THIN FILM COATING OF BLADES
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.