JP2015166501A - Method for producing false-twist textured yarn for black formal clothing and fabric - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for producing a false-twist textured yarn for black formal clothing capable of imparting aesthetic properties such as black color development, deep colorability, texture and drape properties, as well as an excellent and long-lasting heat insulation effect regardless of weather and indoor or outdoor to a fabric and to provide a fabric including a textured yarn produced by the method.SOLUTION: There is provided a method for producing a false-twist textured yarn that is composed of polyester filaments containing far-infrared radioactive fine particles and exothermic fine particles. The method for producing a false-twist textured yarn for black formal clothing includes: heat treating a polyester highly-oriented undrawn yarn without drawing; and then simultaneously drawing and false twisting the heat treated polyester highly-oriented undrawn yarn. There is also provided a fabric obtained by using the false-twist textured yarn.

Description

  The present invention relates to a method for producing a false twisted yarn for black formal clothing that exhibits an excellent heat retaining effect when made into a fabric, and a fabric using a false twisted yarn produced by the method.

  Polyester filament yarns are excellent in physical and chemical properties, and are used as an easy care material in many clothing products.

  Among the garments, there are garments worn during ceremonies and black formal garments. As a material used, for men, mainly wool or a wool blend material is used, and for ladies, a polyester material excellent in aesthetics is mainly used.

  Among them, polyester materials that can sufficiently develop black color developability and deep colorability when made into fabrics are preferred for black formal clothing. For example, after fiberizing a polymer containing fine silica, this is alkali-treated to roughen the fiber surface, or by providing voids between the fibers by thread processing, etc. to suppress light dissipation and deep color There have been proposed methods of giving In addition, a method has also been proposed in which a fluorine-based resin, a silicon-based resin, or the like is applied to the fiber fabric surface to develop deep color properties.

  Also, black formal garments are usually not often layered from the point of use. Therefore, when wearing black formal garments outdoors in winter, it is required to have heat retaining properties and a function to adjust warmth. In addition to indoors, for example, in a funeral hall, the room temperature is adjusted to be low for a specific reason. Therefore, as in the case of outdoor use, the clothing is required to have a heat retaining property and a temperature adjustment function.

  Many methods have been proposed so far to impart heat retention to fabrics. For example, a method using a dead air layer or a hygroscopic heat generation function, a method using an absorption heat conversion effect for converting sunlight into heat, and the like have been proposed.

  However, the method of achieving heat retention using the dead air layer is merely a passive method of suppressing heat dissipation using air accumulated in clothes, so it lacks sustainability and has sufficient heat retention. Cannot be expected. In addition, the use of the moisture absorption heat generation function is a technique to obtain heat retention by using a fiber that generates heat by absorbing moisture at the time of sweating, and when it absorbs moisture, it generates heat but lacks sustainability. There is a problem of heat dissipation immediately. In addition, when used for the absorption heat conversion effect, a sufficient heat-retaining effect is observed outdoors in fine weather due to the positive heat generation. However, there is a problem that the effect can hardly be expected in rainy weather or indoors where the amount of sunlight is small.

  In recent years, besides the above method, a method using far infrared rays has been proposed. Specifically, by receiving electromagnetic waves in the far-infrared region, cellular tissues inside the body resonate and vibrate, thereby promoting blood circulation and obtaining a heat retaining effect. For example, Patent Document 1 describes a far-infrared radioactive composite fiber containing far-infrared radioactive fine particles. However, there is a limit to the amount of far-infrared radiation emitted from the fiber, and there is a problem that a sufficient heat retention effect cannot be obtained.

Japanese Patent Laid-Open No. 9-59827

  As described above, there has been proposed a technique for sufficiently improving the black color developability and deep colorability to obtain desired aesthetics when used as a fabric, and at the same time, exhibiting an excellent heat retention effect indoors and outdoors. Not. Of course, there is no example of applying the yarn that can give such characteristics to the fabric and the fabric using the yarn to the black formal garment.

  The present invention eliminates the disadvantages of the prior art, and has an excellent heat retention effect that is durable regardless of the weather or other indoors and outdoors, as well as aesthetics such as black color development, deep color, texture and drape. It is a technical problem to provide a method for producing a false twisted yarn for black formal clothing that can be applied to a fabric, and a fabric using the processed yarn produced by the method.

