Razor blade technology

• US 6,684,513 B1
• Filed: 02/29/2000
• Issued: 02/03/2004
• Est. Priority Date: 02/29/2000
• Status: Expired due to Term

• Current Assignee: The Gillette Company LLC (The Procter & Gamble Company)
• Original Assignee: Gillette Company (The Procter & Gamble Company)
• Inventors: Sonnenberg, Neville, Zhuk, Andrew, White, Charles, Hahn, Steve, Clipstone, Colin John
• Primary Examiner(s): PAYER, HWEI SIU CHOU
• Application Number:
  US09/515,421
• Time in Patent Office: 1,435 Days
• Field of Search: 30/50, 303/465.3, 303/465.4, 303/465.5, 303/46, 76D/IG.8
• US Class Current: 30/346.54
• CPC Class Codes: B26B 21/60 by the coating material

Abstract

A razor blade including a substrate with a cutting edge defined by a sharpened tip and adjacent facets, a layer of hard coating on the cutting edge, an overcoat layer of a chromium containing material on the layer of hard carbon coating, and an outer layer of polytetrafluoroethylene coating over the overcoat layer.

Claims

1. A razor blade comprising a substrate with a cutting edge defined by a sharpened tip and adjacent facets,

a layer of hard coating on said cutting edge, said hard coating being made of amorphous material containing carbon,

an overcoat layer of a chromium containing material on said layer of hard coating, and

an outer layer of polytetrafluoroethylene coating over said overcoat layer.

2. The blade of claim 1 wherein said hard carbon coating comprises diamond-like carbon material.

3. The blade of claim 2 wherein said overcoat layer consists of chromium.

4. The blade of claim 3 wherein said polytetrafluoroethylene is Krytox LW1200.

5. The blade of claim 2 further comprising a niobium interlayer between said substrate and said hard coating.

6. The blade of claim 1 wherein said hard carbon coating comprises amorphous diamond material.

7. The blade of claim 1 wherein said overcoat layer consists of chromium.

8. The blade of claim 1 wherein said overcoat layer consists of a chromium containing alloy compatible with polytetrafluoroethylene.

9. The blade of claim 8 wherein said alloy is a chromium platinum alloy.

10. The blade of claim 7, 8, 3, or 9 wherein said overcoat layer is compressively stressed.

11. The blade of claim 1 further comprising an interlayer between said substrate and said layer of hard coating.

12. The blade of claim 11 wherein said interlayer comprises niobium.

13. The blade of claim 11 wherein said interlayer comprises a chromium containing material.

14. The blade of claim 1 wherein said polytetrafluoroethylene is Krytox LW1200.

15. The blade of claim 1 wherein said hard coating layer has a thickness less than 2,000 angstroms.

16. The blade of claim 1 wherein said overcoat layer is between 100 and 500 angstroms thick.

17. The blade of claim 1 wherein said outer layer is between 100 and 5,000 angstroms thick.

18. The blade of claim 1, 3, 4 or 15 wherein said cutting edge has less rounding with repeated shaves than it would have without said overcoat layer.

19. The blade of claim 1 wherein said hard coating is doped with another element.

20. A shaving razor comprising

a handle,

a housing connected to said handle, and

at least one razor blade mounted in said housing, said blade comprising

a substrate with a cutting edge defined by a sharpened tip and adjacent facets,

a layer of hard coating on said cutting edge, said hard coating being made of amorphous material containing carbon,

an overcoat layer of a chromium containing material on said layer of hard coating, and

an outer layer of polytetrafluoroethylene coating over said overcoat layer.

21. The razor of claim 20 further comprising a niobium interlayer between said substrate and said hard coating.

22. The razor of claim 20 wherein said overcoat layer consists of chromium.

23. The razor of claim 20 wherein said hard coating is doped with another element.

24. A method of making a razor blade comprising

providing a substrate with a cutting edge defined by a sharpened tip and adjacent facets,

adding a layer of hard coating on said cutting edge, said hard coating being made of amorphous material containing carbon,

adding an overcoat layer of a chromium containing material on said layer of hard coating, and

adding an outer layer of polytetrafluoroethylene coating over said overcoat layer.

25. The method of claim 24 wherein said adding a layer of hard coating includes vapor depositing a carbon containing material.

26. The method of claim 24 wherein said adding a layer of chromium containing material includes vapor depositing said chromium containing material.

27. The method of claim 26 wherein said adding a layer of chromium containing material includes sputter depositing under conditions to result in compressively stressed material.

28. A razor blade comprising

a substrate with a cutting edge defined by a sharpened tip and adjacent facets;

a layer of a hard carbon containing material, doped with another element, on the cutting edge;

an overcoat layer of a chromium containing material on the layer of the hard carbon containing material; and

an outer layer of polytetrafluoroethylene over the overcoat layer.

29. The razor blade of claim 28, wherein the element is a metal.

30. The razor blade of claim 29, wherein the metal is selected from the group consisting of tungsten and titanium.

31. The razor blade of claim 29, wherein the metal is chromium.

32. The razor blade of claim 31, wherein the hard carbon containing material is diamond-like carbon.

33. The razor blade of claim 28, wherein the hard carbon containing material is selected from the group consisting of diamond-like carbon and amphorous diamond.

34. The razor blade of claim 28, wherein the layer of hard carbon material has a thickness less than 2,000 angstroms, the overcoat layer has a thickness between 100 and 500 angstroms, and the outer layer has a thickness between 100 and 5,000 angstroms.

35. A shaving razor comprising

a handle,

a housing connected to the handle, and

at least one razor blade within the housing, the razor blade comprising

a substrate with a cutting edge defined by a sharpened tip and adjacent facets;

a layer of a hard carbon containing material, doped with another element, on the cutting edge;

an overcoat layer of a chromium containing material on the layer of the hard carbon containing material; and

an outer layer of polytetrafluoroethylene over the overcoat layer.

36. The shaving razor of claim 35, wherein the element is a metal.

37. The shaving razor of claim 35, wherein the metal is chromium.

38. The shaving razor of claim 35, wherein the hard carbon containing material is selected from the group consisting of diamond-like carbon and amphorous diamond.