Process for the production of a cellular composite plastic part
US4582658A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 23, 1984 |
| Grant date | Apr 15, 1986 |
| Priority date | — |
| Expiry date | Jul 23, 2004 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S264/83
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
A first reaction mixture, prepared from (a) isocyanates with isocyanate contents of from 5 to 50% and (b) compounds with molecular weights of from 32 to 10,000 which contain at least two isocyanate-reactive hydrogen atoms, in an equivalent ratio of component "a" to component "b" of 0.8:1 to 5:1, from 0.1 to 20% of a blowing agent and, optionally, other known additives, is introduced into the rigid cavity of a closed mold. After this mixture has become resistant to permeation, but is still compressible, a second reaction mixture, either the same or different from the first reaction mixture, prepared from (c) isocyanates having isocyanate contents of from 5 to 50% and (d) compounds with molecular weights of from 32 to 10,000 which contain at least two isocyanate-reactive hydrogen atoms, in an equivalent ratio of component "c" to component "d" of from 0.8:1 to 5:1, specific internal mold release agents and optionally blowing agents and other additives, is introduced into the mold, such that it surrounds the first mixture and compresses it. A third, optional, reaction mixture, the same as or different from the second mixture, may also be employed in a manner similar to the introduction…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.