Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B26—HAND CUTTING TOOLS; CUTTING; SEVERING
  • B26B—HAND-HELD CUTTING TOOLS NOT OTHERWISE PROVIDED FOR
  • B26B21/00—Razors of the open or knife type; Safety razors or other shaving implements of the planing type; Hair-trimming devices involving a razor-blade; Equipment therefor
  • B26B21/54—Razor-blades
  • B26B21/58—Razor-blades characterised by the material
  • B26B21/60—Razor-blades characterised by the material by the coating material

Definitions

• This invention relates to improved razors and razor blades and to processes for producing razor blades or similar cutting tools with sharp and durable cutting edges.
• a razor blade typically is formed of suitable substrate material such as metal or ceramic and an edge is formed with wedge-shape configuration with 'an ultimate edge or tip that has a radius of less than about 1,000 angstroms, the wedge shaped surfaces having an included angle of less than 30'.
• suitable substrate material such as metal or ceramic
• the wedge shaped surfaces having an included angle of less than 30'.
• supplemental coating material has been proposed for shave facilitation, and/or to increase the hardness and/or corrosion resistance of the shaving edge.
• a number of such coating materials have been proposed, such as polymeric materials and metals, as well as other materials including diamond and diamond-like carbon (DLC) material.
• Each such layer or layers of supplemental material must have adhesion compatibility so that each layer remains firmly adhered to the substrate throughout the useful life of the razor blade, and desirably provide characteristics such as improved shavability, improved hardness and/or corrosion resistance while not adversely affecting the geometry and cutting effectiveness of the shaving edge. It has been proposed to provide the cutting edges of razor blades with improved mechanical properties by applying to the sharpened edge of the substrate a coating of diamond or diamond-like carbon (DLC) material. Such materials may be characterized as having substantial sp3 carbon bonding; a mass density greater than 1.5 grams/cm 3 ; and a Raman peak at about 1331 cm -1 (diamond) or about 1552 cm" 1 (DLC) .
• DLC diamond-like carbon
• a razor blade comprising a substrate with a wedge-shaped edge, an interlayer of material selected from the group consisting of molybdenum, nickel, niobium, silicon, silicon carbide, tantalum, vanadium, and alloys of such materials on the tip and flanks of the wedge-shaped edge, the thickness of the interlayer preferably being in the range of about 50-500 angstroms, and a layer of diamond or diamond-like carbon material on the interlayer that preferably has a thickness of at least about 1200 angstroms, defines a tip radius of less than about 400 angstroms and an aspect ratio in the range of 1:1-3:1.
• the blade exhibits excellent shaving properties and long shaving life.
• the razor blade substrate is steel; the diamond or DLC coating is at least twice as hard as the metal substrate; the wedge- shaped edge is formed by a sequence of mechanical abrading steps; and the layers of interlayer material (a preferred material being niobium) and diamond or diamond-like carbon material are formed by sputtering material from targets of the interlayer material and graphite.
• a process for forming a razor blade that includes the steps of providing a substrate, forming on an edge of the substrate a wedge- shaped sharpened edge that has an included angle of less than 30* and a tip radius (i.e.
• the interlayer and the diamond or DLC layer may be deposited by various techniques such as plasma decomposition of hydrocarbon gases, sputter deposition using ions from either a plasma or an ion gun to bombard a target, directly using a beam of carbon ions, and ion beam assisted deposition (IBAD) process using either E-Beam or sputtering sources.
• plasma decomposition of hydrocarbon gases sputter deposition using ions from either a plasma or an ion gun to bombard a target, directly using a beam of carbon ions
• IBAD ion beam assisted deposition
• the substrate is mechanically abraded in a sequence of honing steps to form the sharpened edge; layers of niobium and diamond or diamond-like carbon material are successively deposited by sputtering; the niobium interlayer having a thickness of less than about five hundred angstroms, and the diamond or DLC coating on the niobium coated cutting edge having a thickness of at least about twelve hundred angstroms; the layer of diamond having a Raman peak at about 1331 cm"" 1 and the layer of diamond ⁇ like carbon (DLC) material having a Raman peak at about 1550 cm" *1 ; substantial sp3 carbon bonding; and a mass density greater than 1.5 grams/cm 3 ; and an adherent polymer coating is applied on the diamond or DLC coated cutting edge.
