WO2004030875A1 - Lames et feuilles a base de zircone pour rasoirs et procede de fabrication associe - Google Patents

Lames et feuilles a base de zircone pour rasoirs et procede de fabrication associe Download PDF

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Publication number
WO2004030875A1
WO2004030875A1 PCT/US2003/030958 US0330958W WO2004030875A1 WO 2004030875 A1 WO2004030875 A1 WO 2004030875A1 US 0330958 W US0330958 W US 0330958W WO 2004030875 A1 WO2004030875 A1 WO 2004030875A1
Authority
WO
WIPO (PCT)
Prior art keywords
blade
zirconia
holes
foil
razor
Prior art date
Application number
PCT/US2003/030958
Other languages
English (en)
Inventor
William Anthony Denne
Original Assignee
Eveready Battery Company, Inc.
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from GB0222712A external-priority patent/GB0222712D0/en
Priority claimed from GB0223882A external-priority patent/GB0223882D0/en
Application filed by Eveready Battery Company, Inc. filed Critical Eveready Battery Company, Inc.
Priority to EP03759604A priority Critical patent/EP1545841B1/fr
Priority to JP2004541944A priority patent/JP4398864B2/ja
Priority to DE60335271T priority patent/DE60335271D1/de
Priority to US10/528,767 priority patent/US7357052B2/en
Priority to AU2003275328A priority patent/AU2003275328A1/en
Priority to AT03759604T priority patent/ATE490853T1/de
Publication of WO2004030875A1 publication Critical patent/WO2004030875A1/fr

Links

Classifications

    • BPERFORMING OPERATIONS; TRANSPORTING
    • B26HAND CUTTING TOOLS; CUTTING; SEVERING
    • B26BHAND-HELD CUTTING TOOLS NOT OTHERWISE PROVIDED FOR
    • B26B21/00Razors 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
    • B26B21/54Razor-blades
    • B26B21/58Razor-blades characterised by the material
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B26HAND CUTTING TOOLS; CUTTING; SEVERING
    • B26BHAND-HELD CUTTING TOOLS NOT OTHERWISE PROVIDED FOR
    • B26B19/00Clippers or shavers operating with a plurality of cutting edges, e.g. hair clippers, dry shavers
    • B26B19/38Details of, or accessories for, hair clippers, or dry shavers, e.g. housings, casings, grips, guards
    • B26B19/384Dry-shaver foils; Manufacture thereof
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B26HAND CUTTING TOOLS; CUTTING; SEVERING
    • B26BHAND-HELD CUTTING TOOLS NOT OTHERWISE PROVIDED FOR
    • B26B21/00Razors 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
    • B26B21/54Razor-blades
    • B26B21/56Razor-blades characterised by the shape

