DE1553761A1 - Process for coating the cutting edges of sharpened devices - Google Patents

Description

DR.-ING. WALTER ABITZ DR. DIETER MORF

Patent attorneys

8 Munich 27, Pienzenauerstraße 28 Telephone 483225 and 4864 Y5 Telegrams: Chemindus Munich

April 21, 1966 £ 40 085

PHILIP MORRIS INCORPORATED

100 Park Avenue, New York 17, N.Y., V.St.A.

Method of coating the cutting edge of the sharpened

devices

üio invention bo relates to a method of coating dor cutting or cutting edges of sharpened or polished Devices. The invention relates in particular to a method for coating, the finely honed cutting edges

ORIGINAL

009845/1437

A kO 085 ^V

of sharpened devices with appropriate attention or Preferred substances by means of an electric plasma jet or a gas flow which by other means such as eloktrischo resistance heating or combustion more suitable Gases ι is brought to the required temperatures.

The cutting of sharpened devices such as knives, razor blades, scissors, scissors, scalpels, surgical mess :? » and the like, are affected by certain errors and limitations in their structure. On the one hand, the material from which the devices can be made is limited to those substances which can be conveniently shaped or rolled into initial shapes by known steel rolling processes, which are suitable for treatment in known grinding devices, since grinding is the most widely used means for Training and Schiirfon dor cutting represents. The grinding process, however, generates heat, which can predetermine the properties of the cutting edge material, and also leaves small unions in the cutting edge surfaces. Must be this is the · Y / O £ en undesirable woil thereby the cutting force is orhöht, wolche in use NIIF the device auagetibt. Veiter are the also substances which are shaped or rolled into shapes suitable for grinding by known steel whale processes, are limited in their strength and

- 2 - BATH ORIGlNAt

0098A5 / U37

085

therefore largely restrict the shape of the chordal edge and the cutting edge angle that can be formed on the same. In addition, since the physical and chemical properties of the Schncldenmatariala are the same as the strong eingesehränkton physical and chemical properties dee carrier _t severe restrictions join the resistance of the .Schneiden go against corrosion, deformation, dulling and derglelchon oin wo1ehe, the useful life of the cutter Bosch envy or the honing of which is necessary roofing, if that is possible or expedient.

The main object of the present invention is to provide a method sura coating the cutting edges of sharpened or ground Devices with suitable substances to create their visual cutting effect improve su while reducing the cutting force required. Another goal is to reduce the Corrosion on the cutting edges as well as a substantial extension the useful life of the cutting edges or cutting edges.

In particular, the invention is concerned with coating dar cutting razor blades with suitable substances. The substances can be organic or inorganic materials be familiar with the blade material by applying the very otarkcn heat of an electric piasea beam or one on Another way heated gas source can only be thermally fused to the area of the cutting edges. He-

00 981/61 H 37

> BATHROOM

A kO 085 k-

findungsgeraäß can gehonton cutting the Raaierkliiig ^'1;! "are first coated with a suitable material, for example polytetrafluoroethylene (Teflon). The Teflon coating and the blade cutting edges are then exposed to an electric plasma jet which heats the coating and the cutting edges to a sufficient temperature before the coating is bonded to the cutting material. Instead of coating the cutting edges beforehand, the coating or covering material can be applied to the cutting edges simultaneously with the application of the electric plasma jet. In the latter case, the coating material, which is preferably in fine powder form, although it can also be used in rod form, is introduced into the electric plasma jet gun in or near the plasma, which heats the material to or near the melting temperature during a period at the same time the material is conveyed to the cutting edges, where there is no problem with the cutting edges.

οι inventive method is equally suitable, Applying a bog seal material to any object, let the application of heat if desired to restrict to a limited area, in particular If no heating to a very high temperature is required is. The use of an electrical plasma

OO 98 AS ₁ JU 37. bad original

085

jet pistol a very important feature of the present Invention.

