USH640H - Inductive sintering of polymers to blades - Google Patents

Inductive sintering of polymers to blades Download PDF

Info

Publication number
USH640H
USH640H US07/188,423 US18842388A USH640H US H640 H USH640 H US H640H US 18842388 A US18842388 A US 18842388A US H640 H USH640 H US H640H
Authority
US
United States
Prior art keywords
blade
magnetic field
manufacturing
polymeric material
blades
Prior art date
Legal status (The legal status 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 status listed.)
Abandoned
Application number
US07/188,423
Inventor
Jonathan Nizel
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Gillette Co LLC
Original Assignee
Gillette Co LLC
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
Application filed by Gillette Co LLC filed Critical Gillette Co LLC
Priority to US07/188,423 priority Critical patent/USH640H/en
Assigned to GILLETTE COMPANY, THE, A CORP. OF DE reassignment GILLETTE COMPANY, THE, A CORP. OF DE ASSIGNMENT OF ASSIGNORS INTEREST. Assignors: NIZEL, JONATHAN
Application granted granted Critical
Publication of USH640H publication Critical patent/USH640H/en
Abandoned legal-status Critical Current

Links

Images

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
    • B05D3/00—Pretreatment of surfaces to which liquids or other fluent materials are to be applied; After-treatment of applied coatings, e.g. intermediate treating of an applied coating preparatory to subsequent applications of liquids or other fluent materials
    • B05D3/02—Pretreatment of surfaces to which liquids or other fluent materials are to be applied; After-treatment of applied coatings, e.g. intermediate treating of an applied coating preparatory to subsequent applications of liquids or other fluent materials by baking
    • B05D3/0254—After-treatment
    • B05D3/0281—After-treatment with induction heating
    • 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
    • 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
    • B05D2258/00—Small objects (e.g. screws)

