JPH11247059A - Nonwoven fabric and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a spun lace nonwoven fabric having excellent mechanical properties and dimensional stability from a nonwoven web composed of ultrafine split staple fibers and heat-adhesive staple fibers by heat-welding the heat- adhesive staple fibers to fix the three-dimensionally interlocked state of the constituent fibers. SOLUTION: A nonwoven fabric having an areal density of 20-200 g/m<2> is produced by blending 90-60 wt.% of splittable binary conjugate staple fibers composed of mutually incompatible fiber-forming polymers such as polyolefin/ polyamide and 10-40 wt.% of heat-adhesive staple fibers, carding the mixture to form a nonwoven web, placing the web on a porous substrate, subjecting to a high-pressure fluid flow treatment to split the above conjugate staple fibers to ultrafine split staple fibers having a single fiber fineness of <=0.5 de and three-dimensionally interlock the constituent fibers, heat-treating the product at a temperature to melt or soften the heat-adhesive staple fibers and fixing the above three-dimensional interlocked state by the hot-welding of the heat- adhesive fibers.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a spunlaced nonwoven fabric.

[0002]

2. Description of the Related Art Spunlaced nonwoven fabrics in which the constituent fibers are three-dimensionally entangled by the action of a high-pressure liquid flow have large inter-fiber voids and are excellent in flexibility. Used for applications. As the material of the constituent fibers, natural fibers, synthetic fibers, and the like are appropriately selected and used according to various uses. However, since spunlaced nonwoven fabric is formed into a nonwoven fabric only by interlacing fibers, it is easily deformed, fuzzed, and pulled out of fibers due to tension and friction, and is sufficiently excellent in terms of form stability. Is hard to say.

[0003]

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and has as its object to obtain a spunlaced nonwoven fabric having excellent mechanical properties and dimensional stability.

[0004]

The present invention attains the above object and has the following constitution. That is,
The present invention is a nonwoven fabric consisting of ultrafine split short fibers expressed by splitting split type bicomponent conjugate short fibers composed of mutually incompatible fiber-forming polymers, and heat-adhesive short fibers,
The gist of the present invention is a nonwoven fabric characterized in that the constituent fibers are three-dimensionally entangled and the entangled form is fixed by heat fusion of the heat-adhesive short fibers.

[0005] The present invention also relates to a splitting type bicomponent conjugate short fiber composed of mutually incompatible fiber-forming polymers and a heat-adhesive staple fiber in a mixing ratio of 90 to 60/10 to 40 (% by weight).
A non-woven web is obtained by mixing the non-woven web, and the non-woven web is placed on a porous support material and subjected to a high-pressure liquid flow treatment. Non-woven fabric characterized by three-dimensionally entangled with each other, heat-treated at a temperature at which the heat-bondable short fibers melt or soften, and heat-fused the heat-bondable short fibers to fix the entangled form. Of the present invention.

[0006]

Next, the present invention will be described in detail.
First, the splittable bicomponent conjugate short fibers used in the present invention will be described. The split type bicomponent conjugate short fibers are made of mutually incompatible fiber-forming polymers. The incompatibility with each other is to make it easy to split the composite staple fiber when subjected to impact.

The fiber-forming polymer constituting the splittable bicomponent conjugate short fiber includes a polyolefin polymer, a polyamide polymer, a polyester polymer, and the like.
Examples of incompatible polymer combinations include polyolefin / polyamide, polyolefin / polyester, polyamide / polyester, and the like. However, these are typical examples, and other various combinations may be arbitrarily employed.

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 are other olefins and / or small amounts (up to about 10% by weight of polymer weight) of other ethylenically unsaturated monomers such as butadiene, isoprene, 1,3-pentadiene, styrene, α
-May be copolymerized with similar ethylenically unsaturated monomers such as methylstyrene. Particularly in the case of polyethylene, up to about 10% by weight of the polymer weight of propylene, 1-
Butene, 1-hexene, 1-octene or similar higher α
-Copolymerized with olefin is preferred because of improved spinning properties.

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, and alcohol components as ethylene glycol, diethylene glycol,
1,4-butanediol, neopentyl glycol,
A homopolyester or a copolyester synthesized from a diol compound such as 1,4-cyclohexanedimethanol, and the homopolyester or the copolyester is added to paraoxybenzoic acid, 5-sodium sulfoisophthalic acid, polyalkylene glycol,
Pentaerythritol, bisphenol A or the like may be added or copolymerized.

