Document g6wdeLDrg13V7EbgLkkQY3ZL

FILE NAME: Westinghouse (WH) DATE: 1962 Jan 23 DOC#: WH098 DOCUMENT DESCRIPTION: Patent - Fire-Resistant Decorated Composite Laminate Members and Method of Producing the Same PLAINTIFF'S EXHIBIT < Q tc w u J ^ Jan. 23, 1962 w . c. h o o d e t a i 3,018,206 FIRS-RESISTA!.'" DECORATED COMPOSITE LAMINATE MEMBERS ' ANO METHOD OF PRODUCING SAME Filed Oec. 31. 1957 C Overlay Sheet Im pregnated with n /' ( / r 'y 7' A ^ WITNESSES INVENTORS W illiam C Hood 8 ^ v i d E Baldwin ATTORNEY I_ f PLAINTIFF'S . EXHIBIT U)H-7</o United States Patent Office Patented Jan3.,0231,8,1290662 1 2 j.m iunr. prcpnnted protective overlay sheet is employed O'er f i r e -r f .s is t a n t d f c o k a i f .d c o m p o s it e i .a m - sheets having designs imprinted thereon to provide better JNATE MEMUFIJS A M ) M ETHOD OF IMtODDC- abrasion resistance and good surface appearance theic- INC SAMF. to. Pigmented sheets that have no design imprinted William C. Ilnnd. Vnrnvillr. ami I1;i*i<! E. Baldwin, o thereon will ordinarily have good abrasion resistance Hampton. S.C., atvi|>tion In \Vn'iii;liirac Klcdric and hence an overlay sheet is not required. Suitable ma Corporation. East PidUmi gli. Fa., a corporation of terials for overlay sheets include rayon, glass fabric and Pennsylvania ,, Filed Occ. 31. 1957, 5r. No. 706.31* alpha-ccllulosc paper. In accordance with this invention, when an overlay sheet is employed, it will be impreg 5 Claims. (Cl. 154-- 45.9) 10 nated with a clear melamine-aldehyde resin. This invention relates to composite laminate members Any commercially available asbestos paper sheeting and particularly to composite decorated laminate mem uch. for example, as that available under the proprietary bers having good fire-rcsistancc ar.i to the method of name Novahestos, may be employed in preparing the producing same. laminates of this invention. Decorated laminate members have enjoyed wide If. Sheets of asbestos paper are impregnated with any spread use in the building industry, especially as deco well known conventional thermosetting phenolic resin rative wall panels, ceiling panels and the like. Many prepared hy reacting phenol, cresol. or crcsylic acid with applications require that the decorative panels be fire- formaldehyde, paraformaldehyde or other polymers of resistant. This is particularly true when the decorative formaldehyde, ordinarily in the presence of an alkaline panels are used as bulkhead construction in ships, and 20 catalyst such as ammonia, sodium hydroxide. lime, or wall construction in hospitals. olTicc buildings and the barium hydroxide. A volatile solvent such as ethyl al like. Heretofore, attempts have been made to produce cohol. toluene or xylene is added to the resin to produce fire-resistant decorated laminate members, however, the an impregnating varnish. The resin solids content of laminates have not possessed adequate physical strength the varnish may be varied from about 20% to 60% by and other desirable physical properties. Attempts to zr, weight. improve physical properties have resulted in a consid A suitable resin may be prepared by reacting 1 mol erable reduction in firc-rcsistancc to a point where the of phenol and from 0.9 to 1.7 mots of formaldehyde in material could not be classified as fire-resistant. It is a closed reaction vessel under reflux conditions for at highly desirable to have available in the art decorated least 1 hour, the reaction being catalyzed by an alkaline laminate members that have good fire-resistance and high 30 catalyst such as ammonia and then vacuum dehydrated physical strength. at a temperature not exceeding 100* C. The object of this invention is to provide composite Example I decorated laminates comprising sheet fibrous material The following is an example of the preparation of a impregnated and bonded together by thermoset resinous compositions, which laminates have good fire-resistance 33 partially reacted thermosettable phenolic resin that may be employed in carrying out this invention: and high physical strength. Into a steam heated reaction kettle there are intro Another object of this invention is to provide a method for producing decorated laminates of high physical duced the following: Parts by weight streOntghtehr aonbdjegcotsodoffitrhci-srcisnivsteannteioe.n will, in part, be obvious 40 PFhoermnoalld_e_h_y_d_e_ .(.3.7.