JP2001055628A - Production of polyurethane fiber - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain polyurethane fiber excellent in all of antistatic function, water absorbability, mechanical strength and stretchability without needing cumbersome after-treatment. SOLUTION: This elastic polyurethane fiber is obtained by mixing (A) a thermoplastic polyurethane resin produced by reaction between an organic diisocyanate such as dicyclohexylmethane diisocyanate and a polyethylene glycol- based polymeric diol with (B) a polyurethane resin produced by dissolving in a polar organic solvent a product formed by reaction between an organic diisocyanate such as diphenylmethane diisocyanate, a chain extender such as ethylenediamine and a high molecular diol such as polytetramethylene glycol or polyester glycol at a weight ratio A/B of (0.5:9.5) to (7:3) followed by spinning the resultant mixture.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to clothing or medical aids worn in contact with the body such as inner foundations, pantyhose, socks, gloves, supporters, bandages, etc., ski wear, golf wear, etc. The present invention relates to a method for producing a polyurethane fiber suitable for sports equipment.

[0002]

2. Description of the Related Art Fibers used in clothing used in contact with the body are required to have fiber strength and elasticity. Conventionally, polyurethane fibers called spandex have been used as fibers having such functions or characteristics.

[0003] Spandex is defined as a synthetic fiber in which at least 85% by weight of the fiber-forming substance is formed from a long-chain polymeric material having a segmented polyurethane. Since spandex is excellent in water absorption,
Although used for clothing, medical aids and sporting goods used in contact with the body, the water absorption of spandex is still insufficient compared to the water absorption of natural fibers.

For this reason, various treatments for imparting water absorbency to polyurethane fibers have been performed. For example, a polyurethane fiber is immersed in a solution of a water-soluble wool protein, or a polyurethane fiber is provided with a water-soluble protein having high water absorption (see JP-A-9-49171 and JP-A-9-228249). ).

[0005] For the same purpose, a highly water-absorbing surfactant, ultra-fine cellulose powder, magnesium salt or the like is added to polyurethane fibers, or a highly water-absorbing substance is dispersed in a polyurethane resin solution to prepare a yarn or the like. It has been proposed to attach it to the surface of a fibrous structure by a wet coagulation method. Further, it has been proposed to mix and add these highly water-absorbing substances to a water-soluble substance and to elute the water-soluble substance into a porous fiber structure by a wet coagulation method.

[0006] However, these known techniques attach and add a highly water-absorbing substance to the polyurethane fibers and treat them, so that sufficient water absorption required for clothing and the like cannot be obtained. However, there were drawbacks in that the durability of water absorption was low and the fiber strength was low.

[0007] Further, these known techniques have a drawback that the polyurethane fiber is subjected to a post-treatment step after the polyurethane fiber is manufactured so as to improve the water absorption, so that the process is complicated and expensive. Was.

The present inventors have proposed a method for producing a polyurethane fiber excellent in antistatic function, water absorption and fiber strength in order to overcome these disadvantages of the prior art (Japanese Patent Application No. 10-330). , No. 174)

This method comprises the steps of reacting a thermoplastic polyurethane resin (A) obtained by reacting an organic diisocyanate such as dicyclohexylmethane diisocyanate, a chain extender, and a polyethylene glycol polymer diol with:
The thermoplastic polyurethane resin (B) obtained by reacting an organic diisocyanate such as dicyclohexylmethane diisocyanate with a chain extender and a polymer diol other than a polyethylene glycol type is (A) / (B) = 1 / 9-
In this method, polyurethane fibers are produced by mixing at a weight ratio of 5/5 and then spinning the mixture.

This polyurethane fiber has a low volume resistivity, a high antistatic function, a large fiber strength, improved spinnability, a high water absorption, and is suitable for use in clothing such as underwear. Have been.

