EP 0649051 A1 19950419 - Preparation method of silver bromide or silver bromoioidide light-sensitive emulsions and material comprising said emulsions.
Title (en)
Preparation method of silver bromide or silver bromoioidide light-sensitive emulsions and material comprising said emulsions.
Title (de)
Herstellungsverfahren für lichtempfindliche Silberhalogenidemulsion und diese Emulsionen enthaltendes Material.
Title (fr)
Méthode de préparation des émulsions à l'halogénure d'argent sensible à la lumière et matériau comprenant ces émulsions.
Publication
Application
Priority
- EP 94202580 A 19940908
- EP 93202679 A 19930916
Abstract (en)
A method is disclosed to prepare a light-sensitive regular silver bromide or silver bromoiodide emulsion, wherein said method comprises the following the steps: precipitating silver bromide or silver bromoiodide by means of the double-jet or triple-jet technique in colloidal silica having a particle size from 0.003 mu m to 0.30 mu m as a protective colloid in the absence of any polymeric compound(s) comprising gelatin or its derivatives capable of forming hydrogen bridges with colloidal silica, except for polythioether compounds, but always in the presence of an onium compound, except for an ammonium compound, wherein the ratio by weight of said colloidal silica to the said onium compound(s) is between 3 and 30, and, optionally, in the presence of a crystal growth modifier, controlling the nucleation and growth steps by means of variable flow rate(s) of the aqueous solutions of silver nitrate and halide salts and/or by means of constant pAg-values during the said steps in the vessel in order to determine the number of nuclei quantitatively in the nucleation step and to avoid renucleation in the growth step, desalting the reaction medium and redispersing the silver halide, chemically ripening the silver halide crystals and adjusting the ratio by weight of the colloidal silica sol to the amount of silver halide, expressed as the equivalent amount of silver nitrate to a value of at least 0.03 at every moment throughout the precipitation stage.
IPC 1-7
IPC 8 full level
G03C 1/015 (2006.01); G03C 1/04 (2006.01); G03C 1/07 (2006.01)
CPC (source: EP)
G03C 1/015 (2013.01); G03C 1/04 (2013.01); G03C 1/07 (2013.01); G03C 2001/0157 (2013.01)
Citation (search report)
- [DXY] EP 0392092 A1 19901017 - AGFA GEVAERT NV [BE]
- [DY] EP 0528476 A1 19930224 - AGFA GEVAERT NV [BE]
- [DA] EP 0517961 A1 19921216 - AGFA GEVAERT NV [BE]
Designated contracting state (EPC)
BE DE FR GB NL
DOCDB simple family (publication)
DOCDB simple family (application)
EP 94202580 A 19940908