JPH10273864A - Composite nonwoven fabric and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a composite nonwoven fabric having high interlaminar peeling strength, flexibility and filtering performance by preparing a filament web consisting of an ultrafine splittable filament group composed of a high-melting polymer and a low-melting polymer and a stable fiber web composed of core-sheath conjugate staple fiber and integrating the webs by three-dimensional interlocking treatment. SOLUTION: The objective nonwoven fabric is produced by laminating a filament web consisting of an ultrafine split filament group composed of a fiber-forming low- melting polymer A and a fiber-forming high-melting polymer B incompatible with the polymer A and having a melting point higher than that of the polymer A by 30-180 deg.C and obtained by splitting a splittable bicomponent conjugate filament composed of the polymers A and B to a staple fiber web consisting of a core-sheath conjugate staple fiber having a fiber-forming low-melting polymer C as the sheath part and a fiber-forming high-melting polymer D as the core part and integrating the filament web to the staple fiber web by the three-dimensional interlocking of the constituent fibers of the filament web with each other, the constituent fiber of the filament web to that of the stable fiber web and the constituent fibers of the staple fiber web with each other.

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 composite nonwoven fabric in which a woven or knitted fabric is used as a base fabric and a nonwoven web made of split type bicomponent conjugate short fibers or an ultrafine fiber web obtained by a melt blown method is laminated thereon. 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, this laminated nonwoven structure is excellent in water absorption because natural fibers are laminated, but as is apparent from the object of improving the air permeability, it is apparent from the filter.
It has no performance. 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 technique, 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 nonwoven fabric in which a nonwoven fabric layer composed of an ultrafine split filament group composed of fiber-forming polymers and a short-fiber nonwoven fabric layer mainly composed of a fiber-forming polymer are laminated. An object of the present invention is to provide a composite nonwoven fabric having high delamination strength, excellent flexibility, and good filter characteristics, and a method for efficiently producing 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 point polymer A and the fiber forming high melting point polymer B which are incompatible with the low melting point polymer A and have a melting point 30 to 180 ° C. higher than the melting point of the low melting point polymer A And a long-fiber web consisting of a group of ultrafine splitting filaments composed of the low-melting polymer A and the high-melting polymer B, which are developed by splitting a split-type bicomponent composite continuous single yarn consisting of A short fiber web composed of a core-sheath composite short fiber in which a low-melting polymer C is disposed in a sheath portion and a fiber-forming high-melting polymer D is disposed in a core portion is laminated, and constituent fibers of a long fiber web, A composite nonwoven fabric characterized by being integrated by three-dimensional confounding between constituent fibers of a long fiber web and a short fiber web and between constituent fibers of a short fiber web.

The fiber-forming low melting point polymer A and the fiber forming high melting point polymer B which are incompatible with the low melting point polymer A and have a melting point 30 to 180 ° C. higher than the melting point of the low melting point polymer A The composite continuous single yarn group consisting of the following is melt-spun, and the composite continuous single yarn group is taken up using air soccer and spread and deposited on a movable collecting surface such as a screen conveyor to obtain a long fiber web. And performing 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 composed of a fiber-forming low melting point weight. Coalescing C
A short fiber web composed of a core-sheath composite short fiber in which a fiber-forming high-melting polymer D is disposed in a core portion in a sheath portion is laminated, and then the laminate is subjected to a high-pressure liquid flow treatment to obtain a long fiber web. Manufacture of a composite nonwoven fabric characterized by integrating a laminated body as a whole by three-dimensionally entanglement of constituent fibers, constituent fibers of a long fiber web and a short fiber web, and constituent fibers of a short fiber web. Method.

In the method for producing a composite non-woven fabric, the continuous filament yarn which has been partially thermocompressed is split by splitting the composite continuous single yarn present in a portion which has not been thermocompression-bonded by buckling. The ultrafine splitting filament group composed of the low melting point polymer A or the high melting point polymer B is expressed at least in part, and the ultrafine splitting filament group is characterized by using a long fiber web in an unentangled state. Of producing a composite nonwoven fabric.

