JP2006183163A - Polyester latently crimpable conjugated fiber - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a polyester latently crimpable conjugated fiber that has good fiber-forming property, good high-order processability because the elicitation of the crimp in drawing is suitably suppressed and can produce fabrics having satisfactory stretchability, excellent feeling and good appearance. <P>SOLUTION: In the latent crimpable conjugated fiber in which two kinds of polyester components having different intrinsic viscosity are laminated side by side, the difference of the intrinsic viscosity between the high viscosity and the low viscosity is in the range of 0.1 to 0.4; the crimping rate is more than 1.5% after treatment with boiling water for 20 min under the load of 17.6 μN/dtex; a crimping rate is from 30 to 50% after treatment with boiling water for 30 min under the load of more than 1.5 cN/dtex; the strength is more than 1.5 cN/dtex; and the elongation is from 30 to 70%. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a polyester latent crimpable conjugate fiber in which two types of polyesters having different intrinsic viscosities are bonded to each other in a side-by-side manner. More specifically, the present invention relates to a polyester latent crimpable conjugate fiber that is excellent in yarn-making property and high-order processability, has high stretch performance, and has a texture such as firmness and stiffness, and an appearance with few defects.

  Polyester composite fibers obtained by compounding polyesters having different intrinsic viscosities side by side are used in clothing fabrics as fiber materials having latent crimping performance. In order to obtain a polyester composite fiber that imparts appropriate stretchability to the fabric, the difference in intrinsic viscosity between the two types of polyester is increased, and the difference in thermal shrinkage when made into fibers is increased to sufficiently impart latent crimpability. It is necessary to keep it.

  For example, in Japanese Patent No. 3119389, a deep color is produced by producing a woven or knitted fabric using a latent crimped yarn having a crimp rate exceeding 50% after 30 minutes of boiling water treatment under a load of 1.5 μN / dtex. It is shown that a woven or knitted fabric having a good texture can be obtained.

  However, under the load of 1.5 μN / dtex, the latent crimped yarn having a crimp rate of more than 50% after being treated for 30 minutes with boiling water is already in the coiled state when the wound yarn is wound up as a drawn yarn. Will be presented. When unwinding such a drawn yarn from a package and twisting or weaving or knitting, it may be caught by a guide or the like of the yarn guide and broken, or it may appear as a dyeing defect after weaving and knitting due to excessive distortion. , Causing a malfunction. For this reason, improvement in the surface of the handleability in high-order processing is desired.

Japanese Patent No. 3119389 JP 2000-144518 A

  The present invention has been made against the background of the above-described prior art, and the purpose thereof is good yarn-making property, and since it is possible to moderately suppress the manifestation of crimp in stretching, high-order workability is good, and An object of the present invention is to provide a polyester latent crimpable fiber from which a fabric having sufficient stretchability and excellent texture and appearance can be obtained.

As a result of intensive studies in view of the above-described prior art, the present inventors have completed the present invention. That is, an object of the present invention is a latent crimpable conjugate fiber in which two types of polyester components having different intrinsic viscosities are bonded to a side-by-side type, and the intrinsic viscosity of a high-viscosity polyester component and a low-viscosity polyester component. This is achieved by a polyester latent crimpable composite fiber characterized in that the difference is in the range of 0.1 to 0.4 and the following requirements (a) to (d) are simultaneously satisfied.
(A) Crimp rate after treatment with boiling water for 20 minutes under a load of 17.6 μN / dtex is 1.5% or more and less than 25% (b) Crimp after treatment with boiling water for 30 minutes under a load of 1.5 μN / dtex (C) Strength is 1.5 cN / dtex or more (d) Elongation is 30% or more and 70% or less

  According to the present invention, it is possible to provide a polyester latent crimpable conjugate fiber excellent in yarn-making property and high-order processability. Further, from the above-mentioned latent crimpable conjugate fiber, a polyester fabric having a sufficient stretch performance and an appearance with little texture and defects such as elasticity and stiffness can be obtained.

The polyester latent crimpable composite of the present invention is a latent crimpable composite fiber in which two types of polyester components having different intrinsic viscosities are bonded in a side-by-side manner.
The polyester is preferably a polyester selected from at least one selected from the group consisting of polyethylene terephthalate, polyethylene naphthalate, polytrimethylene terephthalate, polytrimethylene naphthalate, polytetramethylene terephthalate, and polytetramethylene naphthalate. Among these, a polyester having polyethylene terephthalate as a main constituent is particularly preferable.

  In the present invention, the difference in intrinsic viscosity between a high viscosity polyester component (hereinafter sometimes referred to as a high viscosity component) and a low viscosity polyester component (hereinafter sometimes referred to as a low viscosity component) is 0.1 to 0. .4, more preferably in the range of 0.15 to 0.30. When the difference in intrinsic viscosity is less than 0.1, the difference in heat shrinkage between the two components tends to be insufficient, and the latent crimp performance as a composite fiber becomes insufficient. When the intrinsic viscosity difference exceeds 0.4, the quality of the resulting composite fiber is inferior due to the occurrence of poor bonding of the two components, or the bending, picking, swirling, etc. of the discharged polymer becoming severe. In addition, the productivity such as the yarn cutting rate and the yield in the yarn making process is also deteriorated. Moreover, it is preferable that the intrinsic viscosity of the low viscosity component is in the range of 0.4 to 0.7 and the intrinsic viscosity of the high viscosity component is in the range of 0.6 to 0.9 because the polymer discharge state becomes more stable.

Moreover, in the latent crimpable conjugate fiber of the present invention, it is important that the following requirements (a) to (d) are satisfied at the same time. It is possible to obtain a latent crimpable fiber that can moderately suppress the manifestation of fragility, obtain high-order processability, and obtain a fabric having sufficient stretch characteristics and excellent texture.
(A) Crimp rate after treatment with boiling water for 20 minutes under a load of 17.6 μN / dtex is 1.5% or more and less than 25% (b) Crimp after treatment with boiling water for 30 minutes under a load of 1.5 μN / dtex Rate is 30% or more and less than 50% (c) Strength is 1.5 cN / dtex or more (d) Elongation is 30% or more and 70% or less Hereinafter, each requirement will be described.

