Hoechst Aktiengesellschaft

Agfa-gevaert Ag

American Hoechst Corporation

Agfa Gevaert Nv

Raimund J Faust

Silvia Lutz

Engelbert Pliefke

Douglas A Seeley

Shuchen Liu

William Jeffers

Danuta Eva Allen

Peter Lehmann

Willi-Kurt Gries

Kurt Walter Klupfel

The invention relates to a photocurable, negative-working mixture and a recording material which is obtained therefrom and which is suitable for the production of elastic relief printing plates. The mixture contains a) an amphiphilic elastomeric binder, b) a free-radical-polymerizable compound which is compatible with the binder and which has at least one terminal, ethylenically unsaturated group and a boiling point of over about 100.degree. C. at normal pressure and c) a compound or a combination of compounds which is capable of initiating the polymerization of the compound b) on exposure to actinic light. The binder is made up of the segments A, B, C and X, where:

Photocurable elastomeric mixture and recording material obtained

A graft copolymer of recurring units of (C.sub.6 -C.sub.18)alkyl (meth)acrylate (A), N-vinylpyrrolidone (B), glycidyl (meth)acrylate (C), and glycidyl (meth)acrylate units esterified with (meth)acrylic acid (D) onto which polymeric side chains of units of N-vinylpyrrolidone, (C.sub.1 -C.sub.3)alkyl acrylate and, if appropriate, (C.sub.1 -C.sub.3)alkyl methacrylate are grafted. The polymer is suitable as a binder for colorless, negatively chargeable liquid toners, in particular in combination with graft copolymers of (C.sub.1 -C.sub.6)alkyl (meth)acrylate, (C.sub.6 -C.sub.18)alkyl (meth)acrylate and units in which chains of N-vinyl-pyrrolidone units are grafted onto one of the units mentioned, as a charge control agent. After fixing of the electrophotographically produced toner image, the toners give colorless resist masks or printing screens with a high resistance toward etching agents and solvents.

Graft copolymers and colorless, transparent electrophotographic toners

A graft copolymer of recurring units of (C.sub.6 -C.sub.18)alkyl (meth)acrylate (A), vinylpyridine (B), glycidyl (meth) acrylate (C), and glycidyl (meth) acrylate units esterified with (meth)acrylic acid (D) onto which polymeric side chains of units of vinylpyridine, (C.sub.1 -C.sub.3)alkyl acrylate, and optionally (C.sub.1 -C.sub.3)alkyl methacrylate are grafted. The polymer is suitable as a binder for colorless, positively chargeable liquid toners, in particular in combination with a copolymer of (C.sub.6 -C.sub.18)alkyl (meth) acrylate and hydroxyalkyl (meth)acrylate as charge control agents. After fixing of the electrophotographically produced toner image, the toners give colorless resist masks or printing screens with a high resistance toward etching agents and solvents.

A process for the production of a colored image by an electrophotographic route by electrostatic charging, imagewise exposure to light and toning of a photoconductor material with a colorless transparent toner which includes a colorless polymeric binder and a colorless polymeric charge control agent, and transfer of the toner image to a colored layer which is soluble in a solvent and is on a layer carrier, fixing of the toner image and removal of the areas of the colored layer not covered by the toner image by washing out with a solvent. The process utilizes the high photosensitivity of electrophotographic materials, without the possibility of color falsification due to colored toners. The procedure is simpler compared with known electrophotographic processes, since the same toner can be employed in all steps and does not have to be washed off.

Process for the production of colored images by an electrophotographic

A support material for photosensitive substances, useful in the production of offset-printing plates, is disclosed. The support material comprises mechanically, chemically or electrochemically roughened aluminum or an aluminum alloy in the form of a sheet, a foil or a web, and which is coated on at least one side with a hydrophilic polymer which comprises (a) at least 2 mol% of units having acidic side groups and (b) at least 2 mol% of units having basic side groups which are capable of being protonated.

