. The pigment demand of the jq totally liberated fibers is about 900 to 1000% by weight. In Example 4A, the amount of filter cake was increased to 50 pounds. The resultant paint gave a grayish appear ance when compared to the paint of Example 4. Only 342 pounds of the preferred anionic pigments are available 76 Referring to Examples X, XI and XII the viscosity of 65-78 for all of these compositions is within the usable range. As to reflectance, however, it is noted that Ex amples X and^CIs-wkh ratios of pigment to asbestos of A i o DO/ 8.838,085 15 16 9 to 1 and 10 to 1 respectively have the ume high re* consisting essentially of about 4 to about 25% anionic pig flectnnce values of 93, whereas Example XI, with a ratio ment. and said paint composition having a grind less than of 8.5 pigment to 1 part asbestos, and below the 9 to 1 lower limit of the invention paint composition, has a 2 mils. 3. The paint composition according to claim 2 in which lower reflectance of 92.5, and hence a lower brightness . the polymer is selected from polymers of n! least one as compared to the paints of Examples X and XII. monomer selected from the group consisting of vinyl ace Also, it is noted that Examples X and XII have a con tate, ethyl acrylate, isohutyl acrylate, methyl methacrylate, trast ratio of 0.9785 whereas Example XI, having a pig N-butyl acrylate, methacrylic acid. N*meihylol acryl ment to asbestos ratio of 8.5 to 1, has a reduced con amide, acrylonitrile, 2-ethylhexyl acrylate, acrylic acid, trast ratio of 0.9730, indicating that opacity and hiding J0 itaconic acid, styrene, butadiene, ethylene, and vinyl power at a pigment to asbestos ratio of 9 to 1 or greater, chloride. are at a maximum for a given quantity of biding pigment 4. The paint composition according to claim 2 in which to asbestos, and such contrast ratio remains at such maxi the polymer is polyvinyl acetate. mum with increase in the ratio of pigment to asbestos 5. The paint composition according to claim 2 in which above 9 to 1, whereas such opacity and hiding power un- ^ the polymer is a copolymer of vinyl acetate and an acrylic desirably decreases at a ratio of pigment to asbestos be ester. low 9 to 1. 6. The paint composition according to claim 2 in which In summary, the particular high purity chrysotile as said pigment includes a mixture of anionic hiding pig bestos in accordance with the invention can be com ment and anionic extender pigment. pletely liberated and can in this form completely cofloc go 7. The paint composition according to claim 2 in which with at least 9 times its weight of anionic pigment, usually the polymer is polyvinyl acetate, and said pigment in 900% to 1000% by weight of anionic pigments. The pig cludes a mixture of titanium dioxide, kaolin clay and ments are dispersed along the length of the asbestos fibers calcium carbonate. and hide the relative grayness of the fibers, increasing 9. The paint composition according to claim 2 in which opacity. The opacity difference is quite dramatically dis- 25 the polymer is a copolymer of vinyl acetate and butyl played with 1.5 mil films are observed on a hide chart. acrylate, and said pigment includes a mixture of titanium The physical nature of the colloidal fibers with an aver dioxide, kaolin day and calcium carbonate. age L/D ratio of 200 provides reinforcement by the 9. The paint composition according to claim 2 in which whisker effect and improves the structural integrity of the the polymer is a copolymer of ethyl acrylate, methyl meth paint film. The film has a high tensile strength and can 30 acrylate and methacrylic acid, and said pigment includes a experience large changes in substrate dimensions before mixture of titanium dioxide, kaolin clay and calcium car the film cracks or fails. The durability, scrubbability and bonate. service life of the film are considerably enhanced. 