[0010] 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 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, an antibacterial agent, and a hydrophilic agent may be added.

As a specific example of the splittable bicomponent conjugate short fibers, those having a cross section as shown in FIGS. 1 to 4 are preferable. In these, both components of the fiber-forming polymer constituting the splittable bicomponent conjugate short fiber are both exposed on the surface of the fiber, and in the cross section of the fiber, one component is split by the other component. It is divided into delicate shapes.

The single yarn fineness of the split type bicomponent conjugate short fiber is as follows:
Preferably it is 1 to 12 denier. Single yarn fineness is 1
When it is less than denier, the discharge amount per single hole of the spinneret during melt spinning is reduced, and the production amount tends to decrease, and in order to improve the production amount, the number of holes in the spinneret is increased. Then, the spinning process becomes unstable. On the other hand, if the single yarn fineness exceeds 12 denier, it tends to be difficult to take off due to insufficient cooling of the melt-spun yarn, and to promote the cooling of the yarn, the number of holes in the spinneret is reduced. , The production volume decreases.

The splittable bicomponent conjugate short fibers are split at the boundary between the two components by a split splitting process, and at least one of the ultrafine split short fibers made of a polymer and the other is divided at least. Express. In the present invention, the single fiber fineness of at least the ultrafine split short fibers expressed is preferably 0.5 denier or less, more preferably 0.05 to 0.3 denier, and still more preferably 0.1 to 0.3 denier. is there.
If the single-fiber fineness is less than 0.05 denier, spinning is practically difficult, and it is difficult to obtain a splittable bicomponent conjugate short fiber at a reasonable cost. In addition, there is a tendency that it is difficult to sufficiently perform split splitting. On the other hand, if it exceeds 0.5 denier,
It is difficult to obtain the effect of the ultrafine fiber aimed at by the present invention.
For example, when such a nonwoven fabric is used as a wiping material, it tends to be inferior in wiping of microscopic dirt, and when used in contact with a human body, it feels hard and feels coarse and hard.

The split type bicomponent conjugate short fibers are 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, applying an oil agent, and as an undrawn yarn through a take-off roller. It is wound on a winder. Pickup roller speed is 500m / min ~
2000 m / min. A plurality of wound undrawn yarns are aligned and drawn between a group of rollers having different peripheral speeds by a known drawing machine. Next, the drawn tow is crimped by a press-type crimping device, and then cut into a predetermined fiber length to obtain short fibers. The stretch tow may be subjected to heat setting at a temperature equal to or lower than the melting point of the material depending on the required use.

The heat-adhesive short fibers used in the present invention are fibers having at least a heat-adhesive component on the fiber surface. The heat-adhesive short fibers are fused by heat treatment to fix the entangled state of the constituent fibers. I do. The heat-adhesive component of the heat-adhesive short fibers has a melting point or softening point lower than the melting point of the polymer constituting the splittable bicomponent conjugate short fibers, which is the main fiber, by 30 ° C. or more. If the difference between the two is less than 30 ° C,
When heat-bonding the heat-adhesive short fibers, even ultrafine split short fibers developed from the split type bicomponent conjugate short fibers may be softened and melted, which is not preferable.

The form of the heat-adhesive short fiber may be any form having a heat-adhesive component on at least the fiber surface.
Single-phase type consisting only of the heat-adhesive component, laminated type of the heat-adhesive component and another polymer, a core in which the heat-adhesive component is disposed in the sheath and the other polymer is disposed in the core A sheath type is exemplified. In the present invention, the polymer disposed on the core is 3
A core-in-sheath composite fiber in which a polymer having a melting point or softening point lower than 0 ° C. or lower (a heat-adhesive component) is disposed in a sheath portion is preferably used. The core-sheath type composite fiber is preferable because only the sheath part functions as an adhesive for fusing constituent fibers together, and the core part maintains the form of the fiber and contributes to improvement in flexibility.

The heat-adhesive short fibers may be mixed in the nonwoven fabric in such an amount that the object of the present invention can be achieved.
It is good to mix by weight%. Cotton mixing ratio of heat-adhesive short fiber is 1
If the content is less than 0% by weight, the three-dimensional entangled structure of the nonwoven fabric is sufficiently fixed, and a nonwoven fabric having excellent wear resistance and durability cannot be obtained. On the other hand, if it exceeds 40% by weight, the proportion of the ultrafine split fibers occupying the nonwoven fabric decreases, and the texture of the ultrafine split fibers is unfavorably deteriorated.

