Negative-working imageable elements and methods of use

A lithographic printing plate precursor comprising an aluminum-containing substrate having thereon an imageable layer comprising:

• a radically polymerizable component,
• an initiator composition capable of generating free radicals sufficient to initiate polymerization of free radically polymerizable groups upon exposure to imaging radiation,
• a radiation absorbing compound, and
• a polymeric binder that has an acid value of from about 20 to about 400 mg KOH/g and an all carbon backbone to which are attached the same or different pendant groups with the exception of pendant groups having ethylenically unsaturated free radically reactive groups, and that is represented by the following Structure (I):
• wherein m is at least 85 mol % and the sum of m and n is 100 mol %, R1 through R4 are independently hydrogen or methyl, X1 is one or more acetyl, phenyl other than styryl, N-carbazole, cyano, carboxy ester, or carboxy amide pendant groups, and X2 is one or more carboxy ester or carboxy amide pendant groups
• provided that when either R2 or R4 is hydrogen, both are hydrogen, and
• said initiator composition includes one or more diaryliodonium borate compounds, each of which is represented by the following Structure (IB):
• wherein X and Y are independently halo, alkyl, alkyloxy, aryl, or cycloalkyl groups, or adjacent X or Y groups can be combined to form a fused carbocyclic or heterocyclic ring with the respective phenyl groups, p and q are independently 0 or integers of 1 to 5, provided that either p or q is at least 1, and Z− is an organic anion represented by the following Structure (IBZ):
• wherein R1, R2, R3, and R4 are independently aryl groups.