Method for manufacturing coated plastic or metal substrates and metallic-looking coatings

Abstract

A plastic or metallic substrate (100) comprising at least one first layer (10) made of a metallic substance or metallic component and at least one second layer (11) made of a metallic substance or metallic compound, wherein the first layer (10) is deposited on the substrate (100) by cathode sputtering and is made of a substance having an elastic modulus of 150 Gpa or less, preferably 125 Gpa or less, and the second layer (11) is deposited on the first layer (10) by cathode sputtering and is made of a substance having a Vickers hardness of 600 or more.

Description

Technical Field

[0001] The subject of the present invention is related to a substrate made of plastic or painted plastic or painted metal, and a related method for manufacturing a coating having a chromated appearance.

[0002] In particular, the coated substrate (and method) is obtained by the deposition of a multilayer metal-based coating applied to a part by sputtering technology. In fact, the coating (and related method) is used, for example, on plastic parts and products such as ABS, PCABS, and others, or on painted plastic or painted metal, to impart a metallic appearance (similar to chrome plating).

Background Art

[0003] Metal coatings on plastic articles obtained by galvanic chrome plating processes are generally used in many manufacturing industries such as the automotive industry and the household appliance industry. Due to this extensive use and recent regulations, there is a desire to find alternatives that have similar functionality, even if they are not necessarily excellent.

Technical Field

[0004] Metal coatings on plastic surfaces can also be achieved by other techniques. For example, one of the most well-known techniques is deposition on a substrate by cathodic sputtering technology.

[0005] Such cathode spattering is used in known specifications in mechanical devices including a vacuum chamber (in which the substrate to be coated is placed). Coating of such a substrate occurs by the deposition of atoms or ions ejected by a sacrificial solid that is subjected to high-energy particle collisions on its surface. In particular, the ejection of atoms or ions by the sacrificial solid is due to multiple high-energy particles, such as plasma-state gas ions (which collide with the sacrificial solid, hence the sacrificial solid is also referred to as the "target"). In fact, the target is subjected to erosion. Specifically, during the erosion of the target, coating material in the form of atoms, ions, or molecular parts detach from the target, disperse into the surrounding area, and eventually adhere to the deposition substrate. The erosion of the target will occur thanks to the use of a highly ionized gas in a "plasma" state (the gas is inserted between the target and the deposition substrate, preferably excited to provide high-energy particles, which collide with the target and cause the aforementioned erosion). Obviously, the metallic material deposited on the substrate is a pure metal, such as chromium or silver or its reactive compounds. For example, in the case of using chromium as the target material, the material deposited on the substrate is substantially pure chromium (chromium nitride (CrN) if the strongly ionized gas used is nitrogen, chromium carbide (CrC) if the strongly ionized gas used is acetylene or methane, and chromium oxide (CrO) if the strongly ionized gas used is oxygen), or a combination of chromium and one of its functional components (depending on the gas selected).

[0006] Material deposition apparatuses are well known and have a potential difference (e.g., several kV) between the target object and the deposition substrate. Typically, the target object is the cathode (negative electrode), while the substrate or vacuum chamber is the anode (positive electrode).

[0007] When an inert gas, such as argon, is introduced between the target and the deposition substrate under appropriate pressure conditions (e.g., several mTor), free electrons in the gas are accelerated away from the negative charge of the cathode, hitting atoms in the inert gas and ionizing them. In this way, a chain reaction is triggered, resulting in a powerful ionized gas, or "plasma." The ionized atoms of the inert gas, in this case, are positively charged atoms and are therefore accelerated by electrical attraction toward the cathode (represented in this case by the target). The ionized atoms collide with the surface of the target, causing the detachment of coating material (atoms or ions) from the target. The detached coating material disperses in the opposite direction to the direction occupied by the target, resulting in adhesion to the deposition substrate.

[0008] Mechanical apparatus for material deposition is known and further comprises multiple magnets capable of generating a magnetic field (to form a so-called "magnetron"). Such magnets are typically positioned below the target body or behind it, on the opposite side from where the substrate to be coated is placed. As a result, the resulting magnetic field interacts with ionized atoms in the space between the target body and the deposition substrate, thereby increasing the path to the target body and thus increasing the likelihood of particle collisions. This results in increased process yield.

