KR100851300B1 - Artificial leather using base of knit and peparing method the same - Google Patents

Abstract

An artificial leather by using knitted goods as a base and a manufacturing method thereof are provided to lower the manufacture cost by using the low cost filament and the highly contractible filament, and to manufacture the product easily. A surface of the knitted sheet is formed of a 0.5-1.0 denier polyester mono-filament. The center part of the knitted sheet is formed of the triple-fold highly-contractible filament. Both surfaces napping knit formed by napping the polyester filament is wet-impregnated in a polyurethane solution, exchanged by the solvent under a solidification solution and dried by a dry process. The fineness of the highly contractible filament of the center part of the knit sheet is 50-300 deniers. Both-surfaces of the knitted sheet are napping-treated by passing the knitted sheet between a pair of rollers for forming napping in which needles for forming napping have a regular density. The solidification solution for forming the napping knit is formed of water, or a mixed solution of water and DMF(Di-Methyl-Formamide).

Description

Artificial leather based on knitted fabric and its manufacturing method {ARTIFICIAL LEATHER USING BASE OF KNIT AND PEPARING METHOD THE SAME}

The present invention relates to an artificial leather manufactured using a knitted fabric composed of general filament fibers and high-shrinkable filament fibers as a base material, and more particularly, because it is manufactured using a very inexpensive knitted fabric as a base material, it is easy to manufacture and production cost. The present invention relates to artificial leather and a method of manufacturing the same based on a knitted fabric which is greatly reduced.

Artificial leather uses a nonwoven fabric as a base material, which is formed by wet impregnation or coating processing of a polyurethane resin on the nonwoven fabric, and is similar to natural leather in terms of its structure, functionality, and various physical properties, and rather, it has defects of natural leather. While it has excellent advantages to complement, it is in the spotlight as an alternative material of natural leather because it is cheaper than natural leather.

By the way, the largest share of the manufacturing cost of artificial leather is the price of the substrate to which the polyurethane resin is converted into a leather structure, and has the characteristic that the manufacturing cost of artificial leather depends on the price of the substrate.

Regarding the conventional artificial leather and its manufacturing method, Korean Unexamined Patent Publication No. 1985-8373 (Invention name: Manufacturing method of suede artificial leather with excellent lighting effect), Korean Unexamined Patent Publication No. 1996-23484 (Invention) The present invention discloses an artificial leather based on a nonwoven fabric prepared by impregnating and solidifying a water-soluble polymer in a nonwoven fabric of a fiber material as a base material and filling a nonwoven fabric with a polymer elastomer. Since the conventional artificial leather is manufactured using a non-woven fabric that is expensive and difficult to manufacture, it has a problem that the manufacturing cost increases significantly.

In addition to the artificial leather based on the non-woven fabric of the general fiber material described above, Korean Unexamined Patent Publication No. 1996-23482 (Invention name: manufacturing method of artificial leather excellent in color durability and touch), Republic of Korea Patent Publication No. 1999- In No. 57603 (name of the invention: a method of manufacturing an ultra-fine microfibre nonwoven artificial leather), first, a microfiber of a yarn is manufactured, and the microfiber is short-fiber to manufacture a needle punching nonwoven sheet, and the nonwoven fabric sheet is impregnated with a porous polyurethane resin. The present invention relates to an artificial leather based on a microfiber sheet manufactured by dyeing after a weight loss process and a method of manufacturing the same. As described above, the artificial leather manufactured using the nonwoven fabric of the microfiber material has the characteristics of improving quality than the artificial leather based on the nonwoven fabric of the general fiber material, but is manufactured using the very expensive microfiber yarn It has a problem that the manufacturing cost is significantly higher than the artificial leather based on the nonwoven fabric of the material.

In addition, Korean Laid-Open Patent Publication No. 2000-20827 (name of the invention: a method of manufacturing a polyester fabric for artificial leather) uses artificial fibers composed of ultrafine polyester composite fibers of less than 0.3 denier and heat-sealing copolyester. A method for producing a polyester fabric for leather is disclosed, and Korean Patent Publication No. 0681757 (Invention name: Manufacturing method of suede-like artificial leather using nylon island-in-the-sea yarn and general polyester yarn), Republic of Korea Patent Publication No. 0625110 No. (name of the invention: a method for producing a polyurethane-impregnated suede artificial leather) discloses a method for producing a suede artificial leather composed of a sheet containing a sea island which can be eluted into microfiber as a substrate. The artificial leather described above has a problem in that the manufacturing cost is greatly increased because it is manufactured using very expensive microfiber yarns and sea island yarns.

