JP2007303025A - Polyurethane elastic fiber and dyeing auxiliary - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a polyurethane elastic fiber which has good dyeability and solid dyeability, little discolors, even washed with high temperature water, and has stable hue and good color fastness, and to provide a fiber product having a high commercial value. <P>SOLUTION: This polyurethane elastic fiber contains an effective amount of a specific hydrotalcite compound composed of an ion having a specific structure between layers. Thereby, the dyeability and fastness of the polyurethane elastic fiber is largely improved, and a fiber product containing the polyurethane elastic fibers has good hue and an excellent aesthetic property. The particle physical properties of a specific hydrotalcite and its surface treatment can stabilize production on spinning. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a dyeing aid for polyurethane elastic fibers, a polyurethane elastic fiber having good dyeability and excellent color fastness even in washing with high-temperature water, and a fiber product thereof.

  Polyurethane elastic fibers are widely used in textile products such as foundations, underwear, body suits, pantyhose, swimwear and sportswear because of their excellent stretchability and their excellent physical and chemical properties. Polyurethane elastic fibers are rarely used alone, and are often used after being knitted or woven with nylon fibers or other fiber materials. In particular, it is often used in combination with nylon fibers, and the fabric is usually dyed with an acid dye, an acid dye, and a metal-containing dye, which are anionic dyes used as a dye for nylon.

  However, because the products dyed with polyurethane elastic fibers have low fastness, there is a problem that they are easily discolored by washing and washing with water, etc., and the dyes easily fall off when rubbed with other fabrics. There is a problem that the laundry is stained and contaminated. In addition, nylon dyes well with acid dyes, but polyurethane elastic fibers are only thinly dyed.

  In other words, the dyeability and fastness after dyeing of polyurethane elastic fibers are not sufficient. Conventionally, improvement of dyeing conditions, development of dyes, modification of polyurethane polymers, and addition of phosphoric acid ester metal salts to polyurethane have been improved. Various studies have been made, such as quality improvement, but problems relating to the dyeability of polyurethane elastic fibers remain.

Therefore, the present inventor has proposed that the dyeability of polyurethane can be improved by incorporating a hydrotalcite represented by the following formula (4) into the polyurethane based on a completely new idea (see Patent Document 1).
M ²⁺ _1-x M ³⁺ _x (OH) ₂ A ^n- _{x / n} · mH ₂ O (4)
(Wherein at least one divalent metal M ²⁺ is Mg and Zn, M ³⁺ is at least one trivalent metal of Al and Fe, A ^n-is NO ₃ ^-, Cl ^- , Br ⁻ , ClO ₄ ⁻ , HCOO ⁻ and CH ₃ COO ⁻ represents at least one monovalent anion selected from the group consisting of x and m, each representing a number satisfying the following range: 0 < x <0.5, 0 ≦ m <2)

The hydrotalcites represented by the above formula (4) greatly improved the original dyeability of polyurethane. However, it has nevertheless been found that dyeability and fastness with high-temperature water are insufficient. Furthermore, when An ⁿ is a halogen ion such as Cl and Br, if it remains in a large amount in the polyurethane after dyeing, it may adversely affect the heat resistance, light resistance, etc. of the polyurethane. Furthermore, the hydrotalcites of the formula (4) are hardened when dried during production and are not sufficiently finely divided even when pulverized. This causes frequent yarn breakage during the spinning of polyurethane elastic fibers. Production of elastic fibers may be difficult. A polyurethane elastic fiber excellent in dyeability that solves these problems has not yet been found.

JP 2000-119510 A

  The object of the present invention has not yet been solved by the prior art using the above formula (4), (i) further improves the dyeability of the dye, (ii) overseas (particularly in the case of Europe) at 60 ° C. or higher In some cases, washing may be performed using hot water of about 80 ° C, but even in that case, the problem of reducing the drop of the dye from the polyurethane elastic fiber and suppressing the change in the hue of the fabric before and after washing is solved. It is.

  As a result of diligent investigations to solve the problems, the present inventors have promoted the exchange reaction with the dye by including the hydrotalcite having a specific structure in the polyurethane elastic fiber, and the dye is eluted even in high-temperature washing. As a result, the present inventors have found that the binding force with the dye can be enhanced so that the present invention can be prevented.

That is, the present invention provides the following inventions.
1. A polyurethane elastic fiber comprising a polyurethane polymer and a hydrotalcite represented by the following formula (1) in an amount of 0.1 to 20% by mass based on the polyurethane polymer.

M ²⁺ _1-x Al _x (OH) ₂ B ^- _x · mH ₂ O (1)
(Wherein M ²⁺ is at least one divalent metal of Mg and Zn, and B ⁻ is at least one selected from an ion of a carboxylic acid having an aromatic group or an aromatic amine sulfonate ion) And x and m are numbers satisfying the following ranges: 0 <x <0.5, 0 ≦ m <5)

（但し、上記（２）および（３）式中、ｎは１〜３の整数であり、Ｒ₁は水素原子、炭素原子数が１〜５のアルキル基、アセトアミド基、アミノ基、炭素原子数が１〜５のアルキルオキシ基、アルコキシ基、ヒドロキシ基、ヒドロキシアルキレン基、ヒドロキシアルキレンオキシ基およびアセチル基からなる群から選ばれた基であり（但しｎ＝２〜３の場合、Ｒ₁は同一でも異なっていてもよい）、Ｒ₂は−ＣＯＯイオンまたは−（ＣＨ₂）ｌ−ＣＯＯイオンである（但し、ｌは１〜３の整数である）。） 2. 2. The polyurethane elastic fiber as described in 1 above, wherein B ⁻ in the formula (1) is an ion of a carboxylic acid having an aromatic group represented by the following formula (2) or formula (3).

