Automobile bumper structure and processing method thereof

Abstract

A car bumper structure, used for mounting at the front and rear ends of a vehicle body and in conjunction with light strips on the vehicle body surface, includes a transparent PP bumper body. The surface of the transparent PP bumper body is sequentially stacked with a transparent primer layer, a laser-engraved layer, a translucent colored paint layer, and a protective paint film layer. The laser-engraved layer has a laser-engraved pattern. The transparent primer layer is composed of the following components by weight percentage: 20-30% chlorinated polyolefin resin, 1-2% polyester phosphate adhesion promoter, 1-3% acrylic modified resin, 25-30% butyl acetate, 25-30% xylene, 13-18% cyclohexanone, and 0.1-0.4% modified polymer leveling agent. A method for processing the above-mentioned car bumper structure is also disclosed.

Description

Technical Field

[0001] This invention relates to the field of automotive parts processing technology, and in particular to an automotive bumper structure and its processing method. Background Technology

[0002] Car bumpers are rod-shaped structures installed at the front and rear of a vehicle. They serve not only a decorative function but also as safety devices that absorb and cushion external impacts, protecting the vehicle body and occupants. To achieve lightweight bumpers, most car bumpers on the market are made of engineering plastics. Currently, the industry primarily uses PP material to ensure the structural strength of the bumper. To enhance the decorative function of car bumpers, they are often coated with layers to provide a specific shape. However, existing car bumper coatings are mostly single-color, resulting in low visibility and failing to meet users' decorative needs. Furthermore, common coatings on the market have insufficient adhesion to PP substrates, causing the coating on the bumper to peel off after a period of use, thus affecting the bumper's appearance. Summary of the Invention

[0003] Therefore, it is necessary to address the above-mentioned shortcomings by providing a car bumper structure with strong coating adhesion and capable of displaying preset patterns, as well as its processing method.

[0004] A car bumper structure is used to be installed at the front and rear of the car body and to cooperate with the light strip on the surface of the car body. The car bumper structure includes a transparent PP bumper body. A transparent primer layer, a laser engraving layer, a light-transmitting color paint layer and a paint film protective layer are stacked on the surface of the transparent PP bumper body in sequence. The laser engraving layer has a laser engraving pattern.

[0005] The transparent primer layer is composed of the following components in the indicated weight percentages: 20-30% chlorinated polyolefin resin, 1-2% polyester phosphate adhesion promoter, 1-3% acrylic modified resin, 25-30% butyl acetate, 25-30% xylene, 13-18% cyclohexanone, and 0.1-0.4% modified polymer leveling agent;

[0006] The laser engraving layer is composed of the following components by weight percentage: 20-35% modified acrylic polyol resin, 1-2% chlorinated polyolefin, 40-60% conductive masking black paste, 3-8% butyl acetate, 5-15% xylene, 3-6% cyclohexanone, and 0-0.8% laser engraving powder;

[0007] The translucent paint layer is composed of the following components by weight percentage: 40-50% saturated polyester, 2-6% butylated amino resin, 8-13% EVA wax, 1-4% CAB resin, 0.5-2% polyamide wax, 15-20% butyl acetate, 5-10% ethyl 3-ethoxypropionate, 0-10% pearlescent powder, and 5-15% color paste;

[0008] The protective coating layer is composed of the following components in the indicated weight percentages: 50-65% hydroxyl acrylic resin, 10-15% anti-sagging resin, 0-6% hydroxyl-containing hyperbranched polyester, 2-4% ethylene glycol butyl ether acetate, 1-4% diethylene glycol butyl ether acetate, 2-4% ethyl 3-ethoxypropionate, 5-8% propylene glycol methyl ether acetate, 8-12% butyl acetate, 0.8-1% light stabilizer, 0.6-0.8% UV absorber, 0.1-0.3% conductive agent, 0.001% drier, 0.08-0.3% polyether-modified polydimethylsiloxane, and 0.3-1% polyacrylate leveling agent.

[0009] In one embodiment, the laser-engraved layer comprises the following components in weight fractions: 20-30% modified acrylic polyol resin, 1-2% chlorinated polyolefin, 50-60% conductive masking paste, 3-8% butyl acetate, 5-10% xylene, 3-6% cyclohexanone, and 0.3-0.8% laser-engraved powder; or

[0010] The laser-engraved layer is composed of the following components by weight fraction: 25-35% modified acrylic polyol resin, 1-2% chlorinated polyolefin, 40-50% conductive masking black paste, 3-8% butyl acetate, 10-15% xylene, and 3-6% cyclohexanone.

[0011] In one embodiment, the translucent paint layer comprises the following components by weight fraction: 40-50% saturated polyester, 2-6% butylated amino resin, 8-13% EVA wax, 1-4% CAB resin, 0.5-2% polyamide wax, 15-20% butyl acetate, 5-10% ethyl 3-ethoxypropionate, 0-5% weather-resistant pearlescent powder, 0-5% metallic pearlescent powder, and 5-15% nano-color paste; or

[0012] The translucent paint layer is composed of the following components in weight fractions: 40-50% saturated polyester, 2-6% butylated amino resin, 8-13% EVA wax, 1-4% CAB resin, 0.5-2% polyamide wax, 15-20% butyl acetate, 5-10% ethyl 3-ethoxypropionate, 0-5% weather-resistant pearlescent powder, 0-5% silver powder, and 5-15% weather-resistant color paste.

