Polyisocyanate compound, process for producing the same and optical materials using the same
US6194603A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 28, 1999 |
| Grant date | Feb 27, 2001 |
| Priority date | — |
| Expiry date | Jul 28, 2019 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B1/04
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
A novel polyisocyanate compound, which compound is useful as a starting material for an optical material having excellent optical characteristics such as a high refractive index and a low dispersion, and a process for producing this compound at good efficiency. Specifically, a polyisocyanate compound represented by general formula (I): ##STR1## wherein Z represents a direct bond, or --CH.sub.2 --. The invention also relates to processes for producing the desired polyisocyanate compound through a tricarboxylic acid ester and a tricarbonyl hydrazide using a dihalogeno-aliphatic carboxylic acid lower alkyl ester and a thioglycolic acid lower alkyl ester. In addition, the invention relates to optical materials, such as lenses, etc., made by a polyaddition reaction of compounds of formula (I) and other monomers.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.