JPH10273870A - Composite non-woven fabric and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the subject non-woven fabric, suitable for medical material, sanitary material, cloth or the like, by placing long-fiber webs, in which a low-melting and high-melting polymers are divided into extremely fine filaments, and short-fiber webs alternately to form a monolithic structure. SOLUTION: This non-woven fabric is composed of long-fiber and short-fiber webs placed alternately to form a monolithic structure. The long-fiber web is composed of a low-melting polymer and another type of polymer having a 30 to 180 deg.C higher melting point than the former, both being incompatible with each other and able to be formed into fibers, wherein these polymers form a continuous, single filament of divided type, two-component composite, which is further subdivided into extremely fine filaments. Examples of the combinations of these polymers include a polyolefin/polyamide. The long-fiber web is placed alternately with the short-fiber web containing potentially crinkling short fibers, to form the objective non-woven fabric of monolithic structure suitable for domestic and industrial goods, wherein the filaments are three- dimensionally entwined with those in the same web or other webs.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a composite nonwoven fabric obtained by laminating and integrating a long fiber web made of a fiber-forming polymer and a short fiber web mainly made of a fiber-forming polymer. Highly flexible, excellent in flexibility and having good filter performance and applicable to a wide range of applications including medical and hygiene materials, clothing, living related materials, industrial materials, and a method for producing the same. Things.

[0002]

2. Description of the Related Art Conventionally, various composite nonwoven fabrics in which short fiber webs are laminated on a base fabric have been disclosed. For example, JP-A-53-114975 and JP-A-53-12460
No. 1 discloses a nonwoven web or a melt blown cloth comprising a woven or knitted fabric as a base and made of splittable bicomponent conjugate short fibers.
Discloses a composite nonwoven fabric obtained by laminating ultrafine fiber webs obtained by a spinning method. However, the use of these composite nonwoven fabrics is limited to synthetic leather, and is extremely cost-effective and economically inferior. Further, JP-A-63-21354 discloses that a long fiber nonwoven fabric obtained by a spunbond method is used as a base fabric, and a long fiber present on one side or both sides is partially cut to form a fiber end. A composite nonwoven fabric is disclosed in which an end and a fiber obtained by laminating a short fiber web on a base fabric are entangled. However, this composite nonwoven fabric has a problem that the mechanical properties are deteriorated because the long fibers are partially cut, and the surface smoothness peculiar to the long fiber nonwoven fabric is impaired. Japanese Patent Publication No. 54-24506 discloses that a gas-permeable heat-sealing layer made of a thermoplastic fiber non-woven fabric and a gas-permeable non-heat-welding layer made of natural fibers and the like are laminated, and a heat-welding material is formed on the non-heat-welding layer. Are disposed intermittently, and a fused portion of the heat-welding substance and the heat-welding layer penetrates from both sides of the non-heat-welding layer, and has a structure in which the non-heat-welding layer is adhered and sandwiched. Has been proposed. However, although this laminated nonwoven structure has excellent water absorbability because natural fibers are laminated, it does not have a filter performance as is apparent from the purpose of improving the air permeability. In addition, the laminated nonwoven structure has a step of laminating a gas-permeable heat-sealing layer and a gas-permeable non-heat-welding layer when manufacturing the same, and a heat-sealing sheet layer for impregnation on the non-heat-sealing layer. A step of superposing and melting the heat-weldable substance and the heat-weldable layer by ultrasonic welding so as to permeate from both sides of the non-heat-weldable layer to exhibit a structure in which the non-heat-welded layer is adhered and sandwiched; From the viewpoint of the production technology, it is complicated and economically inferior from the viewpoint of the production technology, for example, requiring a step of peeling off the heat-weldable sheet while leaving the fused portion.

[0003]

Therefore, the present invention provides a
A composite non-woven fabric comprising a non-woven fabric composed of ultrafine split filaments composed of various types of fiber-forming polymers and a short-fiber non-woven fabric mainly composed of a fiber-forming polymer. A composite nonwoven fabric having high peel strength, excellent flexibility, and good filter properties;
An object of the present invention is to provide a method capable of efficiently manufacturing the same.

[0004]

Means for Solving the Problems The present inventors have made intensive studies to achieve the above object, and as a result, have reached the present invention. That is, the present invention has the following configuration as its gist.

The fiber-forming low-melting polymer is incompatible with the low-melting polymer and has a melting point lower than the melting point of the low-melting polymer by 3%.
An ultrafine splitting fiber composed of the low-melting-point polymer and the high-melting-point polymer developed by dividing a split-type two-component composite continuous single yarn comprising a fiber-forming high-melting-point polymer having a high melting point of 0 to 180 ° C. A long fiber web composed of a filament group and a short fiber web mainly composed of a fiber-forming polymer and composed of short fibers having latent crimpability are laminated, and the constituent fibers of the long fiber web are A composite nonwoven fabric, wherein constituent fibers of a long fiber web and a short fiber web and constituent fibers of a short fiber web are integrated by three-dimensional entanglement.

The fiber-forming low-melting polymer is incompatible with the low-melting polymer and has a melting point lower than the melting point of the low-melting polymer by 3%.
An ultrafine splitting fiber composed of the low-melting polymer and the high-melting polymer developed by dividing a split type two-component composite continuous single yarn comprising a fiber-forming high-melting polymer having a high melting point of 0 to 180 ° C. A long fiber web consisting of a group of filaments,
A short fiber web mainly composed of short fibers, which is made of a fiber-forming polymer, has latent crimping ability, and the latent crimp is revealed, is laminated, and the constituent fibers of the long fiber web are combined with each other. A composite nonwoven fabric, wherein constituent fibers of a fiber web and a short fiber web and constituent fibers of a short fiber web are integrated by three-dimensional entanglement.

The fiber-forming low-melting polymer is incompatible with the low-melting polymer and has a melting point lower than the melting point of the low-melting polymer by 3%.
Melt spinning of the split type two-component composite continuous single yarn group composed of a fiber-forming high melting point polymer having a high melting point of 0 to 180 ° C., and taking the composite continuous single yarn group using an air sucker, such as a screen conveyor Spread and deposited on the movable collecting surface to form a long fiber web, and the long fiber web is subjected to a partial thermocompression treatment on the composite continuous single yarn group using a partial thermocompression bonding apparatus to obtain a long fiber web, At least one surface of the long fiber web is mainly composed of a fiber-forming polymer, a short fiber web composed of short fibers having latent crimping ability is laminated, and then subjected to a high-pressure liquid flow treatment on the laminate, By making the constituent fibers of the long fiber web, the constituent fibers of the long fiber web and the short fiber web and the constituent fibers of the short fiber web three-dimensionally entangled, the laminate is integrated to obtain a composite nonwoven fabric, Duplicate Production of a composite nonwoven fabric characterized by performing a heat treatment at a temperature lower than the melting point of the polymer having the lowest melting point among the fiber-forming polymers that form the constituent fibers of the nonwoven fabric, so as to make latent crimps of the short fibers apparent. Method.

The fiber-forming low-melting polymer is incompatible with the low-melting polymer and has a melting point lower than the melting point of the low-melting polymer by 3%.
Melt spinning of the split type two-component composite continuous single yarn group composed of a fiber-forming high melting point polymer having a high melting point of 0 to 180 ° C., and taking the composite continuous single yarn group using an air sucker, such as a screen conveyor Spreading and depositing on the movable collecting surface to form a long fiber web, and applying a partial thermocompression treatment to the composite continuous single yarn group using a partial thermocompression bonding device to obtain a long fiber web, On at least one surface of the long fiber web, a short fiber web mainly composed of short fibers, which is made of a fiber-forming polymer, has latent crimping ability, and the latent crimp is realized, and then, By subjecting the laminate to high-pressure liquid flow treatment, the constituent fibers of the long fiber web, the constituent fibers of the long fiber web and the short fiber web, and the constituent fibers of the short fiber web are three-dimensionally entangled,
A method for producing a composite nonwoven fabric, comprising integrating a laminate.

