Multi-color low-cost plastic vacuum plating process

Abstract

The invention relates to the technical field of plastic vacuum plating, in particular to a multi-color low-cost plastic vacuum plating process which comprises the following steps: performing surface treatment on a colored material injection molding base material, and arranging a Pramar bottom above the colored material injection molding base material; the Pramar substrate is coated with color primer, and a layer of metal film PVD coating is formed through the physical vapor deposition technology; the PVD plating layer is coated with color intermediate paint and transparent UV protective paint, and a layer of metal film PVD plating layer is formed again through the physical vapor deposition technology; and the new PVD plating layer is coated with intermediate paint in a proper color, meanwhile, the outermost layer is coated with transparent UV finish paint, and a finished product is obtained after the paint is dried. Through material and coating optimization, a single-color NCVM process is reduced to three times or four times of coating. Meanwhile, the two-color NCVM process is simplified from eight times of coating and eight times of baking to six times of coating and six times of baking, and the two-color NCVM process is superior to a traditional process in the aspects of color richness, cost control, production process simplification and yield improvement.

Description

Technical Field

[0001] The present invention relates to the technical field of plastic vacuum plating, and particularly to a multi-color and low-cost plastic vacuum electroplating process. Background Art

[0002] In the current manufacturing industry, the injection molding plus surface single-color NCVM (i.e., plastic vacuum coating) technology has been widely applied. This technology endows products with unique appearance texture by plating a layer of metal film on the plastic surface. However, when it comes to two-color or multi-color NCVM processes, due to the diversification of colors, some limitations have been encountered in the process. The traditional single-color NCVM process usually requires 5 coatings and 5 bakings to complete, while two-color or multi-color products require 8 coatings and 8 bakings. Such a process flow is not only complex but also time-consuming. As the number of coating layers increases, the processing windows of materials and coatings become narrower and narrower, which directly affects the first-pass yield of mass production and the passing rate of tests. Due to cost and process limitations, two-color and multi-color NCVM processes have not been widely applied.

[0003] However, the emergence of a new multi-color and low-cost plastic vacuum electroplating process has successfully solved the above problems. This new technology not only simplifies the process flow, reduces the manufacturing cost, but also significantly improves the first-pass yield of each production link. It enables products to achieve higher production efficiency while maintaining high quality. Therefore, this new process has been widely applied in the industry and is expected to become the mainstream of future plastic vacuum coating technology. Summary of the Invention

[0004] In view of the deficiencies of the prior art, the present invention discloses a multi-color and low-cost plastic vacuum electroplating process to solve the above problems.

[0005] The present invention is achieved through the following technical solutions:

[0006] The present invention provides a multi-color and low-cost plastic vacuum electroplating process, including the following steps:

[0007] Perform surface treatment on the colored material injection substrate to ensure good adhesion between the coating and the plastic substrate, and set a Pramar base above it;

[0008] Coat a color primer on the Pramar base and form a metal thin film PVD coating through physical vapor deposition technology;

[0009] Coat a color intermediate paint and a transparent UV protective paint on the PVD coating, and form a metal thin film PVD coating again through physical vapor deposition technology;

[0010] Select a suitable color intermediate paint to coat on the new PVD coating, and at the same time coat a transparent UV topcoat on the outermost layer. After the paint dries, the finished product is obtained.

[0011] In one embodiment, the colored material injection-molded substrate is ABS plastic. When the colored material injection-molded substrate is subjected to surface treatment, sandblasting or chemical etching methods are used to remove oil and impurities on the surface, ensuring good adhesion between the coating and the substrate.

[0012] In one embodiment, the Pramar bottom material is acrylic resin, which is used to provide adhesion and plays a protective role in the subsequent PVD coating process, preventing adverse reactions caused by direct contact between the metal film and the plastic substrate. The coating thickness of Pramar bottom is controlled between 10 - 20 microns to ensure its uniformity and sufficient coverage.

[0013] In one embodiment, the color primer and intermediate paint are composed of polymer, pigment, solvent and various additives. Among them, the polymer serves as the film-forming substance, and its proportion is controlled between 30% - 50% to ensure the elasticity and adhesion of the paint film. The type and proportion of the solvent need to be selected according to the type of the polymer used and environmental requirements, and are controlled within the range of 20% - 40%. The addition amount of the additives does not exceed 5%.

[0014] In one embodiment, physical vapor deposition technology uses plasma or thermal evaporation to deposit metal materials onto the colored material injection-molded substrate.

[0015] In one embodiment, the thickness of the PVD coating is controlled between 50 - 100 nanometers.

