Novel integrated plastic coating manufacturing process

Abstract

The invention relates to the technical field of plastic coating manufacturing, in particular to a novel integrated plastic coating manufacturing process which comprises the following steps: S1, matrix pretreatment; s2, preparing a plastic coating material; s3, plastic coating molding; s4, preliminary quality detection; s5, product treatment; s6, final quality detection; and S7, packaging. According to the novel integrated plastic coating manufacturing process, through mechanical polishing, degreasing, surface activation, primer pre-coating and the like, the adhesive force of a plastic coating layer and a base body is greatly enhanced, the service life of a product is effectively prolonged, and in the plastic coating material preparation link, material selection is accurate, a formula is reasonably added, and pelleting and drying are strict, so that the production efficiency is greatly improved. The material is endowed with excellent properties such as weather resistance, oxidation resistance and flame retardance, the application range of the product is widened, two checks of initial detection and final detection are set in the aspect of quality detection, the problems of appearance, size and basic performance can be found in time through initial detection, the process is convenient to adjust, the final detection is comprehensive and strict, the quality of delivered products is reliable, the defective rate is reduced, and the overall quality is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of plastic-coated production, and particularly relates to a novel integrated plastic-coated production process. Background Art

[0002] In modern industry and daily life, plastic-coated products are widely used. From various pipes and profiles in the construction field to the protection of components in mechanical manufacturing, from the housing encapsulation of electronic devices to the surface treatment of household items, the plastic-coated technology plays a key role. The plastic-coated technology can not only provide additional protection for the base material and extend its service life, but also improve the appearance texture of the product and enhance the overall quality of the product.

[0003] However, the existing plastic-coated production processes are complex and have low production efficiency. The plastic-coated products prepared by traditional processes have poor performance in terms of chemical corrosion resistance, weather aging resistance, etc., and it is difficult to be stably used in harsh industrial environments or outdoor environments. The bonding strength between the plastic-coated layer and the base is not good, and the plastic-coated layer is prone to peeling off from the base during long-term use or under external force impact, which cannot well meet the market demand. Therefore, a novel integrated plastic-coated production process is needed. Summary of the Invention

[0004] The purpose of the present invention is to provide a novel integrated plastic-coated production process to solve the problems raised in the above background art.

[0005] To achieve the above purpose, the present invention provides the following technical solution: A novel integrated plastic-coated production process, comprising the following steps:

[0006] S1. Substrate pretreatment;

[0007] S2. Preparation of plastic-coated materials;

[0008] S3. Plastic-coated forming;

[0009] S4. Preliminary quality inspection;

[0010] S5. Product treatment;

[0011] S6. Final quality inspection;

[0012] S7. Packaging.

[0013] Preferably, the specific method in the step S1, raw material preparation is as follows:

[0014] S1-1. For metal substrates such as steel and aluminum alloy, select sandpaper or grinding wheels with appropriate grit according to the initial surface roughness. For a relatively rough steel substrate, first use coarse sandpaper with 80-120 mesh to remove impurities such as rust and scale on the surface, and then sequentially replace with 200-400 mesh sandpaper for fine grinding until the surface roughness reaches Ra3.2-Ra6.3μm. For a relatively smooth aluminum alloy substrate, directly use 200-300 mesh sandpaper for grinding to enhance the surface roughness;

[0015] S1-2. Immerse the ground substrate in a degreasing agent solution for degreasing treatment. The degreasing agent can be an alkaline degreasing agent, whose main components are sodium hydroxide, sodium carbonate and surfactant, and the concentration is controlled between 5% and 10%. During degreasing treatment, the solution temperature is maintained at 40-50°C, and the treatment time is 15-20 minutes. During the treatment process, ultrasonic assistance can be used for degreasing, and the ultrasonic frequency is set at 20-40kHz. After degreasing is completed, thoroughly rinse the surface of the substrate with flowing water to remove the residual degreasing agent;

[0016] S1-3. Use the chemical etching method to perform surface activation treatment on the degreased substrate. For the steel substrate, immerse it in a solution containing 5%-8% hydrochloric acid for 3-5 minutes to form a microscopic concave-convex structure on the substrate surface. For the aluminum alloy substrate, use a solution containing 2%-5% hydrofluoric acid for activation treatment, and the soaking time is controlled within 2-4 minutes. After the treatment is completed, quickly rinse the substrate with deionized water, and then dry the surface moisture with nitrogen;

[0017] S1-4. Uniformly spray a layer of primer on the activated substrate surface. The primer can be an epoxy resin-based primer. During spraying, control the pressure of the spray gun at 0.3-0.5MPa, and keep the distance between the spray gun and the substrate surface at 15-20cm to ensure uniform coverage of the primer. After spraying is completed, put the substrate into an oven and dry it at a temperature of 60-70°C for 10-15 minutes to cure the primer.

[0018] Preferably, the specific method in the step S2 of preparing the plastic coating material is as follows:

[0019] S2-1. Reasonably select the plastic coating material according to the usage environment and performance requirements of the product. In the field of chemical equipment that requires chemical corrosion resistance, give priority to using polytetrafluoroethylene or polyvinylidene fluoride. In the field of mechanical parts that require good flexibility and wear resistance, thermoplastic elastomers can be selected. In the general protective packaging field, polyethylene or polyvinyl chloride can be chosen;

[0020] S2-2. Add appropriate amount of functional additives to the selected plastic packaging material. For products that need to be used outdoors, add 0.3% to 0.6% of UV stabilizers, such as benzophenone or benzotriazole compounds, to improve the weather resistance of the product. Add 0.2% to 0.5% of antioxidants, such as hindered phenol antioxidants, to prevent oxidative degradation of the material during processing and use. If the product has flame retardant requirements, add 5% to 15% of flame retardants according to the flame retardant level, such as inorganic flame retardants such as aluminum hydroxide and magnesium hydroxide or phosphorus-based and halogen-based organic flame retardants. Fully mix the plastic packaging material and additives in a high-speed mixer. Set the stirring speed to 800-1000r / min and the stirring time to 10 to 15 minutes to ensure that the additives are evenly dispersed in the plastic packaging material.

[0021] S2-3, the mixed material is granulated through a twin-screw extruder, the temperature of the extruder barrel is set to 160-170°C, 170-180°C, 180-190°C, 190-200°C from the hopper to the die, and the screw speed is controlled at 150-200r / min. During the granulation process, the strips extruded through the die are water-cooled or air-cooled, and then cut into uniform particles by a pelletizer, and the particle size of the particles is controlled between 2-4mm;

[0022] S2-4. Put the plastic-coated particles after granulation into a drying oven for drying to remove the moisture adsorbed on the surface of the particles. The temperature of the drying oven is set to 50-60°C and the drying time is 2-3 hours. The particles after drying should be sealed and stored in time.

[0023] Preferably, the basic principle of the S3, overmolding step is as follows:

[0024] S3-1. Choose appropriate plastic overmolding equipment according to the shape and size of the product. For pipe products, such as wires and cables, water pipes, etc., use extruders for plastic overmolding. For parts with complex shapes, such as automotive interiors, electronic equipment housings, etc., use injection molding machines for molding. For large containers or hollow products, such as plastic barrels, toy balls, etc., use blow molding machines for processing.

[0025] S3-2. Add the dried plastic-coated particles into the hopper of the corresponding molding equipment. For the injection molding machine, the barrel temperature is set according to the characteristics of the selected plastic-coated material. For example, the barrel temperature of polyvinyl chloride is generally 180-220°C, and gradually increases from the hopper to the head. For the extruder, the barrel temperature is set between 170-210°C. The temperature of the blow molding machine is adjusted according to the specific process requirements, generally within the range of 160-200°C. The plastic-coated material is gradually melted through the heating system to achieve a good flow state;

[0026] S3-3. Add the dried plastic-coated particles into the hopper of the corresponding molding equipment. For an injection molding machine, the barrel temperature is set according to the characteristics of the selected plastic-coated material. For example, the barrel temperature of polyvinyl chloride is generally 180 - 220 °C, gradually increasing from the hopper to the nozzle. For an extruder, the barrel temperature is set between 170 - 210 °C. The temperature of the blow molding machine is adjusted according to specific process requirements, generally in the range of 160 - 200 °C. The plastic-coated material is gradually melted through the heating system to reach a good flow state;

[0027] S3-4. During the plastic coating molding process, use a cooling device to cool and shape the molded product. The cooling medium is usually circulating water, and the water temperature is controlled at 15 - 25 °C. For injection molded products, cooling channels are set in the mold, and the heat is carried away by circulating water. The cooling time is determined according to the thickness and material of the product, generally 10 - 60 seconds. For extruded molded products, a cooling water tank is set at the die to quickly cool the plastic-coated product after extrusion. For blow molded products, cooling air ducts are set on the mold surface for air cooling, and the cooling air speed is controlled at 3 - 5 m / s. During the cooling process, the flow rate and temperature distribution of the cooling medium can be reasonably adjusted according to the shape and size of the product to ensure uniform cooling and solidification of the plastic-coated layer and tight bonding with the substrate.

[0028] Preferably, the specific method in the step S4, preliminary quality inspection, is as follows:

[0029] S4-1. Conduct an appearance inspection on the product after plastic coating molding. Carefully check whether there are defects such as bubbles, cracks, impurities, flow marks, etc. on the surface of the plastic-coated layer. For the detected minor defects, mark and record them in a timely manner;

[0030] S4-2. Use measuring tools such as calipers, micrometers, projectors, etc. to measure the key dimensions of the product, including length, width, thickness, hole diameter, etc. Compare the measurement results with the design dimensions to ensure that the product size error is controlled within ±0.5 mm. For products with size deviations beyond the allowable range, analyze the reasons and make corresponding adjustments, such as checking whether the mold is worn and whether the molding process parameters are appropriate, etc.;

[0031] S4-3. Conduct a simple performance evaluation on the product. Feel the hardness and smoothness of the plastic-coated layer by hand to preliminarily judge whether its physical properties are normal. For products with special performance requirements, such as the insulation performance of wires and cables and the pressure resistance performance of pipes, conduct preliminary functional tests to timely detect potential quality problems.