In the method for producing a composite nonwoven fabric, as the long fiber web, the composite continuous single yarn present in a portion which is not thermocompression-bonded by the buckling treatment of the partially fiber-bonded long fiber web is divided and split. The composite characterized in that at least a part of the ultrafine split filament group composed of a low melting polymer or a high melting polymer is expressed, and the ultrafine split filament group uses a non-entangled long fiber web. Manufacturing method of nonwoven fabric.

In the method for producing a composite nonwoven fabric, as the long fiber web, a partially thermocompressed long fiber web is subjected to a high-pressure liquid flow treatment to divide the composite continuous single yarn present in a portion not thermocompressed. Characterized in that at least a part of the group of ultrafine split filaments composed of a low-melting polymer or a high-melting polymer is expressed, and that a long fiber web in which the group of ultrafine split filaments are three-dimensionally entangled is used. A method for producing a composite nonwoven fabric.

[0011]

Next, the present invention will be described in detail.
First, a long fiber web composed of a split type two-component composite continuous single yarn used in the present invention will be described. The split type two-component composite continuous single yarn, a fiber-forming low-melting polymer,
A fiber-forming high-melting polymer that is incompatible with the low-melting polymer. The reason that the low-melting polymer and the high-melting polymer are incompatible with each other is that the single yarn is easily split when subjected to impact.

The melting point of the fiber-forming high melting point polymer of the split type two-component composite continuous single yarn must be 30 to 180 ° C. higher than the melting point of the fiber-forming low melting point polymer. If the difference in melting point between the two is less than 30 ° C, not only the low-melting polymer but also the high-melting polymer will be softened and melted during thermocompression bonding using a partial thermocompression bonding apparatus, and the composite nonwoven fabric having flexibility Is not obtained, and in the subsequent split splitting step, both components are hardly split and split, and a target composite nonwoven fabric cannot be obtained. Conversely, if the difference in melting point exceeds 180 ° C., the low-melting-point polymer tends to undergo thermal deterioration when melt-spinning both polymers, which makes it difficult to produce a composite continuous single yarn, which is not preferable.

As a specific example of the split type two-component composite continuous single yarn, one having a cross section as shown in FIGS. 1 to 4 is preferable. In these, both components of the fiber-forming low-melting polymer and the fiber-forming high-melting polymer are both exposed on the surface of the fiber, and within the cross section of the fiber, one component is split by the other component. It is divided into possible forms.

The single-filament fineness of the split type two-component composite continuous single yarn is preferably 1 to 12 denier. When the single-fiber fineness is less than 1 denier, the discharge amount per single hole of the spinneret during melt spinning decreases, and the production amount tends to decrease. Increasing the number of holes makes the spinning process unstable. on the other hand,
If the single yarn fineness exceeds 12 denier, it tends to be difficult to cool the melt-spun yarn or take it off by air soccer, and to reduce the number of holes in the spinneret to promote cooling of the yarn. , The production volume decreases.

The split type two-component composite continuous single yarn is split at the boundary between the low-melting polymer and the high-melting polymer by the split splitting process, and the split filament made of the low-melting polymer and the high-melting polymer are separated. The split filament composed of a polymer is at least partially expressed. In the present invention, the single fiber fineness of the split filament that is expressed at least partially is preferably 0.8 denier or less, more preferably 0.05 to 0.8 denier, and still more preferably 0.1 to 0.5 denier. is there.
When the single yarn fineness is less than 0.05 denier, spinning is difficult in practice, and it is difficult to obtain a split type two-component composite continuous single yarn at low cost and rationally. In addition, there is a tendency that it is difficult to sufficiently perform split splitting. On the other hand, if it exceeds 0.8 denier, the obtained composite nonwoven fabric is inferior in flexibility and tends to have a rough and hard feeling, and the entanglement with the short fiber web is weakened, so that the delamination strength of the composite nonwoven fabric is increased. It tends to be inferior.

In the present invention, examples of the combination of the low melting point polymer and the high melting point polymer constituting the split type two-component composite continuous single yarn include polyolefin / polyamide, polyolefin / polyester and polyamide / polyester. These are representative examples, and other various combinations may be arbitrarily adopted.

Examples of the fiber-forming polyolefin polymer which can be used in the present invention include aliphatic α-monoolefins having 2 to 16 carbon atoms, for example, ethylene, propylene, 1-butene, 1-pentene, 3 -Methyl 1-butene, 1-hexene, 1-octene, 1-dodecene, 1-
There is a homopolyolefin or a copolymerized polyolefin of octadecene. Aliphatic α-monoolefins may contain other olefins and / or small amounts (up to about 10% by weight of polymer weight)
Other ethylenically unsaturated monomers, such as butadiene,
It may be copolymerized with similar ethylenically unsaturated monomers such as isoprene, 1,3-pentadiene, styrene, α-methylstyrene. Particularly, in the case of polyethylene, a copolymer obtained by copolymerizing propylene, 1-butene, 1-hexene, 1-octene or a similar higher α-olefin with up to about 10% by weight of the polymer weight is preferred because the fiber-forming property is improved.

Examples of the fiber-forming polyamide polymer usable in the present invention include nylon-4 and nylon-4.
6, Nylon-6, Nylon-66, Nylon-61
0, nylon-11, nylon-12, polymetaxylene adipamide (MXD-6), polyparaxylenedecaneamide (PXD-12), polybiscyclohexylmethanedecaneamide (PCM-12) or a monomer of these There is a copolyamide as a unit. Examples of fiber-forming polyester polymers that can be used in the present invention include terephthalic acid, isophthalic acid, phthalic acid, aromatic dicarboxylic acids such as 2,6-naphthalenedicarboxylic acid or adipic acid, sebacic acid and the like as an acid component. Aliphatic dicarboxylic acids or esters thereof, as the alcohol component ethylene glycol, diethylene glycol,
1,4-butanediol, neopentyl glycol,
It is a homopolyester or a copolyester synthesized from a diol compound such as 1,4-cyclohexanedimethanol, and the above-mentioned polyesters include paraoxybenzoic acid, 5-sodium sulfoisophthalic acid, polyalkylene glycol, pentaerythritol, Bisphenol A or the like may be added or copolymerized.

Examples of other fiber-forming polymers include:
For example, a vinyl polymer is used, and specifically, polyvinyl alcohol, polyvinyl acetate, polyacrylate, ethylene vinyl acetate copolymer, polyvinyl chloride, polyvinylidene chloride, or a copolymer thereof is used. . Further, a polyphenylene-based polymer or a copolymer thereof can also be used.

The fiber-forming low-melting polymer and the fiber-forming high-melting polymer include a matting agent, a pigment, a flameproofing agent, a deodorant, and a charging agent as long as the object of the present invention can be achieved. Optional additives such as an inhibitor, an antioxidant, an ultraviolet absorber, and an antibacterial agent may be added.

The long fiber web composed of the split type bicomponent composite continuous single yarn used in the present invention is generally produced by the following method. That is, spun by a conventionally known melt composite spinning method, using a conventionally known cooling device such as horizontal spraying or annular spraying, and cooled by spraying wind, and then generally using air soccer to reach a target fineness. As if towed and taken off. The towing speed is over 3000 m / min, especially 40
More than 00 m / min is more preferable because the dimensional stability of the nonwoven fabric is improved. The split-type two-component composite continuous single yarn discharged from air soccer generally consists of a screen after passing through a corona discharge area in a high-voltage field or through a frictional collision zone to be charged and spread. It is possible to obtain a long fiber web by spreading and accumulating on a moving deposition device such as a conveyor.

