TWI515333B - Method for forming protective coating layer of magnesium alloy and protective coating layer of magnesium alloy therefrom - Google Patents

Description

Method for forming protective coating on magnesium alloy surface and protective cover layer thereof

The invention relates to a method for forming a protective coating layer on a surface of a magnesium alloy and a protective coating layer thereof, in particular, coating a surface of a crystalline porous ceramic layer of a magnesium alloy with a noble metal catalyst and then electroplating to form a high corrosion resistance. And a method of protecting the coating layer with a metallic luster and a protective covering layer.

Portable electronic products are the mainstream electronic products from the end of the 20th century to the 21st century. Traditional portable electronic products use plastic structural parts in the outer casing or main components, but the strength of plastic structural parts has gradually failed to meet the needs of designers; Aluminum alloy-based structural parts are the mainstream of current portable electronic products. However, aluminum alloy-based structural parts have limitations in weight and processing. Due to the pursuit of lightness and shortness, it is an inevitable trend of portable electronic products. Based on the advantages of light weight, shortness and structural strength, the alloy has heat dissipation, electromagnetic noise interference, light weight, and environmentally friendly waste recycling. Currently, it is widely used in aviation, electronics and vehicle industries. Applications in various industrial sectors are also booming.

There are many different types of applications and applications of magnesium alloys. For example, AM50A or AM60B series magnesium alloys have high elongation and impact resistance, and are often used in aerospace applications and automotive parts. The anti-creep properties of AS41B series magnesium alloys are also good. It is used in aerospace applications; while the magnesium alloy of the AZ91D series has high strength and good corrosion resistance, it is used in the housing of electrical products.

Since the specific gravity of magnesium is 1.8 and the specific gravity of aluminum is 2.7, the weight of magnesium is lighter than that of aluminum; the strength of magnesium is about 20~30Kg/mm ² , which is lower than aluminum, good in workability and extrusion, and can be extruded complicated. The shape is easy to weld and is not brittle at low temperature, high strength under unit weight, and good impact resistance; especially the magnesium alloy has a Damping capacity of about 10 to 25 times that of aluminum alloy and 1.5 times that of zinc alloy. It has high seismic capacity and can absorb large energy when impacted. Therefore, it is an ideal material for manufacturing aviation or electronic products. It can also be used for vibration-sensitive electronic component carriers, shock absorbers and pneumatic tools. .

In the past, the materials of the outer casing of smart phones usually used engineering plastics (such as polycarbonate, polycarbonate (Polycarbonate, PC), Acrylonitrile-Butadiene-Styrene (ABS)) or metal. The casing, but with the increasing size of smart phones and consumers gradually pursuing the trend of thinness and lightness, aluminum alloy materials have the strength of metal, and are light in weight and strong in compression resistance, in mechanical strength and wear resistance. Sexually a temporary choice.

However, the anti-vibration and heat dissipation of aluminum alloy materials are not as good as those of magnesium alloys. If magnesium alloy materials are used in smart mobile phone products, the biggest advantage lies in thermal conductivity and mechanical strength. The hardness is several times that of traditional plastic casings, and magnesium alloys. The outer shell can also be colored into pink blue and pink by surface treatment, which makes the product more beautiful and adds value. Its easy-to-color characteristics are unmatched by engineering plastics, carbon fiber materials and aluminum alloy materials. Because the heat dissipation of magnesium alloy is much better than that of plastic materials, it can transmit a large amount of heat generated by the application processing wafer in the smart phone to the outside world in time; therefore, the mobile phone case of magnesium alloy has received great attention.

Although magnesium alloys have many uses, the Mg ₁₇ Al ₁₂ and the aluminum-rich (α-Al-rich-α) phase on the surface of magnesium alloys cause a Galvanic effect, which is easily oxidized and corroded in humid air, so magnesium Parts made of alloys need to be well surfaced for use, and surface treatment of magnesium alloys is a very important issue.

The surface treatment methods of magnesium alloy are mainly as follows: (1) painting or baking varnish, etc., forming a protective layer on the surface by polymer plastic lacquer to avoid corrosion of magnesium alloy by air and water; (2) chemical formation on the surface The film is formed into a film by chemical or electrochemical treatment to form a film layer containing the metal component. The conventional techniques such as the Taiwan patents TWI352747, TW538138 and the like disclose the chemical conversion treatment; Japanese patent JP2004091826, EPO The chromic acid-based chemical conversion treatment disclosed in the patent EP1657326; the manganic acid chemical conversion treatment disclosed in Japanese Patent JP11100631, Taiwan Patent TW499503; the organic acid chemical conversion treatment disclosed in Taiwan Patent TW555888, TW541354; (3) the surface passivation treatment, such as the Taiwan patent TW I262219 The use of hydrofluoric acid (HF), sulfuric acid (H ₂ SO ₄ ), calcium carbonate (CaCO ₃ ) to passivate the surface of the magnesium alloy to delay corrosion; the method of depositing substances on the surface, there are (4) chemical deposition of metal salts, Such as Chinese patent CN200610030749.6, Taiwan patent publication number TW201212783, Taiwan patent TWI388693, etc.; (5) using thermal diffusion to form metal deposition For example, Taiwan Patent Publication No. TW201041670, TWI388676; (6) a method of impregnating metal oxides, such as Taiwan patent TWI372733.

Or (7) electrochemically plating a layer of metal directly on the magnesium alloy, such as the titanium plating disclosed in Taiwan Patent TWI327178, the titanium-plated zirconium disclosed in TW200821409, Taiwan Patent Publication No. TW201006958, TW2007734680, TW200923127, and Chinese Patent CN21010199946.7. Nickel plating, nickel-plated boron (NiB) exposed by Chinese patent CN200610070858.0; since the plating layer alone can not prevent the corrosion of the substrate alloy, a variety of multi-layer plating techniques have been exposed, in an attempt to cover with a multi-layered gold number. For example, Taiwan patent TWI413483 discloses tin, chromium, chrome-tin alloy and chromium oxynitride (CrNO) on magnesium-tin alloy respectively. Taiwan Patent Publication No. TW201221666 discloses tin, magnesium, magnesium and nitrogen on magnesium-tin alloy. Magnesium (Mg-N), Chinese patent CN200810303204.7 discloses nickel plating on the magnesium alloy, second layer of nickel, copper, nickel and chromium, respectively. The Chinese patents CN200410018471.1 and CN200610047691.6 disclose the magnesium alloy respectively. Nickel plating, zinc, nickel (or zinc), Chinese patent CN200910190902.5 disclosed nickel-phosphorus (NiP) and tantalum carbide (SiC) on magnesium alloy; these are separately powered on magnesium alloy The main principle of the method is to cover the single or multiple layers of metal and non-metal, using dense coating or sacrificial metal to achieve the purpose of protecting the magnesium alloy, but can not effectively reduce the corrosion between the coating and the magnesium alloy. Galvani corrosion.

In addition, the surface treatment method of the magnesium alloy has (8) an oxide forming method, which forms an oxide protective layer on the surface of the magnesium alloy by electrochemical or physical methods, such as the anode treatment disclosed in Taiwan patents TWI266814, TWI297041, TWI342901, and the Chinese patent. CN201010152002.4 uses plasma anodization to form a crystalline porous ceramic layer and then coated with an organic coating for sealing, electroless plating, and nickel plating. Taiwan Patent TW201229270 discloses the use of plasma anodization to form a chromium metal and titanium metal oxide layer.

In another major magnesium alloy surface treatment method: (9) Micro-Arc Oxidation (MAO) method, micro-arc oxidation technology is a new development technology in the 1980s, which can form a crystalline porous ceramic layer on the metal surface. Such as Taiwan Patent Publication No. TW201337037, US U.S. Patent No. 6,808,613, U.S. Patent Application Publication No. Hei. No. Hei. No. Hei. No. Hei. No. Hei. No. Hei. No. Hei. Hei. Hei. Hei. Hei. Hei. Hei. Hei. 7 Adding nano graphite co-deposition; for further post-treatment after micro-arc oxidation treatment, such as Chinese patent CN201010244631.X revealing the use of gel (So-gel) followed by heat treatment, or using polymer for sealing treatment, such as Taiwan Patent Publication No. TW201009122 uses a sol of ethyl citrate as a sealing agent, and Chinese patent CN201310259512.5 uses a tetrahydrofuran solution of polystyrene and maleic anhydride grafted polystyrene as a sealing agent, and Taiwan Patent Publication No. TW201009123 uses organic Tantalum resin is a sealing agent, and Chinese patent CN201210010977.2 uses a decane treatment. However, the surface of the magnesium alloy after micro-arc oxidation is not glossy, and lack of aesthetics is a disadvantage, and if there is no other protection, the weather resistance is still poor.

Therefore, the surface of the magnesium alloy after the micro-arc oxidation is subjected to electroplating, such as the Chinese patents CN200710031650.2, CN201210240758.3, CN200710143623.4, WIPO Patent WO/2006/007972A1, US Patent Publication No. US20140011046, US20120251839 After the MAO, a layer of nickel is electroplated, or as disclosed in Chinese patents CN200610054441.5, CN201110288946.9, and US Patent No. 20100040795, respectively, after sealing with MAO, gel, palladium-free activator, polyester-methacrylate monomer (polyester methacrylate monomer) Then, a layer of nickel or the like is electroplated; as shown in Fig. 1, the first figure is a schematic view of the surface treatment of a conventional magnesium alloy casing. In the figure, the surface treatment of the casing 90 is metal of a metal or a magnesium alloy. On the metallic base substrate 92, a micro-arc oxide layer 94 is formed by a micro-arc oxidation method, and a protective outer film 96 is coated on the surface of the micro-arc oxide layer 94. The protective film 96 is composed of a 5 μm to 10 μm thick coating layer 962 and a metallic layer 964, that is, a portion of the cover layer 962 is removed by laser or other cutting. Electroless plating is applied to the surface of the micro-arc oxidation layer 94 to form a copper layer 9642 of 1 μm to 40 μm thick or a chromium metal layer 9644 of 0.1 μm to 30 μm thick is further formed on the copper metal layer 9642. A metal layer 964 is formed from the copper metal layer 9642 and the chrome metal layer 9644.

The disclosed techniques of the first or the foregoing may cause the surface (or a portion) of the magnesium alloy after micro-arc oxidation to be coated with a metal layer such that the surface (or portion) of the magnesium alloy has a metal. Properties such as chrome gloss, or further plating after sealing, provide better corrosion protection. The surface of the magnesium alloy after micro-arc oxidation (or the surface treated after sealing) has good corrosion resistance, but when the plating solution is soaked and applied, the acid, alkali and various ions of the plating solution will be It penetrates into the micro-arc oxidation layer and gradually forms a high corrosion tendency due to the potential difference of the magnesium alloy. In the environment containing the corrosion factor, the corrosion resistance of the magnesium alloy after micro-arc oxidation is greatly reduced, which requires urgent solution. The problem.

In view of the above problems in the prior art, one of the main objects of the present invention is to provide a method for forming a protective coating on a surface of a magnesium alloy, comprising the steps of: S1: providing a substrate, the substrate being magnesium, magnesium aluminum alloy, magnesium A lithium alloy or a magnesium-aluminum-zinc alloy material, or a substrate composed of magnesium, magnesium aluminum alloy, magnesium lithium alloy or magnesium aluminum zinc alloy, is usually formed by a non-limiting method such as die casting or molding to produce a blank containing the substrate, and then Forming a substrate of a desired size from the blank after processing; S2: forming an oxidized protective layer on the substrate, the oxidized protective layer being composed of crystalline porous ceramic; oxidation protection of the crystalline porous ceramic The layer may be formed by an anodizing method, a micro-arc oxidation method (also referred to as a plasma anodizing method) or a plasma processing method for an unrestricted manner, and the composition may be: (1) magnesium oxide, hydrogen hydroxide. One or a combination of magnesium, aluminum oxide, and aluminum hydroxide, (2) one or a combination of aluminum phosphate, magnesium phosphate, calcium phosphate, (3) one or a combination of aluminum borate, magnesium borate, (4) 矽Aluminum acid, tannic acid One or a combination thereof, (5) magnesium aluminate, magnesium tungstate, magnesium, vanadium, magnesium metavanadate, one or a combination of magnesium sulfate.

