Automobile decoration strip with film pasting instead of paint spraying and production method of automobile decoration strip

Abstract

The invention discloses an automobile decoration strip with a film instead of paint spraying and a production method of the automobile decoration strip. The automobile decoration strip comprises a metal strip and a curing color developing film attached to the outer surface of the metal strip, the curing color developing film is composed of a PET layer, a PUR layer and a release layer, and the PUR layer is formed by UV curing resin, three reactive diluents, two photoinitiators, filler, an antioxidant and pigment black in a specific proportion through UV curing. Meanwhile, the invention discloses matched production equipment and a production method comprising the steps of curing and developing film preparation, metal strip gluing and film pasting, cooling and sizing. A traditional paint spraying process is replaced with film pasting, VOCs emission is avoided, and the environment friendliness is excellent; the cured color developing film is excellent in comprehensive performance, strong in adhesive force with a metal strip, weather-resistant and anti-aging; production equipment is high in automation degree, continuous operation is achieved, the production efficiency and the product percent of pass are greatly improved, the service life of the decoration strip is prolonged, a traditional paint spraying process can be effectively replaced, and the production equipment has important market value.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of new materials, in particular to a car trim strip with film instead of paint and a production method thereof. BACKGROUND

[0002] As an important part of the appearance of a car, the car trim strip not only plays a decorative role, but also protects the local structure of the car body. The surface coloring process of traditional car trim strips mostly adopts the paint spraying method. This process has many defects: firstly, a large amount of volatile organic compounds (VOCs) are produced in the paint spraying process, which seriously pollutes the environment and harms the health of the operators; secondly, the paint spraying process is complicated and needs to go through multiple steps such as substrate pretreatment, primer spraying, topcoat spraying, and drying and curing, which results in a long production cycle and low production efficiency; thirdly, the adhesion of the paint film formed by paint spraying to the metal substrate is limited, and problems such as peeling, cracking, and scratching are likely to occur during long-term use, especially in outdoor use environment of the car, the paint film is easy to age and discolor after high temperature and ultraviolet radiation, which affects the appearance quality and service life of the trim strip.

[0003] To solve the above-mentioned drawbacks of the paint spraying process, the industry has gradually explored the use of film instead of paint. However, the existing film materials for car trim strips have many performance defects, such as insufficient adhesion of the film layer to the metal substrate, poor weather resistance, low mechanical strength and easy breakage, insufficient surface hardness and easy scratching, and the formula system of the film material is unreasonable, the curing efficiency is low, which is difficult to meet the large-scale production needs of car trim strips. In addition, the existing film production equipment has low automation degree, unstable film material conveying tension, and problems such as bubbles and wrinkles are likely to occur during the film sticking process, resulting in low product qualification rate.

[0004] Therefore, it is of great practical significance and market value to develop a film material with reasonable formula and excellent performance, as well as a high-efficiency and stable production equipment and production method, to realize the production of car trim strips by film instead of paint. SUMMARY

[0005] Therefore, the purpose of the present application is to provide a car trim strip with film instead of paint and a production method thereof, to solve the problems of pollution, low efficiency, poor paint film performance in the paint spraying process of car trim strips in the prior art, and defects in the existing film materials and production technology.

[0006] To achieve the above-mentioned purpose, the present application provides the following technical solutions:

[0007] A car trim strip with film instead of paint;

[0008] The car trim strip comprises a metal strip and a cured color-developing film attached to the outer surface of the metal strip; the cured color-developing film comprises a PET layer, a PUR layer, and a release layer.

[0009] The raw material components of the PUR layer include, in terms of weight percentage (wt.%): one UV-curable resin, three active diluents, two photoinitiators, fillers, antioxidants, and pigment black; the raw material components are cured and formed by UV irradiation, wherein the UV-curable resin is the film-forming main body, the active diluent adjusts the system viscosity and participates in the crosslinking reaction, the photoinitiator triggers the UV curing process, the fillers improve the mechanical properties of the film layer, the antioxidants inhibit the oxidative aging of the film layer, and the pigment black gives the film layer a uniform black appearance.

