JP2018048421A - Deep-dyeable polyester woven or knitted fabric and method for producing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a deep-dyeable polyester woven or knitted fabric that is remarkably excellent in deep-dyeable properties.SOLUTION: The deep-dyeable polyester woven or knitted fabric comprises a deep-dyeable polyester fiber. The deep-dyeable polyester fiber is imparted with real twists by a twist coefficient K of 3,000-30,000. The deep-dyeable polyester fiber has fine pores on a surface of a single fiber. The single fiber of the deep-dyeable polyester fiber is a modified cross-section fiber having a surface on which protrusions and grooves are alternately and approximately uniformly arranged.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a polyester woven or knitted fabric excellent in deep dyeing and a method for producing the same.

  In woven and knitted fabrics made of polyester fibers, various methods have been studied for improving the deep dyeability or the color developability when dyed. In particular, in order to improve the deep dyeing property of the polyester knitted fabric for black formal, methods in various stages such as a filament, a woven or knitted structure, or post-processing are being studied. In particular, with respect to filaments, studies have been made on polymer modification in the spinning process or filament cross-sectional shape.

  For example, it has been studied to improve the deep dyeability by using a polyester fiber having an irregular cross section or fine pores. For example, Patent Document 1 describes a modified cross-section polyester filament having four or more substantially triangular grooves and excellent in color development. The width of the groove is 1 μm or more, the depth is 2.2 μm or more, and the depth of the groove with respect to the width of the groove is 0.8 or more and 2.5 or less.

  Patent Document 2 describes a highly color-forming polyester fiber obtained by blending 5% by weight or more and 30% by weight or less of polypropylene terephthalate in polyethylene terephthalate. On the surface of the polyester fiber, 20 or more streak-like grooves having a width of 0.5 μm or more with respect to the fiber axis direction are arranged.

Further, Patent Document 3 proposes a method for producing a high color developing silky fabric having an L * value of 12 or less. Specifically, the latent crimpable composite polyester multifilament yarn having a crimp rate of 50% or more after the boiling water shrinkage, the birefringence of 70 × 10 ^{−3 to} 120 × 10 ⁻³ , and the boiling water shrinkage rate Less than 5%, weaving blended entangled yarns with deformed composite polyester multifilament yarns that have irregular shapes due to alkali weight loss, using warp and weft yarns, then dyeing finish processing including alkali weight loss treatment Has been given. In Patent Documents 1 to 3 described above, a woven or knitted fabric that achieves a certain level of deep dyeability can be obtained.

Patent No. 2998202 JP-A-11-189971 JP 2000-1119933

  However, in Patent Document 1, the width of the groove is not described, and when the width of the groove becomes too wide, glare occurs due to reflection of incident light, resulting in a deep hue or sufficient dark dyeing. Sex cannot be achieved. Moreover, in patent document 2, it does not describe about the shape of a groove | channel, etc., and it is difficult to achieve deep dyeing like patent document 1. FIG. In addition, since polypropylene is used as the fiber material, it is necessary to perform low-temperature processing in the processing step, so that the dyeing stability of the polyester is poor. Furthermore, in Patent Document 3, a multifilament yarn and a concavo-convex deformed multifilament yarn are used to achieve deep dyeing by using two types of mixed entangled yarns having different crimping rates. It is not possible to achieve sufficient darkness with only crimping.

  It is a technical object of the present invention to provide a polyester woven or knitted fabric that eliminates the drawbacks of the conventional woven or knitted fabric as described above, and that is remarkably excellent in deep dyeability.

  As a result of intensive studies, the present inventors have reached the present invention. That is, the gist of the present invention is the following (1) to (5).

(1) A deeply dyeable polyester woven or knitted fabric containing a deeply dyeable polyester fiber, wherein the deeply dyeable polyester fiber is actually twisted with a twist coefficient K determined by the following formula (I) of 3,000 to 30,000. Is given,
K = T × D ^1/2 (I)
(However, K: Twisting coefficient, T: Twisting times (times / m), D: Fineness (dtex))
The deep dyeable polyester fiber has fine pores on the surface of a single fiber,
The number of the micropores is 10 or more in a 5 μm × 5 μm size region on the fiber surface, the major axis of the micropore is 0.9 μm or less, the minor axis is 0.6 μm or less, and the depth is 100 to 100 μm. 400 nm,
The single fiber of the dark-dyeing polyester fiber is a modified cross-section fiber in which protrusions and grooves are alternately and substantially uniformly arranged on the surface, and the protrusions and the grooves have a rectangular or substantially cross-sectional shape. It has a shape and is continuous in the fiber axis direction.
A deep dyeable polyester woven or knitted fabric characterized in that the number and dimensions of the protrusions simultaneously satisfy the following formulas (II) to (IV):
10 ≦ N ≦ 32 (II)
0.3 ≦ W ≦ 3.0 (III)
0.5W ≦ H ≦ 3.0W (IV)
(Where N is the number of protrusions, W is the width of the protrusion (μm), and H is the height of the protrusion (μm))
(2) The deeply dyeable polyester woven or knitted fabric according to (1), wherein a film containing at least one kind of resin of the group consisting of polyurethane resin, fluorine resin and silicon resin is laminated on the surface. .
(3) The deep dyeable polyester woven or knitted fabric according to (1) or (2), wherein the L value when black dyeing is performed is 12 or less.
(4) A method for producing the deep-dyed polyester woven or knitted fabric according to any one of (1) to (3), comprising the following steps (V) to (VIII):
(V) a step of preparing a latent highly dyeable core-sheath composite polyester fiber in which a hardly soluble polyester resin composition is disposed in the core and an easily soluble polyester resin is disposed in the sheath;
The hardly soluble polyester resin composition includes a hardly soluble polyester resin and generated particles having an average particle diameter of 0.05 to 0.5 μm,
The generated particles are derived from a phosphorus compound and an alkaline earth metal compound, or derived from a phosphorus compound, an alkali metal compound, and an alkaline earth metal compound,
In the cross section perpendicular to the fiber axis direction of the single fiber, the shape of the core portion is an atypical cross-sectional shape having protrusions and grooves, and the number and dimensions of the protrusions satisfy the above (II) to (IV). .
(VI) Step of applying actual twist to the latent dense dye-sheath composite polyester fiber (VII) Step of obtaining a woven or knitted fabric using the latent dark dyeable sheath / core composite polyester fiber subjected to actual twist (VIII) The step (5) of subjecting the woven or knitted fabric to an alkali weight loss treatment (5) The step (V) comprises (IX) and (X). Production method.
(IX) A polyester oligomer is formed by esterifying a dicarboxylic acid component and a diol component, and then a phosphorus compound and an alkaline earth metal compound are added to the polyester oligomer, or a phosphorus compound and an alkali metal Step of adding a compound and an alkaline earth metal compound and then performing a polycondensation reaction to obtain a hardly soluble polyester resin composition (X) Disposing the hardly soluble polyester resin composition in the core, A step of obtaining a latent dark-dyeing core-sheath composite polyester fiber in which a core is formed in a cross-section perpendicular to the longitudinal direction of the fiber, and the shape of the core portion is a modified cross-sectional shape having a protrusion and a groove.

