KR20140049956A - Melt blown fiber web and and producing method - Google Patents

Abstract

The present invention relates to a double-layer meltblown fiber web, which comprises a horizontal fiber layer (10) in which one side portion (F1) of meltblown microfine fibers (F) are laminated on each other in a transverse direction and a meltblown A vertical fiber layer 20 formed by extending the other side F2 of the microfine fibers F from the upper end of one side F1 of the meltblown microfine fibers F and stacking them in the longitudinal direction And the end F3 of the other side F2 of the meltblown microfine fibers F forms a curl in a shape of a downwardly curved double layered melt blown fiber It is about the web.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a meltblown fiber web having a double structure,

The present invention relates to a double layer meltblown fibrous web and a method for producing the same.

[0002] Meltblown fiber webs having staple fibers are known as "porous nonwoven webs including meltblown fibers and entangled staple fibers " What is claimed is: 1. A porous nonwoven web, wherein the meltblown fibers comprise a bimodal mixture of entangled microfiber and mesofiber, having at least about five times more microfibers than meshes, The meso fibers are webs that comprise at least about 30 weight percent of the meltblown fibers. "

U.S. Patent 4,118,531 filed on Nov. 7, 1977; Applicant: Monnesota Mining and Manufacturing Company recommends that microfibers having an average diameter of less than about 10 micrometers and calcein bulking fibers having at least 15% curl (i.e., staple fibers) are used in a ratio of from 9: 1 to 1: 9 Randomly blended and weaved together to publish a resilient, compressible fiberba structure with a loft of at least 30 cm ³ / g.

The present invention relates to a meltblown fiber web which is excellent in sound insulation and sound absorption characteristics against noise of a vehicle which is a problem in an internal combustion engine vehicle and can be relatively increased in energy efficiency of a vehicle due to its light weight per unit size, .

In addition, the present invention can increase the absorptive sound performance in the low frequency region (200 to 800 Hz) of the interior noise of the vehicle which the conventional sound absorbing material has not possessed. By adjusting the air permeability and the design factor, To a user (automobile company), and a method of manufacturing the same.

A dual-layer meltblown fibrous web according to an embodiment of the present invention includes a horizontal fiber layer (10) in which one side portion (F1) of meltblown microfine fibers (F)

Vertical fiber layer 20 formed on the other side portion F2 of the meltblown microfine fibers F while being extended upward from the upper end of one side portion F1 of the meltblown microfine fibers F and stacked on each other in the longitudinal direction. Including Layer),

The end portion F3 of the other side F2 of the meltblown microfine fibers F is characterized by forming a curl part F3 having a downwardly curved shape.

The meltblown fiber webs and the manufacturing methods thereof developed so far have limitations in producing a fibrous web having a lower density, a bulky structure and a dense internal structure, and the compressive elastic modulus and the sound absorption performance are also unsatisfactory. The object of the present invention is to overcome the limitations of the prior art. The inventor of the present invention, after many years of research, has developed a meltblown fibrous web having a density lower than that of conventional products, a bulky structure, a dense inner structure, The inventors of the present invention have invented a manufacturing method of the present invention. The meltblown fibrous web of the present invention is more bulky than an existing meltblown fibrous web, has excellent elasticity, has a dense inner structure, and can more easily control the characteristics of the product.

By using the present invention, it is possible to produce a meltblown fibrous web having a bulky structure, a more excellent elasticity, and a denser structure, and also can easily produce meltblown microfiber laminated forms with various changes The meltblown fiber web of various properties can be manufactured by a more convenient method by controlling the bonding strength, the twisted shape, the elasticity, the density and the volume of the fiber web, etc.

The effect of the present invention will be described in more detail. 1. A meltblown fibrous web having a density lower than that of the present invention and having a large volume and excellent resilience against compression can be provided to the market.

2. It is possible to provide the market with a meltblown fiber web which is superior in sound absorption performance and has a dense internal structure. Also, . It is possible to provide a meltblown fibrous web with a denser structure to the market, thereby improving the incendiary property.