Next, the long fiber web is treated using a partial thermocompression bonding apparatus and partially thermocompression bonded. Partial thermocompression bonding means, for example, between a metal roll or embossing roll heated at a temperature equal to or lower than the melting point of the fiber-forming low-melting polymer and having an engraved pattern engraved on the surface, and a heated metal roll having a smooth surface. Means that the long fiber webs that are in contact with the engraved pattern are thermally pressed by using a so-called hot embossing roll or by using an ultrasonic fusing machine.

Each thermocompression bonding shape does not need to be circular, and any shape such as a rhombus, a triangle, and a T-shape may be appropriately selected. The area of each thermocompression bonding part is 0.1 to 1.0 mm ²
In the range of 4 to 80 points /
cm ² is good. Further, the ratio of the area of the entire press contact area to the total surface area of the long fiber web, that is, the press contact area ratio is preferably 5 to 30%, and more preferably 5 to 20%. If the pressed area ratio is less than 5%, the mechanical properties and dimensional stability of the composite nonwoven fabric tend to be poor. 30% conversely
When it exceeds, when laminating short fiber webs and performing entanglement treatment by liquid flow treatment, the delamination strength of both web layers tends to decrease due to a decrease in entangled portions.

The thermocompression bonding temperature (embossing roll temperature) in the thermocompression treatment is not higher than the melting point of the fiber-forming low-melting polymer, preferably 5 to the melting point of the fiber-forming low-melting polymer.
-30 ° C lower temperature. For example, if the processing is performed at a temperature higher than the melting point, the long fiber web sticks to the thermocompression bonding apparatus and the operability is remarkably deteriorated. When the thermocompression bonding temperature is a temperature close to the melting point of the fiber-forming low-melting polymer, thermocompression bonding becomes strong, so that the dimensional stability of the long fiber web is excellent, and in the subsequent high-pressure liquid flow treatment, During split splitting and entanglement integration of the composite continuous single yarn, the partial thermocompression bonding portion remains, and the ultrafine splitting filament group present in the non-thermocompression bonding portion is three-dimensionally entangled. Therefore, the obtained composite nonwoven fabric is
High elongation at break in the vertical and horizontal directions, excellent dimensional stability, and high mechanical strength. On the other hand, if the thermocompression bonding temperature is a temperature far from the melting point of the fiber-forming low-melting polymer, the partial thermocompression bonding section will be in a state of temporary thermocompression bonding in which the fiber form is left. At the time of split splitting and entanglement integration of single yarn, the partial thermocompression bonding part is peeled off and becomes fibrous,
The composite continuous single yarn group and the ultrafine split filament group can move freely and are more randomly three-dimensionally entangled.
Therefore, the obtained composite nonwoven fabric is excellent in flexibility and has high delamination strength.

The basis weight of the long fiber web is preferably about 100 g / m ² or less. If the basis weight exceeds 100 g / m ² , in the subsequent split splitting treatment, the split type two-component composite continuous single yarn tends to not be split sufficiently throughout the entire thickness of the long fiber web. That is, the split-type two-component composite continuous single yarn of the undivided fiber tends to remain at the center of the thickness of the long fiber web. However, even in such a case, it is still one of the embodiments of the present invention. Although the lower limit of the basis weight of the long fiber web is not particularly limited, it is 10 g / m ^{2 in} consideration of the formation of the obtained composite nonwoven fabric.
Up to a degree is preferred.

In the present invention, the short fiber web is laminated on at least one surface of the long fiber web and the constituent fibers are entangled and integrated. The long fiber web for laminating the short fiber web is a split-type web. Even in the case of a long fiber web which is partially thermocompressed and made of a component-based composite continuous single yarn, a length in which the two components forming the single yarn are split in advance and at least a part of the ultrafine split filament group is developed. It may be a fiber web.

As a method of splitting the two components forming a single yarn in advance on a partially fibrous web that has been partially thermocompression-bonded, and mechanically kneading the long fiber web, at least partially expressing a group of ultrafine split filaments. A method of processing (buckling treatment) to split the fibers and a method of applying a high-pressure liquid flow treatment to the long fiber web to give an impact and split the fibers are applied.

As a method of splitting by mechanical kneading (buckling), for example, a long fiber web is pushed into a push-type crimper through a buckling machine, that is, a pair of rolls, and splitting is performed by kneading. Fiber splitting, splitting by buckling the long fiber web through a pair of gear rolls, splitting the fiber by rubbing and bending the long fiber web between multiple guides, liquid splitting the long fiber web And a method of splitting the fiber by liquid flow.

The method of splitting by applying a high-pressure liquid flow treatment and giving an impact is the same as the water flow used when the long fiber web and the short fiber web of the present invention are entangled and integrated, and water is jetted. This refers to splitting and splitting the long fiber web by a water flow (high-pressure liquid flow) obtained by jetting the high-pressure liquid from the holes.

By preliminarily performing the split splitting treatment, in the subsequent lamination and integration entanglement treatment with the short fiber web, entanglement and integration of the constituent fibers can be performed with low energy of the high-pressure liquid flow. Therefore, the higher the splitting rate in the split splitting process to be performed in advance, the lower the energy of the high-pressure liquid flow can be to perform the confounding integration of the constituent fibers. Here, the splitting rate is determined by the following method. That is, any ten locations of the long fiber web are selected, and the cross section is magnified 100 times and a cross-sectional photograph is taken. Thirty filaments are randomly selected from one cross-sectional photograph, and the splitting rate is determined by the following equation. The same operation is performed for ten cross-sectional photographs, and the average value of the obtained values is defined as the splitting rate of the long fiber web. Splitting rate (%) = (30 / X) × 100 In the above formula, X is the total number of filaments composed of a low-melting-point polymer and a filament composed of a high-melting-point polymer, assuming that the splitting is complete. It is.

In particular, in the present invention, the splitting rate is preferably 60% or more in order to efficiently perform the subsequent entanglement and integration processing of the constituent fibers and obtain a composite nonwoven fabric having excellent delamination strength. It is more preferably at least 80%, further preferably at least 90%.

In the present invention, the long-fiber web on which the short-fiber web is laminated is subjected to splitting in advance in accordance with the specification of the high-pressure liquid flow energy in the subsequent lamination and confounding and the required performance of the composite nonwoven fabric. A long fiber web that has not been subjected to the treatment or a long fiber web that has been subjected to the splitting treatment in advance by the above various methods may be appropriately selected.

A long fiber web in which a group of ultrafine splitting filaments is developed in advance by a method of splitting and splitting by mechanical kneading (buckling) is used because the group of ultrafine splitting filaments is in an unentangled state. The degree of freedom of the filament is large, and the gap between the filaments is large, so that in the subsequent lamination and integration entanglement with the short fiber web, the constituent fibers of the short fiber web enter the group of ultrafine split filaments without restriction. Easy to get entangled. Therefore, lamination and entanglement integration by high-pressure liquid flow can be performed with low liquid flow energy, and the resulting composite nonwoven fabric has excellent flexibility and excellent delamination strength.

By the method of splitting by applying a high-pressure liquid flow and giving an impact, a long fiber web in which a group of ultra-fine splitting filaments is developed in advance has almost all split-type two-component composite continuous single yarn split. An ultra-fine split filament group in a confounding state is exhibited. Therefore, in the subsequent lamination and integration entanglement with the short fiber web, the high-pressure liquid flow treatment may be performed only for the purpose of entanglement and integration of the constituent fibers.

