PHOTOGRAPHIC MATERIALS

1278721 Polymers of N-trishydroxymethylmethyl acrylamide EASTMAN KODAK CO 26 March 1970 [2 April 1969] 14873/70 Heading C3P [Also in Division G2] Polymers and copolymers containing units of the formula in which R is H or CH 3 are obtained in water or water/alcohol -mixtures with a free radical catalyst. Photographic emulsions contain polymers as defined above. Suitable comonomers are those whose polymers increase the covering power of the silver halide, e.g. acrylamide, N-(2-hydroxyethyl) acrylamide, vinyl pyrrolidone or N- acrylylmorpholine; alternatively a homopolymer may be mixed with a homopolymer of such a monomer or with a polysaccharide e.g. dextran, poly (vinyl-#-hydroxyethyl carbamoylmethylcarbamate) or succinoylated polyvinylalcohol. The binder is gelatin or a mixture thereof with an acrylate/acrylic acid/ sulpho acrylic ester copolymer or acrylate/acrylic acid/acetoacetylester copolymer. The emulsions which may also contain sensitizers, hardeners, stabilizers, antifoggants, speed increasing materials or plasticizers are coated on to supports, particularly polyesters, and dried.