The invention is illustrated in greater detail, for example, with the aid of the figures explained. Ee shows

Figure 1 is an ochomatic oblique view in which there Coating a stack of razor blades with a jet Electric plasma gun is shown, the Blade cutting edges are prepared beforehand «in ·» suitable Material have been coated and this material thermally with the effect of the electric plasma jet the cutting edges are pre-melted,

FIG. 2 shows a section through a razor blade, in which, on an enlarged scale, the one on the cutting edge of the same attached coating is shown,

Figure 3 is a schematic representation of the device, which is used to coat the cutting edges of a continuous Stroifens of sharpened razor blade material is used, the coating material being the first

¹ ι ι ■ rf

applied to dlο cutting edges and then melted onto it is done by the coating and the JUingenachneid * edge of plasma flow of a jet gun for electric Plasma is exposed

- 5 - ■ BATHROOM

009 * ^{45/1437 ΒΛ}

A kO 085 /

Figure k is a side view showing an adjustment of electrical plaama jet guns with respect to the cutting edge of the blade strip which can be used in the apparatus shown in Figure 3;

FIG. 5 in a final view, in which other arrangements of electric plasma jet guns are shown, which in the implementation of the inventive method can be applied

FIG. 5a shows a section dureji dl · DUs * of a known one Electric plasma jet gun which can be used to direct a plasma flow against both sides to straighten a razor strip,

Figure 6 shows the same representation as in Figure 3 ωLt the Except that the coating material in a single Process step is attached to the cutting edges of the blade strip and fused with these.

FIG. 7 shows a vertical section through an embodiment form of an electric plasma jet gun, which is used in the The device shown in Figure 6 can be used, in particular the devices but supplying the sole in powder form directly into the plasma

009I46 / -1O7

A kO 085

Flow shown let,

FIG. 8 shows a vertical section through a known nozzle with maximum residence time, which is shown in FIG electric plasma jet gun can be used,

FIG. 9 shows the point in which the tip of the nozzle shown in FIG

FIG. 10 shows a schematic plan view in which it is shown is like a blade cutting edge coated according to the invention is subjected to a paper cutting act.

The same reference symbols are used for the same parts throughout the description.

In Figure 1, a stack of razor blades 10 is shown, the manner shown therein by some known establishment can be clamped together. The blades 11 are beinpj «laweiae unilateral injector or insertion blades, on which a single cutting edge 12 is ground and is withdrawn, although they could also be provided with two cutting edges. The blades can be made of different materials be made such as carbon steel, »stainless steel, or extremely strong plastic. Each © blade 11 has one

- 7 -

Q09845 / -U37 ^BAD

A kO 085

single cutting edge 12, which is formed by two intersecting or tapered sides. According to the method used in Figure 1 are the Blade cutting edges 12 with a suitable anti-friction Material 13 precoated in a known manner, for example by spraying on, where the material bit the blade material can be thermally fused. The coating material can be made of tungsten carbide, alloys, bimetallic metal oxides, polytetrafluoroethylene, polychlorotrifluoroethylene, fluorinated teloners, polyethylene, Stearic acid, benzic acid, types of wax, nylon, polyataiden, Polyacetals and polycarbonates are made, however not necessarily limited to it. It is noted that the method explained with reference to FIG is not limited to coating the cutting edges of razor blades, but equally to coating the cutting edges of any sharpened device. Further it is not necessary that the cutting devices are set up for coating in a group, since they can also be used individually or as a continuous Strips, as in production on a production line, can be coated.

As can be seen from Figure 1, the coating

material 13 is the cutting edge of the blades, however not fused with the same until it is very intense

8 ^BAD ORIGINAL

Q09845 / U37

A kO 085

Heat of an electric plasma jet gun 14 is known Type is suspended. In short, - is the spray- odor jet gun for electric plasma consisting of a pair of electrodes, between which an arc in the jtedium «in ·· strongly ionized inert gas such as argon, helium, nitrogen or hydrogen or mixtures of these gases, burns »The gun therefore generates a plasma jet or« in · Plasma flow 15 of highly heated ionized gas and maintains this, with the gas according to the invention against the coated cutting edges of the blades is straightened. The plasma jet 15 is used to concentrate Hitzo on both the coating materials and on

v. ■

to use the cutting edge of the blade in order to bring it at least to the temperature at which the coating mntarially fuses with the blade material. When fusing the coating with the blades in the darge a toll Lon Woise, the tip of the plasma jet gun (the nozzle that is not used) is preferably held at a distance of about 3.8-10.2 cm from the rear edges of the blade. In practice, of course, the plasma jet envelops the cutting edge 12. It is only not shown in FIG. 1 in such a way that it strikes the rear edges in order to show other details.