Definitions

  • This invention relates generally to blades and foils for razors, and more particularly relates to zirconia based blades and foils for razors, as well as methods for producing same.
  • Electric razors with cutting foils and wet shave razors with cutting blades have been in use for many decades. With respect to electric razors, they comprise a pierced foil and cutter.
  • the foil is generally electroformed from nickel, which provides a very sharp edge but of limited hardness.
  • Electric razor foils are generally made by electroforming nickel. This is a relatively expensive process and the hardness of the resulting nickel cutting edges is not that high.
  • the razor blades traditionally have a straight cutting edge that extends the length of the razor head.
  • Safety razors have guards to control the position of the skin with respect to the cutting edge, so that the cutting edge rides over the skin but cuts protruding hair.
  • Such razor blades have traditionally been made from high quality carbon steel.
  • the innovation of using stainless steel has been fraught with the difficulty of forming and holding an ultra sharp edge.
  • Ground ceramic razor blades tend to have a ragged microstructure rather than rounded, and consequently dig into skin rather than sliding over it. Accordingly, it is a general object of the present invention to provide zirconia based blades and foils, and methods of fabrication thereof, that overcome the above-identified drawbacks of prior razors.
  • the present invention resides in a method of fabricating a foil for an electric razor.
  • a substrate is provided including a combustible surface.
  • a foil plan form is generated on the combustible surface with a zirconia based ink such that flow of the ink under surface tension forces generates sharp edges to the foil.
  • the foil plan form is fired to burn away the combustible surface such that zirconia forms a durable foil that maintains sharpness over repeated use.
  • the zirconia based ink can include partially stabilized or fully stabilized zirconia.
  • the printing of the foil plan form can be accomplished by either screen printing or vacuum forming.
  • the combustible surface can include, for example, a plastic film of high surface finish, and is preferably hydrophilic.
  • the present invention also resides in a method of fabricating a blade for a wet shave razor.
  • a substrate is provided including a combustible surface.
  • a zirconia based ink is generated on the combustible surface such that the ink wets the substrate and edges of the ink slightly to form a plurality of sharply pointed meniscus to serve as cutting surfaces.
  • the ink is fired to burn away the combustible surface and to harden a rounded, sharp edge on the plurality of meniscus.
  • the sharp edges of the meniscus have an edge radius of about 50 nanometers or less.
  • the present invention further resides in a blade for a wet shave razor that is bidirectional and comprises a substrate curved along a direction of blade movement to conform to a contour of the skin of a user.
  • the blade substrate defines a plurality of holes each having a periphery. A leading portion of the holes in the direction of blade movement serves as a guard, and a trailing portion of the holes serves as a cutting edge.
  • the substrate includes partially stabilized or fully stabilized zirconia.
  • the holes are arranged in an array that can be either even or staggered.
  • the shape of the holes can be, for example, rectangular or diamond-shaped.
  • FIG. 1A is a top plan view of a razor blade substrate defining an array of rectangular slots serving as cutting edges in accordance with the present invention.
  • FIG. IB is a top plan view of a razor blade substrate defining an array of staggered rectangular slots serving as cutting edges in accordance with another embodiment of the present invention.
  • FIG. 1C is a top plan view of a razor blade substrate defining an array of diamond-shaped slots serving as cutting edges in accordance with a further embodiment of the present invention.
  • FIG. 2 is an elevational, cross-sectional view of the razor blade of FIG. 1 showing a curved contour of the blade in contact with the skin of a user.
  • an electric razor foil can be made from zirconia ceramic.
  • the zirconia may be partially or fully stabilized.
  • the foil may be fabricated by screen printing the foil plan form onto a hydrophilic surface with a zirconia based ink, such that flow of the ink under surface tension forces generates very sharp edges to the ceramic foil.
  • the planar hydrophilic surface may be combustible so that it vanishes during firing.
  • the surface is preferably a plastic film of good surface finish.
  • the foil network may be biaxially extensible to conform to the skin.
  • the cutter may also be in the form of a zirconia foil.
  • the zirconia print and plastic film may be formed prior to firing. Vacuum forming may be appropriate.
  • Appropriate binders and plasticisers in the zirconia ink may stop cracking of the ceramic print during the forming process.
  • Partially stabilized zirconia has the hardness and toughness of tool steel. It has excellent wear characteristics and takes a very keen edge. While it is much more expensive, the quantity in a razor foil is minimal and it may be fabricated more cheaply than electroforming.
  • a razor foil pattern may be precisely screen printed onto a plastic film with a zirconia ink. If the film is slightly hydrophilic it may be arranged, by controlling the ink properties, such that the edges of the print may run slightly under the influence of surface tension forces to provide an extremely sharp edge. Even a low cost plastic film may have a surface finish approaching optical quality and the zirconia print will accurately reproduce this.
  • the printed plastic film may be fired in the conventional manner. The plastic will burn away at a low temperature and the zirconia will form a very thin foil of extreme toughness. It will maintain its sharpness for a long time.
  • the foil pattern can be printed in a manner that permits biaxial extension to follow the contours of the skin.
  • a cutter in foil form can also be fabricated which will follow the outer foil and provide a flexible cutting surface.
  • the printed plastic may be vacuum formed if desired. This permits the forming of the profiled cutters used in current multi head shavers. The form may also be exploited to assist with maintaining dimensional stability during the firing process.
  • razor blades can be fabricated from a ceramic ink that is screen printed on a combustible surface and then fired.
  • the ceramic is preferably stabilized or partially stabilized zirconia.
  • the combustible surface is preferably a plastic film of high surface finish.
  • the ink vehicle and combustible surface may be so chosen that the ink wets the combustible surface.
  • Stabilized zirconia forms exceptional cutting blades. It is extremely strong, tough and hard. In thin sheets it may be very pliable. It has been discovered to be an excellent medium for razor blade fabrication. The raw material is very expensive compared with steel and is expensive to diamond machine. Cutting edges in zirconia are conventionally created by diamond machining, but this process produces ragged edges on a micro-scale which tend to dig into skin rather than slide over it. This, of course, is disastrous in a razor blade.
