A preparation method of high moisture absorption and breathable lining leather

Abstract

The invention relates to the technical field of lining leather preparation, and particularly to a method for preparing highly hygroscopic and breathable lining leather. The method comprises the following steps: firstly, a high-modulus, low-solidity, ultra-large-cell process is adopted in a wet slurry; and then the process comprises weight reduction, dyeing, a bass hydrophilic softening treatment, three-plate special skin-feel treatment, mirror roller ironing, three-plate re-treatment, and rubbing to obtain the highly hygroscopic and breathable lining leather. The preparation method is simple and easy to operate. The prepared microfiber lining leather has excellent hygroscopicity, and a drop of water can completely penetrate the leather within 1-2 seconds. After absorbing water, the leather surface is flat and does not swell or bubble. The leather has good air permeability, a variety of colors, and a genuine leather texture. The leather has good softness and good market prospects.

Description

Technical Field

[0001] The invention relates to the technical field of lining leather preparation, and in particular to a method for preparing highly moisture-absorbent and breathable lining leather. Background Art

[0002] Artificial leather is a plastic product that looks and feels like leather and can be used as a substitute. It is typically made from a fabric base coated with synthetic resin and various plastic additives. There are three main types of artificial leather: PVC, PU, and PU synthetic leather.

[0003] At present, the existing lining leather has low moisture absorption, the leather surface is uneven after absorbing water, and it is easy to swell and bubble, and the air permeability and softness are poor, and the user experience is poor. Therefore, a preparation method of highly moisture-absorbing and breathable lining leather is needed. Summary of the Invention

[0004] In response to the above-mentioned shortcomings in the prior art, the present invention provides a method for preparing highly moisture-absorbent and breathable lining leather, which is used to solve the problems of low moisture absorption of the existing lining leather, uneven leather surface after water absorption, easy swelling and bubbling, poor air permeability and softness, and poor user experience.

[0005] In order to solve the above technical problems, the present invention adopts the following technical solutions:

[0006] A method for preparing a highly moisture-absorbent and breathable lining leather comprises the following steps:

[0007] (1) Preparation of ultrafine denier sea-island fibers and non-woven fabrics: Polyamide 6 and low-density polyethylene are used as raw materials to prepare ultrafine denier indefinite island-island staple fibers of equal length. The prepared ultrafine denier indefinite island-island staple fibers are opened and carded into a web, and then repeatedly punctured up and down with high needle density to prepare a non-woven fabric; after being rolled, they are heat-shrinkaged and shaped to obtain a high-density ironed non-woven fabric;

[0008] (2) Wet impregnation: the non-woven fabric obtained in step (1) is impregnated with a polyether polyurethane circulatory stirring solution, the impregnation solution is squeezed with a roller, and the impregnation solution on both sides of the non-woven fabric is scraped clean with a scraper, and then solidified and foamed with a dimethylformamide aqueous solution with a mass concentration of 10-15%, and then washed with water to remove the residual dimethylformamide on the non-woven fabric, thereby obtaining a wet-process base of a polyurethane non-woven fabric for lining leather;

[0009] (3) Toluene reduction and oiling and drying after finishing: the inner leather polyurethane non-woven fabric wet base obtained in step (2) is subjected to toluene reduction and residual toluene is removed by high-temperature water, and then the base is overfed, relaxed, dried, hydrophilized and stretched in a widening dryer, the drying temperature is 100-120°C, the base width is 1.4-1.5m, the working liquid hydrophilic agent ratio is: modified silane: water = 2-5:95-98, and then kneaded, the kneading amplitude is 5-10cm, the kneading frequency is 280-400, the kneading gap is 1-3cm, and the kneading speed is 3-6m / min to obtain a highly hygroscopic and breathable inner leather base;

[0010] (4) Three-plate post-processing and embossing process: The high moisture absorption and breathable inner leather obtained in step (3) is subjected to sheet grinding, three-plate pre-processing, mirror roller embossing, three-plate re-processing of color and light haze, and rubbing, wherein the leather is ground using sandpaper with a mesh number of 240 mesh + 400 mesh, a rotation speed of 1000-1500r / min, the three-plate pre-processing uses a matte skin-feeling treatment material, the treatment roller mesh number is 120-200 mesh, the mirror roller embossing process temperature is 180-250℃, the speed is 3-6m / min, the gap is 30-60 silk, the three-plate re-processing bright surface + matte feel agent, the treatment roller is a 200-240 mesh anilox roller, and the rubbing adopts a roller-type cold air rubbing to obtain a high moisture absorption and breathable inner finished leather.

