JP2002138372A - Woven or knitted fabric and method for producing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a woven or knitted fabric showing extremely high color development of black, capable of allowing alkali reduction treatment, and having soft feeling, and further to provide a method for producing the fabric. SOLUTION: The woven or knitted fabric is characterized in that the yarns constituting the woven or knitted fabric consist essentially of a polyester core- sheath conjugate fiber in which the sheath component contains colloidal silica particles mixed therewith, and has minute unevenness formed on the surface of the fiber by an alkali reduction treatment, and the core component is a component originally colored with carbon particles and/or a black organic coloring matter mixed therewith, and the yarn including the sheath component is dyed with a black dispersion dye and/or cationic dye, and the surface of the fiber is finished by a polymer film having a low refractive index.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a woven or knitted fabric having excellent black coloring properties when used for a black formal material or the like (hereinafter, "woven or knitted fabric" is collectively referred to as "woven or knitted fabric"). ) And its manufacturing method.

[0002]

2. Description of the Related Art In recent years, the demand for black formal wear accompanying a ceremonial occasion has increased, and polyester materials having excellent anti-wrinkle properties and wash and wear properties have been widely used.

However, polyester has a problem that the refractive index of the polymer is high and the dye cannot be sufficiently dyed into the fiber due to the dense fiber structure, so that it is difficult to obtain a sufficient black coloration. .

On the other hand, there is a method of increasing the apparent color development by attaching a low-refractive index polyurethane resin or the like called deep color processing, which is finished after black dyeing. In this method, in order to maximize the color developability, a measure is taken to increase the amount of the resin to be adhered, but such a method is such that the resin is peeled off by friction or washing when worn, and partially shines. However, there is a limit that such a method alone is not possible, that is, it is not possible to make so-called thick makeup, and it is necessary to enhance the coloring property from the yarn itself.

On the other hand, in the dyeing of polyester, since the fiber structure is dense, high-pressure and high-temperature dyeing is usually performed at about 130 ° C. to allow the dye to penetrate inside the fiber as much as possible. The color dye could not reach the center of the fiber. In other words, only the surface of the so-called ring dye is dyed, and the center is white without dyeing, so the amount of reflected light increases due to the scattered light from the inside of the fiber, and the color development of black becomes extremely low. I will.

[0006] This is because a dark color dye such as black usually has a high molecular weight (molecular weight: 500 to 700 mol) due to the color fastness.
This is because the dye cannot be used to permeate or diffuse into the fiber.

On the other hand, a method of further increasing the dyeing temperature to, for example, 140 ° C. or higher causes decomposition of the dye and deterioration of the fiber, and cannot be solved. Further, from the viewpoint of the dye, in the method using a low-molecular weight dye for light and medium colors, the degree of internal diffusion of the dye into the fiber is increased, but the black color density is not sufficiently increased, and after the dyeing, iron heat is applied. As a result, the dye easily comes out (bleed-out phenomenon), and there is a problem of poor fastness, so that it cannot be adopted.

On the other hand, there is an original yarn called carbonized yarn, which is obtained by mixing carbon or the like in the fiber. Such a black color develops in a direction to be enhanced. However, in order to obtain a soft texture of a woven or knitted polyester fabric, Prior to dyeing, it is necessary to perform an alkali weight reduction treatment.

[0009] However, in such a treatment, there is a problem that the carbon is eluted into the alkaline solution to contaminate the treatment machine or to other fabrics, so that the alkali reduction treatment cannot be actually performed. In other words, the polyester is hydrolyzed from the fiber surface by the hot alkaline solution, so that carbon in the surface layer of the fiber is dissolved in the alkaline solution simultaneously with the polyester.

[0010] When the alkali weight reduction treatment is not performed, the texture becomes rough and the practicability is extremely poor.

Further, a method is known in which silicon oxide particles such as agglomerated silica are mixed into fibers to form a woven or knitted fabric, and thereafter the surface of the fibers is made uneven by an alkali treatment to suppress light reflection and enhance coloring. Have been. However, in this method, since the particles are coarse, fine irregularities do not appear on the fibers, and the color development of black becomes insufficient. Also, because the particles are large,
There is a problem in that the metal rolls in the yarn production and the material in the weaving are worn away and the rough surface scratches cause fluff and yarn breakage, and the replacement of the metal member is troublesome and inefficient.

