Preparation method of brilliant-texture metal wiredrawing PU (polyurethane) synthetic leather

Abstract

The invention discloses a preparation method of brilliant-texture metal wiredrawing PU synthetic leather. The preparation method comprises the following steps: S1, preparing release paper with metal wiredrawing texture; s2, release paper is coated with surface layer coating liquid to obtain a surface layer, the surface layer coating liquid is prepared from, by weight, 50.5%-69.1% of polyurethane, 9.9%-16.5% of pigment, 4.0%-8.0% of pearl powder and 26%-28% of dissolving medium, and the particle size of the pearl powder is 5-50 microns; s3, coating foaming coating liquid to obtain a foaming layer; s4, the first composite layer and the base cloth are attached, dried and cured, and a second composite layer is obtained; s5, stripping the release paper to obtain a third composite layer; s6, performing surface treatment on the surface layer to obtain a PU synthetic leather finished product. By optimizing the materials of the surface layer and the surface treatment layer, the color concentration degree of the product is better, and the cracking strength and the tensile strength are improved; and by adopting the wiredrawing texture release paper, the product has a metal wiredrawing feeling, and the appearance texture is improved.

Description

Technical Field

[0001] The invention belongs to the technical field of artificial leather, and in particular relates to a method for preparing brilliant textured metal brushed PU synthetic leather. Background Art

[0002] Artificial leather is an imitation of natural leather. With the development of artificial technology, it has been used to replace natural leather in most areas of life due to its various performance and material characteristics of natural leather. It is currently widely used in decoration of luggage, clothing, shoes, vehicles and furniture.

[0003] Pearlescent leather made of pearlescent pigments has been widely used in various high-end cars, railway coaches, airplanes, passenger ropeway carriages, and sofas in recent years. It is both beautiful and practical, and has become the most popular new variety of artificial leather. The durability of modified artificial leather resin has greatly exceeded that of most animal leathers, and it is more environmentally friendly and safer. There are many ways to apply pearlescent pigments to artificial leather. Currently, the main methods are printing and coating. The printing process is relatively simple, while the coating method is more difficult.

[0004] The biggest quality problem of pearlescent leather products on the market is that the vividness of the surface color is not good and the visual effect is not good. Therefore, the present invention is based on this. Summary of the invention

[0005] In view of one of the above-mentioned technical problems, the object of the present invention is to provide a method for preparing a shiny textured metal brushed PU synthetic leather.

[0006] The technical solution of the present invention is:

[0007] The object of the present invention is to provide a method for preparing a PU synthetic leather with a brilliant texture and metal brushing, wherein the PU synthetic leather comprises a base fabric layer, a foaming layer, a surface layer and a surface treatment layer which are stacked in sequence, and the preparation method comprises the following steps:

[0008] S1. Prepare release paper with a brushed metal texture;

[0009] S2, coating a surface coating liquid on the drawing side of the release paper in step S1, heating and removing the solvent in the surface coating liquid to obtain a surface layer, wherein the surface coating liquid comprises the following components in weight percentage: 50.5% to 69.1% polyurethane, 9.9% to 16.5% pigment, 4.0% to 8.0% pearl powder, and 26% to 28% dissolving medium, wherein the particle size of the pearl powder is between 5 and 50 μm;

[0010] S3, coating the surface of the surface layer obtained in step S2 on the side facing away from the release paper with a foaming coating liquid, and heating to obtain an incompletely cured foaming layer;

[0011] S4, laminating the first composite layer including the release paper, the surface layer and the foaming layer obtained in step S3 to the base fabric, and drying and curing them to obtain a second composite layer including the release paper, the surface layer, the foaming layer and the base fabric layer;

[0012] S5, peeling off the release paper and other structural layers in the second composite layer in step S4 to obtain a third composite layer including only the surface layer, the foaming layer and the base fabric layer;

[0013] S6. Surface-treating the surface layer of the third composite layer in step S5 to obtain a PU synthetic leather product including the third composite layer and a surface-treated layer.