[0009] Although cathode spattering techniques have recently become widely used as an alternative to galvanic processes, the resulting coatings, while aesthetically pleasing and successful in preventing moisture from reaching the substrate surface, have generally proven ineffective in the case of plastic or painted metal substrates because they fail to prevent cracking in the coating caused by mechanical and / or thermal expansion that plastic or painted metal substrates undergo during normal use. The presence of deep cracks reaching the underlying material firstly imparts an unaesthetic appearance to the plastic component, and secondly, it impairs the integrity and functionality of the coating, leading to coating detachment and, consequently, exposure of the coated material surface.

[0010] Japanese Patent Publication No. 2008-191528 discloses a reflective coating. The coating, deposited by sputtering, consists of a first layer of silver or an alloy thereof with a thickness of 50 to 500 nm and a second protective layer of SiAlON with a thickness of 0.5 to 10 nm. Japanese Patent Publication No. 2008-191528 makes no mention of the elastic modulus value. The coating is suitable for a wide variety of articles, including optical reflectors, electrodes, reflective mirrors, electronic devices, reflectors for lighting fixtures, general lighting fixtures, backlighting, LED lighting fixtures, displays, and optical discs.

[0011] D. Evans et al., Surface and Coatings Technology, Vol. 206(2), pp. 312-317, 2011, disclose a wear-resistant coating. In the examples section, a polymer material support is immersed in a hard resin to a thickness of 4.6 microns, and then coated with a 140 nm thick SiO2 layer by sputtering. Subsequently, a 40-50 nm thick CrNx layer is further coated by sputtering. Although SiO2 is not a metallic material, it is applied to provide wear resistance.

[0012] Japanese Patent Publication No. 2015-104924 discloses a transparent coating for electronic devices. The coating comprises a first layer (underlayer) made of chromium, a second layer (transition layer) made of chromium carbide, and a third layer (transparent layer) made of silicon. The thickness of the underlayer is in the range of 100 to 300 nm, and the thickness of the transition layer is in the range of 200 to 400 nm. The layers are deposited by sputtering. In this case as well, silicon is not a metal, and the coating is transparent.

[0013] To date, apart from coatings obtained by galvanic processes, there are no known coatings for plastic or metal materials that enable the achievement of optimal results in both aesthetics and resistance to surface cracking. [Overview of the project] [Problems that the invention aims to solve]

[0014] The object of the present invention is to produce a technical coating by cathode sputtering that is applicable to plastic or painted plastic supports or painted metal supports and is aesthetically similar to those obtained by existing galvanic processes.

[0015] Another object of the present invention is to produce a coating that prevents surface cracking.

[0016] Finally, the objective of the present invention is to develop a method for implementing the proposed solution. [Means for solving the problem]

[0017] The above objectives are achieved by coatings for plastic or metal substrates as defined in the claims.

[0018] Thus, a first aspect of the present invention relates to a substrate made of a plastic or metal material with a coating, wherein the coating comprises a first layer (10) made of at least one metal material or metal compound, a second layer (11) made of at least one metal compound, and a third layer (12) made of at least one metal material or metal compound, where, The first layer is deposited on the substrate by sputtering, and the first layer is made of a material having an elastic modulus of 150 GPa or less. The second layer is deposited on the first layer by cathode spattering, and the second layer is made of a material having a hardness of 5.884 GPa (600 Vickers) or more, and

[0019] The third layer is deposited on the second layer of the metallic material or metallic compound by cathode spattering and has a reflectance of 55-70% in the visible spectrum.

[0020] Preferably, the elastic modulus of 150 GPa or less is in the range of 4.5 to 150 GPa, preferably 4.5 to 125 GPa.

[0021] Preferably, a hardness of 5.884 GPa (600 Vickers) or higher is in the range of 5.884 GPa (600 Vickers) to 60 GPa (6,000 Vickers).

[0022] Here, "metallic material" means a pure metal or a mixture of metallic materials (as a dispersion or alloy).

[0023] Here, “metallic compound” means a pure metallic material or a mixture of metallic materials (as a dispersion or alloy) and one or more nonmetallic elements (as a dispersion or alloy), and the “metallic compound” is produced by the co-deposition of different materials (metallic and nonmetallic materials) or by reaction with a reactive gas (more broadly described below).

[0024] In fact, due to its elasticity, the first layer deposited on the substrate can compensate for the different thermal expansion rates and mechanical elongations of the materials involved in the coating process. Thus, the generation of cracks and delamination within the entire coating can be prevented. Considering that the general thermal expansion rate of plastics, such as PCABS plastics, is about 80×10 -6mm / K (a measure that is approximately higher than the thermal expansion rate of chromium), the first "shock-absorbing" layer can completely eliminate cracks visible to the naked eye. In particular, after stretching the size of the plastic substrate by 1%, their density measured under a microscope can be reduced to a value of 0.01 crack number / line mm.

