Patent ID: 8399172

Claim:
A negative-working lithographic printing plate precursor comprising a support and a photopolymerizable layer on said support, wherein said photopolymerizable layer contains a binder polymer that comprises, as a binder, a polymer compound having the urea bond in the main chain, having a hydrophilic group, and having a carboxylic acid content less than 0.05 meq/g, wherein said photopolymerizable layer contains an infrared absorber, a polymerization initiator, and polymerizable monomer, wherein a mass ratio between said binder polymer and said polymerizable monomer is 3/2 to 1/3, wherein said hydrophilic group comprises an alkylene oxide structure represented by the following general formula (I): wherein R represents a hydrogen atom or methyl; a is 1, 3, or 5; and 1 is an integer from 1 to 50, and wherein said polymer compound contains a structure in which the following (i) and (ii) are connected as repeat units: in (i), A represents —R 3 —(C n H 2n )—R 3′ —, R 3 and R 3′ represent phenylene, n is 1, and R 1 and R 1′ each independently represent a hydrogen atom, alkyl, aryl, or aralkyl, in (ii), B represents a divalent linking group, and R 2 and R 2′ each independently represent a hydrogen atom, alkyl, aryl, or aralkyl.