Document 82mDnVpD8ow2pQYEyynmJLKyd

FILE NAME: US Gypsum (USG) DATE: November 1, 1966 DOC#: USG072 DOCUMENT DESCRIPTION: 1966 Progress Report from USG Research Center re asbestos substitute ^66 " II / \I Ut< 1TATZ2 GsrSUM Z Z 'A r '^ r r azizAsca czrna ?H CG ^O E?0RT 4 v I l- 7 - c > > , a 4 tr ? a m M 1 A 9 a - Asbestos. S u b s titu te v/cr:< was sta rte d bo in v e stig a te su b stitu te s Tor asbestos in* I z L r .z ;..;.l17^ r : m e f i r s t se rie s was xa.ce with. very f i r e " ? ! (C as-0 -2 ii M-5, Cabot C or?.) in a nor.-casein all-purpose cccpcuns An a ir -flo a te d s la y ( I x c e ilo , There sen-Vieincar.) was also used ir. tr.ese ccrpcunds to irp rcve a p p lic a tio n p ro p e rtie s. None c f the f i r s t experim ental ccrpcur.ds icoiced as good as the A?-28`*A csr.tro they a ll* had slow wetdown and very haavy r i s i n g . In trow eling tasts the e x p e rire n ta i compounds f e l t haavy i n i t i a l l y , then broxs down to g iv e a s o f t e r , smoother spread but also core tender.sy to flow and to wipe o f f the board. The ta s t r e s u lts fo r tha f i r s t s e r ie s , AP-291A-2, shewed th at ths s i li o a would have to be used at le s s than the - e f t le v e ls t r i e d . The A?-293 A-D s e r ie s , containing ths s i l i c a at 1-355 le v e l, also snowed c h a r s e te r is tic s o f heavin ess, s tic k in e s s and excessive f l : Cr. one fa v o ra b le s id e , the cccpound. containing 1% s i l i c a did have a s o fte r , scsccr.er f e e l a ft e r i t s v is c o s it y breakdown under the -rowel. The A2293A-D s e r ie s shoved th at a c o llo id a l grade of a tta tu lr u s cla y ( A tta g e l ttO, M inerals and C h e c ic a ls P h ilip ? C crp .) was not successful as a d ire ct replacscent fo r asbestos in a nor.-casair. all-p u rp o se cocpound. Use o f the c la y a t Q .5--*S of the fe r r u le gave' lev; c o n siste n cy ccrpcunds which rixe d w ell but had heavy, zz stic k y troviel a p p lic a tio n prop erties and tenced to flow cr. one crew el. The cccpcur.ds h ^ s- *ccd bend to tape and f a i r cnac.< crac.resistance. Tris in v s s t ig a t is n w i ll be ccntinued as kocwladre of other peter.: ascsdys~ suestitutaa is dissevered^ i t seers p o s s in e ona t r.o~ s: - T jj --11 vr* i 1 -* ^i m e reouarecents and th at cccsin a cions of ra t r ia ls such as described ih th is report wilu. bs .ss-lst--to rep; asbestos. A rsplaoecent f o r asbestos in Jo in t corpour.ds is d e sira c le becau: it" would T irlra o th i tre sen t s o r tia te dependence on t r i s raw ataria i. tien, is a p o s s lo ilit y th at assesses ray be fae^ared a h a ra rd o u a c a t a r ia ! ana it o use c ro n ic i e s c , e lic in a ted ir severely l i r a ta d . As an e tn ic a l p ro p o sitio n , i f ascestcc i : f j e t "naraygetig ^ fry-- n. nsa-io.-i I t Shame os replaced In sp ice or its uniou and v aiu a sla oroasrti.es. Rl5H| *g i ^PLAINTIFF'S < & S , EXHIBIT ^ O u. p - v / t . ^ . , 1 - 7 X : / K -.l