Method of preparing diisocyanate composition and optical lens
US11518737B2 · kind B2 · utility
Assignees
Inventors
Key dates
| Filing date | Dec 2, 2020 |
| Grant date | Dec 6, 2022 |
| Priority date | — |
| Expiry date | Dec 2, 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 and an organic solvent 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 total content of metals, cations, or anions in a diamine hydrochloride composition.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.