Surface treatment process for single-color injection molded part to present electroplating and high-brightness black paint effects

Abstract

The invention discloses a surface treatment process for presenting electroplating and high-brightness black paint effects on a single-color injection molded part, and relates to the technical field of surface treatment of injection molded parts. A first front protection layer is formed by spraying UV primer on the upper surface of the material layer; forming a metal film layer on the upper surface of the first front protection layer through magnetron sputtering; uV coating is sprayed on the surface of the second front protective layer, and then a laser etching means is adopted to remove the third front protective layer and the metal film layer covering the third front protective layer according to a set pattern to form a highly black and bright pattern area. According to the surface treatment process, the surface treatment process setting that five protective layers are adopted for the single-color injection molding part is adopted, the material layer and the multiple film layers are combined with one another, and laser etching is utilized, so that coexistence of metal electroplating patterns and high-brightness black paint is presented on the single-color injection molding part, and the surface treatment process of shocking vision is formed; and the appearance design requirements of automobile interior and exterior ornaments are met.

Description

Technical Field

[0001] The invention relates to the technical field of surface treatment of injection molded parts, in particular to a surface treatment process for monochrome injection molded parts presenting electroplating and high-gloss black paint effects. Background Art

[0002] With the diversification and personalization of automotive interior and exterior trims, automotive exterior trims have been given more changes. PVD coating technology is added to the exterior trim to embellish it and increase the sense of color. For existing technology, the material can only present a single color after painting.

[0003] The Chinese invention patent application with publication number CN106958030A discloses a plastic electroplating method and an electroplated plastic part, wherein a plastic electroplating method is disclosed, comprising: preparing a color-platable plastic mold using a plateable plastic material having a preset color; plating a metal layer on the upper surface of the color-platable plastic mold, and etching the surface of the metal layer to obtain a preset pattern, wherein the bottom surface of the hollowed-out portion of the preset pattern is the upper surface of the color-platable plastic mold. By preparing a color-platable plastic mold using a color-platable plastic material having a preset color, and forming a metal layer and a preset pattern on the upper surface of the color-platable plastic mold, that is, by etching the metal layer to expose the surface of the color-platable plastic mold, when applied to automotive interior parts, the light-guiding requirements are achieved, and a beacon function with different colors can also be achieved.

[0004] The above electroplating process can only present a single electroplating layer color when static, and cannot achieve the combined effect of electroplating and high-gloss black paint pattern. Summary of the invention

[0005] In order to solve the technical problem that the existing products of automobile interior and exterior decoration parts have a single static color, the present invention provides a surface treatment process for monochrome injection molded parts to present electroplating and high-gloss black paint effects. The following technical solutions are adopted:

[0006] The surface treatment process of monochrome injection molding presents electroplating and high-gloss black paint effects, which is used to produce automobile interior decoration parts with two surface effects of electroplating and high-gloss black paint. The automobile interior decoration parts include a material layer, a first front protective layer, a second front protective layer, a third front protective layer and a fourth front protective layer arranged in sequence from bottom to top, and the third front protective layer and the second front protective layer adopt a laser engraving process to form a high-gloss black pattern area;

[0007] The surface treatment process of automotive interior parts includes the following steps:

[0008] Step 1, obtaining a high gloss black material layer by injection molding;

[0009] Step 2, the first front protective layer is a UV primer coating, and the first front protective layer is formed by spraying a UV primer on the upper surface of the material layer;

[0010] Step 3, the second front protective layer is a metal film layer, and the metal film layer is formed on the upper surface of the first front protective layer by magnetron sputtering;

[0011] Step 4: The third front protective layer is a UV intermediate paint coating, which is formed by spraying UV paint on the surface of the second front protective layer, and then using laser engraving to remove the third front protective layer and the metal film layer covering the bottom according to the set pattern to form a high black and bright pattern area;

[0012] Step 5, the fourth front protective layer is a PU topcoat coating, which is formed by spraying a colorless transparent topcoat on the surface of the fourth front protective layer.

[0013] By adopting the above technical scheme, a surface treatment process setting of five protective layers is adopted for monochrome injection molded parts, a material layer and multiple film layers are combined with each other in the film layer structure, and laser engraving is used to achieve the coexistence of metal electroplating patterns and high-gloss black paint on monochrome injection molded parts, forming a visually stunning surface treatment process, which meets the appearance design requirements of automotive interior and exterior trims.

[0014] Optionally, the material layer is made of PC plus black glossy ABS material and is formed by injection molding.

