EP0081926A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Coated uniaxially oriented polyester film
Assignee: CNA Holdings LLC
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Filing: 1982-11-22
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Granted: —
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Expires: 2002-11-22
Abstract
Abstract A process for preparing a uniaxial polyester film which comprises: a) extruding a moving molten web of polyester film; and b) quenching the moving web to solidify it in a substantially amorphous form; and c) applying a coating of a dispersed aqueous composition of polyvinyl alcohol or polyurethane to at least a portion of the surface of said film; and d) stretching the moving web in a direction transverse to the direction of motion while heating the web at a temperature of from about its glass transition temperature to about 160 °C; and e) crystallising the transversely restrained moving web by heating it to a temperature in the range of 130 °C to 240 °C without stretching said web; and f) cooling said web to substantially ambient atmospheric temperature.
Inventors
- 👤 Michael Hopper
- 👤 Michael Martin
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-29 16:46
CPC Classifications
B; B05; B05D; B05D7/00; B05D7/02; B05D7/04; C; C08; C08J; C08J7/00; C08J7/04; C08J7/0427; C08J7/043; B05D3/00; B05D3/02; B05D3/0254; B05D3/12; C08J2367/00; C08J2367/02; C08J2429/00; C08J2475/00
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
126 words
A process for preparing a substantially uniaxial polyester film which comprises: a) extruding a moving molten web of polyester film; and b) quenching the moving web to solidify it in a substantially amorphous form; and c) applying a coating of a dispersed aqueous composition of polyvinyl alcohol or polyurethane to at least a portion of the surface of said film; and d) stretching the moving web in a direction transverse to the direction of motion while heating the web at a temperature of from its glass transition temperature to 160°C; and e) crystallising the transversely restrained moving web by heating it to a temperature in the range of 130°C to 240°C without stretching said web; and f) cooling said web to substantially ambient atmospheric room temperature.
Claim 2
Dependent Claim
126 words
A process for preparing a substantially uniaxial polyester film which comprises: a) extruding a moving molten web of polyester film; and b) quenching the moving web to solidify it in a substantially amorphous form; and c) applying a coating of a dispersed aqueous composition of polyvinyl alcohol or polyurethane to at least a portion of the surface of said film; and d) stretching the moving web in a direction transverse to the direction of motion while heating the web at a temperature of from its glass transition temperature to 160°C; and e) crystallising the transversely restrained moving web by heating it to a temperature in the range of 130°C to 240°C without stretching said web; and f) cooling said web to substantially ambient atmospheric room temperature.
Claim 3
Dependent Claim
12 words
The process of claim 1 wherein said polyester film comprises polyethylene terephthalate.
Claim 4
Dependent Claim
18 words
The process of claim 1 or 2 wherein the temperature in step (d) ranges from 80°C to 110°C.
Claim 5
Dependent Claim
16 words
The process of claim 3 wherein the temperature in step (d) ranges from 90°C to 100°C.
Claim 6
Dependent Claim
20 words
The process of any of claims 1 - 4 wherein the temperature of step (e) ranges from 150°C to 180°C.
Claim 7
Dependent Claim
22 words
The process of any of claims 1 - 5 wherein said web is stretched from 2 to 6 times its original width.
Claim 8
Dependent Claim
18 words
The process of claim 6 wherein said web is stretched from 2.5 to 4.5 times its original width.
Claim 9
Dependent Claim
19 words
The process of any of claims 1 - 7 wherein step (e) is performed for five seconds or more.
Claim 10
Dependent Claim
35 words
The process of any of claims 1 - 8 wherein the coating composition comprises an aqueous solution of polyvinyl alcohol wherein said polyvinyl alcohol is present is an amount of from 5oto 10% by weight.
Claim 11
Dependent Claim
19 words
The process of claim 9 wherein said polyvinyl alcohol is hydrolysed in an amount of from 33% to 99%.
Claim 12
Dependent Claim
39 words
The process of claim 9 or 10 wherein the coating composition is applied at a coating weight from .07 to 1.0 dry pound of coating per thousand square feet (0.34 to 4.9 g/ m 2 ) of unstretched film.
Claim 13
Dependent Claim
34 words
The process of any of claims 1 - 8 wherein the coating composition comprises an aqueous dispersion of polyurethane wherein said polyurethane is present in an amount of from 15% to 40% by weight.
Claim 14
Dependent Claim
36 words
The process of claim 12 wherein the coating composition is applied at a coating weight from .07 to .35 dry pound of coating per thousand square feet (0.34 to 1.7 g/m 2 ) of unstretched film.
References Cited (Backward Citations)
No citation records indexed.
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