| 摘要 |
The invention relates to photopolymerisable compositions comprising I) novel polymers, namely the products of the reaction of a) organic polyisocyanates and b) organic compounds containing at least about two active hydrogen atoms in the molecule, where the polymers obtained have been blocked by reaction with c) organic compounds containing precisely one active hydrogen atom on their terminal groups and these polymers blocked at the terminal groups have a viscosity of from about 5 to about 70 Stokes at 25 DEG C, determined on a 30% solution in a mixture of approximately equal parts of xylene, methyl ethyl ketone and ethylene glycol monomethyl ether, II) polymerisation initiators which can be activated by high-energy radiation, III) polymerisable, olefinically unsaturated compounds which can be polymerised in the presence of the polymerisation initiators, and IV) natural or synthetic rubberlike polymers. The unsaturated components may be an integral part of the polymer structure or can be separated as a mixture with the polymers and initiators. Relief images (pictures), in particular for printing, are produced by imagewise exposure through an original and subsequent development using a developer.
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