[0008] In the method for producing a composite nonwoven fabric, as the long fiber web, a high-pressure liquid flow treatment is applied to a partially thermocompressed long fiber web to divide the composite continuous single yarn existing in a portion not thermocompressed. Using a long fiber web in which at least a part of the ultrafine splitting filament group composed of the low melting point polymer A or the high melting point polymer B is expressed, and the ultrafine splitting filament groups are three-dimensionally entangled with each other. A method for producing a composite nonwoven fabric, comprising:

[0009]

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 is a fiber-forming low-melting polymer A
And a fiber-forming high-melting polymer B incompatible with the low-melting polymer A. The reason why the low melting point polymer A and the high melting point polymer B 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 B 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 A. 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 A and the fiber-forming high-melting polymer B are both exposed on the surface of the fiber, and one component is divided by the other component in the cross section of the fiber. It is divided into splittable shapes.

The 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 A and the high-melting polymer B by the split splitting process, and the split filament made of the low-melting polymer A is used. Alternatively, at least a part of the split filament composed of the high melting point polymer B is developed. 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, more preferably 0.1 to 0.5 denier. 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 A and the high melting point polymer B constituting the split type two-component composite continuous single yarn include polyolefin / polyamide, polyolefin / polyester, polyamide / polyester and the like. However, these are representative examples, and other various combinations are also 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 polymer includes a matting agent, a pigment, a flame retardant, a deodorant, an antistatic agent, an antioxidant, and an ultraviolet absorber as long as the object of the present invention can be achieved. Any additive such as 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 processed using a partial thermocompression bonding apparatus and partially thermocompression bonded. Partial thermocompression bonding means, for example, 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 A and having an engraved pattern engraved on the surface, and a heated metal roll having a smooth surface. It means that the long fiber webs that come into contact with the engraved pattern are thermally pressed by using a so-called hot embossing roll or by using an ultrasonic welding machine by passing a long fiber web therebetween.

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 temperature (embossing roll temperature) in the thermocompression treatment is a temperature lower than the melting point of the fiber-forming low melting point polymer A, preferably 5 to 30 ° C. lower than the melting point of the fiber forming low melting point polymer A. And 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 point polymer A, the thermocompression bonding becomes strong, so that the dimensional stability of the long fiber web is excellent, and in the high pressure liquid flow treatment to be performed later. At the time of split splitting and entanglement integration of the composite continuous single yarn, the partial thermocompression bonding portion remains, and the ultrafine splitting filament group existing in the non-thermocompression bonding portion is three-dimensionally entangled. Therefore, the obtained composite nonwoven fabric has 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 A, the partial thermocompression bonding section is in a state of temporary thermocompression bonding in which the fiber form is left. At the time of split splitting and interlacing integration of continuous single yarn, the partial thermocompression bonding part is peeled off and becomes fibrous, and the composite continuous single yarn group and ultrafine split filament group can move freely, more randomly Confound three-dimensionally. 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.

[0025] As a method for splitting the two components forming a single yarn in advance into a long fiber web which 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-in type crimper through a buckling machine, that is, a pair of rolls, and divided 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 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 with the short fiber web, entanglement and integration of the constituent fibers can be performed with the energy of the low-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 processing in advance in accordance with the specification of the high-pressure liquid flow energy in the subsequent lamination integrated entanglement processing 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 a non-entangled state. Since the degree of freedom of the filament is large and the gap between the filaments is large, the constituent fibers of the short fiber web are not restricted between the group of ultrafine split filaments in the subsequent lamination integrated entanglement with the short fiber web. Easy to get in and entangle. 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.

A long fiber web in which a group of ultrafine splitting filaments is developed in advance by a method of splitting splitting by applying a high-pressure liquid flow and giving an impact is obtained by splitting almost all split-type bicomponent composite continuous single yarns. 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 treatment with the short fiber web, the action of splitting and splitting 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.

The short fiber web used in the present invention is mainly constituted by a core-sheath composite short fiber made of a fiber-forming polymer such as polyolefin, polyamide and polyester. This core-sheath composite short fiber is a fiber-forming low melting polymer C
In the sheath portion, the fiber-forming high melting point polymer D is disposed in the core portion, the difference between the melting point of the polymer disposed in the core portion and the melting point of the polymer disposed in the sheath portion is , 20 ° C. or higher. The difference in melting point between the core and the sheath polymer is 20 ° C
If it is less than 1, when the obtained composite nonwoven fabric is subjected to heat treatment in accordance with the required performance, when treated at a high temperature, the polymer in the sheath portion of the fiber surface softens or melts, and the polymer in the core portion thermally degrades. Therefore, the tensile strength, tear strength and bending strength of the fiber itself tend to decrease. On the other hand, when the polymer is treated at a low temperature, the polymer in the core does not thermally deteriorate, but the polymer in the sheath does not sufficiently soften or melt, so that it is difficult to expect the effect of the heat treatment. Therefore, assuming that the difference in melting point between the core and the sheath polymer is at least 20 ° C., the heat treatment causes the sheath polymer to be at least partially softened or melted at the fiber intersection and fused and bonded. The strength of the nonwoven fabric can be maintained because the core component polymer maintains the fiber structure without thermal degradation. Therefore, since the short fiber used in the present invention has the above-described configuration, the effect of heat-treating the composite nonwoven fabric can be expected.

