Nonaqueous solid particle dye dispersions
US5709983A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 15, 1996 |
| Grant date | Jan 20, 1998 |
| Priority date | — |
| Expiry date | Aug 15, 2016 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03C2200/23
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
Photographic elements are formed by (a) coating a first layer on a transparent support from a coating composition comprising an organic solvent, an alkaline aqueous insoluble, organic solvent soluble film forming binder, and a solid particle non-aqueous dispersion of a filter dye which is substantially insoluble in the organic solvent and readily soluble or decolorizable in alkaline aqueous photographic processing solutions at pH of 8 or above, and (b) coating a second layer on the opposite side of the support relative to the filter dye containing layer from an aqueous coating composition comprising a silver halide emulsion. The solid particle dispersions of photographic filter dyes which are readily soluble or decolorizable in alkali aqueous photographic processing solutions at pH of 8 or above, are prepared by milling the dye in the presence of a non-aqueous liquid in which the dye is substantially insoluble to obtain a solid particle dispersion consisting of fine particles of dye dispersed in a non-aqueous medium. The present invention provides a method to incorporate filter dyes with desired absorbance characteristics for imaging elements, in coating processes that cannot toler…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.