Definitions

  • the present invention relates to the manufacture of razor blades and more particularly to the manufacture of a razor blade having a coating of polymeric material disposed on the edge surfaces thereof.
  • the various coating supplied to the blade edges have been formulated with an attempt to eliminate the undesirable effects which occur in the shaving process that may cause irritation to the skin of the blade user.
  • blades have been treated by the coating of a polymeric material to the surface of the blade cutting edge by means of a sintering process.
  • the process of applying the polymer material to the razor blade is accomplished by application of the polymeric material, in solution, to the blade and heating the blade in an oxygen-free environment causing the polymeric material to become sintered to the blade edge surface.
  • Heating of the blade to produce the sintering has, in general, been accomplished by infra-red or resistance heating of the blade to a temperature in a range of between 200° C. to 400° C.
  • Various examples of such a process are disclosed in U.S. Pat. No. 3,224,900 issued to Creamer et al.
  • Another object of the invention is to improve polymer to blade bonding by reducing the potential for gross cross-linking of excess polymer material.
  • Still a further object of the invention is to reduce the energy requirements for sintering of the polymeric material to the blade edge surface by the use of inductive sintering.
  • a method of manufacturing a razor blade having a coating of polymeric material disposed on the edge surfaces of the blade which includes the steps of providing a chamber having an oxygen-free atmosphere therein and a means with the chamber for creating a rapidly changing magnetic field.
  • Polymeric material is applied to the edge surfaces of the blade and the blade is retained in the changing magnetic field whereby the current induced by the alternating magnetic field is effective to raise the temperature of the blade and cause sintering of the polymeric material to the blade edge surfaces.
  • a method of manufacturing a razor blade having a coating of polymeric material disposed on the edge surfaces thereof includes the steps of providing a chamber having an oxygen-free atmosphere therein and an induction coil having an alternating current applied thereto to create a rapidly changing magnetic field of between 1 megahertz and 100 megahertz within the chamber.
  • a polyethylene resin material is applied to the edge surfaces of the blade and the blade is retained in the changing magnetic field at a rate whereby the current induced by the magnetic field raises the temperature of the blade to between 200° C. to 400° C. to cause sintering of the material to the blade edge surfaces.
  • FIG. 1 is a schematic elevational view depicting a step in a prior art process for the manufacture of razor blades having a polymer coating applied to the edge thereof;
  • FIG. 2 is a fragmentary elevational view taken in the area II--II showing a portion of the prior art blade of FIG. 1, taken on an enlarged scale for clarity;
  • FIG. 3 is a schematic elevational view depicting one step in the process of the manufacture of a razor blade having a polymer coated edge, carried out in accordance with the teaching of the present invention.
  • FIG. 4 is a fragmentary elevational view taken in the area IV--IV showing a portion of the blade of FIG. 4 taken on an enlarged scale for clarity.
  • the preparation of the razor blades for coating in the present invention is similar to that employed in the prior art, in that the blades are first cleaned with a solvent or detergent to dissolve grease and dirt which may have accumulated on the blades, and to prepare a surface which is receptive to the coating to be affixed to the blade surface.
  • a carrier-type device which may be of any type well known in the art, and are coated with the polymeric material such as a polyethylene resin.
  • the resin may be applied in solution by spraying or brushing the material onto the blade surface in a manner to provide a substantially uniform coating on the blade surface.
  • a blade stack 10 comprising a plurality of blades 12 are mounted on a retainer 14 and a coating of polymeric material is applied as described above.
  • the blade stack 10 is then subjected to radiant heating from an infra-red heating source 16 for a length of time and at a heating intensity which is effective to raise the temperature to between 200° C. to 400° C. to cause sintering of the material to the blade surface.
  • FIG. 2 there is schematically shown the effect of external heating on the blade surface wherein the heat must pass through the polymeric material to heat blade surface. This results in blade edge 18 having little of the polymer material deposited on the surface due to its not retaining the heat from the heating source 16 in light of its relatively small cross-section and large surface area.
  • FIGS. 3 and 4 there is schematically shown a device for carrying out the method of the present invention.
  • the blade stack 10 having a plurality of blades 12 is supported by a retainer 14 for treatment in the present process.
  • the blades 12 are cleaned and a polymeric material in the form of a polyethylene resin is applied to the blades 12 which are supported by the retainer 14 for treatment.
  • An induction coil 20 is provided in a container from which the oxygen is removed by the introduction of a non oxygen containing gas and an alternating current is applied to the coil 20 to produce a frequency in the range of 1 megahertz to 100 megahertz at the blade stack 10.
  • the high frequency causes sintering of the polymeric material to the blade surfaces including the blade edge as is shown in FIG. 4.
  • the inducing of an alternating current along the body of the blade 12 at frequencies high enough, are considered to result in a skin effect on the surface of the blade 12 as depicted by the dot-dash lines of FIG. 4.
  • This skin effect produces the highest current densities, and therefore the highest heating, at the blade edge 18.
  • the rapidly changing magnetic field in close proximity to the blades 12 will induce a current which will generate heat for sintering the blade edge 18, which being relatively small in cross-sectional area, will heat preferentially.
  • the polymer material 19 is therefore more evenly bonded to the blade 12 and the potential for gross cross-linking of excess polymer is reduced.
  • the amount of energy required for sintering for the polymer material to the blade 12 is reduced over that required by the use of infra-red heating.

Landscapes

  • Life Sciences & Earth Sciences (AREA)
  • Forests & Forestry (AREA)
  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Application Of Or Painting With Fluid Materials (AREA)
  • Details Of Cutting Devices (AREA)
  • Moulding By Coating Moulds (AREA)

Abstract

A method of manufacturing a razor blade is disclosed wherein a polymer material is coated onto the blade edge. The polymer material is applied to the blade edge in a coating solution after which the blade is passed through a rapidly changing magnetic field in close proximity to the blade, which induces a current to generate heat for sintering the material to the blade edge.

