Vacuum plating processing technology and method for plastic lamination

Abstract

According to the vacuum plating processing technology and method for plastic lamination, the back face of the plastic base material is evenly coated with the semitransparent primer, the adhesive force and binding force between a vacuum plating layer and the base material are enhanced, it is guaranteed that the plating layer is not prone to falling off or blistering in long-term use, and the service life of the plating layer is prolonged. Chrome plating layer colored paint or aluminum plating layer colored paint used in the vacuum plating process is light-proof black paint, the light leakage phenomenon is effectively prevented, the semitransparent primer layer is arranged between the vacuum plating layer and the plastic base material and used for enhancing the adhesive force and binding force between the vacuum plating layer and the base material, the high-temperature and high-humidity environment is resisted, and the service life of the vacuum plating layer is prolonged. The back protective paint is added on the back, so that the bonding reliability after gluing is improved, the impression of the glue layer caused by a high-temperature and high-humidity environment is eliminated, and the problem that in the prior art, after a part is bonded on the surface of an electronic part, the glue trace is displayed and cannot be eliminated due to long time or high-temperature exposure of a vehicle is solved.

Description

Technical Field

[0001] The invention relates to the technical field of automobile parts processing, and in particular to a vacuum electroplating processing technology and method for plastic bonding. Background Art

[0002] With the development of the automobile industry, the colors of automobile interiors are becoming more and more diverse. Due to environmental protection requirements, electroplating processes that are more harmful to the environment are gradually being eliminated, and vacuum electroplating processes are replacing them. Vacuum electroplating (PVD, physical vapor deposition) is a physical vapor deposition process that uses physical methods to vaporize the surface of the source material (solid or liquid) into gaseous atoms or molecules, or partially ionize them into ions under vacuum conditions, and deposits a thin film or coating with some special functions on the collective surface through a low-pressure gas (or plasma) process. The color of the film or coating can be adjusted by changing the source material, making the color more diverse and rich. Compared with traditional electroplating processes, it is more environmentally friendly and pollution-free.

[0003] In the manufacture of automotive electronic components, vacuum plating processes are often used for surface treatment of parts so that they can be pasted on the surface of automotive electronic components as decorative appearance parts. However, the existing vacuum plating processes have some significant problems.

[0004] The vacuum plating process method shown in patent CN116949393A has exposed many defects in actual use after the manufactured parts are pasted on the surface of electronic components. On the one hand, after long-term use or when the vehicle is exposed to high temperature, the surface of the parts will show glue marks that are difficult to remove, seriously affecting the appearance quality of the product. On the other hand, the vacuum plating layer in this process method has insufficient adhesion and bonding strength with the substrate, and it is difficult to resist the high temperature and high humidity environment, which easily causes the coating to fall off or be damaged, reducing the service life and reliability of the parts.

[0005] In addition, the existing process is not effective in improving the wear resistance of the surface of parts and cannot effectively protect the substrate. At the same time, there are also deficiencies in the display effect, which makes it difficult to meet the high requirements of automotive electronic components for decorative appearance parts.

[0006] In summary, the existing vacuum plating process has many shortcomings in terms of glue traces, coating adhesion and bonding, substrate protection, wear resistance and display effect, and new and improved vacuum plating processing technology and methods for plastic bonding are urgently needed to solve these problems. Therefore, we make improvements and propose a vacuum plating processing technology and method for plastic bonding. Summary of the invention

[0007] The purpose of the present invention is to solve the problems in the existing background technology. In order to achieve the above invention purpose, the present invention provides the following technical solutions: a vacuum plating process for plastic bonding, comprising the following steps:

[0008] S1. Material preparation: select transparent plastic substrate and front protective paint and prepare translucent primer, select vacuum plating coating material, prepare topcoat and back protective paint;

[0009] S2. Applying front protective paint: Applying the front protective paint on the front of the plastic substrate by spraying or brushing, and using ultraviolet equipment to cure the applied front protective paint to form a paint film with high hardness and high gloss;

[0010] S3, applying translucent primer: evenly applying translucent primer on the back of the plastic substrate, and performing high-temperature drying on the back of the plastic substrate coated with the translucent primer;

[0011] S4, vacuum plating: placing the plastic substrate coated with the translucent primer into the vacuum plating equipment for vacuum plating treatment;

[0012] S5. Apply topcoat: Apply topcoat to the outer surface after vacuum plating by spraying or brushing;

[0013] S6. Apply back protective paint: Apply back protective paint on the outer surface of the topcoat and printing ink.