Vio can be seen from Figure 1, the electrical plasma

BATH

009846 / U37

A kO 085

jet gun 1U is preferably held so that the plasma jet strikes the cutting edge at an angle of 15 ° to the horizontal. Veiter, the gun is moved relative to the cutting edge with a longitudinal movement LL ¹ and a vertical movement VV ¹ , as shown. To effect these movements, the pistol can be moved by hand or it can be attached to a suitable, powered holding device. Ss is apparent that the mentioned movements of the gun can be \ exerted k Beeohiohtung vm on only one side of the Klingensehneidkante iu merge, and in that the gun must be placed on the opposite side of the Klingenetapele to the Beeohiohtung on the other side of the cutting edge su verecbjselsen. ^k% is arranged to line good equilateral fusion of Beeohichtungematerials on both sides of the cutting edge can be ersielt, indan the electrical Plassiastrahlpistole ^, that the plasma jet or plasma flow 15 * "us the same meets the Sohneidkante under a * angle of 90 ° as shown . With this special arrangement, the pistol Ik * is given a longitudinal movement 1 » _O - ^L _O 'and a lateral or transverse movement TT ^{1 at the} same time.

A major advantage when using electrical levers Plasma jet gun for heating the cutting edges of the

_{10 m} ORIGINAL BATHROOM

Q09845 / U37

A kO 085

Sounding consists in this; that the heating is localized only on the cutting edge, so that the heat is out this is quickly dissipated by the rest of the blade body, which acts as a heat sink and thereby prevents oxidation of the blade edge material.

FIG. 2 shows a section through a blade 20, whose Blade 21 covered with a fused coating 22 is shown, for example, as plastic, although it can also consist of any of the inorganic substances previously enumerated. The observation thickness has been exaggerated for clarity as it is actually only 0.025 mm (0.001 inch) or even less to ask nut.

FIG. 3 illustrates the process used to cross over a continuous strip 30 of razor clinic material with a single cutting edge. The continuous strip is sharpened with a known sharpener 35 to form a cutting edge 31 on each blade section 32. The term "sharpening" includes rough grinding, fine grinding, honing and honing. The strip is then sprayed with a suitable solvent 33 by means of a suitable spray head in order to remove abraded metal and abrasive particles from the sharpening device 35

BATH 0984 57 U 37

A ** 0 083

To remove cutting edges along with any remaining coolant used for honing. The blade strip is then drawn through under an air dryer 36, which dries and preheats the blades. The cutting edges of the strip are then coated with a coating substance 37, such as tetrafluoroethylene powder (thickness 0.25 camouflage or 10 microns), as a suspension by means of a suitable spray device 38. The advancing strip is then passed under a second dryer 39, which dries the coating material so that it forms a relatively thin, beveled layer over the cutting edges and their sides. The coating is then fused with the son by means of one or more solid electric plasma jet guns , the plasma jets of which are directed only against the cutting edge of the strip. The strip is then advanced through a conventional blade breaker 42 which breaks the strip into individual blades as shown.

Vm is the application of to facilitate Figure 3 illustrated coating Ever driving, one or more electrical plasma jet guns 451 46 may be disposed above the moving strip, as shown in FIG. 4 Ea a pistol can be attached to each side of the blade stripe and arranged in such a way that

" ¹² ~ BAD ORIGINAL

009845 / U37

A kO 085

that the plasma jets 47 »48 from them under one Angle of 30 to the horizontal and parallel to the The plane of the blade edge against the blade edge be judged. The gun settings are nioht limited to those shown in Figure 4, but can also be selected as shown in Figure 5, for example, a pair of guns 50, 51 on both sides of the blade strip 52 and their plasma jets 53, 54 at an angle of 0 ° are directed against the cutting edge. It is also possible that the pistols are at an angle of 15 ° below of the horizontal as shown in dashed lines.

