US4096227A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for producing filled porous PTFE products
Assignee: W.L. Gore and Associates Inc
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Filing: 1975-12-03
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Granted: 1978-06-20
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Expires: 1995-12-03
Abstract
Abstract This invention provides a tetrafluoroethylene polymer in a porous form which has an amorphous content exceeding about 5% and which has a micro-structure characterized by nodes interconnected by fibrils. The material has high porosity and high strength. It can be used to produce all kinds of shaped articles such as films, tubes, rods, and continuous filaments. Laminations can be employed and impregnation and bonding can readily be used to produce a large variety of articles. Compressed articles of very high strength can also be produced from these porous forms.
Inventors
- 👤 Robert W. Gore
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 19:56
CPC Classifications
C; C08; C08J; C08J5/00; C08J5/18; B; B01; B01D; B01D71/00; B01D71/06; B01D71/30; B01D71/32; B01D71/36; B29; B29C; B29C48/00; B29C48/022; B29C55/00; B29C55/005; B29C55/02; B29C55/10; B29C55/12; C08J5/12; C08J5/124; H; H01; H01B; H01B3/00; H01B3/18; H01B3/30; H01B3/44; H01B3/443; H01B3/445; B29C48/03; B29C48/05; B29C48/06; B29C48/07; B29C48/08; B29C48/09; B29K; B29K2027/00; B29K2027/12; B29K2027/18; B29K2105/00; B29K2105/04; C08J2327/00; C08J2327/02; C08J2327/12; C08J2327/18
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
99 words
A process for the production of a porous article of manufacture of a polymer of tetrafluoroethylene containing a filler, which process comprises: (a) blending a powder consisting essentially of highly crystalline poly(tetrafluoroethylene) with a filler; (b) extruding said polymer powder and filler using a conventional lubricated extrusion technique to form an extrudate; (c) removing the lubricant from said extrudate by conventional methods; and (d) stretching said extrudate containing unsintered poly(tetrafluoroethylene) and filler at a rate exceeding about 10% per second, said stretching being performed while said extrudate is held at a temperature of about 35° C to 327° C.
Claim 2
Dependent Claim
99 words
A process for the production of a porous article of manufacture of a polymer of tetrafluoroethylene containing a filler, which process comprises: (a) blending a powder consisting essentially of highly crystalline poly(tetrafluoroethylene) with a filler; (b) extruding said polymer powder and filler using a conventional lubricated extrusion technique to form an extrudate; (c) removing the lubricant from said extrudate by conventional methods; and (d) stretching said extrudate containing unsintered poly(tetrafluoroethylene) and filler at a rate exceeding about 10% per second, said stretching being performed while said extrudate is held at a temperature of about 35° C to 327° C.
Claim 3
Dependent Claim
11 words
The process of claim 1 in which said filler is asbestos.
Claim 4
Dependent Claim
12 words
The process of claim 1 in which said filler is carbon black.
Claim 5
Dependent Claim
11 words
The process of claim 1 in which said filler is pigment.
Claim 6
Dependent Claim
11 words
The process of claim 1 in which said filler is mica.
Claim 7
Dependent Claim
11 words
The process of claim 1 in which said filler is silica.
Claim 8
Dependent Claim
12 words
The process of claim 1 in which said filler is titanium dioxide.
Claim 9
Dependent Claim
11 words
The process of claim 1 in which said filler is glass.
Claim 10
Dependent Claim
12 words
The process of claim 1 in which said filler is potassium titanate.
Claim 11
Dependent Claim
13 words
The process of claim 1 in which said filler is a dielectric fluid.
Claim 12
Dependent Claim
12 words
The process of claim 1 in which said filler is a polysiloxane.
Claim 13
Dependent Claim
12 words
The process of claim 1 in which said stretching is performed uniaxially.
Claim 14
Dependent Claim
12 words
The process of claim 1 in which said stretching is performed biaxially.
Claim 15
Dependent Claim
27 words
The process of claim 1 including the subsequent step of heating said porous, stretched, filled article to a temperature above the crystalline melting temperature of said polymer.
References Cited (Backward Citations)
SU240996A1
Cited
SU240997A1
Cited
US2915786A
Cited
JPS4213560B1
Cited
US3544671A
Cited
US3637906A
Cited
US3664915A
Cited
US3953566A
Cited
JPS4834388A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-06-19 | 1981-12-19 | 1982-06-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-06-19 | 1985-12-19 | 1986-06-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-06-19 | 1989-12-19 | 1990-06-20 | $7700.00 | Window Closed / Lapsed |