Non-woven fabric and method and apparatus of manufacturing the same

Abstract

A nonwoven fabric includes a plurality of discontinuous fibers, a plurality of natural keratin fibers, and a plurality of meltblown fibers. The discontinuous fibers, the natural keratin fibers, and the meltblown fibers form a continuous bonding web structure.

Claims

1. A method for manufacturing a nonwoven fabric, the method comprising: processing a plurality of discontinuous fibers by a carding machine; directing airflow to blow a plurality of natural keratin fibers into spaces between the discontinuous fibers; and directing the airflow with the discontinuous fibers and the natural keratin fibers to a curtain of semi-molten meltblown fibers, such that the semi-molten meltblown fibers bond the discontinuous fibers and the natural keratin fibers to form a continuous bonding web structure.

2. The method of claim 1, further comprising: collecting the continuous bonding web structure to form a fabric roll.

3. The method of claim 1, further comprising: carding the discontinuous fibers and the natural keratin fibers by an air carding machine before directing the airflow with the discontinuous fibers and the natural keratin fibers to the curtain of semi-molten meltblown fibers; and wherein directing the airflow with the discontinuous fibers and the natural keratin fibers to the curtain of semi-molten meltblown fibers comprises: directing the airflow with the carded discontinuous fibers and the carded natural keratin fibers to the curtain of semi-molten meltblown fibers.

4. The method of claim 1, comprising carding discontinuous fibers and natural keratin fibers before directing the airflow with discontinuous fibers and natural keratin fibers to the curtain of semi-molten meltblown fibers.

5. The method of claim 1, wherein directing the airflow with the discontinuous fibers and the natural keratin fibers to the curtain of semi-molten meltblown fibers comprises: directing the airflow with the carded discontinuous fibers and the carded natural keratin fibers to the curtain of semi-molten meltblown fibers.

6. The method of claim 1, comprising fabricating a nonwoven fabric with a framework made of a plurality of discontinuous fibers, wherein a diameter of the discontinuous fibers is in a range from 283 m to 3050 m, and a length of the discontinuous fibers is in a range from 17 mm to 61 mm, wherein a plurality of natural keratin fibers fed into spaces between the discontinuous fibers formed using an import channel for directing airflow with the discontinuous fibers and the natural keratin fibers to a curtain of semi-molten meltblown fibers; and a plurality of meltblown fibers, wherein the meltblown fibers have a diameter in a range from 0.5 m to 100 m, and the meltblown fibers bond the fiber mixture as a continuous bonding web structure, where the semi-molten meltblown fibers bond the discontinuous fibers and the natural keratin fibers.

7. The method of claim 1, wherein the nonwoven fabric has from about 2.5 wt % to about 95 wt % of the discontinuous fibers, from about 2.5 wt % to about 95 wt % of the natural keratin fibers, and from about 2.5 wt % to about 95 wt % of the meltblown fibers.

8. The method of claim 1, wherein the meltblown fibers are made of any thermoplastic resin which is capable of being meltblown.

9. The method of claim 1, wherein the meltblown fibers are made of polypropylene (PP), polyethylene (PE), thermoplastic polyurethane (TPU), styrene-butadiene-styrene (SBS), thermoplastic elastomers (TPE), thermoplastic rubber (TPR), polyethylene terephthalate (PET), poly trimethylene terephthalate (PTT), polybutylene terephthalate (PBT), polylactate (PLA), cellulose, polystyrene (PS), polyamide (PA), polytetrafluoroethylene (PTFE), thermomelt plastic, ethylene-methyl acrylate copolymer (EMA), ethylene vinyl acetate copolymer (EVA), or any combination thereof.

10. The method of claim 1, wherein the discontinuous fibers are made of polypropylene (PP), polyethylene (PE), polyethylene terephthalate (PET), polybutylene terephthalate (PBT), nylon, acrylic, elastic fibers, rubber, elastane, or any combination thereof.