  (A) The crimp rate after treatment with boiling water for 20 minutes under a load of 17.6 μN / dtex is the restraint of the woven or knitted fabric when the fibers are woven and knitted into a fabric and then heat treated to reveal latent crimps. It is a scale representing the ability to develop crimp in a state where force is applied. If it is less than 1.5%, the ability to develop crimps to the fibers under the restraining force of the woven or knitted fabric is weak, so that it becomes difficult to impart good stretch performance and texture to the fabric. On the other hand, when it is 25% or more, the crimp of the fiber becomes too strong, and the texture of the fabric becomes too hard. The crimp rate is preferably 1.5% or more and 10% or less.

  (B) The crimp rate after 30 minutes of boiling water treatment under a load of 1.5 μN / dtex is that the fiber is treated with a different load after boiling water treatment with a low load that is almost free from the state where the yarn is wound as a drawn yarn. This is a method for comparing the crimp expansion and contraction of the yarn, and represents the general latent crimp performance, and at the same time, the absolute value of the measured value obtained is large, so the crimp already manifested in the raw yarn (drawn yarn state) It is also effective as a measure to know the rate. If this crimp ratio value is less than 30%, the crimping ability of the fiber is small, and it becomes difficult to impart good stretch performance and texture to the fabric. On the other hand, if it is 50% or more, the crimp of the fiber becomes too strong, and the texture of the fabric becomes hard. At the same time, the manifestation of the crimp of the raw yarn before the heat treatment is strong and it is difficult to handle in the higher processing step. Absent.

  In the present invention, as described above, the crimping rate is measured using two types of measurement methods with different loads during boiling water treatment, and a latent crimped yarn falling within a predetermined range is obtained by both measurement methods. is important. Thereby, the function at the time of making a fabric, a texture, and high-order workability can be made compatible.

  (C) When the strength is less than 1.5 cN / dtex, the fiber is easily broken in the process of turning, twisting and weaving, and the tear strength of the fabric is also weakened. In particular, when the fibers are thick and thin, the strength tends to be low. In the case of a drawn yarn having no thickness, 2.5 cN / dtex or more is preferable. When the strength is high, there is a tendency that the texture becomes hard, but there is no restriction that the strength should not be particularly higher. However, when yarn is made from polyester, there is a limit to the increase in strength, and it should be set within a range where stable production is possible.

  (D) When the elongation is less than 30%, the fabric is liable to have a dyeing defect and a defect in the form due to the influence of the fiber in the process of turning, twisting and weaving, and in the fiber drawing process. One to several of the multifilaments break and the tip of the breakage tends to become fluff, causing thread breakage and fabric defects in the processing step. On the other hand, when the elongation exceeds 70%, it is difficult to keep the strength and shrinkage ratio of the fibers moderate. The elongation is preferably 30% or more and 55% or less.

  In the present invention, the high viscosity polyester component is preferably a polyester copolymerized with isophthalic acid in an amount of 5% to 15%, more preferably 8% to 15%, particularly a polyethylene terephthalate polyester. If it is in this copolymerization rate range, the heat shrink property as a high viscosity component necessary for the present invention can be expressed. From this viewpoint, the low-viscosity polyester component is preferably a polyester that is substantially not copolymerized with isophthalic acid.

  In the present invention, the low-viscosity polyester component is measured in a chloroform solution in which the content of a metal element having a true specific gravity of 5.0 or more is 0 to 10 ppm by weight and the concentration is 20 mg / L and the optical path length is 1 cm. It is preferable that the polyester contains 0.1 to 10 ppm by weight of an organic compound color matching agent having a maximum absorption wavelength in the range of 540 to 600 nm in the visible light absorption spectrum in the 380 to 780 nm region. The polyester as described above, containing a color adjusting agent, exhibits a specific orientation and crystallization characteristics when it is spun and stretched using the low-viscosity component of the composite fiber, and is an object of the present invention. Latent crimped fibers can be easily obtained.

  More specifically, the present inventors have found that the following effects are obtained when the polyester is used as a low viscosity component. That is, the low-viscosity component shrinks appropriately during heat treatment under a low load, so that the difference in shrinkage rate from the high-shrinkage component does not become too large, thereby suppressing the manifestation of crimping at the stage of yarn production, especially in the drawing stage. The handling property in the processing process is improved. On the other hand, at the time of heat treatment under a high load, the shrinkage rate of the low-viscosity component is lower, the shrinkage difference from the high-viscosity component is larger, and a strong crimp is developed. This leads to the development of high crimps under a binding force such as a woven or knitted fabric, and a fabric having a good texture and excellent stretch performance can be obtained.

  Therefore, in the low viscosity component, when the content of the metal element having a true specific gravity of 5.0 or more is more than 0 to 10 ppm by weight, the above effect cannot be obtained. In particular, when the low-viscosity component contains an antimony compound, the fiber tends to crystallize even during heat treatment under a low load, and the shrinkage rate tends to be low, which increases the difference in shrinkage rate from the high-viscosity component. Shrinkage is strongly expressed. As a result, under such a low load, crimping in the drawn yarn state becomes obvious, and handling in a high-order processing step becomes difficult.

  In the present invention, the metal element having a true specific gravity of 5.0 or more is derived from a metal compound usually contained in a catalyst, a metal color adjuster, a matting agent, etc. contained in a polyester. Specifically, antimony, germanium, manganese, cobalt, cerium, tin, zinc, lead, cadmium and the like are applicable. On the other hand, titanium, aluminum, calcium, magnesium, sodium, potassium, and the like do not correspond to metals having a true specific gravity of 5.0 or more.

  In the present invention, the low-viscosity polyester component is a polyester obtained by polycondensation of an aromatic dicarboxylate ester in the presence of a catalyst containing a titanium compound component and a phosphorus compound. A titanium alkoxide represented by the general formula (I) and a titanium alkoxide represented by the following general formula (I) were reacted with an aromatic polycarboxylic acid represented by the following general formula (II) or an anhydride thereof. It is a component containing at least one selected from the group consisting of products, and the phosphorus compound is preferably a compound represented by the following general formula (III). As a result, due to the synergistic effect of the polyester obtained by polycondensation using the above specific catalyst and the color adjusting agent, the orientation and crystallization characteristics in the fiber formation stage show unique behavior, and heat treatment under low load. It has been found that there is a function of suppressing excessive low shrinkage of the low-viscosity component at the time, and the above-described effect appears more remarkably.