The basis weight of the nonwoven fabric of the present invention is not particularly limited, but is in the range of 20 to 200 g / m ² . 20 basis weight
g / m is less than ² tends to become poor in nonwoven formation, the basis weight exceeds 200 g / m ^2, when the high-pressure liquid jet treatment, sufficient entanglement to the fibers each other in the inner layer of nonwoven and split split fiber It is difficult to be done.

Next, the method for producing a nonwoven fabric of the present invention will be described. In the present invention, first, the splitting type bicomponent conjugate short fiber and the heat-adhesive short fiber are mixed at a cotton mixing ratio of 90-60 / 10-10
(Weight%), and a nonwoven 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 select various degrees of arrangement of the constituent fibers. As the arrangement pattern of the constituent fibers, a parallel web in which the constituent fibers are arranged in one direction, a web in which the parallel webs are cross-laid, a random web in which the constituent fibers are randomly arranged, or a semi-random web in which both are moderately arranged. No.

Next, the obtained nonwoven web is subjected to a high-pressure liquid flow treatment to split the splittable bicomponent conjugate short fibers to express ultrafine split short fibers and to make the constituent fibers three-dimensionally. Confound. The three-dimensional confounding referred to herein means that the fibers constituting the nonwoven web 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. What you do.

The high-pressure liquid flow processing will be described. As a high-pressure liquid flow device for performing the treatment, for example, a large number of injection holes having a hole diameter of 0.05 to 1.5 mm, particularly 0.1 to 0.4 mm are arranged in a line or a plurality of lines at a hole interval of 0.05 to 5 mm. Use an arrayed device. 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 a nonwoven web placed on a porous support member. Split type bicomponent conjugate short fibers are impacted by high pressure liquid flow,
Ultrafine split short fibers are developed, and the constituent fibers are three-dimensionally entangled and integrated. At this time, the entanglement of the fibers becomes dense and strong due to the expression of ultrafine split short fibers.

The jet holes are arranged in rows in a direction perpendicular to the direction of travel of the nonwoven web. As a high pressure liquid flow,
Room temperature or hot water can be used. The distance between the injection holes and the nonwoven web is preferably between 10 and 150 mm. If this distance is less than 10 mm, the formation of the nonwoven fabric obtained by this treatment is disturbed, while the distance is 150 mm.
If it exceeds mm, the impact force when the liquid stream collides with the nonwoven web tends to decrease, and the split splitting and entanglement integration tend not to be sufficiently performed.

The processing pressure of this high-pressure liquid stream is controlled by the required performance of the nonwoven fabric, but is generally in the range of 20 to 20.
A high pressure liquid stream of 0 kg / cm ² G is preferably ejected. In addition, depending on the basis weight of the nonwoven web to be treated, etc., within the range of the treatment pressure, it is possible to obtain a nonwoven fabric which is bulky and excellent in flexibility when the treatment pressure is low, and is constituted when the treatment pressure is high. A nonwoven fabric in which the entanglement of the fibers is dense and strong can be obtained. 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 nonwoven fabric targeted by the present invention cannot be obtained.
However, the nonwoven fabric of the present invention also includes nonwoven fabrics in which split bicomponent conjugate short fibers are not sufficiently split and partially remain. Conversely, if the pressure of the high-pressure liquid flow exceeds 200 kg / cm ² G, the constituent fibers are cut in an extreme case by impact with water pressure, and the resulting nonwoven fabric tends to have fluff on the surface.

The porous support member for supporting the nonwoven web 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. By appropriately selecting the structure of the mesh screen or the like, it is possible to impart a pattern or an opening to the nonwoven fabric.

After the high-pressure liquid flow treatment is performed from one side of the nonwoven web, the entangled nonwoven web is subsequently turned over and subjected to the high-pressure liquid flow treatment, whereby the nonwoven fabric densely entangled on both sides is obtained. Since it can be obtained, it may be applied to a nonwoven web having a large basis weight or the like according to the use of the nonwoven fabric.

