Leather composite board as well as preparation method and application thereof

Abstract

The invention relates to a leather composite board and a preparation method and application thereof. The leather composite board comprises a PU layer, an eyelet fabric, a PP adhesive film, a GMT board and a base fabric which are sequentially arranged in a stacked mode. The PU layer and the eyelet fabric are bonded by a binder A; and the eyelet fabric and the PP adhesive film are bonded by a binder B. The PP adhesive film is arranged between the eyelet fabric and the GMT board, so that the bonding capacity between the eyelet fabric and the GMT board is improved, the using amount of the adhesive B is reduced through the structural design, and the problem that the appearance of the leather composite board is affected due to the fact that the eyelet fabric absorbs a large amount of adhesive is solved.

Description

Technical Field

[0001] This invention relates to the field of automotive interior and exterior trim technology, and in particular to a leather composite panel, its preparation method, and its application. Background Technology

[0002] As the automotive industry rapidly develops towards lightweighting, comfort, and environmental friendliness, people's requirements for cars are no longer limited to transportation; they are increasingly focusing on the aesthetics, practicality, and comfort of the car's interior.

[0003] Thermoplastic polyurethane (PU) materials are widely used in the manufacture of automotive interior parts due to their excellent flexibility, abrasion resistance, aging resistance, and recyclability. To further enhance the tactile comfort and structural adaptability of interior parts, the industry commonly employs a composite surface structure of PU leather combined with mesh fabric. This structure combines the abrasion-resistant surface of PU leather with the breathability and cushioning properties of mesh fabric, and is widely used in key interior components such as dashboard coverings, door panels, and seat side bolsters. To further optimize the structural strength, lightweight effect, and cost control of interior parts, the industry generally uses an bonding process to combine the PU surface with glass fiber reinforced thermoplastic composite (GMT) to form composite interior parts that combine the structural support performance of GMT with the surface comfort performance of PU leather.

[0004] However, in the existing production process of composite interior parts, the reliability of the bond between GMT and PU skin remains a key technical bottleneck restricting the improvement of product quality. On the one hand, the surface of GMT material has a composite interface of glass fiber and thermoplastic resin, with low surface energy, and the inert surface of glass fiber makes it difficult to form an effective chemical bond with PU skin. At the same time, the interlacing gaps in the mesh fabric further aggravate the unevenness of the bonding interface, resulting in generally low bonding strength between the two. During long-term use of automobiles, under the influence of vibration, temperature changes, and external forces, this bonding interface is prone to delamination, warping, and other failures, seriously affecting the service life and safety of interior parts. On the other hand, the composite structure of PU skin and mesh fabric combines the porosity of PU skin with the interlacing structure of the mesh fabric. In traditional adhesive bonding processes, the adhesive applied to the bonding interface is not only absorbed by the pores of the PU skin but also seeps into the interlacing gaps of the mesh fabric, resulting in a severely insufficient effective adhesive layer thickness at the bonding interface. This prevents the formation of a uniform and continuous bonding layer, further reducing the bonding strength and affecting the product appearance.

[0005] Therefore, how to provide a leather composite board with good adhesion and excellent appearance has become an urgent problem to be solved. Summary of the Invention

[0006] To address the aforementioned technical problems, this invention provides a leather composite board, its preparation method, and its application. This leather composite board possesses excellent appearance and interfacial bonding properties, meeting the requirements of the high-end automotive interior market for aesthetics, practicality, and comfort.

[0007] To achieve this objective, the present invention adopts the following technical solution: In a first aspect, the present invention provides a leather composite board, the leather composite board comprising a PU layer, a mesh fabric, a PP film, a GMT board and a base fabric stacked sequentially; The PU layer is bonded to the mesh fabric by adhesive A; The mesh fabric and the PP film are bonded together by adhesive B.

[0008] This invention provides a leather composite board. By incorporating a mesh fabric laminated with a PU layer, the board's flexibility and breathability are enhanced, while surface stress is dispersed, preventing damage and cracking of the PU layer. The addition of a GMT board imparts excellent mechanical strength. However, due to its low surface energy, the GMT board has poor adhesion to the mesh fabric, typically requiring a large amount of adhesive. The mesh fabric's absorbent nature makes it difficult to ensure uniform adhesive distribution, leading to unevenness in the leather composite board's appearance. Therefore, this invention addresses this issue by placing a PP film between the mesh fabric and the GMT board. PP is a non-polar material with excellent interfacial compatibility with the GMT board. Furthermore, the PP film and mesh fabric can be effectively bonded with a small amount of adhesive, reducing the amount of adhesive required while maintaining adhesion between the mesh fabric and the GMT board. This avoids issues such as adhesive absorption by the mesh fabric affecting the appearance of the leather composite board.