3. Meltblown fiber webs of various density, elasticity and internal structure can be prepared by controlling the shape and lamination amount of the meltblown microfibers in the horizontal direction and the meltblown microfibers in the vertical direction. That is, it is possible to produce a meltblown fibrous web having various density, elasticity and internal structure by repeatedly laminating the meltblown microfine fibers in the horizontal direction and the meltblown microfibers in the vertical direction in an easy manner.

1 (a) and (b) are views showing the structure of a meltblown fiber web according to Example 1 of the present invention.
2 (a) and (b) are explanatory diagrams of a process for producing a meltblown fiber web according to Example 1 of the present invention and a meltblown fiber web according to the first embodiment.
3 is a detailed view of a process for producing a meltblown fiber web according to Example 1 of the present invention.
4 is an explanatory view of a process of manufacturing a meltblown fiber web according to Example 2 (including a staple pie bar) of the present invention and a meltblown fiber web according to Example 2. Fig.
5 is an explanatory view of a process of manufacturing a meltblown fiber web according to Example 3 (addition of foam parts) of the present invention.
6 is a flow diagram of a process for manufacturing a meltblown fibrous web according to one embodiment of the present invention.
7 is a schematic view of a comparative example 1 fiber web (only a transverse layer exists, no staple fiber) and a comparative example 2 fiber web (transverse layer and staple fiber).
Fig. 8 shows the results of tests of Example 1, Example 2, and Comparative Examples 1 and 2. Fig.
Fig. 9 shows results of sound absorption characteristics test of Example 1 and Comparative Example 1; Fig.
Fig. 10 shows results of sound absorption characteristics test of Example 2 and Comparative Example 2. Fig.

BEST MODE FOR CARRYING OUT THE INVENTION A double-layer melt blown fiber web and a method of manufacturing the same according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings. 1 (a) and (b) are explanatory diagrams of a process for producing a meltblown fiber web according to Example 1 of the present invention and FIGS. 2 FIG. 3 is a detailed view of a meltblown fiber web manufacturing process according to Example 1 of the present invention, and FIG. 4 is a cross-sectional view of a meltblown fiber web according to Example 2 (including a staple fiber) FIG. 5 is an explanatory view of a process of manufacturing a meltblown fiber web according to Example 3 (addition of a foam part) of the present invention, FIG. 6 Fig. 7 is a flow chart of a process for producing a meltblown fibrous web according to an embodiment of the present invention, Fig. 7 is a comparative example 1 fiber web (only a transverse layer exists, no staple fiber) 8 is a graph showing the results of tests of Example 1, Example 2, Comparative Examples 1 and 2, and FIG. 9 is a graph showing the results of comparison with Example 1 1 and the sound absorption property test results, Figure 10 is a Comparative Example 2, the sound-absorbing property test results as in Example 2.

As shown in FIGS. 1 to 10 (particularly, FIG. 1), a dual-layer meltblown fibrous web according to an embodiment of the present invention includes a horizontal fiber layer 10 and a vertical fiber layer 20 And a curl part (F3).

As shown in FIG. 1, the horizontal fiber layer 10 is formed by laminating one side portion F1 of the meltblown microfine fibers F with each other in a lateral direction. The vertical fiber layer 20 is formed in such a manner that the other side F2 of the meltblown microfine fibers F extends upwards from the upper end of the side F1 of the meltblown microfine fibers F, As shown in Fig. Meltblown Ultrafine Fibers F The end F3 of the other side F2 forms a curled portion F3 shaped like a downwardly curved shape.

As shown in FIG. 1B, the other side F2 of the meltblown microfine fibers F is preferably curled upwardly. Among the lower edge lines 11 of the horizontal fiber layer 10, the first edges 11 of the lower edge lines 11a (the reference line) in the direction in which the fibers are laid and the first array lines of the one side portions F2 of the meltblown microfine fibers F ( The transverse fiber layer average arrangement angle A formed by 10b) is preferably 0.001 to 45 degrees in the freely unfolded state or freely unfolded or covered with a covering fabric 30 and freely unfolded. .