• layers of niobium and diamond or diamond-like carbon material are successively deposited by sputtering; the niobium interlayer having a thickness of less than about five hundred angstroms, and the diamond or D
• a shaving unit that comprises blade support structure that has external surfaces for engaging user skin ahead and rearwardly of the blade edge or edges and at least one blade member secured to the support structure.
• the razor blade structure secured to the support structure includes a substrate with a wedge-shaped cutting edge defined by facets that have an included angle of less than seventeen degrees at a distance of forty micrometers from the sharpened tip, an interlayer selected from the group consisting of molybdenum, nickel, niobium, silicon, silicon carbide, tantalum, vanadium, and alloys of such materials and a layer of strengthening material on the interlayer that has a thickness of at least twelve hundred angstroms from the sharpened tip of said substrate to a distance of forty micrometers from the sharpened tip, and an ultimate tip defined by facets that have lengths of at least about 0.1 micrometer and define an included angle of at least sixty degrees, a radius at the ultimate tip of the strengthening material of less than 400 angstroms and an aspect ratio in the range of 1:1-3
• the razor blade structure includes two steel substrates, the wedge- shaped edges are disposed parallel to one another between the skin-engaging surfaces; a niobium interlayer is between the steel substrate and the edge strengthening layer and the edge strengthening layer is of diamond or DLC material; each niobium layer has a thickness of less than about five hundred angstroms; each diamond or DLC coating has a thickness of about two thousand angstroms (typically a range of 1800-2200 angstroms depending on processing parameters) and is characterized by substantial sp3 carbon bonding; a mass density greater than 1.5 grams/cm 3 ; and a Raman peak at about 1331 cm * " 1 (diamond) or about 1550 cm * " 1 (DLC) ; and an adherent polymer coating is on each layer of diamond or diamond-like carbon material.
• the shaving unit may be of the disposable cartridge type adapted for coupling to and uncoupling from a razor handle or may be integral with a handle so that the complete razor is discarded as a unit when the blade or blades become dull.
• the front and rear skin engaging surfaces cooperate with the blade edge (or edges) to define the shaving geometry.
• Particularly preferred shaving units are of the types shown in U.S. Patent 3,876,563 and in U.S. Patent 4,586,255.
• Fig. 1 is a perspective view of a shaving unit in accordance with the invention
• Fig. 2 is a perspective view of another shaving unit in accordance with the invention
• Fig. 3 is a diagrammatic view illustrating one example of razor blade edge geometry in accordance with the invention.
• Fig. 4 is a diagrammatic view of apparatus for the practice of the invention.
• Figs. 5 and 6 are Raman spectra of DLC material deposited with the apparatus of Fig. 4. Description of Particular E ⁇ nbodiments
• shaving unit 10 includes structure for attachment to a razor handle, and a platform member 12 molded of high-impact polystyrene that includes structure defining forward, transversely-extending skin engaging surface 14.
• Cap member 24 of molded high-impact polystyrene has structure defining skin-engaging surface 26 that is disposed rearwardly of blade edge 22, and affixed to cap member 24 is shaving aid composite 28.
• the shaving unit 30 shown in Fig. 2 is of the type shown in Jacobson U.S. Patent 4,586,255 and includes molded body 32 with front portion 34 and rear portion 36. Resiliently secured in body 32 are guard member 38, leading blade unit 40 and trailing blade unit 42. Each blade unit 40, 42 includes a blade member 44 that has a sharpened edge 46. A shaving aid composite 48 is fractionally secured in a recess in rear portion 36.
