Abstract:
The present invention relates to a negative photosensitive composition comprising: (A) an infrared absorber, (B) an organic boron compound which has a function as a polymerization initiator when used in combination with the infrared absorber (A), (C) an onium salt, and (D) a compound having a polymerizable unsaturated group. The use of the negative photosensitive composition of the present invention makes it possible to provide a negative photosensitive composition which is curable by infrared light and is less likely to cause polymerization inhibition due to oxygen during radical polymerization, and is also excellent in storage stability, and to provide a negative photosensitive lithographic printing plate which can directly form images by irradiation with infrared light from a solid laser or a semiconductor laser based on digital signals without preheating and shows high sensitivity, and is also excellent in printing durability and storage stability.
Abstract:
The invention provides a negative image recording material comprising: a support and an image recording layer disposed on the support, the image recording layer comprising an amide-acid compound containing a carboxyl group and an amide group expressed by the following General Formula (1): wherein L11 represents a hydrogen atom or a hydrocarbon group having 30 or fewer carbon atoms which may have a substituent; and wherein the amide-acid compound is insolubilized by a thermal ring-closure reaction between the carboxyl group and the amide group. The invention further provides a negative image recording material comprising a support, an image recording layer disposed on the support, the image recording layer containing a polymerization initiator and a polymerizable compound, and an overcoat layer disposed on the image recording layer, the overcoat layer containing the amide-acid compound expressed by the General Formula (1).
Abstract:
A method of on-press developing a high-speed 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 on-press development is performed with the plate under a yellow-red light or in substantial darkness, and the lithographic printing is performed under white light.
Abstract:
Disclosed is a printing plate material comprising a surface roughened aluminum support, and provided thereon, an image formation layer containing a heat-curable polymer having a main chain polymer in the main chain, and an acryloyl group or a methacryloyl group in the side chain, a glass transition temperature Tg of the main chain polymer being from 0 to 100° C., wherein the printing plate material is capable of being developed on a printing press.
Abstract:
An on-press ink and/or fountain solution developable lithographic printing plate comprising a photosensitive layer over an electrochemically grained, anodized, hydrophilically treated aluminum substrate with a reflection optical density of at least 0.30 is disclosed. The photosensitive layer is soluble or dispersible in ink and/or fountain solution and capable of hardening upon exposure to a laser having a wavelength of from 200 to 1200 nm. The plate is exposed with the laser off press or on press, and then on-press developed with ink and/or fountain solution. Such darker aluminum substrate in combination with the hydrophilic treatment allows fast press roll up, clean background, and good printing durability of the plate.
Abstract:
A method for making a heat-sensitive negative-working lithographic printing plate precursor is disclosed comprising the steps of (i) preparing a coating solution comprising hydrophobic thermoplastic polymer particles and a hydrophilic binder; (ii) applying said coating solution on a support having a hydrophilic surface or which is provided with a hydrophilic layer, thereby obtaining an image-recording layer; (iii) drying said image-recording layer; characterized in that said hydrophobic thermoplastic polymer particles have an average particle size in the range from 45 nm to 63 nm, and that the amount of said hydrophobic thermoplastic polymer particles in the image-recording layer is at least 70% by weight relative to the dried image-recording layer.
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:
The present invention provides a photosensitive resin composition which can provide a printing plate material having superior image remaining property and printing durability, which can be subjected to alkaline development. The present invention relates to a photosensitive resin composition comprising an ethylenically unsaturated compound, an alkali-soluble resin, a near-infrared-absorbing dye, a halomethyl group-containing compound and an organo boron anion-containing compound, wherein said alkali-soluble resin has carboxyl groups as a side chain, at least one of which is reacted with an epoxy group-containing ethylenically unsaturated compound to introduce an ethylenically unsaturated group, said organo boron anion-containing compound is a compound represented by a certain chemical formula (a), and wherein weight ratio of said ethylenically unsaturated compound: said alkali-soluble resin is from 40:60 to 90:10.
Abstract:
A method of preparing negative-working, single-layer imageable elements improves their storage stability in a humid environment. The method includes enclosing the coated imageable elements in a water-impermeable sheet material that substantially inhibits the transfer of moisture to and from the imageable element. Such imageable elements include a radiation-sensitive composition that includes a radically polymerizable component, an initiator composition to provide radicals upon exposure to imaging radiation, a radiation absorbing compound, and a polymeric binder having poly(alkylene glycol) side chains.
Abstract:
Disclosed is an image forming method possessing the steps of producing a planographic printing plate via a development treatment of exposing a hydrophilic surface of an aluminum support by removing a thermosensitive image formation layer provided on the hydrophilic surface, that is not imagewise heated on a printing press, after imagewise heating a planographic printing plate material having the thermosensitive image formation layer provided on the hydrophilic surface of the aluminum support, and of treating the planographic printing plate with an ink cleaning agent after printing, wherein the hydrophilic surface is colored by a colorant having a solubility of 5-100 g, based on 1 liter of n-decane, and the colorant on the hydrophilic surface exposed after removing the thermosensitive image formation layer is removed in the above step of treating the planographic printing plate with an ink cleaning agent.