Further, after step S2, a step may be added: S21: further coating a surface modifying layer on the oxidized protective layer, the surface modifying layer is coated with a polymer silane polymer, the high The molecular decane polymer is obtained by polymerizing a polymer having a decyl group and a monomer which has a polymer silane which forms a stable covalent bond with the surface of the inorganic substance. For example, the polymer decane polymer may be selected from the group consisting of 3-aminopropyltriethoxysilane (APTES), vinyltrimethoxysilane (VTMS), 3- 3-Aminopropyltrimethoxysilane (APTMS), 4-aminobutyltriethoxydecane (4-Aminobutyltrirthoxysilane, ABTS), N-(β-aminoethyl)-γ-aminopropylmethyldimethoxysilane (N-(2-Aminorthyl)-3-aminopropylmethyldi-methoxysilane, NAAPMDMS), 3- 3-Aminopropylmethyldiethoxysilane (APMDES), 3-Aminopropyldiisopropylethoxysilane (APDIPES), 3-(methacryloxy)oxypropyl A solution of one or a combination thereof of trimethyl methoxysilane (MPS) is dried to form the surface modifying layer, and the polymer decane polymer of the surface modifying layer can form a bond with the surface of the oxidized protective layer. The binding force and the high molecular weight decane polymer of the surface modifying layer can also bond with the nano precious metal chelating agent in the subsequent step, and the nano precious metal chelate layer can be made through the polymer decane polymer of the surface modifying layer. Produces excellent adhesion.

S3: further coating a nano-precious metal chelate layer on the oxidized protective layer (or on the oxidized protective layer of the surface-modified layer), the nano-precious metal chelating layer being composed of a nano-precious metal chelating agent solution After spraying, dipping, printing, forming a nano precious metal chelate layer on the oxidized protective layer by means of an oven or drying or natural drying; wherein the nano precious metal chelating agent solution is an aqueous solution or dispersion of a nano precious metal chelating agent. a solution in a solvent; the noble metal chelating agent is composed of gold (Au), silver (Ag), palladium (Pd), platinum (Pt) or ruthenium (Ru) noble metal particles attached to a polymer chelating agent. The nano precious metal chelating agent has metal catalytic activity; the catalytically active precious metal particles can be combined with the metal plating layer of the subsequent step, so that the metal plating layer can be coated with the oxidized protective layer by the nano precious metal chelating agent (or The substrate coated with the oxidative protective layer of the surface modifying layer produces good coverage.

The polymer chelating agent of the nano precious metal chelating agent has temperature denaturation characteristics, and the temperature denaturation property is hydrophilic in the temperature range of the set nano precious metal chelating agent solution, when the temperature is higher or lower than the nano precious metal chelate The polymer chelating agent is converted to hydrophobicity during the temperature range of the mixture solution.

For a preferred application, the polymer chelating agent of the nano precious metal chelating agent may be one or a combination of the following: A (a copolymer of a polymer monomer (P) and an N-isopropyl acrylamide monomer ( Poly(P-Co-NIPAAmb))), B (Poly(P-hydroxypropylcellulose)), C (polymeric monomer (P) and poly Vinyl caprolactam Copolymer (Poly(P-poly(vinylcaprolactame))), D (Poly(P-poly(vinyl methyl ether))), but not limited to For the above polymer chelating agent, other polymer copolymers can also be easily converted; wherein the polymer monomer (P) can be selected from the following monomer molecules, such as styrene (P1) (Styrene), acrylic acid (P2). (Acrylic acid), Methanacrylic acid (P3), Methyl acrylate or Methyl methacrylate monomer, Ethylene (Ethylene) single One of a monomer, a propylene (P7) (Propylene) monomer, a vinyl chloride (P8) (Vinyl chloride) monomer, or a combination thereof.

S4: forming a first metal layer on the nano precious metal chelate layer, the first metal layer being a nickel metal layer, a copper metal layer, a silver metal layer, a tin metal layer, a palladium metal layer formed by an electroless plating method A gold metal layer or a combination of a plurality of layers of a nickel metal layer, a copper metal layer, a silver metal layer, a tin metal layer, a palladium metal layer, and a gold metal layer formed by electroless plating.

Thus, by this method step, a surface having the characteristics of the first metal layer can be formed on the substrate, so that the substrate can exhibit metal properties of good adhesion, corrosion resistance, and gloss.

Further, after step S4, a step may be added: S6: forming a coating layer by spraying, dipping or printing on the first metal layer, the coating layer being selected from the organic polymer Coating, inorganic enamel coating, organic and inorganic composite coating, anti-fingerprint coating or a combination thereof; by coating the coating layer, the magnesium alloy substrate coated with the first metal layer can further further have the characteristics of the coating layer Such as anti-corrosion, color, aesthetics and anti-fingerprint function.

Anti-fingerprint coating is selected from magnesium fluoride oxide (MgAlO _x F _y ), fluorosilicone, carbon fluoride nitrogen (C _X N _(1-X) F _Y ), fluorinated amorphous germanium dioxide (SiO _X F _Y ), fluorinated amorphous alumina (AlO _x F _y ), polytetrafluoroethylene, cloflucarban, metal oxynitride (MeON) or commercial 3M ^® ECC-4000, KINGFIRST A coating comprising one or a combination of ^® UM-6211; wherein X, Y are numbers; wherein the metal Me of the metal oxynitride is one or a combination of titanium, aluminum, lanthanum, chromium and zirconium.

Further, after step S4, a step may be added: S5: electroless plating, electroplating or evaporation on the first metal layer The second metal layer is a nickel metal layer, a copper metal layer, a silver metal layer, a tin metal layer, a gold metal layer, a base metal layer, a metallized ceramic layer or a plurality of layers thereof; Wherein, the metallized ceramic layer is formed by a co-structured deposition of a metal and a non-metal to form an amorphous phase, wherein the metal may be one of molybdenum, chromium, vanadium, nickel or a combination thereof, and the non-metal may be nitrogen, One or a combination of oxygen or carbon.

The foregoing electroplating method may use an electrochemical electroless plating method, an electroplating method or an evaporation method to form a second metal layer; wherein the evaporation method is plasma-assisted chemical deposition, vapor deposition (CVD), high energy. Micro-arc technology, high temperature carbonization, low temperature carbonization, physical vapor deposition (PVD), powder bath, etc. to form a second metal layer. Thereby, the magnesium alloy substrate coated with the second metal layer can further exhibit metal characteristics of good adhesion, corrosion resistance, and gloss.

The second metal layer is one of a nickel metal layer, a copper metal layer, a silver metal layer, a tin metal layer, a gold metal layer, a base metal layer, and a metallized ceramic layer formed by an electroless plating method, an electroplating method, or an evaporation method. Or multiple layers of each other.

Further, after step S5, a step is added: S6: forming a coating layer on the second metal layer by one of spraying, dipping or printing, the coating layer is selected from the group consisting of organic polymer coatings and inorganic materials.矽 coating, organic and inorganic composite coating, anti-fingerprint coating or a combination thereof; by coating the coating layer, the magnesium alloy substrate coated with the second metal layer can further further have the characteristics of the coating layer, such as corrosion protection Sex, color, aesthetics and anti-fingerprint features.

The aforementioned anti-fingerprint coating may be magnesium fluoride aluminum oxide (MgAlO _x F _y ), fluorosilicone, carbon fluoride nitrogen (C _X N _(1-X) F _Y ), fluorinated amorphous germanium dioxide (SiO _X F _Y ), fluorinated amorphous alumina (AlO _x F _y ), polytetrafluoroethylene, cloflucarban, metal oxynitride (MeON) or commercial 3M ^® ECC-4000, KINGFIRST A coating comprising one or a combination of ^® UM-6211; wherein X, Y are numbers; wherein the metal Me of the metal oxynitride is one or a combination of titanium, aluminum, lanthanum, chromium and zirconium.

One of the main objects of the present invention is to provide a protective coating layer which is coated on a substrate of one or a combination of magnesium, magnesium aluminum alloy, magnesium lithium alloy or magnesium aluminum zinc alloy, the protection The coating layer comprises, in order from the bottom to the surface, an oxidation protective layer, a modified layer, a nano precious metal chelate layer and a first metal layer; Wherein, the oxidative protective layer is composed of a crystalline porous ceramic, and is formed by one of an anodizing method, a micro-arc oxidation method or a plasma processing method, and the composition thereof is preferably one of the following groups or a combination thereof Composition: (1) one or a combination of magnesium oxide, magnesium hydroxide, aluminum oxide, and aluminum hydroxide, (2) one or a combination of aluminum phosphate, magnesium phosphate, calcium phosphate, or (3) aluminum borate, magnesium borate One or a combination thereof, (4) one or a combination of aluminum citrate, magnesium citrate, (5) magnesium aluminate, magnesium tungstate, magnesium vanadate, magnesium metavanadate, magnesium sulfate, or a combination thereof.

Wherein, the surface modification layer is formed by a polymer silane polymer; the surface modification layer is coated with a polymer decane polymer, which is a polymer having a decyl group and is optional. The monomer is polymerized, preferably selected from the group consisting of APTES (3-Aminopropyl) triethoxysilane, VTMS (vinyltrimethoxysilane), APTMS (3-Aminopropyltrimethoxysilane), ABTS (4-Aminobutyltrirthoxysilane), NAAPMDMS (N-(2-Aminorthyl) a solution of one of or a combination of 3-aminopropylmethyldi-methoxysilane, APMDES (3-Aminopropylmethyldiethoxysilane), APDIPES (3-Aminopropyldiisopropylethoxysilane), MPS (3-(Methacryloyloxy)propyltrimethoxysilane).

Wherein, the nano precious metal chelating layer is formed by a nano precious metal chelating agent which is gold (Au), silver (Ag), palladium (Pd), platinum (Pt) or ruthenium (Ru). The noble metal particles are attached to a polymer chelating agent; the polymer chelating agent of the nano precious metal chelating agent has temperature denaturation characteristics; wherein the temperature denaturation characteristic is in the set temperature range of the nano precious metal chelating agent solution Hydrophilic, the polymeric chelating agent transitions to hydrophobicity when the temperature is above or below the temperature range of the nano precious metal chelating agent solution.

Preferably, the polymer chelating agent of the nano precious metal chelating agent is selected from: A (a copolymer of a polymer monomer (P) and an N-isopropyl acrylamide monomer (Poly(P-Co-NIPAAmb). ))), B (Poly(P-hydroxypropylcellulose)), C (polymeric monomer (P) and polyvinyl caprolactam) Copolymer (Poly(P-poly(vinylcaprolactame))), D (Poly(P-poly(vinyl methyl ether))) or a combination thereof The polymer monomer (P) may be selected from the following monomer molecules, such as styrene (P1) (Styrene), acrylic acid (P2) (Acrylic acid), methacrylic acid (P3) (Methacrylic acid), methyl acrylate (P4)(Methyl acrylate) Or one of methyl ethyl methacrylate (P5) (Methyl methacrylate) monomer, ethylene (P6) (Ethylene) monomer, propylene (P7) (Propylene) monomer, vinyl chloride (P8) (Vinyl chloride) monomer or Its combination.

The first metal layer is a nickel metal layer, a copper metal layer, a silver metal layer, a tin metal layer, a palladium metal layer, a gold metal layer or a plurality of layers formed by electroless plating.