%. .) . ___________________. _. ._._._._._._._._________110104 and will, in part, appear hereinafter. Ammonia (28% ) ___________________________ 3.73 For a better understanding of the nature and objects of the invention, reference should be had to the follow These materials are reacted in the steam heated reaction vessel at a temperature of approximately 100* C. under ing detailed description and drawing in which the single 45 reflux conditions for a period of about lVi hours. The FIGURE is a schematic view of an assembly of sheets in mixture is then dehydrated under a vacuum of 28 inches accordance with this invention. of mercury, and the temperature gradually increxsed to In accordance with this invention a decorated com approximately 75* G during dehydration. Substantially posite laminate member is prepared which has good fire- ail the water is removed. To the hot reaction product resistance and high physical strength. The composite 60 there is added 81.5 parts by weight of 95% ethyl alco Laminate member comprises a core or body layer com hol and the resulting resin varnish is then permitted prising a plurality of sheets of asbestos paper impreg to cool to room temperature. This resin vamish has a nated with a phenolic condensation product and a deco viscosity of from 180 to 400 ccntipoiscs at 25* G and a rated surface layer impregnated with a clear mclaminc- set time of from 13 to 16.5 minutes at 153.5* G aldebyde resin. 6S Another particularly good resin composition that may The decorated laminate members of this invention he employed in impregnating the sheets of asbestos paper will usually be adhesively bonded to a rigid backing sheet is a dicynndiamide-phenol-formaldehyde resin composi of fire-resistant material having a thickness of from about tion. Such a resinous composition is derived by reacting Vi inch to 1 inch to provide suitable fire-resistant panels. phenol, dicyandiamide and formaldehyde in the propor The panels thus produced arc well suited for structural 00 tions of I mol of the phenol, from 0.8 to 2 mols of di materials for the marine industry, hospitals and the like cyandiamide and from 0.9 lo 1.5 mols of formaldehyde where fireproof structures arc required. An example of per mol of the combined phenol and dicyandiamide. a suitable rigid backing material N that available com Water is present, being.usually furnished as a part of mercially under the proprietary name Marinite. TTie aqueous formaldehyde solution (37% to 40% ), and adhesive eomposiiion employed is preferably a fire-re 0.1 amounting to at least 10% of the weight of the reactants, sistant type such as the silicon type adhesives. and ordinarily should not exceed the weight of the re The decorated surface layer may comprise a sheet of actants. The mixture is reacted under alkaline conditions alpha-ccllulosc raper, thin cotton fabric, silk, glass fab for at least Vi hour, and preferably by refluxing from 1 ric. asbestos paper or like fibrous sheet material with a to 2 hours, and then is vacuum dehydrated at a tempera design imprinted thereon or the slicct may be pigmented 70 ture not exceeding 100* C. until substantially all of the throughout. Pigmenied sheets with designs imprinted water is removed and then a volatile solvent is applied to thereon may also be employed. Ordinarily, a resin im- produce an impregnating varnish. 3,018,200 3 The resin varnish employed to impregnate the Asbestos paper sheets may include a small proportion, of the order of 2% to 10% by weight, of finely divided inorganic solids sueh-as silica, aluminum oxide, antimony oxide and the like refractory solids to impart better flame resistance to the final product. The following example is illustrative of the method of preparation of a suitable dicyandiamidc-phcnol-formaldehyde resin for use in this invention. Example 1 into a steam heated reaction kettle there are introduced the following: Parts by weight P h e n o l__________ ______________________. . . 2750 Dicyxndinmide__________________ . . . _________ 2100 Formaldehyde ( 3 7 % ) ______________________ _ 4620 Ammonia (28% ) _________________________ __166 The ammonia and the formaldehyde are admixed before being introduced into the kettle with the remainder of the ingredients, the mixture having a pH of approximate ly 8.5. The mixture is slowly heated, and at SO* C. an exothermic reaction takes place that carries the tempera ture to approximately 95* C. Additional heat is then surphed in order to cause the reaction mixture to reflux. The mixture is refluxed for 90 minutes and then dehy drated under a vacuum of 27 inches of mercury, and the temperature gradually increased to approximately 75* C. during dehydration. Substantially all the water is re moved. To the hot reaction product there are added 2000 parts by weight of 95% ethanol, and the resulting thick varnish is cooled to room temperature. The