Production of wholly aromatic polyester film

Details Production of wholly aromatic polyester film Production of wholly aromatic polyester film

1991-01-31

1992-02-25

Thurlow, Jeffery

Plastic and nonmetallic article shaping or treating: processes

Direct application of fluid pressure differential to...

Production of continuous or running length

2641761, 2642902, 2642107, B29C 4720

Patent

active

050911384

ABSTRACT:
A wholly aromatic polyester film, (A) which is made of a wholly aromatic polyester consisting essentially of the following recurring units I and II ##STR1## wherein the aromatic ring may be optionally substituted with at least one substituent selected from the group consisting of an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, a halogen atom and a phenyl group, said wholly aromatic polyester comprising 10 to 90 mol % of the recurring unit I and 90 to 10 mol % of the recurring unit II, being capable of forming an optically anisotropic melt phase, and having a melt strength at a temperature 20.degree. C. higher than its transition temperature to liquid crystal of at least 2.0 g/mm.sup.2 ; (B) said film having an oxygen permeability of not more than 1.0 cc.20.mu./m.sup.2.day.atm at a temperature 20.degree. C. and a relative humidity 65%; and (C) said film having thermal shrinkages both in the machine direction and in a direction perpendicular thereto of not more than 1% at a temperature 250.degree. C. Said wholly aromatic polyester film can be produced by melt-extruding a wholly aromatic polyester to form into a film under conditions that a shear rate applied to the wholly aromatic polyester in a molten state at the exit of the molding die is not less than 500 sec.sup.-1.

REFERENCES:
patent: 4161470 (1979-07-01), Calundann
patent: 4325903 (1982-04-01), Wissbrun et al.
patent: 4332759 (1982-06-01), Ide
patent: 4574066 (1986-03-01), Gibbon et al.
patent: 4581399 (1986-04-01), Yoon
patent: 4614629 (1986-09-01), Economy et al.
patent: 4673724 (1987-06-01), Endoh et al.
patent: 4851503 (1989-07-01), Matsumoto et al.
patent: 4973442 (1990-11-01), Harvey et al.
Derwent Publications Ltd., London, GB, Abstract JP-A-61 102 234 (Asahi Chemical).

Affiliated with

Also associated with

Rating

Production of wholly aromatic polyester film does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Production of wholly aromatic polyester film, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Production of wholly aromatic polyester film will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-1891261