Razor blade coating

Abstract

A razor blade that includes a substrate with a cutting edge, the substrate includes (a) a thin-film of a first material disposed thereon, the thin-film having a thickness less than 1 μm; (b) a mixed nitride-thin-film interregion disposed at or adjacent a surface of the thin-film and a surface of the substrate; and (c) a nitride region disposed adjacent the mixed nitride-thin-film interregion.

What is claimed is: 
     
         1 . A method for coating a razor blade comprising the steps of:
 (a) providing a substrate comprising a cutting edge;   (b) applying a thin-film of a first material on the substrate by a thin-film process, wherein the thin-film has a thickness less than 1 μm after being applied;   (c) nitriding the thin-film and the substrate with a nitrogen-containing gas or plasma to form:   1) a mixed nitride-thin-film interregion disposed at and adjacent a surface of the thin film and a surface of the substrate, and
 2) a nitride region disposed adjacent the mixed nitride-thin-film interregion. 
   
     
     
         2 . The method of  claim 1  wherein step (c) further forms a mixed nitride-substrate interregion disposed adjacent the mixed nitride-thin-film interregion beneath the surface of the substrate. 
     
     
         3 . The method of  claim 1  wherein the first material comprises a material selected from the group consisting of a metal, a metal alloy, a metal carbide, a metal oxide, a metal nitride, derivatives and combinations thereof. 
     
     
         4 . The method of  claim 3  wherein the metal is selected from the group consisting of Ta, Ru, Ni, V, Ti, Pt, Cr, Nb, Hf, W, Zr, Ag, Re, Pd, Fe, and combinations thereof. 
     
     
         5 . The method of  claim 1  further comprising the step of (e) applying a coating of a second material over the nitride-thin-film interregion, the nitride region, or both. 
     
     
         6 . The method of  claim 5 , wherein the second material comprises a material selected from the group consisting of a metal, a metal alloy, a metal carbide, a metal oxide, a metal nitride, diamond, amorphous diamond, diamond-like carbon, boron, boron nitride, derivatives and combinations thereof. 
     
     
         7 . The method of  claim 6  wherein the metal is selected from the group consisting of Ta, Ru, Ni, V, Ti, Pt, Cr, Nb, Hf, W, Zr, Ag, Re, Pd, Fe, and combinations thereof. 
     
     
         8 . The method of  claim 5  further comprising the step of (d) applying a fluoropolymer-containing coating over the second material coating. 
     
     
         9 . The method of  claim 1  further comprising the step of (f) applying fluoropolymer-containing coating over nitride-thin-film interregion, the nitride region, or both. 
     
     
         10 . The method of  claim 1  wherein the cutting edge comprises a wedge-shaped tip that has an included angle of less than thirty degrees and a tip radius of less than about 1,000 Angstroms.