JPH06235120A - Polyester hollow fiber of high color development - Google Patents

Abstract

(57) [Summary] [Structure] A modified polyester polymer having an intrinsic viscosity (IV) of 0.64 or more obtained by copolymerizing an isophthalic acid component containing a metal sulfonate group and a polyalkylene glycol component is used. A polyester hollow having a high color-forming property, characterized in that the cross-section has a triangular or circular shape and has a triangular hollow portion at the center of the fiber cross section, and the thickness of the non-hollow portion satisfies the following formula: fiber. Wall thickness of non-hollow part (micron) ≧ 2.1 × d ^0.5 [where d = fiber fineness (denier)] [Effect] In addition to high color development that has never been seen, lightweight and excellent heat retention, In addition, it has a dry refreshing feel, sharpness and unique gloss that are not available in conventional materials, so it is highly valuable as a new material that is differentiated. Further, since it has high strength, the fiber cross section is unlikely to be crushed at the time of forming a knitted fabric, and a high quality product can be obtained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hollow polyester fiber having a high coloring property. More specifically, as a material for clothing, especially as a material for sports clothing, it has higher coloring than ever before, is lightweight, has excellent heat retention, and has a dry refreshing feeling,
The present invention relates to a high-quality polyester hollow fiber having good sharpness, high strength, and a fiber cross-section that does not easily collapse.

[0002]

2. Description of the Related Art Polyester fibers are widely used for general clothing because of their excellent properties such as mechanical properties, chemical properties, easy care and gloss. In particular, recently, it has attracted attention as a material for sports clothing and is used in various sports fields. Recent sports garments are required to have high color development and vividness due to diversification of needs and individuality, and some technologies have been developed and products are being sold. A basic dye-dyeable polyester is well known as a polymer having excellent color developability. As a basic dye-dyeable polyester, there has been known a polyester obtained by copolymerizing an isophthalic acid component having a metal sulfonate group, for example, 5-sodium sulfoisophthalic acid component, in Japanese Patent Publication No. 34-10497. However, in order to raise the color development to a satisfactory level, this product has an isophthalic acid component having a metal sulfonate group (hereinafter abbreviated as S component).
Must be a large amount of copolymerized. A polymer obtained by copolymerizing a large amount of S component has a high melt viscosity in the case of a polymer having a degree of polymerization required as a fiber due to the thickening effect of the S component,
It made spinning difficult. Therefore, in order to spin a polymer obtained by copolymerizing a large amount of S component by a usual method, it is necessary to lower the degree of polymerization of the polymer in order to reduce the melt viscosity to a range where it can be normally spun. However, as a result, there are drawbacks that the yarn strength is lowered, the yarn-forming property and the ability to pass through high-order processes are lowered, and the use is limited. Further, the copolymerization of a large amount of the S component also causes a decrease in the alkali resistance of the yarn and a decrease in the light resistance of the dyed product, which also limits the use of the obtained yarn. In particular, materials for sports clothing are required to have higher yarn strength and higher light resistance than products for general clothing.

[0003] Further, as one of the needs, it has been desired to reduce the weight of clothes. Particularly, in the case of sports clothes, there is a strong demand for weight reduction in view of easiness of exercise, and for winter clothes, heat retention is maintained. Is desired. As a means to measure the weight of clothing, it is possible to some extent by increasing the bulkiness of the yarn or devising the structure of the woven or knitted fabric, but it is necessary to reduce the weight of the fiber itself to measure the weight further. There is. Hollow fibers, which are apparently lightweight, are used as one of the means. Hollow fibers have been known for a long time. For example, in Japanese Patent Publication No. 42-2928, the hollow ratio is 5
A method for producing 0% or less hollow fibers is disclosed, and many other patent publications disclose hollow fibers and methods for producing hollow fibers.

Further, a technique of hollow fiber made of a polymer in which S component is copolymerized is disclosed in JP-A-59-211659. However, the hollow fiber of the technique is presumed to have low yarn strength and low spinnability and passability through higher-order processes due to the above-mentioned reasons. As disclosed in the publication, staple fibers are mixed with other fibers. It is used for a limited number of purposes. Further, a technique of a hollow fiber made of a polyester dyeable with a cationic dye is disclosed in Japanese Patent Laid-Open No. 4-289219, and the hollow fiber according to the technique contains a special copolymerization component and a special non-reactive component in the polyester. By adding it, the specified yarn characteristics are satisfied.

As mentioned above, there are some known hollow fiber techniques and techniques using special polymers for the hollow fibers. However, they have high coloring properties, are lightweight, have excellent heat retention, and have high strength. The reality is that high-quality polyester hollow fibers whose cross-section is difficult to be crushed have not been obtained.

[0006]

DISCLOSURE OF THE INVENTION The object of the present invention is to provide a high-quality polyester hollow fiber having high color development, light weight, excellent heat retaining property, high strength and crush-proof fiber cross section as described above. To do.