Description

BACKGROUND OF THE INVENTION
The present invention relates to the manufacture of razor blades and more particularly to the manufacture of a razor blade having a coating of polymeric material disposed on the edge surfaces thereof.
In the prior art, it is known to manufacture razor blades having various coatings which have been developed to provide the blades with a protection against atmospheric conditions as well as contact with various materials during storage or the shaving process which materials would tend to degrade the basic material of the blade.
In addition to the protection of the stainless steel, or other material, from which the blade is manufactured, the various coating supplied to the blade edges have been formulated with an attempt to eliminate the undesirable effects which occur in the shaving process that may cause irritation to the skin of the blade user.
In order to accomplish the above, blades have been treated by the coating of a polymeric material to the surface of the blade cutting edge by means of a sintering process. Generally, the process of applying the polymer material to the razor blade is accomplished by application of the polymeric material, in solution, to the blade and heating the blade in an oxygen-free environment causing the polymeric material to become sintered to the blade edge surface. Heating of the blade to produce the sintering has, in general, been accomplished by infra-red or resistance heating of the blade to a temperature in a range of between 200° C. to 400° C. Various examples of such a process are disclosed in U.S. Pat. No. 3,224,900 issued to Creamer et al.
It is an object of the present invention to provide an improvement to the prior art process of applying a coating of polymeric material to the edge surfaces of a razor blade through the introduction of induction heating in the manufacturing process.
Another object of the invention is to improve polymer to blade bonding by reducing the potential for gross cross-linking of excess polymer material.
Still a further object of the invention is to reduce the energy requirements for sintering of the polymeric material to the blade edge surface by the use of inductive sintering.
SUMMARY OF THE INVENTION
The aforementioned objects and other objects which will become apparent as the description proceeds are accomplished by providing a method of manufacturing a razor blade having a coating of polymeric material disposed on the edge surfaces of the blade which includes the steps of providing a chamber having an oxygen-free atmosphere therein and a means with the chamber for creating a rapidly changing magnetic field. Polymeric material is applied to the edge surfaces of the blade and the blade is retained in the changing magnetic field whereby the current induced by the alternating magnetic field is effective to raise the temperature of the blade and cause sintering of the polymeric material to the blade edge surfaces. In a more detailed aspect of the invention, a method of manufacturing a razor blade having a coating of polymeric material disposed on the edge surfaces thereof includes the steps of providing a chamber having an oxygen-free atmosphere therein and an induction coil having an alternating current applied thereto to create a rapidly changing magnetic field of between 1 megahertz and 100 megahertz within the chamber. A polyethylene resin material is applied to the edge surfaces of the blade and the blade is retained in the changing magnetic field at a rate whereby the current induced by the magnetic field raises the temperature of the blade to between 200° C. to 400° C. to cause sintering of the material to the blade edge surfaces.
BRIEF DESCRIPTION OF THE DRAWING
The foregoing and other features of the invention will be more particularly described in connection with the preferred embodiment, and with reference to the accompanying drawing wherein:
FIG. 1 is a schematic elevational view depicting a step in a prior art process for the manufacture of razor blades having a polymer coating applied to the edge thereof;
FIG. 2 is a fragmentary elevational view taken in the area II--II showing a portion of the prior art blade of FIG. 1, taken on an enlarged scale for clarity;
FIG. 3 is a schematic elevational view depicting one step in the process of the manufacture of a razor blade having a polymer coated edge, carried out in accordance with the teaching of the present invention; and
FIG. 4 is a fragmentary elevational view taken in the area IV--IV showing a portion of the blade of FIG. 4 taken on an enlarged scale for clarity.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The preparation of the razor blades for coating in the present invention is similar to that employed in the prior art, in that the blades are first cleaned with a solvent or detergent to dissolve grease and dirt which may have accumulated on the blades, and to prepare a surface which is receptive to the coating to be affixed to the blade surface.
After washing the blades, they are dried and placed on a carrier-type device which may be of any type well known in the art, and are coated with the polymeric material such as a polyethylene resin. The resin may be applied in solution by spraying or brushing the material onto the blade surface in a manner to provide a substantially uniform coating on the blade surface.
Referring now to the drawings and in particular to FIGS. 1 and 2, the prior art method is shown wherein a blade stack 10 comprising a plurality of blades 12 are mounted on a retainer 14 and a coating of polymeric material is applied as described above. The blade stack 10 is then subjected to radiant heating from an infra-red heating source 16 for a length of time and at a heating intensity which is effective to raise the temperature to between 200° C. to 400° C. to cause sintering of the material to the blade surface.
Referring to FIG. 2, there is schematically shown the effect of external heating on the blade surface wherein the heat must pass through the polymeric material to heat blade surface. This results in blade edge 18 having little of the polymer material deposited on the surface due to its not retaining the heat from the heating source 16 in light of its relatively small cross-section and large surface area.
Referring now to FIGS. 3 and 4, there is schematically shown a device for carrying out the method of the present invention. As in the prior art method depicted in FIGS. 1 and 2, the blade stack 10 having a plurality of blades 12 is supported by a retainer 14 for treatment in the present process. As with the prior art blades, the blades 12 are cleaned and a polymeric material in the form of a polyethylene resin is applied to the blades 12 which are supported by the retainer 14 for treatment.
An induction coil 20 is provided in a container from which the oxygen is removed by the introduction of a non oxygen containing gas and an alternating current is applied to the coil 20 to produce a frequency in the range of 1 megahertz to 100 megahertz at the blade stack 10. The high frequency causes sintering of the polymeric material to the blade surfaces including the blade edge as is shown in FIG. 4.
Referring now to FIG. 4, the inducing of an alternating current along the body of the blade 12 at frequencies high enough, are considered to result in a skin effect on the surface of the blade 12 as depicted by the dot-dash lines of FIG. 4. This skin effect produces the highest current densities, and therefore the highest heating, at the blade edge 18. Thus, the rapidly changing magnetic field in close proximity to the blades 12 will induce a current which will generate heat for sintering the blade edge 18, which being relatively small in cross-sectional area, will heat preferentially. The polymer material 19 is therefore more evenly bonded to the blade 12 and the potential for gross cross-linking of excess polymer is reduced. In addition, the amount of energy required for sintering for the polymer material to the blade 12 is reduced over that required by the use of infra-red heating.