As shown in Figure 1 to Figure 10 (particularly, Figure 1), in the double layer melt blown fibrous web according to an embodiment of the present invention, the fibers in the lower edge line 11 of the horizontal fiber layer 10 The vertical fiber layer average arrangement angle B formed by the lower edge line 11a (the reference line) and the second arrangement lines 20b of the other portions F2 of the meltblown microfibers F in the direction toward the direction of the jin direction is externally compressed. 45 to 45 ° with no load, freely unrolled or covered with a covering fabric (30), pulled upwards by 0.1 to 2 times the total thickness of the freely unrolled or unloaded fiber web. It is preferable that it is 90 degrees.

The reason for limiting the angle in the above is the horizontal fiber layer 10 It is intended to form a horizontal fiber layer concept close to the lower edge line (11a, reference line), and a vertical fiber layer (20, Vertical Fiber) Layer is intended to be formed in the concept of a vertical fibrous layer that is closer to the vertical than the lower edge line 11a (baseline) rather than horizontal . To increase the mass per unit volume, and if the thus formed was unknown test results that stability is enhanced and the intake sound insulation performance increase. If the angle of the transverse fiber layer 10 increases is 45 degrees when the horizontal layer concept beoteonamyeo the vertical fiber layer (20, Vertical Fiber Layer) angle of 45 degrees is small in number beyond the jikcheung concept.

As shown, in the double layer melt blown fibrous web according to an embodiment of the present invention, the crossing angle (C) of the horizontal fiber layer average array angle (A) and the vertical fiber layer average array angle (B) is an external compressive load. Free, unfolded or covered with covering fabric (30), free from external compressive loads, freely unrolled or pulled upwards by 0.1 to 2 times the total thickness of the unloaded fiber web , 1 to 89 ° is preferable. If it exceeds 89 degrees, there is a difficulty in the production method, and the bulkiness and sound absorbing and insulating characteristics are reduced.

As shown, in the double layer melt blown fibrous web according to an embodiment of the present invention, it is preferable to further include a staple fiber weaving the melt blown microfibers to each other. The meso fibers, which are staple fibers, include staple fibers such as olefin polypropylene (PP), polyethylene (PE), polyethylene terephthalate (PET), or amide nylon (Nylon). desirable.

As shown, in the double-layer melt blown fibrous web according to an embodiment of the present invention, the cover fabric (30, Covering Fabric) surrounding the melt-blown fibrous web, Covering fabric (30) Fabric) is preferably a nonwoven fabric consisting of spunbond fibers. The thickness ratio of the transverse fiber layer 10 and the longitudinal fiber layer 10 is not in an external compressive load and is in a freely unfolded state or in a freely unfolded state in which a covering fabric 30 is covered and not in an external compressive load or by a freely unfolded state or by an external force. With a pulled upwards of 0.1 to 2 times the overall thickness of the unloaded fiber web, a ratio of 1: 1 to 1: 9 is desirable in terms of vehicle manufacturer design requirements, sound absorbing and insulating properties, and bulkiness.

As shown, in the double-layer melt blown fibrous web according to an embodiment of the present invention, the covering weight 30 of the total weight of the multi-layer melt blown fibrous web without the covering fabric (30) The weight percentage of staple fiber is preferably 5 to 90% by weight in terms of vehicle manufacturer design requirements, sound absorbing and insulating properties, and bulkiness.

As shown in Figure 2 to 10, the method for producing a double-layer melt blown fiber web according to an embodiment of the present invention, (S1) step of introducing a thermoplastic resin composition to the extruder; (S2) extruding a thermoplastic resin composition; (S3) spinning the extruded thermoplastic resin composition in a filament form together with a high temperature and high pressure gas; (S4) A part of the radiated filaments is laminated in one direction with a certain pattern on the collector as they are to form a transverse fibrous layer 10, and the other part has a certain pattern on the transverse fibrous layer 10 Forming a longitudinal fiber layer (20) in a laminated direction; (S5) winding the produced melt blown fiber web; As shown in FIG.

As used herein, the term thermoplastic resin means a resin capable of repeatedly performing a work of melting and melting a polymer resin with a heat higher than the melting point, and solidifying the same. The degree of crystallinity of the polymer can be divided into crystalline and amorphous according to the size. Crystalline thermoplastics include polyethylene, polypropylene, nylon and the like, and amorphous thermoplastics include polyvinyl chloride and polystyrene.

