MXPA97000184A - Article with a protective coverage on me - Google Patents

Abstract

The present invention is an article that is coated with a multilayer coating comprising a layer of bright nickel deposited on the surface of the article, a layer of semi-gloss nickel deposited on the bright nickel layer, a layer of gold deposited on the layer of nickel. semi-bright nickel, a layer of ruthenium deposited on the gold layer, a refractory metal, preferably a zirconium leveling layer deposited on the ruthenium layer, and a refractory metal compound, preferably zirconium nitride, deposited on the layer of equalization of the refractory metal. The coating provides the color of the polished bronze to the article and also provides protection against abrasion and against corrosion.

Description

ARTICLE WITH A PROTECTIVE COAT ON THE SAME FIELD OF THE INVENTION The present invention is directed to metallic coatings of multiple layers, protective, for metal substrates.

BACKGROUND OF THE INVENTION It is a common practice with several brass or brass items such as lamps, table mats, candle holders, knobs and door handles and the like, first burnishing and polishing the surface of the item to achieve an intense shine and then apply a protective organic coating, such as one comprised of acrylics, urethanes, epoxies, and the like, on this polished surface. Although this system in general is completely satisfactory, it has the disadvantage that the burnishing and polishing operation, particularly if the article is of a complex shape, is intense in terms of the work performed. Also, known organic coatings are not always as durable as desired, particularly in outdoor applications where articles are exposed to the elements and ultraviolet radiation. For the Ref. 23835 therefore, it could be completely advantageous if brass or brass articles, or indeed other metal articles, could be provided with a coating which gives the article the appearance of highly polished brass or brass and which also provides resistance to wear and tear. protection against corrosion. The present invention provides such a coating.

BRIEF DESCRIPTION OF THE INVENTION The present invention is directed to a metal substrate having a multilayer coating placed or deposited on its surface. More particularly, it is directed to a metallic substrate, particularly bronze or brass, which has deposited on its surface multiple overlapping metallic layers of certain types of metals or of metallic compounds or metal alloys. The coating is decorative and protective, for example, it provides resistance against wear and corrosion. The coating simulates the appearance of highly polished brass or brass, that is, it has a color tone of bronze or brass. Accordingly, a surface of the article having the coating on it, simulates a surface of highly polished brass or brass.

A first layer deposited directly on the surface of the substrate is comprised of nickel. The first layer preferably consists of two different nickel layers such as a layer of semi-gloss nickel deposited directly on the surface of the substrate and a layer of bright nickel superimposed on the semi-gloss nickel layer. Placed on the nickel layer is a layer comprised of gold. This layer of gold is thinner than the nickel layer. On the gold layer is a layer comprised of ruthenium. On the ruthenium layer is a layer comprised of a non-precious refractory metal such as zirconium, titanium, hafnium or tantalum, preferably zirconium or titanium. A top layer comprised of a zirconium compound, a titanium compound, a hafnium compound or a tantalum compound, preferably a titanium compound or a zirconium compound such as zirconium nitride, is placed on the refractory metal layer , preferably the zirconium layer. The nickel, gold and ruthenium layers are preferably applied by electroplating. The refractory metal layer such as the zirconium layer and the refractory metal composite layer such as the zirconium compound layer are applied by vapor deposition such as by ion spray deposition.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a cross-sectional view of a portion of the substrate having the multilayer coating deposited on its surface.

