JPH0772397B2 - Dyed composite fiber - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention is excellent in light fastness and washing fastness of dyeing,
In addition, the present invention relates to a dyed composite fiber capable of obtaining a clear color.

[Prior Art] Polyamide fibers represented by nylon 6 and nylon 66 have been used in many clothing applications due to their excellent strength, abrasion resistance, deep dyeability, and ease of resin processing. ing. Above all, nylon for sports outerwear, especially ski wear, where color development and resin processability are particularly required, was the exclusive venue.

However, with the recent diversification of fashion and the expansion of uses, clear colors are required for ski wear, swimwear, casual wear and the like. The greatest advantage of polyamide is that it can be dyed in deep colors with acid dyes, and it can be dyed in vivid colors.On the contrary, in vivid color dyeing, the discoloration due to light is remarkable and the dyeing fastness is poor. However, it was considered to be difficult to put into practical use for applications requiring clear colors.

On the other hand, polyester typified by polyethylene terephthalate has generally been dyed with a disperse dye for many years, and its color forming property and transfer sublimation property have been improved, but there are still many parts that do not match nylon in depth of vivid color. . further,
Due to its molecular structure and chemical structure, polyester is vulnerable to abrasion and resin processability is not sufficient. The dyeability of this polyester can be greatly improved by dyeing the polymer with a sulfonated aromatic dicarboxylic acid-modified polyester as described in JP-B-34-10497, and dyeing this with a cationic dye, The above-mentioned drawbacks inherent to polyester (insufficient abrasion resistance and resin processability) are not improved, but rather tend to be worse.

Further, many means have been proposed for utilizing the advantages of both of the composite spinning of polyamide and polyester, but in that case, the dyeing is a disperse dye dyeing in which both are dyed, or an acid dye and a cationic dye or Mixed dyeing with disperse dyes is required to obtain sufficient color development. However, the dyed product obtained by the former disperse dyeing does not satisfy the practical level because the washing fastness of polyamide is insufficient. Further, the dyed product obtained by the latter mixed dyeing has not been put into practical use because the problem of poor light fastness on the polyamide side, which is dyed in a bright color, becomes a problem.

[Problems to be Solved by the Invention] The present invention provides a dyed product dyed in a vivid color, which is excellent in color developability, light resistance, washing resistance and abrasion resistance, and is strong and capable of being resin-dyed. The main purpose is to provide a composite fiber.

[Means for Solving the Problems] The present invention provides a core-sheath type in which polyamide is arranged in a sheath portion, sulfonated aromatic dicarboxylic acid-modified polyester is arranged in a core portion, and substantially only a cationic dye is dyed as a dye. The conjugate fiber is a dyed conjugate fiber characterized in that the dyeing rate of the sheath is 10% or less and 0.2% owf or less of the dyeing rate of the core.

One of the features of the present invention is a core-sheath type composite fiber having a composite structure that covers a sulfonated aromatic dicarboxylic acid modified polyester (hereinafter abbreviated as modified polyester) that is dyed well with a cationic dye with a polyamide that is difficult to dye with a cationic dye. It is to be.

Another feature is that this core-sheath type composite fiber is dyed substantially only with a cationic dye, and the dyeing rate of the sheath part and the core part is set to a specific value.

As described above, when the core-sheath type composite fiber is dyed substantially only with the cationic dye, the dye is sufficiently dyed on the core portion of the modified polyester, but the polyamide sheath portion is hardly dyed. However, the dyed composite fiber can exhibit sufficient color development and dyeing fastness.

For these effects, the dyeing rate of the sheath is set to 10% or less, preferably 5% or less of the dyeing rate of the core, and the dyeing rate of the sheath is 0.2%. It is important that the amount is owf or less, preferably 0.1% owf or less, and more preferably 0.05% owf or less.

That is, by satisfying this dyeing rate condition, a dyed product having good color development, light fastness and washing fastness can be obtained. If the dyeing rate of the sheath exceeds 0.2% owf, the fastness to washing and the fastness to light will remarkably decrease. Also,
Even if the dyeing ratio is 0.2% owf or less, if the dyeing ratio of the core is more than 10%, it is difficult to obtain a sufficient level of light fastness.