(In the above formulas (2) and (3), n is an integer of 1 to 3, R ₁ is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, an acetamide group, an amino group, or the number of carbon atoms. Is a group selected from the group consisting of 1 to 5 alkyloxy groups, alkoxy groups, hydroxy groups, hydroxyalkylene groups, hydroxyalkyleneoxy groups and acetyl groups (provided that when n = 2 to 3, R ₁ is the same) R ₂ is —COO ion or — (CH ₂ ) 1 —COO ion (where 1 is an integer of 1 to 3).

3. 3. The polyurethane elastic fiber as described in 2 above, wherein B ⁻ in the formula (1) is a benzoate ion.
4). 3. The polyurethane elastic fiber according to 2 above, wherein B ⁻ in the formula (1) is a p-aminobenzoate ion.

5). 2. The polyurethane elastic fiber as described in 1 above, wherein B ⁻ in formula (1) is a metanylate ion.
6). The polyurethane elastic fiber according to any one of 1 to 5 above, wherein the range of x in the formula (1) is 0.2 ≦ x ≦ 0.4.

7). The polyurethane elastic fiber according to any one of 1 to 6 above, wherein an interlayer distance d ₀₀₃ of hydrotalcite is 13Å ≦ d ₀₀₃ ≦ 25Å as measured by an X-ray diffraction method.
8). The polyurethane elastic fiber according to any one of 1 to 7 above, wherein the hydrotalcite has an average secondary particle diameter of 2 μm or less and a BET specific surface area of 5 to ²⁰ m ² / g.

  9. Hydrotalcite is an anionic surfactant selected from the group of 0.1 to 10% by mass of higher fatty acid based on hydrotalcite, alkali metal salt of higher fatty acid and phosphate ester, or silane, titanate and The polyurethane elastic fiber according to any one of 1 to 8 above, wherein the polyurethane elastic fiber is surface-treated with at least one coupling agent selected from an aluminum group.

  10. The polymer diol component constituting the polyurethane polymer is a single polymer having a number average molecular weight of 500 to 6000, in which one or two or more linear or branched alkylene groups having 2 to 10 carbon atoms are ether-bonded. The polyurethane elastic fiber according to any one of 1 to 9 above, which is a monopolymerized or copolymerized polyalkylene ether diol.

11. A fiber product comprising the polyurethane elastic fiber according to any one of 1 to 10 above and a fiber material selected from the group consisting of nylon, ester, acrylic, natural fiber, and cellulose derivative.
12 Item 12. The textile product according to Item 11, which is used for an application selected from the group consisting of an inner, an outer, a leg, a sports wear, jeans, a swimsuit, and a sanitary material.

13. A dyeing assistant for polyurethane elastic fibers comprising hydrotalcites represented by the following formula (1).
M ²⁺ _1-x Al _x (OH) ₂ B ^- _x · mH ₂ O (1)
(Wherein M ²⁺ is at least one divalent metal of Mg and Zn, and B ⁻ is at least one selected from an ion of a carboxylic acid having an aromatic group or an aromatic amine sulfonate ion) And x and m are numbers satisfying the following ranges: 0 <x <0.5, 0 ≦ m <5)

（但し、上記（２）および（３）式中、ｎは１〜３の整数であり、Ｒ₁は水素原子、炭素原子数が１〜５のアルキル基、アセトアミド基、アミノ基、炭素原子数が１〜５のアルキルオキシ基、アルコキシ基、ヒドロキシ基、ヒドロキシアルキレン基、ヒドロキシアルキレンオキシ基およびアセチル基からなる群から選ばれた基であり（但しｎ＝２〜３の場合、Ｒ₁は同一でも異なっていてもよい）、Ｒ₂は−ＣＯＯイオンまたは−（ＣＨ₂）ｌ−ＣＯＯイオンである（但し、ｌは１〜３の整数である）。） 14 14. The dyeing aid for polyurethane elastic fibers as described in 13 above, wherein B ⁻ in the formula (1) is an ion of a carboxylic acid having an aromatic group represented by the following formula (2) or formula (3).

(In the above formulas (2) and (3), n is an integer of 1 to 3, R ₁ is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, an acetamide group, an amino group, or the number of carbon atoms. Is a group selected from the group consisting of 1 to 5 alkyloxy groups, alkoxy groups, hydroxy groups, hydroxyalkylene groups, hydroxyalkyleneoxy groups and acetyl groups (provided that when n = 2 to 3, R ₁ is the same) R ₂ is —COO ion or — (CH ₂ ) 1 —COO ion (where 1 is an integer of 1 to 3).

15. 15. The dyeing aid for polyurethane elastic fibers according to the above 14, wherein B ⁻ in the formula (1) is a benzoate ion.
16. 15. The dyeing aid for polyurethane elastic fibers according to the above 14, wherein B ⁻ in the formula (1) is p-aminobenzoate ion.
17. 14. The dyeing assistant for polyurethane elastic fibers according to the above 13, wherein B ⁻ in the formula (1) is methanyl ion.

The polyurethane elastic fiber containing the hydrotalcite having a specific structure of the present invention and the fiber product thereof are excellent in the same color and color developability, and have good aesthetics as a product. Furthermore, the hue fastness at the time of high temperature washing is also excellent. In addition, the heat resistance and light resistance of the polyurethane elastic fiber are not adversely affected. Further, when producing polyurethane elastic fibers, there are few interruptions in the spinning process, which is superior in stable productivity.
In addition, when a copolymer diol is used as a raw material for polyurethane, the dyeability is improved more than when a polytetramethylene diol, which is a single diol, is used.

  As a result of intensive studies to solve the above-mentioned problems of hydrotalcites, the present inventor has found that the anion in the structure is an anion having a structure in which a carbonyl group is bonded to an aromatic group exhibiting appropriate lipophilicity. Or an aromatic amine sulfonate ion.

