Dainippon Ink and Chemicals, Incorporated

Kodak Polychrome Graphics, Gmbh

Other

Eastman-kodak Company

Dianippon Ink and Chemicals, Inc.

Yasuhiko Kojima

Yasuo Shigemitsu

Naoki Obi

Kiyoshi Suematsu

Koji Oe

Shinji Shimizu

Yasuyuki Watanabe

Naohito Saito

Haruhiko Kaji

Hiroaki Muratake

Nansei Tasiro

Jun Takeuchi

Eiji Hayakawa

Katsuji Takahashi

Tadao Shoji

Maru Aburano

Nansei Tashiro

Yasuhiro Ishizuka

Shoichi Hotate

Masatoshi Katayama

Yonosuke Tsuka

To provide a lithographic printing plate precursor which generates no stains in the non-image area and is also excellent in development latitude. Disclosed is a lithographic printing plate precursor comprising a support and a photosensitive layer, said lithographic printing plate precursor further comprising a subbing layer containing a maleamic acid (co)polymer, in which at least one hydrogen atom on a nitrogen atom is substituted with an onium group, provided between the photosensitive layer and the support.

Lithographic printing plate precursor

Photosensitive compositions comprising a phenol resin having a urea bond in the main chain, planographic printing plate precursors containing the photosensitive compositions, and methods for preparing planographic printing plates using the planographic printing plate precursors are disclosed. Planographic printing plates that exhibit good durability, good exposure visual image property, and good solvent resistance; particularly superior resistance to washing oil used in UV ink printing; and superior baking property are produced.

Photosensitive composition comprising a phenol resin having a urea bond in the main chain

Lithographic printing form precursors comprising positive working polymeric coatings on substrates may during storage or transportation undergo undesirable changes in their imaging properties. It has been found that acceptable properties can be restored by carrying out a heat treatment which involves a relatively short heating stage followed by accelerated cooling.

Printing form precursors

The present invention relates to a lithographic printing plate in which images can be inscribed by laser beams, and which has high resolving power, high sensitivity, and the improved reservation stability, and relates to its image-producing method, and a photosenstitive composition which can preferably be used as an original plate for lithographic printing. The photosenstitive composition includes an aqueous resin composition including fine particles (a) of a resin having at least one neutralized anionic group and having a heat fusion property, and a water soluble resin (b) having at least one neutralized anionic group, wherein the water soluble resin (b) is included in a range of 1 to 30% by weight, relative to the total weight of the aqueous resin composition; and a substance (c) which absorbs light and generates heat.

Photosensitive composition, original plate using the same for lithographic printing, and method for producing images on original plate

In order to provide a computer-to-plate (CTP) plate in which an image can be inscribed by a laser beam having Ithe maximum strength in a near infrared or infrared region, and heat processing is not necessary prior to developing a latent image, and which allows the use of a conventional printing apparatus as it is upon printing, (I) a lithographic printing plate is provided which has on a substrate, a photosensitive layer comprising a photosensitive composition containing a crosslinking agent, an aqueous dispersion of resin fine particles made of a resin which is self water-dispersible having a carboxylic group and a functional group capable of performing cross-linking reactions with the crosslinking agent, and an infrared absorption agent; and (II) an image forming method is provided which is characterized in that after an image has been formed on a photosensitive layer of the lithographic printing plate set forth in the above (I) by using a laser beam, the image is subjected to wet development.

Lithographic printing plate and image forming method

A heat-sensitive composition is disclosed which includes a substance which absorbs light and generates heat, an anionic self water-dispersible resin particle having an acid value of 10 to 300 and an average particle diameter of 0.005 to 15 &mgr;m, and a fluorine base surfactant. An original plate for a lithographic printing plate is disclosed which includes an ordinary negative- or positive-type PS plate having coated thereon the heat-sensitive composition. The original plate is image-wise exposed with high energy density light based on digital image information from a computer, subjected to first development with an aqueous alkali solution, flood exposure with active light, a second development with a developer for a negative or a positive, and post-treatment to obtain a printing plate.

Heat sensitive composition, original plate using the same for lithographic printing plate, and process for preparing printing plate

The present invention relates to a planographic printing plate employed in the field of offset printing, and more particularly, to a preparation method for a printing plate employing a conventional planographic printing original plate with a novel light source. In this method, an image is formed to a planographic printing original plate, in which at least one photosensitive layer sensitive in the region of 300 nm&tilde;450 nm is provided on a substrate, by scan irradiating the plate with high density energy light in the form of the image, and then performing wet development and a post-treatment. This preparation method for the printing plate is characterized in that the output wavelength of the high density energy light is within the range of 300 nm or more, but less than 370 nm, and the high density energy light is high density energy light of the second or third harmonic obtained from a solid-state semiconductor or a solid-state exited by semiconductor. By means of this method, it is possible for an image to be directly drawn stably and at low cost to a conventional planographic printing original plate that was manufactured for an application with active rays, by employing high density energy light that is scan irradiated according to digital information. As a result, high resolution images can be reproduced easily.

Preparation method for printing plate

An image-forming process developing a previously image-exposed silver halide photographic material with an alkaline developer containing a reductone compound as a main developing agent in the presence of a 1,2,5-thiadiazole compound and/or a 2,1,3-benzothiadiazole compound, and the silver halide photographic material and the photographic developer being used for the process are disclosed. In this case, the 1,2,5-thuiadiazole compound and/or the 2,1,3-benzothiadiazole may be contained in the silver halide photographic material and/or the alkaline developer. Super high-contrast images for photomechanical process having a gamma of higher than 15 and having no pepper and less fog can be obtained.

Process of forming super high-contrast negative images and silver halide

A process of forming a super high-contrast negative image is disclosed, which comprises the steps of imagewise exposing a negative-working silver halide photographic material comprising a support having thereon one or more hydrophilic colloidal layers, at least one of the one or more hydrophilic colloidal layers being a negative-working silver halide emulsion layer, and then developing the photographic material with a developer containing an aminophenol derivative developing agent and a reductone compound in the existence of an organic compound having a negative reduction potential. A negative-working silver halide photographic material and a photographic developer being used for the image-forming process are also disclosed.

A direct positive silver halide photographic material and a method for forming a high contrast image using the same are disclosed, in which a pre-fogged direct positive silver halide emulsion layer contains a salt of a nitrogen-containing compound having at least one pyridine nucleus and at least one pyridinium nucleus. The photographic material, after imagewise exposure, is developed with an alkaline developer containing a developing agent, preferably a reductance compound. The photographic material provides high contrast characteristics having a gamma exceeding 10.

Direct positive silver halide photographic material and method for

A silver halide photographic material is disclosed. The photographic material comprises a support having coated thereon one or more hydrophilic colloidal layers, at least one of the hydrophilic colloidal layers being a negative working silver halide emulsion layer, wherein said silver halide emulsion layer or another hydrophilic colloidal layer contains a water-soluble polymer or copolymer having a quaternary ammonium salt in a repeating unit. The process for forming a high contrast negative image using the photographic material is also disclosed.

High-contrast image forming process

A developer for light-sensitive material capable of processing in common a negative-working light-sensitive lithographic printing plate and a positive-working light-sensitive printing plate as well as a developing agent-containing type silver halide photographic material, is disclosed. The developer comprises an alkali agent, an anionic surface active agent, an antifoggant for a silver halide photographic material, and an alkylene oxide addition product (molecular weight of from 130 to 1200) of an aromatic amine or an aralkyl amine, and has pH of the range of from 11.5 to 13.5.

Growing community of inventors

Konosu, Japan

Yasuhiko Kojima