US4839221A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Gasket containing (I) a sheet composition comprising (A) PTFE (B) inorganic powder (C) clay mineral and (II) a metal support for the sheet
Assignee: Nichias Corp
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Filing: 1987-10-09
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Granted: 1989-06-13
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Expires: 2007-10-09
Abstract
Abstract Use of a composition comprising a polytetrafluoroethylene resin and a fine inorganic powder for a gasket, said composition being characterized in that the polytetrafluoroethylene resin is at least 5% by weight and the fine inorganic powder is at least 40% by weight, based on the total amount of the polytetrafluoroethylene resin and the fine inorganic powder; the total amount of the polytetrafluoroethylene resin and the fine inorganic powder is at least 80% by weight based on the entire amount of the composition; and the polytetrafluoroethylene resin and the fine inorganic powder are mutually uniformly dispersed and mixed with each other.
Inventors
- 👤 Hiroshi Asaumi
- 👤 Zenji Shimura
- 👤 Takehiro Yoshida
- 👤 Kenji Tadakuma
- 👤 Shinzaburo Suzuki
- 👤 Norio Takada
- 👤 Kenichi Nakamura
- 👤 Takene Hirai
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 15:05
CPC Classifications
F; F16; F16J; F16J15/00; F16J15/02; F16J15/06; F16J15/10; F16J15/12; F16J15/121; F16J15/122; Y; Y10; Y10S; Y10S277/00; Y10S277/935; Y10S277/936; Y10S277/938; Y10S277/944; Y10S277/945; Y10S277/946; Y10T; Y10T428/00; Y10T428/25; Y10T428/252; Y10T428/31504; Y10T428/3154; Y10T428/31544; Y10T428/31678; Y10T428/31692; Y10T428/31699; Y10T428/31707; Y10T442/00; Y10T442/60; Y10T442/654; Y10T442/656; Y10T442/699
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
117 words
A gasket, comprising a sheet of a composition consisting essentially of a fibrillated polytetrafluoroethylene resin and a fine inorganic powder having an average particle size of not larger than 100 μm and containing at least 30% by weight of a clay mineral, based on the total weight of the fine inorganic powder, said composition characterized in that the polytetrafluoroethylene resin is at least 5% by weight and the fine inorganic powder is at least 40% by weight, based on the total amount of the polytetrafluoroethylene resin and the fine inorganic powder, the polytetrafluoroethylene resin and the fine inorganic powder are mutually uniformly dispersed and mixed with each other, and further comprising a metal support for said sheet.
Claim 2
Dependent Claim
117 words
A gasket, comprising a sheet of a composition consisting essentially of a fibrillated polytetrafluoroethylene resin and a fine inorganic powder having an average particle size of not larger than 100 μm and containing at least 30% by weight of a clay mineral, based on the total weight of the fine inorganic powder, said composition characterized in that the polytetrafluoroethylene resin is at least 5% by weight and the fine inorganic powder is at least 40% by weight, based on the total amount of the polytetrafluoroethylene resin and the fine inorganic powder, the polytetrafluoroethylene resin and the fine inorganic powder are mutually uniformly dispersed and mixed with each other, and further comprising a metal support for said sheet.
Claim 3
Dependent Claim
15 words
The gasket according to claim 1, wherein the clay mineral is a kaolin clay mineral.
Claim 4
Dependent Claim
17 words
The gasket according to claim 2, wherein the kaolin clay mineral is kaolinite, halloysite or hydrated halloysite.
Claim 5
Dependent Claim
29 words
The gasket according to claim 1, wherein the metal support is selected from the group consisting of a rugged metal plate, a meshed metal plate and a metal net.
Claim 6
Dependent Claim
17 words
The gasket according to claim 1, wherein the gasket is a gasket for an automobile engine head.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-06-12 | 1992-12-12 | 1993-06-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-06-12 | 1996-12-12 | 1997-06-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-06-12 | 2000-12-12 | 2001-06-13 | $7700.00 | Window Closed / Lapsed |