JPH10158968A - Nonwoven fabric and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a nonwoven fabric excellent in mechanical characteristics and dimensional stbility and rich in abrasion resistance and water absorbability. SOLUTION: This nonwoven fabric comprises water-absorbable fibers and conjugated synthetic short fibers in a mutually blended and three-dimensionally interlaced state. The conjugated synthetic short fibers comprise two or more kinds of thermoplastic polymers different in their melting points from each other. The thermoplastic polymer having the lowest melt point among two or more kinds of the thermoplastic polymers is exposed to the surfaces of the conjugated synthetic short fibers. The nonwoven fabric is subjected to a partial thermal adhesion treatment to thermally fuse the three-dimensionally interlaced fibers to each other with the thermoplastic polymer having the lowest melting point.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a nonwoven fabric having excellent mechanical properties and dimensional stability, as well as excellent flexibility and water absorption, and a method for producing the same.

[0002]

2. Description of the Related Art As a kind of nonwoven fabric, a natural fiber such as cotton is mixed with a synthetic fiber, and then the fibers constituting the nonwoven fabric are integrated by three-dimensional confounding by the action of a high-pressure liquid flow. There is something. The nonwoven fabric in which the natural fibers and the synthetic fibers are mixed has appropriate strength, water absorption and flexibility, and can be used for various applications.

[0003] However, although the nonwoven fabric subjected to the action of the high-pressure liquid flow has the appropriate strength as described above due to the intermingling of the individual fibers, compared with a nonwoven fabric or the like integrated by heat fusion, Its nonwoven strength is still quite low,
There is a problem that fluff is easily formed and abrasion resistance is poor.

[0004]

SUMMARY OF THE INVENTION The present invention solves the above problems and provides a nonwoven fabric which is excellent in mechanical properties and dimensional stability, and is also excellent in abrasion resistance and water absorption.

[0005]

SUMMARY OF THE INVENTION The present invention has the following features to solve the above-mentioned problems. (1) The fibers having water absorbency and the composite synthetic staple fiber are mixed to form a three-dimensional entanglement, and the composite synthetic staple fiber is composed of two or more thermoplastic polymers having different melting points. The thermoplastic polymer having the lowest melting point among the thermoplastic polymers of at least one kind is exposed on the surface of the composite synthetic staple fiber, and the fibers having the three-dimensional entanglement are heated by the thermoplastic polymer having the lowest melting point. A nonwoven fabric having a partially heat-sealed portion that is fused.

(2) A composite synthetic short fiber composed of two or more thermoplastic polymers having different melting points, wherein the thermoplastic polymer having the lowest melting point among the two or more thermoplastic polymers is exposed to the fiber surface. A non-woven web is formed by mixing and opening fibers having water absorbency to form a non-woven web, and then a high-pressure liquid flow treatment is applied to the non-woven web to form three-dimensional entanglement between the constituent fibers. The melting point of the thermoplastic polymer having the lowest melting point constituting the composite synthetic short fiber is (Tm)
A method for producing a nonwoven fabric, comprising performing a partial thermal bonding treatment at a temperature of (Tm-30) ° C to (Tm-5) ° C when the temperature is set to 0 ° C.

That is, according to the present invention, two different melting points are used.
The thermoplastic polymer having the lowest melting point (hereinafter referred to as “low melting point polymer”) among the thermoplastic polymers of at least one kind is exposed on the surface of the composite synthetic short fiber, and the thermoplastic polymer has a low melting point due to a partial heat bonding treatment. Because the melting point polymer is heat-fused, that is, in addition to the three-dimensional confounding of the fibers, the low-melting point polymer of the composite synthetic short fiber is partially thermally bonded, so that a strong nonwoven fabric is constructed, It has excellent dimensional stability, and has a three-dimensional entangled part remaining in the other part of the heat-bonded part for enhanced strength, so it is highly flexible and absorbs natural fibers and recycled fibers. Therefore, a nonwoven fabric rich in water absorbability can be obtained because of containing fibers having the following properties.

Further, in the present invention, since a partial thermal bonding process is performed in addition to the three-dimensional entanglement process, in the non-partial thermal bonding portion, the fibers are entangled and held down by the three-dimensional entanglement process. Therefore, fluffing is prevented and abrasion resistance is improved, and the abrasion resistance is improved even in a partially heat-bonded portion.

Therefore, according to the present invention, it is possible to obtain a nonwoven fabric which can be effectively used in various applications.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION The nonwoven fabric of the present invention has a three-dimensional entanglement in a state in which a fiber having a water absorbing property and a composite synthetic short fiber are mixed. Since the low melting point polymer on the surface of the fiber is heat-sealed, it has excellent mechanical properties, abrasion resistance, and dimensional stability, and also has excellent flexibility and water absorption.

Examples of the water-absorbing fiber include natural fibers such as cotton, ramie, wool, and silk cut into short fibers, viscose rayon, cuprammonium rayon, and Lyocell (registered trademark) which is a solvent-spun rayon. Recycled fibers are preferred. These fibers have the required water absorbency, and the nonwoven fabric of the present invention containing the fibers having the water absorbency together with the composite synthetic short fiber also exhibits water absorbency, and is used for industrial materials, clothing, sanitary materials, medical equipment, and the like. In the field of application materials, it is particularly suitable as a nonwoven fabric that requires water absorption.

In particular, when the above-mentioned cotton is used, bleached cotton or cotton wool can also be used. Here, the anti-hair is obtained from a woven or knitted fabric, thread, or fabric made of cotton, and the material of the anti-hair obtained from cotton is a woven or knitted fabric or fabric made of bleached cotton, or dyed. -It may be printed. Examples of the anti-hair machine that can effectively obtain the anti-hair include a rag machine, a knot breaker, a garnet machine, a turning machine, and the like.
The type and combination of anti-hair machines used depends on the shape of the fabric to be anti-haired, the thickness and twist strength of the constituent yarns, etc. It is effective to use a combination of the above-mentioned anti-hair machines. At this time, it is preferable that the opening ratio by the anti-hair device represented by the following formula is in the range of 30 to 95%.

[0013] Spreading rate (%) = (weight of unhaired fiber-weight of unspread fiber) x 100 / weight of unhaired fiber If the spreading rate is less than 30%, unspread fibers are present in the card web and the surface of the nonwoven fabric is not Not only does roughness occur, but the high-pressure liquid flow during the entanglement process does not sufficiently penetrate the web, and the entanglement between the constituent fibers of the nonwoven web becomes insufficient,
The strength of the nonwoven fabric tends to decrease. Conversely, if the opening ratio exceeds 95%, sufficient surface friction strength of the nonwoven fabric cannot be obtained.

The thermoplastic polymer constituting the composite synthetic short fiber includes an ester polymer, an olefin polymer, an amide polymer, an acrylic polymer,
Examples include a vinyl alcohol-based polymer, a copolymer containing these as a main component, or a blend composed of a combination of these polymers.

