CN109943980B

CN109943980B - Non-woven fabric structure and manufacturing method thereof

Info

Publication number: CN109943980B
Application number: CN201711379778.8A
Authority: CN
Inventors: 林英骐; 廖元培; 彭兆群
Original assignee: Taiwan Textile Research Institute
Current assignee: Taiwan Textile Research Institute
Priority date: 2017-12-20
Filing date: 2017-12-20
Publication date: 2021-02-23
Anticipated expiration: 2037-12-20
Also published as: CN109943980A

Abstract

A non-woven fabric structure and a manufacturing method thereof. The manufacturing method of the non-woven fabric structure comprises the following steps: providing a screen of meltblown fibers comprised of a plurality of meltblown fibers; a plurality of filaments are fed into a curtain of meltblown fibers to entangle the filaments with each other, and the entangled composite of the filaments and the curtain of meltblown fibers is collected and solidified to obtain a nonwoven fabric structure. The filaments and the melt-blown fibers are uniformly entangled to improve the transverse tensile strength of the non-woven fabric structure, so that the transverse tensile strength of the non-woven fabric structure approaches to the longitudinal tensile strength.

Description

Non-woven fabric structure and manufacturing method thereof

Technical Field

The invention relates to a non-woven fabric structure and a manufacturing method thereof.

Background

With the development of textile industry, various fabrics have been widely used in our daily lives. According to the difference of the manufacturing methods, the cloth can be roughly divided into woven cloth that needs to be woven and non-woven cloth that does not need to be woven. In recent years, the field of application of nonwoven fabrics has been extended to the technical fields of filter materials, medical dressings, and the like, in addition to the apparel industry.

However, although the nonwoven fabric has advantages of easy and low cost, it has a problem of insufficient tensile strength, so that it is often necessary to sew, bond the nonwoven fabric to another substrate, or bond the nonwoven fabric to a glue to increase the tensile strength of the finished nonwoven fabric. However, the above processing method requires additional process steps, and the nonwoven fabric product becomes thick, heavy and tight, which affects the bulkiness of the product.

Disclosure of Invention

In view of the above, an embodiment of the present invention provides a nonwoven fabric structure and a method for manufacturing the same, so as to improve the tensile strength of the nonwoven fabric structure.

One aspect of the present invention is a method for making a nonwoven fabric structure, comprising the following steps. A filament curtain of meltblown fibers is provided that is formed from a plurality of meltblown fibers. A plurality of filaments are fed into a curtain of meltblown fibers to entangle the filaments with each other, and the entangled composite of the filaments and the curtain of meltblown fibers is collected and solidified to obtain a nonwoven fabric structure.

In some embodiments, the method of making a nonwoven fabric structure further comprises feeding the filaments 5 to 7 centimeters after the plurality of meltblown fibers exit the spinneret.

In some embodiments, the filaments are fed at an angle of 45 to 90 degrees relative to the direction of the multiple meltblown fibers.

In some embodiments, the filaments may be filament bundles formed by air-flow splitting.

In some embodiments, the curtain of meltblown fibers may be the same material as the filaments.

The present invention is also directed to a nonwoven fabric structure comprising a meltblown web and a plurality of filaments entangled in the meltblown web, wherein the average basis weight ratio of any two points of the nonwoven fabric structure is 0.95-1.05.

In some embodiments, the ratio of the tensile strength of the nonwoven fabric structure in the transverse direction to the tensile strength in the longitudinal direction is 0.92-0.99.

In some embodiments, the filaments are continuous rayon fibers without twisting, and the material is a polyolefin, polyester, polyurethane, or aramid.

In some embodiments, the filament can have a fiber size of 250 to 350d/48 f.

In some embodiments, the weight percentage of the filaments in the nonwoven structure may be between 26% and 50%.

The non-woven fabric structure and the manufacturing method thereof can improve the transverse tensile strength of the non-woven fabric structure by uniformly intertwining the filaments and the melt-blown fibers, so that the transverse tensile strength of the non-woven fabric structure approaches to the longitudinal tensile strength.

Drawings

In order to make the aforementioned and other objects, features, and advantages of the invention, as well as others which will become apparent, reference should be made to the following detailed description of the preferred embodiments, taken in conjunction with the accompanying drawings, in which:

FIGS. 1 and 2 are a flow chart and a schematic diagram of one embodiment of a method of making a nonwoven structure of the present invention;

FIG. 3 is a schematic view of one embodiment of a nonwoven structure of the present invention;

FIGS. 4A-4C are schematic cross-sectional views of different embodiments of nonwoven structures of the present invention;

FIG. 5 is a schematic view of another embodiment of a method of making a nonwoven structure of the present invention;

FIG. 6 is a schematic view of another embodiment of the method for making a nonwoven fabric of the present invention.