[0011] Furthermore, in step (1), the temperature for heat shrinkage setting is 90-140°C, the vehicle speed is 3-6 m / min, the density of the set non-woven fabric is 0.32-0.35 g / m2, and the ratio of the gap between the setting rollers to the thickness of the non-woven fabric is 1.1-1.5.

[0012] Furthermore, the modulus of the impregnation liquid in step (2) is 90-120 kg / cm2, the solid content is 8-12%, and the impregnation liquid preparation ratio is: polyether polyurethane slurry: DMF: cell regulator: penetrant: DMF removal auxiliary agent: protein agent = 100:300-400:0.5-2:0.5-2:0.2-1:5-10.

[0013] Furthermore, the concentration of the hydrophilic agent in the working solution in step (3) is 1-3%.

[0014] Furthermore, the kneading time in step (4) is 30-60 minutes.

[0015] Furthermore, the graining in step (4) can be performed by dry graining or water graining. If the pattern is required to be finer, dry graining is used, the temperature is 30-80°C, and the speed is 6-10m / min. If the pattern is required to be coarser, water graining is used, the water graining temperature is 30-50°C, and the drying temperature is 60-100°C. DETAILED DESCRIPTION

[0016] In order to enable those skilled in the art to better understand the present invention, the technical solution of the present invention is further described below with reference to embodiments.

[0017] Example:

[0018] A method for preparing a highly moisture-absorbent and breathable lining leather of the present invention comprises the following steps:

[0019] (1) Preparation of ultrafine denier sea-island fibers and non-woven fabrics: Polyamide 6 and low-density polyethylene are used as raw materials to prepare ultrafine denier indefinite island-island staple fibers of equal length. The prepared ultrafine denier indefinite island-island staple fibers are opened and carded into a web, and then repeatedly punctured up and down with high needle density to prepare a non-woven fabric; after being rolled, they are heat-shrinkaged and shaped to obtain a high-density ironed non-woven fabric;

[0020] (2) Wet impregnation: the non-woven fabric obtained in step (1) is impregnated with a polyether polyurethane circulatory stirring solution, the impregnation solution is squeezed with a roller, and the impregnation solution on both sides of the non-woven fabric is scraped clean with a scraper, and then solidified and foamed with a dimethylformamide aqueous solution with a mass concentration of 10-15%, and then washed with water to remove the residual dimethylformamide on the non-woven fabric, thereby obtaining a wet-process base of a polyurethane non-woven fabric for lining leather;

[0021] (3) Toluene reduction and oiling and drying after finishing: the inner leather polyurethane non-woven fabric wet base obtained in step (2) is subjected to toluene reduction and residual toluene is removed by high-temperature water, and then the base is overfed, relaxed, dried, hydrophilized and stretched in a widening dryer, the drying temperature is 100-120°C, the base width is 1.4-1.5m, the working liquid hydrophilic agent ratio is: modified silane: water = 2-5:95-98, and then kneaded, the kneading amplitude is 5-10cm, the kneading frequency is 280-400, the kneading gap is 1-3cm, and the kneading speed is 3-6m / min to obtain a highly hygroscopic and breathable inner leather base;

[0022] (4) Three-plate post-processing and embossing process: The high moisture absorption and breathable inner leather obtained in step (3) is subjected to sheet grinding, three-plate pre-processing, mirror roller embossing, three-plate re-processing of color and light haze, and rubbing, wherein the leather is ground using sandpaper with a mesh number of 240 mesh + 400 mesh, a rotation speed of 1000-1500r / min, the three-plate pre-processing uses a matte skin-feeling treatment material, the treatment roller mesh number is 120-200 mesh, the mirror roller embossing process temperature is 180-250℃, the speed is 3-6m / min, the gap is 30-60 silk, the three-plate re-processing bright surface + matte feel agent, the treatment roller is a 200-240 mesh anilox roller, and the rubbing adopts a roller-type cold air rubbing to obtain a high moisture absorption and breathable inner finished leather.

