KR100680382B1 - Synthetic Fiber Spunbond Nonwoven Fabric - Google Patents

Abstract

The present invention relates to a synthetic fiber spunbond nonwoven fabric, and the present invention provides a high quality spunbond nonwoven fabric having a CV% of 10 or less and a machine direction / width direction (MD / CD) strength ratio of 2.0 or less. Is produced by maximizing the opening efficiency and making the distribution of filaments uniform throughout.

Description

Synthetic fiber spun-bonded non-woven fabric             

1 is a view schematically showing a spunbond nonwoven fabric manufacturing apparatus according to an embodiment of the present invention.

Figure 2 is a schematic view showing a spunbond nonwoven fabric manufacturing apparatus according to the conventional method.

Brief description of the symbols for the main parts of the drawings

11, 11 ': spinneret 12, 12': cooling means

13, 13 ': high pressure ejector 14, 14': extension tube

15, 15 ': Opening means 15a, 15a': High voltage generator (HVG)

16, 16 ': Collision plate or deflector 17: Net conveyor

18: calendar roll 19: winder

Y, Y ': Filament Bundle

The present invention relates to a synthetic fiber spunbond nonwoven fabric, and more particularly, to a new synthetic fiber spunbond nonwoven fabric having a high uniformity and a low strength ratio, and a method of manufacturing the same.

Nonwoven fabrics are manufactured by various methods such as spunbond method, spunlace method and meltblown method using long fiber, short fiber form and various materials. Among them, the long fiber nonwoven fabric produced by the spunbond method is widely used for industrial purposes because it can produce a strong and thin product compared to the general nonwoven fabric and short fiber nonwoven fabric produced by other methods. In general, spunbond nonwoven fabrics produce nonwoven fabrics by spinning filament fibers in the same manner as the conventional synthetic fiber spinning process, and thus the production and use of spunbond nonwoven fabrics continue to expand.

Conventionally, the spunbond synthetic fiber nonwoven fabric is a high-pressure air ejector (3) after the multifilament bundle (Y) spun in the spinneret (1) is cooled and solidified in the cooling chamber (2) as shown in FIG. It is laminated in the form of a web on the moving net conveyor 7 after being continuously drawn through. By using the calender roll 8 in which various embossed patterns of irregularities are carved into the laminated web, heat and pressure are simultaneously applied to form an embossed nonwoven fabric which gives physical characteristics of a certain thickness or has protrusions on the surface. It is manufactured by making a needle punch nonwoven fabric in which a nonwoven fabric is produced by interweaving fibers on the needle surface projection by rapidly reciprocating the needle in the vertical direction of the web using a metal needle, and then twisting it in the winding machine 9 come.

In the prior art, attempts have been made in making the spunbond nonwoven fabric to have a uniform distribution of the web formed by forming the filament bundle Y onto a conventional net conveyor 7 so as to be made into a web.

For example, US Pat. No. 2,736,676 describes a manufacturing process for mats or sheets of yarn or strands or glass strands made of a variety of materials. Although the use of a deflector surface is described, this method may show a loop shape when the filaments are stacked on the net conveyor due to the twisting effect, and the product may have poor uniformity and cause inadequate width control. Is holding.

U. S. Patent No. 247,874 also describes a method of causing a fluid jet device to collide on the same plane as the filament axis before and after the deflector surface. However, this method also has disadvantages such as poor uniformity of the web laminated on the net conveyor and inadequate width control.

U.S. Patent No. 3,293,587 describes a method for improving uniformity by using a device in which a fixed deflector and a vibrating deflartor are combined together and adjusting angles, vibration frequencies, amplitudes, and the like. However, this also occurs when the web is loaded on the net conveyor after collision at the deflector, when the opening is poor or when the filaments are accumulated on only one side, so that the shape of the furrow in the longitudinal direction occurs. (So-called "bone development") is a clear appearance of the disadvantage that the overall uniformity is poor.

Therefore, the main object of the present invention is to provide a new synthetic fiber spunbond nonwoven fabric having high uniformity and low strength ratio.

Another object of the present invention is to provide a method for producing a spunbond nonwoven fabric having the above characteristics.

It is still another object of the present invention to provide an apparatus suitable for carrying out the above-described manufacturing method.

