KR100804042B1 - Artificial leather with excellent abrasion property and method of manufacturing the same - Google Patents

Abstract

The present invention relates to an artificial leather excellent in wear strength and a method of manufacturing the same, characterized in that the silicone rubber is coated (coated) on the surface of a conventional artificial leather.

The present invention is manufactured by coating (coating) a silicone rubber composition on a surface of a conventional artificial leather and curing the silicone rubber, which is present only on the surface without impregnation to the inside, thereby improving wear resistance without deterioration in elasticity.

Artificial leather, wear strength, elasticity, silicone rubber, coating, coating.

Description

Artificial leather with excellent abrasion strength and its manufacturing method {Artificial leather with excellent abrasion property and method of manufacturing the same}

1 is a schematic cross-sectional view of an artificial leather according to the present invention.

* Explanation of symbols on the main parts of the drawings

1: artificial leather material 2: hair

3: silicone coating

The present invention relates to an artificial leather having excellent wear strength and a method of manufacturing the same, and more particularly, to a suede effect that expresses the feel and appearance as a natural leather, and an artificial leather having excellent elasticity and wear strength at the same time and its manufacture. It is about a method.

As is well known, leather sheets manufactured through a series of processes such as filling a microporous polyurethane elastomer with a wet processing method in a microfiber composite fiber non-woven fabric that can be microfiberized by a microfabrication process are a basic material of artificial leather. It has been widely used.

Looking at the manufacturing method of artificial leather which is a leather-like sheet consisting of a conventional microfiber nonwoven fabric of less than 0.3 denier and a polyurethane elastomer as follows.

2 to 5 denier composite fibers which can be microfiber can be opened, carded and cross wrapped to form a web, and then needle punched to produce a three-dimensional entangled nonwoven fabric, and then subjected to shrinkage processing to increase the density. Stabilizes the shape of nonwoven fabric by filling water-soluble polymers such as polyvinyl alcohol and carboxymethyl cellulose as water-soluble binders in order to facilitate the process and post-processing and to improve the air permeability of leather-like sheets. Process of impregnating polyurethane, which is a polymer elastomer, into a sheet, coagulating and washing with water to fill a polyurethane elastic material in the nonwoven fabric, and minimizing the fiber by removing all extracted components of the composite fiber under solvent as caustic soda. Finally, the surface of the surface is buffing with sand paper. It trimmed know haejugo through the dyeing and softening agents such as process step of flexible when - it is possible to obtain a teumul. Each of these processes can be reordered according to the use of artificial leather, for example, shoes, clothing, sundries, gloves, etc., or may add or omit other processes.

In other words, the manufacturing method of the known artificial leather is a non-woven fabric manufacturing process, water-soluble polymer pretreatment process, polyurethane impregnation process, extraction component extraction process for extracting the extracted components of the composite fiber, hair forming process, dyeing process, etc. It is an important process that determines the quality and characteristics of a product.

In manufacturing non-woven citro-tro artificial leather, various methods are commonly used to obtain elasticity and wear strength. For example, Japanese Patent Laid-Open No. 2000-303365 has a method of improving elasticity by heat-treating a buffed sheet prior to dyeing. Japanese Patent Laid-Open No. 2001-214376 discloses a method of coating a polymer resin on the surface of a dyed sheet.

The method of heat-treating the buffed sheet-water before dyeing is excellent in elasticity and surface suede effect, but the process is not only complicated but also hard by touch due to excessive heat treatment and weak wear strength when used for gloves such as mountain bikes and baseball gloves. It has a disadvantage. On the other hand, the method of coating the polymer resin on the surface in order to improve the wear strength is excellent in the wear strength, but has no suede effect on the surface and is hard to feel due to the characteristics of the coated polymer resin itself is limited to the use, and also coating Since the polymer resin used in the solvent type has a disadvantage that is harmful to the human body.

On the other hand, Japanese Laid-Open Patent Publication No. 2002-180380 proposes a method of impregnating artificial leather in an aqueous dispersion of a silicone compound to fill 0.5 to 5% by weight of the silicone compound in order to improve wear resistance of the artificial leather.