[0025] It is clear that the term "plastic" includes various polymers recognized by those skilled in the art as "plastics", such as thermoplastic polymers, thermosetting polymers, elastomers, resins, rubbers, etc.

[0026] Furthermore, due to its physical / chemical properties, such a first layer must enable good adhesion to the surface to be coated (about 50 GPa or more). This adhesion property is also strongly influenced by the elastic performance of the material constituting the first layer.

[0027] Ultimately, the first layer functions as a shock-absorbing layer.

[0028] Preferably, the first layer has a thickness of 50 - 400 nm.

[0029] Since the second layer is made using a material with a hardness of 600 Vickers or more, it imparts wear resistance to the entire package.

[0030] Preferably, the second layer is not made solely of a metal compound.

[0031] Preferably, the second layer is not made of SiAlON.

[0032] The second layer preferably has a thickness of 15 nm or more, preferably 30 nm or more, and more preferably, the thickness is in the range of 50 - 400 nm.

[0033] Furthermore, the coating may preferably include a third layer deposited on the second layer by cathode spattering; the third layer is made of a metallic material or metallic compound and has a reflectance of 55-70% in the visible spectrum.

[0034] Preferably, the third layer contains at least chromium.

[0035] In reality, the third layer is the "aesthetic" layer. The third layer imparts high reflective properties to the entire coating. This layer is generally chromium-based because it partially gives the coating a common chromized appearance similar to that produced by galvanic coatings.

[0036] In a specific example, the third layer may also consist of additional agents selected from, for example, dopants, dyes, antimicrobial agents, and mixtures thereof.

[0037] Furthermore, the coating may also include an additional paint layer placed between the substrate and the first layer; the paint layer consists of a paint selected from thermal paint and UV paint. Such a paint layer is essential in the case of plastic substrates.

[0038] According to the proposed solution, the first and / or second layers are made of a substantially pure metallic material and / or a reactive compound thereof, where the pure metallic material is selected from chromium, silver, copper, and indium, and the reactive compound is obtained by a gas selected from argon, oxygen, nitrogen, methane, and mixtures thereof, for example, argon and methane, argon and acetylene, nitrogen and methane.

[0039] According to the special solution, the first layer and / or the second layer and / or the third layer are made of chromium and / or chromium nitride and / or chromium carbide and / or chromium oxide and / or chromium carbonitride, however, The first layer is not composed solely of chromium; The second layer is not composed of metal compounds; Preferably, the third layer contains at least chromium.

[0040] In a particular embodiment, the first layer preferably comprises chromium carbide or chromium carbonitride.

[0041] In a specific example, the second layer preferably contains chromium nitride.

[0042] In a specific example, the first layer may be the same metallic material or metallic compound as long as the first layer has an elastic modulus of 150 GPa or less, preferably 125 GPa or less, and the second layer has a hardness of 600 Vickers or more.

[0043] However, while both the first and second layers can be obtained by deposition of multiple metal layers, it must be made clear that the metal layers must, as a whole, impart to the first and second layers the elastic and hard mechanical properties required by the present invention in order to achieve the desired technical effects.

[0044] For example, the first layer may consist of a first portion of a chromium layer for good adhesion to the substrate, and then a second portion of a chromium carbide layer on the first portion of the layer, and because the amount of chromium carbide is greater in this first layer, overall better elastic properties (thus, greater elasticity) are imparted than those of a chromium layer alone (i.e., the elastic modulus of the chromium layer is lower).

[0045] The third layer is preferably made of chromium, but other materials or reactive compounds can also be used as long as their reflectance in the visible spectrum is 55-70%.

[0046] The object of the present invention is also achieved by a method for producing a coating on a substrate made of a plastic or metal material, according to one or more claims of the claims, using an apparatus for deposition by cathode spattering, the apparatus comprising at least one vacuum chamber, an evaporator for a target body and at least one support for the substrate (the evaporator and support are located within the vacuum chamber), and the method is, a) A step of placing a substrate made of metal or plastic material onto a support; b) A step of depositing a first layer of metal or metal compound on a substrate by cathode sputtering; c) A step of depositing a second layer of metal compound by cathode spattering on the first metal layer. The first metal layer is made of a metal material or metal compound having an elastic modulus of 150 GPa or less, preferably 125 GPa or less, and the second layer is made of a metal compound having a hardness of 600 Vickers or more.

[0047] The exemplified ranges of elastic modulus and hardness also apply to the method of the present invention.

