Toray Industries, Inc.

Nippon Oil Company

Mitsuru Suezawa

Norimasa Ikeda

Akihiro Iihara

Kazuki Goto

Masuichi Eguchi

Masaya Asano

Kimikazu Nagase

Makoto Sasaki

Yukio Kobayashi

Gentaro Ohbayashi

Ken Kawamura

Michihiko Ichikawa

Masahiro Oguni

Shun-ichi Yanagida

Takao Kinashi

Kazuo Kitamura

Seigo Miyaguchi

Shingo Aoki

Akihiko Iihara

Toshihiko Taniguci

Atsuko Kawabe

A waterless planographic printing plate precursor has, on a substrate, at least a photosensitive layer or heat sensitive layer and a silicone rubber layer, which is a waterless planographic printing plate precursor, wherein 1) a color pigment and a pigment dispersant are contained in the silicone rubber layer, 2) the a content of color pigment is 0.1 to 20 vol % in the silicone rubber layer, and 3) the pigment dispersant contains an organic complex compound including a metal and an organic compound.

Waterless planographic printing plate precursor

A waterless planographic printing plate precursor is capable of plate inspection without a post-dyeing step, capable of being handled in a light room and excellent in coloring matter fixing in silicone rubber layer. The waterless planographic printing plate precursor has at least a photosensitive layer or heat sensitive layer and a silicone rubber layer on a substrate, which is a waterless planographic printing plate precursor characterized in that a color pigment is contained in the above-mentioned silicone rubber layer, and it is possible to obtain a more excellent effect by further incorporating, in the above-mentioned silicone rubber layer, a pigment dispersant containing an organic complex compound comprising of a metal and an organic compound. Furthermore, when aluminum and/or titanium is contained as the above-mentioned metal, a more excellent effect can be obtained.

The invention is a directly imageable waterless planographic printing plate precursor comprising: at least a heat insulating layer, a heat sensitive layer, and an ink repellent layer that are provided in that order on a substrate, wherein a transmittance of the heat insulating layer for a light having a wavelength within a range of 400 to 650 nm is at most 15% over the entire range of the wavelength. The invention provides a directly imageable waterless planographic printing plate precursor that allows measurement of the dot area ratio on the printing plate with a densitometer or the like.

Directly imageable waterless planographic printing plate precursor

A directly imageable waterless planographic printing plate, which has at least the heat sensitive layer and an ink repellent layer in this order on a substrate, having a high sensitivity and good image reproducibility and allowing a heat sensitive layer to remain even after development is produced by imagewisely irradiating a precursor of the printing plate with a laser beam, pre-treating the precursor by a pre-treatment liquid containing an amine compound by 0.1 to 30 wt % based on the weight of the entire pre-treatment liquid, and removing the ink repellent layer at the laser beam irradiated area, in this order, such that the heat sensitive layer is at least partially left on the printing plate after completion of the above steps.

Method of producing directly imageable waterless planographic printing plate

The present invention relates to a precursor of waterless planographic printing plates, in which at least a photosensitive layer and a silicone rubber layer are laminated on a substrate in this order, characterized in that said photosensitive layer contains a quinonediazide group-containing polyurethane resin and furthermore, preferably, contains a light-heat converting material. The present invention can provide a precursor of waterless planographic printing plates, which is improved in both image reproducibility and printing durability, and which can be applied to both the method of obtaining a waterless planographic printing plate by ordinary image exposure and the method of obtaining a waterless planographic printing plate by laser irradiation.

Precusor of waterless planographic printing plates

Treating liquid for making a waterless planographic printing plate

The present invention is a water-less lithographic printing plate, in which a photosensitive layer and a silicone rubber layer are laminated in this order on a substrate, characterized in that the photosensitive layer contains the reaction product between a compound with at least one each of phenolic hydroxyl groups and non-phenolic hydroxyl groups and a quinonediazide compound, or contains both the reaction product between a compound with at least one of phenolic hydroxyl groups and a quinonediazide compound, and the reaction product between a compound with at least one of non-phenolic hydroxyl groups and a quinonediazide compound. The water-less lithographic raw plate of the present invention is excellent in image reproducibility and printing durability, and so can be favorably and economically advantageously used also in the commercial web offset printing and the newspaper web offset printing where high printing durability is required.

Water-less quinonediazide lithographic raw plate

The ink composition of waterless plates containing as the vehicle a resin III obtained by a process comprising copolymerizing (component A) a five-membered cyclic compound having a conjugated double bond, such as cyclopentadiene and/or a Diels-Alder adduct thereof, (component B) an .alpha.-olefin, and in addition to this, (component A') an unsaturated aromatic hydrocarbon monomer containing a carbon-carbon double bond and a benzene ring within the molecule to obtain a hydrocarbon resin I, reacting the thus obtained hydrocarbon resin I with (component C) an unsaturated carboxylic acid and/or the anhydride thereof to obtain an acid-modified resin II and then thermally reacting the thus obtained acid-modified resin II with (component D) a phenol resin, or containing a modified resin IV obtained by lengthening the molecular chain of the resin III with (component E) a molecular-chain elongating agent in a hydrocarbon solvent with a boiling point of 200.degree. C. or more, a drying oil or a semi-drying oil or a mixture thereof.

Ink compositions for waterless plates

A dry planographic plate has an image area and a non-image area in the shape of an image. The non-image area is constituted by a silicone rubber layer. The surface of the plate is coated with a thin film containing an organic polymer.

Dry planographic plate with silicon rubber layer and organic polymer

A coating composition comprising (a) a diorganopolysiloxane having 1 to 3 functional groups on each of both ends, (b) a diorganopolysiloxane having no functional group or having 1 to 3 functional groups on one end, and (c) a cross-linking agent having two or more functional groups capable of undergoing condensation or addition reaction with the functional groups is coated together with a solvent onto a printing plate or a printing part. The coating composition is ink-repellent and prevents an area to which ink is not to be applied from staining with ink by being coated onto the area.

Coating composition and the use thereof

Developing a dry planographic printing plate using a propylene oxide derivative.

Growing community of inventors

Otsu, Japan

Mitsuru Suezawa