CN100363541C

CN100363541C - Nanofiber aggregate, polymer alloy fiber, hybrid fiber, fibrous structures, and processes for production of them

Info

Publication number: CN100363541C
Application number: CNB2003801050309A
Authority: CN
Inventors: 越智隆志; 木代明; 野中修一
Original assignee: Toray Industries Inc
Current assignee: Toray Industries Inc
Priority date: 2002-10-23
Filing date: 2003-10-22
Publication date: 2008-01-23
Anticipated expiration: 2023-10-22
Also published as: CN1720358A

Abstract

The invention provides an aggregate of nanofibers which is not limited in shape or material polymer, is widely applicable and developable, and has a small dispersion of single fiber fineness, and a process for the production thereof. The invention relates to an aggregate of nanofibers which have a number-average single fiber fineness of 1 x 10<-7> to 2 x 10<-4> dtex and a proportion of single fibers having single fiber fineness ranging from 1 x 10<-7> to 2 x 10<-4> dtex of 60 % or above and which are made of a thermoplastic polymer.

Description

Nanofiber aggregate, polymer alloy fiber, hybrid fiber, fiber structure, and methods for producing same

Technical Field

The present invention relates to a nanofiber assembly. The present invention also relates to a polymer alloy fiber that becomes a precursor of the nanofiber aggregate. The present invention also relates to a hybrid fiber and a fiber structure containing the nanofiber aggregate. The present invention also relates to a method for producing these.

Background

Polyester typified by polyethylene terephthalate (hereinafter abbreviated as PET) and polybutylene terephthalate (hereinafter abbreviated as PBT), or polycondensation polymers such as polyamide typified by nylon 6 (hereinafter abbreviated as N6) and nylon 66 (hereinafter abbreviated as N66) have been conventionally used as clothing and industrial materials because they have appropriate mechanical properties and heat resistance. On the other hand, addition polymerization type polymers represented by polyethylene (hereinafter abbreviated as PE) and polypropylene (hereinafter abbreviated as PP) are mainly used as industrial raw material fibers because they have appropriate mechanical properties and chemical resistance and are lightweight.

In particular, polyester fibers and polyamide fibers are sometimes used as clothing, and therefore, not only the polymer is modified, but also the cross-sectional shape of the fibers and the performance of the fibers is improved by the ultrafine fibers. As one of these studies, a new generation of new textile products, which produces artificial leather having a suede-like quality by using super-filament of polyester produced by sea-island composite spinning, was developed. In addition, the ultrafine filament is suitable for general clothing, and can also be used for producing clothing with excellent soft hand feeling which can not be obtained by the conventional fiber absolutely. In addition, since the ultra-fine yarn can be used not only as clothing but also as life data and industrial data such as a wipe, the conventional synthetic fiber has gained a steady position in the world.

In particular, recently, the polishing cloth for the surface of a computer hard disk described in Japanese patent application laid-open No. 2001-1252 and the cell-adsorbing material described in Japanese patent application laid-open No. 2002-172163 have been widely used as medical materials.

Therefore, in order to obtain higher levels of artificial leather and high-quality clothing, development of finer fibers is desired. In order to increase the capacity of the hard disk and further increase the recording density of the hard disk, it is necessary to further smooth the surface of the hard disk having an average surface roughness of 1nm or more to an average surface roughness of 0.5nm or less. Therefore, as a fiber of a polishing cloth for polishing the surface of a hard disk, it is desired to obtain a further ultrafine nanofiber.

In addition, even for medical use, nanofibers having the same size as that of a biological constituent fiber are desired for the purpose of improving affinity with cells.

However, with the current sea-island composite spinning technology, the single fiber fineness is limited to 0.04 dtex (equivalent to 2 μm in diameter), and does not reach a level sufficient for satisfying nanofibers. Further, a method for producing a super-fine yarn using a polymer blend fiber is described in Japanese unexamined patent publication Hei 3-113082 and Japanese unexamined patent publication Hei 6-272114, but the fineness of the single fiber obtained here is 0.001 dtex (equivalent to 0.4 μm in diameter), and the level required for a nanofiber is not yet sufficiently satisfied.

Further, a method for producing a super fine yarn from a polymer blend fiber obtained by a static mixer is disclosed in USP4,686,074. However, even the ultra-fine filaments produced by this technique do not reach a level sufficient to satisfy the nanofibers.

Therefore, as a technique for making fibers ultra-fine, a so-called electrospinning technique (ェレクトロスピニング) has attracted considerable attention in recent years. In the electrospinning, a polymer is dissolved in an electrolyte solution, and when the polymer solution is extruded from a nozzle, a high voltage of several thousands to 3 ten thousand volts is applied to the polymer solution to jet the polymer solution at a high speed, and then the polymer solution is expanded to be extremely fine by bending the jet (れ zig- り). When this technique is used, the single fiber fineness is 10 ^-5 On the dtex scale (single fiber diameter corresponding to several tens of nm), the fineness is 1/100 or less and the diameter is 1/10 or less, as compared with the conventional polymer compounding technique. Many of the polymers to be used are biopolymers such as collagen and water-soluble polymers, but there are also examples in which a thermoplastic polymer is dissolved in an organic solvent and is subjected to electrospinning. However, as described in Polymer, vol.40, 4585 (1999), the "twines" as the super fine filament portions are mostly "slubby yarns" (straight yarns) passing through the Polymer smooth portionsDiameter 0.5 μm), and large variation in single fiber fineness when observed as a super fine aggregate. Therefore, studies have been conducted to suppress the formation of "slubby yarn" and to make the fiber diameter uniform, but such variation in fineness is still large (Polymer vol.43, 4403 (2002)). Further, the shape of the fiber aggregate obtained by electrospinning is limited to a nonwoven fabric, and many of the obtained fiber aggregates are not crystallized in an oriented manner, and only a product having a lower strength than a normal fiber product is obtained, so that the application prospect is greatly restricted. In addition, the thickness of the fiber product obtained by the electronic spinning reaches 100cm ² On the other hand, the productivity reaches several grams per hour to the maximum, and the productivity is very low as compared with the usual melt spinning. In addition, when a high voltage is used, there are problems such as suspension of the organic solvent and the ultrafine filament in the air.

Thus, as a special method for producing nanofibers, it is known that Sciencevol.2113 (1999) is usedThe mesoporous silica is used to carry polymerization catalyst, and the PE polymerization is carried out to obtain the product with diameter of 30-50 nm (equivalent to 5X 10) ^-6 ～2×10 ^-5 Dtex) of PE nanofiber fragments. However, with this method only a cotton-like mass of nanofibers is obtained, from which fibers cannot be drawn. The polymers used are limited to addition polymerization type PE, and polycondensation type polymers such as polyesters and polyamides, and dehydration is necessary in the polymerization process, and therefore, the operation is difficult in principle. Therefore, the application prospect of the nano-fiber obtained by the method is greatly restricted.

Disclosure of Invention

The present invention provides a nanofiber polymer which is widely applicable without being restricted in shape and polymer and has small single fiber fineness variation, and a method for producing the same.

The present invention is constituted as follows.

(1) An aggregate of nanofibers having a number average single fiber fineness of 1X 10 ^-7 ～2×10 ^-4 Single fiber fineness of single fiber with decitex of 60% or more is 1 × 10 ^-7 ～2×10 ^-4 In the dtex range and consisting of thermoplastic polymers.

(2) The nanofiber assembly described in (1) above is in the form of a long fiber and/or a spun yarn.

(3) The nanofiber assembly as described in the above (1) or (2), wherein the number average single fiber fineness is 1X 10 ^-7 ～1×10 ^-4 Single fiber fineness of single fiber with decitex of 60% or more is 1 × 10 ^-7 ～1×10 ^-4 The range of decitex.

(4) The nanofiber assembly according to any one of (1) to (3) above, wherein the single fibers constituting the nanofiber polymer have a fineness ratio of 50% or more, and have a variation in single fiber diameter of 30nm in width.

(5) The nanofiber assembly according to any one of (1) to (4) above, wherein the thermoplastic polymer is a condensation polymer.

(6) The nanofiber assembly according to any one of (1) to (5) above, wherein the thermoplastic polymer has a melting point of 160 ℃ or more.

(7) The nanofiber assembly according to any one of (1) to (6) above, wherein the thermoplastic polymer is selected from the group consisting of polyesters, polyamides, and polyolefins.

(8) The nanofiber assembly according to any one of (1) to (7) above, wherein the strength is 1cN/dtex or more.

(9) The nanofiber assembly according to any one of (1) to (8) above, wherein the moisture absorption rate is 4% or more.

(10) The nanofiber assembly according to any one of (1) to (9) above, wherein the moisture absorption expansion coefficient in the filament length direction is 5% or more.

(11) The nanofiber assembly according to any one of (1) to (10) above, which contains a functional drug.

(12) A fibrous structure comprising the nanofiber assembly according to any one of (1) to (11) above.

(13) The fiber structure according to item (12) above, wherein the fiber has a basis weight of 20 to 2000g/m ² 。

(14) The fiber structure according to (12) or (13) above, wherein a hollow portion of the hollow fiber of the nanofiber aggregate is encapsulated.

(15) The fiber structure according to item (14) above, wherein the hollow fiber has a large number of pores having a diameter of 100nm or less in the longitudinal direction.

(16) The fiber structure according to any one of (12) to (15) above, wherein the functional agent is contained.

(17) The fibrous structure according to any one of (12) to (16) above, wherein the fibrous structure is selected from the group consisting of silk, cotton, packaging materials, woven fabrics, felts, nonwoven fabrics, artificial leathers, and sheets.

(18) The fiber structure according to item (17) above, wherein the fiber structure is a laminated nonwoven fabric in which a nonwoven fabric containing a nanofiber aggregate and nonwoven fabrics other than the nonwoven fabric are laminated.

(19) The fiber structure according to any one of the above (12) to (18), wherein the fiber structure is a fiber product selected from clothing, clothing materials, interior products for vehicles, living materials, environmental/industrial material products, IT parts, and medical products.

(20) A liquid dispersion of the nanofiber assembly as set forth in any one of (1) to (11) above.

(21) A polymer alloy fiber having a sea-island structure composed of 2 or more organic polymers having different solubilities, wherein the island component is composed of a hardly soluble polymer and the sea component is composed of a easily soluble polymer, the number average diameter of the island region is 1 to 150nm, the number average diameter of the island region having an area ratio of 60% or more is 1 to 150nm, and the island component is dispersed in a stripe shape.

(22) The polymer alloy fiber according to item (21), wherein the island regions have a number average diameter of 1 to 100nm, and the island regions having an area ratio of 60% or more have a number average diameter of 1 to 100nm.

(23) The polymer alloy fiber according to the above (21) or (22), wherein the difference in diameter between island regions in the island regions contained in the polymer alloy fiber, the island regions having an area ratio of 60% or more, is within a range of 30 nm.

(24) The polymer alloy fiber according to any one of (21) to (23) above, wherein the content of the island component is 10 to 30% by weight based on the entire fiber.

(25) The polymer alloy fiber according to any one of (21) to (24) above, wherein the sea component is composed of a polymer that is easily soluble in an aqueous alkali solution or hot water.

(26) The polymer alloy fiber according to any one of (21) to (25) above, wherein the island component has a melting point of 160 ℃ or more.

(27) A polymer alloy fiber which is a composite fiber obtained by bonding the polymer alloy according to any one of the above (21) to (26) and another polymer.

(28) The polymer alloy fiber according to any one of (21) to (27) above, wherein a CR value as an index of crimp characteristics is 20% or more, or a number of crimps is 5/25 mm or more.

(29) The polymer alloy fiber according to any one of (21) to (28), wherein the Wursted spots are 5% or less.

(30) The polymer alloy fiber according to any one of (21) to (29), wherein the strength is 1.0cN/dtex.

(31) A fiber structure comprising the polymer alloy fiber according to any one of the above (21) to (30).

(32) The fibrous structure according to item (31) above, wherein the fibrous structure is selected from the group consisting of silk, cotton, a wrapper, a woven fabric, a knitted fabric, a felt, a nonwoven fabric, an artificial leather, and a sheet.

(33) The fiber structure according to the above (31) or (32), wherein the fiber structure contains a polymer alloy fiber and other fibers.

(34) The fiber structure according to any one of the above (31) to (33), wherein the fiber structure is selected from the group consisting of clothing, clothing materials, interior products for vehicles, living materials, environmental/industrial material products, IT components, and medical products.

(35) A process for producing a polymer alloy fiber, which comprises melt-spinning a polymer alloy obtained by melt-mixing a poorly soluble polymer and a readily soluble polymer, wherein the process satisfies the following conditions (1) to (3):

(1) Separately metering a sparingly soluble polymer and a readily soluble polymer, and separately supplying the metered amounts to a kneading apparatus for melt-mixing;

(2) The content of the insoluble polymer in the polymer alloy is in the range of 10 to 50 wt%;

(3) The melt viscosity of the easily soluble polymer is 100 pas or less, or the melting point of the easily soluble polymer is in the range of-20 to +20 ℃ of the melting point of the hardly soluble polymer.

(36) The method for producing a polymer alloy fiber according to item (35) above, wherein the melt-mixing is performed using a twin-screw extruder, and the length of the kneading section of the twin-screw extruder is 20 to 40% of the effective length of the screw.

(37) The method for producing a polymer alloy fiber according to item (35) above, wherein the melt-mixing is performed by a static mixer, and the number of divisions of the static mixer is 100 ten thousand or more, or 100 ten thousand or more.

(38) The process for producing a polymer alloy fiber according to any one of (35) to (37), wherein the shear stress between the wall of the nozzle hole and the polymer in the melt spinning is 0.2MPa or less or 0.2MPa or less.

(39) A polymer alloy particle having a sea-island structure composed of 2 kinds of organic polymers having different solubilities, wherein the island component is composed of a poorly soluble polymer and the sea component is composed of a highly soluble polymer, and the melt viscosity of the highly soluble polymer is 100 pas or less or the melting point of the highly soluble polymer is in the range of-20 to +20 ℃ as the melting point of the poorly soluble polymer.

(40) An organic/inorganic hybrid fiber comprising 5 to 95 wt% of the nanofiber aggregate according to any one of (1) to (11) above, wherein at least a part of the inorganic substance is present in the inside of the nanofiber aggregate.

(41) A fibrous structure comprising the organic/inorganic hybrid fiber according to (40) above.

(42) The method for producing an organic/inorganic hybrid fiber according to item (40) above, wherein the nanofiber aggregate is impregnated with an inorganic monomer, and then the inorganic monomer is polymerized.

(43) The method for producing a fiber structure according to item (41) above, wherein the fiber structure comprising the nanofiber aggregate is impregnated with an inorganic monomer and then the inorganic monomer is polymerized.

(44) A method for producing a hybrid fiber, comprising impregnating the nanofiber assembly of any one of (1) to (11) above with an organic monomer and then polymerizing the organic monomer.

(45) A method for producing a fibrous structure, wherein an organic monomer is impregnated in the fibrous structure according to any one of the above (12) to (19) and then polymerized.

(46) A porous fiber, wherein 90% by weight or more of the composition is composed of an inorganic substance, a large number of pores are present in the longitudinal direction, and the number average pore diameter in the cross section in the minor axis direction is 1 to 100nm.

(47) A fibrous structure comprising the porous fiber according to (46) above.

(48) A method for producing a porous fiber, wherein the porous fiber described in (46) above is obtained by impregnating a nanofiber aggregate with an inorganic monomer, polymerizing the inorganic monomer, and removing the nanofibers from the obtained organic/inorganic hybrid fiber.

(49) A method for producing a fiber structure, wherein nanofibers are removed from a structure comprising organic/inorganic hybrid fibers obtained by impregnating a fiber structure comprising a nanofiber aggregate with an inorganic monomer and then polymerizing the inorganic monomer, thereby obtaining the fiber structure described in (47) above.

(50) A process for producing a nonwoven fabric, which comprises cutting the polymer alloy fiber according to any one of the above (21) to (30) into a fiber length of 10mm, eluting the easily soluble polymer, and then papermaking without preliminary drying.

(51) A process for producing a nonwoven fabric, which comprises forming a nonwoven fabric or a felt comprising the polymer alloy fiber according to any one of the above (21) to (30), bonding the nonwoven fabric or the felt to a substrate comprising a hardly soluble polymer, and then eluting the easily soluble polymer.

Drawings

Fig. 1 is a TEM photograph showing a cross section of an aggregate fiber of the nylon nanofibers of example 1.

FIG. 2 is a TEM photograph showing the cross-section of the polymer alloy fiber of example 1.

FIG. 3 is an SEM photograph showing a cross section of an aggregate fiber of the nylon nanofibers of example 1.

Fig. 4 is an optical microscope photograph showing a fiber side surface state of an aggregate of nylon nanofibers of example 1.

Fig. 5 is a graph showing the variation in the single fiber fineness of the nanofibers of example 1.

Fig. 6 is a graph showing the variation in single fiber fineness of the nanofibers of example 1.

FIG. 7 is a graph showing the variation in the single fiber fineness of the nanofibers of comparative example 4.

FIG. 8 is a graph showing the variation in the single fiber fineness of the ultrafine filament of comparative example 4.

FIG. 9 is a graph showing the variation in the single fiber fineness of the ultrafine filament of comparative example 5.

FIG. 10 is a graph showing the variation in the single fiber fineness of the ultrafine filament of comparative example 5.

FIG. 11 is a graph showing the reversible water-swelling property of example 1.

FIG. 12 is a drawing showing a spinning machine.

FIG. 13 is a view showing a nozzle.

Fig. 14 is a drawing machine.

FIG. 15 is a drawing showing a spinning machine.

FIG. 16 is a drawing showing a spinning machine.

FIG. 17 is a drawing showing a spinning machine.

FIG. 18 is a view showing a rotary head spinning device

FIG. 19 is a view showing ammonia elimination properties.

FIG. 20 is a diagram showing the property of eliminating formaldehyde odor.

FIG. 21 is a drawing showing a toluene odor eliminating property.

FIG. 22 is a graph showing the odor elimination of hydrogen sulfide.

Detailed Description

Preferred thermoplastic polymers used in the nanofiber aggregate of the present invention include polyesters, polyamides, polyolefins, polyphenylene sulfide, and the like. Among them, polycondensation polymers such as polyesters and polyamides are preferred in many cases to have a high melting point. When the melting point of the polymer is 160 ℃ or higher, the heat resistance of the nanofiber is good, and it is preferable. For example, polylactic acid (hereinafter abbreviated as PLA) is 170 ℃, PET is 255 ℃, and N6 is 220 ℃. The polymer may further contain additives such as particles, flame retardants, and antistatic agents. The copolymer may be copolymerized with other components within a range not impairing the properties of the polymer.

The nanofibers in the present invention are fibers having a single fiber diameter of 1 to 250nm, and the mass of the fibers collected together is referred to as a nanofiber aggregate.

In the present invention, the average value and the variation of the single fiber fineness in the nanofiber aggregate are important. The cross section of the nanofiber aggregate was observed with a Transmission Electron Microscope (TEM), and 300 or more single fibers were arbitrarily drawn out in the same cross section to measure the diameter of the single fiber. An example of a cross section of a nanofiber of the present invention is shown in fig. 1. The average value and variation of the single fiber fineness in the nanofiber aggregate were determined by measuring the total single fiber diameter of 1500 or more fibers at least at 5 positions or more. These measurement positions are preferably separated from each other by 10m or more as the length of the nanofiber aggregate from the viewpoint of ensuring uniformity of the fiber product obtained from the nanofiber aggregate.

The average single fiber fineness was determined by the following method. That is, the fineness was calculated from the measured diameter of the single fiber and the density of the polymer constituting the single fiber, and a simple average value of these was obtained. This is referred to as "the number average single fiber fineness" in the present invention. Further, density values used in the calculation were calculated using each polymerThe values generally used. In the present invention, the fineness of the number-average single fiber is 1X 10 ^-7 ～2×10 ^-4 Dtex (corresponding to a single fiber diameter of 1 to 150 nm) is important. This is because the size of the super-filament obtained by the sea-island composite spinning is as small as 1/100 to 1/100,000, and a cloth for clothing having a texture completely different from that of the original super-filament can be obtained. Further, when used as a polishing cloth for a hard disk, the smoothness of the hard disk is greatly improved as compared with the conventional one. The number-average single fiber fineness is preferably 1X 10 ^-7 ～1 ×10 ^-4 Dtex (corresponding to a single fiber diameter of 1 to 100 nm), more preferably 0.8X 10 ^-5 ～6×10 ^-5 Dtex (single fiber diameter equivalent to 30-80 nm).

Further, the variation in the single fiber fineness of the nanofibers was evaluated by the following method. That is, dt for the single fiber fineness of each single fiber _i The total titer (dt) is shown as the sum ₁ +dt ₂ +dt ₃ +…dt _n ). The fineness ratio of the single fiber fineness is determined by dividing the product of the nanofiber fineness and the frequency (number) of the single fiber fineness by the total fineness. The fineness ratio corresponds to the weight ratio (volume fraction) of each single fiber fineness component to the whole (nanofiber aggregate), and a single fiber fineness component having a large value largely affects the properties of the nanofiber aggregate. In the present invention, the single fibers having a fineness ratio of 60% or more are at least 1X 10 ^-7 ～2×10 ^-4 The range of dtex (single fiber diameter equivalent to 1 to 150 nm) is important. That is, it means when it is larger than 2X 10 ^-4 The presence of nanofibers is close to zero in decitex (single fiber diameter corresponds to 150 nm).

Further, the above-mentioned USP4,686,074 discloses a method for producing a super fine yarn by mixing a fiber with a polymer obtained by a static mixer. It is described that the theoretical single fiber fineness obtained by calculation from the number of divisions of the static mixer is 1X 10 ^-4 When the fiber is measured in dtex (diameter corresponding to about 100 nm), nanofibers can be obtained, but the single fiber fineness of the obtained ultrafine fiber is measured to be 1X 10 ^-4 dtex-1X 10 ^-2 When the diameter is dtex (about 1 μm), nanofibers having uniform single fiber diameter cannot be obtained. This is considered to be due to the fact that the island polymers are united in the polymer hybrid fiber and thus the island polymers are not uniformly dispersed in a nano size. Therefore, the super-fine yarn obtained by this technique has a large variation in single fiber fineness. When the variation in the fineness of the single fibers is large, the performance of the product is strongly affected by the thick single fibers, and therefore, the advantages of the ultra-fine filaments cannot be sufficiently exhibited. In addition, the quality is stable due to the variation of single fiber finenessQualitative and the like also have problems. In addition, when the polishing cloth for a hard disk is used, since the fineness variation is large, the abrasive grains cannot be uniformly supported on the polishing cloth, and as a result, the smoothness of the surface of the hard disk is rather lowered.

In contrast, the nanofiber aggregate of the present invention has a small variation in single fiber fineness, can sufficiently exhibit the function of nanofibers, and has good product quality stability. In addition, when used as the surface polishing cloth for hard disks, since the fineness variation is small, even the nanofibers can uniformly carry abrasive grains, and as a result, the polishing cloth for hard disks has a small fineness variation and can be used as a polishing pad for hard disksThe smoothness of the surface of the hard disk is dramatically increased. Preferably, the single fiber having a fineness ratio of 60% or more is at 1X 10 ^-7 ～1×10 ^-4 Dtex (single fiber diameter equivalent to 1 to 100 nm), more preferably 1X 10 ^-7 ～6×10 ^-5 Decitex (single fiber diameter equivalent to 1-80 nm). More preferably, the single fibers have a fineness ratio of 75% or more of 1X 10 ^-7 ～6×10 ^-5 Dtex (single fiber diameter equivalent to 1 to 80 nm) range.

Further, another index of the fineness deviation is a fineness ratio of a single fiber having a difference in single fiber diameter into a width of 30 nm. When counting the frequency of each single fiber diameter and dividing the single fiber diameter into 30nm wide sections, the total value of the fineness ratios of the 30nm wide single fibers having the highest frequency is the fineness ratio of the single fiber having a single fiber diameter difference of 30nm wide. This means that the deviation is concentrated in the vicinity of the central fineness, and the higher the fineness ratio, the smaller the deviation. In the present invention, it is preferable that the fineness ratio of the single fibers having a difference in diameter between the single fibers entering a width of 30nm is 50% or more. More preferably 70% or more.

In the present invention, it is preferable that the nanofiber aggregate is formed into a long fiber shape and/or a spun yarn shape. The long fiber shape and/or the spun yarn shape referred to herein means the following state. That is, like a composite yarn and a woven yarn, an assembly in which a plurality of nanofibers are oriented in 1-element is continuous in a finite length. An example of a side photograph of the nanofiber aggregate of the present invention is shown in fig. 3. On the other hand, the nonwoven fabric obtained by electrospinning is completely different in morphology in that all nanofibers are unoriented 2-element structure aggregates. The invention relates to a 1-element oriented nanofiber aggregate, which is very novel. The length of the nanofiber aggregate of the present invention is preferably several meters or more as long as that of a conventional multifilament. Therefore, the woven fabric and the knitted fabric can be formed into various fiber structures such as a short fiber, a nonwoven fabric, and a thermal compression molded body.

Further, the nanofiber aggregate of the present invention is characterized in that the single fiber diameter is 1/10 to 1/100 or less of that of the original ultrafine filament, and therefore, the specific surface area is dramatically increased. Thus, the characteristic properties of nanofibers not seen with conventional ultramicrofilaments are shown.

