Razor blade technology

Claim 2

A process for forming a razor blade comprising the steps of providing a ceramic substrate, mechanically abrading said ceramic substrate in a sequence of rough-honing and finish-honing steps with diamond abrasive materials to form a sharpened edge thereon with facets that have an included angle of less than thirty degrees and a tip radius of less than twelve hundred angstroms; and sputter-sharpened said edge to form a cutting edge defined by supplemental facets that are less than one micrometer in width and have an included angle greater than forty degrees.

Claim 3

The process of claim 1 wherein said ceramic substrate material is selected from the group consisting of silicon carbide, silicon nitride, zirconia, and alumina.

Claim 4

The process of claim 1 wherein said ceramic substrate has a bend strength in excess of 300 MPa.

Claim 5

The process of claim 3 wherein said ceramic substrate is of single crystal material and has a bend strength in excess of 700 MPa.

Claim 6

The process of claim 5 wherein said rough-honing step forms facets that have an included angle of less than twenty degrees.

Claim 7

The process of claim 1 wherein said step of mechanically abrading said ceramic substrate forms a sharpened edge thereon that has an ultimate tip radius in the range of 600 to 800 angstroms.

Claim 8

A process for forming a razor blade comprising the steps of providing a ceramic substrate, mechanically abrading said ceramic substrate to form a sharpened edge thereon with facets that have an included angle of less than thirty degrees and a tip radius of less than twelve hundred angstroms; sputter-sharpening said edge to form a cutting edge defined by supplemental facets that are less than one micrometer in width and have an included angle greater than forty degrees; sputter depositing a chromium-containing metal layer on said cutting edge; and then applying an adherent polymer coating on said metal coated cutting edge.

Claim 9

A process for forming a razor blade comprising the steps of providing a ceramic substrate, mechanically abrading said ceramic substrate to form a sharpened edge thereon with facets that have an included angle of less than thirty degrees and a tip radius of less than twelve hundred angstroms; sputter-sharpening said edge to form a cutting edge defined by supplemental facets that are less than one micrometer in width and have an included angle greater than forty degrees; sputter depositing a chromium-containing metal layer on said cutting edge; and then applying an adherent polymer coating on said metal coated cutting edge.

Claim 10

The process of claim 7 wherein said sputter-deposited metal layer on said cutting edge has a thickness of less than five hundred angstroms, and said adherent polymer coating on said metal coated cutting edge has a thickness of less than ten micrometers.

Claim 11

A process for forming a razor blade comprising the steps of providing a ceramic substrate, mechanically abrading said ceramic substrate to form a sharpened edge thereon with facets that have an included angle of less than thirty degrees and a tip radius of less than twelve hundred angstroms; and sputter-sharpening said edge to form a cutting edge defined by supplemental facets that are less than one micrometer in width and have an included angle greater than forty degrees, the sputter-sharpened surfaces immediately adjacent said cutting edge having widths in the range of 0.1-0.5 micrometer, an effective included angle substantially greater than the included angle of said mechanically-abraded facets, and providing a tip radius of less than five hundred angstroms.

Claim 12

A process for forming a razor blade comprising the steps of providing a ceramic substrate, mechanically abrading said ceramic substrate to form a sharpened edge thereon with facets that have an included angle of less than thirty degrees and a tip radius of less than twelve hundred angstroms; and sputter-sharpening said edge to form a cutting edge defined by supplemental facets that are less than one micrometer in width and have an included angle greater than forty degrees, the sputter-sharpened surfaces immediately adjacent said cutting edge having widths in the range of 0.1-0.5 micrometer, an effective included angle substantially greater than the included angle of said mechanically-abraded facets, and providing a tip radius of less than five hundred angstroms.

Claim 13

The process of claim 9 wherein said ceramic substrate material is selected from the group consisting of alumina and zirconia.

Claim 14

The process of claim 1 and further including the step of annealing said mechanically-abraded ceramic substrate to modify the ultimate tip region and reduce subsurface defects and surface irregularities adjacent said sharpened edge.

Claim 15

The process of claim 11 wherein said ceramic substrate material is selected from the group consisting of silicon carbide, silicon nitride, zirconia, and alumina.

Claim 16

The process of claim 11 wherein said ceramic substrate is of single crystal material and has a bend strength in excess of 700 MPa.

Claim 17

A process for forming a razor blade comprising the steps of providing a ceramic substrate, mechanically abrading said ceramic substrate to form a sharpened edge thereon with facets that have an included angle of less than thirty degrees and a tip radius of less than twelve hundred angstroms; said step of mechanically abrading said ceramic substrate including a rough-honing step that form facets that have an included angle of less than twenty degrees and a finish-honing step that forms a sharpened edge that has an ultimate tip radius in the range of 600 to 800 angstroms, annealing said mechanically-abraded ceramic substrate to modify the ultimate tip region and reduce subsurface defects and surface irregularities adjacent said sharpened edge; and sputter-sharpening said edge to form a cutting edge defined by supplemental facets that are less than one micrometer in width and have an included angle greater than forty degrees.