According to the present invention which achieves the object of the above object, in the synthetic fiber spunbond nonwoven fabric, the CV% is 10 or less, the polyester spunbond characterized in that the machine direction / width direction (MD / CD) strength ratio is 2.0 or less Nonwovens are provided.

In addition, according to the present invention, the molten polymer is extruded from the spinneret, and the filament bundle cooled and solidified by the cooling means is stretched by high pressure air by passing through a drawing tube, and electric opening is performed by charging and diffusion by applying a high voltage. In forming a web by colliding with a collision plate and spreading it on a net conveyor under suction, and combining the conveyed web to manufacture a synthetic fiber spunbond nonwoven fabric,
Extruding and freezing and stretching the first filament bundle through the first spinneret and then at the first opening means and opening, and extruding and freezing and stretching the second filament bundle through the second spinneret and then Open in two opening means; The opened filament bundle is collided with the colliding plate which is inclined downward in the opposite direction of the net conveyor and spreads on the net conveyor, and the opened second filament bundle is collided downward in the same direction as the traveling direction of the net conveyor. Provided is a method for producing a synthetic fiber spunbond nonwoven fabric which is characterized in that it impinges on a plate and is spread over a net conveyor to form a web.

In addition, according to the present invention, the first spinneret and the second spinneret; Open cooling means; A first stretched tube for stretching the first filament bundles formed through the first spinneret and cooled and solidified, and a second stretched tube for stretching the second filament bundles formed and cooled through the second spinneret; First and second opening means for opening the stretched first and second filament bundles by applying a high voltage, respectively; A first colliding plate positioned below the first opening means and inclined downward in a direction opposite to the traveling direction of the net conveyor and a second colliding plate inclined downward in the same direction as the traveling direction of the conveying conveyor; Net conveyor means for conveying while stacking the impacted fibers to form a web; There is provided an apparatus for producing a synthetic fiber spunbond nonwoven fabric comprising means for joining a web and winding means.

Hereinafter, the present invention will be described in more detail with reference to the accompanying drawings.

1 schematically shows an example of a preferred apparatus for producing a synthetic fiber spunbond nonwoven fabric according to the present invention. The synthetic fiber spunbond nonwoven fabric shown is shown in the first and second spinnerets 11 and 11 ', open type cooling means 12 and 12', first and second high pressure ejectors 13 and 13 ', and First and second stretch tubes 14 and 14 ', first and second opening means 15 and 15', first and second impingement plates 16 and 16 ', net conveyors 17 and 17', The calender roll 18 and the winder 19 are provided.

The first filament bundle Y has a first spinneret 11, an open type cooling means 12, a first high pressure ejector 13, a first stretch pipe 14, a first opening means 15 and a first Falling on the net conveyor 17 in a direction opposite to the traveling direction through the first row of radiation devices made of the impingement plate 16; The second filament bundle Y 'includes a second spinneret 11', an open type cooling means 12 ', a second high pressure ejector 13', a second stretch tube 14 ', and a second opening means ( 15 ') and second impingement plate 16' are formed on the net conveyor 17 by falling in the same direction as the propagation direction on the net conveyor 17 through the spinning device.

At this time, the cooling section passes through a cooling section for cooling the high-temperature filament bundles Y and Y 'discharged through the detention unit 1, and this cooling section is preferably stabilized by external air flow by performing an open cooling method. It is effective to allow natural cooling.

In addition, the filament bundle drawn through the high-pressure ejector and the stretching tube has a high-pressure generator 15a in the orthogonal direction to the opening means 15 and 15 'in order to give an opening effect in which the respective filament strands are evenly dispersed without agglomeration. 15a ') is attached to the electric opening. According to the electric opening, the filament strands of the filament bundles passing through the high-pressure ejector 13, 13 'at high speed are pushed together by an electric force by the high-voltage electricity to maximize the opening effect. In other words, the electric repulsion force is increased to have an effect of improving the diffusion force. Preferably, the large voltage applied to the carding means is 10 to 50 kV, more preferably 20 to 40 kV. If the large voltage is less than 10 kV, it is difficult to expect the diffusion force due to accurate repulsion, and if it exceeds 50 kW, a short circuit is likely to occur, and thus there is a risk of fire.

