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
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
  • B05D—PROCESSES FOR APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
  • B05D1/00—Processes for applying liquids or other fluent materials
  • B05D1/60—Deposition of organic layers from vapour phase
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
  • B05D—PROCESSES FOR APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
  • B05D5/00—Processes for applying liquids or other fluent materials to surfaces to obtain special surface effects, finishes or structures
  • B05D5/08—Processes for applying liquids or other fluent materials to surfaces to obtain special surface effects, finishes or structures to obtain an anti-friction or anti-adhesive surface
  • B05D5/083—Processes for applying liquids or other fluent materials to surfaces to obtain special surface effects, finishes or structures to obtain an anti-friction or anti-adhesive surface involving the use of fluoropolymers
• • 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
• • C—CHEMISTRY; METALLURGY
  • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
  • C09D—COATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR
  • C09D127/00—Coating compositions based on homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by a halogen; Coating compositions based on derivatives of such polymers
  • C09D127/02—Coating compositions based on homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by a halogen; Coating compositions based on derivatives of such polymers not modified by chemical after-treatment
  • C09D127/12—Coating compositions based on homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by a halogen; Coating compositions based on derivatives of such polymers not modified by chemical after-treatment containing fluorine atoms
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
  • B05D—PROCESSES FOR APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
  • B05D2202/00—Metallic substrate
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10S128/00—Surgery
  • Y10S128/14—Polytetrafluoroethylene, i.e. PTFE

