| 摘要 |
PURPOSE:A composition to be applied to a photograph constituting layer, having improved stability of a coating solution, obtained by blending a carboxyl group- containing hydrophilic polymer with colloidal silica and polyvinyl pyrrolidone. CONSTITUTION:A carboxyl group-containing hydrophilic polymer, preferably a copolymer of >=4C ethylenic unsaturated copolymerizable monomer and maleic anhydride, is blended with colloidal silica obtained by dispersing ultrafine particles (particle diameters of 5-60mmu) of silicic anhydride into a dispersion medium consisting essentially of water and polyvinyl pyrrolidone (preferably a molecular weight of 8,000-400,000) in a weight ratio of (1:0.001)-(1:0.150). The composition has the total solid concentration of the individual components of 1.0-10wt% and has a pH of <=9. In mixing, the aqueous solution of the colloidal silica is pre-blended with the aqueous solution of the polyvinyl pyrrolidone, and preferably the blend is added to the aqueous solution of the hydrophilic polymer. |