[0010] Further, the one UV-curable resin is polyurethane acrylate (PUA), and its content is 76.0-78.0% in terms of weight percentage; the polyurethane acrylate is prepared by addition reaction of isocyanate, polyol, and blocking agent, and forms the main support skeleton of the developed film after curing, ensuring the adhesion and weather resistance of the film layer to the injection molding strip.

[0011] Further, among the three active diluents:

[0012] The first active diluent is 4-tert-butylcyclohexyl acrylate (TBCHA), and its content is 5.0-7.0% in terms of weight percentage, mainly used to reduce the viscosity of the UV-curable resin system, while improving the flexibility of the cured film layer to avoid cracking of the film layer due to deformation of the injection molding strip;

[0013] The second active diluent is pentaerythritol triacrylate (PETA), and its content is 10.0-11.0% in terms of weight percentage; the PETA is a multi-functional active diluent that can crosslink with the UV-curable resin to form a high-density network structure, enhancing the hardness and scratch resistance of the cured developed film;

[0014] The third active diluent is octadecyl acrylate, and its content is 3.0-4.0% in terms of weight percentage; the octadecyl acrylate can improve the compatibility of each raw material component, while adjusting the surface tension of the cured developed film, improving the flatness of the film layer during lamination.

[0015] Further, among the two photoinitiators, the first is methyl benzoylformate (MBF), and its content is 1.0-2.0% in terms of weight percentage; the MBF has high initiation activity in the 250-350 nm UV waveband, can quickly start the curing reaction, and shorten the curing period; the second is diphenyl (2,4,6-trimethylbenzoyl) phosphine oxide (TPO), and its content is 0.4-0.6% in terms of weight percentage; the TPO is suitable for the curing of thicker film layers, can solve the problem of incomplete curing of the deep layer of the film layer, and ensure the uniformity of the overall performance of the film layer.

[0016] Furthermore, the filler is silica, preferably fumed silica, with a content of 2.0-3.0% by weight and a particle size of 10-50 nm; the silica can be uniformly dispersed in the film layer, significantly improving the tensile strength and wear resistance of the cured color development film.

[0017] Furthermore, the antioxidant is 2,6-di-tert-butyl-4-methylphenol (BHT), with a content of 0.05-0.10% by weight. The BHT can inhibit the oxidative degradation of the cured color development film during long-term use, especially resisting the aging caused by high temperature and ultraviolet radiation during outdoor use in automobiles, and maintaining the stability of the film's appearance and performance.

[0018] Furthermore, the pigment black is carbon black, with a content of 0.8-1.5% by weight; the carbon black has an oil absorption value of 100-150mL / 100g and a pH value of 6.0-8.0, which can be uniformly dispersed in the film layer, ensuring a consistent black appearance and avoiding film performance defects caused by carbon black agglomeration.

[0019] Production equipment for automotive trim that uses film instead of paint;

[0020] This includes the equipment frame, equipment table, product conveyor belt, cooling air pipe, glue coating mold, glue extruder, release film layering mechanism, drive mechanism, buffer mechanism, release film winding mechanism, film roll, equipment back plate, and film application mold;

[0021] The equipment platform is installed on the top of the equipment frame, and the equipment back plate is installed on the top of the equipment platform. The film roll, buffer mechanism, drive mechanism, and release film layering mechanism are sequentially installed on the front of the equipment back plate along the film conveying direction. The release film winding mechanism is installed below the release film layering mechanism. The product conveyor belt is installed on the top of the equipment platform. The glue coating mold is installed on one side of the top of the equipment frame and connected to the output end of the extruder. The film application mold is installed at the discharge end of the glue coating mold and faces the feed end of the product conveyor belt. The cooling air pipe is installed above the feed end of the product conveyor belt.