[0016] In one embodiment, the coating thicknesses of the transparent UV protective paint and UV topcoat are respectively controlled between 10 - 20 microns and 20 - 30 microns to ensure the uniformity of the paint film and sufficient protection, and at the same time use the UV curing technology for the applied paint layer.

[0017] In one embodiment, the entire electroplating process is carried out in a vacuum environment to ensure the uniformity and adhesion of the metal film, and at the same time reduce environmental pollution.

[0018] In one embodiment, surface treatment is carried out after the PVD coating, using ion implantation technology or chemical plating technology to enhance the surface performance of the coating.

[0019] In one embodiment, in order to ensure the long-term stability and durability of the electroplated layer, an aging test is carried out after electroplating to simulate the performance of the product in the actual use environment, and the electroplating process is optimized according to the test results.

[0020] The beneficial effects of the present invention are:

[0021] The multi-color low-cost plastic vacuum plating technology involved in the present invention realizes the innovation of the two-color or multi-color NCVM (plastic vacuum plating) process by effectively combining colored plastics with color coatings and through the way of process superposition. This technology has brought new breakthroughs to the appearance process of 3C products. Compared with the single-color treatment method of five coatings and five bakings adopted by the traditional NCVM (plastic vacuum plating) process, the new low-cost plastic vacuum plating process of the present invention reduces the single-color NCVM process to three or four coatings through the optimization of materials and coatings. At the same time, the two-color NCVM process is simplified from eight coatings and eight bakings to six coatings and six bakings, and it is superior to the traditional process in terms of color richness, cost control, production process simplification and yield improvement. Brief Description of the Drawings

[0022] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0023] Figure 1 It is a coating decomposition diagram of the ordinary single-color conventional NVCM process;

[0024] Figure 2 It is a coating decomposition diagram of the ordinary two-color conventional NVCM process;

[0025] Figure 3 It is a coating decomposition diagram of the two-color low-cost plastic vacuum electroplating process;

[0026] Figure 4 It is a coating decomposition diagram of the multi-color low-cost plastic vacuum electroplating process. Detailed Description of the Embodiments

[0027] To make the objectives, technical solutions and advantages of the embodiments of the present invention clearer, the following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the drawings in the embodiments of the present invention. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention.

[0028] In one embodiment, a multi-color low-cost plastic vacuum electroplating process is provided, including the following steps:

[0029] Perform surface treatment on the colored material injection substrate to ensure good adhesion between the coating and the plastic substrate, and set a Pramar bottom above;

[0030] Apply a color primer on the Pramar base and form a metal thin film PVD coating through physical vapor deposition technology;

[0031] Apply a color intermediate paint and a transparent UV protective paint on the PVD coating, and form another metal thin film PVD coating through physical vapor deposition technology;

[0032] Select a suitable color intermediate paint to apply on the new PVD coating, and at the same time apply a transparent UV topcoat on the outermost layer. After the paint dries, the finished product is obtained.

[0033] The colored material injection molding substrate in this embodiment is ABS plastic. When the colored material injection molding substrate is subjected to surface treatment, sandblasting or chemical etching methods are used to remove oil stains and impurities on the surface, ensuring good adhesion between the coating and the substrate.

[0034] After the surface treatment of the ABS plastic substrate is completed, first apply a layer of Pramar base. The application of Pramar base is to further enhance the adhesion between the coating and the substrate and provide a smooth surface so that the subsequent metal thin film PVD coating can be evenly covered. After applying Pramar base, appropriate drying treatment is required to ensure that the primer can be fully cured.

[0035] Next, apply a color primer on the Pramar base. This step is to endow the product with a specific color effect. The choice of color primer depends on the color required for the final product, which can be a single color or a multi-color combination. After applying the color primer, drying treatment is also required to ensure that the color primer can firmly adhere to the Pramar base.

[0036] On the surface of the dried color primer, form a metal thin film through physical vapor deposition technology (PVD). The PVD coating can not only provide metallic luster but also further enhance the corrosion resistance and wear resistance of the product. The thickness and metal type of the coating can be adjusted according to the specific requirements of the product.

[0037] On the PVD coating, apply a layer of color intermediate paint and a transparent UV protective paint. The application of the color intermediate paint is to increase the color depth and layering of the product, while the transparent UV protective paint is used to protect the metal thin film and the color intermediate paint from the influence of the external environment, such as ultraviolet radiation and chemical erosion. After the application is completed, form another metal thin film through PVD treatment agent to enhance the metallic texture of the product.

[0038] Finally, a suitable colored primer is applied on the new PVD coating, and a transparent UV topcoat is applied on the outermost layer. When selecting the colored primer, color matching can be carried out according to the design requirements to achieve the best visual effect. After applying the transparent UV topcoat, the product needs to be subjected to final drying and curing processes to ensure that all coatings are firmly bonded together to form the final finished product.