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

Next, the three-dimensionally entangled nonwoven fabric is subjected to a heat treatment using a heat treatment device at a temperature at which the heat-bondable short fibers are melted or softened, and the heat-bondable short fibers are heat-fused to form the constituent fibers. The three-dimensional entangled form is fixed by heat bonding. As a heat treatment apparatus to be used, a dry heat hot air circulation system is effectively used. Since the nonwoven fabric three-dimensionally entangled has a stable form as a nonwoven fabric, heat treatment is performed without the constituent fibers being scattered by hot air, and the three-dimensional entangled form is fixed by thermal bonding. In this way, the entangled form of the nonwoven fabric is fixed by heat bonding, so that the form stability, dimensional stability, and mechanical strength are improved while maintaining the bulkiness, and the abrasion resistance, washing resistance, and durability are improved. Improvement can be achieved.
Therefore, the nonwoven fabric of the present invention does not deform due to frictional force, and there is no fluffing of the surface of the nonwoven fabric and no loss of fibers. Therefore, for example, when the nonwoven fabric of the present invention is used as a wiping material, stronger stains can be wiped off.

The heat treatment temperature is a temperature at which the heat-adhesive short fibers are melted or softened. When the melting point or softening point of the heat-adhesive component of the heat-adhesive short fibers is (Tm) ° C.,
Hot air of (m + 5) ° C. to (Tm + 25) ° C. is preferably blown. By adopting this temperature range, it is possible to obtain a nonwoven fabric in which only the heat-adhesive component is melted or softened and flexibility is maintained without affecting other constituent fibers and the like due to heat. If the temperature is lower than (Tm + 5) ° C., the desired heat bonding effect cannot be obtained because the heat bonding component does not sufficiently melt or soften. On the other hand, (Tm + 2
5) When the temperature exceeds 0 ° C., the heat-adhesive component melts and flows, and the nonwoven fabric is formed into a film, giving a feeling of coarse hardness. Also,
There is a possibility that even the ultrafine split short fibers may be melted, and the texture due to the ultrafine split short fibers is impaired, which is not preferable.

For the purpose of imparting flexibility to the nonwoven fabric of the present invention, a flexible processing machine using a camfighting machine manufactured by Uenoyama Kiko Co., Ltd. may be used.

[0031]

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 (° C.) of polymer: DS manufactured by PerkinElmer
Using a C-2 type differential scanning calorimeter, the heating rate was 20 ° C. /
The temperature giving the maximum value of the melting endothermic peak measured in minutes was defined as the melting point (° C.).

(2) Relative viscosity of polyester (a): A mixture of phenol and ethane tetrachloride was used as a solvent, and 0.5 g of a sample was dissolved in 100 cc of the solvent. .

(3) Relative viscosity of nylon 6 (b): 96
1 g of a sample was dissolved in 100 cc of 100% sulfuric acid, and determined by a conventional method at a temperature of 25 ° C.

(4) Melt index of polyethylene (hereinafter referred to as MI) (g / 10 minutes): ASTM D
It was measured by the method described in 1238 (E).

(5) Melt flow rate value of polypropylene (hereinafter referred to as MFR) (g / 10 minutes): AST
It was measured by the method described in MD1238 (L).

(6) Basis weight (g / m ² ): Five sample pieces each having a width of 10 cm and a length of 10 cm were prepared, and their weights were measured.
The average value of five sample pieces was defined as the basis weight (g / m ² ) of the nonwoven fabric.

(7) Tensile strength (kg / 5 cm width): JI
The maximum tensile strength was measured according to the strip method described in SL-1096. That is, width 5 cm, length 15 cm
Specimens of 10 were prepared, and a constant-speed elongation type tensile tester (Tensilon UTM-4-1-100 manufactured by Toyo Baldwin Co., Ltd.)
, The maximum tensile strength was measured under the conditions of a gripping interval of 10 cm and a tensile speed of 10 cm / min, and the average value of 10 test pieces was defined as the tensile strength (kg / 5 cm width) of the nonwoven fabric.

(8) Abrasion resistance (grade): A reciprocating friction test was performed 100 times using a Gakushin type friction tester, and a five-point evaluation was performed by visual evaluation. Those with no abrasion on the surface of the non-woven fabric and without fluff were rated as class 5, and those with severely abraded on the surface of the non-woven fabric were classified as class 1, and the grade between them was graded as grades 2 to 4.

