Preparation of low viscosity small-particle photographic dispersions in gelatin
US5013640A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 15, 1989 |
| Grant date | May 7, 1991 |
| Priority date | — |
| Expiry date | Jun 15, 2009 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S516/922
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
The invention is generally accomplished by utilization of a surfactant for very small particle photographic dispersions. Three types of such surfactants that have been identified are as follows: PA1 Type A--Surfactant comprising 6 to 22 carbon atom hydrophobic tail with one or more attached hydrophilic chains comprising at least 8 oxyethylene and/or glycedyl ether groups that may or may not be terminated with a negative charge such as a sulfate group. PA1 Type B--Block oligomeric surfactants comprising hydrophobic polyoxypropylene blocks (A) and hydrophilic polyoxyethylene blocks (B) joined in the manner of A-B-A, B-A-B, A-B, (A-B).sub.n .tbd.G.tbd.(B-A), or (B-A).sub.n .tbd.G.tbd.(A-B).sub.n, where G is a connective organic moiety and n is between 1 and 3. PA1 Type C--Sugar surfactants, comprising between one to three 6 to 22 carbon atom hydrophobic tail with one or more attached hydrophilic mono or oligosaccharidic chains that may or may not be terminated by a negatively charged group such as a sulfate group. The preferred colloid chemical criterion of the photographic dispersion material in this invention is that they are formed with particle diameters between about 5 nm and 100…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.