Patent US3890109A successfully refreshed from Google Patents.
US3890109A
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Razor blades having high purity Al{hd 2{b O{HD 3 {B coating
Assignee: Wilkinson Sword Ltd
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Filing: 1973-04-06
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Granted: 1975-06-17
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Expires: 1993-04-06
Abstract
Abstract This invention relates to razor blades and methods of manufacture thereof. The invention provides razor blades having an alumina coating on and/or adjacent a cutting edge of the blades. The alumina contains at the most low concentrations of impurities and thereby improves the shaving properties of razor blades since, for example, coatings of polymers which improve the shaving properties of razor blades generally adhere well to the alumina coatings. The coatings can be deposited by sputtering from an alumina source or reactive deposition from an aluminium source in an atmosphere containing oxygen.
Inventors
- 👤 Frederick O Jones
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 10:15
CPC Classifications
B; B26; B26B; B26B21/00; B26B21/54; B26B21/58; B26B21/60; Y; Y10; Y10S; Y10S428/00; Y10S428/922; Y10S428/923; Y10S428/924; Y10S428/925; Y10T; Y10T428/00; Y10T428/12; Y10T428/12493; Y10T428/12535; Y10T428/12556; Y10T428/12569; Y10T428/12611; Y10T428/12771; Y10T428/12806; Y10T428/12826; Y10T428/12847; Y10T428/31504; Y10T428/3154; Y10T428/31678; Y10T428/31692; Y10T428/31699; Y10T428/31855; Y10T428/31909; Y10T428/31935
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
26 words
A RAZOR BLADE HAVING AN ALUMINA COATING ON AND/OR ADJACENT A CUTTING EDGE THEREOF, THE ALUMINA CONTAINING LESS THAN 3 X 10-3 ATOMIC PERCENT OF IMPURITIES.
Claim 2
Dependent Claim
26 words
A RAZOR BLADE HAVING AN ALUMINA COATING ON AND/OR ADJACENT A CUTTING EDGE THEREOF, THE ALUMINA CONTAINING LESS THAN 3 X 10-3 ATOMIC PERCENT OF IMPURITIES.
Claim 3
Dependent Claim
24 words
A razor blade according to claim 1, wherein the alumina coating contains less than 3 X 10 3 atomic percent of mono-valent metal impurities.
Claim 4
Dependent Claim
24 words
A razor blade according to claim 1, wherein the alumina coating contains less than 3 X 10 3 atomic percent of di-valent metal impurities.
Claim 5
Dependent Claim
23 words
A razor blade according to claim 2, wherein the alumina contains less than 3 X 10 3 atomic percent of alkali metal impurities.
Claim 6
Dependent Claim
21 words
A razor blade according to claim 4, wherein the alumina contains less than 1 X 10 3 atomic percent of impurities.
Claim 7
Dependent Claim
15 words
A razor blade according to claim 1, wherein the alumina is at least 99.7% pure.
Claim 8
Dependent Claim
15 words
A razor blade according to claim 6, wherein the alumina is at least 99.9% pure.
Claim 9
Dependent Claim
31 words
A razor blade according to claim 1, wherein the blade has a plurality of coatings other than a polymer coating thereon and the alumina coating is the outer of said plurality.
Claim 10
Dependent Claim
22 words
A razor blade according to claim 8, wherein the alumina coating is on a coating of a metal or of an alloy.
Claim 11
Dependent Claim
27 words
A razor blade according to claim 8, wherein said plurality of coatings other than a polymer coating have a total thickness of not more than 500 Angstroms.
Claim 12
Dependent Claim
24 words
A razor blade according to claim 10, wherein each of the coatings forming said plurality of coatings is from 50 to 450 Angstroms thick.
Claim 13
Dependent Claim
15 words
A razor blade according to claim 1, having a polymer coating on the alumina coating.
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) | 1978-06-16 | 1978-12-16 | 1979-06-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-06-16 | 1982-12-16 | 1983-06-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-06-16 | 1986-12-16 | 1987-06-17 | $7700.00 | Window Closed / Lapsed |