JPH1161625A - Non-woven fabric composite material and thermally fused molded product - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a non-woven fabric composite material exhibiting the characteristics of both a melt-blown non-woven fabric and a spun-bonded non-woven fabric, not limiting a raw material for the spun-bonded non-woven fabric on the composite fusion of the melt- blown non-woven fabric to the spun-bonded non-woven fabric, capable of easily and strongly performing the thermal fusion at a low temperature, and to provide a thermally fused molded product using the composite material and having an excellent thermal fusion strength. SOLUTION: This non-woven fabric composite material is obtained by thermally fusing (A layer) a spun-bonded non-woven fabric and (B layer) a melt-blown non-woven fabric of polyolefins containing 10-70 wt.% of a styrenic elastomer and having a fiber diameter of 0.1-10 μm to (C layer) a span-bonded non-woven fabric comprising the 0.5-10 denier filaments of one or more kinds of high melting point polymers selected from polyesters, polyamides and polyolefins, wherein the layer B is used as the central layer. The layer A comprises 0.5-10 denier conjugate filaments comprising a polyester component and a polyethylene component wherein the polyethylene component forms a part of the surface of the layer A and wherein the conjugated filaments are thermally fused with the polyethylene component. The composite materials are superposed in a state that the layers A of the composite materials are faced to each other, and subsequently thermally fusing the desired portions of the laminate to produce the molded product.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a nonwoven fabric composite material and a heat-sealed molded product using the same. More specifically, the present invention relates to a nonwoven fabric composite material capable of laminating and unifying a spunbonded nonwoven fabric and a meltblown nonwoven fabric and complementing and exhibiting the properties of the two nonwoven fabrics, and a heat-sealed molded product using the material. Although the nonwoven fabric composite obtained by the present invention is used in various industrial fields, it can be particularly effectively used for packaging materials, protective clothing, and the like.

[0002]

2. Description of the Related Art A melt-blown nonwoven fabric (hereinafter sometimes abbreviated as MB) has a very small single fiber diameter as a constituent fiber thereof, and a nonwoven fabric made of ultrafine fibers has a small opening diameter (pore size). Although it is used as a liquid or solid barrier layer and as a filter layer, it is also used in fields where it has a soft feel, but due to the weakness of its ultrafine fibers, It has the disadvantage that the strength of the nonwoven fabric is low, and fluffing and hair removal easily occur.

[0003] For this reason, as disclosed in Japanese Patent Publication No. 60-11148, a composite laminated and integrated with a strong spunbonded nonwoven fabric (hereinafter sometimes abbreviated as SB) has been proposed. There is a restriction in making a good composite integrated product by a heat fusion method that can reduce the cost, and both nonwoven fabrics are made of polypropylene (hereinafter sometimes abbreviated as PP), such as MB made of polypropylene and SB made of PP. In addition, a material that is at least lower in temperature and less thermally damaged at the time of heat fusion is selected as a combination of at least homogeneous materials. However, PP-MB and PP-SB as described above
In combination with the above, even if heat fusion can be performed at a relatively low temperature because of the PP material, the hydrophobicity of the non-woven fabric is high, and the molded article made of the composite non-woven fabric is, for example, packed with Daijako and made a dipping liquid. If the filter packaging bag is used as a filter packaging bag, the filter packaging bag does not easily sink into the liquid, and good soup stock extraction cannot be performed. That is, the above selection restricts the nonwoven fabric composite,
Therefore, its use is limited and inevitably restricted.

[0004]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned disadvantages, and there is no restriction on the SB material for forming a composite joint while exhibiting the characteristics of both MB and SB. It is another object of the present invention to provide an invention that can easily and firmly join the heat fusion at a low temperature.

[0005]

That is, the first aspect of the present invention comprises a polyester component and a polyethylene component, and the polyethylene component forms a part of the fiber surface.
Spunbond nonwoven fabric (layer A) consisting of 5 to 10 denier composite filaments and heat-sealed with the polyethylene component
And a polyolefin containing 10 to 70% by weight of a styrene-based elastomer, a melt blown nonwoven fabric (layer B) having a fiber diameter of 0.1 to 10 microns, and a polyester, polyamide or polyolefin selected from 0.5 to 10 denier. This is a nonwoven fabric composite material in which three layers of a spunbonded nonwoven fabric (layer C) composed of a high melting point long fiber of a kind or more components and a spunbonded nonwoven fabric (C layer) are heat-bonded with the B layer as a center layer.