For example, the adsorption property is greatly improved. In fact, the adsorption of water vapor, i.e., the moisture absorption, of the polyamide nanofiber aggregate of the present invention is about 2% in the moisture absorption rate of the polyamide ultrafine filament compared to the polyamide ultrafine filament of the present invention, and the polyamide nanofiber aggregate of the present invention is up to 6%. Moisture absorption is a very important characteristic from the viewpoint of comfort when used as clothing, and in the present invention, a moisture absorption rate of 4% or more is preferable. The method for measuring the moisture absorption rate (. DELTA.MR) is described below.

Further, the fiber has excellent adsorption to malodorous substances such as acetic acid, ammonia, and hydrogen sulfide, and has an excellent deodorizing rate and deodorizing speed as compared with conventional polyamide fibers. In addition, besides single malodorous substances, formaldehyde, environmental hormones, heavy metal compounds and other harmful substances which are pathogenic substances of home decoration diseases can be adsorbed.

In addition, since the nanofiber aggregate of the present invention generates many gaps of about several nm to several hundred nm between single fibers of nanofibers, it may exhibit a specific property like a super-porous material.

For example, the liquid absorbency can be greatly improved. In fact, the water absorption of the polyamide nanofiber monomer of the present invention is about 26% in the normal polyamide fiber, compared with the water absorption of the normal polyamide fiber, and the water absorption of the polyamide nanofiber of the present invention is 83% or more, which is 3 times or more. In addition, while the expansion ratio in the filament length direction by water absorption is about 3% by using a general polyamide ultrafine filament, the expansion ratio of the polyamide nanofiber aggregate of the present invention is 7%. However, the water-absorbing swelling, when dried, returns to the original length and thus exhibits a reversible dimensional change. The fiber fabric having such a reversible water absorption/drying expansibility in the filament length direction is an important characteristic in view of the soil release property of the fabric, and it is preferable in the present invention that the fiber fabric has 5% or more. The term "detergency" as used herein means a property that contaminants are easily removed by washing. Therefore, the water-absorbing nanofiber aggregate absorbs water in the filament length direction and swells, so that gaps between fibers (weaving holes and knitting holes) in the woven fabric and the knitted fabric are enlarged, and therefore, the contaminants attached between the fibers are easily removed.

Further, when the nanofiber aggregate of the present invention is used as clothing, a fiber product having excellent quality and texture such as soft feeling like silk and dry feeling like rayon can be obtained. Further, by opening the nanofibers from the nanofiber aggregate by polishing or the like, it is possible to obtain a textile product excellent in super touch and wet touch such as human skin, which could not be expected in the past.

Further, the nanofiber aggregate of the present invention is preferably one which is oriented to crystallize. The degree of directional crystallization can be evaluated by wide-angle X-ray diffraction (WAXD). Here, when the crystallization degree by Rouland method is 25% or more, the thermal shrinkage of the fiber is reduced and the dimensional stability is improved, which is preferable. When the degree of crystal orientation is 0.8 or more, the molecular orientation is improved, and the strength of the yarn is preferably improved.

It is preferable that the strength of the nanofiber aggregate of the present invention is 1cN/dtex or more because the mechanical properties of the fiber product are improved. The nanofiber aggregate strength is more preferably 2cN/dtex or more. The thermal shrinkage of the nanofiber aggregate of the present invention can be adjusted depending on the application, but when used as clothing, it is preferable that the dry heat shrinkage at 140 ℃ is 10% or less.

Various fiber structures can be formed by using the nanofiber assembly of the present invention. The fiber structure is generally referred to as a 1-element, 2-element or 3-element fiber structure. Examples of the 1-fiber structure include long fibers, short fibers, spun yarns, and rod-like bodies (rod), examples of the 2-fiber structure include fabrics, sheets, and the like such as woven fabrics, knitted fabrics, and nonwoven fabrics, and examples of the 3-fiber structure include clothing, mesh, thermoformed articles, and cotton. Also means components and end products obtained by combining these with other materials, etc.

In addition, when the weight fraction of the nanofiber aggregate in the structure of the present invention is 10% or more, the excellent performance of the nanofibers such as adsorption property can be sufficiently exhibited, which is preferable. The weight fraction of the nanofiber aggregate is more preferably 50% or more.

Especially when the product is required to have form stability and durability to washing, the fiber mesh weight is 20-2000 g/m ² This is preferable. Here, the basis weight of the fiber is a value obtained by dividing the weight of the fiber by the area of the fiber portion. Smaller and lighter, loose structure, and poor dimensional stability and durability. The larger the eye payment is, the heavier the eye payment is, the firm structure is, and the dimensional stability and the durability are improved. Particularly, in the present invention, since the use of nanofibers tends to deteriorate the dimensional stability and durability, it is preferable to set the fiber to 20g/m ² Or more, to ensure dimensional stability and durability. Further, the basis weight is 2000g/m ² Or less, a certain degree of lightness can be ensured. The optimum value of the basis weight varies depending on the type of product, and is as light as 25 to 40g/m as a nonwoven fabric for packaging ² About 50 to 200g/m as a clothing material ² About 100 to 250g/m as a curtain or the like ² About 100 to 350g/m as a car pad ² About 1000 to 1500g/m for heavy articles such as blankets ² The left and right are preferable. Especially for the washed products, 50g/m for preventing washing deformation during washing ² Or more thereof is preferable.

The fibrous structure comprising the nanofiber aggregate of the present invention can be produced into intermediate products such as silk, cotton (cotton), packaging materials, woven fabrics, knitted fabrics, felts, nonwoven fabrics, artificial leathers, and sheets. Further, the fiber-reinforced resin composition is very suitable for use as articles for daily use such as clothing, clothing materials, interior products for vehicles, and articles for daily use such as living materials (wipes, cosmetics, health products, toys, etc.), articles for environmental and industrial materials (building materials, polishing cloths, filter cloths, harmful substance-removing products, etc.), IT parts (sensor parts, battery parts, robot parts, etc.), and medical products (blood filters, extracorporeal circulation columns, stents, wound dressings, artificial blood vessels, sustained-release drugs, etc.).

Most of the above applications, nanofiber nonwoven fabrics obtained by electrospinning cannot be used in a wide range of fields because of insufficient strength and form stability, insufficient size (width), and the like, but they have been made possible by the nanofiber assembly of the present invention. For example, since the strength of the product is required for clothing, interior materials, vehicle interior materials, abrasive cloth, filter cloth, various IT parts, and the like, the nanofiber assembly having excellent yarn strength of the present invention can be used.

In addition, in most of the above applications, the original nanofiber absorbability and liquid absorbability are insufficient, and the polishing property and the wiping property are insufficient due to the problem of the absolute size, and the performances of some applications are not satisfactory.

Therefore, the nanofiber aggregate of the present invention, and various products derived therefrom, can solve the problems of the conventional fine fibers and electronic textile nonwoven fabrics.

The nanofiber assembly of the present invention is preferably used because the hollow portion of the hollow fiber is an encapsulated structure, which improves the form stability of the fiber and the color development of the dyed product. Excessive aggregation of nanofibers is prevented, and deterioration of the excellent properties inherent to nanofibers can be suppressed. In addition, even when the fibers are bent or pressure is applied from the side of the fibers, the nanofibers in the hollow portion function as a cushion, and exhibit a soft texture like cotton candy, and thus, the encapsulated structure is very useful for clothing applications, interior decoration applications, vehicle interior decoration applications, clothing material applications, living material applications, and the like.

Further, as the hollow filament polymer used in the capsule, specifically, when the density of the hollow filament is 1.25g/cm ³ Or less, the nanofiber absorbability and the liquid water absorbability in the hollow part can be sufficiently exhibited, and it is preferable. This is because the hollow filaments have a low density, i.e., a wide molecular chain interval, and are easily permeable to various molecules. As a preferred example of the polymer, PLA (1.25 g/cm) may be mentioned ³ )、N6(1.14g/cm ³ )、 N66(1.14g/cm ³ )、PP(0.94g/cm ³ )、PE(0.95g/cm ³ ) Polymethylpentene (PMP, 0.84 g/cm) ³ ) And so on. The polymer density is in parentheses. The density of the hollow filaments is preferably 1.20g/cm ³ . Here, the density of the hollow fiber can be evaluated by measuring the density of a sample made of the hollow fiber alone.

When the polymer of the hollow fiber has hydrophilicity, hydrophilic molecules such as water molecules and alcohols are preferably easily penetrated. The term "polymer of the hollow yarn" as used herein is hydrophilic means that the hollow yarn has a moisture content of 2% or more as measured in a standard state at 20 ℃ and a relative humidity of 65%. The polymer of the hollow yarn is more preferably a polyamide such as N6 or N66.

Further, when the hollow fiber has many pores having a diameter of 100nm or less in the longitudinal direction, various molecules are more likely to permeate therethrough, and the nanofiber adsorption property and the liquid water absorption property of the hollow portion can be sufficiently exhibited, which is preferable. The pore diameter can be evaluated by observing the cross section of the fiber with an electron microscope, and by freezing point depression of water in the polymer. The pore diameter is more preferably 50nm or less, particularly preferably 10nm or less, or 10nm. This can suppress a decrease in color developability during fiber dyeing. In particular, it is preferable that the hollow filaments are made of a hydrophilic polymer such as polyamide and have more pores because moisture absorption is improved.

The method for producing the nanofiber aggregate of the present invention is not particularly limited, and for example, the following method using a polymer alloy fiber as a precursor can be used.

That is, 2 or more polymers having different solubilities in a solvent are alloyed to prepare a polymer alloy melt, and the polymer alloy melt is spun, cooled, solidified, and fiberized. Then, drawing and heat treatment are performed as necessary to obtain a polymer alloy fiber having a sea-island structure. Then, the easily soluble polymer is removed by a solvent to obtain the nanofiber aggregate of the present invention. Here, the polymer alloy fiber is preferable as the nanofiber aggregate precursor, and the following are mentioned.

That is, the polymer alloy fiber has a sea-island structure composed of 2 or more organic polymers having different solubilities, wherein the island component is a hardly soluble polymer, the sea component is a easily soluble polymer, the number average diameter of the island region is 1 to 150nm, the diameter of the island region having an area ratio of 60% or more is 1 to 150nm, and the island component is dispersed in a stripe shape.

In the present invention, it is important to form a sea-island structure from 2 organic polymers having different solubilities, and the term "solubility" as used herein means different solubilities in a solvent. The solvent may be an alkali solution, an acid solution, an organic solvent, or a supercritical fluid.

In the present invention, it is important to use a readily soluble polymer as the sea component and a poorly soluble polymer as the island component in order to remove the sea component easily with a solvent. In addition, when a polymer that is easily soluble in an alkaline aqueous solution is selected as the easily soluble polymer, explosion-proof facilities are not required for the dissolution facilities, and it is preferable from the viewpoint of cost and versatility. Examples of the alkali-soluble polymer include polyester and polycarbonate (hereinafter abbreviated as PC), and copolymerized PET and PLA are particularly preferable. Further, when a hot water-soluble polymer or a biodegradable polymer is selected as the easily soluble polymer, the load of waste liquid treatment is reduced, which is more preferable. Examples of the hot-water-soluble polymer include polyalkylene glycol, polyvinyl glycol and derivatives thereof, and 5-sodium sulfoisophthalate copolyester (5- ナトリゥムスルホィソフタル acid high-rate co- ポリェステル), and particularly, a polymer having high heat resistance, which is produced by chain extension of polyalkylene glycol via an ether bond, and PET, which is obtained by copolymerizing 5-sodium sulfoisophthalate in an amount of 10 mol% or more, are preferable. Examples of the biodegradable polymer include PLA.

In addition, when considering the yarn processability, the textile knittability, and the multi-processing processability after the production of the polymer alloy fiber, it is preferable that the melting point of the polymer constituting the sea component is 160 ℃ or more. However, as for the amorphous polymer in which a melting point is not observed, a polymer having a glass transition temperature (Tg) or a Vickers softening temperature or a heat distortion temperature of 160 ℃ or more is preferable.

On the other hand, as the polymer constituting the island component, a polymer suitable for the above-mentioned nanofibers can be used.

Further, the island Cheng Fenxing has a striped structure, and is important from the viewpoint of being a nanofiber precursor. Further, the island component dispersed in a stripe shape supports the thinning of the polymer alloy like the iron stripe, and therefore, the spinning thinning effect can be stabilized. The term "stripe-like structure" as used herein means that the ratio of the length of the island in the fiber axis direction to the diameter thereof is 4 or more. Usually, the ratio of the length to the diameter in the fiber axis direction is 10 or more, and is often outside the field of view in TEM observation.

The content of the island component in the polymer alloy fiber may be any value, but when the nanofiber is formed in consideration of the elution of the sea component, it is preferable that the content of the island component in the entire fiber is 10% by weight or more. The content of the island component is more preferably 20% by weight or more. However, when the island content is too high, islands are not formed by inversion of islands, and therefore 50 wt% or less is preferable. Further, for example, when a nonwoven fabric is produced by wet papermaking, the island content is preferably 30% by weight or less because the island content is low and is easily dispersed.

In the present invention, in order to obtain nanofibers having small variation in single fiber fineness, the number average diameter and variation of the island regions in the polymer alloy fiber are important. The evaluation method was performed in accordance with the evaluation of the variation in single fiber fineness of the nanofibers. The cross section of the polymer alloy fiber was observed by TEM, and the diameter of an island region of 300 or more randomly drawn fibers was measured in the same cross section. An example of a cross-sectional photograph of the polymer alloy fiber of the present invention is shown in FIG. 2. The measurement is performed at least at 5 points or more, and the diameter of a total of 1500 island regions or more is measured. It is preferable that the measurement is performed at positions spaced apart from each other by 10m or more in the filament length direction.

Here, the number average diameter is a simple average of the measured island region diameters. It is important that the number average diameter of the island region is 1 to 150 nm. Thereby, nanofibers having a fineness other than the original fineness can be obtained when the sea polymer is removed. The number average diameter of the island region is preferably 1 to 100nm, more preferably 20 to 80nm.

In addition, the variation in island region diameter was evaluated by the following method. In other words, the frequency (number) of each diameter is counted for each island region to be measured. The area of each island region is S ₁ Then the sum is the total area (S) ₁ +S ₂ +…S _n ). The product of the frequency (number) of the same area S and the area of the frequency is divided by the total area to obtain the area ratio of the island region. For example, the number of island regions having a diameter of 60nm is 350, and the total area is 3.64X 10 ⁶ nm ² In terms of area ratio of (3.14X 30nm X350)/(3.64X 10) ⁶ nm ² ) X 100% =27.2%. The area ratio corresponds to the volume fraction of the island region of each size to the bulk polymer alloy fiber, and the island region component having a large volume fraction has a large influence on the bulk properties when the nanofiber is produced. The polymer alloy fiber of the present invention has island regions in which the area ratio of the island regions is 60% or moreThe range of 1 to 150nm in diameter is important. This means that almost all of the single fibers in the production of nanofibers have a diameter of 150nm or less, which has not been achieved before. In the portion where the area ratio of the island region is high, a component having a smaller diameter is preferably concentrated in the island region, and an island region having an area ratio of 60% or more is preferably in the range of 1 to 100nm in diameter. The area ratio of the island region having a diameter in the range of 1 to 100nm is preferably 75% or more or 75%, more preferably 90%, particularly preferably 95% or more, most preferably 98% or more. Similarly, the island region having an area ratio of 60% or more is preferably in the range of 1 to 80nm in diameter. More preferably, the island region has an area ratio of 75% or more and a diameter in the range of 1 to 80nm.

One of the indicators of the island region diameter variation is the area ratio of the island region having the island region diameter difference of 30nm width. As described above, when the frequency of each diameter is counted for each island region and the diameter difference is divided into 30nm wide regions, the total value of the area ratios of the island regions having the highest frequency of 30nm wide is defined as the area ratio of the island region having the island region diameter difference of 30nm wide. This is a parameter corresponding to the half-value width of the degree distribution or the concentration of the deviation near the central diameter, meaning that the higher the area ratio, the smaller the deviation. In the present invention, it is preferable that the area ratio of the island region having a diameter difference of 30nm is 60% or more. More preferably 70% or more than 70%, particularly preferably 75% or more than 75%.

As described above, in the cross section of the polymer alloy fiber, the size of the island region and the variation thereof are important, but in view of the quality stability of the fiber product after the nanofiber formation, the thickness in the filament length direction is preferably small. For example, when nanofibers are used as a polishing cloth, the size and number of scratches (scratches on the surface of an object to be polished) are greatly affected by the roughness in the filament length direction. Therefore, the polymer alloy fiber of the present invention preferably has a worsted mottle of 15% or less, more preferably 5% or less, and particularly preferably 3% or less.

When the strength of the polymer alloy fiber of the present invention is 1.0cN/dtex or more and the elongation is 25% or more, the occurrence of troubles such as fuzz and yarn breakage in the steps such as crimping, twisting and knitting is reduced, which is preferable. The strength is more preferably 2.5cN/dtex or more, and particularly preferably 3cN/dtex or more, or 2.5 cN/dtex. When the boiling water shrinkage ratio (boil water shrinkage) of the polymer alloy fiber is 25% or less, the dimensional change of the fabric during the sea component elution treatment is small, which is preferable. The boiling water shrinkage is more preferably 15% or less.

The polymer alloy fiber of the present invention may be a composite fiber in which a polymer alloy that is a precursor of a nanofiber and a polymer other than the polymer alloy are bonded. For example, a polymer alloy which is a precursor of nanofibers is disposed in the core section, and polymers other than the polymer alloy are disposed in the shell section to form a core-shell composite yarn, and then, when the sea component of the polymer alloy is eluted, a special fiber in which nanofibers are encapsulated in the hollow section of the hollow yarn can be obtained. In addition, when the core and the shell are exchanged, a mixed filament in which nanofibers are arranged around a normal fiber can be easily obtained. Further, when a sea-island composite yarn is formed by using a polymer alloy as a nanofiber precursor as a sea component and other polymers as bird components, a mixed filament of nanofibers and fine fibers can be easily obtained. In this way, a mixed filament of the nanofibrils and the fine fibers or the ordinary fibers can be easily obtained. Therefore, the form stability as a fibrous structure is remarkably improved. Further, if the polymer used in the nanofibrils has a significantly different chargeability from other polymers, the dispersibility of the nanofibers may be improved due to electrostatic repulsion resulting from the potential difference on the fiber surface.

The polymer alloy fiber of the present invention can improve the degree of fluffing by crimping. In the case of false twist textured yarn, it is preferable that the crimp rigidity value (CR value) as an index of crimpability is 20% or more or 20% or more. In addition, mechanical crimped yarn and air-jet processed yarn, as the crimp index of the number of crimps is preferably 5/25 mm or more. In addition, crimping can also be imparted by making the core-shell composite filaments side-by-side or eccentric. In this case, the number of crimps is preferably 10/25 mm or more. The CR value can be adjusted by adjusting the conditions of the false twisting process such as the crimping method, the crimping device, the number of revolutions of the twister, and the heater temperature. The CR value is 20% or more by adjusting the temperature of the heater to a temperature of-70 ℃ or more (70 ℃ or less). In order to further increase the CR value, it is effective to increase the heater temperature.

Further, the number of crimps of the mechanically crimped yarn, the air-jet-processed yarn, or the like is 5/25 mm or more by appropriately changing conditions such as selection of a crimping device and a feed rate.

In the case of the parallel or eccentric core-sheath composite yarn, the difference in melt viscosity of the polymer to be bonded is 2 times or more, or the difference in thermal shrinkage at the time of spinning alone is 5% or more, whereby the number of crimps can be 10/25 mm or more.

In order to obtain a polymer alloy fiber containing almost no large island components and having island components uniformly dispersed in a nano-size, it is important to consider a combination of affinity and viscosity balance between polymers, a kneading method for achieving high kneading, and a selection of a polymer supply method, as described below.

The polymer alloy fiber of the present invention may be produced into long fibers by melt spinning and drawing, or may be produced into short fibers by mechanical crimping. Even if the short fibers are spun, they may be made into a nonwoven fabric by needle punching or wet papermaking. Alternatively, a spunbond or meltblown nonwoven fabric may be used.

The polymer alloy fiber can be easily made into a composite by mixing with other fibers, mixing with cotton, blending, interweaving, laminating, bonding, etc. This can greatly improve the form stability in the case of nanofiber formation. Further, a product having higher functions can be obtained by combining the functions.

When the sea component is removed from the polymer alloy fiber having a low island component content and the individual product is converted into a nano-sized product, the individual product has a more significant loose structure, and the morphological stability and mechanical properties may not be satisfactory for practical use. However, these problems can be solved by using, as the support, other fibers that are stable to the solvent used in the sea component elution step. Such other fibers are not particularly limited, but nylon or polyolefin stabilized by alkali treatment is preferably used for the nylon/polyester polymer alloy fibers.

For example, a nylon/polyester polymer alloy fiber and a general nylon fiber are mixed and woven to form a woven fabric or a knitted fabric, and a nylon nanofiber product is produced through a dissolution step from these fibers.

Further, a nonwoven fabric made of a nanofiber aggregate and a nonwoven fabric made of other fibers can be obtained by subjecting a nonwoven fabric made of polymer alloy fibers to a leaching step after forming a laminated nonwoven fabric by laminating a nonwoven fabric made of other fibers on the nonwoven fabric. For example, when a PP nonwoven fabric is bonded to a nonwoven fabric made of nylon/polyester polymer alloy fibers, the form stability of nylon Long nanofibers is improved rapidly when the polyester is dissolved with an alkali. In particular, when the content of nylon (island component) in the polymer alloy fiber is low, the individual product is nanofibrillated to form a significantly loose structure, and the morphological stability and mechanical properties may not be satisfactory for practical use. The nylon Long nanofiber/PP laminated nonwoven fabric thus obtained has high hydrophilicity and high adhesiveness on the nylon side, but has low hydrophobicity and low adhesiveness on the PP side, and is a high-performance nonwoven fabric satisfying the opposite characteristics of both, and is useful not only as an industrial material but also as a garment. In addition, a bonding agent such as a thermal bonding fiber may be used for the lamination method. In addition, if the form stability and mechanical properties are merely improved, a so-called mixed cotton nonwoven fabric may be used, but when the functionality is desired, a laminated nonwoven fabric is preferable.

The polymer alloy fiber of the present invention is useful not only as a nanofiber precursor but also as a polymer alloy fiber since polymers having different properties are uniformly dispersed in a nano-size. For example, when nylon or polyester is uniformly dispersed in PLA in a nano size, poor heat resistance, which is a drawback of PLA, can be improved. In addition, when the polyester is uniformly dispersed in the nylon in a nano size, poor dimensional stability upon water absorption, which is a drawback of nylon, can be improved. In addition, when nylon or polyester is uniformly dispersed in polystyrene (hereinafter referred to as PS) in a nano size, brittleness, which is a disadvantage of PS, can be improved. When nylon or polyester is uniformly dispersed in PP in a nano size, dyeability, which is a disadvantage of PP, can be improved.

The polymer alloy fiber of the present invention can form various fiber structures as in the case of the nanofiber aggregate. The fiber structure comprising the polymer alloy fiber of the present invention can be used as intermediate products such as silk, cotton (cotton), packaging materials, woven fabrics, knitted fabrics, felts, nonwoven fabrics, artificial leathers, and sheets. Further, the fiber-reinforced thermoplastic resin composition is also suitable for use as clothing, clothing materials, interior products for vehicles, living materials, environmental and industrial materials, IT parts, and medical products.

Here, in the polymer alloy fiber as a precursor of the nanofiber aggregate, it is important to control the island component size. Here, the island component size was evaluated by observing the cross section of the polymer alloy fiber with a Transmission Electron Microscope (TEM) and converting the diameter. Since the diameter of the nanofibers can be approximately determined by the size of the islands in the precursor, the size distribution of the islands can be designed according to the nanofiber diameter distribution of the present invention. Therefore, kneading of the alloyed polymer is very important, and deep kneading using a kneading extruder, a static kneader or the like is preferable in the present invention. In addition, in the conventional examples such as Japanese unexamined patent publication No. 6-272114, kneading by simple mixing of chips (dry mixing) is insufficient, and it is difficult to disperse islands in a size of several tens of nm as in the present invention.

Therefore, it is preferable to highly knead the mixture by using a twin-screw extruder or a static kneader divided into 100 to 100 ten thousand parts. In order to avoid mixing unevenness and variation in mixing ratio with time, it is preferable that each polymer is independently metered and independently supplied to the kneading apparatus. In this case, the polymers may be supplied separately as pellets or separately in a molten state. Further, 2 or more kinds of polymers may be supplied to the main body of the extrusion kneader, or one component may be supplied as a side feed from the middle of the extrusion kneader.

When a biaxial extruder is used as the kneading apparatus, it is preferable that the kneading is carried out at a high degree and the residence time of the polymer is suppressed. The screw is composed of a conveying section and a kneading section, but the kneading section length is preferably 20% or more of the effective screw length, and high kneading is possible. Further, by setting the kneading section length to 40% or less of the effective screw length, excessive shear stress can be avoided, and the residence time can be shortened, whereby thermal aging of the polymer and gelation of the polyamide component and the like can be suppressed. Further, by providing the kneading section as far as possible on the discharge side of the twin-screw extruder, the residence time after kneading can be shortened, and the re-aggregation of the island polymer can be suppressed. In the case of intensive kneading, a reverse-flow screw for conveying the polymer in the reverse direction may be provided in the extruder-kneader.