（上記式中、Ｒ^１、Ｒ^２、Ｒ^３及びＲ^４はそれぞれ同一若しくは異なって、アルキル基又はフェニル基を示し、ｍは１〜４の整数を示し、かつｍが２、３又は４の場合、２個、３個又は４個のＲ^２及びＲ^３は、それぞれ同一であっても異なっていてもどちらでもよい。）

(In the above formula, R ¹ , R ² , R ³ and R ⁴ are the same or different and each represents an alkyl group or a phenyl group, m represents an integer of 1 to 4, and m is 2, 3 or 4) In this case, 2, 3 or 4 R ² and R ³ may be the same or different from each other.)

（上記式中、ｎは２〜４の整数を表わす）

(In the above formula, n represents an integer of 2 to 4)

  Here, the titanium alkoxide represented by the general formula (I) specifically includes tetraisopropoxy titanium, tetrapropoxy titanium, tetra-n-butoxy titanium, tetraethoxy titanium, tetraphenoxy titanium, octaalkyl trititanate, And hexaalkyl dititanate are preferably used.

  The aromatic polyvalent carboxylic acid represented by the general formula (II) to be reacted with the titanium alkoxide of the present invention or an anhydride thereof includes phthalic acid, trimellitic acid, hemimellitic acid, pyromellitic acid, and these Anhydrides are preferably used.

  When the titanium alkoxide is reacted with an aromatic polyvalent carboxylic acid or an anhydride thereof, a part or all of the aromatic polyvalent carboxylic acid or an anhydride thereof is dissolved in a solvent, and the titanium alkoxide is added to the mixed solution. It is carried out by dripping and heating at a temperature of 0-200 ° C. for at least 30 minutes, preferably at a temperature of 30-150 ° C. for 40-90 minutes. There is no restriction | limiting in particular about the reaction pressure in this case, A normal pressure is enough. As the solvent for dissolving the aromatic polyvalent carboxylic acid or its anhydride, any of ethanol, ethylene glycol, trimethylene glycol, tetramethylene glycol, benzene, xylene and the like can be used as desired.

  Here, the reaction molar ratio between the titanium alkoxide and the aromatic polyvalent carboxylic acid or its anhydride is not particularly limited, but if the proportion of the titanium alkoxide is too high, the color tone of the resulting polyester deteriorates or the softening point. In contrast, if the proportion of titanium alkoxide is too low, the polycondensation reaction may not proceed easily. For this reason, it is preferable that the reaction molar ratio of the titanium alkoxide and the aromatic polyvalent carboxylic acid or its anhydride is in the range of 2/1 to 2/5.

  The catalyst system for polycondensation used in the present invention comprises the above titanium compound component and a phosphorus compound represented by the following general formula (III), and consists essentially of an unreacted mixture of both. It is.

（上記式中、Ｒ^５、Ｒ^６及びＲ^７は、同一又は異なって炭素数原子数１〜４のアルキル基を示し、Ｘは、−ＣＨ_２−又は―ＣＨ（Ｙ）を示す（Ｙは、ベンゼン環を示す）。）

(In the above formula, R ⁵ , R ⁶ and R ⁷ are the same or different and each represents an alkyl group having 1 to 4 carbon atoms, X represents —CH ₂ — or —CH (Y) (Y represents , Represents a benzene ring).)

  As the phosphorus compound (phosphonate compound) of the above general formula (III), carbomethoxymethanephosphonic acid, carboethoxymethanephosphonic acid, carbopropoxymethanephosphonic acid, carbobutoxymethanephosphonic acid, carbomethoxyphenylmethanephosphonic acid, carboethoxyphenyl It is preferably selected from dimethyl esters, diethyl esters, dipropyl esters, dibutyl esters and the like of phosphonic acid derivatives such as methanephosphonic acid, carboprotoxyphenyl methanephosphonic acid, carbobutoxyphenyl methanephosphonic acid and the like.

  The above phosphonate compound has a relatively slow reaction time with the titanium compound compared to the phosphorus compound that is usually used as a stabilizer, so the duration of the catalytic activity of the titanium compound during the reaction is long. The amount of the titanium compound added to the polyester can be reduced. Further, even when a large amount of stabilizer is added to the catalyst system containing the phosphorus compound of the general formula (III), the thermal stability of the resulting polyester is not lowered and the color tone is not deteriorated.

In the present invention, the catalyst containing the titanium compound component and the phosphorus compound preferably satisfies the following mathematical formulas (5) and (6).
1 ≦ P / Ti ≦ 15 (5)
10 ≦ P + Ti ≦ 100 (6)
Here, (P / Ti) is preferably 2 or more and 15 or less, and more preferably 10 or less. When (P / Ti) is less than 1, the hue of the polyester tends to be yellowish, while when it exceeds 15, the polycondensation reactivity of the polyester tends to decrease.

  Further, (Ti + P) is more preferably 20 or more and 70 or less. When (Ti + P) is less than 10, the productivity in the spinning process tends to decrease. On the other hand, when it exceeds 100, a small amount of foreign matter due to the catalyst tends to be generated, which is not preferable.

  In the above formula, a suitable amount of Ti is about 2 to 15 mmol%. The polyester polymer used in the present invention is a polymer obtained by polycondensation of an aromatic dicarboxylate ester in the presence of a catalyst containing the above titanium compound component and a phosphorus compound. The aromatic dicarboxylate ester is preferably a diester composed of an aromatic dicarboxylic acid and an aliphatic glycol.

  Here, the aromatic dicarboxylic acid is preferably terephthalic acid. More specifically, it is preferable that terephthalic acid accounts for 70 mol% or more based on the total aromatic dicarboxylic acid, and further, the terephthalic acid accounts for 80 mol% or more based on the total aromatic dicarboxylic acid. It is preferable. Examples of preferable aromatic dicarboxylic acids other than terephthalic acid include phthalic acid, isophthalic acid, naphthalenedicarboxylic acid, diphenyldicarboxylic acid, diphenoxyethanedicarboxylic acid, and the like.