10. The paint composition as defined in claim 3. includ Another desirable result is the degree of pigment dis ing a thickener, a surfactant and a coalescing agent. persion attainable when the asbestos in filter cake form 35 11. A method of forming am aqueous emulsion latex is incorporated into latex paints. The prior available dry paint composition containing, by weight, about 20 to 70% Canadian fibers were limited to a maximum dispersion or aqueous diluent, about 5% to 50% by weight of anionic grind of 3.5 mils while the filter cake yields a dispersion latex resin solids comprising a polymer of an ethylenically or grind of 1.2 mils. This is the first material which allows unsaturated monomer containing a polymerizable vinyl the use of asbestos in premium interior and exterior paints. *0 group, and pigment, the steps comprising: It is to be understood that only preferred illustrative em bodiments of the invention have been disclosed and that numerous substitutions, alterations and modifications can readily be -practiced by those skilled in the art without dispersing in water, high purity, liberated, cationic chrysotile asbestos fibrils having an ultimate fiber yield of at least 85%, a surface area of about 60 to 80 meters*/gram, a reflectance of at least 72% and a magnetite content below 0.8% to form a colloidal departing from the spirit and scope of the invention as de- suspension; fined in the following claims. adding anionic pigment to the suspension in an amount We claim: of at least nine times the weight of the asbestos to / 1. An aqueous latex emulsion paint composition having / a fine grind and capable of forming a film of high bright- electrostatically cofloc and bond said pigments along the length of said asbestos fibrils and to completely ness and good opacity, consisting essentially of, by weight satisfy all of the cationic charge on said fibrils; of said composition, forming a pigment dispersion containing said pigmented about 20 to 70% aqueous diluent; asbestos fibrils; and then about 5% to 50% of latex resin solids consisting essen adding said anionic latex resin to the pigment disper tially of a polymer of an ethylenically unsaturated flj sion and blending to form an intimate dispersion hav monomer containing a polymerizable vinyl group; ing a grind less than 2 mils. about 4 to about 65% of pigment, said pigment includ 12. The method according to claim 11 in which the ing anionic pigment; and polymer is selected from the group consisting of polymers \ a colloidal suspension of pigmented asbestos consisting essentially of an effective amount of short, high purity, liberated, cationic chrysotile asbestos fibrils having an 60 of at least one monomer selected from the group consist ing of vinyl acetate, ethyl acrylate, isobutyl acrylate, methyl methacrylate, N-butyl acrylate, methacrylic acid, N-methylol acrylamide, acrylonitrile, 2-thylhexyl acry ultimate fiber yield of at least 85%, a surface area of late, acrylic acid, itaconic acid, styrene, butadiene, ethylene about 60 to 80 meters'/gram, a reflectance of at least and vinyl chloride. 72% and a magnetite content below 0.8%, said fibrils 13. The method according to claim 11 in which the being pigmented with anionic pigments which are polymer is selected from the group consisting of polyvinyl electrostatically bonded at discrete points along the acetate, a copolymer of vinyl acetate and butyl acrylate, length of the fibrils in a ratio of at least nine times and a copolymer of ethyl acrylate, methyl methacrylate anionic pigment to asbestos, by weight, so as to com and methacrylic acid. pletely satisfy the cationic charge on said asbestos 70 14. The method according to claim 12, wherein said fibrils. pigment includes a mixture of anionic hiding pigment and 2. The paint composition according to claim 1, said anionic extender pigment. paint composition containing about 5% to 25% of said 15. The method according to claim 13, wherein said latex resin solids, and having a pigment volume concen pigment includes a mixture of titanium dioxide, kaolin tration of between about 15% and 80%, said pigment 75 clav apd calcium carbonate. ^ 1 ^058 8,838,085 17 16. The paint composition according to claim 1, laid 2,833.737 pigmented asbestos ranging from 1% to 25% of total 2,914,495 pigment solids. 3,578,618 18 5/1958 Mark et al---------------- 260--29.6 R 11/1959 Cordon el al260--29.6 R 5/1971 Beardsley ____ .... 260--29.6 R References Cilad UNITED STATES PATENTS ^ HAROLD D. ANDERSON, Primary timiiw 3.033.806 5/1962 Murray et aL_____ 260--29.6 R 3.214.398 10/1965 Vannoy----------------- 260--29.6 R 3,328,238 6/1967 Knowles et al167--16 U.S. CL X.R. 106--288 B; 260--17 R. 17.4 R. 23 R. 23.7 A. 27 R. 29.7 R, 29.6 RW, 29.6 H, 29.6 ME, 29.6 TA; 423--331 \ A ? "1 r\ r- -v A ^OOd SqpL 24, 1974 j. l. myers ptal 3,838,085 FIOMENTED ASBESTOS LATEX EVULSION FAINT COMPOSITION Filed Sep4.. 24. 1972 (4 2 Sbeete-Sbeet 1 INVESTORS JOHN L MYERS RICHARD W LASHER By RUSSELL D JAMES ATTORNEYS I, 1974 J. L. MYERS ET AL 3,858,085 PIGMENTE'.' ASBESTOS LATEX EVULSION PAINT COMPOSITION Filed Sept. 24. 1972 2 Sheete-Sheet a A'OGGI RICHARD W. LASHER BY RUSSELL D. JAMES ' ATTORNEYS.