[0048] Furthermore, prior to step a), the process includes coating the substrate with a paint selected from thermal paint and UV paint.

[0049] Furthermore, the method also includes step d) depositing a third layer of metal or a metallic compound onto the second layer by cathode sputtering, wherein the third layer is made of a metallic material or metallic compound having a visible spectral reflectance of 55-70%. The third layer preferably contains chromium.

[0050] Step b) or step c) or step d) is carried out by using an ionized and properly excited gas selected from argon, oxygen, nitrogen, methane, acetylene, and mixtures thereof as a carrier gas.

[0051] Finally, the target material is selected from chromium, silver, copper, and indium.

[0052] In fact, by using one or more ionized gases and one or more target bodies, a first, second, and third layer can be obtained made of a metallic material or metallic compound selected from chromium, silver, copper, and indium and / or a reactive compound thereof (obtained from oxygen, nitrogen, methane, acetylene, and mixtures thereof). [Brief explanation of the drawing]

[0053] [Figure 1] This is a diagram showing a cross-section of a cathode spattering device. [Figure 2] This figure shows a cross-section of a substrate that has been coated using the apparatus shown in Figure 1. [Figure 3] This figure shows images under a 50X microscope of three T85XF plates (a), (b), and (c) (each with a different coating) with UV-type paint after treatment in an oven at 70 / 80°C for 5 hours (not according to the present invention). [Figure 4] This figure shows image images under a 50X microscope of three T85XF plates (d), (e), and (f) (each with a different coating) filled with UV-type paint and filled with fiberglass after treatment in an oven at 70 / 80°C for 5 hours (not according to the present invention). [Figure 5] This figure shows additional images under a 50X microscope of three T85XF plates (g), (h), and (i) (each with a different coating) with UV-type paint after treatment in an oven at 70 / 80°C for 5 hours (not according to the present invention). [Figure 6] This figure shows additional images under a 50X microscope of three T85XF plates (a'), (b'), and (c') (each with a different coating) with UV-type paint after treatment in an oven at 70 / 80°C for 5 hours (not according to the present invention). [Figure 7]This figure shows images under a 50X microscope of three T85XF plates (d'), (e'), and (f') (each with a different coating) filled with UV-type paint and fiberglass after treatment in an oven at 70 / 80°C for 5 hours (not according to the present invention). [Modes for carrying out the invention]

[0054] Various specific examples and modifications of the present invention will be described with reference to the drawings above. In particular, the coating according to the present invention is indicated by reference numeral 1.

[0055] Figure 1 shows an apparatus 200 for obtaining a coating 1 on a plastic or metal substrate 100 according to the present invention.

[0056] Such an apparatus 200 comprises, in a highly systematic manner, a vacuum chamber 201 (in which the substrate 100 to be coated is placed). The coating 1 on the substrate is produced by the deposition of atoms or ions on its surface by a sacrificial solid or target 202 subjected to high-energy particle collisions. The sacrificial solid 202 is placed in an evaporation apparatus 204 arranged to supply a vapor phase evaporation material for the solid sacrificial solid. In particular, the emission of atoms or ions by the sacrificial solid 202 is produced by multiple high-energy particles, such as plasma-state gas ions (which collide with the sacrificial solid 202). In particular, the sacrificial solid 202 undergoes an erosion process. In particular, during the erosion of the sacrificial solid 202, parts of the sacrificial solid 202 are pulled away from the sacrificial solid, dispersed into the surrounding area, and finally adhere to the deposition substrate 100 held on a substrate support 203. The erosion of the target body 202 may be carried out by using a highly ionized gas in a "plasma" state that is appropriately excited to provide high-energy particles to be inserted between the sacrificial body 202 and the substrate 100 and to collide with the sacrificial body 202 (causing the erosion). As is obvious, the metallic material deposited on the substrate 100 may be a pure metal, such as chromium or silver, or a functional component thereof. For example, in the case of using chromium as the sacrificial body 202 or target, the material deposited on the substrate may be, depending on the gas used, substantially pure chromium or chromium nitride (CrN) if the highly ionized gas used is nitrogen; chromium carbide (CrC) if the highly ionized gas used is acetylene or methane; chromium oxide (CrO) if the highly ionized gas used is oxygen; chromium carbonitride (CrCN) if the highly ionized gas used is a mixture of methane and nitrogen or a combination of chromium and its functional component (depending on the selected gas).

[0057] It should be noted that the crude formulations shown above merely represent the elements that make up the layers, and include all possible compounds / compounds that can be formed from the elements explicitly stated in these formulations.