Claims (6)

I claim:
1. A method of manufacturing a razor blade having a coating of polymeric material disposed on the edge surface thereof which includes the steps of providing a chamber having an oxygen-free atmosphere therein and a means for creating a rapidly changing magnetic field within said chamber, applying a polymeric material to the edge surface of the blade, and retaining said blade in said magnetic field whereby the current induced by said magnetic field is effective to raise the temperature of said blade and to cause sintering of said polymeric material to said blade edge surfaces.
2. A method of manufacturing a razor blade as set forth in claim 1 wherein said means for creating a magnetic field comprises an induction coil having an alternating current applied thereto.
3. A method of manufacturing a razor blade as set forth in claim 1 wherein material is a polyethylene resin.
4. A method of manufacturing a razor blade as set forth in claim 1 wherein said material is raised to a temperature of 200° C. to 400° C.
5. A method of manufacturing a razor blade as set forth in claim 1 wherein the frequency of the magnetically induced current is between 1 megahertz and 100 megahertz.
6. A method of manufacturing a razor blade having a coating of polymeric material disposed on the edge surfaces thereof which includes the steps of providing a chamber having an oxygen-free atmosphere therein and an inductive coil having an alternating current applied thereto to create a rapidly changing magnetic field within said chamber, applying a polyethylene resin material to the edge surfaces of the blade and passing said blade through said magnetic field at a rate whereby the current induced by said magnetic field raises the temperature of said blade to between 200° C. to 400° C. to cause sintering of said material to said blade surfaces.
US07/188,423 1988-04-29 1988-04-29 Inductive sintering of polymers to blades Abandoned USH640H (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
US07/188,423 USH640H (en) 1988-04-29 1988-04-29 Inductive sintering of polymers to blades

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US07/188,423 USH640H (en) 1988-04-29 1988-04-29 Inductive sintering of polymers to blades

Publications (1)