Further, claim 2 of the present invention is claim 1
Is a molded product obtained by laminating the nonwoven fabric composite materials described in (1) in a state where the A layers face each other, and heat-sealing required portions thereof.

The nonwoven fabric composite material of the present invention comprises a three-layered composite material comprising a central layer (layer B) of a polyolefin containing 10 to 70% by weight of a styrene-based elastomer and having a fiber diameter of 0.1 to 10 μm. ) Has a great feature that strong thermal fusion without peeling between the upper surface A layer and the lower surface C layer can be performed at a low temperature. Of course, the characteristics of the MB central layer and the upper and lower surfaces A material that satisfies both the characteristics of the SB surface layer and the characteristics of the SB surface layer can be obtained. In this case, the material of the upper and lower SB surface layers is not restricted by the material of the MB central layer. In the nonwoven fabric composite material of the present invention, one of the sheets is folded with the layer A side facing the inside, or two sheets are overlapped with the layer A facing the inside and the required portions are heat-sealed. By doing, due to the surface low melting point characteristics of the A layer SB fiber,
Strong heat fusion at low temperature is possible, and due to the high melting point characteristics of C layer fiber, there is no damage at the time of heat fusion, and B layer does not come out to the surface and C layer is on the surface side. (Skin feel) is good, and it is strong against friction.

The styrene elastomer of MB forming the center B layer according to the present invention is, for example, Japanese Patent No. 25343.
No. 78 or a nonwoven fabric made of the polymer can be used. That is, as the styrene-based elastomer, a polymer block X mainly composed of 10 to 70% by weight of an aromatic vinyl compound and the following chemical formula 1
And a block copolymer composed of a polymer block Y mainly composed of a repeating unit represented by the following chemical formula 2 in the range of 0 to 20 mol%.

[0009]

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[0010]

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(However, in chemical formulas 1 and 2, any one or two of R ^{1 to} R ⁴ are a methyl group, and the rest are hydrogen atoms.)

Such a hydrogenated block polymer is obtained by hydrogenating a block copolymer consisting of a polymer block X mainly composed of an aromatic vinyl compound and a polymer block Y 'mainly composed of a conjugated diene compound. It is obtained by hydrogenating more than 80% of the aliphatic double bonds based on dienes.

As the aromatic vinyl compound, styrene is the most preferable in view of cost. Examples of the conjugated diene include 1,3-butanediene, isoprene, pentadiene, and hexadiene, and isoprene is most preferable.

The styrene content of the hydrogenated block copolymer ranges from 10 to 70% by weight. If the styrene content is less than 10% by weight, moldability and heat resistance are poor. If the styrene content exceeds 70% by weight, the stretchability and flexibility are reduced, and the adhesion to the A layer and the C layer cannot be obtained.

The hydrogenated block copolymer is
It is necessary that 80% or more, preferably 90% or more, of the isoprene double bond based on the conjugated double bond is hydrogenated. Below this range, thermal deterioration tends to occur during melt molding, and the weather resistance of the obtained nonwoven fabric is also deteriorated.

There are various polymer forms of the block copolymer, but a linear block body, particularly an ABA triblock, is preferred. These block copolymers can be obtained by anionic polymerization in a hydrocarbon solvent using an organic lithium compound or metallic sodium as an initiator. The hydrogenation reaction can be performed using a noble metal such as platinum or palladium, an organic nickel compound, an organic cobalt compound, or a composite catalyst of these compounds and another organic metal compound.