[0058] When the first layer comprises a first portion of substantially pure chromium, the first layer must include additional portions that are not composed solely of pure chromium in order to conform to the elastic modulus value defined herein, as detailed below.

[0059] Next, the growth of coating 1 depends on many factors, including the pressure in the vacuum chamber, the flow rate of the ionizing gas, the strength and shape of the static magnetic field generated in the target body 202 within the vacuum chamber, and many other factors, in addition to the target material 202 and the ionizing gas. Therefore, although composed of the same material, coating layers with different mechanical properties can be obtained because they depend on the concentration of the enclosed gas within the same layer deposited on the substrate 100.

[0060] In the specific example described herein, the substrate 100 is made of plastic, but in other specific examples, such a covered substrate 100 may be made of metal.

[0061] Coating 1 comprises a first layer 10 of a metallic material or metallic compound and a second layer 11 of a metal or metallic compound. The first layer is deposited on the substrate 100 by cathode sputtering and has an elastic modulus (or Young's modulus) of 125 GPa or less. In either case, a first layer having an elastic modulus of 150 GPa or less is also within the scope of protection of the present invention.

[0062] The second layer 11 is deposited on the first layer 10 by cathode spattering and is made of a metallic compound having a hardness of 600 Vickers or more.

[0063] In the specific example described herein, the first layer has a thickness of 150 nm, but in other specific examples, such a first layer 10 can have a thickness of 50 to 400 nm, but this does not fall outside the scope of protection of the present invention.

[0064] The second layer 11 has a thickness of 200 nm, but in other specific examples, such a first layer 10 can have a thickness of 50 to 400 nm, without exceeding the scope of protection of the present invention.

[0065] Furthermore, coating 1 includes a third metal layer deposited on the second layer by cathode spattering. Such a third metal layer 12 is made of a metallic material or a metallic compound, has a visible spectral reflectance of 55-70%, and contains chromium.

[0066] In particular, with respect to each deposited layer 10, 11, and 12, the metallic material or metallic compound has mechanical and / or physical properties that enable the coating 1 itself to prevent crack formation.

[0067] In fact, the first layer functions as a cushion or shock-absorbing layer between the substrate 100 and the second layer 11. Due to the elastic properties of the constituent material, the first layer 10 can compensate for the difference in thermal expansion coefficient and mechanical elongation coefficient of the materials involved in the process, thereby preventing the occurrence of cracks and delamination within the entire coating.

[0068] On the other hand, the second layer 11 ("hardened" layer) imparts hardness to the coating, thereby ensuring high wear resistance.

[0069] Finally, the third layer 12 is an aesthetic layer, i.e., it is used to impart to the substrate being coated a finish desired by the end user (who would likely require a finish similar to that obtained by known zinc plating processes).

[0070] In the specific example described herein, coating 1 comprises an additional printed layer 13 positioned between the substrate 100 and the first layer 10. Such a printed layer 13 is made of a paint selected from thermal paint and UV paint. In fact, the substrate 100 is coated with such a paint layer 13 before it is covered by cathode spattering in the apparatus 200.

[0071] Preferred chromium metal compounds are selected from chromium nitride (CrN), chromium carbide (CrC), chromium oxide (CrO), chromium carbonitride (CrCN), or combinations of chromium and its metal compounds, such as chromium nitride (CrN), chromium carbide (CrC), chromium oxide (CrO), and chromium carbonitride (CrCN).

[0072] In particular, in the specific example described here, the first layer 10 is made of chromium carbide with a high carbon content, and therefore its elastic modulus is 125 GPa or less. Specifically, the chromium carbide of the first layer 10 is manufactured so that its elastic modulus is 90 GPa.

[0073] In practice, it has been experimentally observed that the elastic modulus of chromium carbide changes significantly depending on the available carbon content in the ionization gas mixture used. When the carbon content is high and the target material used is chromium, almost all of the material eroded from the sacrificial material combines with carbon to form chromium carbide, while the remaining portion where no more carbon is available is deposited on the substrate as chromium. Under carbon-saturated conditions, all of the chromium combines with it, resulting in the entire first layer being composed of chromium carbide.

[0074] However, in some cases, some of the available carbon remains trapped in the material constituting the first layer 10, contributing to the change in the elasticity of the first layer 10. In this case, the first layer 10 may contain chromium carbide (CrC), chromium and carbon, or chromium carbide (CrC) and carbon. The crude formulations of chromium carbide (CrC) described above are purely illustrative and include all possible compounds / compounds formed with the elements specified in the crude formulations. In particular, in the case where the apparatus 200 operates under an acetylene / methane atmosphere, the coated compound may have not only chromium carbide (CrC) and chromium, but also small amounts of -C:H and / or -C, i.e., amorphous carbon molecules in the form of graphite or diamond.