  The deep-dyed polyester woven or knitted fabric of the present invention is a modified cross-section fiber in which the polyester fiber that is a constituent fiber has fine pores on the surface, and further has specific protrusions and grooves, and has a specific range of twist coefficient. Since the real twist is applied, these synergistic effects significantly enhance the deep dyeability due to the accelerated multiple scattering of incident light.

It is a cross-sectional schematic diagram which shows one Embodiment of the unusual cross section of the single fiber of the highly dyeable polyester fiber which is a constituent fiber of the highly dyeable polyester woven or knitted fabric of this invention. It is the partial expansion schematic diagram of the single fiber of the deep dyeable polyester fiber which is a constituent fiber of the deep dyeable polyester woven or knitted fabric of the present invention.

Hereinafter, the present invention will be described in detail.
The present invention is a dark dyeable polyester woven or knitted fabric containing dark dyeable polyester fibers. In all the constituent fibers of the dark dyeable polyester woven or knitted fabric of the present invention, the dark dyeable polyester fibers are preferably contained in a proportion of 50% by mass or more, and more preferably contained in a proportion of 65% by mass. The structure of the woven fabric is not particularly limited, and examples thereof include a plain weave texture, a twill texture, or a satin texture obtained by an air jet loom, a rapier loom, a fly shuttle loom, a water jet loom, or the like. Moreover, as a structure | tissue of a knitted fabric, the knitting | organization structure | tissues, such as a tengu, kanoko, or smooth obtained with a circular knitting machine or a warp knitting machine, etc. are mentioned, for example.

  The polyester that is a raw material of the highly dyeable polyester fiber is, for example, polyethylene terephthalate, polybutylene terephthalate, polypropylene terephthalate, or polylactic acid. Such polyester is preferably made of a polyester resin in which 80 mol% or more of all structural units is ethylene terephthalate.

  In the present invention, the dark-dyeing polyester fiber is (a) an actual-shaped twisted fiber having a specific range of twist coefficient, and (b) a modified cross-section fiber having specific protrusions and grooves, C) It has specific fine pores on the surface of the single fiber. The present invention has been found and achieved for the first time that it is possible to achieve an unpredictable remarkable darkness due to the synergistic effects of (i) to (c).

  The relationship between (i) to (c) and the deep dyeing property will be described below. Usually, when light is incident on the surface of the polyester fiber, the incident light is reflected to cause glare, and a deep color or sufficient darkness cannot be expressed. However, in the present invention, irregularities appear on the fiber surface due to real twisting with a specific twisting coefficient, and further have a modified cross-sectional shape having protrusions and grooves, and micropores of a specific size and depth Is a woven or knitted fabric that contains fibers that exist at high density, so that when incident light is reflected on the surface of a single fiber, it is scattered and rescattered, and then the reflected light is incident on the fiber surface again. Can increase the light absorbed. That is, in order to promote the multiple scattering of incident light on the fiber surface and reduce the reflected light, an unpredictable synergistic effect of exhibiting excellent deep dyeability and deep hue is produced.

(A) is described below.
In addition to the effect of the irregular cross section and fine pores in the highly dyeable polyester fiber, it is necessary to twist the polyester fiber (actual twist). By twisting the polyester fiber and adding irregularities due to twisting to the yarn surface, coupled with the atypical cross-sectional shape and micropores described later, multiple scattering of incident light is promoted, so that there is a noticeable darkness. A synergistic effect is achieved.

The twist coefficient K of the highly dyeable polyester fiber is 3,000 to 30,000, preferably 5,000 to 25,000, and more preferably 8,000 to 15,000. If the twist coefficient is less than 3,000, the twist is not sufficient and the unevenness is not sufficiently developed, so that the deep dyeability is poor. Moreover, when it exceeds 30,000, the heat setting property in twisting deteriorates, and there is a problem that billiness and snare are generated and the processability of the weaving and knitting process is lowered. In addition, since the cross-sectional shape of the twisted yarn approaches a round cross-section, the deep dyeing may be deteriorated. In addition, the twist coefficient K is calculated | required by following formula (I).
K = T × D ^1/2 (I)
However, K is a twist coefficient, T is the number of twists (times / m), and D is a fineness (dtex).

  In addition, as a method of actually twisting a polyester fiber, if it is a method which can make a twist coefficient into the said range, it will not specifically limit, A conventionally well-known method can be used.

(B) is described below.
The single fiber of the highly dyeable polyester fiber is a fiber having an irregular cross-sectional shape. Specifically, as shown in FIG. 1, the cross-sectional shape of the dark-dyeing polyester fiber 1 is such that the protrusions 2 and the grooves 3 are alternately and substantially uniformly arranged on the surface, and on the surface of the fiber, A plurality (20 in FIG. 1) of protrusions continuous in the fiber axis direction are provided, and the same number of grooves as the protrusions exist between adjacent protrusions.

  The cross-sectional shape of the protrusion and the groove is rectangular or substantially trapezoidal. If the shape of the groove is, for example, a triangle, the difference in length between the bottom surface and the top surface of the protruding portion becomes large, and the protruding portion and the groove fit between the filaments. Is reduced, and multiple scattering of incident light is not promoted, resulting in poor deep dyeing.

  Moreover, the number (N) of protrusions is 10 to 32 on the circumference of the single fiber, and more preferably 16 to 25. When the number of protrusions is 10 or more, there are sufficient grooves for promoting multiple scattering of incident light, and therefore, the deep dyeing effect is further improved. On the other hand, if the number of protrusions is 32 or less, the protrusions are difficult to break, fiber fibrillation during wearing can be suppressed, and the effect of deep dyeing becomes even better.

  A preferable relationship between the width W and the height H of the protrusion will be described below. FIG. 2 is a partially enlarged cross-sectional view of a deeply dyeable polyester fiber (an irregular cross-section fiber). In FIG. 2, the line on the side surface of the protrusion is extended, the intersection of the circumscribed circle between the extended line and the apex of the protrusion is 4, 5, and the intersection with the inscribed circle at the deepest part of the groove is 4 ′, 5 ′. And Further, the midpoints of the line segment 4-5 and the line segment 4'-5 'are 6, 6'. And let the length of the line segment 4-5 be the width W of a projection part. The length of the line segment 6-6 'is the height H of the protrusion.

In the irregular cross-section fiber of the present invention, the width W (μm) and the height H (μm) of the protrusions satisfy the following formulas (III) and (IV).
0.3 ≦ W ≦ 3.0 (III)
0.5W ≦ H ≦ 3.0W (IV)
That is, the width W of the protrusion is in the range of 0.3 to 3 μm, and preferably 0.4 to 1.8 μm. When the width W of the protrusion is 0.3 μm or more, fibrillation of the fiber is suppressed and the deep dyeing property is excellent. Moreover, since the width | variety of a projection part does not become large too much that it is 3 micrometers or less, since the incident light to a groove | channel can fully be ensured, it is excellent in deep dyeing property.

  The height H of the protrusion is set in close relation to the width W of the protrusion. Specifically, it is in the range of 0.5 to 3 times the width W of the protrusion, and more preferably in the range of 0.6 to 2 times. If the height H of the protrusion is 0.5 times the width W or more, the depth of the groove will not be too shallow, and multiple scattering of incident light will be adequately made, so that it is excellent in darkness. It becomes. Moreover, since a protrusion part does not become large too much that it is 3 times or less, and fibrillation can be suppressed, the fall of dark dyeing property can be suppressed.