Figure 5a shows yet another pistol assembly to directing a plasma from a nozzle against both sides of a blade at the same time. The plasma jet gun 5 & is arranged directly below a moving blade strip 57. The pistol has a nozzle 100 which has a recess 101 in which the blade λ trθifen moves. The DUse has symmetrical slots 102, 103, from which in each case the plasma jets 58 bsw. 59 occurred against the ground cutting edges of the Blade strelfen at an angle between 0 ° and 15 °

, ■. ; ■ fr-

be directed below the horizontal. -. '

- 13 - ORIGINAL BATHROOM

009845 / U37

A kO 085

In the following examples the coating is one continuous strip of razor blade material accordingly the method illustrated in FIG. 3.

Example I.

A continuous strip of steel razor blade material with a single edge was sharpened as shown in Figure 3 by cutting edges on each blade portion of the strip. The cutting edges were cleaned with a solvent and hot air was directed against the cutting edges in order to dry and preheat them. Sine air spray gun was then used to spray a coating of Polyt · trafluorä thy lon (Teflon) as a dispersion of 2-1 / 2 <f> Teflon powder in WaSuer to the cutting. The sprayed-on coating was then dried by passing the blade trowel under a flow of hot air. The coating was then welded to the cutting edges by passing the strip under one or more solid electric plasma jet pistols, the plasma jets emerging from them touching the coating and the cutting edges. AVCO plasma generators with an AVCO nozzle were modeled as pistols 9OI332-I was used as the anode and Model 901066-1 was used as the cathode. Dia Pistolon were made under a square of 15

0 0 9 8 A % i \% 5 7 bad original

A kO 085

disposed to the blade edges and the distance from dor Öüsonapitze to the blade edge was 8.89 cm (3 "5 inches The PlaaniagaestriJBiung in each gun was 0.873 1 minute at 15 Argon jo _f 6 ° C (60 ^° F) and atmospheric pressure (1.85 The plasma arc voltage was 28-30 V with a plasma arc current of 800 A. The speed of the stripes past the plasma beam was 25 feet per minute.

The coated blade was then broken from the strip. When examined, the Teflon coating showed good fusion and generally smooth appearance. The blade then became a paper cutter subject. In short, this consisted of the blade, as shown in FIG. 10, in a holding device was arranged at an angle of 20 to the horizontal. The paper sample 110 was then longitudinally the line of action 111 intersected. The coating on car blade was in the detached from the cutting edge 113 Area 112 partially wiped while a little or no destruction of the coating on the cutting edge occurred.

Ball game II

The procedure according to Example I was repeated with the following modifications: The grazing speed

-15- _B AD ORIGINAL

0098A5 / U37 "~

A kO 085 / L

was reduced to 3.81 m (12.5 * feet) J «minute, d» r Plasma arc current was reduced to 300 A, the DlUenspitso was at a distance of 3.81 ca (1.5 inches) Brought by the razor blade, the pistol was under an) angle of 0 ° to the horizontal · attached and dio PIq stnaga β flow was at 0.651 1 J · minute at 15.6 ° C and atmospheric pressure (1.38 SCFM) reduced.

Its coated blade, broken off from the strips, was then examined. The fusion was excellent and the Toflon coating was remarkably clear without any sign of cloudiness. The blade then became a » Subjected to shaving test, Bs- was a noticeable reduction in resistance and the required scraping force.