In order to impart the fiber strength to the polyurethane fiber in addition to the water absorption, in addition to the polyethylene glycol-based polymer diol (eg, polyethylene glycol), a non-polyethylene glycol-based polymer diol (eg, polystyrene) is used. Ether diol, polyester diol, etc.), but the polyurethane fibers proposed by the present inventors have not synthesized these polymer diols in one reaction system, but (A) (B)
By synthesizing the two thermoplastic polyurethane resins in separate reaction systems, high water absorption and fiber strength are imparted while maintaining the characteristics of these two polymer diols.

However, since this polyurethane fiber has a linear molecular structure in order to provide high fiber strength,
In particular, the elastic recovery after the elongation of the fiber decreased, and a polyurethane fiber excellent in all of the antistatic function, water absorption, fiber strength and elasticity could not be obtained.

[0013]

SUMMARY OF THE INVENTION The object of the present invention is to provide an excellent antistatic function, water absorption, fiber strength and stretchability without the need for complicated post-treatments. It is an object of the present invention to provide a method for producing a polyurethane fiber having durability in the above properties.

[0014]

According to one aspect of the present invention, there is provided a polyurethane resin (A) and (B) as follows: (A) / (B) = 0.5 / 9.5-7 / It is another object of the present invention to provide a method for producing a polyurethane fiber, comprising mixing the mixture at a weight ratio of 3 and then spinning the mixture to produce a polyurethane fiber. (A) a thermoplastic polyurethane resin obtained by reacting an organic diisocyanate (A1) with one or more polymer diols (A2) selected from the group consisting of polyethylene glycol and poly (oxyethylene-oxyalkylene) glycol . (B) a group consisting of at least one organic diisocyanate (B1) selected from the group consisting of diphenylmethane diisocyanate, tolylene diisocyanate and hexamethylene diisocyanate, a chain extender (B2), polytetramethylene glycol and polyester glycol A polyurethane resin obtained by dissolving a product produced by reacting at least one polymer diol (B3) selected from the group consisting of: a polar organic solvent (B4).

As the organic diisocyanate (A1),
It can be selected from dicyclohexyl methane diisocyanate, hexamethylene diisocyanate, diphenyl methane diisocyanate, etc., and a chain extender (B
2) can be selected from ethylenediamine, hydrazine, diamine and the like.

In a typical method for producing a polyurethane fiber of the present invention, the thermoplastic polyurethane resin (A) comprises, for example, dicyclohexylmethane diisocyanate and / or diphenylmethane diisocyanate as an organic diisocyanate (A1) and a polymer diol (A2). Is a thermoplastic polyurethane resin obtained by reacting with polyethylene glycol as a polyisocyanate. The polyurethane resin (B) is a diphenylmethane diisocyanate as an organic diisocyanate (B1) and a chain extender (B2).
And polytetramethylene glycol as a polymer diol (B3), and a product obtained by dissolving the product in dimethylformaldehyde as a polar organic solvent (B4). .

The thermoplastic polyurethane resin (A) comprises an organic diisocyanate (A1) and a polymer diol (A2).
Can further be reacted with a chain extender (A3).

As described above, in order to obtain the polyurethane resin (B), the organic diisocyanate (B1) is selected from diphenylmethane diisocyanate, tolylene diisocyanate and hexamethylene diisocyanate, and the chain extender (B2) is formed from ethylenediamine and hydrazine. The high molecular diol (B3) is selected from polytetramethylene glycol and polyester glycol, which can improve the elasticity of the polyurethane fiber by changing the polyurethane fiber from a linear structure to a network structure. In addition, since the network structure of the fiber improves the elasticity without lowering the fiber strength, the strength of the polyurethane fiber can be maintained.

In order to obtain the thermoplastic polyurethane resin (A), the organic diisocyanate (A1) is selected from dicyclohexylmethane diisocyanate, hexamethylene diisocyanate and diphenylmethane diisocyanate, and the high molecular diol (A2) is polyethylene glycol. And poly (oxyethylene-oxyalkylene) glycol, which is exactly the same as the resin component (A) of the polyurethane fiber previously proposed by the present inventors, and maintains the high water absorption of the polyurethane fiber. can do.