11. An apparatus for manufacturing a nonwoven fabric, the apparatus comprising: a carding machine for processing a plurality of discontinuous fibers; an air source for providing airflow; a feeding channel for directing the airflow to the carding machine to card the discontinuous fibers and to blow a plurality of natural keratin fibers into spaces between the discontinuous fibers; a meltblowing machine for providing a curtain of semi-molten meltblown fibers; and an import channel for directing the airflow with the discontinuous fibers and the natural keratin fibers to the curtain of semi-molten meltblown fibers, such that the semi-molten meltblown fibers bond the discontinuous fibers and the natural keratin fibers to form a continuous bonding web structure.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 is a drawing of a nonwoven fabric according to one embodiment of the present invention.

(2) FIG. 2 is a drawing of an apparatus for manufacturing a nonwoven fabric according to one embodiment of the present invention.

DETAILED DESCRIPTION

(3) In the following detailed description, for purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of the disclosed embodiments. It will be apparent, however, that one or more embodiments may be practiced without these specific details. In other instances, well-known structures and devices are schematically depicted in order to simplify the drawings.

(4) FIG. 1 is a drawing of a nonwoven fabric 100 according to one embodiment of the present invention. As shown in FIG. 1, the nonwoven fabric 100 includes a plurality of discontinuous fibers 110, a plurality of natural keratin fibers 120, and a plurality of meltblown fibers 130. The discontinuous fibers 110, the natural keratin fibers 120, and the meltblown fibers 130 form a continuous bonding web structure.

(5) In FIG. 1, the discontinuous fibers 110 can be the framework of the nonwoven fabric 100 to provide the nonwoven fabric 100 with suitable fluffiness, softness-stiffness, and resilience. The natural keratin fibers 120 have small air pockets to provide the nonwoven fabric 100 with insulation and warmth. Furthermore, the natural keratin fibers 120 can increase the compressional resilience of the nonwoven fabric 100 as well. The meltblown fibers 130 can bond the discontinuous fibers 110 and the natural keratin fibers 120 to form a continuous bonding web structure. Furthermore, since the meltblown fibers 130 and spaces between the meltblown fibers 130 are small enough, the meltblown fibers can enhance the insulation and warmth of the nonwoven fabric 100 as well.

(6) Relative to long fibers or continuous fibers, the discontinuous fibers 110, also known as short fibers, have a general aspect ratio (defined as the ratio of fiber length to diameter) ranging from about 20 to about 60. The length of the discontinuous fibers 110 may range from about 17 mm to about 61 mm. The discontinuous fibers 110 may be made of polypropylene (PP), polyethylene (PE), polyethylene terephthalate (PET), recycled PET, insulation PET, polybutylene terephthalate (PBT), nylon, acrylic, elastic fibers, rubber, elastane, or any combination thereof which has fiber formability, suitable softness-stiffness, and resilience.

(7) The natural keratin fibers 120 are made of natural keratin. Specifically, the natural keratin fibers 120 can be, for example, down and/or feathers of birds, animal fur, or any combination thereof.

(8) The meltblown fibers 130 are fibers manufactured by melt blowing. The diameter of the meltblown fibers 130 may range from about 0.5 m to about 100 m. In the present embodiment, the meltblown fibers 130 can bond the discontinuous fibers 110 and the natural keratin fibers 120 to form a continuous bonding web structure.

(9) The meltblown fibers 130 are made of any thermoplastic resin which is capable of being meltblown, for example polypropylene (PP), polyethylene (PE), thermoplastic polyurethane (TPU), styrene-butadiene-styrene (SBS), thermoplastic elastomers (TPE), thermoplastic rubber (TPR), polyethylene terephthalate (PET), poly trimethylene terephthalate (PTT), polybutylene terephthalate (PBT), polylactate (PLA), cellulose, polystyrene (PS), polyamide (PA), polytetrafluoroethylene (PTFE), thermomelt plastic, ethylene-methyl acrylate copolymer (EMA), ethylene vinyl acetate copolymer (EVA), or any combination thereof.

