DE2045296A1 - Method and tool for embossing the surface of plastics, paper, metal foils and similar materials - Google Patents

Description

Sept. 10, 1970 Bl / Am

Stauffer Chemical Company, Dobbs Ferry, N.Y. 10322, USA

Method and tool for embossing the surface of plastics, paper, metal foils and similar materials

The present invention relates to a new and improved embossing tool, such as a roller, a plate, a stamp or the like. This tool, for example a roller, is obtained by electrolytic bollarding of the surface of a relief roller, whereby the sharpness of the engraving lines is increased by electroplating and electroplating the entire roll surface with a metal having a high or medium compensation or leveling effect, for example, by depositing copper, as well as by el- j NEN second electroplating in which an old metal lower Vlvelllerwlrkung, as chromium, is applied as a top layer. With the new and improved tool produced in this way, delicate and sensitive patterns of an original can be reproduced, with high fidelity being achieved in the reproduction.

New methods have been used in the industry for many years and processes are sought with which rollers, plates, stamps or other tools for embossing, graining, scars, etc.

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create and can be reproduced exactly in order to apply relief patterns, structures or grains of the best quality and appearance on a suitable substrate or background, here on paper, leather ₃ artificial leather, plastics, e.g. thermoplastics, synthetic fibers, vinyl products, on a metal foil or the like . Unfortunately, these Yersuche met with limited success because the copy or the result in general tk common did not have the required details and the desired reproduction accuracy. Therefore, details of natural objects, such as leaves, flowers, etc. would become indistinct or blurred, or, in other cases, when reproducing objects with a smooth surface, such as goat skin or patent leather, the copies were not as smooth as the original or the grain in fineness not comparable to the original. In some cases, additional procedural steps, such as polishing or other post-processing, were required, whereby even with such additional treatments no copies or products comparable in quality to the original were created, which had the same grain and appearance as the original. As soon as relatively small details were available, unsatisfactory products or reproductions resulted

Traditional methods by which the industry tried to create embossing effects on various materials,

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are, for example, machine engraving, etching and that electolytic forms. Machine-engraved embossing rollers, however, do not have the surface quality that is required is, for example, the brilliance and the fill of the grain of fine leather on vinyl products. The Elek * troforming, on the other hand, has not yet been developed to the point that the successful and accurate reproduction of a seamless Embossing roller or an embossing cylinder can be guaranteed | te as needed to faithfully reproduce the fine pattern and to emboss hars, for example in the shoe and Clothing industry, upholstery, etc. are necessary and be challenged

Thus, conventional embossing rollers can neither reproduce objects such as those made of leather, in particular goatskin, nor delicate figures or surface details. The normally achievable reproductions _

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of goatskin are & identified by stripes and a

very unclear, indeterminate overall impression · Such products do not have the elegant appearance of real goatskin. Furthermore, the replicas with unwanted lines and provide sharp edges and convey a feeling other sensation, such products do not even resemble that Appearance and elegance of good quality leather. It was therefore when using engraved embossing rollers or relief rollers

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it is not possible to obtain a top surface of the quality required, for example, to achieve the brilliance and the abundance of fine leather grain on vinyl products transferred to. So far it has not been possible to faithfully reproduce plates for embossing and scars in order to be able to use substrates, such as paper, leather, synthetic leather, plastic, metal foils and The like. Relief patterns or grains of high quality and fineness to raise.

The present invention includes a new and advanced one Process for modifying embossing rollers, plates, dies and similar tools in order to produce objects, the desired patterns or representations on their surfaces with an extremely high reproduction accuracy in every dimension. The use of the modified roller according to the invention leads to such an accurate and complete Replica that it is difficult to distinguish the copy from the original. The reproduction is so faithful to the reproduction, that even "weaving errors" are reproduced with high accuracy, if the original is or contains a fabric or a similar material. With the inventively achievable Embossing roller can therefore be reproduced so faithfully that there is hardly any limit to the type of pattern or objects Model exists, which the original may have. Any conventional or new pattern or model, be it natural

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Of origin or made by humans in some kind and catfish, can be reproduced, and not just in appearance, but also in terms of the impression it gives to the touch and the reflection caused by the structure or the grain With the modified relief roller, which is created by the method according to the invention, can also be in two- or three-dimensional Structure of any pattern or model can be reproduced, | just as you would on the surface of a cloth, an upholstery fabric, a table runner, on leather, on a reptile or animal skin, on wood, on carpet, on ruffled fabrics Surfaces, on linoleum and the like.

