| 摘要 |
PROBLEM TO BE SOLVED: To prevent the whitening of a non-image area, to ensure satisfactory printing resistance and to suppress the occurrence of a stain due to the lapse of time and a residual color by forming a middle layer contg. a high molecular compd. contg. specified repeating units on an Al substrate made hydrophilic by treatment and forming a positive type photosensitive layer on the middle layer. SOLUTION: A middle layer contg. a high molecular compd. contg. repeating units represented by formula I, II or III is formed on an Al substrate made hydrophilic by treatment and a positive type photosensitive layer is formed on the middle layer. In the formulae, R1 is H, halogen or alkyl, B is an arom. group, A is -COO-, -CONH- or -CON(CH3 )-, G is a trivalent combining group, D and E are individually single bonds or divalent combining groups, L is a divalent combining group, X and X' are acid groups each having a pKa of <=7 or their alkali metallic salts or ammonium salts, (t) is an integer of 2-4 and (m) is 2 or 3. |