The above (c) will be described below.
In order to promote multiple scattering of incident light and enhance darkness, fine pores with a size and depth that appropriately correspond to the wavelength of visible light (380 to 780 nm) are present at a high density on the surface of a single fiber. It is necessary to.
The micropores formed on the surface of the polyester fiber of the present invention are present in a number of 10 or more in a 5 μm × 5 μm size region on the fiber surface, and preferably present in a number of 20 or more. More preferably, it is present in the number of 30 or more. When the number is 10 or more in a 5 μm × 5 μm size region on the fiber surface, the number of micropores is sufficient, so that multiple scattering of incident light is promoted. The upper limit of the number of micropores is not particularly limited, but is, for example, about 100, preferably 70 or less, and more preferably 50 or less.

  The major axis of the micropore is 0.9 μm or less, and the minor axis is 0.6 μm or less, preferably the major axis is 0.4 to 0.9 μm and the minor axis is 0.2 to 0.6 μm. When the major axis and the minor axis of the micropore are in the above range, multiple scattering of incident light is sufficiently promoted, and the deep dyeability is excellent.

  The depth of the fine holes is 100 to 400 nm, preferably 150 to 350 nm, and more preferably 200 to 300 nm. If the depth of the micropore is less than 100 nm, multiple scattering of incident light cannot be promoted sufficiently. Further, if the depth of the micropores exceeds 400 nm, the generated particle diameter necessary for micropore generation becomes coarse, and the micropores cannot be present at a high density on the single fiber surface. In addition, the depth of a micropore is the value measured in the location where the distance from the single fiber surface is the largest.

  The fineness of the deep dyeable polyester fiber is preferably in the range of 0.1 to 10.0 decitex as the single yarn fineness, more preferably in the range of 0.3 to 5.0 decitex, and in the range of 0.3 to 3.0 decitex. Is more preferable. If the single yarn fineness is 0.1 dtex or more, the width W of the protrusion is easily set to 0.6 μm or more, and multiple scattering of incident light is promoted, so that it is more excellent in deep dyeing. On the other hand, if it is 10.0 decitex or less, the texture becomes good.

  The total fineness of the highly dyeable polyester fiber is preferably 30 to 300 dtex, and more preferably 50 to 200 dtex. Here, if the total fineness is 30 dtex or more, the strength is more excellent. On the other hand, if it is 300 dtex or less, the texture becomes good.

The deep-dyed polyester woven or knitted fabric of the present invention is a polyester fiber that is remarkably excellent in deep-dyeing with an L ^* value of 12 or less when the effect of deep dyeing is evaluated using the L ^* value of CIELab. Here, the L * value serves as an index of color strength, and the smaller the value, the better the dyeability. In the present invention, the L * value is preferably 11 or less, and more preferably 10.5 or less. A method for measuring the L * value will be described in detail in Examples.

  The polyester woven or knitted fabric of the present invention subjected to the dyeing process is formed by laminating a film containing at least one resin of the group consisting of polyurethane resin, fluorine resin, and silicon resin ( It is preferable that further deep dyeing is applied. These resins are so-called low refractive index resins. By forming such a film, the light transmittance is increased and the regular reflection is reduced, so that multiple scattering is promoted and the deep dyeing property is further improved. In other words, it is a real-shaped twisted fiber with an irregular cross-section that has specific protrusions and grooves, uses fibers with specific fine pores on the surface of single fibers, and synergies with further deep dyeing. Due to the effect, it is remarkably excellent in the deep dyeability. The refractive index of the low refractive index resin is preferably 1.5 or less from the standpoint of darkness.

  Examples of the low-refractive index resin include a polyurethane-based resin comprising a block of propylene oxide and ethylene oxide or a random copolymerized polyether diol and hexamethylene diisocyanate, polypentadecafluorooctyl acrylate, polytetrafluoroethylene, polytrifluoroethyl acrylate. And fluorine resins such as polydimethylsilane, polymethylsilane, polydimethylsiloxane, and silicon resins such as polydimethylsiloxane.

An example of the method for producing the above-described highly dyeable polyester woven or knitted fabric of the present invention will be described below. The production method of the present invention includes, for example, the following steps (V) to (VIII).
(V) a step of preparing a latent highly dyeable core-sheath composite polyester fiber in which a hardly soluble polyester resin composition is disposed in the core and an easily soluble polyester resin is disposed in the sheath;
The hardly soluble polyester resin composition includes a hardly soluble polyester resin and generated particles having an average particle diameter of 0.05 to 0.5 μm,
The generated particles are derived from a phosphorus compound and an alkaline earth metal compound, or derived from a phosphorus compound, an alkali metal compound, and an alkaline earth metal compound,
In the cross section perpendicular to the fiber axis direction of the single fiber, the shape of the core portion is an atypical cross-sectional shape having protrusions and grooves, and the number and dimensions of the protrusions satisfy the above (II) to (IV). .
(VI) Step of applying actual twist to the latent dense dye-sheath composite polyester fiber (VII) Step of obtaining a woven or knitted fabric using the latent dark dyeable sheath / core composite polyester fiber subjected to actual twist (VIII) ) A step of subjecting the woven or knitted fabric to an alkali weight loss treatment

Step (V) will be described below.
Step (V) includes, for example, the following steps (IX) and (X).
(IX) A polyester oligomer is formed by esterifying a dicarboxylic acid component and a diol component, and then a phosphorus compound and an alkaline earth metal compound are added to the polyester oligomer, or a phosphorus compound and an alkali metal A step of adding a compound and an alkaline earth metal compound and then performing a polycondensation reaction to obtain a hardly soluble polyester resin composition. In this specification, an alkali metal compound and an alkaline earth metal compound are simply referred to as “metal”. Sometimes referred to as "compound".

(X) The above-mentioned hardly soluble polyester resin composition is arranged in the core, and the composite spinning is carried out so that the easily soluble polyester resin is arranged in the sheath, and the shape of the core in the cross section perpendicular to the fiber longitudinal direction is the protrusion and groove. For obtaining latently dyeable core-sheath composite polyester fiber having an irregular cross-sectional shape having

Step (IX) will be described below.
As the dicarboxylic acid, terephthalic acid can be mainly used. As long as the effects of the present invention are not impaired, other components may be copolymerized depending on the purpose. Components other than terephthalic acid include isophthalic acid, phthalic acid, phthalic anhydride, 5-sodium sulfoisophthalic acid, 5-tetrabutylphosphonium sulfoisophthalic acid, 4,4′-biphenyldicarboxylic acid, p-hydroxybenzoic acid, adipine Examples include acid, sebacic acid, 2,6-naphthalenedicarboxylic acid, 2,7-naphthalenedicarboxylic acid, and 1,4-cyclohexyldicarboxylic acid.

  As the diol component, ethylene glycol can be mainly used. As long as the effects of the present invention are not impaired, other components may be copolymerized depending on the purpose. As components other than ethylene glycol, 1,3-propanediol, 1,4-butanediol, diethylene glycol, 1,2-propylene glycol, 2,2-dimethyl-1,3-propanediol (neopentylene glycol), Examples include dipropylene glycol, 1,6-hexanediol, 1,4-cyclohexanedimethanol, dimethylolpropionic acid, poly (ethylene oxide) glycol, and poly (tetramethylene oxide) glycol.

  A polyester oligomer is obtained by esterifying dicarboxylic acid (dicarboxylic acid containing terephthalic acid as a main component) and diol (diol containing ethylene glycol as a main component). Here, when the dicarboxylic acid component and the diol component are terephthalic acid and ethylene glycol, respectively, the polyester oligomer includes bis (2-hydroxyethyl) terephthalate, and further includes 2 repeating units of ethylene terephthalate in one molecule. In addition, it represents a compound whose intrinsic viscosity, molecular weight, and degree of polymerization have not increased so much that it can be called polyethylene terephthalate, and the terminal is a carboxyl group or a hydroxyethyl group. Until such a polyester oligomer is formed, for example, the esterification reaction can be performed at a temperature of 250 ° C. for 3 to 8 hours. In order to detect the reaction rate of the esterification reaction, the amount of water produced can be measured.

  Polyester oligomers include polymellitic carboxylic acids such as trimellitic acid, trimesic acid, trimellitic anhydride, pyromellitic acid, trimellitic acid monopotassium salt, glycerin, pentaerythritol, sodium dimethylolethylsulfonate, potassium dimethylolpropionate Polyhydric hydroxy compounds such as may be copolymerized within a range that achieves the object of the present invention.

  A metal compound and a phosphorus compound are added to the polyester oligomer, and then a polycondensation reaction is performed to obtain a hardly soluble polyester resin composition containing a polyester resin that is hardly soluble in alkali. Here, together with the polycondensation reaction, a reaction between the phosphorus compound and the metal compound occurs, and the above-described generated particles that are insoluble in the polyester resin are formed.

  Regarding the order of addition of the phosphorus compound and the metal compound, the phosphorus compound may be added first, the phosphorus compound may be added later, or the phosphorus compound and the metal compound may be mixed and added simultaneously.

The addition amount of the metal compound is preferably ¹⁰ × 10 ^-4 ~100 × 10 -4 mol of the acid component 1 mol of constituting the polyester, more preferably 30 × ^{10 -4} ~80 × ¹⁰ -4 Is a mole. When the content is 10 × 10 ⁻⁴ or more, it is possible to form generated particles having a size sufficient to improve the deep dyeability of the polyester fiber, and to improve the deep dyeability on the surface of the polyester fiber. Therefore, the above-mentioned number of micropores necessary for the purpose can be developed. Since the generation of coarse particles can be suppressed when the amount is 100 × 10 ⁻⁴ mol or less, clogging of the filter for filtering the melted polyester resin composition during spinning does not occur, and the stability of the polyester fiber spinning process Can be kept good.

The addition amount of the phosphorus compound is preferably ¹⁰ × 10 ^-4 ~100 × 10 -4 mol of the acid component 1 mol of constituting the polyester, more preferably 20 × ^{10 -4} ~90 × ¹⁰ -4 Is a mole. When the content is 10 × 10 ⁻⁴ mol or more, it is possible to form generated particles having a size sufficient to make the polyester fiber dense, and the polyester fiber surface has good dark dyeing. It is possible to develop the above-mentioned number of micropores necessary for the purpose. When the amount is 100 × 10 ⁻⁴ mol or less, generation of coarse generated particles can be suppressed, so that clogging of the filter for filtering the melted polyester resin composition during spinning does not occur, and the polyester fiber spinning process Stability can be kept good. The molar ratio of the metal compound to the phosphorus compound is preferably (metal compound) / (phosphorus compound) = 0.5 to 1.5 in order to be excellent in yarn-making stability and latent dark dyeability.

  Examples of the phosphorus compound include phosphoric acids, phosphonic acids, and phosphinic acids. Among them, the average particle diameter of the produced particles is not too large, and the deep dyeing property (or latent dark dyeing property) of the polyester fiber and the stability of the spinning process are good. Phosphate esters are preferred. Among the phosphate esters, triethyl phosphate (triethyl phosphate) is particularly preferable from the viewpoint of excellent deep dyeability.

  The alkali metal compound is particularly an alkali metal salt of a carboxylic acid, and specific examples thereof include lithium acetate, sodium acetate, potassium acetate, lithium benzoate, sodium benzoate, or potassium benzoate. Among these, lithium acetate is preferable because the average particle diameter of the generated particles is in an optimal range and by-products during the polymerization reaction of the polyester can be suppressed.

  Alkaline earth metal compounds are, in particular, alkaline earth metal salts of carboxylic acids. Specific examples thereof include magnesium acetate, calcium acetate, magnesium oxalate, calcium propionate, calcium stearate, magnesium stearate, calcium benzoate. Or manganese acetate. In particular, when a magnesium salt of carboxylic acid is used, the particle diameter of the formed particles formed in the polyester resin is not excessive, and the process for producing a deep dyeable and latent dyeable core-sheath composite polyester fiber is not necessary. It is preferable because stability is improved. Of these, magnesium acetate is particularly preferred because of its excellent deep dyeability and handleability.

  A preferred combination of a phosphorus compound and a metal compound is a polyester fiber that controls the average particle diameter of the generated particles within the above range and has a markedly excellent dark dyeability (latent dark dyeable core-sheath composite polyester fiber, dark dyeable polyester fiber). From the viewpoint of obtaining the above, a combination of a phosphate ester and a metal salt of acetic acid is preferable, more preferably a combination of triethyl phosphate (triethyl phosphate) and magnesium acetate, and in addition to these, lithium acetate is used in combination Is most preferred. In addition, when lithium acetate is used alone as the metal compound, the generated particles tend to be too coarse. That is, in the present invention, in order to achieve a synergistic effect of controlling the average particle diameter of the generated particles within the above range and remarkably improving the deep dyeability, triethyl phosphate (triethyl phosphate) as a phosphorus compound and a metal compound As a combination, magnesium acetate and lithium acetate are most suitable.

  Subsequently, a polycondensation catalyst (for example, ethylene glycol solution) is added and a polycondensation reaction is carried out to obtain a polyester resin composition. If necessary, an additive such as a copolymerization monomer or a coloring inhibitor may be added to the polycondensation reaction system as an ethylene glycol solution or a dispersion. In this case, the polycondensation reaction is started by distilling off ethylene glycol (removing ethylene glycol under reduced pressure), and the reaction is continued while distilling off. it can. Here, the production | generation of production | generation particle | grains is started after a polycondensation catalyst is added. And the solubility of a product falls as a solution is distilled off, and this product precipitates as a particle.

  The intrinsic viscosity (intrinsic viscosity) of the polyester resin composition is preferably 0.5 to 1.5 dL / g. When the intrinsic viscosity is within this range, the physical properties of the polyester fiber obtained by spinning the resin composition do not deteriorate, and the polyester resin composition or the polyester fiber is easy to produce.

  The combination of the phosphorus compound and the alkali metal compound and / or the alkaline earth metal compound is an alkali metal salt of phosphate ester and acetic acid from the viewpoint of controlling the average particle size of the generated particles in the range of 0.05 to 0.50 μm. Alternatively, a combination of alkaline earth metal salts is preferable, a combination of triethyl phosphate and magnesium acetate is more preferable, and in addition to these, lithium acetate is most preferably used in combination.

