PROCESS FOR THE PRODUCTION OF LITHOGRAPHIC PRINTING PLATES

摘要

Process for the production of lithographic printing plates comprising (a) providing a lithographic substrate with a hydrophilic surface; (b) applying a negative working radiation-sensitive composition onto the hydrophilic surface, wherein the composition comprises: (i) one or more types of monomers and/or oligomers and/or polymers, each comprising at least one ethylenically unsaturated group accessible to a free-radical polymerization, (ii) at least one sensitizer which in the presence of at least one coinitiator and upon exposure to radiation of a wavelength of 300 to <480 nni or >750 to 1,100 nm initiates the free-radical polymerization of component (i); and (iii) at least one binder with acidic functional groups and is substantially not sensitive to the wavelength range of 480 to 750 nm; (c) image-wise exposure of the resulting negative working lithographic printing plate precursor to radiation selected from the wavelength range of 300 to <480 nm or >750 to 1,100 nm depending on the sensitizer or initiator system used; and (d) removing the non-irradiated areas by means of a treatment with an alkaline developer with a pH value in the range of 9 to 14 comprising (i) water, (ii) one or more alkali hydroxides in an amount sufficient for adjusting a pH value in the range of 9 to 14; and (iii) 1 to 30 wt. -% of at least one compound of formula (I) wherein R¹, R², R³ and R⁴ are each independently selected from C₁-C₁₂ alkyl groups and aryl groups, X is selected from -CH=CH-, -C=C-,formula (II), formula (III), and formula (IV), n + m results in a value of 2 to 30 and p + q results in a value of 0 to 30, wherein in the case of p + q ? 0 the ethylene oxide and propylene oxide units are present as blocks or randomly distributed.