  As a result of intensive studies to solve the above-mentioned problems, the present inventor has performed a predetermined aesthetic treatment on a fabric by false twisting a polyester highly oriented unstretched yarn containing infrared radiation fine particles and exothermic fine particles by a specific method. As a result, it was found that a processed yarn capable of imparting good properties and excellent heat retaining properties was obtained, and the present invention was made.

  That is, this invention makes the following a summary.

(1) A method for producing a false twisted yarn comprising polyester filaments containing far-infrared radioactive fine particles and exothermic fine particles, wherein the polyester highly oriented unstretched yarn is heat-treated without being stretched and then simultaneously stretched. A method for producing false twisted yarn for black formal clothing, characterized by twisting.
(2) The cross section of the polyester filament has a core-sheath structure, the far infrared radiation fine particles are contained in a sheath component, and the content of the far infrared radiation fine particles is 0.1-2. The false twisting process for black formal clothing according to (1), wherein the mass ratio of the core-sheath in the filament (core component / sheath component) is in the range of 95/5 to 15/85. Yarn manufacturing method.
(3) 0.1 to 2.5 parts by mass of the exothermic fine particles are contained in 100 parts by mass of the sheath component of the polyester filament. Yarn manufacturing method.
(4) A fabric using the false twisted yarn for black formal clothing obtained by the method according to any one of (1) to (3), wherein the L * value is 16 or less. Fabric.

  According to the production method of the present invention, it is possible to provide a false twisted yarn for black formal clothing that can impart excellent heat retention in addition to aesthetic properties such as black color developability, deep color, texture, and drape on the fabric. . The fabric using the processed yarn according to the present invention is suitable for black formal clothing for autumn and winter.

Hereinafter, the present invention will be described in detail.
In the production method of the present invention, a polyester highly oriented undrawn yarn is drawn and false-twisted by a specific method. The filament (single yarn) constituting the polyester highly oriented undrawn yarn contains far-infrared radiation fine particles and exothermic fine particles.

The polyester highly oriented unstretched yarn in the present invention may be any one composed of polyester represented by polyalkylene terephthalate. Specific examples include polyethylene terephthalate (PET), polybutylene terephthalate, and polytrimethylene terephthalate. In view of viscosity, thermal characteristics, compatibility, etc., aromatic dicarboxylic acids such as isophthalic acid and 5-sulfoisophthalic acid, and aliphatic dicarboxylic acids such as adipic acid, succinic acid, suberic acid, sebacic acid and dodecanedioic acid. Acids and aliphatic diols such as ethylene glycol, propylene glycol, 1,4-butanediol, 1,4-cyclohexanedimethanol, glycolic acid, hydroxybutyric acid, hydroxyvaleric acid, hydroxycaproic acid, hydroxypentanoic acid, hydroxyheptane Acids, hydroxycarboxylic acids such as hydroxyoctanoic acid, and aliphatic lactones such as ε-caprolactone may be copolymerized.
Examples of far-infrared radiation fine particles include minerals such as mica and calcite, oxide ceramics such as tin oxide, alumina and silicon dioxide, carbide ceramics such as silicon carbide and boron carbide, and metals such as platinum and tungsten. . In particular, from the viewpoint of suppressing guide wear during false twisting, a material having low hardness such as mica is preferable.

  Any exothermic fine particles can be used as long as they absorb electromagnetic waves such as sunlight and generate heat. Specifically, zirconium carbide or carbon is preferable.

  The structure of the filament constituting the polyester highly oriented undrawn yarn is not particularly limited, but from the viewpoint of heat retention, it has a core-sheath structure, and far infrared radiation fine particles are contained in a predetermined amount in the sheath component. Those are preferred. This is because by disposing far-infrared radiation fine particles in the sheath component, the distance between the fine particles and the human body can be shortened, and as a result, far-infrared rays easily reach the human body.

  In the present invention, the exothermic fine particles are also preferably contained in the filament sheath component. This is because the sheath component, that is, the outside of the filament is more susceptible to light. Further, in the present invention, the heat generated by the exothermic fine particles can be used not only to give warmth to clothes or the human body, but also to increase the temperature of the far-infrared radioactive fine particles themselves. Since many far-infrared rays are emitted as the temperature rises, an excellent heat retention effect is achieved as a result. In particular, when both the fine particles are arranged in the filament sheath component for the above reasons, both the fine particles are close to each other in the sheath component. This is more efficient.