[0032] Preferably, the specific method in the step S5, product treatment, is as follows:

[0033] S5-1. For injection-molded products, the product is ejected from the mold by the ejection device of the mold. During the ejection process, it is necessary to pay attention to controlling the ejection speed and ejection force to avoid damaging the product. For extrusion-molded and blow-molded products, carefully remove the product from the mold or equipment to ensure that the plastic-coated layer is not scratched or collided;

[0034] S5-2. Place the demolded product in an oven for annealing treatment. The oven temperature is set at 80-90°C, and the annealing time is 30-60 minutes. During the annealing process, the products should be evenly placed in the oven to avoid mutual extrusion and ensure uniform annealing effect;

[0035] S5-3. Perform surface treatment on the annealed product. First, use sandpaper for grinding. According to the roughness and requirements of the product surface, select sandpaper with appropriate grit. Start with coarse sandpaper of 120-200 mesh, and gradually replace it with fine sandpaper of 400-800 mesh for fine grinding to remove surface defects and unevenness. Then, use a polishing wheel for polishing. The polishing wheel can be a wool wheel or a sponge wheel, and operate with polishing wax to make the surface roughness of the product reach Ra0.8-Ra1.6μm, presenting a smooth and bright appearance;

[0036] S5-4. Clean the product after surface treatment. The cleaning method can be a combination of ultrasonic cleaning and rinsing with clean water. First, place the product in an ultrasonic cleaning tank containing an appropriate amount of cleaning agent. The ultrasonic frequency is set at 30-50kHz, and the cleaning time is 10-15 minutes to make the impurities fully detach from the product surface. Then, rinse the product with flowing clean water to ensure that there is no residue of the cleaning agent on the surface. Finally, dry the surface moisture of the product with compressed air

[0037] Preferably, the specific method in the S6. Final quality inspection step is as follows:

[0038] S6-1. Conduct a detailed inspection of the product appearance again to ensure that the surface has no defects, the color is uniform, and the glossiness meets the requirements. Use professional appearance inspection equipment, such as a color difference meter, a glossiness meter, etc., to quantitatively detect the color and glossiness of the product and compare it with the standard sample to ensure that the appearance quality of the product reaches a high standard;

[0039] S6-2. Use high-precision measuring instruments to measure the key dimensions of the product again. For products with high dimensional accuracy requirements, a coordinate measuring machine can be used for measurement, and the measurement error is controlled within ±0.05mm. If it is found that the dimensions are still deviated, analyze the reasons and adjust or scrap the product;

[0040] S6-3. Use the cross-cut method or peel test to test the bonding strength between the plastic coating and the substrate. Use a tool to draw grids of a certain specification, then paste and quickly tear off the tape, and observe the peeling situation of the plastic coating in the grid area. According to the standard rating, the bonding strength is required to reach level 1-2. For the peel test, a special tensile testing machine is used to peel the plastic coating from the substrate and measure the tensile force during the peeling process. The peel strength is required to be greater than 10 N / cm to ensure that the plastic coating is firmly bonded to the substrate;

[0041] S6-4. According to the usage requirements of the product, comprehensively test the various performances of the product. For corrosion-resistant products, conduct chemical corrosion tests by immersing the products in specific chemical media and observing the corrosion situation of the plastic coating after a certain period. For weather-resistant products, conduct artificial accelerated aging tests to simulate environmental conditions such as sunlight, temperature, and humidity outdoors and test the performance changes of the products after a certain period. Test the mechanical properties such as tensile strength, impact strength, and bending strength of the products to ensure that the product performance meets the actual usage requirements.

[0042] Preferably, the specific method in the S7 packaging step is as follows:

[0043] S7-1. Select moisture-proof and anti-static packaging materials to package the products, such as moisture-proof plastic bags, anti-static bubble bags, cardboard boxes, etc. For some precision products or products sensitive to static electricity, anti-static packaging materials are preferably used;

[0044] S7-2. Design a suitable packaging method according to the shape and size of the product. For small products, single packaging or combined packaging of multiple products can be adopted. Put the products into plastic bags or cardboard boxes and add appropriate cushioning materials, such as foam plastics and sponges. For large products, winding packaging or wooden box packaging can be used;

[0045] S7-3. Clearly mark information such as the name, specification, model, production date, batch number, shelf life, and usage precautions of the product on the outer packaging of the product. The marked content should be printed in a clear and non-fading manner to ensure that the information is accurate and easy to identify.

[0046] Preferably, in the S2-4 step, during the drying process, a circulating air system can be adopted.

[0047] Compared with the prior art, the beneficial effects of the present invention are:

[0048] 1. Through multi-step and refined substrate pretreatment, including mechanical grinding, degreasing, surface activation, and pre-coating of primer, etc., the present invention significantly improves the adhesion between the plastic coating and the substrate, and greatly extends the service life of the product;

[0049] 2. In the preparation process of the plastic-coated material, precise material selection, reasonable additive formula, and strict granulation and drying processes endow the plastic-coated material with more excellent comprehensive properties, such as weather resistance, oxidation resistance, flame retardancy, etc., expanding the application fields of the product;

[0050] 3. Two quality inspection links are set up, namely the preliminary quality inspection and the final quality inspection. The preliminary inspection can promptly detect problems with appearance, dimensions, and basic properties, facilitating timely adjustment of process parameters. The final inspection is comprehensive and strict, from the quantitative inspection of appearance to the high-precision measurement of dimensions, and then to the adhesion and various performance tests, ensuring the reliable quality of the delivered products, reducing the defective rate, and improving the overall quality level of the products. Detailed implementation manners

[0051] Unless otherwise clearly specified in the context, nouns without a quantifier and nouns modified by "the" include singular and plural referents.

[0052] As used in the specification and claims, the terms "comprising", "including", "having", "may", "containing", and their variants are open transitional phrases, terms, or words that mean the presence of the specified component / step is required and the presence of other components / steps is permitted. However, such a description should also be interpreted as describing the composition or method as "consisting of" and "consisting essentially of" the listed components / steps, which allows only the specified components / steps and any inevitable impurities that may result therefrom, and excludes other components / steps.

[0053] The numerical values in the specification and claims of the present application should be understood to include the same numerical values when reduced to the same number of significant figures and numerical values that differ from the said values by less than the experimental error of the conventional measurement techniques used to determine the said values of the type described in the present application.

[0054] All ranges disclosed herein include the indicated endpoints and can be combined independently (e.g., the range of "2 grams to 10 grams" includes the endpoints 2 grams and 10 grams, as well as all intermediate values).

[0055] The terms "about" and "approximate" can be used to include any numerical value that can vary without changing the basic function of the value. When used with a range, "about" and "approximate" also disclose the range defined by the absolute values of the two endpoints. For example, "about 2 to about 4" also discloses the range of "2 to 4". Generally, the terms "about" and "approximate" can refer to ±10% of the indicated number. However, for temperature, the term "about" means ±1°C.

[0056] Unless otherwise clearly specified, the percentage of an element should be considered as the weight percentage of the said alloy.

[0057] This disclosure may relate to the temperature of certain method steps. It should be noted that these indicators generally refer to the temperature set by a heat source (such as a furnace), rather than necessarily the temperature that the heated material must reach.

[0058] The present invention provides a novel one-piece plastic coating manufacturing process, including the following steps:

[0059] S1. Substrate pretreatment;

[0060] S1-1. For metal substrates such as steel and aluminum alloy, according to the initial surface roughness situation, select sandpaper or grinding wheels with appropriate grit sizes for mechanical grinding. For relatively rough steel substrates, first use 80-120 mesh coarse sandpaper to remove impurities such as rust and scale on the surface, and then sequentially replace with 200-400 mesh sandpaper for fine grinding until the surface roughness reaches Ra3.2-Ra6.3μm. For relatively smooth aluminum alloy substrates, directly use 200-300 mesh sandpaper for grinding to enhance the surface roughness and improve the adhesion of the plastic coating layer;

[0061] S1-2. Put the ground substrate into a degreasing agent solution for degreasing treatment. The degreasing agent can be an alkaline degreasing agent, whose main components are sodium hydroxide, sodium carbonate and surfactant, and the concentration is controlled between 5% and 10%. During the degreasing treatment, the solution temperature is maintained at 40-50°C, and the treatment time is 15-20 minutes. During the treatment process, ultrasonic assistance can be used for degreasing, and the ultrasonic frequency is set at 20-40kHz. After degreasing is completed, thoroughly rinse the surface of the substrate with flowing clean water to remove the remaining degreasing agent;

[0062] S1-3. Use the chemical corrosion method to conduct surface activation treatment on the degreased substrate. For steel substrates, immerse them in a solution containing 5%-8% hydrochloric acid for 3-5 minutes to form a microscopic concave-convex structure on the substrate surface and increase the surface area. For aluminum alloy substrates, use a solution containing 2%-5% hydrofluoric acid for activation treatment, and the soaking time is controlled within 2-4 minutes. After the treatment is completed, quickly rinse the substrate with deionized water, and then dry the surface moisture with nitrogen;

[0063] S1-4. Uniformly spray a layer of primer on the surface of the activated substrate. The primer can be an epoxy resin-based primer. During spraying, control the pressure of the spray gun at 0.3-0.5MPa, and keep the distance between the spray gun and the substrate surface at 15-20cm to ensure uniform coverage of the primer. After spraying is completed, put the substrate into an oven and dry it at a temperature of 60-70°C for 10-15 minutes to cure the primer and enhance the bonding force between the substrate and the plastic coating layer.

