Eastman-kodak Company

Kodak Polychrome Graphics, Gmbh

Kodak Polcyhrome Graphics LLC

John E Walls

Paul R West

Gary R Miller

Jeffery Allen Gurney

Raymond W Ryan, Jr

Larry D LeBoeuf

Thomas R Jordan

Melanie A Felker

A positive image can be obtained from a positive-working element that is sensitive to infrared radiation. The element comprises an imaging layer containing an alkali-soluble reactive resin (such as a phenolic resin), an infrared radiation absorbing compound, a thermochemical acid generating compound, and a dissolution inhibitor that has acid-cleavable C&mdash;O&mdash;C groups. Upon laser exposure, a Bronsted acid is generated which then breaks the bonds of the C&mdash;O&mdash;C groups, allowing the exposed regions of the reactive resin to be solubilized in an alkaline developer solution.

Positive-working imaging composition and element and method of forming positive image with a laser

Photosensitive polyesters having dye moieties incorporated into the polyester backbone are disclosed. The photosensitive polyesters contain an unsaturated photosensitive moiety comprising photopolymerizable &mdash;CH&boxH;CH&mdash;CO&mdash; groups and dye moieties derived from dyes that are copolymerizable diols. Negative-working photosensitive elements, such as negative-working printing plates, can be prepared using these photosensitive polyesters.

Photosensitive compositions and elements comprising dyed photosensitive polyesters

A positive image can be obtained from a positive-working element that is sensitive to infrared radiation. The element comprises an imaging layer containing an alkali-soluble reactive resin (such as a phenolic resin), an infrared radiation absorbing compound, a thermochemical acid generating compound, and a dissolution inhibitor that has acid-cleavable C--O--C groups. Upon laser exposure, a Bronsted acid is generated which then breaks the bonds of the C--O--C groups, allowing the exposed regions of the reactive resin to be solubilized in an alkaline developer solution.

1Postitve-working imaging composition and element and method of forming

Aqueous alkaline developing compositions useful in the development of negative-working lithographic printing plates are comprised of an organic solvent, an anionic surface active agent, an alkali metal tetraborate, an aliphatic monocarboxylic acid, an aliphatic dicarboxylic acid, an alkali metal citrate, a poly(alkylene glycol), an alkali metal salt of an hydroxylated aromatic carboxylic or sulfonic acid and sufficient alkaline buffering system to provide an alkaline pH. The developing composition is resistant to oxidation, highly effective in dissolution-type processing, able to effectively desensitize the background areas of the printing plate, and capable of preventing excessive deposits in a processing machine and rapidly redissolving deposits that do form.

Aqueous developer for lithographic printing plates which exhibits

Improved lithographic printing plates are comprised of an aluminum support, a hydrophilic barrier layer comprised of a copolymer of about 40 to about 90 mole percent vinylphosphonic acid and about 10 to about 60 mole percent acrylamide overlying said support, and an image-forming layer capable of providing a lithographic printing surface overlying said barrier layer.

Lithographic printing plates having a hydrophilic barrier layer

A scratch remover and desensitizer composition which is especially useful in treating scratches in non-image areas of lithographic printing plates and desensitizing such scratched areas so they will not accept ink is comprised of an alkali metal silicate, a tribasic phosphate salt, an organic solvent, a nonionic surfactant and water.

Scratch remover and desensitizer composition for use with lithographic

A negative-working lithographic printing plate having a radiation-sensitive layer comprising a diazo resin, an acid-substituted ternary acetal polymer and an unsaturated polyester is developed with an aqueous developing composition comprising an organic solvent, an anionic surface active agent, sodium oxalate, sodium nitrate or an alkali metal tetraborate an aliphatic monocarboxylic acid, an aliphatic dicarboxylic acid and sufficient alkaline buffering system to provide an alkaline pH. The method effectively avoids problems of blinding and background sensitivity which are of critical concern in the printing art.

Method for developing lithographic printing plates

Aqueous alkaline developing compositions useful in the development of negative-working lithographic printing plates are comprised of an organic solvent, an anionic surface active agent, sodium oxalate, sodium nitrate or an alkali metal tetraborate, an aliphatic monocarboxylic acid, an aliphatic dicarboxylic acid and sufficient alkaline buffering system to provide an alkaline pH. The developing composition is resistant to oxidation, highly effective in dissolution-type processing, and able to effectively desensitize the background areas of the printing plate.

Aqueous developer for lithographic printing plates with improved

Photosensitive compositions, useful in lithographic printing plates which can be developed with aqueous developing solutions, comprise a diazo resin, an acid-substituted ternary acetal polymer, and a copolyester of an unsaturated dicarboxylic acid and an oxyalkylene ether of an alkylidene diphenol. The acid-substituted ternary acetal polymers are comprised of recurring units which include three six-membered cyclic acetal groups, one of which is unsubstituted or substituted with an alkyl or hydroxyalkyl group, another of which is substituted with an aromatic or heterocyclic moiety, and a third of which is substituted with an acid group, an acid-substituted alkyl group or an acid-substituted aryl group.

Photosensitive compositions and lithographic printing plates containing

Photosensitive compositions, useful in lithographic printing plates which can be developed with aqueous developing solutions, comprise a diazo resin and a binary acetal polymer which functions as a polymeric binder. The binary acetal polymers are comprised of recurring units which include two six-membered cyclic acetal groups, one of which is unsubstituted or substituted with an alkyl or hydroxyalkyl group and the other of which is substituted with an aromatic or heterocyclic moiety.

Photosensitive compositions, useful in lithographic printing plates which can be developed with aqueous developing solutions, comprise a diazo resin and an acid-substituted ternary acetal polymer which functions as a polymeric binder. The acid-substituted ternary acetal polymers are comprised of recurring units which include three six-membered cyclic acetal groups, one of which is unsubstituted or substituted with an alkyl or hydroxyalkyl group, another of which is substituted with an aromatic or heterocyclic moiety, and a third of which is substituted with an acid group, an acid-substituted alkyl group or an acid-substituted aryl group.

Novel acid-substituted ternary acetal polymers are comprised of recurring units which include three six-membered cyclic acetal groups, one of which is unsubstituted or substituted with an alkyl or hydroxyalkyl group, another of which is substituted with an aromatic or heterocyclic moiety, and a third of which is substituted with an acid group, an acid-substituted alkyl group or an acid-substituted aryl group. The acid-substituted ternary acetal polymers are advantageously employed in photosensitive compositions in which they are utilized in combination with diazo resins. Such photosensitive compositions are especially well adapted for use in lithographic printing plates which can be developed with aqueous developing solutions.

Acid-substituted ternary acetal polymers useful in photosensitive

Novel binary acetal polymers are comprised of recurring units which include two six-membered cyclic acetal groups, one of which is unsubstituted or substituted with an alkyl or hydroxyalkyl group and the other of which is substituted with an aromatic or heterocyclic moiety. The binary acetal polymers are advantageously employed in photosensitive compositions in which they are utilized in combination with diazo resins. Such photosensitive compositions are especially well adapted for use in lithographic printing plates which can be developed with aqueous developing solutions.

Binary acetal polymers useful in photosensitive compositions and

A single-phase homogeneous composition for the protection of lithographic printing plate surfaces is provided which comprises an aqueous solution of

Composition for protecting the surface of lithographic printing plates

An aqueous developing composition including

Growing community of inventors

Fort Collins, CO, United States of America

John E Walls