[0015] By adopting the above technical solution, the high-gloss black ABS material of the material layer can pass through the pattern area to form a visual effect of a high-gloss black pattern area.

[0016] Optionally, in step 2, the thickness of the UV primer coating of the first front protective layer is controlled between 15 μm and 25 μm, and UV lamp irradiation is performed, the UV lamp energy is 1000MJc㎡ / 200MWc㎡, and the line speed is 40±5r / Hz.

[0017] By adopting the above technical solution, a 15μm-25 thick UV primer coating is applied, and then UV light irradiation is performed under the conditions of V lamp energy of 1000MJc㎡ / 200MWc㎡ and line speed of 40±5r / Hz to form a stable protective layer on the surface of the material layer.

[0018] Optionally, in step 3, the metal film layer is a chromium film layer, a gold film layer, a silver film layer, an indium film layer or a copper film layer, and the thickness of the metal film layer is controlled between 20nm and 30nm.

[0019] By adopting the above technical solution, the metal film layer can be selected according to the specific design, and combined with the high black and bright pattern effect, different two-color visual effects can be presented.

[0020] Optionally, after the metal film layer is completed in step 3, the third front protection layer is completed within twelve hours.

[0021] By adopting the above technical solution, in order to prevent the oxidation of the metal film layer from affecting the visual effect, the third front protective layer needs to be completed within twelve hours. After the laser engraving method is completed to remove the third front protective layer and the metal film layer underneath according to the set pattern to form a high black and bright pattern area, the UV coating of the third front protective layer in the unremoved part can still protect the metal film layer.

[0022] Optionally, the UV coating thickness of the third front protective layer is controlled between 15 μm and 25 μm, and UV lamp is used for irradiation, with the UV lamp energy of 1000MJc㎡ / 200MWc㎡ and the line speed of 40±5r / Hz.

[0023] Optionally, the PU topcoat coating thickness of the fourth front protective layer is controlled between 40 μm and 50 μm, the drying oven temperature is 70 degrees, and the line speed is 40±5 r / Hz.

[0024] By adopting the above technical solution, the oven temperature is one of the important factors affecting the quality of black shading paint spraying:

[0025] Cure Speed: The higher the oven temperature, the faster the coating cures. This helps speed up production, especially on continuous production lines.

[0026] Coating quality: The drying oven temperature can affect the leveling and drying degree of the coating. The appropriate temperature can ensure that the coating is uniform and smooth without defects such as pinholes and sagging.

[0027] Coating performance: Too high a temperature may cause excessive internal stress in the coating, affecting the adhesion and durability of the coating. Too low a temperature may cause the coating to not dry sufficiently, affecting its performance.

[0028] Environmental protection and energy consumption: Higher drying oven temperature may increase energy consumption, and also generate more waste gas and waste heat, which will have an impact on the environment. Therefore, it is necessary to comprehensively consider the impact of temperature on coating performance and environmental protection.

[0029] Using a drying oven temperature of 70 degrees and a line speed of 40±5r / Hz can form a more stable PU topcoat coating.

[0030] In summary, the present invention includes at least one of the following beneficial technical effects:

[0031] The present invention can provide a surface treatment process for monochrome injection molded parts to present electroplating and high-gloss black paint effects. The surface treatment process setting adopts a five-layer protective layer for the monochrome injection molded parts, utilizes a material layer and a plurality of film layers combined with each other in a film layer structure, and utilizes laser engraving to achieve the coexistence of metal electroplating patterns and high-gloss black paint on the monochrome injection molded parts, forming a visually stunning surface treatment process, which meets the appearance design requirements of automobile interior and exterior trims. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 It is a schematic flow chart of the surface treatment process of a single-color injection molded part of the present invention showing electroplating and high-gloss black paint effects;

[0033] Figure 2 It is a schematic diagram of the cross-sectional structure of the automobile interior decoration part of the present invention;

[0034] Explanation of the reference numerals: 1. material layer; 2. first front protective layer; 3. second front protective layer; 31. high gloss pattern area; 4. third front protective layer; 5. fourth front protective layer. DETAILED DESCRIPTION

[0035] The present invention is further described in detail below in conjunction with the accompanying drawings.

[0036] The embodiment of the present invention discloses a surface treatment process for a monochrome injection molded part to present an electroplating and high-gloss black paint effect.

