JPH08188967A - Hollow fiber and method for producing thereof - Google Patents

Abstract

PURPOSE: To obtain a hollow fiber capable of manifesting its function as well as enduring properties by filling a water insoluble polymer having a specific function into the hollow part in a good efficiency. CONSTITUTION: Method for producing this hollow fiber comprises forming plural connected through holes having 0.2-10μm width and 5-20μm length lying scattered from the surface to the hollow part of the fibers by knitting a tricot using polyester-based hollow multi-filaments, refining and preset-treating, and weight reduction-treating same with a hot sodium hydroxide solution for a short period, accommodating the tricot in a hermetically closable vessel and reducing pressure in the vessel, injecting a filling solution containing a water soluble monomer such as polyethylenedimethacrylate expressed by the formula (X is H or a 1-4C alkyl, Y is a 1-80C organic group), etc., and a polymerization initiator such as potassium persulfate, etc., into the vessel, again reducing the pressure to fill the filling solution into the hollow part through the above mentioned connected through holes, washing the surface of the fiber lightly with water, and then conducting the polymerization of the monomer to form a water insoluble polymer so as to make the polymer having >=1% void filling ratio, preferably >=3 % based on the hollow part to develop a moisture absorbing and static electricity controlling properties with a good enduring properties.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hollow fiber having a water-insoluble polymer in the hollow portion. More specifically, it can impart various functions to the fiber and is excellent in durability of the function. It relates to hollow fibers.

[0002]

2. Description of the Related Art Heretofore, there have been some proposals for hollow fibers in which a fiber has a communicating hole to the hollow portion and a functional substance is attached to the hollow portion.

For example, Japanese Patent Laid-Open No. 5-339878,
JP-A-6-17372 and JP-A-6-17373.
The publication discloses that a hollow synthetic fiber having a communication hole to the hollow portion on the surface of the fiber is impregnated with natural protein lactate in the hollow hole to insolubilize by crosslinking to improve moisture absorption durability. .

However, the natural protein solution generally has a high viscosity, and the aqueous solution sometimes gels.
It is extremely difficult to impregnate the hollow portion through the communication hole. On the other hand, when the natural protein is impregnated at a low concentration, the amount of the natural protein contained in the hollow portion becomes small and the level of the expressed function becomes insufficient.

On the other hand, in Japanese Unexamined Patent Publication (Kokai) No. 5-173167, a hollow having a split groove extending in the longitudinal direction of the fiber is formed by alkali-reducing the core-sheath type composite fiber and dissolving and removing the core. Disclosed is a hygroscopic fiber in which a hygroscopic agent formed of a monomer having a cloud point not higher than the glass transition point of a fiber-forming polymer is attached to the hollow part of the hollow fiber.

However, in the above method, it is difficult to completely dissolve and remove the core portion, the adhesion of the monomer becomes insufficient, and even if the core portion is dissolved and removed, the splitting is too large in width and length. Since the groove is formed, there is a problem that the hygroscopic agent falls off from the split groove at the time of washing and the like, resulting in poor durability.

[0007]

The object of the present invention is to efficiently allow an amount of a water-insoluble polymer capable of sufficiently exhibiting various functions to be present in the hollow portion of a hollow fiber having fine communication holes. It is an object of the present invention to provide a hollow fiber that sufficiently exhibits the function and has significantly improved durability, and a method for producing the hollow fiber.

[0008]

Means for Solving the Problems As a result of intensive studies for achieving the above object, the present inventors have found that a water-insoluble polymer is present in the hollow portion of a hollow fiber in which communication holes to the hollow portion are scattered on the fiber surface. It has been found that a desired hollow fiber can be obtained when the polymerization is carried out in the hollow portion after filling the monomer capable of forming γ, especially a water-soluble monomer.

That is, the present invention is a hollow fiber in which communication holes to the hollow portion are scattered on the surface of the fiber, and a non-water-soluble polymer polymerized from a water-soluble monomer is present in the hollow portion of the hollow fiber. The hollow fiber characterized by the following, and the hollow part of the hollow fiber in which communication holes to the hollow part are scattered on the fiber surface, a water-soluble monomer containing a polymerization initiator is suction-filled through the communication hole, and then the monomer Is a method for producing a hollow fiber.

