IP Library Granted Patent US 9,079,321
Granted Patent B2
US 9,079,321 · App. 12/174,058 · Granted Jul 14, 2015

Razor blades

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Quick Facts
Patent No.
US 9,079,321
App. No.
12/174,058
Granted
Jul 14, 2015
Kind
B2
Abstract

A razor blade having a substrate with a cutting edge being defined by a sharpened tip. The substrate has a thickness of between about 1.3 and 1.6 micrometers measured at a distance of four micrometers from the blade tip, a thickness of between about 2.2 and 2.7 micrometers measured at a distance of eight micrometers from the blade tip, a thickness of between about 3.8 and 4.9 micrometers measured at a distance of sixteen micrometers from the blade tip, a ratio of thickness measured at four micrometers from the blade tip to the thickness measured at eight micrometers from the blade tip of at least 0.55 and a ratio of thickness measured at four micrometers from the blade tip to the thickness measured at sixteen micrometers from the blade tip of at least 0.30.

Claims (13)

1. A razor blade comprising:

a stainless steel substrate with a cutting edge being defined by a sharpened tip, said substrate having a thickness of between about 1.3 and 1.6 micrometers measured at a distance of four micrometers from the blade tip, a thickness of between about 2.2 and 2.7 micrometers measured at a distance of eight micrometers from the blade tip, a thickness of between about 3.8 and 4.9 micrometers measured at a distance of sixteen micrometers from the blade tip, a ratio of thickness measured at four micrometers to the thickness measured at eight micrometers of at least 0.55 and a ratio of thickness measured at four micrometers to the thickness measured at sixteen micrometers of at least 0.30.

2. The razor blade of claim 1 , wherein the substrate is a martensitic stainless steel having a carbide density of at least about 200 carbides or more per 100 square micrometers as determined by optical microscopic cross-section.

3. The razor blade of claim 1 , wherein the substrate has a tip radius of from about 125 to 300 angstroms.

4. The razor blade of claim 1 further comprising an interlayer joined to said substrate.

5. The razor blade of claim 3 wherein said interlayer comprises niobium.

6. The razor blade of claim 3 , further comprising a coating layer joined to said interlayer.

7. The razor blade of claim 5 wherein said coating layer comprises an amorphous material containing carbon.

8. The razor blade of claim 5 further comprising an overcoat layer joined to said coating layer.

9. The razor blade of claim 7 wherein said overcoat layer comprises chromium.

10. The razor blade of claim 7 further comprising an outer layer joined to said overcoat layer.

11. The razor blade of claim 9 wherein said outer layer comprises a polymer.

12. The razor blade of claim 9 wherein said outer layer comprises polytetrafluoroethylene.

Assignments (1)
MERGER AND CHANGE OF NAME Recorded Sep 26, 2016
From: THE GILLETTE COMPANY; THE GILLETTE COMPANY LLC
To: THE GILLETTE COMPANY LLC
Reel/Frame 040145/0258 →