KR101268925B1 - Kapok Nonwoven Using Bicomponent Fiber and Manufacturing Method Thereof - Google Patents

Abstract

The present invention provides a nonwoven fabric prepared by mixing kapok fibers with thermoplastic composite fibers.
The kapok fiber nonwoven fabric of the present invention is free from scattering due to the cutting of the fiber, and is excellent in shape stability, and furthermore, excellent in sound absorption. Therefore, it can be used as a sound absorbing material of automobiles, ships, airplanes, etc., sound absorbing materials for building and various industrial, oil absorbent cloth, separators, insulation, bedding and bedding accessories, life-filled vests and all other filling materials.

Description

Kapok Nonwoven Using Bicomponent Fiber and Manufacturing Method Thereof}

The present invention relates to a kapok fiber nonwoven fabric and a method for manufacturing the same, and more particularly, to a kapok fiber nonwoven fabric having high morphological stability, sound absorption and thermal insulation by mixing the kapok fiber with a bicomponent thermoplastic composite fiber, and a method for manufacturing the same. will be.

Kapok fiber is a seed hair fiber of kapok tree, and its origin is Malaysia, and is mainly produced in Hawaii, Java, Philippines, Taiwan, and the like. The kapok fibers are hollow natural fibers having a fiber length of 8 to 32 mm, a thickness of 30 to 35, and a circular to oval cross section. The kapok fiber is characterized by its hollow shape, has a low density of 0.30 g / cc, and is about 1/5 of the light weight of cotton (density 1.54 g / cc), and is light and elastic in addition to gloss like silk. . In addition, it is a natural fiber that has a wool-level insulation and other characteristics such as sound absorption, oil absorption, antibacterial, deodorant, far-infrared radiation, etc., and is being developed.

However, since the kapok fiber has a short fiber length and a thin cell wall and can be easily cut during carding and the like, its use is limited to furniture, bedding fillers, and lifesaving fillers. In order to produce a kapok fiber with a nonwoven fabric or the like, it has been variously attempted to utilize it as a thermal insulation, sound absorption, and an oil absorption material.

For example, Patent Document 1 discloses a sound absorbing material using kapok fibers. However, the sound absorbing material is merely filled with the kapok fibers in a porous material without any processing.

Patent Document 2 discloses an example in which a nonwoven fabric prepared by blending a kapok fiber and a PP fiber in a 1: 1 manner is manufactured and used for oil removal, and Patent Document 3 discloses a kapok nonwoven fabric / thermoplastic or thermosetting resin / kapopp nonwoven fabric. A configured sound absorbing material is disclosed. However, the nonwoven fabrics still cannot completely solve the problems such as fiber cutting or scattering during the use of kapok fiber, and when the binder fiber of single component is used, the binder fiber is melted during thermal bonding to form a fiber shape. There is a problem that the air permeability is easily lowered and the mechanical properties are hardly improved. On the other hand, when the binder fiber of the composite fiber is used, it is possible to increase the bonding strength between the fibers in the nonwoven fabric without losing the form of the fiber by melting only the surface of the binder fiber, thereby improving the mechanical properties of the kapok nonwoven fabric without reducing the air permeability. There is such an advantage.

Thus, the present inventors confirmed that by bonding the kapok fibers using a thermoplastic composite fiber, it can be used as a sound absorbing material by remarkably improving the scattering of chopped fiber, which is a problem of the above-described prior art, or the shape stability of the manufactured nonwoven fabric. The invention has been completed.

U.S. Patent 6,338,395 Republic of Korea Patent Publication No. 2009-117136 Republic of Korea Patent Publication No. 2006-13468

An object of the present invention is to provide a nonwoven fabric having high form stability, sound absorption and thermal insulation by compressing the kapok fibers mixed with bicomponent thermoplastic composite fibers.

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

The kapok fiber nonwoven fabric of the present invention is characterized in that the kapok fibers are bonded by a bicomponent thermoplastic composite fiber.

The kapok fiber and the thermoplastic fiber length is preferably short fibers of 1 to 10mm.

The bicomponent thermoplastic composite fibers may have a side by side type, a core-sheath type, a sea-islands type, a segmented-pie type, or the like. It is preferably one or more selected from the group consisting of composite fibers having.

The weight ratio of the kapok fiber and the thermoplastic fiber is preferably 90:10 to 10:90.