[0012]

SUMMARY OF THE INVENTION In view of the problems of the prior art, the present invention provides a woven or knitted fabric having extremely high black color development, capable of performing alkali reduction treatment, and having a soft texture. It is another object of the present invention to provide a method for easily and efficiently producing the woven or knitted fabric.

[0013]

The present invention employs the following means in order to solve the above-mentioned problems.

That is, in the woven or knitted fabric of the present invention, the main component of the yarn constituting the woven or knitted fabric is a polyester core-sheath composite fiber, and colloidal silica particles are mixed in a sheath component of the core-sheath composite fiber; Fine irregularities are formed on the surface of the fiber by the alkali weight reduction treatment, the core component is a soaked component mixed with carbon particles or / and a black organic dye, and the fiber containing the sheath component is a black disperse dye or And / or a composite fiber yarn dyed with a cationic dye, and the fiber surface is finished with a polymer film having a low refractive index.

The method for producing a woven or knitted fabric according to the present invention is characterized in that a polyester homopolymer or / and a cationic dyeable polyester polymer is used, a non-drained component in which colloidal silica particles are mixed in a sheath component, and a core component is used. Using a raw material component in which carbon particles or / and a black organic dye are mixed, a composite yarn is spun into a core-sheath type to form a yarn, which is then formed into a woven or knitted fabric, and then subjected to alkali weight reduction processing. Dyeing with a disperse dye or / and a cationic dye,
A method for producing a woven or knitted fabric, characterized in that the fiber surface is finished with a polymer film having a low refractive index.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION The woven or knitted fabric of the present invention is mainly composed of a polyester core-sheath composite fiber, and the composition ratio of such fibers to the woven or knitted fabric is not particularly limited. In order to obtain the effects of the present invention, it is preferable that the composition be a ratio containing 100 to 30% by weight or more.

Here, as the polyester fiber, polyethylene terephthalate, polypropylene terephthalate, polybutylene terephthalate, polyhexamethylene terephthalate, and the like are preferably used. Most preferred. In addition, in polyethylene terephthalate, besides the usual homopolymer,
Cationic dye dyeable polyester polymers can also be preferably used because they enhance the color developability. In this case, as the polymer, metal sulfonic acid is 1 to
A copolymer obtained by copolymerizing about 8 mol of polyester is preferable because of excellent yarn strength and resistance to alkali weight reduction.

In the present invention, the sheath component of the core-in-sheath composite fiber is a non-dyeing component polyester into which carbon and an organic dye are not mixed, and is an ordinary homopolyester polymer or a cationic dyeable polyester polymer. A dye using a homopolyester polymer is dyed with a disperse dye, and a dyeable polyester polymer with a cationic dye is dyed with a cationic dye. In addition, since the fiber structure of the dyeable type polyester of the cationic dye is relatively relaxed, it can be dyed even with a disperse dye. In any case, each dye can be used alone or in combination.

In the present invention, a polyester polymer mixed with colloidal silica particles is used as the polyester of the sheath component of the core-sheath composite fiber. Since these particles have an extremely small particle size, the size of the fine irregularities (microcraters) of the dissolution trace of the fibers in the alkali weight reduction processing (treatment) can be expressed finely, so that the color developability can be improved. Also,
Since the particle size is small, it is preferable because fluff and yarn breakage do not occur without abrasion of metal rolls in yarn production or sewage in weaving.

The particle size of the colloidal silica is 0.05 to
It is preferably 0.1 μm, and silica particles are added to ethylene glycol or water to form a sol and polymerized.

The mixing amount of the silica particles is not particularly limited.
It is preferable to mix by weight% from the viewpoint of the spinning property and the black coloring property. If the amount is less than 0.3% by weight, the coloring properties may be insufficient. If the amount exceeds 10% by weight, yarn breakage tends to occur at the time of yarn production, and thus care must be taken.

Even if silica particles are mixed in the sheath component, the particles are white, so that there is no liquid contamination such as carbon in the alkali weight reduction treatment, and the weight reduction processing can be performed.

The composite ratio of the sheath component of the composite fiber is preferably 95 to 10% by weight of the entire composite fiber. If it exceeds 95% by weight, the composite ratio of the core component becomes small, and the black color developability is insufficient. If the content is less than 10% by weight, the sheath component layer becomes thin, is easily attacked by alkali, and it is difficult to perform a weight reduction treatment, and at the same time, it becomes difficult to obtain a soft texture. A particularly preferable composite ratio of the sheath component is 90 to 40% by weight.

