MXPA98005561A - Process for applying protective and decorative coating on an artic - Google Patents

Abstract

A method for depositing a protective and decorative multilayer coating on an article comprising first depositing at least one coating layer on the article by electroplating, removing the electroplated article from the electroplating bath and air-drying it to produce a surface without spots , and then depositing, by physical vapor deposition, at least one coating layer on the electroplated article. The electroplating layers are selected from copper, nickel and chromium. Physically deposited vapor layers are selected from non-precious refractory materials, non-precious refractory metal alloys, non-precious refractory metal composites, and non-price metal alloy composites.

Description

PROCESS TO APPLY DECORATIVE PROTECTIVE COAT ON AN ARTICLE The present invention relates to a method of applying protective and decorative coatings to articles.

Ant -. Ced ---. NtQa gives the Invention It is known in the art to provide an article such as, for example, a bronze key or a lock with a multilayer coating by depositing a first coating layer or series of coating layers by electroplating and then depositing a second coating layer or series of coating. coating layers on the electroplastic layer by physical vapor deposition. Such a multilayer coating provides abrasion and corrosion protection to the article, is decorative, and stabilizes any imperfections such as pitting or cracking in the article. Thus, for example, a bronze article having a double layer of nickel comprised of bright nickel and semi-gloss nickel electroplated thereon and a layer of zirconium nitride deposited on the double layer of nickel by physical vapor deposition is smooth, has improved the resistance to abrasion and corrosion, and has the color Ref: 27905 polished bronze.

In general, it is the deposited vapor layer that provides protection against abrasion and decorative appearance. However, the coating layer deposited by steam is generally very thin, typically in the range of about one to 20 millionths of an inch. Due to the thinness of the vapor deposited coating, any water stain or any other surface defects such as nickel or chromium stains or caused by the electroplating process are transparent and in fact are accentuated by the thin coating deposited by steam. Even light spots, spots or discolorations that are not visible to the naked eye in the electroplated article will become visible after the vapor deposited coating is applied.

In this way, it is currently necessary to thoroughly inspect, clean and dry each article as it leaves the electroplating bath. A conventional way of cleaning the electroplating articles is to subject the articles through an aqua-based cleaning system and to use nitrogen drying to dry the articles. This is very expensive and not always successful. Another method involves manual drying and individual cleaning of each item. This manual drying, while more effective than a nitrogen-based drying system, is very labor-intensive, and therefore also very expensive. Manual drying also involves the internal transport of the electroplated items which could result in the falling or striking of the articles against other objects with consequent damage to the articles.

It would be very advantageous if an efficient and effective drying method for electroplating articles were available which would eliminate the problems associated with currently used drying and cleaning methods. It is an object of the present invention to provide such a system.

Br-iv-i Daacription of the Invention The present invention comprises a method of applying a protective and decorative multilayer coating to an article. The method involves first applying at least one coating layer by electroplating. The electroplated article is then removed from the electroplating bath and air-dried for stain-free drying. The dried electroplated article is then placed in a vapor deposition chamber and at least one layer of vapor coating is deposited on the electroplated article.

The electroplating comprises applying at least one selected layer of copper, nickel and chromium. Copper electroplating includes alkaline copper electroplating and acid copper electroplating. Nickel electroplating includes bright nickel electroplating, semi-gloss nickel, and a double layer of nickel comprising bright nickel and nickel.

Before the electroplating, the article undergoes a vapor deposition process to apply at least one layer of thin coating deposited by steam on the electroplastic layer, the article is dried by air impulse to remove any wet stain or nickel or chrome stains. .

After air-pulse drying, at least one coating layer is deposited by physical vapor deposition on the surface of the electroplating layer. The vapor deposited layer or layers are selected from non-precious refractory metals, alloys of non-precious refractory metals, non-precious refractory metal composites and non-precious refractory metal alloy compounds. Non-precious refractory metal compounds and non-precious refractory metal alloy compounds include nitrides, oxides, carbides, carbonitrides and the reaction products of a refractory metal or refractory metal alloy, oxygen and nitrogen.

Brava Daacripción da loa Dibuñoa FIGURE 1 is a perspective cut-away view of a blow dryer or blown with air.

FIGURE 2 is a cross-sectional view, not to scale, of a portion of the substrate having the electroplating coating layers thereon; FIGURE 3 is a view similar to FIG. 2, but showing another embodiment of the invention with a different arrangement of the electroplating coating layers; FIGURE 4 is a cross-sectional view, not to scale, showing an arrangement of the layers physically deposited by steam.

FIGURE 5 is a view similar to FIG. 2, but showing another embodiment of the invention with a different arrangement of different physical vapor deposition layers; and FIGURE 6 is a cross-sectional view, not to scale, of a portion of the substrate having the electroplating and the physical vapor deposition coating layers thereon.

The method of this invention is especially characterized by providing a thin layer of deposited decorative and protective vapor on an electroplated sublayer which is free of defects or imperfections such as water spots, nickel spots or chromium stains. These defects or imperfections are in general due to stains that remain on the electroplated surface of the article as a result of the electroplating process, thin coating layer deposited by steam is applied on these stains these are accentuated extensively by this thin coating layer deposited by steam.

The method of the present invention comprises first depositing on at least a portion of the surface of an article at least one layer of electroplating coating, removing the electroplated article from the electroplating bath and subjecting it to pulsed air drying to remove any stain from the electroplating layer. the surface thereof and applying, by physical vapor deposition, at least one thin coating layer on the clean and dry electroplated surface.

Air pulse drying and an air pulse dryer are described in European Patent 0 486 711, the disclosure of which is incorporated herein by reference. The air pulse dryer is illustrated in Fig. 1. It briefly comprises a housing to a conventional circulating air dryer well known in the art. The fan, heating device and air circulation shutters correspond to known and conventional designs. A movable nozzle device is additionally installed on each side of the station. The nozzle device is equipped with small nozzle pipes, approximately 150 mm long, and is provided with 15 perforations corresponding to the width of the direction traveled. Each small nozzle pipe is supplied with air by means of solenoid valves. The solenoid valves are controlled by a microprocessor that allows the valves to be opened one after the other. The opening intervals can be adjusted between 20 and 100 ms via the control device. In case of large dryers, the valves open in groups, p. ex. From 6-8 small nozzle pipes, one pipe is always open. The nozzle devices move up and down in the opposite direction with an adjustable speed. The speed is normally approximately one to two runs per minute. The route corresponds to the height of the grid plus 50 mm above and below.

