JP2001073274A - Polyamide fiber structure and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To produce a polyamide fiber structure that has high moisture absorp tion and soft fabric hand and shows excellent yellowing resistance, while it retains the merits of polyamide fibers, for example, high mechanical strength, resistance to chemicals, dyecolor development, and the like, and a production process therefor. SOLUTION: This polyamide fiber structure includes a polyamide filament having a moisture-absorbing and releasing parameter (ΔMR) of >=2.5% as a constitution filament and has a polyamide fiber structure having the moisture- absorbing and releasing parameter (ΔMR) of >=2.5% and a yellowing degree (ΔYI) of <=5 by vanillin. Further, this polyamide fiber structure is produced by treating a polyamide filament structure that includes a polyamide filament having the moisture-absorbing and releasing parameter (ΔMR) of >=2.5% as a constitution filament and is obtained by treating a polyamide fiber structure having the moisture-absorbing and releasing parameter (ΔMR) of >=2.5% with an aqueous medium including an acid anhydride.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polyamide fiber structure having hygroscopicity and excellent yellowing resistance.

[0002]

2. Description of the Related Art Polyamide fibers have excellent properties such as mechanical strength, chemical resistance, heat resistance, coloring properties, washing durability, and soft touch, and are mainly used for clothing, socks, and industrial applications. Widely used for. However, on the other hand, although the moisture absorbency of polyamide fiber is higher than that of polyester fiber, it is extremely low compared to natural fibers such as cotton, so it directly touches the skin like sportswear, swimwear, underwear, socks, or Applications that are worn close to the skin have the drawback of causing stuffiness and stickiness due to perspiration from the skin.

[0003] For these reasons, polyamide fibers are
In terms of comfort, it is inferior to natural fibers represented by cotton and cellulosic synthetic fibers represented by rayon,
This was a major problem to be improved when used for applications that touch the skin.

[0004]

SUMMARY OF THE INVENTION In order to solve the above-mentioned drawbacks of polyamide fibers, it has been attempted to obtain fibers having high equilibrium moisture content (moisture absorption) by blending, twisting, or aligning them to obtain moisture-absorbing comfort. There is an attempt to do. However, according to this measure, although comfort is improved for the time being, the effect is not necessarily sufficient, and contamination is caused by acid dyes generally used when dyeing synthetic fibers, or the same color is obtained. Inferiorly, there is a problem in that the original physical properties of the synthetic fiber are lost.

There is also a method of imparting hygroscopicity in a post-processing stage. However, in order to obtain sufficient hygroscopicity by this method, it is necessary to cause a large amount of hygroscopic resin to be picked up by the fibrous structure, and it is necessary to make the thickness of the fibrous structure to a certain size, It cannot be applied to the field using thin fabric. Further, even if sufficient hygroscopicity is obtained, there is a drawback that the texture of the fiber is hardened due to the formation of a film of the hygroscopic resin on the fiber surface, and the feel is poor when worn. In addition, because resin falls due to washing,
There is also the problem of poor durability.

Further, polyamide fibers have a drawback that they turn yellow due to nitric oxide compounds in the atmosphere, vanillin which is a decomposition product of glycine contained in cardboard, BHT contained in packaging materials and the like. It is said that the amino group at the terminal of the molecular structure of the fiber is involved.

[0007] Polyamide fibers have a drawback of yellowing, and therefore have a problem to be solved, such as a hue change due to yellowing when developed in white or light color.

As means for solving the drawbacks of the polyamide fibers, various proposals have conventionally been made as a method for imparting yellowing resistance to polyamide fiber structures.
For example, a method of reducing the amount of amino groups by mixing an acid anhydride at the time of spinning is disclosed in Japanese Patent Application Laid-Open No. 1-229810, but the spinning property becomes poor or the dyeing property decreases. There was a problem.

Further, as disclosed in JP-A-55-47150, a method of treating a polyamide fiber with an anionic compound comprising a sulfonic acid group or a sulfate ester group to ionically block an amino group. However, depending on the treatment method, there is a problem that the yellowing resistance is not always sufficient and the durability is lacking.

