JP2555758B2 - Core-sheath composite fiber - Google Patents

Description

TECHNICAL FIELD The present invention relates to a core-sheath composite fiber. More specifically, the present invention relates to a core-sheath composite fiber having functions such as hygroscopicity, antistatic property, antifouling property and deodorant property, and excellent in dyeing fastness such as light resistance and washing.

[Prior Art] Polyamide fibers represented by nylon 6 and nylon 66 have been widely used for clothing due to their excellent strength, abrasion resistance, deep dyeability, and ease of resin processing. There is. Further, by graft-polymerizing a hydrophilic vinyl monomer on polyamide fiber to impart a hydrophilic function such as hygroscopicity, various methods for further improving the wearing comfort of clothes are described in Japanese Patent Publication No. 60-34979. Has been proposed.

On the other hand, dyeing of polyester typified by polyethylene terephthalate was generally performed by a disperse dye. However, as described in JP-B-34-10497, a polymer is a sulfonated aromatic dicarboxylic acid-modified polyester. As a result, it is possible to dye with a cationic dye, and it is also possible to improve color development and to dye polyester fibers with different colors. However, the drawbacks inherent to polyester, such as insufficient abrasion resistance and resin processability, have not been improved, but rather tended to be worse.

In addition, polyamide and polyester as a composite fiber,
Many means of utilizing the advantages of both have been proposed. In order to dye the composite fiber so as to obtain sufficient luminescence, a formulation for coloring both polyamide and polyester, for example,
It was necessary to use dyeing recipes with disperse dyes or mixed dyeing recipes of acid dyes and disperse dyes or cationic dyes.

However, none of these dyeing formulations is practical because the wet fastness or the light fastness of the dyed product is unsatisfactory.

Further, there is a means of graft-polymerizing a hydrophilic vinyl monomer in order to impart hydrophilicity such as hygroscopicity to polyamide or polyester. According to this, the presence of the dye in the polyamide or polyester hinders the graft polymerization, and the dye is decomposed by the graft polymerization initiator, which causes problems such as discoloration and decolorization.
Therefore, it has been essential to carry out these graft polymerizations before the dyeing step.

Further, since the unevenness of the graft polymerization becomes the uneven dyeing as it is, there is a problem that the process control conditions must be strengthened more than necessary.

Furthermore, the dyeing fastness of the graft-polymerized polyamide or polyester is reduced, and in particular, there is a problem that the wet fastness of dark colors such as dark blue is significantly reduced. The current situation is that the use of products is limited and the products are not fully developed.

[Problems to be Solved by the Invention] In view of the above problems, the present invention provides a core-sheath composite fiber having excellent dyeing fastness and color developability, hydrophilic properties such as hygroscopicity, and functions such as deodorant property. The purpose is to provide.

[Means for Solving the Problems] In order to solve the above problems, the present invention has any of the following configurations. That is, a core-sheath composite fiber having a polyamide sheath and a sulfonated aromatic dicarboxylic acid-modified polyester core, wherein the polyamide has 7 × 10 ^{−4 to} 5 × 10 ⁻³ equivalents.
/ g polyamide-containing core-sheath composite fiber, or a core-sheath composite fiber having a polyamide sheath, a sulfonated aromatic dicarboxylic acid modified polyester core, wherein the polyamide has a carboxyl group Is 7 × 10 ^{-4 to} 5 × 10 ^-3 equivalent
/ g Polyamide is included, and the colorant content of the sheath is 0.2% owf
The core-sheath composite fiber is characterized in that the content of the colorant in the core is 10% or less.

 Hereinafter, the present invention will be described in detail.

One of the characteristics of the core-sheath composite fiber of the present invention is a core having polyamide as a sheath component which is difficult to be dyed with a cationic dye, and a sulfonated aromatic dicarboxylic acid modified polyester (hereinafter, modified polyester) which is well dyed with a cationic dye as a core component. It is a sheath composite fiber.

In addition, it is also a feature that the polyamide of the sheath component contains a carbosyl group.

When coloring or dyeing the core-sheath composite fiber, one of the features is to introduce most of a coloring agent such as a pigment or a dye to the modified polyester side which is the core component of the core-sheath composite fiber.

Thus, among the core-sheath composite fibers, substantially only the core portion is colored, because of the difference in the refractive index from the sheath polyamide, the coloring fiber is excellent in color developability and sharpness, and further,
Since the coloring agent is not substantially present in the sheath portion, the dyeing fastness, particularly the wet fastness such as washing and wet rubbing is improved.

