A car interior film with press resistance and resilience and a preparation method thereof

Abstract

The application relates to the technical field of high polymer materials, and particularly discloses a press-resistant and resilient automobile interior film and a preparation method thereof. The press-resistant and resilient automobile interior film comprises, from bottom to top, a foaming layer, a modified PVC skin layer and a surface coating layer, the raw materials of the modified PVC skin layer include 90-100 parts of PVC resin powder, 10-15 parts of ABS particles, 5-9 parts of an elastomer, 53-84 parts of a plasticizer, 13-30 parts of a stabilizer and 3-9 parts of titanium white powder according to weight parts, and the raw materials of the foaming layer include 55-75 parts of polypropylene and 15-23 parts of a foaming agent. The press-resistant and resilient automobile interior film can be used for preparing an automobile interior skin wrapping layer, has good texture, is resistant to pressing, has excellent resilience and has a relatively low preparation cost.

Description

Technical Field

[0001] This application relates to the field of polymer materials technology, and more specifically, it relates to a pressure-resistant and spring-rebound automotive interior film and its preparation method. Background Technology

[0002] With the development of science and technology, polyvinyl chloride (PVC) has become the most widely used environmentally friendly plastic material due to its excellent plasticity, mechanical properties, recyclability, flame retardancy, moisture resistance, and low price. PVC products are widely used in the automotive interior industry, serving as a major component of dashboards, door panels, roofs, seat cushions, wood veneers, sun visors, armrests, gear shift covers, and other interior components. Global demand for PVC is increasing year by year.

[0003] Currently, high-end automotive interiors utilize soft-touch materials. The polymer resin used in the surface layer is mostly reinforced PP, ABS / PC, or a blend of styrene / maleic anhydride (SMA), while the foam layer primarily uses polyurethane foam (PUFoam) or polypropylene foam (PPF). Hard-touch interiors have a rigid surface and are typically a single-layer structure directly injection molded. They often use modified PP or TPO materials and have a less premium feel than soft-touch interiors. They are mostly used in trucks, buses, and economy cars. Soft-touch interiors offer a comfortable and luxurious feel while also absorbing impact energy and noise, thus they are commonly used in mid-to-high-end cars.

[0004] In recent years, more and more car models have adopted soft-touch interior materials, and OEMs also hope to use soft-touch interior materials in mid-to-low-end models, but are often unable to do so due to cost constraints. Regarding the aforementioned technologies, the inventors also discovered that current soft-touch interior materials still have shortcomings in weather resistance and texture, making it difficult to meet consumers' requirements for the comfort of car interiors. Summary of the Invention

[0005] To improve the pressure resistance and resilience of automotive interior materials and enhance their texture, this application provides a pressure-resistant and resilience-resilient automotive interior film and its preparation method.

[0006] In a first aspect, this application provides a pressure-resistant and spring-rebound automotive interior film, employing the following technical solution:

[0007] A pressure-resistant and resilient automotive interior film comprises, from bottom to top, a foaming layer, a modified PVC skin layer, and a surface coating layer. By weight, the modified PVC skin layer comprises 90-100 parts PVC resin powder, 10-15 parts ABS granules, 5-9 parts elastomer, 53-84 parts plasticizer, 13-30 parts stabilizer, and 3-9 parts titanium dioxide. The foaming layer comprises 55-75 parts polypropylene and 15-23 parts foaming agent.

[0008] By adopting the above technical solution, the automotive interior film of this application forms a three-layer structure consisting of a polypropylene foam layer, a modified PVC skin layer, and a surface coating layer. The polypropylene foam layer gives the film lightweight and cushioning properties, the modified PVC skin layer gives the film weather resistance, pressure resistance, and resilience, and the surface coating layer gives the film good wear and scratch resistance and a pleasant feel.

[0009] Using PVC as the base material and ABS as the reinforcement, an elastomer is added to adjust flexibility and promote the absorption and dispersion of external impact forces, forming a ternary modified PVC skin layer of PVC-ABS-elastomer. This effectively combines the weather resistance of PVC, the strength of ABS, and the flexibility of elastomer, giving automotive interior film materials excellent pressure resistance and resilience. The raw material costs of this application are low, significantly reducing production costs, and the finished product has low odor, meeting the odor requirements of OEMs.

