DK167483B1

DK167483B1 - PROCEDURE FOR THE MANUFACTURING OF Wear-Resistant Coatings, Especially on Color Transfer Rollers

Info

Publication number: DK167483B1
Application number: DK078289A
Authority: DK
Inventors: Kurt Zecher; Wolfgang Schauer; Guenter Eisner
Original assignee: Zecher Gmbh Kurt
Priority date: 1987-07-14
Filing date: 1989-02-21
Publication date: 1993-11-08
Also published as: EP0322423B1; DE8709645U1; DK78289D0; DE8717972U1; WO1989000507A1; DK78289A; DE3773941D1; EP0322423A1

Description

DK 167483 B1DK 167483 B1

Opfindelsen angår en farveoverførselsvalse med en slidstærk belægning og en fremgangsmåde til fremstilling af belægningen som angivet i krav 1's og krav 7's indledninger.This invention relates to a color transfer roller having a durable coating and a method of preparing the coating as set forth in the preamble of claims 1 and claim 7.

Fra DE-A1-33 36 374 kendes en farveoverførselsvalse, hvis 5 kappelag fortrinsvis består af kobber, og i hvis kappeoverflade der er udformet fordybninger, hvorefter der eventuelt er udført en anodisk polering, og der galvanisk er påført et hårdkromlag på overfladen. Farveoverførselsvalser af denne art er under anvendelsen underkastet et stærkt slid, idet farvepartiklerne 10 og overfladen af papiret, på hvilket der skal trykkes, virker abrasivt.DE-A1-33-36374 discloses a color transfer roller, the five coat layers of which preferably consist of copper, and in whose casing surface there are recesses, after which an anodic polishing is possible and a hard chromium coating is applied to the surface. Color transfer rollers of this kind are subjected to a strong wear during use, the color particles 10 and the surface of the paper on which to print appear abrasive.

Fra UA-PS-4 301 730 kendes endvidere en farveoverførselsvalse af aluminium, der ved en flammesprøjternetode er forsynet med et hårdt oxidlag, som kun slides i ringe grad. Imidlertid 15 er aluminiumgrundlegemet meget ømfindtligt overfor slagpåvirkninger, således at der ofte optræder beskadigelser og afskalning af oxidlaget. Endvidere er flammesprøjtemetoden meget dyr og kan kun anvendes ved valser med groft rastermønster og medfører et ufordelagtigt tab på ca. 50% af farveoptagelseskapaciteten.Furthermore, from UA-PS-4 301 730 a color transfer roller of aluminum is known which, by a flame-spraying method, is provided with a hard oxide layer which wears only slightly. However, the aluminum base body is very sensitive to impact, so that damage and peeling of the oxide layer often occur. Furthermore, the flame spraying method is very expensive and can only be used with coarse raster pattern rollers and causes a disadvantageous loss of approx. 50% of the color absorption capacity.

20 Formålet med opfindelsen er at angive en farveoverførsels- valse, der kan fremstilles på forholdsvis enkel måde, har en forholdsvis stor farveoverførselskapacitet, som svarer tilnærmelsesvis til den graverede valse uden belægning, og som er væsentligt mere slidstærk og samtidig mere slagfast end de kend-25 te farveoverførselsvalser.The object of the invention is to provide a color transfer roller which can be manufactured in a relatively simple manner, has a relatively large color transfer capacity, which corresponds approximately to the engraved roller without coating, and which is substantially more durable and at the same time more impact-resistant than those known in the art. 25 tea color transfer rollers.

Denne opgave løses ifølge opfindelsen ved de i krav 11 s og krav 7's kendetegnende del angivne foranstaltninger.This task is solved according to the invention by the measures specified in claim 11 s and claim 7.

Denne opgave løses ifølge opfindelsen ved, at det påførte beskyttelseslag består af et sejt metal, i hvilket der 30 er indlejret hårdmaterialekorn med en kornstørrelse på 1-3 m, og at beskyttelseslaget har en lagtykkelse, der svarer til ca.This task is solved according to the invention in that the applied protective layer consists of a tough metal in which 30 hard material grains having a grain size of 1-3 m are embedded and the protective layer has a layer thickness corresponding to approx.

1.-3 gange kornstørrelsen.1-3 times the grain size.

Fordelagtige videre udformninger er angivet i underkravene.Advantageous further designs are indicated in the subclaims.