  • the ink comprises very finely powdered ceramic in a binder and solvent. It is possible to choose the composition of ink such that it wets the substrate and the edges of the print flow slightly to form a sharply pointed meniscus. On firing, the substrate may burn away and the meniscus will form a very sharp edge. The firing process causes the finely powdered grains to sinter into a solid mass. This process may be exploited to form an edge to the blade which is rounded on a microscale. With modern milling techniques, the powder particle size may be some tens of nanometers.
  • This fabrication technique offers the advantages of large scale mass coupled with low materials cost and no finishing processes.
  • a metallic or ceramic razor blade can be curved and define a plurality of holes or slots, some or all of which incorporate a cutting edge as part or all of their periphery.
  • a razor blade is indicated generally by the reference number 10.
  • the blade 10 defines a plurality of holes or rectangular slots 12 that preferably form an array.
  • the array of slots 12 includes five columns 14, 16, 18, 20 and 22.
  • the array can include a fewer or greater number of columns than that illustrated without departing from the scope of the present invention.
  • a portion of the periphery of the slots 12 serve as cutting edges that are well protected within the slots. As a result, the edge of the blade is no longer in need of careful protection.
  • the longer edges of the rectangular slots 12 are trailing edges 24 and leading edges 26.
  • the blade 10 further defines interconnecting spokes 28 between shorter edges 30 of the rectangular slots 12 for enhancing the rigidity of the blade.
  • a periphery 32 of the blade 10 may be used to retain the blade in a razor.
  • the leading edges 26 serve as a guard, and the trailing edges 24 serve as the cutting edge.
  • the blade 10 can be used in a direction opposite to that indicated by the arrow A. When used in such opposite direction, the edges 24 are the leading edges serving as the guard, and the edges 26 are the trailing edges serving as the cutting edges.
  • FIG. IB a blade in accordance with another embodiment of the present invention is indicated generally by the reference number 110.
  • the blade 110 defines a plurality of holes or staggered rectangular slots 112 that form an array.
  • the array of slots 112 includes five columns 114, 116, 118, 120 and 122.
  • the slots in adjacent columns are positioned in staggered relationship to one another to provide a consistent cutting surface along a direction of the blade transverse to that of the direction of movement.
  • a portion of the periphery of the slots 112 serve as cutting edges.
  • the longer edges of the rectangular slots 112 are trailing edges 124 and leading edges 126.
  • the blade 110 further defines interconnecting spokes 128 between shorter edges 130 of the rectangular slots 112 for enhancing the rigidity of the blade.
  • a periphery 132 of the blade 110 may be used to retain the blade in a razor.
  • the leading edges 126 serve as a guard, and the trailing edges 124 serve as the cutting edge.
  • the blade 110 can be used in a direction opposite to that indicated by the arrow A. When used in such opposite direction, the edges 124 are the leading edges serving as the guard, and the edges 126 are the trailing edges serving as the cutting edges.
  • a blade in accordance with a further embodiment of the present invention is indicated generally by the reference number 210.
  • the blade 210 defines a plurality of holes or staggered diamond-shaped slots 212 that form an array.
  • the blade 210 also preferably defines partial or half -diamond-shaped slots 213 at ends of the array for even distribution of cutting surfaces between sides of the blade.
  • the array of slots 212 includes five columns 214, 216, 218, 220 and 222. The slots in adjacent columns are positioned in staggered relationship to one another to provide a consistent cutting surface along a direction of the blade transverse to that of the direction of movement.
  • portions of the periphery of the slots 212 serve as cutting edges.
  • the diamond-shaped slots 212 each include trailing edges 224, 225 and leading edges 226, 227.
  • a periphery 232 of the blade 210 may be used to retain the blade in a razor.
  • the leading edges 226, 227 serve as a guard, and the trailing edges 224, 225 serve as the cutting edge.
  • the blade 210 can be used in a direction opposite to that indicated by the arrow A. When used in such opposite direction, the edges 224, 225 are the leading edges serving as the guard, and the edges 226, 227 are the trailing edges serving as the cutting edges.
  • a blade in accordance with the present invention may have an overall curvature to expose different angles of blade to the skin.
  • a curved blade 310 defines an array of holes or slots 312 in contact with skin 313 of a user during a shaving operation.
  • the array of slots 312 includes five columns 314, 316, 318, 320 and 322.
  • a hair 323 is shown being cut by a trailing or cutting edge 324 of one of the holes 312.
  • the curvature and flexibility of the blade 310 may be predetermined to offer the maximum ability to follow skin contours. Several cutting edges 324 may be in contact with the skin simultaneously.
  • the leading edges 326 of the holes or slots 312 control the access of the skin 313 to the cutting edges 324 of the hole 312.
  • the blade may be formed from metal by electroforming or by grinding away dimples in a planar shim.
  • the blade may also be formed by screen printing ceramic ink as an array of holes, and then firing the print.
  • the rheology of the ink may be arranged so that the flow of the periphery of the wet print may form a meniscus which becomes a polished razor edge on firing.
  • the ceramic is preferably partially stabilized or fully stabilized zirconia ceramic.
  • the ceramic may also be ground and polished after firing if desired.
  • Razor blades traditionally have a straight cutting edge.
  • An array of holes with cutting edges around their periphery in accordance with the present invention provides a longer cutting edge per square millimeter of blade and a tighter control of the angle at which the skin meets the blade. This results in a more rapid and closer shave with less chance of nicking the skin.
  • such an array may be made by electroforming. Electroforming is relatively expensive for disposable blades, however, and nickel, which is the only practical metal for this technique, is not exceptionally hard.
  • An alternative is to form an array of indentations in a planar metal shim, and then to grind away the raised bumps to create holes surrounded by a cutting edge.
  • a better process is to screen print the blade pattern with partially stabilized zirconia ink. If the rheology of the ink and the nature of the substrate are carefully chosen, the edges of the print flow to create a wetting meniscus. On firing, this meniscus naturally creates a polished razor edge.