With the method according to the invention, a new and improved relief roller is created, wherein a machine-engraved or electrolytically formed roller is subjected to a combination of process steps, namely (1) an electrolytic polishing process, followed by a (2) plating process with a shiny metal which is characterized by a high or medium leveling or leveling effect in order to achieve both lightening and smoothing of the roller. Suitable metals are, for example, copper, iron, nickel or the like. A coating of a metal with the aforementioned smoothing and brightening effect is thus obtained over the entire surface of the embossing roller. This is followed by (J) a second plating or coating of the roller

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a top layer, the second plating suitably by using a metal with a relative to the first plating metal lower leveling effect, such as Chrome or nickel. The second plating results in a hard coating that is resistant to corrosion and erosion while at the same time the structure or grain of the desired end product is improved *

The order of the aforementioned process steps is not critical, since the electroplating with a small one Metal having a compensating effect can precede the electroplating process, in which a metal with a strong Leveling effect is used. These steps can then the electrolytic polishing follows.

The shape and structure of the embossing rollers, plates

or stamps for the new method according to the invention used is not critical. Rather, it can be any roller, any plate or any stamp or any similar one Tool in any suitable form can be used to create the desired grain or texture on the to transfer material to be embossed. The roller, the plate or the stamp can be made from a variety of materials including ferrous or non-ferrous metals,

Aluminum,
like / aluminum alloys ooä »exist. The advantages of aluminum rollers are that these rollers are better

Heat transfer, easier machining

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availability and lighter weight than steel rollers. Further It is also possible to take advantage of plastic rollers that have a metal layer on the surface. For example, plastic rolls have been made from polyvinyl chloride, solid urethane, and the like.

The engraving of the embossing rolls, plates, stamps and the like _e g is done by conventional methods ,, and it is not important to the success and impact of the process erfindungsgeiaäßen what particular method is used. The embossing tools can therefore be engraved in various ways, for example by hand, by machine, chemically or photochemically.

By using the method according to the invention, it is now surprisingly possible to obtain a modified roller, plate or the like with which a natural grain * can be successfully applied to paper, aluminum foil, plastics such as polypropylene, urethane, cellulose, synthetic fabrics or the like a material such as wood can be applied. It is surprising that the rollers modified according to the invention are suitable for all materials that can be embossed, regardless of whether they are artificial or natural materials. The roller according to the invention can therefore be used, for example, to replicate goatskin, wherein

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roan receives products that are characterized by their brilliance, their natural reproduction and the pleasant impression they make when "feeling" or "touching". The product has the appearance of just processed skin. If an electrolytic Polleren was conducted to seek to improve the cash by conventional embossing rollers recoverable _T appearance of the products, a certain appearance improvement was. However, as soon as attempts were made to mimic the appearance of natural leather, for example, electrolytic polishing resulted in products that did not have the desired gloss and did not have the feel of natural leather when "touched". Furthermore, these electrolytically polished products lacked the desired fine structures and details that characterize natural goatskin. The present invention therefore represents an important technical improvement, since it eliminates the tile parts that had previously been used in relief rollers. The new and improved process of the invention involves a combination of process steps. This combination consists of (1) electrolytic polishing of the relief roller, (2) modification of the roller by means of a gloss plating with a metal and (3) a second metal plating process. In the first plating process, a thin and shiny metal, which has a high or medium leveling effect, is generally applied to the surface of the roller. Suitable metals are

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for example copper, bickel or iron. It has shown* that copper is most beneficial. In the second plating process will generally be a metal with an im. Compared to the metal of the first plating, smaller compensation effect, such as * chromium or nickel are used.