35 Fremgangsmåden og den ved denne fremstillede belægning kan i en videre udviklet form med fordel anvendes også i andre tilfælde, hvor der foruden en høj slidstyrke også kræves en i DK 167483 81 2 forhold til hårdmaterialekornenes kornstørrelse lille overflade-ruhed, eller hvor der optræder et af meget fint kornede materialer fortrinsvis i pastaform forårsaget abrasivt slid, eller hvor der forekommer kemisk aggressive slidstoffer.The process and the coating produced by this coating can advantageously be used also in other cases where, in addition to a high abrasion resistance, a small surface roughness in relation to the grain size of the hard material grains is also required or where a surface roughness occurs. of very fine grained materials preferably in paste form caused by abrasive wear or where chemically aggressive abrasives occur.

5 Et med hårdmaterialepartikler forsynet nikkellag er meget sejt og slagfast og er ved anvendelse på farvevalser væsentligt mere slidstærkt end den kendte hårdkrombelægning.A nickel-layered hard material particle is very tough and impact-resistant and, when applied to color rollers, is significantly more durable than the known hard chromium coating.

Det nikkel, der 'omgiver hårdmaterialepartiklerne, nedbrydes imidlertid langsomt som følge af abrasivt slid og en af 10 farvepartiklerne forårsaget kemisk påvirkning, således at hårdmaterialepartiklerne efter at have løsnet sig helt efterhånden går tabt. Dette abrasive og kemiske slid på nikkellaget elimineres i udstrakt grad ved en fordelagtig videre udformning .af belægningen, nemlig ved hjælp af en derpå anbragt tynd hårdfor-15 kromning, hvis lagtykkelse tilnærmelsesvist svarer til hårdma-terialepartiklernes kornstørrelse, hvorved der kan opnås en flere gange højere slidstyrke.However, the nickel surrounding the hard material particles is slowly decomposed as a result of abrasive wear and one of the 10 color particles caused chemical effect, so that the hard material particles, after being released, are completely lost. This abrasive and chemical wear on the nickel layer is extensively eliminated by an advantageous further shaping of the coating, namely by a thin hard chromium applied thereto, the layer thickness of which corresponds approximately to the grain size of the hard material particles, thereby obtaining several times higher wear resistance.

Belægningsmetoden med en hårdkromforsegling på det seje lag, der bærer hårdmaterialepartiklerne, kan med fordel også 20 anvendes til andre formål, idet hårdforkromningen medfører en meget glat overflade. Denne glathed af overfladen er overra-skande, idet det er almindelig kendt, at der ved pågalvanisering af et kromlag på steder, hvor fremmede partikler i underbunden danner forhøjninger, opstår huller eller spidser i kromlaget, 25 hvilket imidlertid, hvad omfattende praktiske forsøg har vist, ikke er tilfældet ved de hårdmaterialepartikler, der sammen med nikkellaget er påført ved galvaniseringen.Advantageously, the coating method with a hard chrome seal on the tough layer supporting the hard material particles can be used for other purposes as the hard chromium results in a very smooth surface. This smoothness of the surface is surprising, as it is well known that when co-plating a chromium layer in places where foreign particles in the bottom form elevations, holes or tips in the chromium layer occur, which, however, has shown extensive practical experiments. , is not the case for the hard material particles applied together with the nickel layer during galvanizing.

Indlejringen af hårdmaterialepartikler foretages hensigtsmæssigt i et basisk nikkelgalvaniseringsbad, hvor hårdmateriale-30 partiklerne, der holdes svævende, holdes i en konstant koncentration. På grund af hårdmaterialepartiklernes lille størrelse kan dette opnås ved en konstant cirkulation i galvaniseringsbadet med de deri svævende partikler. Derved opnås en tilsvarende ensartet fordelt indlejring af partiklerne i det gal-35 vaniserede lag, især ved en farveoverførselsvalse, således at farveafgiveisen bliver fuldstændig ensartet.Conveniently, the deposition of hard material particles is carried out in a basic nickel galvanizing bath, where the hard material particles kept suspended are kept at a constant concentration. Due to the small size of the hard material particles, this can be achieved by a constant circulation in the galvanizing bath with the particles floating therein. Thereby, a corresponding uniformly distributed embedding of the particles in the galvanized layer is achieved, especially by a color transfer roller, so that the color delivery becomes completely uniform.