[0022] The production method for automotive trim strips that use film instead of painting includes the following steps:

[0023] S1: Preparation of Cured Color Development Film: Weigh out the UV curing resin, 3 kinds of reactive diluents, 2 kinds of photoinitiators, filler, antioxidant and pigment black according to the weight percentage, mix and stir evenly to form a film material, coat the film material onto the surface of the PET layer, and attach the release layer under the film material layer during coating, and then expose it to a UV light source (wavelength 200-400nm, irradiation intensity 80-120mW / cm). 2 The film is cured by irradiation for 30-120 seconds. After curing, the colored film is cut into strips and then wound onto a film roll.

[0024] S2: Metal strip coating: Add hot melt adhesive to the extruder and start the extruder. The metal strip passes horizontally through the coating die, and the hot melt adhesive is evenly coated on the surface of the metal strip.

[0025] S3: Start the drive mechanism to unwind the film roll. The color developing film passes through the buffer mechanism to adjust the tension and the release film layering mechanism to remove the release film before being conveyed into the bonding mold. The color developing film is bonded to the surface of the metal strip with hot melt adhesive. It is cooled and shaped by the cold air blown out by the cooling pipe. The decorative strip is conveyed out by the conveyor belt to complete the production of the decorative strip.

[0026] Compared with the prior art, the beneficial effects of the present invention are:

[0027] 1. Excellent environmental performance: This invention uses film to replace the traditional spray painting process, and there are no VOCs emissions during the production process, which fundamentally solves the environmental pollution problem of the spray painting process and conforms to the development trend of green production; at the same time, it avoids the harm to the health of operators during the spray painting process and improves the production and working environment.

[0028] 2. Excellent Film Performance: This invention optimizes the PUR layer formulation of the cured color-developing film, using specific types and proportions of UV-curable resin, reactive diluent, photoinitiator, and other components to achieve excellent comprehensive performance of the cured film. Specifically, PUA resin, as the main film-forming agent, ensures strong adhesion and excellent weather resistance between the film and the metal strip; the three reactive diluents work synergistically to reduce system viscosity for easier application and improve the film's flexibility, hardness, and surface smoothness; the two photoinitiators used in combination achieve rapid curing and ensure complete deep curing of the film; fumed silica filler significantly improves the film's tensile strength and wear resistance; BHT antioxidant effectively inhibits oxidative aging of the film; and carbon black with specific properties ensures a uniform black appearance of the film.

[0029] 3. High production efficiency: The production method of this invention has a simple process. The curing color development film can be quickly cured by UV, and the curing cycle is only 30-120 seconds. The supporting production equipment realizes the automated continuous operation of processes such as film material transportation, tension adjustment, release film peeling, glue application, film application, and cooling and shaping. It eliminates the need for multiple drying steps in the traditional spray painting process, greatly shortens the production cycle, improves production efficiency, and is suitable for large-scale production.

[0030] 4. High product qualification rate: The production equipment of this invention is equipped with a buffer mechanism to adjust the tension of the film material, avoiding wrinkles caused by unstable tension during film material transportation; the structural design of the film-applying mold ensures precise bonding between the color developing film and the metal strip, and combined with the rapid cooling and shaping by the cooling air pipe, effectively avoids defects such as bubbles and peeling during the film-applying process, thus improving the product qualification rate.

[0031] 5. Long service life: The cured color-developing film of this invention has excellent weather resistance, anti-aging properties and mechanical properties. During long-term outdoor use in automobiles, it can effectively resist the erosion of environmental factors such as high temperature, ultraviolet rays and rain, and is not prone to aging, discoloration, cracking, scratches and other problems, thus extending the service life of automotive trim strips.

[0032] The above description is merely an overview of the technical solution of this application. In order to better understand the technical means of this application and to implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of this application more apparent and understandable, the preferred embodiments of this application are described in detail below with reference to the accompanying drawings.