resin ous reaction product is then further diluted with a mix ture comprising 50% by weight of ethanol and 50% by weight of water to produce an impregnating varnish com prising approximately 53% by weight of resin solids. The viscosity of the composition is approximately 250 ecntipoiscs at 25* C. a Particularly good results have been obtained by im pregnating sheets of asbestos paper with a mixture of from 2 parts to 4 parts by weight o f a conventional phenolic resin and 1 part by weight of a dicyandiamide- phenol-formaldehyde resin dissolved in a suitable solvent such as ethyl alcohol to provide a varnish composition having from 20% to 60% resin solids. Tbe following example is illustrative of a suitable mix ture to be employed in carrying out this invention. Example 1! Three parts by weight of the resinous reaction product of Example I and one part by weight of the resinous reaction product of Example 11 and 15 parts by weight of 95% ethyl alcohol are thoroughly admixed by agita tion to form an impregnating resinous varnish composi tion. This resin varnish has a viscosity of from 60 to 150 centipotses at 25* C. and a set time of from 13.5 to 17.5 minute* at J53.5* C. Tbe sheets of asbestos paper may be impregnated with the resin varnish composition of this invention in any con ventional manner, for example, as described in the patent to Wellman et al,, Patent No. 2,579,637. It is important, for the purposes o f this invention to employ a resin ratio of the impregnant within the relatively narrow range of from 1.35 to 1.80. Resin ratio is defined as tbe ratio o f the weight of the untreated fabric plus the weight of tbe resin that is impregnated in the sheet to the weight of the untreated fabric. In other words, the treated fibrous ma terial carries resin in an amount equal to from 35% to 80% of the fibrous material alone. T o achieve the ulti mate in fire-resistance the very minimum amount of resin is desired; however, to obtain desired physical properties, such as good moisture resistance, good dimensional sta bility, good impact strength and the like, a somewhat greater amount of resin content is desired. Thus, asbestos paper sheeting is dipped in tbe varnish ... 4 one or more times until it has picked up resin solids in an amount of from 0.35 to 0.80 limes the weight of tbe dry asbestos _pnper and the varnish impregnated asbestos p.iper is passed through an oven or other dryer after each S dip to remove the volatile solvent. During drying, it is desirable to bent the asbestos paper treated with the varnish composition at a temperature of from 110* C. to 160* C. in order to remove the solvent therefrom prompt ly and to advance the cure of the resin well into the "B" 10 stage. The heat treatment of the applied resin at this stage is conducted so that the resulting treated fabric bis a "greenness" o f from 0.3% to 6%. The greenness is determined by placing a stack of small pieces of the resin treated sheet material in a hot press and pressing it at a 15 temperature of 175* C. and a pressure of 1000 pounds per square inch for 5 minutes, and then measuring tbe amount of resin that is forced out of the stack, that is, the resin that extends beyond the fibrous sheet material proper, and determining the proportion of ibis exuded 20 resin to the total weight of the sample. It is also essential that the greenness be controlled and kept within the above limits. It s important to have ade quate greenness so that a homogeneous laminate is ob tained. However, if the greenness is too high, a burst25 iug of the asbestos fibers is encountered during laminat ing process and the resin tends to flow into the decorated layer causing a discoloration of same. Details of the laminating procedure will be set forth hereinafter. The decorated sheet material and protective overlay, if 30 one is employed, are impregnated with at least 50% of their weight with a clear thermosetting melamine-aldehyde resin. It will be appreciated that in many case*, tbe melamine-formaldehyde resin have been made in the pret ence of butanol and that they comprise butyiated poly- . 