Infrared-sensitive composition for printing plate precursors

A lithographic printing plate precursor comprising:

• a substrate;
• and coated on the substrate, an infrared radiation-sensitive composition comprising:
• a polymeric binder,
• a free radical polymerizable system consisting of at least one polymerizable component,
• a compound capable of absorbing infrared radiation, an initiator system comprising an iodonium salt that is capable of producing free radicals;
• and
• at least 1% and up to and including 10% by weight, based on the infrared-sensitive composition, of at least one carboxylic acid having an aromatic moiety that is represented by:
• (1) formula (A), (B), or (C):
• wherein each of R5, R6, R7, R8 and R9 is independently selected from the group consisting of hydrogen, alkyl, aryl, halogen, alkoxy, hydroxyalkyl, carboxyalkyl, alkylthio, alkylsulfonyl, sulfonic, alkylsulfonate, dialkylamino, acyl, alkoxycarbonyl, cyano, and nitro, or R5 and R6, R6 and R7, R7 and R8, or R8 and R9 together optionally form an aromatic or aliphatic ring,
• R10 is selected from the group consisting of hydrogen, alkyl, aryl, hydroxyalkyl, carboxyalkyl, acyl, alkoxycarbonyl, alkylsulfonyl, and alkylsulfonate, or R10 and its bond together optionally form an electron pair, or R9 and R11 together optionally form a ring, R11 is an alkylene group of C1-C6 carbon atoms, or R10 and R11 together optionally form an aliphatic ring, and
• A is a heteroatom selected from the group consisting of N, O, and S;
• wherein Ar is selected from the group consisting of an unsubstituted aryl, a mono-substituted aryl, and a poly-substituted aryl group, and p is an integer from 1 to 5;
• wherein R4 is selected from the group consisting of hydrogen and a C1-C6 alkyl group, and wherein each of k and m is independently an integer from 1 to 5;
• (2) a combination of compounds represented by formulae (A), (B), and (C);
• or
• (3) a carboxylic acid having an aromatic moiety and that is represented by one of the following structures:
• wherein X is NR′, oxygen, or sulfur, Ar is any substituted or unsubstituted aryl ring. R′ is hydrogen or an alkyl group, and R is any substituent.