In order to prevent sticking between the obtained nonwoven fabrics, MB made of this kind of elastomer is usually used in a mixed composition in which a small amount of polyolefin is added to the elastomer. The purpose of this is to use MB of the elastomer,
Utilizing good heat-fusibility to SB, M
B is not intended to be stretchable. Therefore, in the present invention, the MB as the center B layer has a basic concept of adding the styrene-based elastomer to the polyolefin, and the mixing ratio of the styrene-based elastomer to be added is based on the total composition. Is preferably 10% by weight or more. If the proportion of the elastomer is less than 10% by weight, the resulting MB
Cannot exhibit heat-fusibility to SB, which is not preferable. However, when the styrene-based elastomer has a mixed composition exceeding 70% by weight, the MB becomes elastomer-rich and has high tackiness and adhesiveness, and is not so preferable from the viewpoint of production and operation of the MB. .

The SB forming the surface A layer in the present invention comprises a polyester component as a high melting point component and a polyethylene component as a low melting point component. SB consisting of 10 denier composite long fiber. This SB is made of a combination of a polyester component serving as a fiber core and a polyethylene component serving as a sheath, so that the nonwoven fabric has excellent tensile strength as compared with ordinary spunbond, and is easy to operate at low temperatures. In addition, strong thermal bonding is possible. This strong thermal bonding property makes it possible to obtain a strongly bonded molded article having excellent peeling resistance by making the A layers the innermost layers and heat-bonding them in a facing state. Things. However, when the fineness of the constituent fibers is less than 0.5 denier, the nonwoven fabric becomes unsatisfactory in terms of tensile strength, and when it exceeds 10 denier, the nonwoven fabric becomes unfavorably coarse and uneven.

For example, such SB is prepared by melt-extruding each component from a plurality of extruders, and combining both components from a composite spinneret so that the polyethylene component forms at least a part of the fiber surface. Typically, a core-sheath type composite fiber) is spun, the spun fiber is taken up by an air current pulling type device such as air soccer, and the fiber is collected together with the air current by a web collecting device such as a net conveyor, and then necessary. The web can be obtained by subjecting the web to a treatment such as fusing using a heating device such as heated air or a heated roll.

The SB forming the surface C layer in the present invention is:
The spunbonded nonwoven fabric is composed of high melting point long fibers of one or more components selected from 0.5 to 10 denier polyester, polyamide and polyolefin. This nonwoven fabric has a strong tensile strength due to its material and fiber fineness, and because of its fineness that does not reach ultrafineness, it has an excellent texture as the outermost layer surface material, and it has a fluffy state without cutting against friction etc. It won't be. In particular, if the surface C layer is made of SB made of polyamide, a molded article having an improved liquid wetting speed due to its material can be obtained.

The method of preparing the nonwoven fabric composite material of the present invention by integrating the three layers consisting of the layer A, the layer B and the layer C is as follows. Rolls, heat calender rolls, high-frequency welders, ultrasonic sealers, heat sealers, etc., are integrated by known heat-sealing means, or prepared in advance by A
While the layer nonwoven fabric or the C layer nonwoven fabric is guided to a collection conveyor of a melt blown spinning device, a melt-blown to be a B layer nonwoven fabric is directly spun on the nonwoven fabric,
Create a laminated nonwoven with A-layer nonwoven or C-layer nonwoven,
Thereafter, a method may be adopted in which another nonwoven fabric is integrated with the laminated nonwoven fabric by the above-mentioned heating and fusing means.

In order to construct the nonwoven fabric composite material of the present invention comprising a three-layer integrated product as, for example, a packaging bag, the A-layer nonwoven fabrics are laminated as innermost layers so as to be in a relative surface state. What is necessary is just to heat-integrate into a bag shape by the above-mentioned heat fusion means.

[0023]

EXAMPLES The nonwoven fabric composite material of the present invention and the heat-fused molded article comprising the same will be described below with reference to examples, but the present invention is not limited thereto.

