Document 71oqQkarnN9b7eNjNYQ6vnR4V

Bl I United States Patent Williams USG 0 mi 3,891,453 June 24, 1975 1541 asbestos-free joint compounds 175] Inventor: Terrance L. Williams, Crystal Lake. III. [731 Assignee: United States Gypsum Company, Chicago. 111. [221 Filed: July 26, 1973 [21[ Appl. No.: 382,973 1.785.053 2.662.02-1 3.279.934 3.297,601 12/1930 12/1953 10/1966 1/1967 Stoddcr.................................. 106/1 U Riddell ct al........................... 106/109 Schuppncr............................... 106/85 Maynard ct al............................. 260/8 Primary Examiner--Delbert E. Gantz Assistant Examiner--James W. Hellwcge Attorney, Agent, or Firm--Samuel Kurlandsky. Esq.; Stanton T. Hadley, Esq.; Kenneth E. Roberts. Esq. [52] [511 [58] U.S. CL................... 106/85; 106/109; 106/111; 106/115 Int. CL............................................... C04b 11/16 Field of Search............. 106/85. 109. 110. 1 U. 106/114, 115 [ 5 61 1,587.973 References Cited UNITED STATES PATENTS 6/1926 MakowsJd 106/115 [57] ABSTRACT A joint compound' which is preferably asbestos-free, for use in finishing joints between wallboards. com prising a filler, a binder, and any two or all three of a water-holding agent; a slip-inducing colloid; and a non-swelling clay having sufficient pseudoplasticity to render the composition non-leveling. 12.Claims, 3 Drawing Figures PLAINTIFF'S EXHIBIT HG--374 o a o o c> PATENTED JO*24 ms SHEET 1 3.891.453 / 2 `JtO H O d O Viscosity ( Poises) C y tG 11 OcjO PATENTED JUH24 1975 SHEET 2 3,891,453 3,891,453 12 ASBESTOS-FREE JOINT COMPOUNDS Thus, an asbestos-fres joint compound is needed BACKGROUND OF THE INVENTION Heretofore, such has not been readily obtainable, due to the unique combination of features provided bv as In the construction of buildings, one of the most com bestos. especially concerning the workability of tpe mon elements is gypsum wullboard. often known us 5 joint compound. 'drywall," used to construct the walls and/or ceilings. Walls made from gypsum wullboard arc conventionally SUMMARY OF THE INVENTION constructed by fixing the panels to studs, and filling and The invention concerns the discovery that asbestos coating the joints with a specially prepared adhesive has provided certain functions in joint compounds called a joint compound. This process generally pro 10 which can be obtained from certain asbestos substi ceeds in the following fashion: a taping grade joint tutes. More specifically, it has been found that an ac compound is placed within the joint formed by the ceptable joint compound can be obtained, for use in abutted edges of the wallboards. and a perforated tape finishing joints when mixed with water, from a mixture is embedded within the taping compound. When dry comprising1 a filler selected from the group consisting (or set), a second, topping grade joint compound is 15 of calcium carbonate and calcium sulfate: a binder: and coated over the joint. This may be sanded lightly, and two of the following three ingredients: a watcr-holdine a third coat is applied and conventionally finished. An agent, a slip-inducing colloid, and a non-swelling clay other grade of joint compound is an all-purpose grade having sufficient pseudoplasticity to render the compo which may be used, as the name suggests, for embed sition non-leveling. In most instances, all three of the ding the tape and for the finishing coats. In some in 20 above are used for best results. stances. a patterned effect is given to the all-purpose Accordingly, it is an object of the invention to pro joint compound to leave a textured finish. The primary difference in the past between the vari vide a joint compound having working properties here tofore achieved only thrcnich the use of asbestos, with ous grades of joint compound has been in the differ out the necessity of including asbestos in the formula ences in the amounts of each ingredient. Thus, no mat 25 tion. ter what the grade, joint compounds invariably include It is a related object of the invention to provide such a filler and a binder. More binder is used for the taping a joint compound either in dry powder form or ready- grade than for the topping grade. Typical fillers may be mixed form, and either as a setting type or a drying calcium carbonate, calcium- sulfate hemihydrate, or