DESCRIPTION OF THE PREFERRED MODALITY The substrate 12 can be any metal or metal alloy substrate such as copper alloys, steel, bronze, tungsten, nickel, and the like. In a preferred embodiment the substrate is brass or brass. The nickel layer 13 is deposited on the surface of the substrate 12 by conventional and well-known electroplating processes. These processes include the use of a conventional electroplating bath such as, for example, a Watts bath as the plating solution. Typically such baths contain nickel sulfate, nickel chloride, and boric acid dissolved in water. The chloride, sulphamate and fluoroborate plating solutions can also be used. These baths may optionally include a number of conventionally used and well known compounds such as leveling agents, brighteners, and the like. To produce the specularly bright nickel layer, at least one class I polish and at least one class II polish is added to the plating solution. Class 1 polishes are organic compounds that contain sulfur. Class II polishes are organic compounds that do not contain sulfur. Class II polishes can also cause homogeneous and uniform deposition and, when added to the plating bath without sulfur-containing class I brighteners, lead to semi-glossy nickel deposits. These class I brighteners include alkyl naphthalene and benzene sulphonic acids, benzene and naphthalene di- and trisulfonic acids, benzene and naphthalene sulfonamides, and sulfonamides such as saccharine, vinyl and allylsulfonamides and sulfonic acids. Class II polishes 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 polishes are well known to those skilled in the art and are readily available commercially. They are described, inter alia, in U.S. Pat. No. 4,421,611, incorporated herein by reference. The nickel layer is preferably comprised of a double layer containing a layer comprised of semi-gloss nickel and a layer comprised of bright nickel. The thickness of the nickel layer is generally in the range of about 0.0001004 inches (0.000100 inches), preferably about 0.000381 cm (0.000150 inches) to about 0.00889 cm (0.0035 inches). 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 a preferred embodiment as illustrated in the Figure, the nickel layer 13 is comprised of two different layers of nickel 14 and 16. The layer 14 is comprised of semi-glossy nickel while the layer 16 is comprised of bright nickel. This double nickel deposit provides improved corrosion protection to the underlying substrate. The semi-bright sulfur-free plate 14 is deposited, by conventional electro-plating processes, directly onto the surface of the substrate 12. The substrate 12 containing the semi-glossy nickel layer 14 is then placed in a bright nickel plating bath and the bright nickel layer 16 is deposited on the semi-gloss nickel layer 14. The thickness of the semi-gloss nickel layer and the bright nickel layer is of an effective thickness to provide improved protection against corrosion. In general, the thickness of the semi-gloss nickel layer is at least about 0.0000127 cm (0.00005 inches), preferably at least about 0.000254 cm (0.000100 inches), and more preferably at least about 0.000381 cm (0.00015 inches). The upper thickness limit in general is not critical and is governed by secondary considerations such as cost. In general, however, a thickness of about 0.00381 cm (0.0015 inches), preferably about 0.00254 cm (0.001 inches), and more preferably about 0.001905 cm (0.00075 inches), should not be exceeded. The bright nickel layer 16 generally has a thickness of at least about 0.000127 cm (0.00005 inches), preferably at least about 0.000318 cm (0.000125 inches), and more preferably at least about 0.000635 cm (0.000250 inches). The upper thickness range of the bright nickel layer n0 is critical and is generally controlled by considerations such as cost. In general, however, a thickness of about 0.00635 cm (0.0025 inch), preferably about 0.00508 cm (0.002 inch), and more preferably about 0.00381 cm (0.0015 inch) in size should not be exceeded. The bright nickel layer 16 also functions as a homogenous and uniform deposition layer which tends to cover or fill the imperfections in the substrate. Placed on the bright nickel layer 16 is a relatively thin layer of gold. The gold layer 18 may be deposited on the layer 16 by well-known and conventional gold deposition techniques. These techniques include but are not limited to plating, preferably electroplating techniques. Gold electroplating processes and baths are conventional and well known in the art. Some baths and gold plating processes are described in Gold Plating Techniques, F.H. Reed et al, Electro-Chemical Publications Limited, Scotland, 1974, and U.S. Pat. Nos. 4,377,448 and 4,082,622, all of which are incorporated herein by reference. Various types of gold electroplating solutions can be used, including solutions buffered with phosphate and solutions buffered with citrate. Two typical solutions are given right away.

