Process of forming silver halide grains
US5145768A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 21, 1989 |
| Grant date | Sep 8, 1992 |
| Priority date | — |
| Expiry date | Dec 21, 2009 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03C2001/0153
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A process of producing silver halide grains by disposing a mixer outside of a reaction vessel for causing a nucleus formation and/or a crystal growth of silver halide grains and containing an aqueous protective colloid solution. The process further includes the steps of: supplying an aqueous solution of a water-soluble silver salt, an aqueous solution of a water-soluble halide(s), and an aqueous solution of a protective colloid to the mixer while controlling the flow rates of the solutions; mixing them while controlling the rotational speed of a stirring blade of the mixer to form fine, silver halide grains; and immediately supplying the fine grains into the reaction vessel to perform the nucleus formation and/or the crystal growth of the silver halide grains in the reaction vessel. The silver halide fine grains thus formed in the mixer are quickly diluted with a liquid withdrawn from the reaction vessel and then the diluted mixture is supplied to the reaction vessel.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.