US3834265A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Ceramic cutting instruments
Assignee: Gillette Co LLC
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Filing: 1973-02-16
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Granted: 1974-09-10
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Expires: 1993-02-16
Abstract
Abstract The present invention is concerned with novel cutting edges and especially razor blades and microtome knives formed from sapphire and with novel processes for making cutting edges. The cutting instruments disclosed herein are characterized by having their cutting edges within 30* and preferably parallel to the C-axis (optical axis) of the sapphire. The process for preparing such cutting edges comprises forming the cutting edge blank from the sapphire in a manner such that the C-axis thereof will be parallel or at least within 30* of being parallel to the cutting edge which is to be formed and thereafter forming the cutting edges by a combination of mechanical and one or more chemical sharpening steps.
Inventors
- 👤 B Tafapolsky
- 👤 F Flaherty
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 12:08
CPC Classifications
A; A61; A61B; A61B17/00; A61B17/32; A61B17/3209; A61B17/3211; B; B26; B26B; B26B21/00; B26B21/54; B26B21/58; B26D; B26D1/00; G; G01; G01N; G01N1/00; G01N1/02; G01N1/04; G01N1/06; G01N2001/061; Y; Y10; Y10S; Y10S76/00; Y10S76/12; Y10T; Y10T83/00; Y10T83/929
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
83 words
A process for forming a sapphire cutting edge, said process comprising forming a blank from sapphire in a manner such that the edge which is to be sharpened will lie within at least 30* of being parallel to the optical axis of said sapphire and forming the cutting edge thereon by a combination of mechanical and chemical sharpening, said chemical sharpening being carried out at least subsequent to any mechanical sharpening step which causes significant deformation of the sapphire in the cutting edge.
Claim 2
Dependent Claim
83 words
A process for forming a sapphire cutting edge, said process comprising forming a blank from sapphire in a manner such that the edge which is to be sharpened will lie within at least 30* of being parallel to the optical axis of said sapphire and forming the cutting edge thereon by a combination of mechanical and chemical sharpening, said chemical sharpening being carried out at least subsequent to any mechanical sharpening step which causes significant deformation of the sapphire in the cutting edge.
Claim 3
Dependent Claim
30 words
A process as defined in claim 1 wherein the edge which is to be sharpened is at least within 25* of being parallel to the optical axis of the sapphire.
Claim 4
Dependent Claim
25 words
A process as defined in claim 1 wherein the edge whicn is to be sharpened is substantially parallel to the optical axis of the sapphire.
Claim 5
Dependent Claim
18 words
A process as defined in claim 1 wherein said chemical sharpening is carried out in hot orthophosphoric acid.
Claim 6
Dependent Claim
23 words
A process as defined in claim 4 wherein said orthophosphoric acid is heated to a temperature between about 300* F to 550* F.
Claim 7
Dependent Claim
23 words
A process as defined in claim 4 wherein said orthophosphoric acid is heated to a temperature between about 400* F to 550* F.
Claim 8
Dependent Claim
17 words
A process as defined in claim 1 wherein said cutting edge is that of a razor blade.
Claim 9
Dependent Claim
21 words
A process as defined in claim 1 wherein a metallic subcoat is applied to said cutting edge subsequent to its formation.
Claim 10
Dependent Claim
21 words
A process as defined in claim 1 wherein a polytetrafluoroethylene coating is applied to the cutting edge subsequent to its formation.
Claim 11
Dependent Claim
17 words
A process as defined in claim 8 wherein a polytetrafluoroethylene coating is applied to the metallic subcoat.
Claim 12
Dependent Claim
62 words
A sapphire cutting instrument having its cutting edge within at least 30* of being parallel to the optical axis of the sapphire and said cutting edge being formed by a combination of mechanical and chemical sharpening steps, said chemical sharpening being carried out at least subsequent to any mechanical sharpening step which causes significant deformation of the sapphire in the cutting edge.
Claim 13
Dependent Claim
62 words
A sapphire cutting instrument having its cutting edge within at least 30* of being parallel to the optical axis of the sapphire and said cutting edge being formed by a combination of mechanical and chemical sharpening steps, said chemical sharpening being carried out at least subsequent to any mechanical sharpening step which causes significant deformation of the sapphire in the cutting edge.
Claim 14
Dependent Claim
14 words
A sapphire cutting instrument as defined in claim 11 which is a razor blade.
Claim 15
Dependent Claim
22 words
A cutting instrument as defined in claim 11 wherein said cutting edge is substantially parallel to the optical axis of the sapphire.
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) | 1977-09-09 | 1978-03-11 | 1978-09-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-09-09 | 1982-03-11 | 1982-09-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-09-09 | 1986-03-11 | 1986-09-10 | $7700.00 | Window Closed / Lapsed |