Patent ID: 7041427

Claim:
A heat-sensitive lithographic printing plate precursor comprising (i) a support having a hydrophilic surface or which is provided with a hydrophilic layer and (ii) a coating provided thereon, wherein the coating comprises a polymer that is soluble in an aqueous alkaline solution and that comprises at least one chromophoric moiety having a light absorption maximum in the wavelength range between 400 and 750 nm, the chromophoric moiety having a structure according to any of the following formulae I to VI: wherein l is 0 to 3; m 0 to 4; n is 0 to 3; o is 0 to 2; x and y are independently 0 or 1; each R 1 and R 2 is independently selected from the group consisting of alkyl, aryl, —G 1 , —L 1 —G 1 , —CN, a halogen, —NO 2 , —OR a , —CO—R d , —CO—O—R a , —O—CO—R d , —CO—NR d R e , —NR d R e , —NR d —CO—R e , —NR d —CO—O—R a , —NR d —CO—NR e R f , —SR a , —SO—R a , —SO 2 —R a , —SO 2 —O—R a , —SO 2 —NR a R b or wherein two adjacent radicals R 1 together form a condensed carbocyclic or heterocyclic ring; each R 3 and R 4 is independently selected from the group consisting of hydrogen, alkyl, aryl, —CO—R d , —CO—O—R b , —CO—NR g R h and —L 2 —G 2 ; R 11 , R 12 and R 13 are independently selected from the group consisting of hydrogen, alkyl or aryl; each R 14 is independently selected from alkyl or aryl; with A, A 1 , A 2 , L 1 and L 2 being a divalent linking group; G 1 , G 2 and G 3 being a solubilizing group selected from —COOH, —PO 3 H 2 , —O—PO 3 H 2 , —SO 3 H, —O—SO 3 H, —SO 2 —NH 2 , —SO 2 —NH—R c , —SO 2 —NH—CO—R c and salts thereof; R a , R b and R c being an alkyl or an aryl group; R d , R e , R f , R g and R h being hydrogen, an alkyl or an aryl group; wherein the chromophoric Q, Q 1 and Q 2 are independently selected from the groups consisting of wherein h is 0 to 5; i and k are independently 0 to 4; j is 0 to 2; * represents the bond between the chromophoric group and the polymer; each R 9 , R 9 ′, R 9 ′ and R 10 is independently selected from the group consisting of alkyl, aryl, —G 1 ′, —L 1 ′—G 1 ′, —CN, a halogen, —NO 2 , —OR a ′, —CO—R d ′, —CO—O—R a ′, —O—CO—R d ′, —CO—NR d ′R e ′, —NR d ′R e ′, —NR d ′—CO—R e ′, —NR d ′—CO—O—R a ′, —NR d ′—CO—NR e ′R f , —SR a ′, —SO—R a ′, —SO 2 —R a ′, —SO 2 —O—R a ′, —SO 2 —NR a ′R b ′ or wherein two adjacent radicals R 9 , R 9 ′ or R 9 ″ together form a condensed carbocyclic or heterocyclic ring; each R 5 , R 6 , R 7 , and R 8 is independently selected from the group consisting of hydrogen, alkyl, aryl, —CO—R d ′, —CO—O—R b ′, —CO—NR g ′R h ′ and —L 2 ′—G 2 ′; with L 1 ′ and L 2 ′ being a divalent linking group; G 1 ′ and G 2 ′ being a solubilizing group selected from —COOH, —OH, —PO 3 H 2 , O—PO 3 H 2 , —SO 3 H, —O—SO 3 H, —SO 2 —NH 2 , —SO 2 —NH—R c ′, —SO 2 —NH—CO—R c ′ and salts thereof; R a ′, R b ′ and R c ′ being an alkyl or an aryl group; R d ′, R e ′, R f ′, R g ′ and R h ′ being hydrogen, an alkyl or an aryl group.