| 摘要 |
<p>PROBLEM TO BE SOLVED: To use an aqueous binder allowing formation of a firm coating excellent in coating adequacy to provide an optical filter having a filter layer formed on a transparent support body, by including as the binder of the filter layer, gelatin having a specific range of viscosity of specific aqueous solution at a specific temperature. SOLUTION: This optical filter has at least a filter layer on a transparent support body. As a binder of the filter layer, gelatin where viscosity of 10 wt.% aqueous solution is in the range of 5-100 mPa.s at 25 deg.C is contained. Weight-average molecular weight of this gelatin used as the binder of the filter layer is in the range of 2000-50000. In addition, the filter layer is formed from an aqueous composition containing dye and the gelatin. Using a dye composition composed of the gelatin binder excellent in coating characteristic and pigment, the uniform filter layer without color nonuniformity is formed on the transparent support body, and thereby imparting a suitable color correction function to the optical filter.</p> |