[0013] In one embodiment, the protective coating layer comprises the following components in weight fractions: 50-60% hydroxyl acrylic resin, 10-15% anti-sagging resin, 3-6% hydroxyl-containing hyperbranched polyester, 2-4% ethylene glycol butyl ether acetate, 2-4% diethylene glycol butyl ether acetate, 2-4% ethyl 3-ethoxypropionate, 5-8% propylene glycol methyl ether acetate, 8-12% butyl acetate, 0.8-1% light stabilizer, 0.6-0.8% UV absorber, 0.1-0.3% conductive agent, 0.001% drying agent, 0.1-0.3% polyether-modified polydimethylsiloxane, and 0.5-1% polyacrylate leveling agent; or

[0014] The protective coating layer is composed of the following components in the indicated weight percentages: 55-65% hydroxyl acrylic resin, 10-15% anti-sagging resin, 2-4% ethylene glycol butyl ether acetate, 1-3% diethylene glycol butyl ether acetate, 2-4% ethyl 3-ethoxypropionate, 5-8% propylene glycol methyl ether acetate, 8-12% butyl acetate, 0.8-1% light stabilizer, 0.6-0.8% UV absorber, 0.1-0.3% conductive agent, 0.001% drier, 0.08-0.2% polyether-modified polydimethylsiloxane, and 0.3-0.8% polyacrylate leveling agent.

[0015] In one embodiment, another transparent primer layer is provided between the laser-engraved layer and the translucent colored paint layer.

[0016] The present invention also discloses a method for processing the above-mentioned automobile bumper structure, comprising the following steps:

[0017] S1. Prepare a transparent PP bar made of PP material;

[0018] S2. Spray a layer of transparent primer onto the surface of the transparent PP bar to form a transparent primer layer. The transparent primer is composed of the following components in weight fractions: chlorinated polyolefin resin 20-30%, polyester phosphate adhesion promoter 1-2%, acrylic modified resin 1-3%, butyl acetate 25-30%, xylene 25-30%, cyclohexanone 13-18%, and modified polymer leveling agent 0.1-0.4%.

[0019] S3. Spray a layer of laser engraving primer onto the surface of the transparent primer layer to form a laser engraving layer. The laser engraving primer is composed of the following components in weight fractions: 20-35% modified acrylic polyol resin, 1-2% chlorinated polyolefin, 40-60% conductive opacifying black paste, 3-8% butyl acetate, 5-15% xylene, 3-6% cyclohexanone, and 0-0.8% laser engraving powder.

[0020] S4. Laser engraving is performed on the surface of the laser engraving layer to form a laser engraving pattern;

[0021] S5. Spray a translucent paint onto the laser-engraved layer to form a translucent paint layer. The translucent paint is composed of the following components in weight fractions: 40-50% saturated polyester, 2-6% butylated amino resin, 8-13% EVA wax, 1-4% CAB resin, 0.5-2% polyamide wax, 15-20% butyl acetate, 5-10% ethyl 3-ethoxypropionate, 0-10% pearlescent powder, and 5-15% color paste.

[0022] S6. Spray a high-leveling varnish onto the translucent colored paint layer to form a protective paint film layer. The high-leveling varnish is composed of the following components in the indicated weight percentages: 50-65% hydroxyl acrylic resin, 10-15% anti-sagging resin, 0-6% hydroxyl-containing hyperbranched polyester, 2-4% ethylene glycol butyl ether acetate, 1-4% diethylene glycol butyl ether acetate, 2-4% ethyl 3-ethoxypropionate, 5-8% propylene glycol methyl ether acetate, 8-12% butyl acetate, 0.8-1% light stabilizer, 0.6-0.8% UV absorber, 0.1-0.3% conductive agent, 0.001% drier, 0.08-0.3% polyether-modified polydimethylsiloxane, and 0.3-1% polyacrylate leveling agent.

[0023] In one embodiment, the laser engraving primer is composed of the following components in weight fractions: 20-35% modified acrylic polyol resin, 1-2% chlorinated polyolefin, 40-60% conductive opacifying black paste, 3-8% butyl acetate, 5-15% xylene, 3-6% cyclohexanone, and 0.5% laser engraving powder.

[0024] In one embodiment, after laser engraving is performed on the surface of the laser engraving layer to form a laser engraving pattern, a transparent primer is sprayed onto the surface of the laser engraving layer to form a laser engraving protective layer, wherein the translucent paint is sprayed onto the laser engraving protective layer.

[0025] The automotive bumper structure and its processing method of the present invention improve the adhesion and water resistance of the transparent primer layer on the surface of the transparent PP bumper by adding acrylic modified resin and chlorinated polyolefin resin to the transparent primer layer, along with polyester phosphate adhesion promoter and modified polymer leveling agent, thus preventing the coating from peeling off the surface of the transparent PP bumper. Furthermore, by setting a laser-engraved pattern on the laser-engraved layer, when the light strip is turned on, light passes through the transparent PP bumper and the laser-engraved pattern to display a preset pattern, giving the bumper a specific shape and thus meeting the user's needs for the bumper's appearance, which is beneficial to enhancing the product's market competitiveness. Attached Figure Description

[0026] Figure 1 This is a cross-sectional structural diagram of a car bumper structure in one embodiment of the present invention;

[0027] Figure 2 This is a flowchart of a method for processing an automobile bumper structure according to one embodiment of the present invention. Detailed Implementation

[0028] To make the above-mentioned objects, features, and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of the present invention. However, the present invention can be practiced in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0029] Please see Figure 1 This invention discloses a car bumper structure with strong coating adhesion and capable of displaying preset patterns. This bumper structure is used to install on the front and rear ends of a car body and works in conjunction with light strips on the car body surface. In this embodiment, the transparent PP bumper body 100 is made of PP material. PP (Polypropylene) is a semi-crystalline thermoplastic with high impact resistance, strong mechanical properties, and resistance to various organic solvents and acid / alkali corrosion. This ensures the mechanical strength of the car bumper structure while extending its service life. Furthermore, using PP material for the main body of the car bumper structure allows for a certain degree of light transmittance. Thus, when the light strip is turned on, the light emitted from the light strip will pass through the transparent PP bumper body 100, giving it a luminous effect. Additionally, depending on the size and processing technology limitations of the transparent PP bumper body 100, it can be transparent or semi-transparent to ensure that the light emitted from the light strip can pass through it.