[0075] Other materials particularly suitable for the first layer include chromium carbonitride, as will be evident from the experimental examples below.

[0076] Furthermore, the inventors have found that the first layer 10 may comprise a first portion of a chromium layer for greater adhesion to the substrate and a second portion of a chromium carbonitride or chromium carbide layer on top of the first portion of the layer, and that the greater amount of chromium carbonitride or chromium carbide imparts better elastic properties to the entire first layer than chromium alone (i.e., the elastic modulus of chromium is low) (thus resulting in greater elasticity). The first chromium portion is preferably deposited on a painted substrate 100, while the second chromium carbonitride or chromium carbide portion is deposited on top of the first chromium portion.

[0077] 1. In a specific example, the first layer 10 comprises chromium carbonitride and / or chromium carbide.

[0078] 1. In a specific example, the first layer 10 is made of chromium, chromium carbonitride and / or chromium carbide.

[0079] In either case, whatever the material constituting the first layer may be, the first chromium portion may always be deposited to ensure good adhesion of the first layer to the substrate 100. The second portion of the first layer may be formed of a material such that the overall elastic modulus of the first layer is 150 GPa or less, preferably 125 GPa or less.

[0080] Furthermore, the second layer 12 preferably contains chromium nitride.

[0081] In a specific example, the first layer 10 and the second layer 11 are formed primarily of chromium carbide (or chromium nitride or other reactive chromium compounds), but the mechanical properties of the formed layers can be altered depending on the carbon concentration of the ionizing gas used in the apparatus 200, resulting in materials with greater elasticity or greater hardness. For example, if the concentration of carbon ions in the plasma state is high (derived from strongly ionized methane or acetylene), the chromium extracted from the sacrificial material combines with carbon to form chromium carbide, and some of the chromium from the sacrificial material is deposited as simple chromium. This final compound (which constitutes the first layer) will have altered mechanical properties depending on the desired concentrations of chromium and chromium carbide, resulting in materials that are more elastic or harder. Variations in the composition of the first layer can be obtained by simply using the apparatus 200.

[0082] The specific examples described above can be extended to cases where other reactive compounds of chromium are used, or where other pure materials (e.g., copper, silver, or indium) and their respective reactive compounds are used as sacrificial materials. In the case of copper and silver, since the elastic modulus of these materials is 150 GPa or less, the first layer 10 is formed entirely from these materials. In this case, the use of a first portion of the chromium layer deposited on the substrate and a second portion of the copper, indium, or silver layer can be provided.

[0083] The third layer 13 is preferably made of chromium.

[0084] The coating 1 on the substrate 100 is fabricated by a cathode sputtering deposition apparatus 200 of the type described above and shown in Figure 1, the apparatus comprising a vacuum chamber 210, one or more evaporators 204 for a target (or sacrificial) body 202, and a support 203 for the substrate 100, the evaporators 204 and the support 203 being placed inside the vacuum chamber 201.

[0085] As will be detailed in the experimental section below, the method of the present invention using apparatus 200, unlike the conventional method, makes it possible to achieve a homogeneous, crack-free coating even after oven treatment. The method for producing a coating using such a device 200 is as follows: a) A step of preparing the substrate 100 on a support 203 placed inside the vacuum chamber 201 of the apparatus 200; b) A step of depositing the first layer 10 defined herein onto the substrate 100 by cathode spattering; and c) A step of depositing the second layer 11 defined herein onto the first layer 10 by cathode spattering. The material comprises the following: the first layer 10 is made of a material having an elastic modulus of 150 GPa or less, preferably 125 GPa or less, and the second layer is made of a material having a hardness of 600 Vickers or more.

[0086] Furthermore, a step of coating the substrate 100 with a paint selected from thermal paint and UV paint may be included before step a). In the specific example described herein, the paint is of the thermal type. However, in other specific examples, the substrate 100 may also be made of painted metal.

[0087] The method also includes step d) depositing a third metal layer on the second layer 11 by cathode sputtering. Such a third layer is made of a metallic material or metallic compound having a visible spectral reflectance of 55-70% and containing at least chromium. In the specific example described herein, such a metallic material or metallic compound has a visible spectral reflectance of 60%.