The core-sheath composite ratio in the core-sheath composite fiber of the present invention easily forms a uniform and durable sheath component, and from the viewpoint of obtaining the desired color developability without interrupting the color of the colored modified polyester core. , The ratio of polyamide that is the sheath is 20 to 75
It is preferable to set the weight%.

The arrangement of the polyamide sheath and the modified polyester core is preferably basically concentric, but may be eccentric or multi-core as long as the sheath is not too thin and breaks. Further, a modified cross-section yarn can be used as long as the modified polyester core can be covered with the polyamide sheath.

As the method for producing the core-sheath composite fiber of the present invention, first, the polyamide and the modified polyester are separately melted and introduced into a spinning pack part, and a composite flow is formed so as to take a core-sheath structure by a usual method. Then, it is spun from the nozzle.

The spun filament yarn is taken up and oiled at a predetermined speed, and then wound up in a package. Next, the wound yarn is stretched by a draw twister in the usual manner so that desired strength and elongation can be obtained. This drawing may be carried out continuously after winding the spun yarn without winding and winding up. Alternatively, a method may be adopted in which the fiber is taken off at a high speed of 4000 m / min or more and the desired fiber performance is obtained all at once.

A method of selectively coloring the core-modified polyester can be achieved, for example, by spinning and spinning a modified polyester blended with a pigment as the core polymer as described above.

The pigment applicable to the core-sheath composite fiber of the present invention includes Re
nol Yellow SGG-AT, Renol Red SG-AT, Renol Blue A
ZR-AT (manufactured by Bayer Japan K.K.), PESM-1031,
PESM-2245, PESM-2460 (manufactured by Dainichiseika Kogyo Co., Ltd.) and the like, but not limited to these, organic type,
Any inorganic pigment can be used. Withstands spinning temperatures,
As long as stable spinning is possible, not only pigments but also dyes may be used as colorants.

As another method of selectively coloring the modified polyester of the core portion, a method of dyeing with a cationic dye can also be applied. Examples of cationic dyes include Aizen Cath
ilon (Hodogaya Chemical Co., Ltd.), Kayacryl (Nippon Kayaku Co., Ltd.), Estrol, Sumiacryl (Sumitomo Chemical Co., Ltd.)
Made), Diacryl (made by Mitsubishi Kasei Co., Ltd.), Maxilon (made by Ciba Geigy), Astrazon (Bayer Japan Co., Ltd.)
Manufactured by K.K.) and the like, but not limited to these, and dispersed cationic dyes can also be used.

As for the dyeing conditions, the dyeing conditions of ordinary cationic dyes can be applied. The soaping after dyeing is preferably carried out in a warm water bath at 50 ° C to 80 ° C containing an anionic surfactant, though it depends on the concentration of the dye used.

This soaping is carried out in order to easily contain a carboxyl group in the polyamide of the sheath except for the cationic dye contaminated with the polyamide of the sheath and the cationic dye remaining on the surface of the fiber.

In the core-sheath composite fiber of the present invention, in order to obtain a dyed product having good color development, light fastness and washing fastness, the content of the colorant in the sheath is 0.2% owf or less and the colorant in the core is obtained. The content is 10% or less. It is more preferable that the colorant content of the sheath is 0.1% owf or less and the colorant content of the core is 5% or less.

When the content of the colorant in the sheath exceeds 0.2% owf, the fastness to washing and the fastness to light are significantly reduced. Further, if the colorant content of the sheath exceeds 10% of the colorant content of the core, it is difficult to obtain a sufficient level of light fastness.

For this purpose, the soaping after dyeing may be treated with a hot water bath containing an anionic surfactant at 50 ° C to 80 ° C.

The content of the colorant in the core may be set to any level according to the desired degree of coloring. In order to obtain a color developability that can be recognized with the naked eye, in the case of a light dyeing product, generally, the content of the coloring agent is 0.01% owf or more. In the case of deep dyeing products,
In terms of practical use, 50% owf or less is preferable in terms of cost.

The coloring agent content of the sheath portion or the core portion in the present invention is a value in which the weight of the coloring agent contained in the polymer of the sheath portion or the core portion is expressed as a percentage, and, for example, the coloring agent content rate of the sheath portion is A content of 0.2% owf or less means that the content of the coloring agent is 0.02 g or less with respect to 1 g of the polyamide in the sheath portion.