[0030] In this embodiment, a transparent PP bumper body 100 is provided with a transparent primer layer 200, a laser-engraved layer 300, a translucent colored paint layer 400, and a paint film protective layer 500 stacked sequentially on its surface. The laser-engraved layer 300 has a laser-engraved pattern. Thus, when the light emitted by the light strip passes through the transparent PP bumper body 100 and sequentially passes through the transparent primer layer 200, the laser-engraved layer 300, the translucent colored paint layer 400, and the paint film protective layer 500, a pattern with the same shape as the laser-engraved pattern will be formed on the side of the paint film protective layer 500 facing away from the transparent PP bumper body 100, thereby meeting the user's aesthetic requirements for the car bumper structure. Furthermore, the transparent primer layer 200 is composed of the following components in weight percentages: 20-30% chlorinated polyolefin resin, 1-2% polyester phosphate adhesion promoter, 1-3% acrylic modified resin, 25-30% butyl acetate, 25-30% xylene, 13-18% cyclohexanone, and 0.1-0.4% modified polymer leveling agent; the laser engraving layer 300 is composed of the following components in weight percentages: 20-35% modified acrylic polyol resin, 1-2% chlorinated polyolefin, 40-60% conductive opacifying black paste, 3-8% butyl acetate, 5-15% xylene, 3-6% cyclohexanone, and 0-0.8% laser engraving powder; light transmission. The paint layer 400 is composed of the following components in weight fractions: 40-50% saturated polyester, 2-6% butylated amino resin, 8-13% EVA wax, 1-4% CAB resin, 0.5-2% polyamide wax, 15-20% butyl acetate, 5-10% ethyl 3-ethoxypropionate, 0-10% pearlescent powder, and 5-15% color paste. The paint film protective layer 500 serves two purposes: firstly, it ensures that light passing through the laser engraving layer 300 and the translucent paint layer 400 can reach the environment so that users or other personnel can observe the pattern displayed on the car bumper structure when the lights are on; secondly, the paint film protective layer 500 also protects the translucent paint layer 400 to ensure its light transmission effect. The protective coating 500 is composed of the following components by weight percentage: 50-65% hydroxyl acrylic resin, 10-15% anti-sagging resin, 0-6% hydroxyl-containing hyperbranched polyester, 2-4% ethylene glycol butyl ether acetate, 1-4% diethylene glycol butyl ether acetate, 2-4% ethyl 3-ethoxypropionate, 5-8% propylene glycol methyl ether acetate, 8-12% butyl acetate, 0.8-1% light stabilizer, 0.6-0.8% UV absorber, 0.1-0.3% conductive agent, 0.001% drier, 0.08-0.3% polyether-modified polydimethylsiloxane, and 0.3-1% polyacrylate leveling agent. In addition, another transparent primer layer 200 is provided between the laser engraving layer 300 and the translucent paint layer 400. By providing another transparent primer layer 200 between the laser engraving layer 300 and the translucent paint layer 400, the laser engraving layer 300 can be protected and the stability of the translucent paint layer 400 on the laser engraving layer 300 can be improved while ensuring that the light can pass through smoothly.

[0031] The following examples illustrate the effectiveness of this car bumper structure.

[0032] Example 1

[0033] The car bumper structure includes a transparent PP bumper body 100. The surface of the transparent PP bumper body 100 is sequentially stacked with a transparent primer layer 200, a laser engraving layer 300, a translucent colored paint layer 400, and a paint film protective layer 500. The laser engraving layer 300 has a laser engraved pattern.

[0034] The transparent primer layer 200 is composed of the following components in weight fractions: chlorinated polyolefin resin 20-30%, polyester phosphate adhesion promoter 1-2%, acrylic modified resin 1-3%, butyl acetate 25-30%, xylene 25-30%, cyclohexanone 13-18%, and modified polymer leveling agent 0.1-0.4%.

[0035] The laser engraving layer 300 is composed of the following components by weight fraction: 25-35% modified acrylic polyol resin, 1-2% chlorinated polyolefin, 40-50% conductive masking black paste, 3-8% butyl acetate, 10-15% xylene, and 3-6% cyclohexanone.

[0036] The translucent varnish layer 400 is composed of the following components by weight percentage: 40-50% saturated polyester, 2-6% butylated amino resin, 8-13% EVA wax, 1-4% CAB resin, 0.5-2% polyamide wax, 15-20% butyl acetate, 5-10% ethyl 3-ethoxypropionate, 0-5% weather-resistant pearlescent powder, 0-5% silver powder, and 5-15% weather-resistant color paste. The 40-50% saturated polyester includes 35-40% saturated polyester resin and 5-10% anti-sagging saturated polyester; the 1-4% CAB resin includes 0.5-2% CAB resin 381-2 and 0.5-2% CAB resin 381-0.1; the polyamide wax is pre-activated polyamide wax.