Although it does not specifically limit as content of a far-infrared radiation fine particle and an exothermic fine particle, Usually, it is preferable that it is 0.1-10 mass parts with respect to 100 mass parts of filaments, respectively.
Since the cost and spinning operability of the highly oriented undrawn yarn generally tend to deteriorate as the content of fine particles increases, it can be said that the smaller the content of fine particles, the better. In this respect, in the present invention, by using the far-infrared radioactive fine particles and the exothermic fine particles in combination, the heat generated by the exothermic fine particles is used to increase the temperature of the far-infrared radioactive fine particles, thereby promoting the far-infrared radiation effect. Thus, a certain level of far-infrared radiation effect can be secured even if the content of both fine particles is somewhat reduced. That is, in the present invention, a sufficient heat retaining effect can be secured even if the contents of both fine particles are slightly reduced in consideration of the cost of the highly oriented undrawn yarn and the spinning operability.

  In the present invention, it is preferable that both fine particles are contained in the filament sheath component in order to obtain an excellent far-infrared radiation effect. In this case, the content of both fine particles is preferably 0.1 to 2.5 parts by mass with respect to 100 parts by mass of the sheath component. When the content of at least one of both fine particles is less than 0.1 parts by mass, the desired synergistic effect tends not to be exhibited. On the other hand, if the content of at least one of both fine particles exceeds 2.5 parts by mass, the spinning operability tends to deteriorate.

  Moreover, when the cross section of the filament has a core-sheath structure and both fine particles are included in the sheath component, the mass ratio of the core-sheath is preferably in the range of 95/5 to 15/85, and is 85/15 to 40/60. A range is more preferred. When the mass ratio of the core sheath satisfies this range, both fine particles are arranged in an appropriate amount to the sheath component, which is advantageous for obtaining a predetermined heat retaining effect, and thus spinning operability is also stabilized.

  In the production method of the present invention, first, a highly oriented undrawn yarn composed of a polyester filament containing the above-described far-infrared radioactive fine particles and exothermic fine particles is prepared. Next, this highly oriented undrawn yarn is heat treated without drawing. By this heat treatment, only the degree of crystallinity of the filament is improved, and the degree of orientation is not improved, but rather decreases. When the degree of crystallinity is improved, the filament is less likely to be thermally deformed at the time of the simultaneous drawing and simultaneous twisting as the next step. By suppressing deformation and flattening of the filament cross section, a fabric with less gloss can be obtained, and as a result, desired deep color properties can be obtained. Further, when the degree of orientation is lowered, the amorphous region where the disperse dye is exhausted and dyed in the filament increases, and the disperse dye can be exhausted more in the filament. Thereby, the coloring property suitable for black formal clothing is obtained.

  Compared with the normal false twist which does not extend | stretch, the extending | stretching simultaneous false twist applies a big tension | tensile_strength to a thread | yarn in a twisting zone by the part which extends | stretches. For this reason, the cross section of the filament is easily flattened, and thus gloss is easily generated when it is made into a fabric. Furthermore, in normal stretching simultaneous false twisting, it passes through the false twist heater in a state where a large tension is applied, so that the degree of crystallinity and orientation of the filament easily advances, and as a result, it becomes difficult to exhaust the dye and the desired deep color. I can't get sex. It is possible to obtain color development and deep color suitable for black formal clothing by exhausting a large amount of disperse dye inside the filament and reducing the gloss of the fabric. Can not do it. The heat treatment in the present invention is performed for such a purpose.

  In the present invention, the highly oriented undrawn yarn that has been heat-treated without being drawn may be wound once, and then introduced into a false twisting machine to simultaneously draw the drawn false twist, but usually considering the cost, yarn quality, etc. It is preferable to introduce the highly oriented undrawn yarn into a false twisting machine equipped with a heat treatment apparatus, and continuously false twist after the heat treatment without winding the yarn. In this case, a special heat treatment apparatus is not required, and usually heat treatment may be performed using a heater provided with a false twister. As the heater of the false twisting machine, a non-contact type heater is preferable. Further, the false twisting machine is not particularly limited, but normally, a pin type low speed false twisting machine, a disk type high speed false twisting machine or the like can be used.

  The temperature at the time of the heat treatment is not particularly limited as long as the finally obtained processed yarn is a temperature at which color development and deep color suitable for black formal garments can be developed when made into a fabric. Specifically, a range of 170 ° C. to 230 ° C. is preferable, and in addition to this, it is more preferable that the temperature is higher by 10 ° C. than the false twisting temperature. The heat treatment is preferably performed with overfeed applied, and the overfeed rate at this time is preferably in the range of 0.5 to 50%.

