Method and device for the manufacture of a high optical quality transparent sheet or plastic
US4830806A · kind A · utility
3Cited by
9References
14Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Jun 24, 1987 |
| Grant date | May 16, 1989 |
| Priority date | — |
| Expiry date | Jun 24, 2007 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB29K2995/0026
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
The invention is directed to the method, products and apparatus for the manufacture of a high optical quality sheet of plastic comprising a polyurethane layer having energy-absorbing properties obtained by reactive pouring or reactive pulverization of the reaction components. In accordance with the invention, the polyurethane layer is treated, while it is in a state of ongoing polymerization corresponding to an NCO/CH ratio of less than 0.7, with water in a liquid or vapor form and then subsequently, after rolling with an interpolated film, stocking and unrolling, the layer is subjected to heat treatment.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.