[0037] The protective coating 500 is composed of the following components by weight percentage: 55-65% hydroxyl acrylic resin, 10-15% anti-sagging resin, 2-4% ethylene glycol butyl ether acetate, 1-3% diethylene glycol butyl ether acetate, 2-4% ethyl 3-ethoxypropionate, 5-8% propylene glycol methyl ether acetate, 8-12% butyl acetate, 0.8-1% light stabilizer, 0.6-0.8% UV absorber, 0.1-0.3% conductive agent, 0.001% drier, 0.08-0.2% polyether-modified polydimethylsiloxane, and 0.3-0.8% polyacrylate leveling agent. The light stabilizer is Tinuvin 292, the UV absorber is Tinuvin 400, and the conductive agent is BYK-ES80.

[0038] Example 2

[0039] The car bumper structure includes a transparent PP bumper body 100. The surface of the transparent PP bumper body 100 is sequentially stacked with a transparent primer layer 200, a laser engraving layer 300, a translucent colored paint layer 400, and a paint film protective layer 500. The laser engraving layer 300 has a laser engraved pattern.

[0040] The transparent primer layer 200 is composed of the following components in weight fractions: chlorinated polyolefin resin 20-30%, polyester phosphate adhesion promoter 1-2%, acrylic modified resin 1-3%, butyl acetate 25-30%, xylene 25-30%, cyclohexanone 13-18%, and modified polymer leveling agent 0.1-0.4%.

[0041] The laser engraving layer 300 is composed of the following components by weight fraction: 20-30% modified acrylic polyol resin, 1-2% chlorinated polyolefin, 50-60% conductive masking black paste, 3-8% butyl acetate, 5-10% xylene, 3-6% cyclohexanone, and 0.3-0.8% laser engraving powder.

[0042] The translucent paint layer 400 is composed of the following components by weight percentage: 40-50% saturated polyester, 2-6% butylated amino resin, 8-13% EVA wax, 1-4% CAB resin, 0.5-2% polyamide wax, 15-20% butyl acetate, 5-10% ethyl 3-ethoxypropionate, 0-5% weather-resistant pearlescent powder, 0-5% metallic pearlescent powder, and 5-15% nano-color paste. Preferably, the nano-color paste is an ultrafine weather-resistant nano-color paste. The 40-50% saturated polyester includes 35-40% saturated polyester resin and 5-10% anti-sagging saturated polyester; the 1-4% CAB resin includes 0.5-2% CAB resin 381-2 and 0.5-2% CAB resin 381-0.1; the polyamide wax is a pre-activated polyamide wax.

[0043] The protective coating 500 is composed of the following components by weight percentage: 50-60% hydroxyl acrylic resin, 10-15% anti-sagging resin, 3-6% hydroxyl-containing hyperbranched polyester, 2-4% ethylene glycol butyl ether acetate, 2-4% diethylene glycol butyl ether acetate, 2-4% ethyl 3-ethoxypropionate, 5-8% propylene glycol methyl ether acetate, 8-12% butyl acetate, 0.8-1% light stabilizer, 0.6-0.8% UV absorber, 0.1-0.3% conductive agent, 0.001% drier, 0.1-0.3% polyether-modified polydimethylsiloxane, and 0.5-1% polyacrylate leveling agent. The light stabilizer is Tinuvin 292, the UV absorber is Tinuvin 400, and the conductive agent is BYK-ES80.

[0044] Comparative Example 1

[0045] The car bumper structure includes a transparent PP bumper body 100. The surface of the transparent PP bumper body 100 is sequentially stacked with a transparent primer layer 200, a laser engraving layer 300, a translucent colored paint layer 400, and a paint film protective layer 500. The laser engraving layer 300 has a laser engraved pattern.

[0046] The transparent primer layer 200 is composed of the following components in weight fractions: chlorinated polyolefin resin 15-20%, butyl acetate 25-30%, xylene 35-40%, cyclohexanone 13-18%, and modified polymer leveling agent 0.1-0.4%.

[0047] The laser engraving layer 300 is composed of the following components by weight fraction: 20-30% modified acrylic polyol resin, 1-2% chlorinated polyolefin, 50-60% conductive masking black paste, 3-8% butyl acetate, 5-10% xylene, 3-6% cyclohexanone, and 0.3-0.8% laser engraving powder.

[0048] The translucent paint layer 400 is composed of the following components by weight percentage: 40-50% saturated polyester, 2-6% butylated amino resin, 8-13% EVA wax, 1-4% CAB resin, 0.5-2% polyamide wax, 15-20% butyl acetate, 5-10% ethyl 3-ethoxypropionate, 0-5% weather-resistant pearlescent powder, 0-5% metallic pearlescent powder, and 5-15% nano-color paste. Preferably, the nano-color paste is an ultrafine weather-resistant nano-color paste. The 40-50% saturated polyester includes 35-40% saturated polyester resin and 5-10% anti-sagging saturated polyester; the 1-4% CAB resin includes 0.5-2% CAB resin 381-2 and 0.5-2% CAB resin 381-0.1; the polyamide wax is a pre-activated polyamide wax.

[0049] The protective coating 500 is composed of the following components by weight percentage: 50-60% hydroxyl acrylic resin, 10-15% anti-sagging resin, 3-6% hydroxyl-containing hyperbranched polyester, 2-4% ethylene glycol butyl ether acetate, 2-4% diethylene glycol butyl ether acetate, 2-4% ethyl 3-ethoxypropionate, 5-8% propylene glycol methyl ether acetate, 8-12% butyl acetate, 0.8-1% light stabilizer, 0.6-0.8% UV absorber, 0.1-0.3% conductive agent, 0.001% drier, 0.1-0.3% polyether-modified polydimethylsiloxane, and 0.5-1% polyacrylate leveling agent. The light stabilizer is Tinuvin 292, the UV absorber is Tinuvin 400, and the conductive agent is BYK-ES80.