Further, for different applications, for a non-limiting manner, a coating layer may be further coated on the first metal layer, the coating layer is coated on the first metal layer or coated on the first metal according to design requirements. a portion of the layer, for example, forming a design pattern; the coating layer is selected from one of an organic polymer coating, an inorganic enamel coating, an organic and inorganic composite coating, an anti-fingerprint coating, or a combination thereof; wherein the anti-fingerprint coating is selected from Magnesium fluoride aluminum oxide (MgAlO _x F _y ), fluorosilicone, carbon fluoride nitrogen (C _X N _(1-X) F _Y ), fluorinated amorphous germanium dioxide (SiO _X F _Y ), fluorine Amorphous alumina (AlO _x F _y ), polytetrafluoroethylene, cloflucarban, metal oxynitride (MeON) or one of the commercial 3M ^® ECC-4000, KINGFIRST ^® UM-6211 Or a combination thereof; wherein X, Y are numbers; wherein metal Me of metal oxynitride is one or a combination of titanium, aluminum, lanthanum, chromium and zirconium.

Still further, for different applications, for a non-limiting manner, a second metal layer may be coated on the first metal layer, the second metal layer covering all or a part of the first metal layer; The second metal layer is one of a nickel metal layer, a copper metal layer, a silver metal layer, a tin metal layer, a gold metal layer, a base metal layer, a metallized ceramic layer formed by an electroless plating method, an electroplating method or an evaporation method or a plurality of layers formed by each other; wherein the metallized ceramic layer is formed by a eutectic stack of a metal and a non-metal co-formed amorphous phase, wherein the metal is one of molybdenum, chromium, vanadium, nickel, or a combination thereof, The metal is one of nitrogen, oxygen or carbon or a combination thereof.

Similarly, for different applications, for a non-limiting manner, a coating layer may be further coated on the second metal layer, the coating layer is coated on the first metal layer or coated on the first metal according to design requirements. a portion of the layer, for example, forming a design pattern; the coating layer is selected from one of an organic polymer coating, an inorganic enamel coating, an organic and inorganic composite coating, an anti-fingerprint coating, or a combination thereof; wherein the anti-fingerprint coating is selected from Magnesium fluoride aluminum oxide (MgAlO _x F _y ), fluorosilicone, carbon fluoride nitrogen (C _X N _(1-X) F _Y ), fluorinated amorphous germanium dioxide (SiO _X F _Y ), fluorine Amorphous alumina (AlO _x F _y ), polytetrafluoroethylene, cloflucarban, metal oxynitride (MeON) or one of the commercial 3M ^® ECC-4000, KINGFIRST ^® UM-6211 Or a combination thereof; wherein X, Y are numbers; wherein metal Me of metal oxynitride is one or a combination of titanium, aluminum, lanthanum, chromium and zirconium.

According to the present invention, a method of forming a protective coating on a surface of a magnesium alloy and a protective coating thereof according to the present invention may have one or more of the following advantages:

(1) The method for forming a protective coating layer on a surface of a magnesium alloy according to the present invention and a protective coating layer thereof, which are formed by a surface formed on a surface of a magnesium alloy substrate by an anode treatment method, a micro-arc oxidation method, or a plasma treatment method. On the oxidized protective layer of porous ceramics, the nano precious metal chelating agent is coated by dipping, spraying, brushing, printing, etc., because the nano precious metal chelating agent is a temperature sensitive polymer with catalytic metal particles attached thereto. The catalytic metal particles are gold (Au), silver (Ag), palladium (Pd), platinum (Pt) or ruthenium (Ru), etc.; the nano precious metal chelating agent used in the present invention has a metallic and nanocrystalline noble metal, It has good catalyst activity, which can make the metal of the first metal layer coated on it have excellent combination, make the first metal layer more uniform and dense, and reduce the corrosion factors of external water, oxygen, ions and the like. Rapid corrosion of the magnesium alloy substrate is caused by corrosion through the first metal layer.

(2) The method for forming a protective coating layer on a surface of a magnesium alloy according to the present invention and a protective coating layer thereof, which are formed by a surface formed on a surface of a magnesium alloy substrate by an anode treatment method, a micro-arc oxidation method, or a plasma treatment method. On the oxidized protective layer of the porous ceramic, a very thin polymer silane polymer is coated by dipping, spraying, brushing, printing, etc., and chemical bonding is formed by the surface of the polymer decane polymer and the oxidized protective layer. After the surface of the substrate is modified, the bond between the surface modification layer and the oxidized protective layer of the substrate can be grasped by the bonding force of the chemical bond to form a better adhesion, and the polymer silane polymer can be sprayed on the surface. The modified layer of nano precious metal chelating agent combines to distribute the nano precious metal chelating agent uniformly, and the formed nano precious metal chelating layer can provide better catalytic activity.

(3) The method for forming a protective coating layer on the surface of a magnesium alloy according to the present invention and a protective coating layer thereof, a nano precious metal chelate layer formed by a nano precious metal chelating agent, and a polymer chelating agent used for a nano precious metal chelating agent In order to have temperature denaturation characteristics and hydrophilicity in the set temperature range, the polymer decane polymer can be well combined with the nano precious metal chelating agent sprayed on the surface modifying layer, but when electroless plating is performed, such as no electricity Nickel plated metal, electroless plating solution The temperature is higher than the hydrophilic temperature range. For example, the electroless plating solution of electroless nickel metal is operated at a temperature of 80 ° C. At this time, the polymer chelating agent is converted into a hydrophobic property, and the nano precious metal chelate layer formed by the nano precious metal chelating agent is formed. It is not destroyed by the electroless plating solution, and the first metal layer formed on the nano precious metal chelate layer has good compactness and better adhesion; thereby forming the first metal layer in addition to providing a surface having a metallic luster In addition, it can provide better corrosion resistance. For example, it can pass the salt spray test of ASTM B117 for 24 hours without rust. It can also meet the weather resistance of 72 hours or more. use.

(4) For example, for many practical needs, such as the need for a brighter metallic color appearance, a golden glare appearance, excellent corrosion resistance, better electrical and thermal conductivity, etc., the present invention forms a protective draped on the surface of the magnesium alloy. The method of coating and the protective coating layer thereof, after forming the first metal layer, further forming a nickel metal layer, a copper metal layer, and a silver of the second metal layer on the first metal layer by using an electroplating method or an evaporation method a metal layer, a tin metal layer, a gold metal layer, a base metal layer, a metallized ceramic layer, etc., may also form a plurality of second metal layers; for example, a gold noble color is required, and silver metal or gold metal may be plated; Corrosion resistance can be electroless, electroplated or vapor deposited with a layer of metallized ceramics. The metallized ceramics are formed by a mixture of metal and non-metal co-structured amorphous phase, which has excellent electrical and corrosion resistance properties; The need for heat conduction can be coated with nickel metal, copper metal, silver metal, tin metal, gold metal, metallized ceramics, and the like.

(5) The method for forming a protective coating layer on the surface of a magnesium alloy according to the present invention and the protective coating layer thereof, since the first metal layer or even the second metal layer has good compactness, corrosion resistance and functionality, according to the appearance requirement , anti-corrosion function requirements, anti-fingerprint requirements, non-conductivity requirements, etc., can be coated on the first metal layer or the second metal layer to form a coating layer, by organic polymer coating, inorganic antimony coating, anti-fingerprint coating, etc. Achieve the aforementioned needs.

(6) The method for forming a protective coating layer on a surface of a magnesium alloy according to the present invention and a protective coating layer thereof. If the second metal layer is coated, a patterned partial coating is adopted to make the second metal layer have a pattern. The function of forming a circuit line, a metallic luster trademark, typeface, graphics, etc. on a magnesium alloy substrate, and expanding the magnesium alloy in the communication base station, the LED heat sink, the steering wheel of the steam locomotive, the decorative part or the hub, and the medical Applications of equipment, electronic product enclosures, housings and internal components of mobile phone products.

For a better understanding of the features and technical aspects of the present invention, reference should be made to the accompanying drawings.

1‧‧‧substrate

2‧‧‧protective coating layer

21‧‧‧oxidation layer

211‧‧‧microarc oxidation (MAO) equipment

22‧‧‧chemical modified layer

221‧‧‧ polymer silane polymer

23‧‧‧nano-scale noble metal chelated layer

231‧‧‧nano-scale noble metal chelate agent

24‧‧‧first metal layer

241‧‧‧electroless plating equipment

25‧‧‧second metal layer

251‧‧‧electroplating equipment

26‧‧‧paint layer

261‧‧‧paint equipment

3‧‧‧mobile phone

31‧‧‧ housing

32‧‧‧ internal components (baffle)

321‧‧‧conductive contact (conduct contact)

4‧‧‧Server rack

41‧‧‧Rack plate (flame)

5‧‧‧computer

51‧‧‧outer casing

511‧‧‧pattern

6‧‧‧Camera

61‧‧‧body (fuselage)

7‧‧‧circuit board

71‧‧‧conductive circuit

8‧‧‧LED heat sink fine

90‧‧‧Cabinet

92‧‧‧metallic base substrate

94‧‧‧micro-arc oxide layer

96‧‧‧protective outer film

962‧‧‧coating layer

964‧‧‧metal layer

9642‧‧‧copper layer

9644‧‧‧Chromium metal layer

1 is a schematic view showing the surface treatment of a conventional magnesium alloy casing; FIG. 2 is a step view showing a method for forming a protective coating on the surface of a magnesium alloy according to the present invention; and FIG. 3 is a surface protection of the magnesium alloy according to the present invention. Schematic diagram of a method of coating a layer; FIG. 4 is a schematic view showing a first embodiment of a method for forming a protective coating layer on a surface of a magnesium alloy and a protective coating layer thereof; and FIG. 5 is a surface of the magnesium alloy of the present invention. A method for forming a protective coating layer and a schematic diagram of a second set of embodiments for protecting the coating layer; FIG. 6 is a third method of forming a protective coating layer on the surface of a magnesium alloy according to the present invention and a protective coating layer thereof BRIEF DESCRIPTION OF THE DRAWINGS FIG. 7 is a schematic view showing a method for forming a protective coating layer on a surface of a magnesium alloy according to the present invention and a fourth embodiment of the protective coating layer; and FIG. 8 is a view showing a protective coating on the surface of the magnesium alloy according to the present invention; The method of layer and the schematic diagram of the sixth group embodiment of the protective coating layer; the figure 9 is a schematic diagram of the seventh group of embodiments for forming a protective coating layer on the surface of the magnesium alloy and the protective coating layer thereof; The figure is the invention The method of forming the protective alloy surface cladding layers and the cladding layer is a schematic view of an eighth embodiment of the protective group.

Schema attachment

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is an attenuated total reflection (ATR) diagram of an oxidized protective layer of a first set of embodiments of the present invention; Figure 2A of the accompanying drawings is a modified surface layer of a first set of embodiments of the present invention Photograph of the substrate of the chelate layer with nano precious metal; Figure 2B of the attached figure is a cross-sectional photograph of the substrate of the coating surface modifying layer and the nano precious metal chelate layer of the first group of embodiments of the present invention; 3A is a first embodiment of the present invention, the substrate coated with the first metal layer Photograph; FIG. 3B is a cross-sectional photograph of a substrate coated with a first metal layer according to a first group of embodiments of the present invention; and FIG. 4 is a draping of a first group of embodiments of the present invention. X-ray photoelectron spectroscopy (XPS) image of a metal layer substrate.

