Process of making a high molecular weight polyolefin part
US4747990A · kind A · utility
Assignees
Inventors
Key dates
| Filing date | Mar 6, 1986 |
| Grant date | May 31, 1988 |
| Priority date | — |
| Expiry date | Mar 6, 2006 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB29L2031/7532
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
The invention relates to a high molecular weight polyolefin part, particularly for an articular prosthesis and to its production process by shaping in a closed mould. This part, which has a friction surface, has a structure such that the polyolefin chains are oriented parallel to the friction surface, at least in the zone of the part located below or flush with said friction surface. This orientation is obtained during the shaping of the blank of the part in a closed mould having a metal belt, a hemispherical block and a mobile punch, as a result of the choice of shaping conditions, particularly the shaping temperature and the length/transverse dimension ratio of the blank.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.