Det har ved forsøg til påførsel af beskyttelseslag på den prægede overflade af farveoverførselsvalser overraskende 3 DK 167483 B1 vist sig, at det med en bestemt tangential hastighed af elektro-lyten med de deri svævende stoffer i forhold til den graverede overflade, der skal galvaniseres, kan opnås, at hårdmateriale— partiklerne hovedsageligt udfældes på stegene mellem fordybning-5 erne og ikke på stegenes sider eller på bunden af de kegle-stubformede fordybninger, således at der ved belægningen ikke fås en sådan forringelse af farveoptagelseskapaciteten, som ellers skulle forventes, men derimod endog en forøgelse af farveoptagelseskapaciteten, idet lagtykkelsen oven på stegene der-10 ved bliver større.Surprisingly, upon application of protective layers to the embossed surface of color transfer rollers, it has been found that with a certain tangential velocity of the electrolyte with the substances floating therein relative to the engraved surface to be galvanized, it is obtained that the hard material particles are precipitated mainly on the steps between the recesses and not on the sides of the ladders or on the bottom of the cone-stub-shaped recesses, so that the coating does not obtain such a deterioration in the color-picking capacity as would otherwise be expected, however. even increasing the color uptake capacity as the layer thickness on top of the steps thereby becomes greater.

Ved de kendte farveoverførselsvalser har man hidtil for at opnå en lang levetid af disse tilstræbt den højest mulige farvekapacitet ved hjælp af en dyb gravering og forholdsvis smalle stege, således af en i praksis ved farvetryk nødvendig 15 mindste farvekapacitet stadig er bevaret selv ved en delvis slidt valse. Da overfladebehandlingen ifølge opfindelsen af valsen ved indlejring af hårdmateriale i valsens yderste tynde lag, der kommer til berøring med papiret og raklerne, giver flere gange længere slidtider, og da det derunder beliggende 20 lag, i hvilket prægningen er udført, slides hurtigere, er det på fordelagtig måde muligt, kun at bearbejde farvevalserne til en sådan prægedybde, at deres farvekapacitet kun ligger lidt over mindstemålet. Endvidere kan der i de tilfælde, hvor man kan nøjes med et groft raster, anvendes en billigere rifling 25 i stedet for en prægning.The known color transfer rollers have so far sought to achieve the highest possible color capacity by means of a deep engraving and relatively narrow roasting so that a minimum color capacity necessary in practice for color printing is still maintained even at a partially worn one. roller. Since the coating according to the invention of the roller by embedding hard material into the outer thin layers of the roller which comes into contact with the paper and the racks gives several times longer wear times, and since the 20 layers in which the embossing is carried out wear faster, it is advantageously, only to process the color rollers to such a depth of color that their color capacity is only slightly above the minimum. Furthermore, in cases where a coarse grid can be satisfied, a cheaper rifle 25 can be used instead of an embossing.

Som hårdmetal kan der anvendes silicium, men også bl.a. siliciumkarbid, siliciumoxid, kornud, woiframkarbid* diamantstøv etc. kan anvendes.As carbide, silicon can be used, but also among other things. silicon carbide, silicon oxide, granular, tungsten carbide * diamond dust etc. can be used.

I fig. 1-5 er enkelthederne ved farvevalsen og de galva-30 niserede belægninger anskueliggjort. På tegningen viser: fig. 1 en farveoverførselsvalse stærkt formindsket, fig. 2 et delbillede af en plantegning af en farvevalses over-35 flade stærkt forstørret, fig. 3 et afsnit af et tværsnit gennem fig. 2, 4 DK 167483 Bl fig. 4 et tværsnit svarende til fig. 3 gennem yderligere en udførelse stærkt forstørret og fig. 5 et stærkt forstørret tværsnit gennem en belægning.In FIG. 1-5, the details of the color roller and the galvanized coatings are illustrated. In the drawing: FIG. 1 is a greatly reduced color transfer roller; FIG. Figure 2 is a partial view of a floor drawing of the surface of a color roller greatly enlarged; 3 shows a section of a cross section through FIG. 2, 4 DK 167483 B1 fig. 4 is a cross-sectional view similar to FIG. 3 through another embodiment greatly enlarged; and FIG. 5 shows a greatly enlarged cross-section through a coating.

