E.i. Dupont De Nemours and Company

Peter K Sysak

Dennis S Donald

Daniel Ray Fruge

A storage stable and rapid dissolving packaged powder developer of uniform composition is produced by preparing developer or developer precursor solutions and removing solvent to provide powder for packaging in plastic impervious to the atmosphere. Preferably, the solvent is removed by freeze-drying or spray-drying.

Powdered packaged developer

Ionic copolymers of styrene sulfonic acid and maleic acid improve covering power when added to the gelatin binder employed in medical silver halide X-ray emulsions.

Ionic copolymers in photographic light-sensitive silver halide films

Photoimaging compositions comprising (A) a cyclohexadienone compound as defined, and at least one of (B.sub.1) a leuco dye or (B.sub.2) addition polymerizable ethylenically unsaturated monomer. A polymer binder can be present in the compositions. The new imaging compositions are useful in photoimaging products such as proofing papers, printout papers, overlay films and photopolymerizable elements useful for printing and photoresist purposes. The compositions have improved thermal stability.

Photoimaging compositions containing substituted cyclohexadienone

Photopolymerizable coating compositions which contain an ethylenically unsaturated polymerizable compound and a radiation sensitive, free-radical generating system are thermally stabilized to inhibit polymerization at elevated temperature without affecting room temperature photopolymerization by adding to the composition a bis(substituted amino)monosulfide or bis(substituted amino)polysulfide.

Growing community of inventors

Wilmington, DE, United States of America

Peter K Sysak