By means of the connection similar to the impulse of the individual small nozzle pipes to the supply of compressed air with a nominal pressure of six bar, 15 jets of air will result. These jets of air atomize the drops of water on the surface of the parts. Due to the repeated cleaning of the surface of the articles with the driving of the air jets and the staggering of the nozzle pipe to the nozzle pipe in the horizontal position, an air jet is generated for approximately 1 cm2 of surface.

The alternating passage and blowing of the air jets in the perforations, blind holes, slanted cuts and edges lead to a suction effect which removes the liquid even from the hollow spaces. This effect is very intense that even the extensive perforations in the hollow parts, the large interior spaces and the orifices dry well. When the parts of the grid are removed, no water flows out of the hollow spaces and in this way the quality of the surface is not spoiled by water spots.

A programmable control device allows a selection of the pulse frequency, the speed of the nozzle device, the number of open valves simultaneously, the number of strokes, and the temperature. These parameters can. be assigned to the articles to be treated. In a drying program, the speed and pulse frequency can be adjusted separately for each stroke. Large items with a large extension can be cleaned very quickly on the first trip with short air pulses. The main amount of attached drops of water are cleaned here.

During the following tours, the speed will be reduced automatically and the pulse frequency will be extended. Stronger air pulses and open valves for a longer period have a significantly better suction effect resulting in improved drying of the hollow spaces.

As the main amount of water is cleaned, p. ex. atomized, only a layer of thin adsorption subtracts to dry. Therefore, only short drying periods of two to five minutes are required at an air circulation temperature of 50 - 70 ° C.

Pulsed air drying provides spot-free drying. Thus the electroplated articles may have a thin coating by physical vapor deposition applied thereon without further cleaning or drying of the electroplated articles.

The article may be comprised of any electroplatable substrate, such as metal or plastic. The metals of which the article may be comprised include bronze, zinc, steel and aluminum. The electroplastic layer deposited by electroplating on at least a portion of the surface of the article may be comprised of one or more than one layer. Preferred electroplating layers include copper, which includes alkali copper and acid copper, nickel, which includes bright nickel and semi-gloss nickel and chromium.

If the article is comprised of bronze typically at least one layer of nickel and one of chromium are electroplated on the article, with the nickel layer being deposited directly on the surface of the article and the layer of chromium deposited on the layer of nickel. Bronze articles may also have a copper layer applied directly on the surface of the bronze. At least one layer of nickel is then electroplated onto the copper layer. A layer of chromium is then electroplated onto the nickel layer.

The nickel layer is deposited on at least a portion of the substrate surface of the article by conventional and well-known processes. These processes include using a conventional electroplating bath such as, for example, a Watt bath as the electroplating solution. Typically such baths contain nickel sulfate, nickel chloride and boric acid dissolved in water. All chloride electroplating solutions can also be used, sulfamate and fluoroborate. These baths may optionally include a number of well-known and conventionally used compounds such as equalizing agents, brighteners and the like. To produce the bright nickel layer at least one class I polish and at least one class II polish is added to the electroplating solution. Class I brighteners are organic compounds that contain sulfur. The class of type II brighteners are organic compounds that do not contain sulfur. The class of type II brighteners can also cause equalization and, when added to the electroplating bath without sulfur-containing type I brighteners, results in semi-gloss nickel deposits. These class I brighteners include naphthalene alkyl and benzenesulfonic acids, benzene and naphthalene di- and trisulfonic acids, benzene and naphthalene sulfonamides, and sulfonamides such as saccharin, ninil and allyl sulfonamides and sulfonic acids. Class II brighteners are generally unsaturated organic materials such as, for example, acetylenic or ethylenic alcohols, ethoxylated and propoxylated acetylenic alcohols, coumarins and aldehydes. These class I and class II brighteners are well known to those skilled in the art and are readily available commercially. These are described, in U.S. Pat. No. 4,421,611 incorporated herein by reference.

The nickel layer may be a monolithic layer comprising, for example, semi-gloss nickel or bright nickel; or it can be a double layer containing a layer comprising semi-gloss nickel and a layer comprising bright nickel. The thickness of the nickel layer is generally in the range of about 100 millionths (0.000100) of an inch, preferably about 150 millionths (0.000150) of an inch to about 3,500 millionths (0.0035) of an inch.

As is well known in the art before the nickel layer is deposited on the substrate the substrate is subjected to activation by being placed in a conventional and well known acid bath.

In one embodiment as illustrated in Fig. 2, the nickel layer 13 is actually comprised of two different nickel layers 14 and 16. The layer 14 is comprised of semi-glossy nickel while the layer 16 is comprised of bright nickel. This double deposit of nickel protection to enhanced protection against corrosion to the substrate of the base coat. The semi-gloss, sulfur-free plate 14 is deposited, by conventional electroplating processes, directly onto the substrate surface of the article 12. The substrate 12 containing the semi-gloss nickel layer 14 is then placed in a bright nickel electroplating bath and the bright nickel layer 16 is deposited on the semi-gloss nickel layer 14.

The thickness of the semi-glossy nickel layer and the bright nickel layer is an effective thickness to provide improved corrosion protection. In general, the thickness of the semi-gloss nickel layer is at least about 50 millionths (0.00005) of an inch, preferably at least about 100 millionths (0.0001) of an inch, and more preferably at least about 150 millionths (0.000150) of an inch. The upper limit thickness in general is not critical and is governed by secondary considerations such as cost. In general, however, a thickness of about 1,500 millionths (0.0015) of an inch, preferably about 1,000 millionths (0.001) of an inch, and more preferably about 750 millionths (0.000750) of an inch should not be exceeded. The bright nickel layer 16 in general has a thickness of at least about 50 millionths (0.00005) of an inch, preferably at least about 125 millionths (0.000125) of an inch, and more particularly at least about 250 millionths of an inch (0.00025). The upper thickness range of the bright nickel layer is not critical and is generally controlled by considerations such as cost. In general, however, a thickness of approximately 2,500 millionths (0.0025) of an inch, preferably approximately 2,000 millionths (0.002) of an inch, and more preferably approximately 1,500 millionths (0.0015) of an inch should not be exceeded. The bright nickel layer 16 also functions as an equalization layer which tends to cover or fill imperfections in the substrate.

In another embodiment of the invention as illustrated in FIG. 2 a layer of chromium 20 is electroplated onto the nickel layer 13. The chromium layer 20 could be deposited on the nickel layer 13 by conventional chromium plating techniques and well known. These techniques, together with various chromium electroplating baths, are exhibited at Brassard, "Decorative electroplating - A Process in Transition", Metal Finishing, pp. 105-108, June 1988; Za i, "chromium Palting", PF Directory, pp. 146-160; and U.S. Patent Nos. 4,460,438, 4,234,396 and 4,093,522, all of which are incorporated herein by reference.