type. ; calcium sulfate dihydrate. As is obvious, the choice de 30 Other objects and advantages will become apparent termines whether the joint compound hardens by dry upon reference to the following brief description of the ing or by setting. An example of a setting type joint drawings and the description of the preferred embodi compound is taught in U.S. Pat. No. 3,297,601. ments. | In addition, conventionally it has been necessary to include asbestos as a key ingredient. However, asbestos 35 BRIEF DESCRIPTION OF THE DRAWINGS is becoming more and more an unacceptable health ha FIG. 1 is a log-log graph of shear rate versus both ap zard, particularly where airborne. Health experts have parent and differential viscosity, measured for One of indicated that not oniv does it cause mesothelioma, it the ingredients utilized by the invention: may cause other forms of lung cancer as well, and may FIG. 2 is a graph illustrating shear rate versus appar be a greater source for the latter than automobile 40 ent viscosity for another ingredient and. fumes. Because of such effects, the Occupational FIG. 3 is a semi-log graph of viscosity versus RPM for Safety and Health Administration has established a yet another ingredient used in the invention. U.S. Asbestos Standard, published in vol. 37. pp. 1 1320-11322 of the Federal Register, which provides that, at no time may the concentration of the asbestos 45 DESCRIPTION OF THE PREFERRED EMBODIMENTS fibers longer than 5 micrometers exceed 10 in number It has been found that asbestos in joint compound per cc. of air. In addition, effective July 1. 1976. the provides three functions: non-leveling, slip, and water airborne concentration of asbestos longer than 5 mi retention. The first two of these control the workability crometers in any working area, on the average, may not exceed two fibers per cc. of air. The asbestos in joint 50 of the joint compound. By "non-leveling." it is meant the ability of the joint compound to retain at least tem compounds becomes airborne in two ways: when the porarily a given shape against the intluencc of gravity. compound is dumped into water, and when the dried or Other examples of this property include soft butter or set coat is sanded prior to the application of another a cake frosting. By "slip." it is meant the ability to coat or some other finish. Hand mixing the dry mix of ingredients into water is a primary first step, as many 55 spread smoothly in a frictionless manner, without drag. It further has been found that two or all of three in joint compounds are packaged dry and wetted by the gredients will provide the foregoing three functions, de applicator on site. The microscopic fineness of the as pending oh the grade and type of joint compound de bestos causes it to literally puff into the air into an invis sired. The best results are obtained when the ingredi ible cloud. Actual measurements have indicated that such mixing may cause a concentration of asbestos fi 60 ents are "selected fro'm 1) sodium carboxymethylccilulose. hereinafter SCMC. 2) attapuigus clay, and 3) bers longer than 5 micrometers of up to 55 fibers per a slip-inducing colloid such as amine-modified mont- cubic centimeter of air in the breathing area in the vi morillonite clay gel or xanthan gum. All three of these cinity of the mixing period. Sanding may cause a fiber act as water-retention aids or water-holding agents, the concentration of slightly over 3 fibers per cc. of air over an extended period of time. Clearly, by 1976. the con 65 SCMC having this as its primary function. The nonIcvcling function is provided primarily by the attapui ventional formula and the use of asbestos therein will gus clay. The slip is provided by both the attapuigus hardly meet the above Asbestos Standard. clay and the colloid. The relative amounts depend upon , 3,891,453 34 the grade of compound desired, bui in general ihc SCMC may be between about U. I and about I percent, -Continued the attapulgus day between about (L"5 and about 6 per cent. and the colloid between about l). I and about 2 percent, all measured as a percent of the total dry- 5 weight. Other water-retention aids, particularly those con taining cellulose, can be used in addition or in place of interexigent Mica Sodium curhm\metHvl ccllukne AitufHiicus ciav ! Amine-modified montnuiniUwute day gel . Weight Percent n( Tot.il Dry StMhJ* 15.11 (1.5 1.5 o.: " SCMC. SCMC is preferred only because it enhances the binder and docs not detract from the non-leveling 10 Except where noted, the source of the SCMC for the properties of the attapulgus day. Similarly, other non leveling agents may be used, as iong us they are non Examples tested was Hercules Incorporated, the partic ular brand name being "CMC 4HI" having, in a 1 per swelling and generally have the viscosity characteristics cent solution, a viscosity range at 25"C of between of the attapulgus day. Also colloids other than the about 400 and 1.000 cps. The degree of substitution modified montmorillonite gel or xanthan gum are ac 15 range was between 0.3H and 0.48. ceptable if their viscosity behavior is'similar to that of the day gel or the xanthan gum. The modified montmorillonite clay gel used in Exam ple No. 1 and all the following Examples was"Bentone Thus, to make a dry stored topping grade joint com LT" obtained from NL Industries Incorporated, having pound. a mixture of the above-identified ingredients is a specific gravity of 1.8. a weight per gai. of 15 lbs., and prepared as explained below. This can be made either 20 viscosity characteristics illustrated in FIG. 1 for a 2 per with calcium carbonate or calcium sulfate dihvdrate as cent solution of the gel. The data identified on the a filler, so as to harden by drying, or with a calcium sul curve has been arbitrarily assigned for a yield value fate hemihydrate filler, so as to harden by setting. The equal to zero, but in actuality it has been found that the taping grade can be made from an identical formula, static yield value of the gel equals about 35 dynes per except for the amounts of the conventional binder and 25 square centimeter. Both the differential and apparent thickner. For the all-purpose grade, the day or the col viscosity indicate it pseudoplastic nature. loid can be omitted. Any one of the SCMC. the ciav. The attapulgus day for all Examples was "Attagel or the colloid can be omitted in making ready-mixed 40" obtained from Engelhard Products, having an aver joint compound which is stored wctT age particle size of about 0.14 microns, a bulking value The remaining components of the joint compound 30 of 19.7 lbs. per cal;, a pH of between about 7.5 and 9.5, are conventional, non-critical. and are readily apparent a bulk density of between about. 19 to about 22 lb. per from the literature, which also teaches the amounts to cu. ft., and a B.E.T. surface area of about 210 m.vgm. be used. Various fillers have already been discussed, "Attagei 50" supplied by the same source is also ac including calcium carbonate, caicium sulfate dihy ceptable. as it has similar properties. The viscosity be drate. otherwise known as landolaster or terra alba, and 35 havior of a 20 percent solution of the attapulgus clay calcium suifate hemihydrate. The filler may constitute is shown in FIG. 2. The day is rheopecuc in nature, as between about 37 to about 92 percent of the total non shown by time-dependent viscosity studies. The static volatile solids weight. Still other conventional ingredi yield value is 622 bynes per square centimeter. ents. disclosed in said L'.S. Pat. No. 3.297.601. include To determine the acceptability of Example NO. I as the binder, a thickener, mica, and various preserva 40 a substitute for an asbestos-containing formula, it was tives. The binder thus may be polyvinyl alcohol, various mixed with water to make a joint compound having a starches, polyvinyl acetate, casein, soy protein, or mix consistency of about 65-68 cc. per 100 grams at a vis tures of these. Preferably the binder comprises from cosity of 550 Brabender units measured on a VC-3 Bra- about 1 to about 7 percent of the total dry weight. bender at about 77CF. This VC-3 Brabender is a com Common thickeners are hydroxvpropyl methyicellu- 45 mercially available viscometer equipped with a 250 lose. hydroxvethylcelluicse. hydroxyethvl methyicellu- centimeter-gram torsion head operated at a 75-78 lose. alginates, and sodium carboxymethyicellulose. r.p.m. spindle speed. Example NO. 1 was then tested Preferably the thickener is present in an amount be for workability and check-cracking, along with a con tween tween about 0.2 and 