Method for producing a kapok fiber nonwoven fabric of the present invention comprises the steps of cutting the kapok fiber and bicomponent thermoplastic composite fibers into short fibers of 1 to 10mm; Preparing a dispersion by mixing the kapok short fibers, thermoplastic short fibers and a surfactant with a dispersion medium; Forming a web using the paper machine using the dispersion; And hot pressing the web.

As the surfactant, one or more of cationic surfactant, anionic surfactant, nonionic surfactant, and amphoteric surfactant may be used.

The hot pressing is preferably calendering, double belt press, hot air bonding, infrared bonding, ultrasonic bonding, or the like.

The kapok fiber nonwoven fabric of the present invention is free from scattering due to the cutting of the fiber, and is excellent in shape stability, and furthermore, excellent in sound absorption. Therefore, it can be used as a sound absorbing material used in automobiles, airplanes, ships and other transports or indoor building materials.

1 is a scanning electron micrograph of the surface of the nonwoven fabric prepared in Example 2 of the present invention,
2 is a scanning electron micrograph of the surface of the nonwoven fabric prepared in Example 4. FIG.
FIG. 3 is a graph measuring changes in sound absorption coefficients according to frequency changes of the nonwoven fabrics of Examples 1 to 4 and Comparative Example 1. FIG.

The nonwoven fabric of the present invention is characterized in that it is prepared by mixing the kapok fibers with thermoplastic fibers.

The kapok fiber used in the nonwoven fabric of the present invention is a natural fiber obtained from the fruit of the kapok tree (Keiba pentantra, Ceiba pentantra), and its shape is hollow, low specific gravity, and has sound absorption characteristics. Also called Java fiber, the main origin of the kapok tree is Java, Sumatra, India, Thailand and the like. However, the kapok fiber used in the nonwoven fabric of the present invention may be used as it is a fiber collected in nature, it is preferable to use short fibers cut to a length of 1 ~ 10mm. If the length of the kapok fiber does not reach 1mm, the adhesion problem occurs, the strength is lowered, which is not preferable, if the length exceeds 10mm, there is a problem that the dispersion of the fiber occurs and the uniformity is lowered.

The two-component thermoplastic composite fiber serves to bind the constituent fibers with a low melting point or a softening point component layer. The bicomponent thermoplastic composite fibers for this purpose include side by side type, core-sheath type, sea-islands type and segmented-pie type. It is preferably at least one selected from the group consisting of composite fibers having a form. More preferably, at least one material selected from the composite fibers in which the material having a high melting point constitutes the core component and the material having a lower melting point or softening point than the core component constitutes the sheath component is preferred. The material constituting the bicomponent thermoplastic composite fiber is low melting point polyethylene terephthalate (LM-PET), polypropylene / polyethylene (PP / PE), PET / PE, rapid melting polyethylene terephthalate (Rapid melting PET, RM-PET) ).

On the other hand, the weight ratio of the kapok fiber and the bicomponent thermoplastic composite fiber is preferably 90:10 ~ 10:90. If the weight ratio of the thermoplastic fibers does not reach 10, the bonding strength between the constituent fibers is lowered and the morphological stability of the nonwoven fabric is lowered. Therefore, if the weight ratio of the thermoplastic fibers exceeds 90, it is difficult to express the inherent characteristics of the natural hollow kapok fibers. have.

Method for producing a kapok nonwoven fabric of the present invention comprises the steps of cutting the kapok fiber and bicomponent thermoplastic composite fibers into short kapok fibers of 1 to 10mm; Preparing a dispersion by mixing the kapok fiber with the composite fiber, the composite fiber, and the surfactant with a dispersion medium; And forming a web using the papermaking method using the dispersion. After the drying step may further comprise the step of hot pressing.

The kapok short fibers and the thermoplastic fibers in each step of the manufacturing method are as described above. On the other hand, the surfactant is used for the purpose of effectively dispersing short kapok fibers and binder fibers. Although it is possible to disperse short kapok fibers and binder fibers without adding a surfactant, the short kapok fibers and binder fibers can be dispersed quickly and effectively by adding a surfactant. Surfactants used for this purpose include cationic surfactants, anionic surfactants, nonionic surfactants and amphoteric surfactants.

Examples of cationic surfactants include alkylammoniums such as alkyltrimethylammonium or alkyltriethylammonium, alkyldimethylbenzylammonium salts, amine phosphate salts, etc., wherein alkylammoniums are represented by the formula C _n H _{2n +1} N (CH). ₃ ) ₃ X (wherein X is OH, Cl, Br, HSO ₄ or a combination of OH and Cl, n is an integer from 8 to 22) and the formula C _n H _{2n +1} N (C ₂ H ₅ ) ₃ X (wherein n is an integer of 12 to 18).