However, the artificial leather manufactured by the above method has a problem that the elasticity of the artificial leather is lowered because the silicone compound is filled up inside the artificial leather.

An object of the present invention is to manufacture artificial leather which greatly improves the wear strength without reducing the suede effect and elasticity while solving such a conventional problem.

The present invention is to coat (coated) the silicone rubber on the surface of artificial leather to significantly improve the wear strength without reducing the suede effect and elasticity of artificial leather.

The artificial leather having excellent wear strength of the present invention is an artificial leather in which a polyurethane elastic body is filled (impregnated) in a nonwoven fabric in which microfine fibers of 0.3 denier or less are entangled with each other, and the hair is formed on the surface thereof. Silicone rubber is coated (coated) on the surface of the artificial leather in which the hair is formed.

In addition, the manufacturing method of artificial leather according to the present invention is (i) a web consisting of the extract component and the fiber-forming component and the two-component composite fiber having a single yarn fineness of 0.3 denier or less after the extraction component is opened, carded and cross-wrapped. ) And then needle punching to prepare a nonwoven fabric, (ii) treating the manufactured nonwoven fabric with an aqueous alkali solution to remove (extract) the extract component in the two-component composite fiber, and (iii) the nonwoven fabric from which the extract component is extracted. Filled with a water-soluble polymer, (i) filled (impregnated) with a polyurethane resin in a nonwoven fabric filled with a water-soluble polymer, coagulated, washed with water, and then heat treated, and (iii) a nonwoven fabric filled with a polyurethane resin was buffed. After forming the hair on the surface, it is dyed to a desired color, and the silicone rubber composition is coated on the surface of the dyed artificial leather.

In this case, the nonwoven fabric filled with the polyurethane resin may be sliced in half just before buffing.

Another artificial leather manufacturing method of the present invention is (i) the web (Web) by the opening, carding and cross-lapping two-component composite fiber consisting of the extract component and the fiber-forming component and the single yarn fineness after the extraction component removed 0.3 denier or less After fabrication, needle punching is used to prepare a nonwoven fabric, (ii) filling (impregnating) a polyurethane resin into the nonwoven fabric, coagulating and washing in a coagulation bath, and (iii) treating the nonwoven fabric with an aqueous alkali solution to give a bicomponent composite fiber. After removing (extracting) the extracted components, they are heat-treated at the same time as drying, and (b) buffing the heat treated nonwoven fabric to form hair on the surface of the nonwoven fabric, and then dyed to a desired color, and (ⅴ) dyed artificial leather. It is characterized by coating the silicone rubber composition on the surface of the.

In this case, the water-soluble polymer may be first filled immediately before filling the nonwoven fabric with polyurethane resin, and the nonwoven fabric filled with the polyurethane resin may be sliced and sliced immediately before butting.

Hereinafter, the present invention will be described in detail.

The bicomponent conjugate fiber used in the present invention is a fiber in which the fiber-forming component, which is a polymer material capable of forming continuous fibrils, and the extract component, which is a polymer material serving as a binder for binding fibrils, are conjugated. In the present invention, it is preferable to use an island-in-the-sea composite fiber. Of course, the present invention does not particularly limit the bicomponent composite fiber cross-sectional shape or components. In general, in the case of island-in-the-sea composite fibers, polyethylene terephthalate or nylon-6 is used as the island component (fiber forming component), and polystyrene, polyethylene, and copolymer poly with different solvent components and solvent solubility as sea components (extract component). Ester etc. are used.

In particular, nylon-6 is suitable as a sea component for the purpose of producing dense artificial leather by increasing the density of nonwoven fabrics, and polyester, polyethylene, etc., copolymerized with 5-sodium sulfoisophthalic acid as the sea component, It is suitable in workability. The fineness of the island component after micronization is 0.3 denier or less, more preferably 0.1 denier or less, which is good for flexibility and surface appearance improvement. This is not only to obtain a flexible sheet, but also to prevent the strong deterioration of the sheet by forming a fine entanglement in three dimensions after the micronization treatment.

Such two-component composite fibers are stapled and manufactured in a three-dimensional interwoven nonwoven fabric by performing carding, cross-lapping, and needle punching processes sequentially.