[0014] Preferably, in step S1, the wire drawing of the release paper is arranged longitudinally, the surface of the release paper is rough and the surface is PP or leather transfer paper coated with silicone oil.

[0015] Preferably, in step S2, the dissolving medium is a solvent formed by mixing butanone and N,N-dimethylformamide in a weight ratio of 1:1.

[0016] Preferably, in step S3, the foaming coating liquid includes the following components in weight percentage: polyurethane 25.7% to 27.7%, hardener 54.7% to 56.7%, catalyst 0.04% to 1.04%, solvent 3.4% to 5.4%, flame retardant 10.6% to 12.6%, and pigment 0.6% to 2.6%.

[0017] Preferably, the hardener is a yellowing-resistant hardener, the catalyst is a catalyst formed by an amine-based organic acid salt, the solvent is butanone and its polycondensate, and the flame retardant is a phosphorus-based flame retardant.

[0018] Preferably, in step S6, the surface treatment is carried out by coating with a surface treatment agent, and the surface treatment agent includes the following components in weight percentage: 40% to 80% polyurethane, 1% to 5% cross-linking agent, 0.5% to 3.5% tackifier, 5% to 15% hand feeling agent, and 10% to 50% water.

[0019] Preferably, the cross-linking agent is a multifunctional carbodiimide polymer, the tackifier is an alkaline tackifier, and the feel agent is a silicon-based agent and a silicon polymer thereof.

[0020] Preferably, in step S4, the base fabric layer has a thickness of 800 to 1000 μm and a weight of 250 to 380 g / cm 2 Circular knitted fabric, warp knitted fabric, woven fabric or non-woven fabric.

[0021] Compared with the prior art, the advantages of the present invention are:

[0022] The present invention optimizes the surface material and adds an appropriate amount of bright powder to make the product have a bright texture; optimizes the material components of the surface treatment layer to make the product color concentration better, and at the same time improves the physical properties of the product. The cracking and tensile strengths are improved; in addition, the brushed texture release paper is used to make the final product have a metallic brushed feel, thereby improving the appearance texture of the product, improving the design sense of the product, and broadening the product types of the enterprise. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The present invention will be further described below in conjunction with the accompanying drawings and embodiments:

[0024] Figure 1 This is a photo of one of the shiny textured metal brushed PU synthetic leathers prepared by the preparation method of Example 1 of the present invention;

[0025] Figure 2 This is a photo of another type of shiny textured metal brushed PU synthetic leather prepared by the preparation method of Example 1 of the present invention. DETAILED DESCRIPTION

[0026] In order to make the purpose, technical scheme and advantages of the present invention clearer, the present invention is further described in detail below in conjunction with specific embodiments and with reference to the accompanying drawings. It should be understood that these descriptions are only exemplary and are not intended to limit the scope of the present invention. In addition, in the following description, the description of well-known structures and technologies is omitted to avoid unnecessary confusion of the concept of the present invention.

[0027] The method for preparing the glossy textured metal brushed PU synthetic leather of the embodiment of the present invention, wherein the PU synthetic leather is as follows Figure 1 The method includes a base fabric layer, a foaming layer, a surface layer and a surface treatment layer stacked in sequence from bottom to top. Specifically, the preparation method includes the following steps:

[0028] S1. Prepare release paper with a brushed metal texture;

[0029] S2, coating a surface coating liquid on the drawing side of the release paper in step S1, heating and removing the solvent in the surface coating liquid to obtain a surface layer, wherein the surface coating liquid comprises the following components in weight percentage: 50.5% to 69.1% polyurethane, 9.9% to 16.5% pigment, 4.0% to 8.0% pearl powder, and 26% to 28% dissolving medium, wherein the particle size of the pearl powder is between 5 and 50 μm;

[0030] S3, coating the surface of the surface layer obtained in step S2 on the side facing away from the release paper with a foaming coating liquid, and heating to obtain an incompletely cured foaming layer;

[0031] S4, laminating the first composite layer including the release paper, the surface layer and the foaming layer obtained in step S3 to the base fabric, and drying and curing them to obtain a second composite layer including the release paper, the surface layer, the foaming layer and the base fabric layer;

[0032] S5, peeling off the release paper and other structural layers in the second composite layer in step S4 to obtain a third composite layer including only the surface layer, the foaming layer and the base fabric layer;

[0033] S6. Surface-treating the surface layer of the third composite layer in step S5 to obtain a PU synthetic leather product including the third composite layer and a surface-treated layer.