Electrolytic polishing takes place in a conventional manner

and includes anodic treatment or anodizing of the Orphan, creating both a smoothing and a lightening is achieved. The electroplating processes used are also conventional. The rollers are used as Cathodes used in an electrolytic bath. Electroplating increases the surface properties of the Rollers, plates, stamps, etc., so that these tools can handle the Giving material that is to be embossed a shiny, leather-like appearance. In the electroplating can any conventional suitable electrolyte can be used, As noted above, there are multiple plating steps intended to achieve the desired surface characteristics comparable to the original material. For example, in the production of an embossed vinyl material that has the properties of smooth goatskin should have what, for example, in the shoe industry It is very desirable to do the first plating using a high or medium metal

with. .

Compensation effect, for example / copper, carried out, while for the second plating. - process a metal with

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less compensation effect, such as chrome, is provided.

When using the method according to the invention, one obtains a modified roller or a plate or a stamp or a tool with which it is possible, unusual To produce structure or grain effects, in particular those that require a fine and thin pattern on various substrates or surfaces, e.g. on Viny! Materials. Ss is therefore possible for the first time, from to obtain a replica of a grained surface that is lifelike and also corresponds extremely precisely to the original in terms of its dimensions of the roller modified according to the invention insofar as the engraving devices are not a limitation according to the invention regarding the shape, size or type of the sample or model.

The following serves to further explain the invention Example:

example

An 18] 5 cm (6 inch) roller was fitted with a Engraving of the grain of a first-class goatskin. The embossing that has been accessible to date on vinyl chloride materials

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were unsatisfactory since. the product through a blunt Plastic appearance was marked. Also found always have tool marks including parallel lines on the end product. Although there are some improvements in the grain of the product by electrolytic foiling the finished goods could still be reached not in the grain and structure or grain with natural Goatskin can be compared.

From the relief roller made of conventional steel, such as such according to the US standard SAE 1035, the metals were removed with which it had previously been plated. The roller was then hung in a steel-lined container known as the Cathode served while the roller was connected as an anode.

Although the preferred electrolyte is phosphoric acid and chromic acid Any electrolyte suitable for electrolytic conversion may be used depending on the cylinder metal or material Suitable for polishing steel, aluminum or copper is.

For electrolytic polishing, the roller becomes a solution exposed to the following composition under the specified conditions:

Sulfuric acid 15 %

* fWSW 1 8 1 9 ⁶⁵ *

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Chromic acid β j6

Water 14 %

Specific gravity 1.74

Anodic current density o, 054 to I _2, 09 A / £ cn

Treatment duration (min.) 5 to 20 (or as long as

as necessary)

The micro-roughness of the roller plate has been reduced. Some the high points of the metal surface have been removed.

After the electrolytic treatment, the roller was in a cyan bath with the following composition among the conditions mentioned in advance:

Gyan copper 22.4 S / 1 .6 Sodium cyanide 33.6 S / l B / l Sodium carbonate 14.95 g / l g / l Sodium hydroxide up to one 43 ⁰ C pH of 12 to 12 16.2 m A / cm ² Copper analysis 15.7 2.54 10 " ⁶ m Free cyanide 7.47 temperature 32.2 to Cathodic © current density 10, δ to Coating thickness 1.27 to

This copper coating turned into a shiny, acidic copper Electrolytically applied, whereby for the plating bath; the following composition or conditions were chosen

Copper sulfate 224 g / l

Sulfuric acid (liquid) 41 g / l

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Chloride ions 30 rag / l

ÜBAC - Supplementary 0.75 weight ^

ÜBAC - Rl -Additional 0.25 weight- #

Temperature '32, S ⁰ C.

Cathodic current density 108 mA / cm

Bath movement air at about 305 cur per minute

ρ
and per cm on the surface of the

Solution I.

Coating thickness 25.4 to 508 χ 10 ** ⁶ m

The electrolyte was stirred gently in order to keep the contact surface free from hydrogen bubbles.

It is noteworthy that in practice there is only a thin layer of copper is required.