According to the invention, it is also possible to use the coating material to the edge of a continuous strip of razor blade material and simultaneously to merge with the same. As can be seen from FIG. 6, the blade strip 6 * 0 is cut with a cutter 67 by means of sharpened by a sharpener 61; with a solvent geeftubort. the solvent dried and the blade strip Preheated as described above. The blades are then placed under one or more electric blades

- 16 - ORIGINAL BATHROOM

0098A5 / U37

A kO 085

Plastrah-lpletolon 62, 63 carried in dao Pia oma 6 '», 65, supplied by v / olchotn dao Boachichtungamaterlal 66 in powder form, the coating material being fed into the plaamaetjet guns by means of a carrier gas. The bottom sealing material is supplied from a suitable storage container 68 which contains a device, such as a screw conveyor (not shown), in order to precisely meter the powder flow, and which is connected by lines 69 to the Piasroa spray guns. It is necessary that the powder flow rate into the plasma jet platolon is precisely controlled in order to achieve a uniform flow at a low feed rate, for example 10 g per minute, see below. A uniform powder distribution can be used to obtain a coating of the same "for" i (; or thickness on the blade strip. In practice, it has been found that a feed without a corner with a minimal web area gives excellent results. Penetration into the plasma beam is transformed from a powdery to a liquid state and the plasma beams are then directed onto the cutting edges.

Boi Teflon causes the heat dos Plaomaetrahle one teilto & J.se decomposition doe Teflons, making extraordinary ctarlc jfea /; Aers3jd9 i "roio radicals sabilden uerdon, those with

- 17 0098A5 / U37

dom material of the blade edge react to a chemical Binding · to form avischen dönaolbon. As a result, the Plasma jets have a double effect, the coating material and the blade edge on the one for the fusion between the Beschiohtungsmaterial and the Klingftnmatarial required temperature to heat. The KJ.ingensfcreifen is then broken into individual blades , as described above.

In the example below is the simultaneous application lind fusion of sizing substances onto a continuous strip of razor blade material described.

Example III

Blades were sharpened on a continuous strip of steel razor blade material. The cutting edges were then coated with Teflon powder with a particle size of 10 microns by controlling the "plesma jet or electrical plasma jet oil?" Speed were suspended. The Teflon powder was introduced directly into the plasma jet, in which at least the surface parts of the powder particles were melted into a liquid state before they were deposited on the Klingansch media. The Teflon

^ _J8 . BADORLGiNAL

009845 / U37

A 40 085

in its melted and softened state with
the cutting edge as soon as ea touched it. Ee were the
the following values are applied:

Used tea Gaa (plaema and carrier) Gas flow (plaema)

Gaest flow (

L Power consumption due to plasma clean- » piatole

Verwailisait dos Teflon powder in the

Plaematic map
Streiftingaeca windiness

argon

1,982 S ³ per hour at and Atajo ephärendruclc (70 SCFH)

» ³ each hour at 15, ß ° and Atiao ephttrendruok (7f2 SCFH)

20 kV

0.0002 - 0.0005 seconds 399 ⁰ ^ ST ⁰ C (750 ^O ~ 800 ° F) 6, to * (20 feet) j min.

A coated blade, broken off from the strip, became eodami tested on a normal Raoiertoetplatto. It left calibrated a smooth strange effect and considerably improved

determine ■

IV ■

A kcnttnuierl.i.chor strips aua atHhlerneia Hasierklingen-mateirial A cutter © was sharpened, as in Figure 6

-. 19 0098 AS / U37

085

shown, Schneidon do form the strip on each blade section. The cutting edges were then cleaned with a suitable solvent, after which the _{strips were dried and preheated in the same manner as described in Example I (the} strip was moved at a rate of 6.10 η (20 feet) per minute) A pair of electric plasma jet pietolons were passed through, one of which was placed on either side of the cutting edge of the strip.All guns were AVCO plan generators with AVCO nozzles, model IPS-IO6O as anodes and model 901066-1 as cathodes. Teflon powder was used d i. fed directly into the plasma, each Pistol® at a controlled rate. the Piasmagasstrtimung (argon) in the guns was 0.519 per 1 minute at 15.6 ° C and AtMoaphftrendruok (1.1 SCFM) · flow dom carrier gas was 0.151 1 j " Minute at 15.6 ° C and A tmoaphtir final pressure (0.32 SCFM). The arc voltage was 25 - 28 V with an arc current of 4 00 A. The cutting edges are positioned and the holes are fastened at a distance of 5 * 1 (2 inches) from the blades. The softened Teflon was caught in the plasma beam and the blade cutting edges passed through it, the Teflon melting instantly when it hit the cutting edge.

