Method for preparing biaxially stretched polyether ether ketone film
US5242648A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 1, 1992 |
| Grant date | Sep 7, 1993 |
| Priority date | — |
| Expiry date | Apr 1, 2012 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08J2371/00
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
A method for preparing a biaxially stretched polyether ether ketone (PEEK) film having excellent precision in thickness, insulating properties and heat shrinkage from an amorphous PEEK film which includes a first stretching step of roll-stretching the amorphous PEEK film in a temperature range of from 50.degree. C. to (Tg-10).degree. C. in a stretching ratio of from 150% to 350% in the progress direction of the film while a necking phenomenon is caused in the film; a second stretching step of stretching the film in the temperature range of from Tg to 170.degree. C. in a direction at right angles to the stretching direction in the first stretching step in a stretching ratio of from 150% to 350%; and a heat set step of thermally setting the stretched film at two stages in the temperature range of 210.degree.-330.degree. C. and the temperature range of 180.degree.-210.degree. C.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.