Method of making soluble squaraine dyes
US5625062A · kind A · utility
2Cited by
6References
20Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | May 29, 1996 |
| Grant date | Apr 29, 1997 |
| Priority date | — |
| Expiry date | May 29, 2016 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07D239/70
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
The present invention provides a novel process for the production of organic solvent soluble squaraine dyes. More specifically, the invention describes how a difficult to prepare tetrahydroxy squaraine intermediate can be prepared in an organic solvent system in the presence of water. This intermediate can then be esterified in pyridine to form the soluble squaraine dye which can then be easily isolated from the reaction mixture. The invention also provides the dyes prepared according to this method.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.