JPH0987978A - Dyeing processing of fiber structure containing spun yarn of para amide fiber - Google Patents

Abstract

PROBLEM TO BE SOLVED: To perform a dyeing processing excellent in dyeability, quality and color fastness by treating para aramid fibers in a polar solvent in a pretreatment, spinning them into a spun yarn and subsequently dyeing it. SOLUTION: Short fibers of para aramid fiber are immersed into a polar solvent such as dimethyl sulfoxide, treated at >=70 deg.C for >=5min and then, spun by an ordinary method to obtain a spun yarn. A woven fabric is produced using the obtained spun yarn. Subsequently, the woven fabric is dyed using a disperse dye or a cationic dye at a temperature of >=130 deg.C and <=200 deg.C.

Description

Detailed Description of the Invention

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for dyeing a fiber structure containing para-aramid fiber in at least a part thereof.

[0002]

2. Description of the Related Art Aramid fibers, especially para-aramid fibers, have high specific strength, specific elastic modulus, excellent heat resistance, chemical resistance, etc., so that ropes, nets, fishing nets or protective work clothes for industrial materials are used. However, since it has high crystallinity, strong intermolecular bonding force and a dense molecular structure, it is difficult to color it by a conventional dyeing technique, and the following methods have been proposed.

For example, JP-A-63-256765 or JP-A-2-41414 discloses a method for obtaining a colored yarn by dispersing a dye or a pigment in a spinning solution of concentrated sulfuric acid to prepare a yarn. JP-A-3-76868 discloses a method of obtaining polyparaphenylene terephthalamide (PPTA) fiber dyeable with a cationic dye by pre-immersing it in a sulfuric acid solution and then contacting it with a dyeing accelerator. It is not always sufficient in terms of the range of hue to be obtained, the reproducibility of dyeing, the light fastness and the physical properties.

In order to develop the use of the dyed para-aramid fiber to the characteristics of the para-aramid fiber, the width of the product is limited when the fabric is made of aramid fiber alone. It is often the case that products are proposed by mixing with general-purpose fibers such as fibers. However, there is still no effective means for dyeing both polyester fibers and para-aramid fibers. JP-A-5-209
Japanese Laid-Open Patent Publication No. 372 proposes a method of dyeing para-aramid fibers at a high temperature of 160 ° C. or higher using a disperse dye. It is not preferable to dye at high temperature.

Further, when dimethylsulfoxide treatment is carried out after the para-aramid fiber and other fiber are mixed to form a cloth, there are the following problems. Para aramid fiber /
In the case of polyester fiber mixed woven fabric, if dimethyl sulfoxide treatment is performed after forming the woven fabric, the polyester fiber is also subjected to swelling treatment, and dimethyl sulfoxide other than para-aramid fiber does not need to be dimethyl sulfoxide treated. There is a problem that not only the amount of dimethylsulfoxide used increases and the chemical cost increases due to the adhesion of sulfoxide, but also the cost of waste liquid treatment increases in terms of pollution. Also, if appropriate dyes and dyeing conditions are selected, both can be dyed in the same color, but there is a large difference in shrinkage due to the swelling treatment between the para-aramid fiber and the polyester fiber, and the shrinkage of the fabric itself is noticeable. There is a problem that it does not finish well.

There is a heat-resistant cloth composed of para-aramid fiber and meta-aramid fiber (for example, Japanese Patent Application No. 1-22).
No. 1537), there is no technique for dyeing both the same color, and when para-aramid fiber and meta-aramid fiber mixed fabric is woven and treated with dimethyl sulfoxide, the para-aramid fiber and meta-aramid fiber are treated. Both fibers can be dyed in almost the same color. However, the meta-aramid fiber is significantly contracted by dimethylsulfoxide, and there are many problems in physical properties and quality such as reduction in strength and adhesion of oligomers, and it is currently difficult to put it into practical use.

[0007]

DISCLOSURE OF THE INVENTION An object of the present invention is to allow a fiber structure composed of para-aramid fibers and other fibers to be dyed and processed with various hues with good dyeing fastness, and para-aramid fibers. It is an object of the present invention to provide a method for dyeing and processing a fiber structure containing a para-aramid fiber spun yarn that can be dyed without shrinkage of the cloth due to shrinkage of the fabric.