In addition, when kneading is carried out by a vent extruder, hydrolysis of the polymer is suppressed by sucking a decomposition gas or reducing water in the polymer, and the amount of amine end groups in the polyamide and carboxylic acid end groups in the polyester is also suppressed.

In addition, b is used as an index of coloring the polymer alloy particles ^* The value is 10 or less than 10, and can beIt is preferable to adjust the color tone during fiberization. The easily soluble component is preferably a hot-water-soluble polymer, which generally has poor heat resistance and is easily colored in view of its molecular structure, but the coloring can be suppressed by shortening the retention time.

These kneading devices may be provided independently of the spinning machine, and may be supplied to the spinning machine after the polymer alloy pellets are once produced, or may be connected to the spinning machine to directly spin the kneaded molten polymer. Alternatively, when a static mixer is used, it may be inserted into the tube of the spinning machine or into the spin pack.

In order to reduce the cost of the spinning process, the following method may be used when kneading the pellets by mixing (dry mixing).

That is, the mixed polymer particles are independently metered and supplied, and are temporarily stored in a mixing tank, where they are sliced and mixed. In this case, the mixing efficiency can be improved while suppressing the mixing unevenness as much as possible by setting the capacity of the mixing tank to 5 to 20kg. The mixed pellets were fed from the mixing tank to an extrusion kneader to prepare a molten polymer. Here, the molten polymer may be kneaded by a twin-screw extruder or a static kneader inserted into a pipe or a tank. In this case, precursor particles having a large amount of the easily soluble polymer to be mixed may be used.

In addition, the residence time from the formation and melting of the polymer alloy to the discharge from the spinning nozzle is also important from the viewpoint of suppressing the re-aggregation of the island polymer during spinning and suppressing the generation of coarse aggregated polymer particles. It is preferable that the time from the tip of the polymer alloy melt section to the time of ejection from the spinning nozzle be 30 minutes or less.

In addition, in order to uniformly disperse the island polymer in a nano size, a combination of compositions is also important, and by increasing the affinity between the poorly soluble polymer and the easily soluble polymer, the easily soluble polymer as the island component is easily dispersed in a nano size. In order to make the cross section of the island region nearly circular, the island component and the sea component are preferably immiscible. However, it is difficult to disperse the island component in a nano size by a combination of simple immiscible polymers. Therefore, it is preferable to optimize the compatibility of the combined polymers, and one of the indices is the solubility parameter (SP value). The SP value is defined as (evaporation energy/molar volume) ^1/2 The SP values are close to each other, and a polymer alloy having good compatibility can be obtained. The SP values of many polymers are known, for example, from the handbook of plastics, co-edited by Asahi Kasei ァミダス, co., ltd./plastics editor, page 189. When the SP value difference of the 2 polymers is 1 to 9 (MJ/m) ³ ) ^1/2 In the case of the metal oxide, it is preferable that the metal oxide be immiscible so that the island region is rounded and easily dispersed uniformly in a nanometer size. For example, the difference between the SP values of N6 and PET is 6 (MJ/m) ³ ) ^1/2 The preferred examples are shown on the left and right sides, and the difference between the SP values of N6 and PE is 11 (MJ/m) ³ ) ^1/2The left and right are not preferred examples. Of course, the affinity between the polymers can be controlled to some extent by the use of various copolymerization and compatibilizing agents in combination.

When the difference in melting point between the polymers constituting the island component and the sea component is 20 ℃ or less, particularly when kneading is performed using an extruder-kneader, the difference in melting state is difficult to occur in the extruder-kneader, and thus kneading is easy to perform efficiently, which is preferable. In addition, when a polymer which is easily thermally decomposed or thermally aged is used as one component, kneading and spinning temperatures must be lowered, which is also advantageous.

Further, the melt viscosity is also important, and when the melt viscosity of the hardly soluble polymer forming the island component is set to a low value, the island component is easily deformed by a shearing force, and the island component is easily finely dispersed, which is preferable from the viewpoint of making the island component nano. However, when the island component melt viscosity is too low, the island component easily becomes sea, and the mixing ratio to the whole fibers cannot be high, so that the island component polymer melt viscosity is preferably 0.1 or more, more preferably 0.5 to 1.5 of the sea component polymer melt viscosity.

On the other hand, the absolute value of the melt viscosity of the easily soluble polymer forming the sea component is also important, and a polymer having a low viscosity of 100 pas or less is preferable. Therefore, the island polymer can be dispersed very easily, or the polymer alloy can be deformed smoothly during spinning, and the spinnability can be improved significantly as compared with the case of using a polymer having a normal viscosity. At this time, the melt viscosity of the polymer was 1216 seconds at the nozzle face temperature ^-1 The value of (c).

Since the island component and the sea component are immiscible in the polymer alloy, the island component is aggregated with each other and is thermodynamically stable. However, since the island polymer is dispersed in an arbitrary nano size, the gold alloy forms many very unstable polymer interfaces as compared with a polymer mixture having a large dispersion diameter. Therefore, when a polymer alloy is simply spun, a large polymer flow expands (puffing phenomenon) after the polymer is discharged from a nozzle due to a large number of unstable polymer interfaces, or spinning defects occur due to unstable polymer alloy surfaces, which results in excessively large yarn knots and thus the spinning itself may not be performed. In order to avoid this problem, it is preferable that the shear stress between the nozzle hole wall and the polymer at the time of ejection from the nozzle be 0.2MPa or less or 0.2MPa or less. Here, the shear stress between the nozzle bore wall and the polymer can be from Ha Jinbo, (ハ - ゲンポヮズュ: hagen-Poiseuille) type (shear stress (dynes/cm) ² ) = R × P/2L). Also, R: radius (cm) of a nozzle orifice, P: pressure loss (MPa) of nozzle orifice, L: is a nozzleThe ejection hole is long (cm). In addition, P = (8L η Q/. Pi.R) ⁴ ) Eta is the polymer viscosity (poise), Q is the ejection rate (cm) ³ Per second), pi is the circumference ratio. In addition, 1 dyne/cm of CGS unit system ² SI units are 0.1Pa.

In the case of ordinary polyester single-component melt spinning, the shear stress between the nozzle hole wall and the polymer is set to 1MPa or more, and the metering property and the spinning property can be secured. However, unlike the conventional polyester, the polymer alloy of the present invention is liable to break the viscoelastic balance when the shear stress between the nozzle hole wall and the polymer is large, and the shear stress must be reduced as compared with the conventional polyester melt spinning. When the shear stress is 0.2MPa or less, it is preferable that the flow of the nozzle Kong Bice and the polymer flow velocity in the center of the nozzle hole are uniform, the shear variation is small, the puffing phenomenon is relaxed, and a good spinning property can be obtained. The shear stress is more preferably 0.1MPa or less or 0.1MPa or less. In general, in order to further reduce the shearing stress, the discharge hole diameter of the nozzle is increased and the discharge length of the nozzle is shortened, but if excessive progress is made, the metering property of the polymer at the discharge hole of the nozzle is lowered and the fineness unevenness tends to occur between the holes, so that it is preferable to use a nozzle in which a polymer metering portion smaller than the discharge hole diameter of the nozzle is provided at the upper portion of the discharge hole of the nozzle. When the shear stress between the nozzle hole wall and the polymer is 0.01MPa or more, the polymer alloy fiber can be stably melt-spun, and the Worcester Spot (U%) as an index of knot Spot of the filament is preferably 15% or less or 15%.

As described above, when melt-spinning the polymer alloy uniformly dispersed in the nano-size used in the present invention, it is important to suppress the shear stress at the time of nozzle discharge, but it is also preferable to adjust the cooling conditions of the filaments. In the case of melt spinning a general polyester, since elastic vibration is suppressed, cooling is generally slow. However, in the present invention, since the polymer alloy uniformly dispersed in the nano size is a very unstable molten fluid, rapid cooling solidification after ejection from the nozzle is preferable. The distance from the lower side of the nozzle to the start of cooling is preferably 1 to 15cm. When the distance from the lower surface of the nozzle to the start of cooling is 1cm or more, it is preferable that the temperature unevenness of the nozzle surface is suppressed and the yarn having a small yarn pitch unevenness is obtained. When the thickness is 15cm or less, the filament is preferably cured quickly, so that the thinning of the marvellous unstable filaments is suppressed, the drawability is improved, and the filaments with small knot unevenness can be obtained. Here, the cooling start position means a position where active cooling of the yarn starts, but when an actual melt spinning device is used, it means an upper end portion of the air duct.

From the viewpoint of sufficiently ensuring the spinning performance and spinning stability of the melt spinning, it is preferable that the nozzle surface temperature (surface temperature of the central portion of the nozzle discharge surface) is not less than the melting point (Tm) +20 ℃ of the multicomponent polymer. Further, when the nozzle surface temperature is not more than the melting point (Tm) +80 ℃ of the multicomponent polymer, the pyrolysis of the polymer can be suppressed, which is more preferable.

From the viewpoint of the reduction in the number average diameter of the island regions in the polymer alloy fiber, the higher the aeration during spinning, the higher the aeration is, and it is preferable to be 100 or more. Therefore, it is preferable to perform high-speed spinning.

Further, it is preferable to draw and heat-treat the spun polymer alloy fiber, but it is preferable that the preheating temperature at the time of drawing is not lower than the glass transition temperature (Tg) of the polymer constituting the island component, because the occurrence of the filament unevenness can be suppressed. Further, the polymer alloy fiber may be subjected to a filament processing such as crimping. When the heat treatment temperature in the crimping process is set to a temperature exceeding ((melting point of polymer constituting sea component) — 30 ℃), melt adhesion, yarn breakage, and fuzz can be suppressed, which is preferable.

As described above, the preferred melt spinning methods for the polymer alloy fibers of the present invention are summarized below.

A process for producing a polymer alloy fiber, which comprises melt-spinning a polymer alloy obtained by melt-mixing a poorly soluble polymer and a readily soluble polymer, characterized in that the following conditions (1) to (3) are satisfied.

(1) Separately metering the insoluble polymer and the soluble polymer, and separately feeding them to a mixing device for melt mixing;

(2) The content of the hardly soluble polymer in the polymer alloy is in the range of 10 to 50% by weight;

When melt-mixing is carried out using a twin-screw extruder, the length of the kneading section of the twin-screw extruder is preferably 20 to 40% of the effective length of the screw.

When melt-mixing is carried out using a static mixer, the number of divisions of the static mixer is preferably 100 to 100 ten thousand.

In addition, the present invention relates to a method for melt-spinning a polymer alloy fiber, which comprises, in the case of mixing chips, providing a mixing tank before melting the pellets, temporarily storing 2 or more kinds of pellets therein, dry-mixing the pellets, supplying the dry-mixed pellets to a melting section, and melt-spinning a mixture of a hardly soluble polymer and a easily soluble polymer while satisfying the following conditions (4) to (6).

(4) The mixing ratio of the hardly soluble polymer in the fiber is 10 to 50 wt%;

(5) The melt viscosity of the easily soluble polymer is 100 pas or less than 100 pas, or the melting point of the easily soluble polymer is in the range of-20 to +20 ℃ of the melting point of the hardly soluble polymer;

(6) Mixing tank capacity of pellets = pellets 5 to 20kg.

The method of the present invention can obtain a polymer alloy fiber having a small filament unevenness by uniformly dispersing island components in a size of several tens nm by combining the above polymers and optimizing spinning and drawing conditions. Therefore, by using a polymer alloy fiber having a small unevenness in the longitudinal direction of the filament as a precursor, a nanofiber assembly having a small variation in the single fiber fineness can be obtained not only at a certain cross section but also at any cross section in the longitudinal direction. In addition, according to the method for producing a nanofiber assembly of the present invention, completely different from nanofibers produced by electrospinning, drawing and heat treatment of polymer alloy fibers as precursors are also possible, and therefore, tensile strength and shrinkage can be freely controlled. Therefore, nanofibers having the above excellent mechanical properties and shrinkage properties can be obtained.

From the polymer alloy fiber thus obtained, a readily soluble polymer as a sea component is dissolved out with a solvent, and a nanofiber aggregate is obtained. In this case, an aqueous solvent can be used as the solvent, and is preferable from the viewpoint of reducing environmental load. In particular, an aqueous alkali solution or hot water is preferable. Therefore, as the easily soluble polymer, a polymer which can be hydrolyzed by alkali such as polyester, or a hot water soluble polymer such as polyalkylene glycol, polyvinyl alcohol, and derivatives thereof is preferable.

The dissolution of the easily soluble polymer may be performed in the stage of yarn or cotton, in the stage of fabric such as woven fabric, knitted fabric or nonwoven fabric, or in the stage of a thermoformed article. Further, the dissolution rate of the polymer alloy fiber based on the weight is 20 wt%/hour or less, whereby a nanofiber assembly having excellent production efficiency can be obtained.

Therefore, in order to further disperse the nanofiber aggregate into nanofibers one by one from a long fiber shape and/or a spun yarn shape, it can be achieved from a nonwoven fabric using the following wet papermaking method. That is, the present invention relates to a method for producing a nonwoven fabric, in which the polymer alloy fiber of the present invention is cut into a fiber length of 10mm or less, and then the easily soluble polymer is eluted, and then the obtained nanofibers are subjected to papermaking without primary drying. When this method is employed, the diameter of the nanofiber aggregate can be sufficiently dispersed to 1 μm or less than 1 μm. In addition, when a dispersion liquid having high affinity with the polymer constituting the nanofibers is used, the diameter of the nanofiber assembly may be dispersed to 300nm or less than 300 nm.

The nanofiber aggregate of the present invention exhibits excellent adsorption/absorption characteristics, and therefore can carry various functional drugs. The functional agent as used herein means a substance capable of improving the function of the fiber, and examples thereof include a moisture absorbent, a moisture retention agent, a flame retardant, a water repellent, a cold retention agent, a heat retention agent, and a smoothing agent. The properties of the functional drug are not limited to fine particles, and drugs for health care or beauty care such as polyphenol, amino acid, protein, capsaicin, and vitamins, and drugs for skin diseases such as pimples can be used. In addition, it can be used as medicinal products such as disinfectant, antiinflammatory agent, and analgesic. Alternatively, the compound can be used as a drug for adsorbing and decomposing harmful substances such as polyamine and photocatalyst nanoparticles.

The method for supporting the functional agent is not particularly limited, and the functional agent may be supported on the nanofibers by post-processing by bath treatment or coating treatment, or may be contained in the polymer alloy fibers of the nanofiber precursor. Alternatively, the functional drug may be directly supported on the nanofiber aggregate, or a precursor of the functional drug may be supported on the nanofibers and then the precursor may be converted into a desired functional drug.

Specific examples of the latter method include a method in which an organic monomer is impregnated in a nanofiber aggregate and then polymerized; and a method of treating a readily soluble substance in a bath, immersing the substance in a nanofiber aggregate, and then performing a redox reaction or ligand substitution to make the substance less soluble by an ion exchange reaction or the like. Examples of the organic monomer include various organic monomers and metal alkoxide compounds partially substituted with hydrocarbon. In addition, when a precursor of a functional agent is carried in the spinning process, a molecular structure having high heat resistance is formed in the spinning process, and a method of returning to the molecular structure having functionality by post-processing may be employed.

For example, in order to impart moisture absorption to a fabric made of a general polyester fiber, even a polyethylene glycol (hereinafter, sometimes referred to as PET) based moisture absorbent having a molecular weight of 1000 or more is hardly absorbed. However, when the same moisture absorbent is applied to the fabric made of nanofibers of the present invention, a large amount of moisture can be absorbed.

Recently, squalene, a natural oil component extracted from shark liver, has attracted attention as a substance having a skin-caring function by moisturizing. Even if squalene is added to a fabric made of a general polyester fiber, it is hardly absorbed, but a fabric made of the nanofiber of the present invention can be absorbed in a large amount, and the washing durability is greatly improved. This is very surprising for substances that have affinity for normal polyester fibres.

Further, by impregnating the nanofiber aggregate with an alkyl-substituted metal alkoxide compound and polymerizing the same, a silicone polymer or silicone oil can be supported on the nanofiber aggregate, and the durability in washing is also good. In the conventional processing, it was extremely difficult to support silicone in a fiber with excellent durability, but the nanofiber aggregate of the present invention was used, and it became possible to start with this. Similarly, it is possible to mix with other organic materials such as polyurethane.

In addition, the nanofiber assembly of the present invention can be added with various functional agents and has excellent sustained release properties. By using the above-mentioned various functional agents, the sustained-release agent can be applied to an excellent sustained-release base material or drug delivery system.

In addition, when the monomer or oligomer having an inorganic polymer-forming ability is absorbed by the nanofiber aggregate of the present invention and polymerized, an inorganic substance is present in the inside of the nanofiber aggregate. That is, an organic/inorganic hybrid fiber in which an inorganic substance is dispersed in a nanofiber aggregate can be obtained. In this case, the nanofiber content in the mixed fiber can be adjusted by adjusting the absorption capacity of the inorganic monomer in order to exhibit desired performance. Examples of the monomer or oligomer having an inorganic polymer-forming ability include metal alkoxides and oligomers thereof or metal salt solutions thereof. Further, the type in which these monomers and oligomers are polymerized by heating is preferable from the viewpoint of production efficiency, but a type in which these monomers and oligomers are insolubilized by a redox reaction, counter ion exchange or ligand exchange in a solution may be used. The former may be exemplified by silicate, and the latter may be exemplified by platinum chloride, silver nitrate, or the like.

Therefore, when the content of the nanofiber aggregate is 5 to 95% by weight, an organic/inorganic hybrid fiber in which at least a part of the inorganic substance is dispersed in the nanofiber aggregate can be obtained. Here, when describing the organic/inorganic hybrid state in more detail, the inorganic substance is impregnated into the gap between the nanofibers, in which the inorganic substance is in a form of being bonded to the nanofibers or in a form of the nanofibers being dispersed in the inorganic substance matrix. Therefore, the inorganic substance is communicated from the surface to the inside of the organic/inorganic hybrid fiber, thereby sufficiently utilizing the characteristics of the inorganic substance. For example, the blended fiber of nanofibers and hygroscopic silica can be used as it is to flexibly utilize the excellent moisture absorption rate and moisture absorption rate of the hygroscopic silica.

The content of the nanofibers in the organic/inorganic hybrid fiber of the present invention is preferably 5 to 95 wt%. This makes it possible to obtain both excellent inorganic properties and excellent flexibility of the organic fibers. The nanofiber content is preferably 20 to 90% by weight, more preferably 25 to 80% by weight.

The organic/inorganic hybrid fiber of the present invention can be used not only as a unitary fiber but also as a binary fiber structure such as a knitted fabric or a nonwoven fabric, and a sheet-like structure. Of course, a ternary structure such as a component, a member, a thermoformed article, or cotton can be produced using these.

In addition, as a method of impregnating the nanofiber aggregate with the inorganic monomer, for example, a method of preparing a monomer solution and impregnating or immersing the nanofiber aggregate in the monomer solution may be mentioned, and a high-order processing apparatus such as dyeing or coating of a general fiber product may be used. As the solution, for example, an aqueous solution, an organic solvent solution, a supercritical fluid solution, or the like can be used.

In the polymerization of the monomer impregnated in the nanofiber aggregate, polymerization is carried out at a low temperature such as a sol-gel method, and since the temperature is not lower than the melting point of the nanofibers or higher, it is preferable from the viewpoint of suppressing coagulation due to melting or flowing of the nanofibers. In addition, in reducing metal chloride, etc., can be at the melting point of nanofiber or below reduction, and, in addition, avoid to use the nanofiber modified by strong acid, alkali, selection of slow and moderate conditions is preferred. The sol-gel method is described in detail in "ソル - ゲル" science of the art (written by Huaji fu, ァグネ Shufeng) ", and the like.

The organic/inorganic hybrid fiber of the present invention may be used as it is, or may be prepared into an inorganic porous fiber by removing a nano component therefrom.

90% by weight or more of the composition of the inorganic porous fibers is an inorganic substance such as a metal, a metal oxide, a metal halide, or a metal complex, and is important from the viewpoint of improving heat resistance. Further, when the number average diameter of the pores is 1 to 5000nm in the minor axis cross-sectional direction, the specific surface area becomes large, the adsorption property is improved, and it is preferable from the viewpoint of weight reduction. The number average diameter of the fine pores is more preferably 1 to 100nm. The short axis cross-sectional direction herein means a radial direction of the nanofibers used in the mold.

When the fiber length of the inorganic porous fiber is 1mm or more, the form of the fiber product can be maintained, which is preferable. The fiber length is preferably 10cm or more than 10 cm.

Here, as a method for removing the nanofiber component, a method of removing the nanofiber by gasifying it by burning or a method of removing it by extraction with a solvent can be used. The burning temperature also depends on the organic polymer composition, and may be about 500 to 1000 ℃. Further, since shrinkage generally occurs by burning, the pore size of the nanofiber removed by the burning temperature can be controlled. As the burning device, a conventionally known burning device for a metal oxide such as silica or titania, a carbon fiber, or the like can be used. In addition, when extraction is performed, it is preferable to use a good solvent for the organic polymer, for example, when the organic polymer is nylon, acid such as formic acid; when the polyester is adopted, an alkaline aqueous solution or halogenated organic solvents such as o-chlorophenol and the like are adopted; in the case of PP, an organic solvent such as toluene is used. As the extraction apparatus, a conventional high-order processing apparatus for woven fabric can be used.

The organic/inorganic hybrid fiber or inorganic porous fiber of the present invention can be used in various fiber structures such as a knitted fabric, a nonwoven fabric and the like, or a thermoformed article and the like, similarly to the nanofiber aggregate, and therefore, can be widely used as a cloth, a module, a laminate with other materials and the like. Further, it is effective in utilizing its adsorption property and moisture absorption property, and is used for indoor decoration such as curtains, wall papers, carpets, cushions, and furniture for improving the residential environment, and also used for organic filters for removing organic contaminants for clean rooms. Further, the sheet is also useful as a toilet and an indoor deodorizing sheet, and as a vehicle interior material for improving the environment in a vehicle, more specifically, as a seat cover, a ceiling covering, or the like. Further, the present invention can be used for comfortable clothes having a certain deodorizing ability, and clothes materials such as caps and pads. In addition, the metal conductivity of the material can be used as an electromagnetic wave shielding material. Further, the cell-adsorbing material can be used in industrial materials such as filters and sensors, and in medicines such as cell-adsorbing materials.

The present invention will be described in detail below with reference to examples. In the examples, the following methods were used for the measurement.

A. Melt viscosity of Polymer

The melt viscosity of the polymer was measured using a donyo seiki machine キャビログラフ B. Also, the polymer residence time from the sample placement to the start of the measurement was 10 minutes.

B. Melting Point

The melting point of the polymer was determined by Perkin Elmaer DSC-7, which shows the peak temperature of the polymer melting at 2 nd rotation. The temperature rise rate at this time was 16 ℃/min, and the sample amount was 10mg.

C. Shear stress of nozzle orifice

Shear stress between the nozzle bore wall and the polymer can be achieved by Ha Jinbo eleven (shear stress (dyne/cm) ² ) = R × P/2L). Also, R: radius (cm) of a nozzle orifice, P: pressure loss (dyne/cm) of the orifice of the nozzle ² ) L, L: the length (cm) of the ejection hole of the nozzle. In addition, P = (8L η Q/. Pi.R) ⁴ ) Eta is the viscosity (poise) of the polymer, and Q is the discharge (cm) ³ Per second), pi is the circumference ratio. Here, the polymer viscosity was measured by the temperature (. Degree. C.) of the nozzle orifice and the shear rate (seconds) ^-1 ) The value of time.

1 dyne/cm of CGS unit system ² 0.1Pa in SI units. The melt viscosity of the polymer alloy when kneading and spinning were carried out as they were (examples 8 to 16, comparative examples 2 to 4, etc.) was measured with キャビログラフ B, which was a sample of a cut yarn obtained by rapidly solidifying 10cm below a nozzle without winding a spun yarn.

D. Worcester spots (U%)

The measurement was carried out in a regular manner using a USTER TESTER 4 manufactured by ッェルベガ - ゥスタ, a Kokukukusho, with a yarn speed of 200 m/min.

E. Fiber section observation by TEM

An ultrathin section was cut in the cross-sectional direction of the fiber, and the cross-section of the fiber was observed with a Transmission Electron Microscope (TEM). In addition, metal dyeing is performed as necessary.

TEM device: h-7100FA model, manufactured by Hitachi Ltd

F. Number average single fiber fineness and single fiber diameter of nanofibers

The average single fiber fineness was determined by the following method. That is, the diameter and fineness of a single fiber were calculated by using image processing software (WINROOF) from a cross-sectional photograph of a fiber observed by TEM, and the simple average values thereof were obtained. This value was defined as "number average single fiber fineness and single fiber diameter". In this case, the number of nanofibers used for averaging was arbitrarily extracted 300 or more in the same cross section, and the diameter of a single fiber was measured. The measurement is performed at 5 positions separated from each other by 10cm or more as the length of the nanofiber aggregate, and is calculated by using the diameters of single fibers of 1500 or more in total.

G. Single fiber fineness deviation of nanofibers

The single fiber fineness variation of the nanofibers was evaluated by the following method. That is, dt is used for the single fiber fineness of each single fiber using the data obtained when the number average single fiber fineness is obtained ₁ The total titer (dt) is shown as the sum ₁+dt ₂ +dt ₃ +…dt _n ). The fineness ratio of the single fiber was determined by counting the frequency (number) of the fineness of the nanofibers having the same single fiber fineness and dividing the product of the single fiber fineness and the frequency by the total fineness.

