Environment-friendly protein leather for electronic products and preparation method thereof

Abstract

The present application relates to a kind of environmental protection protein leather for electronic product, it includes water-based surface layer, water-based intermediate layer, solvent-free foaming layer, base cloth layer from top to bottom sequentially;The solvent-free foaming slurry prepared from the mixture of A material and B material of solvent-free foaming layer, wherein, the A material is prepared from the following components by mass fraction:100 parts of polyester polyol prepolymer, 1-2 parts of deionized water, 0-40 parts of filler, 0.1-0.5 parts of catalyst, 0.5-2.0 parts of foaming agent;The B material is isocyanate prepolymer.The present application adds deionized water in solvent-free foaming layer, adjusts the dosage of catalyst at the same time, makes that foaming is uniform, soft feeling, to develop similar traditional wet method protein skin solvent-free product, can be used as the environmental protection alternative product of traditional wet method protein skin, can be widely used in high-grade earphone cover, VR eyeshade and so on product.

Description

Technical Field

[0001] This invention relates to the field of synthetic leather technology, and in particular to an environmentally friendly protein leather synthetic leather for electronic products and its preparation method. Background Technology

[0002] Headphones and VR headsets, as accessories to electronic products, have become necessities for leisure and entertainment, favored by global international brands and forming a relatively complete industrial chain. Among them, headphone headsets, with their comfort and breathability, have won consumer favor, resulting in strong market demand. Simultaneously, with the rise of the metaverse concept and the popularization of VR technology, more and more ordinary consumers are able to access VR headsets, creating a completely new market with broad prospects.

[0003] Currently, headphone earcups on the market are mainly divided into genuine leather earcups and synthetic leather earcups based on their materials. While genuine leather earcups are soft and skin-friendly, genuine leather resources are limited, expensive, have some poor physical and mechanical properties, and require stringent environmental standards for processing, resulting in a low cost-performance ratio. VR headset covers are currently primarily made of textiles, which offer good breathability. However, the base fabric has poor resistance to dirt and is prone to bacterial growth, potentially causing skin irritation with prolonged wear. Polyurethane synthetic leather is easy to clean and has a more upscale appearance than textiles. However, conventional polyurethane synthetic leather is generally made from soft polyurethane with DMF as the solvent, resulting in poor hydrolysis resistance, uncomfortable comfort, and difficulty in meeting environmental standards. Summary of the Invention

[0004] Based on this, and addressing the technical problems existing in the prior art, the purpose of this invention is to provide an environmentally friendly protein leather synthetic leather for electronic products and its preparation method. This environmentally friendly protein leather synthetic leather for electronic products adopts a four-way elastic base fabric combined with a water-based solvent-free process to produce an environmentally friendly synthetic leather product with four-way elasticity. By adjusting the water-based surface layer and the solvent-free formula, the synthetic leather is given a soft hand feel and a skin-friendly touch. A polyurethane synthetic leather suitable for wearable electronic devices such as headphone covers and VR glasses covers is produced. It has excellent shaping and processing performance, clear texture, does not produce wrinkles, and has a skin-friendly and soft hand feel.

[0005] To achieve the above objectives, the present invention adopts the following technical solution.

[0006] This invention provides an environmentally friendly protein leather synthetic leather for electronic products, comprising, from top to bottom, an aqueous top layer, an aqueous intermediate layer, a solvent-free foaming layer, and a base fabric layer; the solvent-free foaming layer is prepared from a solvent-free foaming slurry composed of a mixture of component A and component B, wherein component A is prepared from the following components in parts by weight: 100 parts polyester polyol prepolymer, 1-2 parts deionized water, 0-40 parts filler, 0.1-0.5 parts catalyst, and 0.5-2.0 parts foaming agent; component B is an isocyanate prepolymer.

[0007] As a further improvement to the above-mentioned solution of the present invention, in the solvent-free foaming slurry, the mass ratio of component A to component B is 100:40-50.