In the present invention, carbon particles and / or
And a polyester polymer original component mixed with a black organic dye.

Types of carbon particles and black organic dyes,
The components and the like are not limited, but carbon black is preferably used for carbon particles, black pigment is used for black organic pigment, or black soluble dye mainly containing nigrosine is preferably used from the viewpoint of coloring property and heat resistance.

The mixing amount of the soaked component is not limited, but it is preferable to mix it so as to contain 1 to 10% by weight in the ratio of the whole conjugate fiber from the viewpoint of the spinning property and the black coloring property.

A preferred method is to blend a polymer obtained by mixing a small amount of polyamide with carbon into a polyester polymer as a core component, impart conductivity and impart antistatic properties, and at the same time enhance color development.

The composite form (fiber cross-sectional form) of the core-sheath fiber is not particularly limited, but a form having the same shape as the core-sheath is preferable. For example, it is a concentric form having a circular shape or the same form having a triangular core-sheath, and both are preferable composite forms in which the sheath component has a uniform thickness and carbon of the core component is not attacked by alkali reduction treatment.

The yarn form of the present invention is not particularly limited, but filament yarn and spun yarn are preferably used. In particular, in the case of the filament yarn, the multifilament is a preferable form that can be easily formed efficiently, has good entanglement workability and twisting workability, and can diversify a woven or knitted fabric. Spun yarn is preferable because a warm texture can be obtained.

In the multifilament, a semi-drawn yarn (POY) may be used in addition to a normal drawn yarn. POY is preferable because it has good dyeing properties, can be crimped at the yarn processing stage, and can also impart stretchability. The fineness of the fiber is not limited, but is preferably 50 to 400 decitex, and is preferable because it can be made from thin to thick ground.

Next, the core-sheath conjugate fiber is used as it is.
It may be made into a woven or knitted fabric without twist, but strong twist is applied to the yarn, and the amount of light absorption is taken in the gap between twists,
This is a preferable method because the coloring property can be improved. The number of twists is, for example, 800 to 100 dtex.
It is preferable to apply a twist equivalent to 3000 turns / m.

Next, when producing a woven or knitted fabric, the polyester composite fiber of the present invention is mainly used, and a small amount of silica, ordinary polyester fiber or polyamide fiber which is not soaked, It may be made into a woven or knitted fabric by mixing or weaving natural fibers such as cotton and hemp.

As for the structure, the woven fabric is surge (twill),
Amundsen, cashmere skin, double woven fabric, and the like are preferable because they can enhance the color development. For a knitted fabric, from the same effect, sheeting, mock Milan ribs, smooth and the like are preferable.

The greige and knitted fabrics formed into the woven and knitted fabrics are then subjected to a dyeing process, which is usually scoured and set, and then subjected to an alkali weight reduction treatment. The method of reducing the weight is preferably a method of reducing the amount of the liquid flow or the method of reducing the amount of suspension in which the woven or knitted fabric is dipped in hot caustic soda, because the weight can be selectively reduced from the surface of the fiber. The weight loss rate of the polyester due to the weight loss treatment should be determined according to the desired texture, but basically it is possible to reduce the weight loss to the composite rate of the sheath component of the composite fiber. It should be noted that if the amount is reduced beyond the compounding ratio of the sheath component, the carbon of the core component is eluted and must be avoided.

After the weight reduction treatment, dyeing is carried out at normal high pressure and high temperature using a usual black disperse dye and / or cationic dye. The dyeing temperature is 125 based on the color developing property and the decomposability of the dye.
It is preferred to dye at ~ 135 ° C.

For finishing after dyeing, ordinary deep color processing can be applied. However, it is desirable to provide a low refractive resin which has good black color development and does not decrease the color fastness, and has an adhesion amount. As the deep-colored resin, a fluororesin having a refractive index of 1.5 or less or /
And a resin mainly composed of a silicon-based resin is preferable, and it is preferable that the difference in lightness (L value) between before and after the application of the resin is suppressed to about 1 to 2 or less.

Examples of the fluorine resin include tetrafluoroethylene-hexafluoropropylene copolymer, polypentadecafluorooctyl acrylate, polytetrafluoroethylene, polyfluoroethyl acrylate, polytrifluoroethyl acrylate, polytrifluorochloroethylene, Trifluoroisopropyl methacrylate, polytrifluoroethyl methacrylate, or the like can be used, but is not limited thereto.