H. Diameter variation width of nanofiber

The width of the diameter variation of the nanofibers was evaluated by the following method. That is, evaluation was performed using the fineness ratio of a single fiber having a single fiber diameter difference of 30nm width in the vicinity of the center value of the single fiber diameter of the nanofiber. This means the concentration of deviation around the central titre. The higher the fineness ratio, the smaller the variation, and the numerical value used for obtaining the above-mentioned number average single fiber fineness may be used, and as described above, the frequency of each single fiber fineness is counted and when the single fiber fineness is divided by a diameter difference of 30nm, the total value of the single fiber fineness of 30nm wide having particularly high frequency is taken as the fineness ratio of the single fiber fineness having a single fiber diameter difference of 30nm wide.

I. Number average diameter of island region

The number average diameter of the island region is determined as follows. That is, a cross-sectional photograph of the fiber observed by TEM was processed by image processing software (WINROOF), and the island region was converted into a circle to determine the diameter. The simple average value was obtained. In this case, the number of island regions used for averaging is 300 or more island regions arbitrarily extracted within the same transverse plane. The measurement is performed at 5 positions separated from each other by 10m or more in the longitudinal direction of the polymer alloy fiber, and is calculated using the island region diameter of 1500 or more in total.

J. Diameter variation of island region

The diameter variation of the island region was evaluated by the following method. That is, the cross-sectional area of each island component is S by using the value used for determining the number average diameter _i The sum of which is the total area (S) ₁ +S ₂ +…S _n ). The product of the frequency (number) and the area of the island regions having the same diameter (area) is divided by the total fineness, and the obtained value is used as the area ratio of the island regions.

K. Diameter variation width of island region

The width of the diameter variation of the island region was evaluated by the following method. That is, the evaluation was made using the area ratio of the island region in which the difference in the island region diameter is 30nm wide near the center value of the number average diameter of the island region or in the portion having a high area ratio. This may also be the data used in the above number average diameter. As described above, when the frequency of each diameter is counted for each island region and divided by the diameter difference of 30nm, the total value of the area ratios of the 30nm wide island regions having particularly high frequencies is defined as the area ratio of the island region having the island region diameter difference of 30nm wide. For example, 55 to 84nm means a range of island region diameter difference of 55nm to 84nm of 30 nm. The area ratio indicates the area ratio of the island region in the diameter range.

L.SEM Observation

Platinum-palladium alloy was vapor-deposited on the fiber, and the side surface of the fiber was observed with a scanning electron microscope.

SEM device: model S-4000, manufactured by Hitachi, ltd

M. mechanical characteristics

The weight of the nanofiber aggregate 10m was measured n =5 times, and the fineness (dtex) of the nanofiber aggregate was determined from the average value thereof. The polymer alloy fiber was cut into 100m portions to obtain a sample, and the weight of the sample was measured n =5 times, and the fineness (dtex) of the fiber was determined from the average value thereof. Then, the load-elongation curve was determined under the conditions shown in JIS L1013 at room temperature (25 ℃), initial sample length =200mm, and stretching speed =200 mm/min. Then, the load value at break was divided by the initial fineness to obtain the strength, and the elongation at break was divided by the initial sample length to obtain the elongation at break curve.

N. wide angle X-ray diffraction pattern

WAXD photographs were taken under the following conditions using a 4036A 2X-ray diffraction apparatus manufactured by Yokoku corporation.

An X-ray source: cu-Kalpha line (Ni filter)

And (3) outputting: 40kV x 20mA

And (3) cracking: 1mm phi, pinhole collimator

Radius of camera: 40mm

Exposure time: 8 minutes

Film making: kodak DEF-5

Crystal size of O

The diffraction intensity in the equatorial direction was measured under the following conditions using a 4036A 2X-ray diffraction apparatus manufactured by Yokoku corporation.

An X-ray source: cu-Kalpha line (Ni filter)

And (3) outputting: 40kV x 20mA

And (3) cracking: 1mm phi-1 °

A detector: scintillation counting tube

A count recording device: RAD-C type manufactured by Physics electric agency

Step-by-step scanning: 0.05 degree per step

Cumulative time: 2 seconds

(200) The in-plane crystallite size L was calculated using the Scherrer formula:

L＝Kλ/(β ₀ cosθ _B )

l: crystal size (nm)

K: constant =1.0

λ: wavelength of X-ray =0.15418nm

θ _B : black corner

β _o ＝(β _E ² -β _I ² ) ^1/2

β _E : apparent half-value Width (measured value)

β _I : device constant =1.046 × 10 ^-2 Reed's reaction

Degree of crystalline orientation

(200) The degree of crystal orientation in the plane direction was determined by the following method.

The half width of the intensity distribution obtained by scanning the peak corresponding to the (200) plane in the circumferential direction was calculated from the following equation using the same apparatus as that used for the measurement of the crystal size.

Degree of crystal orientation (. Pi.) = (180-H)/180

H: half value width (degree)

Measurement range: 0 to 180 DEG

Step-by-step scanning: 0.5 degree per step

Cumulative time: 2 seconds

Rouland method crystallinity (x)

< sample preparation >

The sample was cut with a razor, frozen and pulverized to obtain powder. The resulting mixture was filled in a jig made of aluminum (20 mm. Times.18 mm. Times.1.5 mm) and subjected to measurement.

< measuring apparatus >

An X-ray generating device: RU-200 (whirling counter-cathode type) manufactured by Physics Motor society

An X-ray source: cu-Kalpha line (using graphite bend crystallization monochromator)

And (3) outputting: 50kV 200mA

Angle measuring instrument: model 2155D manufactured by Yokoku Motor Co., ltd

And (3) cracking: 1-0.15-1-0.45 mm

A detector: scintillation counting tube

A counting and recording device: RAD-B model manufactured by Physics electric machinery

2q/q: continuous scanning

Measurement range: 2q = 5-145 °

Pulse modulation: 0.02 degree

Scanning speed: 2 DEG/min

< analysis >

The crystallinity was analyzed by the Ruland method. The crystallinity (x) is calculated as follows:

D＝exp(-ks ² )

s: wave number (= 2sin 0/lambda)

λ: wavelength of X ray (Cu: 1.5418A)

I(s): interference X-ray scattering intensity from sample

Ic(s): interference X-ray scattering intensity from crystals

Second order average atomic scattering factor

In the analysis, the measured data is corrected by a polarization factor, an absorption factor and air scattering. Then, compton scattering was removed, amorphous curve separation was performed, and crystallinity evaluation was performed from the intensity ratio of the crystalline diffraction peak and the amorphous scattering.

R. shrinkage in boiling water

The sample was wound 10 times with a measuring tape having a circumference of 1m to prepare a skein. Then, a load of 1/10 of the total fineness was hung on the skein, and the original length (L0) was measured. Then, the skein was left unloaded, treated in a boiling water bath at 98 ℃ for 15 minutes, air-dried, and the treated length (L1) was measured under a load of 1/10 of the total fiber length as in the original length. Then, the calculation is performed as follows.

Boiling Water shrinkage (%) = ((L0-L1)/L0) × 100 (%)

Dry heat shrinkage at S.140 ℃

The sample was marked at a width of 10cm, treated in an oven at 140 ℃ for 15 minutes in a state without a load, and the length (L2) between the marks was measured. Then, the calculation is performed as follows:

dry heat shrinkage at 140 ℃ of (%) = ((L0-L2)/L0). Times.100 (%)

Moisture absorption Rate (. DELTA.MR)

About 1 to 2g of the sample was weighed in a weighing bottle, and the sample was held at 110 ℃ for 2 hours to measure the dry weight (W0), and then the target substance was held at 20 ℃ and a relative humidity of 65% for 24 hours to measure the weight (W65). Then, the target substance was held at 30 ℃ and 90% relative humidity for 24 hours, and then the weight (W90) was measured. Then, the moisture absorption rate Δ MR was calculated as follows:

MR65＝[(W65-W0)/W0]×100％ (1)

MR90＝[(W90-W0)/W0]×100％ (2)

ΔMR＝MR90-MR65 (3)

reversible water expansibility and expansion ratio in filament length direction

The original length (L3) was measured after drying the sample fiber at 60 ℃ for 4 hours. Then, the fiber was immersed in water at 25 ℃ for 10 minutes, and then taken out of the water and immediately treated to determine the length (L4). The fiber was dried at 60 ℃ for 4 hours, and the fiber length (L5) was measured. Furthermore, drying/water immersion was repeated 3 times, and when the expansion ratio in the filament length direction at the 3 rd time was 50% or more relative to the expansion ratio in the filament length direction at the 1 st time, reversible water swelling properties were exhibited. The expansion ratio in the filament length direction was calculated as follows. Also, the length of the fiber, colored filaments were tied up at two places of the fiber, and the distance therebetween was measured. Bringing the distance to about 100mm.

Expansion ratio in filament length direction (%) = ((L4-L3)/L3) × 100 (%)

Number of crimps V

A fiber sample of 50mm was sampled, and the number of crimp nodes was counted to determine the number of crimp nodes per 25mm, and the number of crimp nodes was determined by multiplying the number by 1/2.

W. color tone (b) ^* Value)

The sample was measured using a color tone meter MINOLTASPACTROPHOTOMETERCM-3700 db ^* The value is obtained. At this time, D is adopted ₆₅ (color temperature 6504K) as a light source, and measured with a 10 ℃ visual field.

Example 1

The melt viscosity was adjusted to 53 pas (262 ℃ C., shear rate 121.6 seconds) ^-1 ) The amine end having a melting point of 220 ℃ was capped with acetic acid, and the amount of amine end groups reached 5.0X 10 ^-5 Molar equivalents/g N6 (20 wt%); and a melt viscosity of 310 pas (262 ℃ C., shear rate 121.6 seconds) ^-1 ) 8 mol% of isophthalic acid having a melting point of 225 ℃ and 4 mol% of bisphenol A were copolymerized to obtain copolymerized PET (80 wt%) having a melting point of 225 ℃ and the resultant was kneaded at 260 ℃ by a twin-screw extruder to obtain b ^* Polymer alloy chip with value = 4. In addition, the copolymerized PET was treated at 262 ℃ for 1216 seconds ^-1 Has a melt viscosity of 180 pas. The mixing conditions at this time were as follows:

2 screws with the same type and type of screw rod and completely engaged in the same direction

Screw diameter 37mm, effective length 1670mm, L/D =45.1

The length of the mixing part is 28 percent of the effective length of the screw

The kneading part is located on the discharge side of the screw than 1/3 of the effective length of the screw

3 reflux parts are arranged in the middle

The polymers were supplied by metering N6 and copolymerized PET, respectively, and supplying them to a kneader.

Temperature: 260 deg.C

And (4) outlet: 2 part (2)

Then, the polymer alloy chips were spun by a spinning machine shown in FIG. 12 to obtain polymer alloy fibers. The polymer alloy chips were fed from a hopper 1, melted in a 275 ℃ melting section 2, and introduced into a rotating block 3 containing a spinning pack 4 having a spinning temperature of 280 ℃. Further, after filtering the polymer alloy melt with a metal nonwoven fabric having an ultrafiltration diameter of 15 μm, melt spinning was carried out from the nozzle 5 whose nozzle face temperature reached 262 ℃. In this case, as shown in FIG. 13, the nozzle 5 has a metering portion 12 having a diameter of 0.3mm at the upper portion of the discharge hole, a discharge hole diameter 14 of 0.7mm and a discharge hole length 13 of 1.75mm. The amount of the single hole injection at this time was 1.0 g/min. At this time, the shear stress between the nozzle hole wall and the polymer was sufficiently low to 0.058MPa (the polymer alloy viscosity was 140 pas, 262 ℃ C., and the shear rate was 416 seconds) ^-1 ). Further, the distance from the lower surface of the nozzle to the cooling start point (the upper end of the gas duct 6) was 9cm. The discharged yarn 7 was cooled and solidified by 20 ℃ cold air for 1m, and after being oiled by an oiling guide 8 provided below the nozzle 51.8m, it was passed through a non-heated 1 st drawing roll 9 and a non-heated 2 nd drawing roll 10 and wound at a winding speed of 900 m/min to obtain 6kg of a wound undrawn yarn package 11. The spinnability was good at this time, and the yarn was broken during 1t of spinning1 time. Then, the undrawn polymer alloy fiber was subjected to a drawing heat treatment by using a drawing apparatus shown in fig. 14. The undrawn yarn 15 is fed by a feed roll 16, and subjected to a drawing heat treatment by a 1 st heating roll 17, a2 nd heating roll 18, and a 3 rd roll 19 to obtain a drawn yarn 20. At this time, the temperature of the 1 st heating roller 17 is 90 ℃ and the temperature of the 2 nd heating roller 18 is 130 ℃. The stretching ratio between the 1 st heating roller 17 and the 2 nd heating roller 18 is 3.2 times. The obtained polymer alloy fiber has the excellent characteristics of 120 dtex, 36 filaments, 4.0cN/dtex strength, 35% elongation, 1.7% U%, and 11% boiling water shrinkage. In addition, the cross section of the obtained polymer alloy fiber is observed by TEMThe results of examination revealed that a sea-island structure (fig. 2) in which the copolymerized PET (thin portion) was sea and the N6 (thick portion) was islands, and a polymer alloy fiber in which the N6 island region had a number average diameter of 53nm and the N6 was uniformly dispersed in a nano-size were obtained.

A circular knitted fabric was produced from the polymer alloy fiber obtained here, and the knitted fabric was immersed in a 3% aqueous sodium hydroxide solution (90 ℃ C., bath ratio 1: 100) for 2 hours, whereby 99% or more of the copolymerized PET in the polymer alloy fiber was hydrolyzed and removed. The resulting circular knitted fabric composed of N6 individual filaments was continuous as long fibers in a macroscopic view, except for the copolymerized PET as a sea component, and maintained the shape of the circular knitted fabric. In addition, the circular knitted fabric is completely different from a circular knitted fabric composed of normal N6 fibers, and the "smooth feeling" peculiar to nylon is lost, and instead, the "rough feeling" like silk or the "dry feeling" like rayon is obtained.

As a result of drawing out the yarn from the circular knitted fabric composed of the N6 individual yarn and observing the fiber side surface with an optical microscope, the fiber diameter was about 2/3 as compared with the fiber before the alkali treatment, and the shrinkage was caused in the fiber radius direction by removing the sea polymer (fig. 4). Next, the observation result of the fiber side surface by SEM showed that the filament was not 1 filament but a nanofiber aggregate in which numerous nanofibers were entangled in the shape of a woven filament (fig. 3). The distance between nanofibers of the N6 nanofiber aggregate is about several nm to several hundred nm, and extremely small voids exist between nanofibers. The observation result of the fiber side surface by TEM is shown in fig. 1, and it is revealed that the single fiber diameter of the N6 nanofiber is about several tens of nm. The number average single fiber diameter of the nanofibers was 56nm (3X 10) ^-5 Decitex) to a fineness not originally present. The single fiber fineness was 1X 10 ^-7 dtex-1X 10 ^-4 The single fiber fineness ratio of dtex (single fiber diameter equivalent to 1 to 105 nm) was 99%. In particular, the single fiber fineness ratio of 55 to 84nm was 71%, and the variation in single fiber fineness was very small. Resolved from TEM photographThe individual fiber diameters and individual fiber fineness histograms of nanofibers are shown in fig. 5 and 6. At this time, the diameter of the single fiber was engraved with 10nm, and the number (frequency) and fineness ratio were counted. When the single fiber diameter is engraved with 10nm, for example, it means that the single fiber diameter is engraved with 55 to 64nmThe diameter of the single fiber is 60nm, and the diameter of the single fiber is 80nm when the single fiber is engraved with the diameter of 75-84 nm.

The results of the moisture absorption rate (Δ MR) measurement of the circular knitted fabric composed of N6 alone showed that the moisture absorption rate exceeded 6% and the moisture absorption property of cotton was extremely excellent. Further, a yarn composed of an N6 nanofiber aggregate was extracted from the circular knitted fabric, and various physical properties were measured. As a result of examining the water-swelling property in the filament length direction, reversible water-absorption swelling/drying shrinkage was repeated (fig. 11). The water-absorption swelling ratio in the filament length direction was 7%, which is a significantly higher value than 3% of the normal N6 fiber. Further, as a result of measuring mechanical properties of the yarn composed of the N6 nanofiber aggregate, the strength was 2.0cN/dtex and the elongation was 50%. Further, the dry heat shrinkage at 140 ℃ was 3%. Further, it is known from the wide-angle X-ray diffraction photograph that the crystal is oriented and crystallized. In addition, the degree of crystal orientation shows a sufficiently high value of 0.85. However, since all the filaments of the nanofiber aggregate extracted from the circular knitted fabric are curled, it is considered that the orientation disorder is favorable, and the actual crystal orientation degree is higher than the measured crystal orientation degree. The Rouland method crystallinity was 55%, and showed a slightly higher value than that of a normal N6 fiber.

The results of polishing the circular knitted fabric showed that the original ultrafine fibers could not provide a superior hand feeling and a quality and texture excellent in moist and body fluid tenderness like human skin.

Example 2

Except that N6 was used in the form of a melt viscosity of 212 pas (262 ℃ C., shear rate of 121.6 seconds) ^-1 ) The amine end group with a melting point of 220 ℃ is blocked by acetic acid, and the amount of the amine end group reaches 5.0 multiplied by 10 ^-5 B was obtained in the same manner as in example 1 except that N6 (20% by weight) was used in a twin-screw extruder and kneader ^* Polymer alloy chip with value = 4. In addition, the discharge amount of each single hole was 1.0 g/min, and the shear stress between the nozzle hole wall and the polymer was 0.071MPa (the viscosity of the polymer alloy was 170 pas, 262 ℃, and the shear rate was 416 seconds) ^-1 ) Except for this, melt spinning was performed in the same manner as in example 1 to obtain a polymer alloy undrawn yarn. The spinnability was good at this time, and the yarn was broken 1 time during 1t of spinning. The polymer alloy fiber obtained by drawing in the same manner as in example 1, except that the undrawn yarn of the polymer alloy fiber had a draw ratio of 3.0 times, had excellent characteristics of 128 dtex, 36 filaments, a strength of 4.1cN/dtex, an elongation of 37%, U% =1.2%, and a boiling water shrinkage of 11%. Further, as a result of TEM observation of the cross section of the obtained polymer alloy fiber, a polymer alloy fiber having a sea-island structure in which the copolymerized PET was sea and the N6 was islands, the number average diameter of the N6 island region was 40nm, and the N6 was uniformly dispersed in a nano size was obtained in the same manner as in example 1.

The polymer alloy fiber obtained here was treated with alkali in the same manner as in example 1 to obtain a nanofiber aggregate in the form of a spun yarn. In addition, the single fiber fineness deviation of these nanofibers was the same as in example1 the number average single fiber diameter of the nanofibers was 43nm (2X 10) ^-5 Dtex) to a fineness that was not present before, and the single fiber fineness deviation is very small.

The circular knitted fabric comprising the nanofiber aggregate had a moisture absorption rate (Δ MR) of 6% and a water swelling rate in the filament length direction of 7%. The yarn composed of the nanofiber aggregate had a strength of 2.2cN/dtex and an elongation of 50%. Further, the dry heat shrinkage at 140 ℃ was 3%.

Example 3

Except that N6 was used with a melt viscosity of 500Pa DEGs (262 ℃, shear rate 121.6 seconds) ^-1 ) Melt spinning was carried out in the same manner as in example 2 except that the melting point was changed to 220 ℃ and N6 (20% by weight). Then, except that the shear stress between the nozzle hole wall and the polymer was 0.083MPa (polymer alloy viscosity: 200 pas, 262 ℃, 416 seconds) ^-1 ) Except for this, the same melt spinning as in example 1 was carried out to obtain a polymer alloy undrawn yarn. The spinnability was good at this time, and the yarn was broken 1 time during 1t of spinning. The obtained polymer alloy fiber was drawn and heat-treated in the same manner as in example 2, and had excellent properties of 128 dtex, 36 filaments, a strength of 4.5cN/dtex, an elongation of 37%, U% =1.9%, and a boiling water shrinkage of 12%. The TEM observation of the cross section of the obtained polymer alloy fiber revealed that a polymer alloy fiber having a sea-island structure in which the copolymerized PET was sea and N6 was islands, the number average diameter of the N6 island region was 60nm, and N6 was uniformly dispersed in a nano size was obtained in the same manner as in example 1.

The polymer alloy fiber obtained here was treated with alkali in the same manner as in example 1 to obtain a nanofiber aggregate in the form of a spun yarn. Further, as a result of analyzing the variation in the single fiber fineness of these nanofibers in the same manner as in example 1, the number average single fiber diameter of the nanofibers was 65nm (4 × 10) ^-5 Dtex) to achieve the fineness which is not available originally, and the single fiber fineness deviation is very small.

The circular knitted fabric comprising the nanofiber aggregate had a moisture absorption rate (Δ MR) of 6% and a water absorption swelling rate in the filament length direction of 7%. The filament composed of the nanofiber aggregate had a strength of 2.4cN/dtex and an elongation of 50%. Further, the dry heat shrinkage at 140 ℃ was 3%.

Example 4

Melt spinning was performed in the same manner as in example 3, except that the mixing ratio of N6 was 50% by weight of the entire polymer alloy. Then, melt spinning was carried out in the same manner as in example 3 except that the shear stress between the nozzle hole wall and the polymer was 0.042MPa, to obtain a polymer alloy undrawn yarn. The spinnability was good at this time, and the yarn was broken 1 time during 1t of spinning. The polymer alloy fiber obtained by drawing and heat treatment in the same manner as in example 3 had excellent properties of 128 dtex, 36 filaments, strength of 4.53cN/dtex, elongation of 37%, U% =2.5%, and boiling water shrinkage of 13%. The TEM observation of the cross section of the obtained polymer alloy fiber revealed that a polymer alloy fiber having a sea-island structure in which the copolymerized PET was sea and the N6 was islands, the number average diameter of the N6 island region was 80nm, and the N6 was uniformly dispersed in a nano size was obtained in the same manner as in example 1.

The polymer alloy fiber obtained here was treated with alkali in the same manner as in example 1 to obtain a nanofiber aggregate in the form of a spun yarn. Further, as a result of analyzing the variation in the single fiber fineness of these nanofibers in the same manner as in example 1, the number average single fiber diameter of the nanofibers was 84nm (6X 10) ^-5 Dtex) to a fineness that was not present before, and the single fiber fineness deviation is very small.

The yarn composed of the N6 nanofiber aggregate had a strength of 2.6cN/dtex and an elongation of 50%.

Comparative example 1

The melt viscosity was 180 pas (290 ℃ C., shear rate 121.6 seconds) ^-1 ) PET having a melting point of 255 ℃ as an island component and a melt viscosity of 100 pas (290 ℃ C., shear rate of 121.6 seconds) ^-1 ) And Polyethylene (PS) having a Vickers softening temperature of 107 ℃ as a sea component, and a sea-island composite yarn was obtained by the method described in example 1 of Japanese patent application laid-open No. 53-106872. Then, the resultant was treated with trichloroethylene by the method described in the example of Japanese patent application laid-open No. 53-106872, to remove 99% or more of PS, thereby obtaining a super filament. The cross section of the obtained fiber was observed by TEM and it was revealed that the filament diameter of the ultrafine filament was as large as 2.0 μm (0.04 dtex).

Comparative example 2

Except that the melt viscosity was 50 pas (280 ℃ C., 121.6 seconds) ^-1 ) N6 having a melting point of 220 ℃ and a melt viscosity of 210 pas (280 ℃ C., 121.6 seconds) ^-1 ) PET having a melting point of 255 ℃ was sliced and mixed so that the mixing ratio of N6 reached 20% by weight, and then the mixture was melted at 290 ℃ and melt-spun at a spinning temperature of 296 ℃ and a nozzle surface temperature of 280 ℃ in the same manner as in example 1 except that a short-tube nozzle having a nozzle hole number of 36, a discharge hole diameter of 0.30mm and a discharge hole length of 0.50mm was used, and undrawn yarn was taken up at a spinning speed of 1000 m/min.Since the melting point difference between the polymers was large due to the simple chip mixing, the mixing unevenness of N6 and PET was large, large edge scum was generated under the nozzle, and the drawability was poor, and it was impossible to stably wind the yarn and obtain a small amount of undrawn yarn, and the temperature of the 1 st heat roll 17 was 85 ℃ and the drawing ratio was 3 times, and the drawing was carried out in the same manner as in example 1 to obtain drawn yarns of 100 dtex and 36 filaments.

Using this yarn, a circular knitted fabric was produced in the same manner as in example 1, and treated with alkali in the same manner to remove 99% or more of the PET component. The N6 single filaments were drawn out from the circular knitted fabric, and the fiber cross section was observed by TEM to show that the single fiber diameter was 400nm to 4 μm (single fiber fineness 1X 10) ^-3 ～ 1×10 ^-1 Dtex). However, the number average single fiber fineness thereof was as large as 9X 10 ^-3 Dtex (single fiber diameter 1.0 μm). Further, the single fiber fineness variation of the N6 ultrafine filament was large.