The hollow fiber of the present invention means a hollow fiber composed of chemical fibers such as rayon and acetate, synthetic fibers such as polyester and nylon, and polyester hollow fibers are particularly preferred.

The polyester as used herein has terephthalic acid as a main dicarboxylic acid component, and at least one glycol, preferably at least one alkylene glycol selected from ethylene glycol, trimethylene glycol and the like as a main glycol component. For example, polyester.

If necessary, a stabilizer may be added to the polyester.
Antioxidant, flame retardant, antistatic agent, optical brightener, catalyst,
It may contain a coloring preventing agent, a heat-resistant agent, a coloring agent, inorganic particles and the like.

The hollow fiber can be produced by a conventionally known method, for example, the method described in Japanese Utility Model Publication No. 2-43879 can be arbitrarily adopted.

As a method of forming a connecting hole to the hollow portion on the surface of the fiber, for example, in the case of polyester fiber, a polyester obtained by copolymerizing an organic sulfonic acid compound is mixed and melt-spun to form a hollow fiber, By reducing the amount of alkali, it is possible to form communication holes (Japanese Patent Laid-Open No. Hei 1).
-20319 gazette etc.).

If high hollow fibers having a hollow ratio of 20% or more are treated with an alkali, the low orientation portions and / or the deformation strain concentrated portions along the longitudinal direction of the fibers can be formed without using an organic sulfonic acid compound. A communication hole can be formed as a removal mark.

The communicating hole preferably has a width of 0.2 to 10 μm and a length of 5 to 20 μm. When the width and the length of the communication hole are out of the above ranges, the water-soluble monomer may be insufficiently filled, or the water-insoluble polymer may be easily dropped off.

As a method for filling the hollow portion with the water-soluble monomer, the following method can be exemplified. A method in which a solution containing a water-soluble monomer and a polymerization initiator is applied onto hollow fibers and then heated. A method of immersing hollow fibers in a bath composed of a water-soluble monomer and a polymerization initiator, replacing air with an aqueous solution, and then heating. A method of immersing the hollow fiber in a bath composed of a water-soluble monomer and a polymerization initiator, squeezing with a mangle or the like to replace air with the aqueous solution, and then heating. A method in which a hollow fiber is placed in a closed container to reduce the pressure, air in the hollow portion is evacuated, and then an aqueous solution containing a water-soluble monomer and a polymerization initiator is injected into the container to be filled in the hollow and then heated.

The water-soluble monomer used in the present invention has a low viscosity and can be easily filled in the hollow portion through the fine communication holes scattered on the surface of the hollow fiber.
Moreover, it refers to a polymer capable of forming a water-insoluble polymer that exhibits functions such as antistatic property and hygroscopicity.

As such a monomer, a water-soluble monomer represented by the following general formula (I) is preferably exemplified.

[0020]

Embedded image

X in the monomer is hydrogen or an alkyl group having 1 to 4 carbon atoms, such as methyl group, ethyl group, n-propyl group, i-propyl group, n-butyl group and i-butyl. Group, sec-butyl group, tert-butyl group. Y is hydrogen or an organic group having 1 to 80 carbon atoms, preferably an aliphatic organic group, and examples thereof include 2-hydroxyethyl group, dimethylaminoethyl group, diethylaminoethyl group, (chlorinated) trimethylaminoethyl group,
Examples thereof include hydroxy polyethylene glycol group, methoxy polyethylene glycol group, acryloyl glyceryl group, methacryloyl glyceryl group, acryloyl polyethylene glycol group, methacryloyl polyethylene glycol group and the like.

Specific examples of these water-soluble monomers include, for example, methacrylic acid, 2-hydroxyethyl methacrylate, 2-hydroxyethyl acrylate, dimethylaminoethyl methacrylate, diethylaminoethyl methacrylate, methoxypolyethylene glycol methacrylate and dimethylaminoethyl methacrylate. Examples thereof include a graded salt, acryloyl glyceryl acrylate, acryloyl glyceryl methacrylate, methacryloyl glyceryl acrylate, and methacryloyl glyceryl methacrylate.

Since the above water-soluble monomer has no aromatic group, it has a low viscosity and easily penetrates into the hollow portion, and at the time of polymerization, it spreads over the entire inner wall of the hollow portion to form a polymer. Therefore, the polymer is extremely unlikely to drop off.