  After heat-treating the highly oriented undrawn yarn without drawing, the drawing is simultaneously false twisted. Thereby, the target false twisted yarn can be obtained. The draw ratio may be appropriately set in consideration of the physical properties of the processed yarn to be obtained, and is not particularly limited, but is usually 1.2 to 1.6 times in consideration of yarn breakage, poor drawing, etc. The range of is preferable. Furthermore, the false twist temperature (false twist heater temperature) is not particularly limited as long as the twist strain imparted by false twist can be fixed. Usually, the temperature at which the shape can be fixed while suppressing fusion between filaments. May be appropriately selected. Specifically, 160 ° C to 230 ° C is preferable.

  The total fineness of the false twisted yarn obtained according to the present invention can be appropriately selected according to the purpose and performance, but is usually preferably 10 to 440 dtex in consideration of fabric texture, deep color, and the like. 30 to 330 dtex is more preferable, and 50 to 200 dtex is more preferable. The single yarn fineness of the processed yarn is preferably 0.01 to 10 dtex, more preferably 0.1 to 10 dtex, and still more preferably 0.1 to 3 dtex.

  After obtaining the false twisted yarn, the fabric of the present invention can be obtained by producing a raw machine and dyeing the raw machine. The structure of the fabric is not particularly limited. For example, plain weaving, oblique weaving, satin weaving, and multiple weaving can be used for woven fabrics. Circular knitting or half knitting such as flat knitting, pearl knitting, rib knitting, interlock knitting, denby, etc. Warp knitting organizations such as knitting and atlas knitting can be adopted. As for the organization, an appropriate one may be selected in consideration of various physical properties, fastness, and washability in addition to the deep color.

  The fabric may contain yarns other than the processed yarn as long as the effects of the present invention are not impaired. Any thread other than the processed thread can be used. Usually, it is preferable that the above-mentioned processed yarn is contained in a fabric in a proportion of 20 to 100% by mass. If it is less than 20 mass%, it tends to be difficult to obtain the effects of the present invention.

  In the present invention, the properties of the false twisted yarn are adjusted in advance so that the cloth develops color development, deep color and texture suitable for black formal clothing. Good. When trying to realize a deep color using a black dye, the conventional method needs to use about 10 to 12% omf of the dye, and there is a problem that the color fastness is slightly lacking. In the invention, it is possible to expect sufficient color developability and deep color even if it is less than 10% omf, more preferably 7% omf or more and less than 10% omf, and the amount of dye used can be suppressed, so that the color fastness is naturally maintained. it can.

  In the fabric of the present invention, the L * value representing lightness is preferably 16 or less. If it exceeds 16, even if it can be finished into clothes without any particular problem, it will be difficult to apply to black formal use. Smaller lightness is preferable in terms of color developability and deep color.

  In the present invention, after dyeing, dark dyeing may be performed for the purpose of further reducing the brightness. A known method can be adopted as the deep dyeing process. Usually, if a fluorine-based resin, a silicon-based resin, or the like is added, deep color properties can be expressed more. By further deep dyeing after dyeing, the L * value of the fabric can be lowered to about 12 or less.

  EXAMPLES Hereinafter, although an Example and a comparative example are given and this invention is demonstrated in detail, this invention is not limited to these.

  Each measuring method and evaluation method are as follows.

(1) Far-infrared radiation effect The far-infrared radiation intensity | strength of the fabric obtained by each Example and the comparative example was measured. The measurement was performed using an infrared spectrophotometer FT-IR apparatus (“Spectrum GX FT-IR (trade name)” manufactured by PerkinElmer) at a measurement temperature of 40 ° C. and a measurement wavelength range of 5 to 20 μm. At that time, the far-infrared radiant intensity of the black body under the same conditions is also measured, and the ratio (%) of the radiant intensity of each fabric when the radiant intensity of the black body at each wavelength is defined as 100% is calculated at each wavelength. The average value of the ratio was calculated as the average emissivity (%).

(2) Heat generation characteristics In a room maintained at a temperature of 20 ° C. and humidity of 65%, the fabric surface was irradiated with light with an illuminance of 10000 LUX from a reflex lamp, and the back surface temperature was thermographed every hour ("Thermo Tracer" manufactured by NEC Sanei Co., Ltd.). TH7102MX (trade name) ") and evaluated at the highest temperature reached.