Anionic surfactants include alkyl sulfates (eg, formula C _n H _{2n +1} OSO ₃ Na (where n is 12 to 18)), alkylsulfonates (eg, C ₁₂ H ₂₅ C ₆ H ₄ SO ₃ Na), alkylcarboxylic acids (e.g., C ₁₇ H ₂₅ COOH, C ₁₄ H ₂₅ COOH), and also sulfates of linear or branched aliphatic alcohols and polyethoxylated derivatives of carboxylic acids ; Alkylbenzenes or alkylnaphthalene sulfonates and sulfates such as sodium octylbenzenesulfonate; Alkylcarboxylates such as dodecylcarboxylate; And alkali metal and (alkyl) ammonium salts of ethoxylated and polyethoxylated alkyl and aralkyl alcohol carboxylates.

Amphoteric surfactants include alanine-based, imidazolium betaine-based, amidepropyl betaine-based, aminodipropionate and the like.

Further, nonionic surfactants include poly (ethylene oxide), (octaethylene glycol) monododecyl ether (C ₁₂ EO ₈ ), (octaethylene glycol) monohexadecyl ether (C ₁₆ EO ₈ ), and poly (alkyl Lene oxide) -poly (propylene oxide) -poly (ethylene oxide) (PEO-PPO-PEO) or inverse (PPO-PEO-PPO).

In the method of manufacturing a kapok nonwoven fabric of the present invention, the two-component thermoplastic composite fiber is as described above.

Finally, in the kapok nonwoven fabric manufacturing method of the present invention is a step of hot pressing after the drying step. This is to help the unit kapok fibers constituting the nonwoven fabric to be adhered by the low melting point component of the composite fiber, there is no particular limitation in the method, it is sufficient as the usual heating, pressing means used in the art. Examples include calendering, double belt press, hot air bonding, infrared bonding, ultrasonic bonding, and the like.

Hereinafter, the present invention will be described in more detail with reference to Examples. The following examples are merely illustrative of the present invention, but the content of the present invention is not limited by these examples.

1. Manufacture of KPOP Nonwovens

<Examples 1 to 4>

A kapok nonwoven fabric bonded by thermoplastic fibers was prepared by a wet-laid method.

First, the compositions used in the experiment are as follows. Using kapok fiber (Indonesia), but was used to cut to a size of about 2-3mm. As the bicomponent thermoplastic composite fiber, LM-PET short fibers (Hubis, core-sheath type) having a length of 2-3 mm and PP / PE composite fiber short fibers (Woongjin Chemical, core-sheath type) having a length of about 6 mm were used. As the surfactant used for improving the dispersibility of the short fiber was used as the copolymer of polyethylene glycol and polypropylene glycol non-ionic surfactant (Sigma-Aldrich, product name Pluronic F127 ^ⓡ, average molecular weight 5,800; CAS 9003-11-6 ).

After dispersing the kapok fiber, the thermoplastic composite fiber, and the surfactant in the composition shown in Table 1 using water as a dispersion medium in the mixing bath, the mixture was stirred for 5 minutes at a stirring speed of 500 rpm to prepare a dispersion for forming a web.

After the web dispersion was added to the paper machine and stirred, the dispersion medium was removed to form a web and dried. At this time, the wire screen of the paper machine used the screen mesh of 120 #. Finally, the web was bonded in a double belt press process (temperature 170, speed 1.0 m / min) to prepare a nonwoven fabric.

&Lt; Comparative Example 1 &

Comparative Example 1 Example kapok fiber with a dispersion medium of water in Beth for mixing having a length of about 2 ~ 3mm, such as (Indonesian) and the copolymer (Sigma of polyethylene glycol and polypropylene glycol-Aldrich, product name Pluronic ^ⓡ F127 , An average molecular weight of 5,800; CAS 9003-11-6) After dispersing the surfactant, the mixture was stirred for 5 minutes at a stirring speed of 500 rpm to prepare a dispersion for forming a web.

After the web dispersion was added to the paper machine and stirred, the dispersion medium was removed to form a web and dried. At this time, the wire screen of the paper machine used the screen mesh of 120 #.

