Formation of blocked isocyanurate group-containing polyisocyanates from partially blocked isocyanates
US5939547A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 22, 1997 |
| Grant date | Aug 17, 1999 |
| Priority date | — |
| Expiry date | Dec 22, 2017 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08G18/807
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
The present invention relates to a process for the preparation of blocked polyisocyanates containing isocyanurate groups by PA1 a) reacting 20 to 80 equiv. % of the isocyanate groups of an organic diisocyanate with a pyrazole or triazole blocking agent, PA1 b) trimerizing the remaining unblocked isocyanate groups in the presence of a basic trimerization catalyst until the isocyanate content is less than 2.5% by weight, based on the weight of the blocked polyisocyanate and PA1 c) optionally blocking any remaining isocyanate groups with a blocking agent for isocyanate groups. The present invention also relates to the use of these blocked polyisocyanates for the production of polyisocyanate addition products.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.