Diamine composition, and method of preparing diisocyanate composition
US11760719B2 · kind B2 · utility
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Key dates
| Filing date | Dec 4, 2020 |
| Grant date | Sep 19, 2023 |
| Priority date | — |
| Expiry date | Jan 4, 2041 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02P20/582
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
A diamine composition comprising a benzylmonoamine having a methyl group in an amount of 10 ppm to 2,000 ppm in the composition and use thereof for the preparation of a diisocyanate composition and an optical material. A process for preparing a diisocyanate composition wherein the b* value according to the CIE color coordinate of the diamine composition is adjusted to a specific range, whereby the yield and purity of the diisocyanate composition and the optical characteristics of the final optical lens are enhanced. Use of the process for the diisocyanate composition for preparing a plastic optical lens of high quality.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.