[0009] Preferably, the PU layer and the mesh fabric are bonded together by adhesive A to form a PU composite layer.

[0010] Preferably, the mesh fabric is made of polyester fiber fabric.

[0011] Preferably, the base fabric is made of non-woven fabric.

[0012] Preferably, the basis weight of the PU composite layer is 500-1000 g / m². 2 For example, it could be 500 g / m 2 600 g / m 2 700 g / m 2 800 g / m 2 900 g / m 2 Or 1000 g / m 2 wait.

[0013] Preferably, the basis weight of the PP film is 100-200 g / m³. 2 For example, it could be 100 g / m 2 110 g / m 2 120g / m 2 130 g / m 2 140 g / m 2 150 g / m 2 160 g / m 2 170 g / m 2 180 g / m 2 190 g / m 2 Or 200 g / m 2 wait.

[0014] Preferably, the basis weight of the GMT board is 1500-2000 g / m². 2 For example, it could be 1500 g / m 2 1600 g / m 2 1700 g / m 2 1800 g / m 2 1900 g / m 2 Or 2000 g / m 2 wait.

[0015] Preferably, the adhesive A comprises PUR adhesive.

[0016] Preferably, the coating amount of adhesive A is 40-50 g / m². 2 For example, it could be 40 g / m 2 42 g / m 2 44 g / m 2 45 g / m 2 46 g / m 2 48 g / m 2 Or 50 g / m 2 wait.

[0017] Preferably, the adhesive B comprises a two-component waterborne polyurethane adhesive.

[0018] Preferably, the raw materials for preparing the two-component waterborne polyurethane adhesive include a base adhesive and a curing agent.

[0019] Preferably, the mass ratio of the main adhesive to the curing agent is (15-25):1, for example, it can be 15:1, 16:1, 18:1, 20:1, 22:1, 24:1 or 25:1.

[0020] Preferably, the coating amount of adhesive B is 90-110 g / m². 2For example, it could be 90 g / m 2 92 g / m 2 94g / m 2 95 g / m 2 96 g / m 2 98 g / m 2 100 g / m 2 102 g / m 2 104 g / m 2 105 g / m 2 106 g / m 2 108 g / m 2 Or 110 g / m 2 wait.

[0021] In a second aspect, the present invention provides a method for preparing a leather composite board as described in the first aspect, the method comprising the following steps: (1) Apply adhesive A to one side of the mesh fabric and then laminate it with the PU layer to obtain a PU composite layer; (2) The base fabric, GMT board and PP film are stacked in sequence and composited to obtain a composite structure of base fabric-GMT board-PP film; (3) In the composite structure of base fabric-GMT board-PP film, a portion of adhesive B is coated on the side of the PP film away from the GMT board, and another portion of adhesive B is coated on the side of the mesh fabric away from the PU layer in the PU composite layer. The portions coated with adhesive B are then laminated to obtain the leather composite board.

[0022] Steps (1) and (2) are not separate processes and can be performed simultaneously.

[0023] Preferably, the temperature of the composite process in step (1) is 115-125℃, for example, it can be 115℃, 116℃, 118℃, 120℃, 122℃, 124℃ or 125℃, etc., and the time is 40-80 s, for example, it can be 40 s, 50 s, 60 s, 70 s or 80 s, etc.

[0024] Preferably, the temperature of the composite process in step (2) is 160-170℃, for example, it can be 160℃, 162℃, 164℃, 165℃, 166℃, 168℃ or 170℃, etc., and the time is 40-80 s, for example, it can be 40 s, 50 s, 60 s, 70 s or 80 s, etc.

[0025] Preferably, the mass ratio of one part of adhesive B to another part of adhesive B in step (3) is 1:(0.8-1.2), for example, it can be 1:0.8, 1:0.9, 1:1, 1:1.1 or 1:1.2, etc.

[0026] Preferably, the compounding in step (3) is carried out under pressure.

[0027] Preferably, step (3) further includes an adhesive activation step before the composite process.

[0028] Preferably, the adhesive activation step includes independently heating the base fabric-GMT board-PP film composite structure coated with a portion of adhesive B and the PU composite layer coated with another portion of adhesive B at 50-70°C (e.g., 50°C, 55°C, 60°C, 65°C, or 70°C, etc.) for 150-200 s (e.g., 150 s, 160 s, 170 s, 180 s, 190 s, or 200 s, etc.).