1 percent. The mica may be be about S and about 42 percent of the total dry 50 ventional asbestos-containing joint compound as a con trol. Workability is' the ability of the joint compound to solids weight. The preservatives constitute a very minor be manually troweled onto wallboard. and involves portion of the weight, as is weil known. such features as slip and resistance to flow. This prop To further illustrate the invention, various examples erty was ascertained in all EXAMPLES of this applica are set forth os preferred embodiments. These exam ples arc not intended to be limiting^ but can be ex 55 tion by the subjective testing of the compound in ques tion by skilled applicators against known standard joint panded as noted above. compounds. Check-cracking was measured for all EX EXAMPLE NO. I AMPLES by screeding a 'm inch thick coating, four inches across and eight inches wide, on pieces of wall- A topping grade joint compound was prepared in 60 board. which are then stored horizontally in a 75*F.. powder form according to the following formula: 10 percent relative humidity room for several hours. Drying was enhanced by repeatedly passing the sam Ingredient Calcium carbonate filler Poivvmvt alcohol h*mJer Hvdroftyeihyi ccIIuUm* tiuckcncr Preservative* Weight Percent of Total Dry Solid* 7V.9 1..1 0.* a* ples under a fan positioned about 3 feet above the coat ings. The dry coatings were inspected visually for 65 cracks. The conventional joint compound used as a control was that marketed by United States Gypsum Company under the name L'SG Joint Compound Top ping. This comprised, as the binder, a mixture of poly- / 90 ItO cO 3,891,453 56 vinyl alcohol and polyvinyl acetate totaling 2.4 percent cohol. The weight percents were the same as in Exam of the total nonvolatile solids. about 65 percent cul- . pic NO. I.;as were the remaining ingredients. Results carbonate filler, about 26 percent mica, about 5.5 were comparable to the results of EXAMPLE NO. i. percent asbestos, and miscellaneous preservatives. Example NO. I was found to be approximately equiv 5 ! EXAMPLE NO. 8 alent to the above-described conventional, asbestoscontaining joint compound, in workability and resis tance to check-cracking. A powdered form, lacing grade of joint compound was prepared by using the formula of EXAMPLE NO. I, except that the hinder was increased in amount to EXAMPLE NO. 2 the level of 3.5 percent, with a corresponding reduction 10 in the weight percent of the filler. Workability and A similar powdered topping grade can be prepared which differs primarily in the elimination of the monl- crack resistance was comparable to Example NO. 1. moriilonite clay gel. The following formula No. 2 was tested for cracking and workability, enough water hav ing been added to create a consistency of 73 cc. per 100 grams at a viscosity of 540 Brabender units: EXAMPLE NO. 9 An all-purpose grade of joint compound was pre pared from the formula of Example NO. 1. by increas ing the weight percent of the binder to the level of 5.5 percent, by decreasing the weight percent of the filler Ingredient Weight 5 of Total Dry Solids to the level of 74.9 percent, and by omitting the clay 20 gel- Sufficient slip was realized from the attapulgus CjJcHim carbonate filler 80.1 clay. If a texturing effect is required, the amount of clay Polwtml alcohol binder Hvdraxvethvi cellulose thickener Preservatives ' 1.0 0.8 0.5 must be at least 2 percent, with a corresponding change in the amount of filler. Workability and crack- Mica and sencue SCMC Atupuigus clay 15.0 0.6 resistance was again found to be comparable to Exam- 2.0 25 pie NO. 1. Amine-modified montmorillomte 0.0 clay gel EXAMPLE NO. 10 A ready-mixed joint compound suitable for wet stor It was found that the resulting joint compound was age was prepared from the following formula, which it slightly inferior to the control both in bonding and mix 30 will be noted is similar to the formula for Example No. ing. However, these deficiencies can be overcome by 1. Because of the large amount of binder, the Example raising the amount of binder to 1.5 or 2.0 percent, and was an all-purpose joint compound. by mixing with a drill rather than by hand. EXAMPLES NO. 3-6 35 Additional grades of SCMC can be used as the water- , Ingredient Weight * retention aid. other than "CMC 4H1", provided the de gree of substitution (D.S.) is less than 0.7. The amount of viscosity does not appear to be a factor, as will be ap parent from the following Examples. 