[0014] As a preferred technical solution of the present invention, S1, material preparation: the plastic substrate adopts a transparent plastic substrate, and the transparent plastic substrate includes PMMA (acrylic) and PC (polycarbonate) transparent substrates.

[0015] As the preferred technical solution of the present invention, S2, applying front protective paint: the front protective paint is UV paint, with a thickness of 10um-50um, ultraviolet-cured paint, and the raw material used is epoxy resin. The paint film has high hardness and high gloss, and is used to protect the substrate and improve the wear resistance of the part surface.

[0016] As a preferred technical solution of the present invention, S3, applying a translucent primer, the thickness of the translucent primer is 10-60um, which is used to enhance the adhesion and bonding force between the vacuum electroplated coating and the substrate and resist high temperature and high humidity environment.

[0017] As a preferred technical solution of the present invention, S4, vacuum plating, the plating thickness of the vacuum plating is 0.1um-15um, the coating of the vacuum plating is a chrome-plated layer paint or an aluminum-plated layer paint, the coating thickness of the vacuum plating is 20-50um, and the coating of the vacuum plating is an opaque black paint to prevent light leakage.

[0018] As a preferred technical solution of the present invention, S6, apply a back protective paint, the back protective paint is UV paint or PU paint, the back protective paint has a thickness of 10um-50um, the film forming method is natural film forming, the paint film is thin and not very hard, but its adhesion is particularly good, its gloss is even, it does not look very bright, and it can have a good display effect. At the same time, it can increase the bonding reliability after gluing and eliminate the visible marks of the glue layer caused by high temperature and high humidity environment.

[0019] A vacuum electroplating processing method for plastic bonding, comprising the following method steps: Step 1: applying a front protective paint on the front of a plastic substrate by spraying or brushing, and then curing the applied front protective paint by using an ultraviolet device to form a paint film with high hardness and high gloss;

[0020] Step 2: Evenly apply a translucent primer on the back of the plastic substrate, and then dry the back of the plastic substrate coated with the translucent primer at a high temperature;

[0021] Step 3: Place the plastic substrate coated with the translucent primer into the vacuum plating equipment for vacuum plating with a plating thickness of 0.1um-15um;

[0022] Step 4: Apply topcoat to the outer surface after vacuum plating by spraying or brushing;

[0023] Step 5: Laser engraving symbols: Carve away the translucent primer, vacuum plating layer, and topcoat to engrave the desired display symbols. The symbol color is the color of the plastic substrate.

[0024] Step 6: Printing ink: Print a light-transmitting ink layer on top of the symbol. The ink color is printed according to the display requirements of the symbol.

[0025] Step 7: Apply back protective paint on the outer surface of the topcoat and printing ink;

[0026] Step 8: An LED light source is arranged on the rear side of the back protective paint. The light of the LED can pass through the back protective paint, printing ink, and be displayed through the plastic substrate and the front protective paint.

[0027] As a preferred technical solution of the present invention, step 5: laser engraving symbol specific steps are as follows:

[0028] Step 51: Prepare the laser engraving equipment, fix the workpiece that has been treated with translucent primer, vacuum plating and topcoat on the workbench of the laser engraving equipment, ensure that the workpiece is stable and accurately positioned, and import the relevant graphic data into the control system of the laser engraving equipment according to the symbol design to be displayed;

[0029] Step 52: Set the parameters of laser engraving, including laser power set to 50W-60W, engraving speed 0-85mm / min, and repeat positioning accuracy: ±0.1mm;

[0030] Step 53: Start the laser engraving device and start the engraving operation; the laser beam will accurately engrave the translucent primer, vacuum plating layer and topcoat on the surface of the workpiece according to the preset graphic data, thereby displaying the required symbols;

[0031] Step 54: After engraving, carefully check the quality of the symbol. The color of the symbol should be the color of the plastic substrate, that is, transparent. Check whether the symbol is complete and clear, whether the edges are neat, and whether there is any residual primer, coating or topcoat.

[0032] Step 55: Clean the engraved workpiece to remove the debris and debris generated during the engraving process.

[0033] As a preferred technical solution of the present invention, step 6: printing ink, the specific steps are as follows:

[0034] Step 61: Prepare ink that meets the requirements for symbol display, place the workpiece after laser engraving the symbol on the printing device, ensure the position of the workpiece is accurate, and use the printing device to print ink above the symbol;

[0035] Step 62: Adjust the parameters of the printing equipment, including printing pressure and speed, to control the output of ink. Printing pressure: The printing pressure is set at 10N / cm 2 -30N / cm 2 The printing speed is set between 100mm / s-500mm / s; the ink output is 0.5g / m 2 -2g / m 2 between;

[0036] Step 63: The thickness of the printed ink layer is between 1um and 20um, and the ink color is selected for printing according to the display of the symbol.