[0034] According to some preferred embodiments of the present invention, in step S1, the wire drawing of the release paper is arranged longitudinally, the surface of the release paper is rough and the surface is PP or leather transfer paper coated with silicone oil.

[0035] According to some preferred embodiments of the present invention, in step S2, the dissolving medium is a solvent formed by mixing butanone (MEK) and N,N-dimethylformamide (DMF) in a weight ratio of 1: 1. By rationally optimizing the ratio of the dissolving medium, the components of the surface coating liquid can better react with each other, which is beneficial to improving the product's cracking and tensile strength properties.

[0036] According to some preferred embodiments of the present invention, in step S3, the foaming coating liquid includes the following components in weight percentage: polyurethane 25.7% to 27.7%, hardener 54.7% to 56.7%, catalyst 0.04% to 1.04%, solvent 3.4% to 5.4%, flame retardant 10.6% to 12.6%, pigment 0.6% to 2.6%. During use, the raw materials of each component need to be stirred for more than 30 minutes so that the surface treatment agent coating can be integrated on the surface layer to improve the bonding degree between the two. Further preferably, the hardener of the embodiment of the present invention is a conventional yellowing-resistant hardener currently available on the market, the catalyst is a catalyst formed by conventional amine-based organic acid salts currently available on the market, the solvent is butanone and its polycondensate, and the flame retardant is a conventional phosphorus-based flame retardant currently available on the market. By optimizing the formula of each component of the foaming coating liquid, the foaming layer has better adhesion and foaming properties. The addition of anti-yellowing hardener can increase the service life of the foaming layer. The use of catalysts formed by amine organic acid salts is conducive to better bonding between the components and the combination of the foaming coating liquid with the surface layer and the surface treatment layer.

[0037] It should be noted that the pigments in the foaming coating liquid and the surface coating liquid are conventional leather pigments currently available on the market. Of course, pigments with different functions can also be selected according to the functionality of the leather, such as infrared reflective pigments.

[0038] According to some preferred embodiments of the present invention, in step S6, the surface treatment is applied with a surface treatment agent, and the surface treatment agent includes the following components in weight percentage: 40% to 80% polyurethane, 1% to 5% cross-linking agent, 0.5% to 3.5% tackifier, 5% to 15% hand feeling agent, and 10% to 50% water. Further preferably, the cross-linking agent of the embodiment of the present invention is a conventional multifunctional carbodiimide polymer on the market, the tackifier is a conventional alkaline tackifier on the market, and the hand feeling agent is a conventional silicon system and its silicon polymer for leather on the market. By optimizing the components of the surface treatment agent, the wear resistance of the surface treatment layer and the bonding performance with the surface layer are improved, which is beneficial to improving the overall cracking and tensile strength properties of the product.

[0039] According to some preferred embodiments of the present invention, in step S4, the base fabric layer has a thickness of 800-1000 μm and a weight of 250-380 g / cm 2 Circular knitted fabric, warp knitted fabric, woven fabric or non-woven fabric.

[0040] The embodiment of the present invention optimizes the surface material and adds an appropriate amount of bright powder to make the product have a bright texture; optimizes the material components of the surface treatment layer to make the product color concentration better, and at the same time improves the physical properties of the product. The cracking and tensile strength are improved; in addition, the brushed texture release paper is used to make the final product have a metallic brushed feel, thereby improving the appearance texture of the product, improving the design sense of the product, and broadening the company's product types.