(10) The weight ratio of the discontinuous fibers 110, the natural keratin fibers 120, and the meltblown fibers 130 in the nonwoven fabric 100 of FIG. 1 depends on actual requirements. In the present embodiment, the nonwoven fabric 100 has from about 2.5 wt % to about 95 wt % of the discontinuous fibers 110, from about 2.5 wt % to about 95 wt % of the natural keratin fibers 120, and from about 2.5 wt % to about 95 wt % of the meltblown fibers 130.

(11) The nonwoven fabric 100 of FIG. 1 has a base weight ranging from about 50 g/m.sup.2 to about 500 g/m.sup.2 and a thickness ranging from about 0.3 mm to about 50 mm. It should be appreciated that the aforementioned specifications of the nonwoven fabric 100 are illustrative only and should not limit the claimed scope of the present disclosure. Any one of ordinary skill in the art should be able to determine the specifications of the nonwoven fabric according to actual requirements.

(12) FIG. 2 is a drawing of an apparatus 200 for manufacturing a nonwoven fabric 100 according to one embodiment of the present invention. As shown in FIG. 2, the apparatus 200 for manufacturing the nonwoven fabric 100 includes a carding machine 210, an air source 220, a feeding channel 230, a meltblowing machine 240, and an import channel 250. The carding machine 210 is for processing a plurality of discontinuous fibers 110. The air source 220 is for providing airflow 225. The feeding channel 230 is for directing the airflow 225 to the carding machine 210 to card the discontinuous fibers 110 and to blow a plurality of natural keratin fibers 120 into the spaces between the discontinuous fibers 110. The meltblowing machine 240 is for providing a curtain of semi-molten meltblown fibers 245. The import channel 250 is for directing the airflow 225 with the discontinuous fibers 110 and the natural keratin fibers 120 to the curtain of semi-molten meltblown fibers 245, such that the semi-molten meltblown fibers 130 bond the discontinuous fibers 110 and the natural keratin fibers 120 to form a continuous bonding web structure.

(13) The carding machine 210 is a machine that can disentangle, clean and intermix the discontinuous fibers 110. In the present embodiment, the carding machine 210 includes a cylinder carding cloth. In use, the cylinder carding cloth which rotates at high speeds can catch the discontinuous fibers 110 and move the discontinuous fibers 110 to a place adjacent to the feeding channel 230 where the discontinuous fibers 110 and the natural keratin fibers 120 are mixed. The specifications of the cylinder carding cloth depend on the required mixing uniformity. In the present embodiment, the density of the cylinder carding cloth may range from about 3 p/in to about 120 p/in. The angle of the cylinder carding cloth may vary from about 27 to about 80. The angle of the cylinder carding cloth may affect the properties of the discontinuous fibers 110 which may be broken up by the cylinder carding cloth.

(14) The air source 220 may be a blower. The flowing rate of the airflow 225 may vary from about 1 m/s to about 60 m/s.

(15) As shown in FIG. 2, the feeding channel 230 is connected to a place below the cylinder carding cloth, i.e. the carding machine 210, such that the natural keratin fibers 120 are not caught and broken up by the cylinder carding cloth, i.e. the carding machine 210. In the case that some of the natural keratin fibers 120 need to be broken up in manufacturing the nonwoven fabric 100, the feeding channel 230 may be connected to a place above the cylinder carding cloth, i.e. the carding machine 210. By such an arrangement, the cylinder carding cloth, i.e. the carding machine 210, can catch the natural keratin fibers 120, and some of the natural keratin fibers 120 may be broken up by the cylinder carding cloth, i.e. the carding machine 210. Any one of ordinary skill in the art should be able to determine the detail structure of the feeding channel 230 according to actual requirements.

(16) The feeding rate of the discontinuous fibers 110 depend on the required weight ratio. In the present embodiment, the feeding rate of the discontinuous fibers 110 may range from about 1 m/min to about 3 m/min. The number and distribution of the natural keratin fibers 120 depend on the gaps of the cylinder carding cloth, i.e. the carding machine 210, and the rate of the airflow 225.