As the silicone compound, polydimethylsilane, dimethylpolysiloxane, methylhydrogenpolysiloxane, amino-modified silicone, epoxy-modified silicone, polyether-modified silicone, carboxy-modified silicone, and the like can be used. It is not something that can be done.

In the present invention, it is preferable to use these fluorine-based compounds and silicone-based compounds in combination in terms of imparting excellent deep-colored properties. Each of the polymers, monomers, reaction intermediates and the like may be used alone. Or a combination of two or more.

In the present invention, it is preferable that the refractive index of the polymer film is 1.5 or less from the viewpoint of improving deep color. From the viewpoint of color developing properties, those having a refractive index of 1.5 or less, more preferably 1.4 to 1.1 are preferred.

Film processing (deep color processing) of such a resin polymer
Although not particularly limited, the dyed knitted fabric is immersed in a resin solution, and a treatment solution having a squeezing ratio of 50 to 150% by weight is attached by padding. Dried at 150-170 ° C. for 20-6 minutes
A method of forming a film by performing a heat treatment for 0 second is a preferable method that can provide uniform and high resin adhesion durability.

As described above, the woven or knitted fabric thus obtained is a woven or knitted fabric having extremely high black coloring properties, capable of being subjected to alkali weight reduction treatment and having a soft texture, and can be easily and efficiently produced. Could be the way.

[0043]

EXAMPLES The evaluation in the examples was carried out by the following method. (1) Black color development evaluation: SM dyed woven or knitted product
The lightness: L value is determined using a color computer color difference meter (manufactured by Suga Test Instruments Co., Ltd.). The smaller the numerical value, the better the black color development. Usually, if there is a difference of 0.5 or more in L value, there is a dominant difference even when visually observed. (2) Contamination of alkaline solution: In alkali reduction treatment before dyeing, the degree to which the deposited carbon particles are eluted in alkali is evaluated by visual evaluation in three stages.
2nd grade: somewhat, usually 1st grade: liquid contamination, bad. (3) Texture evaluation: The softness of the fabric was evaluated by sensory evaluation by handling. (4) Abrasion of the loom: Observation of the abrasion of the loom when a new loaf is continuously woven for 7 days using a scanning microscope.
The presence or absence of scratches was evaluated. Example 1 (Spinning of core-sheath conjugate fiber) Both the core and sheath are homopolymer polyester components, and 15% by weight of carbon black particles (manufactured by Sanyo Pigment Co., Ltd.) are mixed in the core component (the carbon particles are 3% by weight as a whole conjugate fiber). %), Added to ethylene glycol as a sheath component, and made into a sol. 0.4% by weight of colloidal silica having a particle size of 0.05 μm (μm) (0.32% by weight as a whole composite fiber). And the core:
The mixture was extruded from a die at a ratio of 20% by weight and a sheath: 80% by weight, and composite-spun into a concentric core-sheath shape. This is 3.5
The polyester multifilament was drawn twice, and a polyester multifilament drawn yarn having a core-sheath type round cross section of 84 filaments and 36 filaments was obtained. (Weaving) The fiber is twisted at 2,500 times / m by a twisting machine, and twisted and set under steam at 80 ° C., and used for warp yarn and weft yarn, warp yarn density: 124 / inch, weft yarn Density: woven into a georgette fabric at 84 lines / inch. (Dyeing) Then, the woven fabric is subjected to ordinary scouring (hot water 1).
20 ° C.) and set (dry heat 190 ° C.), and then subjected to alkali reduction treatment with a jet dyeing machine. The treatment conditions were: caustic soda solution: 3.5%, treatment temperature: 100 ° C., treatment time: 65 minutes, and the weight of the woven fabric was reduced to 22%. Subsequently, high-pressure high-temperature dyeing was performed at 130 ° C. for 60 minutes with a black disperse dye using the same dyeing machine. The dye is Dianix Black BG-FS
(Manufactured by Dystar) at a staining density of 14%. Next, the fluororesin “Max Guard EC24”
3 "(manufactured by Keishin Kasei, fluorine-based water repellent, refractive index 1.38)
4% by weight and silicone resin “Toray Silicon SM8”
702 "(manufactured by Toray Silicone Co., Ltd., amine-modified dimethylpolysiloxane, refractive index: 1.48) is padded with a 1% by weight mixed resin, and a processing liquid having a squeezing rate of 100% by weight is attached thereto, and then is subjected to 120 ° C. for 3 minutes. Dry and then at 160 ° C. for 30
Heat treatment was performed for 2 seconds to perform a deep color process for forming a polymer film. Comparative Example 1 Weaving, dyeing, and finishing were carried out in the same manner as in Example 1 except for a multifilament (84 decitex, 36 filament) of a single homopolymer polyester without a core-sheath composite. Comparative Example 2 In the case of a multifilament of the uncoated polyester in which carbon particles not having a core-sheath composite were mixed in the entire fiber (3% by weight of carbon particles mixed in the entire composite fiber, 84 decitex, 36 filaments as in Example 1) About this, other than this, weaving and dyeing processing according to Example 1,
Finished. Comparative Example 3 Polyester-only multifilament in which ordinary aggregated silica particles having no core-sheath composite were mixed in the entire fiber (Example 1)
In the same manner as in the above, the silica particles were mixed at 0.32% by weight as a whole, 84 decitex, and 36 filaments). Comparative Example 4 An uncoated polyester multifilament in which a core is a core-sheath conjugate fiber, in which a silica particle is not mixed in a sheath, and a carbon particle is mixed in a core (similar to Example 1, carbon particles are 3% by weight as a whole conjugate fiber) Other than the above, weaving, dyeing, and finishing were carried out in the same manner as in Example 1 for the case of mixing (84 dtex, 36 filaments). (Evaluation Results) In the present invention (Example 1), the L value is 9.5, the black color developability is extremely high, and there is no liquid contamination in the alkali weight reduction treatment, which is good (grade 3) and soft. An excellent high quality jet-black georgette fabric with a texture was obtained. The dyeing fastnesses such as washing fastness, rubbing fastness, dry cleaning fastness and the like were all of class 4 or higher, and were satisfactory. In addition, no flaws were found in the weaving by weaving with the silica particles, and there was no yarn breakage or fluffing, and the production was simple and efficient.