[0029] Preferably, the compounding in step (3) is carried out under pressure.

[0030] Preferably, the pressurized pressure is 50-60 kPa, for example, it can be 50 kPa, 52 kPa, 54 kPa, 55 kPa, 56 kPa, 58 kPa or 60 kPa, etc.

[0031] Preferably, the temperature of the composite process in step (3) is 80-100℃, for example, 80℃, 85℃, 90℃, 95℃ or 100℃, and the time is 150-200 s, for example, 150 s, 160 s, 170 s, 180 s, 190 s or 200 s.

[0032] Thirdly, the present invention provides an application of the leather composite panel as described in the first aspect in automotive interiors.

[0033] Compared with the prior art, the present invention has at least the following beneficial effects: This invention improves the adhesion between the mesh fabric and the GMT board by setting a PP adhesive film between them, and reduces the amount of adhesive B used. It also avoids problems such as excessive adhesive absorption by the mesh fabric affecting the appearance of the leather composite board, thus meeting the requirements of the high-end automotive interior market for aesthetics, practicality, and comfort. Attached Figure Description

[0034] Figure 1 This is a schematic cross-sectional view of the leather composite board provided by the present invention; Among them, 1-PU layer, 2-mesh cloth, 3-PP film, 4-GMT board, 5-bottom cloth. Detailed Implementation

[0035] The technical solution of the present invention will be further described below with reference to the accompanying drawings and specific embodiments. However, the following examples are merely simplified examples of the present invention and do not represent or limit the scope of protection of the present invention. The scope of protection of the present invention is determined by the claims.

[0036] The specific information of the materials used in the following specific embodiments of the present invention is as follows: The base fabric, non-woven fabric, was purchased from Zhejiang Huajiang. GMT board, purchased from Zhejiang Huajiang; PP film, purchased from Zhejiang Huajiang; Non-woven fabric, purchased from Toronto, Wuxi; Plain slab, purchased from Toronto, Wuxi; Hot-rolled fabric, purchased from Toronto, Wuxi; Mesh fabric, 3D mesh polyester fiber, YH-1.3T-190G, purchased from Changshu Yinghong; PU layer, PU leather, purchased from Amway in Anhui; Adhesive A, PUR 7355, purchased from Hubei Yingseli; Adhesive B is obtained by mixing the main adhesive LM-06 (purchased from Suzhou Lvmiaohang) and the curing agent LM-HD100 (purchased from Suzhou Lvmiaohang) at a mass ratio of 20:1.

[0037] Example 1 This embodiment provides a leather composite board and its preparation method. The leather composite board includes a PU layer and a mesh fabric stacked sequentially (the PU layer and the mesh fabric are bonded together by adhesive A to form a PU composite layer with a basis weight of 770 g / m²). 2 ), PP film (gram weight 150 g / m 2 GMT board (weight 1800 g / m²) 2 ) and base fabric (non-woven fabric, purchased from Zhejiang Huajiang); The preparation method includes the following steps: (1) Apply adhesive A (coating amount of 45 g / m) to one side of the mesh fabric. 2 Then, it is laminated with the PU layer at 120℃ for 60 seconds to obtain the PU composite layer; (2) The base fabric, GMT board and PP film are stacked in sequence and laminated at 165℃ for 60 s to obtain the composite structure of base fabric-GMT board-PP film; (3) In the composite structure of base fabric-GMT board-PP film, adhesive B is applied to the side of the PP film away from the GMT board (the coating amount is 50 g / m). 2 In the PU composite layer, the mesh fabric is coated with another portion of adhesive B (coating amount is 50 g / m²) away from the PU layer. 2Then, the base fabric-GMT board-PP film composite structure coated with adhesive B and the PU composite layer coated with adhesive B are placed in a 60°C drying oven for 180 s for heat treatment. After the adhesive B is activated, the parts coated with adhesive B are bonded together and laminated at 55 kPa and 90°C for 160 s to obtain the leather composite board.

[0038] Comparative Example 1 This comparative example provides a leather composite board and its preparation method. The leather composite board includes a PU layer and a mesh fabric stacked sequentially (the PU layer and the mesh fabric are bonded together by adhesive A to form a PU composite layer with a basis weight of 770 g / m²). 2 ), non-woven fabric (purchased from Toronto, Wuxi), GMT board (grammage 1800 g / m²) 2 ) and base fabric (non-woven fabric, purchased from Zhejiang Huajiang).