(17) Whether the discontinuous fibers 110 and the natural keratin fibers 120 are broken up by the cylinder carding cloth, i.e. the carding machine 210, almost all of the discontinuous fibers 110 and the natural keratin fibers 120 can be blown into the curtain of semi-molten meltblown fibers 245. Even if a very small part of the discontinuous fibers 110 and the natural keratin fibers 120 is caught on the cylinder carding cloth, i.e. the carding machine 210, this part of the discontinuous fibers 110 and the natural keratin fibers 120 will be used in the next turn of the cylinder, and thus the number of void if any will be minimized to undetectable.

(18) The semi-molten meltblown fibers 130 bond the discontinuous fibers 110 and the natural keratin fibers 120 at a place ranging from about 1 cm to about 50 cm below the die of the meltblowing machine 240 after the discontinuous fibers 110 and the natural keratin fibers 120 are blown into the curtain of semi-molten meltblown fibers 245. Since the meltblown fibers 130 are semi-molten at this time, the semi-molten meltblown fibers 130 can stick to the discontinuous fibers 110 and the natural keratin fibers 120 and also encompass them together before solidifying. In this way, the discontinuous fibers 110, the natural keratin fibers 120, and the meltblown fibers 130 are firmly bonded together to form a continuous bonding web structure with good abrasion and pilling resistance. The process air pressure of the meltblowing machine 240 may range from about 5 psi to about 15 psi.

(19) As shown in FIG. 2, the apparatus 200 for manufacturing the nonwoven fabric 100 may further include a collecting device 260. The collecting device 260 is for collecting the continuous bonding web structure formed by the discontinuous fibers 110, the natural keratin fibers 120, and the meltblown fibers 130 to form a fabric roll. In the present embodiment, the collecting device 260 may be a conveyor belt, a roller, a vacuum pump, or any combination thereof. Furthermore, the vertical distance between the die of the meltblowing machine 240 and the collecting device 260 may range from about 10 cm to about 50 cm.

(20) Another aspect of the present invention is a method for manufacturing a nonwoven fabric 100. The method for manufacturing the nonwoven fabric 100 includes the following steps: (The steps are not recited in the sequence in which the steps are performed. That is, unless the sequence of the steps is expressly indicated, the sequence of the steps is interchangeable, and all or part of the steps may be simultaneously, partially simultaneously, or sequentially performed.)

(21) (1) processing a plurality of discontinuous fibers 110 by a carding machine 210;

(22) (2) directing airflow 225 to blow a plurality of natural keratin fibers 120 into the spaces between the discontinuous fibers 110; and

(23) (3) directing the airflow 225 with the discontinuous fibers 110 and the natural keratin fibers 120 to a curtain of semi-molten meltblown fibers 245, such that the semi-molten meltblown fibers 130 bond the discontinuous fibers 110 and the natural keratin fibers 120 to form a continuous bonding web structure.

(24) In one or more embodiments of the present invention, the method for manufacturing the nonwoven fabric 100 may further include the following steps:

(25) (4) collecting the continuous bonding web structure formed by the discontinuous fibers 110, the natural keratin fibers 120, and the meltblown fibers 130 to form a continuous fabric roll with some physical strength.

(26) In one or more embodiments of the present invention, the method for manufacturing the nonwoven fabric 100 may further include the following steps:

(27) (2.5) carding the discontinuous fibers 110 and the natural keratin fibers 120 by an air carding machine before directing the airflow 225 with the discontinuous fibers 110 and the natural keratin fibers 120 to the curtain of semi-molten meltblown fibers 245.

(28) That is, the discontinuous fibers 110 and the natural keratin fibers 120 are carded by the air carding machine before blown into the curtain of semi-molten meltblown fibers 245. In this way, the discontinuous fibers 110 and the natural keratin fibers 120 can be mixed more uniformly, and therefore the quality of the nonwoven fabric 100 is improved.