[0050] Comparative Example 2

[0051] The car bumper structure includes a transparent PP bumper body 100. The surface of the transparent PP bumper body 100 is sequentially stacked with a transparent primer layer 200, a laser engraving layer 300, a translucent colored paint layer 400, and a paint film protective layer 500. The laser engraving layer 300 has a laser engraved pattern.

[0052] The transparent primer layer 200 is composed of the following components in weight fractions: chlorinated polyolefin resin 20-30%, butyl acetate 25-30%, xylene 25-35%, cyclohexanone 13-18%, and modified polymer leveling agent 0.1-0.4%.

[0053] The laser engraving layer 300 is composed of the following components by weight fraction: 20-30% modified acrylic polyol resin, 1-2% chlorinated polyolefin, 50-60% conductive masking black paste, 3-8% butyl acetate, 5-10% xylene, 3-6% cyclohexanone, and 0.3-0.8% laser engraving powder.

[0054] The translucent paint layer 400 is composed of the following components by weight percentage: 40-50% saturated polyester, 2-6% butylated amino resin, 8-13% EVA wax, 1-4% CAB resin, 0.5-2% polyamide wax, 15-20% butyl acetate, 5-10% ethyl 3-ethoxypropionate, 0-5% weather-resistant pearlescent powder, 0-5% metallic pearlescent powder, and 5-15% nano-color paste. Preferably, the nano-color paste is an ultrafine weather-resistant nano-color paste. The 40-50% saturated polyester includes 35-40% saturated polyester resin and 5-10% anti-sagging saturated polyester; the 1-4% CAB resin includes 0.5-2% CAB resin 381-2 and 0.5-2% CAB resin 381-0.1; the polyamide wax is a pre-activated polyamide wax.

[0055] The protective coating 500 is composed of the following components by weight percentage: 50-60% hydroxyl acrylic resin, 10-15% anti-sagging resin, 3-6% hydroxyl-containing hyperbranched polyester, 2-4% ethylene glycol butyl ether acetate, 2-4% diethylene glycol butyl ether acetate, 2-4% ethyl 3-ethoxypropionate, 5-8% propylene glycol methyl ether acetate, 8-12% butyl acetate, 0.8-1% light stabilizer, 0.6-0.8% UV absorber, 0.1-0.3% conductive agent, 0.001% drier, 0.1-0.3% polyether-modified polydimethylsiloxane, and 0.5-1% polyacrylate leveling agent. The light stabilizer is Tinuvin 292, the UV absorber is Tinuvin 400, and the conductive agent is BYK-ES80.

[0056] Experimental verification revealed that in Example 1, the adhesion of the transparent primer layer 200 was grade 0; the thickness of the masking film for laser engraving was 15μm, that is, the thickness of the laser engraving layer 300 before the laser engraving pattern was set was 15μm. Under these conditions, the laser engraving removal rate was 90~95%; the light transmittance of the translucent paint layer 400 was less than or equal to 7.5, the light transmittance was uneven, and the translucent paint layer 400 produced a cloud-like shadow when transmitting light, and the translucent paint layer 400 had a grainy texture, which would affect the light emitted through the laser engraving layer 300, and thus affect the pattern effect displayed when the car bumper structure was illuminated; the orange peel grade R of the paint film protective layer 500 was 6.5~7.

[0057] In Example 2, the adhesion of the transparent primer layer 200 is grade 0; the thickness of the masking film for laser engraving is 10 μm, that is, the thickness of the laser engraving layer 300 before the laser engraving pattern is set is 10 μm. Under this condition, the laser engraving removal rate is greater than 98%; the light transmittance of the translucent paint layer 400 is greater than or equal to 7.5, and its light transmittance is uniform and without cloudiness; the orange peel grade R of the paint film protective layer 500 is 7~8.

[0058] In Comparative Example 1, the adhesion of the transparent primer layer 200 is grade 1-2; the thickness of the masking film for laser engraving is 10μm, that is, the thickness of the laser engraving layer 300 before the laser engraving pattern is set is 10μm. Under this condition, the laser engraving removal rate is greater than 98%; the light transmittance of the translucent paint layer 400 is greater than or equal to 7.5, and its light transmittance is uniform without cloudiness; the orange peel grade R of the paint film protective layer 500 is 7~8.

[0059] In Comparative Example 2, the adhesion of the transparent primer layer 200 is grade 0-1; the thickness of the masking film for laser engraving is 10μm, that is, the thickness of the laser engraving layer 300 before the laser engraving pattern is set is 10μm. Under this condition, the laser engraving removal rate is greater than 98%; the light transmittance of the translucent paint layer 400 is greater than or equal to 7.5, and its light transmittance is uniform without cloudiness; the orange peel grade R of the paint film protective layer 500 is 7~8.