The mixing ratio of the thermoplastic polyurethane resin (A) and the polyurethane resin (B) is (A) / weight ratio.
(B) = 0.5 / 9.5-7 / 3, but when (A) is large, water absorption is increased, and when (B) is large, stretchability is increased. It is preferable to select from the above range accordingly.

[0021]

BEST MODE FOR CARRYING OUT THE INVENTION Next, embodiments of the present invention will be described in detail.
As already described, basically, the following polyurethane resins (A) and (B) are obtained by dividing (A) / (B) = 0.5 /
Mixing at a weight ratio of 9.5 to 7/3, and then spinning the mixture to produce polyurethane fibers.

The polyurethane resin (A) comprises at least one organic diisocyanate (A1) selected from dicyclohexylmethane diisocyanate, hexamethylene diisocyanate and diphenylmethane diisocyanate;
1 selected from the group consisting of polyethylene glycol and poly (oxyethylene-oxyalkylene) glycol
It is a thermoplastic polyurethane resin obtained by reacting at least one kind of polymer diol (A2). If necessary, a chain extender (A3) is added for reaction.

The organic diisocyanate (A1) used in the synthesis of the thermoplastic polyurethane resin (A) may be the above-mentioned dicyclohexylmethane diisocyanate, hexamethylene diisocyanate, diphenylmethane diisocyanate alone or a mixture of two or more thereof. Although possible, dicyclohexylmethane diisocyanate or diphenylmethane diisocyanate alone is preferred.

The polymer diol (A2) used for synthesizing the thermoplastic polyurethane resin (A) includes polyethylene glycol, poly (oxyethylene-oxyalkylene)
Glycol or a mixture thereof, but polyethylene glycol having an average molecular weight of 500 to 8000 is preferred. As the poly (oxyethyleneoxyalkylene) glycol, those which do not impair the water absorption, such as a copolymer (glycol) of ethylene oxide and another alkylene oxide, are used.

When a chain extender (A3) is used in the synthesis of the thermoplastic polyurethane resin (A), the chain extender (A3) may be ethylene glycol, 1,2-propadiol, 1,3-propadiol. , Diethylene glycol, 1,4-butanediol, neo-p-pentyl glycol, 1,6-hexanediol, 1,9-nonanediol, bis-β-hydroxyethoxybenzene, 3-methyl-1,5-pentanediol, And compounds having a molecular weight of less than 400, such as 1,4-cyclohexanedimethanol, which may be used alone or in combination of two or more.

The polyurethane resin (B) is at least one organic diisocyanate (B1) selected from the group consisting of diphenylmethane diisocyanate, tolylene diisocyanate and hexamethylene diisocyanate, and one type selected from ethylenediamine, hydrazine, diamine and the like. A product formed by reacting the above chain extender (B2) with one or more polymer diols (B3) selected from the group consisting of polytetramethylene glycol and polyester glycol is converted to a polar organic solvent ( B4).

The organic diisocyanate (B1) used in the synthesis of the thermoplastic polyurethane resin (B) can be diphenylmethane diisocyanate, tolylene diisocyanate, hexamethylene diisocyanate or a mixture thereof, but diphenylmethane diisocyanate alone is preferred.

Thermoplastic polyurethane The chain extender (B2) used in the synthesis of this resin (B) can be either ethylenediamine (molecular weight 60) or hydrazine (molecular weight 32) or a mixture thereof. Is preferred.

Thermoplastic polyurethane The high molecular weight diol (B3) used in the synthesis of the resin (B) has a molecular weight of at least 4,000, preferably 500 to 12,000, and is preferably polytetramethylene glycol, polyester glycol, polytetraester glycol or a mixture thereof. It can be a mixture, of which polytetramethylene glycol is particularly preferred.