[0008]

According to the present invention, when dyeing a fiber structure containing a para-aramid fiber spun yarn, the para-aramid fiber is treated with a polar solvent before spinning and then made into a spun yarn, A method for dyeing and processing a fiber structure containing a para-aramid fiber spun yarn, which is characterized by dyeing. In order to achieve the object of the present invention, para-aramid fiber is previously treated with dimethyl sulfoxide, which is a polar solvent, at a temperature of 70 ° C. or higher for 5 minutes or more, and then spun, or polyester fiber or meta-aramid fiber. It is preferable to blend with, and then dye at 130 ° C. or higher.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION The para-aramid fiber in the present invention means a PPTA fiber typified by Kevlar manufactured by DuPont or a copolymer with 3,4'-oxydiphenylene terephthalamide (manufactured by Teijin Ltd., Trademark; Technora), etc., and refers to an aromatic polyamide fiber having a paraphenylene group incorporated in the main chain.

The first step of the dyeing method of the present invention is to treat the para-aramid fiber with a polar solvent. This treatment is performed in the state before spinning the para-aramid fiber, that is, in the state where the fiber is tow or soft cotton. By treating para-aramid fiber with a polar solvent, the fiber swells, the dense molecular structure in the fiber is loosened, and the dye becomes a structure that can diffuse into the inside of the fiber. Penetrates easily. Further, when the dyeing is completed, the original dense structure is restored, so that the dye is fixed inside the fiber and the washing fastness is also improved.

Examples of the polar solvent used in the present invention include dimethylsulfoxide, dimethylformamide, dimethylacetamide, N-methylpyrrolidone and sulfolane. Among them, dimethylsulfoxide is particularly preferable in terms of improvement in dyeability. preferable. However, when dimethyl sulfoxide is used, the shrinkage due to the treatment is large,
Since fibers may be entangled, dimethyl sulfoxide and water or another polar solvent may be mixed and used. The proportion of water or other polar solvent mixed with dimethyl sulfoxide is preferably less than 50% by weight, particularly preferably 15 to 35%.

The temperature at which the para-aramid fiber structure is treated with the polar solvent is preferably 70 ° C. or higher, and particularly preferably 80 ° C. to 140 ° C. Processing temperature is 7
If the temperature is lower than 0 ° C, the dye cannot be sufficiently diffused inside the fiber during dyeing. The treatment time at this time is preferably 5 minutes or more, and particularly preferably 15 to 60 minutes. If it is less than 5 minutes, the effect may be insufficient or the treatment may be uneven. After the treatment with the polar solvent, it is desirable to carry out washing with hot water, washing with water or heat treatment in order to remove the contained solvent. Further, these treatments may be performed after forming the fiber structure in the second step described later.

Next, as the second step of the dyeing method of the present invention, the para-aramid fiber treated with the polar solvent is spun, and if necessary, woven, knitted, twisted (hereinafter Are collectively referred to as "secondary processing"),
Form a para-aramid fiber structure. The fiber structure referred to here is, for example, a fiber structure such as a woven fabric, a knitted fabric, a spun yarn, or a rope.

When forming the para-aramid fiber structure, other fibers may be used in combination in order to enable development to various uses. Examples of the other fiber used together with the para-aramid fiber include synthetic fiber such as polyester fiber and meta-aramid fiber, natural fiber or regenerated fiber, and among them, polyester fiber and meta-aramid fiber are preferable. Hereinafter, the other fiber used together with the para-aramid fiber may be simply referred to as "other fiber".

The term "polyester fiber" as used herein means terephthalic acid as a main dicarboxylic acid component and at least one glycol, preferably at least one alkylene glycol selected from ethylene glycol, trimethylene glycol and the like as a main glycol component. Such as polyester.

The meta-aramid fiber is a fiber made of polymetaphenyleneisophthalamide fiber or a copolymer containing it as a main component (for example, manufactured by Teijin Ltd., trademark: Conex). Other fibers may contain stabilizers, antioxidants, flame retardants, antistatic agents, optical brighteners, catalysts, anti-coloring agents, heat-resistant agents, colorants, inorganic particles, etc., if necessary. it can.

When the para-aramid fiber and other fiber are used in combination, they may be mixed-spun, or they may be spun separately and then subjected to secondary processing, and the combination method may be appropriately selected. You can choose.

In the para-aramid fiber construction as described above,
The para-aramid fiber is at least 1% by weight or more, preferably 3% by weight or more, more preferably 5 to 30% by weight.
It is. The ratio of para-aramid fiber in the fiber structure is 1
If it is less than weight%, the effect of the present invention is not sufficiently exhibited.

As the third step of the dyeing method of the present invention,
The fiber structure is dyed. Dyes used for dyeing are disperse dyes and cationic dyes. The disperse dye is a dye which is sparingly soluble in water and is used for dyeing hydrophobic fibers from a system dispersed in water, and is often used for dyeing polyester fibers, acetate fibers and the like. The disperse dye can be appropriately selected, and examples thereof include benzeneazo type (monoazo, disazo, etc.), heterocyclic azo type (thiazoleazoazo, benzothiazoleazo, quinolineazo, pyrizoneazo, imidazoleazo,
Thiophene azo etc.), anthraquinone type, condensed type (quinophthalene, styryl, coumarin etc.) and the like.