[0010] Optionally, the plasticizer comprises, by weight, 45-60 parts of octyl epoxide stearate, 3-9 parts of diethyl phthalate and 5-15 parts of epoxide soybean oil.

[0011] By adopting the above technical solutions, octyl epoxide stearate, diethyl phthalate, and natural plasticizer epoxide soybean oil all have good compatibility with PVC matrix. All three have low odor, which can effectively improve the flexibility and extensibility of automotive interior films, while also helping to reduce the odor of automotive interior films.

[0012] Optionally, the foaming agent comprises 10-15 parts by weight of azobisformamide and 5-8 parts by weight of diethyl azodicarbonate.

[0013] By adopting the above technical solution, the combination of azobisformamide and diethyl azodicarbonate can optimize the performance of the foaming system, reduce the emission of harmful gases, improve the foaming quality, and make it more environmentally friendly and mild.

[0014] Optionally, the stabilizer comprises 10-30 parts by weight of calcium carbonate whiskers and 3-8 parts by weight of calcium sulfate whiskers.

[0015] By adopting the above technical solution, whiskers, being one-dimensional materials, possess high strength and modulus, and can be uniformly dispersed in composite materials, thereby effectively improving the mechanical properties of the composite materials. Both calcium carbonate whiskers and calcium sulfate whiskers are needle-like materials, overcoming the weakness of high cost in traditional reinforcing materials, while also possessing excellent strength and heat insulation properties, effectively improving the stability and heat resistance of modified PVC skin layers.

[0016] Optionally, the elastomer is a thermoplastic polyurethane elastomer.

[0017] Optionally, the surface coating is formed by a coating agent, which is a polycarbonate material selected from... Polycarbonate polyol TBC1000.

[0018] By adopting the above technical solution, polycarbonate material has excellent wear resistance. As a coating agent, it helps to improve the surface texture and feel of automotive interior film materials, while ensuring strong adhesion and excellent wear and scratch resistance between the coating layer and the modified PVC skin layer.

[0019] Secondly, this application provides a method for preparing a pressure-resistant and spring-rebound automotive interior film, employing the following technical solution:

[0020] A method for preparing a pressure-resistant and resilient automotive interior film includes the following steps:

[0021] S1: Weigh PVC resin powder, ABS granules, elastomer, plasticizer, stabilizer and titanium dioxide according to the weight parts, mix them, and then melt extrude, cast into a film, and cool and mold to obtain a modified PVC skin layer.

[0022] S2: Polypropylene and foaming agent are blended, then melt extruded, foamed, molded, and cooled to obtain a foamed layer. The modified PVC skin layer is then bonded to the foamed layer with an adhesive.

[0023] S3: Apply a coating agent by roller coating on the side of the modified PVC skin layer away from the foam layer, and after drying, form a surface coating layer.

[0024] By adopting the above technical solution, the preparation process of this application is simple, combining the weather resistance of PVC, the strength of ABS, the flexibility of elastomers, and the lightweight and cushioning properties of the foam layer, so that the final automotive interior film has excellent comprehensive performance, can be mass-produced, and helps to improve production efficiency and reduce production costs.

[0025] By bonding the modified PVC skin layer to the foam layer with an adhesive, a strong bond between the two layers can be ensured, while maintaining overall flexibility and durability.

[0026] Optionally, the thickness of the foamed layer is 2.5-3 mm, the thickness of the modified PVC skin layer is 0.8-1.6 mm, and the thickness of the surface coating layer is 0.01-0.05 mm.

[0027] By adopting the above technical solutions, precise control of the thickness of each layer helps to ensure the pressure resistance, resilience, and appearance of automotive interior film materials.

[0028] Optionally, the adhesive is selected from Huirui PP adhesive HR-735.

[0029] By adopting the above technical solution, Huirui PP adhesive HR-735, as an adhesive, has high bonding strength between PP and PVC. After curing, it is tough, does not harden, and is shatter resistant. It can provide good bonding effect and meet environmental protection requirements, ensuring a tight bond between the foam layer and the modified PVC skin layer, and improving the overall stability and durability of the material.

