US4820787A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Shaped article of an oriented tetrafluoroethylene polymer
Assignee: Asahi Kasei Corp
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Filing: 1987-03-18
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Granted: 1989-04-11
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Expires: 2007-03-18
Abstract
Abstract A shaped article composed of an at least biaxially orientated tetrafluoroethylene polymer of ultrahigh molecular weight, which has a draw ratio of at least 3.0, a specific gravity of at least 1.8 and an orientation release stress at 200° C. of at least 5 Kg/cm 2 . The shaped article has excellent creep resistant and gas barrier properties, and can advantageously be utilized as a sealant, a lining material, a bearing pad, a sliding pad or the like. The shaped article may be produced by compressing a preformed sheet of a tetrafluoroethylene polymer at a temperature of from 170° to 400° C., under such conditions that plug flow of the polymer is produced, followed by cooling in the compressed state.
Inventors
- 👤 Hiroshi Kataoka
- 👤 Kinya Matsuzawa
- 👤 Hiroji Oda
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 06:23
CPC Classifications
B; B29; B29C; B29C55/00; B29C55/02; B29C55/10; B29C55/12; B29C55/16; B29C43/00; B29C43/003; B29C48/00; B29C48/022; B29C48/03; B29C48/07; B29C48/08; B29C55/18; B29C48/25; B29C48/36; B29C48/475; B29K; B29K2027/00; B29K2027/12; B29K2027/18; B29K2995/00; B29K2995/0037; B29K2995/0088; B29L; B29L2031/00; B29L2031/04
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
60 words
A shaped article comprising a tetrafluoroethylene polymer comprising an at least biaxially oriented tetrafluoroethylene polymer having a number average molecular weight of at least about 10 6 , which has a draw ratio (D) of at least 3.0, a specific gravity of at least 1.8 and an orientation release stress at 200° C. of at least 5 Kg/cm 2 .
Claim 2
Dependent Claim
60 words
A shaped article comprising a tetrafluoroethylene polymer comprising an at least biaxially oriented tetrafluoroethylene polymer having a number average molecular weight of at least about 10 6 , which has a draw ratio (D) of at least 3.0, a specific gravity of at least 1.8 and an orientation release stress at 200° C. of at least 5 Kg/cm 2 .
Claim 3
Dependent Claim
15 words
The shaped article according to claim 1, wherein said draw ratio satisfies the inequality: 3≦D≦20.
Claim 4
Dependent Claim
15 words
The shaped article according to claim 2, wherein said draw ratio satisfies the inequality: 4≦D≦15.
Claim 5
Dependent Claim
15 words
The shaped article according to claim 3, wherein said draw ratio satisfies the inequality: 5≦D≦10.
Claim 6
Dependent Claim
19 words
The shaped article according to claim 1, wherein said orientation release stress is at least 7 Kg/cm 2 .
Claim 7
Dependent Claim
15 words
The shaped article according to claim 1, wherein said specific gravity is at least 2.0.
Claim 8
Dependent Claim
15 words
The shaped article according to claim 6, wherein said specific gravity is at least 2.1.
Claim 9
Dependent Claim
21 words
The shaped article according to claim 1, wherein said at least biaxially oriented tetrafluoroethylene polymer is a multi-axially oriented tetrafluoroethylene polymer.
Claim 10
Dependent Claim
55 words
The shaped article according to claim 1, wherein said biaxially oriented tetrafluoroethylene polymer is comprised of a homopolymer of tetrafluoroethylene or a copolymer of at least 70% by mole of tetrafluoroethylene and a comonomer, said homopolymer and copolymer, respectively, having a number average molecular weight of from about 10 6 to about 10 8 .
Claim 11
Dependent Claim
29 words
The shaped article according to claim 9, wherein said homopolymer and copolymer, respectively, have a number average molecular weight of from about 5×10 6 to about 5×10 7 .
Claim 12
Dependent Claim
63 words
The shaped article according to claim 1, which further comprises at least one filler material selected from the group consisting of a glass fiber, a carbon fiber, graphite, carbon, molybdenum disulfide, a bronze, zirconium oxide, zirconium silicate, an aromatic polyamide fiber and an aromatic polyester fiber, said filler material being present in the article in an amount of up to 60% by weight.
Claim 13
Dependent Claim
13 words
The shaped article according to claim 1, which is in a sealant form.
Claim 14
Dependent Claim
14 words
The shaped article according to claim 1, which is in a lining material form.
Claim 15
Dependent Claim
14 words
The shaped article according to claim 1, which is in a bearing pad form.
Claim 16
Dependent Claim
14 words
The shaped article according to claim 1, which is in a sliding pad form.
Claim 17
Dependent Claim
16 words
The shaped article according to claim 1, which is a solid material containing substantially no voids.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-04-10 | 1992-10-10 | 1993-04-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-04-10 | 1996-10-10 | 1997-04-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-04-10 | 2000-10-10 | 2001-04-11 | $7700.00 | Window Closed / Lapsed |