[0039] In one embodiment, the Pramar base material is a formulation based on acrylic resin, and the main function of this material is to provide strong adhesion. During the subsequent PVD (Physical Vapor Deposition) coating process, the Pramar base plays a crucial protective role. Its presence can effectively prevent the direct contact between the metal film and the plastic substrate, thus avoiding possible adverse chemical reactions.

[0040] In one embodiment, to ensure that the primer can evenly cover the surface of the substrate and provide an adequate protective layer, the coating thickness of the Pramar base is strictly controlled between 10 and 20 microns. Such a thickness range not only ensures the uniformity of the primer but also guarantees its sufficient covering power to achieve the best protective effect.

[0041] In one embodiment, during the manufacturing process of the colored primer and the intermediate paint, the main components include high molecular polymers, pigments, solvents, and various additives. As the basic substance for forming the paint film, the proportion of the high molecular polymer in the formulation is crucial and usually needs to be controlled within the range of 30% to 50%, which can ensure that the final paint film has good elasticity and sufficient adhesion. Regarding the selection and proportion of the solvent, they must be carefully selected and adjusted according to the type of the high molecular polymer used and specific environmental requirements to ensure that the solvent content is within the range of 20% to 40%, which can effectively dissolve the high molecular polymer without causing too much impact on the environment.

[0042] In addition, to improve the performance of the paint, some additives are added, but the addition amount of these additives must be strictly controlled and shall not exceed 5% of the total formulation to avoid negative impacts on the performance of the paint film.

[0043] In one embodiment, physical vapor deposition technology is an advanced surface treatment method. It mainly deposits metal materials evenly on the surface of the colored material injection molded substrate by utilizing the high energy state of the plasma or by means of thermal evaporation. This technology can achieve precise control of the coating thickness. Generally, the thickness of the PVD coating is strictly controlled within the range of 50 to 100 nanometers to meet specific industrial standards and application requirements.

[0044] In addition, the coating thicknesses of the transparent UV protective paint and the UV topcoat also need to be precisely controlled, and are controlled between 10 and 20 microns and 20 and 30 microns respectively. Such thickness control is to ensure the uniformity of the paint film and sufficient protective effect, thereby extending the service life of the product and improving its appearance quality. During the coating process, UV curing technology is also used, which is a fast and efficient curing method. It cures the applied paint layer rapidly through ultraviolet irradiation, thereby improving production efficiency and ensuring the stability and durability of the paint layer.

[0045] In this embodiment, the entire electroplating process is carried out in a vacuum environment. This is done to ensure the uniformity and adhesion of the metal thin film, and at the same time can effectively reduce environmental pollution. After the PVD coating, we carried out surface treatment, which includes using ion implantation technology or chemical plating technology, aiming to further enhance the surface performance of the coating. To ensure the long-term stability and durability of the electroplating layer, after electroplating is completed, we carried out an aging test, which is to simulate the performance of the product in the actual use environment. According to the results of the aging test, we can optimize the electroplating process accordingly to ensure the quality and performance of the product.

[0046] In another embodiment of the present invention, to further enhance the appearance texture and durability of the product, a special surface treatment technology is adopted. This technology includes, after the PVD coating, using a PVD treatment agent to microstructurize the surface to form a surface with a specific pattern or texture. Such microstructuring can not only enhance the visual attractiveness of the product, but also improve the scratch resistance of the product to a certain extent. The microstructuring can be achieved by methods such as laser etching, chemical etching or mechanical grinding.

[0047] In yet another embodiment of the present invention, to meet the special requirements of different products for the performance of the electroplating layer, nanocomposites are introduced. The nanocomposites endow the electroplating layer with additional mechanical strength, chemical resistance and thermal stability by uniformly dispersing nanoparticles in a polymer matrix. The types of nanoparticles can be oxides, carbides or metal particles, etc., and their sizes are usually at the nanometer level to ensure uniform distribution in the polymer matrix.

[0048] The multi-color low-cost plastic vacuum electroplating process of the present invention also takes environmental protection factors into consideration. During the production process, the emissions of harmful substances are strictly controlled to ensure that the entire process meets environmental protection standards. For example, water-based coatings are used instead of traditional solvent-based coatings to reduce the emissions of volatile organic compounds (VOCs). In addition, compared with traditional wet electroplating, the vacuum electroplating technology itself can significantly reduce the generation of wastewater and waste residues, further reducing the impact on the environment.