- 20 - ORIGINAL BATHROOM

0098A5 / U37

A 40 085 II

A © blade was then broken off from the strip and examined. The Toflon coating was clear, adhered good on and of uniform thickness. It remained intact when the blade was operated in the manner described in Example X. was subjected to a paper chopping dead.

Can be 7 shows a AuefUhrungeform an electrical Plaemaatrühlpistole, 'what' in the illustrated in Figure 6 apparatus. The gun can be placed in the positions shown in FIGS. 4 and 5 with respect to the blade strip. As can be seen from FIG. 7, the pistol has a rear housing part 70 and a front housing part 71, a cathode 72, which can be made of tungsten, and a nozzle 73, which serves as an anode. Pl & emagaa is introduced into the cathode caimaer 74 by means of a line 75 and the housing is provided with KUhlwa β «recognized 76 , which are goapoisted by means of an inlet line 77 and an outlet line 78. The Doschichtungematerial is in powder form by a suitable conduit 79 * · ^η a bushing fed to the anode 73 60, from where ·· · Platraa is eingoftLhrt 81 in there. . '

Figvir 8 bo ig ^ eire vorzvi ^ sv / oise execution shape of the nozzle

- 21 -

BAD ORlGtNAL

009845/14 37

A kO 035

or anode 90, velcha in the one shown in FIG Plasma jet piofcole can be used. The DUa let provided with an implementation 91, which the pulverigo sizing material a good bit before of the mouth: 92 dor introduces Dliso into the plasma. This Feature results in a maximum length of stay (0.0002 0.0005 Seconds) of the material in the plasma to ensure sufficient Ensure material is heated before exiting the gun. It also becomes a beeroxO control of the Plastnaetstrahl enables and the The power required for operation is reduced, for example in particular in the case of Teflon powder important as the Teflon heats to at least 399 ° C (750 ° F) must be made to ensure that it is geachaolsen to eu of a proper viscosity or fluidity

■ ■ ... r ·

so that it adheres well to the edge of the blade. On the other hand, substances like carbides require higher temperatures » melt by at least parts of the surface of the same eu and thereby ο a metallurgical bond between the respect «« atar.1al and the cutting edge of the device or. Tool »to effect safely. The plasma jet gun can of course be operated in such a way that they achieve these higher levels Tomr-instruments generated. .

Auo dom It can be seen from the above that the

- 22 -

0 0 9 8 A 5 / U 3 7 ^BAD

A kO 085

underlying invention has a number of advantages known method for coating the cutting edge of sharpened devices or tools achieved. she is conveniently applicable for production line processes, since only some simple device merlanals, such as the electric plaeaa jet pistol, spray cleaner and the like, must be used and proportionately cheap and easy to operate asu and have little space requirements. This is in contrast to the »heavyweight igon systems, such as heating stoves, as previously used which besides their high cost and bulkiness require a great deal of time, are difficult to control and undesirable additional handling of the Sharpened instruments require »These disadvantages also prevail in other known procedures» for example bei'rolchon, which are heated by electrical Resistances or induction or by ultraviolet radiation is applied,

Another important advantage of the present invention is that the use of coating tubes: en is made possible, which so far as felt "the use * thought to be too expensive in cutting implements, and it was because of the difficulty in finding these substances Carrier to attach., By the present invention

~ 23 00984S / U37 BATH ORIGINAL

A 40 085

it also possible to use a wide variety of carrier substances to use such as carbon steel, stainless steel and even plastics with high strength.