That is, the reduction robustness during insufficient and hot water washing of dyeability cause the acid dye in the dye bath, the hydrotalcites represented by conventional Formula (4) anion A ^n- and of The ion exchange rate was not high. As a result of intensive studies on the conditions of hydrotalcites necessary for increasing the ion exchange rate, it was found that the following three conditions should be satisfied. As a first condition, it is preferable that the ionic radius of the anion is as large as possible. As a result, the layer interval occupied by B ⁻ in the hydrotalcite crystal structure can be increased, so that the acid dye molecule can easily approach the anion and be exchanged. Space to react is secured. As a second condition, it is necessary that an acidic dye having an aromatic group as a chromophore has an affinity for an anion. As a third condition, it is preferable that the binding force between the anion ionically present between the hydrotalcite layers and the hydrotalcite base layer (upper and lower metal hydroxide layers) is not too strong. In other words, it is necessary for the ion exchange reaction that the ionic bond strength of the anion to the basic layer is moderately weaker than that of the acid dye.

As a result of further studies, it has been found that polyurethane elastic fibers containing hydrotalcites described in the following formula (1) can satisfy the above conditions.
M ²⁺ _1-x Al _x (OH) ₂ B ^- _x · mH ₂ O (1)
In the formula (1), M ²⁺ is at least one divalent metal of Mg and Zn, and B ⁻ is at least selected from a carboxylic acid ion having an aromatic group or an aromatic amine sulfonate ion. X and m are numbers satisfying the following ranges. 0 <x <0.5, 0 ≦ m <5. A preferable range of x is 0.2 ≦ x ≦ 0.4.

上記（２）および（３）式中、ｎは１〜３の整数であり、Ｒ₁は水素原子、炭素原子数が１〜５のアルキル基、アセトアミド基、アミノ基、炭素原子数が１〜５のアルキルオキシ基、アルコキシ基、ヒドロキシ基、ヒドロキシアルキレン基、ヒドロキシアルキレンオキシ基およびアセチル基からなる群から選ばれた基であり（但しｎ＝２〜３の場合、Ｒ₁は同一でも異なっていてもよい）、Ｒ₂は、―ＣＯＯイオンまたは−（ＣＨ₂）ｌ−ＣＯＯイオンである（但し、ｌは１〜３の整数である）。
なお、上記式（１）のＢ^-において、さらに不純物としてのＣＯ₃ ^2-が含有されていてもよい。含有量は、好ましくは２％以下、特に好ましくは１％以下である。ＣＯ₃ ^2-を少量含有しても、本発明の効果を有する。ＣＯ₃ ^2-以外の不純物アニオンについても、同様である。 One feature of the present invention is that B ^{− in the} formula (1) is an ion of a carboxylic acid having an aromatic group. Specifically, B ⁻ is preferably a carboxylic acid ion having an aromatic group represented by the following formula (2) or formula (3).

In the formulas (2) and (3), n is an integer of 1 to 3, and R ₁ is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, an acetamide group, an amino group, or a carbon atom number of 1 to 1. 5 is a group selected from the group consisting of an alkyloxy group, an alkoxy group, a hydroxy group, a hydroxyalkylene group, a hydroxyalkyleneoxy group and an acetyl group (provided that when n = 2 to 3, R ₁ is the same or different. R ₂ is —COO ion or — (CH ₂ ) 1 —COO ion (where l is an integer of 1 to 3).
Incidentally, B in the formula (1) ^- In, may be further CO ₃ ^2- is contained as an impurity. The content is preferably 2% or less, particularly preferably 1% or less. Even if it contains a small amount of CO ₃ ^2- , it has the effect of the present invention. The same applies to impurity anions other than CO ₃ ^2- .

Hereinafter, the effect expression mechanism of the hydrotalcites will be described.
Satisfaction of the first condition is that the ion exchange reaction is accelerated. That is, the distance between the (003) planes of hydrotalcites is preferably 13Å ≦ d ₀₀₃ ≦ 25Å, and if it is greater than 13Å, the dye molecule can easily approach the B ⁻ ion that undergoes an exchange reaction, so Easy to go. However, when it exceeds 25 kg, the synthesis yield of the hydrotalcite itself of formula (1) may be low. More preferably 14Å ≦ d ₀₀₃ ≦ 20Å. More preferably 15Å ≦ d ₀₀₃ ≦ 18Å.

The surface spacing d of the (003) plane of Cl type, NO ₃ type and acetic acid type hydrotalcites is about 7.7 mm, 8.9 mm and 12.8 mm, respectively, but the dyeability is not sufficient. In the case of a benzoate anion which is one of the preferred examples of the present invention, d ₀₀₃ = 15.8Å is clearly large, and the dyeability and fastness are good. Furthermore, if the anion has an aromatic group, the acid dye generally has an aromatic group as its chromophore group and has a basic skeleton similar to that of the anion of the present invention, so that the chemical structure is hydrotalcite. Dyes substituted with anions between layers tend to exist sterically and stably in hydrotalcite. Therefore, even during high-temperature washing, there is little detachment of the dye from the fiber and the fastness is good.

The second condition will be described in detail. The lauric acid type and stearic acid type in which the anion has an aliphatic group and a carboxylic acid group have d ₀₀₃ of 12 Å or more and have lipophilicity. In addition, since the ion exchange rate by the acid dye is small, a sufficient dyeing effect cannot be obtained. However, surprisingly, it has been found that an anion having an aromatic group exhibiting moderate lipophilicity has a particularly superior effect than an aliphatic carboxylic acid type anion exhibiting strong lipophilicity. That, B of formula (1) ^- was found to be the anion is required to have at least one or more aromatic groups.

Wherein, referring to the third condition specifically, even though an anion having an aromatic group, a dodecyl benzene sulfonic acid type, despite d ₀₀₃ is sufficiently large as about 15～16A, sulfone group The chemical bonding force is too strong for the basic layer of hydrotalcite crystal. However, in the case of the aromatic aminosulfonic acid type in which the aromatic hydrogen is substituted with an amino group, the bond between the sulfonic acid group and the basic layer is weakened due to the repulsion between the positive charge of the amino group and the basic layer, Therefore, it is easy to exchange ions with the dye. It was found that it is preferable that the bonding group with the base layer is a carboxyl group and the anion which is not as strong as the sulfone group is a benzoic acid ion type because ion exchange with an acidic dye occurs more rapidly.