40 The same formula and weight percents were used in EXAMPLE NO. I. except that SMC "CMC 2." "CMC 3M5T." "CMC 4M6." and "CMC 41 A." respectively, were used in place of "CMC 4HI". All of these were manufactured by Hercules, and had the following prop- 4^ Calcium carbonate filler Poiwihvi acetate binder (as in EXAMPLE NO. 7) Hvdroxyethyl cellulose thickener Preservatives Mica and sericite SCMC Attapulgus dav Amine-modified monimoriikjmte gel 76.6 5.5 0.8 0.1 15.0 0.5 1.0 0.5 ernes. Enough water was added to provide a consistency of 60 cc. per 100 grams, at a viscosity of 600 Brabender units. The resulting ready-mixed compound was found Example Viscosity Range No. SCMC D.S. at 2S*C (cp) 50 to have acceptable crack resistance, and its working ca pabilities were adequate for application by hand tools. 3 -CMC 2" 0.IS-O.2S 800-1600 at 1% 4 -CMC 0.25-0.4 200-500 at 25 3M5T- 5 -CMC 4M6" 0.38-0.4* 300-400 at ? 6 -CMC 41 A- 0.38-0.48 300-1200 at 25 In addition, a ready-mixed joint compound can be prepared from the immediately preceding formula, by omitting the SCMC. by increasing the amount of filler, 55 and by mixing with water to achieve a consistency of 53 cc. per 100 frams. at a viscosity of 600 to 650 Bra Each of EXAMPLES 3-6. when made into the com pound by mixing with water, had workability and crack bender units measured on the VC-3 Brabender. Work ability and crack-resistance are comparable to that of resistance that was substantially equivalent to these gg EXAMPLE NO. 1. properties provided by Example 1. EXAMPLE NO. II EXAMPLE NO. 7 A setting type of joint compound fully comparable to EXAMPLE NO. 1 wus made by substituting CaSO^V6H-0 for the CaCOi in that example, and by sub stituting polyvinyl acetate of the type disclosed in aforesaid U.S. Pat. No. 3.297,601, for the polyvinyl al- Calcium sulfate dihvdratc (landplaster) can be sub stituted for the calcium carbonate filler in the firststated formula for Example No. 10. The remaining ingredienta and preparation are the same, there being, however, a slight change in percentage of ingredients; 3,891,453 78 Ingredient Weight 4 This formula can be altered by using the same amount of "CMC-2" instead of "CMC - 4HI", except that it must be thinned to about 500 Brabenders. Landplaster filler Polvvmyi jcruie binder Us m EXAMPLE NO. 7) Hydroxyethyl ccUuIom: thickener Preservative! Mica and seriate SCMC Attapuigus day Amine-modified montmoniUinite gel 73.4 Also a comparable ready-mixed, all-purpose joint 5.0 5 compound can be obtained from Example 13's formu lation by substituting the polyvinyl acetate binder at an U.H 0.05 increased level of 5.5 percent, decreasing the filler cor 160 respondingly, and adding water to make the wet mix. 0.25 4.0 the amount of water being sufficient to provide a con 0.5 10 sistency of 60 cc. per 100 grams at 600 8rabcnder units viscosity. Adequate crack resistance is obtained, and working properties are suitable for application by hand In this case, the SCMC was "CMC-2"obtained from tools. Comparable results are achieved in this readyHercules, which is identified in Example No. 3 above. mixed formulation regardless whether the filler is cal When water is added to achieve a consistency of 65 15 cium carbonate or landplaster. cc. per 100 grams at a viscosity of 620 Brabender units, a ready-mixed all-purpose grade joint compound is pro EXAMPLE NO. 14 duced which is particularly useful for manual applica A dry powder topping grade can be prepared from tion. the following formula. 