The present invention has been made in view of the above-mentioned problems of the prior art, and has been made in consideration of the properties of polyamide fibers such as mechanical strength, chemical resistance, and the like.
An object of the present invention is to provide a polyamide fiber structure having high hygroscopicity and a soft feel while maintaining color development and the like, and having excellent yellowing resistance and a method for producing the same.

[0011]

The present invention adopts the following means to solve the above-mentioned problems.
That is, the polyamide fiber structure of the present invention contains a polyamide-based filament having a moisture absorption / desorption parameter (ΔMR) of 2.5% or more as a constituent yarn, and has a moisture absorption / desorption parameter (ΔMR) of 2.5%. % Or more, and the yellowing degree (ΔYI) due to vanillin is 5 or less.

Further, the method for producing a polyamide fiber structure of the present invention has a moisture absorption / desorption parameter (ΔMR) of 2.5.
% Of a polyamide-based filament structure containing polyamide filaments of at least 2.5% as constituent yarns and having a moisture absorption / release parameter (ΔMR) of at least 2.5% with an aqueous medium containing an acid anhydride. It is a feature.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention has high moisture absorption and a soft touch while maintaining the above-mentioned objects, that is, mechanical strength, chemical resistance, color development, etc., which are characteristics of polyamide fibers, and The polyamide fiber structure excellent in yellowing resistance was closely examined, and the moisture absorption / desorption parameter (ΔMR) was 2.
Surprisingly, when the garment is composed of a fiber structure containing 5% or more of polyamide-based filaments and the fiber structure itself has a moisture absorption / desorption parameter (ΔMR) of 2.5% or more, the polyamide fiber It has been clarified that it has a high moisture absorption and a soft feel while having the original mechanical strength, chemical resistance and coloring properties, so that a comfortable wearing feeling can be guaranteed. Further, it has been clarified that when the yellowing degree (ΔYI) is 5 or less, the yellowing resistance is excellent and the problem of yellowing at the distribution stage or the like can be solved.

The polyamide fiber structure of the present invention contains a highly hygroscopic polyamide filament having a moisture absorption / desorption parameter (ΔMR) of 2.5% or more in its constituent yarn. Such a fiber structure does not necessarily need to be composed solely of a highly hygroscopic polyamide-based filament, and may be mixed with other fibers as long as the intrinsic mechanical strength, chemical resistance, dyeing properties, etc. of the polyamide fiber are not impaired. They may be woven, mixed, or knitted.

As described above, the highly hygroscopic polyamide filament used in the present invention has a moisture absorption / desorption parameter (パ ラ メ ー タ ー
MR) is 2.5% or more, and
It is necessary that the fiber structure composed of the polyamide filament also has a moisture absorption / desorption parameter (ΔMR) of 2.5% or more. More preferably, the moisture absorption / desorption parameter (ΔMR) of the highly hygroscopic polyamide-based filament and the fiber structure is 3 to 8%, and still more preferably 4 to 8%.
And the comfort when worn as clothes can be further improved.

The moisture absorption / desorption parameter (ΔMR) of the polyamide filament yarn and the polyamide fiber structure is 2.
If it is less than 5%, it is difficult to prevent stuffiness and stickiness due to perspiration from the skin due to low moisture absorption, and the object of the present invention cannot be achieved. On the other hand, when the moisture absorption / desorption parameter (ΔMR) is larger than 8%, the stickiness due to the absorbed moisture increases.

In the present invention, the “moisture absorption / desorption parameter (△
MR) ”means the moisture absorption MR at 30 ° C. × 90% RH.
2 and the difference in moisture absorption MR1 at 20 ° C. × 65% RH, and is a value represented by the following equation.