Claim 18

A process for forming a razor blade comprising the steps of providing a ceramic substrate, mechanically abrading said ceramic substrate to form a sharpened edge thereon with facets that have an included angle of less than thirty degrees and a tip radius of less than twelve hundred angstroms; said step of mechanically abrading said ceramic substrate including a rough-honing step that form facets that have an included angle of less than twenty degrees and a finish-honing step that forms a sharpened edge that has an ultimate tip radius in the range of 600 to 800 angstroms, annealing said mechanically-abraded ceramic substrate to modify the ultimate tip region and reduce subsurface defects and surface irregularities adjacent said sharpened edge; and sputter-sharpening said edge to form a cutting edge defined by supplemental facets that are less than one micrometer in width and have an included angle greater than forty degrees.

Claim 19

The process of claim 11 wherein said ceramic substrate material is single crystal material selected from the group consisting of alumina and zirconia that has a bend strength in excess of 700 MPa, said ceramic substrate is mechanically abraded in a sequence of rough-honing and finish-honing steps with diamond abrasive material with grain size of less than twenty micrometers and further including the steps of sputter depositing a metallic layer on said cutting edge to a thickness of less than five hundred angstroms, and then applying an adherent polymer coating on said metal coated cutting edge to a thickness of less than ten micrometers.

Claim 20

The process of claim 11 wherein said annealing is at a temperature of at least 1000° C.

Claim 21

A razor blade comprising a ceramic substrate with mechanically-abraded facets that have a width of at least about 0.1 millimeter and an included angle of less than thirty degrees, a sputter-sharpened cutting edge of tip radius less than about five hundred angstroms that is defined by supplemental sputter-sharpened facets that have an effective included angle substantially greater than the included angle of said mechanically abraded facets, a sputter-deposited metal layer on said sputter-etched cutting edge, and an adherent polymer coating on said metal coated cutting edge.

Claim 22

A razor blade comprising a ceramic substrate with mechanically-abraded facets that have a width of at least about 0.1 millimeter and an included angle of less than thirty degrees, a sputter-sharpened cutting edge of tip radius less than about five hundred angstroms that is defined by supplemental sputter-sharpened facets that have an effective included angle substantially greater than the included angle of said mechanically abraded facets, a sputter-deposited metal layer on said sputter-etched cutting edge, and an adherent polymer coating on said metal coated cutting edge.

Claim 23

The razor blade of claim 17 wherein said mechanically-abraded facets are thermally annealed.

Claim 24

The razor blade of claim 17 wherein said sputter-sharpened surfaces immediately adjacent said cutting edge have widths in the range of 0.1-0.5 micrometer.

Claim 25

The razor blade of claim 17 wherein said sputter-deposited metal layer on said sputter-sharpened cutting edge has a thickness of less than five hundred angstroms, and said adherent polymer coating on said metal coated cutting edge has a thickness of less than ten micrometers.

Claim 26

A razor blade comprising a ceramic substrate with mechanically-abraded facets that have a width of at least about 0.1 millimeter and an included angle of less than thirty degrees, and a sputter-sharpened cutting edge of tip radius less than about five hundred angstroms that is defined by supplemental sputter-sharpened facets that have an effective included angle substantially greater than the included angle of said mechanically abraded facets, said cutting edge being generally parallel to the C crystallographic axis of said substrate.

Claim 27

A razor blade comprising a ceramic substrate with mechanically-abraded facets that have a width of at least about 0.1 millimeter and an included angle of less than thirty degrees, and a sputter-sharpened cutting edge of tip radius less than about five hundred angstroms that is defined by supplemental sputter-sharpened facets that have an effective included angle substantially greater than the included angle of said mechanically abraded facets, said cutting edge being generally parallel to the C crystallographic axis of said substrate.

Claim 28

The razor blade of claim 21 wherein said ceramic substrate material is selected from the group consisting of silicon carbide, silicon nitride, zirconia, and alumina and has a bend strength in excess of 300 MPa.

Claim 29

The razor blade of claim 22 wherein each said sputter-sharpened facet immediately adjacent said cutting edge has a width of about 0.3 micrometer and an effective included angle of at least forty degrees, and further including a sputter-deposited metal layer on said cutting edge, and an adherent polymer coating on said metal coated cutting edge, said sputter-deposited metal layer having a thickness of less than five hundred angstroms, and said adherent polymer coating on said metal layer having a thickness of less than ten micrometers.