20 EXAMPLE NO. 12 It was further found that the previous Example can Ingredients Weight % be further modified so as to omit the SCMC. The fol lowing formula was used: Calcium carbonate filler 25 Polyvinyl alcohol binder Polyvinyl acetate binder 65.94 0.3 1.6 Hydroxyethyt cellulose thickener 0.1 IngrcdwnO Weight Preservatives Mica and seticite 0.36 25.0 Landplaster filler Polyvinyl acetate hinder . (as in EXAMPLE NO. 7) 79.6 4.5 Sodium carboxymethyi cellulose Attapuigus day 30 Xanthan gum Q.O 3.0 2.0 Hydroxyethyl cellulose thickener 0.S Preservatives 0.1 Mica and senate SCMC Atupulgus day Amine-modified montmonllontte gel 10.7 The Xanthan gum can be obtained from Kelco Com 0.0 4.0 pany under the trade name '`Kelzan " and has the fol 0.3 lowing properties. It is a linear polymer with an M.W 35 in excess of 1 million, comprising a B-linked backbone containing D-glucose, D-mannose- and D-giucuronic Water was added to produce a consistency of 58 cc. per acid with 1 D-mannose side-chain unit for everv eight 100 grams at a viscosity of 630 Brabender units. The sugar residues arid 1 D-glucose side-chain residue for resulting all-purpose ready-mixed joint compound was found to have adequate crack resistance. Working 40 every sixteen sugar residues. The molar ratio glucose to D-mannose to D-giucoconic acid n of Dabout properties were slightly inferior, but thinning the joint 2.8/3.0/2.0. In water it forms a hydrophilic colloid, la compound to a viscosity no greater than 550 Brabender viscosity is essentially stable at about 1000 cps fro* 0* units produces acceptable working properties. to 100C and from a pH of 1 to 11. FIG. 3 illustrates EXAMPLE NO. 13 the viscosity curve of Kelzan for a 1 percent concentra 45 tion, and particularly its pseudopiastic nature. The It has been found that the attapuigus clay can be curve is reversible. omitted in at least certain instances. The following is a When water is! mixed in by a drill at the joh km to representative example of a dry powder, all-purpose give a consistency of about 56 cc. per 100 grams at formulation. 50 about 580 Brabender units, the result is pound suitable for a manual application. a jotnt com ' EXAMPLE NO. 15 G^OU 0Jf,7 Ingredients Weight % It is possible to drastically reduce the amooat of Calcium carbonate filler Polyvinyl alcohol binder Hydrosyethyi cellulose hinder Preservative* Mica and scticu* Sodium carhneyirsethyl cailuiau Attapuigus day Amine-modified mommoriilomte day gel 15.3 1.5 55 filler, to increase the amount of mica, and to add k*> oiinite clay, in the formulations for the previous Exam 0.1 ples. Thus, to rriake a ready-mixed all-purposo joint 0.7 10.6 compound, water was added to the following: 0-5 0.0 0.6 60 Ingredients Weight b At the job site, water is added to produce a consistency of 72 cc. per 100 grams at a viscosity of 580 Brabender 65 units. The result is a joint compound having acceptable crack resistance and workability suitable for manual application. Calcium carbonate filler Polyvinyl acetate binder (as in EXAMPLE NO. 7) Hvdroxyetiiyi cellulose thickener Preservatives Mica and scricite SCMC Auupulgus day Amme-modified mommoriilomte gd Kaolinite clay 37.3 SJ 0.3 O.I 41.3 05 4.0 0.0 10.0 1 3,891,453 9 10 The SCMC of this Example was "CMC-2" identified in said water-holding agent is sodium curboxymcthvi- detail in the discussion of Example No. 3. The consis tency was found to be 63 cc. per 100 grams, at 500 Bra- ccllulose having a degree of substitution less than about 0.7. ; benders units viscusity. The working characteristics 3. The composition as defined in claim 3. comprising and crack resistance were found to be acceptable for 5 both said water-holding agent and said slip-inducing manual application of this joint compound in areas of colloid. high humidity. ' 4. The composition as defined in claim 3, wherein It was also found that Example 15 can be varied by deleting the SCMC and reinstating the modified mont- said slip-inducing colloid is modified montmoriilonite clay gel. ; morillonite gel. so that the amount of attapulgus clay is 2.0 percent, and the amount of gel is 1.0 percent. The remaining 1.5 percent is used in increasing the filler. The resulting joint compound is acceptable if used at about 500 Brabender units. 10 5. The composition as defined in claim 3, wherein said slip-inducing colloid is xanthan gum. 6. The composition as defined in claim 3. wherein said water-holding agent is sodium carbaxymethvl- Although the invention has been described in con nection with certain preferred embodiments, it is not intended that it be limited thereto. For example, small amounts of asbestos when added to the invention will 15 cellulase having a degree of substitution less than about 0.7. i 7. The composition as defined in claim 1, wherein said filler is calcium carbonate. create an acceptable compound, provided the amount 8. The composition as defined in claim 1, wherein does not exceed the limits imposed by OSHA stan dards. Thus, it is intended that it cover all equivalents, 20 said filler is calcium sulfate dihvdrate. 