(3) Lightness (L * value)
The L * value was measured by a method according to JIS Z8729 and expressed in L * a * b * display system.

Example 1
A resin composition in which 98 parts by mass of polyethylene terephthalate is kneaded with 1.0 part by mass of mica having an average particle size of 3 μm as far-infrared radiation fine particles and 1.0 part by mass of zirconium carbide with an average particle size of 1.5 μm as exothermic fine particles. And a resin made of polyethylene terephthalate were prepared. Then, both are introduced into a compound spinning machine, and the former is used as the sheath component and the latter is used as the core component, and the composite spinning is performed so that the mass ratio between the two (core component / sheath component) is 80/20. A highly oriented undrawn yarn of .7 dtex 24f was obtained. The spinning operability was good.

  Next, the highly oriented undrawn yarn was introduced into a false twisting machine (“LS-6 (trade name)” manufactured by Mitsubishi Heavy Industries, Ltd.) equipped with a heater for heat treatment. First, the temperature was 180 ° C. and the overfeed rate was 2 Heat treatment was performed at a condition of 5%. And without drawing up, the draw ratio is 1.515 times, the number of false twists is 4236 T / M, the false twist direction is Z, the false twist heater temperature is 170 ° C., and the false twist is 62.0 dtex24f. I got a thread.

  Then, using a double twister, the false twisted yarn was twisted at a twist number of 2500 T / M in the S direction and 2500 T / M in the Z direction, and after twisting, vacuum setting was performed at 75 ° C. for 45 minutes. Then, after warping a beam in which yarns twisted in the S direction and yarns twisted in the Z direction are arranged in a ratio of 2: 2, the yarn twisted in each of the above directions as a weft is driven repeatedly 2: 2, I got the life of a heavy tissue. The raw machine density was 145 warps / inch and 130 wefts / inch.

  Next, after scouring and pre-setting the raw machine, dyeing was performed at 130 ° C. for 30 minutes using 8% omf of a black disperse dye “Dianix Black GS-E (trade name)” manufactured by Dystar Japan Co., Ltd. did. After dyeing, a fabric was obtained by final setting.

(Example 2)
A resin composition in which 98 parts by mass of polyethylene terephthalate is kneaded with 1.0 part by mass of mica having an average particle diameter of 3 μm as far-infrared radiation fine particles and 1.0 part by mass of carbon having an average particle diameter of 1.5 μm as exothermic fine particles. And a resin made of polyethylene terephthalate were prepared. Then, both are introduced into a compound spinning machine, and the former is placed in the sheath component and the latter is placed in the core component, and the composite is spun so that the mass ratio between the two (core component / sheath component) is 80/20. A highly oriented undrawn yarn of .7 dtex 36f was obtained. The spinning operability was good.

  Next, the highly oriented undrawn yarn was introduced into a false twisting machine (“LS-6 (trade name)” manufactured by Mitsubishi Heavy Industries, Ltd.) equipped with a heater for heat treatment. First, the temperature was 180 ° C. and the overfeed rate was 2 Heat treatment was performed under the condition of 0.0%. And without winding, it is continuously false twisted under the conditions of draw ratio 1.38 times, false twist number 2750 T / M, false twist direction Z, false twist heater temperature 170 ° C., and false twisting of 132.0 dtex 36f I got a thread.

  Thereafter, using a double twister, the false twisted yarn was twisted in the Z direction at a twist number of 1800 T / M, and after twisting, vacuum setting was performed at 70 ° C. for 45 minutes. And after knitting the raw material of the mock-rod organization with a 28G knitting machine, scouring and pre-setting, and using 8% omf of the black disperse dye “Dianix Black GS-E (trade name)” manufactured by Daistar Japan And it dye | stained on 130 degreeC and the conditions for 30 minutes. After dyeing, a fabric was obtained by final setting.

(Example 3)
Except for changing the content of polyethylene terephthalate to 96 parts by mass, the content of mica to 3.0 parts by mass and the content of carbon to 3.0 parts by mass, respectively, the same procedure as in Example 2 was performed, and highly oriented unstretched Yarn, false twisted yarn and fabric were obtained. The spinning operability was slightly inferior to that in Example 2. The fineness of the highly oriented undrawn yarn was 181.4 dtex36f, and the fineness of the false twisted yarn was 134.0 dtex36f.