On the other hand, in Comparative Example 1, the average black color development (L
Value: 11.7), and in Comparative Example 2, the black color developability was L value:
Although it was 11.3, the liquid contamination in the alkali weight reduction treatment was extremely poor (grade 1), and the weight reduction treatment was not practically applicable. In Comparative Example 3, the L value was 10.6.
In Comparative Example 4, the L value was 9.8, and there was a tendency for good coloring properties, but all were inferior to those of the present invention. Incidentally, in Comparative Example 3, scratches on the rubbing during weaving by the silica particles were remarkably observed, and there was a problem that thread breakage and fluffing occurred. Example 2 (Yarning of core-sheath conjugate fiber) Except that a core-sheath conjugate fiber was drawn 1.8 times to obtain a polyester multifilament yarn of 137 decitex and 36 filaments of semi-drawn yarn (POY). The yarn was made in accordance with No. 1. (Weaving) The fiber is temporarily processed into 84 decitex and 36 filaments, twisted and set according to Example 1, and used for warp and weft yarns. Warp yarn density: 120 / inch , Weft yarn density: 80 yarns /
Inch was woven into a vertical double woven fabric. (Dyeing process) This fabric is subjected to ordinary scouring (hot water 110 ° C),
The mixture was set (dry heat 180 ° C.), and then subjected to an alkali reduction treatment with a jet dyeing machine. The treatment conditions were caustic soda solution: 3.5
%, Treatment temperature: 100 ° C., treatment time: 60 minutes, and the weight loss rate of the woven fabric was 26%. Subsequently, high-pressure high-temperature dyeing was performed at 130 ° C. for 60 minutes with a black disperse dye using the same dyeing machine. Dyeing conditions and deep color processing were finished according to Example 1. (Evaluation Results) In the present invention (Example 2), the L value was 8.1, the black color development was extremely high, and there was no liquid contamination in the alkali weight reduction treatment. There was obtained a high-quality vertical double woven fabric having a soft texture. There were no problems with the color fastness and processing passability.