[0064] S2. Plastic coating materials;

[0065] S2-1. Reasonably select the plastic-coated material according to the usage environment and performance requirements of the product. In the field of chemical equipment that requires chemical corrosion resistance, give priority to using polytetrafluoroethylene or polyvinylidene fluoride. In the field of mechanical parts that require good flexibility and wear resistance, thermoplastic elastomers can be selected. In general protective packaging fields, polyethylene or polyvinyl chloride can be chosen.

[0066] S2-2. Add appropriate functional additives to the selected plastic-coated material. For products that need to be used outdoors, add 0.3% - 0.6% of ultraviolet stabilizers, such as benzophenone compounds or benzotriazole compounds, to improve the weather resistance of the product. Add 0.2% - 0.5% of antioxidants, such as hindered phenol antioxidants, to prevent the material from oxidative degradation during processing and use. If the product has flame retardant requirements, add 5% - 15% of flame retardants according to the flame retardant grade, such as inorganic flame retardants like aluminum hydroxide and magnesium hydroxide, or phosphorus-based and halogen-based organic flame retardants. Thoroughly mix the plastic-coated material and the additives in a high-speed mixer. Set the stirring speed to 800 - 1000 r / min and the stirring time to 10 - 15 minutes to ensure that the additives are evenly dispersed in the plastic-coated material.

[0067] S2-3. Granulate the mixed material through a twin-screw extruder. The temperature of the extruder barrel is set from the hopper to the head as 160 - 170 °C, 170 - 180 °C, 180 - 190 °C, 190 - 200 °C in sequence. Control the screw speed at 150 - 200 r / min. During the granulation process, the strip-shaped material extruded through the die head is cooled by water or air and then cut into uniform particles by a pelletizer. Control the particle size between 2 - 4 mm.

[0068] S2-4. Put the granulated plastic-coated particles into a drying oven for drying treatment to remove the moisture adsorbed on the particle surface. Set the temperature of the drying oven to 50 - 60 °C and the drying time to 2 - 3 hours. The dried particles should be sealed and stored in time. During the drying process, a circulating air system can be adopted to make the temperature in the oven uniform and ensure that the particles are dried sufficiently.

[0069] S3. Plastic coating forming;

[0070] S3-1. Select appropriate plastic coating forming equipment according to the shape and size of the product. For pipe products, such as wires and cables, water pipes, etc., use an extruder for plastic coating forming. For parts with complex shapes, such as automotive interior parts, electronic device casings, etc., use an injection molding machine for forming. For large containers or hollow products, such as plastic buckets, toy balls, etc., select a blow molding machine for processing.

[0071] S3-2. Add the dried plastic-coated particles into the hopper of the corresponding molding equipment. For an injection molding machine, the barrel temperature is set according to the characteristics of the selected plastic-coated material. For example, the barrel temperature of polyvinyl chloride is generally 180 - 220°C, gradually increasing from the hopper to the nozzle. For an extruder, the barrel temperature is set between 170 - 210°C. The temperature of the blow molding machine is adjusted according to specific process requirements, generally in the range of 160 - 200°C. The plastic-coated material is gradually melted through the heating system to reach a good flow state;

[0072] S3-3. Add the dried plastic-coated particles into the hopper of the corresponding molding equipment. For an injection molding machine, the barrel temperature is set according to the characteristics of the selected plastic-coated material. For example, the barrel temperature of polyvinyl chloride is generally 180 - 220°C, gradually increasing from the hopper to the nozzle. For an extruder, the barrel temperature is set between 170 - 210°C. The temperature of the blow molding machine is adjusted according to specific process requirements, generally in the range of 160 - 200°C. The plastic-coated material is gradually melted through the heating system to reach a good flow state;

[0073] S3-4. During the plastic coating molding process, use a cooling device to cool and shape the molded product. The cooling medium is usually circulating water, and the water temperature is controlled at 15 - 25°C. For injection molded products, cooling channels are set in the mold, and heat is removed by circulating water. The cooling time is determined according to the thickness and material of the product, generally 10 - 60 seconds. For extruded molded products, a cooling water tank is set at the die opening to quickly cool the plastic-coated product after extrusion. For blow molded products, cooling air ducts are set on the mold surface for air cooling, and the cooling air speed is controlled at 3 - 5 m / s. During the cooling process, the flow rate and temperature distribution of the cooling medium can be reasonably adjusted according to the shape and size of the product to ensure uniform cooling and solidification of the plastic-coated layer and tight bonding with the substrate.

[0074] S4. Preliminary quality inspection;

[0075] S4-1. Conduct an appearance inspection on the plastic-coated molded product, carefully check whether there are defects such as bubbles, cracks, impurities, flow marks, etc. on the surface of the plastic-coated layer. For the discovered minor defects, mark and record them in a timely manner;

[0076] S4-2. Use measuring tools such as calipers, micrometers, projectors, etc. to measure the key dimensions of the product, including length, width, thickness, hole diameter, etc. Compare the measurement results with the design dimensions to ensure that the product size error is controlled within ±0.5 mm. For products with size deviations beyond the allowable range, analyze the reasons and make corresponding adjustments, such as checking whether the mold is worn and whether the molding process parameters are appropriate, etc.;

[0077] S4-3. Conduct a simple performance evaluation of the product. Touch it by hand to feel the hardness and smoothness of the plastic-coated layer, and preliminarily judge whether its physical properties are normal. For products with special performance requirements, such as the insulation performance of wires and cables and the pressure resistance performance of pipes, conduct preliminary functional tests to timely discover potential quality problems.

[0078] S5. Product processing.

[0079] S5-1. For injection-molded products, eject the product from the mold through the ejection device of the mold. During the ejection process, pay attention to controlling the ejection speed and ejection force to avoid damaging the product. For extrusion-molded and blow-molded products, carefully remove the product from the mold or equipment to ensure that the plastic-coated layer is not scratched or collided.

[0080] S5-2. Put the demolded product into the oven for annealing treatment. The oven temperature is set at 80-90°C, and the annealing time is 30-60 minutes. During the annealing process, the products should be evenly placed in the oven to avoid mutual extrusion and ensure uniform annealing effect.

[0081] S5-3. Conduct surface treatment on the annealed product. First, use sandpaper for grinding. According to the roughness and requirements of the product surface, select sandpaper with appropriate grit. Start with coarse sandpaper of 120-200 mesh, and gradually replace it with fine sandpaper of 400-800 mesh for fine grinding to remove surface defects and unevenness. Then use a polishing wheel for polishing. The polishing wheel can be a wool wheel or a sponge wheel, and operate with polishing wax to make the surface roughness of the product reach Ra0.8-Ra1.6μm, presenting a smooth and bright appearance.

[0082] S5-4. Clean the surface-treated product. The cleaning method can be a combination of ultrasonic cleaning and rinsing with clean water. First, put the product into an ultrasonic cleaning tank containing an appropriate amount of cleaning agent. The ultrasonic frequency is set at 30-50kHz, and the cleaning time is 10-15 minutes to make the impurities fully detach from the product surface. Then rinse the product with flowing clean water to ensure that there is no cleaning agent residue on the surface. Finally, blow dry the surface moisture of the product with compressed air.

[0083] S6. Final quality inspection;

[0084] S6-1. Conduct a detailed inspection of the product appearance again to ensure that there are no defects on the surface, the color is uniform, and the glossiness meets the requirements. Use professional appearance inspection equipment, such as a color difference meter and a glossiness meter, to quantitatively detect the color and glossiness of the product and compare it with the standard sample to ensure that the product appearance quality reaches a high standard.

[0085] S6-2. Use high-precision measuring instruments to measure the key dimensions of the product again. For products with high dimensional accuracy requirements, a coordinate measuring machine can be used for measurement, and the measurement error is controlled within ±0.05 mm. If any dimensional deviation is found, analyze the reasons and adjust or scrap the product;

[0086] S6-3. Use the cross-cut method or peel test to test the adhesion between the plastic coating and the substrate. Use a tool to cut a grid of a certain specification, then stick and quickly tear off the tape, and observe the peeling situation of the plastic coating in the grid area. According to the standard rating, the adhesion is required to reach level 1-2. The peel test is to use a special tensile testing machine to peel the plastic coating from the substrate and measure the tensile force during the peeling process. The peel strength is required to be greater than 10 N / cm to ensure a firm bond between the plastic coating and the substrate;

[0087] S6-4. According to the usage requirements of the product, comprehensively test the various performances of the product. For corrosion-resistant products, conduct a chemical corrosion test by immersing the product in a specific chemical medium and observing the corrosion situation of the plastic coating after a certain period of time. For weather-resistant products, conduct an artificial accelerated aging test to simulate outdoor environmental conditions such as light, temperature, and humidity, and test the performance changes of the product after a certain period of time. Test the mechanical properties of the product such as tensile strength, impact strength, and bending strength to ensure that the product performance meets the actual usage requirements.

[0088] S7. Packaging;

[0089] S7-1. Select moisture-proof and anti-static packaging materials to package the product, such as moisture-proof plastic bags, anti-static bubble bags, paper boxes, etc. For some precision products or products sensitive to static electricity, give priority to using anti-static packaging materials;

[0090] S7-2. Design a suitable packaging method according to the shape and size of the product. For small products, single packaging or combined packaging of multiple products can be used. Put the product into a plastic bag or paper box and add appropriate cushioning materials such as foam plastics and sponges. For large products, winding packaging or wooden box packaging can be used;

[0091] S7-3. Clearly mark the product name, specification, model, production date, batch number, shelf life, usage precautions and other information on the outer packaging of the product. The marking content should be printed in a clear and non-fading manner to ensure that the information is accurate and easy to identify.

