EP 0704751 A1 19960403 - Method for making negative lith images or direct positive images
Title (en)
Method for making negative lith images or direct positive images
Title (de)
Verfahren zur Herstellung von Lithnegativ- oder Direktpositivbildern
Title (fr)
Procédé de préparation d'images négatives de type lithographique ou d'images positives directes
Publication
Application
Priority
- EP 95202566 A 19950922
- EP 94202772 A 19940927
Abstract (en)
A method is provided for making negative lithographic images or direct-positive images by the steps of image-wise exposing a photographic light-sensitive silver halide material comprising a support, at least one internal latent image-type silver halide emulsion layer (in the case of direct-positive materials) or surface latent image-type silver halide emulsion layer (in the case of lithographic materials) and development-nucleating amounts of a compound or a precursor thereof, said compound having at least one quaternary heterocyclic ring system comprising at least three rings including a dihydropyridinium ring wherein carbon-nitrogen and carbon-carbon double bonds are also part of an aromatic ring being one of said three rings and wherein said double bonds and nitrogen atom in said dihydropyridinium ring are incorporated into annelated conjugated ring systems; and developing said exposed photographic material in an alkaline surface developer, wherein said precursor is rapidly converted into a ring system as defined hereinbefore.
IPC 1-7
IPC 8 full level
G03C 1/06 (2006.01); G03C 1/485 (2006.01)
CPC (source: EP)
G03C 1/067 (2013.01); G03C 1/48546 (2013.01); G03C 1/061 (2013.01)
Citation (search report)
- [XY] EP 0518352 A1 19921216 - DAINIPPON INK & CHEMICALS [JP]
- [Y] US 4471044 A 19840911 - PARTON RICHARD L [US], et al
- [Y] EP 0381160 A2 19900808 - FUJI PHOTO FILM CO LTD [JP]
- [DA] US 5338658 A 19940816 - HIRANO SHIGEO [JP]
Designated contracting state (EPC)
BE DE FR GB NL
DOCDB simple family (publication)
DOCDB simple family (application)
EP 95202566 A 19950922