Abstract:
A processing method of a lithographic printing plate precursor includes: exposing imagewise a lithographic printing plate precursor comprising a support on a surface of which at least one of: a hydrophilizing treatment; and an undercoat layer has been provided and an image-recording layer, to cure an exposed area of the image-recording layer; and undergoing developing processing with an aqueous solution having pH of from 2 to 10, wherein the aqueous solution comprises an amphoteric surfactant and an anionic surfactant selected from an anionic surfactant having an aliphatic chain and a total number of carbon atoms included in the aliphatic chain of 6 or more and an anionic surfactant having an aromatic ring and a total number of carbon atoms of 12 or more, and a content of the anionic surfactant is from 0.1 to 3.3% by weight of the aqueous solution.
Abstract:
A negative-working imageable element has an imageable layer and a topcoat layer that contains a composition that will change color upon exposure to imaging infrared radiation. The imageable element can be imaged and developed on-press to provide images with improved contrast for print-out.
Abstract:
To provide a method for producing a lithographic printing plate precursor excellent in development property and printing durability, which method restrains mixture of both layers at coating and drying an overcoat layer on an image-recording layer. A method for producing a polymerizable lithographic printing plate precursor including (a) a step of coating a coating solution of an image-recording layer containing (A) a sensitizing dye, (B) a radical polymerization initiator and (C) a radical polymerizable compound on a support, (b) a first drying step of supplying hot air to the image-recording layer, (c) a second drying step of supplying hot air and superheated vapor to the image-recording layer after the first drying step, (d) a step of coating an overcoat layer on the image-recording layer, and (e) a step of drying the overcoat layer.
Abstract:
Lithographic printing plates are prepared by imaging and developing negative-working lithographic printing plate precursors that include certain particulate polymeric binders in the photosensitive imageable layer. Such particulate polymeric binders are poly(urethane-acrylic) hybrids. Development is carried out using a working strength developer that includes one or more organic solvents in a total amount of at least 7 weight % and an anionic surfactant in an amount of at least 5 weight %.
Abstract:
A method of processing an on-press developable lithographic printing plate involving the removal of the overcoat after laser imaging and before on-press development is described. The plate comprises a substrate, an on-press ink and/or fountain solution developable photosensitive layer, and an overcoat. The laser imaged plate is mechanically stripped off the overcoat, and then developed with ink and/or fountain solution on a lithographic press. Such a process allows the use of overcoat to achieve faster photospeed and improved durability of the plate without having various issues as related to overcoat such as contamination to the fountain solution, difficulty to remove of certain overcoat, and limited white light stability.
Abstract:
A lithographic printing plate precursor is provided that, using laser exposure, exhibits an excellent capacity for plate inspection, an excellent on-press development performance or gum development performance, and an excellent scumming behavior, while maintaining a satisfactory printing durability. There is also provided a method of lithographic printing that uses this lithographic printing plate precursor. The lithographic printing plate precursor comprises an image recording layer having (A) a nonionic polymerization initiator that contains at least two cyclic imide structures, and (B) a compound that has at least one addition-polymerizable ethylenically unsaturated bond.
Abstract:
Lithographic printing plates are imaged using an inkjet printer to imagewise apply a chemical or masking agent onto the plate surface. In some embodiments, the chemical causes an affinity change, thereby facilitating lithographic printing.
Abstract:
A heat-sensitive positive-working lithographic printing plate precursor includes a support having a hydrophilic surface or which is provided with a hydrophilic layer, a heat-sensitive coating including an IR absorbing agent, a phenolic resin, and a first polymer, wherein the first polymer is an alkaline soluble polymer including a monomeric unit having a structure according to Formula I or Formula II, wherein at least one of the aromatic groups Ar1 and Ar2 is an optionally substituted heteroaromatic group:
Abstract:
A lithographic printing plate precursor has a substrate and an infrared radiation-sensitive composition comprising a polymeric binder, a free radical polymerizable system consisting of at least one polymerizable component, a compound capable of absorbing infrared radiation, and an initiator system comprising an iodonium salt that is capable of producing free radicals; and at least 1% and up to and including 10% by weight, based on the infrared-sensitive composition, of at least one mono- or polycarboxylic acid having an aromatic moiety.
Abstract:
A method of treating an on-press developable lithographic printing plate with a treating solution after imagewise exposure and before on-press development is described. The plate comprises on a substrate a photosensitive layer developable with ink and/or fountain solution and capable of hardening upon exposure to a radiation. The plate is imagewise exposed with a radiation, overall treated with a treating solution to cause at least one chemical or physical change in the photosensitive layer or on the substrate surface, and then on-press developed with ink and/or fountain solution. Such a treatment allows improvement on the performance of the imagewise exposed plate by, for example, improving the white light stability, forming visible imaging, increasing the hydrophilicity of the substrate, or increasing the developability of the photosensitive layer.