  The other aliphatic glycol is preferably alkylene glycol, and for example, ethylene glycol, trimethylene glycol, propylene glycol, tetramethylene glycol, neopentyl glycol, hexanemethylene glycol, and dodecamethylene glycol can be used. In particular, ethylene glycol is preferable.

  In the present invention, as the low-viscosity component, the above-mentioned true specific gravity is 5.0 or less, in particular, the polyester containing no polyantimony compound is used. There are also few features that there is little discharge disturbance and fewer yarn breaks and poor quality.

  In addition, as described above, the polyester contains an organic compound color adjuster in an amount of 0.1 to 10 ppm by weight based on the total weight. Preferred for expression. When the content of the color adjusting agent is less than 0.1 ppm by weight, the yellowishness of the latent crimpable fiber becomes strong, and when used in combination with the above catalyst, the low level of forming side-by-side yarn is low. Since the viscosity component shifts in a direction in which it does not easily shrink due to heat treatment under a low load, the shrinkage difference from the high viscosity component becomes too large, and the manifestation of crimp becomes too strong, which is not preferable. On the other hand, when the content of the organic compound color adjusting agent exceeds 10 ppm by weight with respect to the total weight, the lightness is weakened and the blackness becomes strong in appearance, and the low viscosity component tends to shrink due to heat treatment under a low load. Because of the shift, the shrinkage difference from the high-viscosity component becomes small, and the desired texture and stretch performance cannot be obtained for the fabric. From the above viewpoint, the content of the color adjusting agent is more preferably in the range of 0.3 ppm to 9 ppm by weight.

  The organic color adjusting agent is an organic compound having a maximum absorption wavelength in a visible light absorption spectrum of 380 to 780 nm measured in a chloroform solution having a concentration of 20 mg / L and an optical path length of 1 cm in a range of 540 to 600 nm. It is a system color adjusting agent. When the maximum absorption wavelength is less than 540 nm, the redness of the latent crimpable fiber to be obtained becomes strong, and when it exceeds 600 nm, the blueness of the latent crimpable fiber to be obtained becomes strong. The range of the maximum absorption wavelength is more preferably in the range of 550 to 590 nm.

In the present invention, the organic compound color adjusting agent satisfies the following formulas (1) to (4) in which the ratio of the absorbance at each wavelength below to the absorbance at the maximum absorption wavelength satisfies all of the following formulas (1) to (4). It is preferable that
0.00 ≦ A ₄₀₀ / A _max ≦ 0.20 (1)
0.10 ≦ A ₅₀₀ / A _max ≦ 0.70 (2)
0.55 ≦ A ₆₀₀ / A _max ≦ 1.00 (3)
0.00 ≦ A ₇₀₀ / A _max ≦ 0.05 (4)
[In the above formula, A ₄₀₀ , A ₅₀₀ , A ₆₀₀ and A ₇₀₀ are the absorbance in the visible light absorption spectrum at 400 nm, 500 nm, 600 nm and 700 nm, respectively, and A _max is the absorbance in the visible light absorption spectrum at the maximum absorption wavelength. To express. ]

  Furthermore, in the above-described color adjusting agent, a blue color adjusting agent and a purple color adjusting agent are used in a weight ratio of 90:10 to 40:60, or a blue color adjusting agent and a red or orange color adjusting agent are used. It is preferable to use the colorant in a weight ratio of 98: 2 to 80:20. Here, the blue color adjusting agent is expressed as “Blue” among commercially available color adjusting agents. Specifically, the maximum absorption wavelength in the visible light spectrum in the solution is 580. It is about ˜620 nm. Similarly, the purple color adjusting agent is described as “Violet” among commercially available color adjusting agents. Specifically, the maximum absorption wavelength in the visible light absorption spectrum in the solution is 560 to 600. The one at about 580 nm is shown. The red color adjusting agent is described as “Red” among commercially available color adjusting agents. Specifically, the maximum absorption wavelength in the visible light absorption spectrum in the solution is about 480 to 520 nm. It is what. The orange-based color adjusting agent is one that is indicated as “Orange” among commercially available color adjusting agents.

  As these color adjusters, oil-soluble dyes are particularly preferable. Specific examples of the color adjusters include C.I. I. Solvent Blue 11, C.I. I. Solvent Blue 25, C.I. I. Solvent Blue 35, C.I. I. Solvent Blue 36, C.I. I. Solvent Blue 45 (Telasol Blue RLS), C.I. I. Solvent Blue 55, C.I. I. Solvent Blue 63, C.I. I. Solvent Blue 78, C.I. I. Solvent Blue 83, C.I. I. Solvent Blue 87, C.I. I. Solvent Blue 94 and the like. Examples of purple color adjusters include C.I. I. Solvent Violet 8, C.I. I. Solvent Violet 13, C.I. I. Solvent Violet 14, C.I. I. Solvent Violet 21, C.I. I. Solvent Violet 27, C.I. I. Solvent Violet 28, C.I. I. SolventViolet 36 etc. are mentioned. Examples of red color adjusters include C.I. I. Solvent Red 24, C.I. I. Solvent Red 25, C.I. I. Solvent Red 27, C.I. I. Solvent Red 30, C.I. I. Solvent Red 49, C.I. I. Solvent Red 52, C.I. I. Solvent Red 100, C.I. I. Solvent Red 109, C.I. I. Solvent Red 111, C.I. I. Solvent Red 121, C.I. I. Solvent Red 135, C.I. I. Solvent Red 168, C.I. I. Solvent Red 179 etc. are illustrated. Examples of orange color adjusters include C.I. I. Solvent Orange 60 etc. are mentioned.

Here, when a blue color modifier and a purple color modifier are used in combination, if the weight ratio of the blue color modifier is larger than the weight ratio of 90:10, the color a ^* value of the resulting polyester monofilament becomes small. When the color ratio is blue and the weight ratio of the blue color adjuster is smaller than 40:60, the color a ^* value increases and the color red is exhibited. Similarly, when a blue color modifier and a red or orange color modifier are used in combination, when the weight ratio of the blue color modifier is larger than the weight ratio 98: 2, the color a ^* value of the resulting polyester monofilament is If the weight ratio of the blue color adjusting agent is smaller than 80:20, the color a ^* value increases and a red color is exhibited, which is not preferable. The color adjusting agent is a combination of a blue color adjusting agent and a purple color adjusting agent in a weight ratio of 80:20 to 50:50, or a blue color adjusting agent and a red or orange color adjusting agent. More preferably, the weight ratio is in the range of 95: 5 to 90:10.

  The cross-sectional shape of the latent crimpable fiber of the present invention is a side-by-side type, thereby exhibiting latent crimp performance. In order to obtain the cross-sectional shape of the latent crimpable fiber of the present invention, a spinneret described in JP-A No. 2000-144518 may be used.

  Next, the bonding area ratio (high viscosity component / low viscosity component) of the two types of polyester is suitably in the range of 40/60 to 60/40, more preferably 55/45 to 45/55. . When the area ratio of the high-viscosity component exceeds 60, the latent crimped composite fiber obtained tends to have a lower potential crimpability. On the other hand, when the area ratio of the low-viscosity component exceeds 60, the latent crimp There exists a tendency for the intensity | strength of a shrinkage | conjugation composite fiber to become low or to increase fluff.

  Moreover, when the hollow part which occupies the area of 0.5 to 15% with respect to the total cross-sectional area, more preferably 1 to 10% is provided in the cross section of the latent crimped conjugate fiber of the present invention, the polymer discharge state becomes more stable. Furthermore, since the fiber is lightened, it has a positive effect on the texture of elasticity and stiffness. When the hollow ratio exceeds 15%, bonding failure such as hollow breakage may occur.

Furthermore, in the present invention, by setting the latent crimped fibers to fibers having a fine difference in the yarn length direction, it is possible to obtain a fabric having a texture of the eyelashes and a natural appearance.
In addition, the total fineness of the latent crimped conjugate fiber of the present invention is preferably in the range of 30 to 250 dtex and the single yarn fineness is in the range of 2 to 15 dtex from the viewpoints of workability and practicality in apparel use.

The latent crimped composite fiber of the present invention described above is obtained by drying two types of polyethylene terephthalate-based polyesters having different intrinsic viscosities obtained by the above-described method, respectively, using two conventional extruders (screw extruder) ) And melted in a normal composite spinning equipment equipped with a known side-by-side type composite spinneret (in the case of hollow composite fibers, a spinneret having a hollow-forming discharge hole is used). It can be manufactured by combining the flow, cooling and solidifying, applying an oil agent, taking up the spinning, and drawing. At this time, the yarn is taken up and once taken up as an undrawn yarn, and then drawn separately, or after drawing up the yarn, it may be drawn continuously without being taken up once. The melt spinning temperature is preferably in the range of 270 to 295 ° C. from the viewpoint of spinning stability. The spinning take-up speed and the draw ratio are appropriately set so that the strength of the latent crimped conjugate fiber is in the range of 1.5 to 5.0 cN / dtex and the elongation is in the range of 30 to 70%. The stretching preheating temperature is preferably 80 to 100 ° C.
As described above, as a method for forming a latent crimped composite fiber having a fine difference in the yarn length direction, a method of spot-drawing an undrawn yarn at a natural drawing ratio or less is preferably employed.

  In the present invention, before forming a fabric such as a woven or knitted fabric, twisting the latent crimped conjugate fiber at 100 to 5000 T / m, preferably 300 to 3000 T / m, emphasizes the crimp, It is preferable from the viewpoint that a firm texture can be easily obtained.

  The latent crimpable conjugate fiber of the present invention is made into a fabric such as a woven or knitted fabric, and heat treatment such as refining and dyeing is performed to reveal crimps, and a fabric with excellent texture can be obtained. At this time, it is more preferable in terms of texture that the stretch ratio of the fabric by the spandex method is 20% or more.

Hereinafter, the present invention will be described more specifically with reference to examples. In addition, each item in an Example was measured with the following method.
(1) Intrinsic viscosity A dilute solution obtained by dissolving a polyester chip in orthochlorophenol at 100 ° C for 60 minutes was determined from a value measured at 35 ° C using an Ubbelohde viscometer.

(2) Crimp rate after treatment with boiling water for 20 minutes under a load of 17.6 μN / dtex (TC-2)
Using a measuring instrument, the latent crimpable fiber is wound around a cassette frame to make a cassette of about 3300 dtex. After making the case, a load of 0.00176 cN / dtex + 0.176 cN / dtex (2 mg / denier + 200 mg / denier) is applied to one end of the case, and the length L0 (cm) after 1 minute is measured. Subsequently, it is treated in boiling water at 100 ° C. for 20 minutes with the load of 0.176 cN / dtex (200 mg / denier) removed. After the boiling water treatment, the load of 0.00176 cN / dtex (2 mg / denier) is removed, and it is naturally dried in a free state for 24 hours. A load of 0.00176 cN / dtex + 0.176 cN / dtex (2 mg / denier + 200 mg / denier) is again applied to the naturally dried sample, and the length L1 (cm) after 1 minute is measured. Next, the load of 0.176 cN / dtex (200 mg / denier) was removed, the length L2 after 1 minute was measured, and the crimp rate was calculated by the following formula. This measurement was performed 10 times and expressed as an average value.
TC-2 (%) = [(L1-L2) / L0] × 100
The measurement was performed 10 times and the average value was obtained.

(3) Crimp rate after treatment with boiling water for 30 minutes under a load of 1.5 μN / dtex (TC-0.2)
Using a measuring machine, the latent crimpable fiber is wound around a cassette frame to make a cassette of about 2200 dtex. After making the casserole, a load of 1.5 μN / dtex (1/6000 g / denier) is applied to one end of the casserole and the suspension is hung on a stand for 30 minutes, and then kept in this state and treated in boiling water for 30 minutes. Then, it is air-dried for 30 minutes, a 1/500 (g / denier) load is applied, and the length (a) is measured. Next, after removing the load of 1/500 (g / denier), the load of 1/20 (g / denier) is applied and the length (b) is measured. Then, the crimp rate was calculated by the following equation. This measurement was performed 10 times and expressed as an average value.
TC−0.2 (%) = [(ba) / b] × 100

(4) Bonding area ratio Latent crimped composite fiber is cut in the direction of the desired fiber cross section, and the cross section of the fiber is photographed with a commercially available microscope at a magnification of 750 times. The area occupied by each of the polyester cross sections was measured, and the ratio (high viscosity component occupied area / low viscosity component occupied area) was defined as “bonded area ratio” (average value of all measured single yarn cross sections).

(5) Hollow ratio (%) and variation in hollow ratio In the polyester composite fiber cross-sectional micrograph in the previous section, the hollow area (A) of each single yarn cross section and the area (B) surrounding the cross section are measured and calculated by the following formula: And the average value about the measured whole single yarn cross section was made into the hollow ratio (%).
Hollow ratio (%) = A / B × 100
Further, the variation rate of the measured value (standard deviation / average value × 100) was defined as the variation of the hollow rate.

(6) Qualitative analysis of metal component having a true specific gravity of 5.0 or more in the polymer:
A polymer sample is mixed with ammonium sulfate, sulfuric acid, nitric acid and perchloric acid, wet-decomposed at about 300 ° C for 9 hours, diluted with distilled water, qualitatively analyzed using a scientific ICP emission spectrometer (JY170 ULTRACE), The presence or absence of a metal element having a specific gravity of 5.0 or more was confirmed. About the metal element with which existence of 1 weight ppm or more was confirmed, the element content was shown.

(7) Titanium and phosphorus content soluble in polyester in the polymer:
The amount of titanium element soluble in polyester in the polymer and the amount of phosphorus element are obtained by heating and melting a granular polymer sample on an aluminum plate, and then creating a test molded body having a flat surface with a compression press machine. It was determined using Denki Kogyo Co., Ltd. Model 3270E). However, regarding the amount of titanium element in the polyester composition to which titanium oxide was added as a matting agent, the sample was dissolved in orthochlorophenol and then extracted with 0.5 N hydrochloric acid. The extract was quantified using a Hitachi Z-8100 atomic absorption spectrophotometer. Here, when dispersion of titanium oxide was confirmed in the extract after extraction with 0.5N hydrochloric acid, the titanium oxide particles were settled with a centrifuge, and only the supernatant was recovered by the gradient method. went. By these operations, even if the polyester composition contains titanium oxide, the titanium element soluble in the polyester can be quantified.

(8) Hue (L ^* value, a ^* value, b ^* value)
The polyester chip was melted at 285 ° C. under vacuum for 10 minutes, molded into an aluminum plate with a thickness of 3.0 ± 1.0 mm, immediately quenched in ice water, and the plate was dried at 140 ° C. for 1 hour. Crystallization was performed. Then, it placed on the white standard plate for color difference adjustment, and measured Hunter L ^* and b ^* of the plate surface using Minolta Co., Ltd. Hunter type color difference meter (CR-200 type). L ^* indicates lightness, and the larger the value, the higher the lightness, and b ^{* the} greater the value, the greater the degree of yellowing. Other detailed operations were performed according to JIS Z-8729.

(9) Strength / Elongation Measured according to JIS-L1013.

(10) Stretch rate Tensile tester with automatic recorder using latent crimpable fibers for warp and weft, woven and dyed in 2/2 twill structure and total cover factor 2000 by a conventional method Grab an initial load of 20 g using the and stretch it to a constant load of 1.5 kg at a tensile speed of 30 cm / min, then immediately return to the original position at the same speed and draw a load-extension curve. The stretch rate is expressed by the following equation when the extension distance is set to Lcm (up to 0.01 cm) immediately before returning to the original position at the same speed after extending to the above 1.5 kg constant load.
ST = [L / 10] × 100 (%)
This stretch rate was 20% or more.

(11) Fabric Texture and Appearance For a woven fabric obtained by weaving and dyeing a latent crimpable fiber into a 2/2 twill structure and a total cover factor 2000 by a conventional method, from the viewpoint of elasticity, stiffness, resilience, appearance (existence of defects), The ranking was made by three experts, “excellent”, “good”, and “bad”, and calculated from the average value.

(12) Handling in the processing process In the process of unwinding and rewinding the drawn yarn, and in the process of twisting, investigate the frequency of tension fluctuation caused by the yarn guide and the like due to the crimp of the yarn. The case where the number was small was defined as “good”, and the case where the number was large was defined as “bad”.

[Reference Example 1] Measurement of visible light absorption spectrum of color adjusting agent (color adjusting dye), preparation of color adjusting agent C.I. I. Solvent Blue 45 (manufactured by Clariant Japan) and C.I. I. Solvent Violet 36 (manufactured by Arimoto Chemical Co., Ltd.) was used as a chloroform solution with a weight ratio of 2: 1 and a concentration of 20 mg / L, and filled in a quartz cell with an optical path length of 1 cm. After filling, a visible light absorption spectrum in a visible light region of 380 to 780 nm was measured using a Hitachi spectrophotometer U-3010 type. Moreover, the ratio of the light absorbency in each wavelength of 400, 500, 600, and 700 nm with respect to the maximum absorption wavelength and the light absorbency in the wavelength was measured.
As a result, the maximum absorption wavelength in the visible light region was 580 nm, and the absorbance ratio at each wavelength was 0.10 at 400 nm, 0.41 at 500 nm, 0.76 at 600 nm, and 0.00 at 700 nm. .

[Reference Example 2] Synthesis of Titanium Catalyst A 1/2 mole of tetrabutoxytitanium with respect to trimellitic anhydride was added to an ethylene glycol solution (0.2% by weight) of trimellitic anhydride at 80 ° C under normal pressure in air. The reaction was continued for 60 minutes. Thereafter, it was cooled to room temperature, and the produced catalyst was recrystallized with 10 times the amount of acetone. The precipitate was filtered through filter paper and dried at 100 ° C. for 2 hours to obtain the target compound. This is designated as titanium catalyst A.