To hydrotalcite of the above formula (1) does not adversely affect the heat resistance and light resistance of the polyurethane, B ^- it is necessary that itself does not adversely affect the polyurethane. For this purpose, it is not preferred that B ⁻ is a halogen-containing ion. If it is an ion of an aromatic carboxylic acid or an aromatic amine sulfonate ion, the ion exchange property is good, the dyeability is high, and there is almost no acid remaining in the dyed polyurethane. The amount is small and therefore the impact on polyurethane is negligible.

  Inhibition of yarn breakage during spinning of polyurethane elastic fibers by the hydrotalcites of the above formula (1) is oleophilic (acid type is difficult to water) if it is an anion of an aromatic carboxylic acid or an aromatic amine sulfonate ion. Because it has water-repellent properties because part of the crystal surface of hydrotalcite is chemically adsorbed by acid, it also has a water-repellent property when it is dried. This achieves the prevention of caking between hydrotalcites and the formation of fine particles during pulverization. That is, even after drying, it is in a soft state, and therefore, it is easily made into fine particles by normal pulverization to the original level. The hydrotalcites of the above formula (4) may not sufficiently prevent solidification because of the close proximity of primary particles during drying.

  As described above, the hydrotalcite having an anion of a carboxylic acid having an aromatic group or an aromatic amine sulfonate ion of the present invention overcomes all the weak points of the hydrotalcite of formula (4) of the prior art. it can.

Of the present invention, B having an aromatic group and a carboxylic acid group ^- Specific examples of the anion, benzoic acid ion, 4-propyl benzoate, p- tertiary butyl benzoate, p- hydroxybenzoic acid ions, 4-hydroxy-3-methoxybenzoate ion, p-acetamidobenzoate ion, 4-methoxybenzoate ion, p-aminobenzoate ion, 2-amino-4-methylbenzoate ion, β-naphthoate ion, 4- Examples thereof include amino salicylate ions, anisoleate ions, p-hydroxyphenylacetate ions, m-aminobenzenesulfonate ions (methanilate ions) and p-aminobenzenesulfonate ions.

  However, the aromatic group has an OH group directly, for example, p-hydroxybenzoic acid ion, 4-hydroxy-3-methoxybenzoic acid ion, etc., because the OH group has a chemical bonding force to the basic layer. The ion exchange capacity with the dye may decrease. Therefore, it is more preferable not to have an OH group in addition to the carboxylic acid group because ion exchange with the dye is effective. Particularly preferred is benzoate ion.

  In the present invention, the hydrotalcite is contained in a polyurethane polymer in an amount of 0.1 to 20% by weight. If it is this range, an effect can be expressed, without exerting a bad influence on a fiber. Preferably it is 1 to 6% by weight.

In the case of using polyurethane elastic fibers as a dyeing assistant, the necessary conditions to be provided are not only excellent dyeability as described above, but also the spinnability in the production of polyurethane elastic fibers is extremely important. Can't spin. In order to satisfy this requirement, not only the type of anion but also the physical properties of the hydrotalcite crystal itself are extremely important. The maximum secondary particle diameter of the hydrotalcites is preferably 5 μm or less, more preferably 3 μm or less. Moreover, it is preferable if an average secondary particle diameter is 2 micrometers or less, More preferably, it is 1 micrometer or less. And a BET specific surface area is preferably as long as 1-30 m ² / g, more preferably in the range of 5 to 20 m ² / g.

  Furthermore, the hydrotalcites of the present invention, in order to further improve the spinnability of the polyurethane elastic fiber, in addition to the above properties, an anionic surfactant such as a higher fatty acid or an alkali metal salt thereof, a phosphate ester, etc. It can be used after being surface-treated with at least one surface treatment agent such as a coupling agent (silane-based, titanate-based, aluminum-based), preferably an anionic surfactant. The amount of the surface treatment agent used here is preferably from 0.1 to 10% by weight, more preferably from 0.5 to 5% by weight, based on the hydrotalcite.

The hydrotalcite used in the present invention is ion-exchanged with the hydrotalcite of the above formula (4) with an anion B ^{− further} selected from a carboxylate ion having an aromatic group or an aromatic amine sulfonate ion. By doing so, it can be suitably obtained. For example, the following method can be used.

As the first step, a mixed aqueous solution of Mg and / or Zn and Al chloride, nitrate, sulfate and other water-soluble salts and alkali, for example, alkali metal hydroxide or sodium carbonate such as sodium hydroxide, potassium hydroxide, An aqueous solution of an alkali metal carbonate such as potassium carbonate is coprecipitated with stirring at a pH of 6 or more, preferably 9 or more, and the resulting precipitate is washed with the aforementioned alkali metal carbonate aqueous solution, washed with water, and CO ₃ type. Manufacture hydrotalcites. In the second step, after the CO ₃ type hydrotalcite is dispersed in water, hydrothermal treatment is performed by autoclaving at 100 to 250 ° C., preferably 120 to 200 ° C. for 1 hour or more, preferably 10 hours or more. As a third step, at least one of nitric acid, hydrochloric acid and perchloric acid is reacted with CO ₃ type hydrotalcite at an equivalent amount or more with respect to CO ₃ to convert CO ₃ to NO ₃ , Cl or ClO ₄ , respectively. . As a fourth step, the above monovalent anion is added with an alkali metal salt aqueous solution of a compound having an aromatic group such as sodium benzoate and having a carboxylic acid group, and an ion exchange reaction is carried out by adding 1.6 equivalents or more. Thereafter, conventional treatments such as filtration, washing, drying, pulverization and classification can be appropriately selected and used to produce the dyeing aid of the present invention.