[0008] As a further improvement of the above-mentioned solution of the present invention, the water-based surface layer is prepared by water-based surface layer slurry, which is prepared by the following components in parts by weight: 100 parts water-based polyurethane, 40-80 parts deionized water, 0.5-1.5 parts water-based thickener, 5-20 parts water-based color paste, 0.5-1.2 parts water-based leveling agent, and 1-2 parts organosilicon.

[0009] As a further improvement of the above-mentioned solution of the present invention, the water-based intermediate layer is prepared by water-based intermediate layer slurry, which is prepared by the following components in parts by weight: 100 parts water-based polyurethane, 40-80 parts deionized water, 0.5-1.5 parts water-based thickener, 0.5-1.2 parts leveling agent, and 1-2 parts water-based curing agent.

[0010] As a further improvement to the above-mentioned solution of the present invention, the filler is at least one of ultrafine lignin and ultrafine pulp powder.

[0011] This invention also provides a method for preparing environmentally friendly protein leather synthetic leather for electronic products as described above, comprising the following steps:

[0012] S1. Coat the release paper with an aqueous surface layer slurry, and dry it to form an aqueous surface layer;

[0013] S2. A water-based intermediate layer slurry is coated on the water-based surface layer and dried to form a water-based intermediate layer;

[0014] S3. A solvent-free foaming slurry is coated onto the aqueous intermediate layer and pre-dried to form a solvent-free foaming layer;

[0015] S4. The base fabric is bonded to the solvent-free foaming layer, cured, cooled, and the release paper is peeled off to obtain water-based solvent-free polyurethane synthetic leather.

[0016] As a further improvement to the above-mentioned solution of the present invention, in step S1, the coating thickness of the water-based surface slurry is 0.10-0.15 mm, the drying temperature is 70-120℃, and the drying time is 2-4 min.

[0017] As a further improvement to the above-mentioned solution of the present invention, in step S2, the coating thickness of the water-based intermediate layer slurry is 0.10-0.15 mm, the drying temperature is 70-130°C, and the drying time is 2-4 min.

[0018] As a further improvement to the above-mentioned solution of the present invention, in step S3, the coating thickness of the solvent-free foaming slurry is 0.30-0.40 mm, the drying temperature is 90-130°C, and the drying time is 2-4 min.

[0019] As a further improvement to the above-described scheme of the present invention, in step S4, the curing temperature is preferably 120-140℃, and the curing time is 10-20 minutes. Preferably, the base fabric is a stretch knitted fabric of various spandex or spandex blends, with a thickness ranging from 0.20mm to 0.40mm.

[0020] Compared with the prior art, the present invention has the following beneficial effects:

[0021] 1. This invention adds deionized water to the solvent-free foaming layer and adjusts the amount of catalyst to achieve uniform foaming and a soft feel, thereby developing a solvent-free product similar to traditional wet-process protein leather. It can serve as an environmentally friendly alternative to traditional wet-process protein leather and can be widely used in high-end headphone covers, VR goggles, and other products. Compared with conventional wet-process protein leather technology, the finished product of this invention has superior hydrolysis resistance and physical properties. Its hydrolysis resistance can reach 5 weeks of jungle testing (70℃*95%RH) without cracking or powdering.

[0022] 2. This invention also adds deionized water to the water-based surface layer and water-based intermediate layer. Compared with conventional water-based solvent-free products, it has a softer feel and is more skin-friendly, making it very suitable for processing various electronic wearable devices that come into direct contact with the human body, such as headphones and VR glasses. Detailed Implementation

[0023] To facilitate understanding of the present invention, a more comprehensive description will be given below with reference to specific embodiments. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a more thorough and complete understanding of the disclosure of the present invention.

[0024] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention.

[0025] The specific information of the raw materials used in the following examples and comparative examples is as follows:

[0026] Impranil DLH and Impranil DLU are aliphatic waterborne polyurethane resins manufactured by Covestro Polymers (China) Co., Ltd.