[0033] The above and other objects, advantages and features of this application will become more apparent to those skilled in the art from the following detailed description of specific embodiments in conjunction with the accompanying drawings. Attached Figure Description

[0034] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, they can also be used to obtain other drawings based on these drawings without creative effort. In all drawings, similar elements or parts are generally identified by similar reference numerals. In the drawings, the elements or parts are not necessarily drawn to actual scale.

[0035] Fig. 1 This is a formula diagram of the PUR layer in the coloring film of the present invention;

[0036] Fig. 2 This is a schematic diagram of the automotive trim strip in this invention;

[0037] Fig. 3 This is a diagram of the production equipment used in this invention.

[0038] In the diagram: 1. Equipment frame; 2. Equipment platform; 3. Product conveyor belt; 4. Cooling air pipe; 5. Glue application mold; 6. Glue extruder; 7. Release film tearing mechanism; 8. Drive mechanism; 9. Buffer mechanism; 10. Release film winding mechanism; 11. Film roll; 12. Equipment back plate; 13. Film application mold. Detailed Implementation

[0039] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. In the following description, specific details such as specific configurations and components are provided merely to help fully understand the embodiments of this application. Therefore, those skilled in the art should understand that various changes and modifications can be made to the embodiments described herein without departing from the scope and spirit of this application. In addition, for clarity and brevity, descriptions of known functions and structures are omitted in the embodiments.

[0040] Furthermore, this application is used to repeat reference numerals and / or letters in different examples. Such repetition is for simplification and clarity purposes and does not in itself indicate a relationship between the various embodiments and / or settings discussed.

[0041] In this article, the term "and / or" is merely a description of the relationship between related objects, indicating that there are three possible relationships, such as A and / or B, which means: A exists alone, B exists alone, and A and B exist simultaneously. The term " / and" describes another type of relationship between related objects, indicating that there are two possible relationships, such as A / and B, which means: A exists alone, and A and B exist alone. In addition, the character " / " in this article generally indicates that the related objects before and after it are in an "or" relationship.

[0042] It should also be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion.

[0043] Please see Figs. 1-3 This invention provides a technical solution for automotive trim strips that use a film instead of paint, and a method for producing the same.

[0044] Example 1

[0045] A type of automotive trim that uses a film instead of paint includes a metal strip and a cured color-developing film adhered to the outer surface of the metal strip. The cured color-developing film includes a PET layer, a PUR layer, and a release layer.

[0046] The raw material components of the PUR layer, by weight percentage, are: polyurethane acrylate (PUA) 77.0%, 4-tert-butylcyclohexyl acrylate (TBCHA) 6.0%, pentaerythritol triacrylate (PETA) 10.5%, octadecyl acrylate 3.5%, methyl benzoylformate (MBF) 1.5%, diphenyl (2,4,6-trimethylbenzoyl)phosphine oxide (TPO) 0.5%, fumed silica (particle size 30nm) 2.5%, 2,6-di-tert-butyl-4-methylphenol (BHT) 0.08%, and carbon black (oil absorption value 120mL / 100g, pH value 7.0) 1.2%.

[0047] The aforementioned automotive trim strips are manufactured using the following production equipment and methods:

[0048] The production equipment includes a machine frame (1), a machine table (2), a product conveyor belt (3), a cooling air pipe (4), a glue coating mold (5), a glue extruder (6), a release film layering mechanism (7), a drive mechanism (8), a buffer mechanism (9), a release film winding mechanism (10), a film roll (11), a machine back plate (12), and a film application mold (13); the installation method of each component is as described in the technical solution.

[0049] The production method includes the following steps:

[0050] S1: Preparation of Cured Color Development Film: Weigh each raw material component according to the above weight percentages, put them into a mixing device and mix for 30 minutes until uniform to form a film material; coat the film material onto the surface of the PET layer using a coating device, with a coating thickness of 0.1 mm, and attach a release layer under the film material layer during coating; then place the coated composite layer in a UV curing device, using a wavelength of 300 nm and an irradiation intensity of 100 mW / cm². 2 Irradiate with a UV light source for 60 seconds to cure into a film; cut the cured color development film into strips that match the width of the metal strip using a strip cutting device, and then roll it up on a film roll (11).