As another production method, in the first step, the use of an alkali metal carbonate as an alkali is omitted, and a monovalent inorganic anion of Cl type, Br type, NO ₃ type and ClO ₄ type is synthesized, After the hydrothermal treatment, the third step can be omitted and the fourth step can be performed. Furthermore, when performing surface treatment, it can carry out after completion | finish of a 2nd or 3rd or 4th process.

  The polyurethane elastic fiber of the present invention can be obtained by spinning a polyurethane polymer containing the hydrotalcite of the above formula (1). The polyurethane polymer is obtained by a known method in which an active hydrogen-containing compound is reacted with a prepolymer obtained by reacting a polymer diol and diisocyanate.

  Examples of the polymer diol used in the polyurethane polymer used in the present invention include polyester diol, polycarbonate diol, and polyether diol. Polyether diols are preferred, and more specifically, polyalkylene ether diols in which one or two or more linear or branched alkylene groups having 2 to 10 carbon atoms are ether-bonded.

  The polyalkylene ether diol is a single or copolymer polyalkylene having a number average molecular weight of 500 to 6000, in which one or two or more linear or branched alkylene groups having 2 to 10 carbon atoms are ether-bonded. Ether diol. The copolymerized polyalkylene ether diol is a copolymerized polyalkylene ether diol having a number average molecular weight of 500 to 6000, in which an alkylene group is ether-bonded in a block shape or a random shape. Compared to PTMG (polytetramethylene ether glycol), a single-polymerized polyalkylene ether diol widely used as a raw material for polyurethane elastic fibers, a copolymer polyalkylene ether diol composed of two or more types of alkylene groups. In the case of a polyurethane elastic fiber using a polyurethane, since the diol component occupying 65 wt% to 85 wt% of the polyurethane component is amorphous, the dye easily penetrates into the polymer, and the hydrotalcite of the present invention Since the exchange reaction with the dye proceeds efficiently, a vivid color with a better hue can be obtained.

  In addition, the advantage of using a copolymerized diol is that the elastic function is further improved, so that this polyurethane elastic fiber has excellent elastic function, namely high elongation at break, small stress fluctuation with respect to strain at elongation and Has low hysteresis loss of stress etc. Therefore, pantyhose and outerwear using the same have an excellent elastic function, are excellent in wearing feeling, and have good aesthetic properties. Among the copolymerized polyalkylene ether diols, a copolymerized polyalkylene ether diol containing a butylene group, that is, a tetramethylene ether unit, is preferable from the viewpoint of water resistance, light resistance, abrasion resistance, elastic function, and the like of the obtained polyurethane elastic fiber. Furthermore, a combination of a butylene group, that is, a tetramethylene ether unit and a 2,2-dimethylpropylene group, that is, a neopentylene ether unit, or a combination of a tetramethylene ether unit and a 2-methylbutylene group is preferable.

  The alkylene ether unit other than the tetramethylene group is preferably contained in an amount of 4 mol% to 85 mol%. If the alkylene ether unit is less than 4 mol%, the effect of improving the elastic function of spandex is small, and if it exceeds 85 mol%, the strength or elongation of the elastic fiber is greatly reduced. The number average molecular weight (Mn) of the polyalkylene ether diol used in the present invention is 500 to 6000, preferably 1000 to 4000. When Mn is smaller than 500, the elastic recoverability is lowered, and when it is larger than 6000, the spinnability is deteriorated.

  Examples of the diisocyanate used in the polyurethane of the present invention include known aliphatic, alicyclic or aromatic organic diisocyanates having two isocyanate groups in the molecule. Specifically, 4,4'-diphenylmethane diisocyanate, 2,4- or 2,6-tolylene diisocyanate, p-phenylene diisocyanate, 1,5-naphthalene diisocyanate, xylylene diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, 4 An organic diisocyanate such as 4,4'-dicyclohexylmethane diisocyanate is exemplified, and 4,4'-diphenylmethane diisocyanate is preferable. Moreover, you may use the compound which has the blocked isocyanate group converted into a free isocyanate group as organic diisocyanate.

  As the active hydrogen-containing compound that reacts with the isocyanate group used in the polyurethane of the present invention, a conventional chain extender in polyurethane, that is, a low molecular compound having a molecular weight of 500 or less containing at least two hydrogen atoms that can react with isocyanate. Can be used. Specific examples thereof include diamines such as ethylenediamine, propylenediamine, tolylenediamine, m-xylylenediamine, 1,3-diaminocyclohexane, isophoronediamine, hydrazine, 4,4'-diaminodiphenylmethane, dihydrazide, piperazine, and the like. Examples thereof include diamine compounds disclosed in JP-A No. 5-155842, diols such as ethylene glycol, propylene glycol, and 1,4-butanediol, preferably ethylenediamine, 1,2-propylenediamine, and JP-A Examples thereof include diamine compounds disclosed in JP-A-5-155581. These compounds may be used alone or in admixture of two or more. Moreover, you may use together with the compound containing one active hydrogen which can react with isocyanate depending on the case.

  As a method for producing polyurethane using diisocyanate, polymer diol, and active hydrogen-containing compound, a known urethanization technique can be employed. The stoichiometric ratio of various compounds used in the present invention is such that the sum of the hydroxyl groups of the polymer diol and the active hydrogens of the active hydrogen-containing compound is 1.00 or more and 1.07 equivalents relative to the isocyanate group of the diisocyanate compound. Less than is preferable.

The specific viscosity (ηsp / c) of the polyurethane polymer constituting the polyurethane elastic fiber of the present invention is preferably 1.1 to 3.5 dl / g. By setting it as this range, it becomes an elastic fiber excellent in elastic recovery property. Here, the specific viscosity (ηsp / c) is a value calculated by (η / η ₀ −1) / C in an N, N′-dimethylacetamide solvent. (Where C is the solution viscosity (0.5 wt%) of polymer 0.5 g / DMAC 99.5 g, η is the number of seconds dropped in the dilute solution by Ostwald viscometer, and η ₀ is the same as for DMAC by viscometer. Is the number of seconds of falling.)