[0037] Reference Figure 1 and Figure 2 , a surface treatment process for monochrome injection molding parts showing electroplating and high-gloss black paint effects, used for manufacturing automotive interior parts with two surface effects of electroplating and high-gloss black paint effects, the automotive interior parts comprising a material layer 1, a first front protective layer 2, a second front protective layer 3, a third front protective layer 4 and a fourth front protective layer 5 are sequentially arranged from bottom to top, and the third front protective layer 4 and the second front protective layer 3 adopt a laser engraving process to form a high-gloss black pattern area 31;

[0038] The surface treatment process of automotive interior parts includes the following steps:

[0039] Step 1, obtaining a high gloss black material layer 1 by injection molding;

[0040] Step 2, the first front protective layer 2 is a UV primer coating, and the first front protective layer 2 is formed by spraying UV primer on the upper surface of the material layer 1;

[0041] Step 3, the second front protection layer 3 is a metal film layer, and the metal film layer is formed on the upper surface of the first front protection layer 2 by magnetron sputtering;

[0042] Step 4, the third front protective layer 4 is a UV intermediate paint coating, which is formed by spraying UV paint on the surface of the second front protective layer 3, and then using laser engraving to remove the third front protective layer 4 and the metal film layer covering the bottom according to the set pattern to form a high black and bright pattern area 31;

[0043] Step 5, the fourth front protective layer 5 is a PU topcoat coating, which is formed by spraying a colorless and transparent topcoat on the surface of the fourth front protective layer 5.

[0044] The surface treatment process uses five protective layers for monochrome injection molded parts. The material layer and multiple film layers are combined with the film layer structure, and laser engraving is used to achieve the coexistence of metal electroplating patterns and high-gloss black paint on monochrome injection molded parts, forming a visually stunning surface treatment process that meets the appearance design requirements of automotive interior and exterior trims.

[0045] The material layer 1 is made of PC and black glossy ABS material and is obtained by injection molding.

[0046] The high gloss ABS material of the material layer 1 can pass through the pattern area to form a visual effect of a high gloss pattern area 31 .

[0047] In step 2, the thickness of the UV primer coating of the first front protective layer 2 is controlled between 15 μm and 25 μm, and UV lamp irradiation is performed, the UV lamp energy is 1000 MJc㎡ / 200 MWc㎡, and the line speed is 40±5 r / Hz.

[0048] After a 15μm-25 thick UV primer coating, a stable protective layer is formed on the surface of the material layer 1 by irradiating with a UV lamp at a V lamp energy of 1000MJc㎡ / 200MWc㎡ and a line speed of 40±5r / Hz.

[0049] In step 3, the metal film layer is a chromium film layer, a gold film layer, a silver film layer, an indium film layer or a copper film layer, and the thickness of the metal film layer is controlled between 20nm and 30nm.

[0050] The metal film layer can be selected according to the specific design, and combined with the high-gloss black pattern effect, it can present different two-color visual effects.

[0051] After the metal film layer is completed in step 3, the third front side protection layer 4 is completed within twelve hours.

[0052] In order to prevent the oxidation of the metal film layer from affecting the visual effect, the third front protective layer 4 needs to be completed within twelve hours. After the laser engraving method is completed to remove the third front protective layer 4 and the metal film layer underneath according to the set pattern to form a high black and bright pattern area 31, the UV coating of the third front protective layer 4 in the unremoved part can still protect the metal film layer.

[0053] The UV coating thickness of the third front protective layer 4 is controlled between 15 μm and 25 μm, and is irradiated with a UV lamp with an energy of 1000 MJc㎡ / 200 MWc㎡ and a line speed of 40±5 r / Hz.

[0054] The thickness of the PU topcoat coating of the fourth front protective layer 5 is controlled between 40 μm and 50 μm, the drying oven temperature is 70 degrees, and the line speed is 40±5 r / Hz.

[0055] The oven temperature is one of the important factors affecting the quality of black paint spraying:

[0056] Cure Speed: The higher the oven temperature, the faster the coating cures. This helps speed up production, especially on continuous production lines.

[0057] Coating quality: The drying oven temperature can affect the leveling and drying degree of the coating. The appropriate temperature can ensure that the coating is uniform and smooth without defects such as pinholes and sagging.

[0058] Coating performance: Too high a temperature may cause excessive internal stress in the coating, affecting the adhesion and durability of the coating. Too low a temperature may cause the coating to not dry sufficiently, affecting its performance.

[0059] Environmental protection and energy consumption: Higher drying oven temperature may increase energy consumption, and also generate more waste gas and waste heat, which will have an impact on the environment. Therefore, it is necessary to comprehensively consider the impact of temperature on coating performance and environmental protection.

[0060] Using a drying oven temperature of 70 degrees and a line speed of 40±5r / Hz can form a more stable PU topcoat coating.

