Patent ID: RE41083

Claim:
A copolymer for use in coating compositions for printing plate precursors, the copolymer comprising units A, B, and a unit C comprising a cyclic terminal urea group, wherein unit A is present in an amount of about 5 to about 50 mol % and has the formula is represented by wherein R 1 is selected such that the homopolymer of A is alkali-soluble, unit B is present in an amount of about 20 to about 70 mol % and has the following formula is represented by wherein R 2 is selected such that the homopolymer of B has a glass transition temperature greater than 100° C., preferably a glass transition temperature in the range from about 100 to about 380° C., and the unit C comprising a cyclic terminal urea group is present in an amount of about 10 to about 50 mol % and has the formula is represented by wherein X is a spacer group which is preferably selected from the group consisting of (a) a —(CR 2 ) m — chain, (b) a —[CH 2 —CH 2 —O] m — chain; and (c) a —[Si(R 2 )—O] m — unit, wherein m is an integer between 2 and 12, the spacer group is connected to one of the carbon ring atoms of the cyclic urea unit or to one of the nitrogen atoms of the cyclic urea unit, and n is an integer between 1 and 5; and Y is a group selected from the group consisting of: wherein each R in units A, B, and C, the —(CR 2 ) m — chain, the —[Si(R 2 )—O] m — unit, and group Y represents a bond between the cyclic urea and the spacer group X, or is independently selected from hydrogen, aryl, (C 1 -C 12 ) alkyl, and or halogen.