The moisture absorption / desorption parameter (ΔMR) (%) = MR2-MR1 That is, the moisture absorption / desorption parameter (ΔMR) is used to obtain comfort by releasing moisture in clothes when the clothes are worn to the outside air. And the moisture absorption rate at the humidity in clothes represented by 30 ° C. × 90% RH and the outer moisture represented by 20 ° C. × 65% RH when performing light to moderate exercise. It represents the difference from the moisture absorption at the time of temperature and humidity. In the present invention, this moisture absorption / desorption parameter (ΔMR) is used as a scale for evaluating moisture absorption. The larger the value, the higher the moisture absorption / desorption power, and the better the comfort when worn.

The degree of yellowing of the polyamide fiber structure of the present invention
(ΔYI) is preferably 5 or less, more preferably 3 or less. If the yellowing degree (△ YI) exceeds 5,
The yellowing is severe, and the hue change due to the yellowing can be visually confirmed.

In order to accurately indicate the "degree of yellowing (△ YI)" in the present invention, the yellowing resistance of the polyamide-based fiber structure of the present invention is measured using a multi-source spectrophotometer described later. Refers to a value.

Specifically, the polyamide fiber structure of the present invention was immersed in a 0.5% by weight vanillin / ethanol solution, air-dried, and then subjected to a heat treatment at 150 ° C. for 4 minutes. The difference between the measured value and the measured value before immersion in a 0.5% by weight vanillin / ethanol solution is shown.
The smaller the value, the better the yellowing resistance.

In the present invention, there is no particular limitation on the technology necessary for expressing the function with respect to the moisture absorption / desorption parameters (ΔMR) and the degree of yellowing (ΔYI) which characterize the polyamide fiber structure. .

The polyamide filament used in the present invention is not particularly limited as long as it contains a polyamide component and has a moisture absorption / desorption parameter (ΔMR) of 2.5% or more. Considering the yarn-making properties, knitting properties, knitting properties, dyeing properties and the durability of the yarn performance, it is preferable to use fibers having the following constitution.

That is, the polyamide filament used in the present invention has a pyrrolidone content of 0.10% by weight.
Those containing 3 to 15% by weight of the following polyvinylpyrrolidone are preferred. This particular polyvinylpyrrolidone (hereinafter referred to as PVP) is characterized in that the amount of pyrrolidone contained therein is extremely low, at 0.10% by weight or less. This PVP is a moisture-absorbing component, and is preferably contained in an amount of 3% by weight or more and 15% by weight or less with respect to the polyamide in order to suppress stuffiness and stickiness when worn as clothes. Particularly preferably 4
-8% by weight. When the content of such PVP is less than 3% by weight, the hygroscopicity becomes insufficient, and the clothes targeted by the present invention cannot be obtained. Also, 15
If the amount is too large, the stickiness will be increased, the comfort during wearing will be inferior, and it will be difficult to stably produce yarn.

The content of pyrrolidone in the PVP is preferably 0.10% by weight or less, more preferably 0.05% by weight or less, and particularly preferably 0.03% by weight.
It is as follows. When the content of this pyrrolidone is too large, the color tone in the state of the greige after weaving takes on a yellow tint, so that the color tone after dyeing has a dull feeling, and the desired color tone and luxury feeling can be obtained. Can not be done.

Polyamide filaments include nylon 6, nylon 66, nylon 610, nylon 46,
Any polyamide long fiber made of a copolymer of these polyamides may be used, and is not particularly limited. Also, the cross-sectional shape of these polyamide filaments is
The cross section may be any of a round section, a three-lobe section, a four-lobe section, and a hollow section, and is not particularly limited.

Further, pigments such as titanium oxide and carbon black, various antioxidants, coloring inhibitors, light stabilizers, antistatic agents and the like are added to such polyamide filaments within a range not to impair the object of the present invention. May be.

The degree of yellowing (ΔYI) is not limited as long as the degree of yellowing (ΔYI) of the polyamide fiber structure is 5 or less, and the means is not limited. Various functional processes such as a charging process, an antifouling process, and a light-resistant process may be provided as long as the object of the present invention is not impaired.