As used herein, the term polyolefin refers to any of the polymeric hydrocarbon series of saturated open chains consisting solely of carbon and hydrogen atoms. Typical polyolefins include polyethylene, polypropylene, polymethylpentene and various combinations of ethylene, propylene and methylpentene monomers.

As used herein, the term polypropylene includes not only a homopolymer of propylene, but also a copolymer which is a propylene unit having a repeating unit of 40% or more.

As used herein, the term polyester is a concept which is linked by the formation of ester units and which contains at least 85% of the repeating units are condensation products of dicarboxylic acid with dihydroxy alcohols. These include aromatic, aliphatic, saturated and unsaturated diacids and these alcohols. As used herein, the term polyester includes copolymers and blends and variants thereof. A common example of polyester is polyethylene terephthalate (PET), a condensation product of ethylene glycol and terephthalic acid.

As used herein, the term meltblown microfibers or meltblown filaments refers to fibers or filaments formed by extruding a molten, processable polymer through a plurality of fine capillaries with a high-temperature, high-pressure compressed gas. Here, the capillary may be variously changed, such as a polygon including a circle, a triangle and a square, an asterisk, and the like. Further, as an example, a high-temperature, high-pressure compressed gas can reduce the diameter of the filament of the molten thermoplastic polymer material to about 0.3 to 10 mu m. The meltblown fibers may be discontinuous fibers or continuous fibers. 70 to 80 or 90% of the meltblown microfine fibers may have a diameter of 10 탆 or less. Ten, twenty, or thirty percent of the meltblown microfine fibers may have a diameter of 3 탆 or less.

The term " spunbond fiber " as used herein means a fiber web produced by a method of drawing a plurality of fine diameter filaments extruded through a capillary tube by using a hot tube. The spunbond fibers are continuous in the length direction of the filaments and the average diameter of the filaments is greater than about 5 占 퐉.

Hereinafter, a method for manufacturing a meltblown fiber web and an apparatus for manufacturing the same according to a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings. FIG. 1 is a schematic view of a meltblown fiber web according to Example 1 of the present invention, FIG. 2 is an explanatory view of a meltblown fiber web manufacturing process according to Example 1 of the present invention, FIG. 3 is a detailed view of a meltblown fiber web manufacturing process according to Example 1 of the present invention, FIG. 4 is an explanatory view of a meltblown fiber web manufacturing process according to Example 2 (including a staple pie bar) Fig. 5 is an explanatory view of a process of manufacturing a meltblown fiber web according to Example 3 (addition of foam part) of the present invention, Fig. 6 is a view showing a meltblown fiber web according to an embodiment of the present invention 7 is a block diagram of a comparative example 1 fiber web (only a transverse layer exists, no staple fiber), and a comparative example 2 fiber web (a transverse layer and a staple fiber).

≪ Example 1 >

Meltblown fiber webs were prepared according to the process of the manufacturing process of the meltblown fiber webs of FIGS. 2 and 3, which are the manufacturing method of the present invention. Specific manufacturing conditions are as follows.

99.8 wt% homopolypropylene H7914 polymer resin of LG Chem Co., Ltd., having a melt index of 230 (占 폚, g / 10min) of 1400 and an ultraviolet stabilizer Tinuvin 622 (manufactured by Ciba special chemical) Tinuvin 622) and a heat-resistant stabilizer, Irganox 1010 (0.1 wt%).

The thermoplastic resin composition (1) was kneaded, heated and extruded by rotating a single extruder having a Length / Dimension of 1/28 per minute at 80 revolutions per minute. Thereafter, the fiber was radiated toward the collector through an orifice (3A) inside the spinning die (3) having a diameter of orifice of 0.2 mm and a number of 32 per inch and a diameter of 2 m. At this time, the fibers were collided with the high-temperature and high-velocity gas ejected from the high-temperature and high-velocity gas ejection openings 4AA and 4BB provided symmetrically inside the spinning die 3 to produce the meltblown microfibers.

A meltblown fiber having a weight of 200 g / m 2 was prepared with the vertical distance between the spinning die 3 and the collecting device 7 being 70 cm and the speed of the collecting lance 7 being 2.5 m / min. 50wt% of the melt-blown microfibers 5 emitted from the spinneret 3 reached the collector 7 immediately without going through the laminate morphing device 6 of the present invention and were laminated in the horizontal direction, ) Of 50% by weight of the melt-blown microfibers 5 radiated from the melt-blown microfibers 5 is vertically changed in the direction of the microfibers 5 through the laminate- .

