KR900005002B1 - Manufacturing process of nonwoven fabric felt - Google Patents

Abstract

A process for mfg. a long staple nonwoven fabric felt comprises spinning two component conjugated yarn having a reciprocal parallel sections, passing the yarn through the enclosed tube of 1.5-4.5 bar of gas stream to form a long staple web, needlepunching the web to be 0.23-0.32 g/cm3, and slack-heating it in the hot bath. The conjugated yarn comprises a high shrinkable copolymeric polyester resin contg. 85-95 mol.% of polyethyleneterephthalate and a polyamide resin. The felt has a good tensile and exfoliation strength, and is used in the mfr. of artificial leathers.

Description

Manufacturing method of long fiber nonwoven felt (FELT)

1 is an illustration of an apparatus used in the present invention.

Fig. 2 (a) is a partially enlarged view of the long fiber nonwoven web before division and shrinkage treatment.

(b) is a single yarn enlarged cross-sectional view of a long fiber nonwoven web before division and shrinkage treatment.

(A) of FIG. 3 is a partial enlarged view of the long fiber nonwoven felt after division and shrinkage treatment.

(b) is a single enlarged cross-sectional view of the ultrafine long fibers after split and shrink treatment.

* Explanation of symbols for main parts of the drawings

1,1 ': Melting device of each component polymer 2: Spin Block

3: sealed tube 3 ': air flow inlet

4: Long Fiber Web 5: Conveyor Net

6: needle punching 7: relaxation heat treatment bath

8: Winding machine 9: Opening device

The present invention relates to a method for producing a long-fiber nonwoven felt for manufacturing artificial leather, especially suede artificial leather, having excellent physical properties by using a composite spinning technique and a nonwoven fabric manufacturing technique. It is about a method. Background Art Conventionally, a number of methods using woven fabrics, knitted fabrics, nonwoven fabrics, etc. have been proposed in the manufacture of artificial leather, in particular, suede artificial leather.

The method of using woven fabrics or knitted fabrics is a method of directly raising the fiber structure formed by the weaving and knitting process or buffing after processing a polymer elastic body such as polyurethane to the napped structure. There is a method of obtaining a target object by impregnating or applying an elastic polymer material or a solution or emulsion of a polymer material mainly composed of the fibrous material in which the fiber is three-dimensional, and a single fiber composed of two or more kinds of different solubility polymer materials The method of obtaining the target object by dissolving the fibrous material three-dimensionalized by utilization needle punching at least 1 type of polymeric material soluble solvent, and partially dissolving it is used. However, each of these methods has advantages and disadvantages.

For example, the method using woven fabrics, knitted fabrics or ordinary short fibers can provide products with a flexible blend, but it is difficult to obtain finely fibrous materials, and the appearance after raising and buffing in suede artificial leather is extremely poor. Due to its low functionality and physical properties, it is practically difficult to obtain high quality products. When using short fibers composed of two or more different solubility polymer materials, it is difficult to use high density fibrous materials to obtain flexible mixing. There is a problem in that the manufacturing cost is increased because at least one component of the manufacturing apparatus for manufacturing the ultrafine fibers and the three-dimensionalized fibrous material must be dissolved in the soluble solvent of the high molecular material, and the manufacturing cost is increased. The needle pattern is high due to the high total needle density applied. By being spoiled, and the appearance and the needle track (Needle track) occurs, the repeated several times brushed processing, such as buffing processing to remove them there is a problem that had reduced functionality and the physical property.

The present invention solves the problems of the prior art as described above will be described in detail below.