Brfindungsgemäß is also proposed DAT "In wide range of ethylene ·«, propylene and tetrafluoroethylene monomers can be polymerized to reibungsoinderaden polymers within the electrical plasma jet gun before, the same sprayed onto the cutting edges, as shown in FIG. 6

BATH ORIGINAL 00 9 84 5/1437

Claims (1)

^{A k0 08} S _ψ γ * April 21, 1966 Claims 1. Procedure * u »overdraw the. Cutting of hardened " Ridden a "relb-changing material" around the. To improve tendon properties of the same, thereby ϊ
characterized that the cutting edges are brought into contact with the friction · - · hindering material and at the same time the material is exposed to the heat effect of a high temperature gas flow. ^'R,' and erhitsen us both on Oine Teaparatur what · cum fusion de · Material · ince sufficient to cutting · 2. The method according to claim 1, daduroh ffekennxeiohnet, that a high temperature air flow, ait that there * r <9ibung «binding material and the cutting edges heated been the plasma jet of an electric plasma jet gun is used. ^ 3. Virfahron according Auapruch * 1, daduroh in DAB dna reibun ^ stiindcrnds Materi X & aiii by spraying 'is applied dia cutting, form below, inter alia, a thin, the Schneidon büdockende Materia Lech layer, . 25 00984S / U37 ' A kO 085 ftf whereby the high temperature gas flow is directed against the matorial layer and the cutting edges » to heat both su, put between them »Merger occurs. k . A method according to claim 1, characterized in that the friction-reducing material is applied to the cutting edges by being carried along in powder form in the high temperature gas flow, in which the same is melted in a liquid state, the high temperature gas flow counteracting the Schneidon is directed to the material on the - ■> To apply cutting « 5 * Method according to claim 1, daduroh gekennmeiehaet » that as a friction reducing material polytetrafluoroethylene is used. 6th Method according to Claim 5, characterized in that the polytetrafluoroethylene is applied to the cutting edges with a thickness of not more than 0.025 mm (0.001 inohm). · 7, ancestors according to claim 1, characterized in that - 26 - BATHROOM Q09845 / U37 A 40 085 Π that as a sharpened device to which the tendon edges should be coated ^ razor blades are used. 8. The method according to claim 7 »characterized in that the razor blades are used in the form of a continuous strip of razor blade material, are formed in which cutting, wherein the continuous running strip is passed through a station in which the blades are cleaned * by ski · If residues are removed from the same, and that the continuous strip is then passed through a station in which a liquid dispersion of the coating material is sprayed onto the cutting edges, after which the strip is guided in a controlled manner close to the connections of an electric plasma jet gun, whereby the überzugenaterlal and the cutting edges are brought into contact with the plasma jet of the electric plasma jet gun. 9. The method according to claim 1, characterized in that that the coating material as a powder in liquid Dispersion is applied to the cutting edges * 10. The method according to claim 2, characterized in that the Plaemaetstrahl only against the cutting parts of the . 27 - BATHROOM 009845 / U37 A kO 0S5 Cutters is directed. 11. Vg λ "driving on according to claim 2, characterized in that that the electric plane jet gun with a Nozzle is provided, which has a vertically recessed Has part through which the cutting devices held out be, and that plasma rays from svMsetrisoh opposite points in the recessed part are directed against the cutting edges. 12. The method according to claim 11, characterized in that that the plasma jets wipe at their "angle of" 0 ° and 15 ° below the horizontal against the cutting edges. 13. The method according to claim 2, characterized in that the tip of the electric plasma jet gun is arranged at a distance between approximately 3.8 ca (II / 2 inches) and 10.2 cm (k inches) from the cutting edges. Ik. Vci'fahrorr according to claim 7 »characterized in that <the razor ünß least near "an electric PlGsiaastx'ahlpietolQ be bypassed, said cutting dnran bofindlichon with the plasma jet d 'r - 28 - 0 0 9 0 U 5/1 h 3 7 BAD ORIGINAL A kO 085 electrical Plaemastraiilpistolo brought into contact were and that transfer material in the plasma jet is carried along by the same melted and through the beam is directed onto the cutting edges. 15. A method according to claim 8, characterized in that the continuous strip near the electrical P ^ asaaststrahlpiatole at a speed between about 3.80 m (12-1 / 2 feet) and 7 * 62 m (25 feet) per minute is passed by. BATH 009845 / U3