The dyeing rate of the core may be set to any level according to the desired degree of dyeing. In order to obtain a color development that can be recognized with the naked eye, in the case of a light dyeing product, generally, a dye dyeing rate of 0.01% owf or more should be taken. Further, in the case of a deep dyeing product, a dyeing rate of 50% owf or less is preferable from a practical viewpoint in terms of cost.

The dyeing rate of the sheath or core in the present invention is a value representing the amount of dye dyed to the polymer of the sheath or core as a percentage, and for example, the dyeing rate of the sheath. Is less than 0.2% owf means that the amount of dye adhering to 1 g of polyamide in the sheath is 0.002 g or less.

The dyeing rate of the sheath or core may be obtained by the following method.

Dye-dyeing rate of the sheath: Weigh a fixed amount (200 mg) of the dyed composite fiber or its fabric and soak it in 30 ml of 30% formic acid 88% solution for 3 minutes. The dye dyed in Example 1 is dissolved, and the absorbance at the maximum absorption wavelength is measured by a colorimeter (U-3400 "Spectro Photometer" manufactured by Hitachi Ltd.). Also, weigh a fixed amount (200 mg) of the sample before dyeing, dissolve it with a predetermined amount (0.25 mg, 0.5 mg, or 1.0 mg) of dye in 30 ml of 30% formic acid 88% solution, and measure the absorbance with a colorimeter. Then, the relationship between the absorbance and the dyeing rate of this dye is plotted as a calibration curve. With this calibration curve, the value of the dyed amount is obtained from the value of the absorbance of the sheath polyamide in the actual dyeing described above.

Dyeing rate of core: First, after dissolving and removing the polyamide in the sheath of the composite fiber or its products, the dyed fiber of the core-modified polyester is obtained by washing with water.
A fixed amount (100 mg) of the dyed fiber was weighed, and phenol /
Put in 30 ml of ethane tetrachloride mixed solution (weight ratio 3: 2) at 60 ℃
After being completely dissolved in a certain degree, the absorbance at the maximum absorption wavelength is measured by the same colorimeter as described above. Further, using the modified polyester fiber taken out from the sample before dyeing, in the same manner as described above, a calibration curve showing the relationship between the absorbance and the dyeing rate is obtained, and from this calibration curve, the core portion modification in the actual dyeing is performed. Obtain the value of the dyed amount of polyester.

Then, from the values of the dye dyeing amount of the sheath portion and the core portion (a% owf and b% owf, respectively, in order), (a / b) × 100
The dyeing ratio of the sheath to the core is calculated by the formula

Polyamide used in the sheath portion in the present invention is typically poly ε-capramide (nylon 6) and polyhexamethylene adipamide (nylon 66), but other polymerizable monomers such as laurolactam, A polyamide obtained from sebacic acid, paraxylylenediamine, isophthalic acid or the like, or a copolyamide thereof may be used.

These polyamides may contain a matting agent such as titanium oxide, but in order to sufficiently transmit the color of the core polyester to obtain excellent color development, a matting agent, other pigments, etc. Is preferably substantially not included.

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.

The modified polyester used for the core in the present invention is a modified polyester in which a compound having a sulfone group is contained in a part of the chain or terminal of the polyester.
-10497. This modified polyester is a modified polyester obtained by copolymerizing polyethylene terephthalate, polybutylene terephthalate or a copolymerized polyester containing these as the main component with a sulfonated aromatic dicarboxylic acid or a salt thereof.

A typical example of the sulfonated aromatic carboxylic acid is 5-sulfoxyisophthalic acid represented by the following chemical formula or a salt thereof.

These dicarboxylic acids are added in the state of free acid or in the state of alkyl ester during the polymerization of polyester and copolymerized to form a modified polyester. The copolymerization amount of the sulfonated aromatic dicarboxylic acid is preferably about 0.5 to 6 mol% with respect to terephthalic acid. If this copolymerization amount is too low, it is difficult to obtain the desired effect of the modified polyester. On the contrary, if the copolymerization amount is too high, the crystal structure of the modified polyester is disturbed and undesired phenomena such as a significant decrease in mechanical properties occur.