[0088] Furthermore, step b), c), or d) may optionally be carried out in the presence of argon, using an ionized and appropriately excited gas selected from argon, oxygen, methane, or acetylene as a carrier gas.

[0089] Finally, target material 202 is selected from chromium, silver, copper, and indium.

[0090] In this way, depending on the selected gas, the first layer 10 and / or the second layer 11 and / or the third layer 12 are made from metallic materials selected from chromium, silver, copper and indium and / or their reactive compounds, as defined herein.

[0091] In particular, if the target material is chromium, the first layer 10 and / or the second layer and / or the third layer 12 are made of a material selected from chromium, chromium nitride (CrN), chromium carbide (CrC), chromium oxide (CrO), and combinations thereof, provided that the above-defined conditions are met.

[0092] The first layer 10 is preferably made of chromium carbonitride or chromium carbide.

[0093] The second layer 11 is preferably made of chromium nitride.

[0094] Finally, the third layer 12 is preferably made of chromium.

[0095] The present invention will be described in detail in the section on examples below, but these are merely illustrative and do not limit the present invention.

[0096] Examples section [Example 1] T85XF plates (or substrates) (with or without fiberglass) were coated by deposition of single-layer or multi-layer metallic coatings using the "sputtering" technique. Such plates or substrates were pre-painted with UV-type paint and left to dry for approximately 60 seconds. Figures 3-7 show images of samples coated according to the present invention and comparative samples under a 50X microscope after treatment at 70 / 80°C for 5 hours.

[0097] [Comparative Example] Figure 3 shows the results of treating T85XF plastic plates coated with (a) Cr-CrN-Cr (total thickness 600 nm), (b) an AgCr mix containing 10% Ag (total thickness 850 nm), and (c) Cr-CrN-Cr (total thickness 830 nm) without following the present invention. At the end of the process, all samples had cracks that were visible even to the naked eye. A multilayer coating (having one or more layers) must be recognized, for example, in the case of the Cr-CrN-Cr coating described above, as a coating having chromium as the first layer, chromium nitride as the second layer, and chromium as the third layer, from left to right. Figure 4 shows the results of treating T85XF plates (including fiberglass) coated with (d) Cr-CrN-Cr (coating with a total thickness of 600 nm), (e) Cr-CrN-Cr (coating with a total thickness of 830 nm), and (f) AgCr containing 10% Ag (coating with a total thickness of 850 nm), without following the present invention. After oven treatment, all samples had cracks that were visible even to the naked eye. Figure 5 shows the results of treating T85XF plates coated with (g) a CrAg single layer containing 5% Ag (a coating with a total thickness of 420 nm), (h) a CrAg single layer containing 10% Ag (a coating with a thickness of 440 nm), and (i) a test CrAg single layer containing 15% Ag (a coating with a total thickness of 420 nm), without following the present invention. All samples had cracks that were visible even to the naked eye. In fact, in the above embodiment, the first layer always has an elastic modulus of 150 GPa or more, as described in the claims.

[0098] [Examples of the present invention] Figure 6 shows the results of treating T85XF plates coated with (a') Cu-CrN-Cr (a coating with a thickness of 200 nm for Cu and a thickness of 600 nm for the remaining two layers), (b') Ag-CrN-Cr (a coating with a thickness of 200 nm for Ag and a thickness of 680 nm for the remaining two layers), and (c') CrCN-CrN-Cr (a coating with a total thickness of 830 nm) according to the present invention. Such a plate has a first layer comprising a very thin first portion of a chromium layer and a second portion of a chromium nitride layer. The thickness of this first layer is several tens of nanometers. After oven treatment, none of the samples had any cracks visible to the naked eye. Samples (a') and (b') showed cracks that were only visible under a microscope. Sample (c') had no cracks visible under a microscope. Figure 7 shows the results of treating a T85XF plate (including fiberglass) coated with (d') Cu-CrN-Cr (a coating with a thickness of 200 nm for the first layer of Cu and a thickness of 600 nm for the remaining two layers) according to the present invention, (e') Ag-CrN-Cr (a coating with a thickness of 200 nm for the first layer of Ag and a thickness of 680 nm for the remaining two layers), and (f') CrCN-CrN-Cr (01) (a coating with a total thickness of 830 nm). Before and after oven treatment, none of the samples showed any cracks visible to the naked eye. Samples (d') and (e') showed cracks that were only visible under a microscope. Sample (c') did not have any cracks. Ta.

