Process for the production of aqueous polyurethane dispersions
US4921842A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 9, 1988 |
| Grant date | May 1, 1990 |
| Priority date | — |
| Expiry date | Aug 9, 2008 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08J2375/04
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
The present invention relates to a process for the continuous production of aqueous polyurethane dispersions, i.e. dispersions or suspensions both of pure polyurethanes and of polyurethane ureas, by mixing a product, which has been obtained by reaction of polyisocyanates with compounds having a molecular weight of 400 to about 10,000 and containing at least two isocyanate-reactive groups, with water, characterized in that the mixing of the polyisocyanate reaction product with water is carried out in a co-current reactor, one of the components to be mixed or a mixture containing one of the two components to be mixed being compressed to an initilal pressure of from about 20 to 500 bar and expanded through a coaxially arranged nozzle into the short residence time mixing tube where it is mixed with the other component or with a mixture containing the other component.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.