In the present invention, the content of the coloring agent in the sheath or core is determined by the following method.

<Coloring agent content of sheath> Weigh a fixed amount (200 mg) of dyed core-sheath composite fiber or its fabric, and add 30 ml of 30% formic acid 88% solution.
Immerse in the resin for 3 minutes to dissolve the polyamide in the sheath and the dye dyed in it, and use the colorimeter "Spectro Photometer" U-3400.
The absorbance at the maximum absorption wavelength is measured by (Hitachi, Ltd.).

In addition, weigh a certain amount (200 mg) of the sample before dyeing, and keep it at 30 ℃.
A predetermined amount (0.25mg, 0.5mg, 1.0m
Dissolve with the dye of g), determine the absorbance with a colorimeter, and plot the relationship between the absorbance and the dyeing rate of this dye as a calibration curve. Using this calibration curve, the content (a% owf) of the coloring agent in the sheath portion is determined from the value of the absorbance of the sheath polyamide in the actual dyeing.

<Content of Colorant in Core> First, the core-sheath composite fiber or the polyamide in the sheath is dissolved and removed, and then washed with water to obtain a dyed fiber component of the core-modified polyester. A fixed amount (100 mg) of the dyed fiber was weighed, put in 30 ml of a phenol / ethane tetrachloride mixed solution (weight ratio 3: 2) and completely dissolved at about 60 ° C., and then the maximum absorption wavelength was measured by the colorimeter. Measure the absorbance at. Further, using the modified polyester fiber taken out from the sample before dyeing, a calibration curve showing the relationship between the absorbance and the dyeing rate was obtained in the same manner as described above, and from this calibration curve, the colorant content (b % Owf).

From the colorant content of the sheath (a% owf) and the colorant content of the core (b% owf), the ratio of the colorant content of the sheath to the colorant content of the core was calculated by (a / b) x 100. Calculate the ratio of

The polyamide constituting the sheath portion of the core-sheath conjugate fiber of the present invention contains a carboxyl group in a predetermined amount described later.

To allow the sheath polyamide to contain a carboxyl group, heat treatment is carried out in an aqueous solution containing a hydrophilic vinylcarboxylic acid such as acrylic methacrylic acid and a graft polymerization initiator,
This can be achieved by graft-polymerizing a hydrophilic vinylcarboxylic acid on the polyamide.

The hydrophilic vinyl carboxylic acids such as acrylic acid and methacrylic acid may be used alone or in combination of two or more. The graft polymerization initiator may be an organic peroxide such as benzoyl peroxide, but it is more selective to use ammonium persulfate and sodium formaldehyde sulfoxylate in combination to graft-polymerize the hydrophilic vinylcarboxylic acid onto the sheath polyamide. It is possible and preferable.

The graft polymerization step is preferably performed before the dyeing step from the viewpoint of preventing the dyeing of the cationic dye on the sheath polyamide and increasing the dyeing fastness.

The amount of carboxyl groups contained in polyamide is 7 x 10
^{-4 to} 5 x 10 ^-3 equivalent / g of polyamide, preferably 1
It is a polyamide of x10 ^-3 to 4x10 ^-3 equivalent / g.
If the amount of carboxyl group is less than 7 × 10 ^-4 equivalent / g polyamide, it is difficult to obtain sufficient performance functions such as hygroscopicity and deodorant. Conversely, if it exceeds 5 × 10 ^-3 equivalent / g polyamide, it becomes sticky. It has a strong feeling, the dyeing fastness is poor, and the sheath portion is easily peeled off, resulting in an unsatisfactory product.

In the present invention, the amount of carboxyl groups is obtained as follows.

{1- (1/1 + gr)} / M (equivalent / g polyamide) where gr is the graft ratio (%) / 100 and M is the molecular weight of the hydrophilic vinylcarboxylic acid monomer.

The sulfonated aromatic dicarboxylic acid-modified polyester component side of the core of the composite fiber of the present invention does not show a weight increase before and after the graft polymerization treatment under the above conditions. Is not graft-polymerized.

In the present invention, the carboxyl group means free --COOH.
In addition, it means any of the salt states in which hydrogen ions are replaced with other cations.

