Melt crystallization process for preparing high trans, trans-isomer containing 4,4'-diisocyanato dicyclohexylmethane
US5175350A · kind A · utility
1Cited by
7References
9Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Feb 14, 1992 |
| Grant date | Dec 29, 1992 |
| Priority date | — |
| Expiry date | Feb 14, 2012 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07C2601/14
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
The present invention is directed for preparing a 4,4'-diisocyanato dicyclohexylmethane which contain a relatively high amount of the trans,trans-isomer. The process broadly comprises (a) melting a mixture of 4,4'-diisocyanato dicyclohexyl-methane isomers, (b) cooling the melted mixture to form: (1) a liquid phase and (2) a solid phase, (c) removing said liquid phase, which is a commercially viable product itself, (d) heating the solid phase and removing that portion of the solid phase which has melted, and (e) recovering that portion of said solid phase which has not melted by heating the remaining portion.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.