Use of cinnamic acid groups containing acetal polymers for radiation-sensitive compositions and lithographic printing plates

A radiation-sensitive composition comprising

• (i) a copolymer comprising the units A, B, C, D and optionally E, wherein A is present in an amount of about 25 to 55 mol % and is of the formula
• B is present in an amount of about 0.5 to 25 mol % and is of the formula
• wherein R1 is selected from the group consisting of alkyl, aryl and aralkyl C is present in an amount of about 0.5 to 40 mol % and is of the formula
• wherein X is an aliphatic or aromatic spacer group, and Ac is an acidic group selected from the group consisting of —COOH, —SO3H, —SO2NR9R10 with R9 and R10 independently being selected from hydrogen and alkyl;
• and when X is phenylene, Ac can also be OH,
• D is present in an amount of about 20 to 70 mol % and is of the formula
• wherein Ci is selected from the group consisting of Ci-1, Ci-2, Ci-3 and Ci-4 which are represented by the following formulae
• wherein:
• k, m and n are integers independently selected from 0 to 5,
• R3, R4 and R7 are independently selected from the group consisting of alkyl, alkoxy, —COOR8, —NR9R10, —NH—CO—CH3, halogen, and cyano,
• R8 is selected from hydrogen and alkyl,
• R9 and R10 are independently selected from hydrogen and alkyl,
• R5 is selected from the group consisting of hydrogen, alkyl, aryl and aralkyl,
• R6 is selected from the group consisting of alkyl, aryl and aralkyl and
• Y is selected from the group consisting of alkylene, arylene and arylenealkylene;
• and
• E is present in an amount of about 0 to 50 mol % and is of the formula
• wherein R2 is selected from the group consisting of alkyl, aryl and aralkyl groups;
• and
• (ii) optionally at least one member selected from the group consisting of photosensitizers for photocyclo addition, diazo resins, colorants, exposure indicators, surfactants, stabilizing acids and plasticizers.

A radiation-sensitive element comprising (a) a substrate and (b) a radiation-sensitive layer wherein the radiation-sensitive layer comprises

• (i) a copolymer comprising the units A, B, C, D and optionally E, wherein A is present in an amount of about 25 to 55 mol % and is of the formula
• B is present in an amount of about 0.5 to 25 mol % and is of the formula
• wherein R1 is selected from the group consisting of alkyl, aryl and aralkyl
• C is present in an amount of about 0.5 to 40 mol % and is of the formula
• wherein X is an aliphatic or aromatic spacer group, and Ac is an acidic group selected from the group consisting of —COOH, —SO3H, —SO2NR9R10 with R9 and R10 independently being selected from hydrogen and alkyl;
• and when X is phenylene, Ac can also be OH,
• D is present in an amount of about 20 to 70 mol % and is of the formula
• wherein Ci is selected from the group consisting of Ci-1, Ci-2, Ci-3 and Ci-4 which are represented by the following formulae
• wherein:
• k, m and n are integers independently selected from 0 to 5,
• R3, R4 and R7 are independently selected from the group consisting of alkyl, alkoxy, —COOR8, —NR8R10, —NH—CO—CH3, halogen, and cyano,
• R8 is selected from hydrogen and alkyl,
• R9 and R10 are independently selected from hydrogen and alkyl,
• R5 is selected from the group consisting of hydrogen, alkyl, aryl and aralkyl,
• R6 is selected from the group consisting of alkyl, aryl and aralkyl and
• Y is selected from the group consisting of alkylene, arylene and arylenealkylene, and
• E is present in an amount of about 0 to 50 mol % and is of the formula
• wherein R2 is selected from the group consisting of alkyl, aryl and aralkyl groups;
• and
• (ii) optionally at least one member selected from the group consisting of photosensitizers for photocyclo addition, diazo resins, colorants, exposure indicators, surfactants, stabilizing acids and plasticizers.