[0099] conclusion A comparison of the results obtained for samples treated according to the method of the present invention and for comparative samples clearly shows that the method of the present invention provides excellent results in preventing the occurrence of cracks in the coating. In some cases, the cracks are visible only under a microscope, but this result is acceptable because, in an important aspect, these cracks are not visible to the naked eye.

Claims

1. A substrate (100) made of plastic or metal material having a coating (1), wherein the coating (1) comprises at least one first layer (10) made of a metal material or metal compound, at least one second layer (11) made of a metal compound, and at least one third layer (12) made of a metal material or metal compound, The first layer (10) is deposited on the substrate (100) by cathode sputtering and is made of a material having an elastic modulus of 150 GPa or less; The second layer (11) is deposited on the first layer (10) by cathode sputtering and is made of a material having a hardness of 5.884 GPa (600 Vickers) or more; and The third layer (12) is deposited on the second layer (11) by cathode sputtering of a metallic material or metallic compound having 55-70% visible spectral reflectance, in a substrate.

2. The substrate according to claim 1, wherein the first layer (10) has a thickness of 50 to 400 nm.

3. The substrate according to claim 1, wherein the first layer (10) has an elastic modulus of 125 GPa or less.

4. The substrate according to claim 1, further comprising a printed layer (13) disposed between the substrate and the first layer, wherein the printed layer is made of a paint selected from thermal paint and UV paint.

5. The substrate according to claim 1, wherein the metallic material is selected from chromium, silver, copper, and indium, and the metallic compound is optionally obtained in the presence of argon by a gas selected from oxygen, nitrogen, methane, acetylene, and mixtures thereof, provided that the first layer is not made of chromium alone.

6. The substrate according to claim 1, wherein the first layer (10) and / or the second layer (11) and / or the third layer (12) are made of chromium and / or chromium nitride (CrN) and / or chromium carbide (CrC) and / or chromium oxide (CrO) and / or chromium carbonitride (CrCN), provided that the first layer is not made of chromium alone.

7. The substrate according to claim 6, wherein the first layer (10) comprises chromium carbonitride (CrCN) or chromium carbide (CrC).

8. The substrate according to claim 6, wherein the first layer (10) comprises a first portion of a chromium layer deposited on a substrate (100) and a second portion of a chromium carbonitride or chromium carbide layer deposited on the first portion of the chromium layer.

9. The substrate according to claim 6, characterized in that the second layer (11) contains chromium nitride.

10. The substrate according to claim 6, characterized in that the third layer (12) contains chromium, and preferably is made of chromium.

11. The substrate according to claim 1, characterized in that the third layer (12) also includes an agent selected from dopants, dyes, antimicrobial agents and mixtures thereof.

12. The substrate according to claim 1, characterized in that the first layer (10) comprises chromium carbonitride or chromium carbide; the second layer (11) is made of chromium nitride; and the third layer (12) is made of chromium, and optionally supplemented with an agent selected from dopants, dyes, antimicrobial agents and mixtures thereof.

13. A method for producing a coating on a substrate (100) made of a plastic or metal material according to claim 1, using an apparatus (200) for deposition by cathode sputtering, wherein the apparatus (200) for deposition by sputtering comprises at least one vacuum chamber (201), at least one evaporator (204) for a target body (202), and at least one support (203) for the substrate (100), wherein the at least one evaporator (204) and the support (203) are located within the vacuum chamber (201), and the method is as follows: a) A step of placing a printed plastic or metal substrate (100) on the support (203); b) A step of depositing the first layer (10) described in claim 1 onto the substrate by cathode spattering; c) A step of depositing the second layer (11) described in claim 1 onto the first layer (10) by cathode sputtering; and d) A step of depositing the third layer (12) described in claim 1 onto the second layer (11) by cathode sputtering. A method comprising the following: the first layer (10) is made of a material having an elastic modulus of 150 GPa or less, preferably 125 GPa or less; the second layer (11) is made of a material having a hardness of 5.884 MPa (600 Vickers) or more; and the third layer (12) is made of a material having a visible spectrum reflectance of 55 to 70%.

14. The method according to claim 13, wherein, prior to step a), the substrate is painted with a paint selected from thermal paint and UV paint.

15. The method according to claim 13, wherein step b), or step c), or step d) is optionally carried out in the presence of argon, using an ionized or appropriately excited gas selected from oxygen, nitrogen, methane, acetylene, and mixtures thereof as a carrier gas.

16. The method according to claim 13, wherein the target body (20) is selected from chromium, silver, copper, and indium.

17. Use of the coating according to claim 1 to provide a surface crack-free chromized appearance to a printed plastic or metal material support.

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