(29) The air carding machine is a sub-element of the carding machine 210 which can card and mix the discontinuous fibers 110 and the natural keratin fibers 120 uniformly.

(30) In one or more embodiments of the present invention, the step (3) may includes:

(31) (3.1) directing the airflow 225 with the carded discontinuous fibers 110 and the carded natural keratin fibers 120 to the curtain of semi-molten meltblown fibers 245, such that the semi-molten meltblown fibers 130 bond the discontinuous fibers 110 and the natural keratin fibers 120 to form a continuous bonding web structure.

Working Example

(32) A series of tests were run to determine that the aforementioned apparatus and method could manufacture the required nonwoven fabrics. The parameters described before are not repeated hereinafter, and only further information is supplied to actually perform the series of tests.

(33) In the following working examples 1-3, the nonwoven fabrics were manufactured by the apparatus of FIG. 2. The specifications and manufacturing parameters are listed in the following table 1. In the following working examples 1-3, the discontinuous fibers were made of polyethylene terephthalate (PET), the natural keratin fibers were 650 fill power down, and the meltblown fibers were made of polypropylene (PP).

(34) TABLE-US-00001 TABLE 1 Specifications and Manufacturing Parameters of Working Example 1-3 Working Working Working Example 1 Example 2 Example 3 Feeding Rate of Natural 12.3 11.6 6.8 Keratin Fibers (Hz) Distribution Airflow of 60 50 40 Natural Keratin Fibers (Hz) Feeding Rate of 20.6 18.3 10.1~12.5 Discontinuous Fibers (Hz) Rotational Speed of 60 50 40 Carding Machine (Hz) Flowing Rate of Airflow 3.3~5.3 2.6~2.9 1.9~2.1 (m/s) Feeding Distance (cm).sup.1 18 10 5 Feeding Height (cm).sup.2 25 18 10 Note .sup.1The feeding distance is the horizontal distance between the outlet of the feeding channel and the middle axis of the curtain of semi-molten meltblown fibers. Note .sup.2The feeding height is the vertical distance between the bottom edge of the outlet of the feeding channel and the die of the meltblowing machine.

(35) In the nonwoven fabrics manufactured according to the specifications and manufacturing parameters listed in the table 1, the weight ratios of the meltblown fibers, the discontinuous fibers, and the natural keratin fibers are listed in the following table 2.

(36) TABLE-US-00002 TABLE 2 Contents of Nonwoven Fabrics of Working Example 1-3 Working Working Working Example 1 Example 1 Example 1 Weight Ratio.sup.3 1.0:1.3:2.7 1.0:1.1:2.2 1.0:1.1:1.2 Note .sup.3The weight ratio is the weight of the meltblown fibers:the weight of the discontinuous fibers:the weight of the natural keratin fibers.

(37) The nonwoven fabrics of the working examples 4-5 and the comparative examples 1-3 were compared in the following table 3. The nonwoven fabrics of the working examples 4-5 were manufactured by the apparatus of FIG. 2. The nonwoven fabric of the comparative example 1 contained the meltblown fibers only. The nonwoven fabric of the comparative example 2 contained the meltblown fibers and the discontinuous fibers only. The nonwoven fabric of the comparative example 3 contained the meltblown fibers and the natural keratin fibers only. In the nonwoven fabrics of the working examples 4-5 and the comparative examples 1-3, the discontinuous fibers 110 were made of polyethylene terephthalate (PET), the natural keratin fibers 120 were 650 fill power down, and the meltblown fibers 130 were made of polypropylene (PP). Other specifications and manufacturing parameters of the working examples 4-5 and the comparative examples 1-3 were the same.