The carboxyl group introduced by graft polymerization as described above can be arbitrarily converted to a metal salt or a quaternary ammonium salt depending on the desired performance. For example, Na,
When the carboxyl group is replaced with an alkali metal ion such as K or Li, hydrophilic properties that are effective in improving hygroscopicity, antistatic property, antifouling property, hardly melting property and the like are exhibited. Further, when substituted with a quaternary ammonium ion such as lauryldimethylbenzylammonium chloride ion, tetrabutylammonium bromide ion, or octylpyridinium chloride ion, antibacterial and antifungal performance is exhibited. Further, when the dyeing is completed, that is, in the state of free carboxylic acid, ammonia deodorizing performance is exhibited.

Depending on the combination of ions that replace the carboxyl group,
It is also possible to express different functions at the same time, and it can be appropriately selected according to the purpose.

The substitution treatment of these carboxyl groups can be carried out by a hot water bath treatment at 40 to 90 ° C. containing a necessary chemical. For example, in the case of Na salt, it is 3-12 of basic sodium salt such as soda ash.
It may be treated at 80 ° C for 30 minutes in an aqueous solution of g / (when the bath ratio is 1:30). When all carboxyl groups are Na salts,
The required amount of the basic sodium salt is about 5 times the equivalent amount of the carboxyl groups contained in the sheath polyamide. Further, when the amount is equal to or less than the equivalent of the carboxyl group contained in the sheath polyamide, the polyamide has both a sodium salt of a carboxylic acid and a free carboxylic acid, and hydrophilic performance and ammonia deodorizing performance can be imparted.

The polyamides used in the present invention are typically poly ε-caprolamide (nylon 6) and polyhexamethylene adipamide (nylon 66), but other polymerizable monomers such as laurolactam, sebacic acid, para A polyamide obtained from xylylenediamine, isophthalic acid or the like, or a copolyamide thereof may be used.

Further, a modified polyamide in which a compound having a sulfone group is bonded to a polyamide chain or a part of the terminal, or a compound having a sulfone group, in which a sulfonated aromatic dicarboxylic acid is in a free acid state or an alkyl ester The modified polyamide obtained by adding and copolymerizing in this state may be used.

Further, as a typical example of the sulfonated aromatic dicarboxylic acid, 5-sulfoxyisophthalic acid represented by the following chemical formula or a salt thereof can be mentioned.

When a polyamide copolymer modified with a sulfonated aromatic dicarboxylic acid is used, the skeleton is formed from the viewpoint of exerting the original effect of the modified polyamide and not impairing the preferable mechanical properties of the polyamide. It is preferably about 0.25 to 3 mol% with respect to the polyamide monomer.

The polyamide may contain a matting agent such as titanium oxide, but in order to sufficiently transmit the color of the core polyester and obtain excellent color development, the matting agent and other pigments should not be used. , It is preferable that it is not substantially contained.

Further, these polyamides may contain an antistatic agent, a heat-resistant agent, a light-resistant agent, etc., as long as they do not significantly reduce the light transmittance.

In the core-sheath composite fiber of the present invention, the modified polyester used as the core is a modified polyester in which a compound having a sulfone group is contained in a part of the chain or end of the polyester. For example, JP-B-34-10497 It is possible to use those described in the publication. This modified polyester is a modified polyester obtained by copolymerizing polyethylene terephthalate, polybutylene terephthalate or a copolymerized polyester containing these as a main component with a sulfonated aromatic dicarboxylic acid or a salt thereof.

Typical examples of such a sulfonated aromatic dicarboxylic acid include 5-sulfoxyisophthalic acid represented by the above chemical formula or a salt thereof.

These dicarboxylic acids are added at the time of polyester polymerization in the form of a free acid or an alkyl ester and are copolymerized to form a modified polyester.

The copolymerization amount of this sulfonated aromatic dicarboxylic acid exerts the desired effect of the modified polyester, and does not cause an unfavorable phenomenon such as a significant reduction in mechanical properties due to disorder of the crystal structure of the modified polyester. In addition, it is preferable that the amount of terephthalic acid is 0.5 to 6 mol%.

It should be noted that these modified polyesters may contain an antistatic agent, a light resistance agent, a heat resistance agent, a matting agent and the like.

The core-sheath composite fiber of the present invention uses a modified polyester for the core, and as described above, the content of the coloring agent in the sheath is 10% or less of the content of the coloring agent in the core, in other words, Since 90% or more of the colorant is contained in the core portion, the core portion of the modified polyester is sufficiently colored, but the sheath portion of the polyamide is hardly colored.