Chromium electroplating baths are well known and commercially available. A typical chromium electroplating bath contains chromic acid or salts thereof, and catalyst ion such as sulfate or fluoride. The catalyst ions can be provided by sulfuric acid and its salts and fluorosilicic acid. The baths could be operated at a temperature of approximately 112 ° - 116 ° F. Typically in chromium plating a current density of approximately 150 amps per square foot is used, at approximately 5 to 9 volts.

The chrome layer in general has a thickness of at least about 2 millionths (0.000002) of an inch, preferably at least about 5 millionths (0.000005) of an inch and more preferably at least about 8 millionths (0.000008) of an inch. In general, the upper range of thickness is not critical and is determined by secondary considerations such as cost. However, the thickness of the chromium layer should generally not exceed about 60 millionths (0.00006) of an inch, preferably about 50 millionths (0.00005) of an inch and more preferably about 40 millionths (0.00004) of an inch.

In another embodiment of the invention, as illustrated in Fig. 3, especially when the article substrate is comprised of zinc or bronze, a copper layer 17 or layers are electroplated on at least a portion of the surface of article 12. Nickel layer 16 is then electroplated onto copper followed by chromium plating 20 on the nickel layer. The nickel layer could be a monolithic layer as illustrated in FIG. 3 and comprises, for example, bright nickel or it could be a double layer of nickel comprised of, for example, a bright nickel layer or a semi-gloss nickel layer . The copper coating 17 could be comprised of a monolithic copper layer or two different copper layers, for example, an alkaline copper layer on the surface of the article and an acid copper layer on the alkaline copper layer. In the embodiment illustrated in Fig. 3 the copper coating 17 is a monolithic copper layer comprising copper acid.

The copper electroplating process and the copper electroplating baths are conventional and well known in the art. They include the electroplating of acid copper and alkaline copper. They are described, inter alia, in U.S. Pat. Nos. 3,725,220; 3,769,179; 3,923,613; 4,242,181 and 4,877,450, the exhibits of which are incorporated herein by reference.

The preferred copper layer is selected from alkaline copper and copper acid. The copper layer could be monolithic and consist of a type of copper such as alkaline copper or copper acid, or it could comprise two different copper layers such as a layer comprising alkaline copper and a layer comprising copper acid llb.

The thickness of the copper layer is generally in the range of at least about 100 millionths (0.0001) of an inch, preferably at least about 150 millionths (0.00015) of an inch, preferably at least about 150 millionths (0.00015) of an inch to about 3,500 millionths (0.0035), preferably about 2,000 millionths (0.002) of an inch.

When a double copper layer comprised of, for example, an alkaline copper layer and an acid copper layer is present, the thickness of the alkaline copper layer is generally at least about 50 millionths (0.00005) of an inch, preferably at less about 75 millionths (0.000075) of an inch. The upper thickness limit in general is not critical. In general, a thickness of approximately 1,500 millionths (0.0015) of an inch, preferably approximately 1,000 millionths (0.001) of an inch should not be exceeded. The thickness of the acid copper layer is generally at least about 50 millionths (0.0005) of an inch, preferably at least about 75 millionths (0.00075) of an inch. The upper thickness limit in general is not critical. In general, a thickness of approximately 1,500 millionths (0.0015) of an inch, preferably approximately 1,000 millionths (0.001) of an inch should not be exceeded.

Some illustrative, non-limiting examples of the electroplated layers include substrate / nickel such as bright nickel / chromium, substrate / nickel semi-gloss / bright nickel / chromium, substrate / nickel such as bright nickel, substrate / nickel semi-gloss / bright nickel, substrate / copper such as acid / nickel copper such as bright nickel / chromium, substrate / alkaline copper / copper acid / nickel such as bright nickel / chromium, substrate / copper such as alkaline copper / semi-bright nickel / bright nickel / chromium, its t rat / copper at 1 ca 1 i no / copper acid / semi-bright nickel / bright nickel / chromium, substrate / copper such as acid / nickel copper such as bright nickel, substrate / copper such as alkali copper / semi-gloss nickel / bright nickel and substrate / alkaline copper / copper acid / semi-gloss nickel / bright nickel.

After the article has had the various electroplated coating layers, as exemplified above and in Figs. 2 and 3, deposited thereon by electroplating and then subjected to pulsed air drying to clean any light spots, spots, moisture or droplets and produce an electroplated article having an upper surface without spots. After completing the pulsed air drying the electroplated article is placed in a physical vapor deposition chamber and one or more thin coating layers are deposited by physical vapor deposition on the surface of the electroplated article.

The layers deposited by physical vapor deposition are metallic layers and are selected from non-precious refractory metals, alloys of non-precious refractory metals, non-precious refractory metal compounds and non-precious refractory metal alloy compounds. Non-precious refractory metal compounds include hafnium, tantalum and zirconium. The preferred refractory metals are titanium and zirconium, with zirconium being more preferred. Alloys of non-precious refractory metals include the alloys of the refractory metals mentioned above being the preferred binary alloys. Preferred binary alloys are zirconium binary alloys, binary alloys of zirconium and titanium being more preferred.

Non-precious refractory metals and metal alloy compounds include nitrides, oxides, carbides, carbonitrides of non-precious refractory metals and metal alloys. Also included among the non-precious refractory metals and metal alloy compounds useful in the present invention are the reaction products of a non-precious refractory metal or metal alloy, oxygen and nitrogen. Examples of these non-precious refractory metal compounds include zirconium nitride, zirconium oxide, zirconium carbide, zirconium carbonitride, reaction products of zirconium, oxygen and nitrogen, titanium nitride, titanium oxide, titanium carbonitride, products of reaction of titanium, oxygen and nitrogen, hafnium nitride, hafnium oxide, hafnium carbonitride, tantalum oxide, tantalum nitride, tantalum carbide and the like.

The reaction products of a non-precious refractory metal, such as for example zirconium, oxygen and nitrogen comprise zirconium oxide, zirconium nitride and zirconium oxynitride.

Illustrative non-limiting examples of non-precious refractory metal alloy compounds include zirconium-titanium nitride, zirconium-titanium oxide, zirconium-titanium carbide, zirconium-titanium carbonitride, hafnium-zirconium nitride, hafnium oxide, tantalum, tantalum-titanium carbide and reaction products of zirconium-titanium alloy, oxygen and nitrogen.