[0051] S2: Metal strip coating: Put hot melt adhesive (model: EVA hot melt adhesive, melting point 120℃) into the extruder (6), start the extruder (6), set the extrusion temperature to 130℃, the metal strip (material: aluminum alloy) passes through the coating mold (5) laterally, and the hot melt adhesive is uniformly coated on the outer surface of the metal strip with a thickness of 0.05mm.

[0052] S3: Film application and shaping: Start the drive mechanism (8) to unwind the film roll (11). The color developing film passes through the buffer mechanism (9) to adjust the tension (tension value is set to 5N) and the release film layering mechanism (7) to remove the release film. Then it is fed into the bonding mold (13). At the same time, the metal strip after applying glue is fed to the bonding mold (13). The color developing film is precisely bonded to the surface of the metal strip through hot melt adhesive. Start the cooling air pipe (4) to blow out cold air at a temperature of 25℃ to cool and shape the bonded trim strip. The cooling time is 30s. The shaped trim strip is conveyed out through the product conveyor belt (3) to complete the trim strip production.

[0053] The performance of the automotive trim prepared in this embodiment was tested, and the results are as follows: the adhesion between the film and the metal strip (cross-cut adhesion test) was grade 0; the hardness of the film (pencil hardness test) was 3H; the weather resistance (xenon lamp aging test, 1000h) showed no discoloration, cracking, or peeling of the film; the wear resistance (Taber wear test, 500 revolutions) showed wear amount ≤0.01g; and the flexibility (bending test, bending radius 10mm) showed no cracking of the film.

[0054] Example 2

[0055] A type of automotive trim that uses a film instead of paint includes a metal strip and a cured color-developing film adhered to the outer surface of the metal strip. The cured color-developing film includes a PET layer, a PUR layer, and a release layer.

[0056] The raw material components of the PUR layer, by weight percentage, are: polyurethane acrylate (PUA) 76.0%, 4-tert-butylcyclohexyl acrylate (TBCHA) 7.0%, pentaerythritol triacrylate (PETA) 10.0%, octadecyl acrylate 4.0%, methyl benzoylformate (MBF) 1.0%, diphenyl (2,4,6-trimethylbenzoyl)phosphine oxide (TPO) 0.6%, fumed silica (particle size 10nm) 3.0%, 2,6-di-tert-butyl-4-methylphenol (BHT) 0.10%, and carbon black (oil absorption value 100mL / 100g, pH value 6.0) 1.5%.

[0057] The production equipment is the same as in Example 1. The UV curing parameters for S1 in the production method are: wavelength 200nm, irradiation intensity 80mW / cm². 2 The irradiation time was 120s; the extrusion temperature of S2 was 125℃, and the coating thickness was 0.04mm; the tension value of S3 was set to 4N, the cooling temperature was 20℃, and the cooling time was 40s. The remaining steps were the same as in Example 1.

[0058] The performance of the automotive trim prepared in this embodiment was tested, and the results are as follows: the adhesion between the film and the metal strip (cross-cut adhesion test) was grade 0; the hardness of the film (pencil hardness test) was 2H; the weather resistance (xenon lamp aging test, 1000h) showed no discoloration, cracking, or peeling of the film; the wear resistance (Taber wear test, 500 revolutions) showed wear amount ≤0.015g; and the flexibility (bending test, bending radius 10mm) showed no cracking of the film.

[0059] Example 3

[0060] A type of automotive trim that uses a film instead of paint includes a metal strip and a cured color-developing film adhered to the outer surface of the metal strip. The cured color-developing film includes a PET layer, a PUR layer, and a release layer.