[0092] Specific steps: For metal substrates such as steel and aluminum alloy, select sandpaper or grinding wheels with appropriate grit according to the initial surface roughness. For the relatively rough steel substrate, first use coarse sandpaper with 80-120 mesh to remove impurities such as rust and scale on the surface, and then sequentially replace with 200-400 mesh sandpaper for fine grinding until the surface roughness reaches Ra3.2-Ra6.3μm. For the relatively smooth aluminum alloy substrate, directly use sandpaper with 200-300 mesh to polish to enhance the surface roughness and improve the adhesion of the plastic coating layer. Immerse the polished substrate in a degreasing agent solution for degreasing treatment. The degreasing agent can be an alkaline degreasing agent, whose main components are sodium hydroxide, sodium carbonate and surfactants, and the concentration is controlled between 5% and 10%. During degreasing treatment, the solution temperature is maintained at 40-50°C, and the treatment time is 15-20 minutes. During the treatment process, ultrasonic assistance can be used for degreasing, and the ultrasonic frequency is set at 20-40kHz. After degreasing, thoroughly rinse the surface of the substrate with flowing water to remove the remaining degreasing agent. Use the chemical corrosion method to perform surface activation treatment on the degreased substrate. For the steel substrate, immerse it in a solution containing 5%-8% hydrochloric acid for 3-5 minutes to form a microscopic concave-convex structure on the substrate surface and increase the surface area. For the aluminum alloy substrate, use a solution containing 2%-5% hydrofluoric acid for activation treatment, and the soaking time is controlled within 2-4 minutes. After the treatment, quickly rinse the substrate with deionized water and then blow dry the surface moisture with nitrogen. Uniformly spray a layer of primer on the activated substrate surface. The primer can be an epoxy resin-based primer. When spraying, control the pressure of the spray gun at 0.3-0.5MPa, and keep the distance between the spray gun and the substrate surface at 15-20cm to ensure uniform coverage of the primer. After spraying, put the substrate into an oven and dry it at a temperature of 60-70°C for 10-15 minutes to cure the primer and enhance the bonding force between the substrate and the plastic coating layer. According to the use environment and performance requirements of the product, reasonably select the plastic coating material. In the field of chemical equipment that requires chemical corrosion resistance, give priority to using polytetrafluoroethylene or polyvinylidene fluoride. In the field of mechanical parts that require good flexibility and wear resistance, thermoplastic elastomers can be selected. In the general protective packaging field, polyethylene or polyvinyl chloride can be chosen. Add appropriate functional additives to the selected plastic coating material. For products that need to be used outdoors, add 0.3%-0.6% of ultraviolet stabilizers such as benzophenone compounds or benzotriazole compounds to improve the weather resistance of the product, and add 0.2%-0.5% of antioxidants such as hindered phenol antioxidants to prevent the material from oxidative degradation during processing and use. If the product has flame retardant requirements, add 5%-15% of flame retardants such as aluminum hydroxide, magnesium hydroxide and other inorganic flame retardants or phosphorus-based and halogen-based organic flame retardants according to the flame retardant grade. Thoroughly mix the plastic coating material and the additives in a high-speed mixer, set the stirring speed at 800-1000r / min, and the stirring time is 10-15 minutes.Ensure that the additive is evenly dispersed in the plastic-coated material. Granulate the mixed material through a twin-screw extruder. The temperatures of the extruder barrel are set sequentially from the hopper to the head as 160 - 170 °C, 170 - 180 °C, 180 - 190 °C, and 190 - 200 °C. The screw speed is controlled at 150 - 200 r / min. During granulation, the strip extruded through the die head is cooled by water or air and then cut into uniform particles by a pelletizer. The particle size is controlled between 2 - 4 mm. Put the plastic-coated particles after granulation into a drying oven for drying treatment to remove the moisture adsorbed on the particle surface. The temperature of the drying oven is set at 50 - 60 °C, and the drying time is 2 - 3 hours. The dried particles should be sealed and stored in time. During the drying process, a circulating air system can be adopted to make the temperature in the oven uniform and ensure that the particles are dried sufficiently. According to the shape and size of the product, select the appropriate plastic-coated forming equipment. For pipe products such as wires and cables, water pipes, etc., use an extruder for plastic coating. For complex-shaped parts such as automotive interior parts, electronic device casings, etc., use an injection molding machine for forming. For large containers or hollow products such as plastic buckets, toy balls, etc., select a blow molding machine for processing. Put the dried plastic-coated particles into the hopper of the corresponding forming equipment. For an injection molding machine, the barrel temperature is set according to the characteristics of the selected plastic-coated material. For example, the barrel temperature of polyvinyl chloride is generally 180 - 220 °C and gradually increases from the hopper to the head. For an extruder, the barrel temperature is set between 170 - 210 °C. The temperature of the blow molding machine is adjusted according to specific process requirements, generally in the range of 160 - 200 °C. Gradually melt the plastic-coated material through the heating system to reach a good flow state. Put the dried plastic-coated particles into the hopper of the corresponding forming equipment. For an injection molding machine, the barrel temperature is set according to the characteristics of the selected plastic-coated material. For example, the barrel temperature of polyvinyl chloride is generally 180 - 220 °C and gradually increases from the hopper to the head. For an extruder, the barrel temperature is set between 170 - 210 °C. The temperature of the blow molding machine is adjusted according to specific process requirements, generally in the range of 160 - 200 °C. Gradually melt the plastic-coated material through the heating system to reach a good flow state. During the plastic-coated forming process, use a cooling device to cool and shape the formed product. The cooling medium is usually circulating water, and the water temperature is controlled at 15 - 25 °C. For injection-molded products, cooling channels are set in the mold to take away heat through circulating water. The cooling time is determined according to the thickness and material of the product, generally 10 - 60 seconds. For extrusion-molded products, a cooling water tank is set at the die head to quickly cool the plastic-coated product after extrusion. For blow-molded products, cooling air ducts are set on the mold surface for cooling by air, and the cooling air speed is controlled at 3 - 5 m / s. During the cooling process, the flow rate and temperature distribution of the cooling medium can be reasonably adjusted according to the shape and size of the product to ensure that the plastic-coated layer is evenly cooled and solidified and tightly bonded to the substrate. Conduct an appearance inspection on the plastic-coated formed product and carefully check whether there are defects such as bubbles, cracks, impurities, flow marks, etc. on the surface of the plastic-coated layer.For the detected minor defects, mark and record them in a timely manner. Use measuring tools such as calipers, micrometers, and projectors to measure the key dimensions of the product, including length, width, thickness, hole diameter, etc. Compare the measurement results with the design dimensions to ensure that the product size error is controlled within ±0.5 mm. For products with size deviations exceeding the allowable range, analyze the reasons and make corresponding adjustments, such as checking whether the mold is worn and whether the molding process parameters are appropriate. Conduct a simple performance evaluation of the product. Feel the hardness and smoothness of the plastic coating by hand to preliminarily judge whether its physical properties are normal. For products with special performance requirements, such as the insulation performance of wires and cables and the pressure resistance performance of pipes, conduct preliminary functional tests to timely discover potential quality problems. For injection-molded products, eject the product from the mold through the ejection device of the mold. During the ejection process, pay attention to controlling the ejection speed and ejection force to avoid damaging the product. For extrusion-molded and blow-molded products, carefully remove the product from the mold or equipment to ensure that the plastic coating is not scratched or collided. Place the demolded product in an oven for annealing treatment. The oven temperature is set at 80 - 90 °C, and the annealing time is 30 - 60 minutes. During the annealing process, the products should be evenly placed in the oven to avoid mutual extrusion and ensure uniform annealing effect. Conduct surface treatment on the annealed product. First, use sandpaper for grinding. According to the roughness and requirements of the product surface, select sandpaper with appropriate grit. Start with coarse sandpaper of 120 - 200 mesh and gradually replace it with fine sandpaper of 400 - 800 mesh for fine grinding to remove surface defects and unevenness. Then use a polishing wheel for polishing treatment. The polishing wheel can be a wool wheel or a sponge wheel, and operate with polishing wax to make the surface roughness of the product reach Ra0.8 - Ra1.6 μm, presenting a smooth and bright appearance. Clean the surface-treated product. The cleaning method can be a combination of ultrasonic cleaning and rinsing with clean water. First, place the product in an ultrasonic cleaning tank containing an appropriate amount of cleaning agent. The ultrasonic frequency is set at 30 - 50 kHz, and the cleaning time is 10 - 15 minutes to make the impurities fully detach from the product surface. Then rinse the product with flowing clean water to ensure that there is no cleaning agent residue on the surface. Finally, blow dry the surface moisture of the product with compressed air. Check the appearance of the product in detail again to ensure that there are no defects on the surface, the color is uniform, and the glossiness meets the requirements. Use professional appearance detection equipment, such as a color difference meter and a glossiness meter, to quantitatively detect the color and glossiness of the product and compare it with the standard sample to ensure that the appearance quality of the product reaches a high standard. Use high-precision measuring instruments to measure the key dimensions of the product again. For products with high dimensional accuracy requirements, a coordinate measuring machine can be used for measurement, and the measurement error is controlled within ±0.05 mm. If it is found that there are still deviations in the dimensions, analyze the reasons and adjust or scrap the product. Use the cross-cut method or peel test to test the bonding strength between the plastic coating and the substrate. Use a tool to draw a grid of a certain specification,Then, paste it with tape and quickly tear it off. Observe the peeling situation of the plastic coating layer in the grid area. According to the standard rating, the adhesion is required to reach level 1-2. The peel test is carried out by a special tensile testing machine to peel the plastic coating layer from the substrate and measure the tensile force during the peeling process. The peel strength is required to be greater than 10 N / cm to ensure that the plastic coating layer is firmly bonded to the substrate. According to the usage requirements of the product, comprehensively test the various performances of the product. For corrosion-resistant products, conduct a chemical corrosion test by immersing the product in a specific chemical medium and observing the corrosion situation of the plastic coating layer after a certain period of time. For weather-resistant products, conduct an artificial accelerated aging test to simulate outdoor environmental conditions such as light, temperature, and humidity and test the performance changes of the product after a certain period of time. Test the mechanical properties of the product such as tensile strength, impact strength, and bending strength to ensure that the product performance meets the actual usage requirements. Select moisture-proof and anti-static packaging materials to package the product, such as moisture-proof plastic bags, anti-static bubble bags, cardboard boxes, etc. For some precision products or products sensitive to static electricity, give priority to using anti-static packaging materials. Design a suitable packaging method according to the shape and size of the product. For small products, they can be packaged individually or in combination. Put the product into a plastic bag or cardboard box and add an appropriate amount of cushioning materials such as foam plastics and sponges. For large products, they can be packaged by winding or in wooden boxes. Clearly mark the product name, specification, model, production date, batch number, shelf life, usage precautions, etc. on the outer packaging of the product. The marking content should be printed in a clear and non-fading manner to ensure that the information is accurate and easy to identify.,