Example 3 (Yarning of core-sheath conjugate fiber) Both the core and sheath are cationic dye dyeable polyester components obtained by copolymerizing 1.8 mol% of 5-sodium sulfoisophthalic acid, and the core component is a black pigment. 0.4% by weight of colloidal silica solubilized by adding 10% by weight of particles (pigment particles: 3.3% by weight as a whole composite fiber) to the polyester-laden molten polymer and the sheath component and water 0.28% by weight as a whole composite fiber
The mixed polymer was extruded from a die at a ratio of core: 30% by weight and sheath: 70% by weight, and composite-spun into a core-sheath shape having a triangular cross section. This was stretched 3 to 8 times to obtain a core-sheath type cationic dyeable polyester multifilament trifilament triangular cross-section yarn having 55 decitex and 24 filaments. (Knitting) The fiber is twisted at 1000 times / m with a twisting machine,
Set at 20 ° C under steam and well yarn density: 42
The knitted fabric was knitted at an average density of 40 pieces / inch. (Dyeing process) The knitted fabric is subjected to ordinary scouring (hot water 120 ° C),
The mixture was set (dry heat 190 ° C.), and then subjected to alkali reduction treatment with a jet dyeing machine. The treatment conditions were caustic soda solution: 1.5
%, Treatment temperature: 100 ° C., treatment time: 55 minutes, and the weight loss rate of the fabric was 26%. Subsequently, high-pressure high-temperature dyeing was performed at 130 ° C. for 60 minutes with a black cationic dye using the same dyeing machine.
The dye was stained with Cachilon Black CDFH (manufactured by Hodogaya Chemical Co., Ltd.) at a staining density of 8%. Next, deep-color processing was performed with the fluorine-based / silicon-based mixed resin of Example 1 to finish. Comparative Example 5 In the case of a cation-dyeable polyester single multifilament (55 filaments, 24 filaments) having no core-sheath composite, knitting, dyeing and finishing were carried out in the same manner as in Example 3 except for this. (Evaluation result) In the present invention (Example 3), the L value is 8.2, the black color developability is extremely high, and there is no liquid contamination in the alkali weight reduction treatment, which is good (grade 3), silky An excellent sheet of knitted fabric having a glossy and soft texture was obtained. In addition, it could be manufactured efficiently without any problems such as process passability. On the other hand, in Comparative Example 5, the L value was 11.5, and the color was mediocre black.

[0046]

According to the present invention, it is possible to provide a woven or knitted fabric having extremely high black color development, capable of performing alkali weight reduction treatment, and having a soft texture, and a method for easily and efficiently producing the same.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) D06M 11/38 D06M 15/256 4L048 15/256 15/277 15/277 D06P 3/52 F D06P 3/52 3/54 Z 3/54 5/08 Z 5/08 D06M 101: 32 // D06M 101: 32 5/02 D D01F 8/14 A F term (reference) 4H057 AA01 AA02 BA03 BA08 CA37 CB08 CC03 DA01 DA17 DA30 EA01 4L002 AA07 AB00 AB02 AB05 BA01 DA03 DA04 DA05 FA01 4L031 AA18 AB10 AB32 AB33 BA11 CA01 DA09 4L033 AA07 AB02 AB05 AB06 AC15 CA17 CA22 CA59 CA70 DA07 4L041 AA07 BA02 BA05 BA24 BA57 BC08 CA06 CB02 A28 AB28 AB25 DD07 BA01 BA02 BA10 CA00 CA04 CA12 CA15 EB00 EB04 EB05

Claims (4)

[Claims] 1. A yarn comprising a woven or knitted fabric is mainly composed of a polyester core-sheath composite fiber, and colloidal silica particles are mixed in a sheath component of the core-sheath composite fiber, and the fiber surface is treated by alkali reduction treatment. Fine irregularities are formed, the core component is an original component mixed with carbon particles or / and a black organic dye, and the fiber containing the sheath component is dyed with a black disperse dye or / and a cationic dye. A woven or knitted fabric comprising a composite fiber yarn, wherein the fiber surface is finished with a polymer film having a low refractive index. 2. The composite fiber, wherein the sheath component is composited at a ratio of 95 to 10% by weight, and the colloidal silica particles are contained at a ratio of 0.3 to 10% by weight.
2. The woven or knitted fabric according to claim 1, wherein 10% by weight is mixed. 3. The fiber surface is coated with a polymer mainly composed of a fluorine resin and / or a silicon resin having a refractive index of 1.5 or less.
The woven or knitted fabric described. 4. A polyester homopolymer and / or a cationic dye-dyed polyester polymer, a non-drained component containing colloidal silica particles mixed in a sheath component, and carbon particles and / or a black organic dye mixed in a core component. Using the obtained original component, composite spinning into a core-sheath type is formed into a yarn, which is formed into a woven or knitted fabric, then subjected to alkali weight reduction processing, and dyed with a black disperse dye or / and a cationic dye, Next, a method for producing a woven or knitted fabric, wherein the fiber surface is finished with a polymer film having a low refractive index.