33 (tiers. The terms "melamine-aldehyde" are intended to apply to such compositions which comprise essentially these reactants as the main ingredients but may contain other ingredients such as sulfonamides, glycols, glucosides and the like which are added to provide special properties 40 such as flexibility, craze-resistance and tbe like. The manufacture of the melamine-aldehyde resins suitable for the practice of the present invention is well known in theart and need not be detailed herein. Referring to the single figure of the drawing, there is 45 shown a stack 10 which comprises sheets 12 of absestos paper impregnated with B-stage phenolic resin, decorated sheet 14 and protective overlay sheet 16 both of which are impregnated with B-stage melamine-aldehyde rests. The stock 10, as shown in tbe figure of the drawing is 50 introduced into a molding press where the stack is sub jected for a specified period of time to a temperature of from about 260* F. to 320* F., white under pressure. Pressures of from 500 p.s.i. to 1500 p.s.i. are satisfactory, while pressures of from 1000 p.s.i. to 1200 p.s.i. give best 55 results. The curing cycle must be closely controlled so that adequate and complete cure of the melamine-aldehyde resin and the phenolic resin will be effected. Adequate curing of the resin components is obtained la about 25 minutes to 25 minutes at a temperature of from about 00 260* F. to 300* F. The following examples illustrate the preparation of composite decorated laminate members in accordance with this invention. Example IV Eight sheets of asbestos paper (12 inches x 12 inebes x 0.010 inch) arc impregnated with the phenolic resin var nish of Example I, to a resin ratio of about 1.60 and a greenness of about 1.0% and the solvent removed. One sheet (12 inches x 12 inches x 0.010 inch) of pigmented alpha-cellulose paper is impregnated with melamine-alde hyde resin varnish to provide a resin ratio of about 2.20 and the solvent removed. A stack was prepared by super imposing one sheet of impregnated ashcuos paper on tho 75 other and the impregnated pigmented sheet placed on tbo 3,018,208 5 6 top o f the stacked asbestos sheets. The stack is consoli ing. (2) superimposing a plurality of layers of the resin dated or molded into a composite laminated member at a treated asbestos paper sheeting to provide a stack. (3) ^ pressure of 1000 p.x.i. and at a temperature of about 280* superimposing a decorated sheet of fibrous material im F. for a period of about 19 minutes. The resulting lami pregnated with a potentially thermoscttable clear mela nate has good surface characteristics, good physical proper- 0 mine-aldehyde resin on top of the slack to provide a com ties and good fiic-rcsistance. posite member, and (4) molding the composite member Crumple V at a pressure of from 300 to 1500 pounds per square inch at temperature of from 135* C. to 165* C. Ten sheets of asbestos paper (12 inches * 12 inches x 2. The process of claim I wherein a protective over 0.010 inch) arc impregnated with the phenolic resin var- io lay sheet of fibrous material impregnated with a poten nixh of Example II. to a resin ratio of about 1.60 and a tially ihcrmoxcitahlc clear melamine-aldehyde resin is greenness of about 1.0% and the solvent removed. One superimposed on top of the impregnated decorated sheet sheet (12 inches x 12 inches x 0 .0|0 inch) of pigmented prior to molding. . alpha-cellulose paper is impiegnatcd with melamine-alde 3. A fire-resistant decorated composite laminate mem hyde resin varnish to provide a resin ratio of about 2.00 16 her comprising (A) a surface layer comprising a decorate- and the solvent removed. In accordance 1*1111 the method slicet of fibrous material impregnated with a thermost of Example IV a composite decorated laminate member mclaminc-aldchyde resin and (B) a body layer comprisin is prepared. This laminate has good surface quality, ex a plurality of sheets of asbestos paper impregnated with cellent fire-resistance, and high physical strength. a'ilicrmosct resin 'composition comprising from 33% to Example V t 20 s8e0t%resoifnthceomwpeoigshittioonf tchoenassibsteinstgosopfa(pIe)r aflroonme.'2thpeatrhtser(mo o4 Six sheets of asbestos paper (12 inches x 12 inches x parts by weight of a phenolic resin derived by reacting 1.0 0.010 inch) were impregnated with the phenolic resin mol of a phenol and from 0.9 mol lo 1.7 mols of form varnish of Example 111. to a resin ratio of about 1.60 on aldehyde under reflux conditions for at least 1 hour, the a greenness of 1% and the solvent removed. One sheet 23 reaction being catalyzed with an alkaline catalyst, and (hen (12 inches x 12 inches x 0.010 inch) of pigmented alpha vacuum dehydrated at a temperature not exceeding 100* cellulose paper having a design imprinted thereon and C. and (2) one part by weight of the resinous reaction one sheet (12 inehes x 12 inches x O.IWt) inch) of rayon product derived by reacting one mol of a phenol, from fabric are impregnated with mclaminc-aldchyde resin 0.8 to 2.0 mols of dicyandiamide. and from 0.9 mol to varnish and the solvent removed. The sheet of alpha- 30 1.3 mols of formaldehyde per mol of