For example, in order to suppress fluffing of the surface of the composite nonwoven fabric, the sheath is heat-treated at a temperature lower than the melting point of the polymer of the core constituting the short fibers to a temperature higher than the melting point of the polymer of the sheath. Part of the polymer is at least partially softened or melted at the fiber intersection, thereby suppressing fluffing of the surface of the composite nonwoven fabric. On the other hand, since the fiber structure is maintained without thermally degrading the polymer of the core, it is possible to obtain a composite nonwoven fabric having excellent mechanical strength while maintaining the flexibility of the composite nonwoven fabric.

When a heat treatment such as heat sealing is applied to the composite nonwoven fabric for the purpose of producing a product such as a bag or a simple mask using the composite nonwoven fabric, the melting point of the polymer of the sheath portion constituting the short fiber is not higher than the melting point. Heat treatment at a temperature to cause the sheaths of the short fibers or the sheath of the short fibers and the low melting point polymer constituting the long fiber web to be firmly fused by hot melting, while the weight of the core of the short fibers is increased. Keep the fiber structure without thermal degradation of the coalescence,
It is possible to obtain a product made of a composite nonwoven fabric having excellent mechanical strength at the heat seal portion.

Even when the heat-sealed portion of the composite nonwoven fabric is cut by die-cutting or the like, the cut portion has a fiber structure without thermally deteriorating the polymer of the core portion of the short fiber, so that it is flexible. However, since the constituent fibers are firmly fused by thermal fusion, the quality is also maintained.

Further, when high filter performance is required for the composite nonwoven fabric, the calendering is performed at a temperature not higher than the melting point of the polymer of the sheath portion constituting the short fiber, so that the sheath portions of the short fiber or the short fiber can be separated. The sheath portion of the short fiber and the low melting point polymer constituting the long fiber web are at least partially thermocompression-bonded to reduce the gap between the constituent fibers of the composite nonwoven fabric,
A composite nonwoven fabric having excellent filter performance can be obtained. It is possible to control the filter performance according to the required filter performance, that is, by appropriately selecting the processing temperature and the processing linear pressure applied to the heat calendering in order to achieve the desired gap between the constituent fibers. It is. In addition to filters, depending on the required performance,
In some cases, the heat calendering may be performed at a temperature lower than the melting point of the core polymer constituting the short fiber to a temperature higher than the melting point of the sheath polymer and at a high linear pressure.

Examples of fiber-forming polymers such as polyolefin, polyamide and polyester which can be used for the core-sheath conjugate short fibers are the same as the fiber-forming polymers used for the split type two-component composite continuous single yarn. I just need. As the combination of the core / sheath polymer, a polyester polymer / polyolefin polymer, a high melting polyester polymer /
Low melting point polyester polymer, polyamide polymer / polyolefin polymer, polyester polymer / polyamide polymer, high melting point polyamide polymer / low melting point polyamide polymer, high melting point polyolefin polymer / low melting point Polyolefin polymers and the like can be mentioned.

Of these combinations, the core polymer is a polyethylene terephthalate-based polymer in terms of the mechanical properties and productivity of the composite nonwoven fabric, and the sheath polymer is a heat-sealable and thread-forming material. Core-sheath composite short fibers using a polyethylene polymer or a polypropylene polymer are more preferred.

The composite ratio (weight ratio) of the polymer of the core and the sheath of the core-sheath composite short fiber can be arbitrarily determined, but is 75/25 to 25 in view of the strength of the fiber itself and the thermal adhesiveness between the fibers. The range of / 75 is preferred.