Detailed Description

While the spirit of the invention will be described in detail and with reference to the drawings, those skilled in the art will understand that various changes and modifications can be made without departing from the spirit and scope of the invention as taught herein.

Please refer to fig. 1 and fig. 2, which are a flowchart and a schematic diagram of a method for manufacturing a nonwoven fabric structure according to an embodiment of the present invention. The nonwoven structure is made by the method beginning at step S10, step S10 providing a screen 210 of meltblown fibers, the screen 210 being formed from a plurality of meltblown fibers 212. The curtain of meltblown fibers 210 may be provided by a meltblowing mechanism 110.

In one embodiment, the meltblowing mechanism 110 may include a nozzle 112 and a dope supply unit 114 coupled to the nozzle 112. The spinning material supply unit 114 is used for supplying the melted polymer spinning material to the nozzle 112. The nozzle 112 may be connected to a high voltage power source so that the polymer solution dope supplied from the dope supply unit 114 is charged after passing through the nozzle 112. Since the polymer materials with the same electrical property repel each other and are dispersed to form the melt-blown fiber 212 with very fine fiber diameter.

Next, in step S20, a plurality of filaments 222 are fed into the curtain of meltblown fibers 210 to entangle with each other. The direction of feed of the filaments 222 is not parallel to the direction of discharge of the curtain of meltblown fibers 210 so that the filaments 222 are spatially entangled with the meltblown fibers 212 in an irregular, three-dimensional cross-entanglement. Because the filaments 222 are continuous fibers and the filaments 222 have a diameter greater than the diameter of the meltblown fibers 212, feeding the filaments 222 into the curtain 210 of meltblown fibers entangles the filaments to increase the strength of the finished nonwoven structure 200.

In one embodiment, filaments 222 are formed from tow 220 by air-splitting. For example, bundles of filaments 220 are dispersed into a plurality of filaments 222 after passing through the air-stream fiber-separating mechanism 120, and are further jetted into the curtain 210 of meltblown fibers by the air stream, and the filaments 222 are entangled with the uncured meltblown fibers 212 after contacting them.

Finally, step S30 is to collect and solidify the entangled composite of filaments 222 and meltblown fiber veil 210 to obtain nonwoven structure 200. In one embodiment, the collecting mechanism 130 is disposed below the meltblowing mechanism 110 to collect the entangled composite of the filaments 222 and the curtain of meltblown fibers 210.

In one embodiment, the collecting mechanism 130 includes a conveyor 132, a suction device 134, and a plurality of rollers 136. The entangled composite of filaments 222 and curtain of meltblown fibers 210 falls onto conveyor 132, and air extractor 134 is positioned below conveyor 132, and air extractor 134 is used to shape the entangled composite of filaments 222 and curtain of meltblown fibers 210. The rollers 136 are arranged in pairs on both upper and lower sides of the conveyor belt 132 to contact the entangled composite of the filaments 222 and the curtain of meltblown fibers 210, such that the entangled composite of the filaments 222 and the curtain of meltblown fibers 210 becomes the nonwoven structure 200 having a uniform thickness after passing through the rollers 136.

Referring to fig. 2 and fig. 3, fig. 3 is a schematic view of a nonwoven structure 200 according to an embodiment of the present invention. The nonwoven structure 200 includes a meltblown web 214 formed from the meltblown fibers described above, and filaments 222 entangled in the meltblown web 214. The basis weight of the nonwoven structure 200 may be adjusted by varying the ratio between the meltblown web 214 and the filaments 222, such as by varying the rate of ejection from the meltblowing mechanism 110 and/or the rate of feed of the filaments 222. Alternatively, the weight of the non-woven fabric structure 200 may be changed by adjusting the conveying speed of the conveying belt 132.

As described above, since the continuous filaments 222 are fed to the meltblown fiber filament curtain 210 to be entangled in a random direction while the nonwoven fabric structure 200 is manufactured, and since the plurality of filaments 222 are obtained by air-stream separation of the filament bundle 220, the plurality of filaments 222 are continuously and dispersedly fed to the meltblown fiber filament curtain 210 in a large width, the nonwoven fabric structure 200 can have good uniformity and tensile strength.