Comparative example 3

Except that the melt viscosity of 395 Pa.s (262 ℃,121.6 seconds) was used ^-1 ) N6 having a melting point of 220 ℃ and a melt viscosity of 56 pas (262 ℃,121.6 seconds) ^-1 ) And PE having a melting point of 105 ℃ were sliced and mixed so that the mixing ratio of N6 reached 65% by weight, and then melted at 260 ℃ by a single-shaft extrusion kneader 21 using the apparatus shown in FIG. 15, and then melt-spun in the same manner as in example 1 except that the melt-spun yarn was formed using a short-tube nozzle having a nozzle hole number of 12, a discharge hole diameter of 0.30mm, and a discharge hole length of 0.50 mm. The mixed spot of N6 and PE is large, large side slag is generated under a nozzle, and the wire is drawnThe drawn yarn was inferior in properties and could not be stably taken up, and a small amount of undrawn yarn was obtained, and drawn and heat-treated in the same manner as in example 1 to obtain a drawn yarn of 82 dtex and 12 filaments. The draw ratio in this case was 2.0 times.

Using this yarn, a circular knitted fabric was produced in the same manner as in example 1, and PE was eluted with toluene at 85 ℃ for 1 hour or more to remove 99% or more of the PE component. The N6 monofilaments were pulled out of the resulting circular knitted fabric and the fiber cross-section was observed by TEM to show that the produced monofilaments had a diameter of 500nm to 3 μm (single-fiber fineness: 2X 10) ^-3 ～8×10 ^-2 Dtex). The average single fiber fineness is as large as 9X 10 ^-3 Dtex (single fiber diameter 1.0 μm). Further, the variation in the single fiber fineness of the N6 ultrafine filament is large.

Comparative example 4

Except that the melt viscosity was 150 pas (262 ℃ C., 121.6 seconds) ^-1 ) N6 having a melting point of 220 ℃ and a melt viscosity of 145 pas (262 ℃,121.6 seconds) ^-1 ) PE having a melting point of 105 ℃ was sliced and mixed so that the mixing ratio of N6 became 20% by weight, and then the polymer was separately metered and introduced into biaxial extrusion kneadingMelt spinning was carried out in the same manner as in comparative example 3 using the apparatus shown in FIG. 17. However, the mixed unevenness of N6 and PE was large, large edge scum was generated under the nozzle, the drawability was poor, the yarn could not be stably wound, a small amount of undrawn yarn was obtained, and the drawn yarn was drawn and heat-treated in the same manner as in example 1 to obtain 82 dtex and 12 filaments. The draw ratio in this case was 2.0 times.

Using the yarn, a circular knitted fabric was produced in the same manner as in example 1, and PE was eluted with toluene at 85 ℃ for 1 hour or more to remove 99% or more of the PE component. The N6 monofilaments were pulled out of the resulting circular knitted fabric and the fiber cross-section was observed by TEM to show that the single-fiber diameter was 100nm to 1 μm (single-fiber fineness 9X 10) ^-5 ～9×10 ^-3 Dtex). However, the number average single fiber fineness thereof is as large as 1X 10 ^-3 Dtex (single fiber diameter 384 nm). In addition, the N6-type peptide isThe single fiber fineness deviation of the very fine yarn was large (fig. 7 and 8).

Comparative example 5

A sea-island composite yarn was produced by the method described in comparative example 1 of Japanese patent publication No. 60-28922 using the spinning pack and nozzle described in FIG. 11 of this publication and using PS and PET described in comparative example 1 of this publication. In this case, the island component of the sea-island composite yarn is a 2: 1 (weight ratio) mixed polymer of PS and PET, and PS is used as the sea component. The sea-island composite ratio is 1: 1 by weight. Specifically, in FIG. 11, the component A is PET, and the components B and C are PS. Further, the yarn was treated with trichloroethylene in the same manner as described in comparative example 1 of the above publication to remove 99% or more of PS, thereby obtaining a super oiled yarn. As a result of observing the cross section of the fiber of the super oiled yarn, although a very small amount of single fibers having a minimum single fiber diameter of about 100nm were present, the dispersion of PET in PS was deteriorated, and the number average single fiber diameter was as large as 9X 10 ^-4 Dtex (single fiber diameter 326 nm) and large variation in single fiber fineness of the ultrafine filament (fig. 9 and 10).

TABLE 1

	Island polymers			Sea polymers			Jet hole Cutting material Force of (MPa)
	Island polymers			Sea polymers				Polymer and method of making same	Melt viscosity Degree of rotation (Pa·s)	Ratio of (wt％)	Polymer and method of making same	Melt viscosity Degree of rotation (Pa·s)	Ratio of (wt％)
	Example 1 Example 2 Example 3 Example 4	N6 N6 N6 N6	53 212 500 500	20 20 20 50	Copolymerization of olefins PET Copolymerization of PET Copolymerization of PET Copolymerization of PET	310 310 310 310		Polymer and method of making same	Melt viscosity Degree of rotation (Pa·s)	Ratio of (wt％)	Polymer and method of making same	Melt viscosity Degree of rotation (Pa·s)	Ratio of (wt％)	80 80 80 50	0.058 0.071 0.083 0.042
Comparative example 1 Comparative example 2 Comparative example 3 Comparative example 4 Comparative example 5	Example 1 Example 2 Example 3 Example 4	N6 N6 N6 N6	53 212 500 500	20 20 20 50		310 310 310 310	PET N6 N6 N6 PS/PET	180 50 395 150 -	96 20 65 20 50	PS PET PE PE PS	100 210 56 145 -	4 80 35 80 50	- 0.41 0.64 0.40 -	80 80 80 50	0.058 0.071 0.083 0.042

TABLE 2

	Island region Number average diameter (nm)	Deviation of island region		Strength of (cN/dtex)	U％ (％)
		Deviation of island region				Ratio of dough distribution (％)	Range Diameter range: area ratio
		Example 1 Example 2 Example 3 Example 4	53 40 60 80			Ratio of dough distribution (％)	Range Diameter range: area ratio	100 100 99 85	45～74nm：72％ 35～64nm：75％ 55～84nm：70％ 65～94nm：66％	4.0 4.1 4.5 4.3	1.7 1.2 1.9 2.5
Less than comparative example 1 Comparative example 2 Comparative example 3 Comparative example 4 Comparative example 5	2000 1000 1000 374 316	Example 1 Example 2 Example 3 Example 4	53 40 60 80	0 0 0 0 0	- 974～1005nm：10％ 974～1005nm：10％ 395～424nm：10％ 395～424nm：10％	- - - - -	- 23.5 22.7 20.3 17.3	100 100 99 85	45～74nm：72％ 35～64nm：75％ 55～84nm：70％ 65～94nm：66％	4.0 4.1 4.5 4.3	1.7 1.2 1.9 2.5

Area ratio: the island region has an area ratio of 1 to 100nm in diameter

The range is as follows: the area ratio between the diameter differences of 30 nm.

TABLE 3

	Number average of nanofibers		Deviation of nanofiber		Nano-fiber Strength of (cN/dtex)
	Number average of nanofibers		Deviation of nanofiber			Diameter of (nm)	Fineness of fiber (dtex)	Fineness ratio (％)	Range Diameter range: fineness ratio
	Example 1 Example 2 Example 3 Example 4	56 43 65 84	3×10 ^-5 2×10 ^-5 4×10 ^-5 6×10 ^-5	99 100 98 78		Diameter of (nm)	Fineness of fiber (dtex)	Fineness ratio (％)	Range Diameter range: fineness ratio	55～84nm：71％ 45～74nm：75％ 65～94nm：70％ 75～104nm：64％	2.0 2.2 2.4 2.6
Comparative example 1 Comparative example 2 Comparative example 3 Comparative example 4 Comparative example 5	Example 1 Example 2 Example 3 Example 4	56 43 65 84	3×10 ^-5 2×10 ^-5 4×10 ^-5 6×10 ^-5	99 100 98 78	2000 1000 1000 384 326	4×10 ^-2 9×10 ^-3 9×10 ^-3 1×10 ^-3 9×10 ^-4	0 0 0 0 0	- 974～1005nm：10％ 974～1005nm：10％ 395～424nm：10％ 395～424nm：10％	- - - - -	55～84nm：71％ 45～74nm：75％ 65～94nm：70％ 75～104nm：64％	2.0 2.2 2.4 2.6

Fineness ratio: single filament fineness is 1X 10 ^-7 ～1×10 ^-4 Fineness ratio in decitex range

The range is as follows: at a titer ratio between 30nm in diameter difference.

Example 5

N6 and the copolymerized PET used in example 1 were melted at 270 ℃ by using the apparatus shown in FIG. 16, and the polymer melt was introduced into a rotating block 3 having a spinning temperature of 280 ℃. Then, the 2 polymers were divided into 104 thousands by the static kneader 22 (ハィミキサ manufactured by east レェンジニァリング) installed in the spinning pack 4, and sufficiently mixed, followed by melt spinning in the same manner as in example 1. The polymer mixing ratio N6 was 20% by weight, the copolymerized PET was 80% by weight, and the shear stress of the nozzle was 0.060MPa. The spinnability was good, and the yarn was broken 1 time during 1t of spinning. The undrawn yarn was also drawn and heat-treated in the same manner as in example 1. The obtained polymer alloy fiber has the excellent characteristics of 120 dtex, 36 filaments, 3.9cN/dtex strength, 38% elongation, 1.7% U%, and 11% boiling water shrinkage. The results of TEM observation of the cross section of the polymer alloy fiber revealed that, in the same manner as in example 1, a polymer alloy fiber having a sea-island structure in which the copolymerized PET was sea and the N6 was islands, the number average diameter of the N6 island region was 52nm, and the N6 was uniformly dispersed in a nano-size was obtained.

Using the polymer alloy fibers obtained here, a nanofiber aggregate in the form of a spun yarn was obtained by alkali treatment in the same manner as in example 1A body. Further, as a result of analyzing the variation in the single fiber fineness of these nanofibers in the same manner as in example 1, the number average single fiber diameter of the nanofibers was 54nm (3X 10) ^-5 Dtex) to a fineness that was not present before, and the single fiber fineness deviation is very small.

The circular knitted fabric comprising the nanofiber aggregate had a moisture absorption rate (Δ MR) of 6% and a water absorption swelling rate in the filament length direction of 7%. The filament composed of the nanofiber aggregate had a strength of 2.0cN/dtex and an elongation of 50%. Further, the dry heat shrinkage at 140 ℃ was 3%.

The results of polishing the circular knitted fabric showed that the original ultra-fine fibers had a quality and texture that was not superior in the super touch and the delicate touch of body fluids such as human skin.

Example 6

Melt spinning was carried out in the same manner as in example 1 except that N6 and copolymerized PET used in example 4 were used and the mixing ratio of N6 and copolymerized PET was 80 wt%/20 wt%, to prepare precursor pellets. The precursor pellets and N6 fresh pellets used for melt kneading were charged into a hopper 1 by the apparatus shown in FIG. 17, and were independently measured by a measuring section 24 and supplied to a mixing tank 25 (capacity 7 kg). At this time, the mixing ratio of the precursor pellets and the N6 fresh pellets was 1: 1 by weight, and an antistatic agent (ェマルミン (registered trademark) 40, manufactured by Sanyo chemical industries, ltd.) for preventing the pellets from adhering to the wall surface of the mixing tank was contained in an amount of 20ppm. Then, the pellets were stirred in the mixing tank and then supplied to a twin-screw extruder 23 to prepare a polymer alloy having a molten and kneaded N6 content of 40 wt%. At this time, the kneading section length was 33% of the effective screw length, and the kneading temperature was 270 ℃. The polymer melt was then introduced into a rotating block 3 at a spinning temperature of 280 ℃. Melt spinning was performed in the same manner as in example 4. The undrawn yarn was also drawn and heat-treated in the same manner as in example 4. The obtained polymer alloy fiber has the excellent characteristics of 120 dtex, 36 filaments, 3.0cN/dtex strength, 30% elongation and 3.7% U%. The results of TEM observation of the cross section of the polymer alloy fiber showed that, in the same manner as in example 1, the copolymerized PET was sea, N6 was island-sea structure, and the number average diameter of the N6 island region was 110nm, which was slightly larger than the single fiber fineness of the nanofiber and had large variation.

The polymer alloy fiber obtained here was treated with alkali in the same manner as in example 4 to obtain a nanofiber aggregate in the form of a spun yarn. Further, as a result of analyzing the variation in the single fiber fineness of these nanofibers in the same manner as in example 1, the number average single fiber diameter of the nanofibers was 120nm (1.3X 10) ^-4 Dtex) was observed, and the single fiber fineness was large and the variation in single fiber fineness was large as compared with example 4.

The circular knitted fabric comprising the nanofiber aggregate had a moisture absorption rate (Δ MR) of 5% and a water absorption swelling rate in the filament length direction of 7%. The yarn composed of the N6 nanofiber aggregate had a strength of 1.2cN/dtex and an elongation of 50%. Further, the dry heat shrinkage at 140 ℃ was 3%.

TABLE 4

Island polymers			Sea polymers			Kneading Sequence of events	Jet hole Shear force (MPa)
Island polymers			Sea polymers					Polymer and method of making same	Melt viscosity Degree of rotation (Pa·s)	Ratio of (wt％)	Polymer and method of making same	Melt viscosity Degree of rotation (Pa·s)	Than (wt％)
Example 5 Example 6	N6 N6	53 500	20 40	Copolymerization of olefins PET Copolymerization of PET	310 310			Polymer and method of making same	Melt viscosity Degree of rotation (Pa·s)	Ratio of (wt％)	Polymer and method of making same	Melt viscosity Degree of rotation (Pa·s)	Than (wt％)	80 60	Spinning Assembly Inner part Spinning Assembly Front side	0.060 0.20

TABLE 5

Island region Number average diameter (nm)	Deviation of island area		Strength of (cN/dtex)	U％ (％)
	Deviation of island area				Area ratio (％)	Range Diameter range: area ratio
	Example 5 Example 6	52 110			Area ratio (％)	Range Diameter range: area ratio	100 60 ^*	45～74nm：72％ 95～124nm：50％	3.9 3.0	1.7 3.7

Area ratio: the island region diameter is in the range of 1-100 nm

^* : the island region diameter is in the range of 1-150 nm

The range is as follows: at an area ratio between 30nm of diameter difference.

TABLE 6

Number average of nanofibers		Deviation of nanofiber		Nano-fiber Intensity (cN/dtex)
Number average of nanofibers		Deviation of nanofiber			Diameter of (nm)	Fineness of fiber (dtex)	Fineness ratio (％)	Range Diameter range: fineness ratio
Example 5 Example 6	54 120	3×10 ^-5 1.3×10 ^-4	99 95 ^*		Diameter of (nm)	Fineness of fiber (dtex)	Fineness ratio (％)	Range Diameter range: fineness ratio	55～84nm：72％ 105～134nm：50％	2.0 1.2

^* : single filament fineness is 1X 10 ^-7 ～2×10 ^-4 Fineness ratio in decitex range

The range is as follows: the titer ratio between the diameter differences of 30 nm.

Example 7

Except that the hot water-soluble polymer "パォゲン (registered)Trade mark) PP-15 "(melt viscosity 350 pas, 262 ℃ C., 121.6 seconds ^-1 Melting Point 55 ℃ C.) instead of copolymerized PET, kneading and melt spinning were carried out in a spin pack using the same static kneader as in example 5 except that the spinning speed was 5000 m/min. The "パォゲン (registered trademark) PP-15" was treated at 262 ℃ for 1216 seconds ^-1 Has a melt viscosity of 180 pas. The obtained polymer alloy fiber has the excellent characteristics of 70 dtex, 12 filaments, 3.8cN/dtex strength, 30% elongation and 1.7% U%. The TEM observation of the cross section of the polymer alloy fiber revealed that a polymer alloy fiber having a sea-island structure in which the copolymerized PET was sea and N6 was islands, the number average diameter of the N6 island region was 53nm, and N6 nanofibers were uniformly dispersed was obtained.

The polymer alloy fiber obtained here was treated with alkali in the same manner as in example 1 to obtain a nanofiber aggregate in the form of a spun yarn. In addition, theThe number average single fiber diameter of the nanofibers was 56nm (3X 10) as a result of analyzing the single fiber fineness variation of these nanofibers in the same manner as in example 1 ^-5 Dtex) to a fineness that was not present before, and the single fiber fineness deviation is also very small.

The circular knitted fabric comprising the nanofiber aggregate had a moisture absorption rate (Δ MR) of 6% and a water absorption swelling rate in the filament length direction of 7%. The yarn composed of the N6 nanofiber aggregate had a strength of 2.0cN/dtex and an elongation of 60%.

The result of polishing the circular knitted fabric shows that the circular knitted fabric has a superior hand feeling that cannot be obtained by the original ultra-fine fiber and a quality texture that is excellent in moist feeling like human skin.

Example 8

Except that the melt viscosity was changed to 100 pas (280 ℃ C., 121.6 seconds) ^-1 ) N66 having a melting point of 250 ℃ was used in place of N6, and the hot-water-soluble polymer used in example 7 was used in place of copolymerized PET, and the melt of N66 was melted at 270 ℃ and 80 ℃ using an apparatus shown in FIG. 16, and then introduced into a rotating block 3 having a spinning temperature of 280 ℃. Melt spinning was performed in the same manner as in example 5. In this case, the mixing ratio N66 of the polymer was 20% by weight, the hot-water-soluble polymer was 80% by weight, and the single-hole discharge amount was 1.0 g/min. The spinning speed at this time was 5000 m/min. The polymer alloy fiber with 70 dtex, 12 filaments, 4.5cN/dtex strength and 45% elongation is obtained. The cross section of the polymer alloy fiber is observed by TEM, and the polymer alloy fiber is obtained, wherein the hot water soluble polymer is a sea, N66 is a sea island structure of islands, the number average diameter of an N66 island region is 58nm, and N66 nano fibers are uniformly dispersed.

Using the polymer alloy fiber obtained here, a textile fabric was obtained by alkali treatment in the same manner as in example 1A nanofiber aggregate in a filament shape. Further, as a result of analyzing the variation in the single fiber fineness of these nanofibers in the same manner as in example 1, the number average single fiber of the nanofibers wasDimension diameter of 62nm (3X 10) ^-5 Dtex) to a fineness that was not present before, and the single fiber fineness deviation is also very small.

The circular knitted fabric comprising the nanofiber aggregate had a moisture absorption rate (Δ MR) of 6% and a water absorption swelling rate in the filament length direction of 7%. The yarn composed of the N66 nanofiber aggregate had a strength of 2.5cN/dtex and an elongation of 60%.

Example 9

Except that the melt viscosity was changed to 300 pas (262 ℃ C., 121.6 seconds) ^-1 ) And a copolymerized PET having a melting point of 235 ℃ (8 wt% PEG1000, 7 mol% isophthalic acid copolymerized) were kneaded and melt-spun with the hot water-soluble polymer in the same manner as in example 8, except that N66 was replaced with the copolymerized PET. In this case, the mixing ratio of the polymer was 20% by weight of the copolymerized PET and 80% by weight of the hot-water-soluble polymer, and the ejection amount per one hole was 1.0 g/min. The spinning speed at this time was 6000 m/min. The shear stress between the nozzle hole wall and the polymer at this time was sufficiently low to 0.11MPa. The obtained polymer alloy fiber has 60 dtex, 36 filaments, 3.0cN/dtex strength and 55% elongation. The TEM observation of the cross section of the obtained polymer alloy fiber revealed that a sea-island structure in which the hot-water-soluble polymer was sea and the copolymerized PET was islands was obtained, and that the number-average diameter of the copolymerized PET island region was 52nm, and the copolymerized PET nanofibers were uniformly dispersed.

Using the polymer alloy fibers obtained here, circular knitted fabrics were produced in the same manner as in example 1, and the hot-water-soluble polymer was dissolved in hot water at 100 ℃ to obtain circular knitted fabrics composed of nanofiber aggregates having a "rough feel" like silk fabrics or a "dry feel" like rayon. Further, as a result of analyzing the variation in the single fiber fineness of these nanofibers in the same manner as in example 1, the number average single fiber diameter of the nanofibersIs 54nm (3X 10) ^-5 Dtex) to a fineness which has not been achieved before, and the single fiber fineness deviation is also very small.

The circular knitted fabric comprising the nanofiber aggregate had a moisture absorption rate (Δ MR) of 2%. The yarn composed of the copolymerized PET nanofiber aggregate had a tenacity of 2.0cN/dtex and an elongation of 70%.

Example 10

Except that the melt viscosity was 190 pas (280 ℃ C., 121.6 seconds) ^-1 ) And PET having a melting point of 255 ℃ in place of the copolymerized PET, kneading and melt spinning were carried out in the same manner as in example 9. In this case, the mixing ratio of the polymer was 20 wt% for PET, 80 wt% for hot-water-soluble polymer, 285 ℃ for PET, 80 ℃ for hot-water-soluble polymer, and 1.0 g/min for single-hole discharge. The shear stress between the nozzle hole wall and the polymer at this time was sufficiently low to 0.12MPa. The obtained polymer alloy fiber has 60 dtex, 36 filaments, 3.0cN/dtex strength and 45% elongation. The TEM observation of the cross section of the polymer alloy fiber revealed that a polymer alloy fiber having a sea-island structure in which the hot-water-soluble polymer was sea and the PET was islands, the number average diameter of the PET island region was 62nm, and the PET nanofibers were uniformly dispersed was obtained.

Using the polymer alloy fibers obtained here, a nanofiber assembly was produced in the same manner as in example 9. The number average single fiber diameter of the nanofiber was 65nm (3X 10) ^-5 Dtex) to the original fineness and the single fiber fineness deviation is very small.

Example 11

Except that the melt viscosity was changed to 120 pas (262 ℃ C., 121.6 seconds) ^-1 ) And PBT having a melting point of 225 ℃ was kneaded and melt-spun in the same manner as in example 9, except that the copolymerized PET was replaced by PBT. In this case, the mixing ratio of the polymer was 20% by weight of PBT, 80% by weight of the hot-water-soluble polymer, 255% by weight of PBT, 80% by weight of PBT, 265% by weight of PBT and 1.0 g/min of PBT having a single-hole discharge rate. At this timeThe shear stress between the nozzle orifice wall and the polymer is sufficiently low to 0.12MPa. The obtained polymer alloy fiber has 60 dtex, 36 filaments, strength of 3.0cN/dtex and elongation of 45%. The cross section of the polymer alloy fiber is observed by TEM, and the polymer alloy fiber is obtained, wherein the hot water soluble polymer is sea, the PBT is island structure, the number average diameter of the PBT island region is 62nm, and the PBT nano fiber is uniformly dispersed.

Using the polymer alloy fibers obtained here, a nanofiber assembly was produced in the same manner as in example 9. The number average single fiber diameter of the nanofiber was 65nm (4X 10) ^-5 Dtex) to achieve the original fineness, and the single fiber fineness deviation is very small.

Example 12

Except that the melt viscosity was changed to 220 pas (262 ℃ C., 121.6 seconds) ^-1 ) PTT replacement of melting point 225 ℃Kneading and melt spinning were carried out in the same manner as in example 9 except that PET was copolymerized. At this time, the shear stress between the nozzle hole wall and the polymer was sufficiently low to 0.13MPa. The obtained polymer alloy fiber has 60 dtex, 36 filaments, 3.0cN/dtex strength and 45% elongation. The TEM observation of the cross section of the polymer alloy fiber shows that the obtained hot water soluble polymer is sea-island structure with sea and PTT as islands, the number average diameter of the PTT island region is 62nm, and the PTT nano-fiber is uniformly dispersed.

Using the polymer alloy fibers obtained here, a nanofiber assembly was produced in the same manner as in example 9. The number average single fiber diameter of the nanofiber was 65nm (4X 10) ^-5 Dtex) to the original fineness and the single fiber fineness deviation is very small.

Example 13

Except that the melt viscosity was changed to 350 pas (220 ℃ C., 121.6 seconds) ^-1 ) Kneading and melt spinning were carried out in the same manner as in example 9 except that PLA having a melting point of 170 ℃ was used instead of copolymerized PET. In this case, the mixing ratio of the polymer is 20% by weight of PLA and 80% by weight of the hot-water-soluble polymer,the spinning temperature was 235 ℃, the nozzle face temperature was 220 ℃, and the single-hole discharge amount was 1.0 g/min. The obtained polymer alloy fiber has 60 dtex, 36 filaments, strength of 2.5cN/dtex and elongation of 35%. The cross section of the polymer alloy fiber is observed by TEM, and the polymer alloy fiber is obtained, wherein the hot water soluble polymer is sea, PLA is island structure, the number average diameter of PL4 island region is 48nm, and the PLA nano fiber is uniformly dispersed.

Using the polymer alloy fibers obtained here, a nanofiber assembly was produced in the same manner as in example 9. The number average single fiber diameter of the nanofiber was 50nm (2X 10) ^-5 Dtex) to achieve the original fineness, and the single fiber fineness deviation is very small.