KAu (CN) 2 20 g / 1 Optimum plating temperature is +65 degrees C KAu (CN), 20 g / 1 (NH) 4) 2HC6H50? 50 g / 1 The conductivity can be increased by adding (typically 50 g / 1) (NH,) "S0 ,. The optimum plating temperature is +65 degrees C. The gold layer generally has a thickness of at least about 0.000000635 cm (0.00000025 inches), preferably at least about 0.0000012 cm (0.0000005 inches) of an inch, and more preferably at less approximately 0.00000254 cm (0.000001 inches). In general, the upper thickness range is not critical and is determined by secondary considerations such as cost. However, the thickness of the gold layer in general should not exceed approximately 0.000127 cm (0.00005 inches), preferably 0.0000381 cm (0.000015 inches), and more preferably 0.0000254 cm (0.000010 inches). The ruthenium layer 20 is deposited on the gold layer 18 in a variety of well-known and conventional ways such as for example by plating, sputtering, vacuum deposition, and depositing the ruthenium metal as a finely divided dispersion in a vehicle. organic. The ruthenium is preferably deposited by plating, preferably by electroplating. The ruthenium electroplating processes and the plating baths are conventional and well known. They are described, for example, in The Journal of the Chemical Society of London, 1971 edition, page 839, by C.D. Burke and J.O. O'Meardi and Electrodeposition of Alloys, Vol. II, pp. 4-29, Abner Brenner (1963). Ruthenium electroplating baths can be acidic or non-acidic. Some exemplary examples of non-acid ruthenium electroplating baths are described in U.S. Pat. Nos. 4,297,178 and 4,507,183, arabs of which are incorporated herein for reference. Some illustrative examples of the acid ruthenium plating baths are described in U.S. Pat. No. 3,793,162, incorporated herein by reference. Some other ruthenium plating baths are described in U.S. Pat. Nos. 3,576,724 and 4,377,448, both of which are incorporated herein by reference. Ruthenium plating baths include nitrous salt baths and sulfamate baths. Ruthenium can be electroplated by the use of direct, continuous current densities, or by the use of pulsed current plating, that is, where a current is generated during a first period of time and is absent during a second period of time. time, the first and second periods of time recur cyclically. Ruthenium pulse current plating is described, for example, in U.S. Pat. Do not,. 4,082,622, incorporated herein by reference. The thickness of the ruthenium layer 20 is at least about 0.000005 cm (0.000002 inches), preferably at least about 0.0000127 cm (0.000005 inches), and more preferably at least about 0.0000203 cm (0.000008 inches). The upper thickness range is not critical and generally depends on economic considerations. In general, a thickness of about 0.000254 cm (0.0001 inches), preferably about 0.000127 cm (0.00005 inches), and more preferably about 0.0000635 cm (0.000025 inches) in size should not be exceeded. Placed on the ruthenium layer 20 is a layer 22 comprised of a non-precious refractory metal such as hafnium, tantalum, zirconium or titanium, preferably zirconium or titanium, and more preferably zirconium. The layer 22 serves, inter alia, to increase or improve the adhesion of the layer 24 to the layer 20. The layer 22 is deposited on the ruthenium layer by well known and conventional techniques such as vacuum coating, vapor deposition such as sputtering or ion deposition, and the like. The techniques and the ion spray device or equipment are described, 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 ", Soc. Vac Coat, Proc. 34 / a Arn. Techn.Conf., Philadelphia, USA, 1991, 48-61, and US Patent Nos. 4,162,954 and 4,591,418, all of which are incorporated herein by reference. in the ion spray deposition process the refractory metal such as the target or titanium or zirconium target, which is the cathode, and the substrate are placed in a vacuum chamber.The air in the chamber is evacuated to produce vacuum in the chamber An inert gas, such as argon, is introduced into the chamber.The gas particles are ionized and are accelerated to the target or target to dislodge the titanium or zirconium atoms. evicted target is then typically deposited as a coating film on the substrate. The layer 22 has a thickness which is at least effective for improving the adhesion of the layer 24 to the ruthenium layer 20. In general, this thickness is at least about 0.000000635 cm (0.00000025 inches), preferably at least about 0.00000127 cm (0.0000005 inches), and more preferably at least about 0.00000254 cm (0.000001 inches). The upper thickness range is not critical and generally depends on considerations such as cost. In general, however, layer 22 should not be thicker than about 0.000127 cm (0.00005 inches), preferably about 0.0000381 cm (0.000015 inches), and more preferably about 0.0000254 cm (0.000010 inches). In a preferred embodiment of the present invention the layer 22 is comprised of titanium or zirconium, preferably zirconium, and is deposited by ion spray plating. The layer 24 is comprised of a hafnium compound, a tantalum compound, a titanium compound or a zirconium compound, preferably a titanium compound or a zirconium compound, and more preferably a zirconium compound. The titanium compound is selected from titanium nitride, titanium carbide, and titanium carbonitride, with the titanium nitride being preferred. The zirconium compound is selected from zirconium nitride, zirconium carbonitride, and zirconium carbide, with the zirconium nitride which is preferred. The layer 24 provides resistance against abrasion and wear and the desired appearance or color, such as, for example, polished bronze. The layer 24 is deposited on the layer 22 by any of the well known and conventional plating or deposition processes such as vacuum coating, reactive ion sputtering, and the like. The preferred method is reactive ion spray plating. Reactive ion spray is generally similar to ion spray deposition except that a reactive gas that reacts with the target material dislodged is introduced into the chamber. Accordingly, in the case where the zirconium nitride is the top layer 24, the target or target is comprised of zirconium and the nitrogen gas is the reactive gas introduced into the chamber. By controlling the amount of nitrogen available to react with zirconium, the color of zirconium nitride can be made to be similar to that of bronze or brass of various shades or shades. The layer 24 has a thickness at least effective to provide resistance to abrasion. In general, this thickness is at least 0.000005 cm (0.000002 inches), preferably at least 0.00004 cm (0.000004 inches), and more preferably at least 0.0000152 cm (0.000006 inches). The range of the upper thickness in general is not critical and depends on considerations such as cost.

