Method of preparing diisocyanate composition
US11339121B2 · kind B2 · utility
Assignees
Inventors
Key dates
| Filing date | Dec 4, 2020 |
| Grant date | May 24, 2022 |
| Priority date | — |
| Expiry date | Dec 4, 2040 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02P20/582
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
In the embodiments, an aqueous hydrochloric acid solution instead of hydrogen chloride gas and solid triphosgene instead of phosgene gas may be used in the process of preparing a diisocyanate from a diamine through a diamine hydrochloride. In addition, the embodiments provide processes for preparing a diisocyanate composition and an optical lens, which are excellent in yield and quality with mitigated environmental problems by controlling the size of the diamine hydrochloride composition, the b* value according to the CIE color coordinate of the diamine hydrochloride composition, or the content of water in the diamine hydrochloride composition within a specific range.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.