The layers comprised of refractory metals and alloys of refractory metals are deposited on at least a portion of the surface of the electroplated article by conventional and well known physical vapor deposition processes such as, for example, ion spray, vapor deposition by evaporation of cathode arc electrons and the like. Ion spray techniques and equipment are discussed, inter alia, in T. Van Vorous, "Planar Magnetron Sputtering; A New Industrial Coating Technique ", Solid State Technology, Dec. 1976, pp. 62-66; U. Kapacz and S.

Schulz, "Industrial Application of Decorative Coatings - Principle and Advantages of the Sputter Ion Plating Process", Vac. Coat., Proc. 34th Arn. Tech. Conf., Philadelphia, USA, 1991, 48-61; J. Vossen and W. Kern "Thin Film Processes II ", Academic Press, 1991, R. Boxman et al," Handbook of Vacuum Are Science and Technology ", Noyes Pub., 1995; U.S. patents Nos. 4, 162, 954 and 4, 591, 418, all the which are incorporated herein by reference.

Briefly, in the process of deposition by spraying the refractory metal such as anti-cathode Zirconium-titanium, which is the cathode and the substrate are placed in a vacuum chamber. The air inside the chamber is evacuated to produce vacuum conditions in the chamber. As an inert gas, such as Argon, it is introduced into the chamber. The gas particles are ionized and accelerated to the target to dislodge the titanium or zirconium atoms. The antipathous material dislodged is then typically deposited as a coating film on the substrate.

In the cathodic arc evaporation an electric arc typically of several hundred amperes is struck on the surface of a metal cathode such as zirconium or titanium.

The arc vaporizes the cathode material, which then condenses on the substrate to form a coating.

Reactive ion spray is generally similar to ion spray deposition except that a reactive gas such as, for example, oxygen or nitrogen which reacts with the displaced target material is introduced into the chamber. Thus, in the case where the zirconium nitride is a layer, the target is comprised of zirconium and the nitrogen gas is the reagent introduced into the chamber. To control the amount of nitrogen available to react with zirconium, the color of zirconium nitride can be made similar to bronze of various colors.

In general, more than one layer comprised of refractory metal, refractory metal alloy, refractory metal composite and refractory metal alloy compound is deposited in the electroplated article. Thus, for example, a layer comprised of refractory metal or refractory metal alloy such as zirconium is steam deposited on the electroplated article; a superimposed layer comprised of alternating layers of refractory metal or refractory metal alloy such as zirconium and refractory metal compound or refractory metal alloy compound such as zirconium nitride is then deposited on the zirconium layer; and a layer comprised of reaction products of a refractory metal alloy such as zirconium, oxygen and nitrogen is deposited on the superposed layer.

In another embodiment a layer comprised of a first refractory metal composite or refractory metal alloy compound, preferably a nitride, is vapor deposited on the refractory metal or refractory metal alloy layer. A layer comprised of a second refractory metal composite or composite of refractory metal alloy, preferably an oxide or the reaction products of a refractory metal or refractory metal alloy, oxygen and nitrogen, then steam is deposited in the first compound of refractory metal or refractory metal alloy composite layer.

In general, the refractory metal or refractory metal alloy layer has a thickness of at least about 0.25 millionths (0.00000025) of an inch, preferably at least about 0.5 millionths (0.0000005) of an inch, and more preferably at least about one millionth (0.000001). of an inch The upper range of thickness is not critical and is generally dependent on considerations such as cost. In general, however, the layer comprised of refractory metal or refractory metal alloy should not be thicker than about 50 millionths (0.00005) of an inch, preferably about 15 millionths (0.000015) inch, and more preferably about 10 millionth (0.000010) inch.

In general, the refractory metal or refractory metal alloy layer functions, inter alia, to improve the adhesion of a layer comprised of refractory metal compound, refractory metal alloy compound, reaction products of refractory metal or refractory metal alloy, oxygen and nitrogen to the electroplated article. Thus, the refractory metal or refractory metal alloy layer generally has a thickness that is less effective in improving the adhesion of a layer comprised of refractory metal compound, refractory metal alloy compound, and reaction products of a refractory metal. or refractory metal alloy, oxygen and nitrogen to the electroplated article.

In a preferred embodiment of the present invention the refractory metal layer is comprised of zirconium, titanium, or zirconium-titanium alloy, and is deposited by a physical vapor deposition process such as, for example, ion spray or vapor evaporation. electrons The layer comprised of refractory metal composite, refractory metal alloy compound or reaction products of refractory metal or refractory metal alloy compound, oxygen or nitrogen in general has a thickness that is at least about 2 millionths (0.000002) inch , preferably at least about 4 millionths (0.000004) of an inch, and more preferably at least about 6 millionths (0.000006) of an inch). The upper range of thickness in general is not critical and is dependent on considerations such as cost. In general, a thickness of about 30 millionths (0.00003) of an inch, preferably about 25 millionths (0.000025) of an inch, and more preferably about 20 millionths (0.000020) of an inch should not be exceeded.

This overall layer provides wear resistance, abrasion resistance and the desired appearance or color. This layer is preferably comprised of zirconium nitride or zirconium-titanium nitride alloy which has the color of bronze. The thickness of this layer is at least effective to provide wear resistance, abrasion resistance and the desired appearance or color.

In another embodiment of the invention a superimposed layer comprised of alternating layers of a non-precious refractory metal composite or a non-precious refractory metal alloy compound and a non-precious refractory metal or non-precious refractory metal alloy is deposited on the metal refractory or refractory metal alloy layer such as zirconium or zirconium-titanium alloy. An exemplary structure of this embodiment is illustrated in Fig. 4 where 22 represents the refractory metal or refractory metal alloy layer, preferably zirconium or zirconium-titanium alloy, 26 represents the superposed layer, 28 represents a layer of a composite of non-precious refractory metal or non-precious refractory metal alloy composite layer and 30 represents a non-precious refractory metal layer or a non-precious refractory metal alloy layer.

Non-precious refractory metals and alloys of non-precious refractory metals contain the layers 30 which include hafnium, zirconium, zirconium-titanium alloy, zirconium-hafnium alloy, and the like; preferably zirconium, titanium, or zirconium-titanium alloy; and more preferably zirconium or zirconium-titanium alloy.

