A method for processing a plastic part and a plastic part

Abstract

The application discloses a processing method of plastic parts and the plastic parts, and relates to the technical field of plastic materials. The application creatively takes a water electroplating layer as a bottom layer and a PVD layer as a surface layer to form a composite plating layer structure of plastic-water electroplating-PVD, and develops an environmental protection type passivation liquid and an activation liquid formula suitable for copper and nickel metal surfaces to retain the original metal luster of the parts after water electroplating and the bonding force requirement of the PVD plating layer. The processing method provided by the application can make the products have the mirror surface bright metal texture of water electroplating and the high hardness, high wear resistance, colorization and excellent corrosion resistance of the PVD plating layer, and the whole process is more environmental protection.

Description

Technical Field

[0001] This invention relates to the field of surface coating technology, and more specifically, to a processing method for plastic parts and plastic parts thereof. Background Technology

[0002] Plastic parts are widely used in consumer electronics, automobiles, and home décor due to their advantages such as light weight, low cost, and ease of molding. To achieve a metallic finish, enhance aesthetics, and improve durability, surface metallization is typically required. Currently, the two main surface metallization technologies are:

[0003] (1) Electroplating

[0004] Electroplating technology is mature and can achieve a mirror-like high gloss and a strong metallic effect, with a thick coating and good corrosion resistance. However, traditional electroplating processes have serious environmental pollution problems (using cyanide, strong acids and alkalis), complex processes, and high wastewater treatment costs. Moreover, electroplated coatings have limited color options (mainly chromium, nickel, gold, gunmetal, etc.) and are not wear-resistant and easily scratched.

[0005] (2) Vacuum plating (PVD)

[0006] Vacuum plating (PVD) offers advantages such as being environmentally friendly and pollution-free, producing a wide variety of colors (e.g., IP black, IP blue, rose gold), high hardness, and resistance to wear and scratches. However, when directly plating onto plastic substrates, the metallic effect is not strong, making it difficult to achieve the mirror finish of electroplating; the coating is also relatively thin, and its corrosion resistance (e.g., salt spray test) is generally inferior to that of electroplating.

[0007] Therefore, there is an urgent need to develop new surface treatment technologies that enable products to have a mirror-like, bright metallic texture while also possessing advantages such as high hardness, high wear resistance, multi-colorability, and excellent corrosion resistance, while making the entire process more environmentally friendly.

[0008] In view of this, the present invention is proposed. Summary of the Invention

[0009] The purpose of this invention is to provide a processing method for plastic parts and plastic parts in general, which aims to produce plastic products that combine the mirror-like metallic texture of electroplating with the high hardness, high wear resistance, multi-colorability and excellent corrosion resistance of PVD coating.

[0010] This invention is implemented as follows:

[0011] In a first aspect, the present invention provides a method for processing plastic parts, comprising:

[0012] Pretreatment: Plastic materials are used as raw materials for molding, and then a conductive chemical plating layer is formed on the surface;

[0013] Electroplating deposition: Electroplating is performed on pretreated materials to form an underlying electroplating layer;

[0014] Intermediate treatment: The material with the underlying electroplated layer is subjected to acid activation and passivation treatment, followed by PVD pre-activation treatment; the passivation solution used in the passivation treatment consists of: main film-forming agent greater than or equal to 0.1 g / L, oxidant 20 g / L-25 g / L, organic corrosion inhibitor 1 g / L-8 g / L, silane coupling agent 5 g / L-10 g / L, and first pH value adjuster 50 g / L-90 g / L; the activation solution used in the PVD pre-activation treatment consists of: sulfonic acid organic acid 50 g / L-150 g / L, oxidant 10 g / L-50 g / L, complexing agent 5 g / L-30 g / L, nonionic surfactant 0.1 g / L-5.0 g / L, corrosion inhibitor 0.01 g / L-2.00 g / L, and second pH value adjuster 1 g / L-10 g / L;

[0015] PVD coating deposition: Depositing a PVD functional decorative layer on the surface of a material that has undergone intermediate treatment;

[0016] Post-processing involves forming a protective layer on the material with a PVD-functional decorative layer.

[0017] In an optional implementation, the passivation process has at least one of the following features A1-H1:

[0018] Feature A1: The main film-forming agent is selected from at least one of 8-hydroxyquinoline, an azo derivative of 8-hydroxyquinoline, and 2-methylimidazole;

[0019] Feature B1: The oxidant is selected from at least one of sodium molybdate, potassium molybdate, and zinc molybdate;

[0020] Feature C1: The organic corrosion inhibitor is selected from at least one of 1-phenyl-5-mercaptotetrazole and 5-mercapto-1-methyltetrazole;

[0021] Feature D1: The silane coupling agent is selected from at least one of γ-aminopropyltriethoxysilane and γ-glycidoxypropyltrimethoxysilane;

[0022] Feature E1: The first pH adjuster is selected from at least one of sodium citrate and potassium citrate;

[0023] Feature F1: The solvent used to prepare the passivation solution is deionized water;

[0024] Feature G1: The passivation solution is composed of the following: main film-forming agent 0.4g / L-0.6g / L, oxidant 21g / L-23g / L, organic corrosion inhibitor 3g / L-6g / L, silane coupling agent 6g / L-9g / L, first pH adjuster 65g / L-75g / L, and the balance is deionized water;

[0025] Feature H1: The material is placed in a passivation solution and passivated for 30-60 seconds at 20℃-30℃.

[0026] In an optional implementation, the pre-PVD activation treatment has at least one of the following features A2-I2:

[0027] Feature A2: The sulfonic acid organic acid is selected from at least one of aminosulfonic acid and methanesulfonic acid;

[0028] Feature B2: The oxidant is selected from at least one of hydrogen peroxide solution and sodium percarbonate; the mass fraction of the hydrogen peroxide solution is 20%-40%;

[0029] Feature C2: The complexing agent is selected from at least one of citric acid and ethylenediaminetetraacetic acid;

[0030] Feature D2: The nonionic surfactant is selected from at least one of fatty alcohol polyoxyethylene ether and alkylphenol polyoxyethylene ether;

[0031] Feature E2: When the chemical plating layer formed during the pretreatment process is a copper plating layer, the corrosion inhibitor is selected from at least one of benzotriazole and 5-methylbenzotriazole; when the chemical plating layer formed during the pretreatment process is a nickel plating layer, the corrosion inhibitor is selected from at least one of thiourea and 2,4-dithiobiurea.

[0032] Feature F2: The second pH adjuster is selected from at least one of boric acid and sodium tetraborate;

[0033] Feature G2: The solvent used to prepare the activation solution is deionized water;

[0034] Characteristic H2: The composition of the activation solution used in the PVD pre-activation treatment is as follows: sulfonic acid organic acid 90g / L-110g / L, oxidant 25g / L-35g / L, complexing agent 13g / L-18g / L, nonionic surfactant 0.5g / L-1.5g / L, corrosion inhibitor 0.3g / L-0.8g / L, second pH adjuster 3g / L-7g / L, and the balance is deionized water;

[0035] Feature I2: Place the material in an activation solution and activate it for 30-60 seconds at 20℃-30℃.

[0036] In an optional embodiment, the intermediate processing includes: acid activation and passivation of the material with the underlying electroplated layer, followed by baking, degreasing, and cleaning, and then PVD pre-activation treatment, followed by cleaning and baking.

[0037] The acid solution used in the acid activation process is a sulfuric acid solution with a mass fraction of 8%-12%.

