Method for producing a thermoplastic polymeric sheet
US4594203A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 13, 1984 |
| Grant date | Jun 10, 1986 |
| Priority date | — |
| Expiry date | Mar 13, 2004 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB29C48/07
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
The present invention relates to a method for producing a thermoplastic polymeric sheet, wherein a molten thermoplastic polymer is extruded from an extrusion die in the form of a sheet onto a moving quenching member, with an electric potential difference being established between the surface of the moving quenching member and the extrusion die, whereby the polymer is caused to electrostatically solidify and adhered to the surface of the quenching member. The contact area of the polymeric sheet with the moving quenching member is held in an atmosphere of a gas which posesses better insulating properties than standard air. Thus the present invention provides a useful method that can produce, at higher speeds than conventional method, polymer sheets of high surface quality which avoid the operational problems encountered in the conventional methods.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.