[0030] In summary, this application has the following beneficial effects:

[0031] 1. This application adopts a three-layer composite structure consisting of a polypropylene foam layer, a modified PVC skin layer, and a polycarbonate material surface coating. It combines the lightweight and cushioning properties of the polypropylene foam layer, the weather resistance of PVC, the strength and flexibility of ABS and elastomers, and the wear and scratch resistance of polycarbonate materials. The resulting automotive interior film has a soft feel and good rebound effect when pressed, and it also has good weather resistance. When applied to automotive interiors such as dashboards, door panels, and upper parts of door panels, it can improve the hard surface of plastic dashboards and protective panels used alone, giving people a comfortable and high-end feeling.

[0032] 2. The raw materials used in this application are all low in cost and have low odor, which can be widely produced and applied, making up for the shortcomings of traditional soft interior materials that cannot be widely used due to cost limitations. At the same time, it can meet the requirements of major OEMs for the odor and emission of automotive interiors. Detailed Implementation

[0033] The following embodiments provide a further detailed description of this application.

[0034] raw material

[0035] Unless otherwise specified, the raw materials used in the embodiments and comparative examples in this application are all commercially available products, specifically: PVC resin powder with a degree of polymerization of 1300.

[0036] ABS granules, selected from PetroChina, 0215E;

[0037] Thermoplastic polyurethane elastomer, selected from Wanhua Chemical, WHT-6290;

[0038] Octyl epoxy stearate, selected from Guangzhou Shanshui Chemical Co., Ltd., Lankroflex ED6;

[0039] Epoxidized soybean oil, selected from Fengyi New Materials, PVC plasticizer 001;

[0040] Polypropylene, selected from Sinopec Maoming, HT9025NX;

[0041] Azobisformamide, selected from Wuhan Kanos Technology Co., Ltd., CAS: 123-77-3;

[0042] Diethyl azodicarbonate, selected from Hubei Fangde New Materials Co., Ltd., CAS: 1972-28-7;

[0043] Calcium carbonate whiskers, purity ≥98%, length 30±5μm, aspect ratio 25±5;

[0044] Calcium carbonate granules, purity ≥99%, average particle size 200 mesh;

[0045] Calcium sulfate whiskers, purity ≥98%, length 200±20μm, aspect ratio 20±5;

[0046] Calcium sulfate granules, purity ≥99%, average particle size 200 mesh;

[0047] The adhesive is selected from Huirui PP adhesive, HR-735;

[0048] Waterborne polyurethane coating agent, selected from Ruilin, RL-63012A;

[0049] The coating agent is a polycarbonate material, selected from... Polycarbonate polyol TBC1000.

[0050] Example

[0051] Example 1

[0052] A pressure-resistant and resilient automotive interior film comprises, from bottom to top, a foam layer, a modified PVC skin layer, and a surface coating layer. The raw materials and amounts of the foam layer and the modified PVC skin layer are shown in Table 1. The elastomer is a thermoplastic polyurethane elastomer, and the surface coating layer is formed by a polycarbonate coating agent.

[0053] Table 1

[0054]

[0055]

[0056] The method for preparing the above-mentioned pressure-resistant and spring-rebound automotive interior film includes the following steps:

[0057] S1: Weigh out PVC resin powder, ABS granules, elastomer, plasticizer, stabilizer and titanium dioxide according to the weight parts, mix them, melt extrusion, cast film, and cool to form a modified PVC skin layer with a thickness of 1.3mm.

[0058] S2: Polypropylene and foaming agent are blended, then melt extruded, foamed, molded, and cooled to obtain a foamed layer with a thickness of 2.6 mm. The modified PVC skin layer is then bonded to the foamed layer with an adhesive.

[0059] S3: Apply a coating agent of polycarbonate material to the side of the modified PVC skin layer away from the foam layer by roller coating. After drying, a surface coating layer with a thickness of 0.01mm is formed, resulting in an automotive interior film consisting of a foam layer, a modified PVC skin layer, and a surface coating layer from bottom to top.

[0060] Example 2

[0061] A pressure-resistant and resilient automotive interior film differs from Example 1 in that the raw materials and amounts of the foam layer and modified PVC skin layer are shown in Table 1.