[0038] In an optional embodiment, the electroplating deposition process includes: sequentially forming a copper layer, a semi-bright nickel layer, a bright nickel layer, and a microporous nickel layer;

[0039] The copper layer has a thickness of 20μm-30μm, the semi-bright nickel layer has a thickness of 12μm-18μm, the bright nickel layer has a thickness of 6μm-10μm, and the microporous nickel layer has a thickness of 1μm-3μm.

[0040] In an optional embodiment, when preparing the copper layer, the temperature of the electroplating solution is controlled at 22°C-26°C, and the electroplating time is 2200s-2600s.

[0041] And / or, when preparing a semi-bright nickel layer, the temperature of the electroplating solution is controlled at 50℃-60℃ and the electroplating time is 1100s-1300s;

[0042] And / or, when preparing the bright nickel layer, the temperature of the electroplating solution is controlled at 50℃-60℃ and the electroplating time is 740s-860s;

[0043] And / or, when preparing a microporous nickel layer, the temperature of the electroplating solution is controlled at 50℃-60℃ and the electroplating time is 210s-270s;

[0044] And / or, control the current density during the electroplating process to be 2 A / dm³. 2 -5A / dm 2 .

[0045] In an optional embodiment, the pretreatment process includes: after injection molding the plastic material, sequentially performing degreasing, roughening, neutralization, palladium activation, degumming, and chemical plating.

[0046] In an optional implementation, the PVD coating deposition process has at least one of the following characteristics A3-E3:

[0047] Feature A3: Control the thickness of the PVD functional decorative layer to be 0.2μm-1.5μm;

[0048] Feature B3: The PVD process used is selected from at least one of multi-arc ion plating and magnetron sputtering;

[0049] Feature C3: The coating material used is selected from at least one of zirconium target, titanium target and chromium target;

[0050] Feature D3: The reactant gas is selected from at least one of nitrogen, acetylene, and oxygen;

[0051] Feature E3: The intermediate-processed material is loaded into the PVD vacuum chamber, and a PVD functional decorative layer is deposited, with the vacuum level controlled at 2.0 × 10⁻⁶. -3 Pa-5.0×10 -3 Pa, arc current of 60A-120A, bias voltage of -100V to -300V, deposition temperature ≤110°C.

[0052] In an optional embodiment, the process of forming the protective layer includes: coating a protective varnish onto a material having a PVD functional decorative layer, followed by curing; the protective varnish is selected from at least one of polyurethane acrylate, silicone resin, nano silica, and hindered amine light stabilizer;

[0053] And / or, the thickness of the protective layer is 8μm-12μm.

[0054] Secondly, the present invention provides a plastic part, which is prepared by the plastic part processing method of any of the foregoing embodiments.

[0055] This invention offers the following advantages: It creatively uses an electroplated layer as the base layer and a PVD layer as the top layer, forming a composite coating structure of "plastic-electroplating-PVD." By developing environmentally friendly passivation and activation solutions suitable for copper and nickel metal surfaces, it preserves the original metallic luster of the electroplated parts and the required adhesion to the PVD coating. The processing method provided by this invention allows products to possess both the mirror-like metallic finish of electroplating and the high hardness, high wear resistance, multi-colorability, and excellent corrosion resistance of PVD coatings, while the entire process is more environmentally friendly. Attached Figure Description

[0056] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0057] Figure 1 This is a partial flowchart of the processing method provided in an embodiment of the present invention;

[0058] Figure 2 This is a flowchart of the PVD electroplating portion of the processing method provided in the embodiments of the present invention;

[0059] Figure 3 This is a schematic diagram of the coating structure of the product prepared according to an embodiment of the present invention. Detailed Implementation

[0060] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. Where specific conditions are not specified in the embodiments, conventional conditions or conditions recommended by the manufacturer shall apply. Reagents or instruments whose manufacturers are not specified are all conventional products that can be purchased commercially.

[0061] This invention is a composite processing method that combines traditional electroplating with physical vapor deposition (PVD). By developing environmentally friendly passivation and activation solution formulations suitable for copper and nickel metal surfaces, the passivation solution preserves the original metallic luster of the electroplated parts, while the activation solution ensures adhesion to the PVD coating. The processing method provided by this invention can produce plastic products with excellent overall performance.

[0062] This invention provides a method for processing plastic parts, the steps of which are as follows:

[0063] S1, Preprocessing

[0064] Plastic materials suitable for electroplating are selected as raw materials. After molding, a conductive chemical plating layer (usually chemical copper or chemical nickel plating) is formed on the surface through conventional chemical pretreatment, providing a conductive basis for subsequent electroplating.

[0065] The specific type of plastic material is not limited, such as ABS (acrylonitrile-butadiene-styrene copolymer), PC / ABS (polycarbonate / ABS alloy), PP (polypropylene), PA (polyamide (commonly known as nylon)), etc., but not limited to these.

[0066] The molding method can employ traditional injection molding, with strict control over the injection process to avoid defects such as internal stress and air bubbles. For example... Figure 1 As shown, after injection molding, the product is loaded onto the machine and undergoes degreasing, roughening, neutralization, palladium activation, degumming, and electroless plating in sequence. Electroless plating can be either electroless nickel plating (i.e., chemical nickel plating) or electroless copper plating.

[0067] Specifically, degreasing can be achieved using alkaline degreasing agents. Through soaking and ultrasonic assistance, the oil stains are removed through saponification and emulsification. There are no restrictions on the type of alkaline degreasing agent.

[0068] Specifically, the purpose of roughening is to improve the adhesion between the coating and the plastic substrate. This can be achieved by micro-etching the plastic surface through the corrosive action of strong oxidizing acids (such as a mixture of chromic acid and sulfuric acid).

[0069] Specifically, neutralization can completely remove hexavalent chromium ions remaining in the micropores and surface of plastic parts. Reducing solutions (such as sodium bisulfite, ammonia, etc.) are used to reduce the highly oxidizing hexavalent chromium to the less toxic trivalent chromium, which is then dissolved and washed away.

[0070] Specifically, palladium activation can adsorb a layer of catalytically active noble metal particles onto the plastic surface, serving as a "seed" or "catalyst" for electroless plating. The specific operation of palladium activation involves immersing the roughened and neutralized plastic parts in a colloidal palladium activation solution containing stannous chloride and palladium chloride.

[0071] Specifically, degumming removes the tin ion shell surrounding the palladium nucleus, fully exposing the catalytically active palladium nucleus. The degumming process involves immersing the nucleus in an acidic degumming solution (such as dilute sulfuric acid or fluoroboric acid) to dissolve the outer tin compound, revealing the pure palladium atoms.

[0072] Specifically, electroless plating involves depositing a uniform, dense, and conductive metal layer onto an activated plastic surface through an autocatalytic redox reaction. The workpiece is immersed in an electroless plating solution containing metal ions (such as nickel or copper ions) and a reducing agent (such as sodium hypophosphite). On the surface of the catalytically active palladium nucleus, the reducing agent reduces the metal ions in the solution to metal atoms, which are then deposited.

[0073] Pre-plating with nickel can be selectively performed after electroless nickel plating. Pre-plating involves electroplating a dense, well-adhesive, low-stress "base" nickel layer on top of the electroless plating layer, providing a solid foundation for all subsequent electroplating processes. Pre-plating is essentially an electroplating process, but the plating solution and parameters used differ significantly from those used in subsequent conventional nickel plating, aiming to gently and stably establish the initial plating layer.

[0074] S2, Electroplating layer deposition

[0075] Electroplating is performed on the pretreated material to form the underlying electroplated layer.