[0093] Example 1:

[0094] S1. Raw material preparation;

[0095] S1-1. The heat sink substrate is made of aluminum alloy and its surface is relatively smooth. Select 200-mesh sandpaper for grinding to make the surface have fine concave and convex structures, enhance the roughness, and provide better conditions for the subsequent adhesion of the plastic coating layer;

[0096] S1-2. Put the ground heat sink into a 5% alkaline degreasing agent solution, keep the solution temperature at 40°C, and use 20 kHz ultrasonic wave to assist degreasing for 15 minutes. After degreasing, rinse it with a large amount of flowing clean water to ensure that the degreasing agent is completely removed;

[0097] S1-3. Immerse the degreased heat sink in a solution containing 2% hydrofluoric acid for 2 minutes to form microscopic concave and convex structures on its surface, increase the surface area, quickly rinse it with deionized water after treatment, and then dry it with nitrogen;

[0098] S1-4. Uniformly spray epoxy resin-based primer on the surface of the activated heat sink. Control the spray gun pressure at 0.3 MPa and keep the distance between the spray gun and the heat sink surface at 15 cm. After spraying, put the heat sink into an oven at 60 °C and dry it for 10 minutes to cure the primer.

[0099] S2. Prepare the plastic coating material;

[0100] S2-1. Considering the requirements of the electronic device for insulation and heat dissipation, select modified polyvinyl chloride with good insulation performance and certain heat dissipation ability as the plastic coating material;

[0101] S2-2. Add 0.3% ultraviolet stabilizer, 0.2% hindered phenol antioxidant and 8% aluminum hydroxide flame retardant. Mix the plastic coating material and the additives in a high-speed mixer at a speed of 800 r / min for 10 minutes to ensure uniform dispersion of the additives;

[0102] S2-3. Granulate the mixed material through a twin-screw extruder. Set the barrel temperature of the extruder from the hopper to the die head at 160 °C, 170 °C, 180 °C, 190 °C in sequence. Control the screw speed at 150 r / min. After the strip extruded from the die head is air-cooled, cut it into particles with a particle size of 2 mm by a pelletizer;

[0103] S2-4. Put the granulated plastic coating particles into a drying oven. Set the drying oven temperature at 50 °C and the drying time at 2 hours. Adopt a circulating air system during the drying process to make the temperature in the oven uniform. Seal and store the dried particles in time.

[0104] S3. Plastic coating molding;

[0105] S3-1. Due to the complex shape of the heat sink, select an injection molding machine for plastic coating molding;

[0106] S3-2. Add the dried plastic coating particles into the hopper of the injection molding machine. Set the barrel temperature at 180 - 210 °C according to the characteristics of the modified polyvinyl chloride, which gradually increases from the hopper to the die head. Make the plastic coating material melt into a good flowing state through the heating system;

[0107] S3-3. Accurately place the pre-treated heat sink in the injection mold. Control the injection pressure at 50 MPa and the injection time at 12 seconds to ensure that the plastic coating material uniformly wraps the heat sink;

[0108] S3-4. Set cooling water channels in the mold. The cooling medium is circulating water. Control the water temperature at 15 °C. Determine the cooling time at 20 seconds according to the thickness and material of the heat sink to make the plastic coating layer quickly cool and cure and tightly combine with the heat sink.

[0109] S4. Preliminary quality inspection;

[0110] S4-1. Conduct an appearance inspection on the heat sink after plastic coating. Carefully check whether there are defects such as air bubbles, cracks, impurities, and flow marks on the surface of the plastic coating. One tiny air bubble is found and marked.

[0111] S4-2. Use measuring tools such as calipers and projectors to measure the key dimensions of the heat sink, including thickness, hole diameter, etc., and ensure that the dimensional error is controlled within ±0.5 mm. After measurement, all dimensions meet the design requirements.

[0112] S4-3. Touch the plastic coating by hand to feel its hardness and smoothness, and preliminarily judge that the physical properties are normal. Conduct a simple insulation performance test on the heat sink, and no leakage phenomenon is found.

[0113] S5. Product processing;

[0114] S5-1. Eject the heat sink from the mold through the ejection device of the injection mold. Strictly control the ejection speed and ejection force during the ejection process to avoid damaging the product.

[0115] S5-2. Put the demolded heat sink into the oven. The oven temperature is set at 80 °C, and the annealing time is 30 minutes. When annealing, the heat sinks are evenly placed to avoid mutual extrusion to ensure uniform annealing effect.

[0116] S5-3. First, use a 120-mesh coarse sandpaper to polish the heat sink to remove some tiny surface defects, then use a 400-mesh fine sandpaper for fine polishing, and then use a wool wheel with polishing wax for polishing treatment to make the surface roughness of the product reach Ra0.8 μm and improve the appearance quality.

[0117] S5-4. Clean the heat sink by combining ultrasonic cleaning and rinsing with clean water. First, put it into an ultrasonic cleaning tank containing an appropriate amount of cleaning agent. The ultrasonic frequency is set at 30 kHz, and clean for 10 minutes to make the impurities fully detach from the product surface, then rinse with flowing clean water to ensure that there is no cleaning agent residue on the surface, and finally dry the surface moisture with compressed air.

[0118] S6. Final quality inspection;

[0119] S6-1. Conduct a detailed inspection on the appearance of the heat sink again to ensure that the surface has no defects, the color is uniform, and the glossiness meets the requirements. Use a color difference meter and a glossiness meter for quantitative detection. Compared with the standard sample, all indicators meet the standards.

[0120] S6-2. Use high-precision measuring instruments such as a coordinate measuring machine to measure the key dimensions of the heat sink again, and control the measurement error within ±0.05 mm. After measurement, all dimensions are within the allowable error range.

[0121] S6-3. The cross-cut method was used to test the bonding strength between the plastic coating layer and the substrate. A grid of a certain specification was scratched with a tool, and then tape was pasted and quickly peeled off. The peeling situation of the plastic coating layer in the grid area was observed. The result showed that the bonding strength reached Grade 1.

[0122] S6-4. Comprehensive performance tests were carried out on the heat sink, including insulation performance test, corrosion resistance test, and heat dissipation performance test under the working environment simulating electronic equipment. The test results showed that all performances met the usage requirements of the heat sink for electronic equipment.

[0123] S7. Packaging.

[0124] S7-1. An anti-static plastic film was selected to package the heat sink to prevent damage caused by static electricity during subsequent transportation and storage.

[0125] S7-2. Since the heat sink is small in size, it was packaged individually. The heat sink was neatly placed into a plastic film bag to ensure a tight package.

[0126] S7-3. Information such as product name, specification, model, production date, batch number, shelf life, and usage precautions was clearly marked on the plastic film bag. The marked content was printed in a clear and non-fading manner.