[0061] The raw material components of the PUR layer, by weight percentage, are: polyurethane acrylate (PUA) 78.0%, 4-tert-butylcyclohexyl acrylate (TBCHA) 5.0%, pentaerythritol triacrylate (PETA) 11.0%, octadecyl acrylate 3.0%, methyl benzoylformate (MBF) 2.0%, diphenyl (2,4,6-trimethylbenzoyl)phosphine oxide (TPO) 0.4%, fumed silica (particle size 50nm) 2.0%, 2,6-di-tert-butyl-4-methylphenol (BHT) 0.05%, and carbon black (oil absorption value 150mL / 100g, pH value 8.0) 0.8%.

[0062] The production equipment is the same as in Example 1. The UV curing parameters for S1 in the production method are: wavelength 400nm, irradiation intensity 120mW / cm². 2 The irradiation time is 30s; the extrusion temperature of S2 is 135℃, and the coating thickness is 0.06mm; the tension value of S3 is set to 6N, the cooling temperature is 30℃, and the cooling time is 20s. The remaining steps are the same as in Example 1.

[0063] The performance of the automotive trim prepared in this embodiment was tested, and the results are as follows: the adhesion between the film and the metal strip (cross-cut adhesion test) was grade 0; the hardness of the film (pencil hardness test) was 4H; the weather resistance (xenon lamp aging test, 1000h) showed no discoloration, cracking, or peeling of the film; the wear resistance (Taber wear test, 500 revolutions) showed wear amount ≤0.008g; and the flexibility (bending test, bending radius 10mm) showed no cracking of the film.

[0064] The above description is merely a preferred embodiment of the present invention and does not limit the scope of protection of the present invention. For those skilled in the art, the present invention can be modified and varied in many ways. Any changes, modifications, substitutions, integrations, and parameter alterations to these embodiments within the spirit and principles of the present invention, achieved through conventional substitutions or by achieving the same function without departing from the principles and spirit of the present invention, fall within the scope of protection of the present invention.

Claims

1. A type of automotive trim strip that uses a film instead of paint, characterized in that, It includes a metal strip and a cured color-developing film adhered to the outer surface of the metal strip; the cured color-developing film includes a PET layer, a PUR layer and a release layer; The PUR layer, by weight percentage (wt.%), comprises: one UV-curable resin, three reactive diluents, two photoinitiators, fillers, antioxidants, and pigment black. The raw material components are cured and shaped by UV irradiation, wherein the UV-curable resin is the main film-forming agent, the reactive diluent adjusts the viscosity of the system and participates in the crosslinking reaction, the photoinitiator triggers the UV curing process, the filler improves the mechanical properties of the film layer, the antioxidant inhibits the oxidative aging of the film layer, and the pigment black gives the film layer a uniform black appearance.

2. The cured color-developing film according to claim 1, characterized in that, The UV-curable resin is polyurethane acrylate (PUA), with a content of 76.0-78.0% by weight. The polyurethane acrylate is prepared by an addition reaction of isocyanate, polyol and end-capping agent. After curing, it forms the main supporting skeleton of the color-developing film, ensuring the adhesion and weather resistance of the film layer to the injection molding strip.

3. The cured color-developing film according to claim 1, characterized in that, Of the three reactive diluents: The first reactive diluent is 4-tert-butylcyclohexyl acrylate (TBCHA), with a content of 5.0-7.0% by weight. It is mainly used to reduce the viscosity of the UV-curable resin system and improve the flexibility of the cured film to prevent the film from cracking due to the deformation of the injection molding strip. The second type of reactive diluent is pentaerythritol triacrylate (PETA), with a content of 10.0-11.0% by weight. PETA is a multifunctional reactive diluent that can crosslink with UV-curable resin to form a high-density network structure, thereby enhancing the hardness and scratch resistance of the cured color development film. The third reactive diluent is octadecyl acrylate, with a content of 3.0-4.0% by weight. The octadecyl acrylate can improve the compatibility of each raw material component, while adjusting the surface tension of the cured color development film and improving the flatness of the film layer during lamination.