A meltblown microfine fiber web having a total weight of 230 g / m < 2 > was prepared by laminating the 200 g / m < 2 > meltblown fiber web prepared above with a spunbond nonwoven fabric having 15 g / m &

The working conditions of the laminate type changing apparatus of this embodiment are as follows. The laminate type changing device of the present invention used in this embodiment is a roll type steel sheet roll A 'having a length of 2,200 mm and a diameter of 100 pi and made of steel and having the same size as that of the steel roll A, And a mesh belt C made of a material is connected. The distance E between the steel roll A and the steel roll A is 400 mm and the steel roll A and the steel roll A 'are rotated at the same speed in the same direction as in Figs. 3 (a and 3) And a suction device B for sucking the high-temperature, high-pressure gas ejected from the spinneret is provided in the stainless steel mesh belt C of the laminate shape changing device 6. [ The vertical distance D between the laminate type changing device 6 and the radiation die 3 is 35 cm and the vertical distance D 'between the laminate type changing device 6 and the collecting device 7 is set to 25 cm. The position of the laminate morphing device 6 was also positioned such that the meltblown microfibers 5 emitted from the spinning die 3 could collect 50 wt%.

1 is a cross-sectional view of a meltblown fiber web prepared by Example 1. Fig. The thickness, weight, compressive modulus and sound absorption of the meltblown fiber web prepared in the above examples were measured. The thickness of the fiber web was measured according to 5.3 of the technical standard ISO 9073-2, which is a nonwoven fabric thickness measuring method, and five specimens of 100 mm × 100 mm in weight were taken from the specimens and the weights were measured. Respectively.

The compressive restoring force of the fiber web was measured according to Section 4.8 of MS341-17. The sound absorption performance was tested according to the reverberation method of Technical Standard GM 14177. The mite avoidance evaluation test was conducted according to the passing test method of the technical standard FC-TM-21. The thickness (10HD) and weight of the meltblown fibrous web 10AH laminated in the horizontal direction in Fig. 1 are 5 mm and 100 g / m 2, respectively. In addition, the vertically laminated meltblown fiber web (10AV) has a thickness (10VD) and a weight of 8mm and 100g / m 2, respectively.

≪ Example 2: Including staple pie bar >

A meltblown fibrous web was prepared by the apparatus and process of FIG. 99.8 wt% homopolypropylene H7914 polymer resin of LG Chem Co., Ltd., having a melt index of 230 (占 폚, g / 10min) of 1400 and an ultraviolet stabilizer Tinuvin 622 (manufactured by Ciba special chemical) Tinuvin 622) and a thermostable stabilizer, Irganox 1010 (0.1 weight%) were added to the thermoplastic resin composition (1).

The thermoplastic resin composition (1) was kneaded, heated and extruded by rotating a single extruder having a Length / Dimension of 1/28 per minute at 80 revolutions per minute. Thereafter, the fiber was radiated toward the collector through an orifice (3A) inside the spinning die (3) having a diameter of orifice of 0.2 mm and a number of 32 per inch and a diameter of 2 m. At this time, the fibers were collided with the high-temperature and high-velocity gas ejected from the high-temperature and high-velocity gas ejection openings 4AA and 4BB provided symmetrically inside the spinning die 3 to produce the meltblown microfibers.

A staple fiber feeding device was installed at a position 10 cm from the spinning die 3 toward the collector 7 to form a staple fiber of polypropylene material having a diameter of 40 mu m and an average length of 39 mm in a proportion of 20 wt% (5). A meltblown fibrous web having a weight of 200 g / m < 2 > was prepared with the vertical distance between the spinning die 3 and the collecting device 7 being 70 cm and the speed of the collecting lance 7 being 2 m / min. 50 wt% of the melt-blown microfibers 5 emitted from the spinneret 3 reached the collector 7 immediately without going through the laminate morphing device 6 of the present invention and were laminated in the horizontal direction, ) Of 50% by weight of the melt-blown microfibers 5 radiated from the melt-blown microfibers 5 are vertically changed in the direction of the microfibers 5 through the laminate- .