[0027] The black pigment PP-9311, white pigment PP-9338, blue pigment PP-9363, water-based leveling agent LA-91-120, water-based defoamer RM 4456, and silicone additive HM-2186 are all produced by Starr Fine Coatings Co., Ltd.

[0028] The water-based curing agent TD-337B is manufactured by Xiamen Shuozhong Industrial Co., Ltd.

[0029] Polyester-type polyol prepolymer A, AL-2020A, and polyisocyanate prepolymer B, AL-5040B, are produced by Hefei Anli Polyurethane New Materials Co., Ltd.

[0030] Catalyst JF-NS-C310 and foaming agent JF-NS-C221 are both produced by Zhejiang Huafeng New Materials Co., Ltd.

[0031] The lignin was produced by Yixing Shengdeli New Materials Co., Ltd.

[0032] Example 1

[0033] This embodiment proposes an environmentally friendly protein leather synthetic leather for electronic products, the preparation method of which includes the following four steps S1-S4.

[0034] S1. By weight, 100 parts of waterborne polyether polyurethane resin DLH, 40 parts of deionized water, 5 parts of black pigment PP-9311, 0.50 parts of waterborne leveling agent LA-91-120, 0.50 parts of waterborne thickener RM 4456, and 2 parts of organosilicon compound HM-2186 are mixed to prepare a waterborne topcoat slurry. The waterborne topcoat slurry is coated onto release paper with a coating thickness of 0.10 mm and dried and cured at 115°C to form a waterborne topcoat.

[0035] S2. By weight, mix 100 parts of waterborne polyether polyurethane resin DLU, 40 parts of deionized water, 5 parts of black pigment PP-9311, 0.50 parts of waterborne leveling agent LA-91-120, 0.50 parts of waterborne thickener RM 4456, and 1.0 part of waterborne curing agent to prepare an intermediate layer slurry. Coat the intermediate layer slurry onto the waterborne top layer with a coating thickness of 0.10 mm. After drying and curing at 115°C, a waterborne intermediate layer is formed.

[0036] S3. By weight, 100 parts of polyester polyol, 1 part of deionized water, 10 parts of lignin, 0.5 parts of catalyst JF-NS-C310, and 0.5 parts of foaming agent JF-NS-C221 are mixed to prepare material A. Material B is an isocyanate prepolymer. Material A and material B are mixed at a weight ratio of 100:40 to prepare a foaming layer slurry. The foaming layer slurry is coated on the water-based intermediate layer with a coating thickness of 0.30 mm and baked at 90°C to a viscous state to obtain a solvent-free foamed layer.

[0037] S4. The spandex four-elastic base fabric is laminated with a solvent-free foam layer, cured at 120°C, and then cooled and the release paper is peeled off to obtain a dry semi-finished product. After the dry semi-finished product is cured at room temperature for 24 hours, it is treated with a water-based slip agent to produce a skin-friendly and environmentally friendly polyurethane synthetic leather for earphone covers. The texturing process is carried out at an oven temperature of 60°C and a machine speed of 5 meters per minute.

[0038] Example 2

[0039] This embodiment proposes an environmentally friendly protein leather synthetic leather for electronic products, the preparation method of which includes the following four steps S1-S4.

[0040] S1. By weight, 100 parts of waterborne polyether polyurethane resin DLH, 60 parts of deionized water, 12 parts of white pigment PP-9338, 0.90 parts of waterborne leveling agent LA-91-120, 0.80 parts of waterborne thickener RM 4456, and 3 parts of organosilicon compound HM-2186 are mixed to prepare a waterborne topcoat slurry. The waterborne topcoat slurry is coated onto release paper with a coating thickness of 0.12 mm. After drying and curing at 120°C, a waterborne topcoat is formed.