In conclusion, the conventional artificial leather is manufactured using a material including a non-woven fabric, a microfiber yarn or an island-in-the-sea yarn which can be eluted as a microfiber yarn, and these materials have a common point that they are expensive and the manufacturing process is very difficult. Therefore, there is a fundamental problem that the manufacturing cost of artificial leather manufactured by using the material including the island-in-the-sea yarn which can be eluted into nonwoven fabric, microfiber yarn or microfiber yarn also has to rise significantly.

Accordingly, an object of the present invention is to provide an artificial leather and a method of manufacturing the same, which are manufactured using a knitted fabric composed of general filament long fibers and high shrinkable filament fibers, which are easy to manufacture and very inexpensive.

In order to solve the above problems, in the present invention, both surfaces of the polyester monofilament long fibers of 0.5 to 1.0 denier, the polyester portion of both surfaces of the knitted sheet consisting of a triple structure of high shrinkable polyester filament fibers An artificial leather is provided based on a knitted fabric consisting of a double-sided knitted fabric formed by raising the filament long fiber portion by wet impregnation in a polyurethane solution, solvent exchange under a coagulating solution, and dry dried.

In addition, in the present invention, both surfaces are knitted to form a triple sheet of polyester monofilament long fiber of 0.5 to 1.0 denier, the central portion of the highly shrinkable polyester filament fiber to form a knitted sheet, both surfaces of the knitted sheet Napping to form a double-sided brushed knit fabric having a brushed layer of a constant thickness, impregnating the double-sided brushed knit fabric with a polyurethane solution to form a polyurethane-impregnated brushed knit fabric, and the polyurethane-impregnated brushed knit fabric under a coagulating solution There is provided a method of producing artificial leather based on a knitted fabric comprising the steps of forming a polyurethane filled brushed knit in exchange, and drying the polyurethane filled brushed knit.

The artificial leather based on the knitted fabric produced by the present invention is manufactured using a low-cost knitted sheet composed of general filament filaments and high-shrinkable filament fibers as a base material, and thus is very easy to manufacture compared to conventional artificial leather. The cost of manufacturing is significantly reduced by half compared to conventional artificial leather.

The structure of the artificial leather based on the knitted fabric of this invention is demonstrated in detail with reference to an Example.

The artificial leather of the present invention does not use expensive microfiber or island-in-the-sea yarn at all, and it is easy to brush the 0.5-1.0 denier polyester monofilament long fiber, and 50-300 denier highly shrinkable poly which can be easily shrunk. It is constructed by applying a knitted sheet knitted with ester filament fibers as a substrate, and more specifically, 0.5 to 1.0 denier polyester monofilament long fibers are knitted on both surfaces, and the polyester monofilament long fibers on both surfaces It has the characteristic comprised by applying to the base part the triplet knitted fabric sheet which 50-300 denier highly shrinkable polyester filament fiber knits in the center part between.

The filament filaments knitted on both surfaces of the knitted sheet, which is a base material of artificial leather, can use filament filaments of various materials that are commercially and industrially applied. Among them, filament filaments are made of polyester and have a shortness of 0.5 to 1.0 denier. The use of monofilament filament is easy to brush and handle, and has excellent affinity with polyurethane, the leather structure of artificial leather, can provide soft touch to artificial leather, and various mechanical properties required for the base of artificial leather. It is preferable at the point of sufficient satisfaction.

If the single fineness of the polyester monofilament long fibers forming both surfaces of the knitted sheet, which is a base material of artificial leather, is less than 0.5 denier, the fineness of the polyester monofilament long fibers is poor and the needles are raised when raising both surfaces of the knitted sheet. When the needle occurs, the workability decreases, and when the single fineness of the polyester monofilament long fiber exceeds 1.0 denier, the rigidity of the polyester monofilament long fiber is improved, but the knitted fabric containing the polyester monofilament long fiber Soft touch is not expressed in the artificial leather manufactured using the sheet.

In addition, in order to control the thickness of the artificial leather using the knitted sheet as a substrate and to improve the mechanical properties such as bending property, tensile strength and pile strength performance, the high-shrinkable fiber knitted on the central portion of the knitted sheet which is the base material of artificial leather Although high shrinkable fibers of various materials that are commercially and industrially used may be used, among them, the high shrinkable polyester filament fibers may include a high shrinkable filament fiber made of a polyester material and having a single fineness of 50 to 300 denier. The thickness of the artificial leather produced using the knitted sheet can be easily adjusted, and is preferable in view of satisfying various mechanical properties required for the substrate of the artificial leather.

