| 摘要 |
PURPOSE:To obtain a printing plate having high sensitivity, superior printing resistance, etc. and capable of being developed with water by forming a photosensitive layer contg. photosensitive polyester consisting of a specified aromatic dicarboxylic acid, a dicarboxylic acid having a sulfonate group, and a specified diol on a support. CONSTITUTION:A lithographic plate is manufactured by forming a photosensitive layer contg. photosensitive polyester on an Al substrate or the like. The polyester consists of 5-45mol% dicarboxylic acid units (a) represented by formulaI(where each of m and n is 0 or 1, and at least one of them is 1), <=40 mol% dicarboxylic acid units (b) each having a sulfonate group such as 5- sodium sulfoisophthalate (ester), and diol units (c) represented by formula II (where H is a hydrogenated benzene ring, each of R<1> and R2 is 2-4 C alkylene, each of R<3> and R<4> is H or 1-6C alkyl, each of r and s is a number of 0-3, and t is 0 or 1). The lithographic plate can be developed with water or a weakly alkaline aqueous soln. and has superior chemical resistance, printing resistance and compatibility with ink. |