The polar organic solvent (B4) used for synthesizing the polyurethane resin (B) can be dimethylformaldehyde or dimethylacetamide.

When synthesizing the thermoplastic polyurethane resin (A), the polymer diol (A2) and the chain extender (A3)
The ratio (R value) of the number of moles of isocyanate groups of the organic diisocyanate (A1) to the total number of moles of active hydrogen groups of R is 0.
The reaction is carried out so as to be 7 to 1.3, preferably 0.9 to 1.1. Chain extender (A3) and polymer diol (A
2) means that the ratio (R 'value) of the number of moles of active hydrogen groups of the chain extender to the number of moles of active hydrogen groups of the polymer diol (A2) is 0.1.
Preferably, the reaction is performed so that

When synthesizing the thermoplastic polyurethane resin (B), the ratio (R value) of the number of moles of isocyanate groups of the organic diisocyanate (B1) to the number of moles of active hydrogen groups of the polymer diol (B3) is 1.0 / (2.0-4.
0), preferably 1.0 / 2.0 to form a prepolymer. That is, the organic diisocyanate (B1) and the polymer diol (B3) are enriched in the organic diisocyanate and reacted to form a prepolymer.

The chain extender (B2) has a function of adding an organic diisocyanate (B1) in an amount equivalent to an equimolar ratio of NCO / NH ₂ with respect to the excess organic diisocyanate (B1) to extend the chain. The organic diisocyanate (B1) a polymeric diol (B3) and NCO prepolymers obtained by reacting equivalent relative chain extender of (B2) NH _2, i.e. NCO / N
H ₂ is in the range of 1.3 to 0.7 / 0.7 to 1.3, preferably 1/1.

The mixing ratio of the polyurethane resins (A) and (B) is in the range of 0.5 / 9.5 to 7/3 by weight, preferably 0.5 / 9.5 to 5/5. Set in range.
The weight ratio of the polyurethane resins (A) and (B) is 0.5 /
If it is less than 9.5, that is, if the weight ratio of the thermoplastic polyurethane resin (A) is less than 5%, the water absorption required for clothing or the like cannot be obtained, and the polyurethane resin (A) and ( B) is greater than 7/3, that is, the thermoplastic polyurethane resin (A) has a weight ratio of 7
If it is larger than 0%, the fiber strength and elasticity of the polyurethane fiber become unsatisfactory.

The thermoplastic polyurethane resin (A) can be produced by a one-shot method, a prepolymer method, a batch reaction method, a continuous reaction method, a kneader method, or the like. For example, to describe a case where the thermoplastic polyurethane resin (A) is produced by a kneader method, a polymer diol (A2) and a chain extender (A3) (when a chain extender is added) are charged into a kneader, and the temperature is raised to 80 ° C. After heating, the organic diisocyanate (A1) is charged, reacted for 10 to 60 minutes, and cooled to produce the thermoplastic polyurethane resin (A). The thermoplastic polyurethane resin (A) thus obtained is in the form of powder or block, which is dissolved in a polar organic solvent to form a dope.

On the other hand, the polyurethane resin (B) can be produced by the same method as that for the thermoplastic polyurethane resin (A). The polymer diol (B3) and the organic diisocyanate (B1) are charged and uniformly mixed, and reacted at 100 ° C. for several hours to obtain a prepolymer. This is dissolved in a polar organic solvent to form a uniform solution, and a chain extender is slowly added thereto to produce a polyurethane resin (B). The polyurethane resin (B) thus obtained is in a doped state.

These polyurethane resins (A) and (B)
Are mixed at a weight ratio of 0.5 / 9.5 to 7/3 to form a spinning solution. Thereafter, the spinning solution is spun into a polyurethane fiber monofilament by a wet or dry spinning method including a nozzle head and a solvent removing means.