[0041] More specific embodiments are as follows:

[0042] Example 1

[0043] The method for preparing the brilliant textured metal brushed PU synthetic leather of this embodiment comprises the following steps:

[0044] S1. Prepare a release paper with a brushed metal texture, wherein the brushed metal of the release paper is arranged vertically, and the surface of the release paper is rough and is made of PP or a transfer paper for leather coated with silicone oil;

[0045] S2, coating a surface coating liquid on the drawing side of the release paper in step S1, heating and removing the solvent in the surface coating liquid to obtain a surface layer, wherein the surface coating liquid comprises the following components in weight percentage: 60% polyurethane, 12% pigment, 6.0% pearl powder, and 26% dissolving medium, wherein the particle size of the pearl powder is between 5-50 μm, and the dissolving medium is a solvent formed by mixing butanone and N,N-dimethylformamide in a weight ratio of 1:1;

[0046] S3, coating a foaming coating liquid on the side of the surface layer obtained in step S2 that is away from the release paper, and heating to obtain an incompletely cured foaming layer, wherein the foaming coating liquid comprises the following components in percentage by weight: 26.7% polyurethane, 55.7% hardener, 0.54% catalyst, 4.4% solvent, 11.6% flame retardant, and 1.6% pigment, wherein the hardener is a yellowing-resistant hardener, the catalyst is a catalyst formed by an amine-based organic acid salt, the solvent is butanone and its polycondensate, and the flame retardant is a phosphorus-based flame retardant;

[0047] S4, the first composite layer including the release paper, the surface layer and the foaming layer obtained in step S3 is laminated to the base fabric, and dried and cured to obtain a second composite layer including the release paper, the surface layer, the foaming layer and the base fabric layer, the surface treatment agent includes the following components in weight percentage: 60% polyurethane, 3% cross-linking agent, 2% tackifier, 10% hand feeling agent, 30% water, the cross-linking agent is a multifunctional carbodiimide polymer, the tackifier is an alkaline tackifier, the hand feeling agent is a silicon system and its silicon polymer, the base fabric layer is 800-1000 μm thick and 250-380 g / cm 2 circular knitted fabric, warp knitted fabric, woven fabric or non-woven fabric;

[0048] S5, peeling the release paper and other structural layers in the second composite layer in step S4 using a conventional peeling device in the existing synthetic leather production process to obtain a third composite layer including only the surface layer, the foaming layer and the base fabric layer;

[0049] S6. Surface-treating the surface layer of the third composite layer in step S5 to obtain a PU synthetic leather product including the third composite layer and a surface-treated layer.

[0050] Example 2

[0051] The difference from Example 1 is that the weight percentage of pearlescent powder in the components of the surface coating liquid in this example is different, and the other components and parameters of each step are the same. Specifically, the weight percentage of pearlescent powder in this example is 3.5%.

[0052] Example 3

[0053] The difference between the embodiment 1 and the embodiment 2 is that the weight percentage of the pearlescent powder in the components of the surface coating liquid in this embodiment is different, and the other components and parameters of each step are the same. Specifically, the weight percentage of the pearlescent powder in this embodiment is 10%.

[0054] After testing, it should be noted that the testing in the embodiments of the present invention is based on the existing national standard, industry standard or enterprise standard, and the specific testing method is not described or limited. After testing, the color of the surface layer of the PU synthetic leather of Example 1 is good in color concentration, the visual effect meets customer requirements and has a pearlescent feel, while the color of the surface layer of the PU synthetic leather of Example 2 is gray, the visual effect is poor and there is no pearlescent feel, and the color of the surface layer of the PU synthetic leather of Example 3 is bright, but the visual effect is too bright and the pearlescent feel is too strong.

[0055] Table 1 Performance test table of PU synthetic leather of Example 1

[0056]

[0057] Note: All performance tests in Table 1 are carried out with reference to relevant national standards, industry standards or enterprise standards for artificial leather. The specific test methods are not described or limited.

[0058] It can be seen from Table 1 that the PU synthetic leather prepared by the preparation method of the embodiment of the present invention has improved properties in terms of cracking and tensile strength compared with the existing common PU synthetic leather.

