Fuji Photo Film Company, Limited

National Patent Development Corporation

Tomoegawa Paper Co., Inc.

Nobuyuki Kita

Tatsuji Higashi

Hiroshi Matsumoto

Masanori Imai

Mitsuru Koike

Yoshihiko Urabe

Hitoshi Hagiwara

Hidekazu Oohashi

Keiji Akiyama

Hiroshi Misu

Toshiyuki Sekiya

Toshio Uchida

Shigeo Koizumi

Akinobu Koike

Eiji Nakakita

Yasuhisa Narutomi

Kei Okuno

Hiroshi Takahashi

Keisuke Shiba

Sadao Osawa

Kazuo Maemoto

Tadao Toyama

Hisashi Hotta

Hisao Ohba

Akira Nagashima

Noriaki Watanabe

Azusa Ohashi

Susumu Yoshida

Mitsumasa Tsuchiya

Yukio Abe

Sadaharu Ikeda

Shigeru Sato

Masato Iwai

Masao Tanaka

Hiroaki Suzuki

Nobuo Nishikawa

Kazuyoshi Takii

A heat-sensitive lithographic printing plate precursor comprising a substrate having ink-receptive surface or coated with an ink-receptive layer having provided thereon a hydrophilic layer which comprises:

Heat-sensitive lithographic printing plate precursor

A process for producing a lithographic printing plate by on-press developing a heat-sensitive lithographic printing plate precursor having on a metallic base in this order (1) an ink-receptive layer, (2) a hydrophilic layer containing colloidal particles of an oxide or hydroxide of at least one element, e.g., silicon or aluminum, and (3) a hydrophilic overcoat layer capable of being removed on a printing machine, which includes: rotating a plate cylinder having attached thereto the heat-sensitive lithographic printing plate precursor which has been exposed; subsequently supplying an ink and a dampening water to the plate surface by simultaneously bringing a dampening roll and an inking roll into contact with the plate surface or by bringing a water-metering roll into contact with an inking roll and then bringing the inking roll, which functions also to dampen, into contact with the plate surface; and thereby removing the overcoat layer and the exposed parts of the hydrophilic layer.

Processes for producing lithographic printing plate

A heat-sensitive lithographic printing plate precursor having on a support (1) an ink-receptive layer comprising an oleophilic organic high molecular compound and (2) a water-receptive layer easily allowing removal by a fountain solution or a printing ink when heated, which are arranged in this order; with the water-receptive layer being a layer formed using a coating solution comprising a solvent capable of dissolving the organic high molecular compound of the ink-receptive layer in a proportion of 1 to 40 weight % of the total solvents in the coating solution.

Negative-working heat-sensitive lithographic printing plate precursor

A heat-sensitive lithographic printing plate precursor is disclosed, comprising a metal substrate having thereon 1) an ink-receptive layer, 2) a water-receptive layer comprising a colloidal particulate oxide or hydroxide of at least one element selected from the group consisting of beryllium, magnesium, aluminum, silicon, titanium, boron, germanium, tin, zirconium, iron, vanadium, antimony and transition metals, or additionally 3) a water-soluble overcoat layer, at least one layer of the ink-receptive layer, the water-receptive layer and the overcoat layer containing a compound capable of converting light into heat and the ink-receptive layer containing an epoxy resin having a softening point of 120&deg; C. or more.

A heat-sensitive lithographic printing plate precursor, comprising a support having a hydrophilic surface on which (1) a thermal polymerization layer comprising an aqueous alkali-soluble polymer having addition polymerizable unsaturated bonds at its side chains and a thermal polymerization initiator and (2) a water-soluble overcoat layer comprising a water-soluble polymer and a compound capable of converting light into heat are provided in this order.

A heat-sensitive lithographic printing plate precursor is disclosed, which comprises an aluminum support having provided thereon an ink-receptive layer and a hydrophilic layer containing a colloidal particle oxide or hydroxide of at least one element selected from the group consisting of beryllium, magnesium, aluminum, silicon, titanium, boron, germanium, tin, zirconium, iron, vanadium, antimony and transition metals, wherein at least one layer of the ink-receptive layer and the hydrophilic layer contains a compound capable of converting light into heat, the aluminum support has an anodic oxide film in an amount of 2 g/m or more, and the anodic oxide film has been subjected to sealing treatment at a sealing rate of 50% or more.

A heat-sensitive precursor of lithographic printing plates, which comprises a hydrophilic layer provided on a substrate having an ink-receptive surface or coated with an ink-receptive layer; the printing plate precursor further having a water-soluble overcoat layer on the hydrophilic layer, and the hydrophilic layer being a three-dimensionally cross-linked hydrophilic layer, the heated area of that is easily removed by a fountain solution or ink when subjected to printing operations.

