Cyanine dyes
US4847385A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 30, 1987 |
| Grant date | Jul 11, 1989 |
| Priority date | — |
| Expiry date | Mar 30, 2007 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/24835
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A cyanine dye having formula (I): ##STR1## wherein R.sup.1 represents Cl, Br or hydrogen; R.sup.2 represents Cl, Br, hydrogen, or a nitro group; R.sup.3 and R.sup.4 each represent a methyl group, an ethyl group, a propyl group or --(CH.sub.2).sub.n OR.sup.5 (in which n is an integer of 2 or 3, and R.sup.5 represents hydrogen or an acetyl group), and X.sup..crclbar. represents an acid anion, provided that the case where R.sup.3 and R.sup.4 are both an identical alkyl group, and R.sup.1 and R.sup.2 are an identical group, is excluded; and PA0 an optical information recording medium including a recording layer comprising the above cyanine dye.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.