Publication Number Publication Date
USH640H true USH640H (en) 1989-06-06

Family

ID=22693080

Family Applications (1)

Application Number Title Priority Date Filing Date
US07/188,423 Abandoned USH640H (en) 1988-04-29 1988-04-29 Inductive sintering of polymers to blades

Country Status (1)

Country Link
US (1) USH640H (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1995008421A1 (en) * 1993-09-22 1995-03-30 The Gillette Company Method of applying polymers to razor blade cutting edges

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3224900A (en) 1962-10-04 1965-12-21 Philip Morris Inc Method of making polyethylene coated razor blades

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3224900A (en) 1962-10-04 1965-12-21 Philip Morris Inc Method of making polyethylene coated razor blades

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1995008421A1 (en) * 1993-09-22 1995-03-30 The Gillette Company Method of applying polymers to razor blade cutting edges
US5477756A (en) * 1993-09-22 1995-12-26 The Gillette Company Method of applying polymers to razor blade cutting edges
CN1045560C (en) * 1993-09-22 1999-10-13 吉莱特公司 Method of Coating Polymer on the Edge of a Shaving Blade

Similar Documents

Publication Publication Date Title
AU627647B2 (en) Plastic powder coated strip
ATE188145T1 (en) METHOD FOR TREATING THE CUTTING EDGES OF RAZOR BLADES
ATE93900T1 (en) ENGRAVED MICRO-CERAMIC COATED CYLINDER AND COATING METHOD THEREOF.
DE59607561D1 (en) Method and device for continuous processing of essentially flat or strip-shaped workpieces made of open-pore wood materials and the like in the edge area
US7090897B2 (en) Electrically conductive MDF surface
DE69506476D1 (en) Process for the surface treatment and coating of plastic molded articles and an article coated with this process
JP2003515460A (en) A method for modifying wood surfaces by electrical discharge at atmospheric pressure
USH640H (en) Inductive sintering of polymers to blades
DE69028088D1 (en) Method and device for producing microwave-sensitive sheet material
GB1029363A (en) Treatment of chromium surfaces
ATE116163T1 (en) METHOD FOR COATING HOUSEHOLD ITEMS AND HOUSEHOLD ITEMS.
RU2146565C1 (en) Process of deposition of coat on cutting edges
PT1339502E (en) PROCESS FOR THE PRODUCTION OF A PARTIAL OR COMPLETE COAT OF ACTIVE SUBSTANCES ABOVE AND WITHIN IMPLANTS AND ONPLANTS
ATE109040T1 (en) METHOD AND APPARATUS FOR MANUFACTURING METAL CAN BODY WITH INSIDE LAYER.
JPS63108930A (en) Manufacture of metallic die
RU95119043A (en) METHOD FOR PRODUCING COATED ULTRA-DISPERSED POWDER OF ZIRCONIUM DIOXIDE
EP0566958A1 (en) Method for repairing a defective coating on a coated metal substrate
DE3170597D1 (en) Silicone polymer compositions for treating textile materials, processes for preparing the same, a process for treating textile materials and the coated textile material thus treated
JPS57169078A (en) Modifying method for material surface
FR2245423A1 (en) Paint hardening method for metal cup - inductive heating applied to rotating cup
Steine et al. Alloy Coating Post-Treatment
Kim et al. Development of functionally gradient W/Mo material by laser beam
JPS62149379A (en) Method for uniformly curing coated film on painted steel sheet of cut sheet by induction heating
RU92004453A (en) METHOD FOR TREATING THE SURFACE OF METALS INTENDED FOR APPLICATION ON THEIR COATINGS
Chabrol et al. Determination of Internal Stresses in Laser Treated Surfaces and Cladding

Legal Events

Date Code Title Description
AS Assignment

Owner name: GILLETTE COMPANY, THE, A CORP. OF DE,MASSACHUSETTS

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:NIZEL, JONATHAN;REEL/FRAME:004899/0274

Effective date: 19880420

STCF Information on status: patent grant

Free format text: PATENTED CASE