Preparation of photosensitive block copolymer elements

Claim 1

A process for forming a solvent-soluble, photosensitive elastomeric element comprising applying to a sheet support a layer of a photosensitive, elastomeric composition to a dry thickness of from about 0.005 to about 0.25 inch, said composition comprising (1) at least 30% by weight of at least one solvent-soluble, thermoplastic, elastomeric block copolymer containing at least two thermoplastic, nonelastomeric polymer blocks having a glass transition temperature above 25° C. and an average molecular weight of 2000-100,000, and between said thermoplastic, nonelastomeric polymer blocks an elastomeric polymer block having a glass transition temperature below 10° C. and an average molecular weight of about 25,000 to 1,000,000, (2) at least 1% by weight of an addition-polymerizable ethylenically unsaturated compound containing at least one terminal ethylenical group, and (3) a polymerization-effective amount of polymerization initiator activatable by actinic radiation; laminating onto said layer a combination of (a) a strippable flexible cover sheet having coated thereon (b) a solvent-soluble, flexible, polymeric film, so that the surface of said film is contiguous to the surface of said layer.