High-softness and high-wear-resistance PU artificial leather and preparation method thereof

Abstract

The invention discloses high-softness and high-wear-resistance PU artificial leather and a preparation method thereof, and relates to the technical field of artificial leather, the PU artificial leather comprises a base cloth layer, a bonding layer, a PU surface layer, a PU wear-resistant layer and a surface treatment layer which are arranged in sequence; the PU wear-resistant layer comprises the following raw materials in parts by weight: 100 parts of polyurethane resin A, 1-50 parts of a solvent A, 1-50 parts of a solvent B, 1-10 parts of a pigment and 1-10 parts of a wear-resistant agent; the polyurethane resin A is aliphatic polyurethane, and the modulus of the polyurethane resin A is 6-10 MPa. The PU wear-resistant layer and the surface treatment layer are sequentially arranged on the PU surface layer, high-modulus polyurethane resin is added into the wear-resistant layer, and the wear-resistant layer and the surface treatment layer can be subjected to cross-linking reaction, so that the strength of a surface material can be improved, the wear resistance of a whole product can be enhanced, direct contact between the surface treatment layer and the PU surface layer can be effectively avoided, and the service life of the product is prolonged. Therefore, the product has the advantages of wear resistance and high softness.

Description

Technical Field

[0001] The invention relates to the technical field of artificial leather, in particular to high-softness and high-wear-resistant PU artificial leather and a preparation method thereof. Background Art

[0002] In recent years, artificial leather has been widely used, especially PU artificial leather, which can be produced according to different needs and is widely used in luggage, clothing, furniture and vehicle decoration, meeting people's needs in different fields.

[0003] However, the existing PU artificial leather has a single base structure and poor structural stability. It is easy to deteriorate, crack, or even peel off in actual applications. In addition, its surface performance is poor, which greatly reduces the comfort of use. Although basic wear resistance is guaranteed by adjusting the materials and process methods, the softness of the product is greatly reduced and it cannot be used in vehicle decoration. Therefore, it is necessary to develop a PU artificial leather with both softness and wear resistance. Summary of the invention

[0004] Based on the technical problems existing in the background technology, the present invention proposes high-softness and high-wear-resistant PU artificial leather and a preparation method thereof. The PU artificial leather has excellent wear resistance and softness.

[0005] The invention provides a high-softness and high-wear-resistant PU artificial leather, comprising a base fabric layer, an adhesive layer, a PU surface layer, a PU wear-resistant layer and a surface treatment layer arranged in sequence;

[0006] The PU wear-resistant layer comprises the following raw materials in parts by weight: 100 parts of polyurethane resin A, 1-50 parts of solvent A, 1-50 parts of solvent B, 1-10 parts of colorant, and 1-10 parts of wear-resistant agent;

[0007] The polyurethane resin A is an aliphatic polyurethane with a modulus of 6-10 MPa.

[0008] Preferably, the PU surface layer comprises the following raw materials in parts by weight: 100 parts of polyurethane resin B, 1-50 parts of solvent A, 1-50 parts of solvent B, 0.1-1 part of cross-linking agent, 0.1-1 part of dispersant, and 1-10 parts of colorant.

[0009] Preferably, solvent A is one or more of butanone, N,N-dimethylformamide, and N,N-dimethyl sulfoxide.

[0010] Preferably, solvent B is one or more of N,N-dimethylformamide, N,N-dimethylacetamide and toluene.

[0011] Preferably, the crosslinking agent is one or more of acrylic resin, urea-formaldehyde, melamine resin and POSS crosslinking agent; the dispersant is one or more of N-methylformamide, 2-butylethanol and triethylenetetramine.

[0012] Preferably, the anti-wear agent is nano-alumina and / or nano-silicon dioxide.

[0013] Preferably, the surface treatment layer is a water-based polyurethane surface treatment agent.

[0014] The present invention provides a method for preparing a high-softness and high-wear-resistant PU artificial leather, wherein the PU artificial leather is as described above, and the method steps are as follows:

[0015] S1: Preparation of PU wear-resistant layer slurry and PU surface layer slurry;

[0016] S2: evenly coating the PU wear-resistant layer slurry on the release paper, and then drying it;

[0017] S3: evenly coating the PU surface slurry on the side of the PU wear-resistant layer away from the release paper, and then drying it;

[0018] S4: evenly coating the adhesive layer on the side of the surface layer away from the wear-resistant layer, laminating the base fabric with the adhesive layer, and then drying;

[0019] S5: Peeling off the release paper from the dried product, and then coating the PU wear-resistant layer with a water-based polyurethane surface treatment agent to form a surface treatment layer, thereby obtaining a high-softness and high-wear-resistant PU artificial leather.

[0020] Preferably, the drying temperature in S2 is 100-150°C and the time is 2-10 min; the drying temperature in S3 is 100-150°C and the time is 2-10 min; the drying temperature in S4 is 120-180°C and the time is 5-10 min.