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 ratio of the polyamide and the modified polyester can be arbitrarily set within the range where the effect of the present invention is not lost, but the polyamide ratio is preferably 20 to 75% by weight. If the polyamide ratio is too low, it is difficult to form a uniform coating, and moreover,
During the processes such as knitting, weaving, dyeing and finishing, the sheath is often torn and the commercial value is lost. On the other hand, if it is too high, the color of the dyed modified polyester core is interrupted and it is difficult to obtain the desired color developability.

The arrangement of the polyamide sheath portion and the modified polyester core portion is basically preferably on a concentric core sheath, but may be eccentric or multi-core as long as the sheath portion is too thin and is not broken. In addition, if it is possible to cover the modified polyester core portion with the polyamide sheath portion, a deformed yarn can be used.

This core-sheath type composite fiber may be made into a product by yarn-forming, knitting, weaving, and dyeing by a conventional method.

First, the polyamide and the modified polyester are separately melted, introduced into a spinning pack portion, formed into a composite stream so as to have a core-sheath structure by a usual method, and spun from a nozzle.

The spun filament yarn is taken up and oiled at a predetermined speed and then wound up in a package. Next, in order not to obtain desired strength and elongation, the once wound yarn is drawn by a draw twister as usual. This drawing may be carried out continuously after winding the spun yarn without winding and then winding.
Further, a method may be adopted in which the desired fiber performance is obtained all at once at a high speed of 4000 m / min or more.

As the direct spinning drawing method, for example, spun yarn is 1000 to 5000
Examples include a method in which m / min is collected, followed by stretching, and stretching and heat setting at 3000 to 5500 m / min.

The obtained conjugate fiber is dyed with a cationic dye by an ordinary method at an optional step thereafter.

Examples of this cationic dye include "Aizen Cathilo
n "(Hodogaya Chemical Co., Ltd.)," Kayacryl "(Nippon Kayaku Co., Ltd.)," Estrol, Sumiacryl "(Sumitomo Chemical Co., Ltd.)," Diacryl "(Mitsubishi Kasei Co., Ltd.) )
), "Maxilon" (Ciba Geigy Co., Ltd.), "Astra
Examples of the dyes include crown dyes such as zon ″ (manufactured by Bayer Japan Co., Ltd.), but not limited to these, and dispersion type cationic dyes may be used. In a small amount within a range that does not impair the effects of the present invention. If necessary, other dyes may be used in combination.

The dyed composite fiber according to the present invention is particularly suitable for clothing products that are repeatedly washed, but can also be used for interior products such as carpets and car seats.

[Operation] Since the modified polyester is used for the core of the polyester-polyamide core-sheath composite fiber according to the present invention and the core is dyed substantially only with the cationic dye, the core of the modified polyester is sufficiently dyed. However, the polyamide sheath is almost undyed.

However, the dyed composite fiber has sufficient color development. This is because, even if the sheath is not dyed, the dye molecules are extremely likely to move inside the polyamide sheath, so even if the dye concentration is the same, the dye that should originally be dyed on the polyamide sheath is exhausted by the modified polyester. The coloring property is enhanced, and the coloring of the core is recognized as the coloring of the entire composite fiber without being substantially hindered by the polyamide of the sheath, and as a result, a sufficient level of clear coloring is obtained. It is thought to be because it is done.

Further, sufficiently excellent light fastness and washing fastness are exhibited. It is considered that this is because the polyamide sheath is scarcely dyed, and therefore the phenomenon of poor dyeing fastness due to the fading of the dye in the polyamide due to light irradiation or washing is hardly seen. Therefore, the light resistance and the fastness to washing in vivid colors can be set to high levels that cannot be achieved with polyamide fibers.

Furthermore, since the polyamide having a low refractive index covers the surface of the modified polyester, the surface reflection is reduced and the depth of color is increased.

