Thin film coating of blades

Abstract

The present invention relates to a process for forming a razor blade. The process includes the steps of: a) providing a substrate, b) forming a wedge-shaped sharpened edge on the substrate that has an included angle of less than thirty degrees and a tip radius of less than 1,000 angstroms, c) placing the substrate in a vacuum chamber, d) placing a first solid target in the vacuum chamber, e) providing a gas to be ionized in the vacuum chamber, and f) generating ions from the first solid target by applying a negative voltage to the first solid target in pulses, the ions forming a thin film coating on the wedge-shaped sharpened edge on the substrate.

1 . A process for forming a razor blade comprising the steps of:
 a) providing a substrate;   b) forming a wedge-shaped sharpened edge on said substrate that has an included angle of less than thirty degrees and a tip radius of less than 1,000 angstroms;   c) placing said substrate in a vacuum chamber;   d) placing a first solid target in said vacuum chamber;   e) providing a gas to be ionized in said vacuum chamber;   f) generating ions from said first solid target by applying a negative voltage to said first solid target in pulses, said ions forming a thin film coating on the wedge-shaped sharpened edge on the substrate; and   g) generating additional ions from said first solid target by applying a second lower negative voltage to said first solid target in pulses, said ions forming a thin film coating on the wedge-shaped sharpened edge on the substrate.   
     
     
         2 . The process of  claim 1  further comprising the step of:
 h) pivoting said substrate about an axis during step f). 
 
     
     
         3 . The process of  claim 1  further comprising the steps of:
 h) placing a second solid target in said vacuum chamber; 
 i) generating ions from said second solid target by applying a negative voltage to said second solid target in pulses, said ions forming a thin film coating on the wedge-shaped sharpened edge on the substrate. 
 
     
     
         4 . The process of  claim 3  wherein said second solid target is placed in a different position relative to said substrate than said first solid target. 
     
     
         5 . The process of  claim 1  wherein the pulses of step f) are provided in such a way that a power density is developed in a pulse in the range of 0.1 kW/cm 2  to 20 kW/cm 2 . 
     
     
         6 . The process of  claim 1  wherein the pulses of step f) are generated to have a peak ion current density on the target in the range of 0.01 to 0.5 A/cm 2 . 
     
     
         7 . The process of  claim 1  wherein the substrate is biased in the range of −20 V to −1000 V. 
     
     
         8 . The process of  claim 1  wherein said ions from said first solid target has an ion fraction reaching about 15%. 
     
     
         9 . The process of  claim 8  wherein said ion fraction reaches about 30%. 
     
     
         10 . The process of  claim 1  wherein a portion of said ions of said first solid target are doubly-ionized. 
     
     
         11 . A process for forming a razor blade comprising the steps of:
 a) providing a substrate;   b) forming a wedge-shaped sharpened edge on said substrate that has an included angle of less than thirty degrees and a tip radius of less than 1,000 angstroms;   c) placing said substrate in a vacuum chamber;   d) placing a first solid target in said vacuum chamber;   e) providing a gas to be ionized in said vacuum chamber; and   f) generating ions from said first solid target by applying a negative voltage to said first solid target in pulses, said ions forming a thin film coating on the wedge-shaped sharpened edge on the substrate, wherein a power density of each of the pulses is in the range of about 0.1 kW/cm 2  to about 20 kW/cm 2 .   
     
     
         12 . The process of  claim 11  further comprising the step of:
 g) generating additional ions from said first solid target by applying a second lower negative voltage to said first solid target in pulses, said ions forming a thin film coating on the wedge-shaped sharpened edge on the substrate. 
 
     
     
         13 . The process of  claim 11  further comprising the step of:
 g) pivoting said substrate about an axis during step f). 
 
     
     
         14 . The process of  claim 11  further comprising the steps of:
 g) placing a second solid target in said vacuum chamber; 
 h) generating ions from said second solid target by applying a negative voltage to said second solid target in pulses, said ions forming a thin film coating on the wedge-shaped sharpened edge on the substrate. 
 
     
     
         15 . The process of  claim 14  wherein said second solid target is placed in a different position relative to said substrate than said first solid target. 
     
     
         16 . The process of  claim 11  wherein the pulses of step f) are generated to have a peak ion current density on the target in the range of 0.01 to 0.5 A/cm 2 . 
     
     
         17 . The process of  claim 11  wherein the substrate is biased in the range of −20 V to −1000 V. 
     
     
         18 . The process of  claim 11  wherein said ions from said first solid target has an ion fraction reaching about 15%. 
     
     
         19 . The process of  claim 18  wherein said ion fraction reaches about 30%. 
     
     
         20 . The process of  claim 11  wherein a portion of said ions of said first solid target are doubly-ionized.