Therefore, when the sheath polyamide is selectively graft-polymerized after the dyeing step, a coloring agent that inhibits the graft polymerization, that is, a dye or a pigment is scarcely present in the sheath polyamide, so that the graft polymerization is sufficiently efficiently achieved. be able to.

Graft-polymerized polyamide generally lowers the level of light fastness and wash fastness, but in the case of the core-sheath composite fiber of the present invention, the coloring agent on the polyamide component side of the grafted sheath is used. , That is, 10 dyes and pigments
%, It is possible to make the deterioration of the fastness extremely small.

In addition, the colored and graft-polymerized core-sheath composite fiber of the present invention has the inherent abrasion resistance of polyamide and also has the property of being easily processed into a resin. In addition, since it has a modulus intermediate between polyamide and polyester, it is possible to impart a favorable tension and stiffness to the fabric, and as a secondary effect, the dimensional stability when wet, which is a defect of polyamide. The improvement effect and the wrinkle prevention effect can also be exhibited.

 Hereinafter, further details will be described with reference to examples.

[Example] Each evaluation method is shown below.

<Graft ratio> The dyed sample (before the graft polymerization process) and the weight increase rate after the graft polymerization process were expressed as%. Each sample was measured for absolute dry weight.

<Hygroscopicity> The dried product was allowed to stand in an atmosphere of 20 ° C and 65% RH for 24 hours, then weighed and calculated by the following formula.

<Ammonia gas adsorbability> 0.2 ml of 30% ammonia water was dropped into a 500 ml wide-mouthed bottle with a stopper, 20 g of an object to be treated was then added, and the bottle was sealed. Then, after leaving it for 20 minutes, the residual ammonium odor was smelled and evaluated by the following three grades.

×: Intense residual ammonia odor: Bad Δ: Medium residual ammonia odor: Slightly bad ○: Slight residual ammonia odor: None <Good><Antibacterialproperties> AATCC Test Method 90 (1977), clear zone width ( mm).

<Lightfastness> Measured by the method of JIS L 0842.

<Washing fastness> Measured by the method of JIS L 0844. However, the color fading was measured by classifying the degree of color fading as compared with the color difference observed between the color charts of the gray scale for contamination.

(Example 1, Comparative Example 1) A polyethylene terephthalate raw material composed of ethylene glycol and terephthalic acid was mixed with 5-sulfoxyisophthalic acid in an amount of 1.5 mol% based on terephthalic acid by a conventional method.
Add and polymerize to obtain orthochlorophenol intrinsic viscosity IV
0.64 of modified polyethylene terephthalate (hereinafter, modified polyester) was obtained.

The modified polyester and Nylon 6 having a sulfuric acid relative viscosity of 2.62 which is substantially free of titanium oxide are subjected to an extruder type composite spinning machine, melted separately, then weighed in equal amounts, and the modified polyester is mixed in the composite spinning pack section. Form a composite stream so that the core is the core and the nylon 6 is the sheath, and discharge it, take it off at a speed of 1500 m / min, then heat set it with a stretching heat roller at 160 ° C, and wind it at 4000 m / min, 70 Denier 24
A filament yarn was obtained.

This drawn yarn was applied to the warp and weft, and the plain weave (warp density 11
8 yarns / inch, weft density 85 yarns / inch) were woven. This plain weave is "Sandet" G-29 (manufactured by Sanyo Kasei Co., Ltd.) 2 g /
, Soda ash 5g /, "Detrol" WR-14 (manufactured by Meisei Chemical Industry Co., Ltd.) 2g / in a treatment bath at 98 ° C for 20 minutes, desizing and scouring, and then drying, 170 ° C Was intermediately set to obtain a sample fabric for dyeing and graft polymerization.

The sample cloth was treated with a cationic dye "Diacryl Red GRL-N" c
Onc (manufactured by Mitsubishi Kasei Co., Ltd.) 0.5% owf and acetic acid (80%) 0.5cc / auxiliary as a bath were dyed at 120 ° C. for 30 minutes (sample for Example 1).