Claim 30

The razor blade of claim 21 wherein said mechanically abraded facets are thermally annealed at a temperature of at least 1000° C.

Claim 31

A shaving unit comprising support structure that defines spaced skin-engaging surfaces, and razor blade structure secured to said support structure, said razor blade structure including a ceramic substrate with mechanically-abraded facets that have a width of at least about 0.1 millimeter and an included angle of less than thirty degrees, and a sputter-sharpened cutting edge of tip radius less than about five hundred angstroms that is defined by facets that have an effective included angle substantially greater than the included angle of said mechanically-abraded facets, a sputter-deposited metal layer on said sputter-etched cutting edge, and an adherent polymer coating on said metal coated cutting edge, said sputter-sharpened cutting edge being disposed between said skin-engaging surfaces.

Claim 32

A shaving unit comprising support structure that defines spaced skin-engaging surfaces, and razor blade structure secured to said support structure, said razor blade structure including a ceramic substrate with mechanically-abraded facets that have a width of at least about 0.1 millimeter and an included angle of less than thirty degrees, and a sputter-sharpened cutting edge of tip radius less than about five hundred angstroms that is defined by facets that have an effective included angle substantially greater than the included angle of said mechanically-abraded facets, a sputter-deposited metal layer on said sputter-etched cutting edge, and an adherent polymer coating on said metal coated cutting edge, said sputter-sharpened cutting edge being disposed between said skin-engaging surfaces.

Claim 33

The shaving unit of claim 25 wherein said razor blade structure includes two ceramic substrates, and each said ceramic substrate has a sputter-sharpened cutting edge of tip radius less than about five hundred angstroms that is defined by facets that have an effective included angle substantially greater than the included angle of said mechanically-abraded facets, said sputter-sharpened cutting edges being disposed parallel to one another between said skin engaging surfaces.

Claim 34

The shaving unit of claim 25 wherein said sputter-sharpened surfaces immediately adjacent said cutting edge have widths in the range of 0.1-0.5 micrometer.

Claim 35

The razor blade of claim 25 wherein said mechanically-abraded facets are thermally annealed.

Claim 36

The shaving unit of claim 28 wherein said razor blade structure includes two ceramic substrates, and each said ceramic substrate has a sputter-sharpened cutting edge of tip radius less than about five hundred angstroms that is defined by facets that have an effective included angle substantially greater than the included angle of said mechanically abraded facets, said sputter-sharpened cutting edges being disposed parallel to one another between said skin-engaging surfaces.

Claim 37

The shaving unit of claim 29 wherein said ceramic substrate material is selected from the group consisting of silicon carbide, silicon nitride, zirconia, and alumina and has a bend strength in excess of 700 MPa.

Claim 38

A shaving unit comprising support structure that defines spaced skin-engaging surfaces, and razor blade structure secured to said support structure, said razor blade structure including two ceramic substrates of material selected from the group consisting of silicon carbide, silicon nitride, zirconia, and alumina and having a bend strength in excess of 700 MPa, each said substrate having thermally annealed mechanically-abraded facets that have a width of at least about 0.1 millimeter and an included angle of less than thirty degrees, and a sputter-sharpened cutting edge of tip radius less than about five hundred angstroms that is defined by facets that have an effective included angle substantially greater than the included angle of said mechanically-abraded facets, each said sputter-sharpened facet immediately adjacent said cutting edge having a width of about 0.3 micrometer and said sputter-sharpened facets having an effective included angle of at least forty degrees, a sputter-deposited metal layer of thickness less than five hundred angstroms on each said cutting edge, and an adherent polymer coating of thickness of less than ten micrometers on each said metal layer, said sputter-sharpened cutting edge being disposed between said skin-engaging surfaces.

Claim 39

A shaving unit comprising support structure that defines spaced skin-engaging surfaces, and razor blade structure secured to said support structure, said razor blade structure including two ceramic substrates of material selected from the group consisting of silicon carbide, silicon nitride, zirconia, and alumina and having a bend strength in excess of 700 MPa, each said substrate having thermally annealed mechanically-abraded facets that have a width of at least about 0.1 millimeter and an included angle of less than thirty degrees, and a sputter-sharpened cutting edge of tip radius less than about five hundred angstroms that is defined by facets that have an effective included angle substantially greater than the included angle of said mechanically-abraded facets, each said sputter-sharpened facet immediately adjacent said cutting edge having a width of about 0.3 micrometer and said sputter-sharpened facets having an effective included angle of at least forty degrees, a sputter-deposited metal layer of thickness less than five hundred angstroms on each said cutting edge, and an adherent polymer coating of thickness of less than ten micrometers on each said metal layer, said sputter-sharpened cutting edge being disposed between said skin-engaging surfaces.