[0021] Preferably, the coating thickness of the waterborne polyurethane surface treatment agent is 5-30 g / m 2 .

[0022] Beneficial technical effects of the present invention:

[0023] The present invention sequentially arranges a PU wear-resistant layer and a surface treatment layer on the PU surface layer, and adds a high-modulus polyurethane resin to the wear-resistant layer. A cross-linking reaction can occur between the wear-resistant layer and the treatment agent layer, which can not only improve the strength of the surface material and enhance the wear resistance of the overall product, but also effectively avoid direct contact between the surface treatment layer and the PU surface layer, which would lead to a decrease in the softness of the product, so that the product has both wear resistance and high softness. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1This is a schematic structural diagram of the high-softness and high-wear-resistant PU artificial leather proposed by the present invention.

[0025] In the figure: 1-base fabric layer, 2-adhesive layer, 3-PU surface layer, 4-PU wear-resistant layer, 5-surface treatment layer. DETAILED DESCRIPTION

[0026] The present invention will be further explained below in conjunction with specific embodiments.

[0027] In the embodiments of the present invention, unless otherwise specified, all equipment and raw materials can be purchased from the market or are commonly used in the industry, as shown in Table 1. The methods in the following embodiments, unless otherwise specified, are conventional methods in the art.

[0028] Table 1 Experimental raw materials

[0029] Example 1

[0030] The high-softness and high-wear-resistant PU artificial leather provided by the present invention comprises a surface treatment layer, a PU wear-resistant layer, a PU surface layer, a bonding layer and a base fabric layer which are arranged in sequence, wherein:

[0031] The PU wear-resistant layer comprises the following raw materials in parts by weight: 100 parts of polyurethane resin A (model BA-1930) with a modulus of 8 MPa, 40 parts of butanone, 20 parts of N,N-dimethylformamide (DMF), 6 parts of colorant HT-6810N, and 6 parts of nano-silicon dioxide;

[0032] The PU surface layer contains the following raw materials in parts by weight: 100 parts of polyurethane resin B (model AH-K100-1), 35 parts of butanone, 35 parts of DMF, 0.2 parts of crosslinking agent (acrylic resin YC-01), 0.2 parts of dispersant (2-butyl ethanol), and 6 parts of colorant HT-6810N.

[0033] The method for preparing the high-softness and high-wear-resistant PU artificial leather proposed by the present invention comprises the following steps:

[0034] S1: polyurethane resin A with a modulus of 8 MPa, butanone, DMF and colorant are uniformly mixed to form a PU wear-resistant layer slurry;

[0035] S2: The PU wear-resistant layer slurry is evenly coated on the release paper, and then dried at 120°C for 5 minutes;

[0036] S3: adding butanone, DMF, a crosslinking agent, a dispersant and a colorant to the polyurethane resin B in sequence, and stirring evenly to form a PU surface layer slurry;

[0037] S4: evenly coating the PU surface slurry on the side of the PU wear-resistant layer away from the release paper, and then drying it at 120° C. for 5 minutes;

[0038] S5: evenly coating the adhesive layer on the side of the surface layer away from the wear-resistant layer, and then drying it at 120°C for 90 seconds;

[0039] S6: Paste the base fabric on the side of the PU adhesive layer away from the PU surface layer, and dry it at 140°C for 8 minutes;

[0040] S7: Peel off the release paper from the dried product, and then coat the PU wear-resistant layer with 15g / m 2 The water-based polyurethane surface treatment agent (DS-9025) can obtain high softness and high wear resistance PU artificial leather.

[0041] Example 2

[0042] The method for preparing the high-softness and high-wear-resistant PU artificial leather proposed by the present invention is the same as that in Example 1. The difference between Example 2 and Example 1 is that:

[0043] The PU wear-resistant layer comprises the following raw materials in parts by weight: 100 parts of polyurethane resin A with a modulus of 7 MPa, 40 parts of butanone, 20 parts of DMF, 6 parts of colorant, and 6 parts of nano-silicon dioxide.

[0044] Example 3

[0045] The method for preparing the high-softness and high-wear-resistant PU artificial leather proposed by the present invention is the same as that in Example 1. The difference between Example 3 and Example 1 is that:

[0046] The PU wear-resistant layer comprises the following raw materials in parts by weight: 100 parts of polyurethane resin A with a modulus of 9 MPa, 40 parts of butanone, 20 parts of DMF, 6 parts of colorant, and 6 parts of nano-silicon dioxide.

[0047] Example 4

[0048] The method for preparing the high-softness and high-wear-resistant PU artificial leather proposed by the present invention is the same as that in Example 1. The difference between Example 4 and Example 1 is that:

[0049] The PU wear-resistant layer comprises the following raw materials in parts by weight: 100 parts of polyurethane resin A with a modulus of 10 MPa, 40 parts of butanone, 20 parts of DMF, 6 parts of colorant, and 6 parts of nano-silicon dioxide.