Definitions

• Conventional steel safety razor blades to which the. present invention may be appliedto produce improved blades are from 0.003 to 0.015 inch-thick and havewedgeshaped cutting edges, the included-solid angle of which is greater than 14 and less than 35;
• the faces or sides of some such cutting edges extend back from the edge for a distance upto as muchv astOJl inch or even more.
• Each face need notlbe .asingle planaruninterrupted continuous blade edgeuis composed may be either carbon steel or hardenable stainless steel. In either case it is hardened by asuitable'heat treatingprocess.
• the fluorocarbon integument or coating may extend over the entire wedge faces back from the ultimate edge or even farther, or it. may cover only the portion of the final facet immediately adjacent to the ultimate edge.
• the precise thickness of the integument does not appear to be critical, athin continuous adherent coating having a thickness of the order of an oriented monolayer of molecules having been found effective for the purpose of the present invention.
• the thickness of the integument need not be uniform throughout its extent.
• the fluorocarbon materials which may be used in practicing the present invention are solid materials and include a variety ofysolidv polymers of tetraliuoroethylene containing a chain at carbon atoms including. a. plurality of (-C'F -CF groups. These polymers may vary widely in molecularweight in the form in which they are used for applying to the cutting. edge, ranging from a. molecular weight of the order of 2000 or even lower to a molecular weight above 2,000,000.
• the terminal groups at the ends'of the carbon chains may also vary, depending, as is well known, upon the method of making the polymer. Polymers made in aqueous media are reported to have terminal carboxyl groups, while others may have hydrogen and/or chlorine atoms attached to the terminal carbon atoms .of the chain.
• the material may be applied to the blade cutting edge by placing the edgev in close proximity toa supply of the fluorocarbon while the latter is heated, to deposit a fluorocarbon coating on the cutting edge.
• Electrophoresis may also be employed to deposit the material from charged liquid dispersions thereof, or the cutting edge may be sprayed with or simply dipped in the dispersion and allowed to dry.
• Solid fluorocarbons having a molecular weight in the lower part of the above range may also be applied to the cutting edge by dipping the edge in a dispersion of the important as in thecaseof. conventional blades.
• particulate fluorocarbon in a volatile liquid medium or by spraying or brushing such a dispersion onto the edge, then evaporating the liquid medium.
• volatile liquid media which may be used are water, and such .Freons as dichlorodifiuoromethane, dichlorotetrafluoroethane, .trichlorotrifluoroethane, and mixtures thereof.
• the blade carrying the deposited solid fluorocarbon be baked at an elevated temperature of the orderiiof 200: to 750 F. for a period of time suflicient .for the fluorocarbon to become firmly adhered to the substrate.
• the time may vary'from lessthan two minutes up to 48 hours or more depending on the particular fluorocarbon employed, the nature of the substrate, the rapidity with which the coated blade is brought up to temperature, and the temperature achieved.
• the blade cannot be heated to temperatures higher than about 400 F. for more than five minutes without some tempering or softening of the blade.
• some softening or tempering of the blades can be tolerated since its disadvantages are more than offset by the improvement'in shavingeifectiveness brought about by the present invention.
• steel blades when heated to 300 to 320 F. must be baked for at least thirty minutes toachieve optimum results, although longer heating does noharm -to the coating.
• the integument on the cutting edge of the blade when the blade is ready for use may be extremely thin, as pointed out above, it is desirable, in order to produce such an integument, that the coating be substantially thicker at the time the baking step begins. Any excess material remaining on the cutting edge which does not bond to the substrate during the baking step is in the form of a loose film which can be readily removed by brushing or rubbing. It is not essential that this excess material be removed before the blade is used.
• the mag sten coil was heated electrically until the crucible temperature reached 700-750 F.
• the current was then controlled so that a pressure of 3 10 mm. of mercury was maintained during the heating which was continued for four hours.
• the blade was removed and showed a deposited layer on its cutting edge which exhibited interference colors in the light microscope.
• the blade was then placed in an air oven at 320 F. for 40 minutes.
• Example 2 A hardened stainless steel razor blade purchased on the open market was thoroughly cleaned by washing with trichloroethylene and dried; then its cutting edge was dipped into an aqueous colloidal dispersion containing 25% by weight of finely divided solid tetrafluoroethylene polymer (Du Ponts Teflon Clear Finish). Upon removal from the dispersion, the cutting edge of the blade carried with it a coating of the aqueous dispersion which was then dried for one hour at 120 F. in the atmosphere, after which the deposited coating was baked at 750 F. for 7 minutes.
• aqueous colloidal dispersion containing 25% by weight of finely divided solid tetrafluoroethylene polymer (Du Ponts Teflon Clear Finish).
• Example 3 A finely divided solid fluorocarbon polymer containing a chain of carbon atoms including a plurality of (-CF --CF groups and also containing a minor proportion (about 1% by weight) of chlorine atoms and a similar proportion of hydrogen atoms with a melting range of 265293 C. (Du Ponts Fluorowax TLT-17 Lot No. 2) was dispersed in a 40:60 mixture by weight of Freon l2 (dichlorodifluoromethane) and Freon ll4 (dichlorotetrafluoroethane) to from a dispersion containing 1% by weight of solids. This dispersion was sprayed from a pressure container onto the cutting edge of a Gillette razor blade, cleaned as described in the preceding examples; and the blade was baked at 330 F. in an air oven for 7 hours.
• Freon l2 diichlorodifluoromethane
• Freon ll4 diichlorotetrafluoroethane
• Example 4 The fluorocarbon solid described in Example 3 was dispersed in Freon 113 (trichlorotrifluoroethane) to form a dispersion containing 1% by weight of solids. The cutting edge of a Gillette razor blade, cleaned as described above, was dipped into this dispersion and allowed to dry in the atmosphere. The blade was then baked at 320 F. for 16 hours. Similar results were also obtained using similar dispersions containing up to 11% by weight of fluorocarbon polymer.
• Freon 113 trichlorotrifluoroethane
• Example 5 The fluorocarbon solid described in Example 3 was deposited onto a Gillette razor blade edge as described in Example 1 except that the temperature of the crucible was maintained at 335 F. and the heating continued for 10 minutes. The blades were removed from the vacuum chamber and showed interference colors on the cutting edge. Similar results can be obtained by heating at a temperature as low as 250 F. for a longer time. The blades were placed in an air oven at 320 F. for 15 minutes. Similar results were also obtained using times up to 16 hours at the same temperature.
• Example 6 The fluorocarbon solid described in Example 1 was heated in air at atmospheric pressure in a silica crucible to a temperature of 450 C. until a thick white smoke continuously emanated from the crucible.
• a Gillette razor blade cleaned as described above was held with its edge in the white smoke at a distance of three inches from the crucible for 10 minutes. By reason of its proximity to the crucible, the blade attained a temperature of the order of 300 F. during the deposition of the fluorocarbon on its cutting edge and required no further baking.
• a safety razor blade having on its cutting edge an adherent coating comprising a solid fluorocarbon polymer.
• a safety razor blade having on its cutting edge an adherent coating comprising a solid polymer of tetrafluoroethylene.
• a steel safety razor blade having on its cutting edge an adherent coating comprising a solid polymer of tetrafluoroethylene.
• a safety razor blade having on its cutting edge an adherent coating compirsing a solid polymer containing a chain of carbon atoms including a plurality of (--CF CF groups.
• a safety razor blade as claimed in claim 5 in which heating said deposited polymer to form a coating adherent to said edge.
• the method of treating a steel safety razor blade which comprises depositing on its cutting edge a composition comprising a solid polymer containing a chain of carbon atoms including a plurality of (CF -CF groups and also including terminal groups selected from the class consisting of carboxyl groups, hydrogen atoms and chlorine atoms, and heating said deposited polymer to form a coating adherent to said edge.
• the method of treating a steel safety razor blade which comprises depositing on its cutting edge a dispersion in a volatile liquid containing discrete particles of solid polymer containing a chain of carbon atoms including a plurality of (CF CF groups, evaporating said volatile liquid, and heating the resulting deposit at an elevated temperature to form a coating adherent to said edge.
• the method of treating a steel safety razor blade which comprises heating a solid polymer containing a chain of carbon atoms including a plurality of groups to a temperature sufiicient to vaporize a portion thereof, maintaining a cutting edge of said blade in said vapors to deposit a coating thereon, and heating the resulting deposit to form a coating adherent to said edge.