[Example 1]
-Manufacture of polyester chip of low viscosity component In a mixture of 100 parts of dimethyl terephthalate and 70 parts of ethylene glycol, 0.016 part of titanium catalyst A prepared in Reference Example 2 was charged into a SUS container capable of pressure reaction. The ester exchange reaction was performed while increasing the pressure from 140 ° C. to 240 ° C. under a pressure of 0.07 MPa, and then 0.023 part of triethylphosphonoacetate was added to complete the ester exchange reaction. Thereafter, 1.5 parts of a 20% ethylene glycol slurry of titanium oxide and 0.2 part of a 0.1 wt% ethylene glycol solution of a color adjusting agent prepared in Reference Example 1 were added to the reaction product, and the mixture was transferred to a polymerization vessel. The temperature was raised to 0 ° C., and a polycondensation reaction was performed in a high vacuum of 30 Pa or less to obtain a polyester composition. Furthermore, it was made into a chip according to a conventional method. The obtained polyester had an intrinsic viscosity of 0.43, a diethylene glycol content of 0.7% by weight, a color L ^* of 72, and a b ^* of 2.

・ Manufacture of polyester chip with high viscosity component 0.038 part of manganese acetate tetrahydrate was added to a mixture of 90 parts of dimethyl terephthalate and 55 parts of ethylene glycol, and transesterification was carried out while raising the temperature from 140 ° C to 240 ° C It was. After completion of the transesterification reaction, 8.6 parts of isophthalic acid was added and held for 20 minutes, and then 0.025 part of trimethyl phosphate, 0.045 part of antimony trioxide, and 1.5 part of 20% ethylene glycol slurry of titanium oxide were added. In addition, it was transferred to a polymerization vessel, and a polyester was obtained by performing a polycondensation reaction in a high vacuum of 30 Pa or less while raising the temperature to 290 ° C. Furthermore, it was made into a chip according to a conventional method. The obtained polyester had an intrinsic viscosity of 0.64, a diethylene glycol content of 0.7% by weight, a color L ^* of 71, and a b ^* of 5.

-Manufacture of latent crimpable composite fiber After drying the above-mentioned polyester chip having an intrinsic viscosity of 0.43 and polyester obtained by copolymerizing 10 mol% of isophthalic acid having an intrinsic viscosity of 0.63 by a conventional method, two melts It is introduced into a compound spinning machine equipped with an extruder (screw extruder), melted, introduced into a compound spinning pack equipped in a spin block maintained at 280 ° C., and two polymer streams are pasted at a compound spinneret. The combined weight ratio is 50/50, which is a side-by-side type (fiber cross-section with a hollowness of 1%), discharged while being combined, cooled and solidified, applied with oil, and taken up at a speed of 1450 m / min. 291 dtex / 24 filaments of undrawn yarn was obtained. While drawing the undrawn yarn at a preheating temperature of 90 ° C. and a draw ratio of 2.64 times, it was heat-set at 230 ° C. with a non-contact heater and wound up at 600 m / min, and a polyester latent crimp of 110 dtex / 24 filaments A functional composite fiber was obtained.
This latent crimpable fiber was used as a warp and a weft, twisted to a twist number of S1200 T / m according to a conventional method, and then woven and dyed into a 2/2 twill structure and a total cover factor 2000 to obtain a woven fabric.

  In this example, the spinning and drawing processes can be produced stably with few troubles such as yarn breakage. As shown in Table 2, the crimp characteristics of the latent crimpable fiber are low and high. Each was good. As shown in Table 1, the stretch ratio in the spandex method of the woven fabric is 29%, which is a sufficient value, and the texture is rich and firm, and the manifestation of crimp in the drawn yarn state Was weak, no particular problem occurred when unraveled and handled, and no defects of the fabric were found.

[Examples 2 to 4, Comparative Example 1]
The same procedure as in Example 1 was conducted except that the spinning speed, the draw ratio, and the heat setting temperature were changed as shown in Table 2 and the physical properties were changed. As a result, in Examples 2 to 4, the process of spinning and stretching can be produced stably with few troubles such as yarn breakage, and as is clear from Table 2, the stretch rate, texture, appearance, and processing steps of the fabric. As a result, all of the handling properties of were satisfied.
On the other hand, in Comparative Example 1, the elongation was low, troubles such as fuzz due to fiber breakage or partial breakage occurred frequently in the processing step, and the handleability was poor. In addition, because of this, the fiber had many defects and the appearance was not good.

[Example 5]
After obtaining an undrawn yarn in the same manner as in Example 1, a preheating temperature of 78 ° C. and a draw ratio of 2.4 are applied to the undrawn yarn while bending the yarn guide with two yarn guides to change the tension. While being stretched by a factor of 2, it was heat-set at 170 ° C. with a contact heater and wound up at 600 m / min to obtain 120 dtex / 24 filaments of polyester latent crimpable thick patch composite fiber. This was twisted, woven and dyed in the same manner as in Example 1 to obtain a woven fabric. In this example, troubles such as yarn breakage can be stably produced especially in the spinning and drawing processes, and as can be seen from Table 2, the stretch rate, texture, appearance, and handleability in the processing process of the fabric are improved. All the results were satisfactory.

[Examples 6 and 7]
The same procedure as in Example 1 was performed except that the fineness and the number of filaments of the latent crimpable conjugate fiber were 56 dtex / 12 filaments and 220 dtex / 48 filaments. In any of these examples, troubles such as yarn breakage can be stably produced in the spinning and drawing processes, and as can be seen from Table 2, the stretch rate, texture, appearance, and handleability in the processing process of the fabric. It became the result which satisfied all.

[Comparative Example 2]
As the low-viscosity polyester, except that antimony trioxide (Sb ₂ O ₃ ) was used as a polymerization catalyst, dimethyl terephthalate and ethylene glycol were polycondensed by a conventional method to obtain a polyester having an intrinsic viscosity of 0.43. Same as Example 1. In this example, the low-viscosity component is reduced too much by heat treatment under a low load and the difference in shrinkage from the high-viscosity component is increased, showing high crimping and the manifestation of crimping is too strong at the drawn yarn stage, Tension fluctuation during unwinding and twisting was large, and handling was poor. In addition, because of this, the fiber had many defects and the appearance was not good.

[Comparative Example 3]
The same procedure as in Example 1 was performed except that the intrinsic viscosity of the low-viscosity polyester was 0.55 and the difference in intrinsic viscosity from the high-viscosity polyester was 0.08. In this example, since the difference in intrinsic viscosity between the two types of polyester constituting the side-by-side fiber is small, the occurrence of crimp is weak in both heat treatment under low load and high load, and the stretch rate of the fabric is low. , It became a texture lacking resilience.

