Development modifiers for silver halide emulsions
US3947273A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 29, 1974 |
| Grant date | Mar 30, 1976 |
| Priority date | — |
| Expiry date | Apr 29, 1994 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S430/15
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
A process is described of improving the development characteristics of photographic silver halide elements by the use of compounds corresponding to the formula: PAC RO(CH.sub.2 CH.sub.2 O).sub.n (CO).sub.m A wherein: PA1 R represents hydrogen, C.sub.1 -C.sub.5 alkyl or (--CO).sub.m --A, PA1 n is an integer of at least 4, PA1 m is 0 or 1, and PA1 A represents, when m is O, sulphoalkyl, carboxyalkyl, or sulphoalkoxycarbonylalkyl, and when m is 1, carboxyalkyl, sulphoalkoxycarbonylalkyl, carboxyalkenyl, sulphoalkoxycarbonylalkenyl, carboxyphenyl, sulphoalkoxycarbonylphenyl or sulphophenyl, The aliphatic hydrocarbon groups having at most 4C-atoms and the carboxyl and sulpho groups being in acid or salt form. The polyethylene glycol derivatives increase developability and sensitivity of black-and-white as well as colour emulsions. They also improve lith-development of photographic "lith"-emulsions.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.