The core-sheath conjugate short fibers used in the present invention are generally produced by the following method. The fiber-forming low-melting polymer C is sheathed and the fiber-forming high-melting polymer D is spun from a spinneret which is positioned at the core, and the air is blown using a conventionally known cooling device such as horizontal spraying or annular spraying. And apply the finishing oil, and then, as a rule, are wound up as undrawn yarn via a take-up roll. Pickup speed is 500m /
Min to 2000 m / min apply. Next, a plurality of the obtained undrawn yarns are drawn and aligned to form a tow, and after performing drawing using a known drawing machine, crimping is applied by a press-in type crimping device and cut into a predetermined fiber length. To obtain short fibers. The stretch tow may be heat-set at a temperature equal to or lower than the melting point of the material depending on the required use.

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, a modified cross section, a multi-leaf cross section, or the like, depending on the required performance.

The short fiber web may be made of natural fibers such as cotton, wool, linen, silk and / or regenerated short fibers such as rayon, depending on the required properties such as imparting water absorption or imparting high gloss. 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 bicomponent which forms the single yarn in advance is divided into extra fine 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 may be a laminate obtained by 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 this 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. .

The porous support member for supporting the laminate used in performing the high-pressure liquid flow treatment includes, 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 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, so that the front and back surfaces of the composite nonwoven fabric are densely entangled and 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 circulating dryer. A composite nonwoven can be obtained.

As described in detail above, 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 closely 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 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, and moisture and the like are included in the composite nonwoven fabric by capillary action.

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 closely 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 of the composite nonwoven fabric having large inter-fiber voids, and then fine particles and fine dust which cannot be completely filtered are removed on the short fiber web side. Can be removed on the long fiber web side having a small inter-fiber void. Therefore, since the composite nonwoven fabric of the present invention is a single nonwoven fabric, it is possible to separate and collect according to the size of the object to be filtered, and as a filter cloth with a long filter life that can maintain excellent filter performance over a long period of time. Can be used. In addition, by appropriately selecting the linear pressure, the heat treatment temperature, and the like on the short fiber web side and performing calendering, it is possible to adjust the interfiber space of the short fiber web and remove medium particles and dust.

[0060]

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./minute 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) Relative viscosity of nylon 6 (b): 96
% Sulfuric acid was used as a solvent, and 1 g of a sample was dissolved in 100 cc of the solvent.

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

(5) 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.

(6) 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.

(7) 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.

(8) Water absorption (mm / 10 minutes) of nonwoven fabric:
The measurement was performed according to the Bilek method described in JIS L 1096.

Example 1 As a fiber-forming low melting point polymer A, the melting point was 130 ° C.
Using a polyethylene polymer having a melt index value of 25 g / 10 minutes as measured by the method of STM-D-1238 (E), as a fiber-forming high melting point polymer B, a melting point of 258 ° C. and a relative viscosity ( A) used a polyethylene terephthalate polymer of 1.38. 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, 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 2.4 denier.

The obtained long fiber web was subjected to splitting treatment of a polyethylene polymer and a polyethylene terephthalate polymer by using a buckling machine (Microcreper, manufactured by Microtex Co., Ltd.). When the long fiber web after split processing was observed with a microscope, the ultrafine split filament made of polyethylene polymer and the ultrafine split filament made of polyethylene terephthalate polymer were each in an unentangled state, and the splitting rate was 92%. Met. The fineness of the ultrafine split filament made of polyethylene polymer was 1.2 denier, and the fineness of the ultrafine split filament made of polyethylene terephthalate polymer was 0.2 denier.

On the other hand, as a short fiber web, a core-sheath composite type in which a polyethylene polymer was positioned at the sheath as the fiber-forming low-melting polymer C and a polyethylene terephthalate polymer was positioned at the core as the fiber-forming high-melting polymer D was used. Short fibers were prepared.

That is, using the same polyethylene polymer and polyethylene terephthalate polymer as used in the production of the split type two-component composite continuous single yarn, the polyethylene polymer was used as the sheath and the polyethylene terephthalate polymer was used as the core. The composite ratio was set to 1: 1 by weight from the core-sheath composite type spinneret placed at the same position, and extruded at a single hole discharge rate of 0.80 g / min. After cooling the spun yarn and applying the finishing oil, the take-up speed is 1000 m / min through a take-off roll,
It was wound up as an undrawn yarn. Subsequently, a plurality of the obtained undrawn yarns are drawn and aligned to form a tow. After drawing is performed at a draw ratio of 2.6 using a known drawing machine, crimping is performed by a press-in type crimping device. And cut to a fiber length of 51 mm.
Denier staple fibers were obtained. Using the short fibers, a short fiber web having a basis weight of 20 g / m ² was obtained using a random card machine.