On the other hand, conventionally, when dyeing such a core-sheath composite structure fiber, the condition for dyeing both the core and the sheath is taken as described above in order to improve the color developability. Dyeing or mixed dyeing in which an acid dye that dyes polyamide and a cationic dye or a disperse dye that dyes modified polyester are used together has been performed. In this conventional method,
Since the polyamide part that becomes the sheath is also sufficiently dyed,
Although it is sufficiently excellent in color development, the polyamide sheath has poor light fastness and washing fastness, and the dyeing fastness of the composite fiber as a whole is at an insufficient level.

Moreover, the dyed conjugate fiber according to the present invention has abrasion resistance and resin processing easiness which polyamide originally has. In addition, by having 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 effect of improving dimensional stability against water, which is a defect of polyamide. And the wrinkle-proof effect can also be exhibited. .

Due to having such characteristics as well, the conjugate fiber according to the present invention exerts a particularly remarkable effect in the cloth for clothes used for repeated washing. Of course, even in car seats and carpets that are washed infrequently, excellent color development that has never been achieved,
A clear product can be obtained. Further, the polyamide serves as a sheath to obtain a depth of color which is not found in the conventional cationic dyeable polyester.

Example 1 Example 1 A polyethylene terephthalate raw material composed of ethylene glycol and terephthalic acid was added with a catalyst in the usual manner, and 5-
1.5 mol% of sulfoxyisophthalic acid was added to terephthalic acid and the mixture was polymerized to obtain a modified polyethylene terephthalate (abbreviated as modified polyester) having an intrinsic viscosity (IV) of orthochlorophenol of 0.64.

This modified polyester and nylon 6 (sulfuric acid relative viscosity of 2.62) which does not substantially contain titanium oxide are subjected to an extruder type composite spinning machine, melted separately, and then weighed in equal amounts, and at the composite spinning pack section. A composite flow is formed so that the modified polyester is the core and the nylon 6 is the sheath, and the composite flow is discharged and collected at a speed of 1500 m / min, followed by heat setting with a stretching heat roller (160 ° C), at 4000 m / min. It was wound up to obtain a drawn yarn of 70 denier 24 filament.

This drawn yarn is used as a warp and a weft to produce a plain woven fabric (warp density 118
Weaving was carried out with a book / 2.54 cm and a weft density of 85 / 2.54 cm. 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, drying, 170 ° C The intermediate setting was carried out to prepare a dyeing sample cloth.

The sample cloth was treated with a cationic dye: "Diacryl Red GRL-
Dyeing was carried out for 30 minutes at 120 ° C. in a bath of N ″ conc (manufactured by Mitsubishi Kasei Co., Ltd.) 0.5% owf and 0.5 cc / acetic acid (80%) as an auxiliary agent (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. R
ubiol 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. (Comparative Example 1).

From the obtained dyed fabric, the dye dyeing ratio of the sheath portion and core portion of the constituent composite fiber was measured under the condition of the maximum absorption wavelength of 537 nm, and the coloring property, light fastness and washing fastness were also measured.

The results are shown in Table 1.

Coloring property: A multi-light source spectrocolorimeter (manufactured by Suga Test Instruments Co., Ltd.) was used to measure the color under the condition of a C light source of 65 ° and the L value was displayed. When the color developability is poor, the color is whitish and the L value is high.

Light fastness: Measured by the method of JIS L0842.

Washing fastness: Measured by the method of JIS L0844. 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.

As shown in the results of Table 1, the dyed core-sheath type composite fiber according to the present invention was excellent in dyeing fastness and excellent in color development despite the presence of the polyamide layer on the fiber surface. . On the other hand, in the case of Comparative Example 1 by the mixed dyeing, the dyeing fastness, especially the color fading at the time of washing was poor, and the product did not satisfy the practical level.

-Example 2 With respect to the dyed fabric obtained by dyeing the sample fabric for dyeing obtained in Example 1 under the following conditions, the dye dyeing ratio of the sheath portion and the core portion of the constituent composite fiber was maximized. Absorption wavelength 63
Measured under the condition of 2 nm, its color development, light fastness,
The washing fastness was measured in the same manner as in Example 1, and the result was evaluated as the second value.
It is shown as Example 2 in the table.

