PURPOSE: To obtain a printing plate causing no printing stain and having superior printing resistance by subjecting a photosensitive material using a photosensitive composition contg. resol type phenol resin having a specified percentage or more of dibenzilic ether bonds to exposure, development and curing by heating to a specified temp. or above.
CONSTITUTION: Phenols represented by the formula [where each of R1, R2 and R3 is H, halogen, OH, NO2 1W20C alkyl, alkoxy, acyl or (substituted) phenyl] are reacted with aldehyde such as H2CO or ketone to obtain resol type phenol resin having -CH2OCH2- bonded to each phenol ring by ≥15mol% of the total amount of -CH2OCH2-, -CH2- and -CH2OH. A soln. of a photosensitive composition contg. diazo resin as well as the resol type phenol resin is applied to an Al plate and dried to produce a photosensitive material. This material is exposed, developed with an alkaline aqueous developer, and heated to ≥140°C. Thus, a printing plate causing no printing stain and having high printing resistance is obtd. by using the photosensitive material having superior developability and aging stability and curable at such a low temp.
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