[0062] The method for preparing the above-mentioned pressure-resistant and spring-rebound automotive interior film includes the following steps:

[0063] S1: Weigh out PVC resin powder, ABS granules, elastomer, plasticizer, stabilizer and titanium dioxide according to the weight parts, mix them, melt extrusion, cast film, and cool to form a modified PVC skin layer with a thickness of 1.6mm.

[0064] S2: Polypropylene and foaming agent are blended, then melt extruded and foamed, molded and cooled to obtain a foamed layer with a thickness of 2.5mm. The modified PVC skin layer is then bonded to the foamed layer with an adhesive.

[0065] S3: Apply a coating agent of polycarbonate material to the side of the modified PVC skin layer away from the foam layer by roller coating. After drying, a surface coating layer with a thickness of 0.03mm is formed, resulting in an automotive interior film consisting of a foam layer, a modified PVC skin layer, and a surface coating layer from bottom to top.

[0066] Example 3

[0067] A pressure-resistant and resilient automotive interior film differs from Example 1 in that the raw materials and amounts of the foam layer and modified PVC skin layer are shown in Table 1.

[0068] The method for preparing the above-mentioned pressure-resistant and spring-rebound automotive interior film includes the following steps:

[0069] S1: Weigh out PVC resin powder, ABS granules, elastomer, plasticizer, stabilizer and titanium dioxide according to the weight parts, mix them, melt extrusion, cast film, and cool to form a modified PVC skin layer with a thickness of 3mm.

[0070] S2: Polypropylene and foaming agent are blended, then melt extruded and foamed, molded and cooled to obtain a foamed layer with a thickness of 1mm. The modified PVC skin layer is then bonded to the foamed layer with an adhesive.

[0071] S3: Apply a coating agent of polycarbonate material to the side of the modified PVC skin layer away from the foam layer by roller coating. After drying, a surface coating layer with a thickness of 0.04 mm is formed, resulting in an automotive interior film consisting of a foam layer, a modified PVC skin layer, and a surface coating layer from bottom to top.

[0072] Example 4

[0073] A pressure-resistant and resilient automotive interior film differs from Example 1 in that the raw materials and amounts of the foam layer and modified PVC skin layer are shown in Table 1.

[0074] The method for preparing the above-mentioned pressure-resistant and spring-rebound automotive interior film includes the following steps:

[0075] S1: Weigh out PVC resin powder, ABS granules, elastomer, plasticizer, stabilizer and titanium dioxide according to the weight parts, mix them, melt extrusion, cast film, and cool to form a modified PVC skin layer with a thickness of 0.8mm.

[0076] S2: Polypropylene and foaming agent are blended, then melt extruded and foamed, molded and cooled to obtain a foamed layer with a thickness of 2.7mm. The modified PVC skin layer is then bonded to the foamed layer with an adhesive.

[0077] S3: Apply a coating agent of polycarbonate material to the side of the modified PVC skin layer away from the foam layer by roller coating. After drying, a surface coating layer with a thickness of 0.05mm is formed, resulting in an automotive interior film consisting of a foam layer, a modified PVC skin layer, and a surface coating layer from bottom to top.

[0078] Example 5

[0079] A pressure-resistant and resilient automotive interior film differs from Example 1 in that the plasticizer for the modified PVC surface layer is only octyl epoxy stearate, while the other steps are the same as in Example 1.

[0080] Example 6

[0081] A pressure-resistant and resilient automotive interior film differs from Example 1 in that the plasticizer for the modified PVC surface layer is only diethyl phthalate, while the other steps are the same as in Example 1.

[0082] Example 7

[0083] A pressure-resistant and resilient automotive interior film differs from Example 1 in that the plasticizer for the modified PVC surface layer is only epoxidized soybean oil, while the other steps are the same as in Example 1.

[0084] Example 8

[0085] A pressure-resistant and resilient automotive interior film differs from Example 1 in that the calcium carbonate whiskers in the modified PVC surface layer raw material stabilizer are replaced with an equal mass of calcium carbonate particles, and the calcium sulfate whiskers are replaced with an equal mass of calcium sulfate particles. All other steps are the same as in Example 1.