[0127] Specific steps: The heat sink base is made of aluminum alloy with a relatively smooth surface. Select 200-mesh sandpaper for grinding to create fine concave and convex structures on the surface, enhance the roughness, and provide better conditions for the subsequent attachment of the plastic coating layer. Place the ground heat sink in a 5% alkaline degreasing agent solution with the solution temperature maintained at 40°C, and use ultrasonic waves at 20 kHz to assist in degreasing for 15 minutes. After degreasing, rinse with a large amount of flowing clean water to ensure complete removal of the degreasing agent. Immerse the degreased heat sink in a solution containing 2% hydrofluoric acid for 2 minutes to form microscopic concave and convex structures on its surface and increase the surface area. After treatment, quickly rinse with deionized water and then dry with nitrogen. Uniformly spray an epoxy resin-based primer on the surface of the activated heat sink. Control the spray gun pressure at 0.3 MPa and keep the distance between the spray gun and the heat sink surface at 15 cm. After spraying, place the heat sink in an oven at 60°C and dry for 10 minutes to cure the primer. Considering the requirements of electronic devices for insulation and heat dissipation, select modified polyvinyl chloride with good insulation performance and certain heat dissipation ability as the plastic coating material, and add 0.3% ultraviolet stabilizer, 0.2% hindered phenol antioxidant, and 8% aluminum hydroxide flame retardant. Mix the plastic coating material and additives in a high-speed mixer at a speed of 800 r / min for 10 minutes to ensure uniform dispersion of the additives. Granulate the mixed material through a twin-screw extruder. Set the barrel temperature of the extruder from the hopper to the head at 160°C, 170°C, 180°C, and 190°C in sequence, control the screw speed at 150 r / min. After the strip extruded from the die head is air-cooled, cut it into particles with a particle size of 2 mm using a granulator. Place the granulated plastic coating particles in a drying oven with the temperature set at 50°C and the drying time of 2 hours. During the drying process, use a circulating air system to make the temperature in the oven uniform. Seal and store the dried particles in time. Due to the complex shape of the heat sink, select an injection molding machine for plastic coating molding. Add the dried plastic coating particles to the hopper of the injection molding machine. Set the barrel temperature according to the characteristics of the modified polyvinyl chloride at 180 - 210°C, gradually increasing from the hopper to the head, and melt the plastic coating material into a good flowing state through the heating system. Place the pretreated heat sink accurately in the injection mold. Control the injection pressure at 50 MPa and the injection time at 12 seconds to ensure that the plastic coating material uniformly wraps the heat sink. Set cooling water channels in the mold with the cooling medium being circulating water and control the water temperature at 15°C. Determine the cooling time as 20 seconds according to the thickness and material of the heat sink to quickly cool and cure the plastic coating layer and tightly combine it with the heat sink. Conduct an appearance inspection on the plastic-coated heat sink, carefully check whether there are defects such as bubbles, cracks, impurities, and flow marks on the surface of the plastic coating layer. Find a small bubble and make a mark. Use measuring tools such as calipers and projectors to measure the key dimensions of the heat sink, including thickness, hole diameter, etc., to ensure that the dimensional error is controlled within ±0.Within 5 mm, upon measurement, all dimensions meet the design requirements. Touch the plastic coating by hand to feel its hardness and smoothness, and preliminarily judge that the physical properties are normal. Conduct a simple insulation performance test on the heat sink, and no leakage is found. Eject the heat sink from the mold through the ejection device of the injection mold. During the ejection process, strictly control the ejection speed and ejection force to avoid damaging the product. Place the demolded heat sink in an oven with the oven temperature set at 80 °C and the annealing time of 30 minutes. When annealing, place the heat sinks evenly to avoid mutual extrusion to ensure uniform annealing effect. First, use coarse sandpaper with 120 meshes to polish the heat sink to remove some minor surface defects, then use fine sandpaper with 400 meshes for fine polishing, and then use a wool wheel with polishing wax for polishing treatment to make the surface roughness of the product reach Ra 0.8 μm and improve the appearance quality. Clean the heat sink by combining ultrasonic cleaning and rinsing with clean water. First, place it in an ultrasonic cleaning tank containing an appropriate amount of cleaning agent, set the ultrasonic frequency at 30 kHz, and clean for 10 minutes to make the impurities fully detach from the product surface, and then rinse with running clean water to ensure that there is no cleaning agent residue on the surface. Finally, blow dry the surface moisture with compressed air. Check the appearance of the heat sink in detail again to ensure that the surface has no defects, the color is uniform, and the gloss meets the requirements. Use a color difference meter and a gloss meter for quantitative detection and compare with the standard sample, and all indicators meet the standards. Use a high-precision measuring instrument, such as a coordinate measuring machine, to measure the key dimensions of the heat sink again, and control the measurement error within ±0.05 mm. Upon measurement, all dimensions are within the allowable error range. Use the cross-cut method to test the adhesion between the plastic coating and the substrate. Use a knife to cut out a grid of a certain specification, then stick and quickly tear off the tape, and observe the peeling situation of the plastic coating in the grid area. The result shows that the adhesion reaches level 1. Conduct a comprehensive performance test on the heat sink, including insulation performance test, corrosion resistance test, and heat dissipation performance test under the simulated working environment of electronic equipment. The test results show that all performances meet the use requirements of the heat sink for electronic equipment. Select an anti-static plastic film to package the heat sink to prevent damage caused by static electricity during subsequent transportation and storage. Since the heat sink is small in volume, use a single-packaging method. Place the heat sinks neatly into a plastic film bag to ensure tight packaging, and clearly mark information such as product name, specification, model, production date, batch number, shelf life, and usage precautions on the plastic film bag. The marking content uses a clear and non-fading printing method.

[0128] Example 2:

[0129] S1. Raw material preparation;

[0130] S1-1. The part substrate is made of aluminum alloy with a relatively smooth surface. Directly use sandpaper with 250 meshes to polish it to increase the surface roughness;

[0131] S1-2. Prepare an alkaline degreasing agent solution with a concentration of 6%. Immerse the polished parts completely in it, maintain the solution temperature at 42°C, and at the same time turn on ultrasonic assistance for degreasing at a frequency of 25 kHz for 16 minutes. After degreasing, rinse with a large amount of flowing clean water to ensure that the degreasing agent is completely removed;

[0132] S1-3. Prepare a solution containing 3% hydrofluoric acid. Immerse the degreased parts in this solution for 3 minutes, quickly rinse with deionized water after treatment, and then dry with nitrogen;

[0133] S1-4. Select an epoxy resin primer and spray it evenly on the surface of the activated parts through a spray gun. Control the spray gun pressure at 0.35 MPa and the distance between the spray gun and the part surface at 16 cm. After spraying, put the parts into an oven with a set temperature of 62°C and dry for 13 minutes to cure the primer.

[0134] S2. Preparation of the plastic coating material;

[0135] S2-1. According to the special environment in the engine compartment and the requirements of the parts for flexibility, wear resistance and high temperature resistance, select a thermoplastic elastomer as the plastic coating material;

[0136] S2-2. Add 0.4% benzophenone ultraviolet stabilizer, 0.25% antioxidant, and 10% phosphorus-based flame retardant. Stir the plastic coating material and the additives in a high-speed mixer at 950 r / min for 13 minutes;

[0137] S2-3. Granulate the mixed material through a twin-screw extruder. The temperature of the extruder barrel is set from the hopper to the die head at 162°C, 172°C, 182°C, and 192°C in sequence. Control the screw speed at 150 r / min. After the strip extruded from the die head is air-cooled, cut it into particles with a particle size of 2.5 mm by a pelletizer;

[0138] S2-4. Put the granulated plastic coating particles into a drying oven. Set the drying oven temperature at 52°C and dry for 2.2 hours with the assistance of circulating air. After drying, store them sealed.

[0139] S3. Plastic coating forming;

[0140] S3-1. Due to the complex shape of the parts, use an injection molding machine for forming;

[0141] S3-2. Add the dried plastic coating particles to the hopper of the injection molding machine. The temperature of the barrel is set at 185 - 210°C according to the setting, gradually increasing from the hopper to the die head, and melt the plastic coating material into a good flowing state through the heating system;

[0142] S3-3. Place the pre-treated parts in the injection mold, control the injection pressure at 65 MPa, and the injection time at 18 seconds;

[0143] S3-4. Set up cooling water channels in the mold. The cooling medium is circulating water, the water temperature is controlled at 16 °C, and the cooling time is determined to be 35 seconds according to the thickness and material of the component.

[0144] S4. Preliminary quality inspection;

[0145] S4-1. During the inspection, a slight flow mark was found and immediately marked and recorded for subsequent analysis and processing;

[0146] S4-2. During measurement, a dimensional deviation was found to exceed the allowable range. Subsequently, the mold was inspected and it was found that it was caused by slight wear of the mold. The mold was adjusted in time and production was restarted;

[0147] S4-3. Touch the plastic coating by hand to feel its hardness and smoothness, and initially judge that the physical properties are normal. Conduct a simple flexibility test on the component, such as bending the component moderately and observing whether there are abnormal conditions such as cracking in the plastic coating. After testing, it is initially judged that the performance is normal.

[0148] S5. Product processing;

[0149] S5-1. Eject the component from the mold through the ejection device of the injection mold. During the ejection process, strictly control the ejection speed and ejection force to avoid damaging the product;

[0150] S5-2. Put the demolded component into the oven. The oven temperature is set at 82 °C and the annealing time is 35 minutes. During annealing, the components are placed evenly to avoid mutual extrusion to ensure uniform annealing effect;

[0151] S5-3. First, use 180-mesh sandpaper to polish the component to remove some minor surface defects and unevenness, then gradually replace it with 500-mesh fine sandpaper for fine polishing to further improve the surface smoothness. Finally, use a sponge wheel with polishing wax for polishing treatment to make the surface roughness of the product reach Ra1.2 μm;

[0152] S5-4. Put the component into an ultrasonic cleaning tank containing an appropriate amount of cleaning agent. The ultrasonic frequency is set at 35 kHz and the cleaning time is 13 minutes. Use the vibration of ultrasonic waves to make the impurities fully separate from the product surface. After cleaning, rinse the component with flowing water.

[0153] S6. Final quality inspection;

[0154] S6-1. Conduct a detailed inspection of the appearance of the component again to ensure that the surface has no defects, the color is uniform, and the glossiness meets the requirements of the standard sample. Use a color difference meter to quantitatively detect the color of the product, use a glossiness meter to detect the glossiness, and compare it with the standard sample. All indicators meet high standards.

[0155] S6-2. Re-measure the key dimensions of the components using a high-precision three-coordinate measuring instrument, strictly controlling the measurement error within ±0.05 mm. After measurement, all dimensions are within the allowable error range, and the product dimension accuracy meets the requirements.

[0156] S6-3. Use a dedicated tensile testing machine to peel the plastic coating from the substrate and measure the tensile force during the peeling process. The peeling strength is required to be greater than 10 N / cm. After testing, the peeling strength of the plastic coating and the substrate of this component meets the requirements, ensuring a firm bond between the plastic coating and the substrate.