[0023] In step (1), the temperature for heat shrinkage setting is 90-140° C., the vehicle speed is 3-6 m / min, the density of the set non-woven fabric is 0.32-0.35 g / m2, and the ratio of the gap between the setting rollers to the thickness of the non-woven fabric is 1.1-1.5.

[0024] The modulus of the impregnation liquid in step (2) is 90-120 kg / cm2, the solid content is 8-12%, and the impregnation liquid preparation ratio is: polyether polyurethane slurry: DMF: cell regulator: penetrant: DMF removal auxiliary agent: protein agent = 100:300-400:0.5-2:0.5-2:0.2-1:5-10.

[0025] The concentration of the hydrophilic agent in the working solution in step (3) is 1-3%.

[0026] The kneading time in step (4) is 30-60 minutes.

[0027] The rubbing in step (4) can be done by dry rubbing or water rubbing. If the pattern is required to be finer, dry rubbing is used, the temperature is 30-80°C, and the speed is 6-10m / min. If the pattern is required to be coarser, water rubbing is used, the water rubbing temperature is 30-50°C, and the drying temperature is 60-100°C.

[0028] Comparative Example 1:

[0029] The same as Example 1, the only difference is that the temperature of heat shrinkage setting in step (1) is 70°C, and the finished product obtained cannot be fixed, and the hardness and flatness are insufficient.

[0030] Comparative Example 2:

[0031] The same as Example 1, the only difference is that the temperature of heat shrinkage setting in step (1) is 160°C, and the LDPE in the finished product will be completely melted, destroying the fiber structure of the base fabric, affecting the flatness, longitudinal and transverse elongation and yellowing of the base fabric.

[0032] Comparative Example 3:

[0033] The same as Example 1, the only difference is that the concentration of the hydrophilic agent in the working solution in step (3) is 0.5%, and the water absorption performance of the finished product is not up to standard, and the water absorption is too slow to reach 2-3 seconds for complete penetration and absorption.

[0034] Comparative Example 4:

[0035] The same as Example 1, the only difference is that the concentration of the hydrophilic agent in the working solution in step (3) is 5%, the cost of the finished product is high, the hydrolysis and peeling resistance is low, and the color fastness is low.

[0036] Comparative Example 5:

[0037] The same as Example 1, the only difference is that the rubbing time in step (4) is 20 minutes, the texture of the finished product is uneven, and the leather texture effect is not achieved.

[0038] Comparative Example 6:

[0039] The same as Example 1, the only difference is that the rubbing time in step (4) is 80 minutes. The texture of the finished product is too rough, the feel is too hard, and the width is narrow, which does not meet customer requirements.

[0040] By comparing the examples and comparative examples 1-6, it can be seen that:

[0041] 1. The microfiber lining leather prepared by the present invention has good hygroscopicity. A drop of water can penetrate completely in 1-2 seconds. After absorbing water, the leather surface is flat and does not swell or bubble.

[0042] 2. The microfiber lining leather prepared by the present invention has good air permeability, is supplemented by genuine leather texture, has good softness, and has good market prospects.

[0043] The above are only embodiments of the present invention. Common knowledge such as the known specific structures and characteristics in the scheme is not described in detail here. Ordinary technicians in the relevant field are aware of all common technical knowledge in the technical field of the invention before the application date or priority date, can obtain all existing technologies in the field, and have the ability to apply conventional experimental means before that date. Ordinary technicians in the relevant field can improve and implement this scheme in combination with their own abilities under the guidance of this application. Some typical known structures or known methods should not become obstacles for ordinary technicians in the relevant field to implement this application. It should be pointed out that for those skilled in the art, without departing from the structure of the present invention, several variations and improvements can be made, which should also be regarded as the scope of protection of the present invention. These will not affect the effect of the implementation of the present invention and the practicality of the patent.