[0059] like Figure 1 and Figure 2 As shown, the finished product of PU synthetic leather prepared by the preparation method of an embodiment of the present invention is taken under normal light source. The release paper and pigment used in the two are different, and the colors and leather texture effects presented are different. It can be seen that the PU synthetic leather prepared by the preparation method of an embodiment of the present invention has better color and visual effect, and has a pearlescent effect.

[0060] The specified directions in this specific embodiment are only for the convenience of describing the positional relationship and the coordination relationship between the components. The above is only a preferred embodiment of the present invention. The protection scope of the present invention is not limited to the above embodiment. All technical solutions under the concept of the present invention belong to the protection scope of the present invention. It should be pointed out that for ordinary technicians in this technical field, some improvements and modifications without departing from the principle of the present invention should also be regarded as the protection scope of the present invention.

Claims

1. A method for preparing a shiny textured metal brushed PU synthetic leather, characterized in that: The PU synthetic leather comprises a base fabric layer, a foaming layer, a surface layer and a surface treatment layer stacked in sequence, and the preparation method comprises the following steps: S1. Prepare release paper with a brushed metal texture; S2, coating a surface coating liquid on one side of the release paper of step S1, heating and removing the solvent in the surface coating liquid to obtain a surface layer, wherein the surface coating liquid comprises the following components in weight percentage: 50.5% to 69.1% polyurethane, 9.9% to 16.5% pigment, 4.0% to 8.0% pearl powder, and 26% to 28% dissolving medium, wherein the particle size of the pearl powder is between 5 and 50 μm; S3, coating the surface of the surface layer obtained in step S2 on the side facing away from the release paper with a foaming coating liquid, and heating to obtain an incompletely cured foaming layer; S4, laminating the first composite layer including the release paper, the surface layer and the foaming layer obtained in step S3 to the base fabric, and drying and curing them to obtain a second composite layer including the release paper, the surface layer, the foaming layer and the base fabric layer; S5, peeling off the release paper and other structural layers in the second composite layer in step S4 to obtain a third composite layer including only the surface layer, the foaming layer and the base fabric layer; S6. Surface-treating the surface layer of the third composite layer in step S5 to obtain a PU synthetic leather product including the third composite layer and a surface-treated layer.

2. The preparation method according to claim 1, characterized in that: In step S1, the wire drawing of the release paper is arranged longitudinally, the surface of the release paper is rough and the surface is PP or leather transfer paper coated with silicone oil.

3. The preparation method according to claim 1, characterized in that: In step S2, the dissolving medium is a solvent formed by mixing butanone and N,N-dimethylformamide in a weight ratio of 1:

1.

4. The preparation method according to claim 1, characterized in that: In step S3, the foaming coating liquid includes the following components in weight percentage: polyurethane 25.7% to 27.7%, hardener 54.7% to 56.7%, catalyst 0.04% to 1.04%, solvent 3.4% to 5.4%, flame retardant 10.6% to 12.6%, and pigment 0.6% to 2.6%.

5. The preparation method according to claim 4, characterized in that: The hardener is a yellowing-resistant hardener, the catalyst is a catalyst formed by an amine-based organic acid salt, the solvent is butanone and its polycondensate, and the flame retardant is a phosphorus-based flame retardant.

6. The preparation method according to claim 1, characterized in that: In step S6, the surface treatment is performed by coating with a surface treatment agent, wherein the surface treatment agent includes the following components in weight percentage: 40% to 80% polyurethane, 1% to 5% cross-linking agent, 0.5% to 3.5% tackifier, 5% to 15% hand feeling agent, and 10% to 50% water.

7. The preparation method according to claim 6, characterized in that: The cross-linking agent is a multifunctional carbodiimide polymer, the tackifier is an alkaline tackifier, and the hand feeling agent is a silicon-based agent and a silicon polymer thereof.

8. The preparation method according to claim 1, characterized in that: In step S4, the base fabric layer has a thickness of 800-1000 μm and a weight of 250-380 g / cm 2 Circular knitted fabric, warp knitted fabric, woven fabric or non-woven fabric.

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