If the shortness of the high-shrinkage polyester filament fibers forming the central portion of the knitted sheet, which is the base material of artificial leather, is less than 50 denier, the thickness of the artificial leather produced using the knit sheet containing the high-shrinkage polyester filament fibers is very When the shortness of the shrinkable polyester filament fibers exceeds 300 denier, the elasticity of the artificial leather produced using the knitted sheet containing the highly shrinkable polyester filament fibers is reduced, and at the same time the shrinkable polyester filament fibers Excessive investment in equipment for processing will lead to an increase in the manufacturing cost of artificial leather.

Such polyester monofilament filaments and highly shrinkable polyester filament fibers are much cheaper than microfiber or island-in-the-sea yarns and are easy to knit, so using these general polyester monofilament long fibers and highly shrinkable polyester filament fibers The price of the knitted sheet to be knitted can be greatly reduced.

However, in order to manufacture artificial leather, the polyurethane solution must easily penetrate into the inside of the substrate, and the knitted sheet in which both surfaces are knitted with polyester monofilament long fibers has a dense internal structure of the polyester monofilament long fiber portion. There is a problem that it is difficult to easily penetrate the polyurethane solution.

In order to solve this problem, in the present invention, the polyester monofilament filaments, the central portion of the polyester sheet monofilament filaments on both surfaces of the knitted sheet knitted in a triple structure of high shrinkage polyester filament fibers, A low density brushed layer having a constant thickness is formed on both surfaces of the knitted sheet, but the raised layer formed on both surfaces of the knitted sheet has a thickness sufficient to penetrate the polyurethane solution to form a practical leather structure. It must be formed.

The polyurethane solution easily penetrated into the low density brushed layer formed by the brushing process is solidified by solvent exchange and converted into a leather structure.

As described above, the knitted sheet having raised layers on both surfaces is wet-impregnated with a polyurethane solution containing polyurethane, which is converted into a leather structure, as a key component, and the polyurethane solution penetrates into the raised layer of the knitted sheet. Urethane impregnated brushed knit is formed.

The polyurethane solution for wet impregnating a knitted sheet is composed of a polyurethane, which is converted into a leather structure, and dimethyl formamide (DMF), which is a solvent for the polyurethane, in a predetermined mixing ratio, optionally in the polyurethane and dimethyl formamide. Additional components such as various additives, adjuvants, etc. may be mixed to form the polyurethane solution.

By the wet impregnation of the polyurethane solution composition as described above, the polyurethane solution is uniformly penetrated into the brushed layer of the knitted sheet to form a polyurethane impregnated brushed knitted fabric.

The polyurethane solution that has penetrated the polyurethane impregnated brushed knitted fabric is solidified by solvent exchange of a coagulation solution, so that the polyurethane of the polyurethane solution is converted into a leather structure.

Specifically, when the polyurethane impregnated brushed knit is deposited in the coagulation solution, dimethyl formamide, which is a solvent of the polyurethane solution of the polyurethane impregnated brushed knit, is eluted into the coagulation solution, and the solvent is exchanged and the solid polyurethane is solidified into the leather structure. do.

By arbitrarily adjusting the composition of the coagulating solution for solvent-exchanging the polyurethane impregnated brushed knitted fabric, it becomes possible to control the physical properties of the leather structure formed by solidifying the polyurethane of the polyurethane solution of the polyurethane impregnated brushed knitted fabric. Therefore, in the present invention, the coagulation solution for solvent-exchanging the polyurethane impregnated brushed knitted fabric uses water alone or a mixed coagulation liquid formed by mixing water and dimethyl formamide in a constant mixing ratio. By controlling the mixing ratio between the dimethyl formamide and the physical properties of the leather structure can be arbitrarily adjusted.

When the solidified impregnated brushed knitted fabric is impregnated with the coagulating solution, dimethyl formamide, which is a solvent of the polyurethane solution penetrated into the brushed layer of the polyurethane impregnated brushed knitted fabric, is eluted, and the polyurethane dissolved in the polyurethane solution is dissolved. The solvent-exchanged, solidified into the leather structure, and the polyurethane solidified into the leather structure is in close contact with the brushed layer of the polyurethane impregnated brushed knitted fabric, thereby forming a polyurethane-filled brushed knitted fabric forming the form of artificial leather.