55

Fig. 1 viser en farveoverførselsvalse i formindsket målestok. Denne består af et stållegeme 2 med en aksel 3, på hvilken en kobberkappe 1 er påkrympet eller pågalvaniseret. Overfladen 4 af kappen 1 er vist stærkt forstørret i fig. 2. Den 10 er ved roulettering eller fortrinsvis ved - prægning forsynet med fordybninger V, der fortrinsvis har et trapezformet tværsnit med flad bund B og med mellem fordybninger beliggende i forhold til bredden W af fordybningerne smalle stege S. Afstanden fra fordybning til fordybning er den såkaldte rasterafstand 15 R, der ved valser af høj kvalitet er f.eks. 70 mm. Efter den mekaniske fremstilling af fordybningerne V fjernes eventuelle grater hensigtsmæssigt ved galvanisk polering.FIG. 1 shows a reduced color transfer roller. This consists of a steel body 2 with a shaft 3 on which a copper sheath 1 is crimped or galvanized. The surface 4 of the casing 1 is shown greatly enlarged in FIG. 2. The 10 is by roulette or preferably by - embossing with recesses V, preferably having a trapezoidal cross-section with flat bottom B and having intermediate recesses relative to the width W of the recesses. The distance from recess to recess is the so-called raster spacing 15 R, which for high quality rollers is e.g. 70 mm. After the mechanical preparation of the recesses V, any burrs are conveniently removed by galvanic polishing.

Fig. 3 viser et tværsnit gennem det i fig. 2 viste efter, at laget 10 med indlejrede hårdmaterialekorn er påført på kobber-20 underbunden 1 med fordybningerne V.FIG. 3 shows a cross-section through the embodiment of FIG. 2, after the layer 10 with embedded hard material grains is applied to the copper 20 sub-floor 1 with the recesses V.

Det påførte lag 10 har en tykkelse D på ca. 10 ym, hviljet svarer til ca. 1-2 gange stegbredden SB og er flere gange den maksimale kornstørrelse K af hårdmaterialekornene H, som er ca. 1-3 ym. Volumeandelen af hårdmaterialekornene i lagmateri-25 alet er gennemsnitligt 30-40%, idet det dog ved en særlig udførelsesform forfremgangsmåden opnås, at den i stegområdet 5 og i det tilstødende øverste flankeområde er ca. 30-60 vol.%, men ved flankerne af fordybningerne V og på disses bund B er væsentligt mindre og her kun udgør ca. 10-20 vol%. Herved forhøjes 30 den oprindeligt prægede steg S med en ca·. dobbelt så høj lagtykkelse DS som tykkelsen D af det galvaniserede lag på bunden B af fordybningerne V. I praksis er forholdet mellem lagtykkelsen DS og tykkelsen D i ym f.eks. 10:5. Den forholdsvis høje koncentration af hårdmaterialepartiklerne på stegene S 35 opnås ved, at elektrolyten med de svævende hårdmaterialekorn H bevæges rastelængde R tangentialt til valseoverfladen med mindst samme hastighed som den, hvormed ionerne i elektrolyten bevæger sig hen over et hårdmaterialekorn med middel diameter.The applied layer 10 has a thickness D of approx. 10 µm, the rest equals approx. 1-2 times the step width SB and is several times the maximum grain size K of the hard material grains H, which is approx. 1-3 ym. The volume proportion of the hard material grains in the layer material is, on average, 30-40%, although in a particular embodiment, the process is achieved in that in the step region 5 and in the adjacent upper flank region it is approx. 30-60 vol.%, But at the flanks of the recesses V and on their bottom B is substantially smaller and here only constitutes approx. 10-20 vol%. This increases the initially marked step S by an approx. twice the layer thickness DS as the thickness D of the galvanized layer on the bottom B of the recesses V. In practice, the ratio of the layer thickness DS to the thickness D in µm is e.g. 10: 5th The relatively high concentration of the hard material particles on the steps S 35 is obtained by moving the electrolyte with the floating hard material grains H tangentially length R to the roller surface at at least the same rate as the ions in the electrolyte moving across a medium diameter hard material grain.

5 DK 167483 B15 DK 167483 B1

Den relative bevægelse af elektrolyten kan ske ved cirkulation af denne og/eller rotation af valsen.The relative movement of the electrolyte may occur by circulating it and / or rotating the roller.

I en foretrukken udførelsesform består det galvaniserede lag af sejt nikkel med indlejring af siliciumkarbid. Den be-5 lagte overflades farveoptagelsesvolumen svarer mindst til den graverede ubehandlede overflades og er ved de angivne forhold endog cav 20% større end den ubehandlede overflades farveoptagelsesvolumen .In a preferred embodiment, the galvanized layer consists of tough nickel with silicon carbide embedding. The color uptake volume of the coated surface corresponds at least to the engraved untreated surface and is even about 20% larger than the color uptake volume of the untreated surface at the specified conditions.