Two or more kinds of these monomers may be used at the same time.

Examples of the polymerization initiator include peroxides such as potassium persulfate, ammonium persulfate, hydrogen peroxide and benzoyl peroxide, cerium ammonium salts such as ceric ammonium sulfate and ceric ammonium nitrate, and α , Α′-azobisisobutyronitrile and the like.

The filling amount of these polymers in the hollow is required to be 1% or more, more preferably 3% or more, in terms of void occupancy.

If the void occupancy rate is less than 1%, the water-insoluble polymer may not adhere to the entire inner wall of the hollow portion, and the function may not be sufficiently exhibited.

On the other hand, the higher the void occupancy rate, the better the expression. However, when the polymer is filled more than necessary, the lightweight feeling of the hollow fiber is impaired, and therefore at most 8.
0% is sufficient.

It is also possible to mix a functional compound in these polymers.

[0030]

In the present invention, since the water-insoluble polymer is spread over the entire inner wall surface of the hollow part, the hollow part of the hollow fiber having the communication holes for the hollow part scattered on the fiber surface is filled. The durability of the function of the polymer is remarkably improved.

That is, in the present invention, since the low-viscosity water-soluble polymer is filled in the hollow portion of the hollow fiber, the filling proceeds extremely smoothly, and the water-soluble polymer spreads over the entire inner wall surface of the hollow portion. Polymerizes in the state to form a water-insoluble polymer.

Therefore, even if water penetrates into the hollow portion due to washing or the like, the above polymer does not elute, and even if a part of the polymer is peeled off from the inner wall surface of the hollow portion, If the united piece is smaller than the communication hole, it remains in the hollow portion, and the durability is significantly improved.

On the other hand, the above-mentioned JP-A-5-1731
In Japanese Patent Publication No. 67, the split grooves formed in the longitudinal direction of the fiber are excessively large, and the hygroscopic agent filled in the hollow easily comes off due to washing or the like.

[0034]

EXAMPLES The present invention will be described below with reference to examples.
The present invention is not limited to these examples.

[Example 1] Polyethylene terephthalate having an intrinsic viscosity of 0.61 was melted, and an undrawn yarn of hollow fiber having a hollow ratio of 40% was obtained using the hollow spinneret shown in Fig. 1. Next, this unstretched yarn is stretched to form a hollow hollow with 50 denier and 20 filaments (titanium oxide amount: 0.3% by weight).
A multifilament yarn was obtained.

Tricots were prepared, refined and preset according to a conventional method. The obtained cloth is sodium hydroxide 5
The treatment was carried out in hot water (105 ° C.) of 0 g / l for a short time (10 minutes) to obtain a weight loss rate of 20%.

The multifilament yarn was taken out from the obtained cloth and the surface thereof was observed by an electron microscope. As a result, the width was 0.2 to 2.0 μm and the length was 10 per 100 μm in the fiber axis direction.
At least one micro-groove of ˜150 μm was observed.

Next, the cloth is put in a closed container, the pressure in the container is reduced to 0.004 mmHg by using a rotary pump, and then PEG having the structure of the formula (II) is put in the container.
-Dimethacrylate; 10 parts by weight, potassium persulfate;
A filling liquid consisting of 0.1 parts by weight of water and 89.9 parts by weight of water was injected.

After the injection, a reduced pressure state was further maintained for 10 minutes using a rotary pump. At this time, the pressure in the container is 0.
It was 2 mmHg. Next, for the purpose of removing the excess amount of the filling liquid adhering to the surface of this cloth, it was lightly washed with normal temperature water, and then heated at 100 ° C. for 20 minutes with an atmospheric steamer.

The hollow part in the fiber of the obtained cloth has PE
A polymer structure of G-dimethacrylate was present as shown in FIG. 2, and the void occupancy rate was about 16%.

Further, this fabric had a soft texture and showed high moisture absorption and antistatic property as shown in Table 1. This fabric was excellent in washing durability, and the moisture absorption rate and the antistatic property were the same as those of the initial stage even after 20 times of washing.

[0042]

[Chemical 4]

[Example 2] PEG-dimethacrylate; 20 parts by weight, potassium persulfate; 0.1 parts by weight,
Water: The same operation as in Example 1 was performed except that the amount was 79.9 parts by weight.