In addition, it is suitable that the first opening means 15 and the second opening means 15 'have a short interval (pitch), preferably 40 to 400 mm, more preferably 80 to 200 mm. This is to assist in solving the bone development phenomenon caused by the wide pitch interval between the opening means when the filaments are stacked on the net conveyor 17 under suction. If the pitch interval between the opening means is less than 40mm, air disturbance occurs due to the aerodynamic interference between the opening means, which adversely affects the distribution of the web, and if it exceeds 400mm, the pitch interval is too wide. It is not preferable because the possession to reproduce the bone development phenomenon is rich.

The filaments opened in a uniformly distributed state by the electric openings hit the impact plates 16 and 16 'which are inclined downward at a predetermined angle immediately below the opening means 15 and 15', and then the net conveyor 17 under suction. Laminate while spreading evenly on the phase.

In order to give a soft collision effect when the filaments distributed evenly by the electric seam collide with the collision plate, the collision plate is inclined downward while maintaining a constant angle, but the first collision plate 16 is the net conveyor 17. The second collision plate 16 'is inclined downward in a direction opposite to the inclination direction of the first collision plate 16, and the collision position of the filament is It is desirable to be on top. If the collision plate is inclined downward and the filaments collide with the collision plate, the collision position becomes the upper part of the collision plate, and the sliding effect is softened by moving down on the traveling net conveyor. It will be placed in position so that the filaments can be uniformly distributed on the net conveyor.

The web thus formed is loaded on a conveying conveyor to a coupling means 18 such as a calender roll, a needle punching machine, a water punching machine, and the like, which is made of a nonwoven fabric, and then wound on a winding machine 19 to be shipped in a roll state.

Synthetic fibers usable for producing nonwovens according to the present invention are all kinds of synthetic fibers known for the manufacture of spunbond nonwovens, with synthetic fibers being particularly preferred among them.

According to the present invention as described above, when the web is laminated, it maximizes the electric opening efficiency by the high voltage generator, and when it collides with the collision plates 16 and 16 'and is stacked on the net conveyor 17, Even when manufacturing the product, there is no valley in the longitudinal direction, the overall uniformity is excellent, the strength is strong in the longitudinal direction and the width direction, and there is no difference between these strengths, which improves performance such as strong stability and dimensional stability in both directions. Can be achieved.

In terms of quantified values, the nonwoven fabric of the present invention, regardless of weight, has a uniform distribution of CV% 10 or less and excellent strength stability and dimensional stability of machine direction / width direction (MD / CD) strength ratio of 2.0 or less. In particular, the present invention is very useful for producing high quality low weight nonwoven fabrics because the above properties are satisfied even at a low weight of less than 30 g / m 2. Of course, according to the present invention, even when producing a heavy product of 30g / ㎡ or more, it is possible to produce a high-quality nonwoven fabric having a uniform distribution and excellent strength stability and dimensional stability.

Features and other advantages of the present invention as described above will become more apparent from the following examples. However, it should be understood that the present invention is not limited to the following examples.

<Example 1>

In the apparatus of FIG. 1, a polyester spunbond nonwoven fabric was prepared under the following conditions.

First, polyethylene terephthalate having an intrinsic viscosity (IV) of 0.645 was melted and extruded through the first and second spinnerets 11 and 11 'each having a capillary size of 0.3 mm and a capillary number of 38 at a spinning temperature of 280 ° C. . The first and second filament bundles (Y, Y ') extruded through the spinneret are cooled and solidified by cooling air in an ambient atmosphere in the open type cooling chambers (12, 12'), respectively, and then the high pressure air ejector (13, 13 ') and the extending pipes 14 and 14' to draw, and opened and opened the opening means 15 and 15 '. At this time, a high voltage of 15 kW was applied to the filament bundle passing through the carding means 15 and 15 'to charge and diffuse the filaments in the carding means. The pitch pitch between the first opening means 15 and the second opening means 15 'was 50 mm.

Next, the first filaments Y charged and diffused in the first opening means 15 collide with the upper part of the inclined first colliding plate 16 and slide to fall to the net conveyor 17 under suction, The second filaments Y 'charged and diffused in the second opening means 15' collide with the upper part of the inclined second colliding plate 16 'and slip and fall to the net conveyor 17 under suction. Laminated in web form on net conveyor. The web laminated on the net conveyor 17 was fed to the calender roll 18 to which the embossing was given, bonded and wound to prepare a polyester spunbond nonwoven fabric having a weight of 25 g / m 2. The distribution (CV%) and MD and CD tensile strengths of the prepared nonwoven fabrics were measured and the results are shown in Table 1 below.