Cationic dye "Kayacryl Black R-ED" (Nippon Kayaku Co., Ltd.) 10% owf, acetic acid (80%) 0.5cc /, 45 at 120 ° C
Stain for minutes, then "Luckor PSK" (Meisei Chemical Co., Ltd.)
Made: Anionic activator) 0.5 g /, acetic acid (80%) 0.2 g /
Soaping was performed at 60 ° C for 20 minutes, followed by washing with water and drying.

In addition, as a comparison, a dyed sample fabric is produced by melt spinning using only the same modified polyester as used in Example 1, and directly spinning, weaving, and scouring in the same manner as in Example 1, and using the same cation as above. Dyeing and soaping were performed to manufacture a dyed fabric. The dyeing characteristics were measured in the same manner as in Example 1, and the results are also shown in Table 2 as Comparative Example 2.

As shown by the results in Table 2, the dyed core-sheath type composite fiber according to the present application was smaller in L value than the product of Comparative Example 2 and a dyed product with depth was obtained. Moreover, the dyeing fastness was excellent despite the presence of the polyamide layer on the fiber surface.

Example 3 The same nylon 6 and modified polyethylene terephthalate as in Example 1 were used, and the composite ratio of nylon 6 was 10, 2 respectively.
Direct spinning and drawing were carried out in the same manner as in Example 1 except that the content was changed to 5, 50, 75 and 90% by weight to obtain a 40-denier 12-filament composite fiber yarn. After knitting these fiber yarns into 28-gauge half tricots, they were dyed with "Diacryl Red GRL-N" (manufactured by Mitsubishi Kasei Co., Ltd.), and the dyeing characteristics were measured in the same manner as in Example 1. During the above dyeing, the dye concentration is 0.5% ow
f, the auxiliary agent was 0.5 cc / acetic acid, 120 ° C, and the dyeing condition was 30 minutes.

The film breakage of the sheath nylon was determined by taking a photograph of the surface of the fibers constituting the dyed fabric and enlarging the sheath nylon layer.

The results obtained were as shown in Table 3. Both the fastness to washing and the fastness to light were at practical levels, but the color development was insufficient when the nylon 6 ratio exceeded 75% by weight. Further, when the nylon 6 ratio is less than 20% by weight, it is difficult to uniformly cover the modified polyester of the core portion with a nylon sheath with a sufficient thickness, and there is a phenomenon that the sheath is broken during spinning drawing or knitting finish. It was

When the fabric tension and waist were compared, the sheath nylon ratio was 20.
In the case of up to 75% by weight, it was good, and it was a more preferable feeling as compared with the nylon 6 alone cloth and the polyethylene terephthalate alone cloth.

EFFECTS OF THE INVENTION The dyed conjugate fiber according to the present invention makes it possible to obtain an excellent fiber product having a clear color and excellent light fastness and washing fastness. That is, this dyeing fastness is so excellent that it could not be obtained with a bright color fiber product consisting of polyamide fibers only.

Moreover, since the modified polyester layer is present in the core portion, it is excellent in dimensional stability and wrinkle resistance, and has appropriate tension and elasticity.
In addition, the drawbacks such as the abrasion resistance and the resin processability that are found in the cloth made of the modified polyester fiber are not sufficient.
It is improved by disposing the polyamide layer in the sheath portion, and the color depth is also improved.

Since it has these characteristics, the composite fiber according to the present invention can be suitably used for sportswear, outerwear and the like, which are required to have excellent methods of both vivid color and dyeing fastness.

Claims (2)

[Claims] 1. A core-sheath type composite fiber in which a polyamide is arranged in a sheath portion and a sulfonated aromatic dicarboxylic acid-modified polyester is arranged in a core portion, and substantially only a cationic dye is dyed as a dye. The dyed composite fiber is characterized in that the dye dyeing ratio of the core is 10% or less and the dye dyeing ratio of the core is 0.2% owf or less. 2. The dyed composite fiber according to claim 1, wherein the polyamide sheath has a composite ratio of 20 to 75% by weight.