Examples of the ester polymer include aromatic dicarboxylic acids such as terephthalic acid, isophthalic acid and naphthalene-2,6-dicarboxylic acid, aliphatic dicarboxylic acids such as adipic acid and sebacic acid, and esters thereof. A homopolyester or a copolymer having a diol compound such as ethylene glycol, diethylene glycol, 1,4-butadiol, neopentyl glycol, cyclohexane-1,4-dimethanol as an alcohol component, and an alcohol component. Can be In addition, these ester polymers include paraoxybenzoic acid, 5-hydroxybenzoic acid,
Sodium sulfoisophthalic acid, polyalkylene glycol, pentaerythritol, bisphenol A or the like may be added or copolymerized.

[0016] The olefin polymer may have 2 to 2 carbon atoms.
18 aliphatic α-monoolefins such as ethylene, propylene, 1-butene, 1-pentene, 3-methyl-1
Polyolefin-based polymers comprising -butene, 1-hexene, 1-octene and 1-octadecene. These aliphatic α-monoolefins include, for example, butadiene, isopropylene, 1,3-pentadiene, styrene, α
An olefin polymer in which a similar ethylenically unsaturated monomer such as methylstyrene is copolymerized. In the case of an ethylene polymer, even if ethylene is copolymerized with propylene, 1-butene, 1-octene, 1-hexene, or a similar higher α-olefin by 10% by weight or less. In the case of a propylene-based polymer, ethylene or a similar higher α-olefin may be copolymerized with propylene at 10% by weight or less.

As the amide polymer, polyimino-1
-Oxotetramethylene (nylon 4), polytetramethylene adipamide (nylon 46), polycapramid (nylon 6), polyhexamethylene adipamide (nylon 66), polyundecanamide (nylon 11), polylaurolactamide (Nylon 12), polymetaxylene adipamide, polyparaxylylene decanamide, polybiscyclohexylmethanedecanamide, or an amide copolymer containing these monomers as a constitutional unit. In particular, polytetramethylene adipamide (nylon 4
In the case 6), tetramethylene adipamide obtained by copolymerizing polytetramethylene adipamide (nylon 46) with a polyamide component such as polycapramide, polyhexamethylene adipamide, polyundecamethylene terephthalamide or the like in an amount of 30 mol% or less. It may be a amide copolymer. However, in this case, if the copolymerization ratio of the polyamide component exceeds 30 mol%, the melting point of the copolymer decreases, and the mechanical properties of the nonwoven fabric are impaired.

The thermoplastic polymer used in the present invention includes a matting agent, a pigment, a flame retardant, a deodorant, an antistatic agent, an antioxidant, and an ultraviolet ray as long as the effects of the present invention are not impaired. Arbitrary additives such as an absorbent and an antibacterial agent may be added.

The composite synthetic staple fiber forming the nonwoven fabric is formed so that the low melting point polymer, that is, the thermoplastic polymer having the lowest melting point among the thermoplastic polymers constituting the composite synthetic staple fiber is exposed on the fiber surface. Must be As a result, the low-melting polymer present on the fiber surface upon partial heat bonding is softened or thermally melted, and this becomes an adhesive component to partially bond the nonwoven fabric.

As shown in FIG. 1, the cross section of the composite synthetic staple fiber is such that the low melting point polymer constituting the composite synthetic staple fiber is used as the sheath component 1 to constitute the composite synthetic staple fiber. The core component 2 is a thermoplastic polymer having the highest melting point among the thermoplastic polymers (hereinafter referred to as “high melting point polymer”).
A solid core-sheath type composite cross section disposed at the center of the fiber cross section is preferable. Alternatively, as shown in FIG. 2, a hollow core-sheath composite cross section having a hollow portion 3 inside the fiber cross section, that is, inside the core component 2 in the solid core-sheath composite cross section is preferable. When the low melting polymer is used as the sheath component 1, the core component 2 does not soften or heat melt when partially thermally bonded, and the composite synthetic staple fiber and thus the nonwoven fabric made of the composite synthetic staple fiber It is possible to maintain mechanical properties and flexibility.

When the fiber cross section has the above-mentioned core / sheath structure, specific examples of the combination include, for example, a core / sheath component of polyethylene / polypropylene, polyethylene / polyamide, polyethylene / polyester, polypropylene / polyester, polyamide / polyester, etc. There is something.

Further, in order not to cause softening and thermal melting of the core component of the composite synthetic short fiber, it is preferable that the temperature difference between the melting point of the high melting point polymer and the melting point of the low melting point polymer is 25 ° C. or more. . The melting point difference between the high melting polymer and the low melting polymer is 25
If the temperature is lower than ℃, the melting point differences are close to each other, so that applying partial heat bonding may cause softening and heat melting of the high melting point polymer, impairing the flexibility of the entire nonwoven fabric, and contacting the human body. In some applications, the feeling of softness is poor.

When the above-mentioned core-sheath type composite cross section is used as the fiber cross section of the composite synthetic short fiber, the ratio of the sheath component to the core component is determined by calculating the ratio of the sheath component to the core component = 25: 75 to 75:
It is preferably in the range of 25 (weight ratio). In particular, considering the flexibility of the nonwoven fabric, the ratio of the sheath component serving as the heat-sealing component is 50% by weight or less, that is, the sheath component: the core component = 3.
The ratio is preferably 5:65 to 50:50 (weight ratio).

In the nonwoven fabric of the present invention, the mixing ratio of the water-absorbing fiber and the composite synthetic staple fiber is (water-absorbing fiber) / (composite synthetic staple fiber) = 50/50 to 90/10.
(% By weight). By containing fibers having water absorbency in this way, the water absorbency of the entire nonwoven fabric is maintained. If the water-absorbing fiber content is less than 50% by weight, the resulting nonwoven fabric is poor in water absorption property, and the natural feeling of natural fibers or recycled fibers used as the water-absorbing fiber tends to be impaired. vice versa,
If the water-absorbing fiber content exceeds 90% by weight, the effect of partial heat bonding is hardly obtained due to a decrease in the amount of composite synthetic short fibers made of a thermoplastic polymer, and a nonwoven fabric having poor mechanical properties and dimensional stability tends to be obtained. For these reasons, the water-absorbing fiber content is more preferably 60 to 85% by weight. Therefore, the composite synthetic staple fiber composed of a thermoplastic polymer accounts for 50 to 10% by weight, more preferably 40% by weight.
The content is preferably up to 15% by weight.

Conversely, composite synthetic short fibers composed of two or more thermoplastic polymers having different melting points as described above are used.
By containing it by weight, a partial heat bonding effect can be sufficiently expected, and a nonwoven fabric having excellent mechanical properties and abrasion resistance can be obtained.