• FIG. 3 A diagrammatic view of the edge region of the blades 16, 20 and 44 is shown in Fig. 3.
• the blade includes stainless steel body portion 50 with a wedge- shaped sharpened edge formed in a sequence of edge forming honing operations that forms a tip portion 52 that has a radius typically less than 500 angstroms with facets 54 and 56 that diverge at an angle of about 13°.
• Deposited on tip 52 and facets 54, 56 is interlayer 58 of niobium that has a thickness of about 300 angstroms.
• niobium interlayer 58 Deposited on niobium interlayer 58 is outer layer 60 of diamond-like carbon (DLC) that has a thickness of about 2,000 angstroms, with facets 62, 64 that have lengths of about one-quarter micrometer each and define an included angle of about 80', facets 62, 64 merging with main facet surfaces 66, 68 that are disposed at an included angle of about 13* and an aspect ratio (the ratio of the distance (a) from DLC tip 70 to stainless steel tip 52 and the width (b) of the DLC coating 60 at tip 52) of about 1.7.
• DLC diamond-like carbon
• facets 62, 64 that have lengths of about one-quarter micrometer each and define an included angle of about 80'
• main facet surfaces 66, 68 merging with main facet surfaces 66, 68 that are disposed at an included angle of about 13* and an aspect ratio (the ratio of the distance (a) from DLC tip 70 to stainless steel tip 52 and the width (b) of
• FIG. 4 Apparatus for processing blades of the type shown in Fig. 3 is diagrammatically illustrated in Fig. 4.
• That apparatus includes a DC planar magnetron sputtering system manufactured by Vac Tec Systems of Boulder, Colorado that has stainless steel chamber 74 with wall structure 80, door 82 and base structure 84 in which is formed port 86 coupled to a suitable vacuum system (not shown) .
• a suitable vacuum system (not shown)
• mounteded in chamber 74 is carousel support 88 with upstanding support member 90 on which is disposed a stack of razor blades 92 with their sharpened edges 94 in alignment and facing outwardly from support 90.
• Targets 96 and 98 are vertically disposed plates, each about twelve centimeters wide and about thirty-seven centimeters long.
• Support structures 76, 78 and 88 are electrically isolated from chamber 74 and electrical connections are provided to connect blade stack 92 to RF power supply 100 through switch 102 and to DC power supply 104 through switch 106; and targets 96 and 98 are connected through switches 108, 110, respectively, to DC magnetron power supply 112.
• Shutter structures 114 and 116 are disposed adjacent targets 96, 98, respectively, for movement between an open position and a position obscuring its adjacent target.
• Carousel 88 supports the blade stack 92 with the blade edges 94 spaced about seven centimeters from the opposed target plate 96, 98 and is rotatable about a vertical axis between a first position in which blade stack 92 is in opposed alignment with niobium target 96 (Fig. 4) and a second position in which blade stack 92 is in opposed alignment with graphite target 98.
• a stack of blades 92 (five centimeters high) is secured on support 90; chamber 74 is evacuated; the targets 96, 98 are cleaned by DC sputtering for five minutes; switch 102 is then closed and the blades 92 are RF cleaned in an argon environment for five minutes at a pressure of ten millitorr, an argon flow of 200 seem and a power of 1.5 kilowatts; the argon flow is then reduced to 150 seem at a pressure of 2.0 millitorr in chamber 74; switch 106 is closed to apply a DC bias of -25 volts on blades 92; switch 108 is closed to commence sputtering at one kilowatt power and shutter 114 in front of niobium target 96 is opened for thirty seconds to deposit a niobium layer 58 of about 300 angstroms thickness on the blade edges 94.
• Shutter 114 is then closed, switches 106 and 108 are opened, and carousel 88 is rotated 90 * to juxtapose the blade edges of blade stack 92 with graphite target 98.