Claims

1. A method for preparing a highly moisture-absorbent and breathable lining leather, characterized in that: The steps include: (1) Preparation of ultrafine denier sea-island fibers and non-woven fabrics: Polyamide 6 and low-density polyethylene are used as raw materials to make ultrafine denier indefinite island-island staple fibers of equal length. The prepared ultrafine denier indefinite island-island staple fibers are opened and carded into a web, and then repeatedly punctured up and down with high needle density to produce non-woven fabrics; after being rolled, they are heat-shrinkaged and shaped to obtain high-density ironed non-woven fabrics; (2) Wet impregnation: The non-woven fabric obtained in step (1) is impregnated with a polyether polyurethane circulating stirring solution, the impregnation solution is squeezed with a roller, and the impregnation solution on both sides of the non-woven fabric is scraped clean with a scraper, and then solidified and foamed with a dimethylformamide aqueous solution with a mass concentration of 10-15%, and then washed with water to remove the residual dimethylformamide on the non-woven fabric to obtain a wet-process base of a lining leather polyurethane non-woven fabric; (3) Toluene reduction and oiling and drying after finishing: the inner leather polyurethane non-woven fabric wet base obtained in step (2) is subjected to toluene reduction and the residual toluene is removed by high-temperature water, and then the base is overfed, relaxed, dried and hydrophilized in a widening dryer, and stretched. The drying temperature is 100-120°C, the base width is 1.4-1.5m, the working liquid hydrophilic agent ratio is: modified silane: water = 2-5:95-98, and then kneaded, the kneading amplitude is 5-10cm, the kneading frequency is 280-400, the kneading gap is 1-3cm, and the kneading speed is 3-6m / min to obtain a highly moisture-absorbent and breathable inner leather base; (4) Three-plate post-processing and embossing process: the high moisture absorption and breathable inner leather obtained in step (3) is subjected to sheet grinding, three-plate pre-processing, mirror roller embossing, three-plate re-processing for color and light haze, and rubbing, wherein the sandpaper with a mesh number of 240 mesh + 400 mesh is used for the grinding, the speed is 1000-1500r / min, the three-plate pre-processing adopts a matte skin-feeling treatment material, the treatment roller mesh number is 120-200 mesh, the mirror roller embossing process temperature is 180-250℃, the speed is 3-6m / min, the gap is 30-60 wires, the three-plate re-processing bright surface + matte feel agent, the treatment roller is a 200-240 mesh anilox roller, and the rubbing adopts a roller-type cold air rubbing to obtain a high moisture absorption and breathable inner finished leather; The modulus of the impregnation liquid in step (2) is 90-120 kg / cm2, the solid content is 8-12%, and the impregnation liquid is prepared in the following proportions: polyether polyurethane slurry: DMF: cell regulator: penetrant: DMF removal aid: protein agent = 100:300-400:0.5-2:0.5-2:0.2-1:5-10; The concentration of the hydrophilic agent in the working solution in step (3) is 1-3%; The kneading time in step (4) is 30-60 minutes. The kneading in step (4) can be carried out by dry kneading and water kneading. If the pattern is required to be finer, dry kneading is used, the temperature is 30-80°C, and the speed is 6-10m / min. If the pattern is required to be coarser, water kneading is used, the water kneading temperature is 30-50°C, and the drying temperature is 60-100°C.

2. The method for preparing a highly moisture-absorbent and breathable lining leather according to claim 1, wherein: In the step (1), the temperature for heat shrinkage setting is 90-140°C, the vehicle speed is 3-6 m / min, the density of the set non-woven fabric is 0.32-0.35 g / m2, and the ratio of the gap between the setting rollers to the thickness of the non-woven fabric is 1.1-1.5.