In producing the polyurethane resins (A) and (B) used in the present invention, a catalyst can be used if necessary. Examples of the catalyst include amines such as triethylamine, triethylenediamine, N-methylimidazole, N-ethylmorpholine, 1,8-diazabixiro-5,4, O-undecene- (DBU), potassium acetate, and stannasoct. Organic metals such as ethate and dibutyltin dilaunate, and phosphorus compounds such as tributylphosphine, phosphorene and phosphorene oxide are used.

In the method of the present invention, other additives can be added to the polyurethane resins (A) and (B) as required for the purpose of adding other functions to the polyurethane fiber.
For example, antioxidants, ultraviolet absorbers, heat resistance improvers, plasticizers, lubricants, antistatic agents, conductivity-imparting agents, coloring agents, inorganic or organic fillers, fibrous reinforcing agents, hydrolysis inhibitors, A reaction retarder and the like can be added.

The method of the present invention comprises the steps of:
Using a mixture (fibrous material) of (B) and other additives,
It can be manufactured by a known polyurethane elastic fiber spinning method such as a wet spinning method and a dry spinning method.

The most significant feature of the present invention is that when the polyurethane resin (B) is composed of the above specific components, the polyurethane fibers can be changed from a linear structure to a network structure to improve the stretchability of the polyurethane fibers. It is. In addition, since the network structure of the fibers improves the elasticity without lowering the fiber strength, the fiber strength of the polyurethane fiber can be advantageously maintained. On the other hand, the thermoplastic polyurethane resin (A) imparts high water absorption to the polyurethane fiber. Therefore, by using these polyurethane resins (A) and (B) together, clothing and medical products used in contact with the body can be used. Water absorption, fiber strength and elasticity can be imparted to textiles such as auxiliary articles and sportswear. Further, these resin components (A) and (B)
As described later with reference to the examples, the polyurethane fiber containing can reduce the volume resistivity value, and thus can maintain the antistatic function required for clothing. Can be maintained.

The mixing ratio of the thermoplastic polyurethane resin (A) and the polyurethane resin (B) is, as described above,
The weight ratio is (A) / (B) = 0.5 / 9.5 to 7/3. When the amount of the resin (A) is large, the water absorption increases, and when the amount of the resin (B) is large, the elasticity is high. Is selected in the above range according to the use of the polyurethane fiber.

[0043]

EXAMPLES Next, examples (specific examples) of the present invention will be described together with comparative examples. In these examples, "parts" means "parts by weight", and "%" means "parts by weight". % ".

(Example 1) First, a method for synthesizing one thermoplastic polyurethane resin (A) for a polyurethane fiber will be described. In a reaction vessel having a stirrer, polyethylene glycol (Toho Kagaku) is used as a polymer diol (A2). PEG2000 manufactured by K.K., hydroxyl value 56.4 mgKOH
G) of 100 parts, 13.5 parts of 1,4-butanediol as a chain extender (A3), 0.84 parts of Irganox 1010, and 0.42 of Tinuvin P as an ultraviolet absorber
After the reaction temperature was adjusted to 100 ° C., normal temperature 4,4′-diphenylmethane diisocyanate was used as the organic diisocyanate (A1).
5 parts were added and a urethanization reaction was performed. The reactant was poured onto the vat and solidified. This solid was aged in an electric furnace at 80 ° C. for 24 hours, and then the solid was pulverized to obtain a powdery thermoplastic polyurethane resin (A). 100 parts of this thermoplastic polyurethane resin was charged into a dissolution vessel having a stirrer, and dimethylformamide 40 was used as an organic solvent.
After adding 0 parts, the mixture was gradually heated with stirring, and about 2 hours after the temperature was raised to 80 ° C., 9000 cps / 25.
A dope for a polyurethane fiber having a viscosity of ° C. (a dope-like thermoplastic polyurethane resin (A) -hereinafter referred to as a dope (1A)) was obtained.

