Photosensitive lithographic printing plate substrate layer - comprising free carboxyl gp.-contg. resin or salt and nickel salt combination

摘要

In a photosensitive lithographic plate, consisting of an anodically oxidised Al carrier, a hydrophilic substrate layer and a photosensitive layer, the substrate layer comprises a free COOH gp.-contg. water-soluble resin, (I) or its water-soluble salt, and a water-soluble Ni salt (III). (I) may be a carboxyalkyl cellulose, esp. CMC (pref.) carboxyethyl- or carboxypropyl cellulose, or a K- or Na-salt, or Na alginate, denatured starch, an acrylamide/acrylic acid-, acrylamide/methacrylic acid, vinyl pyrrolidone/acrylic acid- or a methacrylic acid copolymer, a hydrolysed vinyl acetate/maleic anhydride copolymer prod., a hydroxyalkyl acrylate/acrylic acid-, hydroxyalkyl acrylate/methacrylic acid-, hydroxyalkyl methacrylate/acrylic acid- or a hydroxyalkyl methacrylate/methacrylic acid copolymer. Use of (I) and (II) prevents foaming or efflorescence on treatment with automatic developing installations, even after long storage.