TABLE 7

Island polymers			Sea polymers			Mixing sequence
Island polymers			Sea polymers				Polymer and method of making same	Melt viscosity Degree of rotation (Pa·s)	Ratio of (wt％)	Polymer and method of making same	Melt viscosity Degree of rotation (Pa·s)	Ratio of (wt％)
Example 7 Example 8 Example 9 Example 10 Example 11 Example 12 Example 13	N6 N66 Copolymerized PET PET PBT PTT PLA	53 100 300 190 120 220 350	20 20 20 20 20 20 20	Water soluble in Hot Water Polymer and process for producing the same Water soluble in Hot Water Polymer and method of making same Soluble in hot water Polymer and method of making same Water soluble in Hot Water Polymer and method of making same Water soluble in Hot Water Polymer and method of making same Water soluble in Hot Water Polymer and method of making same Water soluble in Hot Water Polymer and process for producing the same	350 220 350 220 350 350 600		Polymer and method of making same	Melt viscosity Degree of rotation (Pa·s)	Ratio of (wt％)	Polymer and method of making same	Melt viscosity Degree of rotation (Pa·s)	Ratio of (wt％)	80 80 80 80 80 80 80	Spinning assembly Inner part Spinning assembly Inner part Spinning assembly Inner part Spinning assembly Inner part Spinning assembly Inner part Spinning assembly Inner part Spinning assembly Inner part

TABLE 8

Island region Number average diameter (nm)	Island regional deviation		Strength of (cN/dtex)	U％ (％)
	Island regional deviation				Area ratio (％)	Scope is Diameter range: area ratio
	Example 7 Example 8 Example 9 Example 10 Example 11 Example 12 Example 13	53 58 52 62 62 62 48			Area ratio (％)	Scope is Diameter range: area ratio	100 100 100 97 98 98 100	45～74nm：72％ 55～84nm：70％ 45～74nm：72％ 55～84nm：65％ 55～84nm：68％ 55～84nm：65％ 45～74nm：75％	3.8 4.5 3.0 3.0 3.0 3.0 2.5	1.7 1.7 1.6 2.3 2.0 2.0 1.2

Area ratio: the island region has an area ratio of 1 to 100nm in diameter

The range is as follows: at an area ratio between 30nm of diameter difference.

TABLE 9

Number average of nanofibers		Deviation of nanofiber		Nano-fiber Strength of (cN/dtex)
Number average of nanofibers		Deviation of nanofiber			Diameter of (nm)	Fineness of fiber (dtex)	Fineness ratio (％)	Range Diameter range: fineness ratio
Example 7 Example 8 Example 9 Example 10 Example 11 Example 12 Example 13	56 62 54 65 65 65 50	3×10 ^-5 3×10 ^-5 3×10 ^-5 5×10 ^-5 4×10 ^-6 4×10 ^-5 2×10 ^-4	99 98 99 98 98 98 100		Diameter of (nm)	Fineness of fiber (dtex)	Fineness ratio (％)	Range Diameter range: fineness ratio	55～84nn：72％ 55～84nm：68％ 55～84nm：71％ 55～84nm：65％ 55～84nm：65％ 55～84nm：65％ 45～74nm：72％	2.0 2.5 2.0 2.0 2.0 2.0 1.9

The range is as follows: at a titer ratio between 30nm in diameter difference.

Example 14

Except that the melt viscosity was changed to 300 pas (262 ℃ C., 121.6 seconds) ^-1 ) Kneading and melt spinning were carried out in the same manner as in example 8 except that N66 was replaced by Polycarbonate (PC) having a heat distortion temperature of 140 ℃. At this time, the mixing ratio PC of the polymer was 20% by weight, the hot-water-soluble polymer was 80% by weight, and the single-hole ejection amount was 1.0 g/min. The polymer alloy fiber with 70 dtex, 36 filaments, strength of 2.2cN/dtex and elongation of 35% is obtained. The TEM observation of the cross section of the polymer alloy fiber shows that the hot water-soluble polymer is a sea-island structure with sea and PC islands, the number average diameter of the PC island region is 85nm, and the PC nanofibers are uniformly dispersed.

Using the polymer alloy fibers obtained here, a circular knitted fabric was produced in the same manner as in example 1, and then treated with hot water at 40 ℃ for 10 hours to elute 99% or more of a hot-water-soluble polymer, thereby obtaining a nanofiber aggregate. The number average single fiber diameter of the nanofiber was 88nm (8X 10) ^-5 Dtex) to a fineness that was not present before, and the single fiber fineness deviation is also very small.

Example 15

Except that the melt viscosity was changed to 300 pas (262 ℃ C., 121.6 seconds) ^-1 ) Polymethyl methacrylate having a melting point of 220 ℃Limonene (PMP) and melt viscosity 300 Pa.s (262 ℃,121.6 sec) ^-1 ) And a Vickers softening temperature of 105 ℃ was set in place of N6 and PET, and kneading and melt spinning were carried out in the same manner as in example 8 except that the spinning speed was 1500 m/min. Then, stretching and heat treatment were carried out in the same manner as in example 1 at a stretch ratio of 1.5. At this time, the process of the present invention,the mixing ratio of the polymer was 20 wt% of PMP, 80 wt% of PS, and 1.0 g/min of single hole injection amount. A polymer alloy fiber having 77 dtex, 36 filaments, a strength of 3.0cN/dtex, an elongation of 40% is obtained. The cross section of the polymer alloy fiber is observed by a TEM (transmission electron microscope) to show that the polymer alloy fiber is obtained, wherein PS is sea, PMP is island-in-sea structure, the number average diameter of PMP island region is 70nm, and PMP nano-fiber is uniformly dispersed.

Using the polymer alloy fibers obtained here, a circular braid was produced in the same manner as in example 1. The PS was embrittled with concentrated hydrochloric acid at 40 ℃ and then removed with methyl ethyl ketone to obtain a circular knitted fabric comprising a PMP nanofiber aggregate. The number average single fiber diameter of the nanofibers was 73nm (5X 10) ^-5 Dtex) to a fineness that was not present before, and the single fiber fineness deviation is also very small.

Example 16

Except that the melt viscosity was 300 pas (220 ℃ C., 121.6 seconds) ^-1 ) PP having a melting point of 162 ℃ and the hot-water-soluble polymer used in example 7 were kneaded, melt-spun, drawn, and heat-treated in the same manner as in example 15, except that PMP and PS were replaced. At this time, the mixing ratio PP of the polymer was 20% by weight, the hot water-soluble polymer was 80% by weight, the spinning temperature was 235 ℃, the nozzle face temperature was 220 ℃, and the single hole discharge amount was 1.0 g/min. A polymer alloy fiber having 77 dtex, 36 filaments, a strength of 2.5cN/dtex, and an elongation of 50% was obtained. The cross section of the obtained polymer alloy fiber was observed by TEM, and it was revealed that the hot water-soluble polymer was sea, PP was island-sea structure of islands, the number average diameter of the PP island region was 48nm, and the PP nanofibers were uniformly dispersed.

Using the polymerization obtained hereThe conjugate fiber was prepared as a nanofiber assembly in the same manner as in example 9. The number average single fiber diameter of the nanofiber was 50nm (2X 10) ^-5 Dtex) to the original fineness and the single fiber fineness deviation is very small.

Example 17

Except that the melt viscosity was 200 pas (300 ℃ C., 121.6 seconds) ^-1 ) Polyphenylene Sulfide (PPS) having a melting point of 280 ℃ and a melt viscosity of 200 pas (300 ℃ C., 121.6 seconds) ^-1 ) Except that PMP and PS were replaced with N6, kneading, melt spinning, drawing and heat treatment were carried out in the same manner as in example 15. In this case, the mixing ratio of the polymer was 20 wt% of PPS and 80 wt% of N6, the PPS melt temperature was 320 ℃, the N6 melt temperature was 270 ℃, the spinning temperature was 320 ℃, the nozzle face temperature was 300 ℃, and the single hole discharge amount was 1.0 g/min. To obtain a polymer blend with 77 dtex, 36 filaments, a strength of 5.2cN/dtex, an elongation of 50%Gold fibers. The TEM observation of the cross section of the obtained polymer alloy fiber revealed that a polymer alloy fiber in which N6 was sea, PPS was of an island-in-sea structure having islands, the number average diameter of the island region of PPS was 65nm, and PPS nanofibers were uniformly dispersed was obtained.

Using the polymer alloy fibers obtained here, circular knitted fabrics were produced in the same manner as in example 1, and then N6 was dissolved out with formic acid to obtain circular knitted fabrics composed of PPS nanofiber aggregates. The number average single fiber diameter of the nanofiber was 68nm (5X 10) ^-5 Decitex) to a fineness that it would not have before, and the single fiber fineness deviation is very small.

Watch 10

Island polymers			Sea polymers			Mixing sequence
Island polymers			Sea polymers				Polymer and process for producing the same	Melt viscosity Degree of rotation (Pa·s)	Ratio of (wt％)	Polymer and method of making same	Melt viscosity Degree of rotation (Pa·s)	Ratio of (wt％)
Example 14 Example 15 Example 16 Example 17	PC PMP PP PPS	300 300 300 200	20 20 20 20	Water soluble in hot water Neutral polymer PS Hot water soluble Neutral polymer N6	350 300 600 200		Polymer and process for producing the same	Melt viscosity Degree of rotation (Pa·s)	Ratio of (wt％)	Polymer and method of making same	Melt viscosity Degree of rotation (Pa·s)	Ratio of (wt％)	80 80 80 80	Spinning assembly Inner part Spinning assembly Inner part Spinning assembly Inner part Spinning assembly Inner part

TABLE 11

Island region Number average diameter (nm)	Island regional deviation		Strength of (cN/dtex)	U％ (％)
	Island regional deviation				Area ratio (％)	Range Diameter range: area ratio
	Example 14 Example 15 Example 16 Example 17	85 70 48 65			Area ratio (％)	Range Diameter range: area ratio	73 95 100 98	75～104nm：70％ 65～94nm：73％ 45～74nm：75％ 55～84nm：70％	2.2 3.0 2.5 5.2	5.1 2.0 2.0 2.0

Area ratio: the island region has an area ratio of 1 to 100nm in diameter

The range is as follows: at an area ratio between 30nm of diameter difference.

TABLE 12

Number average of nanofibers		Deviation of nanofiber		Strength of (cN/dtex)
Number average of nanofibers		Deviation of nanofiber			Diameter of (nm)	Fineness of fiber (dtex)	Fineness ratio (％)	Range Diameter range: fineness ratio
Example 14 Example 15 Example 16 Example 17	88 73 50 68	8×10 ^-5 5×10 ^-5 2×10 ^-5 5×10 ^-5	70 94 100 92		Diameter of (nm)	Fineness of fiber (dtex)	Fineness ratio (％)	Range Diameter range: fineness ratio	85～114nm：70％ 65～94nm：72％ 45～74nm：72％ 65～94nm：68％	1.5 1.7 1.5 3.0

Example 18

Flat fabrics were made using the polymer alloy fibers made in examples 1-6. The resulting plain fabric was refined in 100 ℃ hot water (bath ratio 1: 100) containing a surfactant (Sanyo chemical "グランァップ" (registered trademark)) and sodium carbonate at a concentration of 2 g/liter, respectively. The refining time was 40 minutes. Intermediate adjustments were made at 140 ℃. Then, the resultant was subjected to alkali treatment with a 10% aqueous solution of sodium hydroxide (bath ratio 1: 100 at 90 ℃ C.) for 90 minutes to remove 99% or more of the copolymerized PET as the sea component. The final adjustment was then carried out at 140 ℃. This resulted in a fabric comprising a nanofiber aggregate.

The obtained fabric was dyed by a usual method, and any of the fabrics was dyed in a beautiful color without dyeing unevenness. The fabric composed of the nanofiber aggregate obtained here is a fabric of excellent quality and style such as "rough feel" like silk fabric or "dry feel" like rayon. Further, Δ MR =6% and excellent moisture absorption are preferable as comfortable clothing. The results of polishing the fabric showed that the fabric had a quality texture that was superior in super-texture and delicate feeling like body moisture, which could not be obtained with the original ultrafine fibers.

Comparative example 6

A flat woven fabric was produced in the same manner as in example 18 using the N6 hybrid fibers produced in comparative examples 2 to 4. However, since the spinning is unstable and many knots and fuzz are generated in the longitudinal direction of the yarn, only a fabric having a poor surface quality and being much fuzzed is obtained, and the refining is performed on the fabric, followed by intermediate conditioning. Then, the filaments of comparative example 2 were subjected to alkali treatment in the same manner as in example 18, and then subjected to final conditioning. Dyeing is also carried out by the usual methods. On the other hand, the filaments of comparative examples 3 and 4 were immersed in toluene at 85 ℃ for 60 minutes to remove 99% or more of PE. Then, it is finally adjusted. Dyeing is carried out by a conventional method. This fabric is a poor quality fabric with a large amount of dyed stains and fuzz. The fiber had a mass tone in the category of original very fine fibers, had no "rough feeling" or "dry feeling", and had a moisture absorption comparable to that of normal N6 fibers (Δ MR = 2%).

Example 19

Fabrication of high Density Using Polymer alloy fibers made in example 4Fabric (5 back satins). Further, in the same manner as in example 18, a basis weight of 150g/m was obtained from the nanofiber aggregate ² The fabric of (1). Then, as a result of analysis of the variation in the single fiber fineness of the nanofibers in the same manner as in example 1, the single fiber diameter of the nanofibers was 86nm (6X 10) ^-5 Decitex) finer than the original. The single fiber fineness was 1X 10 ^-7 ～1×10 ^-4 The fineness ratio of dtex is 78%, and particularly the single fiber fineness ratio with a single fiber diameter of 75 to 104nm is 64%, and the variation of single fiber fineness is small. When its fabric is immersed in water, it shows specific adhesion. Further, the fabric was subjected to polishing treatment to obtain a wipe. This wiper is superior in wiping treatment performance to the conventional ultra-fine wire wiper, and is preferably used as a wiper. The wiper was thrown into a washing net by a household washing machine to wash and dewater, and showed good dimensional stability without change in shape.

Example 20

The polymer alloy fibers prepared in example 1 were combined to obtain a4 ten-kilo-dtex tow, which was mechanically crimped to obtain a crimped yarn having a crimp number of 8/25 mm. The fiber was cut into a length of 51mm, and after defibration by a carding machine, a crossweb machine (クロスラップゥェ - バ -one) was used to produce a web. Then, the web was needled to 3000 roots/cm ² To make the basis weight of 750g/m ² The fiber complex nonwoven fabric of (1). Then, a PP nonwoven fabric was bonded to the nonwoven fabric as a support. After polyvinyl alcohol was added to the laminated nonwoven fabric, alkali treatment was performed with a 3% aqueous sodium hydroxide solution (60 ℃ C., bath ratio 1: 100) for 2 hours to remove 99% or more of copolymerized PET. The nonwoven fabric laminate was immersed in a liquid composed of 13 wt% of a polyurethane composition (hereinafter abbreviated as "PU") mainly composed of polyether polyurethane and 87 wt% of N, N' -dimethylformamide (hereinafter abbreviated as "DMF"), and the PU was coagulated in an aqueous solution of 40 wt% of DMF and then washed with water to obtain a fibrous structure having a thickness of about 1mm composed of an N6 nanofiber aggregate and PU. Further, a nanofiber aggregate is drawn from the fiber structure, and nanofibers are alignedThe single fiber fineness deviation of (2) was analyzed in the same manner as in example 1, and as a result, the number average single fiber diameter of the nanofibers reached 60nm(3×10 ^-5 Decitex) to a fineness not originally present. The single fiber fineness was 1X 10 ^-7 ～1 ×10 ^-4 The single fiber fineness ratio in the dtex range is 97%, particularly the single fiber fineness ratio with a single fiber diameter of 55 to 84nm is 70%, and the deviation of the single fiber fineness is particularly small. Then, a PP nonwoven fabric was cut out from the laminated nonwoven fabric to obtain an N6 nanofiber nonwoven fabric. And (3) polishing one side of the N6 nanofiber non-woven fabric by using sand paper to enable the thickness to reach 0.8mm, then processing the other side by using a diamond sanding machine to form a nanofiber aggregate standing hair side, and then dyeing and processing the nanofiber aggregate standing hair side to obtain the artificial leather with the simulated deerskin leather. The obtained product has excellent appearance, no dyeing spots and no problem on mechanical properties. In addition, compared with the original ultra-fine artificial leather, the artificial leather has softer and more delicate hand feeling. In addition, because of excellent hygroscopicity, the artificial leather has delicate and excellent quality style similar to human skin which the original artificial leather does not have.

Comparative example 7

The N6/PE mixed fiber obtained in comparative example 3 was mechanically crimped, cut into a fiber length of 51mm, defibrated by a carding machine, and then formed into a web by a cross web machine. Then, the web was needled to obtain a basis weight of 500g/m ² The fiber complex nonwoven fabric of (1). Then, the fiber-entangled nonwoven fabric was immersed in a liquid composed mainly of polyether polyurethane, which was composed of 13 wt% of a polyurethane composition (PU) and 87 wt% of N, N' -Dimethylformamide (DMF), and the PU was solidified in an aqueous solution of 40 wt% of DMF, followed by washing with water, to obtain a fiber structure containing N6/PE mixed fiber and PU. Further, the fiber structure was polished to obtain a fiber structure of about 1mn in thickness comprising N6 ultrafine filaments and PU, one surface of the fiber structure was polished with sandpaper to a thickness of 0.8mm, and the other surface was polished with a diamond grinder to form a nanofiber aggregateAnd (5) standing the rough surface, dyeing and processing to obtain the artificial leather with the suede leather. The quality style obtained does not exceed the quality style of the original artificial leather adopting the ultra-fine fibers.

Example 21

The polymer alloy fiber produced in example 1 was subjected to the same procedure as in example 20 to obtain a fiber structure composed of an N6 nanofiber aggregate having a PU content of 40 wt% and PU. Further, as a result of extracting a nanofiber aggregate from the fiber structure and analyzing the variation in the single fiber fineness of nanofibers in the same manner as in example 1, the number average single fiber diameter of nanofibers reached 60nm (3 × 10) ^-5 Dtex) to a fineness that has not been achieved before. The single fiber fineness was 1X 10 ^-7 ～1×10 ^-4 Decitex rangeThe single fiber fineness ratio of the periphery is 97%, especially the single fiber fineness ratio of the single fiber diameter between 55nm and 84nm is 70%, and the deviation of the single fiber fineness is particularly small. The fiber structure was cut into two parts and then the surfaces thereof were polished with JIS #240, #350, #500 sandpaper. It was sandwiched between upper and lower 2 fluorine-processed heating rolls spaced 1mm apart at a surface temperature of 150 ℃ and then heated at a rate of 0.7kg/cm ² After pressing, the resultant was quenched with a cooling roll having a surface temperature of 15 ℃ to obtain a polishing cloth having a smooth surface. The polishing cloth was evaluated by the following methods, and the results are shown in Table 13, and the smoothness of the object to be polished was improved and the number of scratches which had been a drawback was small as compared with the cloth using the conventional ultrafine fibers, thereby showing excellent abrasion resistance.

< evaluation of polishing: deformation of hard disk (テキスチャリング) >

The object to be ground: substrate finished with over-polishing after Ni-P plating on commercially available aluminum plate (average surface roughness =0.28 nm)

Grinding conditions are as follows: the substrate was mounted on a test apparatus and polished under the following conditions.

Grinding the granules: free abrasive grain slurry of diamond having average particle size of 0.1 μm

Dropping speed: 4.5 ml/min

The number of rotations: 1000rpm

The belt speed is as follows: 6 cm/min

Grinding conditions are as follows: amplitude of 1 mm-300 times/min of transverse vibration

Evaluation of the number of sheets: the base plate 30 pieces/level

< average surface roughness Ra of object to be polished >

The surface roughness of the substrate 30 piece/level was measured by using an inter-filament force microscope (AFM) manufactured by Veeco with a sound-proof device installed in a clean room at 20 ℃ and a relative humidity of 50%, and the average surface roughness Ra was obtained. The measurement range was measured at the center 2 of the radius of each substrate, which was symmetrically selected with respect to the center of the disk, and the width of each point was 5. Mu. M.times.5. Mu.m.

< number of notches >

The number of cuts (X) on the surface of each sample was measured using an interference microscope manufactured by ZYGO. The counted score size is 0.1 μm × 100 μm or a number of the same or more. This was measured as a block/level of the substrate 30, and the number y of the damaged points was defined as the number of notches β.

Y = from X ≦ 4 time

Y =5 when X ≧ 5

β＝∑y _i (i＝1～30)

Here, Σ y _i Is the total number of scores for 30 pieces of sample.

Comparative example 8

A fiber structure composed of N6 ultrafine fibers and PU was obtained in the same manner as in comparative example 7. Using this, an abrasive cloth was produced in the same manner as in example 21. When this polishing cloth was evaluated, ra =1.60nm and β =32, the smoothness of the polished object was low, the number of scratches which were defects was large, and the polishing property was poor, as compared with the case of using the nanofiber aggregate.

Watch 13

	Raw silk	Ra(nm)	Beta (pieces/30)
	Raw silk	Ra(nm)	Beta (pieces/30)	Example 21 Comparative example 8	Example 1 Comparative example 7	0.09 1.60	2 32

Example 22

Using the polymer alloy fiber produced in example 1, the same procedure as in example 20 was conducted to obtain a basis weight of 350g/m ² The fiber of (2) is complexed with the nonwoven fabric. The nonwoven fabric was subjected to alkali treatment with a 10% aqueous solution of sodium hydroxide (90 ℃ C., bath ratio 1: 100) for 2 hours to remove 99% or more of copolymerized PET, thereby obtaining an N6 nm nonwoven fabric. Further, as a result of extracting a nanofiber aggregate from the nonwoven fabric and analyzing the variation in the single fiber fineness of the nanofibers in the same manner as in example 1, the number average single fiber diameter of the nanofibers reached 60nm (3 × 10) ^-5 Decitex) to a fineness not originally present. The single fiber fineness was 1X 10 ^-7 ～1 ×10 ^-4 The single fiber fineness ratio in decitex range is 97%, especially the single fiber fineness ratio with single fiber diameter between 55-84 nm is 70%, and the deviation of single fiber fineness is especiallyIs small. Then, the obtained N6 nanometer nonwoven fabric was cut into a circle having a diameter of 4.7cm, 5 pieces of the nonwoven fabric were stacked and set in a column of a circular filter, bovine blood containing leukocytes (5700/microliter) was introduced into the filter at a flow rate of 2 ml/minute, and the time required for the pressure loss to reach 100mmHg was 100 minutes, whereby the removal rate of granulocytes was 99% or more and the removal rate of robusta was 60%, and granulocytes of inflammatory leukocytes were selected. This is believed to be due to the effect of the gaps between the nanofibers.

Example 23

0.5g of the nanofiber nonwoven fabric prepared in example 22 was sterilized by autoclave, and then bovine serum containing 15ml of endotoxin was passed through the autoclave to evaluate the adsorption capacity (37 ℃ C., 2 hours). Endotoxin concentration LPS was reduced from 10.0ng/ml to 1.5ng/ml, showing excellent adsorption capacity. This is because nylon nanofibers have a larger active surface than ordinary nylon fibers and have more amino terminals than ordinary nylon fibers.

Example 24

A spunbonded nonwoven fabric was produced by combining the same polymers as in example 13 and using the apparatus shown in FIG. 18. At this time, the melt temperature in the twin-screw extruder 23 was 225 ℃, the spinning temperature was 230 ℃ and the nozzle face temperature was 217 ℃. Further, the same spots as in example 1 were used for the nozzles, and the amount of the single-hole discharge was 0.8 g/min, and the distance from the lower surface of the nozzle to the start of cooling was 12cm.

The obtained polymer alloy nonwoven fabric was treated with hot water at 60 ℃ for 2 hours to dissolve and remove 99% or more of the hot-water-soluble polymer, thereby obtaining a nonwoven fabric composed of PLA nanofibers. The number average of single fiber diameter of the nano fiber reaches 50nm (2 x 10) ^-5 Dtex). The single fiber fineness was 1X 10 ^-7 ～1×10 ^-4 The single fiber fineness ratio in the dtex range is 98% or more, and the single fiber fineness ratio with a single fiber diameter of 45-74 nm is 70%.

Example 25

The circular knitted fabric comprising the nanofiber aggregates prepared in examples 1 to 6 was immersed in a 15 wt% aqueous solution of hexamethylene diisocyanate and hexamethylene polycarbonate (molecular weight 3000 to 4000) having a molecular weight of 1000 for 30 minutes. Then, the circular braid was taken out, and the polyurethane prepolymer was crosslinked at 120 ℃ for 20 minutes. By this operation, the polyurethane prepolymer impregnated into the space between the nanofibers is insolubilized by crosslinking, and a composite composed of the crosslinked polyurethane and the N6 nanofibers is produced. The resulting circular braid-shaped composite has a large elongation and at the same time has a surface hand with satisfactory adhesiveness.

Example 26

The circular knitted fabric comprising the nanofiber aggregates prepared in examples 1 to 6 was immersed in ion-exchanged water, and 1,2-bis (trimethoxysilyl) ethane was added thereto, and the mixture was stirred for 3 hours, left to stand at room temperature for 14 hours, then stirred for 13 hours, left to stand at room temperature for 14 hours, and then stirred for 7 hours, thereby polymerizing silica. Then, the circular knitted fabric was washed with ion-exchanged water and then air-dried. By this operation, a fabric-shaped N6/silica composite was obtained using the N6 nanofibers as a mold. This is an excellent material having sufficient rigidity and flexibility. In addition, the flame retardant is also a mixed material with excellent flame retardancy.

Example 27

The N6/silica composite obtained in example 26 was calcined at 600 ℃ to remove N6 used for the casting, thereby obtaining a silica sheet having many fine pores with a diameter of several tens of nm. It shows excellent adsorption and deodorizing performance.