  The generated particles are derived from a phosphorus compound and an alkaline earth metal compound, or derived from a phosphorus compound, an alkali metal compound, and an alkaline earth metal compound. In the present invention, “latent dark dyeing” means that the core-sheath composite polyester fiber as described above is subjected to an alkali weight reduction treatment to elute the sheath part and drop off the generated particles to form micropores on the surface of the single fiber. It refers to the deep dyeing manifested by formation.

  The produced particles are different from known inert fine particles such as silica fine particles, and are separately produced in a polyester resin composition production stage (synthetic reaction system) without previously reacting a phosphorus compound and a metal compound described later. By being added to the particles, the particles are formed by the reaction between the phosphorus compound and the metal compound. Compared with known inert fine particles, the generated particles are suppressed from coarsening due to agglomeration, so that fine pores having an appropriate size and depth can be formed at a high density. The effect (excellent deep dyeability, latent deep dyeability) can be expressed more remarkably.

  The average particle size of the generated particles is 0.05 to 0.5 μm, more preferably 0.08 to 0.4 μm. When the average particle diameter is in the above range, when a deeply dyeable polyester fiber is obtained by alkali weight loss treatment, fine pores having an appropriate size and depth as described below are high density (number of specific ranges). The resultant particles can be formed, and the filter for filtering the molten polymer is not clogged when spinning the latent dark-dyeing core-sheath polyester fiber, and the increase in pressure or the occurrence of yarn breakage can be suppressed. The average particle diameter of the generated particles can be controlled within the above range by, for example, making the combination of a phosphorus compound and a metal compound or the addition amount of a phosphorus compound and a metal compound preferable. A preferred combination of the phosphorus compound and the metal compound in the present invention, and the addition amount of the phosphorus compound and the metal compound will be described later. Further, the size, depth, and number range of the micropores in the present invention will be described later.

Step (X) will be described below.
A known spinning method (for example, melt spinning method) is adopted, a preferable composite spinning nozzle is selected, the hardly soluble polyester resin composition obtained in the step (IX) is arranged in the core, and the easily soluble polyester resin is sheathed. By carrying out composite spinning (for example, melt spinning) so as to be arranged in the part, latent deep-dyeing core-sheath composite type polyester fiber as a multifilament yarn is obtained.

  The latent highly dyeable core-sheath composite polyester fiber is one in which a hardly soluble polyester resin composition is disposed in the core portion and an easily soluble polyester resin is disposed in the sheath portion. And the shape of the core part in the cross section perpendicular | vertical of the fiber axis direction of a single fiber is a deformed cross-sectional shape which has a projection part and a groove | channel. In the present invention, “easily soluble” means that elution with an alkali compound (alkali) is easy, and “slightly soluble” means that elution with an alkali is not easy. Note that, in the latent dark-dyeing core / sheath composite polyester fiber, the shape of the core is substantially the same as the cross-sectional shape of the dark-dyeing polyester fiber described above. This is because the sheath part of the latent deep-dyeing core-sheath composite polyester fiber is eluted with a basic compound (alkali), and further, the core part surface is eluted to drop off the generated particles, thereby being included in the woven or knitted fabric of the present invention. It is because it becomes a deep dyeable polyester fiber.

  The easily soluble polyester resin preferably has a dissolution rate in a solvent such as alkali of 5 times or more faster than the hardly soluble polyester resin described later. Therefore, the easily soluble polyester resin is an aromatic dicarboxylic acid component in which 1 to 3 mol% of the dicarboxylic acid component has a sulfonate group, and contains 5 to 15 mass% of a polyalkylene glycol having an average molecular weight of 1000 to 10,000. It is preferable.

  Examples of the aromatic dicarboxylic acid component having a sulfonate group include 5-sodium sulfoisophthalic acid, 5-sodium sulfoterephthalic acid, 5-potassium sulfoisophthalic acid, 5-sodium sulfoterephthalic acid, 5-lithium sulfoisophthalic acid, 5- Examples include phosphonium sulfoisophthalic acid. When the aromatic dicarboxylic acid component having a sulfonate group is 1 mol% or more of the dicarboxylic acid component, the dissolution rate in alkali is sufficiently high. When it is 3 mol% or less, the yarn-forming property is better even at high speed, and troubles such as yarn breakage can be suppressed.

  The polyalkylene glycol preferably has an average molecular weight of 1000 to 10,000. When the average molecular weight is 1000 or more, the glass transition point of the readily soluble polyester resin does not decrease, and it becomes difficult for fusion to occur in the spinning process. When it is 10,000 or more, the compatibility becomes good and it is easy to contain it uniformly.

  When the polyalkylene glycol content is 5% by mass or more, the dissolution rate in alkali is sufficiently high. When the content is 15% by mass or less, the spinning speed is kept sufficiently high while the spinning property is improved, and troubles such as yarn breakage can be suppressed in the spinning process.

  As the easily soluble polyester resin, for example, 1 to 3 mol% of the dicarboxylic acid component is an aromatic dicarboxylic acid component having a sulfonate group, and 5 to 15% by mass of a polyalkylene glycol having an average molecular weight of 1000 to 10,000 is contained. A polyester resin can be used.

  A known spinning method (for example, melt spinning method) is adopted, a preferred spinning nozzle is selected, the hardly soluble polyester resin composition is arranged in the core portion, and the easily soluble polyester resin is arranged in the sheath portion. In this way, composite spinning (for example, melt spinning) is performed. And you may stretch after winding up as an undrawn yarn by a well-known method, and you may wind up, after extending | stretching without winding once after discharge. Moreover, after winding up at a speed | rate of 3000-9000m / min, you may use for a yarn process or a weaving knitting as it is, without extending | stretching separately.

  The spinning conditions are not particularly limited. For example, an undrawn yarn once wound at a spinning temperature of 270 to 300 ° C., a take-up speed of 1000 to 2000 m / min, and a drawing temperature of 70 to 100 ° C. Examples thereof include an FDY method in which the temperature is 120 to 190 ° C., the drawing speed is 200 to 1000 m / min, and the draw ratio is drawn at about 0.65 to 0.85 times the maximum draw ratio of the undrawn yarn. The maximum draw ratio refers to the ratio at which the undrawn yarn is drawn until it is cut under conditions of a drawing temperature of 80 ° C., a heat setting temperature of 145 ° C., and a drawing speed of 600 m / min.

  As the spinning and stretching methods, for example, POY method (method of winding as a semi-unstretched yarn by high-speed spinning of 2000 m / min or more), HOY method (super-high-speed spinning of 5000 m / min or more, highly oriented unstretched) A method of winding as a yarn) or a spin draw method (a method of spinning at 200 m / min or more and stretching continuously without winding).

  The mass ratio between the easily soluble polyester resin and the hardly soluble polyester resin composition is preferably in the range of (easy soluble polyester resin) and (slightly soluble polyester resin composition) = 5: 95 to 40:60, particularly 10:90 to 30:70 is preferred. When the easily soluble polyester resin is 5% by mass or more, it is easy to obtain a modified cross-sectional shape having the protrusions and grooves of the present invention, and when it is 40% by mass or less, the strength is sufficient.

Step (VI) will be described below.
Twist (actual twist) is applied to the latent dark-dyeing core / sheath composite polyester fiber obtained in step (V) to obtain a twisted yarn (strongly twisted yarn). The twisting condition is not particularly limited as long as it is carried out in accordance with a conventional method. As described above, the actual twisting is performed under such a condition that a polyester fiber having a twist coefficient K in the range of 10,000 to 30,000 is obtained. Can be applied. Furthermore, you may perform various processes, such as false twisting or an air entanglement process, as needed.

Step (VII) will be described below.
The method for forming the knitted or knitted fabric may be performed according to a conventional method, and is not particularly limited. For example, in the case of a woven fabric, an air jet loom, a rapier loom, a fly shuttle loom, a water jet loom, or the like can be used for weaving with a woven structure such as a plain weave structure, a twill structure, or a satin structure. In addition, if it is a knitted fabric, it can be knitted with a knitting structure such as a tengu, kanoko or smooth using a circular knitting machine or a warp knitting machine.

Step (VIII) will be described below.
The woven or knitted fabric obtained in the step (VII) is subjected to an alkali weight loss treatment using an alkali compound. Before being subjected to the alkali weight loss treatment, if necessary, desizing, scouring, and presetting may be performed according to a conventional method.

  The alkali weight loss treatment is performed to elute the sheath portion of the latent dark-dyeing core-sheath composite polyester fiber to form a modified cross-section fiber, and further drop the generated particles to obtain fine pores. In other words, in the present invention, the micropores formed on the surface of the highly dyeable polyester fiber are, for example, particles formed by spinning the polyester resin composition on which the generated particles are formed into fibers and then treating the fibers with an alkaline aqueous solution. Refers to the fine pores obtained by eluting What is necessary is just to perform an alkali weight loss process according to a conventional method, and can be performed using the aqueous solution of an alkali compound. Examples of the alkali compound used here include sodium hydroxide, potassium hydroxide, tetramethylammonium hydroxide, sodium carbonate and the like. Of these, sodium hydroxide and potassium hydroxide are particularly preferable.

  Although the density | concentration of the aqueous solution of an alkali compound changes with the kind of alkali compound, a process condition, etc., the range of 0.1-40 mass% is preferable normally, and the range of 1-30 mass% is especially preferable. The alkali weight loss treatment temperature is preferably in the range of 40 to 120 ° C, particularly preferably in the range of 60 to 100 ° C. The treatment time is preferably in the range of 1 minute to 4 hours.

  The alkali weight loss rate is not particularly limited, and is determined by, for example, the mass ratio of the easily soluble polyester resin and the hardly soluble polyester resin, the addition amount of the metal compound and the phosphorus compound, for example, 6 to 55. It is preferably in the range of mass%.

  The deep dyeable polyester woven or knitted fabric of the present invention obtained as described above can be dyed. The dyeing process may be performed in accordance with a conventional method, and the method is not particularly limited. However, if black dyeing is used, the L * value can be reduced to obtain a deep dyeing effect as compared with the case of using other colors. it can. Examples of the dye include disperse dyes, such as “Dianix Black HG-FS” manufactured by DiStar, “Kayalon Polyester Black BRN-SF 200” manufactured by Nippon Kayaku Co., Ltd., and “Kiwalon Polyester Black KG-SE Liq”. Or the like. The dye concentration at the time of dyeing is not particularly limited and is, for example, 5 to 15% o.d. m. The range of f. The dyeing machine used for the dyeing process is not particularly limited, and for example, a high pressure liquid dyeing machine or the like can be used. The dyeing temperature is preferably in the range of 120 to 135 ° C, and the time is preferably in the range of 30 to 60 minutes.

  Further darkening (dense processing) may be performed by laminating and forming a film containing a low refractive index resin on the surface of the deeply dyeable polyester woven or knitted fabric of the present invention after dyeing. As a commercial item of the processing agent for forming the low refractive index resin film, for example, “Lighttex GR-2” manufactured by Kitahiro Chemical Co., Ltd. or “KM-9771” manufactured by Shin-Etsu Chemical Co., Ltd. “Swat TR-420” manufactured by Kitahiro Chemical Co., Ltd. includes a polyurethane resin, and “Vasotex FS-370E” manufactured by Meisei Chemical Industries Co., Ltd. includes a fluororesin. In particular, from the viewpoint of deep dyeability and handleability, fluorine-based resins such as polypentadecafluorooctyl acrylate, polytetrafluoroethylene, and polytrifluoroethyl acrylate are preferable.

  As a method for forming the resin film, for example, a padding method is preferable. For example, it is preferable that the fluorine-based resin is adhered at a solid content of 0.2 to 1.0% with respect to 100% by mass of the woven or knitted fabric, and more preferably 0.3 to 0.8%. When the solid content is 0.2% or less, it becomes more excellent due to the deep dyeing property. If it is 1.0% or less, a decrease in dyeing fastness can be suppressed. Although it dries after padding, as drying conditions, it is preferable to set it as the temperature of 100-140 degreeC, for 30 to 180 seconds, for example. When the drying temperature is 100 ° C. or higher, the reaction rate of the resin falls within an appropriate range, and a further darkening effect can be realized. Moreover, when it is 140 degrees C or less, formation of a resin film becomes uniform and it can suppress the color nonuniformity at the time of dyeing | staining, or omission of resin. After drying, heat treatment can be performed in the range of 150 to 190 ° C. as necessary.

  The deep dyeable polyester woven or knitted fabric of the present invention is remarkably excellent in deep dyeability. Specifically, the L value when black dyeing is performed is 12 or less, preferably 11.5 or less, more preferably 11.0, and particularly preferably 10.5 or less. Therefore, it is suitable for apparel textile products that require deep dyeing, such as apparel (particularly black formal), swimwear, sports inners, lingerie, or foundations.

  Hereinafter, the present invention will be described in detail according to examples. The present invention is not limited to this example. The measurement method or evaluation method in the examples of the present invention is as follows.

(1) Intrinsic Viscosity It was measured based on a conventional method under the condition of a temperature of 20 ° C. using a mixture of equal mass of phenol and ethane tetrachloride as a solvent.

(2) L value L value was measured with respect to the woven or knitted fabric using a color difference meter (Spectrophotometer Color-Eye-3100 manufactured by X-Rite). The L value indicates that the smaller the value, the deeper the deep color.

(3) Number of micropores Ten monofilaments of dark-dyeing polyester fibers were randomly collected from the obtained woven or knitted fabric. The surface of this single fiber was photographed at a magnification of 10,000 using a scanning electron microscope (SEM). An inspection area of 5 μm by 5 μm was set at random in the photographed photo, the number of micropores present in this area was counted, and the average value of 10 was calculated.

(4) Size of micropores In the photograph taken in (3) above, 30 micropores present on the fiber surface were randomly selected. The length in the longitudinal direction of the fiber was taken as the major axis, and the length in the direction perpendicular to the longitudinal direction was taken as the minor axis, and the average value of each was determined.

(5) Depth of micropore One single fiber of deeply dyeable polyester fiber was collected from the woven or knitted fabric and cut perpendicularly to the fiber axis direction (longitudinal direction). This cut surface was photographed at a magnification of 10,000 using a scanning electron microscope (SEM). In this photograph, 30 micropores present on the fiber surface were selected at random, the depth of the micropores was measured, and the average value was obtained. Note that the depth of the micropores was measured at the point where the distance from the single fiber surface was the largest.

(6) Number and size of protrusions (width and height)
One dark-dyeing polyester fiber was collected from the woven or knitted fabric and cut perpendicularly to the fiber axis direction (longitudinal direction). This cross section was photographed with a scanning electron microscope (SEM) (magnification: 10,000 times) and counted or measured on the photograph.

<Example 1>
In the following manner, a polyester resin composition A hardly soluble in alkali was obtained.
A slurry of terephthalic acid (TPA) and ethylene glycol (EG) (molar ratio TPA: EG = 1.6) is continuously supplied to an esterification reactor in which a low polyester polymer exists, at a temperature of 250 ° C. and a pressure The reaction was carried out under a condition of 50 hPa to continuously obtain a polyester low polymer having an esterification reaction rate of 95%. This polyester low polymer was put into a polycondensation reaction can, and the inside of the container was replaced with nitrogen. Subsequently, antimony trioxide as a polycondensation catalyst is 2.0 × 10 ⁻⁴ mol per 1 mol of the acid component constituting the polyester, and triethyl phosphate as the phosphorus compound is 84 × per mol of the acid component constituting the polyester. 10 ^-4 mol, 35 × ^{10 -4} mol of magnesium acetate relative to the acid component 1 mol of constituting the polyester, so that the lithium acetate becomes 35 × ^{10 -4} mol of the acid component 1 mol of constituting the polyester and Was added. The pressure was gradually reduced to 1.2 hPa or less after 1 hour. The polycondensation reaction was carried out for 4 hours with stirring under these conditions, and then discharged and pelletized by a conventional method to obtain a polyester resin composition A having an intrinsic viscosity of 0.69 dL / g.

  A polyester resin prepared by copolymerizing 2.0% by mass of sodium sulfonate and 6.0% by mass of polyethylene glycol with respect to polyester as a polyester resin that is easily soluble in alkali.

  A die capable of spinning a modified cross-section fiber so as to be a core-sheath composite fiber, in which a hardly soluble polyester resin composition A is arranged in the core and a polyester resin easily soluble in alkali is arranged in the sheath. Used to spin. Specifically, from a die having 24 spinning holes drilled, which can spin a modified cross-section fiber composed of a core portion having 20 protrusions and grooves and a sheath portion arranged around the core portion. Spinned. The spun yarn was cooled by an air flow and passed through an oiling device (oil supply device) to apply the oil.

  The yarn was taken up at a spinning speed of 3250 m / min (84 dtex 24f). The obtained yarn was drawn 1.5 times with a conventional drawing machine via a heat roller at 85 ° C., and further heat treated with a heat plate at 170 ° C. to obtain a drawn yarn (56 dtex24f). ). In this polyester fiber, the composite ratio (mass ratio) of the core part and the sheath part was core part: sheath part = 81: 19. Subsequently, the obtained drawn yarn was twisted at a twist count of 1500 times / m with a conventional twisting machine to obtain a polyester fiber (latent dark-dyeing core-sheath composite polyester fiber) which is a strong twisted yarn (twisting coefficient K; 11,000).

  Next, the resulting latently dyeable core-sheath composite polyester fiber was knitted into a tubular knitted fabric using a knitting machine (manufactured by Koike Machine Works, number of needles: 300, hook diameter: 3.5 inches), and 40 g A book containing dark-dyeing polyester fibers, using an alkaline solution containing sodium hydroxide at a ratio of 1 / L (bath ratio 1:30), treated with alkali at a treatment temperature of 100 ° C. for 60 minutes (weight loss rate 40%). The deep dyeable polyester woven or knitted fabric of the invention was obtained.

Next, staining was performed by the following method.
<Dyeing conditions>
(concentration)
Dye Star “Dianix Black HG-FS (200%)” 7.5% o.d. m. f
“Nikka Sun Salt SN-130” (dispersion aid) by Nikka Chemical Co., Ltd. 0.5g / L
Acetic acid 0.2cc / L
(Bath ratio)
Sample: Bath amount = 1: 40
(Dyeing temperature)
135 ° C x 30 minutes

<Reduction cleaning conditions>
(concentration)
Hydrosulfite 2g / L
Sodium hydroxide 2g / L
"Sun Mall FL" (Non-active activator) manufactured by Nikka Chemical Co., Ltd. 1g / L
(Bath ratio)
Sample: Bath amount = 1: 40
(Washing temperature)
80 ° C x 20 minutes

Next, the dyed tubular knitted fabric was padded with the following processing agent to form a resin film made of a fluororesin, and was further subjected to deep dyeing. The drying temperature was 120 ° C. and the drying time was 120 seconds. The heat treatment temperature was 170 ° C. and the heat treatment time was 60 seconds.
(Processing agent)
“Vasotex FS-370E” 30 g / L (fluorine resin solution having a solid content of 17% by mass) manufactured by Meisei Chemical Co., Ltd.
“Texport SN-10” manufactured by Nikka Chemical Co., Ltd. (oligomer removal agent) 2 g / L

<Example 2>
Except not having performed the deep dyeing process (except not having formed the resin film containing a fluororesin), operation similar to Example 1 was performed and the deep dyeable polyester woven fabric of Example 2 was obtained. .

<Example 3>
The deep dyeing of Example 3 was carried out in the same manner as in Example 1, except that the number of twists in the strong twist condition of the latent dyeable core / sheath composite polyester fiber was 500 times / m and the twist coefficient K was 3673. A woven polyester knitted fabric was obtained.

<Example 4>
The same procedure as in Example 1 was performed except that the alkali weight loss condition was a sodium hydroxide ratio of 20 g / L, a bath ratio of 1:30, a treatment temperature of 100 ° C., a time of 60 minutes, and a weight loss ratio of 30%. The dark-dyed polyester woven or knitted fabric of Example 4 was obtained.

<Example 5>
Except not having performed the deep dyeing process (except not having formed the resin film containing low refractive index resin), operation similar to Example 4 was performed and the deep dyeable polyester woven or knitted fabric of Example 5 was obtained. It was.

<Example 6>
The same procedure as in Example 4 was performed except that the twisting coefficient K was set to 3673 by setting the number of twists in the strong twisting condition of the latent dark-dyeing core / sheath composite polyester fiber to 500 times / m. A dyeable polyester woven or knitted fabric was obtained.

<Comparative Example 1>
A woven or knitted fabric was obtained by performing the same operation as in Example 1 except that the number of twists was set to 400 T / m and the twist coefficient was set to 2992 for the latent deep-dyed core-sheath composite polyester fiber.

<Comparative example 2>
The knitted or knitted fabric of Comparative Example 2 was carried out in the same manner as in Example 1 except that the polyester resin composition A, which was hardly soluble in alkali, was replaced with ordinary polyethylene terephthalate (polyester resin containing no produced particles). Got.

<Comparative Example 3>
The alkali weight loss conditions were the same as in Example 1 except that the sodium hydroxide ratio was 20 g / L, the bath ratio was 1:30, the treatment temperature was 100 ° C., the treatment time was 30 minutes, and the alkali weight loss rate was 25%. As a result, a woven or knitted fabric of Comparative Example 3 was obtained.