  The polyurethane polymer thus obtained is further added to known organic or inorganic compound heat stabilizers, antioxidants, UV inhibitors, yellowing inhibitors, heat discoloration inhibitors and anti-resistance agents useful for polyurethane polymers. A sterilizing chlorine agent for pools may be added.

  The polyurethane polymer composition thus obtained can be formed into a fiber by any of the conventionally known dry spinning method, wet spinning method and melt spinning method. A polyurethane elastic fiber obtained by dry spinning is preferable from the viewpoint of heat resistance and durability.

In the case of dry spinning, the hydrotalcite of the present invention is a B ⁻ ion comprising an organic substance since the polyurethane polymer composition containing the hydrotalcite of the present invention is exposed to a high temperature for a short time, usually within 1 second. Is relatively stable and easily exerts its effect. In the case of melt spinning, since it is kept in a high temperature state for a long time, in some cases, B ^- ions may partially change and the dyeing effect may not be sufficient. This is particularly effective in the case of polyurethane elastic fibers that are dry-spun using a solvent.

  At this time, a known oil agent for polyurethane elastic fibers may be further adhered as an oil agent from the outside using an oiling device during spinning. The oil component used here is, in addition to ether-modified silicone, polyester-modified silicone, polyether-modified silicone, polyamino-modified silicone, polyorganosiloxane, mineral oil, talc, silica, colloidal alumina and other mineral fine particles, magnesium stearate Also, various fatty acid metal salt powders such as calcium stearate, higher aliphatic carboxylic acids, higher aliphatic alcohols, waxes that are solid at room temperature such as paraffin polyethylene, and the like may be used in combination.

  The polyurethane elastic fiber obtained in this way may be used as a bare thread as it is in practice, and other fibers such as polyamide fiber, wool, cotton, regenerated fiber, polyester fiber and the like are conventionally known. It can also be used as a coated elastic fiber by coating with a fiber. In particular, it is preferably used in combination with a fiber material selected from the group consisting of nylon, ester, acrylic, natural fiber and cellulose derivative.

  The polyurethane elastic fiber of the present invention is suitable for use in tights and pantyhose, but is not limited to this, foundations, socks, mouth rubber, corsets, surgical bandages, woven and knitted swimsuits, etc. Can also be used. In particular, it is preferably used for applications selected from the group consisting of inner, outer, legs, sports wear, jeans, swimwear and sanitary materials.

  When the polyurethane elastic fiber of the present invention is dyed, the same method as the dyeing method of ordinary synthetic fiber and natural fiber may be used. That is, dyeing methods such as a dip dyeing method, a pad steam method, a pad thermofix method, a textile printing method, and a spray method can be applied. As the dyeing machine, a normal dyeing machine such as a liquid dyeing machine, a Wins dyeing machine, and an airflow dyeing machine can be used.

  EXAMPLES Hereinafter, the present invention will be described in detail with reference to examples, but the present invention is not limited to these examples.

Various evaluations were performed by the following methods.
(1) Measurement of interplanar distance of (003) plane of hydrotalcites The powder was calculated using the 2θ strongest peak measured by wide-angle X-ray diffraction method.
(Reference, Phy Chem Minerals, 14.377. (1987))
(2) Measurement of average secondary particle size and maximum secondary particle size The powder was put in ethanol and treated with ultrasound for 5 minutes, and then the particle size distribution in the ethanol solvent was measured by laser diffraction method.

(3) Measurement of BET value It measured by the nitrogen adsorption method.
(4) Evaluation of spinning stability A spinning stock solution containing various additives produced according to the method described in the following examples was spun for about 10 hours by the method described in the examples, and the number of yarn breaks (times / Time). The smaller the number of times, the more stable the productivity.

(5) Dyeability evaluation of polyurethane elastic fiber A two-weight recot knitted fabric was used for dyeing evaluation. That is, a 33 dt / 10f nylon fiber is used for the front heel, a 44 dt polyurethane elastic fiber of this example or comparative example is used for the middle heel and the back heel, the front heel structure is 10/23, and the middle heel structure is 10/01. Then, a two-weight ricott knitted fabric having a back heel structure of 12/10 was knitted. The blending ratio of polyurethane elastic fibers in this fabric was 35%, and was put into a continuous scouring machine in the expanded state. At this time, use a continuous scouring machine with four liquid tanks, change the temperature at which the fabrics pass sequentially, such as 20 ° C, 50 ° C, 70 ° C, 90 ° C, and in each liquid tank 2 g / L of a scouring agent (score roll FC-250 manufactured by Kao Corporation) was added. The cloth which passed through the continuous scouring machine was dehydrated with a mangle after passing through a washing bath, and pre-set at 190 ° C. for 45 seconds with a pin tenter.

  Next, the mixture was put into a liquid flow dyeing machine, and 2g / L of a scouring agent (score roll FC-250 manufactured by Kao Co., Ltd.) was added in the solution for scouring, followed by scouring in an acidic bath at 70 ° C for 20 minutes. After draining, rinsing and re-watering, a black acidic dye adjusted to pH 4 was added and dyed at 95 ° C. for 60 minutes.

  After rinsing, fix processing (natural tannin S 6% owf, tartar L L 3% owf 80 ° C / 40 minutes treatment), the fabric is removed from the dyeing machine, processed with a soft resin, and further at 170 ° C with a pin tenter. Finishing set was performed.

The criteria for determining the level of dyeability when dyed black were as follows.
Grade 5 dark black,
4th grade black,
3rd class light black,
2nd grade gray,
Grade 1 light gray

(6) Dye fastness to fabric Evaluation was made by JIS L0844 discoloration.
In this case, the detergent used was Kao Co., Ltd. detergent product name “ATTACK” 2 g / L, washing for 30 minutes each under two conditions of 50 ° C. and 80 ° C., rinsed with running water for 30 minutes, dehydrated, and room temperature The change in hue after drying for 24 hours was measured at 20 ° C. and 65% RH.
Hue change (Class Δ) = class before washing the fabric-class after washing the fabric The higher the series before washing and the smaller the Δ class value, the less the color change and the better the dyeability and fastness. It can be said that there is.