Fig. 4 viser et tværsnit gennem yderligere en udførelses-10 form for overfladen. Her er der på laget 10 med indlejrede hård-materialepartikler 11 galvanisk påført et hårdkromlag 11, i hvilket de yderste hårdmaterialepartikler er indlejret. Lagtykkelsen D1 af det yderste hårdkromlag svarer tilnærmelsesvist til den maksimale kornstørrelse, d.v.s. ca. 3 ym. Derved fås 15 en meget glat og slidstærk overflade, idet de yderst i nikkellaget lejrede hårdmaterialekorn indesluttes i kromlaget.FIG. 4 shows a cross-section through a further embodiment of the surface. Here, on the layer 10 with embedded hard material particles 11 is galvanically applied a hard chrome layer 11 into which the outer hard material particles are embedded. The layer thickness D1 of the outermost hard chrome layer corresponds approximately to the maximum grain size, i.e. ca. 3 ym. Thereby, a very smooth and durable surface is obtained, since the outermost layered hard material grains are enclosed in the chrome layer.

Fig. 5 viser stærkt forstørret et delbillede af et tværsnit gennem et stegområde med en belægning, der også kan være påført på en plan, ikke-graveret overflade. Det på bæremate-20 rialet T anbragte beskyttelseslag 10 består af et sejt indlejringsmateriale, nemlig af et i et basisk galvaniseringsbad påført nikkellag med deri indlejrede hårdmaterialekorn H, fortrinsvis af siliciumoxid. Lagtykkelsen svarer tilnærmelsesvis til to gange tre gange partikeldiameteren, og hårdmaterialean-25 delen ligger volumemæssigt på ca. 20-50% af laget. De sidst indlejrede hårdmaterialekorn H rager med en del af deres diameter ud fra overfladen af nikkellaget 10. Beskyttelseslaget 10, der er slidstærkt slagfast, men er ru på grund af de udragende hårdmaterialekorn H er fordelagtigt udglattet og be-30 skyttet mod kemisk og fintkornet abrasivt slid ved hjælp af et hårdkromlag 11. Det har vist sig, at kromet i det sure bad ikke giver huldannelser rundt om hårdmaterialepartiklerne H og ikke danner spidser eller forhøjninger oven over partiklerne.FIG. Figure 5 shows a greatly enlarged sectional view of a cross-section through a riser region with a coating that may also be applied to a flat, non-engraved surface. The protective layer 10 applied to the support material T consists of a tough embedding material, namely a nickel layer applied to a basic galvanizing bath with hard material grains H embedded therein, preferably of silica. The layer thickness corresponds to approximately three times the particle diameter, and the hard material portion is in volume of approx. 20-50% of the layer. The last embedded hard material grains H protrude with a portion of their diameter from the surface of the nickel layer 10. The protective layer 10, which is durable impact-resistant but rough due to the protruding hard material grains H is advantageously smoothed and abrasion-resistant against chemical and fine grain. wear by means of a hard chrome layer 11. It has been found that the chromium in the acid bath does not give hollow formations around the hard material particles H and does not form tips or elevations above the particles.

Farveoverførselsvalsens glatte overflade giver yderligere 35 den fordel, at trykmaskinernes rakler ikke slides så hurtigt, hvilket igen forbedrer valsernes levetid.The smooth surface of the color transfer roller further provides the advantage that the presses of the printing machines do not wear out as quickly, which in turn improves the life of the rollers.

Til opnåelse af en ensartet fordeling af hårdmaterialepartiklerne H over overfladen af en farveoverførselsvalse og 6 DK 167483 B1 til opnåelse af en relativt forøget koncentration af hårdmate-rialepartiklerne H på stegene i forhold til flankerne og bundområderne af fordybningerne hænges valsen lodret ned i det konstant cirkulerede galvaniseringsbad og drejes fortrinsvis lang-5 somt i dette.In order to obtain a uniform distribution of the hard material particles H over the surface of a color transfer roller and to obtain a relatively increased concentration of the hard material particles H on the steps relative to the flanks and the bottom areas of the depressions, the roller is suspended vertically in the continuous circular bath. and preferably rotated slowly therein.

For at holde hårdmaterialepartiklerne svævende indledes der periodisk en trykluftboblestrøm ved bunden af badet.To keep the hard material particles afloat, a compressed air bubble stream is periodically introduced at the bottom of the bath.