[0061] The following is a specific example to illustrate the implementation principle of the surface treatment process of the present invention for a single-color injection molded part showing electroplating and high-gloss black paint effect:

[0062] The monochrome injection molded parts present the structural coating structure of electroplating and piano black, including the material layer PC+ABS, UV primer layer, chrome film layer, UV color paint layer, and PU topcoat layer. The color is selected according to the application scenario and customer requirements. Here, the thickness of the UV primer layer is between 15um-25μm, the chrome film 2 layer is between 20nm-30nm, the thickness of the UV color paint layer is between 15um-25μm, and the PU topcoat protective layer 4 is colorless and transparent, with a thickness of 40um-50um. It is achieved by spraying.

[0063] like Figure 2 As shown, this patent also provides a process for electroplating and piano black of a single-color injection molded part, and the specific process is as follows:

[0064] Material layer production: The material layer is a transparent material. The material of the material layer is made of PC+ABS (high gloss black), and the material is obtained by injection molding.

[0065] 2. Production of front protective layer 1: The first layer of the front protective layer is a UV primer coating, which is formed on the upper surface of the material layer by spraying. The thickness of the front protective layer is controlled between 15μm-25μm, and the UV lamp is irradiated. The UV lamp energy is 1000MJc㎡ / 200MWc㎡, and the line speed is 40±5r / Hz

[0066] Preparation of the front protective layer 2: The second layer of the front protective layer is a chromium film layer. When it is coated on the upper surface of the material layer by magnetron sputtering, the thickness of the front protective layer is controlled between 20nm and 30nm.

[0067] 4. Production of the front protective layer 3: The third layer of the front protective layer is a UV paint coating. When it is formed on the upper surface of the material layer by spraying, the thickness of the front protective layer is controlled between 15μm-25μm, and it is irradiated with a UV lamp. The UV lamp energy is 1000MJc㎡ / 200MWc㎡, and the line speed is 40±5r / Hz.

[0068] 5. Laser engraving: Use the light-transmitting laser engraving method to remove the second and third layers of chrome film and paint layer according to the LOGO pattern, leaving the pattern with chrome film.

[0069] 6. Production of the front protective layer 4: The fourth layer of the front protective layer is a PU topcoat coating. When it is formed on the upper surface of the material layer by spraying, the thickness of the front protective layer is controlled between 40μm-50μm, the drying oven temperature is 70 degrees, and the line speed is 40±5r / Hz.

[0070] The requirements for the product are as follows:

[0071] Water resistance test:

[0072] Instrument: Constant temperature water bath. Take 3 finished products or 3 150mmx100mm samples and test them according to ASTND870 standard. Immerse three quarters of the sample length in a 40℃ constant temperature water bath for 240 hours. After immersion, let the sample recover at room temperature for 30 minutes, and then check the appearance and attached parts of the sample.

[0073] For bumper paint, the test temperature must be 50℃ and the soaking time must be 3x24=72 hours. After the sample is allowed to recover at room temperature for 30 minutes, check the appearance and adhesion of the sample.

[0074] After the test, the product has no blistering, loss of gloss, softening or other abnormalities, and the adhesion has no change;

[0075] Heat aging test:

[0076] Aging temperature 80, aging time 500H;

[0077] Apparatus: Blast drying oven;

[0078] Take 3 finished products or 3 150mmx100mm samples and conduct high temperature heat aging test according to the conditions in Table 4. After the test, the samples are allowed to recover at room temperature for at least 30 minutes before inspecting their appearance, evaluating the grayscale according to GB / 250, and measuring the gloss of the samples after heat aging according to the requirements of 5.2;

[0079] There is no obvious change in appearance, the grayscale level is ≥4, the gloss loss is <15%, and the adhesion is not weaker than level 1 ((aging temperature 80℃).

[0080] Moisture and heat resistance test:

[0081] 50 degrees temperature, 95% humidity, 336H

[0082] Instrument: high and low temperature test chamber;

[0083] Take 3 finished products or 3 150mmx100mm test specimens, place the specimens in a high and low temperature test chamber at 50℃ and 95% relative humidity for 336h. After the test, place them at room temperature for 30min, evaluate the grayscale according to GB / 250, and conduct 5.5 test;

[0084] No blistering or discoloration, grayscale level ≥ 4, adhesion level not weaker than level 1.

[0085] Condensate immersion test:

[0086] Temperature 38 degrees, humidity 100%, experiment 240 hours;

[0087] Instrument: Condensation water test chamber;

[0088] Take 3 finished products or 3 150mmx100mm specimens, keep them in a condensation water test box at (38±2)℃ and 100% relative humidity for 240h. After the experiment, place them at room temperature for 30min and evaluate the grayscale according to GB / 250.