[0086] Example 9

[0087] A pressure-resistant and resilient automotive interior film differs from Example 1 in that the surface coating is formed by an aqueous polyurethane coating agent, while all other steps are the same as in Example 1.

[0088] Comparative Example

[0089] Comparative Example 1

[0090] A pressure-resistant and resilient automotive interior film differs from Example 1 in that the ABS particles in the modified PVC surface layer raw material are replaced with an equal mass of PVC resin powder, while the other steps are the same as in Example 1.

[0091] Comparative Example 2

[0092] A pressure-resistant and resilient automotive interior film differs from Example 1 in that the elastomer in the modified PVC surface layer raw material is replaced with an equal mass of PVC resin powder, while all other steps are the same as in Example 1.

[0093] Comparative Example 3

[0094] A pressure-resistant and resilient automotive interior film, differing from Example 1 in that its preparation method includes the following steps:

[0095] S1: Polypropylene and a foaming agent are blended, then melt-extruded, foamed, molded, and cooled to obtain a foamed layer with a thickness of 2.6 mm.

[0096] S2: Weigh PVC resin powder, ABS granules, elastomer, plasticizer, stabilizer and titanium dioxide according to the weight parts, blend them, and then melt extrude and cast them into a film. After cooling and molding, a modified PVC skin layer with a thickness of 1.3mm is obtained. The foam layer is thermally bonded to one side of the modified PVC skin layer to form a substrate composed of the foam layer and the modified PVC skin layer.

[0097] S3: Apply a coating agent of polycarbonate material to the side of the modified PVC skin layer away from the foam layer by roller coating. After drying, a surface coating layer with a thickness of 0.01mm is formed, resulting in an automotive interior film consisting of a foam layer, a modified PVC skin layer, and a surface coating layer from bottom to top.

[0098] Performance testing

[0099] The following relevant performance tests were conducted on the pressure-resistant and springback-resistant automotive interior films obtained in Examples 1-9 and Comparative Examples 1-3. Each test was conducted 3 times, and the average value was taken as the final result and recorded in Table 2.

[0100] 1. Peel Strength: The peel strength of the foamed layer and modified PVC outer layer of the above-mentioned automotive interior film was tested at room temperature, after environmental cycling, and after heat treatment, in accordance with the standards and specifications of ISO 2411. The acceptance criteria are as follows:

[0101] Peel strength at room temperature: ≥10N / 5cm or 100% foam tear strength;

[0102] Peel strength after environmental cycling: ≥8N / 5cm or 100% foam tear strength;

[0103] Peel strength after heat treatment: ≥8N / 5cm or 100% foam tear strength.

[0104] 2. Odor: The odor level of the above-mentioned automotive interior films was tested in accordance with the standards and regulations of PV3900.

[0105] 3. Scratch resistance: The above-mentioned automotive interior film was subjected to a cross-cut test in accordance with the German Volkswagen PV3952 standard. The sample size was 50mm×50mm×3.2mm, the load was 10N, and the color difference L value change ΔL before and after the cross-cut test was measured with a colorimeter. The smaller the ΔL value, the better the scratch resistance of the surface material.

[0106] 4. Resilience: The resilience of the above-mentioned automotive interior film was tested in accordance with the relevant standards and regulations of GB / T 6670.

[0107] 5. Tensile strength: The tensile strength of the above-mentioned automotive interior films was tested in accordance with the relevant standards and regulations of GB / T 1040.

[0108] Table 2

[0109]

[0110] As can be seen from the performance test results in Table 2, the pressure-resistant and rebound-resistant automotive interior film of this application has good resilience and excellent mechanical properties, and its odor meets the standards. It also has good wear and scratch resistance and can be used as a soft material to prepare the surface wrapping material of high-end automotive interiors. It can give the automotive interiors better texture and durability to meet consumers' requirements for the comfort of using automotive interiors.

[0111] Meanwhile, the raw materials used in this application are all low in cost, enabling widespread production and application, thus overcoming the shortcomings of traditional soft interior materials which are limited by cost and cannot be widely used.