Example 28

The knitted fabrics composed of the polyester nanofiber aggregates produced in examples 9 to 12 were made to absorb "SR1000" (10% aqueous dispersion) produced by kokusu fat (ltd.) as a moisture absorbent. The processing conditions in this case were 20% owf of the solid content of the moisture absorbent, 1: 20 of the bath ratio, 130 ℃ of the treatment temperature and 1 hour of the treatment time. The exhaustion rate of the moisture absorbent by the normal polyester fiber is almost 0%, but the exhaustion rate of the moisture absorbent by the polyester nanofiber is 10% or more, and Δ MR =4% or more, and a polyester knitted fabric having excellent moisture absorption equivalent to or more than cotton can be obtained.

Example 29: mixture (nanofiber/silicone)

Methyltrimethoxysilane oligomer (n =3 to 4) was dissolved in a mixed solution of isopropanol/ethylene glycol =1/1, and dibutyl tin diacetate as a polymerization catalyst was added in an amount of 4 wt% relative to the silane oligomer to prepare a silicone polymer coating solution. The fabric comprising the N6 nanofiber aggregate produced in example 19 was immersed in the coating solution at 30 ℃ for 20 minutes, and the coating solution was sufficiently immersed in the solution. Then, the fabric was taken out from the coating solution, and silicone polymerization was carried out while drying at 60 ℃,2 minutes, 80 ℃,2 minutes, 100 ℃,2 minutes, to obtain a fabric in which N6 nanofibers were coated with a silicone polymer. It is a fabric having excellent hydrophobicity and flame retardancy.

Example 30

The moisture content and water retention of the knitted fabric comprising the N6 nanofiber aggregates produced in examples 1 to 4 were measured. The knitted fabric exhibits a water content of 160% or more by weight and a water retention of 80% or more by weight, and is excellent in water absorption and water retention. Here, the water content and water retention are calculated by immersing the sample in a water bath for 60 minutes, taking it out, measuring the weight of the fabric (Ag) after removing the water attached to the surface, then dewatering it with a centrifugal dehydrator (3000 rpm,7 minutes), measuring the weight of the fabric (Bg), and measuring the weight of the fabric (Cg) after drying at 105 ℃ for 2 hours, according to the following formula:

water content (%) = (A-C)/C × 100 (%)

Water retention (%) = (B-C)/C X100 (%)

The knitted fabric comprising the N6 nanofiber aggregate exhibits a specific adhesiveness particularly in a state of containing 15% or more of water.

Example 31

The N6 nanofiber nonwoven fabric produced in example 22 was used to produce a base fabric for a patch material, and a chemical was applied to the base fabric, whereby the base fabric was excellent in the absorbability of the chemical, showed excellent adhesiveness, and was used as an excellent paste.

Example 32

A bag was produced from a knitted fabric comprising the N6 nanofiber aggregate produced in example 1, and a cold insulating agent packed in the bag was placed in the bag to produce an apparatus for hot and cold compression (an apparatus for hot and cold まレ). The hot and cold compress tool absorbs water condensed in the bag and exhibits excellent adhesiveness, so that the hot and cold compress tool is difficult to separate from an affected part and has excellent operability.

Example 33

The removal ability of organic contaminants of the circular knitted fabric comprising the N6 nanofiber aggregate prepared in example 1 was evaluated by the following method. 1g of sample piece was put in a 0.005m container ³ In a four-port (5 liter) tank, air containing organic pollutants was introduced to a desired concentration. The contaminated air was sampled at any time, and the concentration of organic contaminants in the four-port tank was monitored by a gas chromatograph.

The evaluation results of the removal of ammonia, formaldehyde, toluene and hydrogen sulfide as organic contaminants showed excellent removal ability (fig. 19 to 22).

Comparative example 9

The removal ability of organic contaminants was evaluated in the same manner as in example 33 using a commercially available N6 plain cloth, and almost no removal ability was exhibited.

Example 34

Leather shoes were produced by using the circular knitted fabric comprising the N6 nanofiber aggregate produced in example 1, and were immersed in "new ポリカィン (registered trademark) solution" produced by the university of penc pharmaceutical company and then dried. Thus, leather shoes can be obtained in which the beriberi agent is dissolved out by the juice. The leather shoes are worn by 10 people suffering from beriberi, and the shoes are replaced with new ones every day. In 1 month, 7 subjects with improvement in symptoms were observed. This is due to the slow release of the beriberi.

Therefore, the nanofibers of the present invention are suitable as pharmaceutical products because they have the ability to slowly release the pharmaceutically effective components.

Example 35

The circular knitted fabric produced in example 4 was immersed in a 10 wt% aqueous solution of silicone PP (produced by specially modified silicone/rosin oil & fat, ltd.), and a treatment solution was applied to the circular knitted fabric base so that the immersion rate of the aqueous solution became 150%. After the treatment liquid was applied, it was dried in an oven at 110 ℃ for 3 minutes in a relaxed state. After drying, the fabric is kneaded to have a delicate hand feeling different from that of polishing and a smooth feeling similar to human skin. In addition, the feeling of cold touch is also felt. In addition, the circular knitted fabric base material was thrown into a washing net by a household washing machine to be washed and dehydrated, and showed good dimensional stability without change in form.

The product treated with the silicone has a basis weight of 150g/cm ² The T-shirt made of the round knitted fabric base material consisting of the N6 nano fibers has very comfortable hand feeling like human skin and also has the anti-pilling effect. Further, the circular knitted fabric base material was thrown into a washing net by a household washing machine to be washed and dehydrated, and showed good dimensional stability without changing its form.

Example 36

The polymer alloy fiber produced in example 4 was subjected to false twist processing using a friction disc false twist processing device. At this time, the heat treatment temperature was 180 ℃ and the stretch ratio was 1.01 times. Using the false twist processed yarn obtained here, the basis weight of 100g/m consisting of the nanofiber aggregate was obtained by alkali treatment in the same manner as in example 1 ² The circular braid base material of (1). The single fiber fineness variation of these nanofibers was analyzed in the same manner as in example 1, and the number average single fiber diameter of the nanofibers was 84nm (6X 10) ^-5 Decitex) is the fineness that has not been achieved before. The single fiber fineness was 1X 10 ^-7 ～1×10 ^-4 The single fiber fineness ratio in the range of 78%, particularly the single fiber fineness ratio with a single fiber diameter in the range of 75 to 104nm, was 64%, and the variation in single fiber fineness was small. In addition, the N6 nmThe strength of the false twist textured yarn of the fiber is 2.0cN/dtex, and the elongation is 45%.

The circular knitted fabric base material was subjected to silicone treatment in the same manner as in example 35, and showed a delicate hand and a moist, delicate texture like human skin. It also has cold feeling. The circular knitwear was put into a washing net by a household washing machine to be washed and dehydrated, and showed good dimensional stability without change in shape.

Example 37

The silicone-treated basis weight prepared in example 36 was used, 100g/m ² The circular knitwear made of the N6 nano fibers is used for manufacturing female shorts, has very comfortable hand feeling like human skin, and also has the effect of preventing pilling. The circular knitwear was put into a washing net by a household washing machine to be washed and dehydrated, and showed good dimensional stability without change in shape.

Example 38

The N6/copolymerized PET alloy false-twisted yarn produced in example 36 was used as a sheath yarn, and a polyurethane elastic yarn "ラィクラ" (registered trademark) produced by ォペロンテックス was used as a core yarn. After producing a knit fabric for body clothing from this core spun yarn, the knit fabric for body clothing comprising nanofibers was produced by alkali treatment in the same manner as in example 36. The basis weight of the knitwear for tights is 100g/m ² The weight ratio of the N6 nanofibers and the polyurethane filaments was 90% and 10%, respectively. The resulting fabric was immersed in a 10 wt% aqueous solution of silicone (シルコ - ト) PP (manufactured by speciality modified silicone/Sonben grease Co., ltd.) to give a treatment liquid to the knitted fabric so that the impregnation rate of the aqueous solution became 150%. After the treatment liquid was applied, the treatment liquid was dried in an oven at 110 ℃ for 3 minutes in a relaxed state. Drying and rubbing. Then, the knitwear for body suit is sewn to produce a body suit. The tights have a delicate texture and a lubricating texture similar to that of human skin. The wearing is very comfortable.

Example 39

The speed (spinning speed) of the drawing roll 9 of the 1 st drawing roll was set to 3500 m/min, and melt spinning was carried out in the same manner as in example 4 to obtain a 400 dtex 96-filament N6/copolymerized PET polymer alloy fiber having a strength of 2.5cN/dtex, an elongation of 35%, and a U% =1.9%. Then, the polymer alloy fiber was subjected to draw false twisting to obtain a false-twisted yarn of 333 dtex and 96 filaments. In this case, the heat treatment temperature was 180 ℃ and the draw ratio was 1.2 times. The obtained false twist textured yarn had a tenacity of 3.0cN/dtex and an elongation of 32%.

The false-twisted yarn was subjected to a weak twist of 300 rpm, and S-twist/Z-twist double yarns were used as warp and weft, to produce a 2/2 rib fabric. Then, the rib fabric obtained was subjected to alkali treatment in the same manner as in example 1 to obtain 150g/m of conjugate fiber composed of N6 nanofibers ² The curtain is made of natural color cloth. Further, as a result of analyzing the variation in the single fiber fineness of the nanofibers in the same manner as in example 1, the number average single fiber diameter of the nanofibers reached 86nm (6X 10) ^-5 Decitex) to a fineness not originally present. Further, the single fiber degree was 1X 10 ^-7 ～1×10 ^-4 The single fiber fineness ratio in the dtex range is 78%, and particularly the single fiber fineness ratio with a single fiber diameter of 75 to 104nm is 64%, and the deviation of the single fiber fineness is particularly small. The N6 nanofiber false-twist textured yarn had a strength of 2.0cN/dtex and an elongation of 40%.

The same silicone treatment as in example 35 was performed on this natural color cloth for a curtain, and as a result, a fine texture and a smooth texture similar to human skin were exhibited. In addition, the touch cold feeling is also provided. The moisture absorption rate (. DELTA.MR) was 6%, and the moisture absorption rate (. DELTA.MR) was sufficient, and the concentration was decreased from 100ppm to 1ppm for 10 minutes as a result of the acetic acid deodorization test, thereby showing excellent deodorization. In addition, the curtain made of the natural color cloth can form a bright indoor environment as a result of hanging 6 straw mat rooms, and can inhibit condensation. The window curtain is thrown into a washing net for washing and dewatering by the household washing machine, the shape is not changed, and good dimensional stability is displayed.

Example 40

The N6/copolymerized PET polymer alloy used in example 4 and the melt viscosity 500 pas (262 ℃ C., shear rate 121.6 seconds) used in example 4 were mixed ^-1 ) And N6 having a melting point of 220 ℃ were melted, and a core-sheath composite yarn was produced in the same manner as in example 4 using a nozzle having a Y-shaped discharge hole. In this case, the core component was an N6/copolymerized PET polymer alloy, the shell component was N6, and the core component compounding ratio was 50% by weight. The spun yarn was drawn at 800 m/min, then drawn at 2 stages under conditions of a 1 st draw ratio of 1.3 and a total draw ratio of 3.5, crimped with a nozzle, and then wound to obtain a bulked processed yarn of 90 filaments at 500 dtex. The bulked processing yarn had a strength of 5.2cN/dtex and an elongation of 25%.

The obtained bulked processed yarns were combined at 2 times, subjected to primary twisting (200T/m), and 2 of them were twisted by secondary twisting (200T/m), subjected to twist-stop treatment at dry heat of 170 ℃ and then made into fancy yarn as cut pile carpet by a known method. At this time, the normal horizontal cutting is adopted, and the stitch is adjusted to reach 1/1 row spacing and the eye payment is 1500g/m ² And making into the fancy wool yarn. Then, packaging is performed. When producing the fancy wool yarn, a base fabric woven from a blended yarn of acrylic fibers and polyester fibers is used as the base fabric. In addition, only the cut pile portion was subjected to alkali treatment, and the N6 nanofibers exhibited a structure in which N6 was wrapped in the cut pile portion.The number average single fiber diameter of the obtained N6 nanofibers was 86nm (6X 10) ^-5 Decitex). The single fiber fineness was 1X 10 ^-7 ～1×10 ^-4 The single fiber fineness ratio in the dtex range is 78%, and particularly the single fiber fineness ratio with a single fiber diameter of 75 to 104nm is 64%, and the variation in single fiber fineness is particularly small. Therefore, the basis weight of the cut pile portion becomes 1200g/m ² The weight fraction of the N6 nanofibers was 33 wt% of the cut pile portion, and 15 wt% of the entire carpet. In this carpet, the cut pile portion retains the N6 nanofibers by the shell component N6, and therefore the problem of fuzziness (fuzziness れ) does not occur.In addition, the N6 nanofiber content of the entire carpet was 15 wt%, so that sufficient moisture-adjusting and deodorizing properties were exhibited, and a fresh indoor environment was achieved. Further, condensation can be suppressed.

EXAMPLE 41

The 4N 6/copolymerized PET alloy false twist textured yarns obtained in example 36 were combined and used as warp and weft yarns to produce a 2/2 rib fabric. Then, alkali treatment was carried out in the same manner as in example 36 to obtain a textured yarn composed of N6 nanofibers false twisted yarn of 200g/m ² The sheet skin for interior decoration of (1). Further, as a result of analysis of the single fiber fineness variation of the nanofibers in the same manner as in example 1, the number average single fiber diameter of the nanofibers reached 86nm (6X 10) ^-5 Decitex) to a fineness not originally present. The single fiber fineness was 1X 10 ^-7 ～1×10 ^-4 The single fiber fineness ratio in the dtex range is 78%, and particularly the single fiber fineness ratio with a single fiber diameter of 75 to 104nm is 64%, and the deviation of the single fiber fineness is particularly small. When used as the surface of a chair, the product is soft and comfortable, and has sufficient humidity regulation and deodorization performance, thereby forming a bright indoor environment.

Example 42

The N6/copolymerized PET polymer alloy used in example 4 and the melt viscosity 500 pas (262 ℃ C., shear rate 121.6 seconds) used in example 4 were mixed ^-1 ) And N6 having a melting point of 220 ℃ was melted, and a core-sheath composite yarn was produced in the same manner as in example 4 using a circular Kong Penju. In this case, the core component was an N6/copolymerized PET polymer alloy, the shell component was N6, and the core component compounding ratio was 30% by weight. The spun yarn was once taken up at 1600 m/min, and then drawn at a draw ratio of 2.7 times at a temperature of 90 ℃ on the 1

st heating roller

17 and 130 ℃ on the 2 nd heating roller 18. The obtained polymer alloy fiber has the advantages of 220 dtex, 144 filaments, 4.8cN/dtex strength, 35% elongation and U% =1.9%. Then, a plain weave fabric was produced by using the warp and weft with a weak twist of 300 revolutions/m. Then, the alkali treatment was carried out in the same manner as in example 4 to obtain a covering material composed of N6 nanofibersBasis weight 220g/m composed of N6-coated fibers ² The fabric of (1).The number average single fiber diameter of the obtained nanofibers was 86nm (6X 10) ^-4 Decitex). Further, the single fiber fineness was 1X 10 ^-7 ～1×10 ^-4 The single fiber fineness ratio in the dtex range is 78%, particularly the single fiber fineness ratio with a single fiber diameter of 75 to 104nm is 64%, and the deviation of the single fiber fineness is particularly small. Further, this was subjected to silicone treatment in the same manner as in example 36, and as a result, a delicate texture and a smooth quality texture similar to human skin were exhibited. The quilt cover and the bed sheet made of the material have excellent quality and style and very comfortable moisture absorption. In addition, due to its excellent deodorizing properties, odor can be suppressed even when incontinence occurs. In addition, these bedding articles were washed and dehydrated in a washing net by a household washing machine, and showed good dimensional stability without change in form.

Example 43

The speed of the 1 st take-up roll 9 was 3500 m/min, and a core-sheath composite yarn was produced in the same manner as in example 40 to obtain a N6/copolymerized PET polymer alloy fiber of 264 dtex and 144 filaments. The strength of the polymer alloy fiber is 3.5cN/dtex, the elongation is 110%, and U% =1.9%. Then, the yarn was subjected to draw false twisting to obtain a false-twisted yarn of 220 dtex and 144 filaments. At this time, the film was heat-treated at 180 ℃ to obtain a stretch ratio of 1.2. The false twist textured yarn obtained had a tenacity of 4.1cN/dtex and an elongation of 32%.

The false twist yarn was subjected to weak twisting at 300 rpm, and used as warp and weft to produce a plain woven fabric. Then, the alkali treatment was carried out in the same manner as in example 1 to obtain a basis weight of 100g/m comprising N6 nanofibers ² The N6 nanofibers of (2) are coated with the N6 shell component. Further, as a result of analyzing the single fiber fineness variation of the nanofibers thus obtained in the same manner as in example 1, the number average single fiber diameter of the nanofibers was 86nm (6X 10) ^-5 Dtex) to a fineness not originally present. The single fiber fineness was 1X 10 ^-7 ～1×10 ^-4 The single fiber fineness ratio in the dtex range is 78%, particularly 64% with a single fiber diameter of 75 to 104nm, and the variation in single fiber fineness is particularly small. The fabric is a structure in which N6 nanofibers in N6 hollow yarns are encapsulated, and presents a quality style similar to cotton candy in hand feeling and excellent elasticity. The false twist textured yarn strength of the N6-containing nano fiber is 2.9cN/dtex, and the elongation is 41%.

The fabric was subjected to silicone treatment in the same manner as in example 35, and as a result, the fabric showed a delicate texture and a smooth texture like human skin. In addition, the touch cold feeling is also provided. The moisture absorption rate (. DELTA.MR) was 6%, and the film showed sufficient moisture absorption. The female shirt made of the fabric is very comfortable and has the anti-pilling effect. In addition, these female shirts were washed and dehydrated in a washing net using a home washing machine without change in form, and the N6 fiber showed good dimensional stability by being encapsulated with N6 hollow yarn.

Example 44

The N6/copolymerized PET alloy false-twist textured yarn produced in example 39 was used as a base structure, and a tricot knit fabric having a raised pile portion made of 100 dtex or 36-filament polybutylene terephthalate (PBT) yarn was knitted with a 28-needle knitting machine at a knitting density of 64 courses. Then, the resultant was immersed in a 10% aqueous sodium hydroxide solution (90 ℃ C., bath ratio 1: 100) for 1 hour to hydrolyze and remove 99% or more of the copolymerized PET in the polymer alloy fibers, thereby obtaining an automobile interior fabric. As a result, the basis weight of the obtained fabric for automobile interior decoration was 130g/m ² The N6 nanofiber content was 40% by weight. The basis weight of the N6 nanofibers was 120g/m ² . The number-average single fiber diameter of the N6 nanofibers was 84nm (6X 10) ^-5 Decitex) to a fineness not originally present. The single fiber fineness was 1X 10 ^-7 ～1×10 ^-4 The single fiber fineness ratio in dtex range is up to 78%, especially the single fiber fineness ratio with single fiber diameter between 75-104 nm is 64%, the single fiber fineness isThe deviation is particularly small. Then, the fiber was immersed in a 30% aqueous solution of diethylenetriamine at 50 ℃ for 1 minute, thereby supporting diethylenetriamine on the N6 nanofibers. As a result of evaluation of the acetoacetal-removing ability, the concentration was decreased from 30ppm to 1ppm in 10 minutes, and the excellent acetoacetal-removing ability was exhibited.

Example 45

The N6/copolymerized PET polymer alloy used in example 4 and the melt viscosity 240 pas (262 ℃, shearing speed 121.6 seconds) were mixed ^-1 ) PBT having a melting point of 220 ℃ was melted, and sea-island composite spinning was carried out in the same manner as in example 4 using a nozzle having a hole number of 24, a discharge hole diameter of 1.0mm, and a discharge hole length of 1.0 mm. In this case, the sea component was an N6/copolymerized PET polymer alloy, the island component was PBT, the island component compounding ratio was 35 wt%, and the number of islands per hole was 36 islands. After the spun yarn was drawn at 900 m/min, the drawn yarn was drawn at a draw ratio of 3.0 times at a temperature of 80 ℃ at the 1

st heating roll

17 and 130 ℃ at the 2 nd heating roll 18, and then heat-treated. The obtained polymer alloy with 240 dtex, 24 filaments, strength of 3.0cN/dtex, elongation of 40 percent and U% =2.0 percent is sea, and PBT is island-in-sea composite filament of islands. Then, after the weak twist was performed at 300 rpm, it was used as warp and weft to produce a 2/2 rib fabric. Then, the fabric was immersed in a 10% aqueous solution of sodium hydroxide (90 ℃ C., bath ratio 1: 100) and hydrolyzed to remove 99% or more of copolymerized PET in the polymer alloy fibers. Thus, a weight ratio of N6 nanofibers to PBT of 48 wt%: 52 wt% of a mixed yarn of N6 nanofibers and PBT ultrafine fibers (0.08 dtex) having a basis weight of 200g/m ² The fabric of (1). In addition, the number average single fiber diameter of the N6 nano fiber reaches 84nm(6×10 ^-5 Decitex) to a fineness not originally present. The single fiber fineness was 1X 10 ^-7 ～1 ×10 ^-4 The single fiber fineness ratio in the dtex range is 78%, and particularly the single fiber fineness ratio with a single fiber diameter of 75 to 104nm is 64%, and the variation in single fiber fineness is particularly small.

The fabric is developed from N6 nanofibers by electrostatic repulsion due to the difference in chargeability between the N6 nanofibers and PBT, and can provide a super soft and super-hand feeling without polishing or silicone treatment, and has a delicate and excellent quality style like human skin. In addition, the PBT supports the fabric skeleton, so that the dimensional stability can be improved, and the excellent resilience feeling is achieved. The windproof sportswear is produced by using the fabric, but the excellent windproof property is exhibited by opening the N6 nanofibers, and the sportswear having a super soft quality style is produced, so that the sportswear has no "sand" sound even if the sportswear is violently exercised, and the sportswear has a very comfortable property due to the excellent hygroscopicity of the N6 nanofibers. In addition, the fabric was placed in a washing net by a household washing machine to be washed and dehydrated, and showed good dimensional stability without change in shape.

Example 46

The nanofiber aggregate prepared in example 1 was minced in water, and 0.1 wt% of a nonionic dispersant containing polyoxyethylene styrene sulfonated ether as a main component was added to obtain an N6 nanofiber aqueous dispersion. The concentration of N6 nanofibers in water was 1% by weight. The aqueous dispersion was cast on a carbon nanofiber-containing composite to be dried, and the surface of the carbon fiber composite was thinly coated with N6 nanofibers. Thereby increasing the hydrophilicity of the composite surface of the carbon fiber.

Example 47

The polymer alloy fiber obtained in example 1 was formed into a 10 dtex tow and then finely cut into a fiber length of 2mm. Then, the same alkali treatment as in example 1 was carried out to obtain a nanofiber aggregate. The aqueous alkali solution in which the nanofiber aggregate was dispersed was neutralized with dilute hydrochloric acid, and 0.1 wt% of a nonionic dispersant containing polyoxyethylene styrene sulfonated ether as a main component was added to the aqueous alkali solution, and then the resulting mixture was subjected to papermaking to obtain a nonwoven fabric. The nonwoven fabric obtained here is different from a nonwoven fabric produced by needling in which a nanofiber aggregate is aggregated to a diameter of 10 μm or more, and the dispersion of the nanofiber aggregate in diameter is 300nm or less. Further, the nanofiber aggregate is extracted from the nonwoven fabricThe number average single fiber diameter of the nanofibers reached 60nm (3X 10) as a result of analysis of the single fiber fineness variation of the nanofibers in the same manner as in example 1 ^-5 Decitex) to a fineness not originally present. The single fiber fineness was 1X 10 ^-7 ～1×10 ^-4 A unit of decitex rangeThe fiber fineness ratio is 99%, particularly the single fiber fineness ratio with a single fiber diameter of 55 to 84nm is 70%, and the deviation of the single fiber fineness is particularly small.

Example 48

Except that the polymer had a weight-average molecular weight of 12 ten thousand and a melt viscosity of 30 pas (240 ℃ C., 2432 seconds) ^-1 ) And instead of copolymerized PET, poly L lactic acid (optical purity 99.5% or more) having a melting point of 170 ℃ was melt-kneaded in the same manner as in example 1 except that the kneading temperature was 220 ℃ to obtain b ^* A polymer alloy sheet having a value =3. The weight average molecular weight of the polylactic acid is determined by the following method. Tetrahydrofuran (abbreviated as THF) was mixed with a chloroform solution of the sample to prepare a measurement solution. The solution was measured at 25 ℃ by Gel Permeation Chromatography (GPC) Waters2690 manufactured by Waters corporation, and the weight average molecular weight in terms of polystyrene was determined. N6 used in example 1 was heated at 240 ℃ for 2432 seconds ^-1 Has a melt viscosity of 57 pas. The poly-L-lactic acid was dissolved at 215 ℃ for 1216 seconds ^-1 The melt viscosity of (2) was 86 pas.