[0060] As can be seen, compared to the compositions of Comparative Examples 1 and 2, the transparent primer layer 200 of Examples 1 and 2, with the addition of polyester phosphate adhesion promoter and acrylic modified resin, improves the adhesion performance of the coating. The transparent primer layer 200 has stronger adhesion to the transparent PP bumper body 100 made of PP material, which can prevent the coating from peeling off the surface of the car bumper structure and maintain the product shape. In Example 2, by adding laser engraving powder, the effect of laser engraving patterns on the laser engraving layer 300 can be improved, avoiding the formation of burrs on the laser engraving area after laser engraving, and improving the laser removal rate. Furthermore, compared to Example 1, Example 2 uses metallic pearlescent powder instead of silver powder and nano-color paste instead of ordinary weather-resistant color paste, which can improve the light transmittance and light transmission effect of the translucent paint layer 400. After adopting the above-described translucent paint layer 400, the light transmittance of the translucent paint layer 400 is greater than or equal to 7.5%, and its light transmission is uniform and free of cloudiness. Thus, the translucent paint layer 400 achieves high opacity in the absence of light and high transmittance under light. Therefore, during the day when the LED strips are off, the color of the coating on the surface of the car bumper structure appears uniform; at night when the LED strips are on, light passes through the translucent paint in the laser-engraved areas, revealing different laser-engraved patterns, thereby improving the shape of the car bumper structure. Furthermore, the use of metallic pearlescent powder and nano-pigment can solve the defect of pigment agglomeration within the translucent paint layer 400, which causes a cloudy appearance when transmitting light. In addition, compared with Example 1, Example 2 adds hydroxyl-containing hyperbranched polyester and adjusts the proportion of polyacrylate leveling agent, which can improve the leveling performance of the raw material of the paint film protective layer 500 on the surface of the translucent paint layer 400, improve the orange peel grade of the paint film protective layer 500, and thus make the car bumper structure have a high leveling, high fullness and high hardness appearance coating.

[0061] Please combine Figure 1 and Figure 2 The present invention also discloses a method for processing the above-mentioned automobile bumper structure, the method comprising the following steps:

[0062] S1. Prepare a transparent PP bar (100mm) made of PP material.

[0063] S2. Spray a layer of transparent primer onto the surface of the transparent PP bar 100 to form a transparent primer layer 200. The transparent primer consists of the following components in weight fractions: chlorinated polyolefin resin 20-30%, polyester phosphate adhesion promoter 1-2%, acrylic modified resin 1-3%, butyl acetate 25-30%, xylene 25-30%, cyclohexanone 13-18%, and modified polymer leveling agent 0.1-0.4%.

[0064] S3. Spray a layer of laser engraving primer onto the surface of the transparent primer layer 200 to form the laser engraving layer 300. The laser engraving primer is composed of the following components in weight percentages: 20-35% modified acrylic polyol resin, 1-2% chlorinated polyolefin, 40-60% conductive opacifying black paste, 3-8% butyl acetate, 5-15% xylene, 3-6% cyclohexanone, and 0-0.8% laser engraving powder. Preferably, the laser engraving primer is composed of the following components in weight percentages: 20-30% modified acrylic polyol resin, 1-2% chlorinated polyolefin, 50-60% conductive opacifying black paste, 3-8% butyl acetate, 5-10% xylene, 3-6% cyclohexanone, and 0.3-0.8% laser engraving powder. In a further preferred embodiment, the laser engraving primer comprises the following components in weight fractions: 20-35% modified acrylic polyol resin, 1-2% chlorinated polyolefin, 40-60% conductive opacifying black paste, 3-8% butyl acetate, 5-15% xylene, 3-6% cyclohexanone, and 0.5% laser engraving powder. By adding laser engraving powder to the laser engraving layer 300, the effect of laser engraving patterns on the laser engraving layer 300 can be improved, burrs can be avoided on the laser engraving layer 300 after laser engraving operations, and the laser removal rate of laser engraving operations can be improved.

[0065] S4. Laser engraving is performed on the surface of laser engraving layer 300 to form a laser engraving pattern.

[0066] S5. Spray a translucent paint onto the laser-engraved layer 300 to form a translucent paint layer 400. The translucent paint consists of the following components by weight percentage: 40-50% saturated polyester, 2-6% butylated amino resin, 8-13% EVA wax, 1-4% CAB resin, 0.5-2% polyamide wax, 15-20% butyl acetate, 5-10% ethyl 3-ethoxypropionate, 0-10% pearlescent powder, and 5-15% color paste. It should be noted that after spraying the translucent paint onto the surface of the laser-engraved layer 300, the contour of the side of the translucent paint layer 400 that contacts the laser-engraved layer 300 conforms to the contour of the surface of the laser-engraved layer 300. This fills the recessed and raised areas of the laser-engraved pattern, facilitating light refraction at the interface between the laser-engraved pattern and the translucent paint, thus displaying the pattern. Further preferably, the translucent paint is composed of the following components in the indicated weight percentages: 40-50% saturated polyester, 2-6% butylated amino resin, 8-13% EVA wax, 1-4% CAB resin, 0.5-2% polyamide wax, 15-20% butyl acetate, 5-10% ethyl 3-ethoxypropionate, 0-5% weather-resistant pearlescent powder, 0-5% metallic pearlescent powder, and 5-15% nano-pigment. The use of weather-resistant pearlescent powder and metallic pearlescent powder, along with nano-pigment, improves the light transmittance and light transmission effect of the translucent paint layer 400, resulting in a light transmittance greater than or equal to 7.5%. The light transmission is uniform and free of cloudiness. This allows the translucent paint layer 400 to have high opacity in the absence of light and high transmittance under light, thus improving the shape of the car bumper structure under different lighting conditions.