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  • Engineering & Computer Science (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Forests & Forestry (AREA)
  • Mechanical Engineering (AREA)
  • Manufacturing & Machinery (AREA)
  • Dry Shavers And Clippers (AREA)
  • Producing Shaped Articles From Materials (AREA)

Abstract

Selon l'invention, de la pâte de zirconium stabilisée ou partiellement stabilisée peut être imprimée par sérigraphie sur un film hydrophile se présentant sous la forme d'une maille. Lors de la cuisson, ledit film se transforme en une feuille très coupante (10, 110, 210, 310) pour rasoirs électriques présentant des caractéristiques d'usure excellentes. Du zircone stabilisé ou partiellement stabilisé peut également être imprimé par sérigraphie sur un film plastique mouillable puis cuit afin de produire des lames de rasoir de faible coût présentant un tranchant excellent. Une lame de rasoir incurvée (310) comprenant un ensemble de trous (312), qui présentent chacun une périphérie à tranchant de couteau (324), offre un contrôle et un pouvoir de coupe de la surface de la peau supérieurs à une lame à simple ou double tranchant.
PCT/US2003/030958 2002-10-01 2003-10-01 Lames et feuilles a base de zircone pour rasoirs et procede de fabrication associe WO2004030875A1 (fr)

Priority Applications (6)

