摘要:
A lithographic printing plate precursor can be used to prepare a printing plate using thermal ablation. The precursor has a non-thermally ablatable first layer on a substrate. Over the first layer is a thermally ablatable outer layer that includes an IR absorbing compound in an ablatable polymeric binder. The first layer includes a sol gel as a continuous inorganic matrix and a discontinuous inorganic phase (inorganic particles) dispersed therein.
摘要:
The present invention provides a positive-working, thermally imageable element generally comprising a multi-layered imageable coating. The invention provides an imageable element comprising a substrate, an ink-receptive top layer, and an underlayer, the underlayer including a specific copolymer described herein. The copolymer can be a polymer comprising constitutional units derived from: a) a monomer having a cyclic urea group; b) a monomer comprising an N-substituted maleimide; c) a (meth)acrylamide or (meth)acrylate monomer; and d) a (meth)acrylic acid or vinyl benzoic acid monomer. In another embodiment, the copolymer can be a polymer comprising constitutional units derived from: a) a monomer having a cyclic urea group; b) a (meth)acrylic acid or vinyl benzoic acid monomer; c) and a (meth)acrylonitrile monomer. The imageable element may be used to prepare a lithographic printing plate that is resistant to press chemistry and can optionally be baked to increase press runlength.
摘要:
A coating solution useful in the preparation of printing plate precursors comprises: a) a radiation sensitive composition C comprising a phenolic resin; b) at least one thermoplastic polymer P which has a solubility in aqueous alkaline media ranging from sparingly soluble to insoluble; c) a first solvent component A which is capable of solubilizing both composition C and thermoplastic polymer P; d) a second solvent component B having a volatility less than component A, wherein component B is capable of volatilizing composition C but not thermoplastic polymer P, and composition C and thermoplastic P are homogeneously dissolved in a mixture of components A and B; and e) at least one further polymer AP having a higher molecular weight than the phenolic resin of composition C, wherein polymer AB is miscible with the phenolic resin and immiscible with thermoplastic polymer P. The coating provides a radiation-sensitive layer for the substrate, and the coating contains homogeneously distributed thermoplastic polymer particles.
摘要:
A radiation-sensitive composition, positive-working coating compositions useful for the preparation of lithographic printing plates and lithographic printing plate precursors comprising the composition are disclosed. The composition comprises at least one quinonediazide compound and at least one carboxylic copolymer. The compositions produce lithographic printing plates that show high print run stability.
摘要:
A radiation-sensitive composition for use in printing plates is described. The composition comprises: (a) at least one novolak; (b) at least one naphthoquinone diazide derivative; and (c) a copolymer comprising units A, B, and a unit C comprising a cyclic terminal urea group, wherein unit A is present in an amount of about 5 to about 50 mol % and has the formula is represented by wherein R1 is selected such that the homopolymer of A is alkali-soluble, unit B is present in an amount of about 20 to about 70 mol % and has the following formula is represented by wherein R2 is selected such that the homopolymer of B has a glass transition temperature greater than 100° C., preferably a glass transition temperature in the range from about 100 to about 380° C., and the unit C comprising a cyclic terminal urea group is present in an amount of about 10 to about 50 mol % and has the formula is represented by wherein X is a spacer group which is preferably selected from the group consisting of (a) a —(CR2)m— chain, (b) a —[CH2—CH2—O]m— chain; and (c) a —[Si(R2)—O]m— unit, wherein m is an integer greater than or equal to 1, more preferably between 2 and 12, the spacer group is connected to one of the carbon ring atoms of the cyclic urea unit or to one of the nitrogen atoms of the cyclic urea unit, and n is an integer greater than or equal to 1, more preferably between 1 and 5; and Y is a group selected from the group consisting of: wherein each R in units A, B, and C, the —(CR2)m— chain, the —[Si(R2)—O]m— unit, and group Y represents a bond between the cyclic urea and the spacer group X, or is independently selected from hydrogen, aryl, (C1-C12) alkyl, and or halogen.
摘要:
Single layer IR-sensitive negative-working imageable elements include thermally coalesceable core-shell particles without a polymeric binder in an imageable layer. Thermal imaging causes coalescence of the particles in imaged regions while non-imaged regions can be removed with plain water or an aqueous solution containing an acidic polymer.
摘要:
A radiation-sensitive composition for use in printing plates is described. The composition comprises: (a) at least one novolak; (b) at least one naphthoquinone diazide derivative; and (c) a copolymer comprising units A, B, and a unit C comprising a cyclic terminal urea group, wherein unit A is present in an amount of about 5 to about 50 mol % and has the formula wherein R1 is selected such that the homopolymer of A is alkali-soluble, unit B is present in an amount of about 20 to about 70 mol % and has the following formula wherein R2 is selected such that the homopolymer of B has a glass transition temperature greater than 100° C., preferably a glass transition temperature in the range from about 100 to about 380° C., and the unit C comprising a cyclic terminal urea group is present in an amount of about 10 to about 50 mol % and has the formula wherein X is a spacer group which is preferably selected from the group consisting of (a) a —(CR2)m— chain, (b) a —[CH2—CH2—O]m— chain; and (c) a —[Si(R2)—O]m— unit, wherein m is an integer greater than or equal to 1, more preferably between 2 and 12, the spacer group is connected to one of the carbon ring atoms of the cyclic urea unit or to one of the nitrogen atoms of the cyclic urea unit, and n is an integer greater than or equal to 1, more preferably between 1 and 5; and Y is a group selected from the group consisting of: and wherein each R in units A, B, and C, the —(CR2)m— chain, the —[Si(R2)—O]m— unit, and group Y is independently selected from hydrogen, aryl, (C1-C12) alkyl, and halogen.
摘要:
A singe- or multilayer lithographic printing plate precursor comprises on a substrate a radiation-sensitive coating that comprises a copolymer soluble or dispersible in aqueous alkaline solution and comprising (meth)acryl recurring units, imide recurring units, and amide recurring units derived from corresponding ethylenically unsaturated polymerizable monomers; the copolymer provides increased chemical resistance for the lithographic printing plate precursors which can be negatively or positively working.
摘要:
Copolymers useful in radiation-sensitive layers of printing plates have the units A, B and C wherein unit A is present in an amount of 5 to a maximum of 50 mol % and R1 and R4 are selected such that the homopolymer of A is alkali-soluble, B is present in an amount of 20-70 mol % and R2, R6 and R7 are selected such that the homopolymer of B has a high glass transition temperature, and C is present in an amount of 10-50 mol % and R3 and R5 are selected such that the homopolymer of C is water-soluble and that unit A is different from unit C.
摘要:
Radiation-sensitive compositions comprise at least one novolak, at least one naphthoquinone diazide derivative and a copolymer; the copolymer consisting of the units A, B and C wherein unit A is present in an amount of 5 to a maximum of 50 mol % and R1 and R4 are selected such that the homopolymer of A is alkali-soluble, B is present in an amount of 20 to 70 mol % and R2, R6 and R7 are selected such that the homopolymer of B has a high glass transition temperature, and C is present in an amount of 10 to 50 mol % and R3 and R5 are selected such that the homopolymer of C is water-soluble and that unit A is different from unit C. Furthermore, the invention describes printing plates produced therefrom.