[0041] S2. By weight, mix 100 parts of waterborne polyether polyurethane resin DLU, 60 parts of deionized water, 12 parts of white pigment PP-9338, 0.90 parts of waterborne leveling agent LA-91-120, 0.80 parts of waterborne thickener RM 4456, and 1.5 parts of waterborne curing agent to prepare an intermediate layer slurry. Coat the intermediate layer slurry onto the waterborne top layer with a coating thickness of 0.12 mm. After drying and curing at 120°C, a waterborne intermediate layer is formed.

[0042] S3. By weight, 100 parts of polyester polyol, 1.5 parts of deionized water, 20 parts of lignin, 0.3 parts of catalyst JF-NS-C310, and 1.0 parts of foaming agent JF-NS-C221 are mixed to prepare material A. Material B is an isocyanate prepolymer. Material A and material B are mixed at a weight ratio of 100:45 to prepare a foaming layer slurry. The foaming layer slurry is coated on the water-based intermediate layer with a coating thickness of 0.35 mm and baked at 110°C to a viscous state to obtain a solvent-free foamed layer.

[0043] S4. The spandex four-elastic base fabric is laminated with a solvent-free foam layer, cured at 130°C, and then cooled and the release paper is peeled off to obtain a dry semi-finished product. After curing the dry semi-finished product at room temperature for 48 hours, it is treated with a water-based slip agent to produce a skin-friendly and environmentally friendly polyurethane synthetic leather for earphone covers. The texturing process is carried out at an oven temperature of 70°C and a machine speed of 6 meters per minute.

[0044] Example 3

[0045] This embodiment proposes an environmentally friendly protein leather synthetic leather for electronic products, the preparation method of which includes the following four steps S1-S4.

[0046] S1. By weight, 100 parts of waterborne polyether polyurethane resin DLH, 80 parts of deionized water, 10 parts of blue pigment PP-9363, 1.2 parts of waterborne leveling agent LA-91-120, 1.5 parts of waterborne thickener RM 4456, and 4 parts of organosilicon compound HM-2186 are mixed to prepare a waterborne topcoat slurry. The waterborne topcoat slurry is coated onto release paper with a coating thickness of 0.15 mm and dried and cured at 135°C to form a waterborne topcoat.

[0047] S2. By weight, mix 100 parts of waterborne polyether polyurethane resin DLU, 80 parts of deionized water, 10 parts of blue pigment PP-9363, 1.2 parts of waterborne leveling agent LA-91-120, 1.5 parts of waterborne thickener RM4456, and 2.0 parts of waterborne curing agent to prepare an intermediate layer slurry. Apply the intermediate layer slurry to the waterborne top layer with a coating thickness of 0.15 mm. After drying and curing at 135°C, a waterborne intermediate layer is formed.

[0048] S3. By weight, 100 parts of polyester polyol, 2 parts of deionized water, 20 parts of lignin, 0.1 parts of catalyst JF-NS-C310, and 2.0 parts of foaming agent JF-NS-C221 are mixed to prepare material A. Material B is an isocyanate prepolymer. Material A and material B are mixed at a weight ratio of 100:50 to prepare a foaming layer slurry. The foaming layer slurry is coated on the water-based intermediate layer with a coating thickness of 0.40 mm and baked at 130°C to a viscous state to obtain a solvent-free foamed layer.

[0049] S4. The spandex four-elastic base fabric is laminated with a solvent-free foam layer, cured at 140℃, and then cooled and the release paper is peeled off to obtain a dry semi-finished product. After the dry semi-finished product is cured at room temperature for 48 hours, it is treated with a water-based slip agent to produce a skin-friendly and environmentally friendly polyurethane synthetic leather for earphone covers. The texturing process is carried out at an oven temperature of 8℃ and a machine speed of 7 meters / minute.