[0050] Example 5

[0051] The method for preparing the high-softness and high-wear-resistant PU artificial leather proposed by the present invention is the same as that in Example 1. The difference between Example 5 and Example 1 is that:

[0052] S7: Peel off the release paper from the dried product, and then coat the PU wear-resistant layer with 5g / m 2 By using the water-based polyurethane surface treatment agent, high softness and high wear resistance PU artificial leather can be obtained.

[0053] Example 6

[0054] The method for preparing the high-softness and high-wear-resistant PU artificial leather proposed by the present invention is the same as that in Example 1. The difference between Example 6 and Example 1 is that:

[0055] S7: Peel off the release paper from the dried product, and then coat the PU wear-resistant layer with 30g / m 2 By using the water-based polyurethane surface treatment agent, high softness and high wear resistance PU artificial leather can be obtained.

[0056] Comparative Example 1

[0057] The difference between Comparative Example 1 and Example 1 is that the PU artificial leather comprises a surface treatment layer, a PU surface layer, an adhesive layer and a base fabric layer arranged in sequence, wherein:

[0058] The PU surface layer comprises the following raw materials in parts by weight: 100 parts of polyurethane resin B, 35 parts of butanone, 35 parts of DMF, 0.2 parts of a crosslinking agent, 0.2 parts of a dispersant, and 6 parts of a colorant.

[0059] The method for preparing the high-softness and high-wear-resistant PU artificial leather proposed by the present invention comprises the following steps:

[0060] S1: adding butanone, DMF, crosslinking agent, dispersant and colorant to polyurethane resin B in sequence, and stirring evenly to form PU surface layer slurry;

[0061] S2: The PU surface slurry is evenly coated on the release paper, and then dried at 120°C for 5 minutes;

[0062] S3: Evenly apply the adhesive layer on the side of the PU surface layer away from the release paper, and then attach the base fabric, and dry it at 140°C for 8 minutes;

[0063] S4: Peel off the release paper from the dried product, and then coat the PU wear-resistant layer with 15g / m 2 By using the water-based polyurethane surface treatment agent, high softness and high wear resistance PU artificial leather can be obtained.

[0064] Comparative Example 2

[0065] The difference between Comparative Example 2 and Example 1 is that the PU artificial leather comprises a PU wear-resistant layer, a PU surface layer, an adhesive layer and a base fabric layer arranged in sequence, wherein:

[0066] The PU wear-resistant layer comprises the following raw materials in parts by weight: 100 parts of polyurethane resin A with a modulus of 8 MPa, 40 parts of butanone, 20 parts of DMF, 6 parts of colorant, and 6 parts of nano-silicon dioxide;

[0067] The PU surface layer comprises the following raw materials in parts by weight: 100 parts of polyurethane resin B, 35 parts of butanone, 35 parts of DMF, 0.2 parts of a crosslinking agent, 0.2 parts of a dispersant, and 6 parts of a colorant.

[0068] The method for preparing the high-softness and high-wear-resistant PU artificial leather proposed by the present invention comprises the following steps:

[0069] S1: polyurethane resin A with a modulus of 8 MPa, butanone, DMF and colorant are uniformly mixed to form a PU wear-resistant layer slurry;

[0070] S2: The PU wear-resistant layer slurry is evenly coated on the release paper, and then dried at 120°C for 5 minutes;

[0071] S3: adding butanone, DMF, a crosslinking agent, a dispersant and a colorant to the polyurethane resin B in sequence, and stirring evenly to form a PU surface layer slurry;

[0072] S4: evenly coating the PU surface slurry on the side of the PU wear-resistant layer away from the release paper, and then drying it at 120° C. for 5 minutes;

[0073] S5: Paste the base fabric on the side of the PU surface layer away from the PU wear-resistant layer, and dry it at 140°C for 8 minutes;

[0074] S6: Peel off the release paper from the dried product to obtain a highly soft and wear-resistant PU artificial leather.

[0075] The PU artificial leather prepared in Examples 1-6 and Comparative Examples 1-2 was tested for softness and wear resistance, and the results are shown in Table 2. The wear resistance test was based on the standard VDA230-211, and the softness test was based on the national standard GB / T 5155-2017.

[0076] Wear resistance test method: A sample with a diameter of 140 mm was prepared by a fully automatic hydraulic press, and the prepared PU artificial leather sample was tested on a Martindale fabric flat grinder to record the maximum number of friction times of the sample and the number of holes on the leather surface.

[0077] Softness test method: A sample with a diameter of 140 mm was prepared by a fully automatic hydraulic press, and the prepared PU artificial leather sample was tested on a digital leather softness tester to record the softness of the sample.