A presensitized plate for use in making a lithographic printing plate comprises a substrate; a photosensitive layer and a mat layer whose projections have an average diameter of not more than 100 .mu.m, an average height of not more than 10 .mu.m and whose coated amount ranges from 5 to 200 mg/m.sup.2, the photosensitive layer and the mat layer being applied onto the upper surface of the substrate; and a coating layer of an organic polymeric compound having a glass transition point of not less than 20.degree. C. and a thickness ranging from 0.01 to 8.0 .mu.m, the coating layer being applied onto the back face of the substrate. The presensitized plate makes it possible to solve the problem of the formation of scratches and the adhesion of the photosensitive layer to the back face of the PS plate even when a large number of PS plates are transported and/or stored while putting them in piles without sandwiching the PS plate between interleaves. The coated layer applied to the back face of the PS plate is tough and shows good adhesion to the substrate and is not peeled off during handling, development processing and printing operations.

Presensitized plate for use in making lithographic printing plate

A dry PS plate comprises a substrate having provided thereon in order a primer layer, a light-sensitive layer and a silicone rubber layer wherein the primer layer comprises a film forming polyurethane resin and a diazonium salt polycondensate. The dry PS plate is excellent in the adhesion strength between the substrate and the light-sensitive layer. The adhesion is surely maintained even after imagewise exposure to light and the subsequent development. The dry PS plate shows excellent image reproduction and the resulting dry lithographic plate is excellent in printing durability as well as resistance to scratch.

PS plate for use in making lithographic printing plate requiring no

A developer for a presensitized plate for use in making a lithographic printing plate requiring no dampening water comprises: (1) 1 to 39% by weight of at least one alcohol derivative selected from the group consisting of those represented by the following general formula (I): ##STR1## (wherein R.sup.1 represents an alkyl or alkenyl group having 4 to 12 carbon atoms; R.sup.2 represents a hydrogen atom or a methyl group; and n is an integer ranging from 1 to 6); (2) 1 to 39% by weight of at least one water-soluble organic solvent having a boiling point of not less than 100.degree. C.; and (3) 60 to 98% by weight of water. If this developer is used, foaming is hardly caused during the development processing a PS plate requiring no dampening water, it has excellent developing ability and half tone dot reproduction and can provide an excellent lithographic printing plate free of defects such as scratch marks.

Developer for PS plate requiring no dampening water

The present invention relates to a presensitized plate for use in making a lithographic plate requiring no dampening water and comprising, on a support, a light-sensitive resin layer and a silicone rubber layer, in this order, wherein the silicone rubber layer is crosslinked by addition reaction of an .fwdarw.SiH group with a --CH.dbd.CH-- group and wherein the light-sensitive resin layer comprises: (1) a monomer or oligomer having at least one photopolymerizable or photo-crosslinkable and olefinically unsaturated double bond, (2) an organic solvent-soluble polyurethane resin having a glass transition temperature of 20.degree. C. or below and being capable of forming a film, and (3) a photopolymerization initiator. According to the present invention, the PS plate has excellent image-forming properties and printing properties.

A light-sensitive composition which comprises, (a) an ethylenically unsaturated addition polymerizable compound, (b) an alkaline water-soluble or swellable, and film-forming polymer, (c) a photopolymerization initiator, (d) a negative working diazo resin, and (e) at least one compound selected from the group consisting of a higher fatty acid and a higher fatty acid amide which are solid at ordinary temperatures. The light-sensitive composition is hardly influenced by oxygen and is suitable for a presensitized plate from which a printing plate is to be prepared.

Light-sensitive diazo resin composition containing a higher fatty acid

A presensitized plate for use in making a lithographic printing plate requiring no dampening water comprises a substrate provided thereon with in order: (1) a photopolymerizable light-sensitive layer which comprises a monomer or an oligomer having at least one photopolymerizable olefinically unsaturated double bond, an organic solvent-soluble polyurethane resin or polyamide resin which is solid at room temperature and has film-forming ability and a photopolymerization initiator; (2) a crosslinked silicone rubber layer; and (3) a transparent cover coat layer, wherein the photopolymerization initiator comprises dialkylaminoarylcarbonyl compounds and at least one member selected from the group consisting of xanthones, thioxanthones, acrydones, benzophenones which do not carry a dialkylamino group, benzanthrones and anthraquinones and the transparent cover coat layer is formed from a biaxially oriented polypropylene film having a thickness ranging from 6 to 22 .mu.m and an oxygen permeability ranging from 900 to 10,000 cc/m.sup.2 /24 hr./at. at 20.degree. C. The presensitized plate does not cause so-called 'fogging' even when it is kept to stand under irradiation with white light rays and whose sensitivity is not adversely affected by the degree of vacuum when the plate is exposed to light with a vacuum contact printer.

PS plate for making lithographic printing plate requiring no dampening

A presensitized plate, for use in making a lithographic printing plate requiring no dampening water, comprises a substrate, a light-sensitive resin layer applied thereon and a silicone rubber layer formed on the light-sensitive layer which is cross-linked through a reaction of SiH groups with --CH.dbd.CH-- groups, the light-sensitive resin layer comprising:

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Shizuoka, Japan

Nobuyuki Kita