The single-filament fineness of the composite synthetic short fiber is preferably not less than 1.5 denier and less than 7 denier. If the single-fiber fineness is less than 1.5 denier, the spinnability of the composite synthetic short fiber tends to be reduced in the spinning process. Conversely, if the single-fiber fineness is 7 denier or more, the bulkiness of the nonwoven fabric can be obtained, but the entanglement of the composite synthetic short fiber is impaired and the nonwoven fabric is not only likely to have a low strength, but also the composite material constituting the nonwoven fabric. The amount of synthetic short fibers tends to decrease, and the effect of the partial heat bonding treatment tends to be difficult to obtain.

The nonwoven fabric of the present invention may be mixed with a synthetic short fiber different from the above-mentioned composite synthetic short fiber according to the intended use. Such a synthetic staple fiber must be capable of maintaining the fiber form without melting during heat treatment, that is, having a melting point equal to or higher than the high melting point polymer constituting the conjugate synthetic staple fiber of the present invention. . The mixing ratio of the synthetic short fibers to the entire nonwoven fabric is not particularly limited, but is preferably about 10 to 30% by weight in consideration of the water absorption and the adhesion between the fibers. When synthetic short fibers having a single yarn fineness of 1 to 3 denier are mixed at such a mixing ratio, mechanical properties and flexibility can be imparted to the nonwoven fabric. Further, when synthetic short fibers having a single yarn fineness of 5 to 15 denier are mixed, a nonwoven fabric having excellent bulkiness can be obtained. In addition, when a synthetic short fiber having a fiber cross section having an irregular cross section is mixed, the degree of entanglement during the three-dimensional entanglement process is improved, and the mechanical properties of the nonwoven fabric are improved. Such an effect is remarkable especially in a flat cross section among the modified cross sections, and becomes remarkable when the flatness, that is, the ratio of the major axis / minor axis is 5 or more.

The nonwoven fabric of the present invention is a nonwoven fabric in which the above-mentioned water-absorbing fiber and the conjugated synthetic short fiber are mixed in the above-mentioned ratio and three-dimensionally entangled between the constituent fibers. The three-dimensional entanglement referred to herein means that the constituent fibers are entangled not only in the vertical / horizontal direction of the nonwoven fabric but also in the thickness direction of the nonwoven fabric and have an integrated structure. This three-dimensional confounding is formed by a known so-called high-pressure liquid flow treatment, whereby the form of the non-woven fabric is maintained, and there is no fuzz due to abrasion, and a highly flexible non-woven fabric is obtained. You can do it.

The nonwoven fabric of the present invention is obtained by subjecting the nonwoven web subjected to the three-dimensional entanglement to a partial heat bonding treatment. Here, the partial heat bonding treatment may be performed to such an extent that the above-mentioned low-melting polymer constituting the composite synthetic short fiber is melted by heat and can function as an adhesive component. Therefore, a stronger thermal bond than that, for example, such a bond that the above-mentioned high melting point polymer is softened and thermally melted,
It is not preferable from the viewpoint of the flexibility of the obtained nonwoven fabric. In order to form such a partial heat bonding treatment, specifically, a heat embossing method using an embossing roll described later and a roll having a flat surface, or a partial method using an ultrasonic welding device. What is necessary is just to employ a heat bonding method etc.

According to the hot embossing method, bonding is performed by the low melting point component at the embossing point, and the three-dimensional entangled state of the fibers is maintained in other portions. The mechanical properties based on the presence of the bonded portion, the flexibility based on the presence of the three-dimensional entangled portion, and the anti-fuzziness, that is, the wear resistance, are both obtained. When an ultrasonic welding device is used, a nonwoven fabric having excellent flexibility can be obtained. In addition, the dimensional stability of the nonwoven fabric can be improved by performing the partial heat bonding treatment.

A nonwoven web subjected to three-dimensional entanglement retains a certain degree of mechanical properties as a nonwoven fabric by the action of a high-pressure liquid flow. The obtained nonwoven web is further partially subjected to thermal bonding to be integrated to obtain excellent nonwoven fabric strength. For example, a non-woven fabric obtained by subjecting a non-woven web having no three-dimensional entanglement to partial thermal bonding may be a non-woven fabric having extremely poor mechanical properties depending on the amount of composite synthetic staple fibers, or a fluff due to friction or washing. And the constituent fibers fall off, and the durability of the nonwoven fabric is poor. However, in the case of a non-woven fabric obtained by further partially applying heat bonding to a nonwoven web subjected to three-dimensional entanglement as in the present invention, the mechanical properties are improved in the partially heat-bonded portion and the fluff is formed. In the non-heat-bonded portion, the fibers are entangled and suppressed by the three-dimensional confounding treatment, so that fluff due to friction and washing can be prevented, and the wear resistance can be improved.

Further, in addition to such hot embossing, it is also possible to use a pattern roll to perform the treatment. In such a case, a free pattern such as a logo mark can be imparted to the nonwoven fabric.

Next, a method for producing a nonwoven fabric according to the present invention will be described. First, the water-absorbing fiber and the conjugate synthetic staple fiber are preferably combined with (a water-absorbing fiber) /
(Composite synthetic short fibers) = 50/50 to 90/10 (% by weight) are mixed and opened by carding using a card machine, for example, to prepare a nonwoven web. This non-woven web is a parallel web arranged in the traveling direction of the card machine according to the arrangement degree of the constituent fibers, a web in which the parallel web is cross-laid, a random web arranged randomly,
Alternatively, it may be any of semi-random webs arranged at an intermediate level, and may be appropriately selected depending on the application and the like. For example, when used for clothing, it is preferable to use a nonwoven web whose strength ratio in the length / width direction is approximately 1/1 in terms of strength as a nonwoven fabric.

The basis weight of the nonwoven web is 30 to 150 g /
m ² is preferable. If the basis weight is less than 30 g / m ² , the resulting nonwoven fabric will have insufficient mechanical properties and poor practicality, and will tend to be poor in form stability and dimensional stability. Conversely, if the basis weight exceeds 150 g / m ² , the processing energy in applying the high-pressure liquid flow treatment increases, and in some cases, the fibers are not sufficiently entangled with each other in the inner layer of the nonwoven web, resulting in low mechanical properties. It becomes a non-woven fabric.

The fibers having water absorbency can be obtained by a conventional method. On the other hand, composite synthetic short fibers can be efficiently produced by the following method. That is, for example, a spinneret forming the above-described core-in-sheath composite cross-sectional shape is preferably used, and two or more thermoplastic polymers having different melting points selected from the above-mentioned polymers are used as a spinning material. The melt spinning is performed at a melt spinning temperature corresponding to the melting point of the polymer to be melted. Next, the polymer stream discharged from the spinneret is
The yarn is drawn at a speed of 0 to 1200 m / min to obtain an undrawn yarn. Then, the obtained undrawn yarn is combined and subjected to a drawing treatment to obtain a drawn yarn. Then, the drawn yarn bundle that has been subjected to the drawing treatment is crimped by a press crimper, a fat and oil component for spinning is applied, and after being dried, it is cut into a predetermined fiber length to be a short fiber.

Next, a three-dimensional entanglement is formed between the constituent fibers by subjecting the obtained nonwoven web to a high-pressure liquid flow treatment. The high-pressure liquid flow treatment referred to here means, for example, that an injection hole having a hole diameter of 0.05 to 1.5 mm is formed at an injection hole interval of 0.05 to
A fluid jetted at a high pressure from a plurality of orifice heads arranged in one row or a plurality of rows with a diameter of 5 mm collide with a nonwoven web placed on a porous support member. And, by the force to draw in the constituent fibers at the time of collision,
It twists, bends, and turns other surrounding fibers to finely entangle the fibers and integrate them.

When the nonwoven web is subjected to three-dimensional confounding by a high-pressure liquid flow, the nonwoven web is placed on a moving porous support plate, and the jet pressure is 20 to 150 kg / cm ² G.
And a method of injecting the high-pressure liquid flow from the injection hole. The injection holes are preferably arranged in a row in a direction perpendicular to the direction of travel of the nonwoven web. When the high-pressure liquid flow impinges on the nonwoven web, the orifice head provided with the injection holes is supported by a porous support. It is preferable to make the column-shaped liquid jets uniformly collide with the jet holes at the same interval as the interval between the jet holes in a direction perpendicular to the traveling direction of the nonwoven web placed on the member.
The porous support member for supporting the nonwoven web is not particularly limited as long as the high-pressure liquid flow can pass through the nonwoven web, for example, a mesh screen such as a wire mesh or a perforated plate. Generally, water or hot water is used as the high-pressure liquid. The distance between the injection hole and the nonwoven web is 1-10c
m. If this distance is less than 1 cm, the formation of the nonwoven fabric obtained by this treatment tends to be disturbed. Conversely, if this distance exceeds 10 cm, the impact force when the liquid stream collides with the nonwoven web decreases. Three-dimensional confounding is not sufficiently performed.

After the high-pressure liquid flow treatment, a drying treatment is performed. At this time, it is preferable to first remove excess moisture from the nonwoven web after the treatment. A known method can be used to remove the excess water, and the excess water is mechanically removed to some extent using a squeezing device such as a mangle roll. Subsequently, the remaining moisture is removed using a drying device such as a suction band type hot air circulation type dryer, and a non-woven web whose shape is retained by three-dimensional entanglement is obtained as a roll product by a winder.

Next, the non-woven web subjected to three-dimensional entanglement obtained by the above-described method is subjected to a partial heat bonding treatment to heat-melt the low-melting polymer constituting the composite synthetic short fiber. The composite synthetic short fibers and the composite synthetic short fibers and the water-absorbing fibers are partially thermally bonded to each other.

This partial thermal bonding treatment is performed, for example, by using a so-called embossing roll having a surface engraved on a roll and a flat-surfaced roll. The shape of the sculpture of the pressed portion applied to the roll is not limited to a round shape, a square shape, a hexagonal shape, and the like, and various other shapes can be adopted. The area ratio of the portion to be thermally bonded to the nonwoven web, that is, the pressure contact area ratio, is in the range of 5 to 30%, more preferably 8 to 20%, with respect to the area of the web.
Good range. If the pressed area ratio is less than 5%, the mechanical properties, abrasion resistance, and dimensional stability cannot be improved, and the regulation of the bulk density of the nonwoven fabric tends to be insufficient. Conversely, if the pressed area ratio exceeds 30%, dimensional stability can be improved, but the flexibility of the nonwoven fabric is likely to be impaired.

In performing this partial thermal bonding treatment,
The melting point of the low-melting polymer constituting the composite synthetic short fiber is (T
m) ° C, (Tm-30) ° C to (Tm-5)
It is necessary to process at a temperature of ° C. Thereby, only the low melting point polymer constituting the composite synthetic short fiber contained in the nonwoven fabric is thermally melted, and flexibility can be maintained without thermally changing the high melting point polymer. When the treatment temperature is lower than (Tm-30) ° C., the heat bonding effect is thin and the mechanical properties are inferior, and the constituent fibers are liable to fall off.
When the temperature exceeds (Tm-5) ° C., the flexibility is inferior and a serious trouble that the web is taken by the heat bonding machine is likely to be caused.

In addition, as long as the flexibility and dimensional stability of the nonwoven fabric are not impaired, the above-described bonding method using ultrasonic waves or high frequency can be used as a partial thermal bonding method other than the above.

Further, in order to further improve the flexibility, a treatment using a flexible processing machine such as a cam fitting machine manufactured by Uenoyama Kiko Co., Ltd. may be performed as long as the effect of the thermal bonding is not impaired.

[0044]

Next, the present invention will be specifically described based on examples, but the present invention is not limited to only these examples. Incidentally, the measurement of various characteristic values in the examples,
It carried out by the following method.

(1) Melting point (° C.): Using a differential scanning calorimeter (manufactured by PerkinElmer; DSC-2 type), heating rate 2
The measurement was performed under the condition of 0 ° C./min, and the temperature at which an extreme value was obtained in the obtained melting endothermic curve was defined as the melting point (° C.).

(2) Relative viscosity of polyester: A mixture of phenol and ethane tetrachloride in an equal weight was used as a solvent, and 0.5 g of a sample was dissolved in 100 ml of the solvent.
It was measured by a conventional method under the condition of ° C.

(3) Melt index of polyethylene (g / 10 minutes): Measured according to the method described in ASTM-D-1238 (E) (hereinafter, the melt index is referred to as MI).

(4) Melt flow rate of polypropylene (g / 10 min): Measured according to the method described in ASTM-D-1238 (L) (hereinafter, the melt flow rate is referred to as MFR).

(5) Basis weight (g / m ² ): Five sample pieces each having a sample length of 10 cm and a sample width of 10 cm were prepared from the sample in the standard state, and after adjusting to equilibrium moisture, the weight (g) of each sample piece was obtained. ) Was weighed, and the average of the obtained values was converted per unit area to obtain the basis weight (g / m ² ).

(6) Tensile strength (kg / 5 cm width): JI
The measurement was carried out according to the method described in SL-1096A. That is, a sample having a sample length of 15 cm and a sample width of 5 cm was prepared for each 10 points, and the sample was measured using a constant-speed extension-type tensile tester (manufactured by Toyo Baldwin Co., Ltd .; Tensilon UTM-4-1-100). The gripping interval is 10cm and the pulling speed is 10c
Stretched at m / min. Then, the obtained cutting load value (k
g / 5cm width) to the tensile strength (kg / 5cm width)
And The tensile strength was measured in the machine direction (MD direction) of the nonwoven fabric.

(7) Flexibility, stiffness (g): Five specimens each having a specimen width of 5 cm and a specimen length of 5 cm are prepared, each specimen is bent in the longitudinal direction of the specimen, and both ends thereof are adhered to each other to form a cylinder. The shape was used as a measurement sample, and a constant-speed extension-type tensile tester (manufactured by Toyo Baldwin Co., Ltd .; Tensilon UTM-4-1-10)
Using (0), the sample was compressed at a speed of 5 cm / min, and the average value (g) of the stress under the maximum load was defined as the compression stiffness (g).

(8) Water absorption (mm / 10 minutes): JIS-
It was measured according to the Bilek method described in L-1096.

(9) Abrasion resistance (grade) of nonwoven fabric: A reciprocating friction test was performed 100 times using a Gakushin type friction tester, and a five-step evaluation was performed visually. In other words, the non-woven fabric with the least abrasion is class 5, and the non-woven fabric with the most abrasion is class 1.
During that time, grades 2 to 4 were graded.

(10) Bulk density of nonwoven fabric (g / cc): Five specimens each having a width of 10 cm and a length of 10 cm were prepared, and measured with a thickness measuring instrument (manufactured by Daiei Kagaku Seiki Seisakusho Co., Ltd.) at 4.5 g / cc. c
The thickness of each nonwoven fabric was measured by applying a load of m ² G, the average value was taken as the thickness (mm), and the value obtained by the following equation was taken as the bulk density of the nonwoven fabric.

Bulk density (g / cc) = [basis weight (g / m ²⁾
) / Thickness (mm)] × 1000

(11) Hollowness (%): The value obtained by the following equation according to FIG. 2 was used as the hollowness of the nonwoven fabric. Hollowness (%) = a ² / A ² × 100

(12) Flatness: The flatness was defined as W in the long axis and H in the short axis according to FIG. 3, and the value obtained by the following equation was defined as the flatness of the flat cross section fiber. Flatness = W / H

Example 1 A polyethylene having a melting point of 130 ° C. and an MI of 20 g / 10 min was used as a low melting polymer, and the melting point was 258.
Polyethylene terephthalate having a relative viscosity of 1.38 ° C. as a high-melting polymer, polyethylene terephthalate as a core component, and polyethylene as a sheath component. Was used to obtain a composite synthetic short fiber. That is, the compounding ratio of both polymers was set to 50/50 (weight ratio), and the single hole discharge amount was set to 0.6.
Melt spinning was performed at 8 g / min and a melting temperature of 285 ° C. After cooling the yarn spun from the core-sheath composite spinneret, the yarn was wound up as an undrawn yarn through a roll having a take-up speed of 1000 m / min. Next, the undrawn yarn tow was stretched 3.2 times using a known stretching machine, guided to a push-in type crimper, crimped, and then cut to 38 mm. The single fiber fineness of the drawn short fibers was 2 denier.

Next, bleached cotton having an average fineness of 1.5 denier and an average fiber length of 24 mm and the above-mentioned composite synthetic short fiber were uniformly mixed at a ratio of cotton bleached cotton / composite synthetic short fiber = 90/10 (weight%). And a non-woven web having a basis weight of 60 g / m ² was prepared using a random card machine.

Subsequently, the obtained nonwoven web was placed on a moving 70-mesh metal net, and the injection hole diameter was 0.1 mm and the injection hole interval was 0.6 mm from a position 50 mm above the nonwoven web layer. From the injection holes arranged in a row with a high-pressure water flow at an injection pressure of 70 kg / cm ² G to obtain a densely entangled nonwoven web. Next, excess water was removed from the entangled nonwoven web by a mangle, which is a known water removing device, dried by a dryer at 90 ° C., and wound up in a roll.

Then, a partial heat bonding treatment was performed. At the time of the heat bonding treatment, an embossing roll engraved with a pressure contact area ratio of 10% and a flat-surfaced roll were used, the temperature of the roll surface was 120 ° C., and the linear pressure between the rolls was 30 kg / roll.
cm, a nonwoven fabric was obtained.

Table 1 shows the performance and the like of the obtained nonwoven fabric.

[0063]

[Table 1]

Example 2 The blending ratio of bleached cotton of cotton and composite synthetic staple fiber in Example 1 was calculated as follows: cotton bleached cotton / composite synthetic staple fiber = 70/30.
(% By weight). Then, a nonwoven fabric having a basis weight of 60 g / m ² was prepared under the same conditions as in Example 1 except for the above.

Table 1 shows the performance and the like of the obtained nonwoven fabric.

Example 3 The ratio of bleached cotton and composite synthetic staple fiber in Example 1 was calculated as follows: cotton bleached cotton / composite synthetic staple fiber = 50/50.
(% By weight). Then, a nonwoven fabric having a basis weight of 60 g / m ² was prepared under the same conditions as in Example 1 except for the above.

Table 1 shows the performance and the like of the obtained nonwoven fabric.

Example 4 A copolymer of terephthalate acid / isophthalic acid = 60/40 (mol%) having a melting point of 110 ° C. and a relative viscosity of 1.40 was used as a low-melting polymer, and was used as a high-melting polymer. Using the same polyethylene terephthalate as in Example 1, using a composite spinneret having a solid core-sheath type composite cross-sectional shape in which polyethylene terephthalate is disposed in the core component and copolymerized polyester is disposed in the sheath component, a composite spinneret is obtained. Fiber was obtained. That is, the mixing ratio of both polymers is 5% by weight.
The melt spinning was performed at 0:50, the single hole discharge rate was 0.72 g / min, and the melting temperature was 285 ° C. After cooling the yarn spun from the core-sheath composite spinneret, the yarn was wound up as an undrawn yarn through a roll having a take-up speed of 1000 m / min. Next, the undrawn yarn tow was drawn 3.4 times using a known drawing machine, guided to a push-in type crimper to give crimp, and then cut into 38 mm. The single fiber fineness of the drawn short fibers was 2 denier.

Next, the bleached cotton of cotton used in Example 1 and the above-mentioned composite synthetic staple fiber were uniformly mixed at a ratio of cotton bleached cotton / composite synthetic staple fiber = 70/30 (% by weight), and a random card was prepared. A nonwoven web having a basis weight of 60 g / m ² was prepared using a machine.

Subsequently, the obtained nonwoven web was used in Example 1.
Under the same conditions as described above, a confounding treatment and a drying treatment were performed. Then, a partial heat bonding process was performed. During the heat bonding treatment, the temperature of the roll surface was set to 100 ° C. Other than that, a nonwoven fabric was prepared under the same conditions as in Example 1.

Table 1 shows the performance and the like of the obtained nonwoven fabric.

Example 5 Polypropylene having a melting point of 160 ° C. and an MFR of 50 g / 10 min was used as a low melting polymer, and the same polyethylene terephthalate as in Example 1 was used as a high melting polymer.
A composite synthetic short fiber was obtained using a composite spinneret having a solid core-sheath composite cross-sectional shape in which polyethylene terephthalate was disposed in the core component and polypropylene was disposed in the sheath component. That is, the mixing ratio of both polymers is 50: 5 by weight ratio.
0, the single hole discharge rate was 0.65 g / min, and the melting temperature was 28.
At 5 ° C., melt spinning was performed. Then, after cooling the yarn spun from the core-sheath type composite spinneret, the take-up speed becomes 1
It was wound up as an undrawn yarn through a roll of 000 m / min. Next, the undrawn yarn tow was drawn 3.1 times using a known drawing machine, guided to a push-in type crimper to give crimp, and then cut into 38 mm. The single fiber fineness of the drawn short fibers was 2 denier.

Next, the bleached cotton of cotton used in Example 1 and the above-mentioned composite synthetic short fiber were combined with cotton bleached cotton / composite synthetic short fiber =
The cotton was uniformly mixed at a ratio of 70/30 (% by weight), and a nonwoven web having a basis weight of 60 g / m ² was prepared using a random card machine.

Subsequently, the obtained nonwoven web was used in Example 1.
Under the same conditions as described above, a confounding treatment and a drying treatment were performed. Then, a partial heat bonding process was performed. During the heat bonding treatment, the temperature of the roll surface was set to 150 ° C. Other than that, a nonwoven fabric was prepared under the same conditions as in Example 1.

Table 1 shows the performance and the like of the obtained nonwoven fabric.

Example 6 The same polyethylene as in Example 1 was used as the low melting polymer, and the same polypropylene as in Example 5 was used as the high melting polymer, polypropylene was used as the core component, and polyethylene was used as the sheath component. Was used to obtain a composite synthetic staple fiber using a composite spinneret having a solid core-sheath composite cross-sectional shape. That is, the mixing ratio of both polymers is 50: 5 by weight ratio.
0, the single hole discharge rate was 0.59 g / min, and the melting temperature was 23.
At 0 ° C., melt spinning was performed. Then, after cooling the yarn spun from the core-sheath type composite spinneret, the take-up speed becomes 1
It was wound up as an undrawn yarn through a roll of 000 m / min. Next, the undrawn yarn tow was stretched 2.8 times using a known stretching machine, guided to a push-in type crimper, crimped, and then cut to 38 mm. The single fiber fineness of the drawn short fibers was 2 denier.

Next, the bleached cotton of cotton used in Example 1 and the above-mentioned composite synthetic staple fiber were uniformly mixed in a ratio of cotton bleached cotton / composite synthetic staple fiber = 70/30 (% by weight), and a random card was prepared. A nonwoven web having a basis weight of 60 g / m ² was prepared using a machine.

Subsequently, the obtained nonwoven web was used in Example 1.
Under the same conditions as described above, a confounding treatment and a drying treatment were performed. Then, a partial heat bonding treatment was performed under the same conditions as in Example 1 to prepare a nonwoven fabric.

Table 1 shows the performance and the like of the obtained nonwoven fabric.

Example 7 The same polyethylene as in Example 1 was used as the low-melting polymer, and the same polyethylene as the high-melting polymer, polyethylene terephthalate as in Example 1, polyethylene terephthalate as the core component, and the sheath component A composite synthetic short fiber was obtained using a composite spinneret having a hollow core-sheath type composite cross-sectional shape in which polyethylene was disposed. That is, the mixing ratio of both polymers was set to 50:50 by weight, and the single hole discharge amount was set to 1.05.
The melt spinning was performed at a melting point of 285 ° C. and a melting temperature of 285 ° C. After cooling the yarn spun from the core-sheath composite spinneret, the yarn was wound up as an undrawn yarn through a roll having a take-up speed of 1000 m / min. Next, the undrawn yarn tow was stretched 3.3 times using a known stretching machine, guided to a push-in type crimper, crimped, and then cut to 38 mm. The single fiber fineness of the drawn short fibers was 3 denier, and the hollowness was 17%.

Next, the bleached cotton of cotton used in Example 1 and the composite synthetic short fiber having the hollow core-sheath type composite cross-sectional shape were combined with the cotton bleached cotton / hollow core-sheath composite composite short fiber =
The cotton was uniformly mixed at a ratio of 70/30 (% by weight), and a nonwoven web having a basis weight of 60 g / m ² was prepared using a random card machine.

Subsequently, the obtained nonwoven web was used in Example 1.
Under the same conditions as described above, a confounding treatment and a drying treatment were performed. Then, a partial heat bonding treatment was performed under the same conditions as in Example 1 to prepare a nonwoven fabric.

Table 2 shows the performance and the like of the obtained nonwoven fabric.

[0084]

[Table 2]

Example 8 Using the same polyethylene terephthalate as in Example 1,
Synthetic short fibers having a large fineness were obtained using a spinneret capable of obtaining a single-phase round cross-sectional shape. That is, the single hole discharge amount is 4.32.
The melt spinning was performed at a melting point of 285 ° C. and a melting temperature of 285 ° C. After cooling the yarn spun from the spinneret, the yarn was taken up as an undrawn yarn through a roll having a take-up speed of 1000 m / min. Next, the undrawn yarn tow was drawn to 4.1 times using a known drawing machine, guided to a push-in type crimper to give crimp, and then cut into 51 mm.
The single fiber fineness of the drawn short fibers was 10 denier.

Next, using the bleached cotton of cotton used in Example 1 and the composite synthetic short fiber having a solid core-sheath type composite cross section, the synthetic short fiber having the fineness was added thereto, and the cotton bleached cotton was added. / Solid core-sheath type composite cross-section composite synthetic short fiber / large fineness synthetic short fiber = 60/20/20 (weight%), uniformly mixed, and a basis weight of 60 g / m using a random card machine.
^Two nonwoven webs were made. Subsequently, the obtained nonwoven web was subjected to a entanglement treatment and a drying treatment under the same conditions as in Example 1.

Then, a partial heat bonding treatment was performed under the same conditions as in Example 1 except that the temperature of the roll surface was set to 123 ° C., to prepare a nonwoven fabric. Table 2 shows the performance and the like of the obtained nonwoven fabric.

Example 9 A composite short fiber composed of bleached cotton used in Example 1 and a hollow core-sheath composite cross section used in Example 7 and Example 8 were used.
The synthetic staple fiber having the fineness used in
Hollow-core sheath type composite cross-section composite synthetic short fiber / large fineness synthetic short fiber = 60/20/20 (wt%)
A nonwoven web having a basis weight of 60 g / m ² was prepared using a random card machine.

Subsequently, the obtained nonwoven web was prepared in Example 1.
Under the same conditions as described above, a confounding treatment and a drying treatment were performed. Then, the temperature of the roll surface is set to 123 ° C.
A nonwoven fabric was prepared under the same conditions as in Example 1 except that the above conditions were satisfied.

Table 1 shows the performance and the like of the obtained nonwoven fabric.

Example 10 Using the same polyethylene terephthalate as in Example 1,
Synthetic short fibers were obtained by using a spinneret capable of obtaining a single-phase flat type cross-sectional shape. That is, the single hole discharge amount is set to 0.63 g /
The melt spinning was performed at a melting temperature of 285 ° C. for one minute. After cooling the yarn spun from the spinneret, the yarn was taken up as an undrawn yarn through a roll having a take-up speed of 1000 m / min. Next, the undrawn yarn tow was stretched to 3.0 times using a known stretching machine, guided to a push-in type crimper, crimped, and then cut to 38 mm. The single fiber fineness of the drawn short fibers was 2 denier and the flatness was 7.2.

Next, similarly to the bleached cotton of the cotton used in Example 1, the composite synthetic short fiber having the solid core-sheath composite cross section used in Example 1 and the synthetic short fiber having the flat type cross section used in Example 1 were used. Is obtained by bleaching cotton / solid core-sheath composite composite composite short fiber / flat composite synthetic short fiber = 60/20/20
(Weight%), and a non-woven web having a basis weight of 60 g / m ² was prepared using a random card machine.

Subsequently, the obtained nonwoven web was used in Example 1.
Under the same conditions as described above, a confounding treatment and a drying treatment were performed. Then, the temperature of the roll surface is set to 123 ° C.
A nonwoven fabric was prepared under the same conditions as in Example 1 except that the above conditions were satisfied.

Table 2 shows the performance and the like of the obtained nonwoven fabric.

Example 11 A composite synthetic short fiber comprising bleached cotton used in Example 1 and a hollow core-sheath type composite sectional shape used in Example 7 was used.
The synthetic short fiber having the flat cross-sectional shape used in Example 1 was mixed with cotton bleached cotton / hollow core / sheath composite cross-sectional composite short fiber / flat synthetic short fiber = 60/20/20 (% by weight). And a nonwoven web having a basis weight of 60 g / m ² was prepared using a random card machine.

Subsequently, the obtained nonwoven web was used in Example 1.
Under the same conditions as described above, a confounding treatment and a drying treatment were performed. Then, the temperature of the roll surface is set to 123 ° C.
A nonwoven fabric was prepared under the same conditions as in Example 1 except that the above conditions were satisfied.

Table 2 shows the performance and the like of the obtained nonwoven fabric.

Example 12 Using the composite synthetic staple fiber of Example 1 and rayon having a single fiber fineness of 2 denier and a fiber length of 38 mm, the mixing ratio was set to 70/30 (weight%). Blend uniformly and use a random card machine to obtain a basis weight of 60 g /
you create a nonwoven web m ^2.

Subsequently, the obtained nonwoven web was prepared in Example 1.
Under the same conditions as described above, a confounding treatment and a drying treatment were performed. Then, a partial heat bonding treatment was performed under the same conditions as in Example 1 to produce a nonwoven fabric.

Table 2 shows the performance and the like of the obtained nonwoven fabric.

Example 13 Using the same polyethylene terephthalate as in Example 1,
Synthetic short fibers of fine fineness were obtained using a spinneret capable of obtaining a single-phase round cross-sectional shape. That is, the single hole discharge amount is set to 0.27.
The melt spinning was performed at a melt temperature of 285 ° C. and a melt temperature of 285 ° C.
After cooling the yarn spun from the spinneret, the yarn was taken up as an undrawn yarn through a roll having a take-up speed of 1000 m / min.

Next, the undrawn yarn tow was drawn to 2.6 using a known drawing machine, guided to a push-in type crimper, crimped, and then cut to 38 mm. The single fiber fineness of the drawn short fibers was 1 denier.

Next, the bleached cotton of cotton used in Example 1 and the composite synthetic short fiber having a solid core-sheath type cross-sectional shape were combined with cotton bleached cotton / solid core-sheath type composite cross-sectional synthetic short fiber / fine fineness synthetic short fiber. Fibers were uniformly mixed at a ratio of 60/20/20 (weight%), and a nonwoven web of 60 g / m ² was prepared using a random card machine.

Subsequently, the obtained nonwoven web was used in Example 1.
Under the same conditions as described above, a confounding treatment and a drying treatment were performed. Then, the temperature of the roll surface is set to 123 ° C.
A nonwoven fabric was prepared under the same conditions as in Example 1 except that the above conditions were satisfied.

Table 2 shows the performance and the like of the obtained nonwoven fabric.

The nonwoven fabric obtained in each of Examples 1 to 6 contains a solid core-sheath type composite fiber in which each of the polymers constituting the core component and the sheath component has a melting point difference of 30 ° C. or more. Partial thermal bonding is performed leaving the entangled portion, and since the temperature of the thermal bonding is equal to or lower than the melting point of the high melting point polymer, it has excellent mechanical properties, and also has excellent water absorption, abrasion resistance, The bulkiness was sufficiently exhibited, and the polymer did not thermally damage the high melting point polymer but had flexibility.

The nonwoven fabric obtained in Example 7 was excellent in bulkiness because a hollow core-sheath type composite fiber was used as the composite synthetic short fiber. The nonwoven fabric obtained in Examples 8 to 9 is
As a composite synthetic short fiber, a solid or hollow core-sheath composite fiber, a short fiber having a large fineness, and cotton were mixed, so that the mechanical properties and flexibility were slightly inferior, but the bulkiness was further excellent.

The nonwoven fabrics obtained in Examples 10 to 11 were prepared by mixing solid or hollow core-sheath composite fibers with short fibers having a flat cross section exhibiting excellent confounding ability and cotton as composite synthetic short fibers. Although it was slightly inferior in flexibility and bulkiness, it was particularly excellent in mechanical properties.

The nonwoven fabric obtained in Example 12 was a mixture of solid core-sheath type composite fiber and rayon instead of cotton, so that the nonwoven fabric was slightly inferior in water absorption and excellent in other performances.

The nonwoven fabric obtained in Example 13 was used by mixing a solid core-sheath composite fiber and a short fiber having a fine fineness as a composite synthetic short fiber, and further mixing cotton.
Although the bulkiness was slightly inferior, the flexibility and mechanical properties were excellent.

Comparative Example 1 The same nonwoven web of bleached cotton and composite synthetic staple fiber as in Example 2 was subjected to three-dimensional entanglement under the same conditions as in Example 1, and dried with a dryer. went. Then, a nonwoven web having a basis weight of 60 g / m ² was prepared without performing a partial heat bonding treatment.

Table 3 shows the performance and the like of the obtained nonwoven fabric.

[0113]

[Table 3]

Comparative Example 2 The blending ratio of bleached cotton cotton and composite synthetic staple fiber used in Example 1 was set to be cotton bleached cotton / composite synthetic staple fiber = 30/70 (% by weight). Then, a nonwoven fabric having a basis weight of 60 g / m ² was prepared under the same conditions as in Example 1 except for the above.

Table 3 shows the performance and the like of the obtained nonwoven fabric.

Comparative Example 3 The ratio of the cotton blended cotton bleached cotton and the composite synthetic staple fiber in Example 1 was set to be cotton bleached cotton / composite synthetic staple fiber = 95/5 (% by weight). Then, a nonwoven fabric having a basis weight of 60 g / m ² was prepared under the same conditions as in Example 1 except for the above.

Table 3 shows the performance and the like of the obtained nonwoven fabric.

Comparative Example 4 In the partial heat bonding treatment in Example 2, the temperature of the roll surface was set to 135 ° C., which was higher than the melting point (130 ° C.) of polyethylene as a low melting point polymer. Otherwise, the basis weight was 60 g / m ^{2 under the} same conditions as in Example 1.
Was prepared.

Table 3 shows the performance and the like of the obtained nonwoven fabric.

Comparative Example 5 In the partial thermal bonding treatment in Example 2, the temperature of the roll surface was set to 85 ° C. Then, a nonwoven fabric having a basis weight of 60 g / m ² was prepared under the same conditions as in Example 1 except for the above.

Table 3 shows the performance and the like of the obtained nonwoven fabric.

Since the nonwoven fabric obtained in Comparative Example 1 was not subjected to a partial heat bonding treatment, it was excellent in flexibility and bulkiness, but remarkably inferior in mechanical properties and abrasion resistance. The nonwoven fabric obtained in Comparative Example 2 was inferior in bulkiness, flexibility, and water absorption because the cotton mixing ratio of cotton, which is a natural fiber, was too low.

The nonwoven fabric obtained in Comparative Example 3 had an insufficient bonding function even when subjected to a partial heat bonding treatment because the mixing ratio of the solid core-sheath type conjugate fiber which is a conjugate synthetic short fiber was too low.
The mechanical properties and wear resistance were remarkably poor.

In the non-woven fabric obtained in Comparative Example 4, the roll surface temperature was set higher by setting the difference between the roll surface temperature and the low-melting polymer to + 5 ° C. in the heat bonding step. It was taken up in a roll and the desired nonwoven fabric could not be obtained.

In the heat bonding step, the nonwoven fabric obtained in Comparative Example 5 had a roll surface temperature 45 ° C. lower than the melting point of the low-melting polymer, so that the nonwoven fabric was remarkably inferior in mechanical properties and abrasion resistance.

[0126]

According to the present invention, three-dimensional entanglement is obtained in a state where the fiber having water absorption and the conjugate synthetic short fiber are mixed, and the fibers having this three-dimensional entanglement by partial heat bonding are used. Since the low melting point polymer is thermally fused, excellent strength and dimensional stability of the nonwoven fabric can be obtained by three-dimensional entanglement of fibers and thermal fusion. In addition to the three-dimensional entanglement process, the partial thermal bonding process is performed, and the non-partial thermal bonding portion is subjected to the three-dimensional entanglement process. It is possible to prevent and improve the wear resistance, and also to improve the wear resistance in the partially heat-bonded part. Furthermore, a nonwoven fabric rich in water absorption can be obtained because it contains fibers having water absorption such as natural fibers and regenerated fibers, and thus a nonwoven fabric that can be effectively used in various applications can be obtained.

[Brief description of the drawings]

FIG. 1 is a diagram showing a fiber cross section of a composite synthetic short fiber having a core-sheath composite cross section according to the present invention.

FIG. 2 is a view showing a fiber cross section of a composite synthetic short fiber having a hollow core-sheath type composite cross section according to the present invention.

FIG. 3 is a diagram showing a fiber cross section of a synthetic short fiber having a flat cross section according to the present invention.

[Explanation of symbols]

 1 sheath component 2 core component 3 hollow part

Continued on the front page (51) Int.Cl. ⁶ Identification code FI D01F 8/14 D01F 8/14 Z

Claims (8)

[Claims] Claims: 1. A three-dimensional entangled fiber in which a fiber having a water-absorbing property and a conjugated synthetic staple fiber are mixed, wherein the conjugated staple fiber is composed of two or more kinds of thermoplastic polymers having different melting points, The thermoplastic polymer having the lowest melting point of the two or more thermoplastic polymers is exposed on the surface of the composite synthetic short fiber, and the fibers having the three-dimensional entanglement are separated from each other by the thermoplastic polymer having the lowest melting point. Characterized by having a partially heat-bonded portion which is heat-sealed. 2. A solid core-sheath comprising a composite synthetic short fiber having a thermoplastic polymer having a lowest melting point as a sheath component and a thermoplastic polymer having a melting point higher than that of the thermoplastic polymer by 25 ° C. or more as a core component. The nonwoven fabric according to claim 1, wherein the nonwoven fabric has one of a mold composite cross section and a hollow core-sheath composite cross section having a hollow portion inside a fiber cross section in the solid core-sheath composite cross section. 3. The mixing ratio of the water-absorbing fiber and the composite synthetic short fiber is (water-absorbing fiber) / (composite synthetic short fiber) = 50/50 to 90/10 (% by weight). The nonwoven fabric according to claim 1 or 2, wherein 4. The fiber having water absorbency is cotton, ramie,
4. A natural fiber such as wool or silk cut into short fibers and a regenerated fiber such as viscose rayon, cuprammonium rayon, or solvent spun rayon. The nonwoven fabric according to any one of the above. 5. The nonwoven fabric according to claim 1, wherein the single-filament fineness of the conjugate synthetic short fiber is 1.5 denier or more and less than 7 denier. 6. The nonwoven fabric according to claim 5, comprising synthetic short fibers of 1 denier or more and 15 denier or less. 7. The nonwoven fabric according to claim 1, comprising synthetic short fibers having a flat cross section. 8. A synthetic short fiber composed of two or more kinds of thermoplastic polymers having different melting points, wherein the thermoplastic polymer having the lowest melting point among the two or more kinds of thermoplastic polymers is exposed to the fiber surface and a water absorbing material. A nonwoven web is formed by blending with fibers having properties to form a nonwoven web, and then the nonwoven web is subjected to a high-pressure liquid flow treatment to form a three-dimensional entanglement between the constituent fibers. When the melting point of the thermoplastic polymer having the lowest melting point that constitutes the composite synthetic short fiber is (Tm) ° C, the partial thermal bonding treatment is performed at a temperature of (Tm-30) ° C to (Tm-5) ° C. A method for producing a nonwoven fabric, characterized in that the nonwoven fabric is applied.