Example 1: The following nonwoven fabrics were prepared as the nonwoven fabrics of the layers A to C. Layer A: “Elves” spunbond; weight 15 g / m ² [“Elves” is a trade name of Unitika Ltd., a spunbond nonwoven fabric made of a composite filament having a polyester core component and a polyethylene sheath component] B layer: polypropylene 80 Melt blown nonwoven fabric having a mixed composition of 20% by weight of “Septon” polymer and 20% by weight of “Septon” polymer; basis weight: 20 g / m ² [“Septon” is a trade name of Kuraray Co., Ltd.
A styrene-isoprene-styrene-type hydrogenated block copolymer having a styrene content of 27% by weight and a hydrogenation rate of 98%] C layer: polyamide spunbond; basis weight 15 g / m ²

Three layers of the above nonwoven fabric are layered in the order of layer A, layer B and layer C from above, and the temperature is 130.degree.
/ Cm was hot-pressed between the hot embossing roll and the flat roll to obtain a nonwoven fabric composite material of the present invention in which three layers of dot embossing having a compression area ratio of 25% were integrated.
This nonwoven fabric composite material has a vertical strength of 15.8 kg / 5c.
m, lateral strength was 4.6 kg / 5 cm.

This non-woven fabric composite material is folded so that the layer A is on the inside, and this is baked at a temperature of 200 ° C. and a pressure of 25 k.
g / cm to a heat sealer to form a bag with one side open, insert a zipper through this opening, and then heat-seal the opening between the heat sealers under the same conditions to obtain a vertical dimension of 20 cm. × A commercial dash bag having a width of 15 cm was produced.

Heat sealing in this bag making was extremely smooth. In addition, the heat sealing was complete, and there was no trouble that imperfect ones such as dusting powder falling out of the bag after a long operation operation. Furthermore, when this dashi bag is put into hot water, the surface is easily wetted and easily sinks in hot water.
It was possible to obtain a very good dashi juice liquid with less loss of the dashi powder fine particles.

Example 2: The following nonwoven fabrics were prepared as the nonwoven fabrics of the layers A to C. Layer A: “Elves” spunbond; basis weight 20 g / m ² Layer B: melt-blown nonwoven fabric composed of a mixed composition of 70% by weight of polypropylene and 30% by weight of “Septon” polymer; layer 30g / m ^{2 by} weight; C layer: polyester spunbond; 15 g / m ²

These nonwoven fabrics were laminated and hot-embossed in the same manner as in Example 1 to easily obtain a nonwoven fabric composite material of the present invention in which three layers were integrated and the dot-shaped compression area ratio was 9%. . This nonwoven fabric composite material was extremely excellent in texture. When this nonwoven fabric composite material was made into an envelope with its A side inside, it could be made very easily.

[0030]

As described above, the present invention makes use of the properties of MB and SB as well as the excellent heat-sealing properties of MB to improve the properties of MB.
It is possible to obtain a three-layer nonwoven fabric composite material which is strong and has excellent feeling without peeling between the B layer and the upper and lower SB layers. Further, the nonwoven fabric composite material can be formed into a package or a cover having excellent peeling strength by heat-sealing in a state where one of the SB layers is an inner surface layer facing each other.

Claims (2)

[Claims] 1. A spunbond nonwoven fabric comprising a polyester component and a polyethylene component, wherein the polyethylene component comprises a composite long fiber of 0.5 to 10 denier forming a part of the fiber surface, and which is heat-sealed by the polyethylene component. A
Layer), a polyolefin containing 10 to 70% by weight of a styrene-based elastomer, a melt-blown nonwoven fabric (layer B) having a fiber diameter of 0.1 to 10 μm, and a polyester, polyamide or polyolefin having a denier of 0.5 to 10 denier. A nonwoven fabric composite material obtained by heat-bonding three layers of a spunbonded nonwoven fabric (C layer) made of high melting point long fibers of one or more components with the B layer as a center layer. 2. A spunbond nonwoven fabric comprising a polyester component and a polyethylene component, wherein the polyethylene component comprises a composite continuous fiber of 0.5 to 10 denier forming a part of the fiber surface, and which is heat-sealed by the polyethylene component. A
Layer), a polyolefin containing 10 to 70% by weight of a styrene-based elastomer, a melt-blown nonwoven fabric (layer B) having a fiber diameter of 0.1 to 10 μm, and a polyester, polyamide or polyolefin having a denier of 0.5 to 10 denier. Three layers of a spunbonded nonwoven fabric (C layer) composed of one or more components of high melting point long fibers and a nonwoven fabric composite material obtained by heat-sealing the B layer as a center layer, and the A layers thereof A heat-sealed molded product obtained by stacking the parts facing each other and heat-sealing the required parts.