The artificial based on the knitted fabric of the present invention by removing the water or dimethyl formamide remaining on the surface of the polyurethane filled brushed knitted fabric by naturally drying the polyurethane filled brushed knitted fabric forming the form of artificial leather or by dry drying by hot air or the like. Leather is formed.

The artificial leather based on the knitted fabric constructed as described above is manufactured using a knitted sheet fabricated using polyester monofilament filaments and highly shrinkable polyester filament fibers, which are very inexpensive, and thus, conventional nonwoven fabrics and microfiber yarns. Compared to the artificial leather manufactured by using the material and the island-in-the-sea yarn material as a base material, the manufacturing cost can be greatly reduced.

The manufacturing method of the artificial leather based on the knitted fabric of this invention is demonstrated in detail with reference to an Example.

First, the method of manufacturing artificial leather based on the knitted fabric of the present invention is a triple structure of polyester monofilament filaments having both surfaces easily brushed, and highly shrinkable polyester filament fibers having a central portion controlling the thickness of artificial leather. It comprises a step of knitting to form a knitted sheet (step S10).

In the artificial leather of the present invention, 0.5 to 1.0 denier polyester monofilament long fibers are knitted on both surfaces, and 50 to 300 denier highly shrinkable polyester filament fibers are formed at the center between the polyester monofilament long fibers on both surfaces. It consists of applying the knitted sheet of the triple structure knitted as a base material.

If the single fineness of the polyester monofilament long fibers forming both surfaces of the knitted sheet, which is a base material of artificial leather, is less than 0.5 denier, the fineness of the polyester monofilament long fibers is poor and the needles are raised when raising both surfaces of the knitted sheet. When the needle occurs, the workability decreases, and when the mono fineness of the polyester monofilament filament exceeds 1.0 denier, the stiffness of the polyester monofilament filament is improved, but the soft touch is not expressed in artificial leather.

In addition, when the shortness of the high-shrinkage polyester filament fibers forming the central portion of the knitted sheet, which is the base material of artificial leather, is less than 50 denier, it is very difficult to control the thickness of the artificial leather, and the shortness of the shrinkable polyester filament fibers is 300 denier. If it exceeds, the elasticity of the artificial leather is lowered and the equipment investment for processing the shrinkable polyester filament fibers is excessive.

To produce artificial leather by knitting in a knitting machine with the above-mentioned 0.5 ~ 1.0 denier polyester monofilament filaments on both surfaces, 50 to 300 denier high shrinkable polyester filament fibers that can be easily shrunk to the center The knitted sheet which is a base material for is manufactured.

The manufacturing method of artificial leather based on the knitted fabric of the present invention includes a step of raising both surfaces of the knitted sheet to form a double-sided brushed knitted fabric having a brushed layer of a constant thickness (step S20).

Since the knitted sheet knitted only with the general filament based on the step S10 is difficult to easily penetrate the polyurethane solution because its internal structure is dense, each surface of the knitted sheet knitted only with the general filament is raised A low density brushed layer having a predetermined thickness is formed, and the brushed layer is formed to a thickness sufficient to penetrate the polyurethane solution to form a practical artificial leather.

Specifically, the knitted sheet formed in step S10 is passed through a pair of brushing rollers having brushed needles having a predetermined density, respectively, and the knitted sheet is formed by brushing needles respectively formed on the pair of brushing rollers. The part of the polyester monofilament long fiber which is both surfaces of a sheet is brushed, and a brush layer is formed.

The polyurethane solution which easily penetrated into the raising layer of the knitted sheet formed by brushing by a pair of raising rollers was solidified by solvent exchange and converted into a leather structure.

The method for producing artificial leather based on the knitted fabric of the present invention includes the step of impregnating the double-sided brushed knit fabric with a polyurethane solution to form a polyurethane-impregnated brushed knit fabric (step S30).

The knitted sheet having the raised layer on both surfaces is wet-impregnated with a polyurethane solution to infiltrate the polyurethane solution into the raised layer of the knitted sheet to form a polyurethane impregnated brushed knitted fabric.

The polyurethane solution for wet impregnating a knitted sheet is formed by mixing polyurethane, which is converted into a leather structure, and dimethyl formamide, which is a solvent, in a constant mixing ratio, and is formed on the brushed layer of the knitted sheet by wet impregnation of the polyurethane solution. The polyurethane solution penetrates uniformly.

