American Hoechst Corporation

Hoechst Celanese Corporation

Shuchen Liu

Raimund J Faust

Douglas A Seeley

William Jeffers

John E Walls

A developer composition for positive color proofing films containing

Developer composition for positive working color proofing films

A method of producing a light sensitive element wherein a substrate is coated with a photosensitive layer having a particular class of diazonium salts, a colorant and a polyvinyl acetal resin. Upon imagewise exposure it is developed with an aqueous composition of salts and surfactants in the absence of organic solvents.

Process for developing an aqueous alkaline development diazo

An improved negative working photographic element is prepared by coating a suitable substrate with a photosensitive composition comprising an admixture of two light sensitive diazonium salts and a binder composition comprising a polyvinyl acetate resin and a styrene/maleic acid half ester copolymer. Upon imagewise exposure of the element to actinic radiation through a suitable mask, the unexposed portions are removable with an aqueous alkaline developer.

Aqueous developable lithographic printing plates containing an admixture

An improved negative working photographic element is prepared by coating a suitable substrate with a photosensitive composition comprising a light sensitive diazonium salt and a binder composition comprising a polyvinyl acetate resin and a styrene/maleic acid half ester copolymer. Upon imagewise exposure of the element to actinic radiation through a suitable mask, the unexposed portions are removable with an aqueous developer.

Aqueous developable diazo lithographic printing plates with admixture of

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

A color proofing foil of increased developability is provided which comprises a substantially transparent polymeric base sheet having a thin coating of a light sensitive composition on the surface of said sheet comprising a mixture of a colorant, a light sensitive material and an effective amount of anionic surfactant. The anionic surfactant is obtained by the reaction of P.sub.2 O.sub.5 with a condensation product of an alkylene oxide and an organic compound containing a reactive hydrogen. The light sensitive coating compositions of this invention when positive working exhibit greatly increased exposure speed. When negative working they exhibit increased development speed. In both cases, they retain the required good adhesion to film substrates, good scratch resistance, freedom from tack and acceptable resistance to overdevelopment.

Light-sensitive color proofing film with surfactant in a light-sensitive

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.

Growing community of inventors

Clinton, NJ, United States of America

Shuchen Liu