Photographic films

Abstract

Anti-static photographic films comprise a self-supporting synthetic plastics film base, such as a polyethylene terephthalate film, having superimposed on at least one side a gelatin-containing subbing layer and a radiation-sensitive layer superimposed on the gelatin layer, in which an anti-static material is included in the gelatin-containing subbing layer or being interposed as a layer between the gelatin-containing subbing layer and the radiation-sensitive layer, said anti-static material comprising a polymer or copolymer containing repeating units of the formula: ##STR1## wherein R represents hydrogen or methyl, R.sup.1 represents methyl or ethyl, R.sup.2 and R.sup.3 each independently represent methyl or ethyl or R.sup.2 and R.sup.3 taken together represent --CH.sub.2 CH.sub.2 OCH.sub.2 CH.sub.2 -- or --(CH.sub.2).sub.n -- where n represents 4, 5 or 6, A represents an alkylene or substituted alkylene group and X.sup.- represents a chloride or acetate ion, said polymer or copolymer having an average molecular weight in the range 5,000 to 2,000,000. Preferred anti-static materials include a copolymer of equimolar amounts of trimethyl-.beta.-methacryloyloxyethyl ammonium chloride and styrene; a copolymer of equimolar amounts of ethyldimethyl-.beta.-methacryloyloxyethyl ammonium bromide and methyl methacrylate; a copolymer formed from equimolar amounts of trimethyl-.beta.-methacryloyloxyethyl ammonium acetate and styrene; a copolymer formed from 15 mole % trimethyl-.beta.-methacryloyloxyethyl ammonium chloride and 85 mole % styrene; a copolymer formed from 50 mole % ethyldimethyl-.beta.-methacryloyloxyethyl ammonium bromide and 50 mole % methyl methacrylate and a homopolymer of trimethyl-.beta.-methacryloyloxyethyl ammonium chloride.

Description