[0039] The preparation method includes the following steps: (1) Apply adhesive A (coating amount of 45 g / m) to one side of the mesh fabric. 2 Then, it is laminated with the PU layer at 120℃ for 60 seconds to obtain the PU composite layer; (2) The base fabric, GMT board and non-woven fabric are stacked in sequence and composited at 165℃ for 60 s to obtain a composite structure of base fabric-GMT board-non-woven fabric; (3) Apply adhesive B (coating amount of 50 g / m) to the side of the nonwoven fabric away from the GMT board in the base fabric-GMT board-nonwoven fabric composite structure. 2 In the PU composite layer, the mesh fabric is coated with another portion of adhesive B (coating amount is 50 g / m²) away from the PU layer. 2 Then, the base fabric-GMT board-nonwoven fabric composite structure coated with adhesive B and the PU composite layer coated with adhesive B are placed in a 60°C drying oven for 180 s for heat treatment. After the adhesive B is activated, the parts coated with adhesive B are bonded together and laminated at 55 kPa and 90°C for 160 s to obtain the leather composite board.

[0040] Comparative Example 2 This comparative example provides a leather composite board and its preparation method. The leather composite board includes a PU layer and a mesh fabric stacked sequentially (the PU layer and the mesh fabric are bonded together by adhesive A to form a PU composite layer with a basis weight of 770 g / m²). 2 ), bare board, GMT board (grammage 1800 g / m²) 2 ) and base fabric (non-woven fabric, purchased from Zhejiang Huajiang).

[0041] The preparation method includes the following steps: (1) Apply adhesive A (coating amount of 45 g / m) to one side of the mesh fabric.2 Then, it is laminated with the PU layer at 120℃ for 60 seconds to obtain the PU composite layer; (2) The base fabric, GMT board and light board are stacked in sequence and composited at 165℃ for 60 s to obtain the base fabric-GMT board-light board composite structure; (3) In the composite structure of base fabric-GMT board-plain board, apply adhesive B (coating amount is 50 g / m) to the side of the plain board away from the GMT board. 2 In the PU composite layer, the mesh fabric is coated with another portion of adhesive B (coating amount is 50 g / m²) away from the PU layer. 2 Then, the base fabric-GMT board-plain board composite structure coated with adhesive B and the PU composite layer coated with adhesive B are placed in a 60°C drying oven for 180 s for heat treatment. After the adhesive B is activated, the parts coated with adhesive B are bonded together and laminated at 55 kPa and 90°C for 160 s to obtain the leather composite board.

[0042] Comparative Example 3 This comparative example provides a leather composite board and its preparation method. The leather composite board includes a PU layer and a mesh fabric stacked sequentially (the PU layer and the mesh fabric are bonded together by adhesive A to form a PU composite layer with a basis weight of 770 g / m²). 2 ), hot-rolled fabric, GMT board (grammage 1800 g / m²) 2 ) and base fabric (non-woven fabric, purchased from Zhejiang Huajiang).

[0043] The preparation method includes the following steps: (1) Apply adhesive A (coating amount of 45 g / m) to one side of the mesh fabric. 2 Then, it is laminated with the PU layer at 120℃ for 60 seconds to obtain the PU composite layer; (2) The base fabric, GMT board and hot-rolled fabric are stacked in sequence and composited at 165℃ for 60 s to obtain a composite structure of base fabric-GMT board-hot-rolled fabric; (3) In the composite structure of base fabric-GMT board-hot rolled fabric, adhesive B is applied to the side of the hot rolled fabric away from the GMT board (the coating amount is 50 g / m). 2 In the PU composite layer, the mesh fabric is coated with another portion of adhesive B (coating amount is 50 g / m²) away from the PU layer. 2 Then, the base fabric-GMT board-hot-rolled fabric composite structure coated with adhesive B and the PU composite layer coated with adhesive B are placed in a 60°C drying oven for 180 s for heat treatment. After the adhesive B is activated, the parts coated with adhesive B are bonded together and laminated at 55 kPa and 90°C for 160 s to obtain the leather composite board.

[0044] Test methods The following performance tests were performed on the leather composite panels provided in the examples and comparative examples: (1) Adhesion: The test shall be conducted in accordance with the standard Q / JQ 5569.2-2021. The test shall be conducted after standing for 24 hours at 23 ℃ and 65%RH. The requirement for composite products is that both the transverse and longitudinal adhesion strengths are ≥7.5 N / 5cm. (2) Appearance: The appearance must be flat and free from pits, unevenness, and other defects. The shrinkage of the product opening size must not exceed ±1.5 mm.