[0037] As a preferred technical solution of the present invention, step 8: an LED light source with a diameter of 2mm-6mm and a power of 0.2W-1.6W is arranged on the back side of the back protective paint.

[0038] Compared with the prior art, the present invention has the following beneficial effects:

[0039] In the scheme of the present invention, a translucent primer layer is provided between the vacuum electroplating layer and the plastic substrate to enhance the adhesion and bonding force between the vacuum electroplating layer and the substrate and resist high temperature and high humidity environment.

[0040] Adding a back protective paint on the back side can increase the bonding reliability after gluing and eliminate the visible marks of the glue layer caused by high temperature and high humidity environment. This solves the problem in the prior art that after parts are pasted on the surface of electronic components, glue marks are shown due to a long time or high temperature exposure of the vehicle and cannot be eliminated, thereby improving the quality and reliability of the product.

[0041] By applying UV paint on the front side of the plastic substrate as a front protective paint, a paint film with high hardness and high gloss is formed, which significantly improves the wear resistance of the part surface. This helps to extend the service life of the product and reduce appearance and functional problems caused by wear.

[0042] By evenly coating the back of the plastic substrate with a semi-transparent primer, the adhesion and bonding between the vacuum plating layer and the substrate are enhanced, ensuring that the plating layer is not easy to fall off or bubble during long-term use, thereby improving the reliability and stability of the product. The chrome plating layer paint or aluminum plating layer paint used in the vacuum plating process is an opaque black paint, which effectively prevents the occurrence of light leakage.

[0043] The back protective paint adopts a natural film-forming method. The paint film is thin but has particularly good adhesion. Its gloss is even and not too bright, so that when the LED light passes through, it can present a clear and bright symbol display effect, enhancing the visual effect and appeal of the product. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Figure 1 The logic block diagram of the backlight-free process provided by the present invention;

[0045] Figure 2 The present invention provides a backlight process logic block diagram;

[0046] Figure 3 This is an experimental data diagram provided by the present invention. DETAILED DESCRIPTION

[0047] To make the purpose, technical solution and advantages of the embodiment of the present invention clearer, the technical solution in the embodiment of the present invention will be clearly and completely described below in conjunction with the accompanying drawings. Obviously, the described embodiment is a specific implementation of the present invention and is not limited to all embodiments.

[0048] Therefore, the following detailed description of the embodiments of the present invention is not intended to limit the scope of the invention claimed for protection, but merely represents some embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0049] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features and technical solutions therein can be combined with each other. It should be noted that similar numbers and letters represent similar items in the following drawings. Therefore, once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings.

[0050] Example 1: Please refer to Figure 1 ,A vacuum electroplating process for plastic lamination ,without backlight process includes the following steps,S1, material preparation: selecting transparent plastic substrate and front side protective paint and preparing translucent primer, selecting the coating material for vacuum electroplating, preparing top paint and back side protective paint;

[0051] S2. Applying front protective paint: Applying the front protective paint on the front of the plastic substrate by spraying or brushing, and using ultraviolet equipment to cure the applied front protective paint to form a paint film with high hardness and high gloss;

[0052] S3, applying translucent primer: evenly applying translucent primer on the back of the plastic substrate, and performing high-temperature drying on the back of the plastic substrate coated with the translucent primer;

[0053] S4, vacuum plating: placing the plastic substrate coated with the translucent primer into the vacuum plating equipment for vacuum plating treatment;

[0054] S5. Apply topcoat: Apply topcoat to the outer surface after vacuum plating by spraying or brushing;

[0055] S6. Apply back protective paint: Apply back protective paint on the outer surface of the topcoat and printing ink.

[0056] S1. Material preparation: The plastic substrate adopts a transparent plastic substrate, and the transparent plastic substrate includes PMMA (acrylic) and PC (polycarbonate) transparent substrate.

[0057] S2. Apply front protective paint: The front protective paint is UV paint, with a thickness of 10um-50um, and is a UV-cured paint. The raw material used is epoxy resin, and the paint film has high hardness and high gloss. It is used to protect the substrate and improve the wear resistance of the part surface.

[0058] S3, apply a translucent primer, the thickness of which is 10-60 um, to enhance the adhesion and bonding force between the vacuum-plated coating and the substrate and to resist high temperature and high humidity environments.