Finally, the web was prepared by spraying a spray adhesive onto the surface of the web and then attaching 30 g / m ² of polyester spunbond nonwoven fabric to the upper and lower layers. The comparative example is composed of 100% kapok fiber without using the composite fiber used as the binder fiber in the embodiment, it is characterized in that the surface is bonded with a spunbond nonwoven fabric.

number Composite fiber type Mixing ratio
(Kapok: composite fiber) weight
(g / m ² ) Example 1 LM-PET 70:30 94 Example 2 LM-PET 50:50 91 Example 3 PP / PE 70:30 105 Example 4 PP / PE 50:50 102 Comparative Example 1 - 100: 0 166

2. SEM evaluation

1) Evaluation method

In order to observe the surface of the kapok nonwoven fabric prepared from the Example was observed by magnification 500 times using a differential scanning electron microscope (JEOL, JSM-5510).

2) Evaluation result

1 is a scanning electron micrograph showing a 500 times magnification of a nonwoven fabric prepared in Example 2 of the present invention, and FIG. 2 is a scanning electron micrograph showing a 500 times magnification of a nonwoven fabric prepared in Example 4. FIG. As shown in the differential scanning electron micrograph, it can be seen that the surface of the thermoplastic composite fiber is melted by heat and adhered to the kapok fiber, and thus the nonwoven fabric prepared may have morphological stability.

3. Sound absorption evaluation

1) Evaluation method

Sound absorption evaluation is measured in the range of 400 ~ 5,000 Hz using a sound absorption tester (01dB-Metravib), the experiment is in accordance with the KS F 2814 standard.

2) Evaluation result

FIG. 3 is a graph measuring changes in sound absorption coefficients according to frequency changes of the nonwoven fabrics of Examples 1 to 4 and Comparative Example 1. FIG. In Fig. 3, 1K, 2K, 3.15K and 5K are sound absorption coefficients measured at 1000, 2000, 3150 and 5000 Hz, respectively.

As a result of evaluating the sound absorption characteristics in the kapok nonwoven fabric according to the present invention in the frequency range from 400 Hz to 5,000 Hz, the sound absorption coefficient tended to increase with increasing frequency. As in Examples 1 and 3, when the kapok fiber / composite fiber ratio is 7/3, the sound absorption performance is higher than that of Examples 2 and 4, which is 5/5, which is better because the content of the kapok fiber having a hollow is higher. Sound absorption performance was shown. On the other hand, it can be seen that the sound absorption performance is not significantly different depending on the type of the composite fiber used as the binder.

The nonwoven fabric of the present invention can be used as all the filling materials having the form stability, such as sound absorbing materials, construction and various industrial sound absorbing materials, oil absorbent fabrics, membranes, thermal insulation materials, bedding and bedding accessories, life jackets, such as automobiles, ships, airplanes.

Claims (12)

delete delete delete delete Kapok fibers and composite fibers selected from the group consisting of low melting polyethylene terephthalate (LM-PET), polypropylene / polyethylene (PP / PE), PET / PE and rapid melting polyethylene terephthalate (RM-PET) Cutting at least one bicomponent thermoplastic composite fiber into short fibers of 1 to 10 mm;
Preparing a dispersion by mixing the kapok short fibers, short fibers of a thermoplastic composite fiber, and a surfactant with a dispersion medium;
Forming a web using the paper machine using the dispersion; And
Method for producing a kapok fiber nonwoven fabric having excellent shape stability comprising the step of thermally bonding the web. delete 6. The method of claim 5, wherein the surfactant is a cationic surfactant, anionic surfactant, nonionic surfactant, or amphoteric surfactant. The method of claim 5, wherein the adhesion by heat is one or more selected from calendering, double belt press, hot air bonding, infrared bonding, ultrasonic bonding, and the like. Prepared by the method of claim 5, the kapok fiber is a low melting polyethylene terephthalate (LM-PET), polypropylene / polyethylene (PP / PE), PET / PE and rapid melting polyethylene terephthalate (Rapid melting PET, RM-PET) The kapok fiber nonwoven fabric having excellent shape stability, characterized in that bonded by at least one bicomponent thermoplastic composite fiber selected from the group consisting of. The nonwoven fabric of claim 9, wherein the kapok fibers are short fibers having a length of 1 to 10 mm. 10. The method of claim 9, wherein the bicomponent thermoplastic composite fiber is side by side type, core-sheath type, sea-islands type or segmented-pie. The kapok fiber nonwoven fabric, characterized in that the composite fiber having a type). The nonwoven fabric of claim 9, wherein the weight ratio of the kapok fiber to the thermoplastic fiber is 90:10 to 10:90.

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