Photographic material having improved color reproduction
US6558893B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 17, 2000 |
| Grant date | May 6, 2003 |
| Priority date | — |
| Expiry date | Nov 17, 2020 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03C1/29
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
This invention comprises a silver halide photographic material comprising at least one silver halide emulsion comprising silver halide grains having associated therewith a combination of two or more dyes comprising:(a) a first dye which is a cyanine dye of formula Ia and has a net charge of zero or −1  wherein the substituents are as defined in the specification;(b) a second dye which has at least one substituent that has a positive charge, and is a cyanine dye a merocyanine dye, arylidene dye, complex cyanine dye, complex merocyanine dye, homopolar cyanine dye, hemicyanine dye, styryl dye, hemioxonol dye, oxonol dye, anthraquinone dye, triphenylmethane dye, azo dye type, azomethines, or a coumarin dye, with the proviso that if the second dye is a cyanine dye, it is of formula IIa:  wherein the substituents are as defined in the specification; and wherein(c) the wavelength of maximum light absorption, in nanometers (nm), of the first dye and the wavelength of maximum light absorption of the second dye differ by at least 10 nm.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.