Specifically, in step S20, the knitted sheet, which is treated with both surfaces, is immersed in the impregnation tank containing the polyurethane solution for a predetermined time or passed at a constant rate, so that the polyurethane sheet is wet impregnated with the polyurethane solution. It is to form a polyurethane impregnated brushed knitted fabric which makes the state which penetrated uniformly into the brushed layer of a knitted sheet.

The method for producing artificial leather based on the knitted fabric of the present invention includes the step of solvent-exchanging the polyurethane impregnated brushed knitted fabric in a coagulation liquid bath to form a polyurethane-filled brushed knitted fabric (step S40).

When the polyurethane impregnated brushed knit fabric formed in step S30 is deposited in a coagulation solution, dimethyl formamide, which is a solvent of the polyurethane solution of the polyurethane impregnated brushed knit, is eluted, and the solvent is exchanged to solidify the polyurethane as a solid structure.

The coagulation liquid contained in the coagulation liquid bath and coagulated by solvent exchange of the polyurethane solution of the polyurethane impregnated brushed knitted fabric uses water alone or a mixed coagulation liquid formed by mixing water and dimethyl formamide in a constant mixing ratio. By controlling the mixing ratio between the water of the mixed coagulation liquid and dimethyl formamide, the physical properties of the leather structure are arbitrarily adjusted.

When impregnated with a polyurethane impregnated brushed knit fabric in the coagulation liquid of the coagulation liquid tank as described above, dimethyl formamide, which is a solvent of the polyurethane solution infiltrated into the brushed layer of the polyurethane impregnated brushed knit fabric, is eluted and dissolved in the polyurethane solution. The polyurethane is solvent-exchanged and solidified into the leather structure, and the polyurethane solidified into the leather structure adheres to the brushed layer of the polyurethane-impregnated brushed knit fabric, thereby forming a polyurethane-filled brushed knit fabric in the form of artificial leather.

The method for producing artificial leather based on the knitted fabric of the present invention includes a step of dry drying the polyurethane filled brushed knitted fabric (step S50).

Specifically, the polyurethane-filled brushed knitted fabric which is solvent-exchanged in the step S40 to form an artificial leather is taken out of a coagulating solution tank, dried naturally, dried in an oven, or dried dry by hot air, etc. Artificial leather based on the knitted fabric of the present invention is produced by evaporating and removing the water and dimethyl formamide remaining on the surface.

Artificial leather based on the knitted fabric produced as described above is manufactured using a low-cost knitted sheet composed of general filament filaments and high-shrinkable filament fibers in general, the production is very easy and manufacturing cost is greatly reduced.

Claims (5)

(Correction) It is formed by raising the polyester monofilament long fiber part of both surfaces of the knitted sheet which consists of a triple structure of polyester monofilament long fiber of 0.5-1.0 denier on both surfaces, and a highly shrinkable polyester filament fiber in the center part. An artificial leather based on a knitted fabric consisting of a double-sided brushed knitted fabric which is to be wet impregnated into a polyurethane solution, solvent exchanged under a coagulating solution, and dried and dried. (Correction) The artificial leather according to claim 1, wherein the shortness of the highly shrinkable polyester filament fibers in the center portion of the knitted sheet is 50 to 300 denier. (Correction) knitting a surface of 0.5 to 1.0 denier polyester monofilament long fibers, the central portion of the high-shrinkage polyester filament fibers in a triple structure to form a knitted sheet; Brushing both surfaces of the knitted sheet to form a double-sided brushed knit fabric having a brushed layer of constant thickness; Impregnating said double-sided brushed knit fabric in a polyurethane solution to form a polyurethane impregnated brushed knit fabric; Solvent-exchanging the polyurethane impregnated brushed knitted fabric under a coagulating solution to form a polyurethane-filled brushed knitted fabric; And Method of manufacturing artificial leather based on the knitted fabric comprising the step of dry drying the polyurethane filled brushed knitted fabric. (Correction) The method of claim 3, wherein the forming of the double-sided brushed knitted fabric is performed by raising the knitted sheet between a pair of brushed rollers for raising the brush having a constant density to brush the both surfaces of the knitted sheet. A method for producing artificial leather based on a knit fabric, characterized in that. (Correction) The artificial leather based on knitted fabric according to claim 3, wherein the coagulating liquid used in the step of forming the polyurethane-filled brushed knitted fabric is water or a mixed liquid of water and dimethyl formamide (DMF). Method of preparation.