4. The cured color-developing film according to claim 1, characterized in that, Of the two photoinitiators, the first is methyl benzoylformate (MBF), with a content of 1.0-2.0% by weight. MBF has high initiation activity in the 250-350nm UV band, which can quickly start the curing reaction and shorten the curing cycle. The second is diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide (TPO), with a content of 0.4-0.6% by weight. TPO is suitable for curing thicker films and can solve the problem of incomplete curing of deep films, ensuring uniform overall performance of the film.

5. The cured color-developing film according to claim 1, characterized in that, The filler is silica, preferably fumed silica, with a content of 2.0-3.0% by weight and a particle size of 10-50 nm. The silica can be uniformly dispersed in the film layer, which significantly improves the tensile strength and wear resistance of the cured color development film.

6. The cured color-developing film according to claim 1, characterized in that, The antioxidant is 2,6-di-tert-butyl-4-methylphenol (BHT), with a content of 0.05-0.10% by weight. BHT can inhibit the oxidative degradation of the cured color development film during long-term use, especially resisting the aging caused by high temperature and ultraviolet radiation during outdoor use in automobiles, and maintaining the stability of the film's appearance and performance.

7. The cured color-developing film according to claim 1, characterized in that, The pigment black is carbon black, with a content of 0.8-1.5% by weight; the carbon black has an oil absorption value of 100-150mL / 100g and a pH value of 6.0-8.0, which can be uniformly dispersed in the film layer, ensuring a consistent black appearance and avoiding film performance defects caused by carbon black agglomeration.

8. A method for producing automotive trim strips using a film instead of paint as described in any one of claims 1-7, characterized in that, The production equipment used includes a machine frame (1), a machine table (2), a product conveyor belt (3), a cooling air pipe (4), a glue-applying mold (5), a glue extruder (6), a release film layering mechanism (7), a drive mechanism (8), a buffer mechanism (9), a release film winding mechanism (10), a film roll (11), a machine back plate (12), and a film-applying mold (13). The machine table (2) is installed on the top of the machine frame (1), and the machine back plate (12) is installed on the top of the machine table (2). The film roll (11), buffer mechanism (9), drive mechanism (8), and release film are also included. The layering mechanism (7) is installed sequentially on the front of the equipment back plate (12) along the film conveying direction. The release film winding mechanism (10) is installed below the release film layering mechanism (7). The product conveyor belt (3) is installed on the top of the equipment table (2). The glue coating mold (5) is installed on one side of the top of the equipment frame (1) and connected to the output end of the extruder (6). The film-applying mold (13) is installed at the discharge end of the glue coating mold (5). The film-applying mold (13) faces the feed end of the product conveyor belt (3). The cooling air pipe (4) is installed above the feed end of the product conveyor belt (3).

9. A method for producing automotive trim strips using a film instead of paint as described in claim 8, characterized in that, The production method includes the following steps: S1: Preparation of Cured Color Development Film: Weigh out the UV curing resin, 3 kinds of reactive diluents, 2 kinds of photoinitiators, filler, antioxidant and pigment black according to the weight percentage, mix and stir evenly to form a film material, coat the film material onto the surface of the PET layer, and attach the release layer under the film material layer during coating, and then expose it to a UV light source (wavelength 200-400nm, irradiation intensity 80-120mW / cm). 2 Irradiate for 30-120 seconds to cure into a film. After curing, the color developing film is cut into strips and then wound onto a film roll (11). S2: Metal strip coating: Hot melt adhesive is put into the extruder (6) and the extruder (6) is started. The metal strip passes through the coating mold (5) laterally and the hot melt adhesive is evenly coated on the surface of the metal strip. S3: Start the drive mechanism (8) to drive the film roll (11) to unwind. The color developing film passes through the buffer mechanism (9) to adjust the tension and the release film layering mechanism (7) to remove the release film and is then transported into the bonding mold (13). The color developing film is bonded to the surface of the metal strip by hot melt adhesive and cooled and shaped by the cold air blown out by the cooling pipe (4). The decorative strip is transported out by the conveyor belt (2) to complete the production of the decorative strip.

Images