PE in the hollow part of the fiber of the obtained cloth.
A polymer structure of G-dimethacrylate was present and the void occupancy was about 33%. In addition, this fabric had a soft texture similar to that of Example 1 and, as shown in Table 1, showed a high moisture absorption rate with good durability and antistatic property.

[Example 3] PEG-dimethacrylate; 30 parts by weight, potassium persulfate; 0.1 part by weight,
Water: The same operation as in Example 1 was performed except that 69.9 parts by weight was used.

PE in the hollow part of the fiber of the obtained cloth
A polymer structure of G-dimethacrylate was present and the void occupancy was about 44%. In addition, this fabric had a soft texture similar to that of Example 1 and, as shown in Table 1, showed a high moisture absorption rate with good durability and antistatic property.

[Example 4] PEG-dimethacrylate; 50 parts by weight, potassium persulfate; 0.1 parts by weight,
Water: The same operation as in Example 1 was performed except that the amount was 49.9 parts by weight.

PE in the hollow part of the fiber of the obtained cloth
A polymer structure of G-dimethacrylate was present and the void occupancy was about 67%. In addition, this fabric had a soft texture similar to that of Example 1 and, as shown in Table 1, showed a high moisture absorption rate with good durability and antistatic property.

[Embodiment 5] The monomer of the filling liquid is represented by the formula (III
The same operation as in Example 3 was performed except that the PEG-diacrylate having the structure of 1) was used.

PE in the hollow part of the fiber of the obtained cloth
A polymer structure of G-diacrylate was present and the void occupancy was about 40%. In addition, this fabric had a soft texture similar to that of Example 1 and, as shown in Table 1, showed a high moisture absorption rate with good durability and antistatic property.

[0051]

Embedded image

Example 6 The monomer of the filling liquid is represented by the formula (IV)
The same operation as in Example 3 was performed except that methoxy polyethylene glycol methacrylate having the structure of was used.

A polymer structure of methoxypolyethylene glycol methacrylate was present in the hollow part of the fiber of the obtained cloth, and the void occupancy rate was about 37%. Also,
Similar to Example 1, this fabric had a soft texture and, as shown in Table 1, exhibited a high moisture absorption rate with good durability and antistatic property.

[0054]

[Chemical 6]

[Embodiment 7] Instead of performing the filling treatment under reduced pressure in Embodiment 3, the cloth is dipped in a solution of the monomer, and is squeezed at a pressure of 5 kg / cm ² using mangle in the liquid to obtain air. The filling liquid was replaced. Next, for the purpose of removing the excess amount of the filling liquid adhering to the surface of this cloth, it was lightly washed with normal temperature water, and then heated at 100 ° C. for 20 minutes with an atmospheric steamer.

In the hollow part of the fiber of the obtained cloth, the polymer structure of the formula (II) is present, and the void occupancy rate is about 33%.
Met. In addition, this fabric had a soft texture similar to that of Example 1 and, as shown in Table 1, showed a high moisture absorption rate with good durability and antistatic property.

[Example 8] Instead of performing the filling treatment under reduced pressure in Example 3, the cloth is dipped in a solution of the monomer, and a color pet dyeing machine (12LMP-E II manufactured by Nippon Dyeing Machinery Co., Ltd. is used.
Using I), the mixture was heated and shaken at 40 ° C. for 20 minutes to replace the air with the filling liquid. Next, for the purpose of removing the excess amount of the filling liquid adhering to the surface of this cloth, lightly wash with normal temperature water,
Then, the mixture was heated at 100 ° C. for 20 minutes with an atmospheric pressure steamer.

In the hollow part of the fiber of the obtained cloth, the polymer structure of the formula (II) is present, and the void occupancy is about 39%.
Met. In addition, this fabric had a soft texture similar to that of Example 1 and, as shown in Table 1, showed a high moisture absorption rate with good durability and antistatic property.

Comparative Example 1 PEG having the structure of formula (II)
-Dimethacrylate; 30 parts by weight, potassium persulfate;
10 parts by weight of a monomer solution of 0.1 parts by weight and 69.9 parts by weight of water
The polymer obtained by heating at 0 ° C. for 20 minutes with an atmospheric pressure steamer to polymerize was dried to obtain fine particles having an average particle size of 10 μm, and the same operation as in Example 1 was performed using a filling liquid of 30% in terms of solid content. .