In the case of the long fiber web which has not been subjected to the splitting treatment in advance, in the subsequent lamination and integration entanglement with the short fiber web, the action of splitting and splitting of the split type two-component composite continuous single yarn has been demonstrated. This is performed simultaneously with the action of three-dimensionally confounding and integrating the fine filament groups or the split filament group with the short fibers or short fibers. Therefore, the energy of the high-pressure liquid flow in the confounding integration process is higher than the method using a long fiber web in which a group of ultrafine splitting filaments is expressed in advance, and the obtained composite nonwoven fabric is slightly inflexible. The process is simplified. In addition, the obtained composite nonwoven fabric has excellent filter performance that is densely entangled and integrated.

Next, a short fiber web made of the fiber-forming polymer used in the present invention and made of short fibers having latent crimpability will be described. The short fiber having latent crimpability of the present invention is a fiber that develops a spiral crimp by relaxation heat treatment. Examples of such short fibers having latent crimping ability include conjugate fibers in which fiber-forming polymers having different heat shrinkages are eccentrically arranged along the length direction of the fibers.
Examples of the composite form include a side-by-side type in which polymers having different heat shrinkages are arranged in a side-by-side manner along the fiber length direction, and an eccentric core-sheath type in which a core portion is eccentric. Considering the crimp development, the parallel type is preferable.

The cross section of the yarn is not limited to a round cross section, but may be a hollow cross section, a flat cross section, an irregular cross section, a multi-leaf cross section, or the like, depending on the required performance.

As a specific example of the cross section of the parallel type or the eccentric core / sheath type bicomponent conjugate short fiber, one having a cross section as shown in FIGS.

Any fiber-forming polymer having a different heat shrinkability for forming short fibers having latent crimping ability may be used as long as it can be melt-spun using an ordinary melt-spinning apparatus. As a combination of the fiber-forming polymers having different heat shrinkages, in the case of a parallel type bicomponent conjugate short fiber having a fiber cross-sectional shape, the two polymers need to be compatible with each other. That is, if they are incompatible, delamination occurs between the two components in the spinning step or the drawing step, resulting in not only impairing operability but also short fibers having no latent crimping ability.

The combination of the two polymers constituting the parallel type bicomponent continuous short fibers must be compatible. Therefore, a combination of the same polymer but of different viscosities or a combination of the same polymer and the same polymer may be used. A combination of copolymers of the polymer can be typically applied.

For example, in the case of a combination of different viscosities, a polyolefin-based polypropylene and a polypropylene having an MFR of about MFR30 and 30, and a polyester-based polyethylene terephthalate having a relative viscosity of about 1.5 and a relative viscosity of 1. About 3 polyethylene terephthalates are typical. In the case of a combination of the polymer and a copolymer of the polymer, a polyolefin-based polypropylene and a propylene-ethylene copolymer, and a polyester-based polyethylene terephthalate, ethylene terephthalate and isophthalic acid Is typical, but any combination may be used as long as it can exhibit a crimping function.

On the other hand, in the case of the eccentric core / sheath type bicomponent conjugate short fiber, the two polymers may be compatible with each other or may be incompatible. That is, even if the two components are incompatible, they are eccentric but have a core-sheath shape,
Troubles such as delamination do not occur in the spinning step or the drawing step.

As the combination of the two polymers constituting the eccentric core-sheath type bicomponent composite continuous short fiber, a combination of the same polymer having different viscosities or a combination of the polymer and a copolymer of the polymer is used. Any combination may be used as long as the polymer used in the above-described split type two-component composite continuous single yarn can be applied and a crimping function can be exhibited.

For example, when two types of polymers are compatible, it is preferable to use the same combination as in the case of the parallel type described above. When the two types of polymers are incompatible, polyester-based and polyamide-based, polyester-based and polyolefin-based, polyamide-based and polyolefin-based, and the like can be mentioned. At this time, it is preferable to position the low melting point polymer as the sheath component and the high melting point polymer as the core component when heat treating the composite nonwoven fabric of the present invention.

Examples of the polymer for forming short fibers that can be used in the present invention include fiber-forming polyolefin polymers, fiber-forming polyamide polymers, fiber-forming polyester polymers, and other fiber-forming polymers. As an example, the polymer applied to the split type bicomponent composite continuous continuous fiber described above can be used.

The parallel type or eccentric core-sheath type bicomponent composite short fiber used in the present invention is generally produced by the following method. That is, two kinds of polymer components having different heat shrinkages are spun by a conventionally known melt composite spinning method, cooled by a conventionally known cooling device such as a horizontal spraying or an annular spraying by a blowing air, and then an oil agent is applied. Then, it is wound on a winder as an undrawn yarn via a take-up roller. Take-up roller speed is 500m
/ Min to 2000 m / min. A plurality of wound undrawn yarns are drawn and aligned, and drawn between a group of rollers having different peripheral speeds by a known drawing machine. Next, the drawn tow is crimped by a press-type crimping device, and then cut into a predetermined fiber length to obtain short fibers. The heat setting may be performed at a temperature equal to or lower than the melting point of the polymer component used for the stretched tow, depending on the required use.

The parallel type or eccentric core-sheath type bicomponent conjugate short fiber obtained by the above method is subjected to heat treatment,
The latent crimping function of the fiber is manifested to exhibit bulkiness and flexibility. Among the polymers forming the side-by-side or eccentric core-sheath type bicomponent conjugate short fibers, the temperature is lower than that of the polymer having a low melting point, preferably 10 degrees below the melting point.
The heat treatment is preferably performed at a temperature lower than or equal to ° C. At this time, if the heat treatment is performed at a temperature equal to or higher than the melting point of the polymer having a low melting point among the polymers forming the side-by-side or eccentric core-sheath type bicomponent conjugate short fibers, the operability in the heat treatment step is significantly impaired. Or, the obtained composite nonwoven fabric is extremely poor in bulkiness and flexibility.

The heat treatment for realizing the latent crimping function of the fiber may be carried out at the stage of the short fiber web before compounding with the long fiber web, or after the compounding and integration of the long fiber web. Good. However, it goes without saying that the composite nonwoven fabric of the present invention has a latent crimping function, and also includes a composite nonwoven fabric having short fibers as constituent fibers that have not yet sufficiently manifested the crimp. .

The heat treatment machine to be used is preferably a machine having a mechanism such as a shrink dryer (manufactured by Kotobuki Kogyo Co., Ltd.) that does not apply tension during heat treatment, but is not particularly limited as long as the object of the present invention is achieved.

The short fiber web used in the present invention may be made of natural fibers such as cotton, wool, linen, silk and / or rayon according to the required properties such as imparting water absorption or imparting high gloss. Short fibers composed of recycled short fibers such as
Cotton may be mixed in a range of less than 30% by weight.

The basis weight of the short fiber web is preferably about 100 g / m ² or less. If the basis weight exceeds 100 g / m ² , a large high-pressure liquid flow energy is required in the entanglement treatment of the long fiber web and the short fiber web. Further, the use of the obtained composite nonwoven fabric is limited. The lower limit of the basis weight is not particularly limited, but may be about 10 g / m ² .

As the short fiber web, a web having a predetermined basis weight can be produced by using a card method, an air lay method or the like.
In the card method, a carding machine can be used to variously select the degree of arrangement of the constituent fibers according to the use of the composite nonwoven fabric. For example, as an arrangement pattern of the constituent fibers of the short fiber web, a parallel web in which the constituent fibers are arranged in one direction,
Examples of the web include a web in which parallel webs are cross-laid, a random web in which constituent fibers are randomly arranged, and a semi-random web in which both are moderately arranged.

According to the present invention, the long fiber web (partially thermocompressed long fiber web composed of a split type two-component composite continuous single yarn or a two-component forming the single yarn in advance is divided and split into ultrafine fibers. A high-pressure liquid flow treatment is applied to a laminate obtained by laminating a short fiber web on at least one surface of a long fiber web in which at least a part of a split filament group is expressed, and the constituent fibers of the long fiber web and the long fiber web and the short fiber web are processed. Is a composite nonwoven fabric in which the constituent fibers of the above and the constituent fibers of the short fiber web are three-dimensionally entangled and integrated. Here, the constituent fibers of the long fiber web refer to a split type two-component composite continuous single yarn and a group of ultrafine split filaments developed from the composite continuous single yarn.

This laminated body is obtained by laminating a short fiber web on at least one surface of a long fiber web, and even when laminating a short fiber web on both surfaces of a long fiber web,
A long fiber web may be laminated on both sides of a short fiber web, and may be appropriately selected in accordance with the use and performance of the composite nonwoven fabric.

Next, the high-pressure liquid flow processing method will be described in detail. As the high-pressure liquid flow device, for example, a hole diameter of 0.05 to 1.
Injection holes of 5 mm, especially 0.1 to 0.4 mm, having a hole interval of 0.
A large number of devices arranged in a single row or a plurality of rows with a size of 05 to 5 mm are used. A water stream, ie, a high-pressure liquid stream, obtained by jetting at a high pressure from the jet holes is jetted, and collides with the laminate placed on the porous support member. The undivided split-type bicomponent composite continuous yarn develops an ultrafine split filament by the impact of the high-pressure liquid flow, and the ultrafine split filaments group generated by the splitting is an ultrafine split filament group or ultrafine split filaments. The filament group and the short fibers or short fibers are three-dimensionally entangled and integrated.

The arrangement of the injection holes is arranged in a row in a direction perpendicular to the traveling direction of the laminate. As a high pressure liquid flow,
Room temperature or hot water can be used. The distance between the injection hole and the laminate is preferably 10 to 150 mm. If this distance is less than 10 mm, the formation of the composite nonwoven fabric obtained by this treatment is disturbed, while the distance is 1 mm.
If it exceeds 50 mm, the impact force when the liquid stream collides with the laminate tends to be low, so that split splitting and entanglement integration tend not to be sufficiently performed.

The processing pressure of the high-pressure liquid flow is controlled by the production method and the required performance of the nonwoven fabric, but generally, a high-pressure liquid flow of 20 to 200 kg / cm ² G is preferably ejected. In addition, depending on the basis weight of the web to be processed, etc., within the range of the above-mentioned processing pressure, if the processing pressure is low, a composite nonwoven fabric which is bulky and excellent in flexibility can be obtained. It is possible to obtain a composite nonwoven fabric which is densely entangled and has excellent filter performance without delamination. If the pressure of the high-pressure liquid flow is less than 20 kg / cm ² G, split splitting and entanglement unification are not sufficiently performed, and the obtained composite nonwoven fabric is inferior in delamination strength. Can not. Conversely, if the pressure of the high-pressure liquid stream exceeds 200 kg / cm ² G, the non-woven fabric obtained by cutting the constituent fibers tends to have fluff on the surface in a severe case due to impact by water pressure, which is not preferable. .

As the porous support member for supporting the laminate used for performing the high-pressure liquid flow treatment, for example, 2
There is no particular limitation as long as the high-pressure liquid flow penetrates the laminate, such as a mesh screen or a perforated plate made of a wire mesh or a synthetic resin of 0 to 200 mesh.

After the high-pressure liquid flow treatment is performed from one side of the laminate, the entangled laminate is subsequently inverted and subjected to the high-pressure liquid flow treatment, whereby the composite nonwoven fabric which is densely entangled on both sides is integrated. Can be obtained depending on the use of the composite nonwoven fabric, and may be applied to those having a large number of laminations and those having a large basis weight of the laminate.

After the high-pressure liquid flow treatment, excess moisture is removed from the laminated body after the treatment. When removing the excess moisture, a known method can be adopted. For example, the excess water is mechanically removed to some extent using a squeezing device such as a mangle roll, and the remaining water is subsequently removed using a drying device such as a suction band type hot air circulation dryer.

As described above in detail, the composite nonwoven fabric of the present invention is obtained by laminating a long fiber web and a short fiber web made of a two-component composite continuous single yarn, and using a high-pressure liquid flow treatment device to densely combine the two webs. It is a composite nonwoven fabric that is entangled and integrated. Since the two-component composite continuous single yarn is divided to exhibit a group of ultrafine splitting filaments, the long fiber web has an irregular cross-section such as a wedge or a flake, or a fiber having a very small fineness. Due to the presence of this group of ultrafine splitting filaments, the entanglement in high-pressure liquid flow treatment is excellent, the entanglement becomes a stable composite nonwoven fabric that is difficult to unwind, and the delamination strength with the short fiber web is excellent.

In addition, a fiber having latent crimping ability is used as the short fiber, and this fiber exhibits a bulky property because it develops a spiral crimp when the crimp becomes apparent. Therefore, the short fiber web side on which the latent crimp has become apparent has excellent bulkiness and has a large void in the thickness direction.

In the composite nonwoven fabric of the present invention, the higher the splitting ratio, the better the flexibility and the entanglement of the composite nonwoven fabric and the more excellent the delamination strength. The splitting rate in the composite nonwoven fabric may be appropriately selected according to the use of the composite nonwoven fabric. For example, when used as an industrial wiper or the like, the splitting rate is about 30%. When used as a household wiper for wiping glasses or mirrors, the splitting rate is about 50%. When used as a filter cloth, the splitting rate is about 70%. % Or more.

The composite nonwoven fabric of the present invention is used for medical and hygiene materials,
It is suitable for various fields such as clothing, living related materials, industrial materials and the like. For example, as an example, it is suitable to be used for wiping with a wiper or the like. That is, the composite nonwoven fabric is wiped off on the long fiber web surface, dirt and the like are wiped off at the sharp edge portion in the irregular cross section of the ultrafine split filament group, moisture is included in the composite nonwoven fabric by capillary action, and the short fiber web side A large void can contain a lot of moisture, wiped dust, and the like.

In the high-pressure liquid flow treatment, the pressure of the liquid flow is appropriately selected, and the composite nonwoven fabric of the present invention in which the constituent fibers are tightly and tightly entangled has excellent filter performance. It is suitable for use as a filter for diatomaceous earth filtration, for removing particles from well water, and for filtering cloth for iron removal. That is, first, coarse particles and coarse dust are removed on the short fiber web side having a large inter-fiber void in the composite nonwoven fabric, and then fine particles and fine dust that cannot be completely filtered are removed on the short fiber web side by a long fiber web having a small inter-fiber void. Can be removed on the side. Therefore, the composite nonwoven fabric of the present invention is a single nonwoven fabric, and can be separately collected according to the size of the object to be filtered, so that excellent filter performance can be maintained over a long period of time, and a filter cloth having a long filter life can be maintained. Can be used as

[0066]

EXAMPLES Next, the present invention will be described more specifically based on examples, but the present invention is not limited to these examples. In the examples, the measurement of each characteristic value was performed by the following method.

(1) Melting point of polymer (° C.): The maximum of the melting endothermic peak measured at a heating rate of 20 ° C./min using a DSC-2 type differential scanning calorimeter manufactured by PerkinElmer. The temperature giving the value was taken as the melting point.

(2) Relative viscosity of polyester (a): A mixture of phenol and tetrachloroethane in an equal weight was used as a solvent, and 0.5 g of a sample was dissolved in 100 cc of the solvent.
It was determined by a conventional method at 0 ° C.

(3) Fineness (denier) after splitting the fibers constituting the long fiber web: The cross-sectional area was calculated from the shape and dimensions of the electron micrograph, and the density was corrected.

(4) Tensile strength of nonwoven fabric (kg / 5cm
Width): The maximum tensile strength was measured from a test piece having a width of 5 cm and a length of 10 cm according to the strip method described in JIS L-1096.

(5) Softness (g) of nonwoven fabric: width 5 cm,
A test piece with a length of 10 cm is bent laterally into a cylindrical object,
Each of the joined ends was used as a bending resistance measurement sample.
The sample was compressed in the transverse direction at a compression rate of 5 cm / min using a constant-speed extension-type tensile tester, and the average of the obtained maximum load values was defined as the softness of the nonwoven fabric.

(6) Delamination strength of nonwoven fabric (g / 5 cm)
Width): A test piece having a width of 5 cm and a length of 10 cm was placed in the longitudinal direction of the composite nonwoven fabric using a constant-speed stretching type tensile testing machine, and the ends of the long fiber web layer and the short fiber web layer were respectively attached to the chucks of the testing machine. The average value of the load values when sandwiched and peeled at a pulling rate of 10 cm / min was defined as the delamination strength of the nonwoven fabric.

(7) Water absorption (mm / 10 minutes) of nonwoven fabric:
The measurement was carried out according to the birec method described in JIS L-1096.

Example 1 As a fiber-forming low-melting polymer of fibers constituting a long-fiber web, the melting point was 128 ° C. and ASTM-D-1238.
A polyethylene polymer having a melt index value of 25 g / 10 minutes obtained by the method (E) is used, and a polyethylene-terephthalate having a melting point of 258 ° C. and a relative viscosity of 1.38 as a fiber-forming high-melting polymer. A polymer was used. Then, using a composite spinneret in which the polyethylene cross-section has a total length of 7 with the polyethylene polymer forming the core in the composite form shown in FIG. 1, the composite ratio of the polyethylene polymer and the polyethylene terephthalate polymer is determined by weight. It was extruded at a discharge ratio of single hole = 1.2 g / min. After cooling the spun yarn, the yarn is taken out by air soccer at a speed of 4500 m / min, spread by a known spreader, collected and deposited on a moving collecting surface to form a long fiber web, Point pattern of long fiber web with hot embossing roller, processing temperature 120
Perform partial thermocompression bonding under the condition of ℃, pressure contact area ratio 10%,
A long fiber web having a basis weight of 30 g / m ² was obtained. The fineness of the split type two-component composite continuous single yarn collected from the fiber assembly was 2.4 denier.

The obtained long fiber web was subjected to a splitting treatment of a polyethylene polymer and a polyethylene terephthalate polymer using a buckling machine (Microcreper, manufactured by Microx Corporation). When the long fiber web after the splitting treatment was observed with a microscope, the ultrafine splitting filament made of a polyethylene polymer and the ultrafine splitting filament made of a polyethylene terephthalate polymer were each in an unentangled state, and the splitting rate was 92%. there were. The fineness of the ultrafine split filament made of polyethylene polymer is 1.
The fineness of the ultrafine splitting filament which was 2 denier and was made of a polyethylene terephthalate polymer was 0.2 denier.

On the other hand, as a short fiber web, the cross section of the yarn is shown in FIG.
A bicomponent short bicomponent fiber composed of a polypropylene polymer and a polypropylene copolymer was prepared in the composite form shown in (1).
That is, a polypropylene polymer having a melting point of 162 ° C. and a melt flow rate value of 30 g / 10 minutes measured by ASTM D1238 (L), and a melting point of 138 ° C. and ASTM D1238.
Using a polypropylene copolymer obtained by randomly copolymerizing 96% by weight of propylene and 4% by weight of ethylene with a melt flow rate value of 10 g / 10 measured in (L), as shown in FIG. From the composite spinneret, the composite ratio was extruded at a weight ratio of 1: 1 with a single hole discharge rate of 0.56 g / min. After the spun yarn was cooled and the finishing oil was applied, it was wound up as an undrawn yarn via a take-up roll having a take-up speed of 1000 m / min. Next, a plurality of the obtained undrawn yarns are drawn and aligned to form a tow. After drawing at a draw ratio of 2.3 using a known drawing machine, crimping is performed by a press-in type crimping device. Then, the fiber was cut to a fiber length of 51 mm to obtain short fibers of 2.4 denier. A short fiber web having a basis weight of 20 g / m ² was prepared using a random card machine using the short fibers.

Next, a short fiber web was laminated on one surface of the long fiber web which had been subjected to the split splitting processing in advance, and was loaded on a 50-mesh wire net and subjected to a high-pressure liquid flow treatment. The high-pressure liquid flow treatment uses a high-pressure liquid flow treatment apparatus in which injection holes having a hole diameter of 0.12 are arranged with a hole area of 0.62 mm, and a liquid flow pressure of 80 kg / cm ² G from a position 50 mm above the laminate.
Under the conditions described above, from the short fiber web side. The obtained composite was subjected to removal of excess moisture and drying treatment to obtain a composite nonwoven fabric having a basis weight of 50 g / m ² .

The obtained composite nonwoven fabric was subjected to a heat treatment at a treatment temperature of 115 ° C. using a shrink dryer to express the crimps of the constituent fibers of the short fiber web, thereby obtaining the composite nonwoven fabric of the present invention.

Example 2 In Example 1, 80% by weight of a parallel type bicomponent conjugate short fiber of the same polypropylene polymer and polypropylene copolymer as in Example 1 was used as the short fiber web, and the average single fiber fineness was 1%. 0.5 denier, 20% by weight of a cotton fiber having an average fiber length of 25 mm was mixed, and the basis weight was adjusted in the same manner as in Example 1 except that a short fiber web having a basis weight of 20 g / m ² was used with a random card machine. Of 50 g / m ² was obtained.

Example 3 As a short fiber web, an eccentric core-sheath type bicomponent composite short fiber of a polypropylene polymer and a polypropylene copolymer was prepared in a composite form having a yarn cross section shown in FIG.

That is, using the same polypropylene polymer and polypropylene copolymer as in Example 1, an eccentric core such that the polypropylene polymer is disposed in the core and the polypropylene copolymer is disposed in the sheath as shown in FIG. The mixture was extruded from the sheath-type two-component composite spinneret at a composite ratio of 1: 1 by weight and a single hole discharge rate of 0.61 g / min. After cooling the spun yarn and applying the finishing oil, the take-up speed is 1000
It was wound up as an undrawn yarn via a take-up roll of m / min. Next, a plurality of the obtained undrawn yarns are drawn and aligned to form a tow, and after drawing at a draw ratio of 2.5 using a known drawing machine, crimping is performed by a press-in type crimping device. Then, the fiber was cut to a fiber length of 51 mm to obtain short fibers of 2.4 denier. A short fiber web having a basis weight of 20 g / m ² was prepared using a random card machine using the short fibers.

Next, a short fiber web was laminated on one side of the long fiber web similar to that in Example 1 partially split, and subjected to a high-pressure liquid flow treatment under the same conditions as in Example 1 to give a basis weight of 50.
g / m ² was obtained. The obtained composite nonwoven fabric was subjected to a heat treatment under the same conditions as in Example 1, and the basis weight was 50 g /
to obtain a composite nonwoven m ^2.

Example 4 As the long fiber web, the same polyethylene polymer and polyethylene terephthalate polymer as in Example 1 were used, and the yarn cross section was as shown in FIG. And the composite ratio of the polyethylene polymer and the polyethylene terephthalate polymer was set to 1: 1 by weight and extruded at a single hole discharge rate of 1.12 g / min. After cooling the spun yarn, the yarn is taken out by air soccer at a speed of 4200 m / min, spread by a known spreader, collected and deposited on a moving collecting surface to form a long fiber web, The long fiber web was subjected to partial thermocompression bonding under the conditions of a point pattern, a processing temperature of 120 ° C., and a press contact area ratio of 10% using a hot emboss roller to obtain a long fiber web having a basis weight of 30 g / m ² . The fineness of the split type two-component composite continuous single yarn collected from the fiber assembly was about 2.4 denier.

Next, the long fiber web was subjected to a splitting treatment of a polyethylene polymer and a polyethylene terephthalate polymer by using a buckling machine (Microcreper, manufactured by Microex Corporation). Observation of the long fiber web after splitting with a microscope revealed that it was an ultrafine splitting filament made of polyethylene polymer and polyethylene terephthalate.
Each of the ultrafine splitting filaments made of the terpolymer was in an unentangled state, and the splitting rate was 85%. The fineness of the ultrafine split filament made of a polyethylene polymer and that of the ultrafine split filament made of a polyethylene terephthalate polymer were each 0.2 denier.

On the other hand, as a short fiber web, a basis weight of 20 parallel type bicomponent conjugate short fibers composed of the same polypropylene polymer and polypropylene copolymer as in Example 1 was used.
g / m ² were prepared.

Next, a short fiber web was laminated on one side of the partially split long fiber web and subjected to high-pressure liquid flow treatment under the same conditions as in Example 1 to obtain a composite nonwoven fabric having a basis weight of 50 g / m ^2. Was. Further, the obtained composite nonwoven fabric was subjected to a heat treatment under the same conditions as in Example 1 to obtain a composite nonwoven fabric of the present invention.

Example 5 In Example 1, a long fiber obtained by subjecting a long fiber web subjected to a partial thermocompression bonding treatment to a polyethylene polymer and a polyethylene terephthalate polymer by a high-pressure liquid flow treatment to split the fiber. A composite nonwoven fabric having a basis weight of 50 g / m ² was obtained in the same manner as in Example 1 except that the web was used.

That is, a long-fiber web subjected to a partial thermocompression treatment is loaded on a 100-mesh wire net, and a high-pressure liquid flow treatment apparatus in which injection holes having a hole diameter of 0.12 are arranged with a hole area of 0.62 mm is provided. The treatment was performed under the conditions of a liquid flow pressure of 50 kg / cm ² G from a position 50 mm above the laminate. When the long fiber web after the splitting treatment was observed with a microscope, the ultrafine splitting filaments composed of polyethylene polymer and the ultrafine splitting filament composed of polyethylene polymer and the ultrafine splitting filament composed of polyethylene terephthalate polymer and polyethylene terephthalate weight The ultrafine split filaments made of the union were in an entangled state, and the split rate was 85%. A composite nonwoven fabric having a basis weight of 50 g / m ² was obtained under the same conditions as in Example 1 with the short fiber web, high-pressure liquid flow treatment conditions, and heat treatment conditions.

Example 6 The basis weight was changed in the same manner as in Example 1 except that the long fiber web which had not been subjected to the split splitting treatment and had been subjected to the partial thermocompression bonding was used. Is 50
g / m ² was obtained. When the obtained composite nonwoven fabric was observed with a microscope, the splitting rate of the long fiber web was 72.
%Met.

Comparative Example A single-phase continuous fiber was prepared using the same polyethylene terephthalate as in Example 1. That is, a single-phase spinneret having a round yarn cross section was used, and the single-hole discharge amount was 1.33 g /
Extruded in minutes. After cooling the spun yarn, the yarn is taken out by air soccer at a speed of 5000 m / min, opened by a known opening device, collected and deposited on a moving collecting surface to form a long fiber web, Point pattern of long fiber web with hot emboss roller, processing temperature 240 ° C, pressure contact area ratio 10
% Thermocompression bonding under the condition of%, and the basis weight is 30 g / m.
^Two long fiber webs were obtained. The single-phase continuous fiber was 2.4 denier.

On the other hand, as a short fiber web, single-phase short fibers having a round cross section were prepared. That is, using the same polyethylene terephthalate used in Example 1, a single-phase spinneret having a round yarn cross section was extruded at a single hole discharge rate of 0.71 g / min. After the spun yarn was cooled and the finishing oil was applied, it was wound up as an undrawn yarn via a take-up roll having a take-up speed of 1000 m / min. Subsequently, a plurality of the obtained undrawn yarns are drawn and aligned to form a tow, and after drawing at a draw ratio of 2.9 using a known drawing machine, crimping is performed by a press-in type crimping device. The fiber was cut to a fiber length of 51 mm to obtain 2.4 denier polyethylene terephthalate short fibers. Using the short fibers, a short fiber web having a basis weight of 20 g / m2 was prepared using a random card machine. Next, a laminate entanglement treatment was performed under the same short fiber and lamination conditions as in Example 1 to obtain a composite nonwoven fabric having a basis weight of 50 g / m ² . Table 1 shows the physical properties of the composite nonwoven fabric.

The physical properties of the composite nonwoven fabrics and nonwoven fabrics obtained in Examples 1 to 6 and Comparative Example were measured and are shown in Table 1.

[0093]

[Table 1]

As is clear from Table 1, Example 1 shows that a two-component composite continuous single yarn composed of a polyethylene polymer and a polyethylene terephthalate polymer was divided into short fibers by a buckling treatment beforehand. Since it was a composite nonwoven fabric obtained by laminating webs and performing entanglement treatment using a liquid flow treatment device, it was excellent in all of tensile strength, delamination strength, and flexibility.

In Example 2, a two-component composite continuous single yarn comprising a polyethylene polymer and a polyethylene terephthalate polymer was split and split in advance by a buckling treatment. Since a short fiber web consisting of a blend of cotton with a parallel type bicomponent composite short fiber and cotton is used, tensile strength, peel strength,
It was excellent in flexibility and also excellent in hygroscopicity.

In Example 3, an eccentric core-sheath type two-component composite short yarn was added to a long fiber web obtained by splitting a two-component composite continuous single yarn composed of a polyethylene polymer and a polyethylene terephthalate polymer in advance by buckling. Since a fiber web was used, it was excellent in all of tensile strength, peel strength and flexibility.

In Example 4, a short fiber web was laminated on a long fiber web in which the fineness of a splitting filament made of a polyethylene polymer was smaller than that in Example 1 and split by splitting in advance by buckling treatment. Since it was a composite nonwoven fabric subjected to entanglement treatment using a liquid flow treatment device, it was excellent in all of tensile strength, delamination strength and flexibility.

In Example 5, a short-fiber web was laminated on a long-fiber web in which a two-component composite continuous single yarn consisting of a polyethylene polymer and a polyethylene terephthalate polymer had been split beforehand by liquid flow treatment. Since the composite nonwoven fabric was subjected to liquid flow low-pressure entanglement using an apparatus, it was excellent in all of tensile strength, delamination strength, and flexibility.

In Example 6, a short fiber web was laminated on a long fiber web composed of a two-component composite continuous single yarn composed of a polyethylene polymer and a polyethylene terephthalate polymer.
Since the composite nonwoven fabric was subjected to splitting and entanglement at the same time using a liquid flow treatment device, it was slightly superior in delamination strength, flexibility, and tensile strength.

On the other hand, the comparative example is a composite nonwoven fabric obtained by laminating a short fiber web on a long fiber web made of a single-phase continuous fiber of a polyethylene terephthalate polymer and performing an entanglement treatment using a liquid flow treatment device. The peel strength was extremely poor.