[0157] S6-4. Conduct a comprehensive performance test on the components, test the performance changes of the components after long-term use in a high-temperature environment, and at the same time test their mechanical properties such as tensile strength and impact strength. The results of all performance tests show that the product meets the usage requirements.

[0158] S7. Packaging.

[0159] S7-1. Select an anti-static bubble bag as the packaging material, which can not only prevent static electricity from damaging the components but also provide a certain degree of cushioning protection.

[0160] S7-2. Adopt the single-packaging method, carefully place the components into the anti-static bubble bag to ensure that the components are well fixed in the bag, avoiding shaking and collision during transportation, and then put the packaged components into a carton to further protect the product.

[0161] S7-3. Clearly label the product name, specifications, model, production date, batch number, shelf life, and installation and usage precautions on the outer packaging of the carton. The labeling content is printed in a clear and non-fading manner to ensure that the information is accurate and easy to identify, facilitating subsequent storage, transportation, and usage management.

[0162] Specific steps: The component substrate is made of aluminum alloy with a relatively smooth surface. Directly use 250-mesh sandpaper to polish it to increase the surface roughness. Prepare an alkaline degreasing agent solution with a concentration of 6%. Immerse the polished components completely in it. Keep the solution temperature at 42°C, and at the same time, turn on ultrasonic-assisted degreasing with a frequency of 25 kHz for 16 minutes. After degreasing, rinse with a large amount of flowing clean water to ensure that the degreasing agent is completely removed. Prepare a solution containing 3% hydrofluoric acid, immerse the degreased components in this solution for 3 minutes, quickly rinse with deionized water after treatment, and then dry with nitrogen. Select an epoxy resin primer and spray it evenly on the surface of the activated components through a spray gun. Control the spray gun pressure at 0.35 MPa and the distance between the spray gun and the component surface at 16 cm. After spraying, put the components into an oven with a set temperature of 62°C and dry for 13 minutes to cure the primer. According to the special environment in the engine compartment and the requirements of the components for flexibility, wear resistance, and high-temperature resistance, select a thermoplastic elastomer as the plastic coating material, add 0.4% benzophenone ultraviolet stabilizer, 0.25% antioxidant, and 10% phosphorus-based flame retardant. Stir the plastic coating material and additives in a high-speed mixer at 950 r / min for 13 minutes. Granulate the mixed material through a twin-screw extruder. The barrel temperature of the extruder is set from the hopper to the die head as 162°C, 172°C, 182°C, and 192°C in sequence, and the screw speed is controlled at 150 r / min. The strip-shaped material extruded from the die head is cooled by air and then cut into particles with a particle size of 2.5 mm by a granulator. Put the granulated plastic coating particles into a drying oven, and set the drying oven temperature at 52°C for drying for 2.2 hours, assisted by circulating air, stored sealed after drying. Due to the complex shape of the parts, they are formed by an injection molding machine. Add the dried plastic-coated particles to the hopper of the injection molding machine. The barrel temperature is set at 185 - 210 °C, gradually increasing from the hopper to the head. The plastic-coated material is melted into a good flow state through the heating system. Place the pre-treated parts in the injection mold. The injection pressure is controlled at 65 MPa, and the injection time is 18 seconds. Set cooling water channels in the mold, with the cooling medium being circulating water and the water temperature controlled at 16 °C. The cooling time is determined to be 35 seconds according to the thickness and material of the parts. During the inspection, a slight flow mark was found and immediately marked and recorded for subsequent analysis and processing. During the measurement, it was found that one dimension deviation exceeded the allowable range. Subsequently, the mold was inspected and it was found that it was caused by slight wear of the mold. The mold was adjusted in time and production was restarted. Touch the plastic-coated layer by hand to feel its hardness and smoothness, and initially judge that the physical properties are normal. Conduct a simple flexibility test on the parts, such as bending the parts moderately and observing whether there are abnormal situations such as cracking in the plastic-coated layer. After testing, it is initially judged that the performance is normal. Eject the parts from the mold through the ejection device of the injection mold. Strictly control the ejection speed and ejection force during the ejection process to avoid damaging the product. Place the ejected parts in an oven with the oven temperature set at 82 °C and the annealing time of 35 minutes. Place the parts evenly during annealing to avoid mutual extrusion to ensure uniform annealing effect. First, use 180-mesh sandpaper to polish the parts to remove some minor defects and unevenness on the surface, and then gradually replace it with 500-mesh fine sandpaper for fine polishing to further improve the surface smoothness. Finally, use a sponge wheel with polishing wax for polishing treatment to make the surface roughness of the product reach Ra1.2 μm. Place the parts in an ultrasonic cleaning tank containing an appropriate amount of cleaning agent, with the ultrasonic frequency set at 35 kHz and the cleaning time of 13 minutes. Use the vibration of ultrasonic waves to make the impurities fully detach from the product surface. After cleaning, rinse the parts with flowing water. Check the appearance of the parts in detail again to ensure that the surface has no defects, the color is uniform, and the glossiness meets the requirements of the standard sample. Use a color difference meter to quantitatively detect the color of the product, use a glossiness meter to detect the glossiness, and compare it with the standard sample. All indicators meet high standards. Use a high-precision three-coordinate measuring instrument to measure the key dimensions of the parts again, and strictly control the measurement error within ±0.Within 0.05 mm, upon measurement, all dimensions are within the allowable error range, and the product size accuracy meets the requirements. Using a dedicated tensile testing machine, the plastic coating is peeled off from the substrate, and the tensile force during the peeling process is measured. The required peeling strength is greater than 10 N / cm. After testing, the peeling strength between the plastic coating and the substrate of this component meets the requirements, ensuring a firm bond between the plastic coating and the substrate. Comprehensive performance tests are carried out on the component to test the performance changes of the component after long-term use in a high-temperature environment. At the same time, its mechanical properties such as tensile strength and impact strength are tested. The results of all performance tests indicate that the product meets the usage requirements. An anti-static bubble bag is selected as the packaging material, which can not only prevent static electricity from damaging the component but also provide a certain degree of buffer protection. In a single-packaging method, the component is carefully placed into the anti-static bubble bag to ensure that the component is well-fixed in the bag and avoid shaking and collision during transportation. Then, the packaged component is put into a paper box to further protect the product. Information such as the name, specification, model, production date, batch number, shelf life, and installation and usage precautions of the product are clearly marked on the outer packaging of the paper box. The marked content is printed in a clear and non-fading manner to ensure that the information is accurate and easy to identify, facilitating subsequent storage, transportation, and usage management.

[0163] Although the embodiments of the present invention have been shown and described, for those of ordinary skill in the art, it can be understood that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A novel integrated plastic coating manufacturing process, characterized in that, It includes the following steps: S1. Substrate pretreatment; S2. Preparation of plastic coating material; S3. Plastic coating forming; S4. Preliminary quality inspection; S5. Product treatment; S6. Final quality inspection; S7. Packaging.

2. The novel integrated plastic coating manufacturing process according to claim 1, characterized in that: The specific methods in the step of S1, substrate pretreatment, are as follows: S1-1. For metal substrates such as steel and aluminum alloy, according to the initial surface roughness situation, select sandpaper or grinding wheel with appropriate grit for mechanical grinding. For the relatively rough steel substrate, first use coarse sandpaper with 80-120 mesh to remove impurities such as rust and scale on the surface, and then sequentially replace with 200-400 mesh sandpaper for fine grinding until the surface roughness reaches Ra3.2-Ra6.3μm. For the relatively smooth aluminum alloy substrate, directly use sandpaper with 200-300 mesh to grind to enhance the surface roughness; S1-2. Put the ground substrate into a degreasing agent solution for degreasing treatment. The degreasing agent can be an alkaline degreasing agent, whose main components are sodium hydroxide, sodium carbonate and surfactant, and the concentration is controlled between 5% and 10%. During the degreasing treatment, the solution temperature is maintained at 40-50°C, and the treatment time is 15-20 minutes. During the treatment process, ultrasonic assistance can be used for degreasing, and the ultrasonic frequency is set at 20-40kHz. After degreasing, thoroughly rinse the surface of the substrate with flowing water to remove the residual degreasing agent; S1-3. Adopt chemical corrosion method to conduct surface activation treatment on the degreased substrate. For the steel substrate, immerse it in a solution containing 5%-8% hydrochloric acid for 3-5 minutes to form a microscopic concave-convex structure on the surface of the substrate. For the aluminum alloy substrate, use a solution containing 2%-5% hydrofluoric acid for activation treatment, and the immersion time is controlled within 2-4 minutes. After the treatment, quickly rinse the substrate with deionized water, and then dry the surface moisture with nitrogen; S1-4. Uniformly spray a layer of primer on the surface of the activated substrate. The primer can be an epoxy resin-based primer. When spraying, control the pressure of the spray gun at 0.3-0.5MPa, and keep the distance between the spray gun and the substrate surface at 15-20cm to ensure uniform coverage of the primer. After spraying, put the substrate into an oven and dry it at a temperature of 60-70°C for 10-15 minutes to cure the primer.