[0078] Table 2 Test of Softness and Wear Resistance of PU Artificial Leather

[0079] According to the analysis of the test results in Table 2, simply performing surface treatment on artificial leather or adding a single wear-resistant layer has limited effect on improving the overall wear resistance of the samples. However, when a composite modification scheme is adopted - that is, applying a wear-resistant layer on the surface of polyurethane artificial leather first and then performing surface treatment with waterborne polyurethane, the wear resistance of the samples is significantly improved, specifically manifested as a significant increase in the maximum number of friction resistance and a substantial reduction in the number of surface holes. This significant improvement mainly stems from the following two mechanisms: First, the polyurethane resin used in the wear-resistant layer has a relatively high modulus, which can significantly improve the wear resistance while still maintaining the soft characteristics of the substrate; Second, the carbodiimide structural aid introduced in the surface treatment layer can undergo a nucleophilic reaction with the carboxyl groups in the wear-resistant layer to generate cross-linked products with amide structures, thereby effectively enhancing the material strength. Although this high-modulus cross-linked product will slightly affect the softness of the material, the presence of the wear-resistant layer blocks the direct contact between the surface treatment agent and the substrate surface layer, ultimately achieving the optimization effect of significantly improving the wear resistance of artificial leather while minimizing the loss of softness.

[0080] Although the embodiments of the present application have been shown and described, for those of ordinary skill in the art, it can be understood that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principle and spirit of the present application. The scope of the present application is defined by the appended claims and their equivalents, and all should be included within the protection scope of the present application.

Claims

1. A high softness and high wear resistance PU artificial leather, characterized in that: It comprises a base fabric layer (1), an adhesive layer (2), a PU surface layer (3), a PU wear-resistant layer (4) and a surface treatment layer (5) which are arranged in sequence; The PU wear-resistant layer (4) comprises the following raw materials in parts by weight: 100 parts of polyurethane resin A, 1-50 parts of solvent A, 1-50 parts of solvent B, 1-10 parts of colorant, and 1-10 parts of wear-resistant agent; The polyurethane resin A is an aliphatic polyurethane with a modulus of 6-10 MPa.

2. The high softness and high wear resistance PU artificial leather according to claim 1, characterized in that: The PU surface layer comprises the following raw materials in parts by weight: 100 parts of polyurethane resin B, 1-50 parts of solvent A, 1-50 parts of solvent B, 0.1-1 part of crosslinking agent, 0.1-1 part of dispersant, and 1-10 parts of colorant.

3. The high softness and high wear resistance PU artificial leather according to claim 1 or 2, characterized in that: Solvent A is one or more of butanone, N,N-dimethylformamide and N,N-dimethyl sulfoxide.

4. The high softness and high wear resistance PU artificial leather according to claim 1 or 2, characterized in that: Solvent B is one or more of N,N-dimethylformamide, N,N-dimethylacetamide and toluene.

5. The high softness and high wear resistance PU artificial leather according to claim 2, characterized in that: The crosslinking agent is one or more of acrylic resin, urea-formaldehyde, melamine resin and POSS crosslinking agent; the dispersing agent is one or more of N-methylformamide, 2-butylethanol and triethylenetetramine.

6. The high softness and high wear resistance PU artificial leather according to claim 1, characterized in that: The anti-wear agent is nano-alumina and / or nano-silicon dioxide.

7. The high softness and high wear resistance PU artificial leather according to claim 1, characterized in that: The surface treatment layer is a water-based polyurethane surface treatment agent.

8. A method for preparing high-softness and high-wear-resistant PU artificial leather, the PU artificial leather as claimed in any one of claims 1 to 7, characterized in that: The steps are as follows: S1: Preparation of PU wear-resistant layer slurry and PU surface layer slurry; S2: evenly coating the PU wear-resistant layer slurry on the release paper, and then drying it; S3: evenly coating the PU surface slurry on the side of the PU wear-resistant layer away from the release paper, and then drying it; S4: evenly coating the adhesive layer on the side of the surface layer away from the wear-resistant layer, laminating the base fabric with the adhesive layer, and then drying; S5: Peeling off the release paper from the dried product, and then coating the PU wear-resistant layer with a water-based polyurethane surface treatment agent to form a surface treatment layer, thereby obtaining a high-softness and high-wear-resistant PU artificial leather.

9. The method for preparing the high-softness and high-wear-resistant PU artificial leather according to claim 8, characterized in that: The drying temperature of S2 is 100-150°C and the time is 2-10min; the drying temperature of S3 is 100-150°C and the time is 2-10min; the drying temperature of S4 is 120-180°C and the time is 5-10min.

10. The method for preparing high-softness and high-wear-resistant PU artificial leather according to claim 8, characterized in that: The coating thickness of waterborne polyurethane surface treatment agent is 5-30g / m 2 .

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