A first component and a polycondensation copolymer made of a highly shrinkable co-polyester thermoplastic synthetic resin using two types of fiber-forming thermoplastic resins which are completely incompatible and non-bonding, and wherein 85 to 95 mol percent of the components are polyethylene terephthalate. A bicomponent composite yarn having an alternating parallel type cross section is manufactured using a second component made of an amide thermoplastic synthetic resin, and the bicomponent composite yarn having passed through the detention apparatus 2 has an air pressure of 1.5 bar (BAR). After passing through a closed tube (3) of -4.5 bar (BAR) and forming a long fiber web (WEB) (4) with the carding machine (9), the density of the felt was 0.23 g / cm 3-0.32 g / cm 3 After needle punching in the needle punching machine 6, the felt is divided and shrunk in the boiling water of the relaxation heat treatment bath 7 so that the long-fiber single yarn denier after treatment is ultrafine fibers of 0.01 denier to 0.1 denier and the number of felt areas It is a manufacturing method of long fiber ultrafine nonwoven high density felt with shrinkage of 30-50%.

In FIG. 1, 1, 1 'is a melting apparatus of a two-component polymer, 3' is an air inlet, 5 is a conveyor net, and 8 is a felt winding machine.

The two fiber-forming thermoplastic resins used in the present invention must use synthetic resins that are completely incompatible and have no mutual bonding force, and one of them must be a component having high shrinkability.

If a thermoplastic synthetic resin having compatibility and bonding strength is used, there is no problem in the composite spinning and needle punching processes in the manufacturing process, but it is difficult to achieve the miniaturization of the fibers in the splitting process, and thus it is difficult to achieve the object of the present invention.

In addition, when one component of the used component polymer is not highly shrinkable, fine fibers can be obtained during the split shrinkage process, but the density of the felt after shrinkage is low so that the high density felt, which is the intended purpose of the present invention, cannot be obtained.

Therefore, in the present invention, the first component of the two fiber-forming thermoplastic synthetic resins is made of a high shrinkage hollow core polyester thermoplastic synthetic resin composed of polyethylene terephthalate with 85 mol percent to 95 mol percent of the components. The range is 87 mole percent or more and 95 mole percent or less.

In addition, the component ratio of the electric two-component composite yarn forming an alternating parallel type cross section is preferably in the range of 80: 20-60: 40 for the ratio of the first component to the second component. The component ratio of 70:30 is the most preferable in consideration of the fineness and the high density of the felt after the uniformity and the split shrinkage treatment.

In the present invention, the two-component composite yarn needs to pass through a hermetic tube having a pressure of 1.5 bar-4.5 bar when forming a web on the conveyor net 5 of FIG.

If the air flow pressure is 1.5 bar or less, the inventors have tested the multifilament group that passed through the sealed tube when the carding machine is opened. It is the main cause of deterioration of operability. In view of good openness and operability, the most suitable air pressure is in the range of 1.7 bar to 4.3 bar.

In addition, the electric long-fiber web formed in the present invention requires setting needle punching conditions so that the density of the felt after needle punching is 0.23 g / cm 3 -0.32 g / cm 3. In general, high density felt refers to the density of the felt after shrinkage is 0.35 g / cm 3 or more.

If the needle punching condition is set so that the density of felt after needle punching is 0.23g / cm3 or less, the density of three-dimensional entanglement between fibers is insufficient, so that the felt density after heat shrinkage treatment cannot be made high and suede artificial leather is manufactured. The quality of the product after raising the buff will be reduced.

In addition, when needle punching conditions are set so that the density of felt after needle punching is 0.32g / cm3 or more, the friction between the long fibers and the needles during needle punching is severe, which causes the long fibers to be broken and not only reduce the felting effect. Severe damage to the product.

The condition of needle punching that does not cause good three-dimensional entanglement density and long fiber breakage is preferably set to needle punching conditions such that the density of felt after needle punching is in the range of 0.27 g / cm 3 -0.3 g / cm 3.