Melt spinning was carried out in the same manner as in example 1 except that the polymer alloy sheet was melt-spun at a temperature of 230 ℃ and a spinning temperature of 230 ℃ (nozzle surface temperature 215 ℃) and at a spinning speed of 3500 m/min. In this case, a usual spinning nozzle having a nozzle hole diameter of 0.3mm and a hole length of 0.55mm was used as the nozzle, but the edge scumming phenomenon was hardly observed, and the spinnability was greatly improved as compared with example 1, and the yarn breakage was 0 times during 1 ton spinning. The single-hole discharge amount at this time was 0.94 g/min. Therefore, a highly oriented undrawn yarn of 92 dtex and 36 filaments was obtained, which had a strength of 2.4cN/dtex, an elongation of 90%, a boiling water shrinkage of 43%, and U% =0.7%, and was extremely excellent as a highly oriented undrawn yarn. In particular, the edge scum is greatly reduced, and the silk streak is also greatly improved.

The highly oriented undrawn yarn was subjected to a drawing heat treatment in the same manner as in example 1, except that the drawing temperature was 90 ℃, the drawing magnification was 1.39 times, and the heat setting temperature was 130 ℃. The drawn yarn obtained had excellent properties of 67 dtex, 36 filaments, a strength of 3.6cN/dtex, an elongation of 40%, a boiling water shrinkage of 9%, and U% = 0.7%.

The cross section of the obtained polymer alloy fiber was observed by TEM to show that PLA (thin portion) was sea and N6 (thick portion) was island-in-sea structure of islands. The polymer alloy fiber with N6 island region having a number average diameter of 55nm and N6 uniformly dispersed in nanometer size was obtained.

The polymer alloy fiber obtained here was circularly woven in the same manner as in example 1, and then treated with an alkali to hydrolyze and remove 99% or more of PLA in the polymer alloy fiber. Thereby obtaining a nanofiber assembly. The single fiber fineness variation of the nanofibers was analyzed in the same manner as in example 1 to obtain nanofibersThe number average single fiber diameter of the fiber reaches 60nm (3 multiplied by 10) ^-5 Decitex) to a fineness not originally present. The deviation of the fineness of the single fiber is very small.

The circular knitted fabric comprising the nanofiber aggregate had a moisture absorption rate (. DELTA.MR) of 6% and a water absorption swelling rate in the filament length direction of 7%. The yarn composed of the N6 nanofiber aggregate had a strength of 2.0cN/dtex and an elongation of 45%. Further, the dry heat shrinkage at 140 ℃ was 3%. The circular knitted fabric was subjected to a buffing treatment, and as a result, exhibited a quality and texture having a superior hand and smoothness like human skin, which could not be obtained with the original ultrafine fibers.

TABLE 14

Island region Number average diameter (nm)	Island regional deviation		Strength of (cN/dtex)	U％ (％)
	Island regional deviation				Area ratio (％)	Range Diameter range: area ratio
	Example 48 Example 49 Example 50 Example 51 Example 52	55 50 45 50 40			Area ratio (％)	Range Diameter range: area ratio	100 100 100 100 100	45～74nm：73％ 45～74nm：70％ 35～64nm：70％ 45～74nm：70％ 35～64nm：70％	3.6 1.2 1.4 1.3 1.3	0.7 2.0 2.0 2.0 2.0

Area ratio: the island region has an area ratio of 1 to 100nm in diameter

The range is as follows: at an area ratio between 30nm of diameter difference.

Watch 15

Number average of nanofibers		Deviation of nanofiber		Nano-fiber Strength of (cN/dtex)
Number average of nanofibers		Deviation of nanofiber			Diameter of (nm)	Fineness of fiber (dtex)	Fineness ratio (％)	Range Diameter range: fineness ratio
Example 48 Example 49 Example 50 Example 51 Example 52	60 55 50 55 40	3×10 ^-6 3×10 ^-6 2×10 ^-6 3×10 ^-5 1×10 ^-5	99 100 100 100 100		Diameter of (nm)	Fineness of fiber (dtex)	Fineness ratio (％)	Range Diameter range: fineness ratio	55～84nm：70％ 45～74nm：70％ 45～74nm：70％ 45～74nm：70％ 35～64nm：70％	2.0 2.0 2.0 2.0 2.0

Fineness ratio: the fineness of single filament is 1X 10 ^-7 ～1×10 ^-4 Fineness ratio in decitex range

The range is as follows: at a titer ratio between 30nm in diameter difference.

Example 49

Melt kneading was carried out in the same manner as in example 1 except that 22% polystyrene (co-PS) copolymerized with 2-ethylhexyl acrylate was used as the copolymerized PET used in example 9, the content of the copolymerized PET was 20% by weight, and the kneading temperature was 235 ℃ to obtain b ^* Polymer alloy with value =2. At this time, the copoly-PC was at 262 ℃ for 121.6 seconds ^-1 Has a melt viscosity of 140 pas at 245 ℃ for 1216 seconds ^-1 The melt viscosity of (A) was 60 pas.

This polymer alloy was melt-spun in the same manner as in example 1, except that the melt temperature was 260 ℃, the spinning temperature was 260 ℃ (nozzle surface temperature 245 ℃), and the spinning speed was 1200 m/min. In this case, the same spinning nozzle as in example 1 was used as the nozzle, and the spinnability was good, and the yarn was broken 1 time during 1 ton of spinning. The single-hole discharge amount at this time was 1.15 g/min. Therefore, the obtained undrawn yarn was subjected to a drawing heat treatment at a drawing temperature of 100 ℃ and a drawing ratio of 2.49 times, using a hot plate having an effective length of 15cm as a heat curing device instead of a hot roll, and at a heat curing temperature of 115 ℃ in the same manner as in example 1. The drawn yarn obtained had properties of 166 dtex, 36 filaments, a strength of 1.2cN/dtex, an elongation of 27%, and U% =2.0%.

The cross section of the obtained polymer alloy fiber was observed by TEM to show that the copoly-PS was sea (thin portion) and the copoly-PET was sea-island structure of islands (thick portion). The obtained copolymerized PET island area polymer alloy fiber has the number average diameter of 50nm and the copolymerized PET is uniformly dispersed in nanometer size.

The polymer alloy fiber obtained here was circularly knitted in the same manner as in example 1, and then immersed in Tetrahydrofuran (THF) to elute 99% or more of the co-PS as a sea component. From which a nanofiber aggregate was obtained. The number average single fiber diameter of the nanofibers reached 55nm (3X 10) as a result of analysis of the single fiber fineness variation of the nanofibers in the same manner as in example 1 ^-5 Decitex) to a fineness that it did not. The deviation of the fineness of the single fiber is very small.

The polymer alloy fibers were combined to prepare a 10 ten-thousandth tow, and then cut into fibers having a length of 2mm. Then, this was treated with THF to elute the co-PS, thereby achieving nanofibrillation. The nanofiber-dispersed THF solution was subjected to solvent replacement with ethanol, followed by water, followed by beating and papermaking to obtain a nonwoven fabric. The nonwoven fabric obtained here is a fabric in which nanofibers are dispersed to the level of single fibers.

Example 50

Melt-kneading was carried out in the same manner as in example 1 except that the PBT used in example 11 and the copoly-PS used in example 49) were used, the PBT content was 20% by weight, and the kneading temperature was 240 ℃ or higher, to obtain b ^* Polymer alloy sheet with value =2.

The polymer alloy sheet was melt-spun in the same manner as in example 1, except that the melt temperature was 260 ℃, the spinning temperature was 260 ℃ (nozzle surface temperature 245 ℃), and the spinning speed was 1200 m/min. At this time, the same spinning nozzle as in example 1 was used as the nozzle, and the spinnability was good, and the yarn was broken 1 time during 1 ton of spinning. The single-hole discharge amount at this time was 1.0 g/min. The obtained undrawn yarn was subjected to a drawing heat treatment in the same manner as in example 49. The drawn yarn obtained was 161 dtex, 36 filaments, 1.4cN/dtex in strength, 33% in drawn length, and U% =2.0%.

The cross section of the obtained polymer alloy fiber was observed by TEM to show that the copoly-PS was sea (thin portion) and the copoly-PET was sea-island structure of islands (thick portion). The number average diameter of the copolymerized PET island region is 45nm, and the copolymerized PET is evenly dispersed in nanometer size.

The polymer alloy fiber obtained here was circularly knitted in the same manner as in example 1, and then impregnated with trichloroethylene, and 99% or more of the copolymerized-PS as a sea component was eluted. The nanofiber assembly was obtained therefrom. The number average single fiber diameter of the nanofibers reached 50nm (2X 10) as a result of analysis of the single fiber fineness variation of the nanofibers in the same manner as in example 1 ^-5 Decitex) to a fineness not originally present. The deviation of the fineness of the single fiber is very small.

Example 51

Except that PTT used in example 12 and copolymerized PS ("ェスチレン (registered trademark)", KS-18, methyl methacrylate having a melt viscosity of 110 pas, 262 ℃ and 121.6 seconds manufactured by Nippon iron chemical Co., ltd were used ^-1 ) Melt-kneading was carried out in the same manner as in example 1 except that the PTT content was 20% by weight and the kneading temperature was 240 ℃ to obtain b ^* Polymer alloy sheet with value =2. The copolymerized PS was carried out at 245 ℃ for 1216 seconds ^-1 Has a melt viscosity of 76 pas.

Melt spinning was carried out in the same manner as in example 1 except that the melt temperature was 260 ℃, the spinning temperature was 260 ℃ (nozzle surface temperature 245 ℃), and the spinning speed was 1200 m/min. In this case, as the nozzle, a spinning nozzle as shown in FIG. 13 similar to that of example 1, i.e., a metering portion 12 having a diameter of 0.23mm at the upper portion of the nozzle hole,a spinning nozzle having a discharge orifice diameter 14 of 2mm and a discharge orifice length 13 of 3 mm. The spinnability was good, and the yarn was broken 1 time during spinning of 1 ton. The single-hole discharge amount at this time was 1.0 g/min. The obtained undrawn yarn was combined to make a tow, which was stretched 2.6 times in a hot water bath at 90 ℃ to give a mechanical crimp, cut into a fiber length of 51mm, defibrated with a carding machine, and then made into a web with a cross web machine. Then, needling was performed to make 300g/m ² The fiber complex nonwoven fabric of (1). Then, the nonwoven fabric was impregnated with 13 wt% of a polyurethane composition (PU for short) and 87 wt% of a polyether polyurethane as a main componentIn a liquid composed of N, N' -Dimethylformamide (DMF), PU was solidified in an aqueous solution of 40% by weight of DMF, and then washed with water. Then, this nonwoven fabric was treated with trichloroethylene to elute and copolymerize PS, thereby obtaining a nanofiber structure having a thickness of about 1mm comprising PTT nanofibers and PU. One side of the artificial leather is polished by abrasive paper to enable the thickness to reach 0.8mm, the other side of the artificial leather is processed by a diamond sanding machine to form a nanofiber aggregate standing hair surface, and the artificial leather with the deer skin-like tone is obtained after dyeing and processing. Compared with the original artificial leather, the obtained artificial leather has better quality and style of softness, thinness and greasiness and rich elasticity.

The cross section of the obtained staple fiber was observed by TEM to show that the copoly-PS was sea (thin portion) and the copoly-PET was islands (thick portion). The obtained copolymerized PET island area polymer alloy fiber has the number average diameter of 50nm and the copolymerized PET is uniformly dispersed in nanometer size. These fibers had a single fiber fineness of 3.9 dtex, a strength of 1.3cN/dtex and an elongation of 25%.

Further, the polymer alloy fiber was sampled from the filament before cutting the fiber, circular-knitted in the same manner as in example 1, and then impregnated with trichloroethylene, and 99% or more of the copolymerization-PS as a sea component was eluted. Thereby obtaining a nanofiber aggregate. The number average single fiber diameter of the nanofibers reached 55nm (3X 1) as a result of analysis of the single fiber fineness variation of the nanofibers in the same manner as in example 10 ^-5 Decitex) to a fineness not originally present. The deviation of fineness of single fibers is also very small.

Example 52

Melt kneading was carried out in the same manner as in example 49 except that the PLA used in example 48 and the co-PS used in example 49 were used, the PLA content was 20% by weight, and the kneading temperature was 215 ℃ to obtain b ^* Polymer alloy sheet with value =2.

Melt spinning was carried out in the same manner as in example 1 except that the melt temperature was 230 ℃, the spinning temperature was 230 ℃ (nozzle surface temperature 215 ℃) and the spinning speed was 1200 m/min. In this case, a spinning nozzle having a discharge orifice diameter of 2mm and a metering portion having a diameter of 0.23mm above the nozzle orifice was used as the nozzle. The spinnability was good, and the yarn was broken 1 time during spinning of 1 ton. The single-hole discharge amount at this time was 0.7 g/min. The obtained undrawn yarn was subjected to a drawing heat treatment in the same manner as in example 49. The obtained drawn yarn was 111 dtex, 36 monofilaments, 1.3cN/dtex in strength, 35% in elongation, and 2.0% in U% =2.0%.

The cross section of the resulting polymer alloy fiber was observed by TEM to show that the co-PS was sea (thin portion) and the PLA was sea-island structure of islands (thick portion). The obtained polymer alloy fiber has the number average diameter of PLA island region of 40nm and PLA is uniformly dispersed in nanometer size.

The polymer alloy fiber thus obtained was circularly knitted in the same manner as in example 49, and then impregnated with trichloroethylene, whereby 99% or more of the copolymerization-PS as a sea component was eluted. A nanofiber assembly was obtained therefrom, and the number average single fiber diameter of nanofibers was 40nm (1X 10) as a result of analyzing the single fiber fineness variation of nanofibers in the same manner as in example 1 ^-5 Decitex) to achieve sufficient fineness. The deviation of the fineness of the single fiber is also very small.

Example 53

A circular knitted fabric comprising the nanofiber aggregate prepared in example 48 was dried at 110 ℃ for 1 hour, immersed in a treatment solution having the following composition for 2 hours to sufficiently impregnate the nanofiber aggregate with diphenyldimethoxysilane, the treated fabric was sufficiently washed with pure water, and then cured at 140 ℃ for 3 minutes to polymerize diphenyldimethoxysilane inside the nanofiber aggregate. The obtained mixture was washed 10 times at home and dried at 110 ℃ for 1 hour, and the weight of the obtained product was measured to increase by 38% as compared with that of the untreated product. Therefore, a mixed material in which diphenylsilicone is supported on a nanofiber aggregate can be obtained, and diphenylsilicone has good washing durability.

Composition of the treatment liquid:

diphenyl dimethoxy silane: 100ml of

Pure water: 100ml of

Ethanol: 300ml

10% hydrochloric acid: 50 drops of the Chinese medicinal composition

Example 54

The knitted fabric comprising the PBT nanofiber aggregate prepared in example 50 was allowed to adsorb natural oil components extracted from shark liver, that is, squalene having a skin-care effect due to moisture retention. The treatment conditions at this time were a mixture of squalene 60% and emulsifying dispersant 40%, dispersed in water at a concentration of 7.5 g/l, at a bath ratio of 1: 40, at a temperature of 130 ℃ and for a treatment time of 60 minutes. When the fabric was washed at 80 ℃ for 2 hours after the treatment, the amount of squalene adhered to the fabric reached 21% by weight. Then, the amount of squalene adhered after 20 home washes was 12 wt%, showing sufficient wash durability.

Socks were produced from circular knitted fabrics made of the squalene-processed PBT nanofiber aggregate, and wearing tests were conducted for 1 week on 10 subjects with severe heel dryness, and 8 subjects with mild dry skin were found. It is considered that squalene trapped in the nanofiber aggregate is slowly extracted by sweat of the subject and comes into contact with the skin.

Example 55

Melt spinning was carried out in the same manner as in example 48 except that the N6 content was set to 35%, to obtain a highly oriented undrawn yarn of N6/PLA polymer alloy of 400 dtex and 144 filaments. The highly oriented undrawn yarn was subjected to a drawing heat treatment in the same manner as in example 48. The drawn yarn obtained showed excellent properties of 288 dtex, 96 filaments, strength of 3.6cN/dtex, elongation of 40%, boiling water shrinkage of 9%, U% = 0.7%.

The cross section of the obtained polymer alloy fiber was observed by TEM to show that PLA was a sea (thin portion) and N6 was an island-in-sea structure of islands (thick portion), and a polymer alloy fiber in which N6 island regions had a number average diameter of 63nm and N6 was uniformly dispersed in a nano size was obtained. It was overfed by 15% and air-mixed with another prepared N6 false twist textured yarn of 165 dtex and 96 filaments. In addition, the mixed yarn is subjected to weak twist of 300 r/m, and S twist/Z twist double yarn is used as warp yarn and weft yarn to manufacture 2/2 twill fabric. The obtained twill fabric was subjected to alkali treatment in the same manner as in example 48 to obtain a denim of 150g/m comprising N6 nanofibers ² The curtain fabric. In the grey cloth for curtain, the N6 nano fiber is at the position of covering the normal N6 pseudo-low bank processing silk, and the nano fiber is mainly exposed on the surface of the fabric. Further, as a result of analyzing the variation in single fiber fineness of the nanofibers in the same manner as in example 1, the number average single fiber diameter of the nanofibers reached 67nm (4X 10) ^-5 Decitex) to a fineness not originally present. The single fiber fineness was 1X 10 ^-7 ～1×10 ^-4 The single fiber fineness ratio in the dtex range is 82%, particularly the single fiber fineness ratio with a single fiber diameter of 55 to 84nm is 60%, and the deviation of the single fiber fineness is particularly small. The N6 nanofibers had a strength of 2.0cN/dtex and an elongation of 40%.

The curtain fabric was subjected to silicone treatment in the same manner as in example 35, and as a result, the curtain fabric exhibited a delicate texture and a quality and texture like a wet human skin. In addition, the feeling of cold touch is also felt. Further, the moisture absorption rate (. DELTA.MR) was 4%, and the moisture absorption was sufficient, and the result of the acetic acid deodorization test was that the concentration was decreased from 100ppm to 1ppm for 10 minutes, indicating that the deodorant was excellent. In addition, the curtain made of the blank can obtain a fresh indoor environment and prevent condensation as a result of hanging 6 grass mats. The curtain is put into a washing net of a household washing machine for washing and dewatering without deformation, and shows good dimensional stability.

Possibility of industrial utilization

By using the nanofiber aggregate of the present invention, a fabric having a quality and style which has not been found in a normal ultrafine fiber and which has not been found before and a high-performance polishing cloth can be obtained.

The fibrous structure comprising the nanofiber aggregate of the present invention can be used as an intermediate product for silk, cotton (cotton), packaging materials, woven fabrics, knitted fabrics, felts, nonwoven fabrics, artificial leathers, sheets, and the like. Further, IT is preferable to use the fiber products as living applications such as clothing, clothing materials, interior products, vehicle interior products, living materials (wipers, cosmetics, health products, toys, etc.), environmental and industrial material products (building materials, polishing cloths, filter cloths, harmful substance removing products, etc.), IT parts (sensor parts, battery parts, robot parts, etc.), and medical products (blood filters, extracorporeal circulation columns, scaffolds (scaffold), wound dressings (wind dressing)), artificial blood vessels, sustained-release drugs, etc.

Claims

1. A nanofiber aggregate having a number average single fiber fineness of 1X 10 ^-7 ～2×10 ^-4 Single fiber fineness of single fiber with decitex of 60% or more than 60% is 1 × 10 ^-7 ～2×10 ^-4 In the dtex range and consisting of thermoplastic polymers.

2. The assembly of nanofibers according to claim 1, which are in the form of long fibers and/or in the form of woven filaments.

3. The assembly of nanofibers according to claim 1, wherein the number average single fiber fineness is 1 x 10 ^-7 ～1×10 ^-4 A single fiber having a fineness ratio of 60% or more in dtex of 1X 10 ^-7 ～1×10 ^-4 The decitex range.

4. The assembly of nanofibers according to claim 1, wherein the difference in fiber diameter between the single fibers constituting the assembly of nanofibers, the single fibers having a fineness ratio of 50% or more and 50% or more, is 30nm wide.

5. The assembly of nanofibers of claim 1, wherein the thermoplastic polymer is a condensation polymer.

6. The nanofiber assembly as claimed in claim 1, wherein the thermoplastic polymer has a melting point of 160 ℃ or higher.

7. The assembly of nanofibers of claim 1, wherein the thermoplastic polymer is selected from the group consisting of polyesters, polyamides and polyolefins.

8. The assembly of nanofibers according to claim 1, having a strength of 1cN/dtex or more.

9. The nanofiber assembly as claimed in claim 1, wherein the water absorption rate is 4% or more.

10. The assembly of nanofibers according to claim 1, wherein the water absorption swelling ratio in the filament length direction is 5% or more.

11. The assembly of nanofibers according to claim 1, wherein a functional agent is contained.

12. A fibrous structure comprising the nanofiber assembly according to claim 1.

13. The fiber structure according to claim 12, wherein the basis weight of the fiber is 20 to 2000g/m ² 。

14. The fiber structure according to claim 12, wherein a hollow portion of the hollow filament of the nanofiber aggregate is encapsulated.

15. The fiber structure according to claim 14, wherein the hollow fiber has a plurality of pores having a diameter of 100nm or less in the longitudinal direction.

16. The fiber structure according to claim 12, wherein a functional agent is contained.

17. The fibrous structure of claim 12 wherein the fibrous structure is selected from the group consisting of filaments, cotton, packaging, fabrics, knits, felts, nonwovens, artificial leather, sheets.

18. The fiber structure according to claim 17, wherein the fiber structure is a laminated nonwoven fabric in which a nonwoven fabric containing a nanofiber aggregate and another nonwoven fabric are laminated.

19. The fiber structure according to claim 12, wherein the fiber structure is a fiber product selected from clothing, clothing materials, interior products, vehicle interior products, living materials, environmental/industrial material products, IT parts, and medical products.

20. A liquid dispersion of the assembly of nanofibers of claim 1.

21. A polymer alloy fiber having a sea-island structure composed of 2 or more kinds of organic polymers having different solubilities, wherein the island component is composed of a hardly soluble polymer and the sea component is composed of a easily soluble polymer, the island region has a number average diameter of 1 to 150nm, the island region having an area ratio of 60% or more has a diameter of 1 to 150nm, and the island component is dispersed in the form of stripes.

22. The polymer alloy fiber according to claim 21, wherein the island regions have a number average diameter of 1 to 100nm, and 60% or more of the island regions have a diameter of 1 to 100nm in size.

23. The polymer alloy fiber according to claim 21, wherein the difference in diameter of the island region having an area ratio of 60% or more among the island regions contained in the polymer alloy fiber is in the range of 30 nm.

24. The polymer alloy fiber according to claim 21, wherein the island content is 10 to 30% by weight of the entire fiber.

25. The polymer alloy fiber according to claim 21, wherein the sea component is composed of a polymer that is easily soluble in an aqueous alkali solution or hot water.

26. The polymer alloy fiber according to claim 21, wherein the island component has a melting point of 160 ℃ or higher.

27. A polymer alloy fiber which is a composite fiber obtained by bonding the polymer alloy according to claim 21 and a polymer other than the polymer alloy.

28. The polymer alloy fiber according to claim 21, wherein a CR value as an index of crimp characteristics is 20% or more, or a crimp number is 5/25 mm or more.

29. The polymer alloy fiber according to claim 21, wherein the worsted specks are 5% or less.

30. The polymer alloy fiber according to claim 21, wherein the strength is 1.0cN/dtex or more.

31. A fiber structure comprising the polymer alloy fiber according to claim 21.

32. The fibrous structure of claim 31 wherein the fibrous structure is selected from the group consisting of filaments, cotton, packaging, fabrics, knits, felts, nonwovens, artificial leather, sheets.

33. A fiber structure according to claim 31, comprising polymer alloy fibers and other fibers.

34. The fiber structure according to claim 31, wherein the fiber structure is a fiber product selected from the group consisting of clothing, clothing materials, interior products, vehicle interior products, living materials, environmental/industrial material products, IT parts, and medical products.

35. A method for producing a polymer alloy fiber by melt-spinning a polymer alloy obtained by melt-mixing a poorly soluble polymer and a readily soluble polymer, wherein the following conditions (1) to (3) are satisfied:

36. The method of claim 35, wherein the melt-mixing is performed using a twin-screw extruder, and the length of the kneading section of the twin-screw extruder is 20 to 40% of the effective length of the screw.

37. The method for producing a polymer alloy fiber according to claim 35, wherein the melt-mixing is performed by a static mixer, and the number of divisions of the static mixer is 100 ten thousand or more, or 100 ten thousand or more.

38. The method of producing a polymer alloy fiber according to claim 35, wherein the shear stress between the melt-spun nozzle hole wall and the polymer is 0.2MPa or less, or 0.2MPa or less.

39. An organic/inorganic hybrid fiber comprising 5 to 95 wt% of the nanofiber aggregate according to claim 1, wherein at least a part of the inorganic substance is present in the inside of the nanofiber aggregate.

40. A fibrous structure comprising the organic/inorganic hybrid fiber according to claim 39.

41. A method for producing an organic/inorganic hybrid fiber according to claim 39, wherein the inorganic monomer is impregnated in the nanofiber aggregate and then polymerized.

42. A method of manufacturing a fibrous structure according to claim 40, wherein the fibrous structure comprising the nanofiber aggregate is impregnated with an inorganic monomer and then the inorganic monomer is polymerized.

43. A method for producing a hybrid fiber, comprising impregnating the nanofiber assembly of claim 1 with an organic monomer and then polymerizing the organic monomer.

44. A method for producing a fiber structure, wherein the fiber structure according to claim 12 is impregnated with an organic monomer and then the organic monomer is polymerized.