[0007]

The above-mentioned object of the present invention is to provide an isophthalic acid component containing a metal sulfonate group in an amount of 0.7 to 2.4 mol% and a molecular weight of 90 to 6000 with respect to the total dicarboxylic acid component. It is formed of a modified polyester having an intrinsic viscosity (IV) of 0.64 or more obtained by copolymerizing an alkylene glycol component in an amount of 0.2 to 10% by weight with respect to polyester, and the outer shape of the cross section of the fiber is triangular or circular, and It has a triangular hollow part in the center of the fiber cross section,
This can be achieved by a polyester hollow fiber having a high color-forming property, wherein the wall thickness of the non-hollow portion satisfies the following formula and the hollow ratio of the hollow portion is 15 to 50%. Wall thickness of non-hollow part (micron) ≧ 2.1 × d ^0.5 [where d = fiber fineness (denier)]

The present invention will be described in detail below. The polyester hollow fiber of the present invention has an isophthalic acid component containing a metal sulfonate group of 0.7 relative to the total dicarboxylic acid component.
.About.2.4 mol% and a polyalkylene glycol component having a molecular weight of 90 to 6000 (hereinafter abbreviated as "G component") is copolymerized in an amount of 0.2 to 10% by weight with respect to the polyester.
V) needs to be formed of a modified polyester having a value of 0.64 or more.

The modified polyester has higher yarn strength than that obtained by copolymerizing a large amount of S component to enhance the dyeability.
It shows good color development and light resistance to a basic dye.

The S component is a compound represented by the following formula, specifically dimethyl (5-sodiumsulfo) isophthalate, bis-2-hydroxyethyl (5-sodiumsulfo) isophthalate, bis-4-. Hydroxybutyl (5-sodium sulfo) isophthalate, dimethyl (5-lithium sulfo) isophthalate and the like.

[0011]

[Chemical 1] (However, in the formula, M represents an alkali metal such as Na, Li, and K, and A and A ′ are hydrogen, an alkyl group, or — (CH ₂ ).
It indicates _n OH, n is a 2 or more an integer) preferably S component, dimethyl (5-sodium sulfo) isophthalate, bis-2-hydroxyethyl (5-sodium sulfo) isophthalate. It is necessary to copolymerize the S component with 0.7 to 2.4 mol% with respect to the modified polyester acid component. When the copolymerization amount is less than 0.7 mol%, the dyeability and color development of the fiber with the basic dye are unsatisfactory,
If it exceeds 2.4 mol%, the melt viscosity becomes remarkably large, and therefore, in melt spinning, proper filtration cannot be performed, and an undrawn yarn having good yarn characteristics cannot be obtained. As a result, the yarn strength is also reduced.

The G component has a molecular weight of 90 to 6000.
Need to be. G with a molecular weight of less than 90
In order to copolymerize the components in an amount that satisfies the light resistance,
The dyeing and coloring properties of the fiber are insufficient, and the modified polyester has a low melting point due to its small molecular weight, resulting in poor high-order processability of the fiber.

On the other hand, the G component having a molecular weight of more than 6000 is difficult to be uniformly copolymerized in the modified polyester. Therefore, in order to copolymerize the obtained fiber in an amount satisfying the dyeing property and the color forming property, light resistance is required. Will be dissatisfied with. In addition, there are drawbacks such that the oxidative decomposition resistance of the modified polyester is lowered and the anti-frosting property of the obtained fabric is lowered. The preferred G component has a molecular weight of 100 to 4000.
And more preferably 100 to 1200.

A typical example of the G component having a molecular weight of 90 to 6000 is HO- (CH ₂ -CH ₂ -O) _m R
_{-O- (CH 2 -CH 2 -O)} n H ( wherein R is a straight chain of 3 to 20 carbon atoms, cyclic, divalent aliphatic hydrocarbon group having a side chain, a phenylene group, biphenylene group, Divalent aromatic hydrocarbon group such as naphthalene group, m and n are the same or different integers and 1 ≦ m + n ≦ 100), glycol, bisphenol A-ethylene oxide adduct and polyalkylene represented by the following formula Examples include glycol. _{A (C n H 2 n O} ) m H ( wherein A is _C e H _{2e + 1} O or OH, e is 1 to 1
0, n are 2-5, m shows the integer of 2-65. )

As the G component, polyalkylene glycol is preferable. This is more advantageous than other G components for obtaining a modified polyester having a degree of polymerization required to obtain fibers having good yarn characteristics, because the polyalkylene glycol has a thickening effect larger than that of other G components. It depends. And as polyalkylene glycol, OH at both ends
More preferred is a polyethylene glycol having a group. This is because the shorter the alkylene oxide unit and the more randomly copolymerized glycol, the greater the effect of improving color development and the effect of reducing viscosity.

The amount of the G component copolymerized must be in the range of 0.2 to 10% by weight based on the modified polyester. When the amount of the G component copolymerized is less than 0.2% by weight, the color development of the modified polyester fiber is unsatisfactory, and when it exceeds 10% by weight, the light resistance and oxidative decomposition resistance of the dyed fabric are deteriorated.