In terms of processing, the polyamide fiber structure having a moisture absorption / desorption parameter (ΔMR) of preferably 2.5% or more is treated with an aqueous medium containing an acid anhydride. As such a processing form, in any state of a thread such as a hull or cheese, or a state of a fabric such as a woven or knitted material, treatment with an aqueous medium containing an acid anhydride is possible, and is not particularly limited.

The acid anhydride as referred to in the present invention refers to a product obtained by dehydration-condensation of two acids and a product obtained by dehydration-condensation of a divalent or higher acid in a molecule. Specific examples thereof include acetic anhydride, maleic anhydride, and anhydride. Succinic acid, valeric anhydride, glutaric anhydride, benzoic anhydride, phthalic anhydride, hexanoic anhydride, naphthalic anhydride, trifluoroacetic anhydride, etc. can be used, but from the point of high versatility and safety, It is preferable to use acetic anhydride or maleic anhydride.

The term "aqueous medium" as used herein means a medium containing 50% or more of water. The content of the acid anhydride using such a medium is not particularly limited, but generally, the content of the acid anhydride is preferably 0.1% by weight or more based on 1 g of the fiber.

The treatment methods include a bath immersion method, a padding method,
Known methods such as a coating method, a spraying method, and a printing method can be employed, and may be performed before, during, or after dyeing. The treatment temperature is not particularly limited, but is preferably 60 ° C. or higher from the viewpoint of increasing the reaction rate. The treatment time is not particularly limited, but it is preferable to perform treatment for at least 1 minute after adding the acid anhydride from the viewpoint of effectively obtaining the treatment effect.

The polyamide-based fiber structure obtained by such a method has an effect of having yellowing resistance excellent in uniformity and hardly affecting the dyeability.

The polyamide fiber structure of the present invention may be used for clothing, or may be partially used for a part of clothing, without any limitation.

[0035]

The present invention will be described below in more detail with reference to examples. In Examples, evaluation of characteristics and the like is as follows.
It was determined by the following method. [Hygroscopic parameter (放 MR)] Yarn or knitted fabric 1
3g, weight at the time of drying, each 20 ℃ × 65%
The moisture absorption of the following equation was calculated from the weight change after standing for 24 hours in a commercial thermo-hygrostat at RH and 30 ° C. × 90% RH.

Moisture absorption rate (%) = [(weight after moisture absorption-weight when dried) / weight when absolutely dry] × 100 The moisture absorption rate MR1 under the above-mentioned conditions of 20 ° C. × 65% RH and 30 ° C. × 90. From the moisture absorption rate MR2 under the condition of% RH,
The required difference in moisture absorption rate (ΔMR:%) = MR2-MR1 is taken as the moisture absorption / desorption parameter. [Pyrrolidone content] 1 to 3 g of the yarn is dissolved in chloroform, and gas chromatogram analysis is performed by a standard method using a GC14A type device manufactured by Shimadzu Corporation. The pyrrolidone content is determined by the following equation.

Pyrrolidone content = [(GC peak area /
Calibration curve coefficient) (mg / ml) x solution amount (ml) / sample amount (mg)] x 100 [Measurement of yellowing degree (△ YI)] The yellowing degree YI value of the cloth is measured using the above-mentioned multi-source spectrophotometer (YI1). 2. The cloth was immersed in a 0.5% by weight vanillin / ethanol solution, excess liquid was removed between filter papers, air-dried, and then heat-treated at 150 ° C. for 4 minutes. 3. The yellowing degree YI value after the heat treatment is measured in the same manner as described above (YI2). 4. The value of (YI2)-(YI1) was defined as the degree of yellowing (ΔYI). The smaller the value of the degree of yellowing (ΔYI), the better the yellowing resistance. The yellowing degree YI value was measured using a multi-light source spectrophotometer (manufactured by Suga Test Instruments Co., Ltd.) using a C light source and a visual field of 2 °.
Was measured. Example 1 As PVP, using isopropyl alcohol as a solvent,
PVP having a pyrrolidone content of 0.02% by weight synthesized by an ordinary method was obtained. This PVP was kneaded with nylon 6 using an extruder to obtain a master polymer chip having a PVP concentration of 30% by weight.