Next, the prepared nonwoven fabric is treated with an aqueous alkaline solution to remove (extract) the extracted components in the two-component composite fiber. As aqueous alkali solution, caustic soda solution is mainly used. In this process, the ratio of weight loss time to caustic soda content is a very important factor. For example, when the content of caustic soda is low, the weight loss time should be lengthened, and it is preferable to adjust the amount of caustic soda to an appropriate level in consideration of workability. According to the present invention, the extraction time of the sea component (extraction component) was 5-15 minutes, and the concentration of caustic soda is preferably 5-20%.

Next, the water-soluble polymer is filled in the nonwoven fabric (sheet material) from which the extract component is extracted as described above. Specifically, the sheet is immersed in an aqueous solution of 5 to 15% polyvinyl alcohol (hereinafter PVA) having a polymerization degree of 500 to 700, squeezed at a suitable pressure, and dried at a temperature of 110 ° C. or higher. This stabilizes the nonwoven fabric by filling the PVA at the intersection of the fiber surface and the fiber. Next, a polyether-based polyurethane (hereinafter PU) is used as a solvent in a sheet material filled with a water-soluble polymer, and a polyurethane resin solution prepared by adding a surfactant or a coloring pigment is impregnated. In addition, since the content of PU depends on the concentration of the impregnation solution, the gap between the impregnation rolls, and the density of the nonwoven fabric to be impregnated, it should be adjusted according to the characteristics of the sheet. Preferably, the amount of PU is preferably about 20 to 45% by weight in solids relative to the weight of the leather sheet. In the present invention, the PU impregnation process may be performed after the extraction component (sea component) removal process as described above, or the extraction component (sea component) removal process may be performed after the PU impregnation process first. Next, the PU-impregnated sheet is dried after washing with water in a coagulation bath and simultaneously heat-treated. If the extraction component is removed after PU impregnation, the extraction component is removed and heat treated simultaneously with drying. The temperature of the coagulation bath is 30-40 ℃, the DMF concentration in the coagulation tank is 10-40%, and the water is sufficiently washed at 80-90 ℃ to completely remove PVA, which is a water-soluble binder. After washing, heat treatment is performed simultaneously with drying to give elasticity. The heat treatment temperature is suitable for 130 ~ 180 ℃. If the heat treatment temperature is less than 130 ℃ the lack of heat treatment effect does not exhibit the desired elasticity, if the heat treatment temperature exceeds 180 ℃, because the touch is too hard to apply to the desired application, temperature control is most important Do.

Temperature control should be set appropriately in consideration of workability. Of course, in the case of impregnating the PU first and removing the sea component, the heat treatment is performed simultaneously with the drying after the sea component removal process. In the present invention, it is important to perform the heat treatment method to impart elasticity before the buffing process, that is, before forming the hairs.

After the buffing process is performed to form the surface napped with the sheet material thus obtained, dyeing is carried out under ordinary conditions, and the silicone rubber composition is coated on the surface. Silicon coating is preferably carried out by a gravure method rather than a conventional laminating method or knife coating. The reason is that the laminating coating can be used only for very limited applications because the thickness of the coating layer becomes hard, and the coating is uneven due to the fiber on the surface. This is because application to a high-quality product is difficult. Therefore, the coating of artificial leather surface is most suitable for gravure coating that can be easily adjusted and uniformly applied. As silicone rubber, two-component silicone rubber is preferable. In this case, there is an advantage in that the curing speed can be controlled by adjusting the amount of the curing agent according to the characteristics of the product. If the one-component silicone is used, the silicone rubber is hardened during the coating process, so that uniform coating is not possible and hardening occurs at room temperature.

In the present invention, in particular, the viscosity of the silicone rubber is important, the most suitable viscosity is preferably to use the silicone rubber having a viscosity within 10,000 ~ 50,000 cps. If the viscosity of the silicone rubber is less than 10,000 cps, there is a problem of weak wear strength due to the penetration of silicone rubber into the sheet before curing. If the viscosity of the silicone rubber exceeds 50,000 cps, the viscosity is too high to penetrate into the sheet. There is a problem that the coating layer is thickened so that the suede effect is not expressed and the touch is hard.