Next, the short fiber web was laminated on one side of the long fiber web which had been subjected to the split splitting treatment 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 .

Example 2 In Example 1, except that the following short fiber web was used,
A composite nonwoven fabric of Example 2 was obtained in the same manner as in Example 1. That is, as the fiber-forming low-melting polymer C, the same polyethylene polymer as in Example 1 was used in the sheath portion, and as the fiber-forming thermoplastic polymer D, the melting point was 160 ° C. and ASTM-D-12.
The melt ratio obtained by the method of Example 38 (L) was 30 g / 10 min, and the composite ratio was set to 1: 1 by weight from a core-sheath composite spinneret in which a polypropylene polymer was disposed in the core. Extrusion was performed at a hole discharge rate of 1.04 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, and after drawing at a draw ratio of 3.4 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 3 denier. Using the short fibers, a short fiber web having a basis weight of 20 g / m ² was prepared by a random card machine.

Example 3 80% by weight of a core-sheath composite short fiber composed of the same polyethylene polymer and polyethylene terephthalate polymer as in Example 1, cotton having an average single fiber fineness of 1.5 denier and an average fiber length of 25 mm A fiber weight of 5 g was obtained under the same conditions as in Example 1 except that a short fiber web having a basis weight of 20 g / m ² was produced by blending 20% by weight of fibers with a random card machine.
A composite nonwoven fabric of 0 g / m ² was obtained.

Example 4 The same polyethylene polymer and polyethylene terephthalate polymer as in Example 1 were used, and a composite spinneret having a yarn cross section as shown in FIG. 2 and a total division number of 12 was used.
The composite ratio of the polyethylene polymer and the polyethylene terephthalate polymer was set to 1: 1 by weight, and the single hole discharge amount was 1.1.
Extruded at 2 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, Partial thermocompression bonding was performed on the long fiber web using a hot embossing roller under the conditions of a point pattern, a processing temperature of 120 ° C., and a press contact area ratio of 10%.
g / m ² long fiber web was obtained. The fineness of the split type bicomponent conjugate continuous fibers collected from the fiber assembly was about 2.4 denier. Next, the long fiber web was subjected to splitting treatment of a polyethylene polymer and a polyethylene terephthalate polymer using a buckling machine (Microcreper, manufactured by Microtex Co., Ltd.). 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 85%. there were. The fineness of the ultrafine splitting filament made of a polyethylene polymer and the ultrafine splitting filament made of a polyethylene terephthalate polymer were 0.2 denier, respectively.

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 and high-pressure liquid flow treatment conditions.

Example 5 The same long-fiber web as in Example 1 was split into a polyethylene polymer and a polyethylene terephthalate polymer by high-pressure liquid flow treatment. That is, a long-fiber web was loaded on a 100-mesh wire net, and a high-pressure liquid flow treatment device in which injection holes having a hole diameter of 0.12 were arranged with a hole area of 0.62 mm was used. The treatment was performed under the conditions of a liquid flow pressure of 50 kg / cm ² G. 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 2 for the short fiber web and high-pressure liquid flow treatment.

Example 6 In Example 1, the same short fiber web as in Example 1 was applied to one surface of the long fiber web which had been subjected to the partial thermocompression treatment obtained in Example 1 and had not been subjected to the split fiber treatment. Except for laminating, a composite nonwoven fabric having a basis weight of 50 g / m ² was obtained in the same manner as in Example 1. When the composite nonwoven fabric after splitting was observed with a microscope, the splitting rate was 72%.

Example 7 In a long fiber web, a nylon 6 polymer having a melting point of 225 ° C. and a relative viscosity of 2.6 was used as the fiber-forming low melting point polymer A, and a fiber forming high melting point polymer B was used. The same polyethylene terephthalate polymer as in Example 1 was used. The composite ratio of the nylon 6 polymer and the polyethylene terephthalate polymer was determined by weight using a composite spinneret having a yarn cross section as shown in FIG. To 1: 1 and the single hole discharge amount =
Extruded at 1.28 g / min. After cooling the spun yarn,
It is drawn at a speed of 4800 m / min by air soccer, spread by a known spreader, collected and deposited on a moving collecting surface to form a long fiber web, and the long fiber web is heated by a hot emboss roller. Point pattern, processing temperature 185 ℃
Partial thermocompression bonding was performed under the condition of a pressed area ratio of 10% 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 is about 2.
It was 4 denier. Next, the long fiber web was subjected to a splitting treatment of a nylon 6 polymer and a polyethylene terephthalate polymer by a buckling machine (Microcreper, manufactured by Microtex Co., Ltd.). When the long fiber web after the splitting treatment was observed with a microscope, the ultrafine splitting filament made of nylon 6 polymer and the ultrafine splitting filament made of polyethylene terephthalate polymer were each in an unentangled state, and the splitting rate was 95%. Met. Also nylon 6
The fineness of the ultrafine split filament made of a polymer was 1.2 denier, and the fineness of the ultrafine split filament made of a polyethylene terephthalate polymer was 0.2 denier.

The high-pressure liquid flow processing conditions in the short fiber web and the lamination and entanglement integration processing were performed under the same conditions as in Example 1.
A composite nonwoven fabric having a basis weight of 50 g / m ² was obtained.

Comparative Example 1 The same polyethylene terephthalate polymer as in Example 1 was extruded at a single hole discharge rate of 1.33 g / min using a single-phase spinneret having a round yarn cross section. 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, Long fiber web with hot emboss roller, point pattern, processing temperature 240
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 single-phase continuous fiber was 2.4 denier. The short fiber web and the high-pressure liquid flow treatment conditions in the lamination and confounding integration treatment were performed under the same conditions as in Example 1 to obtain a composite nonwoven fabric having a basis weight of 50 g / m ² .

The physical properties of the composite nonwoven fabrics and nonwoven fabrics obtained in Examples 1 to 7 and Comparative Example 1 were measured and are shown in Table 1.

[0085]

[Table 1]

As is clear from Table 1, Examples 1 and 2
Is a two-component composite continuous single yarn consisting of a polyethylene polymer and a polyethylene terephthalate polymer. Since the composite nonwoven fabric was used, it was excellent in all of tensile strength, delamination strength, and flexibility.

In Example 3, a two-component composite continuous single yarn consisting of a polyethylene polymer and a polyethylene terephthalate polymer was split into pieces by a buckling treatment in advance to obtain a long fiber web. Since it is a composite nonwoven fabric obtained by laminating short fiber webs made of a blend of core-sheath composite short fibers and cotton and performing entanglement treatment using a liquid flow treatment device, it has tensile strength, delamination strength, and flexibility. It was excellent and could impart water absorption.

In the fourth embodiment, a short fiber web is laminated on a long fiber web in which the fineness of a splitting filament made of a polyethylene polymer is smaller than that in the first embodiment, which has been split and split in advance by a 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 composed of a polyethylene polymer and a polyethylene terephthalate polymer was 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 consisting of a two-component composite continuous single yarn consisting 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.

In Example 7, a short-fiber web was laminated on a long-fiber web obtained by splitting a two-component composite continuous single yarn comprising a nylon 6 polymer and a polyethylene terephthalate polymer in advance by buckling and splitting it. Since it was a composite nonwoven fabric subjected to splitting and entanglement treatment using a processing apparatus, it was slightly excellent in flexibility, excellent in delamination strength, and particularly excellent in tensile strength.

On the other hand, Comparative Example 1 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. , Peel strength was remarkably inferior.

Example 8 The composite nonwoven fabric obtained in Example 1 was subjected to calendering. That is, using a calendering device consisting of a metal roll at 110 ° C. and a cotton roll at room temperature,
The short fiber web side of the composite nonwoven fabric was passed as a metal roll and calendered under the condition of a linear pressure of 20 kg / cm to obtain a composite nonwoven fabric with a basis weight of 50 g / m ² . The physical properties of the obtained composite nonwoven fabric are shown in Table 1.

The calendered composite nonwoven fabric of Example 8 was obtained by heating the sheath portions of the core-sheath composite fibers, which are constituent fibers of the short fiber web, and the sheath portion and the low melting point polymer forming the long fiber web. After compression bonding, the delamination strength between the long fiber web and the short fiber web was strong, and the composite nonwoven fabric was firmly integrated. In addition, on the short fiber web side, the inter-fiber density is reduced by thermocompression bonding of the constituent fibers by heat treatment,
When this composite nonwoven fabric was used for a filter or the like, excellent performance was exhibited.

Example 9 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 19 kg / tensile strength.
It had a width of 5 cm, a compression stiffness of 14 g, and a peel strength of 360 g.

The long fiber web in which the group of ultra-fine splitting filaments is developed in advance by buckling treatment has a high degree of freedom of the filaments and a large gap between the filaments because the group of ultra-fine splitting 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 9 was excellent in peeling strength and particularly excellent in flexibility.

[0097]

The composite nonwoven fabric according to the present invention is obtained by laminating a long fiber web composed of a two-component split type composite continuous single yarn and a short fiber web composed of a two-component core-sheath composite continuous fiber, and a liquid flow treatment device. Is a composite nonwoven fabric in which both webs are densely entangled and integrated with each other. It has high mechanical properties and peel strength, has excellent flexibility, and has good filter performance.
It is suitable for sanitary 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.

Claims (8)

[Claims] 1. A fiber-forming low melting point polymer A and a fiber forming high melting point weight which are incompatible with the low melting point polymer A and have a melting point 30 to 180 ° C. higher than the melting point of the low melting point polymer A. A long-fiber web consisting of a group of ultrafine splitting filaments composed of the low-melting polymer A and the high-melting polymer B, which are developed by dividing the split type two-component composite continuous single yarn comprising the union B; Short fiber webs composed of short fibers are laminated and integrated by three-dimensional confounding of 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. A composite nonwoven fabric comprising: Short fiber: a core-sheath composite short fiber in which a fiber-forming low-melting polymer C is disposed in a sheath and a fiber-forming high-melting polymer D is disposed in a core. 2. In a short fiber web, natural fibers and / or
The composite nonwoven fabric according to claim 1, wherein a short fiber composed of regenerated fiber is mixed with less than 30% by weight. 3. The short-fiber web according to claim 1, wherein the polymer of the sheath of the core-sheath composite short fiber is at least partially softened or melted at the fiber intersection, and the fibers are heat-sealed to each other. The composite nonwoven fabric according to claim 1. 4. A fiber-forming low melting point polymer A and a fiber forming high melting point weight which is incompatible with said low melting point polymer A and has a melting point 30 to 180 ° C. higher than the melting point of said low melting point polymer A. The split type two-component composite continuous single yarn group composed of the combined B is melt-spun, the composite continuous single yarn group is taken up by using an air soccer, and is spread and deposited on a movable collecting surface such as a screen conveyor to obtain a long yarn. A 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 the following short fibers. The short fiber web is laminated, and then the high pressure liquid flow treatment is applied to the laminate, 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 separated. Three-dimensional A method for producing a composite nonwoven fabric, wherein a laminate is integrated as a whole by entanglement. Short fiber: a core-sheath composite short fiber in which a fiber-forming low-melting polymer C is disposed in a sheath and a fiber-forming high-melting polymer D is disposed in a core. 5. A low-melting polymer obtained by splitting and splitting the composite continuous single yarn present in a portion of a long fiber web which has not been thermocompression-bonded by a buckling treatment as a long fiber web. 5. A filament fiber web in which at least a part of the group of ultrafine split filaments composed of A or the high melting point polymer B is expressed, and the group of ultrafine split filaments is unentangled. A method for producing a composite nonwoven fabric. 6. A long-fiber web, which is subjected to a high-pressure liquid flow treatment on a partially thermo-compressed long-fiber web to split and split the composite continuous single yarn present at a portion that has not been thermo-compressed, thereby obtaining a low melting point. It is characterized by using a long fiber web in which at least a part of the ultrafine split filament group composed of the polymer A or the high melting point polymer B is expressed, and the ultrafine split filament groups are three-dimensionally entangled with each other. A method for producing a composite nonwoven fabric according to claim 4. 7. A short fiber web comprising natural fibers and / or
The method for producing a composite nonwoven fabric according to any one of claims 4 to 6, wherein a short fiber made of a regenerated fiber is mixed with less than 30% by weight. 8. The laminate according to claim 4, wherein the laminate is subjected to a high-pressure liquid flow treatment, and then heat-treated at a temperature at which the polymer of the sheath constituting the short fibers melts. A method for producing a composite nonwoven fabric.