It has been found by many scholars and inventors that magnesium alloys are magnesium alloys formed by adding different metal elements to magnesium metal, and the added metal elements form a second phase of the structure, which has a great influence on the corrosion of the magnesium alloy. In the foregoing, although the Mg ₁₇ Al ₁₂ on the surface of the magnesium alloy is inert in the environment containing chloride ions, the Mg ₁₇ Al ₁₂ and the aluminum-rich (α-Al-rich-α) phase on the surface of the magnesium alloy may cause The Galvani effect is easily oxidized and corroded in humid air; it is different between the Mg ₁₇ Al ₁₂ and the Al-rich-α phase due to the different Electrolytic Solutional tension. The difference between the Galvanic Potential (or the electrolysis potential) forms a battery effect and produces a corrosion current. As a result of this battery effect, the anode is dissolved and etched by the higher potential metal due to the passage of current (from the anode to the cathode). . When the potential difference is larger, the stronger the generated current, the greater the corrosion loss rate. In particular, in an environment with ions (such as exposure to moisture), the corrosion current will move and accelerate the corrosion.

In the prior art, the magnesium alloy may be formed into a crystalline porous ceramic magnesium oxide compound, a phosphoric acid compound, a boric acid compound or a tannic acid compound by an anodizing method, a micro-arc oxidation method or a plasma treatment method, and the like. The protective layer formed by the compound on the surface of the magnesium alloy is inherently resistant to corrosion, and the use of the primer layer for the coating layer is a conventional practice. However, the ceramic structure of these magnesium oxygen compounds, phosphoric acid compounds, boric acid compounds or phthalic acid compounds lacks flatness, metallic color and gloss, and lacks heat conduction, electrical conductivity or metallic texture in addition to loss of appearance. In combination with other conventional techniques, for example, metallization or electroless plating on the surface of these magnesium oxygen compounds, phosphoric acid compounds, boric acid compounds or phthalic acid compounds, although an alternative surface treatment method, however, When the surface of the magnesium oxygen compound, phosphoric acid compound, boric acid compound or citric acid compound is in contact with the acid, base, anion or cation of the plating solution, these acids, bases, anions or cations are coated on the plated metal layer and crystallized. Between the porous ceramic layers, once the external corrosion factor penetrates, the corrosion of the magnesium alloy is accelerated. The crystalline porous ceramic layer, which can withstand the salt spray test of 96 hours or more, will be quickly reduced to a salt spray test which can only withstand 4 to 12 hours after plating the metal.

Another important corrosion mechanism comes from the corrosion potential difference between the electroplated metal and the magnesium alloy substrate, although the magnesium oxide compound, the phosphoric acid compound, the boric acid compound or the tannic acid compound crystal porous ceramic between the electroplated metal and the magnesium alloy substrate. The layers are spaced apart, but the magnesium alloy is affected by the difference in corrosion potential. The electrons in the magnesium alloy will rapidly flow to cause rapid corrosion, resulting in a crystalline porous ceramic layer that can withstand a salt spray test of 96 hours or more. After plating the metal, it will be quickly reduced to a salt spray test that can only withstand 4 to 12 hours.

How to reduce the corrosion of magnesium alloy gamma-nibon, resist the reaction corrosion of magnesium alloy and external water vapor, oxygen and ion contact and make the plating metal excellent, so that the crystalline porous ceramic layer coated with metal can be improved. To the industrial salt spray test for more than 24 hours and even up to 72 hours or more, is one of the motives of the present invention.

Please refer to the second and third figures. FIG. 2 is a flow chart showing the steps of the method for forming a protective coating on the surface of the magnesium alloy according to the present invention, and FIG. 3 is a view showing the formation of a protective coating on the surface of the magnesium alloy according to the present invention. Schematic diagram of the method: For workpieces made of magnesium, magnesium aluminum alloy, magnesium lithium alloy or magnesium aluminum zinc alloy, the blank is usually made by die casting or molding, and then the size required for the workpiece is processed by the blank. The substrate 1 is commonly used in electronic products, automobile and motorcycle components, optical products, etc.; the protective coating layer 2 on the substrate 1 can be formed by using an anodizing method, micro-arc oxidation on the substrate 1 The method or the plasma treatment method forms an oxidation protection layer 21, and in the subsequent embodiment, the micro-arc oxidation method is used to form the oxidation protection layer 21 by using the micro-arc oxidation apparatus 211, for other anode treatment methods, plasma treatment methods or plasma anodes. The oxidation method is similar and not limited; in different micro-arc oxidation solutions, different compositions can be formed: (1) magnesium oxide, magnesium hydroxide, aluminum oxide, aluminum hydroxide, and (2) phosphoric acid. Aluminum, magnesium phosphate, calcium phosphate, (3) aluminum borate, magnesium borate, (4) aluminum citrate, magnesium citrate, (5) magnesium aluminate, magnesium tungstate, magnesium vanadate, magnesium metavanadate, magnesium sulfate An oxidized protective layer 21 of one or a combination thereof.

If the anode treatment method is used, the substrate 1 is placed in an electrolyte, and the substrate 1 is used as an anode, a titanium alloy or a lead plate is used as a cathode, and a current of 3 to 10 A/dm ^{2 is used} for treatment for 5 to 120 minutes using a rectifier. (required for film thickness), wherein the electrolyte is usually an alkaline solution, which is a hydroxide, trisodium phosphate, sodium metasilicate, oxalic acid or a salt thereof, a fatty acid or a salt thereof, etc. A crystalline porous ceramic layer formed of magnesium oxide and magnesium niobate forming dense and fine pores.

If the micro-arc oxidation method is adopted, the method includes the steps of: de-fatting the substrate 1 into an alkaline degreasing agent (or an organic solvent) for about 10 minutes to remove the grease and other deposits on the substrate 1, and the substrate 1 is degreased and washed. The water-washed substrate 1 is placed in an electrolytic solution of the micro-arc oxidation device 211 for micro-arc oxidation treatment; the electrolytic solution may be a solution of an oxalate (hydroxide) solution system, a solution of a phosphate system, or a borate a solution of the system, a solution of a citrate system, a solution of an aluminate system or a mixture of these, the electrolytic solution may contain additives such as tungstate, vanadate, ammonium metavanadate, sulfate, fluorine A wetting agent such as a sodium salt, a cobalt salt, an organic alcohol or an ester.

In the micro-arc oxidation treatment, the substrate 1 is used as the anode, the titanium alloy, the stainless steel or the lead plate cathode, and the exchange electric field is generated on the substrate 1 by the positive and negative bidirectional pulse voltages, and the positive and negative bidirectional pulse voltages are usually +400V~+600V, -30V~-200V, The time for micro-arc oxidation treatment is 30 to 120 minutes (adjusted according to thickness requirements). In the electric field, the substrate 1 dissolves magnesium, magnesium, aluminum, etc., and the crystalline porous ceramic layers of magnesium and aluminum and salts, such as magnesium oxide and hydroxide, can be formed on the substrate 1 due to conversion and deposition of salts of the electrolytic solution. Magnesium, alumina, aluminum hydroxide, aluminum phosphate, magnesium phosphate, calcium phosphate, aluminum borate, magnesium borate, aluminum citrate, magnesium citrate, magnesium aluminate, magnesium tungstate, magnesium vanadate, magnesium metavanadate, sulfuric acid Magnesium, etc.

Next, a solution (aqueous solution or solvent solution) of the nano precious metal chelating agent 231 is sprayed (or coated, printed, immersed, etc.) on the entire surface or a part of the surface by spraying, dipping, printing, or the like on the oxidized protective layer 21. If a part of the whole or a specific large area is used, a solution of the nano precious metal chelating agent 231 may be coated with a whole or a large area by spraying or dipping; if it is a set pattern or a small part, Using a non-limiting printing method such as a stamping method, a printing method, an inkjet method, and a brushing method, a specific pattern or a fine portion is coated with a nano precious metal chelating agent 231; and then used in an oven or blown dry or naturally dried. Alternatively, a nano precious metal chelate layer 23 is formed on the oxidized protective layer 21.

The pattern or the fine portion printed on the oxidized protective layer 21 may be a trademark pattern, a beautification pattern, a symbol pattern, a character pattern or a circuit pattern, etc., and the printing method may be performed by using a plate-making printing machine for printing and pad printing. , offset press for injection or printer The method of inkjet printing or the like is not limited, and the purpose thereof is to transfer the solution of the nano precious metal chelating agent 231 to the surface of the oxidation protection layer 21; in the subsequent drawings or embodiments, the inkjet printing is carried out by a printer, but Not limited to this.

The solution of the nano precious metal chelating agent 231 is an aqueous solution of a nano precious metal chelating agent or a solution dispersed in a solvent; the nano precious metal chelating agent 231 is gold (Au), silver (Ag), palladium (Pd), platinum ( The noble metal particles of Pt) or ruthenium (Ru) are adhered to a polymer chelating agent, and one end of the nano precious metal chelating agent 231 is a polymer chelating agent, which can be well covered on the oxidized protective layer 21 and adhered to the oxidized protective layer 21 The other end of the nano precious metal chelating agent 231 is a noble metal particle of gold (Au), silver (Ag), palladium (Pd), platinum (Pt) or ruthenium (Ru), and can be combined by using catalytically active noble metal particles. The metal plating layer of the subsequent step enables the metal plating layer to be well covered by the nano precious metal chelating agent 231 and the substrate 1 coated with the oxidized protective layer 21.

The polymer chelating agent of the nano precious metal chelating agent 231 has been studied by the present inventors for a long time, preferably one of the following or a combination thereof: A (polymer monomer (P) and N-isopropyl acrylamide monomer) Copolymer (Poly(P-Co-NIPAAmb)), B (Poly(P-hydroxypropylcellulose)), C (polymer monomer) Copolymer with polyvinyl caprolactam (Poly(P-poly(vinylcaprolactame))), D (copolymer of polymer monomer (P) and polyvinyl methyl ether (Poly(P-poly(vinyl) Methyl ether))), but not limited to the above-mentioned polymer chelating agent, other polymer copolymers can also be easily converted; wherein the polymer monomer (P) can be selected from the following monomer molecules, such as styrene ( P1) (Styrene), Acrylic acid (P2), Methacrylic acid, Methyl acrylate or Methyl methacrylate Body, ethylene (P6) (Ethylene) monomer, propylene (P7) (Propylene) monomer, vinyl chloride (P8) (Vinyl chloride) monomer, but not limited to the above-mentioned polymer monomer, other polymer single body It can be easily converted to use.

For other nano precious metal chelating agents 231, the noble metal may be catalytically active gold (Au), silver (Ag), palladium (Pd), platinum (Pt) or ruthenium (Ru), if the precious metal is selected from metal palladium, polymer The monomer (P) is selected from a styrene (P1) (Styrene) monomer, and the nano precious metal chelating agent 231 is formed by using palladium (Pd) attached to the polymer chelating agent to form, for example, Pd-Poly (Styrene-Co-NIPAAmb). , Pd-Poly (Styrene-hydroxypropylcellulose), Pd-Poly (Styrene-Poly (vinylcaprolactame)), Pd-Poly (Styrene-Poly (vinyl methyl) Ether)).

Copolymer (Pd-Poly (Styrene-Co-NIPAAmb)) of a styrene monomer to which a nano precious metal palladium is attached (Pd-Poly (Styrene-Co-NIPAAmb)) For the preparation and characteristics, see "Wen-Ding Chen et. al., The preparation of thermo-responsive palladium catalyst with high activity for electroless nickel deposition, Surface and Coating Technology 204 (2010) P.2130-2135" and Taiwan patents. I324616, Preparation and characteristics of hydroxypropylcellulose can be found in "A. Kagemoto, Y. Baba, Kobunshi Kagaku, 1971, Volume 28, p 784."; Polycaprolactam (Poly(vinylcaprolactame)) For preparation and properties, see "Y. Maeda, T. Nakamura, I. Ikeda, Hydration and Phase Behavior of Poly (N-vinylcaprolactam) and Poly (N-vinylpyrrolidone) in Water, Macromolecules, 2002, Volume 35, pp 217 -222."; Preparation and characteristics of Poly(vinyl methyl ether) can be found in "HGSchild, DA Tirrell, Microcalorimetric Detection of Lower Critical Solution Temperatures in Aqueous Polymer Solutions, Journal of Physical Chemistry, 1990, Volume 94, pp 4352-4356.".