Example 4
High orientation is carried out in the same manner as in Example 2 except that the content of polyethylene terephthalate is changed to 99.9 parts by mass, the content of mica is changed to 0.05 parts by mass, and the content of carbon is changed to 0.05 parts by mass. Undrawn yarn, false twisted yarn and fabric were obtained. The spinning operability was good. The fineness of the highly oriented undrawn yarn was 180.4 dtex36f, and the fineness of the false twisted yarn was 133.2 dtex36f.

(Comparative Example 1)
A false twisted yarn and a fabric were obtained in the same manner as in Example 2 except that the heat treatment before the simultaneous simultaneous false twisting was omitted and the draw ratio was changed to 1.42. The fineness of the false twisted yarn was 126.6 dtex36f.

(Comparative Example 2)
The false twisted yarn was carried out in the same manner as in Example 2 except that the overfeed rate during heat treatment was changed to -1.8%, and the draw ratio during simultaneous drawing was changed to 1.36 times. And a fabric was obtained. The fineness of the false twisted yarn was 127.8 dtex36f.

(Comparative Example 3)
Except for the content of polyethylene terephthalate being 100 parts by mass and omitting mica and carbon, the same procedure as in Example 2 was carried out to obtain a highly oriented undrawn yarn, false twisted yarn and fabric. The spinning operability was good. The fineness of the highly oriented undrawn yarn was 182.0 dtex36f, and the fineness of the false twisted yarn was 131.9 dtex36f.

(Examples 5-8, Comparative Examples 4-6)
Using the treatment liquid having the composition shown in the following prescription 1, the fabrics in Examples 1 to 4 and Comparative Examples 1 to 3 were deep-dyed. The deep dyeing process was performed by a padding method under the conditions of a drawing ratio of 60%, drying at 130 ° C. for 5 minutes, and heat treatment at 180 ° C. for 30 seconds. Experimental examples for the fabrics of Examples 1 to 4 and Comparative Examples 1 to 3 were sequentially designated as Examples 5 to 8 and Comparative Examples 4 to 6, respectively.

Formula 1
Vasotex FS-370E (manufactured by Meisei Chemical Industry Co., Ltd., fluorine-based thickening agent) 40 g / L
Pararesin BYS (Ohara Palladium Chemical Co., Ltd., silicon-based thickening agent) 10g / L
Delectol MAP (manufactured by Meisei Chemical Industry Co., Ltd., antistatic agent) 15g / L
Textport SN-10 (manufactured by Nikka Chemical Co., Ltd., penetrant) 2 g / L

  The evaluation results of the knitted fabric obtained above are shown in Table 1.

  The fabrics according to the examples all had a long-lasting heat retaining effect that was not affected by the weather. Further, it was proved that the brightness was low and the black color development and deep color were excellent. It was also confirmed that when the fabric was deep-dyed, the brightness was further lowered and it was easier to apply to black formal applications. The dyeing fastness was also good.

On the other hand, if the heat treatment is omitted before the simultaneous simultaneous false twisting (Comparative Example 1) or if the film is stretched even after the heat treatment (Comparative Example 2), the brightness increases, and the desired color developability and deep color are obtained. It was confirmed that it could not be obtained. Furthermore, if the use of far-infrared radioactive fine particles and exothermic fine particles was omitted, it was also confirmed that the heat retaining effect was not achieved (Comparative Example 3).

Claims (4)

A process for producing false twisted yarn composed of polyester filaments containing far-infrared emitting fine particles and exothermic fine particles, and heat-treating a polyester highly oriented undrawn yarn without drawing, and simultaneously drawing and false twisting simultaneously A process for producing false twisted yarn for black formal clothing. The cross section of the polyester filament has a core-sheath structure, the far-infrared radioactive fine particles are included in the sheath component, and the content of the far-infrared radioactive fine particles is 0.1 to 2.5 parts by mass with respect to 100 parts by mass of the sheath component. The mass ratio of the core-sheath in the filament (core component / sheath component) is in the range of 95/5 to 15/85, The production of false twisted yarn for black formal clothing according to claim 1 Method. The production of false twisted yarn for black formal clothing according to claim 2, wherein the exothermic fine particles are contained in an amount of 0.1 to 2.5 parts by mass with respect to 100 parts by mass of the sheath component of the polyester filament. Method. A fabric using the false twisted yarn for black formal clothing obtained by the method according to any one of claims 1 to 3, wherein the L * value is 16 or less.