In one embodiment, the weight of the nonwoven structure 200 may be measured after being cut and sampled to obtain an average weight of each point. For example, after the non-woven fabric structure 200 is cut into nine blocks, such as a-I, the fabric weights of the blocks are measured to obtain the average fabric weight of each point in the blocks. In this embodiment, the average weights of any two points in the nonwoven structure 200, i.e. any two points in the blocks a to I, are calculated respectively, and the ratio of the two average weights is 0.95-1.05, which means that the filaments 222 of this embodiment are uniformly distributed in the nonwoven structure 200.

In one embodiment, the ratio of the tensile strength of the nonwoven fabric structure 200 in the transverse direction to the tensile strength in the longitudinal direction is 0.92-0.99. The aforementioned longitudinal tensile strength refers to the tensile strength of the nonwoven structure 200 in the long axis direction thereof, i.e., the machine direction (machine direction) parallel to the conveyor belt 132. The aforementioned transverse tensile strength refers to the tensile strength of the nonwoven structure 200 in its short axis direction, i.e., the cross direction (cross direction) perpendicular to the machine direction.

In general, conventional nonwoven fabrics are made of a mixture of staple fibers and meltblown fibers, so that the tensile strength in the machine direction is significantly better than that in the transverse direction. Compared to the conventional nonwoven fabric, the filaments 222 of the nonwoven fabric structure 200 disclosed in this embodiment are entangled with the meltblown fiber web 214 continuously and dispersedly in a large width, so that the tensile strength in the transverse direction is also good, and the tensile strength in the transverse direction of the nonwoven fabric structure 200 is close to the tensile strength in the longitudinal direction.

Filament 222 in this disclosure refers to an untwisted continuous rayon fiber. The material of the filaments 222 may be, but is not limited to, polyolefins (e.g., PP), polyesters (e.g., PET), polyurethanes (e.g., TPU), or aromatic polyamides (e.g., Techonra yarn). The filament 222 has a fiber size of 250 to 350d/48f, for example.

Meltblown fibers 212 are referred to herein as continuous direct spun fibers obtained from a meltblowing process. The material of the meltblown fibers 212 may be the same as the material of the filaments 222, such as a polyolefin (e.g., PP), a polyester (e.g., PET), a polyurethane (e.g., TPU), or an aromatic polyamide (e.g., Techonra yarn). The diameter of the melt-blown fiber 212 is, for example, 3 to 10 μm.

In one embodiment, the filaments 222 comprise 26% to 50% by weight of the nonwoven structure 200. If the weight percentage of the filaments 222 in the nonwoven structure 200 is less than 25%, there is no significant effect on improving the tensile strength in the cross direction of the nonwoven structure 200. If the weight percentage of the filaments 222 in the nonwoven structure 200 is greater than 50%, a problem may arise in that the filaments 222 are broken due to the high feed rate of the filaments 222.

Next, please refer to fig. 2 and fig. 4A to 4C, wherein fig. 4A to 4C are schematic cross-sectional views of different embodiments of the nonwoven fabric structure of the present invention. To provide good uniformity in the nonwoven structure, the filaments 222 are fed about 5 to 7 cm after the meltblown fibers 212 exit the nozzle 112, where the meltblown fibers 212 have left the nozzle 112 a distance and begin to solidify but have not yet completely solidified. As such, when the filaments 222 are entangled with the meltblown fibers 212, the filaments 222 are more uniformly mixed with the meltblown fibers 212, as shown in FIG. 4A.

If the filaments 222 are prematurely entangled with the meltblown fibers 212, if the filaments 222 are fed at a location about 3-5 cm after the meltblown fibers 212 exit the nozzle 112, the meltblown fibers 212 do not yet solidify and the filaments 222 tend to penetrate the curtain 210 of meltblown fibers and fail to intermingle sufficiently with them, such that the filaments 222 are deposited and protrude above the top surface of the resulting nonwoven structure 200.

In contrast, if the filaments 222 are too late entangled with the meltblown fibers 212, such as if the filaments 222 are fed about 7-10 cm after the meltblown fibers 212 exit the nozzle 112, and the meltblown fibers 212 are fully solidified, the filaments 222 are intercepted by the solidified curtain 210 of meltblown fibers and are likewise not sufficiently intermingled with the same, such that the filaments 222 are deposited on the lower surface of the resulting nonwoven structure 200.