[0059] S4, vacuum plating, the vacuum plating thickness is 0.1um-15um, the vacuum plating layer is chrome plating paint or aluminum plating paint, the vacuum plating layer thickness is 20-50um, the vacuum plating layer is opaque black paint to prevent light leakage.

[0060] S6. Apply a back protective paint, which is UV paint or PU paint. The thickness of the back protective paint is 10um-50um. The film forming method is natural film forming. The paint film is thin and not very hard, but its adhesion is particularly good. Its gloss is even and does not look very bright. It can have a good display effect and can increase the bonding reliability after gluing, eliminating the visible marks of the glue layer caused by high temperature and high humidity environment.

[0061] Example 2: Please refer to Figure 2 , a vacuum electroplating processing method for plastic bonding, a backlight process method comprising the following method steps: Step 1: applying a front protective paint on the front of the plastic substrate by spraying or brushing, and then using an ultraviolet device to cure the applied front protective paint to form a paint film with high hardness and high gloss;

[0062] Step 2: Evenly apply a translucent primer on the back of the plastic substrate, and then dry the back of the plastic substrate coated with the translucent primer at a high temperature;

[0063] Step 3: Place the plastic substrate coated with the translucent primer into the vacuum plating equipment for vacuum plating with a plating thickness of 0.1um-15um;

[0064] Step 4: Apply topcoat to the outer surface after vacuum plating by spraying or brushing;

[0065] Step 5: Laser engraving symbols: Carve away the translucent primer, vacuum plating layer, and topcoat to engrave the desired display symbols. The symbol color is the color of the plastic substrate.

[0066] Step 6: Printing ink: Print a light-transmitting ink layer on top of the symbol. The ink color is printed according to the display requirements of the symbol.

[0067] Step 7: Apply back protective paint on the outer surface of the topcoat and printing ink;

[0068] Step 8: An LED light source is arranged on the rear side of the back protective paint. The light of the LED can pass through the back protective paint, printing ink, and be displayed through the plastic substrate and the front protective paint.

[0069] Step 5: Laser engraving symbol specific steps are as follows:

[0070] Step 51: Prepare the laser engraving equipment, fix the workpiece that has been treated with translucent primer, vacuum plating and topcoat on the workbench of the laser engraving equipment, ensure that the workpiece is stable and accurately positioned, and import the relevant graphic data into the control system of the laser engraving equipment according to the symbol design to be displayed;

[0071] Step 52: Set the parameters of laser engraving, including laser power set to 50W-60W, engraving speed 0-85mm / min, and repeat positioning accuracy: ±0.1mm;

[0072] Step 53: Start the laser engraving device and start the engraving operation; the laser beam will accurately engrave the translucent primer, vacuum plating layer and topcoat on the surface of the workpiece according to the preset graphic data, thereby displaying the required symbols;

[0073] Step 54: After engraving, carefully check the quality of the symbol. The color of the symbol should be the color of the plastic substrate, that is, transparent. Check whether the symbol is complete and clear, whether the edges are neat, and whether there is any residual primer, coating or topcoat.

[0074] Step 55: Clean the engraved workpiece to remove the debris and debris generated during the engraving process.

[0075] Step 6: Printing ink The specific steps are as follows:

[0076] Step 61: Prepare ink that meets the requirements for symbol display, place the workpiece after laser engraving the symbol on the printing device, ensure the position of the workpiece is accurate, and use the printing device to print ink above the symbol;

[0077] Step 62: Adjust the parameters of the printing equipment, including printing pressure and speed, to control the output of ink. Printing pressure: The printing pressure is set at 10N / cm 2 -30N / cm 2 The printing speed is set between 100mm / s-500mm / s; the ink output is 0.5g / m 2 -2g / m 2 between;

[0078] Step 63: The thickness of the printed ink layer is between 1um and 20um, and the ink color is selected for printing according to the display of the symbol.

[0079] Front protection paint, UV paint, thickness 10um-50um, UV-cured paint, raw material is epoxy resin, paint film has high hardness and high gloss, used to protect the substrate and improve the wear resistance of the parts surface;

[0080] Plastic substrate, a transparent plastic substrate is used. In the present invention, PMMA (acrylic) is used. PC (polycarbonate) transparent substrate can also be selected;

[0081] Translucent primer, thickness 10-60um, used to enhance the adhesion and bonding between the vacuum electroplated coating and the substrate, and resist high temperature and high humidity environment;

[0082] Vacuum plating, thickness 0.1-15um, chrome plating or aluminum plating color paint, thickness 20-50um, opaque black paint to prevent light leakage;

[0083] The back protective paint can be UV paint or PU paint with a thickness of 10um-50um. The case of the present invention uses PU paint, which is a general term for polyester paint. The film forming method is natural film forming, and no special process is required. Its characteristics are: the paint film is thin and not very hard, but its adhesion is particularly good, its gloss is even, it does not look very bright, and it can have a good display effect. At the same time, it can increase the bonding reliability after gluing and eliminate the visible marks of the glue layer caused by high temperature and high humidity environment.