This master polymer chip and ordinary nylon 6 chip were blended at a predetermined ratio, and the content of PVP with respect to nylon 6 in the blend chip was set to 3% by weight.

This blended chip was prepared by a conventional nylon melt spinning method using 3% by weight of PVP and 0.02% of pyrrolidone.
A nylon 6 filament of 30 denier 10 filaments (single yarn fineness of 3.0 denier) containing 10% by weight was obtained.

The nylon 6 filament raw yarn had a moisture absorption / desorption parameter (ΔMR) of 3.9%. Aiming at knitting for running shirts and pants, this filament 100
After knitting the greige fabric with the half structure of the tricot knitting machine 36G, the finished density is 51 wells / inch, 73 courses / inch, and the basis weight is 86 g / m ² , according to the ordinary nylon tricot fabric dyeing method. A knit was produced.

1 g of this knit was placed in 100 g of hot water at 90 ° C., and 0.1 g of acetic anhydride was added, followed by treatment for 5 minutes.
After washing and drying, the fabric had a yellowing degree (ΔYI) of 2.5, excellent yellowing resistance, and a moisture absorption / release parameter (ΔMR) of 3.9%. Comparative Example 1 Nylon 6 knitted fabric used in Example 1 (basis weight 86 g / m ² )
The same procedure as in Example 1 was performed except that 1 g of acetic anhydride was not added. The yellowing degree of the fabric after washing with water and drying (△
YI) was 22 and yellowing resistance was insufficient, and the moisture absorption / desorption parameter (ΔMR) was 3.9%. Example 2 140 denier 24 containing 7% by weight of PVP and 0.08% by weight of pyrrolidone by the same melt spinning method as in Example 1.
Nylon 6 in filament (5.8 denier)
Filament was obtained.

The moisture absorption / desorption parameter (ΔMR) of the nylon 6 filament raw yarn was 6.1%. Aiming at a knitted fabric for baseball uniform, using this filament 100%, a knitting machine is knitted with a mock rody structure of a double circular knitting machine 22G, and then, according to a normal nylon circular knitted fabric dyeing method, a finishing density of 44 wells / inch. And a knitted fabric having a basis weight of 265 g / m ² at 51 courses / inch.

1 g of the knit was placed in 100 g of hot water at 90 ° C., and 0.1 g of acetic anhydride was added, followed by treatment for 5 minutes.
After washing and drying, the fabric has a yellowing degree (ΔYI) of 2.7, which is excellent in yellowing resistance, and a moisture absorption / desorption parameter (ΔMR) of 6.
1%. Comparative Example 2 Nylon 6 knitted fabric used in Example 2 (basis weight 265 g / m ² )
1 g was treated in the same manner as in Example 2 except that acetic anhydride was not added. Yellowness of the fabric after washing and drying
(ΔYI) was 25 and yellowing resistance was insufficient, and the moisture absorption / release parameter (ΔMR) was 6.1%. Example 3 By the same melt spinning method as in Example 1, 15% by weight of PVP,
160 denier 4 containing 0.03% by weight of pyrrolidone
A nylon 6 filament of 8 filaments (single yarn fineness: 3.3 denier) was obtained.

The moisture absorption / desorption parameter (ΔMR) of the nylon 6 filament raw yarn was 7.1%. Aiming at a knitted fabric for training wear, with a double circular knitting machine 22G, a reversible structure in which 50% of this filament is arranged on the front side and 50% of ordinary nylon 6 filament is arranged on the back side,
After knitting the greige machine, the finishing density is 42 wells / inch, 53 course /
A knitted fabric having a basis weight of 320 g / m ² was produced.