[0089] No blistering or discoloration, grayscale level ≥ 4, adhesion level not weaker than level 1.

[0090] Light aging test 2000H

[0091] Take 3 samples of 150mmx70mm and conduct the test according to the test method specified in GB / T1865. The test time is 2000h. The lighting conditions are shown in Table 8. After the test, check the appearance, evaluate the grayscale level according to GB / 250, and measure the gloss and color according to Clause 5.2: After the appearance inspection, conduct a 24h water immersion test in a 40℃ constant temperature water tank. After the test, take out the test piece and blow dry it, then draw an X at the center of the test piece and 50mm from the bottom, X^ 30m high and 20m wide, and peel it off with a tape with an adhesive force ≥ (10±1)N / 25mm. The light aging test conditions are shown in Table 1:

[0092] Table 1

[0093]

[0094] There is no abnormal appearance phenomenon such as cracking, powdering, whitening, spots, deformation, etc. The grayscale level is better than level 4, and the gloss change rate is s15%. After water immersion test: scratch adhesion retention rate>95%.

[0095] The above are all preferred embodiments of the present invention, and are not intended to limit the protection scope of the present invention. Therefore, any equivalent changes made based on the structure, shape, and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. The surface treatment process of monochrome injection molded parts presents electroplating and high-gloss black paint effects, characterized by: An automotive interior decoration part for producing two surface effects: electroplating and high-gloss black paint effect, the automotive interior decoration part comprising a material layer (1), a first front protection layer (2), a second front protection layer (3), a third front protection layer (4) and a fourth front protection layer (5) arranged in sequence from bottom to top, wherein the third front protection layer (4) and the second front protection layer (3) are laser engraved to form a pattern area (31); The surface treatment process of automotive interior parts includes the following steps: Step 1, obtaining a high gloss black material layer (1) by injection molding; Step 2, the first front protective layer (2) is a UV primer coating, and the first front protective layer (2) is formed by spraying a UV primer on the upper surface of the material layer (1); Step 3, the second front protective layer (3) is a metal film layer, and the metal film layer is formed on the upper surface of the first front protective layer (2) by magnetron sputtering; Step 4, the third front protective layer (4) is a UV intermediate coating, which is formed by spraying UV coating on the surface of the second front protective layer (3), and then using laser engraving to remove the third front protective layer (4) and the metal film layer covering the bottom according to a set pattern to form a high black and bright pattern area (31); Step 5, the fourth front protective layer (5) is a PU topcoat coating, which is formed by spraying a colorless transparent topcoat on the surface of the fourth front protective layer (5).

2. The surface treatment process for a single-color injection molded part showing an electroplating and high-gloss black paint effect according to claim 1, characterized in that: The material layer (1) is made of PC and black glossy ABS material and is formed by injection molding.

3. The surface treatment process for a single-color injection molded part showing an electroplating and high-gloss black paint effect according to claim 1, characterized in that: In step 2, the thickness of the UV primer coating of the first front protective layer (2) is controlled between 15 μm and 25 μm, and UV lamp irradiation is performed, with the UV lamp energy of 1000 MJc㎡ / 200 MWc㎡ and the line speed of 40±5 r / Hz.

4. The surface treatment process for a single-color injection molded part showing an electroplating and high-gloss black paint effect according to claim 1, characterized in that: In step 3, the metal film layer is a chromium film layer, a gold film layer, a silver film layer, an indium film layer or a copper film layer, and the thickness of the metal film layer is controlled between 20nm and 30nm.

5. The surface treatment process for a single-color injection molded part showing an electroplating and high-gloss black paint effect according to claim 1, characterized in that: After the metal film layer is completed in step 3, the third front protection layer (4) is completed within twelve hours.

6. The surface treatment process for a single-color injection molded part showing an electroplating and high-gloss black paint effect according to claim 1, characterized in that: The thickness of the UV coating of the third front protective layer (4) is controlled between 15 μm and 25 μm, and UV lamp irradiation is adopted, the UV lamp energy is 1000 MJc㎡ / 200 MWc㎡, and the line speed is 40±5 r / Hz.

7. The surface treatment process for a single-color injection molded part showing an electroplating and high-gloss black paint effect according to claim 1, characterized in that: The thickness of the fourth front protective layer (5) is controlled between 40 μm and 50 μm, the drying oven temperature is 70 degrees, and the line speed is 40±5 r / Hz.

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