[0084] Laser engraving symbols, engrave the translucent primer, vacuum plating layer, and topcoat to engrave the required display symbols. At this time, the symbol color is the color of the plastic substrate, that is, transparent color;

[0085] Printing ink, a light-transmitting ink layer is printed on the top of the symbol, with a thickness of 1-20um. The ink color is printed according to the display requirements of the symbol. The case of the present invention uses white oil-exposure LED light to pass through the back protective paint, printing ink, and through the plastic substrate and the front protective paint to be displayed.

[0086] Enhanced adhesion and bonding: By setting a translucent primer layer between the vacuum electroplating layer and the plastic substrate, the adhesion and bonding between the vacuum electroplating layer and the substrate are significantly enhanced, which can effectively resist high temperature and high humidity environment and avoid the coating from falling off or being damaged.

[0087] Improve bonding reliability: Adding a back protective paint on the back of the part, such as the PU paint selected in the present invention, has particularly good adhesion and can increase the bonding reliability after gluing. At the same time, the protective paint can eliminate the impression of the glue layer caused by high temperature and high humidity environment, ensuring the integrity and beauty of the appearance of the part.

[0088] Protect the substrate and improve wear resistance: Use positive protective paint (UV paint) with a thickness of 10um-50um. Its raw material is epoxy resin, and the paint film has high hardness and high gloss. This protective paint can effectively protect the substrate, improve the wear resistance of the part surface, and extend the service life of the parts.

[0089] Adaptable to a variety of substrates: Plastic substrates can be selected from transparent PMMA (acrylic) or PC (polycarbonate) transparent substrates, providing more options for design and application.

[0090] By using a translucent primer with a thickness of 10-60um, it not only helps to enhance adhesion, but also allows the engraved symbols to present the transparent color of the plastic substrate when the laser engraving symbols. Then a layer of translucent ink is printed on the top of the symbol. The ink color can be printed according to the display requirements of the symbol, such as the white ink used in the case of the present invention. This design allows the light of the LED to pass through the back protective paint, printing ink, through the plastic substrate and the front protective paint to be displayed, achieving a good display effect.

[0091] The present invention solves the problem that after the parts are pasted on the surface of electronic components, glue marks appear and cannot be removed due to a long time or high temperature exposure of the vehicle, thereby improving the quality and reliability of the product.

[0092] Example 3, please refer to Figure 1 , a vacuum plating process for plastic bonding, select the following materials: Select transparent PMMA (acrylic) as the plastic substrate. Prepare a translucent primer with a thickness of 30um. Vacuum plating material is used to form a coating. In this embodiment, a chrome plating layer is selected with a thickness of 5um. For color paint, an opaque black paint is selected with a thickness of 30um. PU paint is selected as the back protective paint with a thickness of 30um. White ink for printing symbols with a thickness of 10um. UV paint is selected as the front protective paint with a thickness of 30um.

[0093] Apply translucent primer: Clean the PMMA plastic substrate to remove dust and impurities on the surface. Use coating equipment to evenly apply the translucent primer on the plastic substrate, ensuring that the thickness of the primer reaches 30um. Put the substrate coated with primer into the oven and dry it at an appropriate temperature to enhance the adhesion between the primer and the substrate.

[0094] Vacuum plating: Place the substrate coated with primer into the vacuum plating equipment. Under vacuum conditions, the chrome plating material is heated and evaporated to form gaseous atoms or molecules, which are deposited on the surface of the substrate to form a chrome plating layer with a thickness of 5um.

[0095] Applying color paint: After vacuum plating is completed, take out the substrate and cool it to room temperature. Use coating equipment to evenly apply black paint on the chrome-plated layer, ensuring that the thickness of the paint reaches 30um. Put the substrate coated with color paint into the oven again for drying.

[0096] Apply back protective paint: After the color paint is dried, take out the substrate and apply PU paint on its back with a thickness of 30um. Let the PU paint form a film naturally without special process.