[0049] In a further embodiment of the present invention, to improve production efficiency and reduce production costs, an automated production line is introduced. The automated production line can achieve fully automated operations from the preparation of the plastic substrate, surface treatment, primer coating, PVD plating, color intermediate coating to the coating of UV protective paint and UV topcoat. By precisely controlling the time and conditions of each step, the automated production line not only improves the consistency and repeatability of production, but also significantly reduces manual operations and labor costs.

[0050] In another embodiment of the present invention, to further enhance the weather resistance and corrosion resistance of the electroplated layer, a special surface treatment technology is adopted. This technology includes performing nano-level surface modification treatment on the surface after PVD plating to form a protective layer with high weather resistance and corrosion resistance. This nano-level surface modification treatment can be achieved by methods such as plasma treatment, chemical vapor deposition (CVD) or atomic layer deposition (ALD), thereby significantly improving the performance of the electroplated layer without increasing the additional thickness.

[0051] In a further embodiment of the present invention, to meet the special requirements of specific products for the electroplated layer, additives with specific functions are introduced. For example, to improve the antibacterial performance of the electroplated layer, an appropriate amount of antibacterial agents such as silver ions or copper ions can be added to the primer or intermediate paint. These antibacterial agents can effectively inhibit the growth of bacteria and microorganisms, thereby improving the hygienic safety of the product. In addition, to improve the self-cleaning ability of the electroplated layer, nanoparticles with superhydrophilic or superhydrophobic properties can be added to the UV protective paint, thereby endowing the product with self-cleaning function.

[0052] In another embodiment of the present invention, to achieve the personalization and diversification of the electroplated layer, digital printing technology is introduced. Through digital printing technology, various patterns and texts can be directly printed on the electroplated layer to meet the needs of personalized customization. The digital printing technology can be inkjet printing, thermal transfer printing or laser printing, etc. These technologies can precisely control the size, shape and color of the pattern to achieve high-precision and high-resolution printing effects.

[0053] In another embodiment of the present invention, to improve the adhesion and durability of the electroplated layer, a special primer treatment technology is adopted. This technology includes performing plasma treatment or ultraviolet irradiation treatment on the surface of the plastic substrate before applying Pramar primer to increase the surface roughness and activity. This pretreatment can significantly improve the adhesion between the primer and the plastic substrate, thereby improving the durability of the entire electroplated layer.

[0054] In yet another embodiment of the present invention, in order to improve the decorative and aesthetic properties of the electroplated layer, a special color intermediate paint treatment technology is adopted. This technology includes surface texturing the PVD coating before applying the color intermediate paint to form a texture with a metallic texture. This texturing treatment can be achieved by methods such as mechanical etching, chemical etching, or laser etching, thereby improving the decorative effect of the electroplated layer without increasing the extra thickness.

[0055] In yet another embodiment of the present invention, in order to improve the environmental protection performance of the electroplated layer, a special UV protective paint formulation is adopted. This formulation does not contain harmful organic solvents and heavy metals, but instead uses a water-based or solvent-free formulation to reduce the harm to the environment and operators. This environmentally friendly UV protective paint not only meets environmental protection standards but also provides a protection effect equivalent to that of traditional UV protective paints.

[0056] In yet another embodiment of the present invention, in order to improve the scratch resistance of the electroplated layer, a special surface hardening technology is adopted. This technology includes ion hardening treatment or ultraviolet hardening treatment of the surface after applying the UV topcoat to form a protective layer with high hardness and scratch resistance. This surface hardening treatment can significantly improve the scratch resistance of the electroplated layer, thereby extending the service life of the product.

[0057] In yet another embodiment of the present invention, in order to improve the heat resistance of the electroplated layer, a special heat stabilizer is adopted. This heat stabilizer can be added to the primer, intermediate paint, or topcoat to improve the stability of the electroplated layer in a high-temperature environment. This heat stabilizer can effectively prevent the electroplated layer from discoloring, softening, or peeling off at high temperatures, thereby improving the heat resistance of the product.

[0058] In yet another embodiment of the present invention, in order to improve the antistatic performance of the electroplated layer, a special antistatic agent is adopted. This antistatic agent can be added to the primer, intermediate paint, or topcoat to improve the antistatic performance of the electroplated layer. This antistatic agent can effectively prevent the electroplated layer from accumulating static electricity in a dry environment, thereby avoiding the influence of static electricity on the product performance.

[0059] In yet another embodiment of the present invention, in order to improve the UV resistance of the electroplated layer, a special UV absorber is adopted. This UV absorber can be added to the primer, intermediate paint, or topcoat to improve the UV resistance of the electroplated layer. This UV absorber can effectively absorb ultraviolet rays, prevent ultraviolet rays from damaging the electroplated layer, thereby extending the service life of the product.