<Comparative Example 4>
The nozzle used was changed to a fiber having a round cross section, and the polyester resin composition A was spun by a conventional method using a conventional melt spinning machine to obtain an undrawn yarn having a round cross section (84 dtex 24f). The obtained yarn was drawn by a conventional drawing machine by a conventional drawing machine to obtain a polyester fiber as a drawn yarn (56 dtex 24f). Next, the obtained drawn yarn was subjected to actual twisting at a twist count of 1500 T / m with a conventional twisting machine to obtain a strong twisted yarn having a twisting factor of 11,000.

Next, the obtained strong twisted yarn was knitted into a cylindrical knitted fabric using a knitting machine (manufactured by Koike Machinery Co., Ltd., number of needles: 300, hook diameter: 3.5 inches), and sodium hydroxide at a rate of 20 g / L. An alkali solution (bath ratio 1:30) was used, and an alkali weight reduction treatment was performed at a treatment temperature of 100 ° C. for 30 minutes (weight loss rate 20%). This was stained under the following conditions.
<Dyeing conditions>
(concentration)
Dye Star “Dianix Black HG-FS (200%)” 7.5% o.d. m. f
“Nikka Sun Salt SN-130” (dispersion aid) by Nikka Chemical Co., Ltd. 0.5g / L
Acetic acid 0.2cc / L
(Bath ratio)
Sample: Bath amount = 1: 40
(Dyeing temperature)
135 ° C x 30 minutes

<Reduction cleaning>
(concentration)
Hydrosulfite 2g / L
Sodium hydroxide 2g / L
"Sun Mall FL" (Non-ion activator) 1g / L made by Nikka Chemical
(Bath ratio)
Sample: Bath amount = 1: 40
(Washing temperature)
80 ° C x 20 minutes

The dyed tube knitted fabric was deeply dyed by padding using the following processing agent. The drying temperature was 120 ° C., the time was 120 seconds, the heat treatment temperature was 170 ° C., and the heat treatment time was 60 seconds.
(Processing agent)
“Vaso-Tex FS-370E” (fluorine resin solution having a solid content of 17% by mass) 30 g / L
“Texport SN-10” manufactured by Nikka Chemical Co., Ltd. (oligomer removal agent) 2 g / L

  Various evaluations were performed on the woven and knitted fabrics obtained in Examples 1 to 6 and Comparative Examples 1 to 4. The evaluation results are also shown in Table 1.

  As is apparent from Table 1, in Examples 1 to 6, woven or knitted fabrics having an L * value of 12 or less and excellent in high dyeability were obtained. In particular, Example 1 was more excellent in the deep dyeability due to the synergistic effect of forming the low-refractive-index resin film by using the deep-dyeing polyester fiber as a strong twisted yarn and further applying the deep dyeing process.

  In Comparative Example 1, since the dark-dyeing polyester fiber was not actually twisted, a certain dark-dyeing property was obtained, but the L * value was higher than that in Example 1, and the dark-dyeing effect was inferior. It was.

  In Comparative Example 2, since the polyester fiber having an irregular cross-sectional shape but not having micropores was used, the L * value was high and the dark dyeing effect was inferior. In Comparative Example 3, a polyester fiber having an atypical cross-sectional shape and having fine pores was used. However, the width of the protrusion was excessively wide and the height of the protrusion was low, resulting in inferior darkness. .

  In Comparative Example 4, since the polyester fiber having a fine hole on the surface of the single fiber but having a round cross-sectional shape was used, the reflection of light was increased. It became inferior.

DESCRIPTION OF SYMBOLS 1 Dark-dyeing polyester fiber 2 Protrusion part 3 Grooves 4, 5 Intersection 4 ', 5' of the line of a protrusion part and the circumscribed circle of a vertex of a protrusion part and the inscribed circle of the deepest part of a groove Intersection 6 Midpoint 6 'of line 4-5 End point of line 4'-5'

Claims (5)

A dark-dyeing polyester woven or knitted fabric containing dark-dyeing polyester fibers,
The dark-dyeing polyester fiber has a twist coefficient K calculated by the following formula (I) of 3,000 to 30,000 and is actually twisted.
K = T × D ^1/2 (I)
(However, K: Twisting coefficient, T: Twisting times (times / m), D: Fineness (dtex))
The deep dyeable polyester fiber has fine pores on the surface of a single fiber,
The number of the micropores is 10 or more in a 5 μm × 5 μm size region on the fiber surface, the major axis of the micropore is 0.9 μm or less, the minor axis is 0.6 μm or less, and the depth is 100 to 100 μm. 400 nm,
The single fiber of the dark-dyeing polyester fiber is a modified cross-section fiber in which protrusions and grooves are alternately and substantially uniformly arranged on the surface, and the protrusions and the grooves have a rectangular or substantially cross-sectional shape. It has a shape and is continuous in the fiber axis direction.
A deep dyeable polyester woven or knitted fabric characterized in that the number and dimensions of the protrusions simultaneously satisfy the following formulas (II) to (IV):
10 ≦ N ≦ 32 (II)
0.3 ≦ W ≦ 3.0 (III)
0.5W ≦ H ≦ 3.0W (IV)
(Where N is the number of protrusions, W is the width of the protrusion (μm), and H is the height of the protrusion (μm))   2. The deep-dyed polyester woven or knitted fabric according to claim 1, wherein a film containing at least one resin of a group consisting of a polyurethane resin, a fluorine resin, and a silicon resin is laminated on the surface.   The deep dyeable polyester woven or knitted fabric according to claim 1 or 2, wherein the L value when black dyeing is performed is 12 or less. A method for producing the dark-dyeing polyester woven or knitted fabric according to any one of claims 1 to 3, comprising the following steps (V) to (VIII):
(V) a step of preparing a latent highly dyeable core-sheath composite polyester fiber in which a hardly soluble polyester resin composition is disposed in the core and an easily soluble polyester resin is disposed in the sheath;
The hardly soluble polyester resin composition includes a hardly soluble polyester resin and generated particles having an average particle diameter of 0.05 to 0.5 μm,
The generated particles are derived from a phosphorus compound and an alkaline earth metal compound, or derived from a phosphorus compound, an alkali metal compound, and an alkaline earth metal compound,
In the cross section perpendicular to the fiber axis direction of the single fiber, the shape of the core portion is an atypical cross-sectional shape having protrusions and grooves, and the number and dimensions of the protrusions satisfy the above (II) to (IV). .
(VI) Step of applying actual twist to the latent dense dye-sheath composite polyester fiber (VII) Step of obtaining a woven or knitted fabric using the latent dark dyeable sheath / core composite polyester fiber subjected to actual twist (VIII) ) A step of subjecting the woven or knitted fabric to an alkali weight loss treatment The method for producing a deep dyeable polyester woven or knitted fabric according to claim 4, wherein the step (V) includes (IX) and (X).
(IX) A polyester oligomer is formed by esterifying a dicarboxylic acid component and a diol component, and then a phosphorus compound and an alkaline earth metal compound are added to the polyester oligomer, or a phosphorus compound and an alkali metal Step of adding a compound and an alkaline earth metal compound and then performing a polycondensation reaction to obtain a hardly soluble polyester resin composition (X) Disposing the hardly soluble polyester resin composition in the core, A step of obtaining a latent dark-dyeing core-sheath composite polyester fiber in which a core is formed in a cross-section perpendicular to the longitudinal direction of the fiber, and the shape of the core portion is a modified cross-sectional shape having a protrusion and a groove.