[0112] Based on the performance test results of Examples 1-4, Example 9, and Comparative Examples 1-3, it can be seen that the present application adopts a three-layer composite structure consisting of a polypropylene foam layer, a modified PVC skin layer, and a polycarbonate material surface coating layer. This structure combines the lightweight and cushioning properties of the polypropylene foam layer, the weather resistance of PVC, the strength of ABS, the flexibility of the elastomer, and the wear and scratch resistance of the polycarbonate material. The resulting automotive interior film has a flexible feel and a good pressing and rebound effect, as well as excellent mechanical properties and is more durable.

[0113] Compared to thermal bonding, bonding with a specific adhesive significantly improves the adhesion strength between the non-polar polypropylene foam layer and the modified PVC skin layer, thus ensuring the normal use of the product.

[0114] According to the performance test results of Examples 1-4 and Examples 5-8, octyl epoxy stearate, diethyl phthalate, and natural plasticizer epoxy soybean oil all have good compatibility with PVC matrix and low odor. When used in combination, they can effectively improve the flexibility and extensibility of automotive interior films, while enhancing the mechanical properties of the films and minimizing the odor of the films.

[0115] The use of one-dimensional whisker-shaped calcium carbonate and calcium sulfate, compared to granular materials, can more effectively improve the mechanical properties, wear resistance, and scratch resistance of automotive interior films. As a stabilizer, it ensures the weather resistance and stability of the modified PVC skin layer and avoids the migration of plasticizers and other raw materials.

[0116] This specific embodiment is merely an explanation of this application and is not intended to limit it. After reading this specification, those skilled in the art can make modifications to this embodiment without contributing any inventive step, but such modifications are protected by patent law as long as they fall within the scope of the claims of this application.

Claims

1. A press-resistant and resilient automotive interior film, characterized by, From bottom to top, the foaming layer, the modified PVC skin layer and the surface coating layer are sequentially included, according to weight parts, the raw materials of the modified PVC skin layer include 90-100 parts of PVC resin powder, 10-15 parts of ABS particles, 5-9 parts of thermoplastic polyurethane elastomer, 53-84 parts of plasticizer, 13-30 parts of stabilizer and 3-9 parts of titanium white powder; According to weight parts, the raw materials of the foaming layer include 55-75 parts of polypropylene and 15-23 parts of foaming agent; According to weight parts, the plasticizer includes 45-60 parts of octyl epoxy stearate, 3-9 parts of diethyl phthalate and 5-15 parts of epoxy soybean oil; According to weight parts, the stabilizer includes 10-24 parts of calcium carbonate whisker and 3-8 parts of calcium sulfate whisker, the length of the calcium carbonate whisker is 30±5 μm, the aspect ratio is 25±5, the length of the calcium sulfate whisker is 200±20 μm, and the aspect ratio is 20±5.

2. The press resistant resilient automotive interior film of claim 1, wherein, According to weight parts, the foaming agent includes 10-15 parts of azobisformamide and 5-8 parts of azodicarbonic acid diethyl ester.

3. The press resistant resilient automotive interior film of claim 1, wherein, The surface coating layer is formed by a finishing agent, and the finishing agent is a polycarbonate material, specifically Mofltive® polycarbonate polyol TBC1000.

4. A method for preparing a pressure-resistant and resilient automotive interior film according to any one of claims 1-3, characterized in that, The method includes the following steps: S1: according to weight parts, PVC resin powder, ABS particles, thermoplastic polyurethane elastomer, plasticizer, stabilizer and titanium white powder are weighed and mixed, then melt extruded and flow casted into a film, and after cooling and forming, a modified PVC skin layer is obtained; S2: polypropylene and foaming agent are blended, then melt extruded, foamed, formed and cooled to obtain a foaming layer, and then the modified PVC skin layer and the foaming layer are bonded by an adhesive; S3: the finishing agent is coated on the side of the modified PVC skin layer away from the foaming layer in the form of roller coating, and after drying, a surface coating layer is formed, and the process is completed.

5. The method for preparing the pressure-resistant and spring-rebound automotive interior film according to claim 4, characterized in that, The thickness of the foaming layer is 2.5-3 mm, the thickness of the modified PVC skin layer is 0.8-1.6 mm, and the thickness of the surface coating layer is 0.01-0.05 mm.

6. The method for preparing the pressure-resistant and spring-rebound automotive interior film according to claim 4, characterized in that, The adhesive is Huirui PP adhesive HR-735.

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