The coating amount of the silicone rubber according to the present invention is suitable 5 ~ 40g / ㎡. If the coating amount of silicon is less than 5g / ㎡, the coating amount of the surface is insufficient, the wear strength is insufficient, if the coating amount exceeds 40g / ㎡ there is a problem that the coating is excessive, there is no suede effect and the touch is hard.

After coating, the silicone rubber should be cured to ensure sufficient adhesion to the sheet. In this case, the amount of the curing agent and the curing temperature are important. Usually, platinum, rhodium, tin, etc. are used as the curing agent, but platinum which can be cured even at a low temperature is the best curing agent suitable for the present invention. The amount of the curing agent should be set in consideration of the curing rate, the most preferable 0.05 ~ 2% by weight based on the silicone rubber, the curing temperature is suitable 120 ~ 180 ℃. If the amount of the curing agent is less than 0.05% by weight and the curing temperature is less than 120 ℃ the curing of the silicone rubber is slow and the surface of the product is sticky there is a problem that contamination occurs due to adhesion of dust and the like. If the amount of the curing agent exceeds 2% by weight or the curing temperature exceeds 180 ℃ there is a disadvantage that the surface is non-uniform and hard to touch before the silicone rubber penetrates into the sheet.

   Artificial leather of the present invention prepared by the method described above is coated with a thin film of silicone rubber on the surface, has a suede effect and excellent elasticity and wear strength.

Hereinafter, the present invention will be described in more detail with reference to the following examples. However, the present invention is not limited only to the following examples.

Example 1

A composite fiber staple of 3.5 denier, 51 mm in length and 12-18 pieces / inch crimp was prepared using 70 wt% of nylon-6 as a coating component and 30 wt% of copolyester as a sea component. The staple thus obtained was opened, carded and needle punched to produce a three-dimensional entangled nonwoven fabric having a weight of 750 g / m 2, a thickness of 3.0 mm, and an apparent density of 0.225 g / cm 3.

The nonwoven fabric thus prepared was continuously subjected to weight loss processing for 10 minutes in a 10% aqueous solution of caustic soda and 1% aqueous solution of an ionic penetrant, and washed with water at 80 ° C. and dried. At this time, the fibers were micronized to about 0.07 denier. Next, the micronized substrate was padded and dried in a 10% aqueous solution of PVA having an average degree of polymerization of 500 and a degree of saponification of 85%. At this time, the content of PVA was adjusted to 12% by weight relative to the fiber. Subsequently, to impart elasticity to the form stabilized substrate, an impregnated DMF solution of 12% polyether-based polyurethane having a 100% modulus of 30 kg / cm 2 was impregnated into the nonwoven fabric, followed by a gap of 80% to sufficiently fill the polyurethane inside the substrate. Padded and solidified with (Gap), washed with a conventional method and then heat-treated while drying at a temperature of 130 ℃. The density of the base material obtained at this time was 0.344 g / cm <3>.

After slicing, the substrate is divided into half and the surface is buffed with sandpaper 320 mesh to form hairs, and then dyed. Then, the gravure coating method is applied to the surface of the dyed artificial leather with a viscosity of 25,000 cps. Coating to 5g / ㎡, and cured at a temperature of 150 ℃ to prepare an artificial leather coated with a silicone resin on the surface.

 The results of evaluating various physical properties of the manufactured artificial leather are shown in Table 1.

Example 2

Except for changing the heat treatment temperature to 180 ℃ was prepared artificial leather coated with a silicone resin on the surface in the same manner as in Example 1. The results of evaluating various physical properties of the manufactured artificial leather are shown in Table 1.

Example 3

Except for changing the silicone rubber coating amount to 40g / ㎡ was prepared in artificial leather coated with a silicone resin on the surface in the same manner as in Example 1. The results of evaluating various physical properties of the manufactured artificial leather are shown in Table 1.

Example 4

Except for changing the heat treatment temperature to 180 ℃ and changing the silicone rubber coating amount to 40g / ㎡ was prepared in artificial leather coated with a silicone resin on the surface in the same manner as in Example 1. The results of evaluating various physical properties of the manufactured artificial leather are shown in Table 1.

Example 5

A composite fiber staple of 3.5 denier, 51 mm in length and 12-18 pieces / inch crimp was prepared using 70 wt% of nylon-6 as a coating component and 30 wt% of copolyester as a sea component. The staple thus obtained was opened, carded and needle punched to produce a three-dimensional entangled nonwoven fabric having a weight of 750 g / m 2, a thickness of 3.0 mm, and an apparent density of 0.225 g / cm 3.

The nonwoven fabric thus prepared was impregnated with 100% modulus of 30 kg / ccm2 polyether-based polyurethane DMF solution to the nonwoven fabric, and then padded with a gap of 80% to sufficiently fill the polyurethane inside the substrate. After coagulation, the solution was washed with water at 80 DEG C in a conventional manner, and then dried. At this time, the fibers were micronized to about 0.07 denier. Subsequently, a substrate filled with a polyurethane resin was padded and dried in a 10% aqueous solution of PVA having an average degree of polymerization of 500 and a degree of saponification of 85%.

Subsequently, the PVA-filled substrate was subjected to weight loss processing for 10 minutes in a 10% aqueous solution of caustic soda and 1% aqueous solution of ionic penetrant, washed with water at 80 ° C, and then heat-treated while drying at a temperature of 130 ° C. The density of the base material obtained at this time was 0.344 g / cm <3>.

Next, the substrate is sliced into half and the surface is buffed with sandpaper 320 mesh to form a hair, and then dyed. The gravure coating method is applied to the surface of the dyed artificial leather with a viscosity of 25,000 cps using a gravure coating method. Coding to / ㎡, and cured at a temperature of 150 ℃ to prepare an artificial leather coated with a silicone resin on the surface. The results of evaluating various physical properties of the manufactured artificial leather are shown in Table 1.

Comparative Example 1

An artificial leather (silicone resin not coated) was prepared under the same conditions as in Example 1 except that the silicone rubber composition was not coated on the surface of the artificial leather. The results of evaluating various physical properties of the manufactured artificial leather are shown in Table 1.

Comparative Example 2

The artificial leather (silicon resin not coated) was prepared under the same conditions as in Example 1 except that the heat treatment temperature was changed to 180 ° C. and the silicone rubber composition was not coated on the surface of the artificial leather. The results of evaluating various physical properties of the manufactured artificial leather are shown in Table 1.

Various physical properties of the artificial leather in the present invention was evaluated by the following method.

Tear strength

It was evaluated by the ASTM D2261 method.

Wear strength

It was evaluated by the ASTM D3884 method.

Elongation recovery rate (%)

It was evaluated by the ASTM D1117 method.

Filling property

It was evaluated by the ASTM D4970 method.

Elongation recovery rate

After repeating the procedure of leaving the sample for 1 hour after 30% elongation 5 times, the recovery rate was calculated by substituting the measured sample length (L1) and the initial sample length (L) in the following equation.

Feel and appearance

The sensory test of 10 experts judged that the abnormality of P was good ◎, 7 if 8-8 judged good, △ if 5-6 judged good, △, × 4 if judged good. Each was separated.

Property evaluation result division Example 1 Example 2 Example 3 Example 4 Example 5 Comparative Example 1 Comparative Example 2 Tear strength (㎏) Longitudinal direction 5.1 4.5 5.5 4.8 5.0 5.1 4.2 Width direction 4.8 4.2 5.0 4.7 4.9 4.8 4.0 Wear strength 13,213 13,500 16,600 19,808 13,400 1,9200 2,423 Elongation rate (%) 94 97 96 97 95 85 94 Peeling property (grade) 4 ~ 5 4 ~ 5 4 ~ 5 4 ~ 5 4 3 3 ~ 4 touch ○ ○ ○ ○ ◎ ○ △ Appearance (suede effect) ◎ ◎ ○ ○ ◎ ◎ ◎

The present invention has a silicone rubber is coated (coated) on the surface of the artificial leather has excellent suede effect and elasticity, but also excellent wear strength.