[0067] S6. Spray a high-leveling clear varnish onto the translucent colored paint layer 400 to form a protective paint film layer 500. The high-leveling clear varnish is composed of the following components in the indicated weight percentages: 50-65% hydroxyl acrylic resin, 10-15% anti-sagging resin, 0-6% hydroxyl-containing hyperbranched polyester, 2-4% ethylene glycol butyl ether acetate, 1-4% diethylene glycol butyl ether acetate, 2-4% ethyl 3-ethoxypropionate, 5-8% propylene glycol methyl ether acetate, 8-12% butyl acetate, 0.8-1% light stabilizer, 0.6-0.8% UV absorber, 0.1-0.3% conductive agent, 0.001% drier, 0.08-0.3% polyether-modified polydimethylsiloxane, and 0.3-1% polyacrylate leveling agent. Further preferably, the high-leveling varnish is composed of the following components in the indicated weight fractions: 50-60% hydroxyl acrylic resin, 10-15% anti-sagging resin, 3-6% hydroxyl-containing hyperbranched polyester, 2-4% ethylene glycol butyl ether acetate, 2-4% diethylene glycol butyl ether acetate, 2-4% ethyl 3-ethoxypropionate, 5-8% propylene glycol methyl ether acetate, 8-12% butyl acetate, 0.8-1% light stabilizer, 0.6-0.8% UV absorber, 0.1-0.3% conductive agent, 0.001% drier, 0.1-0.3% polyether-modified polydimethylsiloxane, and 0.5-1% polyacrylate leveling agent. By adding hydroxyl-containing hyperbranched polyester to high-level clear varnish and adjusting the proportion of polyacrylate leveling agent, the leveling performance of the raw material of the paint film protective layer 500 on the surface of the translucent paint layer 400 can be improved, thereby increasing the orange peel grade of the paint film protective layer 500 and giving the car bumper structure a high-level, high-fullness, and high-hardness appearance coating.

[0068] In one embodiment, after laser engraving is performed on the surface of the laser engraving layer 300 to form a laser engraved pattern, a transparent primer is sprayed onto the surface of the laser engraving layer 300 to form a laser engraving protective layer, and a translucent colored paint is sprayed onto the laser engraving protective layer. That is, another transparent primer layer 200 is provided between the laser engraving layer 300 and the translucent colored paint layer 400. By providing another transparent primer layer 200 between the laser engraving layer 300 and the translucent colored paint layer 400, while ensuring that light can pass through smoothly, the laser engraving layer 300 can be protected and the adhesion stability of the translucent colored paint layer 400 on the laser engraving layer 300 can be improved.

[0069] The aforementioned car bumper structure and its processing method, by setting a transparent primer layer 200 on the surface of the transparent PP bumper body 100, the transparent primer layer 200 contains acrylic modified resin and chlorinated polyolefin resin, along with a polyester phosphate adhesion promoter and a modified polymer leveling agent, which improves the adhesion and water resistance of the transparent primer layer 200 on the PP material surface, thus preventing the coating from peeling off the surface of the transparent PP bumper body 100; by setting a laser engraving pattern on the laser engraving layer 300, when the light strip is turned on, the light passes through the transparent PP bumper body and the laser engraving pattern, which can display the preset pattern, giving the bumper a specific shape, thereby meeting the user's needs for the bumper's shape and helping to enhance the product's market competitiveness.

[0070] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0071] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this invention patent should be determined by the appended claims.

Claims

1. A car bumper structure for installation at the front and rear ends of a vehicle body and for use with light strips on the surface of the vehicle body, the car bumper structure comprising a transparent PP bumper body, wherein a transparent primer layer, a laser engraving layer, a light-transmitting colored paint layer and a paint film protective layer are sequentially stacked on the surface of the transparent PP bumper body, and the laser engraving layer has a laser engraving pattern. The transparent primer layer is composed of the following components by weight fraction: Chlorinated polyolefin resin 20-30%, polyester phosphate ester adhesion promoter 1-2%, acrylic modified resin 1-3%, butyl acetate 25-30%, xylene 25-30%, cyclohexanone 13-18%, modified polymer leveling agent 0.1-0.4%; The laser engraving layer is composed of the following components by weight percentage: 20-35% modified acrylic polyol resin, 1-2% chlorinated polyolefin, 40-60% conductive masking black paste, 3-8% butyl acetate, 5-15% xylene, 3-6% cyclohexanone, and 0-0.8% laser engraving powder; The translucent paint layer is composed of the following components by weight percentage: 40-50% saturated polyester, 2-6% butylated amino resin, 8-13% EVA wax, 1-4% CAB resin, 0.5-2% polyamide wax, 15-20% butyl acetate, 5-10% ethyl 3-ethoxypropionate, 0-10% pearlescent powder, and 5-15% color paste; The protective coating layer is composed of the following components in the indicated weight percentages: 50-65% hydroxyl acrylic resin, 10-15% anti-sagging resin, 0-6% hydroxyl-containing hyperbranched polyester, 2-4% ethylene glycol butyl ether acetate, 1-4% diethylene glycol butyl ether acetate, 2-4% ethyl 3-ethoxypropionate, 5-8% propylene glycol methyl ether acetate, 8-12% butyl acetate, 0.8-1% light stabilizer, 0.6-0.8% UV absorber, 0.1-0.3% conductive agent, 0.001% drier, 0.08-0.3% polyether-modified polydimethylsiloxane, and 0.3-1% polyacrylate leveling agent.

2. The automobile bumper structure according to claim 1, characterized in that, The laser-engraved layer is composed of the following components in the indicated weight percentages: 20-30% modified acrylic polyol resin, 1-2% chlorinated polyolefin, 50-60% conductive masking black paste, 3-8% butyl acetate, 5-10% xylene, 3-6% cyclohexanone, and 0.3-0.8% laser-engraved powder; or The laser-engraved layer is composed of the following components by weight fraction: 25-35% modified acrylic polyol resin, 1-2% chlorinated polyolefin, 40-50% conductive masking black paste, 3-8% butyl acetate, 10-15% xylene, and 3-6% cyclohexanone.

