Abstract:
A method of making a lithographic printing plate includes the steps of: a) providing a lithographic printing plate precursor including (i) a support having a hydrophilic surface or which is provided with a hydrophilic layer, (ii) a coating on the support including a photopolymerizable layer, and, optionally, an intermediate layer between the photopolymerizable layer and the support, wherein the photopolymerizable layer includes a polymerizable compound and a polymerization initiator, b) image-wise exposing the coating in a plate setter, c) optionally, heating the precursor in a pre-heating unit, d) developing the precursor off-press in a gumming unit by treating the coating of the precursor with a gum solution, thereby removing the non-exposed areas of the photopolymerizable layer from the support, wherein the photopolymerizable layer further includes a polymer containing an acid group and a basic nitrogen-containing compound capable of neutralizing the acid group, or wherein the photopolymerizable layer further includes a polymer containing an acid group which is neutralized by a basic nitrogen-containing compound.
Abstract:
A photopolymer printing plate precursor includes a photosensitive coating on a support, wherein the photosensitive coating includes a composition that is photopolymerizable upon absorption of light, and the composition includes at least one binder, a polymerizable compound, a sensitizer, and a photoinitiator. The binder is a copolymer that has a Tg of less than 70° C., and wherein 1 mol-% to 50 mol-% of the monomeric units of the copolymer are substituted by at least one acidic group, has a very high sensitivity and resistance of the exposed image portions against alkaline developers, when exposed with a laser, even if no pre-heat step is performed.
Abstract:
The invention provides a planographic printing plate precursor having at least: a support; and an image recording layer that is provided on the support, the image recording layer comprising: an infrared ray absorbing agent (A); a polymerization initiator (B); a polymerizable compound (C); and a compound (D) represented by the following Formula (I). In Formula (I), at least one of R1 to R3 represents —(CH2CH2O)n—R4, while the remainder of R1 to R3 respectively independently represent a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, or R5—COOH; R4 represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms; n represents an integer of 1 to 20; and R5 represents an alkylene group having 1 to 6 carbon atoms. The invention further provides a printing method using the planographic printing plate precursor and performing on-press development.
Abstract:
A method for preparing a lithographic printing plate includes the steps of—providing a lithographic printing plate precursor including: a support having a hydrophilic surface or which is provided with a hydrophilic layer; and a coating provided on the support and including an image recording layer including hydrophobic thermoplastic polymer particles having an average particle size between about 40 nm and about 63 nm and a hydrophilic binder, the coating further including a pigment present in the image recording layer or in an additional layer of the coating, —image-wise exposing the coating, thereby inducing coalescence of the thermoplastic polymer particles at the exposed areas of the image recording layer; —developing the precursor by applying a gum solution to the coating, thereby removing the non-exposed areas of the image recording layer from the support; and—optionally, baking the developed precursor; wherein the hydrophobic thermoplastic polymer particles have an average particle size between about 40 nm and about 63 nm; the amount of the hydrophobic thermoplastic polymer particles is more than about 70% and less than about 85% by weight, relative to the image recording layers; and the pigment has a hydrophilic surface and provides a visible image after the image-wise exposing and developing with the gum solution. The lithographic printing plate precursor has an improved sensitivity, and the obtained lithographic printing plate exhibits an excellent clean-out, no toning, and a high printing run length.
Abstract:
A lithographic printing plate precursor having a good press life with a practical energy amount, which can be on-press developed without passing through a development processing step after recording an image by a laser of emitting an infrared ray, is provided, which is a lithographic printing plate precursor capable of performing a development and printing by loading on a printing press after imagewise exposure and supplying an oily ink and an aqueous component, the lithographic printing plate precursor comprising a support and an image recording layer, wherein the image recording layer comprises (A) a polymerization initiator, (B) a polymerizable monomer, (C) a binder polymer, and (D) a crosslinked resin particle having a reactive group or (F) a microcapsule containing a polymerizable monomer in the capsule wall, and the image recording layer is imagewise polymerization-curable upon irradiation of actinic ray.
Abstract:
A method of on-press developing a laser sensitive lithographic printing plate with ink and/or fountain solution is described. The printing member comprises on a substrate a photosensitive layer soluble or dispersible in ink and/or fountain solution and capable of hardening upon exposure to a laser. The plate is exposed with a laser and on-press developed with ink and/or fountain solution. The exposure and development are performed with the plate under lightings that contain no or substantially no radiation below a wavelength selected from 400 to 650 nm, or in the dark or substantially dark.
Abstract:
To provide a lithographic printing plate precursor capable of obtaining a plenty of sheets of good printed matters with practical energy dosage, which is excellent in on-press developing property and press life, and capable of reducing pollution of fountain solution, and provide a lithographic printing method. The lithographic printing plate precursor comprises a support having provided thereon an image-recording layer, which lithographic printing plate precursor is mounted on a printing press and imagewise exposed, or mounted on the printing press after imagewise exposure, and then developed by feeding printing ink and/or a fountain solution, wherein at least a part of the unexposed part of the image-recording layer is not dissolved in the printing ink, the fountain solution or both of them, and removed by falling out of film, and the invention provides a lithographic printing method using the same.
Abstract:
An infrared-sensitive planographic printing plate precursor including: a support; a recording layer capable of forming an image through infrared irradiation provided on or above one surface of the support, the recording layer containing a resin, which is water-insoluble and alkali-soluble, and an infrared absorbent; and an organic polymer layer provided on or above the other surface of the support, wherein when the organic polymer layer is formed, a solvent is used, and the total amount of solvent remaining in the organic polymer layer is 10 mg per gram of the organic polymer or less is provided.
Abstract:
The invention provides a planographic printing plate precursor that is writable by laser exposure and is composed of a support, a photosensitive recording layer formed on the support, and a backcoat layer containing an epoxy resin, the backcoat layer being formed on the side of the support opposite to the photosensitive recording layer side; and a stack of the planographic printing plate precursors. According to the invention, scratches on the photosensitive recording side of the planographic printing plate precursor can be prevented when brought into contact with another planographic printing plate precursor in the stack without interleaving slip sheets, and productivity in a plate making process can be improved.
Abstract:
A process for the post-treatment of an imaged lithographic printing plate comprises (a) Contacting a lithographic printing plate having image areas and non-image areas on a lithographic substrate with a solution comprising at least one phosphono-substituted siloxane of the following general formula (I) that is defined herein and (b) drying.