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US4687615A
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Method of producing biaxially oriented tubular polyetheretherketone films
Assignee: Okura Industrial Co Ltd
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Filing: 1985-09-16
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Granted: 1987-08-18
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Expires: 2005-09-16
Abstract
Abstract A method of producing biaxially oriented tubular polyetheretherketone films having good optical and mechanical properties and heat resistance, by rapidly quenching at a rate of at least 24 DEG C. per second an unoriented tubular polyetheretherketone film as melt-extruded through a circular die thereby imparting a crystallinity of not greater than 10% to the film, and continuously introducing the thus produced film into the space between a feed nip roll pair and a pull nip roll pair while reheating the film externally to a temperature of 60 DEG -140 DEG C. and allowing the film to expand under the influence of the internal pressure to an areal draw ratio of 4-36, to thereby attain biaxial orientation.
Inventors
- 👤 Kazuo Kondo
- 👤 Satoshi Maruyama
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 15:34
CPC Classifications
B; B29; B29C; B29C48/00; B29C48/001; B29C48/0018; B29C48/25; B29C48/88; B29C48/885; B29C48/90; B29C48/901; B29C48/903; B29C48/91; B29C48/911; B29C48/9115; B29C48/912; B29C48/9135; B29C48/914; B29C48/92; C; C08; C08J; C08J5/00; C08J5/18; B29C48/03; B29C48/07; B29C48/08; B29C48/09; B29C48/10; B29K; B29K2071/00; B29K2995/00; B29K2995/0037; B29K2995/005
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
124 words
A method of producing biaxially oriented tubular polyetheretherketone films having good optical and mechanical properties and heat resistance, comprising rapidly quenching at a rate of at least 24° C. per second, an unoriented tubular polyetheretherketone film as melt-extruded through a circular die, thereby imparting a crystallinity of not greater than 10% to the film, and continuously introducing the thus-produced film into the space between a feed nip roll pair and a pull nip roll pair while reheating the film externally to a temperature of 60°-140° C. and introducing air into the hollow interior of said tubular film to allow the film to expand under the influence of the internal pressure thus created to an areal draw ratio of 4-36, to thereby attain biaxial orientation.
Claim 2
Independent Claim
124 words
A method of producing biaxially oriented tubular polyetheretherketone films having good optical and mechanical properties and heat resistance, comprising rapidly quenching at a rate of at least 24° C. per second, an unoriented tubular polyetheretherketone film as melt-extruded through a circular die, thereby imparting a crystallinity of not greater than 10% to the film, and continuously introducing the thus-produced film into the space between a feed nip roll pair and a pull nip roll pair while reheating the film externally to a temperature of 60°-140° C. and introducing air into the hollow interior of said tubular film to allow the film to expand under the influence of the internal pressure thus created to an areal draw ratio of 4-36, to thereby attain biaxial orientation.
Claim 3
Dependent Claim
27 words
A method as claimed in claim 1, wherein the unoriented film is rapidly cooled by means of a liquid or a combination of a liquid and air.
Claim 4
Dependent Claim
12 words
A method as claimed in claim 2, wherein the liquid is water.
Claim 5
Dependent Claim
18 words
A method as claimed in claim 1, wherein the film is reheated to a temperature of 80°-120° C.
Claim 6
Dependent Claim
19 words
A method as claimed in claim 1, wherein the film is expanded to an areal draw ratio of 9-25.
Claim 7
Dependent Claim
36 words
A method according to claim 1, wherein the extruded film is cooled at a rate of at least 30° C. per second and an unoriented film having a crystallinity of not greater than 6% is produced.
Claim 8
Dependent Claim
30 words
A method according to claim 6 wherein the film is reheated to a temperature of 80°-120° C. and wherein the film is expanded to an areal draw ratio of 9-25.
Claim 9
Independent Claim
48 words
A method of producing biaxially oriented polyetheretherketone films having good mechanical and optical properties, which comprises biaxially drawing an unoriented tubular film of the polyetheretherketone having a crystallinity of not greater than 10% at a temperature of 60°-140° C. to an areal draw ratio of 4 to 36.
Claim 10
Independent Claim
48 words
A method of producing biaxially oriented polyetheretherketone films having good mechanical and optical properties, which comprises biaxially drawing an unoriented tubular film of the polyetheretherketone having a crystallinity of not greater than 10% at a temperature of 60°-140° C. to an areal draw ratio of 4 to 36.
Claim 11
Dependent Claim
17 words
A method according to claim 8, wherein the film is reheated to a temperature of 80°-120° C.
Claim 12
Dependent Claim
18 words
A method according to claim 8, wherein the film is drawn to an areal draw ratio of 9-25.
Claim 13
Dependent Claim
18 words
A method according to claim 8, wherein the unoriented film has a crystallinity of not greater than 6%.
References Cited (Backward Citations)
US3142092A
Cited
US3278663A
Cited
US3671617A
Cited
US3857917A
Cited
US4120931A
Cited
US4451306A
Cited
US4435350A
Cited
GB2145652A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-08-17 | 1991-02-16 | 1991-08-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-08-17 | 1995-02-16 | 1995-08-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-08-17 | 1999-02-16 | 1999-08-18 | $7700.00 | Window Closed / Lapsed |