(38) TABLE-US-00003 TABLE 3 Comparison of Working Examples 4-5 and Comparative Examples 1-3 Base Weight Softness- (g/m.sup.2) Thickness (cm) Fluffy Rate Stiffness Average Uniformity Average Uniformity (cm.sup.3/g) (cm) Comparative 51.6 90% 0.38 78% 7.3 2.5 Example 1 Comparative 189.5 89% 1.58 95% 8.3 2.6 Example 2 Comparative 63.8 93% 1.52 91% 23.8 2.5 Example 3 Working 101.6 94% 2.96 97% 29.1 2.8 Example 4 Working 85.8 92% 1.55 94% 18.0 2.7 Example 5

(39) As listed in the table 3, the uniformities of the base weights of the nonwoven fabrics of the working examples 4-5 were larger than 90%, specifically from 92% to 94%. Since the nonwoven fabrics of the working examples 4-5 had the discontinuous fibers, the fluffy rates of the nonwoven fabrics of the working examples 4-5 were from 12 cm.sup.3/g to 30 cm.sup.3/g, specifically from 18.0 cm.sup.3/g to 29.1 cm.sup.3/g, and the softnesses-stiffnesses of the nonwoven fabrics of the working examples 4-5 were less than 3 cm, specifically from 2.7 cm to 2.8 cm. These data were better than that of the comparative examples 1-3.

(40) The nonwoven fabrics of the working example 6 and the comparative examples 4-6 were compared in the following tables 4-5. The nonwoven fabrics of the working example 6 were manufactured by the apparatus of FIG. 2. The nonwoven fabric of the comparative example 4 contained the meltblown fibers only. The nonwoven fabric of the comparative example 5 contained the meltblown fibers and the discontinuous fibers only. The nonwoven fabric of the comparative example 6 were 3M Thinsulate. In the nonwoven fabrics of the working example 6 and the comparative examples 4-6, the discontinuous fibers were made of polyethylene terephthalate (PET), the natural keratin fibers were 650 fill power down, and the meltblown fibers were made of polypropylene (PP). Other specifications and manufacturing parameters of the working example 6 and the comparative examples 4-6 were the same.

(41) TABLE-US-00004 TABLE 4 Comparison of Working Example 6 and Comparative Examples 4-6 Insulation Heat per Unit Heat Transfer Thermal Thermal Thickness Preservation Coefficient Resistance Resistance (CLO/cm) Rate (%) (W/m.sup.2 .Math. C.) (m.sup.2 .Math. C./W) ( F. .Math. h .Math. ft.sup.2/Btu) Comparative 0.94-1.3 65.3 0.0350 0.2026 1.1508 Example 4 Comparative 1.72 78.2 0.0317 0.1291 0.7333 Example 5 Comparative 1.7 60 0.0341 0.3471 1.9710 Example 6 Working 2.0-2.4 80.7 0.0310 0.0966 0.5485 Example 6

(42) TABLE-US-00005 TABLE 5 Comparison of Working Example 6 and Comparative Examples 4-6 Compressional Resilience (%) Diameter (m) Comparative 75% 0.9-3.3 (meltblown fibers) Example 4 Comparative 88% 0.9-3.3 (meltblown fibers) Example 5 15.3 (discontinuous fibers) Comparative 89% 1.7~6.0 (meltblown fibers) Example 6 25.6 (discontinuous fibers) Working 92% 0.9-3.3 (meltblown fibers) Example 6 15.3 (discontinuous fibers)

(43) As listed in the tables 4-5, since the nonwoven fabric of the working example 6 had down, in comparison with the comparative example 6, the insulation per unit thickness increases by from 17% to 41%, the heat preservation rate increases by 34%, and the compressional resilience increases by 3%.

(44) All the features disclosed in this specification (including any accompanying claims, abstract, and drawings) may be replaced by alternative features serving the same, equivalent or similar purpose, unless expressly stated otherwise. Thus, unless expressly stated otherwise, each feature disclosed is one example only of a generic series of equivalent or similar features.

(45) Any element in a claim that does not explicitly state means for performing a specified function, or step for performing a specific function, is not to be interpreted as a means or step clause as specified in 35 U.S.C. 112, 6th paragraph. In particular, the use of step of in the claims is not intended to invoke the provisions of 35 U.S.C. 112, 6th paragraph.