A top layer of chrome was put on the shiny copper surface deposited, with a usual hard chrome bath as follows Composition and conditions used:

Chromic acid 246.5 g / l

Sulfuric acid 2.465 g / l

Bath ratio CrO ₅ ZHgSO ^ * 100: 1

Temperature 43 to 49 ⁰ C

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Cathodic current density 0.755 - 1 * 62 mA / cm

Coating thickness 12.7 x 10 " ta

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The plating bath determines the leveling effect, that is, the maturity of the deposit in sunken areas bsw. in depressions.

This when using a modified roller, which by the previous continuous process steps of the electrolytic Polishing and electroplating, the resulting product is characterized by its brilliance, Reproduction of naturalness and luster and "feels" like goatskin. The product has an elegant appearance and resembles in every detail the appearance and the Grain of goat leather

The rollers, stamps, tools and the like, can also 3 any material with a conductive surface.

The embossing rollers, stamps or VJerkzeuge can also be used for substrates or bases made of many materials are used, for example for substrates Plastics, paper, wood, metal and the like. After all, there are various substances as electrolytes suitable.

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Claims (1)

Claims 1. Tool, such as a relief roller, plate, stamp or similar, for reproducing a fine-meshed, grained, grained or similar pattern with high reproduction accuracy on a substrate material, characterized in that this is characterized by a λ drive is made that the combination of several Contains process steps, namely electrolytic Polishing of the tool surface, electroplating or coating of the tool surface with e, inera brightening metal that has a high to medium leveling effect, and with a metal that compared to the aforementioned metal, a lower compensating effect having" 2. Tool according to claim 1, characterized in that " this by electrolytic polishing of the tool surface, by electroplating the polished Surface with a »brightening metal, which has a high to medium leveling effect, as well as is made by a second electroplating with a metal that has a lower leveling effect having. 109817/1819 8ADORtGiNAL Tool according to claim 2 _P characterized in da3 this is electroplated first with copper, nickel or iron. Tool according to Claim 2, characterized in that, after the electrolytic polishing, it is subjected to a bright pre-copper plating in an alkaline cyanide medium _{or the like} 5. Tool according to claim 2, characterized in that that the second coating or electroplating is carried out by contacting with chromium or nickel. Process for the treatment of the engraved surface of an original stencil, which is intended for reproducing a fine-meshed or grained, grained or similar template with high reproduction accuracy on a suitable substrate or base area, characterized in that this surface is subjected to a combination of different process steps einera electrolytic polishing of the surface, an electroplating or ₀ coating the surface with a brightening metal having a high to medium 'Aüigieichswirkung, 109817/1819 ft as well as electroplating with a metal, ■ whose compensation effect is ¹ - lower _o 7. The method according to claim 6, characterized in that dl © surface of the original stencils first electrolytically polished and then this polished g Surface electroplated with a brightening metal that has a high to medium leveling effect, and that a plating or a galvanic coating is carried out with a metal having a lower leveling effect will. 8 "Method according to claim J _9, characterized in that a roller, a plate or a stamp with an engraved surface is provided as an original template. 9 ο method according to claim J ₉ . characterized in that a plastic, fabric, paper, metal foil or leather is used as the background or »substrate material. -.-.... 109817/1819 IQe method according to claim 7> characterized in that the compensating effect is brought about by electroplating with copper or iron ₀ Ho method according to claim 1 _s, characterized in that the second plating process is effected by tinting with chromium or nickel » 12ο Method according to claims 7 to 11, characterized in that the structure, grain and the effect of smooth goat leather or glossy leather is given to a vinyl material, namely by embossing the surface of a cylinder with smooth goat grain by electrolytic Bollarding of the roller surface by pre-copper plating ^the polished roller, by subsequent electroplating with a gloss of copper in order to achieve a coating of high toughness, brightness and hardness, then by electroplating with chrome and finally by embossing the vinyl material with the material produced or produced in this way. machined roller. IJo method according to claim 12, characterized in that the electrolytically polished roller before electroplating is pre-coppered with copper in an alkaline Zyanld ~ 8ad. 109817/1819