EP 0569075 A1 19931110 - Method of making tabular silver halide grains.
Title (en)
Method of making tabular silver halide grains.
Title (de)
Verfahren zur Herstellung von tafelförmigen Silberhalogenid-Körnern.
Title (fr)
Procédé pour la fabrication de grains d'halogénure d'argent tabulaires.
Publication
Application
Priority
- EP 93201136 A 19930420
- EP 92201259 A 19920505
Abstract (en)
A photographic material has been coated on at least one side of a support with in at least one photosensitive layer hexagonal and/or circular tabular silver halide emulsion crystals occupying at least 70 % of the total projected area of all grains, having a thickness of 0.15 to 0.30 mu m, a coefficient of variation of the tabular grains between 0.15 and 0.45 and an average aspect ratio of at least 2:1, prepared in the absence of ammonia by growing the nuclei, prepared at a pBr value between 1.0 and 2.0 and consuming less than 10 % by weight of silver nitrate, during a first growth step at a pBr value between 1.0 and 2.5 consuming at least 10 % by weight of silver nitrate and during a second growth step at a pBr value higher than 2.7 during the addition of at least 40% of the total amount of silver nitrate used. The loss in sensitivity and gradation after development of said material in a diluted cheap developer after exposing said photographic material containing said emulsion grains is neglectable in comparison with the characteristics obtained after development in stronger high quality developers.
IPC 1-7
IPC 8 full level
G03C 1/005 (2006.01); G03C 5/16 (2006.01); G03C 5/30 (2006.01)
CPC (source: EP)
G03C 1/0051 (2013.01); G03C 5/16 (2013.01); G03C 5/30 (2013.01)
Citation (search report)
- [X] WO 9118320 A1 19911128 - EASTMAN KODAK CO [US]
- [A] US 4755456 A 19880705 - SUGIMOTO TADAO [JP]
- [A] RESEARCH DISCLOSURE vol. 299, March 1989, HAVANT GB pages 185 - 197 ANONYMOUS : 'Nucleation of Tabular Grain Emulsions at High pBr'
Designated contracting state (EPC)
BE DE FR GB NL
DOCDB simple family (publication)
DOCDB simple family (application)
EP 93201136 A 19930420