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• Life Sciences & Earth Sciences (AREA)
• Engineering & Computer Science (AREA)
• Forests & Forestry (AREA)
• Mechanical Engineering (AREA)
• Chemical & Material Sciences (AREA)
• Wood Science & Technology (AREA)
• Materials Engineering (AREA)
• Organic Chemistry (AREA)
• Application Of Or Painting With Fluid Materials (AREA)
• Knives (AREA)
• Dry Shavers And Clippers (AREA)
• Mechanical Treatment Of Semiconductor (AREA)
• Cleaning Implements For Floors, Carpets, Furniture, Walls, And The Like (AREA)
• Non-Silver Salt Photosensitive Materials And Non-Silver Salt Photography (AREA)
• Paints Or Removers (AREA)

Priority Applications (15)

Applications Claiming Priority (1)

Publications (1)

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ID=25340276

Family Applications (1)

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Cited By (40)

Families Citing this family (4)

Citations (7)

Family Cites Families (9)

• 0
  • NL NL123398D patent/NL123398C/xx active
  • LU LU39590D patent/LU39590A1/xx unknown
  • NL NL259570D patent/NL259570A/xx unknown
  • BE BE598698D patent/BE598698A/xx unknown
• 1959
  • 1959-12-31 US US863109A patent/US3071856A/en not_active Expired - Lifetime
• 1960
  • 1960-12-22 GB GB44051/60A patent/GB906005A/en not_active Expired
  • 1960-12-27 FR FR848021A patent/FR1299519A/fr not_active Expired
  • 1960-12-28 DE DEG31256A patent/DE1147141B/de active Pending
  • 1960-12-29 DO DO1960000898A patent/DOP1960000898A/es unknown
  • 1960-12-30 CH CH1458860A patent/CH402655A/de unknown
  • 1960-12-30 DK DK518260AA patent/DK110230C/da active
  • 1960-12-30 SE SE1267860A patent/SE191482C1/sv unknown
• 1964
  • 1964-07-29 OA OA50220A patent/OA00177A/xx unknown
  • 1964-11-07 CY CY20064A patent/CY300A/xx unknown
• 1965
  • 1965-12-30 MY MY29/65A patent/MY6500029A/xx unknown

Patent Citations (7)

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