[0050] Comparative Example 1

[0051] S1. By weight, mix 100 parts of polyether polyurethane resin DLH, 50 parts of DMF, 10 parts of color powder, and 0.3 parts of leveling agent LA-91-120 to prepare a dry top layer slurry. Then, mix 120 parts of polyether polyurethane resin DLH, 60 parts of DMF, 5 parts of color paste, 10 parts of color powder, and 0.5 parts of leveling agent LA-91-120 to prepare an intermediate layer slurry. Apply the dry top layer slurry to the release paper with a coating thickness of 0.12 mm. After drying and curing at 120°C, a dry top layer is formed. Then, apply the intermediate layer slurry to the dry top layer with a coating thickness of 0.20 mm. After drying and curing at 135°C, an intermediate layer is formed.

[0052] S2. By mass, 100 parts of polyester polyol, 40 parts of kaolin, 0.05 parts of catalyst JF-NS-C310, and 0.05 parts of foaming agent JF-NS-C221 are mixed to prepare material A. Material B is an isocyanate prepolymer. Material A and material B are mixed at a mass ratio of 2:1 to prepare a foaming layer slurry. The foaming layer slurry is coated onto the intermediate layer prepared in step a with a coating thickness of 0.3 mm. After being baked at 100°C to an adhesive state, it is bonded to the spandex four-elastic base fabric. After curing at 130°C, the release paper is peeled off to obtain a dry semi-finished product.

[0053] S3. Depending on the product application requirements, subsequent processing procedures such as texturing, printing, and surface treatment can be carried out.

[0054] Comparative Example 2

[0055] S1. Preparation of wet semi-finished base material: Take 100 parts by weight of PU resin, 20 parts of lignin, 10 parts of calcium carbonate, 80 parts of DMF, 2 parts of color paste, 0.5 parts of penetrant (S-11, Shanghai Risheng Chemical Co., Ltd.) and 0.5 parts of leveling agent (ACR, Yantai Fusong Chemical Co., Ltd.) and mix them to prepare a wet slurry. Coat the wet polyurethane slurry onto spandex four-elastic base fabric with a gap of 1.2 mm. Then place it in an aqueous solution of DMF with a mass fraction of 23% to coagulate. After washing and rolling, dry it with water, dry it at 140℃, cool it and roll it to obtain the wet semi-finished base material.

[0056] S2. Preparation of dry surface layer slurry: Weigh 100 parts LT-8045, 60 parts DMF and 3 parts red paste according to the weight ratio and mix them to prepare the anti-sticking layer slurry. Apply the anti-sticking layer slurry to the release paper with a gap of 0.12mm and dry and cure at 120℃ to obtain the surface layer.

[0057] S3, Adhesive layer coating and bonding: Weigh 100 parts SA-36, 40 parts DMF and 3 parts red paste according to the weight and mix them to prepare an anti-adhesive layer slurry. Apply the anti-adhesive layer slurry to the release paper with a gap of 0.15mm, bake it at 100℃ until semi-dry, and bond it with the wet semi-finished product prepared in S1. Dry, cool and peel it to obtain the dry semi-finished product.

[0058] S4. The dry semi-finished product prepared in S3 is kneaded in a continuous kneading machine for 15 minutes to obtain the wet protein skin finished product.

[0059] Test case

[0060] The physical properties of the protein leather synthetic leather prepared in the above examples and comparative examples were tested, and the test results are shown in Table 1.

[0061] Table 1

[0062] Key Indicators Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 softness and hardness 7.8mm 8.1mm 8.3mm 4.5-6.5mm 7.5-8.5 Peel strength 32 29 28 24-48 12-18 abrasion resistance 800 RPM 800 RPM 500 RPM 500-800 RPM 200-500 RPM Hydrolysis resistance 5 weeks 5 weeks 5 weeks 5 weeks 1-3 weeks DMF content 3ppm 4ppm 2ppm 10-500ppm 500-2000ppm

[0063] The above testing methods or instruments are as follows:

[0064] Hardness / softness: ISO17235-2002;

[0065] Peel strength: GB / T 8949-2008.5.9;

[0066] Abrasion resistance: Table abrasion resistance H-18*500G;

[0067] Hydrolysis resistance: 70℃ * 95% RH;

[0068] DMF content: QB / T5158.