the combined phenol cellulose paper is provided with a resin ratio of about 1.70 and dicyandiamide in the presence of water, the mixture and the rayon sheet with a resin ratio of about 3.00. A being refluxed for at least Vi hour, and then vacuum de stack is assembled by superimposing one sheet of impreg hydrated at a temperature not exceeding 100* G . the-said nated asbestos paper on the other. The sheet of pig decorated sheet and asbestos sheets being consolidated mented alpha-cellulose paper is placed on top of the stack 33 and bonded together into a unitary member. and the rayon sheet is placed on top of the pigmented 4. A thermosettable resinous composition consisting of sheet. In accordance with the method of Example TV a ( I ) from 2 parts to 4 parts by weight of a phenolic resin composite deeomlcd laminate member is prepared. This derived by reacting 1.0 mol of a phenol and from 0.9 mol decorated laminate member is adhesively bonded to a one inch thick sheet of Marinite bv usine a heat resistant <0 adhesive composition to produce a compmnc member. This composite member was tested using tiie Underwriters' Laboratories, Inc., test entitled "funnel test lor hire Re sistance of Building Materials." I he loliowinc results'1* were obtained: 43 Rate of flame sp re a d __________________ ________- 13 fruel contributed - _! . . ________- ________ ________ 13 .Smoke developed___________________ ___________ 0 lo 1.7 mols of formaldehyde under reflux conditions for at least one hour, the reaction being catalyzed with an al kaline catalyst, and then vacuum dehydrated at a tempera ture not exceeding 100* G . and (2) one part by weight of the resinous reaction product derived by reacting one mol of a phenol, from 0.8 mol to 2.0 mols of dicyandiamide, and from 0.9 mol lo 1.3 mols of formaldehyde per mol of the combined phenol and dicyandiamide in the presence of water, the mixture being refluxed for at least Vi hour, and then vacuum dehydrated at a temperature not exceed, ing 100* G It will be understood that the above examples and de- SO 3. A resinous impregnating varnish composition con senption and drawing are illustrative and not in limitation sisting of (1) from 2 parts to 4 parts by weight of a of the invention. phenolic resin derived by reacting one mol of a phenol We claim as our invention: and from 0.9 mol lo 1.7 mols of formaldehyde under re 1. In the process of preparing a fire-resistant decorated composite laminate member, the steps comprising (1) 65 impregnating asbestos_2.aper sheeting with a solution of a thermoseitaBIe.!xesioous composition consisting of (A) from 2 parts to 4 parts by weight of a phenolic resin de rived by reacting 1.0 mol of a phenol and from 0.9 mol to 1.7 mols of formaldehyde under reflux conditions for 00 at least one hour, the reaction being catalyzed with an al kaline catalyst, and then vacuum dehydrated at a tempera, ture not exceeding 100* C. and (B) one part by weight of flux conditions for at least 1 hour, the reaction being catalyzed with an alkaline catalyst and then vacuum de hydrated at a temperature not exceeding 100* G (2) one part by weight of a resinous reaction product derived by reacting I mol of a phenol, from 0.8 to 2.0 mols of di cyandiamide. and from 0.9 mol to 1.5 mols of formalde hyde per mol of the combined phenol and dicyandiamide in the presence of water, the mixture being refluxed for at least Vi hour, and then vacuum dehydrated at a tem perature not exceeding.100* G , and (3) a solvent therefor. the resinous reaction product derived by reacting one mol of a phenol, from 0.8 mol to 2.0 mols of dicyandiamide, OS References Cited in the file of this pateot and from 0.9 mol to 1.5 mols of formaldehyde per mol of UNITED STATES PATENTS the combined pbenot and dicyandiamide in the presence of water, the mixture being refluxed for at least Vi hour, and then vacuum dehydrated at a temperature not exceed ing 100* C.. the resin impregnated sheet fibrous material 70 being heated to drive olT the solvent and to advance the cure of the resin to a condition where its greenness i* from 0.3% to 6% . the asbestos paper sheeting carrying from 0.33 to 0.80 times its weight of the resin after dry- 2.439.929 2.604.427 2.732.323 2.740.737 2.801.198 2.802.672 2.824,849 Hill et 1 !................................Apr. 20. 194g Armstrong et a l . -------------- July 22. 1952 Lindenfelscr et al. . . . . . . . . Jan. 24. 1956 Elmer et al............................Apr. 3. 1956 Morris et al........................... July 30. 1957 Baldwin et al..........................Aug. 6. 1957 Boiney...................................Feb. 25. 1958