Claims (16)

In an artificial leather in which a polyurethane elastic body is filled (impregnated) in a nonwoven fabric in which fine fibers of 0.3 denier or less are entangled with each other, and the hair is formed on the surface thereof, on the surface of the artificial leather where the hair is formed Artificial leather with excellent wear strength, characterized in that the silicone rubber is coated (coated). The artificial leather of claim 1, wherein the coating (coating) area of the silicone rubber is 80% or more of the total surface area. The artificial leather of claim 1, wherein the coating amount of the silicone rubber is 5 to 40 g / m 2. The artificial leather with excellent wear strength according to claim 1, wherein the silicone rubber is a two-component silicone rubber. The artificial leather of claim 1, wherein the silicone rubber has a viscosity of 10,000 to 50,000 cps. (Iii) Web is manufactured by opening, carding and cross-lapping two-component composite fibers consisting of extraction components and fiber-forming components and having a single yarn fineness of 0.3 denier or less after removal of the extraction components, and then needle punching them to form a nonwoven fabric. (Ii) treating the prepared nonwoven fabric with an aqueous alkali solution to remove (extracting) the extract component in the two-component composite fiber, (i) filling the nonwoven fabric from which the extract component has been extracted, and (i) water-soluble polymer. After filling (impregnating) the polyurethane resin into the filled non-woven fabric, solidifying, washing and heat-treating it, and (b) forming the hair on the surface of the nonwoven fabric by buffing the non-woven fabric filled with the polyurethane resin, and then desired color. And (i) a method of producing artificial leather having excellent wear strength, characterized by coating a silicone rubber composition on the surface of the dyed artificial leather. The method of manufacturing artificial leather with excellent wear strength according to claim 6, wherein the polyurethane resin is filled in half by slicing immediately before buffing the nonwoven fabric filled with the polyurethane resin. The method for producing artificial leather having excellent wear strength according to claim 6, wherein the non-woven fabric filled with polyurethane resin is solidified in water, washed with water, and then subjected to a heat treatment temperature of 130 to 180 ° C. (Iii) Web is manufactured by opening, carding, and cross-lapping bicomponent composite fibers consisting of extraction components and fiber-forming components and having single yarns of 0.3 Da or less after removal of the extraction components, and then needle punching them to produce a nonwoven fabric. (Ii) filling (impregnating) a polyurethane resin into the nonwoven fabric, coagulating and washing in a coagulation bath, and (iv) treating the nonwoven fabric filled with the polyurethane resin with an aqueous alkali solution to extract the components in the two-component composite fiber. After removing (extracting), drying and heat treatment at the same time, (,) heat treated nonwoven fabric to form hair on the surface of the nonwoven fabric, and then dyed to the desired color, and (ⅴ) silicone on the surface of dyed artificial leather Manufacturing method of artificial leather with excellent wear strength, characterized in that the coating of the rubber composition solution. 10. The method of claim 9, wherein the nonwoven fabric is filled with a water-soluble polymer immediately before the polyurethane resin is filled. 10. The method of claim 9, wherein the nonwoven fabric filled with the polyurethane resin is sliced and halved immediately before buffing. The method for producing artificial leather having excellent wear strength according to claim 9, wherein the heat treatment temperature performed at the same time as drying after removing (extracting) the extraction component is 130 to 180 ° C. The method for producing artificial leather having excellent wear strength according to claim 6 or 9, wherein a curing agent of 0.05 to 2% by weight relative to the weight of silicone rubber is added to the silicone rubber composition liquid. The method for producing artificial leather having excellent wear strength according to claim 6 or 9, wherein the silicone rubber composition liquid coated (coated) on the surface of artificial leather is cured at a temperature of 130 to 180 ° C. 10. The wear rubber according to claim 6 or 9, wherein the silicone rubber is a two-component silicone rubber whose coating area is 80% or more of the total surface area, and the coating amount is 5 to 40 g / m 2. Excellent manufacturing method of artificial leather. The method for producing artificial leather having excellent wear strength according to claim 6 or 9, wherein the silicone rubber has a viscosity of 10,000 to 50,000 cps.

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