[0097] Applying front protective paint: After the ink is printed, UV paint is applied on the front of the substrate with a thickness of 30um. Use ultraviolet irradiation equipment to cure the UV paint to form a paint film with high hardness and high gloss to protect the substrate and improve the wear resistance of the part surface.

[0098] Through the specific implementation methods of the above embodiments, a vacuum electroplating process for plastic bonding can be realized, which can effectively avoid the problem of glue marks in actual use, while making the product have more diversified and rich colors, and more environmentally friendly and pollution-free.

[0099] Example 4, please refer to Figure 2 , a vacuum plating processing method for plastic bonding, prepare the following materials: select PC (polycarbonate) as the transparent plastic substrate. Translucent primer, thickness is 40um. Vacuum plating material is aluminum plating layer, thickness is 8um. Color paint is black paint, thickness is 40um. Back protective paint is UV paint, thickness is 40um. Printing ink is blue ink, thickness is 15um. Front protective paint is UV paint, thickness is 40um.

[0100] Apply translucent primer: Clean the PC plastic substrate to ensure a clean surface. Use a coating device to evenly apply the translucent primer on the substrate to a thickness of 40um. Place the substrate coated with primer in a drying device and dry it at a suitable temperature.

[0101] Vacuum plating: Place the substrate coated with primer into the vacuum plating equipment. In a vacuum environment, the aluminum material is heated and vaporized, and deposited on the surface of the substrate in the form of gaseous atoms or molecules to form an 8um thick aluminum plating layer.

[0102] Coating color paint: After vacuum plating, take out the substrate and cool it. Use coating equipment to evenly coat the black paint on the aluminum layer with a thickness of 40um. Put the substrate coated with color paint into the oven for drying.

[0103] Apply back protective paint: After the color paint is dried, take out the substrate and apply UV paint on the back with a thickness of 40um.

[0104] Use ultraviolet rays to cure UV paint to form a protective film.

[0105] Laser engraving symbols: Using laser engraving technology, the translucent primer, vacuum plating layer and color paint are engraved according to the design requirements to form the required display symbols. The color of the symbols is the color of the plastic substrate.

[0106] Printing ink: On top of the engraved symbols, use a printing device to print a layer of blue ink with a thickness of 15um.

[0107] Applying front protective paint: After the ink is printed, UV paint is applied on the front of the substrate with a thickness of 40um. The UV paint is cured by ultraviolet light to form a solid paint film, which plays a role in protecting the substrate and improving the surface performance.

[0108] Apply front protective paint: Apply front protective paint (UV paint) on the front of the plastic substrate by spraying or brushing, with a thickness of 10um-50um. Use ultraviolet equipment to cure the applied front protective paint to form a paint film with high hardness and glossiness to protect the substrate and improve the wear resistance of the part surface.

[0109] Apply translucent primer: Evenly apply translucent primer on the back of the plastic substrate, with the thickness controlled between 10-60um. Ensure that the primer is fully dried to enhance the adhesion and bonding between the vacuum plating layer and the substrate, and improve the stability of the product in high temperature and high humidity environments.

[0110] Vacuum plating: Place the plastic substrate coated with translucent primer into the vacuum plating equipment for vacuum plating. Select chrome plating paint or aluminum plating paint as the plating material, control the plating thickness between 0.1um-15um, and the plating thickness is 20-50um.

[0111] Make sure the coating is even, dense, and opaque black paint to prevent light leakage.

[0112] Apply topcoat: Apply topcoat to the outer surface after vacuum plating by spraying or brushing to improve the appearance quality and corrosion resistance of the product. Ensure that the topcoat is fully dried to form a uniform and smooth paint film.

[0113] Setting printing ink: Setting printing ink on the outer surface of the topcoat by printing. Ensure that the pattern of the printing ink is clear, accurate and bright in color.

[0114] Laser engraving symbols: Use laser engraving equipment to engrave the desired symbols on the printing ink. Control the parameters of laser engraving to ensure the clarity and accuracy of the symbols.

[0115] Apply back protective paint: Apply back protective paint (UV paint or PU paint) on the outer surface of the topcoat and printing ink, and the thickness is controlled between 10um-50um.

[0116] Experimental example

[0117] Purpose:

[0118] 1. Verify whether the new process can eliminate the glue mark problem.

[0119] 2. Test whether the adhesion and bonding strength of the coating are enhanced in the new process.

[0120] 3. Check whether the new process can improve the wear resistance of the part surface.

[0121] 4. Evaluate whether the display effect of the new process meets the requirements.

