Process of forming a razor blade
View Patent ↗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; and
f) generating ions from said first solid target by applying a negative voltage to said first solid target in pulses such that said ions from said first solid target has an ion fraction reaching about 15%, said ions forming a thin film coating on the wedge-shaped sharpened edge on the substrate.
2. The process of claim 1 wherein said first solid target is a metal, carbon or boron.
3. The process of claim 2 wherein said metal is selected from the group consisting of Al, Nb, Zr, Cr, V, Ta, Ti, W, Ni, Hf, Si, Mo and an alloy comprising any combination of elements of the group.
4. The process of claim 1 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.
5. The process of claim 1 further comprising the step of:
g) pivoting said substrate about an axis during step f).
6. The process of claim 1 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.
7. The process of claim 6 wherein said second solid target is placed in a different position relative to said substrate than said first solid target.
8. 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 .
9. The process of claim 1 wherein the pulses of step f) are provided at a pulse frequency in the range of 5 Hz to 10000 Hz.
10. The process of claim 1 wherein the pulses of step f) are generated to have a voltage in the range of −100 V to −10000 V.
11. The process of claim 1 wherein the pulses of step f) are generated to have a duration in the range of 10 μs to 10000 μs.
12. The process of claim 1 wherein the pulses of step f) are generated to have a current density on the target in the range of 0.01 to 0.5 A/cm 2 in the peak.
13. The process of claim 1 wherein the substrate is biased in the range of −20 V to −1000 V.
14. The process of claim 1 wherein the gas is an inert gas.
15. The process of claim 1 wherein the gas is a reactive gas.
16. The process of claim 1 wherein the gas is selected from the group consisting of Ar, Ne, Kr, Xe, N 2 , CR 4 , C 2 H 2 , O 2 and all combinations thereof.
17. The process of claim 1 wherein the gas is at a pressure in the range of 1 to 10 millitorr.
18. The process of claim 1 wherein said ion fraction reaches about 30%.
19. The process of claim 1 wherein a portion of said ions of said first solid target are doubly-ionized.