摘要:
A negative-working lithographic printing plate precursor comprises a negative-working radiation-sensitive imageable layer and an outermost layer comprising a vinyl alcohol copolymer comprising at least one unit of each of the (a), (b), and (c) recurring units, in any order, defined in the disclosure. The (c) recurring units are present in the vinyl alcohol copolymer in an amount of at least 0.5 mol %, based on the total recurring units. These precursors can be used to prepare lithographic printing plates either on-press or off-press after imaging using near-UV, visible, or infrared radiation.
摘要:
Negative-working lithographic printing plate precursor a negative-working imageable layer and an outermost water-soluble overcoat layer that is disposed directly on the negative-working imageable layer. The outermost water-soluble overcoat layer comprises: (1) one or more film-forming water-soluble polymeric binders, (2) organic wax particles, and (3) non-wax matte particles. The outermost water-soluble overcoat layer has a dry thickness (t) that is defined by the following equation (I): t=w/r wherein w is the dry coverage of the outermost water-soluble overcoat layer in g/m2, and r is 1 g/cm3. The organic wax particles have an average largest dimension D(wax) that is less than 0.9 of t (in μm), and the non-wax matte particles have an average largest dimension D(matte) that defined by the following equation (II): 1.5 times t≦D(matte)≦40 times t (in μm).
摘要翻译:负性工作平版印刷版前体是负性可成像层和最外层的水溶性外涂层,其直接设置在负性可成像层上。 最外面的水溶性外涂层包括:(1)一种或多种成膜水溶性聚合物粘合剂,(2)有机蜡颗粒和(3)非蜡无光泽颗粒。 最外面的水溶性外涂层具有由下式(I)定义的干燥厚度(t):t = w / r其中w是最外层水溶性外涂层的干覆盖率,单位为g / m 2,以及 r为1g / cm3。 有机蜡颗粒具有小于0.9的t(μm)的平均最大尺寸D(蜡),并且非蜡哑光颗粒具有由下列等式(II)定义的平均最大尺寸D(无光泽度) :1.5倍t≦̸ D(无光泽)≦̸ 40倍t(μm)。
摘要:
A lithographic printing plate precursor comprises an imageable layer comprising a free radically polymerizable component, an initiator composition capable of generating free radicals upon exposure to imaging infrared radiation, an infrared radiation absorbing dye that is defined by Structure (I) shown in the disclosure, which dyes comprise one or more ethylenically unsaturated polymerizable groups in an organic group that is attached to the methine chain. These infrared radiation absorbing dyes exhibit a reduced tendency to crystallize in the imageable layers in the presence of tetraaryl borate counter anions and therefore provide improved shelf life.
摘要:
A method is described for producing an imaged lithographic printing plate, wherein the developer comprises a hydrophilic polymer comprising (m1) structural units derived from at least one compound comprising both a polyalkylene oxide chain and a free radical polymerizable group, and (m2) structural units derived from at least one compound copolymerizable with the free radical polymerizable group of (i) and comprising at least one functional group with pKs
摘要:
Negative-working imageable elements can be imaged and processed to provide lithographic printing plates. These imageable elements are sensitive to infrared radiation but are insensitive to “white” light and thus can be more easily handled under white light conditions. These properties are possible by incorporating a filter dye having a λmax of from about 300 to about 500 nm into the imageable layer of the imageable elements.
摘要:
Negative-working imageable elements are prepared with radiation-sensitive imageable layers that contain surface-modified silica particles such as fumed silica particles and sol-gel silica particles, that are present in an amount of from about 1 to about 40 weight %, have an average particle size of from about 1 to about 500 nm, have surface hydroxy groups, and have a carbon content of from about 0.5 to about 15 weight % that is derived from surface hydrophobic groups having 1 to 30 carbon atoms. The presence of the surface-modified silica particles provides improved abrasion resistance, reduced tackiness, and various other desired properties.
摘要:
Process for the production of a lithographic printing plate, comprising (a) providing a lithographic printing plate precursor comprising (i) a substrate; (ii) a radiation-sensitive coating comprising one or more layers and (iii) optionally an oxygen-impermeable overcoat; (b) image-wise exposing the lithographic printing plate precursor to radiation of a wavelength to which the radiation-sensitive coating is sensitive; (c) optionally subjecting the image-wise exposed precursor to a preheat treatment and/or rinsing with water; (d) removing the non-image areas from the image-wise exposed precursor by means of an alkaline developer solution; (e) optionally subjecting the imaged precursor obtained in step (d) to rinsing with water; (f) treating the imaged lithographic printing plate obtained in step (d) or (e) with a finisher solution; and (g) optionally subjecting the finisher treated plate obtained in step (f) to at least one further process step selected from rinsing with water, drying and baking; characterized in that the finisher solution comprises 0.01 to 15 wt. %, based on the total weight of the finisher, of a hydrophilic polymer comprising: (m1) primary, secondary and/or tertiary amino groups, and (m2) acid groups selected from —COOH, —SO3H, —PO2H2 and PO3H2, and (m3) optionally alkylene oxide units —(CHR1—CH2—O)P—, wherein each R1 independently represents H or —CH3 and p is an integer from 1 to 50.
摘要:
Radiation-sensitive compositions and imageable elements include a polymeric or non-polymeric component in an imageable layer, which component includes 1H-tetrazole groups. The non-polymeric components can be radically polymerizable compounds. The polymeric components can have 1H-tetrazole groups that are pendant to the backbone. The use of such components in negative- or positive-working imageable elements provides high photospeed and improved developability for providing imaged and developed elements, such as lithographic printing plates that show improved chemical resistance and run length.
摘要:
Negative-working imageable elements such as lithographic printing plate precursors, include a free-radically polymerizable component, an initiator composition that is capable of generating free radicals sufficient to initiate polymerization of the free-radically polymerizable component upon exposure to imaging radiation in the presence of a radiation absorbing compound, a radiation absorbing compound, an aerobic free radical inhibitor, optionally a polymeric binder that is not a free radically polymerizable component, and an anaerobic free radical inhibitor. The molar ratio of the anaerobic free radical inhibitor to the aerobic free radical inhibitor is at least 1:1. This combination of inhibitors provides increased shelf life and good latent image stability particularly when the element includes a polymeric topcoat layer that functions as an oxygen barrier.
摘要:
Negative-working imageable elements are prepared with radiation-sensitive imageable layers that contain surface-modified silica particles such as fumed silica particles and sol-gel silica particles, that are present in an amount of from about 1 to about 40 weight %, have an average particle size of from about 1 to about 500 nm, have surface hydroxy groups, and have a carbon content of from about 0.5 to about 15 weight % that is derived from surface hydrophobic groups having 1 to 30 carbon atoms. The presence of the surface-modified silica particles provides improved abrasion resistance, reduced tackiness, and various other desired properties.