摘要 |
An aqueous alkaline developing system for alkaline-developable lithographic printing plates and a method for its use are disclosed. The developing system comprises one or more water-soluble suppressors of the following structure: <paragraph lvl="0"><in-line-formula>R1(CHOH)nR2 </in-line-formula>in which: n is 4 to 7; and either (i) R1 is hydrogen, aryl, or CH2OH; and R2 is alkyl group having 1 to 4 carbon atoms, CH2OR3 in which R3 is an alkyl group having 1 to 4 carbon atoms, CH2N(R4R5) in which R4 and R5 are each independently hydrogen or an alkyl group having 1 to 4 carbon atoms, or CO2H; or (ii) R1 and R2 together form a carbon-carbon single bond. The developing system is especially suited for developing imageable elements useful as lithographic printing plates. The developing system is especially suited for use with elements in which (1) the imageable layer comprises at least one phenolic resin or at least one polymeric compound having pendent sulfonamide groups, and (2) the substrate is aluminum or and an aluminum alloy.
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