Følgende driftsbetingelser for en farveoverførselsvalse med et 70 ym raster har vist sig at være fordelagtige: 10 - Omkredshastighed 120 mm/sek, badtemperatur 55°C, galvani- 2 seringsstrømtæthed 2 A/dm af overfladeprojektionen, d.v.s. uden hensyn til den af graveringen forårsagede forstørrelse af overfladen, basisk nikkelbad.The following operating conditions for a color transfer roller with a 70 µm screen have been found to be advantageous: 10 - Circuit speed 120 mm / sec, bath temperature 55 ° C, galvanizing current density 2 A / dm of surface projection, i.e. regardless of the engraving of the surface, basic nickel bath caused by the engraving.

15 - Badtemperatur 55° C, strømtæthed 35 A/dmz af overfladeprojektionen, surt krombad. 115 - Bath temperature 55 ° C, current density 35 A / dmz of surface projection, acid chrome bath. 1

Claims

Color transfer roller, in which outer casing layer (1) is formed with grooves (V) and galvanically coated with a protective layer (10) of a durable material, characterized in that the applied protective layer (10) consists of a tough metal, in which are hard material alloy grains (H) with a grain size of approx. 1-3 µm, and the protective layer has a thickness equal to 1-3 times the grain size.

Color transfer roller according to claim 1, characterized in that the volume ratio of the hard material grains (H) in the area of roasting (S) between the recesses (V) is 30-60% and in the area between the sides and the bottom (B) of the recesses (V) is 10. -30% of the embedding layer material. 15

Color transfer roller according to claim 1 or 2, characterized in that the protective layer (10) in the region of the steps (S) has a layer thickness (DS) which corresponds to 1-2 times the breadth width (SB) and that the protective layer at the bottom has a 20 thickness (D) which is approx. half the layer thickness (DS).

Color transfer roller according to any of the preceding claims, characterized in that the hard material grains (H) consist of silicon carbide, silicon nitride, corundum or tungsten carbide, diamond or mixtures thereof. Color transfer roller according to any one of claims 1-4. characterized in that the layer thickness (DS) is 10 m. 2 Color transfer roller according to any one of the preceding claims, characterized in that the protective layer (10) of the tough metal material with the embedded hard material grains (H) is a first protective layer, which is galvanically applied to a further layer (11) consisting of a durable material, preferably hard chromium, than the first protective layer (10), and whose layer thickness (D1) corresponds approximately to the grain size of the hard material grains (H), and preferably the layer thickness (D1) of the hard chrome layer is 1.5-3 microns.

7. A method of producing a durable coating wherein galvanically applied to a first protective layer (10) of a tough metal from an electrolyte and including in the protective layer (10) hard material particles (H) kept floating in the electrolyte and the protective layer (10) has a thickness equal to approx. 1-3 times the grain size of the hard material particles (H), characterized in that a further layer (11) of a metal material with a greater hardness than the hardness of the tough metal layer of the first protective layer (10) is galvanically applied to the first protective layer (10). a layer thickness (D1) corresponding to approx. 0.5-1 times the grain size of the hard material particles (H).

Process according to claim 7, characterized in that the tough metal is separated by a basic nickel bath and that the hard material particles (H) consisting of silicon carbide and having a grain size of 1-3 µm are kept circulating in the nickel bath in such a circulation. concentration, that the hard material volume proportion in the protective layer is at approx. 30-40 1 ° r and that the metal material of the second layer (11) is separated as hard chromium by an acidic chromium bath. Method according to claim 8, characterized in that, for coating a color transfer roller (1), indentations (V) having a spacing (R) in its surface are embossed that the nickel bath is moved at such a speed across the surface that it is deposited. at least one break distance during the time during which the ions caused by the galvanizing current travel a distance corresponding to a grain diameter with the surface and that the velocity of the nickel bath relative to the roller surface is obtained by circulating the nickel bath and / or a movement of the color transfer roller. (1) in the nickel bath, whereby preferably the color transfer roller (1) is placed in the nickel bath with its roller axis oriented vertically and then rotated about the roller axis.

Method according to claim 9, characterized in that the color transfer roller (1) is rotated in the nickel bath at a roller circumference speed of 120 mm / sec. and kept at a temperature of approx. 55 ° C, and the galvanizing current density o is 2 A / dm of the projected surface, and preferably the nickel bath is periodically blown through with an air-bubbled stream, 10 and the color transfer roller (1) is rotated in the chrome bath at a roller circumference speed of 120 mm / sec. that the chrome bath temperature is kept at 55 ° C and that a galvanizing 2 current of 35 A / dm is used.