The present application relates to a positive-working heat-sensitive lithographic plate. The infrared heat-sensitive image recording composition of the plate comprises a resin having self-dissolution inhibiting property and an infrared absorber. The resin having self-dissolution inhibiting property is an alkali-soluble resin that contains phenolic hydroxyl group, and carbamate or thiocarbamate group that has strong electron-absorbing ability. The advantage of the present application is that it requires no dissolution inhibitor when preparing the infrared positive-working heat-sensitive CTP plate. The mechanism could be understood but not limited to that the carbamate or thiocarbamate group contained in the resin has a dissolution inhibiting effect on the phenolic hydroxyl group in the resin, reducing the solubility of the resin in an alkali solution.
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