Example 1
[Synthesis of dyeing assistant hydrotalcite (B ⁻ : benzoate anion)]
After filtering and washing the NO ₃ -type hydrotalcite synthesized according to [Example 1-A] of JP-A-2000-119510, the surface treatment is not performed and the water is again dried to about 4 liters without drying. The mixture was uniformly dispersed with a stirrer and heated to about 70 ° C. To this, about 2 liters of an aqueous solution (about 70 ° C.) in which 3.92 mol of sodium benzoate was dissolved was added with stirring and reacted for about 30 minutes. Then, it is filtered, washed with about 2 liters of warm water (about 60 ° C.), heated to about 40 ° C., and with stirring, about 100 g of an aqueous solution (about 40 ° C.) in which 2 g of sodium stearate is dissolved is added. Added and surface treated. Thereafter, it was filtered, washed with water, dried at 120 ° C. for 10 hours, and pulverized with an atomizer. The X-ray diffraction of this product was shifted to d ₀₀₃ = 15.8 mm, and the NO ₃ -type diffraction was completely lost. The composition obtained by chemical analysis and thermal analysis is as follows.
Mg _0.68 Al _0.32 (OH) ₂ (C ₆ H ₅ COO) _0.32 · 0.54H ₂ O
The BET specific surface area measured by the liquid nitrogen adsorption method was 14 m ² / g, treated with ultrasonic waves in an isopropyl alcohol solvent for 5 minutes, and the particle size distribution measured by the laser diffraction method was the average secondary particle size = 0.42 μm, The maximum secondary particle size was 0.92 μm.

[Polymerization polymerization and production of polyurethane elastic fiber]
400 g of polytetramethylene ether diol having a number average molecular weight of 1800, which is a single polymerization diol, and 91.7 g of 4,4′-diphenylmethane diisocyanate are reacted under stirring in a dry nitrogen atmosphere at 80 ° C. for 3 hours, A polyurethane prepolymer capped with an isocyanate was obtained. After cooling to room temperature, 720 g of dimethylacetamide was added and dissolved to prepare a polyurethane prepolymer solution. On the other hand, 8.111 g of ethylenediamine and 1.37 g of diethylamine were dissolved in 390 g of dimethylacetamide and added to the prepolymer solution at room temperature to obtain a polyurethane solution having a viscosity of 4000 poise (30 ° C.).

  Next, 1% by mass of 4,4′-butylidenebis- (3-methyl-6-tert-butylphenol) and 0.5% by mass of 2- (2′-hydroxy-3′-) with respect to the polyurethane solid content. (t-Ptyl-5′-methylphenyl) -5-chloro-benzotriazole and 3% by mass of the above hydrotalcite were added to 130 g of a dimethylacetamide solvent, and the solution uniformly dissolved and uniformly dispersed by high-speed stirring was used. In addition to the obtained polyurethane solution, the mixture was stirred to obtain a uniform stock solution for spinning.

The stock solution for spinning thus obtained was defoamed and then extruded into hot air from the pores of 16 spinnerets (each of which has 4 pores) to evaporate the solvent. The dried yarn is falsely twisted in the process of passing through a ring false twister, and an oil mainly composed of dimethyl silicon is applied to the oiling roller via a Godet roller and wound around a paper tube at a speed of 600 m / min. The polyurethane elastic fiber of 44 dt / 4 filament was obtained.
Various evaluation results of the obtained polyurethane elastic fiber are shown in Table 1.

(Examples 2 and 3)
In the synthesis of the dyeing assistant, a dyeing assistant was synthesized in the same manner as in Example 1 except that sodium p-aminobenzoate and sodium sodium naphthoate were used instead of sodium benzoate. Using the obtained dyeing assistant, polyurethane elastic fibers were spun in the same manner as in Example 1 and evaluated. Various evaluation results of the obtained polyurethane elastic fiber are shown in Table 1.

(Comparative Example 1)
Polyurethane elastic fibers were spun and evaluated in the same manner as in Example 1 except that the dyeing assistant hydrotalcite was not added. Various evaluation results of the obtained polyurethane elastic fiber are shown in Table 1.

(Comparative Example 2)
A polyurethane elastic fiber was spun and evaluated in the same manner as in Example 1 except that the NO ₃ type hydrotalcite synthesized in Example 1 was used as it was as a dyeing assistant. Various evaluation results of the obtained polyurethane elastic fiber are shown in Table 1.

Example 4
[Polymerization polymerization and production of polyurethane elastic fiber]
In the same manner as in Example 1, except that a copolymerized diol, a copolymerized poly (tetramethylene / neopentylene) ether diol (neopentylene copolymerization rate 11 mol%), which is a copolymerized diol, was used as the diol raw material. A polyurethane solution was obtained. The viscosity of the obtained polyurethane solution was 3200 poise (30 ° C.).

  A polyurethane elastic fiber was spun and evaluated in the same manner as in Example 1 except that this polyurethane solution was used. Various evaluation results of the obtained polyurethane elastic fiber are shown in Table 2.

(Example 5)
In the synthesis of the dyeing assistant, a dyeing assistant was synthesized in the same manner as in Example 1 except that sodium m-aminobenzenesulfonate (sodium metanylate) was used instead of sodium benzoate. Using the obtained dyeing assistant, polyurethane elastic fibers were spun in the same manner as in Example 4 and evaluated. Various evaluation results of the obtained polyurethane elastic fiber are shown in Table 2.

(Comparative Example 3)
Polyurethane elastic fibers were spun and evaluated in the same manner as in Example 4 except that the dyeing aid hydrotalcite was not added. Various evaluation results of the obtained polyurethane elastic fiber are shown in Table 1.