Next, a method for synthesizing the other polyurethane resin (B) for the polyurethane fiber will be described. In a reaction vessel having a stirrer, polytetramethylene ether glycol (Hodogaya Chemical Co., Ltd.) is used as the polymer diol (B3). PTG1000, hydroxyl value 112mgKOH.
g), 100 parts of diphenylmethane diisocyanate as an organic diisocyanate (B1), and 0.7 parts of tinuvin 326 as an ultraviolet absorber were added and uniformly mixed, and reacted at a reaction temperature of 100 ° C. for 3 hours. The prepolymer thus obtained had an NCO equivalent of 750. To this prepolymer, 700 parts of dimethylformamide was added as a polar organic solvent, followed by stirring to obtain a uniform solution. 25 parts of ethylenediamine as a chain extender (B2) is slowly added to this homogeneous solution with stirring, and a dope for polyurethane fibers (a dope-like thermoplastic polyurethane resin (B) —hereinafter referred to as a dope (1B)).
I got

Finally, a method for producing polyurethane fibers from the dope (1A) (1B) for polyurethane fiber obtained by the above-mentioned method will be described. 375 g of polyurethane fiber dope A is added to 875 g of polyurethane fiber dope A. The dope B for fiber was added, and these were uniformly stirred to obtain a mixed dope (spinning solution) for polyurethane fiber. The mixing ratio of this mixed dope was (1A) / (1B) = 3/7.
The spinning solution is extruded into a strand form from a nozzle head of a single screw extruder, and a hot air stream of about 200 ° C. is blown onto the strand to blow off dimethylformamide, an organic solvent, to produce a 50 denier short yarn (polyurethane fiber monofilament). Manufactured.

(Example 2) The thermoplastic polyurethane resin (A) was obtained by the same method as in Example 1 (this is referred to as dope (2A)), but the polyurethane resin (B) was obtained by the following method. Was. That is, in a reaction vessel having a stirrer, polyethylene glycol (# 6000 manufactured by NOF Corporation, hydroxyl value: 12.5 mgKOH) was used as the polymer diol (B3).
/ G) as a chain extender (B2),
1.9 parts of butanediol, 0.84 parts of Irganox 1010 and 0.42 of Tinuvin P as an ultraviolet absorber
After the reaction temperature was adjusted to 100 ° C., 4,4 ′ was obtained as the organic diisocyanate (B1).
8.5 parts of diphenylmethane diisocyanate were added,
A urethanation reaction was performed. The reactant was poured onto the vat and solidified. This solid was aged in an electric furnace at 80 ° C. for 24 hours, and then the solid was pulverized to obtain a flake-like polyurethane resin (B). 100 parts of this polyurethane resin (B) is charged into a dissolution vessel having a stirrer, and 400 parts of dimethylformamide is added as an organic solvent.
The mixture was gradually heated with stirring, and about 2 hours after the temperature was raised to 80 ° C., a dope for a polyurethane fiber having a viscosity of 3000 cps / 25 ° C. (a dope-like polyurethane resin (B) —hereinafter referred to as a dope (2B)) was obtained. Was. The method of producing polyurethane fibers from the dope (2A) (2B) for polyurethane fibers has exactly the same steps and the same mixing ratio as in Example 1, and therefore the description thereof is omitted.

Example 3 A polyurethane resin was synthesized in exactly the same manner as in Example 1 except that the mixing ratio was (A) / (B) = 4/6. Polyurethane fibers were produced in the same manner as in Example 1.

Example 4 A polyurethane resin was synthesized in exactly the same manner as the polyurethane resins (A) and (B) of Example 2, except that the mixing ratio was (A) / (B) = 2/8. Polyurethane fibers were produced in the same manner as in Example 2.

(Comparative Example and Commercial Product) A polyurethane fiber was produced in the same manner as in Example 1 by using the spinning solution comprising only the thermoplastic polyurethane resin (A) of Example 1, and this was used as a comparative example. The commercial product was Fujibo Spandex composed of polytetramethylene glycol / diphenylmethane diisocyanate / ethylenediamine / dimethylacetamide.