Non-precious refractory metal compounds and non-precious refractory metal alloy compounds comprise layers 28 which include hafnium compounds, tantalum compounds, titanium compounds, zirconium compounds and zirconium-titanium alloy compounds; preferably titanium compounds, zirconium compounds or zirconium-titanium alloy compounds; and more preferably zirconium compounds or zirconium-titanium alloy compounds. These compounds are selected from nitride, carbides and carbonitrides, with nitride being preferred. Thus, the titanium compound is selected from titanium nitrides, titanium carbide and titanium carbonitride, with titanium nitride being preferred. The zirconium compound is selected from zirconium nitride, zirconium carbide and zirconium carbonitride, the preferred zirconium nitride being.

Overlay layer 26 generally has an average thickness of about 50 millionths (0.00005) of an inch to about one millionth (0.000001) of an inch, preferably of about 40 millionths (0.00004) of an inch to about two millionths (0.000002) of an inch, and more preferably from about 30 millionths (0.00003) of an inch to about three millionths (0.000003) of an inch.

Each of the layers 28 and 30 in general has a thickness of at least about 0.002 millionths (0.00000002) of an inch, preferably at least about 0.5 millionths (0.0000005) of an inch. In general, layers 28 and 30 should not be thicker than about 25 millionths (0.000025) of an inch, preferably about 10 millionths (0.00001) of an inch, and more preferably about 5 millionths (0.000005) of an inch.

One method of forming the overlay 26 is using ion spray electroplating to deposit a layer 30 of a non-precious refractory metal such as zirconium or titanium followed by reactive ion spray electroplating to deposit a layer 28 of a non-refractory metal nitride. precious such as zirconium nitride or titanium nitride.

Preferably the flow rate of nitrogen gas is varied (driven) during reactive ion spray electroplating between zero (nitrogen gas is not introduced) to the introduction of nitrogen at a desired value to form multiple alternating layers of metal 30 and metal nitride 28 in a superimposed layer 26.

The number of alternating layers of refractory metal 30 and layers of refractory metal composite 28 in the superposed layer 26 is generally at least about 2, preferably at least about 4, and more preferably at least about 6. In general, the number of alternating layers of refractory metal 30 and refractory metal composite 30 in superposed layer 26 should not exceed about 50, preferably about 40, and more preferably about 30.

In one embodiment of the invention, as illustrated in FIG. 4, the vapor deposited on the superposed layer 26 is a layer 32 comprised of a non-precious refractory metal compound or a non-precious refractory metal alloy compound, preferably a nitride, carbide, or carbonitride and more preferably a nitride.

The layer 32 is comprised of a hafnium compound, a tantalum compound, a titanium compound, a zirconium-titanium alloy compound or a zirconium compound, preferably a titanium compound, a zirconium-titanium alloy compound or a compound of zirconium and more preferably a zirconium compound or a zirconium-titanium alloy compound. The titanium compound is selected from titanium nitride, titanium carbide and titanium carbonitride, with titanium nitride being preferred. The zirconium compound is selected from zirconium nitride, zirconium carbonitride, zirconium carbide, with preferred zirconium nitride.

The layer 32 provides resistance to wear and abrasion and the desired color and appearance, such as, for example, polished brass. The layer 32 is deposited on the layer 26 by any of the conventional and well-known physical vapor deposition techniques such as reactive ion spray.

The layer 32 has a thickness at least effective to provide resistance to abrasion and / or bronze color. In general, this thickness is at least 2 millionths (0.000002) of an inch, preferably at least 4 millionths (0.000004) of an inch, and more preferably at least 6 millionths (0.000006) of an inch. The upper range of thickness in general is not critical and is dependent on considerations such as cost. In general, a thickness of about 30 millionths (0.00003) of an inch, preferably about 25 millionths (0.000025) of an inch, and more preferably about 20 millionths (0.000020) of an inch should not be exceeded.

Zirconium nitride is the preferred coating material as it more closely provides the appearance of polished bronze.

In one embodiment of the invention, as illustrated in FIG. 4, a layer 34 comprised of the reaction products of a non-precious refractory metal or metal alloy, a gas containing oxygen such as oxygen and nitrogen is deposited on layer 32. The metals that could be employed in the practice of this invention are those which are capable of forming metal oxide and a metal nitride under appropriate conditions, for example, using a reactive gas that contains oxygen and nitrogen. The metals could be, for example, tantalum, hafnium, zirconium, zirconium-titanium alloy and titanium, preferably titanium, zirconium-titanium and zirconium alloy and more preferably zirconium and zirconium-titanium alloy.

The reaction products of metals or metal alloys, oxygen and nitrogen generally contain metal or metal alloy oxide, metal or metallic alloy nitride and metal or metallic alloy oxynitride. Thus, for example, the reaction products of zirconium, oxygen and nitrogen comprise zirconium oxide, zirconium nitride and zirconium oxynitride.

The layer 34 may be deposited by well known and conventional physical vapor deposition techniques, which include reactive ion spray of a pure metal antipatho and a gas or an anthocyte composed of oxides, nitride and / or metals.

These metal oxides and metal nitrides including zirconium oxide and zirconium nitride alloys and their preparation and deposition are conventional and well known and are disclosed, inter alia, in U.S. Pat. No. 5,367,285, the disclosure of which is incorporated herein by reference.

The reaction products of metal, oxygen and nitrogen containing the layer 34 in general have a thickness of at least about 0.1 millionths (0.0000001) of an inch, preferably at least about 0.15 millionths (0.00000015) of an inch, and more preferably at least about 0.2 millionth (0.0000002) of an inch. In general, the metallic oxynitride layer should not be thicker than about one millionth (0.000001) inch, preferably about 0.5 millionth (0.0000005) inch, and more preferably about 0.4 millionth (0.0000004) inch.

In another embodiment, as illustrated in FIG. 5, instead of the layer 34 comprised of the reaction products of a refractory metal. or refractory metal alloy, oxygen and nitrogen deposited on the layer 32 a layer 36 comprised of a non-precious refractory metal oxide or non-precious refractory metal alloy oxide is applied by physical vapor deposition on the layer 32. refractory metal oxides and the refractory metal alloy oxides of which the layer 36 is comprised include, but are not limited to, hafnium oxide, tantalum oxide, zirconium oxide, titanium oxide, and zirconium oxide titanium, preferably titanium oxide, zirconium oxide, and zirconium titanium alloy oxide, and more preferably zirconium oxide and zirconium titanium alloy oxide.

The layer 36 has a thickness of at least about 0. 1 millionths (0.0000001) of an inch, preferably at least about 0.15 millionths (0.00000015) of an inch, and more preferably at least about 0.2 millionths (0.0000002) of an inch. In general, the metal or metallic alloy oxide layer 36 should not be thicker than about 2 millionths (0.000002) of an inch, preferably about 1.5 millionths (0.0000015) of an inch, and more preferably about one millionth (0.000001) of an inch .

Fig. 6 illustrates an article substrate 12 having a layer of bright nickel 16 electroplated on its surface and an electroplated chromium layer 20 on the bright nickel layer 16. On the electroplated chromium layer they are deposited by physical vapor deposition , after the substrate of article 12 having the electroplated layers 16 and 20 thereon has been subjected to air pulsed drying, the layer 22 comprised of zirconium, the superimposed layer 26 comprised of the alternating layers 28 and 30 comprised of, respectively, zirconium and zirconium nitride, layer 32 comprised of zirconium nitride, and layer 34 comprised of the reaction products of zirconium, oxygen and nitrogen.

In order that the invention can be more easily understood, the following example is provided. The example is illustrative and does not limit the invention.

Brass keys were placed in a thermal impregnation cleaner bath containing standard and well known soaps, detergents, deflocculants and the like which is maintained at a pH of 8.9 - 9.2 and at a temperature of 180 - 200 ° F for approximately 10 minutes . The bronze keys were then placed in a conventional ultrasonic alkaline cleaner bath. The ultrasonic cleaning bath has a pH of 8.9 - 9.2, it is maintained at a temperature of approximately 160 - 180 ° F, and contains the conventional and well-known soaps, detergents, deflocculants and the like. After the ultrasonic cleaning the keys were rinsed and placed in a conventional electroalkaline cleaning bath. The electrolytic cleaning bath is maintained at a temperature of about 140-180 ° F, at a pH of about 10.5-11.5, and contains the standard and conventional detergents. The keys were then rinsed twice and placed in a conventional acid activator bath. The acid activator bath has a pH of about 2.0-3.0, is at room temperature and contains an acid salt based on sodium fluoride. The keys were then rinsed twice and placed in a bright nickel electroplating bath for approximately 12 minutes. The bright nickel bath is generally a conventional bath which is maintained at a temperature of about 130-150 ° F, a pH of about 4.0, contains NiS04, NiCl2, boric acid and brighteners. A layer of bright nickel of an average thickness of approximately 400 millionths (0.0004) of an inch is deposited on the surface of the key. The bright nickel electrochapeadas keys rinsed three times and then placed in a conventional plating bath commercially available hexavalent chromium plating equipment using conventional chromium for about seven minutes. The hexavalent chromium bath is a conventional and well-known bath that contains approximately 32 ounces / gallon of chromic acid. The bath also contains conventional and well-known chromium plating additives. The bath is maintained at a temperature of about 112-116 ° F, and utilizes a sulphate / fluoride catalyst mixture. The ratio of chromic acid to sulfate is approximately 200: 1. A chrome layer of approximately 10 millionths (0.00001) of an inch is deposited on the surface of the bright nickel layer. The keys were rinsed completely is deionized water.

The electroplated keys are placed on a grid and the grid is moved through an air pulse dryer manufactured by LPW-Anlagen GmbH of Germany and described in European patent application EP 0486711 Al. The air dryer is equipped with a row of small nozzles that emit 80 psi air impulse jets. The dryer is maintained at a temperature of 130 ° F. The electroplated keys remain in the air pulse dryer for a total of 210 seconds, with the grid moving through the dryer two feet in five seconds. The grids remain motionless for 37 seconds and then move forward again. The last impulses for approximately 20 milliseconds. The keys are removed from the air pulse drier and placed in a cathodic arc evaporation electroplating container. The container is generally a cylindrical box containing a vacuum chamber that is adapted to be evacuated by means of pumps. A source of argon gas is connected to the chamber by an adjustable valve to vary the flow rate of argon in the chamber. In addition, a source of nitrogen gas is connected to the chamber by an adjustable valve to vary the nitrogen flow ratio in the chamber. A cylindrical cathode is mounted in the center of the chamber and connected to negative outputs of a variable power supply D.C. The positive side of the power supply is connected to the wall of the chamber. The cathodic material contains zirconium.

The electroplated keys are mounted on supports, 16 of which are mounted in a ring around the outside of the cathode. The entire ring rotates around the cathode while each bearing also rotates around its own axis, resulting in a well-called planetary motion that provides uniform exposure to the cathode for multiple keys mounted around each support. The ring typically rotates at several rpm, while each support performs several revolutions per revolution of the ring. The supports are electrically isolated from the chamber and provided with rotating contacts so that a bias voltage can be applied to the substrates during coating.

The vacuum chamber is evacuated to a pressure of approximately 5 x 10"3 millibar and heated to approximately 150 ° C.

The electroplated keys are then subjected to a high polarization arc plasma cleaning in which a (negative) polarization voltage of approximately 500 volts is applied to the electroplated keys while an arc of approximately 500 amperes is struck and maintained in the cathode. The duration of cleaning is approximately five minutes.

The argon gas is introduced at a sufficient rate to maintain a pressure of approximately 3 x 10'2 millibars. A layer of zirconium having an average thickness of approximately four millionths (0.000004) of an inch is deposited on the electroplated chromium keys for a period of three minutes. The cathodic arc deposition process comprises applying power D.C. to the cathode to reach a current flow of approximately 500 amps, introduce argon gas into the container to maintain the pressure in the vessel at approximately 1 x 10 ~ 2 millibar, and turn the keys in a planetary manner described above.

After the zirconium layer is deposited, the superimposed layer is applied to the zirconium layer. A flow of nitrogen is periodically introduced into the vacuum bed while the arc discharge continues at approximately 500 amps. The nitrogen flow rate is driven, e.g. ex. changed periodically at a maximum flow rate, sufficient to fully react the zirconium atoms arriving at the substrate to form zirconium nitride, and at a minimum flow rate equal to zero or some minor value not sufficient to fully react with all zirconium. The period of pulsation of the nitrogen flow is one to two minutes (30 seconds to one minute on, then off). The total time during the driven deposition is approximately 15 minutes, resulting in a stack of superposed layers with 10 to 15 layers of thickness of approximately one to 1.5 millionths of an inch each. The material deposited in the superimposed layer alternates between fully reactive zirconium nitride and zirconium metal (or substoichiometric ZrN with much lower nitrogen content).

After the superimposed layer is deposited, the flow rate of nitrogen is left at its maximum value (enough to form zirconium nitride that reacts completely) for a time of five to ten minutes to form a thicker "color layer" on the surface of the superimposed layer. After this the zirconium nitride layer is deposited, an additional flow of oxygen of approximately 0.1 standard liters per minute is introduced for a time of thirty seconds to one minute, while maintaining the flow rates of nitrogen and argon in its previous values. A thin layer of mixed reaction products is formed (zirconium oxynitride), with a thickness of about 0.2 to 0.5 millionths of an inch. The arc is consumed at the end of this last deposition period, the vacuum chamber is vented and the coated substrates are removed.

It is noted that in relation to this date, the best method known to the applicant to carry out the aforementioned invention, is that which is clear from the present description of the invention.

Having described the invention as above, the content of the following is claimed as property.

Claims (61)

1. A process for depositing a multilayer coating on at least a portion of a surface of the article, characterized in that it comprises: depositing by electroplating at least one layer of electroplating on at least a portion of the article to form an electroplated article; subjecting the article having at least one layer of electroplating to drying by pulses of air to dry the article and removing any liquid stain thereof; Y depositing by physical vapor deposition at least one layer in at least a portion of the electroplating layer.

2. The process of claim 1, characterized in that the electroplating comprises the electroplating of at least one selected layer of copper, nickel and chromium at least a portion of the surface of the article.

3. The process of claim 2, characterized in that at least one layer selected from refractory metal, refractory metal alloy, composed of the refractory metal, and composed of the refractory metal alloy is vapor deposited in at least a portion of at least one layer of electroplating.

4. The process of claim 3, characterized in that the refractory metal and the refractory metal alloy is selected from zirconium, titanium and zirconium-titanium alloy.

5. The process of claim 4, characterized in that the refractory metal and the refractory metal alloy is selected from zirconium and zirconium-titanium alloy.

6. The process of claim 3, characterized in that the refractory metal compound and the refractory metal alloy compound is selected from nitrides, carbides, carbonitrides, oxides and reaction products of refractory metal or refractory metal alloy, oxygen and nitrogen .

7. The process of claim 6, characterized in that the refractory metal compound and the refractory metal alloy compound is selected from nitrides, oxides and reaction products of refractory metal or refractory metal alloy, oxygen and nitrogen.

8. The process of claim 7, characterized in that the refractory metal compound and the refractory metal alloy compound is selected from zirconium nitride, zirconium oxide, reaction products of zirconium, oxygen and nitrogen, titanium nitride, oxide titanium, reaction products of titanium, oxygen and nitrogen, nitride of zirconium-titanium alloy, oxide of zirconium-titanium alloy, and reaction products of zirconium-titanium alloy, oxygen and nitrogen.

9. The process of claim 8, characterized in that the refractory metal compound and the refractory metal alloy compound is selected from zirconium oxide, zirconium nitride, reaction products of zirconium, oxygen and nitrogen, zirconium alloy nitride titanium, zirconium-titanium alloy oxide, and reaction products of zirconium-titanium alloy, oxygen and nitrogen.

10. The process of claim 7, characterized in that the electroplating comprises the electroplating of at least one copper-containing layer on at least a portion of the surface of the article to provide at least one layer of electroplating copper, electroplating in at least the layer that contains nickel in at least one layer of copper electroplating to provide at least one layer of nickel electroplating, and electroplating in at least one layer containing chromium in at least one layer of nickel electroplating to provide at least one layer of electroplating of nickel. chrome.

11. The process of claim 10, characterized in that at least one layer selected from refractory metal and refractory metal alloy is vapor deposited in at least a portion of the chromium electroplating layer.

12. The process of claim 11, characterized in that the refractory metal and the refractory metal alloy is selected from zirconium, titanium and zirconium-titanium alloy.

13. The process of claim 12, characterized in that the refractory metal and the refractory metal alloy is selected from zirconium and zirconium-titanium alloy.

14. The process of claim 13, characterized in that a coating of different materials comprising alternating layers of zirconium or zirconium-titanium alloy and zirconium nitride or zirconium-titanium alloy nitride is vapor deposited on the zirconium or zirconium alloy layer -titanium.

15. The process of claim 14, characterized in that a zirconium nitride or nitride of the zirconium titanium alloy is vapor deposited on the interleaved layer of different materials.

16. The process of claim 15, characterized in that a zirconium oxide or zirconium titanium oxide is vapor deposited on the zirconium nitride or nitride layer of the zirconium-titanium alloy.

17. The process of claim 15, characterized in that a layer containing the reaction products of zirconium or zirconium-titanium alloy, oxygen and nitrogen is deposited by steam on the zirconium nitride layer or zirconium-titanium alloy nitride .

18. The process of claim 13, characterized in that a layer containing zirconium nitride or nitride of the zirconium-titanium alloy is vapor deposited on the zirconium or zirconium-titanium alloy layer.

19. The process of claim 18, characterized in that a layer containing zirconium oxide or oxide of the zirconium-titanium alloy is deposited by steam > on the layer of zirconium nitride or zirconium-titanium nitride alloy.

20. The process of claim 18, characterized in that a layer containing the reaction products of zirconium or zirconium-titanium alloy, oxygen and nitrogen is deposited by steam on the zirconium nitride or nitride layer of the zirconium-titanium alloy.

21. The process of claim 1, characterized in that the electroplating comprises the electroplating of at least one layer selected from nickel and chromium on at least a portion of the surface of the article.

22. The process of claim 21, characterized in that at least one layer selected from refractory metal, refractory metal alloy, composed of the refractory metal, and composite of the refractory metal alloy i is vapor deposited3 in at least a portion of at least one electroplated layer.

23. The process of claim 22, characterized in that the refractory metal and the refractory metal alloy is selected from zirconium, titanium and zirconium-titanium alloy.

24. The process of claim 23, characterized in that the refractory metal and the refractory metal alloy is selected from zirconium and zirconium-titanium alloy.

25. The process of claim 22, characterized in that the refractory metal compound and the refractory metal alloy compound is selected from nitrides, carbides, carbonitrides, oxides and reaction products of refractory metal or refractory metal alloy, oxygen and nitrogen .

26. The process of claim 25, characterized in that the refractory metal compound and the refractory metal alloy compound is selected from nitrides, oxides and reaction products of refractory metal or refractory metal alloy, oxygen and nitrogen.

27. The process of claim 26, characterized in that the refractory metal compound and the refractory metal alloy compound is selected from zirconium nitride, zirconium oxide, reaction products of zirconium, oxygen and nitrogen, titanium nitride, oxide titanium, reaction products of titanium, oxygen and nitrogen, nitride of zirconium-titanium alloy, oxide of zirconium-titanium alloy, and reaction products of zirconium-titanium alloy, oxygen and nitrogen.