[0069] As can be seen from Table 1, the environmentally friendly protein leather synthetic leather proposed in this invention has a softness and hardness close to that of traditional wet-process protein leather, but its mechanical strength (peel strength, abrasion resistance, etc.) is significantly better than that of traditional wet-process protein leather. In addition, it has excellent hydrolysis resistance and environmental protection performance. It can be used as an environmentally friendly alternative to traditional wet-process protein leather and can be widely used in high-end headphone covers, VR eye masks and other products.

[0070] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the specification of this invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "or / and" as used herein includes any and all combinations of one or more of the associated listed items.

[0071] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0072] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this invention patent should be determined by the appended claims.

Claims

1. An environmentally friendly protein leather synthetic leather for electronic products, characterized in that, It comprises, from top to bottom, an aqueous top layer, an aqueous intermediate layer, a solvent-free foaming layer, and a base fabric layer; the solvent-free foaming layer is prepared from a solvent-free foaming slurry composed of component A and component B, wherein component A is prepared from the following components in parts by weight: 100 parts polyester-type polyol prepolymer, 1-2 parts deionized water, 0-40 parts filler, 0.1-0.5 parts catalyst, and 0.5-2.0 parts foaming agent; component B is an isocyanate prepolymer; The water-based surface layer is prepared from a water-based surface layer slurry, which is prepared from the following components in parts by weight: 100 parts water-based polyurethane, 40-80 parts deionized water, 0.5-1.5 parts water-based thickener, 5-20 parts water-based color paste, 0.5-1.2 parts water-based leveling agent, and 1-2 parts organosilicon. The water-based intermediate layer is prepared from a water-based intermediate layer slurry, which is prepared from the following components in parts by weight: 100 parts water-based polyurethane, 40-80 parts deionized water, 0.5-1.5 parts water-based thickener, 0.5-1.2 parts leveling agent, and 1-2 parts water-based curing agent.

2. The environmentally friendly protein leather synthetic leather for electronic products according to claim 1, characterized in that, In the solvent-free foaming slurry, the mass ratio of component A to component B is 100:40-50.

3. The environmentally friendly protein leather synthetic leather for electronic products according to claim 1, characterized in that, The filler is at least one of ultrafine lignin and ultrafine pulp powder.

4. A method for preparing environmentally friendly protein leather synthetic leather for electronic products as described in any one of claims 1-3, characterized in that, Includes the following steps: S1. Coat the release paper with an aqueous surface layer slurry, and dry it to form an aqueous surface layer; S2. A water-based intermediate layer slurry is coated on the water-based surface layer and dried to form a water-based intermediate layer; S3. A solvent-free foaming slurry is coated onto the aqueous intermediate layer and pre-dried to form a solvent-free foaming layer; S4. The base fabric is bonded to the solvent-free foaming layer, cured, cooled, and the release paper is peeled off to obtain water-based solvent-free polyurethane synthetic leather.

5. The method for preparing environmentally friendly protein leather synthetic leather for electronic products according to claim 4, characterized in that, In step S1, the coating thickness of the water-based surface slurry is 0.10-0.15 mm, the drying temperature is 70-120℃, and the drying time is 2-4 min.

6. The method for preparing environmentally friendly protein leather synthetic leather for electronic products according to claim 4, characterized in that, In step S2, the coating thickness of the water-based intermediate layer slurry is 0.10-0.15 mm, the drying temperature is 70-130℃, and the drying time is 2-4 min.

7. The method for preparing environmentally friendly protein leather synthetic leather for electronic products according to claim 4, characterized in that, In step S3, the coating thickness of the solvent-free foaming slurry is 0.30-0.40 mm, the drying temperature is 90-130℃, and the drying time is 2-4 min.

8. The method for preparing environmentally friendly protein leather synthetic leather for electronic products according to claim 4, characterized in that, In step S4, the curing temperature is 120-140℃ and the curing time is 10-20min.