Biaxially oriented wholly aromatic polyester film

Plastic and nonmetallic article shaping or treating: processes – Mechanical shaping or molding to form or reform shaped article – Reshaping running or indefinite-length work

Patent

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

528193, B29C 1702, C08G 6302

Patent

active

043339077

ABSTRACT:
A melt-molded film of a wholly aromatic polyester, said film having in its plane two perpendicularly crossing directions in each of which the Young's modulus and strength of the film at 25.degree. C. are at least about 200 kg/mm.sup.2 and at least about 5 kg/mm.sup.2 respectively, the product of the Young's moduli of the film in the two directions being at least 8.times.10.sup.4 (kg/mm.sup.2).sup.2, and said wholly aromatic polyester being substantially linear, having a melt viscosity at about its melting point of at least about 10000 poises, and being composed substantially of recurring units derived from p-hydroxybenzoic acid, recurring units derived from a m- or p-oriented aromatic dicarboxylic acid and recurring units derived from a m- or p-oriented aromatic dihydroxy compound, the proportion of said recurring units derived from p-hydroxybenzoic acid being about 30 to about 70 mole % based on the entire recurring units. This invention provides also a process for producing said film which comprises heating aforesaid wholly aromatic polyester to a temperature above a point at which the polyester is extrusion-moldable and extruding the heated polyester through a slit; and either (i) orienting the extruded film in the extruding direction or machine direction and a direction perpendicular thereto while the heated aromatic polyester resides in said slit or after it has left the slit but before it is cooled to the glass transition temperature of the polyester, of (ii) orienting the extruded film substantially only in the extruding direction or machine direction while the polyester heated at said temperature resides in the slit, or after it has left the slit but before it is cooled to the glass transition temperature of the polyester, and then re-heating the film to a temperature higher than the glass transition temperature of the polyester, and orienting the film in a direction perpendicular to the machine direction.

REFERENCES:
patent: 3637595 (1972-01-01), Cottis et al.
patent: 3778410 (1973-12-01), Kuhfuss et al.
patent: 3980749 (1976-09-01), Cottis et al.
patent: 4064108 (1977-12-01), Inata et al.

LandOfFree

Say what you really think

Search LandOfFree.com for the USA inventors and patents. Rate them and share your experience with other people.

Rating

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

Rate now

     

Profile ID: LFUS-PAI-O-552662

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.