Likewise, the filaments 222 are preferably oriented at an angle relative to the direction of the emission of the meltblown fibers 212: feeding the filaments 222 at 45-90 degrees. If the feed angle is too small (e.g., less than 30 degrees feed), the filaments 222 will not be sufficiently intermingled with the meltblown fiber veil 210.

Referring to fig. 5, a schematic diagram of another embodiment of the method for making a nonwoven fabric structure of the present invention is shown. The difference between this embodiment and the embodiment shown in fig. 2 is that the blowing device 140 is further disposed in this embodiment, and the blowing device 140 and the air flow fiber separating mechanism 120 are respectively located at opposite sides of the meltblown fiber curtain 210. The blower 140 may cooperate with the suction device 134 in the collection mechanism 130 to position the intermingled composite of filaments 222 and meltblown fibers 212 in a predetermined area on the conveyor belt 132.

Referring to fig. 6, it is a schematic view of another application example of the method for manufacturing the nonwoven fabric of the present invention. The method for manufacturing the non-woven fabric can also be applied to manufacturing the three-dimensional fabric. In the embodiment, the solid die 330 is fixed on the moving carrier 320, and the solid die 330 is disposed between the melt blowing mechanism 310 and the filament source 340 and can move up and down or rotate relative to the melt blowing mechanism 310 and the filament source 340 through the moving carrier 320.

The three-dimensional die 330 may be, for example, a shoe-type die, and the meltblown fibers 312 provided by the meltblowing mechanism 310 and the filaments 342 provided by the filament source 340 are attached to the three-dimensional die 330 to form a three-dimensional fabric. The moving carrier 320 may include a motor, an oil cylinder, a screw, and other mechanisms, such that the three-dimensional die 330 can rotate relative to the melt-blowing mechanism 310 and the filament source 340, and the three-dimensional die 330 can move up and down relative to the melt-blowing mechanism 310 and the filament source 340, so that the melt-blown fibers 312 and the filaments 342 can be coated on the surface of the three-dimensional die 330.

In one embodiment, the filament source 340 may be a roll of filaments 342 or a bundle of filaments. If the filament source 340 comprises a bundle of filaments, the filament source 340 further comprises an air-stream splitting mechanism to air-split the bundle of filaments to provide discrete filaments 342. As previously mentioned, the addition of continuous filaments 342 having a larger fiber diameter to the dimensional fabric helps to increase the tensile strength of the dimensional fabric.

In summary, an embodiment of the present invention provides a nonwoven fabric structure and a method for manufacturing the same, in which filaments and meltblown fibers are uniformly entangled to increase the transverse tensile strength of the nonwoven fabric structure, so that the transverse tensile strength of the nonwoven fabric structure approaches to the longitudinal tensile strength.

Although the present invention has been described with reference to the above embodiments, it should be understood that various changes and modifications can be made therein by those skilled in the art without departing from the spirit and scope of the invention.

Claims

1. A method for manufacturing a non-woven fabric structure is characterized by comprising the following steps:

providing a screen of meltblown fibers comprised of a plurality of meltblown fibers;

feeding a plurality of filaments into said curtain of meltblown fibers to entangle them with each other, wherein said plurality of filaments are formed by filament bundles dispersed by air-stream distribution; and

collecting and curing the composite of the filaments entangled with the curtain of meltblown fibers to obtain the nonwoven fabric structure.

2. The method of claim 1 further including feeding said filaments 5 to 7 cm after said plurality of meltblown fibers exit said nozzle.

3. The method of claim 1, wherein the filaments are fed at an angle of 45 to 90 degrees with respect to the direction of the plurality of meltblown fibers.

4. The method of making a nonwoven structure of claim 1 wherein said curtain of meltblown fibers is the same material as said filaments.

5. A nonwoven fabric structure, comprising:

a meltblown web; and

and the filaments are entangled in the melt-blown fiber web, wherein the average cloth weight ratio of any two points of the non-woven fabric structure is 0.95-1.05, and the filaments account for 26-50% of the non-woven fabric structure by weight.

6. The nonwoven structure of claim 5 wherein the ratio of the tensile strength in the cross direction to the tensile strength in the machine direction of the nonwoven structure is 0.92 to 0.99.

7. A nonwoven structure according to claim 5 characterised in that the filaments are continuous staple fibres without twisting and the material is a polyalkylene, polyester, polyurethane or aromatic polyamide.

8. A nonwoven structure according to claim 5 characterised in that the filaments have a fibre gauge of 250 to 350d/48 f.