3. A novel one-piece plastic coating manufacturing process according to claim 1, characterized in that: The specific methods in the step of S2, preparation of plastic coating material, are as follows: S2-1. Reasonably select the plastic coating material according to the use environment and performance requirements of the product. In the field of chemical equipment that requires chemical corrosion resistance, give priority to using polytetrafluoroethylene or polyvinylidene fluoride. In the field of mechanical parts that require good flexibility and wear resistance, thermoplastic elastomer can be selected. In the general protective packaging field, polyethylene or polyvinyl chloride can be chosen; S2-2. Add an appropriate amount of functional additives to the selected plastic-coated material. For products to be used outdoors, add 0.3% - 0.6% of ultraviolet stabilizers, such as benzophenone-based or benzotriazole-based compounds, to improve the weather resistance of the product, and add 0.2% - 0.5% of antioxidants, such as hindered phenol antioxidants, to prevent the material from oxidative degradation during processing and use. If the product has flame retardant requirements, add 5% - 15% of flame retardants according to the flame retardant grade, such as inorganic flame retardants like aluminum hydroxide and magnesium hydroxide, or phosphorus-based and halogen-based organic flame retardants. Thoroughly mix the plastic-coated material and the additives in a high-speed mixer, set the stirring speed at 800 - 1000 r / min, and the stirring time at 10 - 15 minutes to ensure that the additives are evenly dispersed in the plastic-coated material. S2-3. Granulate the mixed material through a twin-screw extruder. The temperature of the extruder barrel is set from the hopper to the die head as 160 - 170 °C, 170 - 180 °C, 180 - 190 °C, 190 - 200 °C in sequence, and the screw speed is controlled at 150 - 200 r / min. During granulation, the strip-shaped material extruded through the die head is cooled by water or air and then cut into uniform particles by a pelletizer. The particle size is controlled between 2 - 4 mm. S2-4. Put the granulated plastic-coated particles into a drying oven for drying treatment to remove the moisture adsorbed on the particle surface. Set the temperature of the drying oven at 50 - 60 °C, and the drying time at 2 - 3 hours. The dried particles should be sealed and stored in time.

4. A novel one-piece plastic coating manufacturing process according to claim 1, characterized in that: The basic principle in the S3. Plastic coating and molding step is as follows: S3-1. Select appropriate plastic coating and molding equipment according to the shape and size of the product. For pipe products, such as wires and cables, water pipes, etc., use an extruder for plastic coating and molding. For parts with complex shapes, such as automotive interior parts, electronic device casings, etc., use an injection molding machine for molding. For large containers or hollow products, such as plastic buckets, toy balls, etc., select a blow molding machine for processing. S3-2. Add the dried plastic-coated particles into the hopper of the corresponding molding equipment. For an injection molding machine, the barrel temperature is set according to the characteristics of the selected plastic-coated material. For example, the barrel temperature of polyvinyl chloride is generally 180 - 220 °C, gradually increasing from the hopper to the die head. For an extruder, the barrel temperature is set between 170 - 210 °C, and the temperature of the blow molding machine is adjusted according to specific process requirements, generally in the range of 160 - 200 °C. Gradually melt the plastic-coated material through the heating system to reach a good flow state. S3-3. Add the dried plastic-coated particles into the hopper of the corresponding molding equipment. For an injection molding machine, the barrel temperature is set according to the characteristics of the selected plastic-coated material. For example, the barrel temperature of polyvinyl chloride is generally 180 - 220 °C, gradually increasing from the hopper to the die head. For an extruder, the barrel temperature is set between 170 - 210 °C, and the temperature of the blow molding machine is adjusted according to specific process requirements, generally in the range of 160 - 200 °C. Gradually melt the plastic-coated material through the heating system to reach a good flow state. S3-4. During the plastic coating forming process, a cooling device is used to cool and shape the formed product. The cooling medium is usually circulating water, and the water temperature is controlled at 15 - 25°C. For injection-molded products, cooling channels are set in the mold, and heat is carried away by the circulating water. The cooling time is determined according to the thickness and material of the product, generally 10 - 60 seconds. For extrusion-molded products, a cooling water tank is set at the die head to quickly cool the plastic-coated product after extrusion. For blow-molded products, cooling air ducts are set on the mold surface for air cooling, and the cooling air speed is controlled at 3 - 5 m / s. During the cooling process, the flow rate and temperature distribution of the cooling medium can be reasonably adjusted according to the shape and size of the product to ensure uniform cooling and solidification of the plastic coating layer and tight bonding with the substrate.

5. A novel one-piece plastic coating manufacturing process according to claim 1, characterized in that: The specific method in the described S4, preliminary quality inspection step, is as follows: S4-1. Conduct an appearance inspection on the product after plastic coating forming. Carefully check whether there are defects such as bubbles, cracks, impurities, flow marks, etc. on the surface of the plastic coating layer. For the detected minor defects, mark and record them in a timely manner. S4-2. Use measuring tools such as calipers, micrometers, projectors, etc. to measure the key dimensions of the product, including length, width, thickness, hole diameter, etc. Compare the measurement results with the design dimensions to ensure that the product size error is controlled within ±0.5 mm. For products with size deviations beyond the allowable range, analyze the reasons and make corresponding adjustments, such as checking whether the mold is worn and whether the forming process parameters are appropriate. S4-3. Conduct a simple performance evaluation on the product. Feel the hardness and smoothness of the plastic coating layer by hand to preliminarily judge whether its physical properties are normal. For some products with special performance requirements, such as the insulation performance of wire and cable and the pressure resistance performance of pipes, conduct preliminary functional tests to timely detect potential quality problems.

6. A novel one-piece plastic coating manufacturing process according to claim 1, characterized in that: The specific method in the described S5, product treatment step, is as follows: S5-1. For injection-molded products, eject the product from the mold through the ejection device of the mold. During the ejection process, pay attention to controlling the ejection speed and ejection force to avoid damaging the product. For extrusion-molded and blow-molded products, carefully take out the product from the mold or equipment to ensure that the plastic coating layer is not scratched or collided. S5-2. Put the demolded product into an oven for annealing treatment. The oven temperature is set at 80 - 90°C, and the annealing time is 30 - 60 minutes. During the annealing process, the products should be evenly placed in the oven to avoid mutual extrusion and ensure uniform annealing effect. S5-3. Conduct surface treatment on the annealed product. First, use sandpaper for grinding. According to the roughness and requirements of the product surface, select sandpaper with appropriate grit. Start with coarse sandpaper of 120 - 200 mesh, and gradually replace it with fine sandpaper of 400 - 800 mesh for fine grinding to remove surface defects and unevenness. Then, use a polishing wheel for polishing treatment. The polishing wheel can be a wool wheel or a sponge wheel, and operate with polishing wax to make the surface roughness of the product reach Ra0.8 - Ra1.6 μm, presenting a smooth and bright appearance. S5-4. Clean the surface-treated product. The cleaning method can be a combination of ultrasonic cleaning and rinsing with clean water. First, place the product in an ultrasonic cleaning tank containing an appropriate amount of cleaning agent. Set the ultrasonic frequency to 30 - 50 kHz and the cleaning time to 10 - 15 minutes to allow impurities to fully detach from the product surface. Then, rinse the product with flowing clean water to ensure no cleaning agent residue on the surface. Finally, dry the moisture on the product surface with compressed air.

7. A novel one-piece plastic coating manufacturing process according to claim 1, characterized in that: The specific method in the described S6. Final quality inspection step is as follows: S6-1. Conduct a detailed inspection of the product's appearance again to ensure there are no defects on the surface, the color is uniform, and the glossiness meets the requirements. Use professional appearance inspection equipment, such as a color difference meter, glossiness meter, etc., to quantitatively detect the color and glossiness of the product and compare it with the standard sample to ensure that the product's appearance quality reaches a high standard. S6-2. Use high-precision measuring instruments to measure the key dimensions of the product again. For products with high dimensional accuracy requirements, a coordinate measuring machine can be used for measurement, and the measurement error is controlled within ±0.05 mm. If any dimensional deviation is found, analyze the reason and adjust or scrap the product. S6-3. Use the cross-cut method or peel test to test the adhesion between the plastic coating and the substrate. Use a tool to cut a grid of a certain specification, then stick and quickly tear off the tape, and observe the peeling situation of the plastic coating in the grid area. According to the standard rating, the adhesion is required to reach level 1 - 2. The peel test is to use a special tensile testing machine to peel the plastic coating from the substrate and measure the tensile force during the peeling process. The peel strength is required to be greater than 10 N / cm to ensure a firm bond between the plastic coating and the substrate. S6-4. According to the usage requirements of the product, conduct comprehensive tests on various performances of the product. For corrosion-resistant products, conduct a chemical corrosion test by immersing the product in a specific chemical medium and observing the corrosion situation of the plastic coating after a certain period. For weather-resistant products, conduct an artificial accelerated aging test to simulate environmental conditions such as sunlight, temperature, and humidity outdoors and test the performance changes of the product after a certain period. Test the mechanical properties such as tensile strength, impact strength, and bending strength of the product to ensure that the product performance meets the actual usage requirements.

8. A novel one-piece plastic coating manufacturing process according to claim 1, characterized in that: The specific method in the described S7. Packaging step is as follows: S7-1. Select moisture-proof and anti-static packaging materials to package the product, such as moisture-proof plastic bags, anti-static bubble bags, cardboard boxes, etc. For some precision products or products sensitive to static electricity, give priority to using anti-static packaging materials. S7-2. Design a suitable packaging method according to the shape and size of the product. For small products, single packaging or combined packaging of multiple products can be used. Place the product in a plastic bag or cardboard box and add an appropriate amount of cushioning materials, such as foam plastics, sponges, etc. For large products, winding packaging or wooden box packaging can be used. S7-3. Clearly label the product name, specifications, model number, production date, batch number, shelf life, usage precautions and other information on the outer packaging of the product. The labeling content should be printed in a clear and non-fading manner to ensure that the information is accurate and easy to identify.

9. A novel one-piece plastic coating manufacturing process according to claim 3, characterized in that: In the step S2-4, during the drying process, a circulating air system can be adopted.