As the type of needle that can further effect the long fiber nonwoven fabric of the present invention, a die pressed type is more advantageous than a convention type, and the size of the needle is 2 ^b rather than 3 ^b / 3 ^E. / 2 ^E or 1 ^b / 1 ^E is much more suitable (b: barb, E: Edge) The three-dimensional entangled long-fiber nonwoven felt produced by the method described above in the present invention is a long-fiber single yarn denier by treating in hot water Is 0.01 denier to 0.1 denier and the density of felt is increased to 30-50 percent, which is due to the interaction of each component polymer constituting the alternating parallel type cross section. Highly shrinkable co-polyester thermoplastic synthetic resins with percent or less of polyethylene terephthalate, and the second component is composed of polyamide-based thermoplastic synthetic resins. The inherent shrinkage difference between the polymers is significantly different, and the electric two-component composite yarns passed through the detention during the weaving process are completely stretched by the pressure of the air stream, but they are not heat-set by heat as in the normal filament stretching process. The internal shrinkage stress received during the stretching is retained as it is.

Therefore, after the long fiber web is formed, the needle punching process maintains three-dimensional entanglement as shown in FIG. By dividing and shrinking, as shown in FIG. 3B, a long fiber ultrafine nonwoven fabric high density felt is spun naturally by the shrinkage difference of each component, which is microfiber and at the same time high density.

The long-fiber ultrafine nonwoven high density felt produced by the method of the present invention is easier to control the weight and thickness than the felt produced using short fibers in the manufacture of felt, and the manufacturing equipment is much simpler, which has a great effect on the texture of manufacturing cost. You can get it.

In other words, when the felt is manufactured using short fibers, a short fiber manufacturing process such as spinning, stretching, crimping and cutting processes, and a felt manufacturing process such as opening, carding, and needle punching are required. On the other hand, the method according to the present invention can form the long fiber web after the spinning process, and then directly manufacture the felt by needle punching, thereby greatly shortening the manufacturing process.

In addition, since it is a high-density felt using long fiber microfiber, tensile strength (including cross direction and machine direction) is better and uniform than felt manufactured using short fiber or short fiber microfiber, and it has excellent physical and mechanical properties such as peel strength. By using this, suede artificial leather is manufactured by raising, buffing, etc., high-quality products with excellent appearance and excellent functionality and practicality can be obtained.

EXAMPLE

The ultimate viscosity is 0.65 (measured by OCP solvent at 25 ° C.) and 90 mole percent of its constituents are composed of polyethylene terephthalate, a highly shrinkable copolyester thermoplastic synthetic resin as a first component, and a relative viscosity of 2.50 (H at 25 ° C.). ₂ SO ₄ solvent) and a polyamide-based thermoplastic synthetic resin as a second component was spun at 290 ℃ to form an alternating parallel cross-section as shown in Fig. 2a (the ratio of the components of the first component and the second component is 7: 3) The long-fiber Op is formed so that the long-fiber single yarn denier becomes 1 denier by passing through a sealed tube with an air flow pressure of 2.5 bar, and then using a 2 barb / 2 edge standard die press needle (manufactured by Singer). Needle punching was carried out such that the weight after needle punching was 800 g / m 2, the thickness was also 2.9 mm, and the density was 0.27 g / cm 3. Subsequently, the shrinkage treatment was performed in a hot water bath at 100 ° C. to prepare a long fiber ultra-fine nonwoven high density felt having an area shrinkage of 40% and a long fiber single yarn denier of 0.03 denier-0.09 denier felt having a density of 0.39 g / cm 3. . The high-density felt prepared in this way was impregnated with DMF solution of 30% polyurethane, coagulated, dried, brushed, and buffed to manufacture suede artificial leather, and the results of comparing with the quality of natural suede are shown in Table 1.

TABLE 1

Claims (1)

Two types of fiber-forming thermoplastic resins, which are completely incompatible with each other and have no bonding strength, are used. The first component is a highly shrinkable co-polyester resin in which at least 85 mol% and at most 95 mol% of the components are polyethylene terephthalate. The second component is a polyamide-based resin and spun a bicomponent composite yarn having an alternating parallel cross section, and then passes through a closed tube having an air pressure of 1.5-4.5 bar (BAR) to form a long fiber web ( WEB), and then the web is needle punched to a density of 0.23 g / cm 3-0.32 g / cm 3, and then passed through the hot water in a binocular state for producing a long fiber nonwoven felt.

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