The cationic dye is a water-soluble dye that is soluble in water and has a basic group, and is often used for dyeing acrylic fibers, natural fibers, cationic dyeable polyester fibers, and the like. . The cationic dye can be appropriately selected, for example, diacrylmethane-based and triacrylmethane-based, quinoneimine (azine, oxazine, thiazine) -based, xanthene-based,
Examples thereof include methine type (polymethine, azamethine), heterocyclic azo type (thiazole azo, triazole azo, benzothiazole azo), and anthraquinone type. Further, recently, there is a cationic dye which is dispersed by blocking a basic group, but both can be used.

The dyeing temperature is preferably 130 to 200 ° C., more preferably 140 to 170 ° C. If the dyeing temperature is lower than 130 ° C, there is a possibility that dyeing cannot be sufficiently performed. Further, the higher the dyeing temperature, the higher the dyeability, but if it exceeds 200 ° C., problems such as dye decomposition and polyester fiber deterioration may start to occur.

[0022]

EXAMPLES Next, the present invention will be described in detail with reference to examples. Hereinafter, unless otherwise specified, the ratio and% are based on weight. Example 1 3,4'-oxydiphenylene terephthalamide and PP
Para-aramid fiber (Teijin Co., Ltd., trademark; Technora) short fiber (1.5 de,
51mm cut, crimp number = 10 / in, strength = 28g
/ De).

The short fibers were immersed and stirred in dimethyl sulfoxide heated to 80 ° C. and treated for 30 minutes. Then, it was washed with hot water at 100 ° C. for 30 minutes, thoroughly washed with water, and then dried. Then, short fibers (1.
25 de × 38 mm) and mixed at a ratio of 10/90,
It was spun by a conventional method. Using this spun yarn, a fabric of para-aramid fiber / polyester fiber mixed fabric was formed. Then, the cloth is scorerolled 400 (manufactured by Kao Corporation) 1
Scouring was carried out at 80 ° C. for 20 minutes at g / l. The refined cloth,
After washing with water and drying, dyeing was carried out at 160 ° C. for 60 minutes in a dyeing bath having the composition shown in Table 1 while increasing the temperature from room temperature at a rate of 2 ° C./min. At this time, the ratio of the cloth to the dyebath is 1:30.
And After that, in a cleaning bath having the composition shown in Table 1 at 80 ° C
Then, reduction cleaning was performed for 20 minutes. Then, the final set was performed at 160 ° C. for 1 minute.

The dyed fabric obtained as described above was evaluated for dyeability, quality and dyeing fastness by the following methods, and a fabric excellent in dyeability and quality was obtained. Further, this cloth also had good dyeing fastness. The bathochromativity (K / S) was used as a scale showing the dyeing effect. This value is given by the Kubelka-Munk (Kubel) equation (I) below, where R is the reflectance of the sample at a specific wavelength.
ka-Munk). The larger this value, the greater the dyeing effect. K / S = (1-R) ² /2R...(I) The measurement is Macbeth COL (Macbeth COL).
OR-EYE model M-2020PL).

The quality and quality of the cloth were evaluated by sensory judgment by five skilled persons regarding the appearance and texture of the cloth, and were expressed in three grades of ◯ (good), Δ (somewhat bad), and × (bad). Dyeing fastness The dyeing fastness was evaluated by the A-2 method shown in JIS L 0844-73. Table 3 shows the results.

[0026]

[Table 1]

* 1; manufactured by Bayer Co., Ltd. * 2; manufactured by Meisei Chemical Co., Ltd. * 3; nonionic activator, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.

Comparative Example 1 A fabric was prepared by blending short fibers of polyester fibers together with short fibers of polyester fibers in the same manner as in Example 1 except that the same short fibers of para-aramid fibers as in Example 1 were used and were not treated with dimethyl sulfoxide. Formed, scoured, washed with water, dried and dyed. When this plain woven fabric was evaluated for dyeability, quality and dyeing fastness, the para-aramid fiber portion was not dyed and the dyeability was poor, and the quality was marbling and poor. Table 3 shows the results.

