Document g2wNoJyEkajg7ypp8MpvoQwMV

Frigidaire Corporation Subsidiary of General Motors Corporation D A YTO N , OH IO..U.S.A. May 28, 1930. C A B L Z A D D R K ftt *T R IG ID A IR S" ALL CODBS V K O Dr. Robert A. Kehoe, U niversity of Cincinnati, C in cin n ati, Ohio. Dear Dr. Kehoe We have, in the p a s t , endeavored to keep a l l m a te r ia ls used in f in is h in g work a t the Moraine City P la n t, f r e e from le a d . In the p a s t white lead p a in ts were u sed , and v a rio u s leaded m a t e r ia ls , in v ario u s ways. These have a l l been rep laced by zinc pigm ents with the excep tion of the Duco prim er, which con tain s b a sic lead sulphate which i s , according to the re p o rts o f the duPont Company, in s o lu b le . f (j We lav e alw ays in s is t e d th a t th e f r i t from which; our p o rc e lain i s made be fr e e from le a d . T his was due to the f a c t th at t h i s f r i t was ground in a b a l l m ill to a very fin e s lu r r y w ith t i n oxJ.de and c la y . This ground f r i t i s put on the work by dipping or sp ray in g . The f r i t s used in the p a st fo r t h is purpose were not a c id proof; and did not co n tain any le a d . We are now able to purchase an a c id proof' f r i t con tain in g 1 to 1-1/2# of le a d . The lead i s placed in to a m e lt, which i s a g l a s s m ix tu re, and in the f i n a l co n d ition the lead i s probably p resen t a s s i l i c a t e . At any ra te the lead is in an in so lu b le fo r a . This f r i t i s ground, a s mentioned above, and then i s sprayed on to the work and baked at about 1500?. A fte r i t comes out the fin ish e d a r t i c l e i s a c id proof and i s not a ffe c te d by such ac id s a s h y d ro ch lo ric, t a r t a r i c , c i t r i c , a c e t ic , m a lic , and o x a lic . We would lik e very much to go to the use of t h i s type o f a c id r e s is t in g f r i t and i t i s p r a c t i c a l l y im p o ssib le to use a f r i t e n t ir e ly lead fr e e on account of the f a c t th at the fu s in g p o in t i s too high and our lin e r s a r e warped by such high h e at. By the addition of th is sm all percentage of lead to the m ixture, the fu sin g point o f the r e s u lt in g p o rc e la in i s brought in to working range and inasmuch a s the lead i s in an in so lu b le foxm, in both the f r i t s t a t e and in the f i n a l fu se s t a t e , we f e e l th at we w il l be j u s t i f i e d in going to t h is m a te ria l fo r use on our li n i n g s . We would lik e very much to have your opin ion in t h is m atter before we take any s te p s in follow ing out t h i s program. Everything i s progressin g very n icely with the flu o rid e r e fr ig e r a n ts; the only d i f f i c u l t y i s th at p ro g re ss seems kind o f slow when we are in such a hurry to work out the usage of F t * . With b e st re g a rd s. Very tr u ly y o u rs, FRIGIDAIRE CORPORATION Manager - Research and