| 摘要 |
<p>Alkali soluble copolymers, imageable elements useful as lithographic printing plate precursors that contain the alkali soluble copolymers, and methods for forming images using the imageable elements are disclosed. The alkali soluble copolymers comprise, in polymerized form: (a) N-phenylmaleimide, N-cyclohexylmaleimide, N-benzylmaleimide, or a mixture thereof; (b) acrylamide, methacrylamide, or a mixture thereof; (c) acrylonitrile, methacrylonitrile, or a mixture thereof; and (d) one or more monomers selected from the group consisting of monomers of the structure: CH<SUB>2</SUB>-C(R)-Z-X-NHC(O)NH-Y-R', in which: X is -[C(CH<SUB>3</SUB>)<SUB>2</SUB>]- or -[(CH<SUB>2</SUB>)<SUB>n</SUB>]-, in which n is 0 to 12; Y is o-, m-, or p- -[C<SUB>6</SUB>H<SUB>4</SUB>]-; Z is -[C(O)O]-, -[C(O)NH]-, or o-, m-, or p- [-C<SUB>6</SUB>H<SUB>4</SUB>]-; R is hydrogen or C<SUB>1 </SUB>to C<SUB>4 </SUB>alkyl; R' is -OC(O)-OR'', -OC(O)-Ar, or -OSO<SUB>2 </SUB>-Ar; R'' is C<SUB>1 </SUB>to C<SUB>12 </SUB>alkyl, C<SUB>1 </SUB>to C<SUB>12 </SUB>arylalkyl, C<SUB>1 </SUB>to C<SUB>12 </SUB>aryl, C<SUB>1 </SUB>to C<SUB>12 </SUB>alkenyl, or trimethylsilyl; Ar is C<SUB>6</SUB>H<SUB>5-n'</SUB>T<SUB>n'</SUB>, in which Ar has a total of six to ten carbon atoms; each T is independently selected from the group consisting of C<SUB>1 </SUB>to C<SUB>4 </SUB>alkyl, fluoro, chloro, bromo, iodo, trifluoromethyl, methoxy, and cyano; and n' is an integer from 0 to 5; and in which the copolymer is soluble in alkaline solutions having a pH greater than at least about 11.</p> |