[0076] In some embodiments, such as Figure 1 and Figure 3 As shown, the electroplating deposition process includes the sequential formation of a copper layer, a semi-bright nickel layer, a bright nickel layer, and a microporous nickel layer. The thickness of the copper layer is 20μm-30μm, such as 20μm, 23μm, 25μm, 28μm, 30μm, etc.; the thickness of the semi-bright nickel layer is 12μm-18μm, such as 12μm, 13μm, 14μm, 15μm, 16μm, 17μm, 18μm, etc.; the thickness of the bright nickel layer is 6μm-10μm, such as 6μm, 7μm, 8μm, 9μm, 10μm, etc.; and the thickness of the microporous nickel layer is 1μm-3μm, such as 1μm, 2μm, 3μm, etc.

[0077] In some embodiments, when preparing the copper layer, the temperature of the electroplating solution is controlled to be 22℃-26℃, such as 22℃, 23℃, 24℃, 25℃, 26℃, etc.; the electroplating time is 2200s-2600s, such as 2200s, 2300s, 2400s, 2500s, 2600s, etc.

[0078] In some embodiments, when preparing a semi-bright nickel layer, the temperature of the electroplating solution is controlled at 50℃-60℃, such as 50℃, 53℃, 55℃, 58℃, 60℃, etc.; the electroplating time is 1100s-1300s, such as 1100s, 1150s, 1200s, 1250s, 1300s, etc.

[0079] In some embodiments, when preparing the bright nickel layer, the temperature of the electroplating solution is controlled at 50℃-60℃, such as 50℃, 53℃, 55℃, 58℃, 60℃, etc.; the electroplating time is 740s-860s, such as 740s, 760s, 780s, 800s, 820s, 840s, 860s, etc.

[0080] In some embodiments, when preparing the microporous nickel layer, the temperature of the electroplating solution is controlled at 50℃-60℃, such as 50℃, 53℃, 55℃, 58℃, 60℃, etc.; the electroplating time is 210s-270s, such as 210s, 220s, 230s, 240s, 250s, 260s, 270s, etc.

[0081] Furthermore, the current density during the electroplating process is controlled to be 2 A / dm³. 2 -5A / dm 2 For example, it can be 2A / dm 2 3A / dm 2 4A / dm 2 5A / dm 2 wait.

[0082] S3, Intermediate Processing

[0083] After electroplating, the parts are thoroughly cleaned to remove any residual electroplating solution. Then, they undergo acid activation and passivation treatment, followed by complete drying to obtain parts that retain their original metallic color. Subsequently, a PVD pre-activation treatment is performed to activate the surface of the electroplated layer, remove microscopic contaminants and oxides, and enhance the adhesion between the PVD coating and the electroplated layer.

[0084] In actual operation, please refer to Figure 1 and Figure 2The intermediate processing includes: acid activation and passivation of the material with the underlying electroplated layer, followed by baking, and after passing the inspection, degreasing, cleaning, and activation (activation treatment before PVD), followed by cleaning (which can be done twice) and baking.

[0085] In some embodiments, acid activation can be performed using a weak acid solution. The acid solution used in the acid activation process is a sulfuric acid solution with a mass fraction of 8%-12%, but is not limited to this.

[0086] Furthermore, the passivation solution used in the passivation treatment comprises: a main film-forming agent greater than or equal to 0.1 g / L, an oxidant of 20 g / L-25 g / L, an organic corrosion inhibitor of 1 g / L-8 g / L, a silane coupling agent of 5 g / L-10 g / L, and a first pH adjuster of 50 g / L-90 g / L. Preferably, the passivation solution comprises: a main film-forming agent of 0.4 g / L-0.6 g / L, an oxidant of 21 g / L-23 g / L, an organic corrosion inhibitor of 3 g / L-6 g / L, a silane coupling agent of 6 g / L-9 g / L, a first pH adjuster of 65 g / L-75 g / L, with the balance being deionized water. By optimizing the composition of the passivation solution, the passivation effect is improved, resulting in parts that completely retain their metallic color.

[0087] Specifically, the content of the main film-forming agent can be from 0.1 g / L to saturation, such as 0.1 g / L, 0.2 g / L, 0.3 g / L, 0.4 g / L, 0.5 g / L, 0.6 g / L, 0.7 g / L, 0.8 g / L, 0.9 g / L, 1.0 g / L, etc. The content of the oxidant can be 20 g / L, 21 g / L, 22 g / L, 23 g / L, 24 g / L, 25 g / L, etc. The content of the organic corrosion inhibitor can be 1 g / L, 2 g / L, 3 g / L, 4 g / L, 5 g / L, 6 g / L, 7 g / L, 8 g / L, etc. The content of the silane coupling agent can be 5 g / L, 6 g / L, 7 g / L, 8 g / L, 9 g / L, 10 g / L, etc. The concentration of the first pH adjuster can be 50 g / L, 55 g / L, 60 g / L, 65 g / L, 70 g / L, 75 g / L, 80 g / L, 85 g / L, 90 g / L, etc.

[0088] In some embodiments, the primary film-forming agent is selected from at least one of 8-hydroxyquinoline, an azo derivative of 8-hydroxyquinoline, and 2-methylimidazole. The primary film-forming agent can be any one or more of the above, forming a dense film layer through self-assembly. The oxidant is selected from at least one of sodium molybdate, potassium molybdate, and zinc molybdate. The oxidant can be any one or more of the above, promoting passivation of the metal surface. The organic corrosion inhibitor is selected from at least one of 1-phenyl-5-mercaptotetrazole and 5-mercapto-1-methyltetrazole. The organic corrosion inhibitor can be any one or more of the above, inhibiting corrosion and enhancing film uniformity. The silane coupling agent is selected from at least one of γ-aminopropyltriethoxysilane and γ-glycidoxypropyltrimethoxysilane. The silane coupling agent can be any one or more of the above, improving film adhesion and bonding strength. The first pH adjuster is selected from at least one of sodium citrate and potassium citrate. The first pH adjuster can be any one or more of the above. By adding a specific type of first pH adjuster, the pH can be maintained at 3.5-5.5.

[0089] Furthermore, the solvent used to prepare the passivation solution is deionized water, which is environmentally friendly and pollution-free.

[0090] Furthermore, the passivation process includes placing the material in a passivation solution and passivating it for 30-60 seconds at 20℃-30℃. This short immersion time helps to better preserve the metal's original color. Specifically, the passivation temperature is close to room temperature, such as 20℃, 23℃, 25℃, 28℃, or 30℃, and the passivation time can be 30s, 40s, 50s, or 60s.

[0091] The activation solution used in the PVD pre-activation treatment comprises: 50 g / L-150 g / L of sulfonic acid organic acid, 10 g / L-50 g / L of oxidant, 5 g / L-30 g / L of complexing agent, 0.1 g / L-5.0 g / L of nonionic surfactant, 0.01 g / L-2.00 g / L of corrosion inhibitor, and 1 g / L-10 g / L of second pH adjuster. Preferably, the activation solution used in the PVD pre-activation treatment comprises: 90 g / L-110 g / L of sulfonic acid organic acid, 25 g / L-35 g / L of oxidant, 13 g / L-18 g / L of complexing agent, 0.5 g / L-1.5 g / L of nonionic surfactant, 0.3 g / L-0.8 g / L of corrosion inhibitor, 3 g / L-7 g / L of second pH adjuster, with the balance being water. The composition of the activation solution for the PVD pre-activation treatment was optimized to further enhance the adhesion between the PVD coating and the electroplated coating.

[0092] Specifically, the content of sulfonic acid organic acids can be 50 g / L, 60 g / L, 70 g / L, 80 g / L, 90 g / L, 100 g / L, 110 g / L, 120 g / L, 130 g / L, 140 g / L, 150 g / L, etc. The content of oxidizing agents can be 10 g / L, 15 g / L, 20 g / L, 25 g / L, 30 g / L, 35 g / L, 40 g / L, 45 g / L, 50 g / L, etc. The content of complexing agents can be 5 g / L, 10 g / L, 15 g / L, 20 g / L, 25 g / L, 30 g / L, etc. The content of nonionic surfactants can be 0.1 g / L, 0.3 g / L, 0.5 g / L, 0.8 g / L, 1.0 g / L, 1.5 g / L, 2.0 g / L, 2.5 g / L, 3.0 g / L, 3.5 g / L, 4.0 g / L, 4.5 g / L, 5.0 g / L, etc. The content of corrosion inhibitors can be 0.01 g / L, 0.05 g / L, 0.08 g / L, 0.10 g / L, 0.20 g / L, 0.30 g / L, 0.40 g / L, 0.50 g / L, 0.60 g / L, 0.70 g / L, 0.80 g / L, 1.00 g / L, 1.30 g / L, 1.50 g / L, 1.80 g / L, 2.00 g / L, etc. The content of the second pH adjuster can be 1g / L, 2g / L, 3g / L, 4g / L, 5g / L, 6g / L, 7g / L, 8g / L, 9g / L, 10g / L, etc.

[0093] The components of the activation solution are described below:

[0094] In some embodiments, the sulfonic acid organic acid is selected from at least one of aminosulfonic acid and methanesulfonic acid. The sulfonic acid organic acid can be any one or more of the above. The sulfonic acid organic acid serves as the primary acid, providing H+. + It also complexes with metal ions, resulting in good solubility and less residue.

[0095] In some embodiments, the oxidant is selected from at least one of hydrogen peroxide solution and sodium percarbonate. The oxidant can be any one or more of the above. The mass fraction of the hydrogen peroxide solution is 20%-40%, such as 20%, 30%, 40%, etc. The addition of the oxidant is beneficial to the conversion of low-valence oxides, so as to accelerate the stripping.

[0096] In some embodiments, the complexing agent is selected from at least one of citric acid and ethylenediaminetetraacetic acid. The complexing agent can be any one or more of the above. By adding the complexing agent, Cu can be strongly complexed. 2+ / Ni + This prevents surface contamination and solution turbidity.

[0097] In some embodiments, the nonionic surfactant is selected from at least one of fatty alcohol polyoxyethylene ether and alkylphenol polyoxyethylene ether, and the nonionic surfactant can be any one or more of the above. Adding a nonionic surfactant can improve wetting and penetration effects, thus aiding in degreasing.

[0098] In some embodiments, when the chemical plating layer formed during the pretreatment process is a copper plating layer, the corrosion inhibitor is selected from at least one of benzotriazole and 5-methylbenzotriazole, and the corrosion inhibitor can be any one or more of the above. When the chemical plating layer formed during the pretreatment process is a nickel plating layer, the corrosion inhibitor is selected from at least one of thiourea and 2,4-dithiobiurea, and the corrosion inhibitor can be any one or more of the above. The addition of the corrosion inhibitor can form a film on the fresh metal surface, preventing over-etching and maintaining surface chemical activity.

[0099] In some embodiments, the second pH adjuster is selected from at least one of boric acid and sodium tetraborate, and the type of the second pH adjuster can be any one or more of the above. By adding the second pH adjuster, the pH of the buffer system is maintained, thereby maintaining stable activation efficiency.

[0100] In some embodiments, the solvent used to prepare the activation solution is deionized water, which is environmentally friendly and pollution-free.

[0101] Furthermore, the activation step includes: placing the material in an activation solution and activating it at 20℃-30℃ for 30s-60s. This short activation treatment effectively enhances the adhesion between the PVD coating and the electroplated coating. Specifically, the activation temperature is close to room temperature, such as 20℃, 23℃, 25℃, 28℃, or 30℃, and the activation time can be 30s, 40s, 50s, or 60s.

[0102] S4, PVD coating deposition

[0103] A PVD functional decorative layer is deposited on the material surface after the intermediate treatment in step S3. The coating has a variety of colors (such as IP black, IP blue, rose gold, etc.) and is also high in hardness and has excellent wear and scratch resistance.

[0104] In some embodiments, the thickness of the PVD functional decorative layer is controlled to be 0.2 μm-1.5 μm, such as 0.2 μm, 0.5 μm, 0.8 μm, 1.0 μm, 1.3 μm, 1.5 μm, etc. The PVD process used is selected from at least one of multi-arc ion plating and magnetron sputtering, and the PVD process can be any one of the above or a combination of both. The target material can be selected according to color requirements, and the coating material used is selected from at least one of zirconium (Zr), titanium (Ti), and chromium (Cr) targets.

[0105] In some embodiments, the introduced reaction gas is selected from at least one of nitrogen (N2), acetylene (C2H2), and oxygen (O2) to generate nitrides, carbides, or oxides of the desired color. In actual operation, the intermediate-treated material is loaded into the PVD vacuum chamber, a PVD functional decorative layer is deposited, and the vacuum level is controlled at 2.0 × 10⁻⁶. -3 Pa-5.0×10 -3 Pa, arc current of 60A-120A, bias voltage of -100V to -300V, deposition temperature ≤110°C, by adjusting the deposition conditions to form a uniform PVD coating.

[0106] Specifically, the vacuum level can be 2.0 × 10⁻⁶. -3 Pa, 3.0 × 10 -3 Pa, 4.0 × 10 -3 Pa, 5.0 × 10 -3 Pa, etc. Arc current can be 60A, 70A, 80A, 90A, 100A, 110A, 120A, etc. Bias voltage can be -100V, -150V, -200V, -250V, -300V, etc. Deposition temperature ≤110°C, such as 110°C, 105°C, 100°C, 95°C, 90°C, etc.

[0107] S5, Post-processing

[0108] A protective layer is formed on the material with PVD functional decorative layer to further enhance wear resistance and corrosion resistance.

[0109] In some embodiments, the process of forming the protective layer includes: applying a protective varnish to a material having a PVD functional decorative layer, followed by curing. Figure 2 The process involves chemical sealing / electrochemical passivation / UV protective coating. The protective coating material is selected from at least one of polyurethane acrylate, silicone resin, nano-silica, and hindered amine light stabilizers; any one or more of these materials can be used. The resulting protective layer has a thickness of 8μm-12μm.

[0110] This invention also provides a plastic part, which is prepared by the processing method provided in this invention, such as... Figure 3 As shown, from the inside out, it includes: a plastic substrate, a chemical plating layer (not shown), an electroplating layer (electroplated copper layer, electroplated semi-bright nickel layer, electroplated full-bright nickel layer, electroplated microporous nickel layer), a PVD functional decorative layer, and a sealing / passivation / UV layer. Depending on the protection level, copper plating or copper and nickel plating can be selected, as well as an optional outer protective paint layer.

[0111] It should be noted that this invention creatively uses an "electroplated layer" as the bottom layer and a "PVD layer" as the top layer, forming a composite coating structure of "plastic-electroplated-PVD". The electroplated layer provides a solid base and a perfect mirror effect, while the PVD layer imparts high surface hardness, rich colors, and top-level durability. It has the following advantages:

[0112] (1) In terms of appearance, it solves the problem of weak metallic feel of pure PVD on plastic and achieves a bright appearance comparable to electroplating.

[0113] (2) In terms of performance, it solves the problems of water electroplating being not wear-resistant and having a single color, and achieves wear resistance and corrosion resistance far exceeding those of pure water electroplating.

[0114] (3) In terms of environmental protection, since the PVD layer is the final surface, the thickness of the underlying electroplating layer can be appropriately reduced, and the amount of heavy metal pollutants such as chromium anhydride used and emitted in traditional electroplating is reduced from the source, making the process more environmentally friendly.

[0115] This invention, through specific intermediate processing, ensures excellent adhesion between the PVD coating and the underlying electroplated layer, overcoming the technical challenge of easy peeling between coatings of different properties. The processing method provided by this invention can be applied to plastic parts of various complex shapes, offering a novel surface treatment solution for high-end consumer electronics products (such as mobile phone frames, camera trim rings, and smartwatch casings) and automotive interior and exterior parts.

[0116] The features and performance of the present invention will be further described in detail below with reference to embodiments.

[0117] Example 1

[0118] This invention provides a method for processing plastic parts, specifically for manufacturing a black automotive interior door handle. The steps are as follows:

[0119] (1) Preprocessing

[0120] Using PC / ABS (polycarbonate / ABS alloy, purchased from SABIC, model MC1300) plastic material as raw material, a sample shaped like a door handle was obtained by injection molding.

[0121] Injection molding process:

[0122] Material temperature 260℃ (using PVD-coated TIN ultra-hard mirror mold);

[0123] Variable temperature injection molding technology is used: front mold 140℃ / rear mold 70℃;

[0124] The pressure holding pressure is 80-120MPa, and the pressure holding time is 6-8s.

[0125] like Figure 1As shown, the injection-molded sample was subjected to degreasing, roughening, neutralization, palladium activation, degumming, electroless nickel plating, and pre-nickel plating in sequence.

[0126] The degreasing agent used is Metex TS-40, which is an alkaline degreasing agent. The degreasing is done by heating and soaking at a temperature of 56°C.

[0127] The roughening process uses a mixture of chromic acid and sulfuric acid, with a chromic acid concentration of 400 g / L and a sulfuric acid concentration of 400 g / L. The mixture is heated (approximately 68°C) and soaked for 15 minutes.

[0128] Neutralization was achieved by soaking in a 20 ml / L sodium bisulfite solution for 1 min.

[0129] Palladium activation was performed using a colloidal palladium activation solution containing stannous chloride and palladium chloride. The concentration of stannous chloride in the activation solution was 3 g / L, and the concentration of palladium chloride was 280 ml / L.

[0130] Degelatinization was performed using UDIQUE 8812 HC at a concentration of 100 ml / L, followed by soaking for 1.5 min.

[0131] The steps for electroless nickel plating are as follows: Immerse the workpiece in an electroless plating solution containing nickel ions and sodium hypophosphite. The concentration of nickel ions in the solution is 5.8 g / L, and the concentration of sodium hypophosphite is 20 g / L. The electroless nickel plating temperature is 30℃, the pH value is 8.2, and the reaction time is 7 min.

[0132] Pre-plating nickel: The workpiece is immersed in a plating solution containing nickel sulfate and nickel chloride. The concentration of nickel sulfate in the plating solution is 240 g / L, and the concentration of nickel chloride is 48 g / L. The pre-plating temperature is 56℃, the pH value is 4.0, and the plating time is 4 min.

[0133] (2) Electroplating deposition

[0134] On the pre-treated plastic parts, electroplating is performed, sequentially plating a copper layer (25μm), a semi-bright nickel layer (14μm), a bright nickel layer (8μm), and a microporous nickel layer (2μm).

[0135] During copper plating, the workpiece is immersed in a plating solution containing copper sulfate and sulfuric acid. The concentration of copper sulfate in the solution is 200 g / L, and the concentration of sulfuric acid is 70 g / L. The temperature of the plating solution is controlled at 24℃, and the plating time is 2400 s.

[0136] To prepare the semi-bright nickel layer, the workpiece is immersed in a plating solution containing nickel sulfate and nickel chloride. The concentration of nickel sulfate in the plating solution is 300 g / L, and the concentration of nickel chloride is 40 g / L. The temperature of the plating solution is controlled at 55℃, the pH value is 3.8, and the plating time is 1200 s.

[0137] To prepare the bright nickel layer, the workpiece is immersed in a plating solution containing nickel sulfate and nickel chloride. The concentration of nickel sulfate in the plating solution is 300 g / L, and the concentration of nickel chloride is 55 g / L. The temperature of the plating solution is controlled at 55℃, the pH value is 4.0, and the plating time is 800 s.

[0138] To prepare the microporous nickel layer, the workpiece is immersed in a plating solution containing nickel sulfate and nickel chloride. The concentration of nickel sulfate in the plating solution is 300 g / L, and the concentration of nickel chloride is 75 g / L. The temperature of the plating solution is controlled at 55℃, the pH value is 4.2, and the plating time is 240 s.

[0139] Current density controlled at 3 A / dm 2 .

[0140] (3) Intermediate processing

[0141] like Figure 1 and Figure 2 As shown, the parts are thoroughly cleaned after water electroplating to remove electroplating solution residue, and then activated with acid. Figure 1 Activation) and passivation treatment ( Figure 1 Passivation), baking and drying. Afterwards, degreasing, cleaning (deionized water washing), and pre-PVD activation treatment (…). Figure 2 The process includes activation, cleaning (deionized water washing), cleaning (deionized water washing) (using a double countercurrent hot water wash at a temperature of 60°C to fully remove the activation solution residue from the workpiece surface), and baking.

[0142] The acid solution used for acid activation is a 10% sulfuric acid aqueous solution, and the soaking time is 1 minute.

[0143] The passivation solution used in the passivation treatment consists of: 0.5 g / L main film-forming agent, 22 g / L oxidant, 4.5 g / L organic corrosion inhibitor, 7.5 g / L silane coupling agent, 70 g / L first pH adjuster, and the balance being deionized water. The main film-forming agent is 8-hydroxyquinoline, the oxidant is sodium molybdate, the organic corrosion inhibitor is 1-phenyl-5-mercaptotetrazole, the silane coupling agent is γ-aminopropyltriethoxysilane, and the first pH adjuster is sodium citrate. The passivation treatment process is carried out at 25℃ for 40 seconds.

[0144] The oil removal process uses Metex TS-40 and employs a heated immersion method at a temperature of 56°C.

[0145] The activation solution used in the PVD pre-activation treatment consists of: 100 g / L sulfonic acid, 30 g / L oxidant, 15 g / L complexing agent, 1 g / L nonionic surfactant, 0.5 g / L corrosion inhibitor, 5 g / L secondary pH adjuster, and the balance being deionized water. The sulfonic acid is aminosulfonic acid, the oxidant is 30% hydrogen peroxide, the complexing agent is citric acid, the nonionic surfactant is fatty alcohol polyoxyethylene ether, the corrosion inhibitor is thiourea, and the secondary pH adjuster is boric acid. The activation temperature is controlled at 25℃, and the activation time is 40 seconds.

[0146] (4) PVD coating deposition

[0147] After surface cleaning and activation, a zirconium carbide (ZrCN) coating with a thickness of approximately 0.8 μm was deposited using magnetron sputtering on a zirconium target (Zr) under a nitrogen (N2) and a small amount of acetylene (C2H2) atmosphere, exhibiting a deep space black color. Parameters: Vacuum degree: 3.5 × 10⁻⁶ -3 Pa, sputtering power 400W, bias voltage -150V, deposition temperature 100°C.

[0148] (5) Post-processing

[0149] A UV-curable protective coating is applied, the type of which is CS8002, and the resulting protective layer is 10μm thick.

[0150] Example 2

[0151] This invention provides a method for processing plastic parts, specifically for manufacturing a black automotive interior door handle. The steps are as follows:

[0152] (1) Preprocessing

[0153] Same as Example 1.

[0154] (2) Electroplating deposition

[0155] On the pre-treated plastic parts, electroplating is performed, and copper layer (20μm), semi-bright nickel layer (12μm), bright nickel layer (6μm), and microporous nickel layer (1μm) are plated in sequence.

[0156] During copper plating, the workpiece is immersed in a plating solution containing copper sulfate and sulfuric acid. The concentration of copper sulfate in the solution is 200 g / L, and the concentration of sulfuric acid is 70 g / L. The temperature of the plating solution is controlled at 22℃, and the plating time is 2600 s.

[0157] To prepare the semi-bright nickel layer, the workpiece is immersed in a plating solution containing nickel sulfate and nickel chloride. The concentration of nickel sulfate in the plating solution is 300 g / L, and the concentration of nickel chloride is 40 g / L. The temperature of the plating solution is controlled at 50℃, the pH value is 3.8, and the plating time is 1300 s.

[0158] To prepare the bright nickel layer, the workpiece is immersed in a plating solution containing nickel sulfate and nickel chloride. The concentration of nickel sulfate in the plating solution is 300 g / L, and the concentration of nickel chloride is 55 g / L. The temperature of the plating solution is controlled at 50℃, the pH value is 4.0, and the plating time is 860 s.

[0159] To prepare the microporous nickel layer, the workpiece is immersed in a plating solution containing nickel sulfate and nickel chloride. The concentration of nickel sulfate in the plating solution is 300 g / L, and the concentration of nickel chloride is 75 g / L. The temperature of the plating solution is controlled at 50℃, the pH value is 4.2, and the plating time is 270 s.

[0160] Current density controlled at 2A / dm 2 .

[0161] (3) Intermediate processing

[0162] like Figure 1 and Figure 2 As shown, the parts are thoroughly cleaned after water electroplating to remove electroplating solution residue, and then activated with acid. Figure 1 Activation) and passivation treatment ( Figure 1 Passivation), baking and drying. Afterwards, degreasing, cleaning (deionized water washing), and pre-PVD activation treatment (…). Figure 2 The process includes activation, cleaning (deionized water washing), cleaning (deionized water washing) (using a double countercurrent hot water wash at a temperature of 60°C to fully remove the activation solution residue from the workpiece surface), and baking.

[0163] The acid solution used for acid activation is a 10% sulfuric acid aqueous solution, and the soaking time is 1 minute.

[0164] The passivation solution used in the passivation treatment consists of: 0.1 g / L of main film-forming agent, 20 g / L of oxidant, 1 g / L of organic corrosion inhibitor, 5 g / L of silane coupling agent, 50 g / L of first pH adjuster, and the balance being deionized water. The main film-forming agent is 8-hydroxyquinoline, the oxidant is sodium molybdate, the organic corrosion inhibitor is 1-phenyl-5-mercaptotetrazole, the silane coupling agent is γ-aminopropyltriethoxysilane, and the first pH adjuster is sodium citrate. The passivation treatment process is carried out at 20℃ for 60 seconds.

[0165] The oil removal process uses Metex TS-40 and employs a heated immersion method at a temperature of 56°C.

[0166] The activation solution used in the PVD pre-activation treatment consists of: 50 g / L sulfonic acid organic acid, 10 g / L oxidant, 5 g / L complexing agent, 0.1 g / L nonionic surfactant, 0.01 g / L corrosion inhibitor, 1 g / L secondary pH adjuster, and the balance being deionized water. The sulfonic acid organic acid is aminosulfonic acid, the oxidant is 30% hydrogen peroxide, the complexing agent is citric acid, the nonionic surfactant is fatty alcohol polyoxyethylene ether, the corrosion inhibitor is thiourea, and the secondary pH adjuster is boric acid. The activation temperature is controlled at 20℃, and the activation time is 60 seconds.

[0167] (4) PVD coating deposition

[0168] After surface cleaning and activation, a zirconium carbide (ZrCN) coating with a thickness of approximately 0.2 μm was deposited using magnetron sputtering on a zirconium target (Zr) under a nitrogen (N2) and a small amount of acetylene (C2H2) atmosphere, exhibiting a deep space black color. Parameters: Vacuum degree: 2.0 × 10⁻⁶ -3 Pa, sputtering power 320W, bias voltage -100V, deposition temperature 90°C.

[0169] (5) Post-processing

[0170] A UV-curable protective coating is applied, the type of which is CS8002, and the thickness of the resulting protective layer is 8μm.

[0171] Example 3

[0172] This invention provides a method for processing plastic parts, specifically for manufacturing a black automotive interior door handle. The steps are as follows:

[0173] (1) Preprocessing

[0174] Same as Example 1.

[0175] (2) Electroplating deposition

[0176] On the pre-treated plastic parts, electroplating is performed, and copper layer (30μm), semi-bright nickel layer (18μm), bright nickel layer (10μm), and microporous nickel layer (3μm) are plated in sequence.

[0177] During copper plating, the workpiece is immersed in a plating solution containing copper sulfate and sulfuric acid. The concentration of copper sulfate in the solution is 200 g / L, and the concentration of sulfuric acid is 70 g / L. The temperature of the plating solution is controlled at 26℃, and the plating time is 2200 s.

[0178] To prepare the semi-bright nickel layer, the workpiece is immersed in a plating solution containing nickel sulfate and nickel chloride. The concentration of nickel sulfate in the plating solution is 300 g / L, and the concentration of nickel chloride is 40 g / L. The temperature of the plating solution is controlled at 60℃, the pH value is 3.8, and the plating time is 1100 s.

[0179] To prepare the bright nickel layer, the workpiece is immersed in a plating solution containing nickel sulfate and nickel chloride. The concentration of nickel sulfate in the plating solution is 300 g / L, and the concentration of nickel chloride is 55 g / L. The temperature of the plating solution is controlled at 60℃, the pH value is 4.0, and the plating time is 740 s.

[0180] To prepare the microporous nickel layer, the workpiece is immersed in a plating solution containing nickel sulfate and nickel chloride. The concentration of nickel sulfate in the plating solution is 300 g / L, and the concentration of nickel chloride is 75 g / L. The temperature of the plating solution is controlled at 60℃, the pH value is 4.2, and the plating time is 210 s.

[0181] Current density controlled at 5 A / dm 2 .

[0182] (3) Intermediate processing

[0183] like Figure 1 and Figure 2 As shown, the parts are thoroughly cleaned after water electroplating to remove electroplating solution residue, and then activated with acid. Figure 1 Activation) and passivation treatment ( Figure 1 Passivation), baking and drying. Afterwards, degreasing, cleaning (deionized water washing), and pre-PVD activation treatment (…). Figure 2 The process includes activation, cleaning (deionized water washing), cleaning (deionized water washing) (using a double countercurrent hot water wash at a temperature of 60°C to fully remove the activation solution residue from the workpiece surface), and baking.

[0184] The acid solution used for acid activation is a 10% sulfuric acid aqueous solution, and the soaking time is 1 minute.

[0185] The passivation solution used in the passivation treatment consists of: 0.8 g / L of main film-forming agent, 25 g / L of oxidant, 8 g / L of organic corrosion inhibitor, 10 g / L of silane coupling agent, 90 g / L of primary pH adjuster, and the balance being deionized water. The main film-forming agent is 8-hydroxyquinoline, the oxidant is sodium molybdate, the organic corrosion inhibitor is 1-phenyl-5-mercaptotetrazole, the silane coupling agent is γ-aminopropyltriethoxysilane, and the primary pH adjuster is sodium citrate. The passivation treatment process is carried out at 30℃ for 30 seconds.

[0186] The oil removal process uses Metex TS-40 and employs a heated immersion method at a temperature of 56°C.

[0187] The activation solution used in the PVD pre-activation treatment consists of: 150 g / L sulfonic acid organic acid, 50 g / L oxidant, 30 g / L complexing agent, 5 g / L nonionic surfactant, 2 g / L corrosion inhibitor, 10 g / L secondary pH adjuster, and the balance being deionized water. The sulfonic acid organic acid is aminosulfonic acid, the oxidant is 30% hydrogen peroxide, the complexing agent is citric acid, the nonionic surfactant is fatty alcohol polyoxyethylene ether, the corrosion inhibitor is thiourea, and the secondary pH adjuster is boric acid. The activation temperature is controlled at 30℃, and the activation time is 30 seconds.

[0188] (4) PVD coating deposition

[0189] After surface cleaning and activation, a zirconium carbide (ZrCN) coating with a thickness of approximately 1.5 μm was deposited using magnetron sputtering on a zirconium target (Zr) under a nitrogen (N2) and a small amount of acetylene (C2H2) atmosphere, exhibiting a deep space black color. Parameters: Vacuum degree: 5.0 × 10⁻⁶ -3 Pa, sputtering power 480W, bias voltage -300V, deposition temperature 110°C.

[0190] (5) Post-processing

[0191] A UV-curable protective coating is applied, the type of which is CS8002, and the resulting protective layer is 12μm thick.

[0192] Example 4

[0193] The only difference from Example 1 is that the passivation solution used in the passivation treatment comprises: 0.1 g / L of main film-forming agent, 20 g / L of oxidant, 1 g / L of organic corrosion inhibitor, 5 g / L of silane coupling agent, 50 g / L of first pH adjuster, and the balance being deionized water. The specific raw materials for each component are the same as in Example 1.

[0194] Example 5

[0195] The only difference from Example 1 is that the passivation solution used in the passivation treatment comprises: 0.8 g / L of main film-forming agent, 25 g / L of oxidant, 8 g / L of organic corrosion inhibitor, 10 g / L of silane coupling agent, 90 g / L of first pH adjuster, and the balance being deionized water. The specific raw materials for each component are the same as in Example 1.

[0196] Example 6

[0197] The only difference from Example 1 is that the activation solution used in the PVD pre-activation treatment comprises: 50 g / L sulfonic acid organic acid, 10 g / L oxidant, 5 g / L complexing agent, 0.1 g / L nonionic surfactant, 0.01 g / L corrosion inhibitor, 1 g / L second pH adjuster, and the balance being deionized water. The specific raw materials for each component are the same as in Example 1.

[0198] Example 7

[0199] The only difference from Example 1 is that the activation solution used in the PVD pre-activation treatment comprises: 150 g / L of sulfonic acid organic acid, 50 g / L of oxidant, 30 g / L of complexing agent, 5 g / L of nonionic surfactant, 2 g / L of corrosion inhibitor, 10 g / L of second pH adjuster, and the remainder being deionized water. The specific raw materials for each component are the same as in Example 1.

[0200] Example 8

[0201] The only difference from Example 1 is that the main film-forming agent in the passivation solution used for passivation treatment is replaced with 2-methylimidazole.

[0202] Example 9

[0203] The only difference from Example 1 is that the sulfonic acid organic acids in the activation solution used for the PVD pre-activation treatment are replaced with methanesulfonic acid.

[0204] Comparative Example 1

[0205] The only difference from Example 1 is that steps (1) and (2) are performed, followed by trivalent black chromium.

[0206] To prepare trivalent black chromium, the workpiece is immersed in a plating bath containing Trimac Eclipse CS and Trimac Eclipse CR. The concentration of Trimac Eclipse CS in the plating bath is 280 g / L, and the concentration of Trimac Eclipse CR is 160 ml / L. The plating bath temperature is controlled at 45℃, the pH value is 3.4, and the plating time is 180 s.

[0207] Comparative Example 2

[0208] The only difference from Example 1 is that PVD deposition is performed only on the substrate, and the specific steps and parameters are the same as step (4) of Example 1.

[0209] Comparative Example 3

[0210] The only difference from Example 1 is that no passivation treatment is performed.

[0211] Comparative Example 4

[0212] The only difference from Example 1 is that no PVD pre-activation treatment is performed.

[0213] Comparative Example 5

[0214] The only difference from Example 1 is that the passivation solution used in the passivation treatment comprises: 0.05 g / L of main film-forming agent, 30 g / L of oxidant, 10 g / L of organic corrosion inhibitor, 2 g / L of silane coupling agent, 70 g / L of first pH adjuster, and the balance being deionized water. The specific raw materials for each component are the same as in Example 1.

[0215] Comparative Example 6

[0216] The only difference from Example 1 is that the passivation solution used in the passivation treatment comprises: 1 g / L of main film-forming agent, 15 g / L of oxidant, 0.5 g / L of organic corrosion inhibitor, 15 g / L of silane coupling agent, 70 g / L of first pH adjuster, and the balance being deionized water. The specific raw materials for each component are the same as in Example 1.

[0217] Comparative Example 7

[0218] The only difference from Example 1 is that the activation solution used in the PVD pre-activation treatment consists of: 30 g / L sulfonic acid organic acid, 60 g / L oxidant, 3 g / L complexing agent, 8 g / L nonionic surfactant, 3 g / L corrosion inhibitor, 5 g / L second pH adjuster, and the remainder is deionized water. The specific raw materials for each component are the same as in Example 1.

[0219] Comparative Example 8

[0220] The only difference from Example 1 is that the activation solution used in the PVD pre-activation treatment comprises: 200 g / L sulfonic acid organic acid, 5 g / L oxidant, 20 g / L complexing agent, 0.05 g / L nonionic surfactant, 0.05 g / L corrosion inhibitor, 5 g / L second pH adjuster, and the balance being deionized water. The specific raw materials for each component are the same as in Example 1.

[0221] Comparative Example 9

[0222] The only difference from Example 1 is that the passivation solution used in the passivation treatment consists of a chromic acid solution with a concentration of 100 g / L and an immersion time of 1 min.

[0223] Comparative Example 10

[0224] The only difference from Example 1 is that the activation solution used in the PVD pre-activation treatment consists of a mixture of ammonium persulfate at a concentration of 5 g / L and sulfuric acid at a concentration of 2 ml / L, with the remainder being deionized water, and the soaking time is 1.5 min.

[0225] Comparison of Test Methods and Results

[0226] The samples prepared according to the embodiments and comparative examples of the present invention were compared and tested, and the results are shown in Table 1 and Table 2.

[0227] Test method:

[0228] (1) Appearance, using visual inspection.

[0229] (2) Abrasion resistance: RCA paper tape abrasion resistance test, refer to GB / T 32020-2015.

[0230] (3) Hardness: Pencil hardness, refer to GB / T 6739-2022.

[0231] (4) Corrosion resistance: acidic salt spray test, refer to GB / T 10125-2021.

[0232] (5) Bonding strength: The cross-cut method is adopted, referring to GB / T 9286-2001.

[0233] Table 1. Test results of samples prepared in the examples

[0234]

[0235] Table 2 Test results of samples prepared in the comparative example

[0236]

[0237] As shown in Tables 1 and 2, this invention forms a composite coating structure of "plastic-electroplating-PVD" by using an "electroplating layer" as the bottom layer and a "PVD layer" as the top layer. The electroplating layer provides a solid base and a perfect mirror finish, while the PVD layer imparts high surface hardness, rich colors, and top-level durability. Through specific intermediate treatments, this invention ensures excellent adhesion between the PVD coating and the underlying electroplating layer, overcoming the technical challenge of easy peeling between coatings of different properties.

[0238] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for processing plastic parts, characterized in that, include: Pretreatment: Plastic materials are used as raw materials for molding, and then a conductive chemical plating layer is formed on the surface; Electroplating deposition: Electroplating is performed on the pretreated material to form an underlying electroplating layer; The electroplating process includes: sequentially forming a copper layer, a semi-bright nickel layer, a bright nickel layer, and a microporous nickel layer; Intermediate treatment: The material with the underlying electroplated layer is subjected to acid activation and passivation treatment, followed by PVD pre-activation treatment; wherein, the acid solution used in the acid activation process is a sulfuric acid solution with a mass fraction of 8%-12%; the passivation solution used in the passivation treatment comprises: 0.1g / L-0.8g / L of main film-forming agent, 20g / L-25g / L of oxidant, 1g / L-8g / L of organic corrosion inhibitor, 5g / L-10g / L of silane coupling agent, and 50g / L-90g / L of first pH value adjuster; the main film-forming agent is selected from 8-hydroxyquinoline, 8-hydroxy... The passivation solution contains at least one of an azo derivative of quinoline and 2-methylimidazolium; the oxidant in the passivation solution is selected from at least one of sodium molybdate, potassium molybdate, and zinc molybdate; the organic corrosion inhibitor is selected from at least one of 1-phenyl-5-mercaptotetrazole and 5-mercapto-1-methyltetrazole; the silane coupling agent is selected from at least one of γ-aminopropyltriethoxysilane and γ-glycidoxypropyltrimethoxysilane; the first pH adjuster is selected from at least one of sodium citrate and potassium citrate; the solvent used to prepare the passivation solution is deionized water; the activation treatment used in the PVD pre-activation process... The solution comprises: 50 g / L-150 g / L of sulfonic acid organic acid, 10 g / L-50 g / L of oxidant, 5 g / L-30 g / L of complexing agent, 0.1 g / L-5.0 g / L of nonionic surfactant, 0.01 g / L-2.00 g / L of corrosion inhibitor, and 1 g / L-10 g / L of second pH adjuster; the sulfonic acid organic acid is selected from at least one of aminosulfonic acid and methanesulfonic acid; the oxidant is selected from at least one of hydrogen peroxide solution and sodium percarbonate; the mass fraction of the hydrogen peroxide solution is 20%-40%; the complexing agent is selected from citric acid and... The active ingredient is selected from at least one of ethylenediaminetetraacetic acid; the nonionic surfactant is selected from at least one of fatty alcohol polyoxyethylene ether and alkylphenol polyoxyethylene ether; when the chemical plating layer formed during the pretreatment is a copper plating layer, the corrosion inhibitor is selected from at least one of benzotriazole and 5-methylbenzotriazole; when the chemical plating layer formed during the pretreatment is a nickel plating layer, the corrosion inhibitor is selected from at least one of thiourea and 2,4-dithiobiurea; the second pH adjuster is selected from at least one of boric acid and sodium tetraborate; the solvent used to prepare the activation solution is deionized water. PVD coating deposition: A PVD functional decorative layer is deposited on the surface of the material after the intermediate treatment; Post-processing involves forming a protective layer on the material having the PVD functional decorative layer.

2. The processing method for plastic parts according to claim 1, characterized in that, The passivation solution is composed of the following: 0.4 g / L-0.6 g / L main film-forming agent, 21 g / L-23 g / L oxidant, 3 g / L-6 g / L organic corrosion inhibitor, 6 g / L-9 g / L silane coupling agent, 65 g / L-75 g / L first pH adjuster, and the balance being deionized water.

3. The processing method for plastic parts according to claim 2, characterized in that, The material is placed in the passivation solution and passivated for 30-60 seconds at 20-30°C.

4. The processing method for plastic parts according to claim 1, characterized in that, The activation solution used in the PVD pre-activation treatment has the following composition: 90g / L-110g / L of sulfonic acid organic acid, 25g / L-35g / L of oxidant, 13g / L-18g / L of complexing agent, 0.5g / L-1.5g / L of nonionic surfactant, 0.3g / L-0.8g / L of corrosion inhibitor, 3g / L-7g / L of second pH adjuster, and the balance being deionized water.

5. The processing method for plastic parts according to claim 4, characterized in that, The material is placed in the activation solution and activated at 20℃-30℃ for 30s-60s.

6. The method for processing plastic parts according to any one of claims 1-5, characterized in that, The intermediate processing includes: acid activation and passivation of the material with the underlying electroplated layer, followed by baking, degreasing, and cleaning, and then PVD pre-activation treatment, followed by cleaning and baking.

7. The processing method for plastic parts according to claim 1, characterized in that, The copper layer has a thickness of 20μm-30μm, the semi-bright nickel layer has a thickness of 12μm-18μm, the bright nickel layer has a thickness of 6μm-10μm, and the microporous nickel layer has a thickness of 1μm-3μm.

8. The method for processing plastic parts according to claim 7, characterized in that, When preparing the copper layer, the temperature of the electroplating solution is controlled at 22℃-26℃, and the electroplating time is 2200s-2600s; And / or, when preparing the semi-bright nickel layer, the temperature of the electroplating solution is controlled at 50℃-60℃ and the electroplating time is 1100s-1300s; And / or, when preparing the bright nickel layer, the temperature of the electroplating solution is controlled at 50℃-60℃ and the electroplating time is 740s-860s; And / or, when preparing the microporous nickel layer, the temperature of the electroplating solution is controlled at 50℃-60℃ and the electroplating time is 210s-270s; And / or, control the current density during the electroplating process to be 2 A / dm³. 2 -5A / dm 2 .

9. The processing method for plastic parts according to claim 1, characterized in that, The pretreatment process includes: after the plastic material is injection molded, it is sequentially subjected to degreasing, roughening, neutralization, palladium activation, degumming, and chemical plating.

10. The processing method for plastic parts according to claim 1, characterized in that, The PVD coating deposition process has at least one of the following characteristics A3-E3: Feature A3: Control the thickness of the PVD functional decorative layer to be 0.2μm-1.5μm; Feature B3: The PVD process used is selected from at least one of multi-arc ion plating and magnetron sputtering; Feature C3: The coating material used is selected from at least one of zirconium target, titanium target and chromium target; Feature D3: The reactant gas is selected from at least one of nitrogen, acetylene, and oxygen; Feature E3: The material that has undergone the intermediate treatment is loaded into a PVD vacuum chamber, and the PVD functional decorative layer is deposited, with the vacuum level controlled at 2.0 × 10⁻⁶. -3 Pa-5.0×10 -3 Pa, arc current of 60A-120A, bias voltage of -100V to -300V, deposition temperature ≤110°C.

11. The processing method for plastic parts according to claim 1, characterized in that, The process of forming the protective layer includes: coating a protective varnish onto a material having the PVD functional decorative layer, and then curing it; the protective varnish is selected from at least one of polyurethane acrylate, silicone resin, nano silica and hindered amine light stabilizer; And / or, the thickness of the protective layer is 8μm-12μm.

12. A plastic part, characterized in that, It is prepared by the processing method of any one of claims 1-11.

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