As a comparison, the sample cloth was mixed and dyed under the following conditions. Cationic dye "Diacryl Red GRL-N" (manufactured by Mitsubishi Kasei Co., Ltd.) 0.25% owf, acid dye "Diacid Azo.
Rubiol 3GS "250% (manufactured by Mitsubishi Kasei Co., Ltd.) 0.25% ow
f, "Ospin 700-CD" as an auxiliary agent (Tokai Oil Co., Ltd.)
Dyed in a bath of 0.5% owf and 0.5 cc / acetic acid for 30 minutes at 120 ° C. (sample for Comparative Example 1).

20% of mixed vinylcarboxylic acid monomer in which these colored fabrics are mixed with acrylic acid and methacrylic acid in a weight ratio of 1: 1.
Wf, ammonium persulfate 1% owf, and sodium formaldehyde sulfoxylate 3% owf were separately put into an aqueous solution, and each sample was placed separately, and heat-treated in a bath at 75 ° C. for 30 minutes to perform graft polymerization. Then, after washing with hot water, washing with water, drying, and conditioning at 20 ° C. and 65% RH, the weight increase rate before and after the graft polymerization process was calculated.

Then, in a 10 g / soda ash aqueous solution at 80 ° C. for 30 minutes,
The mixture was heat-treated in a bath at a bath ratio of 1:30, graft-polymerized, and the carboxyl groups introduced into the fiber were replaced with Na.

Next, the Na-substituted fabric was washed with water and dried, and then each sample was divided into 3 equal parts, and 1 part was placed in an aqueous solution containing 20% owf of acetic acid.
The mixture was treated at 0 ° C for 30 minutes to convert the carboxyl group into a carboxylic acid. The remaining 1 part was treated with an aqueous solution containing 10% owf of lauryldimethylbenzylammonium chloride as a pure component at 80 ° C,
After treatment for 30 minutes, the carboxy group was lauryldimethylbenzylammonium chloride.

In this manner, samples having three types of carboxyl groups, Na salt type, acid type, and quaternary ammonium salt type were obtained (Example 1 and Comparative Example 1).

For the obtained sample, the dye exhaustion rate (core portion, sheath portion),
Graft ratio, moisture absorption ratio, ammonia gas adsorption performance, antibacterial property evaluation, light resistance, and washing fastness were evaluated. The results are shown in Table 1.

As is clear from the results shown in Table 1, the sample obtained in Example 1 has not only the desired functionality but also high light resistance and washing fastness. However, in Comparative Example 1 in which a large amount of dye is present on the polyamide side, graft polymerization is hardly achieved and desired functionality cannot be obtained.

The core-sheath composite yarn used in the examples had a core-sheath composite ratio of 1: 1 and the moisture absorption rate of the raw material fiber which was not subjected to the grafting treatment or the Na chlorination treatment was about 2%.

Since modified polyester is present in the sheath, the texture of these fabrics has the unique tension and waist of polyester,
It was more preferable than nylon 6 alone.

(Example 2) To a polyethylene terephthalate raw material consisting of ethylene glycol and terephthalic acid, 5-sulfoxyisophthalic acid was added in an amount of 1.5 mol% with respect to terephthalic acid by a conventional method, and the mixture was polymerized to obtain an orthochlorophenol intrinsic viscosity IV0.64.
A modified polyester of was obtained.

2.0 wt% of Renol Blue A2R-AT (manufactured by Hoechst Japan Ltd.) was uniformly blended with the above modified polyester to obtain a colored modified polyester polymer.

The colored modified polyester and nylon 6 having a sulfuric acid relative viscosity of 2.62 which is substantially free of titanium oxide are subjected to an extruder type composite spinning machine and melted separately,
Equal amounts are weighed, and a composite stream is formed in the composite spinning pack so that the modified polyester is the core and the modified nylon 6 is the sheath, and the mixture is discharged at a speed of 1500 m / min. Heat set at 160 ℃, wind up at 4000m / min, 70
A drawn yarn of denier 24 filament was obtained.

This drawn yarn was applied to the warp and weft, and the plain weave (warp density 11
8 yarns / inch, weft density 85 yarns / inch) were woven. This plain weave is "Sandet" G-29 (manufactured by Sanyo Kasei Co., Ltd.) 2 g /
, Soda ash 5g /, "Detrol" WR-14 (manufactured by Meisei Chemical Industry Co., Ltd.) 2g / in a treatment bath at 98 ° C for 20 minutes, desizing and scouring, and then drying, 170 ° C I did an intermediate set.

The colored fabric was then subjected to the same graft polymerization process and substitution process as in Example 1.