At this time, the distribution ratio (CV%) of the nonwoven fabric was taken from 20 nonwoven fabric samples having a size of 100 cm x 100 cm in width x length, and then the respective weights and thicknesses (thicknesses) were measured. % Was calculated and it was judged as being excellent when average CV% value was less than 8.0, good in 8-10, and bad in 10 or more.

<Examples 2 to 4 and Comparative Examples 1 to 2>

Example 1 except that the voltage applied to the filament bundle passing through the opening means and the pitch between the first opening means 15 and the second opening means 15 'are changed as shown in Table 1. The same procedure was repeated.

 Comparative Example 3

The same procedure as in Example 1 was repeated except that the device of FIG. 1 was adjusted such that the opened filament collided with the bottom of the impingement plates 16, 16 '.

 <Comparative Example 4>

The same procedure as in Example 1 was repeated except that the apparatus of FIG. 1 with the impingement plates 16 and 16 'removed was used.

division Cooling method Large voltage (㎸) Pitch (mm) Collision Plate Collision Position Weight (g / ㎡) Distribution (CV%) Tensile Strength (㎏ / 5㎝) Strong ratio (MD / CD) MD CD Example 1 Open 15 50 Top 25 Great 5.3 2.8 1.9 Example 2 Open 30 50 Top 25 Great 5.6 3.5 1.6 Example 3 Open 45 50 Top 25 Great 5.2 3.1 1.7 Example 4 Open 30 300 Top 25 Great 5.4 3.2 1.7 Comparative Example 1 Open 8 50 Top 25 Bad 4.3 1.2 3.6 Comparative Example 2 Open 15 420 Top 25 Bad 3.7 1.0 3.7 Comparative Example 3 Open 15 50 bottom 25 Bad 5.5 2.3 2.4 Comparative Example 4 Open 15 50 No collision 25 Bad 2.6 0.6 4.3

As can be seen from the results of Table 1, according to the present invention, the bone development phenomenon is eliminated and the opening efficiency is maximized when the web is laminated, so that the uniform distribution is obtained. This makes it possible to provide high quality spunbond nonwovens of high commercial value and little difference therebetween.

Claims (9)

The molten polymer is extruded from the spinneret, and the filament bundles cooled and solidified by the cooling means are stretched through high-strength air through a drawing tube, and an electric voltage is applied by charging and diffusion by applying a high voltage, and then impinges on the collision plate. In the process of forming a web by spreading on a net conveyor under suction and combining the conveyed web to produce a synthetic fiber spunbond nonwoven fabric, Extruding and freezing and stretching the first filament bundle through the first spinneret and then at the first opening means and opening, and extruding and freezing and stretching the second filament bundle through the second spinneret and then Open in two opening means; The opened filament bundle is collided with the colliding plate which is inclined downward in the opposite direction of the net conveyor and spreads on the net conveyor, and the opened second filament bundle is collided downward in the same direction as the traveling direction of the net conveyor. A method for producing a synthetic fiber spunbond nonwoven fabric, which is formed by impinging on a plate and scattering on a net conveyor to form a web. 2. The method of claim 1, wherein the first and second filament bundles are cooled and solidified by an open type cooling method. The spunbond nonwoven fabric according to claim 1, wherein the high voltage applied to the first opening means for opening the first filament bundle and the second opening means for opening the second filament bundle is 10 to 50 kPa, respectively. Manufacturing method. The method of manufacturing a spunbonded nonwoven fabric as claimed in claim 1, wherein a distance (pitch) between said first opening means and said second opening means is 40 to 400 mm. The method of manufacturing a spunbonded nonwoven fabric as claimed in claim 1, wherein a calendering method, a needle punching method, or a water punching method are used to join the web. The method for producing a spunbond nonwoven fabric according to any one of claims 1 to 5, wherein the synthetic fiber is a polyester fiber. A spunbonded nonwoven fabric having a synthetic fiber spunbond nonwoven fabric having a CV% of 10 or less and a machine direction / width direction (MD / CD) strength ratio of 2.0 or less. The spunbond nonwoven fabric of claim 7, wherein the weight is less than 30 g / m 2. A spunbonded nonwoven fabric as claimed in claim 7 or 8, wherein said synthetic fibers are polyester fibers.

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