Fluid photo-crosslinkable compositions for the manufacture of relief printing plates

Claim 2

A fluid, photo-crosslinkable composition for use in the manufacture of a laminate and comprising a photoinitiator and a mixture of the following materials in the following proportions: A. from 40 to 80 percent by weight of a soluble, olefinically unsaturated isocyanate group-free polyurethane which has a molecular weight of from 400 to 10,000, and which has been manufactured by reaction of A1. one or more soluble olefinically saturated polyesters having a hydroxyl number of from 100 to 300 and derived from a saturated polyhydric aliphatic alcohol of 2 to 8 carbon atoms and a saturated dicarboxylic acid of 4 to 8 carbon atoms or from a mixture thereof containing corresponding unsaturated alcohol and/or acid components in an amount such that the mixture contains at least 50 mole percent saturated aliphatic compounds with (A2) a polyisocyanate of 6 to 36 carbon atoms and (A3) a monoacrylate and/or monomethacrylate of an aliphatic diol of 2 to 10 carbon atoms, and B. from 20 to 60 percent by weight of at least one photopolymerizable C 6 to C 8 N-vinyllactam monomer or a mixture of at least 20% by weight thereof with at least one other photopolymerizable monomer.

Claim 3

A composition as claimed in claim 1 wherein the unsaturated polyurethane (A) is one which has a molecular weight of from 1000 to 5000.

Claim 4

A composition as claimed in claim 1 wherein the unsaturated polyurethane (A) is one which has been manufactured from a polyester (A1) having a molecular weight of from 500 to 3000.

Claim 5

A composition as claimed in claim 1 wherein the unsaturated polyurethane (A) is one which has been manufactured from a soluble olefinically saturated polyester (A1) having a molecular weight of from 500 to 5,000 and obtained from a polyhydric alcohol and either adipic acid or a mixture thereof with phthalic acid or phthalic anhydride.

Claim 6

A composition as claimed in claim 1 wherein the N-vinyl lactam is N-vinyl-pyrrolidone.

Claim 7

A composition as claimed in claim 1 wherin the monomer mixture contains more than 50% by weight of one or more C 6 to C 8 N-vinyllactams.

Claim 8

A relief printing plate obtained from a laminate comprising a substrate and a layer of a photo-crosslinkable composition consisting essentially of a photoinitiator and a mixture of the following materials in the following proportions: A. from 40 to 80 percent by weight of a soluble, olefinically unsaturated isocyanate group-free polyurethane which has a molecular weight of from 400 to 10,000, and which has been manufactured by reaction of A1. one or more soluble olefinically saturated polyesters having a hydroxyl number of from 100 to 300 and derived from a saturated polyhydric aliphatic alcohol of 2 to 8 carbon atoms and a saturated dicarboxylic acid of 4 to 8 carbon atoms or from a mixture thereof containing corresponding unsaturated alcohol and/or acid components in an amount such that the mixture contains at least 50 mole percent saturated aliphatic compounds with (A2) a polyisocyanate of 6 to 36 carbon atoms and (A3) a monoacrylate and/or monomethyacrylate of an aliphatic diol of 2 to 10 carbon atoms, and B. from 20 to 60 percent by weight of at least one photopolymerizable C 6 to C 8 N-vinyllactam monomer or a mixture of at least 20% by weight thereof with at least one other photopolymerizable monomer, by image-wise exposure of said layer to actinic light and thereafter effecting removal of the material from the unexposed areas of said layer.

Claim 9

A relief printing plate obtained from a laminate comprising a substrate and a layer of a photo-crosslinkable composition consisting essentially of a photoinitiator and a mixture of the following materials in the following proportions: A. from 40 to 80 percent by weight of a soluble, olefinically unsaturated isocyanate group-free polyurethane which has a molecular weight of from 400 to 10,000, and which has been manufactured by reaction of A1. one or more soluble olefinically saturated polyesters having a hydroxyl number of from 100 to 300 and derived from a saturated polyhydric aliphatic alcohol of 2 to 8 carbon atoms and a saturated dicarboxylic acid of 4 to 8 carbon atoms or from a mixture thereof containing corresponding unsaturated alcohol and/or acid components in an amount such that the mixture contains at least 50 mole percent saturated aliphatic compounds with (A2) a polyisocyanate of 6 to 36 carbon atoms and (A3) a monoacrylate and/or monomethyacrylate of an aliphatic diol of 2 to 10 carbon atoms, and B. from 20 to 60 percent by weight of at least one photopolymerizable C 6 to C 8 N-vinyllactam monomer or a mixture of at least 20% by weight thereof with at least one other photopolymerizable monomer, by image-wise exposure of said layer to actinic light and thereafter effecting removal of the material from the unexposed areas of said layer.

Claim 10

A process for the production of relief printing plates by image-wise exposing to actinic light the photocrosslinkable layer of a laminate comprising a substrate and a photo-crosslinkable layer of a composition consisting essentially of a photoinitiator and a mixture of the following materials in the following proportions: A. from 40 to 80 percent by weight of a soluble, olefinically unsaturated isocyanate group-free polyurethane which has a molecular weight of from 400 to 10,000, and which has been manufactured by reaction of A1. one or more soluble olefinically saturated polyesters having a hydroxyl number of from 100 to 300 and derived from a saturated polyhydric aliphatic alcohol of 2 to 8 carbon atoms and a saturated dicarboxylic acid of 4 to 8 carbon atoms or from a mixture thereof containing corresponding unsaturated alcohol and/or acid components in an amount such that the mixture contains at least 50 mole percent saturated aliphatic compounds with (A2) a polyisocyanate of 6 to 36 carbon atoms and (A3) a monoacrylate and/or monomethyacrylate of an aliphatic diol of 2 to 10 carbon atoms, and B. from 20 to 60 percent by weight of at least one photopolymerizable C 6 to C 8 N-vinyllactam monomer or a mixture of at least 20% by weight thereof with at least one other photopolymerizable monomer, and thereafter removing the material from the unexposed areas of said layer.

Claim 11

A process for the production of relief printing plates by image-wise exposing to actinic light the photocrosslinkable layer of a laminate comprising a substrate and a photo-crosslinkable layer of a composition consisting essentially of a photoinitiator and a mixture of the following materials in the following proportions: A. from 40 to 80 percent by weight of a soluble, olefinically unsaturated isocyanate group-free polyurethane which has a molecular weight of from 400 to 10,000, and which has been manufactured by reaction of A1. one or more soluble olefinically saturated polyesters having a hydroxyl number of from 100 to 300 and derived from a saturated polyhydric aliphatic alcohol of 2 to 8 carbon atoms and a saturated dicarboxylic acid of 4 to 8 carbon atoms or from a mixture thereof containing corresponding unsaturated alcohol and/or acid components in an amount such that the mixture contains at least 50 mole percent saturated aliphatic compounds with (A2) a polyisocyanate of 6 to 36 carbon atoms and (A3) a monoacrylate and/or monomethyacrylate of an aliphatic diol of 2 to 10 carbon atoms, and B. from 20 to 60 percent by weight of at least one photopolymerizable C 6 to C 8 N-vinyllactam monomer or a mixture of at least 20% by weight thereof with at least one other photopolymerizable monomer, and thereafter removing the material from the unexposed areas of said layer.