Example 2 80 short fibers (1.5 de, 51 mm cut, crimp number = 10 / in, strength = 28 g / de) of copolymerized para-aramid fibers (trade name: Technora, manufactured by Teijin Limited) were used. It was immersed in dimethylsulfoxide heated to ° C and treated for 30 minutes with good stirring. Then, it was washed with hot water of 100 ° C. for 30 minutes, thoroughly washed with water and dried. Next, the treated para-aramid fiber is converted into a short fiber (1.5 de, of meta-aramid fiber (trade name; Conex, manufactured by Teijin Limited))
51 mm cut, number of crimps = 11 / in, strength = 3.6
g / de) and 5% and 95%, respectively, were mixed and twisted by a conventional method to give a 30/2 spun yarn, and then woven into a plain woven fabric. Scouring and heat treatment in the same manner as in Example 1,
In the dyeing bath shown in Table 2, the temperature is raised from atmospheric pressure at a rate of 2 ° C./minute to 160
Stained at 60 ° C for 60 minutes. At this time, the dye is Bas
acryl RedGL (manufactured by BASF) was used. Next, after reduction cleaning was performed in the same manner as in Example 1, final setting was performed. When this flat woven fabric was evaluated for dyeability, quality and dyeing fastness, it was found that it was excellent in dyeability without color unevenness and also in quality. Also,
This plain woven fabric had good dyeing fastness. Table 3 shows the results.

[0030]

[Table 2]

* 4: manufactured by BASF

Comparative Example 2 A short fiber of a meta-aramid fiber was used in the same manner as in Example 2 except that the same para-aramid fiber short fiber as in Example 2 was used and the treatment with dimethylsulfoxide was not carried out. Blending was performed to form a plain fabric, which was scoured, washed with water, dried and dyed. When this plain woven fabric was evaluated for dyeability, grade and dye fastness, it was found that the para-aramid fiber and the meta-aramid fiber were uneven in dyeing condition and the dyeability and grade were poor. Table 3 shows the results.

Comparative Example 3 Short fiber (1.5 de, 51 mm cut, number of crimps = 10 / in, strength = 28 g / de) of copolymerized para-aramid fiber (trade name: Technora manufactured by Teijin Limited) and meta Mixed aramid fiber (made by Teijin Ltd., trademark; Conex) with short fiber (1.5 de, 51 mm cut, crimp number = 11 pieces / in, strength = 3.6 g / de) by an ordinary method. Twisted and then woven into a plain weave. It was scoured and heat-treated in the same manner as in Example 1, then immersed in dimethyl sulfoxide heated to 80 ° C., and stirred for 30 minutes.
Processed for a minute. Then, it was washed with hot water at 100 ° C. for 30 minutes, thoroughly washed with water and dried. Then, the temperature is raised from room temperature at a rate of 2 ° C./min in the same dyeing bath (Table 2) as in Example 2 to obtain 160
Stained at 60 ° C for 60 minutes. At this time, as the dye, Bas
acryl Red GL (manufactured by BASF) was used.

Then, reduction cleaning and final setting were carried out in the same manner as in Example 1. When the dyeability, the quality, and the dyeing fastness of this woven fabric were evaluated, the obtained woven fabric was dyed in the same color with Technora (para-type aramid fiber) / Conex (meta-type aramid fiber). Shrinkage is large (with dimethylsulfoxide treatment, lengthwise-about 20%, weft-about 18% shrinkage), the texture is stiff, it is extremely coarse and hard, and white powder that seems to be an oligomer adheres to the fabric surface, It was of very poor quality. Table 3 shows the results.

[0035]

[Table 3]

[0036]

EFFECTS OF THE INVENTION According to the present invention, even a fiber structure in which para-aramid fibers and other fibers are used in combination can be dyed with good and uniform dyeing property and, at the same time, can be dyed fast. Is excellent and does not deteriorate the quality by dyeing.
Further, since it can be applied when any dye is used, it is possible to obtain fiber structures having various hues.

Claims (4)

[Claims] 1. When dyeing a fibrous structure containing a para-aramid fiber spun yarn, the para-aramid fiber is treated with a polar solvent before spinning and then made into a spun yarn, which is then dyed. A method for dyeing and processing a fiber structure containing a para-aramid fiber spun yarn. 2. The method for dyeing a fiber structure containing a para-aramid fiber spun yarn according to claim 1, wherein the polar solvent is dimethyl sulfoxide. 3. The treatment with dimethyl sulfoxide is 7
The treatment time is 5 minutes or more at a temperature of 0 ° C. or more.
2. A method for dyeing and processing a fiber structure containing the para-aramid fiber spun yarn according to claim 1. 4. The method for dyeing a fiber structure containing a para-aramid fiber spun yarn according to claim 1, wherein the dyeing temperature is 130 ° C. or higher and 200 ° C. or lower. [0001]