(Comparative Example 4)
As a dyeing assistant, the commercially available hydrotalcite (trade name DHT-4) used in the synthesis of NO ₃ type hydrotalcite in Example 1 (BET = 12 m ² / g, average secondary particle size 0.76 μm). A polyurethane elastic fiber in the same manner as in Example 4 except that a maximum secondary particle size of 1.81 μm and a chemical composition of Mg _0.67 Al _0.33 (OH) ₂ (CO ₃ ) _0.165 · 0.50H ₂ O) were used. Spinning and evaluation were carried out. Various evaluation results of the obtained polyurethane elastic fiber are shown in Table 2.

(Comparative Example 5)
A polyurethane elastic fiber was spun and evaluated in the same manner as in Example 4 except that the NO ₃ type hydrotalcite synthesized in Example 1 was used as it was as a dyeing assistant. Various evaluation results of the obtained polyurethane elastic fiber are shown in Table 2.

  The polyurethane elastic fiber of the present invention can be used as a coated elastic fiber by coating with bare yarn or other fibers (polyamide fiber, wool, cotton, recycled fiber, polyester fiber, etc.). Although it is particularly suitable for use in tights and pantyhose, the present invention is not limited thereto, and can also be used for foundations, socks, mouth rubber, corsets, surgical bandages, and woven or knitted swimsuits.

Claims (17)

A polyurethane elastic fiber comprising a polyurethane polymer and a hydrotalcite represented by the following formula (1) in an amount of 0.1 to 20% by mass based on the polyurethane polymer.
M ²⁺ _1-x Al _x (OH) ₂ B ^- _x · mH ₂ O (1)
(Wherein M ²⁺ is at least one divalent metal of Mg and Zn, and B ⁻ is at least one selected from an ion of a carboxylic acid having an aromatic group or an aromatic amine sulfonate ion) And x and m are numbers satisfying the following ranges: 0 <x <0.5, 0 ≦ m <5) B in the formula (1) ^- polyurethane elastic fiber according to claim 1 which is an ion of a carboxylic acid having an aromatic group represented by the following formula (2) or formula (3).

(In the above formulas (2) and (3), n is an integer of 1 to 3, R ₁ is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, an acetamide group, an amino group, or the number of carbon atoms. Is a group selected from the group consisting of 1 to 5 alkyloxy groups, alkoxy groups, hydroxy groups, hydroxyalkylene groups, hydroxyalkyleneoxy groups and acetyl groups (provided that when n = 2 to 3, R ₁ is the same) R ₂ is —COO ion or — (CH ₂ ) 1 —COO ion (where 1 is an integer of 1 to 3). The polyurethane elastic fiber according to claim 2 is a benzoate ion ^- B in the formula (1). B in the formula (1) ^- polyurethane elastic fiber according to claim 2 is p- aminobenzoic acid ion. The polyurethane elastic fiber according to claim 1 is metanilic acid ion ^- B in the formula (1).   The range of x in Formula (1) is 0.2 <= x <= 0.4, The polyurethane elastic fiber as described in any one of Claims 1-5. Interlayer distance d ₀₀₃ of the hydrotalcites, polyurethane elastic fiber according to any one of claims 1 to 6 is 13Å ≦ d ₀₀₃ ≦ 25Å in measurements at X-ray diffraction method. The polyurethane elastic fiber according to any one of claims 1 to 7, wherein the hydrotalcite has an average secondary particle diameter of 2 µm or less and a BET specific surface area of 5 to ²⁰ m ² / g.   Hydrotalcite is an anionic surfactant selected from the group of 0.1 to 10% by mass of higher fatty acid based on hydrotalcite, alkali metal salt of higher fatty acid and phosphate ester, or silane, titanate and The polyurethane elastic fiber according to any one of claims 1 to 8, wherein the polyurethane elastic fiber is surface-treated with at least one coupling agent selected from an aluminum group.   The polymer diol component constituting the polyurethane polymer is a single polymer having a number average molecular weight of 500 to 6000, in which one or two or more linear or branched alkylene groups having 2 to 10 carbon atoms are ether-bonded. The polyurethane elastic fiber according to claim 1, which is a monopolymerized or copolymerized polyalkylene ether diol.   A fiber product comprising the polyurethane elastic fiber according to any one of claims 1 to 10 and a fiber material selected from the group consisting of nylon, ester, acrylic, natural fiber, and cellulose derivative.   The textile product according to claim 11, which is used for an application selected from the group consisting of an inner, an outer, a leg, a sportsway, jeans, a swimsuit and a sanitary material. A dyeing assistant for polyurethane elastic fibers comprising hydrotalcites represented by the following formula (1).
M ²⁺ _1-x Al _x (OH) ₂ B ^- _x · mH ₂ O (1)
(Wherein M ²⁺ is at least one divalent metal of Mg and Zn, and B ⁻ is at least one selected from an ion of a carboxylic acid having an aromatic group or an aromatic amine sulfonate ion) And x and m are numbers satisfying the following ranges: 0 <x <0.5, 0 ≦ m <5) Polyurethane elastic fibers for dyeing assistant according to claim 13 which is an ion of a carboxylic acid having an aromatic group represented by the following formula (2) or formula (3) ^- B in the formula (1).

(In the above formulas (2) and (3), n is an integer of 1 to 3, R ₁ is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, an acetamide group, an amino group, or the number of carbon atoms. Is a group selected from the group consisting of 1 to 5 alkyloxy groups, alkoxy groups, hydroxy groups, hydroxyalkylene groups, hydroxyalkyleneoxy groups and acetyl groups (provided that when n = 2 to 3, R ₁ is the same) R ₂ is —COO ion or — (CH ₂ ) 1 —COO ion (where 1 is an integer of 1 to 3). B in the formula (1) ^- polyurethane elastic fibers for dyeing assistant according to claim 14 which is a benzoic acid ion. Polyurethane elastic fibers for dyeing assistant according to claim 14 is the p- aminobenzoic acid ion ^- B in the formula (1). B in the formula (1) ^- polyurethane elastic fibers for dyeing assistant according to claim 13 which is metanilic acid ion.