[0060] The multi-color low-cost plastic vacuum electroplating process provided by the present invention, through the application of a series of innovative technologies, not only improves the quality and production efficiency of products, but also significantly reduces the production cost. The implementation of this process provides more possibilities for the appearance design of 3C products and other plastic products, and promotes the development and application of plastic vacuum electroplating technology.

[0061] In summary, referring to Figure 3 and Figure 4 as shown, the multi-color low-cost plastic vacuum plating technology involved in the present invention realizes the innovation of the two-color or multi-color NCVM (plastic vacuum plating) process by effectively combining colored plastics with color coatings and through the method of process superposition. This technology has brought new breakthroughs to the appearance process of 3C products. Compared with the single-color treatment method of five coatings and five bakings used in the traditional NCVM (plastic vacuum plating) process, the new low-cost plastic vacuum plating process of the present invention reduces the single-color NCVM process to three or four coatings through the optimization of materials and coatings. At the same time, the two-color NCVM process is simplified from eight coatings and eight bakings to six coatings and six bakings, and is superior to the traditional process in terms of color richness, cost control, production process simplification, and yield improvement (refer to Figure 1 and Figure 2 as shown).

[0062] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements for some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A multi-color low-cost plastic vacuum electroplating process, characterized in that, Including the following steps: Surface-treat the colored material injection-molded substrate to ensure good adhesion between the coating and the plastic substrate, and set a Pramar base on it; Apply a color primer on the Pramar base and form a metal thin film PVD coating through physical vapor deposition technology; Apply a color intermediate coat and a transparent UV protective paint on the PVD coating, and form another metal thin film PVD coating through physical vapor deposition technology again; Select a suitable color intermediate coat to apply on the new PVD coating, and at the same time apply a transparent UV topcoat on the outermost layer. After the paint dries, the finished product is obtained.

2. A multi-color low-cost plastic vacuum electroplating process according to claim 1, characterized in that, In the said method, the colored material injection-molded substrate is ABS plastic. When the colored material injection-molded substrate is surface-treated, sandblasting or chemical etching methods are used to remove the oil stains and impurities on the surface to ensure good adhesion between the coating and the substrate.

3. A multi-color low-cost plastic vacuum electroplating process according to claim 1, characterized in that, In the said method, the Pramar base material is acrylic resin, which is used to provide adhesion and plays a protective role in the subsequent PVD coating process to prevent adverse reactions caused by direct contact between the metal thin film and the plastic substrate. The coating thickness of the Pramar base is controlled between 10 - 20 microns to ensure its uniformity and sufficient covering power.

4. A multi-color low-cost plastic vacuum electroplating process according to claim 1, characterized in that, In the said method, the color primer and the intermediate coat are composed of a polymer, pigments, solvents, and various additives. Among them, the polymer is used as the film-forming substance, and its proportion is controlled between 30% - 50% to ensure the elasticity and adhesion of the paint film. The type and proportion of the solvent are selected according to the type of the polymer used and environmental requirements, and are controlled within the range of 20% - 40%. The addition amount of the additives does not exceed 5%.

5. A multi-color low-cost plastic vacuum electroplating process according to claim 1, characterized in that, In the said method, physical vapor deposition technology uses plasma or thermal evaporation to deposit metal materials onto the colored material injection-molded substrate.

6. A multicolor low-cost plastic vacuum electroplating process according to claim 1, characterized in that In the said method, the thickness of the PVD coating is controlled between 50 - 100 nanometers.

7. A multi-color low-cost plastic vacuum electroplating process according to claim 1, characterized in that, In the said method, the coating thicknesses of the transparent UV protective paint and the UV topcoat are respectively controlled between 10 - 20 microns and 20 - 30 microns to ensure the uniformity of the paint film and sufficient protective effect, and at the same time use the UV curing technology for the applied paint layer.

8. A multi-color low-cost plastic vacuum electroplating process according to claim 1, characterized in that, In the said method, the entire electroplating process is carried out in a vacuum environment to ensure the uniformity and adhesion of the metal thin film, and at the same time reduce environmental pollution.

9. A multi-color low-cost plastic vacuum electroplating process according to claim 1, characterized in that, In the said method, surface treatment is carried out after the PVD coating, using ion implantation technology or chemical plating technology to enhance the surface performance of the coating.

10. A multi-color low-cost plastic vacuum electroplating process according to claim 1, characterized in that, In the said method, in order to ensure the long-term stability and durability of the electroplated layer, an aging test is carried out after electroplating to simulate the performance of the product in the actual use environment, and the electroplating process is optimized according to the test results.

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