In general, a thickness of about 0.0000762 cm (0.00003 inches), preferably about 0.0000635 cm (0.000025 inches), and more preferably about 0.0000508 cm (0.000020 inches) in size, should not be exceeded. Zirconium nitride is the preferred coating material because it provides the appearance most similar to polished bronze. In order that the invention can be understood more easily, the following example is provided. The example is illustrative and does not limit the invention to it.

EXAMPLE 1 Ornamental door plates, made of bronze, are placed in a conventional soaking cleaning bath containing the well-known and standard soaps, detergents, deflocculants and the like, which is maintained at a pH of 8.9 - 9.2 and a temperature of 82.22. - 93.33 ° C (180 - 200 ° F) for 30 minutes. The ornamental brass shields are then placed for six minutes in a conventional ultrasonic alkaline cleaner bath. The ultrasonic cleaning bath has a pH of 8.9 - 9.2, is maintained at a temperature of about 71.11 - 82.22 (160 - 180 ° F), and contains well-known soaps and (160-180 ° F) and contains well-known soaps and conventional as well as detergents, deflocculants and the like. After the ultrasonic cleaning of the ornamental shields, they are rinsed and placed in a conventional alkaline electrolytic bath for approximately two minutes. The electrolippy bath contains an insoluble submerged steel anode, is maintained at a temperature of about 60-82.22 ° C (140-180 ° F), a pH of about 10.5-11.5, and contains standard and conventional detergents. The ornamental shields are then rinsed twice and placed in a conventional acid activator bath for about one minute. 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 ornamental shields are then rinsed twice and placed in a semi-gloss nickel plating bath for about 10 minutes. The semi-gloss nickel bath is a well known and conventional bath which has a pH of about 4.2 - 4.6, is maintained at a temperature of about 54.44 - 65.55 ° C (130 - 150 ° F), contains NiSO ,, NiCl, - , boric acid and brighteners. A layer of semi-gloss nickel of an average thickness of approximately 0.000255 inches (0.00025 inches) is deposited on the surface of the ornamental plate.

The ornamental plates containing the semi-gloss nickel layer are then rinsed twice and placed in a bright nickel plating bath for about 24 minutes. The briquetting nickel bath is generally a conventional bath which is maintained at a temperature of about 54.44 -65.55 ° C (130-150 ° F), a pH of about 4.0-4.8, contains NiSO ,, NiCl ", acid boric, and brighteners. A layer of bright nickel of an average thickness of approximately 0.001905 cm (0.00075 inches) is deposited on the semi-gloss nickel layer. The glossy and semi-glossy nickel plated ornamental plates are rinsed three times and placed in a conventional gold plating bath for approximately 30 seconds. The gold bath uses insoluble platinized titanium anodes, is maintained at a temperature of about 37.77-65.55 ° C (100-150 ° F), a pH of about 4.0-4.5, and contains about 4 grams per liter of gold. A layer of gold of an average thickness of approximately 0.0000076 cm (3 millionths of an inch) is deposited on the bright nickel layer. The ornamental plates are then rinsed twice. The gold plated ornamental plates are then placed in a convential ruthenium plating bath for about ten minutes. Ruthenium bath uses platinized titanium anodes, insoluble, is maintained at a temperature of about 65.55-76.66 ° C (150-170 ° F), a pH of about 1.0-2.0, and contains about 3 grams per liter of ruthenium. A layer of ruthenium of an average thickness of approximately 0.0000025 cm (10 millionths of an inch) is deposited on the palladium layer. The ornamental plates are then rinsed and completely dried. Ruthenium-plated ornamental plates are placed in an ion spray plating container. This container is a stainless steel vacuum vessel marketed by Leybol A.G. from Germany. The container is generally a cylindrical enclosure containing a vacuum chamber which 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 velocity of the argon towards the chamber. In addition, two sources of nitrogen gas are connected to the chamber by an adjustable valve to vary the flow velocity of nitrogen to the chamber. Two pairs of magnetron target or target mounts are mounted in a spaced relationship far into the chamber and connected to the negative outputs of the C.C. variable. The targets or targets constitute the cathodes and the wall of the chamber is a common anode for the target or target cathodes. The target or target material comprises zirconium. A carrier of the substrate which carries the substrates, i.e. the ornamental plates, is provided, for example, it can be suspended from the upper surface of the chamber, and is rotated by a variable speed motor to carry the substrates. between each pair of target mounts or magnetron target. The carrier is conductive and electrically connected to the negative output of a power supply of C.C. variable. Ruthenium-plated ornamental plates are mounted on the substrate carrier in the ion spray plating container. The vacuum chamber is evacuated at a pressure of approximately _3 5x10 millibars and is heated to approximately 400 ° C by means of a radiant electric resistance heater. The target or target material is spray cleaned to remove contaminants from its surface. Spray cleaning is carried out for approximately half a minute by applying sufficient energy to the cathodes to achieve a current flow of approximately 18 amps and introducing the argon gas at the rate of approximately 200 standard cubic centimeters -3 per minute . A pressure of approximately 3x10 millibar is maintained during the ion spray cleaning.