[Comparative Example 4]
The same procedure as in Example 1 was performed except that the color adjusting agent prepared in Reference Example 1 was not added to the low viscosity polyester. In this example, since there is no interaction between the catalyst containing the titanium compound and the phosphorus compound, the low viscosity component becomes too low in shrinkage by heat treatment under a low load, and the shrinkage difference from the high viscosity component becomes large, resulting in high crimping. In addition, the manifestation of crimping was too strong at the stage of the drawn yarn, the fluctuation in tension during unwinding and twisting was large, and the handleability was poor. In addition, because of this, the fiber had many defects and the appearance was not good.

  According to the present invention, it is possible to provide a polyester latent crimpable conjugate fiber excellent in yarn-making property and high-order processability. Further, from the above-mentioned latent crimpable conjugate fiber, a polyester fabric having a sufficient stretch performance and an appearance with little texture and defects such as elasticity and stiffness can be obtained. For this reason, the polyester latent crimpable conjugate fiber of the present invention is not only excellent in the productivity of the fiber and the fabric comprising the same, but also can produce a product with high added value from the fiber, and its industrial value. Is extremely high.

Claims (11)

A latent crimpable composite fiber in which two types of polyester components having different intrinsic viscosities are bonded to each other in a side-by-side type, wherein the difference in intrinsic viscosity between the high-viscosity polyester component and the low-viscosity polyester component is 0.1 to 0. A polyester latent crimpable conjugate fiber having a range of 4 and simultaneously satisfying the following requirements (a) to (d):
(A) Crimp rate after treatment with boiling water for 20 minutes under a load of 17.6 μN / dtex is 1.5% or more and less than 25% (b) Crimp after treatment with boiling water for 30 minutes under a load of 1.5 μN / dtex (C) Strength is 1.5 cN / dtex or more (d) Elongation is 30% or more and 70% or less   The polyester latent crimpable composite fiber according to claim 1, wherein the high-viscosity polyester component is a polyester obtained by copolymerizing isophthalic acid in an amount of 5% to 15%.   The low-viscosity polyester component has a metal element content of true specific gravity of 5.0 or more of 0 to 10 ppm by weight and is visible in a 380 to 780 nm region measured in a chloroform solution having a concentration of 20 mg / L and an optical path length of 1 cm. The polyester latent crimpable conjugate fiber according to claim 1 or 2, which is a polyester containing 0.1 to 10 ppm by weight of an organic compound color-matching agent having a maximum absorption wavelength in the range of 540 to 600 nm in the light absorption spectrum. The organic compound type color adjusting agent is an organic compound type color adjusting agent satisfying all of the following formulas (1) to (4), wherein the ratio of the absorbance at each wavelength below to the absorbance at the maximum absorption wavelength is satisfied. Polyester latent crimpable composite fiber.
0.00 ≦ A ₄₀₀ / A _max ≦ 0.20 (1)
0.10 ≦ A ₅₀₀ / A _max ≦ 0.70 (2)
0.55 ≦ A ₆₀₀ / A _max ≦ 1.00 (3)
0.00 ≦ A ₇₀₀ / A _max ≦ 0.05 (4)
[In the above formula, A ₄₀₀ , A ₅₀₀ , A ₆₀₀ and A ₇₀₀ are the absorbance in the visible light absorption spectrum at 400 nm, 500 nm, 600 nm and 700 nm, respectively, and A _max is the absorbance in the visible light absorption spectrum at the maximum absorption wavelength. To express. ]   The polyester latent material according to any one of claims 1 to 4, wherein the low-viscosity polyester component is a polyester obtained by polycondensation of an aromatic dicarboxylate ester in the presence of a catalyst containing a titanium compound component and a phosphorus compound. Crimpable composite fiber. The titanium alkoxide represented by the following general formula (I), the titanium alkoxide represented by the following general formula (I), and the aromatic polyvalent carboxylic acid represented by the following general formula (II) or an anhydride thereof 6. The polyester latent crimpable composite fiber according to claim 5, wherein the polyester latent crimpable conjugate fiber is a component containing at least one selected from the group consisting of products obtained by reacting with the above, and the phosphorus compound is a compound represented by the general formula (III).

(In the above formula, R ¹ , R ² , R ³ and R ⁴ are the same or different and each represents an alkyl group or a phenyl group, m represents an integer of 1 to 4, and m is 2, 3 or 4) In this case, 2, 3 or 4 R ² and R ³ may be the same or different from each other.)

(In the above formula, n represents an integer of 2 to 4)

(In the above formula, R ⁵ , R ⁶ and R ⁷ are the same or different and each represents an alkyl group having 1 to 4 carbon atoms, X represents —CH ₂ — or —CH (Y) (Y represents , Represents a benzene ring).) The polyester latent crimpable conjugate fiber according to any one of claims 3 to 6, wherein a molar ratio of a titanium metal element and a phosphorus element contained in the polyester satisfies the following mathematical formulas (5) and (6).
1 ≦ P / Ti ≦ 15 (5)
10 ≦ P + Ti ≦ 100 (6)
[In the above formula, P represents the concentration of the phosphorus element contained in the polyester composition (mmol%), Ti represents the concentration of the titanium metal element soluble in the polyester contained in the polyester composition (mmol%)). To express. ]   The polyester latent crimpable conjugate fiber according to any one of claims 1 to 7, wherein a bonding weight ratio of two kinds of polyesters (high viscosity polyester component / low viscosity polyester component) is 40/60 to 60/40.   The polyester latent crimpable conjugate fiber according to any one of claims 1 to 8, which has a fine difference in the yarn length direction of the conjugate fiber.   The polyester latent crimpable conjugate fiber according to any one of claims 1 to 9, wherein a hollow portion occupying an area of 0.5 to 15% with respect to the entire cross-sectional area is present in an arbitrary cross section of the conjugate fiber.   A woven or knitted fabric which is a woven or knitted fabric obtained by weaving and knitting the polyester latent crimpable conjugate fiber according to any one of claims 1 to 10, and having a stretch rate of 20% or more.