3. The automobile bumper structure according to claim 1, characterized in that, The translucent paint layer is composed of the following components by weight percentage: 40-50% saturated polyester, 2-6% butylated amino resin, 8-13% EVA wax, 1-4% CAB resin, 0.5-2% polyamide wax, 15-20% butyl acetate, 5-10% ethyl 3-ethoxypropionate, 0-5% weather-resistant pearlescent powder, 0-5% metallic pearlescent powder, and 5-15% nano-color paste; or The translucent paint layer is composed of the following components in weight fractions: 40-50% saturated polyester, 2-6% butylated amino resin, 8-13% EVA wax, 1-4% CAB resin, 0.5-2% polyamide wax, 15-20% butyl acetate, 5-10% ethyl 3-ethoxypropionate, 0-5% weather-resistant pearlescent powder, 0-5% silver powder, and 5-15% weather-resistant color paste.

4. The automobile bumper structure according to claim 1, characterized in that, The protective coating layer comprises the following components in the indicated weight percentages: 50-60% hydroxyl acrylic resin, 10-15% anti-sagging resin, 3-6% hydroxyl-containing hyperbranched polyester, 2-4% ethylene glycol butyl ether acetate, 2-4% diethylene glycol butyl ether acetate, 2-4% ethyl 3-ethoxypropionate, 5-8% propylene glycol methyl ether acetate, 8-12% butyl acetate, 0.8-1% light stabilizer, 0.6-0.8% UV absorber, 0.1-0.3% conductive agent, 0.001% drying agent, 0.1-0.3% polyether-modified polydimethylsiloxane, and 0.5-1% polyacrylate leveling agent; or The protective coating layer is composed of the following components in the indicated weight percentages: 55-65% hydroxyl acrylic resin, 10-15% anti-sagging resin, 2-4% ethylene glycol butyl ether acetate, 1-3% diethylene glycol butyl ether acetate, 2-4% ethyl 3-ethoxypropionate, 5-8% propylene glycol methyl ether acetate, 8-12% butyl acetate, 0.8-1% light stabilizer, 0.6-0.8% UV absorber, 0.1-0.3% conductive agent, 0.001% drier, 0.08-0.2% polyether-modified polydimethylsiloxane, and 0.3-0.8% polyacrylate leveling agent.

5. The automobile bumper structure according to claim 1, characterized in that, Another transparent primer layer is provided between the laser-engraved layer and the translucent colored paint layer.

6. A method for processing the automobile bumper structure according to any one of claims 1-5, characterized in that, Includes the following steps: S1. Prepare a transparent PP bar made of PP material; S2. Spray a layer of transparent primer onto the surface of the transparent PP bar to form a transparent primer layer. The transparent primer is composed of the following components in weight fractions: chlorinated polyolefin resin 20-30%, polyester phosphate adhesion promoter 1-2%, acrylic modified resin 1-3%, butyl acetate 25-30%, xylene 25-30%, cyclohexanone 13-18%, and modified polymer leveling agent 0.1-0.4%. S3. Spray a layer of laser engraving primer onto the surface of the transparent primer layer to form a laser engraving layer. The laser engraving primer is composed of the following components in weight fractions: 20-35% modified acrylic polyol resin, 1-2% chlorinated polyolefin, 40-60% conductive opacifying black paste, 3-8% butyl acetate, 5-15% xylene, 3-6% cyclohexanone, and 0-0.8% laser engraving powder. S4. Laser engraving is performed on the surface of the laser engraving layer to form a laser engraving pattern; S5. Spray a translucent paint onto the laser-engraved layer to form a translucent paint layer. The translucent paint is composed of the following components in weight fractions: 40-50% saturated polyester, 2-6% butylated amino resin, 8-13% EVA wax, 1-4% CAB resin, 0.5-2% polyamide wax, 15-20% butyl acetate, 5-10% ethyl 3-ethoxypropionate, 0-10% pearlescent powder, and 5-15% color paste. S6. Spray a high-leveling varnish onto the translucent colored paint layer to form a protective paint film layer. The high-leveling varnish is composed of the following components in the indicated weight percentages: 50-65% hydroxyl acrylic resin, 10-15% anti-sagging resin, 0-6% hydroxyl-containing hyperbranched polyester, 2-4% ethylene glycol butyl ether acetate, 1-4% diethylene glycol butyl ether acetate, 2-4% ethyl 3-ethoxypropionate, 5-8% propylene glycol methyl ether acetate, 8-12% butyl acetate, 0.8-1% light stabilizer, 0.6-0.8% UV absorber, 0.1-0.3% conductive agent, 0.001% drier, 0.08-0.3% polyether-modified polydimethylsiloxane, and 0.3-1% polyacrylate leveling agent.

7. The method according to claim 6, characterized in that, The laser engraving primer is composed of the following components in weight percentages: 20-35% modified acrylic polyol resin, 1-2% chlorinated polyolefin, 40-60% conductive opacifying black paste, 3-8% butyl acetate, 5-15% xylene, 3-6% cyclohexanone, and 0.5% laser engraving powder.

8. The method according to claim 6, characterized in that, After laser engraving is performed on the surface of the laser engraving layer to form a laser engraving pattern, the process also includes spraying a transparent primer onto the surface of the laser engraving layer to form a laser engraving protective layer, wherein the translucent colored paint is sprayed onto the laser engraving protective layer.

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