US4792491A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Gaskets
Assignee: T&N Materials Research Ltd
•
Filing: 1986-11-26
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Granted: 1988-12-20
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Expires: 2006-11-26
Abstract
Abstract Graphite gaskets with an improved release characteristic are treated with a finely powdered release agent such a graphite powder which is then pressed into the gasket surface.
Inventors
- 👤 Alan Atkinson
- 👤 Katryna Dearden
- 👤 Janet Lancaster
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 02:14
CPC Classifications
F; F16; F16J; F16J15/00; F16J15/02; F16J15/06; F16J15/10; F16J15/102; Y; Y10; Y10T; Y10T428/00; Y10T428/30
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
65 words
A method of making a gasket from exfoliated graphite, including the steps of: (a) coating the gasket with a finely powdered exfoliated graphite release agent followed by (b) pressing the coating with pressure sufficient to bond the release agent into the surface of the gasket, and simultaneously embossing the coated gasket to form a pattern of relatively raised regions surrounded by predominantly interconnected depressed regions.
Claim 2
Independent Claim
65 words
A method of making a gasket from exfoliated graphite, including the steps of: (a) coating the gasket with a finely powdered exfoliated graphite release agent followed by (b) pressing the coating with pressure sufficient to bond the release agent into the surface of the gasket, and simultaneously embossing the coated gasket to form a pattern of relatively raised regions surrounded by predominantly interconnected depressed regions.
Claim 3
Dependent Claim
15 words
The method of claim 1 wherein the pressing step comprises calendering or pressing between platens.
Claim 4
Dependent Claim
15 words
The method of claim 1 wherein the pressing step is carried out at ambient temperature.
Claim 5
Dependent Claim
32 words
The method of claim 1, wherein a preliminary pressing step is applied to a relatively low density graphite preform so as to reduce the void content hereof prior to the coating step.
Claim 6
Dependent Claim
16 words
The method of claim 4 wherein the preliminary pressing step comprises calendering or pressing between platens.
Claim 7
Dependent Claim
25 words
The method of claim 1 wherein the embossing is carried out by pressing the graphite against a woven fabric or against an expanded metal mesh.
Claim 8
Dependent Claim
20 words
The method of claim 1 wherein the embossing is carried out by pressing the graphite against a woven monofilament cloth.
Claim 9
Dependent Claim
20 words
The method of claim 1 wherein the embossing step is carried out by means of embossing rollers or press platens.
Claim 10
Dependent Claim
14 words
The method of claim 1 wherein the release agent is amorphous graphite or talc.
Claim 11
Dependent Claim
10 words
A graphite gasket made by the method of claim 1.
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) | 1991-12-20 | 1992-06-20 | 1992-12-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-12-20 | 1996-06-20 | 1996-12-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-12-20 | 2000-06-20 | 2000-12-20 | $7700.00 | Window Closed / Lapsed |