摘要:
Thermally imageable multilayer imageable elements useful as lithographic printing plate precursors that have good solvent resistance are disclosed. The underlayer of the imageable element comprises an acidic copolymer that comprises, in polymerized form, about 10 mol % to about 75 mol % of one or more monomers of the formula: CH2═CH(R1)-Z-X—NH—CO—NH—C6H3—(R2)(CO2H); in which: R1 is H or CH3; R2 is H or OH; Z is —C6H4— or —C(O) —Y—; Y is —O— or —NH—; and X is selected from —C(CH3)2—, —CH(CH3)— and —(CH2)n—, in which n is an integer from 1 to 12.
摘要:
Alkali soluble copolymers, imageable elements useful as lithographic printing plate precursors that contain the alkali soluble copolymers, and methods for forming images using the imageable elements are disclosed. The alkali soluble copolymers comprise, in polymerized form: (a) N-phenylmaleimide, N-cyclohexylmaleimide, N-benzylmaleimide, or a mixture thereof; (b) acrylamide, methacrylamide, or a mixture thereof; (c) acrylonitrile, methacrylonitrile, or a mixture thereof; and (d) one or more monomers selected from the group consisting of monomers of the structure: CH2═C(R)-Z-X—NHC(O)NH—Y—R′, in which: X is —[C(CH3)2]— or —[(CH2)n]—, in which n is 0 to 12; Y is o-, m-, or p-—[C6H4]—; Z is —[C(O)O]—, —[C(O)NH]—, or o-, m-, or p-[—C6H4]—; R is hydrogen or C1 to C4 alkyl; R′ is —OC(O)—OR″, —OC(O)—Ar, or —OSO2—Ar; R″ is C1 to C12 alkyl, C1 to C12 arylalkyl, C1 to C12 aryl, C1 to C12 alkenyl, or trimethylsilyl; Ar is C6H5-n′Tn′, in which Ar has a total of six to ten carbon atoms; each T is independently selected from the group consisting of C1 to C4 alkyl, fluoro, chloro, bromo, iodo, trifluoromethyl, methoxy, and cyano; and n′ is an integer from 0 to 5; and in which the copolymer is soluble in alkaline solutions having a pH greater than at least about 11.
摘要:
Multilayer thermally imageable elements useful as lithographic printing plate precursors are disclosed. The imageable elements comprise a substrate, an underlayer over the substrate, and a top layer over the underlayer. The top layer contains a polymer containing anhydride groups. This polymer is present in the top layer in an amount of at least 60% based on the dry weight of the layer. The imageable elements have excellent resistance to press room chemicals.
摘要:
Multilayer, positive working, thermally imageable, bakeable imageable elements have a substrate, an underlayer, and a top layer. The underlayer comprises a polymeric material that comprises, in polymerized form from about 5 mol % to about 30 mol % of recurring units derived from an ethylenically unsaturated polymerizable monomer having a carboxy group; from about 20 mol % to about 75 mol % of recurring units derived from N-phenylmaleimide, N-cyclohexylmaleimide, N-benzylmaleimide, or a mixture thereof; and from about 3 mol % to about 50 mol % of recurring units derived from a compound represented by the formula: CH2═C(R2)—C(O)—NH—CH2—OR1, in which R1 is C1 to C12 alkyl, phenyl, C1 to C12 substituted phenyl, C1 to C12 aralkyl, or Si(CH3)3; and R2 is hydrogen or methyl. Other materials, such as a resin or resins having activated methylol and/or activated alkylated methylol groups, such as a resole resin, may be present in the underlayer. The elements can be used to produce bakeable lithographic printing plates that are resistant to press chemistries.
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 recording medium comprises an oleophilic substrate and, thereover, a topmost oleophobic layer comprising a cured polymeric silicone matrix that consists essentially of the addition-cure reaction product of a vinyl-functional polydialkylsiloxane and a silane cross-linking agent. The vinyl-functional polydialkylsiloxane has a molecular weight ranging from 30,000 to 75,000 or 110,000 to 130,000. If the molecular weight of the vinyl-functional polydialkylsiloxane is within the range of 30,000 to 75,000, the molar ratio of silane groups to vinyl groups is within the range of about 11:1 to about 25:1; and if the molecular weight of the vinyl-functional polydialkylsiloxane is within the range of 110,000 to 130,000, the molar ratio of silane groups to vinyl groups is from about 5:1 to about 27:1. The recording medium may be used as a lithographic printing plate.
摘要:
Ablation-type printing plates having increased shelf-life are produced using a melamine resin free of water prior to use. A representative production sequence includes providing a substrate having an oleophilic surface; coating, over the substrate, an oleophilic resin composition having (A) a resin phase consisting essentially of a melamine resin substantially free of water and a resole resin, the resole resin being present in an amount ranging from 0% to 28% by weight of dry film, (B) a near-IR absorber dispersed within the resin phase, and (C) a sulfonic acid catalyst dispersed within the resin phase and being present in an amount ranging from 0.7% to 1.6% by weight of dry film; curing the resin composition to produce a dry film; following resin curing, coating an oleophobic polymer composition over the cured resin composition; and curing the oleophobic polymer composition.
摘要:
In ablation-type printing plates involving silicone acrylate top layers, curing at high oxygen levels not only substantially reduces or eliminates toning, but does not adversely affect plate durability or printing performance.
摘要:
Gum solutions are formulated to protect a negative-working photopolymer imaging layer coated on an anodized aluminum substrate that has undergone a post-anodic sealing treatment with inorganic phosphate and inorganic fluoride, followed by development. In various embodiments, the developer and gum solution have different compositions but contain at least one polycarboxylic acid—which may be a polymer—that beneficially desensitizes the surface after the unexposed photopolymer layer is removed.
摘要:
Negative-working imagable elements can be imaged and then developed using a lower pH organic-based single-phase developer that is less toxic and corrosive and that can be more readily disposed of after use. This developer has a pH less than 12 and comprises a) an amphoteric surfactant comprising a nitrogen-containing heterocycle, b) an amphoteric surfactant having two or more nitrogen atoms, or c) an amphoteric surfactant of a) and an amphoteric surfactant of b).