For the obtained sample, the dye exhaustion rate (core portion, sheath portion),
Graft ratio, moisture absorption ratio, ammonia gas adsorption performance, antibacterial property evaluation, light resistance, and washing fastness were evaluated. The results are also shown in Table 1.

As is clear from the results of Table 1, the sample obtained in Example 2 has desired functionality, light resistance, and fastness to washing. However, in Comparative Example 1 in which a large amount of dye is present on the polyamide side, graft polymerization is hardly achieved and desired functionality cannot be obtained.

Due to the presence of the modified polyester in the sheath portion, the texture of these fabrics had the peculiar tension and waist of polyester, which was more preferable than nylon 6 alone.

(Example 3) Moisture absorption rate of a sample obtained by subjecting the cloth subjected to the intermediate set to a graft polymerization process without dyeing in Example 1 and carrying out the same carboxyl group substitution treatment as in Example 1,
Ammonia gas adsorption performance and antibacterial property were evaluated. The results are also shown in Table 1.

(Comparative Examples 2 and 3) A plain woven fabric similar to that of Example 1 was woven using 70 denier and 24 filament drawn yarn of nylon 6 obtained by a conventional method,
Desizing and scouring, intermediate setting, a part was subjected to graft polymerization after dyeing (Comparative Example 2), the remaining part was grafted without dyeing, and then dyed (Comparative Example 3). The same replacement process was performed.

 However, the dyeing conditions were as follows.

Acid dye "Diacid Azo.Rubine 3GS" 250% (manufactured by Mitsubishi Kasei Kogyo Co., Ltd.) 0.5% owf and 0.5 cc / acetic acid as an auxiliary agent were dyed at 100 ° C for 30 minutes.

For the obtained sample, the dye exhaustion rate (core portion, sheath portion),
Graft ratio, moisture absorption ratio, ammonia gas adsorption performance, antibacterial property evaluation, light resistance, and washing fastness were evaluated. The results are also shown in Table 1.

As is clear from the results of Table 1, as compared with Examples 1 and 2, those having a large amount of dye on the polyamide side as in Comparative Example 2 hardly achieved the graft polymerization, and the desired functionality was obtained. Absent.

When dyeing after graft polymerization as in Comparative Example 3, the graft polymerization is sufficiently achieved and desired functionality is obtained, but the light resistance and the fastness to washing are insufficient and the development as a product is difficult. Have difficulty.

[Effects of the Invention] The core-sheath composite fiber of the present invention retains excellent light fastness and washing fastness, and also has hydrophilic properties such as moisture absorption and antistatic property depending on the type of carboxyl group in the fiber. Or
It is possible to easily impart functions such as ammonia deodorizing property and further antibacterial property.

Since the core-sheath composite fiber according to the present invention has such functions and characteristics, it can be applied to the outer and inner materials for spring and summer in the field which has been difficult to develop with synthetic fiber materials due to lack of moisture absorption performance. Become. For example, sports slacks such as golf, jackets for spring and summer, skirts,
Suitable for workwear such as office wear and nurse wear.

Furthermore, it is also suitable for sports linings, general clothing linings, etc., which were difficult to develop due to the lack of dimensional stability of nylon.

By adding ammonia deodorant or antibacterial performance, bedding such as sheets, futon, futon cover,
In particular, it is also suitably used for hospitals or hospital curtains, diaper covers, and the like.

Claims (5)

(57) [Claims] 1. A core-sheath composite fiber having a polyamide sheath and a sulfonated aromatic dicarboxylic acid-modified polyester core, wherein the polyamide has a carboxyl group of 7 × 10 ^{−4 to} 5.
A core-sheath composite fiber characterized by containing x10 ^-3 equivalent / g of polyamide. 2. A core-sheath composite fiber comprising a polyamide as a sheath and a sulfonated aromatic dicarboxylic acid modified polyester as a core, wherein the polyamide has a carboxyl group of 7 × 10 ^{−4 to} 5.
A core-sheath composite fiber containing x10 ^-3 equivalents / g of polyamide, wherein the content of the colorant in the sheath is 0.2% owf or less and 10% or less of the content of the colorant in the core. 3. The core-sheath composite fiber according to claim 1, wherein the colorant is a cationic dye. 4. The core-sheath composite fiber according to claim 1, wherein the colorant is a pigment. 5. The core-sheath composite fiber according to claim 1, wherein the sheath portion is 20 to 75 wt%.