Example 7 Example 1 was the same as Example 1 except that the liquid flow pressure was set to 30 kg / cm ² G by the high-pressure liquid flow treatment device.
Under the same conditions as above, a composite nonwoven fabric having a basis weight of 50 g / m ² was obtained. The physical properties of the obtained composite non-woven fabric were 18 kg / tensile strength.
The width was 5 cm, the compression hardness was 8 g, and the peel strength was 410 g.

The long fiber web in which the group of ultrafine split filaments is developed in advance by the buckling treatment has a high degree of freedom of the filament and a large gap between the filaments because the group of ultrafine split filaments is in an unentangled state. In addition, the constituent fibers of the short fiber web easily enter and become entangled. Therefore, although the water pressure of the high-pressure liquid flow treatment in the lamination integration was set to a low water pressure, the obtained composite nonwoven fabric of Example 7 was excellent in delamination strength and particularly excellent in flexibility.

[0103]

The composite nonwoven fabric of the present invention is obtained by laminating a long fiber web composed of a two-component split type composite continuous fiber and a short fiber web composed of a two-component parallel type or eccentric core-sheath composite short fiber, Both webs are densely entangled and integrated using a flow treatment device, and further, a heat treatment of the laminate is a composite nonwoven fabric that expresses crimp of the short fiber web layer, and has high mechanical properties and peel strength, It has excellent flexibility and good filter performance, and is suitable for medical and hygiene materials, clothing, living related materials, and industrial materials.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing one embodiment of a cross section of a two-component composite continuous single yarn used in the present invention.

FIG. 2 is a schematic diagram of one embodiment of a cross section of a two-component composite continuous single yarn used in the present invention.

FIG. 3 is a schematic diagram showing one embodiment of a cross section of a two-component composite continuous single yarn used in the present invention.

FIG. 4 is a schematic diagram of one embodiment of a cross section of a two-component composite continuous single yarn used in the present invention.

FIG. 5 is a schematic diagram of one embodiment of a cross section of a parallel type bicomponent conjugate short fiber used in the present invention.

FIG. 6 is a schematic diagram showing one embodiment of a cross section of a parallel type bicomponent conjugate short fiber used in the present invention.

FIG. 7 is a schematic cross-sectional view of an eccentric core-sheath type bicomponent conjugate short fiber used in the present invention.

FIG. 8 is a schematic cross-sectional view of an eccentric core-sheath type bicomponent conjugate short fiber used in the present invention.

Claims (10)

[Claims] 1. A fiber-forming low-melting polymer and a fiber-forming high-melting polymer incompatible with the low-melting polymer and having a melting point 30 to 180 ° C. higher than the melting point of the low-melting polymer. A long-fiber web composed of a group of ultrafine splitting filaments composed of the low-melting polymer and the high-melting polymer expressed by dividing a split-type two-component composite continuous single yarn, and short fibers mainly composed of the following short fibers The web is laminated, and the constituent fibers of the long fiber web, the constituent fibers of the long fiber web and the short fiber web, and the constituent fibers of the short fiber web are integrated by three-dimensional confounding. Composite nonwoven. Short fibers: short fibers made of a fiber-forming polymer and having latent crimping ability. 2. The short-fiber web according to claim 1, wherein the short-fiber web is mainly composed of a fiber-forming polymer, has short crimping ability, and is composed of short fibers in which the latent crimp is manifested. Composite nonwoven. 3. The short fiber having latent crimping power constituting the short fiber web is mainly one of the following short fibers. Composite nonwoven fabric. Short fiber: a parallel type bicomponent conjugate short fiber in which two types of fiber-forming polymers having mutually different heat shrinkages are arranged in parallel along the length direction of the fiber, and the two types of fiber-forming weight. An eccentric core-sheath type bicomponent conjugate short fiber composed of a united core and an eccentric core portion. 4. A staple fiber web comprising natural fibers and / or
The composite nonwoven fabric according to any one of claims 1 to 3, wherein a short fiber made of a regenerated fiber is mixed with less than 30% by weight. 5. A fiber-forming low-melting polymer and a fiber-forming high-melting polymer incompatible with the low-melting polymer and having a melting point 30 to 180 ° C. higher than the melting point of the low-melting polymer. The split type two-component composite continuous single yarn group is melt-spun, and the composite continuous single yarn group is taken up using air soccer, spread and deposited on a movable collecting surface such as a screen conveyor to form a long fiber web, The long fiber web is subjected to a partial thermocompression treatment on the composite continuous single yarn group using a partial thermocompression bonding apparatus to obtain a long fiber web, and at least one surface of the long fiber web is mainly made of a fiber-forming polymer, A short fiber web made of short fibers having latent crimping ability is laminated, and then the laminate is subjected to a high-pressure liquid flow treatment, so that the constituent fibers of the long fiber web, the long fiber web and the short fiber web are combined. Constituent fibers The three-dimensionally entangled constituent fibers of the short fiber web integrate the laminate to obtain a composite nonwoven fabric, which has the lowest melting point among the fiber-forming polymers forming the constituent fibers of the composite nonwoven fabric. A method for producing a composite nonwoven fabric, wherein heat treatment is performed at a temperature lower than the melting point of a polymer to make latent crimp of short fibers apparent. 6. A fiber-forming low-melting polymer and a fiber-forming high-melting polymer which is incompatible with the low-melting polymer and has a melting point 30 to 180 ° C. higher than the melting point of the low-melting polymer. The split type two-component composite continuous single yarn group is melt-spun, and the composite continuous single yarn group is taken up using air soccer, spread and deposited on a movable collecting surface such as a screen conveyor to form a long fiber web, The long continuous web is subjected to a partial thermocompression treatment on the composite continuous single yarn group using a partial thermocompression bonding apparatus to obtain a long fiber web, and a short fiber web mainly comprising the following short fibers on at least one surface of the long fiber web. Then, the laminate is subjected to a high-pressure liquid flow treatment, and the constituent fibers of the long fiber web, the constituent fibers of the long fiber web and the short fiber web, and the constituent fibers of the short fiber web are three-dimensionally. Confounding A method for producing a composite nonwoven fabric, wherein the laminate is integrated. Short fibers: short fibers made of a fiber-forming polymer, having latent crimping ability, and having the latent crimps manifested. 7. A low-melting polymer obtained by splitting and splitting the composite continuous single yarn present in a portion of the long fiber web which has not been thermocompression-bonded by buckling treatment as a long fiber web. Alternatively, at least a part of a group of ultrafine splitting filaments composed of a high melting polymer is expressed, and the group of ultrafine splitting filaments uses a long fiber web in an unentangled state. 3. The method for producing a composite nonwoven fabric according to claim 1. 8. The composite continuous single yarn present in a portion that is not thermocompression-bonded by applying a high-pressure liquid flow to a partially thermocompression-bonded long fiber web as a long fiber web, thereby obtaining a low melting point weight. Ultra-fine splitting filament group composed of coalesced or high melting point polymer at least partially expressed,
The method for producing a composite nonwoven fabric according to any one of claims 5 and 6, wherein a long fiber web in which ultrafine split filament groups are three-dimensionally entangled is used. 9. The composite according to claim 5, wherein the short fibers having latent crimping power constituting the short fiber web are mainly one of the following short fibers. Manufacturing method of nonwoven fabric. Short fiber: a parallel type bicomponent conjugate short fiber in which two types of fiber-forming polymers having mutually different heat shrinkages are arranged in parallel along the length direction of the fiber, and the two types of fiber-forming weight. An eccentric core-sheath type bicomponent conjugate short fiber composed of a united core and an eccentric core portion. 10. The production of a composite nonwoven fabric according to any one of claims 5 to 9, wherein the short fiber web is blended with less than 30% by weight of short fibers composed of natural fibers and / or regenerated fibers. Method.