Abstract:
A planographic printing plate precursor including: a support; and an image recording layer which is disposed on the support and contains a binder polymer, a polymerization initiator, a polymerizable compound, and an IR absorber. Upon exposure with a laser beam, an exposed portion of the image recording layer in the vicinity of the surface of the image recording layer is cured, and an exposed portion of the image recording layer in the vicinity of an interface between the image recording layer and the support is not cured. A developing rate of an unexposed portion of the image recording layer by an alkaline developer having a pH of 10 to 13.5 is preferably 100 nm/sec or more, and a permeation rate of the alkaline developer to an exposed portion of the image recording layer is preferably 100 nF/sec or less.
Abstract:
There is provided a lithographic printing plate precursor having good on-machine development quality, and moreover high sensitivity and high printing durability, which comprises a support having provided thereon an image forming layer containing (1) at least one ingredient selected from the group consisting of fine particles containing a compound having two or more vinyloxy groups and microcapsules encapsulating a compound having two or more vinyloxy groups, (2) a light-to-heat conversion agent, (3) a hydrophilic resin and (4) an acid precursor, wherein the acid precursor is not contained in the fine particles or the microcapsules.
Abstract:
A presensitized lithographic plate comprises a support and a hydrophilic image-recording layer. The hydrophilic image-recording layer contains a hydrophilic polymer and an agent capable of converting hydrophilic to hydrophobic when the agent is heated. The hydrophilic polymer comprises a main chain and branched chains. Each of the branched chain comprises a hydrophilic chain having a molecular weight in the range of 200 to 1,000,000. A hydrophilic substrate and a lithographic printing process are also disclosed.
Abstract:
The present invention provides a planographic printing plate precursor having a support, a photosensitive layer and a protective layer. The photosensitive layer contains at least an infrared absorbing agent, a polymerization initiating agent, a polymerizable compound and a binder polymer having repeating units represented by the following Formula (i). Further, the protective layer contains at least an inorganic lamellar compound. In Formula (i), R1 represents a hydrogen atom or a methyl group; R2 represents a connecting group having two or more types of atom selected from the group consisting of a carbon atom, a hydrogen atom, an oxygen atom, a nitrogen atom, and a sulfur atom and having 2 to 82 atoms in total; A represents an oxygen atom or —NR3—, and R3 represents a hydrogen atom or a monovalent hydrocarbon group having 1 to 10 carbon atoms; and n is an integer of 1 to 5.
Abstract:
A planographic printing plate precursor comprising an aluminum support having a hydrophilic front surface, and a negative recording layer provided on the front surface, wherein the negative recording layer includes a polymerizable compound, a radiation absorber, and a compound that generates a radical upon application of radiation or heat, and a Bekk smoothness of a back surface of the planographic printing plate precursor is 1000 seconds or less. Also provided are a stack of the planographic printing plate precursors and a method of making a planographic printing plate using the planographic printing plate precursor.
Abstract:
A method of manufacturing a light sensitive planographic printing plate which has an image forming layer containing (A) a coloring material having an absorption in a wavelength range of 700 nm through 1200 nm and (B) a radical generator on a support and is exposed by a laser beam with a light emission wavelength in a wavelength range of 700 nm through 1200 nm, the method comprising: at least coating process, dry process, cutting process, and inspection/sorting process, wherein either of the coating process, the dry process, the cutting process, or the inspection/sorting process is carried out under light of a light source comprising a light-emitting diode with an emission wavelength maximum in a range of 400 nm through 500 nm and a fluorescent phosphor to emit an yellow light by absorbing a light emission of the light-emitting diode.
Abstract:
A planographic printing plate precursor according to the invention includes: a support; and a recording layer disposed on the support and containing an alkali-soluble polymer compound and an infrared absorber, wherein a contact angle at a surface of the planographic printing plate precursor is 70° or less in a case of oil in water and 140° or more in a case of water in oil. Examples of a method for achieving such surface physical properties include inclusion, in a recording layer, of a polymer having a lipophilic functional group on a side chain thereof. According to the invention, a planographic printing plate precursor for direct print making can be obtained, which precursor improves the image forming property of the recording layer using an alkali-soluble polymer compound, is excellent in the lipophilicity of an image portion and the removing property of a non-image portion, and produces printed matters of high quality with excellent reproducibility even in the image formation with an FM screen or high number of output lines.
Abstract:
An object of the invention is to provide a planographic printing plate material exhibiting excellent dot reproduction and printing durability and a support for the planographic printing plate material. Disclosed is a support for a planographic printing plate material having a surface roughened via electrolytic surface-roughening treatment and anodization treatment conducted to one surface of an aluminum plate, wherein a) average surface roughness (Ra) of the roughened surface is 0.30-0.55 μm, and b) the roughened surface possesses a surface profile in which a ratio of Xa/Xb is 0.40-0.70, where Xa is the width expanding to the shallow region side and Xb is the width expanding to the deep region side at the position reaching peak depth in amplitude frequency.
Abstract:
A lithographic printing plate precursor comprising a support and an image-recording layer containing at least one compound selected from the group consisting of a spiropyran compound and a spirooxazine compound, and an acid generator, and a lithographic printing method including a process of removing the unexposed area of the image-recording layer on a printing press.
Abstract:
A method for making a lithographic printing plate is disclosed which comprises the steps of: (i) providing a negative-working, heat-sensitive lithographic printing plate precursor comprising a support having a hydrophilic surface or which is provided with a hydrophilic layer and a coating provided thereon, the coating comprising an image-recording layer which comprises hydrophobic thermoplastic polymer particles and a hydrophilic binder, wherein the hydrophobic thermoplastic polymer particles have an average particle size in the range from 45 nm to 63 nm and wherein the amount of the hydrophobic thermoplastic polymer particles in the image-recording layer is at least 70% by weight relative to the image-recording layer; (ii) exposing the coating to heat or infrared light, thereby inducing coalescence of the thermoplastic polymer particles at exposed areas of the coating; (iii) developing the precursor by applying an aqueous, alkaline solution, thereby removing non-exposed areas of the coating from the support, wherein the aqueous alkaline solution has a pH≧11 and comprises a phosphate buffer or a silicate buffer.