Support material for offset-printing plates in the form of a sheet, a

The invention relates to a hydrophilic copolymer having the general structure:

Hydrophilic copolymers and their use in reprography

The invention relates to a hydrophilic copolymer having the general structure: ##STR1## in which R.sup.1 denotes H, CH.sub.3 or C.sub.2 H.sub.5,

The invention relates to a thermally crosslinkable hydrophilic copolymer have the general structure:

Thermally crosslinkable hydrophilic copolymers and their use in

This invention relates to an improvement in a photochemical process for the preparation of printing plates wherein a printing plate comprising a photosensitive composition coated on a support is exposed to a pattern of laser light, the intensity of which is modulated in accordance with an input source of information and said printing plate is subsequently developed by removal from said support of that portion of the photosensitive coating composition which is not exposed to said pattern of laser light, the improvement comprising utilizing a pattern of laser light generated by a laser at a wavelength greater than about 450 nm, and utilizing as a photosensitive composition a negative-working condensate of a para-aminobenzene diazonium compound, said compound being present in a quality of at least 25% of the total coating weight.

Dialo printing plate made from laser

This invention relates to a light-sensitive transfer material, comprising a flexible temporary support and a thermoplastic photopolymerizable layer which layer comprises a polymeric, thermoplastic binder which is soluble or at least swellable in aqueous-alkaline solutions, a polyurethane with two terminal acrylic acid or methacrylic acid ester groups which is capable of addition polymerization, and a photoinitiator, the polyurethane corresponding to Formula I ##STR1## wherein --X-- is one of the groups ##STR2## --C.sub.k H.sub.2k --O-- and --C.sub.r H.sub.2r-2 --O-- Y is a saturated aliphatic or cycloaliphatic group with 2 to 12 carbon atoms, and

Photopolymerizable mixture in a transfer element

This invention relates to a photopolymerizable mixture comprising a polymeric binder which is soluble or at least swellable in aqueous-alkaline solutions, a photoinitiator, and a polyurethane with two terminal acrylic acid or methacrylic acid ester groups which is capable of addition polymerization, and corresponds to the following general Formula I ##STR1## wherein --X-- is one of the groups ##STR2## --C.sub.k H.sub.2k --O-- and --C.sub.r H.sub.2r-2 --O--,

Photopolymerizable mixture containing unsaturated polyurethane

This invention relates to a photopolymerizable mixture comprising a polymeric binder which is soluble or swellable in aqueous-alkaline solutions, a photoinitiator, a compound with at least two terminal acrylic or methacrylic acid ester groups and a boiling point above 100.degree. C. which is capable of addition polymerization, and a polyurethane corresponding to the following Formula I ##STR1## wherein --X-- is one of the following groups: ##STR2## Y is a saturated aliphatic or cycloaliphatic group with 2 to 12 carbon atoms,

Photopolymerizable mixture containing polyurethanes

This invention relates to an improvement in a photochemical process for the preparation of printing plates wherein a printing plate comprising a photosensitive composition coated on a support is exposed to a pattern of laser light, the intensity of which light is modulated in accordance with an input source of information, and said printing plate is subsequently developed by removal from said support of that portion of the photosensitive coating composition which is not exposed to said pattern of laser light, the improvement comprising utilizing a pattern of laser light generated by a laser, and utilizing as a photosensitive composition a mixture consisting essentially of: (1) a negative-working condensate of a para-amino benzene diazonium compound present in an effective amount sufficient to sensitize said photosensitive composition to laser light, and (2) a colorant capable of absorbing light in the spectral range between about 450 -550 nm, said colorant selectively sensitizing the condensate to said laser light at a wavelength greater than about 450 nm, and being selected from the group consisting of azo, triarylmethane, xanthene and methine compounds.

Preparation of diazo printing plates using laser exposure

This invention relates to an improvement in a photopolymerizable mixture, comprising a polymeric binder which is soluble or at least swellable in aqueous-alkaline solutions, a compound with at least two acrylic or methacrylic acid ester groups and a boiling point above 100.degree. C. which is capable of addition polymerization, a photoinitiator, and a plasticizer, the improvement being that the plasticizer is a compound corresponding to Formula I ##STR1## wherein R.sub.1 is a hydrogen or halogen atom or an alkyl group with 1 to 4 carbon atoms, R.sub.2 is a hydrogen atom, an OH group, or an alkyl group with 1 to 4 carbon atoms, R.sub.3 is a hydrogen atom or a methyl group, R.sub.4 is an alkyl or alkenyl group with 1 to 20 carbon atoms, and n is zero or a whole number from 1 to 20, and wherein R.sub.4 has at least 4 carbon atoms if n is zero or 1. The invention also relates to a light-sensitive transfer material including the photopolymerizable mixture.

Growing community of inventors

Wiesbaden, Germany

Raimund J Faust