The polymer chelating agent of the aforementioned nano precious metal chelating agent 231 has temperature denaturation characteristics, and the temperature denaturation property is hydrophilic in the temperature range of the set nano precious metal chelating agent 231, when the temperature is higher or lower than the nano precious metal chelate. In the temperature range of mixture 231, the polymer chelating agent is converted into hydrophobic; Pd-Poly (Styrene-Co-NIPAAmb) is described as a nano-precious metal chelating agent 231, and Pd-Poly (Styrene-Co-NIPAAmb) is hydrophilic at normal temperature. Sexuality, gradually changing to hydrophobicity above 33 °C. When the nano precious metal chelating agent 231 is sprayed on the oxidized protective layer 21, the nano precious metal chelating agent 231 can be combined with the oxidized protective layer 21, but when electroless nickel plating is performed, the electroless plating of the electroless plating nickel metal is performed. The temperature is 80 ° C, at which time the polymer chelating agent is converted to hydrophobicity, so that the nano precious metal chelate layer 23 formed by the nano precious metal chelating agent 231 is not destroyed by the electroless plating solution, and the first metal layer 24 is good. The compactness and better adhesion; the first metal layer 24 formed thereby provides better corrosion resistance and is compatible with industrial products.

a magnesium alloy base coated with the oxidation protective layer 21 of the nano precious metal chelating agent 231 The first metal layer 24 is formed by electroless plating, and the first metal layer 24 may be a nickel metal layer, a copper metal layer, a silver metal layer or a tin metal layer. a palladium metal layer, a gold metal layer, or the like, or the foregoing metal layer may be formed by an electroless plating method, and then a second layer or a plurality of layers may be formed by one or a combination of an electroless plating method, an electroplating method, or an evaporation method. Nickel metal layer, copper metal layer, silver metal layer, tin metal layer, palladium metal layer, gold metal layer. In the subsequent embodiments, electroless nickel and electroless copper are used for the purpose of comparison, but not limited thereto. So far, the protective coating layer 2 on the substrate 1 includes the oxidized protective layer 21, the nano precious metal chelating layer 23, and the first metal layer 24.

Since the first metal layer 24 is coated, a surface having the characteristics of the first metal layer 24 can be formed on the substrate 1 of the magnesium alloy, so that the substrate 1 is covered with the protective coating layer 2 to exhibit good adhesion and corrosion resistance. , shiny metallic properties.

For thicker protective requirements or appearance, anti-fingerprint surface requirements, the first metal layer 24 may be sprayed, dipped or printed, such as by using a painting equipment 261 to organic polymer coatings, inorganic enamel coatings, organic and inorganic composites. After the coating and the anti-fingerprint coating are sprayed, the coating layer 26 is formed, and the coated magnesium alloy substrate 1 can be further coated with the coating layer 26 to further have the characteristics of the coating layer 26, such as corrosion resistance. The function of color, aesthetics and anti-fingerprint; thus, the protective coating layer 2 on the substrate 1 comprises an oxidation protective layer 21, a nano precious metal chelate layer 23, a first metal layer 24 and a further coating layer 26.

Further, the aforementioned painting equipment 261 can be a commonly used spray gun type (as shown in the drawing). For the finely patterned paint layer 26, printing, brushing, transfer, glue injection, etc. can be used, For the limit.

The coating layer 26 can be selected from organic polymer coatings, inorganic enamel coatings, organic and inorganic composite coatings, anti-fingerprint coatings, etc., among which organic polymer coatings such as vinyl acetate coatings, acrylic coatings (commonly known as acrylic resin coatings), and epoxy Resin coatings, polyurethane resin coatings, organic silicone resin coatings (such as polyoxyalkylene-amino resin coatings) are not limited; inorganic coatings such as inorganic tantalum resin coatings, SiO ₂ gels (so-gel), etc. The organic and inorganic composite coatings such as aluminum-doped zinc oxide coatings, zinc-aluminum powders and organic resins (such as WISCO 850, wellzinc 850) are not limited, and their corrosion resistance is derived from aluminum. Shadow protection and zinc sacrificial protection.

Especially for electronic products such as mobile phones or tablets, the anti-fingerprint surface requirement is one of the functions introduced in the industry. Anti-fingerprint coatings can use magnesium fluoride aluminum oxide (MgAlO _x F _y ), fluorosilicone, fluorination. Carbon nitrogen (C _X N _(1-X) F _Y ), fluorinated amorphous cerium oxide (SiO _X F _Y ), fluorinated amorphous alumina (AlO _x F _y ), polytetrafluoroethylene, a coating comprising one or a combination of cloflucarban, metal oxynitride (MeON) or commercial 3M ^® ECC-4000, KINGFIRST ^® UM-6211; wherein X, Y are numbers; wherein metal oxynitride The metal Me is one of titanium, aluminum, bismuth, chromium and zirconium or a combination thereof.

In many products, the anti-corrosion requirements are high. For example, it is required to pass the salt spray test of ASTM B117 for 24 to 72 hours without rust. The crystal can be formed in the anode treatment method, micro-arc oxidation method or plasma treatment method. After the oxidized protective layer 21 of the ceramic, the upper surface modifying layer 22 is coated on the oxidized protective layer 21. The surface modifying layer 22 is formed by coating the oxidized protective layer 21 with the polymer decane polymer 221, and the polymer decane polymer 221 of the surface modifying layer 22 can generate a bonding force with the surface of the oxidized protective layer 21, and The polymer decane polymer 221 of the surface modifying layer 22 can also generate a bonding force with the nano precious metal chelating agent 231 of the subsequent step, and the nano precious metal chelate layer 23 can be passed through the polymer decane polymer of the surface modifying layer 22. Producing excellent adhesion, the first metal layer 24 coated on the nano precious metal chelate layer 23 can be more easily formed uniformly, the first metal layer 24 is more dense, and the corrosion resistance of the first metal layer 24 is increased. It reduces the penetration of external corrosion factors and blocks the loss of electrons from the substrate 1.

The polymer decane polymer 221 is a polymer obtained by polymerizing a polymer having a decyl group and an optional monomer. After long-term research, a surface modifying layer 22 having a good bonding force can be formed on the oxidized protective layer 21. And can form excellent adhesion with the nano-precious metal chelate layer 23, preferably 3-aminopropyltriethoxysilane (APTES), vinyltrimethoxysilane (vinyltrimethoxysilane) , VTMS), 3-Aminopropyltrimethoxysilane (APTMS), 4-aminobutyltrirthoxysilane (ABTS), N-(β-aminoethyl)-γ -N-(2-Aminorthy1)-3-aminopropylmethyldi-methoxysilane, NAAPMDMS, 3-Aminopropylmethyldiethoxysilane, APMDES, 3 -aminopropyldiisopropylethoxy The surface modifying layer 22 is formed by drying, 3-Aminopropyldiisopropylethoxysilane (APDIPES), 3-(Methacryloyloxy)propyltrimethoxysilane (MPS).

Similarly, as in the foregoing method, a solution of the nano precious metal chelating agent 231 may be sprayed on the surface of the surface modifying layer 22 by spraying, dipping, printing, or the like to form a nano precious metal chelate layer on the entire surface or a part of the surface. Further, electroless plating is performed on the nano precious metal chelate layer 23 to form a nickel metal layer, a copper metal layer, a silver metal layer, a tin metal layer, a palladium metal layer, a gold metal layer or a plurality of first metal layers 24 thereof. So far, the protective coating layer 2 on the substrate 1 includes the oxidation protecting layer 21, the surface modifying layer 22, the nano precious metal chelate layer 23 and the first metal layer 24.

The coating layer 26 may be formed on the first metal layer 24 by spraying, dipping or printing on the first metal layer 24 with an organic polymer coating, an inorganic enamel coating, an organic and inorganic composite coating, and an anti-fingerprint coating. Thus, the protective overcoat layer 2 on the substrate 1 comprises the oxidized protective layer 21, the surface modifying layer 22, the nano precious metal chelating layer 23, the first metal layer 24 and the coating layer 26; or on the first metal layer The second metal layer 25 is formed by an electroless plating method, an electroplating method, or an evaporation method.

The second metal layer 25 is a nickel metal layer, a copper metal layer, a silver metal layer, a tin metal layer, a gold metal layer, a base metal layer, a metallized ceramic layer or a plurality of layers thereof, which can form a second surface for the entire surface. The metal layer 25, or using selective plating, has the second metal layer 25 patterned or lined, as in the subsequent embodiments; wherein the nickel metal layer, the copper metal layer, the silver metal layer, the tin metal layer, and the gold metal layer are often Electroless plating using plating bath 251, or electroless plating, physical plasma assisted chemical deposition, vapor deposition (CVD), high energy microarc technology, high temperature carbonization, low temperature carbonization, physical vapor deposition ( Formed by PVD), powder bath, etc. Thereby, the magnesium alloy substrate 1 coated with the second metal layer 25 can exhibit metal properties of good adhesion, corrosion resistance, and gloss. So far, the protective coating layer 2 on the substrate 1 includes the oxidation protecting layer 21, the surface modifying layer 22, the nano precious metal chelate layer 23, the first metal layer 24 and the second metal layer 25.

For the metallized ceramic layer, the electrochemical method of forming a chromium carbide-based cermet layer disclosed in Taiwan Patent Publication No. TW201339373 can be used to electroplate a metal of molybdenum, chromium, vanadium, nickel and a non-metal of nitrogen, oxygen or carbon by electroplating. A co-structured co-structured amorphous phase is formed, wherein the metallized ceramic layer of the carbon and chromium co-structure has metallic luster and height Corrosion-resistant properties and high electrical conductivity enhance the application of magnesium alloy protective coatings.

Similarly, for thicker protective requirements or appearance, anti-fingerprint surface requirements, as described above, the organic polymer coating can be applied to the second metal layer 25 by spraying, dipping or printing methods, such as using a painting equipment 261. The inorganic enamel coating, the organic and inorganic composite coating, and the anti-fingerprint coating are applied to form the coating layer 26, and the coated coating layer 26 further enables the substrate 1 of the magnesium alloy coated with the second metal layer 25 to have a coating. The characteristics of layer 26, such as corrosion resistance, color, aesthetics and anti-fingerprint function. So far, the protective coating layer 2 on the substrate 1 includes the oxidation protecting layer 21, the surface modifying layer 22, the nano precious metal chelate layer 23, the first metal layer 24, the second metal layer 25, and the coating layer 26.

A plurality of sets of embodiments will be enumerated hereinafter, and there are several different combinations of each set of embodiments to further illustrate the application of the present invention.

<First Group of Embodiments>

Referring to FIG. 4, FIG. 4 is a schematic view showing the first group of embodiments of the present invention for forming a protective coating on a substrate of a magnesium alloy by using the method of the present invention, which is applied to a mobile phone casing; The outer casing 31 of the telephone 3 is formed with a protective covering layer 2 made of a magnesium-aluminum alloy (AZ91D), and a substrate 1 of magnesium-aluminum alloy is produced by a molding method. The main process requirements of the outer casing 31 of the mobile phone 3 are to have a metallic luster texture, and the anti-corrosion requirements before unpainting are required to pass the ASTM B117 5% salt spray test for more than 36 hours without rust corrosion, the surface is first coated with organic paint or can be re-coated. Apply anti-fingerprint coating.