No polymer structure of the monomer was present in the hollow portion of the fiber of the obtained cloth, and as shown in Table 1, low hygroscopicity and antistatic property were exhibited.

[Comparative Example 2] PEG having the structure of formula (II)
-The same operation as in Comparative Example 1 was performed except that diacrylate was used.

No polymer structure of the monomer was present in the hollow portion of the fiber of the obtained cloth, and as shown in Table 1, low hygroscopicity and antistatic property were exhibited.

[Comparative Example 3] The same operation as in Comparative Example 1 was carried out except that methoxypolyethylene glycol methacrylate having the structure of the formula (IV) was used.

No polymer structure of the monomer was present in the hollow part of the fiber of the obtained cloth, and as shown in Table 1, low hygroscopicity and antistatic property were exhibited.

[0065]

[Table 1]

The methods for measuring each physical property in the examples are as follows.

(1) Moisture Absorption Rate The sample was predried at 50 ° C. × 2 Hr, conditioned at 20 ° C. for 3 days and nights, and then absolutely dried at 105 ° C. × 2 Hr (the weight at this time was W ₀ ). Next, 2Hr in a desiccator at 20 ° C x 90RH
After the addition, the weight (W ₁ ) was measured and the moisture absorption rate was calculated by the following formula.

[0068]

[Equation 1]

(2) Friction electrification voltage According to JIS L-1094 8.2 B method, a rotary static tester (Kyoto University, Kaken type) was used. The rubbing cloth was a cotton wire and the measurement conditions were 20 ° C. and 40% RH. The smaller the frictional electrification voltage is, the better the antistatic property is, and if it is 1.5 KV or less, it can be developed as a practical product.

(3) Washing durability According to JIS L-1018-77 6.36 H method,
The washing was repeated 20 times.

(4) Porosity occupancy rate A cross section was photographed by an electron microscope, and the void occupancy rate was calculated by the following formula, where M ₁ is the hollow cross-sectional area of the hollow fiber and M ₂ is the cross-sectional area of the polymer structure in the hollow. did.

[0072]

[Equation 2]

[0073]

EFFECTS OF THE INVENTION According to the present invention, a hollow fiber having an excellent expression function and durability can be obtained.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing an example of a spinneret for spinning a round hollow fiber.

FIG. 2 is a cross-sectional view of a hollow fiber containing a water-insoluble polymer.

[Explanation of symbols]

S _{1 to} S ₄ Slits constituting the hollow fiber spinneret C Voids between slit ends S ′ _{1 to} S ′ ₄ Polymers constituting the thin-skin portion of the hollow fibers G _{1 to} G ₄ Communication holes communicating with the hollow portions of the hollow fibers P Water-insoluble polymer

Claims (7)

[Claims] 1. A hollow fiber in which communication holes to the hollow part are scattered on the surface of the fiber, and a non-water-soluble polymer formed from a water-soluble monomer is present in the hollow part of the hollow fiber. Hollow fiber to do. 2. The hollow fiber according to claim 1, wherein the communicating hole has a width of 0.2 to 10 μm and a length of 5 to 20 μm. 3. The hollow fiber according to claim 1, wherein the water-soluble monomer is a monomer represented by the following general formula (I). Embedded image (Here, X represents hydrogen or an alkyl group having 1 to 4 carbon atoms, and Y represents an organic group having 1 to 80 carbon atoms.) 4. The hollow fiber according to claim 1, wherein the water-soluble monomer is a monomer represented by the following general formula (I). Embedded image (Here, X represents hydrogen or an alkyl group having 1 to 4 carbon atoms, and Y represents an aliphatic organic group having 1 to 80 carbon atoms.) 5. The hollow fiber according to claim 1, wherein the water-insoluble polymer has a void occupancy rate of 1% or more with respect to the hollow portion. 6. The water-insoluble polymer has a void occupancy rate of 3% or more with respect to a hollow portion, 1, 2, 3, 4 or 5.
The hollow fiber described. 7. A water-soluble monomer containing a polymerization initiator is suction-filled through the communication hole into the hollow part of the hollow fiber in which communication holes to the hollow part are scattered on the fiber surface, and then the monomer is polymerized. A method for producing a hollow fiber, comprising: