摘要:
Radiation-sensitive compositions which are especially useful in the production of negative-working lithographic printing plates comprise a photocrosslinkable polymer containing the photosensitive group ##STR1## as an integral part of the polymer backbone and, in an amount sufficient to improve the properties of the composition, both a poly(N-acyl-alkyleneimine) and an unsaturated polyester such as a polyester derived from fumaric acid and a 4,4'-isopropylidenediphenol. The combination of a poly(N-acylalkyleneimine) and an unsaturated polyester improves the properties of the radiation-sensitive composition in regard to such factors as shelf life, image contrast, developability, ink receptivity and reduction in mottle and thereby provides a superior lithographic printing plate.
摘要:
Radiation-sensitive compositions which are especially useful in the production of negative-working lithographic printing plates comprise a photocrosslinkable polymer containing the photosensitive group ##STR1## as an integral part of the polymer backbone and, in an amount sufficient to improve the properties of the composition, both a polymer of vinyl pyrrolidone and an unsaturated polyester such as a polyester derived from fumaric acid and a 4,4'-isopropylidine-diphenol. The combination of a polymer of vinyl pyrrolidone and an unsaturated polyester improves the properties of the radiation-sensitive composition in regard to such factors as shelf life, image contrast, developability and ink receptivity and thereby provides a superior lithographic printing plate.
摘要:
Radiation-sensitive compositions which are especially useful in the production of negative-working lithographic printing plates comprise a photocrosslinkable polymer containing the photosensitive group ##STR1## as an integral part of the polymer backbone and, in an amount sufficient to improve the properties of the composition, an unsaturated polyester such as a polyester derived from fumaric acid and a 4,4'-isopropylidenediphenol. The unsaturated polyester additive improves the properties of the radiation-sensitive composition in regard to processing characteristics and ink receptivity and thereby provides a superior lithographic printing plate.
摘要:
Radiation-sensitive compositions which are especially useful in the production of negative-working lithographic printing plates comprise a photocrosslinkable polymer containing the photosensitive group ##STR1## as an integral part of the polymer backbone and, in an amount sufficient to improve the properties of the composition, a polymer of vinyl pyrrolidone. The polymer of vinyl pyrrolidone improves the properties of the radiation-sensitive composition in regard to such factors as shelf life, image contrast, and developability and thereby provides a superior lithographic printing plate.
摘要:
Radiation-sensitive compositions which are especially useful in the production of negative-working lithographic printing plates comprise a photocrosslinkable polymer containing the photosensitive group ##STR1## as an integral part of the polymer backbone and, in an amount sufficient to improve the properties of the composition, a poly(N-acyl-alkleneimine). The poly(N-acyl-alkyleneimine) improves the properties of the radiation-sensitive composition in regard to such factors as shelf life, image contrast, developability and reduction in mottle and thereby provides a superior lithographic printing plate.
摘要:
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.
摘要:
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.
摘要:
A positive-working lithographic printing plate is used to provide a positive image without a post-exposure baking step and without any floodwise exposure steps. The printing plate includes a layer that is imageable using an infrared radiation laser. This layer consists essentially of a phenolic resin, an infrared radiation absorbing compound, and a dissolution inhibitor that is non-photosensitive and is capable of providing sites for hydrogen bonding with the phenolic moieties of the binder resin. These printing plates are developed with an alkaline composition that includes an alkali metal silicate, a thickener and a fluorosurfactant or phosphate ester hydrotrope.
摘要:
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, a long chain aliphatic amine 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 effective in enhancing the oleophilicity of the image areas of the printing plate.
摘要:
A concentrated developer can be prepared with less than 60 weight % water and still remain in a single phase with little or no haze or precipitation. This developer concentrate also includes a water-soluble or water-miscible organic solvent, one or more alkyl ether carboxylic acid, coconut oil alkanolamine, coconut fatty alcohol polyglycol ether, β-naphtholethoxylate, and block propylene oxide-ethylene oxide in an amount of at least 0.1 and up to 50 weight % solids, and optionally an alkyl naphthalene sulfonate in an amount of up to 40 weight % solids. The developer concentrate can be diluted up to 80:1 or greater with water and used to process imaged lithographic printing plate precursors.