The ornamental plates are then cleaned by an acid attack process at low pressure. The process of acid attack at low pressure is carried out for approximately five minutes and involves applying a potential of C.C. negative which is increased over a period of time from one minute from about 1200 to about 1400 volts to the ornamental plates and by applying a power of C.C. to the cathodes to achieve a flow current of approximately 3.6 amps. The argon gas is introduced at a rate which is increased over a period of one minute from about 800 to about 1000 standard cubic centimeters per minute, and the pressure is maintained at approximately 1.1x10 millibar. Ornamental plates are rotated between the target or magnetron mountings at a rate of one revolution per minute. The ornamental plates are then subjected to a cleaning process by high pressure acid attack for approximately 15 minutes. In the high-pressure acid attack process, the argon gas is introduced into the vacuum chamber at a rate which increases over a period of 10 minutes from about 500 to 650 standard cubic centimeters per minute (i.e. start the flow rate is 500 sccm and after ten minutes the flow rate is 650 sccm and remains at 650 sccm for the rest of the acid attack process at high pressure), the pressure is maintained at almost 2x10 millibar, and a negative potential which is increased over a period of ten minutes from about 1400 to 2000 volts is applied to the plates or ornamental shields. Ornamental plates or shields are rotated between the target or magnetron mountings at approximately one revolution per minute. The pressure in the container is maintained at approximately 2x10 millibar. The ornamental plates or shields are then subjected to another cleaning process by acid attack at low pressure for about five minutes. During this cleaning process by acid attack at low pressure, a negative potential of approximately 1400 volts is applied to the plates or ornamental shields, the energy of C.C. is applied to the cathodes to achieve a current flow of approximately 2.6 amps, and the argon gas is introduced into the vacuum chamber at a rate which increases over a period of five minutes from approximately 800 sccm (standard cubic centimeters per minute) ) to approximately 1000 sccm. The pressure -2 is maintained at approximately 1.1x10 millibar and the shields or ornamental plates are rotated at approximately one rpm.

The target or target material is again cleaned by ion spray for about one minute by applying a sufficient amount of energy to the cathodes to achieve a flow of about 18 amps, introducing argon gas at a rate of about 150 sccm, and maintaining a pressure -3 of approximately 3x10 millibar. During the cleaning process, protections or defenses are interposed between the ornamental plates or shields and the target or magnetron mounts to prevent deposition of target material on the shields or ornamental plates. The protections or fenders are removed and a layer of zirconium having an average thickness of approximately 0.0000076 cm (0.000003 inches) is deposited on the ruthenium layer of the ornamental plates or shields for a period of four minutes. This ion spray deposition process comprises applying energy from C.C. to the cathodes to achieve a flow current of approximately 18 amps, introduce the argon gas into the vessel at about 450 sccm, maintain the pressure in the vessel at about 6x10 millibar, and rotate the shields or ornamental plates at about 0.7 revolutions per minute. After the zirconium layer is deposited a layer of zirconium nitride having an average thickness of about 0.0000355 cm (0.000014 inches) is deposited on the zirconium layer by reactive ion spray for a period of 14 minutes. A negative potency of approximately 200 volts of C.C. it is applied to ornamental plates or shields while an energy of C.C. It is applied to the cathodes to achieve a flow of about 18 amps. The argon gas is introduced at a flow rate of approximately 500 sccm. Nitrogen gas is introduced into the vessel from two sources. A source introduces nitrogen at a generally steady flow rate of about 40 sccm. The other source is variable. The variable source is regulated to maintain a partial ionic current of 6.3x10 amperes, with the variable flow of nitrogen being increased or reduced when necessary to maintain the partial ionic current at this predetermined value. The pressure in the container is maintained in approximately 7.5x10 millibar. The ornamental plates or shields coated with zirconium nitride are then subjected to downward cooling at low pressure, where the heating is discontinued, the pressure is increased from approximately 1.1x10 -2 millibar to approximately 2x10-] millibar, and the Argon gas is introduced at a rate of 950 sccm Although the present invention has been described in conjunction with the preferred embodiments, it is to be understood that modifications and variations can be used as a resource without departing from the spirit and scope of the invention, as will be readily understood by those skilled in the art, such modifications and variations are considered to be within the scope and scope of the invention and the appended claims.

