| 摘要 |
PURPOSE:To enhance preservability of images, by utilizing a color forming reaction taking place upon the the contact of a high molecular weight color former with a high molecular weight color developer. CONSTITUTION:A high molecular weight color former is a copolymer of a color former having a vinyl or vinylidene group (hereinafter referred to as a vinyl group) with other monomer, and is synthesized by bringing the color former having at least one active hydrogen atom of a hydroxyl group, an amino group or the like into reaction with a compound having an active group, e.g., a vinyl-containing acid halide, ester, halide or isocyanate. On the other hand, a high molecular color developer is a copolymer of a color developer having a vinyl group with other monomer, and is preferably a derivative of a phenol, benzoic acid, sulfone, amide or amide which has at least one acidic group. The high molecular weight color former and the high molecular weight color developer are used in a weight ratio of between 1:10 and 1:0.1, preferably, between 1:5 and 2:3. The coating weight is generally about 2-10g/m<2> in the form of solid components. |