Collector in spinning die 3 A meltblown microfibrous web of 200 g / m < 2 > prepared above was laminated with a spunbond nonwoven fabric having 15 g / m < 2 > on both sides to prepare a meltblown microfiber fiber web having a total weight of 230 g / m &

≪ Comparative Example 1 &

Compared with the above-described first embodiment, all of the meltblown microfibers 5 emitted from the spinning die 3 without using the laminate shape changing device 6 of the present invention are stacked in the horizontal direction in the collector, A meltblown microfine fiber web having a total weight of 230 g / m < 2 > was prepared by laminating a meltblown fiber web with a spunbonded nonwoven fabric (cover bubble) having 15 g / m < 2 >

< Comparative Example 2>

Compared with the above-described second embodiment, the meltblown microfibers 5 emitted from the spinning die 3 are all stacked in the horizontal direction in the collector without using the laminate shape changing device 6 of the present invention, A meltblown microfine fiber web having a total weight of 230 g / m &lt; 2 &gt; was prepared by laminating a meltblown fiber web with a spunbonded nonwoven fabric (cover bubble) having 15 g / m &lt; 2 &gt;

<Comparison Review>

FIG. 8 shows the results of tests of Example 1, Example 2, Comparative Examples 1 and 2, FIG. 9 shows results of the sound absorption properties of Example 1 and Comparative Example 1, and FIG. 10 shows the results of sound absorption characteristics tests of Example 2 and Comparative Example 2. Table 1 in Fig. 8 is a measurement of the thickness and weight of the meltblown fiber web produced according to the conditions of Examples 1 and 2 and Comparative Examples 1 and 2. Table 2 in Fig. 8 shows the compression modulus measurement results and mite penetration test results of the heat-resistant and humidity-resistant conditions of Examples 1 and 2 and Comparative Examples 1 and 2.

Comparing the results of Examples 1 and 2 and Comparative Examples 1 and 2 of Tables 1 and 2 in FIG. 8, the effect of the present invention can be clearly confirmed. When the meltblown fibrous webs in the vertical direction are laminated on the meltblown fibrous webs laminated in the horizontal direction using the laminate modifying apparatus of the present invention, Is improved by 30 to 41%. Comparing the compressive modulus results of Example 1 and Comparative Example 1, it was found that the meltblown fiber web constituted by the combination of the vertical direction and the horizontal direction was 46% in the case of the heat-resistant condition as compared with the meltblown fiber web constituted only in the horizontal direction, It can be confirmed that the condition is improved by 10%.

8, the compressive modulus results of Example 2 and Comparative Example 2 are compared with each other. As compared with the meltblown fiber web in which the meltblown fiber web is composed only in the vertical direction in the combination of the vertical direction and the horizontal direction, 20% and 10%, respectively. Here, it can be seen that the difference in compressive modulus in the heat-resistant conditions of Examples 1 to 2 is significantly larger than the difference in compressive modulus in the heat-resistant conditions of Examples 2 to 2. This is because when the polypropylene staple fiber is mixed , And the heat-resistant compressive modulus characteristic is better than that of the case where it is not.

In FIG. 8, it is noted that Examples 1 and 2 did not pass ticks in the tick test, but failed tick tests in Comparative Examples 1 to 2. This is because the inner structure of the meltblown fiber web of the lamination combination in the horizontal direction and the lamination in the vertical direction of the present invention is more compact than that of Comparative Examples 1 to 2 having only the lamination structure in the horizontal direction Results.

Table 3 of FIG. 9 shows the results of measuring the blemish performance of Example 1 and Comparative Example 1, and Table 4 of FIG. 10 shows the results of measuring the blemish performance of Example 2 and Comparative Example 2. As a result of the above experiment, Example 1 showed better sound absorption performance than Comparative Example 1, and Example 2 has improved sound absorption performance as compared with Comparative Example 2. This is because the inner structure of the meltblown fibrous web of the lamination combination in the horizontal direction and the lamination in the vertical direction of the present invention is more dense and has a smaller internal structure than that of Comparative Example 1 to Comparative Example 2 having only the lamination structure in the horizontal direction This is the result of bulky. That is, the meltblown fiber web of the present invention and its manufacturing method are more bulky than those of the conventional production methods, have excellent compressive modulus, A dense meltblown fibrous web can be produced.