• Pressure in chamber 74 is maintained at two millitorr with an argon flow of 150 seem;
• switch 110 is closed to sputter graphite target 98 at 750 watts;
• switch 102 is closed to apply a 13.56 MHz RF bias of eight hundred watts (-420 volts DC self bias voltage) on blades 92, and concurrently shutter 116 is opened for twenty minutes to deposit a DLC layer 60 of about two thousand angstroms thickness on niobium layer 58.
• the DLC coating 60 had a radius at tip 70 of about 350 Angstroms that is defined by facets 62, 64 that have an included angle of about 80", and an aspect ratio of about 1.9:1.
• Raman spectroscopy of the coating material 60 deposited in this process shows a broad Raman peak 118 extending between about 1350 and 1530 cm" 1 wave numbers, a spectrum typical of DLC structure.
• a coating 72 of polytetrafluoroethylene telomer is then applied to the DLC-coated edges of the blades.
• the process involves heating the blades in a neutral atmosphere of argon and providing on the cutting edges of the blades an adherent and friction- reducing polymer coating of solid PTFE.
• Coatings 58 and 60 were firmly adherent to the blade body 50, provided low wet wool felt cutter force (the lowest of the first five cuts with wet wool felt (L5) being about 0.45 kilogram), and withstood repeated applications of wool felt cutter forces indicating that the DLC coating 60 is substantially unaffected by exposure to the severe conditions of this felt cutter test and remains firmly adhered to the blade body 50, even after immersion in 80*C. distilled water for sixteen hours.
• Resulting blade elements 44 were assembled in cartridge units 30 of the type shown in Fig. 2 and shaved with excellent shaving results.
• target 96 is molybdenum and target 98 is graphite.
• chamber 74 is evacuated; the targets 96, 98 are cleaned by DC sputtering for five minutes; the blades 92 are then RF cleaned in an argon environment at a pressure of ten millitorr at a power of 1.5 kilowatts and an argon flow of 200 seem; the argon flow reduced to 150 seem at a pressure of two millitorr in chamber 74; shutter 114 in front of molybdenum target 96 is opened, and target 96 is sputtered at one kilowatt power with a bias of -150 volts on blades 82 for twenty-two seconds to deposit a molybdenum layer 58 of about 200 angstroms thickness on the blade edges 94.
• Shutter 114 is then closed, and carousel 88 is rotated 90* to juxtapose blade stack 92 with graphite target 98.
• Pressure in chamber 74 is maintained at two millitorr with an argon flow of 150 seem, shutter 116 is opened, and graphite target 98 is sputtered at 900 watts with a bias of -150 volts on blades 92 for 10 minutes to deposit a DLC layer 60 of about 800 angstroms thickness on molybdenum layer 58.
• Raman spectroscopy of the coating material 60 deposited in this process shows a broad Raman peak 120 centered at about 1525 cm" 1 wave number, a spectrum typical of DLC structure.
• the DLC coating 60 was firmly adherent to the blade body 50 and withstood repeated applications of wool felt cutter forces, indicating that the DLC coating 60 is substantially unaffected by exposure to the severe conditions of this felt cutter test and remains firmly adhered to the blade body 50.
• Its tip 70 had a radius of about 700 angstroms and an aspect ratio of 1.7:1.
• a coating 72 of polytetrafluoroethylene telomer was then applied to the DLC-coated edges of the blades in accordance with the teaching of U.S. Patent No. 3,518,110.
• This process involves heating the blades in a neutral atmosphere such as nitrogen or argon or a reducing atmosphere such as cracked ammonia and providing on the cutting edges of the blades an adherent and friction-reducing polymer coating of solid PTFE.
• the resulting blade elements 44 were assembled in cartridge units 30 of the type shown in Fig. 2 and shaved with excellent shaving results.