[0122] Experimental Materials:

[0123] PMMA (acrylic) transparent plastic substrate; translucent primer; vacuum plating layer (chrome plating layer); front protective paint (UV paint); back protective paint (PU paint); light-transmitting ink;

[0124] Experimental steps:

[0125] Step 1. Prepare PMMA transparent plastic substrate and clean the surface.

[0126] Step 2. Apply a 10-60um thick translucent primer layer on the PMMA substrate, and perform vacuum plating after curing to form a 0.1-15um thick chrome plating layer.

[0127] Step 3. Apply 20-50um thick opaque black paint on the chrome plating layer to prevent light leakage.

[0128] Step 4. Apply 10um-50um thick PU paint on the back of the part as back protective paint.

[0129] Step 5. Use a laser engraving machine to engrave the desired symbols on the surface of the part to reveal the color of the PMMA substrate.

[0130] Step 6. Print a 1-20um thick layer of white light-transmitting ink on top of the engraved symbols.

[0131] Step 7. After completing the above steps, the parts are subjected to aging tests in high temperature and high humidity environments, as well as wear resistance tests and display effect evaluations.

[0132] Experimental data

[0133]

[0134]

[0135] Experimental analysis

[0136] 1. Glue trace problem:

[0137] The traditional process will show obvious glue marks after being exposed to high temperature, which seriously affects the appearance quality of the product.

[0138] The new process effectively eliminates glue marks caused by high temperature and high humidity environments by adding PU paint as a protective layer on the back of the part, thereby maintaining the appearance integrity and aesthetics of the part.

[0139] 2. Coating adhesion:

[0140] The coating adhesion of the traditional process is low, only 5N / mm 2 , it is easy to fall off or be damaged in high temperature and high humidity environment.

[0141] The new process significantly enhances the adhesion of the coating to 6.5N / mm by placing a translucent primer layer between the vacuum plating layer and the plastic substrate. 2 , increased by 30%, effectively resisting the influence of high temperature and high humidity environment.

[0142] 3. Wear resistance:

[0143] The wear resistance of traditional technology is poor, and the wear resistance is only 1,000 times, which limits the service life of the product.

[0144] The new process uses UV paint as the front protective paint, which improves the wear resistance of the part surface, increases the number of wear times to 1,200 times, and extends the service life by at least 20%.

[0145] 4. Display effect:

[0146] The traditional technology has poor display effects, with symbols not being clear enough and colors not being bright enough.

[0147] The new process uses a translucent primer and translucent ink design, which allows the LED light to pass through the back protective paint, printing ink, through the plastic substrate and the front protective paint to show up, achieving a good display effect with clear and visible symbols and bright colors.

[0148] Conclusion: The vacuum electroplating process and method for plastic bonding proposed in this invention successfully solves several key problems in the existing process, including glue traces, insufficient coating adhesion, poor wear resistance and poor display effect. Through experimental verification, the new process significantly improves the quality and reliability of the product.

[0149] Specifically:

[0150] The glue marks after high temperature exposure are completely eliminated, maintaining the appearance integrity and beauty of the parts.

[0151] The adhesion of the coating is significantly enhanced by 30%, effectively resisting the influence of high temperature and high humidity environment.

[0152] Improves the wear resistance of parts surface and prolongs service life by at least 20%.

[0153] A good display effect is achieved, symbols are clearly visible, and colors are bright, meeting the high requirements of automotive electronic components for decorative appearance.

[0154] In summary, the vacuum electroplating processing technology and method for plastic bonding proposed in the present invention successfully solves the problems of glue traces, insufficient coating adhesion, poor wear resistance and poor display effects in the existing process, and significantly improves the quality and reliability of the product.

[0155] The above embodiments are only used to illustrate the present invention and are not intended to limit the technical solutions described in the present invention. Although the present invention has been described in detail with reference to the above embodiments, the present invention is not limited to the above specific implementation methods. Therefore, any modification or replacement of the present invention; and all technical solutions and improvements thereof that do not depart from the spirit and scope of the invention are included in the scope of the claims of the present invention.

Claims

1. A vacuum plating process for plastic bonding, characterized in that: The following steps are involved: S1. Material preparation: select transparent plastic substrate and front protective paint and prepare translucent primer, select vacuum plating coating material, prepare topcoat and back protective paint; S2. Applying front protective paint: Applying the front protective paint on the front of the plastic substrate by spraying or brushing, and using ultraviolet equipment to cure the applied front protective paint to form a paint film with high hardness and high gloss; S3, applying translucent primer: evenly applying translucent primer on the back of the plastic substrate, and performing high-temperature drying on the back of the plastic substrate coated with the translucent primer; S4, vacuum plating: placing the plastic substrate coated with the translucent primer into the vacuum plating equipment for vacuum plating treatment; S5. Apply topcoat: Apply topcoat to the outer surface after vacuum plating by spraying or brushing; S6. Apply back protective paint: Apply back protective paint on the outer surface of the topcoat and printing ink.