It is noted that in relation to this date, the best method known by the applicant to carry out the aforementioned invention, is the conventional one for, the manufacture of the objects to which it refers.

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

Claims (21)

R E I V I N D I C A C I O N S

1. An article comprising a metal substrate having on it at least a portion of its surface a multilayer coating that simulates bronze or brass, characterized in that it comprises: a layer comprised of semi-gloss nickel on at least a portion of the surface of the substrate; a layer comprised of bright nickel on at least a portion of the layer comprised of semi-glossy nickel; a layer comprised of gold over at least a portion of the layer comprised of bright nickel; a layer comprised of ruthenium over at least a portion of the layer comprised of gold; a layer comprised of zirconium or titanium on at least a portion of the layer comprised of ruthenium; and a layer comprised of a zirconium compound or a titanium compound on at least a portion of the layer comprised of zirconium or titanium.

2. The article according to claim 1, characterized in that the layer comprised of zirconium or titanium is comprised of zirconium.

3. The article according to claim 2, characterized in that the layer comprised of a zirconium compound or a titanium compound is comprised of a zirconium compound.

4. The article according to claim 3, characterized in that the zirconium compound is comprised of zirconium nitride.

5. The article according to claim 1, characterized in that the metal substrate is comprised of brass or brass.

6. An article comprising a substrate having on at least a portion of its surface a coating having a bronze or brass color and characterized in that it comprises a layer comprised of semi-glossy nickel; a layer comprised of bright nickel; a layer comprised of gold; a layer comprised of ruthenium; a layer comprised of zirconium; and a layer comprised of a zirconium compound.

7. The article according to claim 6, characterized in that the substrate is comprised of brass or brass.

8. The article according to claim 7, characterized in that the layer comprised of the zirconium compound is comprised of zirconium nitride.

9. The article according to claim 6, characterized in that the layer comprised of the zirconium compound is comprised of the zirconium nitride.

10. An article comprising a metallic substrate, characterized in that it has placed on at least a portion of its surface a multilayer coating comprising: a layer comprised of semi-glossy nickel; a layer comprised of bright nickel; a layer comprised of gold; a layer comprised of ruthenium; a layer comprised of zirconium or titanium; and a layer comprised of a zirconium compound or a titanium compound.

11. The article according to claim 10, characterized in that the layer comprised of zirconium or titanium is comprised of zirconium.

12. The article according to claim 11, characterized in that the layer comprised of the zirconium compound or the titanium compound is comprised of a zirconium compound.

13. The article according to claim 12, characterized in that the zirconium compound is comprised of zirconium nitride.

14. The article according to claim 13, characterized in that the metallic substrate is comprised of brass or brass.

15. The article according to claim 11, characterized in that the metal substrate is comprised of brass or brass.

16. An article comprising a substrate, characterized in that the substrate has on at least a portion of its surface a coating comprising a first layer comprised of semi-glossy nickel; a second layer on at least a portion of the first layer, comprised of bright nickel; a third layer on at least a portion of the second layer comprised of gold; a fourth layer on at least a portion of the third layer comprised of ruthenium; a fifth layer on at least a portion of the fourth layer, comprised of zirconium or titanium; and a sixth layer on at least a portion of the fifth layer comprised of a zirconium compound or a titanium compound.

17. The article according to claim 16, characterized in that the substrate is comprised of brass or brass.

18. The article according to claim 16, characterized in that the fifth layer is comprised of zirconium.

19. The article according to claim 18, characterized in that the sixth layer is comprised of the zirconium compound.

20. The article according to claim 19, characterized in that the sixth layer is comprised of a zirconium nitride.

21. The article according to claim 20, characterized in that the substrate is comprised of brass or brass.