1 g of this knit was placed in 100 g of hot water at 90 ° C., and 0.1 g of acetic anhydride was added, followed by treatment for 5 minutes.
After washing and drying, the fabric has a yellowing degree (ΔYI) of 3.0, which is excellent in yellowing resistance, and a moisture absorption / desorption parameter (ΔMR) of 3.
6%. Comparative Example 3 The nylon 6 knitted fabric used in Example 3 (basis weight 320 g /
m ² ) 1 g was treated in the same manner as in Example 2 except that acetic anhydride was not added. After washing with water and drying, the fabric had a yellowing degree (ΔYI) of 24, which was insufficient in yellowing resistance, and a moisture absorption / release parameter (ΔMR) of 3.6%. Comparative Example 4 Normal 30 denier 10 filament (single yarn fineness: 3.0 denier) nylon 6 filaments containing no PVP and pyrrolidone were used.

The nylon 6 filament raw yarn had a moisture absorption / desorption parameter (ΔMR) of 2.0%. A knitted fabric for a running shirt / pants is aimed at in the same manner as in Example 1. Using this filament 100%, a greige fabric is knitted in a half structure of a tricot knitting machine 36G, and then finished in accordance with a usual nylon tricot fabric dyeing method. Density 52 wells /
A knitted fabric having a basis weight of 84 g / m ² was produced at an inch of 71 courses / inch.

1 g of this knit was placed in 100 g of hot water at 90 ° C., and 0.1 g of acetic anhydride was added, followed by treatment for 5 minutes.
After washing with water and drying, the fabric had a yellowing degree (ΔYI) of 2.6 and was excellent in yellowing resistance, but had a moisture absorption / release parameter (ΔMR) of 2.0%. Comparative Example 5 Nylon 6 knitted fabric used in Comparative Example 4 (basis weight: 84 g / m ² )
1 g was treated in the same manner as in Example 1 except that acetic anhydride was not added. Yellowness of the fabric after washing and drying
(ΔYI) was 24, indicating that the yellowing resistance was insufficient, and the moisture absorption / release parameter (ΔMR) was 2.0%.

[0048]

[Table 1]

As is clear from Table 1, the filaments containing PVP in Nylon 6 of Examples 1 to 3 and the knitted fabrics made of the filaments have a better moisture absorption / desorption parameter than those of Comparative Examples 1 to 5. It can be seen that a fiber structure having a performance of (ΔMR) of 2.5% or more and a yellowing degree (ΔYI) of 5 or less can be obtained by performing the treatment with acetic anhydride. That is, by having both of these properties, it is possible to obtain a polyamide fiber structure having high hygroscopicity and a soft feel and having excellent yellowing resistance.

[0050]

According to the present invention, it is possible to provide a garment having a comfortable wearing feeling because it has a high moisture absorption and a soft feel while having the inherent mechanical strength, chemical resistance, and coloring properties of polyamide fiber. Can be.

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 4L031 AA20 AB01 CA15 DA00 DA08 4L035 BB31 EE05 LC01 LC02 LC04 LC08

Claims (4)

[Claims] 1. A moisture absorption / desorption parameter (ΔMR) of 2.5%
A polyamide fiber structure containing the above polyamide filament as a constituent yarn, and having a moisture absorption / release parameter (ΔMR) of 2.5% or more, and having a yellowing degree (ΔYI) due to vanillin. A polyamide fiber structure having a particle size of 5 or less. 2. The polyamide fiber structure according to claim 1, wherein the polyamide filament comprises a highly hygroscopic polyamide containing 3 to 15% by weight of polyvinylpyrrolidone having a pyrrolidone content of 0.10% by weight or less. 3. A moisture absorption / desorption parameter (ΔMR) of 2.5%
A polyamide fiber structure containing the polyamide-based filament as a constituent yarn and having a moisture absorption / desorption parameter (ΔMR) of 2.5% or more is treated with an aqueous medium containing an acid anhydride. A method for producing a polyamide fiber structure. 4. The polyamide fiber structure according to claim 3, wherein the polyamide fiber structure is treated with the aqueous medium until the degree of vanillin yellowing (ΔYI) becomes 5 or less. Production method.