KR870002085B1 - Manufacturing method of synthetic leather - Google Patents

Abstract

The invention employs a sea-and-island type blended fiber that has the square shrinkage ratio of 10-50% in being made into nonwoven fabric and comprises an island part polymer for very fine fibers of 0.001-0.5 denier and a sea part polymer, whose heat fixation temperature is lower by 10-80 deg.C than the former, for the binder of the convergent fine fibers. The fine island fiber is made of polyethylene terephthalate or nylon-6, and the sea polymer is of polystyrene, polyethylene or polyethylene glycole.

Description

Manufacturing method of artificial leather

The present invention relates to a method for producing artificial leather having a dense structure and excellent steel and elongation.

More specifically, in the present invention, the present invention uses a microcomponent fiber as a microcomponent fiber component having a single component fine fiber having a single yarn fineness of 0.001 to 0.5 denier, and a sea component polymer having a heat setting temperature of 10 ° C. to 80 ° C. lower than a ceramic component. By using a special island-in-the-sea latent crimped fiber, the present invention relates to a method for manufacturing artificial leather having a higher density and improved strength and elongation compared to conventional artificial leather by only a simpler process.

In Japanese Patent Publication No. 49-100375, a method of manufacturing artificial leather, a needle punched nonwoven fabric is used.

1) Process to give water-soluble polymer

2) Extraction and Removal of Sea Component Polymers

3) Compression fixation of bubbles using heat and pressure

4) Process to give a polymer elastomer

5) Artificial leather is manufactured through the process of extracting and removing the water-soluble polymer, and US Patent No. 4,206,257 manufactures artificial leather by proceeding the above process procedure in the order of 1) 3) 4) 5) 2).

The characteristic of the present invention is that artificial density improved 20 to 40% compared to conventional artificial leather by using only the processes of 3) 4) and 2) without requiring the processes of 1) and 5) described above using a special island-in-the-sea composite fiber. It is to be able to manufacture leather.

The special island-in-the-sea composite fiber used in the present invention uses polyethylene terephthalate or nylon-6 as the island component, and polyethylene, polystyrene or polyester as the sea component is modified and used to form a continuous filament and have stretchability. .

That is, continuous fine filament of the island component polymer is present in the fibrillated phase in the sea component by carrying out the active compound spinning or brand spinning through the special detention apparatus together with the above-mentioned sea component polymer such as polyethylene terephthalate and nylon-6. Special islands-in-sea composite fiber can be obtained.

In the present invention, low-density polyethylene, polystyrene or polyester is used as a sea component polymer by copolymerizing or branding with one compound of polyethylene glycol, 2-ethylhexyl acrylate, epicpic acid or dimethyl sulfoisophthalate.

The composite fiber made in this way has latent crimping ability in proper drawing process and mechanical crimping process, and then, if hot water or dry heat treatment is performed, the area shrinks by about 10-50%, contributing to the densification of the structure.

On the other hand, the polyurethane used in the present invention is as follows.

For impregnation of non-woven fabrics is an ester-ether copolymer, a soft block of polycaprolactone diol and polytetramethylene ether glycol, a hard block of diphenylmethane 4,4′-diisocyanate and a diol- or diamine-based chain extender. As a result, a 25% dimethylformumamide solution was prepared and used.

For the following microporous insects, a one-component linear polyurethane elastomer composed of 1000 parts of polycaprolactone diol, 250 parts of difelnylmethane 4,4′-isocyanate, 60 parts of ethylene glycol, and 80 parts of butanediol is used to obtain 1-5 μ after wet processing. It is possible to form a porous layer film in which numerous fine pores are present.

On the other hand, for the surface layer, both ester and ether type can be used, but in the upper type artificial leather of the present invention, the ether type using polytetramethylene ether glycol was effective in terms of physical properties such as hydrolysis resistance.

Next will be described in detail with respect to the manufacturing method of the leather-like sheet material using the ultrafine composite fiber and the polyurethane elastic body of the present invention.

Web was fabricated by carding 3d, 51mm composite fiber staples in a cloth or metallic card machine, and cross-wrapped it to a suitable weight, and then needle needle machine with needle density of 2000 times / cm2 or more. Punch.

In this case, in the case of the nonwoven fabric of 600g / ㎡ in weight, the thickness has a structure of three-dimensional entangled fibers of about 3mm.

When shrinked in hot water, the area shrinks by 10-50% and the density rises to about 0.3g / C㎥, and when it is compressed while giving a constant gap with heat and pressure of 100-200 ℃, the thickness decreases to be 0.4-0.6g / It has a density of about C m 3, and when the polyurethane elastomer is filled therein, the density becomes 0.6-0.7 g / C m 3.