9. The composition as defined in claim 1, wherein alternate arrangements, and embodiments as may be said filler is calcium sulfate hemihydrate. included within the scope of the following claims. 10. The composition as defined in claim 1, wherein What is claimed is: said binder is a polyvinyl acetate emulsion. 1. A composition which when mixed with water forms a non-leveling joint compound having properties 25 11. A ready-mixed non-leveling joint compound hav ing properties suitable for use in coating joints between suitable for use in finishing joints between wallboards gypsum wallboards even when free of asbestos fibers, even when free of asbestos fibers, comprising the fol comprising the following ingredients in amounts based lowing ingredients in amounts based on the total dry on the total dry weight of the composition: weight of the composition: 30 water, a filler selected from the group consisting of calcium a filler selected from the group consisting of calcium carbonate and calcuim sulfate in an amount of be carbonate and calcium sulfate in an amount of be tween about 37 and 92 percent; tween about 37 and 92 percent; a binder in an amount of between about I and 7 per a polyvinyl acetate emulsion in an amount of be cent; 35 tween about l and 7 percent; attapulgus clay in an amount of between about 0.5 a slip-inducing colloid in an amount of between and 6 percent; and about 0.1 and 2.0 percent selected from the group at least one ingredient selected from the group con consisting of modified montmoriilonite clay gel and sisting of: xanthan gum; and a water-holding agent in an amount of between about 40 attapulgus clay in an amount of between about 0.5 0.1 and 2.0 percent; and and 6.0 percent. a slip-inducing colloid in an amount of between 12. The composition as defined in claim 11, addition about 0.1 and 2.9 percent selected from the group ally comprising sodium carboxymethylcellulose in an consisting of modified montmoriilonite clay gel and amount of between about 0.1 and 2.0 percent. xanthan gum. . 45 2. The composition as defined in claim 1, wherein t af 50 55 60 8 lJtO U O ttO 65 A TTAG-ec u cJU~ ..Skrr.,^Q^ (otf) y//^ o t *-. Cl r*r^^C JL^ GP031 0 Urf i-h.bj .m n j mu ;--wmi i--IHMilMW ------ Questions directed to us by the commissioners were: 1. What substitute materials are we using in place of asbestos? 2. How many available substitute materials for asbestos in joint treatment compounds are there? 1 1 1 3. What safety tests have we performed on the substitutes (toxicological tests) and hew are we monitoring the new materials to be sure there is- no asbestos in our finished products? (The implication was asbestos as a contaminant in another mn t-o r-i => t _ * .. ...--------- ! -- ------ - 1 1 1 M 4^_ What was the percentage of asbestos in our farmer comaounds? | 5. To our knowledge, which of the approximately 100 patching compound producers we mentioned in our statement now offer asbestos-free products? ;. 6. Do we have any patents on our non-asbestos formulations and, if so, what is the licensing availability? 7. Do we have any household consumer reactions to bur changes in formulation? : 8. Do we do any private labeling work for ,consumer marketing organizations on these compounds? Do we know of anyone -e-I-se--who-does*?---------------------- **-----............ -- --- ' 9. Back in the days when we were producing patching compounds containing'asbestos, did we utilize various types of asbestos from a variety of suppliers? If so, were the various types of material identifiable back to the source of supply? (The purpose here appears to be a cataloging of types of supply sources so that, by analyzing samples of asbestos- _ containing patching compounds, an investigator could ' identify the source of asbestos supply.) 10. Will there be changes in manufacturing costs and resulting pricing of our products due to the formulation changes away from asbestos? 11. Is the r.cv product mcro difficult to apply? 12. We stated in our presentation there are approximately 100 patching compound manufacturers. Would we please supply a list of names and addresses of as many of these as we can? n ^ O i li Ct I f C t iO GP031 0371