2. A vacuum plating process for plastic bonding according to claim 1, characterized in that: S1. Material preparation: The plastic substrate adopts a transparent plastic substrate, and the transparent plastic substrate includes PMMA (acrylic) and PC (polycarbonate) transparent substrate.

3. The vacuum plating process for plastic bonding according to claim 1, characterized in that: S2. Applying front protective paint: The thickness of the front protective paint UV paint is 10um-50um. The front protective paint adopts ultraviolet curing paint, and the raw material adopts epoxy resin.

4. The vacuum plating process for plastic bonding according to claim 1, characterized in that: S3, apply translucent primer, the thickness of the translucent primer is 10-60um.

5. The vacuum plating process for plastic bonding according to claim 1, characterized in that: S4, vacuum plating, the vacuum plating plating thickness is 0.1um-15um, the vacuum plating coating is chrome plating paint or aluminum plating paint, the vacuum plating coating thickness is 20-50um, and the vacuum plating coating is opaque black paint.

6. The vacuum plating process for plastic bonding according to claim 1, characterized in that: S6. Apply a back protective paint, wherein the back protective paint is UV paint or PU paint, the thickness of the back protective paint is 10um-50um, and the film forming method is natural film forming.

7. A vacuum electroplating method for plastic bonding, characterized in that: The method comprises the following steps: Step 1: applying a front protective paint on the front of the plastic substrate by spraying or brushing, and then curing the applied front protective paint by using an ultraviolet device to form a paint film with high hardness and high gloss; Step 2: Evenly apply a translucent primer on the back of the plastic substrate, and then dry the back of the plastic substrate coated with the translucent primer at a high temperature; Step 3: Place the plastic substrate coated with the translucent primer into the vacuum plating equipment for vacuum plating with a plating thickness of 0.1um-15um; Step 4: Apply topcoat to the outer surface after vacuum plating by spraying or brushing; Step 5: Laser engraving symbols: Carve away the translucent primer, vacuum plating layer, and topcoat to engrave the desired display symbols. The symbol color is the color of the plastic substrate. Step 6: Printing ink: Print a light-transmitting ink layer on top of the symbol, and the ink color is printed according to the display of the symbol; Step 7: Apply back protective paint on the outer surface of the topcoat and printing ink; Step 8: An LED light source is arranged on the rear side of the back protective paint, and the light of the LED is transmitted through the back protective paint, the printing ink, the plastic substrate and the front protective paint to be displayed.

8. A vacuum electroplating method for plastic bonding according to claim 7, characterized in that: Step 5: Laser engraving symbol specific steps: Step 51: Prepare the laser engraving equipment, and fix the workpiece that has been treated with translucent primer, vacuum plating and topcoat on the workbench of the laser engraving equipment; Step 52: Setting the parameters of laser engraving, including laser power set to 50W-60W, engraving speed 0-85mm / min, and repeatability accuracy: ±0.1mm; Step 53: Start the laser engraving device and start the engraving operation; the laser beam will engrave the translucent primer, vacuum plating layer and topcoat on the surface of the workpiece according to the preset graphic data to display the required symbols; Step 54: After engraving is completed, check the quality of the symbol. The color of the symbol is the transparent color of the plastic substrate. Step 55: Clean the engraved workpiece to remove the debris and debris generated during the engraving process.

9. A vacuum electroplating method for plastic bonding according to claim 7, characterized in that: Step 6: Printing ink Specific steps: Step 61: prepare ink that meets the requirements for symbol display, place the workpiece after laser engraving the symbol on a printing device, and use the printing device to print ink on the symbol; Step 62: Adjust the parameters of the printing equipment, including printing pressure and speed, to control the output of ink. Printing pressure: The printing pressure is set at 10N / cm 2 -30N / cm 2 The printing speed is set between 100mm / s-500mm / s; the ink output is 0.5g / m 2 -2g / m 2 between; Step 63: The thickness of the printed ink layer is between 1um and 20um, and the ink color is selected according to the symbol display.

10. A vacuum electroplating method for plastic bonding according to claim 7, characterized in that: Step 8: An LED light source with a diameter of 2mm-6mm and a power of 0.2W-1.6W is set on the back side of the back protective paint.

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