Method of making a bent razor blade

Abstract

A method for making a bent razor blade is disclosed. The method includes: providing an elongated strip of stainless steel that can be 0.076 mm thick; hardening the strip; providing a cutting edge along an edge of the strip and providing coating(s) on the cutting edge. The stainless steel has a carbon content less than 0.60% and preferably between 0.45% and 0.55% by weight. The strip is separated lengthwise into discrete razor blades. The bent portion of the razor blade is then formed using a swivel bending process.

What is claimed is: 
     
         1 . A method of making a razor blade having a bent portion, comprising the steps of:
 a) providing an elongated strip of stainless steel having a front edge portion and a back edge portion, the stainless steel having a carbon content less than 0.60% by weight;   b) hardening the strip to a first hardness;   c) providing a cutting edge extending along the front edge portion of the elongated strip;   d) cutting a lengthwise extending portion from the strip, the lengthwise extending portion providing the discrete razor blade having a length suitable for use in a razor cartridge housing, each discrete razor blade including a cutting edge, a back edge portion and a body portion therebetween; and   e) forming a region of the body portion to provide the bent portion in the body portion; wherein the forming step includes applying an arcuate surface of a nose of an apparatus to provide the bent portion to a surface of the body portion with a predetermined contact pressure and pivoting the nose about a nose axis such that the arcuate surface rolls on, without sliding relative thereto, the surface of the body portion; and   wherein the razor blade thus formed includes a first generally planar portion between the cutting edge and the bent portion and a second generally planar portion between the bent portion and the back edge portion.   
     
     
         2 . The method of  claim 1 , wherein the method further includes a step of perforating one or more apertures. 
     
     
         3 . The method of  claim 2 , wherein the step of perforation occurs before step e) and after step d). 
     
     
         4 . The method of  claim 1 , wherein the carbon content is between 0.45% and 0.55% carbon by weight. 
     
     
         5 . The method of  claim 1 , wherein the stainless steel further includes between 1.0 and 1.6% molybdenum by weight. 
     
     
         6 . The method of  claim 1 , wherein the first hardness is in a range 660 HV to 850 HV. 
     
     
         7 . The method of  claim 1 , wherein the method further includes a step of annealing at least a portion of the strip containing the cutting edge to reduce the hardness of the portion of the strip containing the cutting edge to a second hardness of at least 600 HV. 
     
     
         8 . The method of  claim 7 , wherein the step of annealing the portion of the strip containing the cutting edge occurs during a curing process for a PTFE coating applied to the cutting edge.