Application Number Priority Date Filing Date Title
EP03759604A EP1545841B1 (fr) 2002-10-01 2003-10-01 Lames et feuilles a base de zircone pour rasoirs et procede de fabrication associe
JP2004541944A JP4398864B2 (ja) 2002-10-01 2003-10-01 レザー用ジルコニアベースブレード及びフォイルの製造方法
DE60335271T DE60335271D1 (de) 2002-10-01 2003-10-01 Klingen und scherfolien auf zirkoniumdioxidbasis für rasierer und verfahren zur herstellung derselben
US10/528,767 US7357052B2 (en) 2002-10-01 2003-10-01 Zirconia based blades and foils for razors and a method for producing same
AU2003275328A AU2003275328A1 (en) 2002-10-01 2003-10-01 Zirconia based blades and foils for razors and a method for producing same
AT03759604T ATE490853T1 (de) 2002-10-01 2003-10-01 Klingen und scherfolien auf zirkoniumdioxidbasis für rasierer und verfahren zur herstellung derselben

Applications Claiming Priority (6)

Application Number Priority Date Filing Date Title
GB0222712A GB0222712D0 (en) 2002-10-01 2002-10-01 Zirconia razor foil
GB0222712.2 2002-10-01
GB0223567A GB0223567D0 (en) 2002-10-01 2002-10-10 Ceramic razor blade
GB0223567.9 2002-10-10
GB0223882A GB0223882D0 (en) 2002-10-01 2002-10-15 Perforated razor blade
GB0223882.2 2002-10-15

Publications (1)

Publication Number Publication Date
WO2004030875A1 true WO2004030875A1 (fr) 2004-04-15

Family

ID=32073908

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/US2003/030958 WO2004030875A1 (fr) 2002-10-01 2003-10-01 Lames et feuilles a base de zircone pour rasoirs et procede de fabrication associe

Country Status (4)

Country Link
EP (1) EP1545841B1 (fr)
JP (1) JP4398864B2 (fr)
AU (1) AU2003275328A1 (fr)
WO (1) WO2004030875A1 (fr)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US8104181B2 (en) 2006-10-13 2012-01-31 Panasonic Electric Works Co., Ltd. Outer blade for reciprocation-type electric shaver and method of producing the same

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2580088C (en) 2018-12-21 2021-05-26 Brengor Innovation Ltd Razor

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5018274A (en) * 1990-04-05 1991-05-28 The Gillette Company Safety razor blade
US20030063155A1 (en) * 1998-01-22 2003-04-03 Keiichi Nakao Method of forming an electronic component using ink

Family Cites Families (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE641901C (de) * 1937-02-17 Paul Geier Rasiergeraet
US2989804A (en) * 1959-06-30 1961-06-27 Edgar Bernhard Self protected shaving device having multiple cutting edges
US3870776A (en) * 1973-01-02 1975-03-11 Metalized Ceramics Corp Method for making ceramic-metal structures
US4105493A (en) * 1975-07-05 1978-08-08 The Gillette Company Production of shaving foil
GB2075404B (en) * 1980-04-30 1983-10-12 Wilkinson Sword Ltd Razors
DE3208081A1 (de) * 1982-03-06 1983-09-08 Braun Ag, 6000 Frankfurt Verfahren zur herstellung einer siebartigen scherfolie fuer einen elektrisch betriebenen trockenrasierapparat mit erhebungen auf ihrer der haut zugewandten flaeche
FR2584333B1 (fr) * 1985-07-02 1987-10-16 Desmarquest Ceramiques Tech Rasoir a tete monobloc, a lame en oxyde de zirconium a longue duree de vie
GB9207054D0 (en) * 1992-03-31 1992-05-13 Gillette Co Methods of manufacturing perforated foils
US5604983A (en) * 1994-04-14 1997-02-25 The Gillette Company Razor system

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5018274A (en) * 1990-04-05 1991-05-28 The Gillette Company Safety razor blade
US20030063155A1 (en) * 1998-01-22 2003-04-03 Keiichi Nakao Method of forming an electronic component using ink

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See also references of EP1545841A4 *

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US8104181B2 (en) 2006-10-13 2012-01-31 Panasonic Electric Works Co., Ltd. Outer blade for reciprocation-type electric shaver and method of producing the same

Also Published As

Publication number Publication date
EP1545841B1 (fr) 2010-12-08
AU2003275328A1 (en) 2004-04-23
JP2006501034A (ja) 2006-01-12
JP4398864B2 (ja) 2010-01-13
EP1545841A4 (fr) 2006-09-13
EP1545841A1 (fr) 2005-06-29

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