Abstract: Disclosed is a method for producing a water-developable photopolymer plate for letterpress printing comprising an exposure step, a development step and a post-exposure step wherein the photopolymer plate is brought into contact with a liquid containing a modified silicone compound and/or a fluorine compound during or after the exposure step.

Abstract: Disclosed is a method for producing a water-developable photopolymer plate for letterpress printing comprising an exposure step, a development step and a post-exposure step wherein the photopolymer plate is brought into contact with a liquid containing a modified silicone compound and/or a fluorine compound during or after the exposure step.

Abstract: A photosensitive constituent for a flexographic printing plate comprising a polyester film as support (B) and a photosensitive elastomer composition (C) and having an adhesive layer (A) therebetween, wherein the photosensitive elastomer composition (C) comprises, as essential components, (a) 50% by weight or more of at least one thermoplastic elastomer comprising a mono-vinyl-substituted aromatic hydrocarbon and a conjugated diene, (b) 5 to 40% by weight of at least one diene-based liquid rubber, (c) 1 to 20% by weight of at least one ethylenically unsaturated compound having 2 unsaturated bonds within its molecule, and (d) 0.1 to 3% by weight of at least one photopolymerization initiator, and wherein (1) the thermoplastic elastomer has an average ratio of vinyl bond units in conjugated diene segments thereof of 10 to 20 mol % and (2) the liquid rubber has a number average molecular weight (Mn) of 500 to 5,000 and an average ratio of vinyl bond units of 50 to 70 mol %.

Abstract: A photosensitive constituent for a flexographic printing plate comprising a polyester film as support (B) and a photosensitive elastomer composition (C) and having an adhesive layer (A) therebetween, wherein the photosensitive elastomer composition (C) comprises, as essential components, (a) 50% by weight or more of at least one thermoplastic elastomer comprising the reaction product of a mono-vinyl-substituted aromatic hydrocarbon monomer and a conjugated diene monomer, (b) 5 to 40% by weight of at least one diene-based liquid rubber, (c) 1 to 20% by weight of at least one ethylenically unsaturated compound having 2 unsaturated bonds within its molecule, and (d) 0.1 to 3% by weight of at least one photopolymerization initiator, and wherein (1) the thermoplastic elastomer has an average ratio of vinyl bond units in conjugated diene segments thereof of 10 to 20 mol % and (2) the liquid rubber has a number average molecular weight (Mn) of 500 to 5,000 and an average ratio of vinyl bond units of 50 to 70 mol %.