The protective coating layer 2 on the substrate 1 of the present embodiment is composed of the following, first forming an oxidation protection layer 21 on the substrate 1 by the micro-arc oxidation device 211 or other equipment, and the main component of the oxidation protection layer 21 is magnesium oxide. Further, it contains a crystalline porous ceramic such as alumina, magnesium hydroxide or aluminum hydroxide, and has a thickness of 8 to 10 μm.

The substrate 1 to which the oxidized protective layer 21 is attached is immersed in an ethanol solution of the polymer decane polymer 221, and taken out and dried at 50 ° C to form a surface modifying layer 22, see Fig. 1 of the attached figure, Fig. 1 of the attached figure An attenuated total reflection (ATR) pattern of the oxidized protective layer of the present embodiment, as shown in the figure, a polymer decane polymer 221 (abbreviated as silane on the drawing) is coated on the substrate 1 (abbreviated as base on the figure) )on.

Further, the base of the surface modifying layer 22 and the oxidized protective layer 21 is attached by spraying. The plate 1 is coated with an aqueous solution of the nano precious metal chelating agent 231, and dried at 35 ° C to form a nano precious metal chelate layer 23; please refer to the attached figure 2, the attached figure 2A and the attached figure 2B The photographs are photographs and cross-sectional photographs of the substrate 1 coated with the surface modifying layer 22 and the nano precious metal chelate layer 23, respectively, and the crystal porous and cross-sectional thickness of the oxide protective layer 21 is shown as 9.11 μm in the oxidation protection. The polymer decane polymer 221 and the nano precious metal chelating agent 231 on the layer 21 are too thin to be displayed in two photographs.

Then, the substrate 1 to which the nano precious metal chelate layer 23, the surface modifying layer 22, and the oxidation protecting layer 21 are attached is immersed in the electroless plating bath 241 to perform an electroless plating reaction, for example, electroless nickel plating or no electricity in the embodiment. Electroplating copper to form a first metal layer 24; see Figures 3A and 3B of the attached drawings, and Figures 3A and 3B of the attached drawings are photographs and cross-section photographs of the substrate 1 covering the first metal layer 24, respectively. As can be seen from the photograph, the first metal layer 24 is uniformly and densely coated on the substrate 1 on the surface modifying layer 22 and the nano precious metal chelate layer 23, and the first metal layer 24 is photographed as 11.68 μm. Please refer to FIG. 4 of the attached figure. FIG. 4 is a diagram of an X-ray photoelectron spectroscopy (XPS) of the substrate of the first metal layer 24 according to the third embodiment of the present invention. The first metal layer 24 has a nickel layer thickness of about 10 to 12 μm.

In order to have a smoother and smoother metal surface, the substrate 1 (with the nano precious metal chelate layer 23, the surface modifying layer 22 and the oxidized protective layer 21 attached) coated with the first metal layer 24 is placed in the plating bath. Electroplating is performed in 251 (or electroless plating if immersed in the electroless plating bath 241) to form the second metal layer 25. For further appearance requirements, the organic coating material is sprayed on the surface of the second metal layer 25 by the painting equipment 261 to form a coating layer 26, and further, the anti-fingerprint coating is sprayed on the surface of the coating layer 26.

In the embodiment of the present invention, the protective coating layer 2 of the first metal layer 24 formed on the outer casing 31 of the magnesium alloy material of the mobile phone 3 is formed by the method for forming a protective coating layer on the surface of the magnesium alloy of the present invention. In addition to having the adhesion of 5B (ASTM-3359), it can pass at least the ASTM B117 5% salt spray test for more than 36 hours without rusting, and further, the second metal layer 25 formed by electroplating on the first metal layer 24. The protective covering layer 2 can have the bright texture of chrome metal, the low-key metal texture of the metallized ceramic CrC or the noble gold texture of the gold metal, and can pass the ASTM. B117 5% salt spray test for more than 36 hours without rust corrosion requirements (this embodiment can be at least 72 hours), in addition to the second metal layer 25 can be repainted with various colors of organic paint, or can be repainted Anti-fingerprint coating.

The method for forming a protective coating layer on the surface of the magnesium alloy of the present invention and the protective coating layer 2 formed on the outer casing 31 of the magnesium alloy material of the mobile phone 3 by using the method have excellent corrosion resistance characteristics, and Beyond the basic needs of use.

<Second Group of Embodiments>

Referring to FIG. 5, FIG. 5 is a schematic view showing a second set of embodiments of the present invention for forming a protective coating on a substrate of a magnesium alloy by using the method of the present invention, which is applied to a mobile phone internal component; The inner member 32 of the mobile phone 3 constitutes a protective covering layer 2, and the inner member 32 is made of a magnesium-lithium alloy (LZ91), and the substrate 1 of the magnesium-aluminum alloy is formed by a molding method. The main process requirements of the inner member 32 of the mobile phone 3 are the anti-corrosion requirements before the unpainting. The organic coating which has been subjected to ASTM B117 5% salt spray test for more than 36 hours without corrosion, conductive contacts, and surface coating insulation.

The protective coating layer 2 on the substrate 1 of the present embodiment is first composed of an oxidation protective layer 21, a surface modifying layer 22, a nano precious metal chelate layer 23, and a first metal layer 24. The embodiment is not described here.

The first metal layer 24 is selectively shielded, leaving only the portion of the first metal layer 24 coated with the first metal layer 24 (with the nano precious metal chelate layer 23 attached, not leaving the portion of the conductive contact 321 unobstructed). The surface modifying layer 22, the oxidized protective layer 21 and the selectively shielded first metal layer 24) are immersed in the electroless plating bath 241 to perform an electroless plating reaction to form the second metal layer 25; and the first metal layer is further formed. 24 rows of selective shielding portions are removed, and the portion relative to the conductive contacts 321 is shielded, and the paint coating device 261 sprays the organic coating on the surface of the first metal layer 24 to form a coating layer 26, which is torn off. The shield of the portion of the conductive contact 321 forms the inner member 32 of the conductive contact 321 having the partial second metal layer 25 of the present embodiment.

In the present embodiment, the protective coating layer 2 of the first metal layer 24 formed on the magnesium-aluminum alloy inner member 32 of the mobile phone 3 is formed by the method of forming the protective coating layer on the surface of the magnesium alloy of the present invention. In addition to the adhesion of 5B (ASTM-3359), it can pass at least the ASTM B117 5% salt spray test for more than 36 hours without rusting, and further, the first metal layer 24 is plated to form a local second metal. The protective coating layer 2 of the layer 25 can electrically connect the conductive contacts 321 to the contacts, and the other portions are insulated, and can pass the ASTM B117 5% salt spray test. Anti-corrosion requirements for rusting for more than 36 hours.

<Third Group Embodiment>

Please refer to FIG. 6. FIG. 6 is a schematic view showing a third group embodiment of the present invention for forming a protective coating layer on a substrate of a magnesium alloy by using the method of the present invention, which is applied to a rack plate of a server; A protective coating layer 2 is formed on the frame plate 41 of the servo frame 4. The material of the frame plate 41 is magnesium aluminum alloy (AZ31B), and the substrate 1 of magnesium aluminum alloy is formed by a molding method. The main technical requirement of the frame plate 41 of the servo frame 4 is that the surface heat conduction function can quickly derive the heat generated by the server, and the corrosion resistance requirement before the unpainting is required to pass the ASTM B117 5% salt spray test for more than 36 hours. Corrosion corrosion.

The protective coating layer 2 on the substrate 1 of the present embodiment is composed of the following: first, an oxidation protection layer 21 is formed on the substrate 1 by the micro-arc oxidation device 211 or other equipment, and the substrate 1 to which the oxidation protection layer 21 is attached is attached. After immersing in the ethanol solution of the polymer decane polymer 221, the surface modification layer 22 is dried by drying at 50 ° C, and then coated on the substrate 1 to which the surface modification layer 22 and the oxidation protection layer 21 are attached by spraying. The aqueous solution of the noble metal chelating agent 231 is dried at 35 ° C to form a nano precious metal chelate layer 23; then the substrate 1 to which the nano precious metal chelate layer 23, the surface modifying layer 22 and the oxidation protecting layer 21 are attached is immersed In the electroless plating bath 241, a first electroless plating reaction, such as electroless nickel plating or electroless copper plating in the present embodiment, followed by a first electroless plating reaction (or using electroplating) is used to thicken the electroless nickel plating. Or electroless copper plating to form the first metal layer 24.

In the embodiment of the present invention, the protective coating layer 2 of the first metal layer 24 is formed on the frame plate 41 of the servo frame 4 magnesium alloy material by the method for forming the protective coating layer on the surface of the magnesium alloy of the present invention. In addition to the adhesion of 5B (ASTM-3359), it can pass at least ASTM B117 5% salt spray test for more than 36 hours without rusting. Further, the frame plate 41 of magnesium-aluminum alloy has a metal outer layer. Has good thermal conductivity and meets the needs of use.

For other needs, the surface of the first metal layer 24 of the cladding layer 2 may be protected on the frame plate 41, and then coated with a coating layer 26 of inorganic enamel paint (not shown), which may be oxidized. The silica gel (SiO ₂ so-gel) is not limited.

<Fourth Group of Embodiments>

Referring to FIG. 7, FIG. 7 is a schematic view showing a fourth embodiment of the present invention for forming a protective coating on a substrate of a magnesium alloy by the method of the present invention, which is applied to a notebook computer case; The casing 51 of the computer 5 is formed with a patterned protective coating layer 2, and the material of the casing 51 is magnesium aluminum alloy (AZ91D), and the substrate 1 of magnesium-aluminum alloy is formed by a molding method. The main process requirement of the housing 51 of the computer 5 is that there is a pattern 511 on the housing 51, which is a pattern of metallic color texture in the paint layer, and the corrosion resistance requirement before unpainting is passed through ASTM B117 5% salt spray test 36. No rust or corrosion for more than one hour, other surfaces are metallic color texture or can be recoated Wear anti-fingerprint coatings.

The protective coating layer 2 on the substrate 1 of the present embodiment is first composed of an oxidation protective layer 21, a surface modifying layer 22, a nano precious metal chelate layer 23, and a first metal layer 24. The embodiment is not described here.

The substrate 1 (with the nano precious metal chelate layer 23, the surface modifying layer 22, and the oxidized protective layer 21 attached) coated with the first metal layer 24 is shielded in the pattern portion and placed in the plating tank 251. Electroplating (or electroless plating in the electroless plating bath 241) to form the second metal layer 25; removing the masking of the pattern portion, and spraying the organic coating on the surface of the first metal layer 24 of the shielding portion by the painting device 261 Thereafter, a coating layer 26 is formed; then, the coating layer 26 is engraved to remove the coating layer 26 of the pattern 511 by a laser engraving apparatus (not shown), and the portion of the coating layer 26 from which the pattern 511 is removed is exposed. The first metal layer 24 is formed on the portion where the first metal layer 24 is exposed, electroplated (plated in the plating bath 251 for electroplating), or electroless plating (electroless plating in the electroless plating bath 241) or brush plating, etc. Without limitation, a second second metal layer 25 is formed; for further appearance requirements, and further, the anti-fingerprint coating is re-sprayed onto the surface of the coating layer 26 and the second second metal layer 25.

In the present group of embodiments, a patterned protective coating layer 2 is formed on the casing 51 of the computer 5 by the method of forming a protective coating layer on the surface of the magnesium alloy of the present invention, except that it has 5B (ASTM-3359). In addition to the adhesion, at least the ASTM B117 5% salt spray test can be used for more than 36 hours without rusting, and further, the protective coating layer 2 of the second metal layer 25 formed on the first metal layer 24 can be It has a bright texture of chrome metal, a low-profile metal texture of metallized ceramic CrC, and can be tested by ASTM B117 5% salt spray for more than 36 hours without corrosion (this example can be at least 48 hours), in addition to the pattern Part 511 is painted with brightly colored organic paint and a gold second second metal layer 25, giving the pattern 511 a golden shiny color texture, or an anti-fingerprint coating.