28. The process of claim 27, characterized in that the refractory metal compound and the refractory metal alloy compound is selected from zirconium oxide, zirconium nitride, reaction products of zirconium, oxygen and nitrogen, zirconium alloy nitride. titanium, zirconium-titanium alloy oxide, and reaction products of zirconium-titanium alloy, oxygen and nitrogen.

29. The process of claim 26, characterized in that the electroplating comprises the electroplating of at least one layer containing nickel in at least a portion of the surface of the article to provide at least one layer of nickel electroplating, and electroplating in at least one layer containing chromium in at least one layer of nickel electroplating to provide at least one layer of chromium electroplating.

30. The process of claim 29, characterized in that at least one selected layer of refractory metal and refractory metal alloy is vapor deposited in at least a portion of the chromium electroplating layer.

31. The process of claim 30, characterized in that the refractory metal and the refractory metal alloy is selected from zirconium, titanium and zirconium-titanium alloy.

32. The process of claim 31, characterized in that the refractory metal and the refractory metal alloy is selected from zirconium and zirconium-titanium alloy.

33. The process of claim 32, characterized in that a coating of different materials comprising alternating layers of zirconium or zirconium-titanium alloy and zirconium nitride or nitride of the zirconium-titanium alloy is deposited by steam on the zirconium or zirconium alloy layer -titanium.

34. The process of claim 33, characterized in that a zirconium or nitride of the zirconium-titanium alloy is vapor deposited on the layer of different materials.

35. The process of claim 34, characterized in that a zirconium oxide or zirconium titanium oxide is vapor deposited on the zirconium nitride or nitride layer of the zirconium-titanium alloy.

36. The process of claim 34, characterized in that a layer containing the reaction products of zirconium or zirconium-titanium alloy, oxygen and nitrogen is deposited by steam, on the zirconium nitride or zirconium alloy nitride layer. titanium.

37. The process of claim 32, characterized in that a layer containing zirconium nitride or nitride of the zirconium-titanium alloy is vapor deposited on the zirconium or zirconium-titanium alloy layer. 38. The process of claim 37, characterized in that a zirconium oxide-containing layer or oxide of the zirconium-titanium alloy is vapor deposited on the zirconium nitride layer or zirconium-titanium nitride layer. 39. The process of claim 37, characterized in that a layer containing the reaction products of the zirconium or zirconium-titanium alloy, oxygen and nitrogen layer is deposited by steam, on the zirconium nitride or nitride layer of the zirconium-titanium.

38. The process of claim 1, characterized in that at least one layer selected from refractory metal, refractory metal alloy, composed of the refractory metal, and composite refractory metal alloy is vapor deposited * in at least a portion of at least one electroplated layer.

39. The process of claim 38, characterized in that the refractory metal and the refractory metal alloy is selected from zirconium, titanium and zirconium-titanium alloy.

40. The process of claim 39, characterized in that the refractory metal and the refractory metal alloy is selected from zirconium and zirconium-titanium alloy.

41. The process of claim 38, characterized in that the refractory metal compound and the refractory metal alloy compound is selected from nitrides, carbides, carbonitrides, oxides and reaction products of refractory metal or refractory metal alloy, oxygen and nitrogen .

42. The process of claim 41, characterized in that the refractory metal compound and the refractory metal alloy compound is selected from nitrides, oxides and reaction products of refractory metal or refractory metal alloy, oxygen and nitrogen.

43. The process of claim 42, characterized in that the refractory metal compound and the refractory metal alloy compound is selected from zirconium nitride, zirconium oxide, reaction products of zirconium, oxygen and nitrogen, titanium nitride, oxide titanium, reaction products of titanium, oxygen and nitrogen, nitride of zirconium-titanium alloy, oxide of zirconium-titanium alloy, and reaction products of zirconium-titanium alloy, oxygen and nitrogen.

44. The process of claim 43, characterized in that the refractory metal compound and the refractory metal alloy compound is selected from zirconium oxide, zirconium nitride, reaction products of zirconium, oxygen and nitrogen, zirconium alloy nitride. titanium, zirconium-titanium alloy oxide, and reaction products of zirconium-titanium alloy, oxygen and nitrogen.

45. The process of claim 1, characterized in that at least one layer selected from refractory metal and refractory metal alloy s-e vaporizes, at least a portion of the electroplated article.

46. The process of claim 45, characterized in that the refractory metal and the refractory metal alloy is selected from zirconium, titanium and zirconium-titanium alloy.

47. The process of claim 46, characterized in that the refractory metal and the refractory metal alloy is selected from zirconium and zirconium-titanium alloy.

48. The process of claim 47, characterized in that a coating of different materials comprising alternating layers of zirconium or zirconium-titanium alloy and zirconium nitride or nitride of the zirconium-titanium alloy is deposited by steam on the zirconium or zirconium alloy layer -titanium.

49. The process of claim 48, characterized in that a zirconium or nitride of the zirconium-titanium alloy is deposited by the SODre v. Layer of different materials.

50. The process of claim 49, characterized in that a zirconium oxide or zirconium-titanium oxide is vapor deposited on the zirconium nitride or nitride layer of the zirconium-titanium alloy.

51. The process of claim 49, characterized in that a layer containing the reaction products of zirconium or zirconium-titanium alloy, oxygen and nitrogen is vapor deposited on the zirconium nitride or nitride layer of the zirconium-titanium alloy.

52. The process of claim 47, characterized in that a layer containing zirconium nitride or nitride of the zirconium-titanium alloy is vapor deposited on the zirconium or zirconium-titanium alloy layer.

53. The process of claim 52, characterized in that a layer containing zirconium oxide or oxide of the zirconium-titanium alloy is deposited by steam, on the zirconium nitride or zirconium-titanium nitride layer.

54. The process of claim 52, characterized in that a layer containing the reaction products of zirconium or zirconium-titanium alloy, oxygen and nitrogen deposits by vapor on the zirconium nitride or nitride layer of the zirconium-titanium alloy.

55. The process of claim 1, characterized in that the article contains metal or a metal alloy.

56. The process of claim 1, characterized in that the article contains bronze.

57. The process of claim 1, characterized in that the article contains zinc.

58. The process of claim 1, characterized in that the article contains plastic.

59. The process of claim 1, characterized in that the article is a key.

60. The process of claim 1, characterized in that the article is door lock hardware.

61. The process of claim 1, characterized in that the article is a lamp.