As shown in FIGS. 8 to 10, it can be seen that the sound absorbing characteristic of the product of the present invention is improved in the important frequency range of the automobile noise control.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, but on the contrary, &Lt; RTI ID = 0.0 &gt; and / or &lt; / RTI &gt;

It is to be understood that the appended claims are intended to supplement the understanding of the invention and should not be construed as limiting the scope of the appended claims.

10:
20:
30: Covers for cover

Claims (10)

A horizontal fiber layer (10) in which one side portion (F1) of meltblown superfine fibers (F) are laminated on each other in a transverse direction,
A vertical fiber layer 20 formed by extending the other side F2 of the meltblown microfine fibers F upward from the upper end of the one side portion F1 of the meltblown microfine fibers F, Layer,
And the end portion F3 of the other side F2 of the meltblown microfine fibers F forms a curl portion F3 of a shape of a downwardly curved shape. Raw fiber web. The method of claim 1,
Characterized in that the other side (F2) of the meltblown microfine fibers (F2) extends upwardly curl. The method of claim 1,
A first branch line 11a and a second branch line 11b are formed on the lower side of the transverse fiber layer 10 at a lower portion of the branch line 11 in the direction in which the fibers are laid and a first array line F2 of one side F2 of the meltblown ultra- 10b, the average arrangement angle (A)
With no external load and freely unfolded or with covering fabric (30, Covering Fabric) and without external load, freely unfolded,
Melt blown fibrous web having a double structure, characterized in that 0.001 ~ 45 degrees. The method of claim 1,
A second branch line 11a of the branch line 11a and a second branch line 11b of the other side branch F2 of the meltblown microfine fibers F are arranged on the lower side of the transverse fiber layer 10, (B) of the longitudinal fiber layers constituted by the longitudinally-
With no external compressive load and freely unfolded or covered with covering fabric (30) and without external compressive load and pulled upwards by 0.1 to 2 times the total thickness of the freely unrolled or unloaded fiber web,
Melt blown fibrous web having a dual structure, characterized in that 45 ~ 90 degrees. The method of claim 1,
The crossing angle (C) of the horizontal fiber layer average arrangement angle (A) and the vertical fiber layer average arrangement angle (B) is
Up to 0.1 to 2 times the total thickness of the fiber web in the freely unrolled or covering fabric (30) and free from unrolled or unrolled or by external forces With pulled,
Melt blown fibrous web having a dual structure, characterized in that 1 ~ 89 °. The method of claim 1,
Further comprising a staple fiber for interweaving the meltblown superfine fibers together. &Lt; RTI ID = 0.0 &gt; 21. &lt; / RTI &gt; The method of claim 1,
Covering fabric 30 surrounding the melt-blown fibrous web further comprises a covering fabric (30, Covering Fabric) is a melt blown having a dual structure characterized in that the non-woven fabric made of spunbond fibers New fiber web. The method of claim 1,
The thickness ratio of the transverse fiber layer 10 to the longitudinal fiber layer 10 is,
Up to 0.1 to 2 times the total thickness of the fiber web in the freely unrolled or covering fabric (30) and free from unrolled or unrolled or by external forces With pulled,
Melt blown fibrous web having a dual structure, characterized in that 1: 1 to 1: 9. The method according to claim 6,
Melt blown fiber having a double structure, characterized in that the weight percentage of the total weight of the melt blown fiber web without covering cloth (30, Covering Fabric) is 5 to 90% by weight Web. (S1) injecting a thermoplastic resin composition into an extruder;
(S2) extruding a thermoplastic resin composition;
(S3) spinning the extruded thermoplastic resin composition in a filament form together with a high temperature and high pressure gas;
(S4) A part of the radiated filaments is laminated in one direction with a certain pattern on the collector as they are to form a transverse fibrous layer 10, and the other part has a certain pattern on the transverse fibrous layer 10 Forming a longitudinal fiber layer (20) in a laminated direction;
(S5) winding the produced melt blown fiber web; Wherein the meltblown fibrous web has a double structure.

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