<Fifth Group Embodiment>

The fifth group of embodiments of the present invention utilizes the method of the present invention to form a protective coating on a substrate of a magnesium alloy, which is applied to a steering wheel stereo sensor of an automobile, and constitutes a stereo sensor circuit on the steering wheel of the automobile, using a stereoscopic The sensor's circuit is connected to various control switches, such as directional lights, wipers, air conditioners, audio-visual devices or driving navigation recorders. This component is called 3D-MID (3D moulded interconnected device); In the embodiment, the patterned steering cover 2 is formed on the steering wheel assembly of the automobile. The material of the steering wheel assembly is magnesium alloy (AZ31), and the substrate 1 of magnesium aluminum alloy is formed by forging. The main process requirement for the steering wheel assembly is a circuit pattern with a stereo sensor on the steering wheel assembly. The corrosion resistance requirements before unpainting are to be rust-free by ASTM B117 5% salt spray test for more than 36 hours, part of the circuit pattern. And non-conducting circuit patterns are coated with protective coating for electrical insulation and aesthetic protection.

The protective coating layer 2 on the substrate 1 of the present embodiment is first composed of an oxidation protective layer 21, a surface modifying layer 22, and a nano precious metal chelate layer 23, wherein the nano precious metal chelate of the nano precious metal chelate layer 23 The mixture 231 solution is printed on the steering wheel assembly substrate 1 by a 3D printing machine to form a 3D circuit pattern having a nano precious metal chelate layer 23; the steering wheel assembly substrate 1 having the 3D circuit pattern is immersed in the chemical plating bath 241 The electroless plating reaction is performed to form electroless nickel plating, and then electroless copper plating is formed to form a first metal layer 24, wherein the first metal layer 24 is a metallized circuit pattern; and the metallization method can be used to use the Taiwan patent TW I361208 A method of forming a metal pattern on a substrate is disclosed, but is not limited thereto.

Similar to the fourth set of embodiments, the steering wheel assembly substrate 1 coated with the first metal layer 24 is placed in the plating bath 251 for electroplating (or electroless plating in the electroless plating bath 241) to form a second metal layer 25, The second metal layer 25 is increased in thickness on the first metal layer 24 to form a patterned circuit; for the insulation of the patterned circuit, the contact point of the patterned circuit to be connected to various control switches may be first shielded by the painting device 261. The second metal layer 25 and other desired portions are sprayed with an organic coating which is dried to form a coating layer 26.

Thereby, the lightweight and shock-resistant characteristics of the magnesium alloy can be utilized, and a patterned three-dimensional sensor circuit is formed on the steering wheel assembly of the magnesium alloy to form a molded interconnection component of the steering wheel, so that the wire connection of the automobile can be greatly reduced. Improve vehicle reliability and maintainability.

<Sixth Group Embodiment>

Referring to FIG. 8 , FIG. 8 is a schematic view showing a sixth set of embodiments of the present invention for forming a magnesium alloy body on a substrate of a magnesium alloy by using the method of the present invention; A protective coating layer 2 is formed on the body 61 of the camera 6, and the material of the body 61 is a magnesium-aluminum alloy (AZ31), and the substrate 1 of the magnesium-aluminum alloy is produced by a forging method. The main process requirement of the body 61 of the camera 6 is that the corrosion resistance requirements are not rusted by the ASTM B117 5% salt spray test for more than 36 hours before the coating is applied.

The protective coating layer 2 on the substrate 1 of the present embodiment is composed of the following: first, an oxidation protection layer 21 is formed on the substrate 1 by the micro-arc oxidation device 211 or other equipment, and the substrate 1 to which the oxidation protection layer 21 is attached is attached. After immersing in the ethanol solution of the polymer decane polymer 221, the surface modification layer 22 is dried by drying at 50 ° C, and then coated on the substrate 1 to which the surface modification layer 22 and the oxidation protection layer 21 are attached by spraying. The aqueous solution of the noble metal chelating agent 231 is dried at 35 ° C to form a nano precious metal chelate layer 23; then the substrate 1 to which the nano precious metal chelate layer 23, the surface modifying layer 22 and the oxidation protecting layer 21 are attached is immersed In the electroless plating bath 241, an electroless plating reaction, such as electroless copper plating and electroless nickel plating in the present embodiment, is performed to form the first metal layer 24; and the surface of the second metal layer 25 is sprayed with the inorganic enamel paint by the painting device 261. A layer of coating 26 is formed after drying.

In the present embodiment, the protective coating layer 2 of the first metal layer 24 formed on the fuselage 61 of the magnesium alloy material of the camera 6 is formed by the method of forming the protective coating layer on the surface of the magnesium alloy of the present invention. In addition to the adhesion of 5B (ASTM-3359), it can pass the ASTM B117 5% salt spray test for more than 36 hours without rusting.

<Seventh Group of Embodiments>

Referring to FIG. 9, FIG. 9 is a schematic view showing a seventh embodiment of the present invention, wherein a protective coating layer on a substrate for forming a magnesium alloy is applied to a circuit board by using the method of the present invention; The application of the present invention is disclosed in U.S. Patent No. 5,236,772. In the present embodiment, a protective conductive layer 71 is formed on the circuit board 7 of the magnesium-lithium alloy by a protective coating layer 2. The material of the circuit board 7 is LZ91, which is molded. The method is made of a substrate 1 of magnesium alloy. The main process requirement of the circuit board 7 is that there is a patterned conductive line 71 on the circuit board 7, and the circuit board 7 is required to pass the ASTM B117 5% salt spray test for more than 48 hours without rust corrosion.

The protective coating layer 2 on the substrate 1 of the present embodiment is first composed of an oxidation protective layer 21, a surface modifying layer 22, a nano precious metal chelate layer 23, and a first metal layer 24. The embodiment is not described here.

The aforementioned substrate 1 (with the nano precious metal chelate layer 23, the surface modifying layer 22, and the oxidized protective layer 21 attached) coated with the first metal layer 24 is shielded from the pattern portion of the conductive line 71, and placed. Electroplating is performed in the plating tank 251 to form the conductive line 71 of the second metal layer 25; and the shielding of the pattern portion is removed to form the patterned conductive line 71.

<Eighth Group Embodiment>

Referring to FIG. 10, FIG. 10 is a schematic view showing an eighth embodiment of the present invention for forming a protective coating on a substrate of a magnesium alloy by using the method of the present invention, which is applied to an LED heat sink fin; The LED heat-dissipating fins 8 made of magnesium alloy (AZ31) constitute a protective coating layer 2, and the LED heat-dissipating fins 8 are substrates 1 made of magnesium-aluminum alloy by extrusion molding. The main technical requirement of the LED heat sink fin 8 is that the surface heat conduction function can quickly derive the heat generated by the LED, and the corrosion resistance requirement before the unpainting is required to pass the ASTM B117 5% salt spray test for more than 36 hours without rust corrosion.

The protective coating layer 2 on the substrate 1 of the present embodiment is composed of the following: first, an oxidation protection layer 21 is formed on the substrate 1 by the micro-arc oxidation device 211 or other equipment, and the substrate 1 to which the oxidation protection layer 21 is attached is attached. After immersing in the ethanol solution of the polymer decane polymer 221, the surface modification layer 22 is dried by drying at 50 ° C, and then coated on the substrate 1 to which the surface modification layer 22 and the oxidation protection layer 21 are attached by spraying. The aqueous solution of the noble metal chelating agent 231 is dried at 35 ° C to form a nano precious metal chelate layer 23; then the substrate 1 to which the nano precious metal chelate layer 23, the surface modifying layer 22 and the oxidation protecting layer 21 are attached is immersed In the electroless plating bath 241, a first electroless plating reaction, such as electroless nickel plating or electroless copper plating in the present embodiment, followed by a first electroless plating reaction (or using electroplating) is used to thicken the electroless nickel plating. Or electroless copper plating to form the first metal layer 24.

In the embodiment of the present invention, the protective coating layer 2 of the first metal layer 24 is formed on the LED heat dissipation fin 8 of the magnesium alloy material by using the method for forming the protective coating layer on the surface of the magnesium alloy of the present invention, except In addition to the adhesion of 5B (ASTM-3359), it can pass the ASTM B117 5% salt spray test for at least 24 hours without rust. Further, the aluminum alloy aluminum foil fins 8 have a metal outer layer and have good The thermal conductivity of the product meets the needs of use.

The above is intended to be illustrative only and not limiting. Any equivalent modifications or alterations to the spirit and scope of the invention are intended to be included in the scope of the appended claims.

1‧‧‧Substrate

2‧‧‧protective coating

21‧‧‧Oxidation protective layer

211‧‧‧Micro-arc oxidation equipment

22‧‧‧ Surface modification layer

221‧‧‧ polymer silane polymer

23‧‧‧Nano precious metal chelate layer

231‧‧‧Nano precious metal chelating agent

24‧‧‧First metal layer

241‧‧‧Chemical plating bath

25‧‧‧Second metal layer

251‧‧‧ plating bath

26‧‧‧ paint layer

261‧‧‧painting equipment

Claims (16)