[0045] The test results are shown in Table 1: Table 1 The test results show that: (1) As can be seen from Example 1, the present invention improves the bonding ability between the mesh fabric and the GMT board by setting a PP adhesive film between the mesh fabric and the GMT board. The transverse bonding ability can reach 13 N / 5cm and the longitudinal bonding ability can reach 19 N / 5cm, which meets the product requirements that both the transverse bonding strength and the longitudinal bonding strength are ≥7.5 N / 5cm. Moreover, the product surface is good and the dimensions meet the requirements, which can meet the requirements of the high-end automotive interior market for aesthetics, practicality and comfort.

[0046] (2) As can be seen from Example 1 and Comparative Examples 1-3, by setting a PP film between the mesh fabric and the GMT board, the present invention can improve the bonding ability between the mesh fabric and the GMT board, reduce the amount of adhesive B, and avoid the mesh fabric absorbing a large amount of adhesive, thus affecting the appearance of the leather composite board. When non-woven fabric is used to replace the PP film, due to its adhesive absorption, the uniformity of adhesive B on the bonding surface cannot be guaranteed, and the bonding force with the mesh fabric is poor. When a smooth board is used to replace the PP film, it exhibits a fibrous texture after molding, which cannot be covered by the PU leather and mesh fabric, resulting in an uneven visual effect on the product surface. When a hot-rolled fabric is used to replace the PP film, although it does not have adhesive absorption, its heat shrinkage rate is large, and the leather composite board is prone to deformation after composite molding, resulting in unqualified product quality.

[0047] The applicant declares that the above description is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention fall within the protection and disclosure scope of the present invention.

Claims

1. A leather composite board, characterized in that, The leather composite board comprises a PU layer, a mesh fabric, a PP film, a GMT board, and a base fabric stacked in sequence. The PU layer is bonded to the mesh fabric by adhesive A; The mesh fabric and the PP film are bonded together by adhesive B.

2. The leather composite board according to claim 1, characterized in that, The PU layer and the mesh fabric are bonded together by adhesive A to form a PU composite layer; Preferably, the mesh fabric is made of polyester fiber fabric; Preferably, the base fabric is made of non-woven fabric.

3. The leather composite board according to claim 2, characterized in that, The PU composite layer has a basis weight of 500-1000 g / m². 2 .

4. The leather composite board according to any one of claims 1-3, characterized in that, The basis weight of the PP film is 100-200 g / m³. 2 .

5. The leather composite board according to any one of claims 1-4, characterized in that, The weight of the GMT board is 1500-2000 g / m². 2 .

6. The leather composite board according to any one of claims 1-5, characterized in that, The adhesive A includes PUR adhesive; Preferably, the coating amount of adhesive A is 40-50 g / m². 2 .

7. The leather composite board according to any one of claims 1-6, characterized in that, The adhesive B comprises a two-component waterborne polyurethane adhesive; Preferably, the raw materials for preparing the two-component waterborne polyurethane adhesive include a main adhesive and a curing agent; Preferably, the mass ratio of the main adhesive to the curing agent is (15-25):1; Preferably, the coating amount of adhesive B is 90-110 g / m². 2 .

8. A method for preparing a leather composite board as described in any one of claims 1-7, characterized in that, The preparation method includes the following steps: (1) Apply adhesive A to one side of the mesh fabric and then laminate it with the PU layer to obtain a PU composite layer; (2) The base fabric, GMT board and PP film are stacked in sequence and composited to obtain a composite structure of base fabric-GMT board-PP film; (3) In the composite structure of base fabric-GMT board-PP film, a portion of adhesive B is coated on the side of the PP film away from the GMT board, and another portion of adhesive B is coated on the side of the mesh fabric away from the PU layer in the PU composite layer. The portions coated with adhesive B are then laminated to obtain the leather composite board.

9. The method for preparing the leather composite board according to claim 8, characterized in that, The temperature for the composite process in step (1) is 115-125℃, and the time is 40-80 s; Preferably, the temperature for the composite process in step (2) is 160-170℃ and the time is 40-80 s; Preferably, the mass ratio of one part of adhesive B to another part of adhesive B in step (3) is 1:(0.8-1.2). Preferably, step (3) further includes an adhesive activation step before the composite process; Preferably, the adhesive activation step includes independently heating the base fabric-GMT board-PP film composite structure coated with a portion of adhesive B and the PU composite layer coated with another portion of adhesive B at 50-70°C for 150-200 s. Preferably, the compounding in step (3) is carried out under pressure; Preferably, the pressurized pressure is 50-60 kPa; Preferably, the temperature for the composite process in step (3) is 80-100℃ and the time is 150-200 s.

10. The application of a leather composite panel as described in any one of claims 1-7 in automotive interiors.

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