Thin transparent polytetrafluoroethylene film and production process thereof.

摘要

Disclosed herein is a thin transparent polytetrafluoroethylene film defined as follows:
<UnorderedLists id="ula01" listStyle="none"><ListItem>(1) a film thickness of 0.1-100 µm;</ListItem><ListItem>(2) a parallel light transmittance of at least 70% (as measured in accordance with JIS K 7105); and</ListItem><ListItem>(3) a tensile strength of at least 1 kg/mm<Sup>2</Sup> (as measured in accordance with JIS K 6887 except for the use of a pulling speed of 10 mm/min.).</ListItem></UnorderedLists>

It is produced by fluorinating with a fluorine gas a thin film formed from a solution of a fluoroethylene polymer having an inherent viscosity of at least 2.5 dl/g (as measured at a temperature of 30°C and a solution concentration of 0.4 g/dl) in accordance with the casting process and having a thickness of 0.1-100 µm.