After winding the yarns of Examples 1 to 4 and Comparative Examples and commercial products in a low-temperature atmosphere,
Aged for 60 hours, and at room temperature with 60% humidity. The sample was exposed to an atmosphere of H for 3 days, and the following four physical properties were measured. The measurement results are shown in Table 1. 1. Water Absorbency The 50-denier elastic yarn was immersed in water at room temperature for 30 seconds, and the water absorption (%) was determined from the percentage difference (weight change) between the weight after immersion and the weight before immersion. 2. Fiber strength It was determined from the measured value (g / d), which is the result of measuring the fiber of each example and the like by the method of JIS-1-1070. In addition, when the fiber strength is high, the strength in the axial direction is high, which means that the yarn does not break when spinning with a spinning machine, and that the spinnability is high. 3. Volume specific resistance value The dope used in each example was cast on release paper,
The film was dried in a dryer at 100 ° C. for 2 hours to prepare a film of about 100 μm, which was measured according to JIS-K-6911. The measurement result was regarded as the volume resistivity value of the yarn made from the dope. did. 4. Stretching In the same manner as the volume resistivity, a film of about 100 μm was prepared and measured by JIS K-6301, and the measurement result was regarded as the stretching of the yarn made from the dope.

[0052]

[Table 1]

As can be seen from Table 1, Examples 1 to 4
It can be seen that the water absorption and the volume specific resistance value are remarkably improved as compared with the commercial product, and the fiber strength is hardly inferior to the commercial product. Furthermore, it turns out that elasticity is almost inferior to a commercial item.

[0054]

According to the present invention, as described above, by imparting a network structure to polyurethane fibers, it is possible to greatly improve high water absorption and antistatic function while maintaining elasticity of the fibers, So the inner foundation,
Provided is a polyurethane fiber that can be suitably used for clothing or medical aids worn in contact with the body, such as pantyhose, socks, gloves, supporters, bandages, and sports equipment such as ski wear and golf wear. can do.

Further, since these preferable physical properties are retained by the polyurethane fiber itself, high-quality polyurethane fiber can be economically obtained without requiring complicated post-treatment.

Claims (3)

[Claims] 1. The following polyurethane resins (A) and (B)
And (B) in a weight ratio of (A) / (B) = 0.5 / 9.5 to 7/3, and then spinning the mixture to produce a polyurethane fiber. . (A) A thermoplastic polyurethane resin obtained by reacting an organic diisocyanate with one or more polymer diols selected from the group consisting of polyethylene glycol and poly (oxyethylene-oxyalkylene) glycol. (B) one or more organic diisocyanates selected from the group consisting of diphenylmethane diisocyanate, tolylene diisocyanate and hexamethylene diisocyanate, a chain extender, and one selected from the group consisting of polytetramethylene glycol and polyester glycol A polyurethane resin obtained by dissolving a product produced by reacting the above polymer diol with a polar organic solvent. 2. The method for producing a polyurethane fiber according to claim 1, wherein the thermoplastic polyurethane resin (A) is used.
Is a thermoplastic polyurethane resin obtained by reacting dicyclohexylmethane diisocyanate and / or diphenylmethane diisocyanate as an organic diisocyanate with polyethylene glycol as a polymer diol, and the polyurethane resin (B) is an organic diisocyanate. It is a polyurethane resin formed by dissolving the product obtained by reacting diphenylmethane diisocyanate, a chain extender, and polytetramethylene glycol as a polymer diol in a polar organic solvent of dimethylformaldehyde. A method for producing a polyurethane fiber. 3. The method for producing a polyurethane fiber according to claim 1, wherein the thermoplastic polyurethane resin (A) is obtained by further reacting a chain extender with the organic diisocyanate and the polymer diol. A method for producing a polyurethane fiber.