(9) Dust wiping property: 5 g of sodium chloride, a special-grade reagent manufactured by Katayama Chemical Co., Ltd., was sprayed on a glass plate as dust, and the sodium chloride on the glass plate was wiped off with a non-woven fabric. The weight of sodium was measured. A nonwoven fabric exhibiting a wiping property of 70% or more was judged to have excellent wiping properties, and a nonwoven fabric exhibiting a wiping property of 75% or more was judged to have particularly excellent wiping properties.

EXAMPLE 1 Nylon 6 (melting point: 225.degree. C., relative viscosity: 2.degree. C.) having a fiber cross section shown in FIG.
65) and polypropylene (melting point 160 ° C, relative MFR2)
(8 g / 10 minutes). That is, as shown in FIG. 1, the composite ratio is set to 1: 1 in weight ratio from the split type two-component type composite spinneret in which the total number of divisions is 7, the melting temperature is 265 ° C., and the single hole discharge amount is 0.59.
Extruded at 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 2.8 using a known drawing machine,
It is crimped by an indentation type crimping device and cut to a fiber length of 38 mm. 2 denier (the fineness of the ultrafine split short fiber made of polypropylene is 1.0 denier, and the fine split short fiber made of nylon 6 is Short fibers having a fineness of 0.17 denier were obtained.

As the heat-adhesive short fiber, a conjugate spinneret capable of obtaining a core-sheath conjugate fiber was used, and polyethylene terephthalate (melting point: 259 ° C., relative viscosity: 1.3) was used as a core component.
8), polyethylene (melting point 128 ° C., MI
20 g / 10 min), and the composite ratio is calculated as follows: core component: sheath component =
It was extruded at 65:35 (weight ratio) at a melting temperature of 295 ° C. and a single hole discharge rate of 0.8 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 1100 m / min.
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 3.31 times using a known drawing machine, crimping is performed by a push-in type crimping device. This was applied and cut to a fiber length of 38 mm to obtain 2 denier heat-adhesive short fibers.

A nonwoven web having a basis weight of 80 g / m ² was prepared using a random card machine by mixing 70% by weight of split type bicomponent conjugate short fibers and 30% by weight of heat-adhesive short fibers.

Next, the nonwoven web was loaded on a 100-mesh metal mesh screen and subjected to high-pressure liquid flow treatment. The high-pressure liquid flow treatment uses a high-pressure liquid flow treatment device in which injection holes having a hole diameter of 0.1 mm are arranged at a hole interval of 0.6 mm, and a liquid flow pressure of 70 kg / cm ² G from a position 50 mm above the laminate. The treatment was performed under the conditions. Excessive moisture was removed from the entangled non-woven fabric and dried. Next, heat treatment was performed using a heat fusion processor (Lushiol Kyoto Kikai Co., Ltd.) under the conditions of a processing temperature of 140 ° C. and a processing time of 30 seconds to obtain a nonwoven fabric of the present invention.

Example 2 As a splittable bicomponent conjugate short fiber, polyethylene terephthalate (melting point: 258) having a fiber cross section shown in FIG.
° C, relative viscosity 1.38) and polypropylene (melting point 160
A nonwoven fabric of the present invention was obtained in the same manner as in Example 1, except that a splittable bicomponent conjugate short fiber consisting of C.C. and a relative MFR of 28 g / 10 minutes) was used. That is, as shown in FIG. 1, the weight ratio of the composite ratio is 1: 1 from the split type two-component type composite spinneret in which the total number of splits is 7, the melting temperature is 285 ° C., and the single hole discharge amount is 0.63 g. / Min. After cooling the spun yarn and applying a finishing oil, the take-up speed is 1000 m
/ Min was taken up as an undrawn yarn through a take-off roll. 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 3.0 using a known drawing machine, crimping is performed by a push-in type crimping device. It is applied and cut into a fiber length of 38 mm to produce a short fiber of 2 denier (the fineness of the ultrafine split short fiber made of polypropylene is 1.0 denier, and the fineness of the ultrafine split short fiber made of polyethylene terephthalate is 0.17 denier). Created.

Example 3 As a splittable bicomponent conjugate short fiber, polyethylene terephthalate (melting point: 258) having a fiber cross section shown in FIG.
° C, relative viscosity 1.38) and nylon 6 (melting point 225 ° C,
A nonwoven fabric of the present invention was obtained in the same manner as in Example 1, except that a splittable bicomponent conjugate short fiber having a relative viscosity of 2.65) was used. In other words, as shown in FIG. 1, the weight ratio of the composite ratio is 1: 1 from the split type two-component composite type spinneret in which the total number of divisions is 7, the melting temperature is 285 ° C., and the single hole discharge amount is 0.1.
Extruded at 65 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 aligned to form a tow,
After performing stretching at a stretching ratio of 3.1 times using a known stretching machine, crimping was performed using a press-in type crimping device, and 38 m was applied.
2 denier (fineness of ultrafine split short fibers made of nylon 6 is 1.0 denier, fineness of ultrafine split short fibers made of polyethylene terephthalate is 0.1
7 denier) short fiber was prepared.

Example 4 Nylon 6 (melting point: 225.degree. C., relative viscosity: 2.degree. C.) having a fiber cross section as shown in FIG.
65) and polypropylene (melting point 160 ° C, relative MFR2)
A nonwoven fabric of the present invention was obtained in the same manner as in Example 1, except that a splittable bicomponent conjugate short fiber (8 g / 10 min) was used. That is, as shown in FIG. 2, the weight ratio of the composite ratio is 1: 1 from the split type two-component type composite spinneret in which the total number of splits is 12, the melting temperature is 265 ° C., and the single hole discharge amount is 0.5.
Extruded at 6 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. Then
A plurality of the obtained undrawn yarns are drawn and aligned to form a tow, and after drawing at a draw ratio of 2.65 times using a known drawing machine, crimping is performed by a press-in type crimping device. 38mm
To produce a short fiber of 2 denier (the ultrafine split short fiber made of nylon 6 and the ultrafine split short fiber made of polypropylene have a fineness of 0.17 denier).

Example 5 As a splittable bicomponent conjugate short fiber, polyethylene terephthalate (melting point: 258) having a fiber cross section shown in FIG.
° C, relative viscosity 1.38) and polypropylene (melting point 160
A nonwoven fabric of the present invention was obtained in the same manner as in Example 1, except that a splittable bicomponent conjugate short fiber consisting of C.C. and a relative MFR of 28 g / 10 minutes) was used. That is, as shown in FIG. 2, the split ratio is 1: 1 by weight from a split type two-component type composite spinneret in which the total number of splits is 12, and the melting temperature is 285 ° C.
It was extruded at a single hole discharge rate of 0.6 g / min. After cooling the spun yarn and applying a finishing oil, the take-up speed is 1000 m
/ Min was taken up as an undrawn yarn through a take-off roll. Next, a plurality of the obtained undrawn yarns are drawn and aligned to form a tow, and after drawing at a draw ratio of 2.85 times using a known drawing machine, crimping is performed with a press-in type crimping device. The fiber was cut to a fiber length of 38 mm and cut into 2 deniers (the fineness of ultrafine split short fibers made of polyethylene terephthalate and ultrafine split short fibers made of polypropylene was 0.17.
Denier).

Example 6 As a splittable bicomponent conjugate short fiber, polyethylene terephthalate (melting point: 258) having a fiber cross section shown in FIG.
° C, relative viscosity 1.38) and nylon 6 (melting point 225 ° C,
A nonwoven fabric of the present invention was obtained in the same manner as in Example 1, except that a splittable bicomponent conjugate short fiber having a relative viscosity of 2.65) was used. That is, as shown in FIG. 2, the weight ratio of the composite ratio is 1: 1 from the split type two-component composite type spinneret in which the total number of divisions is 12, the melting temperature is 285 ° C., and the single hole discharge amount is 0.62 g. / Min. After the spun yarn was cooled and the finishing oil was applied, it was wound up as an undrawn yarn via a take-up roll having a take-up speed of 1000 m / min. Subsequently, a plurality of the obtained undrawn yarns are drawn and aligned to form a tow. After drawing is performed at a draw ratio of 2.95 times using a known drawing machine, crimping is performed by a push-in type crimping device. 2 denier (approximately 0.17 denier of ultrafine split short fiber made of polyethylene terephthalate and ultrafine split short fiber made of nylon 6)
Staple fibers were prepared.

Comparative Example 1 A nonwoven fabric of Comparative Example 1 was prepared in the same manner as in Example 1 except that the heat treatment was not performed.

Comparative Example 2 Comparative Example 2 was carried out in the same manner as in Example 1 except that the mixing ratio of the splittable bicomponent conjugate short fibers and the heat-adhesive short fibers was 30/70 (% by weight). Was prepared.

The physical properties of the obtained nonwoven fabrics of Examples 1 to 6 and Comparative Examples 1 and 2 were measured and are shown in Table 1.

[0052]

[Table 1]

The nonwoven fabrics of Examples 1 to 6 were subjected to heat treatment to fix the three-dimensional entangled form, and were excellent in mechanical strength, dimensional stability and abrasion resistance. It was excellent in usability and good in wiping. In addition, the surface touch of the non-woven fabric was soft because the ultrafine fibers were the main constituent fibers.
In particular, the nonwoven fabrics of Examples 4 to 6 in which the fineness after splitting the ultrafine split fibers were all 0.17 denier showed strong tendency in mechanical strength, abrasion resistance, and softness of surface touch. .

On the other hand, the non-woven fabric of Comparative Example 1 which was not subjected to the heat treatment was inferior in abrasion resistance and was not very suitable for use in a state where abrasion strength was required.

The nonwoven fabric of Comparative Example 2 mixed with 70% by weight of adhesive short fibers had good abrasion resistance, but the nonwoven fabric surface was hard and uncomfortable. And the texture of the ultrafine fibers was impaired.

[0056]

According to the nonwoven fabric of the present invention, the constituent fibers are entangled with each other and integrated as a whole. When the fibers are entangled by the high-pressure liquid flow treatment, ultrafine split short fibers having a small bending moment are developed, so that the degree of entanglement between the fibers is improved, and a nonwoven fabric that is densely entangled and integrated as a whole is obtained. In addition, since ultra-fine split short fibers are the main constituent fibers,
It has a soft surface touch.

Furthermore, since the nonwoven fabric of the present invention has a three-dimensionally entangled form fixed by the heat-adhesive fiber, it does not deform due to external force, that is, has excellent dimensional stability and high mechanical strength. It has become. Then, even when a surface frictional force is applied, fluffing and detachment of the fiber hardly occur, and the nonwoven fabric has excellent abrasion resistance.

Since the nonwoven fabric of the present invention has the above properties, it can be wiped dry and wet for a wide range of uses such as glass, mirrors, glasses, furniture, floors, car and makeup puffs, towels and towels. As a cleaning material for
Further, it can be effectively used as an industrial or household filter medium or filter medium. Furthermore, it can be suitably used in various fields such as medical materials, sanitary materials, clothing, and living materials.

[Brief description of the drawings]

FIG. 1 is a schematic diagram of one embodiment of a cross section of a splittable bicomponent conjugate short fiber used in the present invention.

FIG. 2 is a schematic diagram showing one embodiment of a cross section of a splittable bicomponent conjugate short fiber used in the present invention.

FIG. 3 is a schematic diagram showing one embodiment of a cross section of a splittable bicomponent conjugate short fiber used in the present invention.

FIG. 4 is a schematic diagram of one embodiment of a cross section of a splittable bicomponent conjugate short fiber used in the present invention.

Claims (3)

[Claims] 1. A nonwoven fabric comprising ultrafine split short fibers developed by splitting splittable bicomponent conjugate short fibers made of mutually incompatible fiber-forming polymers, and heat-adhesive short fibers. A nonwoven fabric, wherein fibers are three-dimensionally entangled and the entangled form is fixed by heat fusion of the heat-adhesive short fibers. 2. The fineness of an ultrafine split short fiber which is at least developed by splitting a splittable bicomponent conjugate short fiber has a fineness of 0.1%.
The nonwoven fabric according to claim 1, wherein the nonwoven fabric has a denier of 5 deniers or less. 3. A nonwoven web obtained by mixing 90 to 60% by weight of a splittable bicomponent conjugate short fiber composed of mutually incompatible fiber-forming polymers and 10 to 40% by weight of a heat-adhesive short fiber. Then, the nonwoven web is placed on a porous support material and subjected to a high-pressure liquid flow treatment, and the composite short fibers are split to express ultrafine split short fibers and the constituent fibers are three-dimensionally entangled with each other. A method for producing a nonwoven fabric, comprising: performing heat treatment at a temperature at which the heat-adhesive short fibers are melted or softened, and heat-fusing the heat-adhesive short fibers to fix the entangled form.