A method for forming a protective coating on a surface of a magnesium alloy, comprising the steps of: providing a substrate selected from one or a combination of magnesium, magnesium aluminum alloy, magnesium lithium alloy or magnesium aluminum zinc alloy; Forming an oxidized protective layer formed of crystalline porous ceramic; coating a nano-precious metal chelating layer on the oxidized protective layer, the nano-precious metal chelating layer is sprayed, dipped, printed One of the methods is coated with a nano precious metal chelating agent solution, which is formed by drying; wherein the nano precious metal chelating agent solution is an aqueous solution or a solvent solution of a nano precious metal chelating agent; the nano precious metal chelating agent is gold a noble metal particle of (Au), silver (Ag), palladium (Pd), platinum (Pt) or ruthenium (Ru) is attached to a polymer chelating agent, and the nano precious metal chelating agent has metal catalytic activity; The polymer chelating agent of the nano precious metal chelating agent is: A (polymer of polymer monomer (P) and N-isopropyl acrylamide monomer (Poly (P-Co-NIPAAmb))), B (Polymer monomer (P) and hydroxypropyl cellulose copolymer (Poly (P-hyd Roxypropylcellulose))), C (Poly(P-poly(vinylcaprolactame)), D (polymeric monomer (P) and polyvinyl) One or a combination of a poly(P-poly(vinyl methyl ether)); a first metal layer formed on the nano precious metal chelate layer, the first metal layer being electrolessly plated A nickel metal layer, a copper metal layer, a silver metal layer, a tin metal layer, a palladium metal layer, a gold metal layer or a plurality of layers formed thereof. A method for forming a protective coating layer on a surface of a magnesium alloy according to claim 1, wherein the oxidized protective layer is formed by one of an anodizing method, a micro-arc oxidation method or a plasma processing method, and the composition thereof It consists of one or a combination of the following groups: (1) one of magnesium oxide, magnesium hydroxide, aluminum oxide, and aluminum hydroxide or a combination thereof, (2) one of aluminum phosphate, magnesium phosphate, calcium phosphate or Combination, (3) aluminum borate, one or a combination of magnesium borate, (4) one or a combination of aluminum citrate, magnesium citrate, (5) magnesium aluminate, magnesium tungstate, magnesium vanadate, metavanadic acid One of magnesium or magnesium sulfate or a combination thereof. The method for forming a protective coating layer on the surface of the magnesium alloy according to the first aspect of the patent application, further coating a surface modifying layer on the oxidized protective layer, and overlying the surface modifying layer a nano precious metal chelating layer; wherein the surface modifying layer is coated with a polymer decane polymer obtained by polymerizing a polymer having a decyl group and a monomer, and polymerizing the polymer decane The system is selected from the group consisting of 3-aminopropyltriethoxysilane (APTES), vinyltrimethoxysilane (VTMS), 3-aminopropyltrimethoxydecane. (3-Aminopropyltrimethoxysilane, APTMS), 4-Aminobutyltrirthoxysilane (ABTS), N-(β-aminoethyl)-γ-aminopropylmethyldimethoxydecane (N -(2-Aminorthyl)-3-aminoproPylmethyldi-methoxysilane, NAAPMDMS), 3-Aminopropylmethyldiethoxysilane (APMDES), 3-aminopropyldiisopropylethoxypropane ( 3-Aminopropyldiisopropylethoxysilane, APDIPES), 3-(methacrylofluorene) ) Trimethoxy Silane (3- (Methacryloyloxy) propyltrimethoxysilane, MPS) solution of one or a combination thereof. The method for forming a protective coating layer on a surface of a magnesium alloy according to claim 1, wherein the polymer chelating agent of the nano precious metal chelating agent has temperature denaturation characteristics; wherein the temperature denaturation property is set The temperature ratio of the nano precious metal chelating agent solution is hydrophilic, and the polymer chelating agent is converted to hydrophobic when the temperature is higher or lower than the temperature range of the nano precious metal chelating agent solution. A method for forming a protective coating layer on a surface of a magnesium alloy as described in claim 1, wherein the polymer monomer (P) may be selected from the following monomer molecules: styrene (P1) (Styrene), acrylic acid ( P2) (Acrylic acid), Methacrylic acid, Methyl acrylate or Methyl methacrylate monomer, Ethylene (P6) One of a monomer, a propylene (P7) (Propylene) monomer, a vinyl chloride (P8) (Vinyl chloride) monomer, or a combination thereof. The method for forming a protective coating layer on the surface of the magnesium alloy according to the first aspect of the patent application, further forming a coating layer by spraying, dipping or printing on the first metal layer, the coating layer The layer is selected from the group consisting of an organic polymer coating, an inorganic enamel coating, an organic and inorganic composite coating, an anti-fingerprint coating, or a combination thereof; wherein, the anti-fingerprint coating is selected from magnesium fluoride aluminum oxide (MgAlO _x F _y ), Fluorosilicone, carbon fluoride nitrogen (C _X N _(1-X) F _Y ), fluorinated amorphous germanium dioxide (SiO _X F _Y ), fluorinated amorphous alumina (AlO _x F _y ), poly a coating composed of polytetrafluoroethylene, cloflucarban, metal oxynitride (MeON) or one of the products 3M ^® ECC-4000, KINGFIRST ^® UM-6211, or a combination thereof; wherein X, Y are a number; wherein the metal Me of the metal oxynitride is one or a combination of titanium, aluminum, lanthanum, chromium, and zirconium. The method for forming a protective coating layer on the surface of the magnesium alloy according to the first aspect of the patent application, further forming a second metal layer on the first metal layer, wherein the second metal layer is an electroless plating method or a plating method. Or a nickel metal layer, a copper metal layer, a silver metal layer, a tin metal layer, a gold metal layer, a base metal layer, a metallized ceramic layer formed by one or a combination thereof, or a plurality of layers thereof; The metallized ceramic layer is formed by a eutectic stack of a metal and a non-metal co-formed amorphous phase, wherein the metal is one of molybdenum, chromium, vanadium, nickel or a combination thereof, and the non-metal nitrogen, oxygen or One or a combination of carbon. A method for forming a protective coating layer on a surface of a magnesium alloy according to claim 7 of the patent application, further forming a coating layer by spraying, dipping or printing on the second metal layer, the coating layer The layer is selected from one of organic polymer coatings, inorganic enamel coatings, anti-fingerprint coatings or combinations thereof; wherein the anti-fingerprint coating is selected from the group consisting of magnesium fluoride oxide (MgAlO _x F _y ), fluorosilicone, fluorine Carbonitride (C _X N _(1-X) F _Y ), fluorinated amorphous cerium oxide (SiO _X F _Y ), fluorinated amorphous alumina (AlO _x F _y ), polytetrafluoroethylene a coating comprising one or a combination of cloflucarban, metal oxide (MeON) or commercial 3M ^® ECC-4000, KINGFIRST ^® UM-6211; wherein X, Y are numbers; wherein, metal nitrogen The metal Me of the oxide is one or a combination of titanium, aluminum, lanthanum, chromium and zirconium. A protective coating layer is coated on a substrate, and the protective coating layer comprises, in order from the bottom to the surface, an oxidation protective layer, a nano precious metal chelate layer and a first metal layer; wherein the substrate Is one selected from the group consisting of magnesium, magnesium aluminum alloy, magnesium lithium alloy or magnesium aluminum zinc alloy or a combination thereof; wherein the oxidation protective layer is composed of crystalline porous ceramic; Wherein, the nano precious metal chelate layer is formed by a nano precious metal chelating agent, such as gold (Au), silver (Ag), palladium (Pd), platinum (Pt) or ruthenium (Ru). The noble metal particles are attached to a polymer chelating agent; wherein the polymer chelating agent of the nano precious metal chelating agent is: A (polymer monomer (P) and N-isopropyl acrylamide monomer) Copolymer (Poly(P-Co-NIPAAmb)), B (Poly(P-hydroxypropylcellulose)), C (polymer monomer) P) Copolymer with polyvinyl caprolactam (Poly(P-poly(vinylcaprolactame))), D (copolymer of polymer monomer (P) and polyvinyl methyl ether (Poly(P-poly( One or a combination of vinyl methyl ether))); wherein the first metal layer is a nickel metal layer, a copper metal layer, a silver metal layer, a tin metal layer, a palladium metal layer, or a gold metal layer formed by electroless plating One or multiple layers of each other. A protective covering layer is coated on a substrate, and the protective covering layer comprises, in order from the bottom to the surface, an oxidation protective layer, a surface modifying layer, a nano precious metal chelate layer and a first metal a layer; wherein the substrate is one selected from the group consisting of magnesium, magnesium aluminum alloy, magnesium lithium alloy or magnesium aluminum zinc alloy or a combination thereof; wherein the oxidation protection layer is composed of crystalline porous ceramic; wherein the surface modification The layer is formed by a polymer decane polymer which is obtained by polymerizing a polymer having a decyl group and a monomer; wherein the nano precious metal chelating layer is composed of a nano precious metal chelating agent Forming, the nano precious metal chelating agent is composed of a noble metal particle of gold (Au), silver (Ag), palladium (Pd), platinum (Pt) or ruthenium (Ru) attached to a polymer chelating agent; wherein The polymer chelating agent of the nano precious metal chelating agent is: A (polymer of polymer monomer (P) and N-isopropyl acrylamide monomer (Poly (P-Co-NIPAAmb))), B (Polymer monomer (P) and hydroxypropyl cellulose (Poly (P-hydroxypropyl))), C (polymer monomer (P) Copolymer with polyvinyl caprolactam (Poly(P-poly(vinylcaprolactame))), D (copolymer of polymer monomer (P) and polyvinyl methyl ether (Poly(P-poly(vinyl methyl) Either or a combination thereof; wherein the first metal layer is one of a nickel metal layer, a copper metal layer, a silver metal layer, a tin metal layer, a palladium metal layer, a gold metal layer formed by electroless plating or It consists of multiple layers of each other. The protective coating layer according to claim 10, wherein the polymer decane polymer is selected from the group consisting of 3-aminopropyltriethoxysilane (APTES), vinyl Trimethoxypropyltrimethoxysilane (VTMS), 3-Aminopropyltrimethoxysilane (APTMS), 4-Aminobutyltrirthoxysilane (ABTS), N-(β- Aminoethyl)-γ-aminopropylmethyldimethoxysilane (N-(2-Aminorthyl)-3-aminopropylmethyldi-methoxysilane, NAAPMDMS), 3-aminopropylmethyldiethoxydecane (3- Aminopropylmethyldiethoxysilane, APMDES), 3-Aminopropyldiisopropylethoxysilane (APDIPES), 3-(Methacryloyloxy)propyltrimethoxysilane, MPS a solution of one or a combination thereof. The protective coating layer according to claim 9 or 10, wherein the oxidized protective layer is a crystalline porous ceramic formed by one or a combination of the following groups: (1) magnesium oxide, hydrogen hydroxide One or a combination of magnesium, aluminum oxide, and aluminum hydroxide, (2) one or a combination of aluminum phosphate, magnesium phosphate, calcium phosphate, (3) one or a combination of aluminum borate, magnesium borate, (4) 矽One or a combination of aluminum acid, magnesium citrate or (5) magnesium aluminate, magnesium tungstate, magnesium vanadate, magnesium metavanadate, magnesium sulfate or a combination thereof. The protective coating layer according to claim 9 or 10, wherein the polymer monomer (P) is selected from the following monomer molecules: styrene (P1) (Styrene), acrylic acid (P2) (Acrylic acid). ), Methacrylic acid, Methyl acrylate or Methyl methacrylate monomer, ethylene (P6) (Ethylene) monomer, propylene (P7) (Propylene) monomer, one of vinyl chloride (P8) (Vinyl chloride) monomers or a combination thereof. The protective coating layer according to claim 9 or 10, further comprising a coating layer covering all or a part of the first metal layer; the coating layer is selected from organic One or a combination of a polymer coating, an inorganic enamel coating, an organic and inorganic composite coating, an anti-fingerprint coating, wherein the anti-fingerprint coating is selected from the group consisting of magnesium fluoride aluminum oxide (MgAlO _x F _y ), fluorosilicone, fluorine Carbonitride (C _X N _(1-X) F _Y ), fluorinated amorphous cerium oxide (SiO _X F _Y ), fluorinated amorphous alumina (AlO _x F _y ), polytetrafluoroethylene a coating comprising one or a combination of cloflucarban, metal oxynitride (MeON) or commercial 3M ^® ECC-4000, KINGFIRST ^® UM-6211; wherein X, Y are numbers; wherein, metal nitrogen The metal Me of the oxide is one or a combination of titanium, aluminum, lanthanum, chromium and zirconium. The protective coating layer of claim 9 or 10, further comprising a second metal layer covering all or a part of the first metal layer; the second metal The layer is a nickel metal layer, a copper metal layer, a silver metal layer, a tin metal layer, a gold metal layer, a base metal layer, a metallized ceramic layer formed by one or a combination of an electroless plating method, an electroplating method, or an evaporation method. a multilayer formed by or in combination with each other; wherein the metallized ceramic layer is formed by a eutectic stack of a metal and a non-metal co-formed amorphous phase, wherein the metal is one of molybdenum, chromium, vanadium, nickel or Combination, non-metallic one of nitrogen, oxygen or carbon or a combination thereof. The protective coating layer of claim 15, further comprising a coating layer covering all or a part of the second metal layer, the coating layer being selected from the group consisting of organic polymer coatings , one or a combination of inorganic enamel coatings, organic and inorganic composite coatings, anti-fingerprint coatings, wherein the anti-fingerprint coating is selected from the group consisting of magnesium fluoride aluminum oxide (MgAlO _x F _y ), fluorosilicone, carbon fluoride nitrogen (C _X N _(1-X) F _Y ), fluorinated amorphous cerium oxide (SiO _X F _Y ), fluorinated amorphous alumina (AlO _x F _y ), polytetrafluoroethylene, chlorofluoro a coating comprising cloflucarban, metal oxynitride (MeON) or one of the commercial products 3M ^® ECC-4000, KINGFIRST ^® UM-6211, or a combination thereof; wherein X, Y are numbers; wherein, metal oxynitride The metal Me is one or a combination of titanium, aluminum, lanthanum, chromium, and zirconium.