• chamber 74 was evacuated; the targets 96, 98 were cleaned by DC sputtering for five minutes; the blades 82 were then RF cleaned in an argon environment at a pressure of ten millitorr at a power of 1.5 kilowatts and an argon flow of 200 seem for two minutes; the argon flow reduced to 150 seem at a pressure of two millitorr in chamber 74; shutter 114 in front of molybdenum target 96 was then opened; and target 90 was sputtered at one kilowatt power with a bias of -150 volts on blades 92 for thirty-two seconds to deposit a molybdenum layer 58 of about 300 angstroms thickness on the blade edges 94. Shutter 114 was closed and carousel 88 was rotated 90° to juxtapose blade stack 92 with graphite target 98.
• chamber 74 was evacuated; targets 96, 98 were cleaned by DC sputtering for five minutes; blades 92 were then RF cleaned in an argon environment at a pressure of ten millitorr at a power of 1.5 kilowatts and an argon flow of 200 seem for two minutes; the argon flow reduced to 150 sccm at a pressure of two millitorr in chamber 74; shutter 114 in front of molybdenum target 96 was then opened; and target 96 was sputtered to deposit a molybdenum layer 58 of about 200 angstroms thickness on the blade edges 94.
• Shutter 114 was closed and carousel 88 was rotated 90* to juxtapose blade stack 92 with graphite target 98.
• Pressure in chamber 74 was maintained at two millitorr with an argon flow of 150 sccm, shutter 116 was opened, and graphite target 98 was sputtered at 600 watts to deposit a DLC layer 60 of about 300 angstroms thickness on molybdenum layer 58.
• the DLC coatings 60 were firmly adherent on resulting blades, and the DLC tips 70 had a radius of about 500 angstroms.

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• Life Sciences & Earth Sciences (AREA)
• Forests & Forestry (AREA)
• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Dry Shavers And Clippers (AREA)
• Physical Vapour Deposition (AREA)
• Cutting Tools, Boring Holders, And Turrets (AREA)
• Polishing Bodies And Polishing Tools (AREA)
• Chemical Vapour Deposition (AREA)
• Mechanical Treatment Of Semiconductor (AREA)
• Perforating, Stamping-Out Or Severing By Means Other Than Cutting (AREA)
• Nonmetal Cutting Devices (AREA)

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• 1992
  • 1992-04-22 HU HU9303018A patent/HUT69255A/hu unknown
  • 1992-04-22 JP JP51189992A patent/JP3439761B2/ja not_active Expired - Lifetime
  • 1992-04-22 KR KR1019930703244A patent/KR100241239B1/ko not_active IP Right Cessation
  • 1992-04-22 AU AU21842/92A patent/AU666659B2/en not_active Expired
  • 1992-04-22 CZ CZ19932275A patent/CZ288085B6/cs not_active IP Right Cessation
  • 1992-04-22 CA CA002102222A patent/CA2102222C/en not_active Expired - Lifetime
  • 1992-04-22 WO PCT/US1992/003330 patent/WO1992019425A2/en active IP Right Grant
  • 1992-04-22 RU RU93057879A patent/RU2108234C1/ru not_active IP Right Cessation
  • 1992-04-22 DE DE69230822T patent/DE69230822T2/de not_active Expired - Lifetime
  • 1992-04-22 AT AT92913377T patent/ATE190892T1/de not_active IP Right Cessation
  • 1992-04-22 EP EP92913377A patent/EP0582676B1/de not_active Expired - Lifetime
  • 1992-04-22 ES ES92913377T patent/ES2143473T3/es not_active Expired - Lifetime
  • 1992-04-23 EG EG21792A patent/EG19582A/xx active
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  • 1992-04-25 CN CN92103958.1A patent/CN1039527C/zh not_active Expired - Lifetime
  • 1992-04-25 MY MYPI92000711A patent/MY107736A/en unknown
  • 1992-04-27 TR TR00370/92A patent/TR26981A/xx unknown
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