Next, the removal of the sea component polymer, which acted as a binder, resulted in a density of 0.4-0.5 g / Cm3 of the leather-like sheet, which has a much more dense structure than the density of 0.3-0.4g / Cm3 of the conventional artificial leather. do.

This will be described in detail for each process as follows.

Shrink and heat-set the needle-punched nonwoven fabric made above to make the surface uniform, and dense the interweaving structure of the fiber.The above-mentioned wet impregnated polyurethane elastomer is diluted to an appropriate viscosity, impregnated, and then solidified in water for 10 minutes, and then heated to 50 ° C The solvent dimethyl formamide is completely washed off with hot water.

Next, the sea component polymer is completely removed from the appropriate solvent of the sea component, and the fiber is microfiberized, and then, lightly buffed the surface of the wool with sander paper, thereby obtaining a leather-like sheet having smooth evenly distributed on the surface.

However, in general, when impregnated with polyurethane and the impregnating cloth is turned on with a slicing machine (Slicing machine) to the required thickness, it is advantageous in terms of quality and cost.

Next, if the above-mentioned polyurethane film for surface layer is laminated on leather-like sheet or wet coating of polyurethane for microporous layer first and then laminating the surface layer, the structure can be widely used for shoes, sports cars, bags and sundries. It is possible to obtain upper type artificial leather with less wrinkles and excellent mechanical properties.

Next, the application example of the present invention will be described in detail through examples.

Both% and parts refer to weight.

Example 1

Using 65 parts of polyethylene terephthalate as an ultrafine fiber component, 43 spun fibrils were formed in 35 parts of polystyrene containing 3% polyethylene glycol, and staple fibers having a fineness of 4 denier length of 51 mm were prepared.

Carting, cross-lapping and needle-biasing to make a non-woven fabric with a three-dimensional entanglement structure of weight 800g / ㎡, thickness 3.5㎜, shrink in boiling water and a suitable gap with a calender with a roll surface temperature of 100-200 ℃ When heat-setting, it becomes a dense nonwoven fabric with an apparent density of 0.5g / Cm3.

It is charged with an ester-ether copolymerized polyurethane such that the fiber / Pu is 78/25.

Next, dividing the thickness in two and removing the sea component in perchloroethylene yields a dense and uniform leather sheet having an apparent density of 0.484 g / Cm 3.

The polycaprolactone diol-based wet polyurethane is coated on it to form a microporous layer, and laminating a dry surface layer having a thickness of 50μ becomes an upper type artificial leather.

In Table 1, the physical properties of the leather-like sheet of Example 1 are shown together with the physical properties of Examples 2, 3, 4, and conventional products and natural leather.

In Table 1, it can be seen that the leather-like sheet of the present invention is well complemented with the neatness of conventional products, such as having fine structure and excellent mechanical properties while maintaining flexibility and generating fine wrinkles when folded.

Example 2

60-6 parts of nylon-6 and 40 parts of polyethylene (containing 10 mol% of 2-ethylhexyl acrylate) are mixed and spun through special molds to form nylon-6 in polyethylene with about 300-500 fibrils. Was prepared and performed as in Example 1 below.

Extraction of polyethylene is easily eluted by repeated dipping and squeezing in hot toluene.

The apparent density of the obtained leather sheet was 0.494 g / Cm 3, which was very dense and excellent in mechanical properties.

Example 3

60 parts of nylon-6 was used as an ultrafine fiber component and 40 parts of polyester containing 10 mol% of dimethyl sulfoisophthalate were made as in Example 1 below.

Extraction of the ultrafine fiber concentrator component was performed by the general alkali weight loss processing method.

Example 4

60 parts of nylon-6 was used as an ultrafine fiber component, and 40 parts of polyester containing 10 mol% of adipic acid were used in the same manner as in Example 3 below.

TABLE 1

Properties of Leather Sheets

(What is denoted by * A × B indicates measured values in the longitudinal direction and the width direction, respectively.)

Claims (3)

(Correction) In the manufacture of artificial leather, seaweed polymer having single yarn fineness of 0.001-0.5 denier is made of microfiber component, and the sea component polymer whose heat setting temperature is about 10 ~ 80 ℃ lower than that of microfiber component A method for producing artificial leather, characterized by using an island-in-the-sea composite fiber having a hydrothermal shrinkage of 10% to 50% in the nonwoven fabric, which is composed of an ultrafine fiber concentrator. (Correction) The process for producing artificial leather according to claim 1, wherein the ultrafine fiber component is polyethylene terephthalate or nylon-6. 2. The preparation of artificial leather according to claim 1, wherein the microfiber concentrator component is copolymerized or blended with a compound of polyethylene glycol, 2-ethylhexyl acrylate, adipic acid or dimethyl sulfophthalate of polystyrene, polyethylene or polyester. Way.