The intrinsic viscosity of the modified polyester fiber in the present invention is required to be 0.64 or more. If the intrinsic viscosity is less than 0.64, the yarn strength is not at a satisfactory level and it is difficult to increase the hollow ratio of the hollow fiber. However, if the intrinsic viscosity is too high, the melt viscosity during melt spinning becomes too high and spinning becomes difficult. Therefore, the intrinsic viscosity is preferably 0.88 or less.

The modified polyester of the present invention contains well-known additives such as matting agents, antioxidants, optical brighteners, flame retardants, and ultraviolet absorbers within the range that does not impair the effects of the present invention. It may have been done.

Further, the polyester hollow fiber of the present invention must have a triangular or circular cross-section. If the outer shape of the cross section of the fiber is extremely irregular, yarn breakage easily occurs during spinning, and yarn breakage or fluffing easily occurs during drawing. Note that the triangle means a so-called “rice ball type” in which the corners of the triangle are rounded as shown in FIG. 4, and the sides of the triangle are not recessed inward. Further, the circular shape does not necessarily have to be a perfect circle, and may be a substantially perfect circle,
Specifically, it is a circle or an ellipse and the difference between the long diameter and the short diameter is within 10%, or the distance R1 to the point on the outer circumference farthest from the yarn center of gravity and on the outer circumference closest to the yarn center of gravity. In the present invention, the relationship of the distance R2 to the point is [(R1-R2
) / R1] × 100 ≦ 10. The present invention also includes a shape intermediate between the triangle and the circle described above.

Further, the polyester hollow fiber of the present invention is required to have a triangular hollow portion substantially at the center of the fiber cross section. That is, it means that the hollow portion does not exist eccentrically. The fact that there is a hollow part makes it lighter by that amount,
The weight of the woven / knitted fabric can be reduced.

Further, even when the modified polyester used in the present invention is fiberized into a normal circular cross-section yarn or a modified cross-section yarn, the above-mentioned good properties, that is, yarn strength, spinnability, high-order process passing property, color development property, resistance to Although it is possible to improve the alkalinity and light resistance, the sharpness and gloss can be improved by using a special hollow fiber.

Although the factor that can improve the sharpness and gloss is not clear, when the hollow fiber is exposed to light, it is transmitted to the hollow portion, and the light is reflected again on the inner wall of the triangular hollow portion to give gloss. It seems to be increasing. Further, since the hollow portion is located at the center of the fiber and the hollow portion has a triangular shape, the hollow portion is less likely to be crushed, that is, the hollow ratio is not lowered at the time of stretching and the higher-order processing step. Generally, in the manufacture of hollow fibers and their higher-order processing steps, the hollow fibers are subjected to yarn contact pressure with rollers, frictional force in guides or other external force,
When pressure is applied to the fibers from the side direction, the fiber cross section is crushed into an elliptical shape or a flat shape, and the hollow ratio decreases. This phenomenon is more likely to occur in hollow fibers having a higher hollow ratio. In addition, when the hollow ratio exceeds a certain level, it tends to occur when the outer shape of the fiber and the hollow portion are circular. Further, if the hollow portion is not located at the center of the fiber and is eccentric, that is, if the hollow portion is partially present, it tends to occur. On the other hand, the polyester hollow fiber of the present invention has a triangular hollow portion in the central portion of the fiber cross section as described above, and thus is difficult to be crushed.

The triangular shape of the hollow portion of the hollow fiber of the present invention will be described with reference to FIG. Let three apexes of a triangular shape be a, b and c, respectively, and let three sides of a triangle connecting three points be straight lines be ab, bc and ca. A perpendicular line cd is drawn from the point c to the side ab, and an intersection point with the hollow wall on the extension of the perpendicular line cd is defined as e. A perpendicular line is drawn from the point a and the point b to the side bc and the side ca, respectively, and points f, g, h, and i are determined as shown in the drawing. The hollow portion of the hollow fiber of the present invention has a triangular shape as a whole, preferably an equilateral triangle, but may be a rice ball shape as shown in FIG. 3, and the shape is as follows. (1) The lengths of the line segments ab, bc, and ca on the sides are preferably equal, but may change within 20%.

(2) Line segment ag / line segment af, line segment bi / line segment bh, line segment ce / line segment cd have respective values of 1.0 to
The range of 1.3 is preferable, and 1.0-1.
It is in the range of 2.

The area occupied by the hollow portion in the fiber cross section of the hollow fiber of the present invention, that is, the hollow rate, must be in the range of 15 to 50%. When the hollow ratio is less than 15%, the effect of reducing the weight of clothing and the effect of retaining heat are small. The warmth of the woven or knitted fabric can be increased to a certain extent by using a structure that contains air between fibers or tissues as described above, but if a structure that contains too much air is used, the air warmed by body temperature will be Convection occurs and heat retention decreases. Since the hollow fiber encloses air in the fiber itself, there is no convection and heat retention can be improved. The higher the hollowness, the greater the effect of weight reduction and the effect of heat retention, which is preferable.However, if the hollowness of the fiber is too high, the fiber cross-section is likely to be crushed in the high-order processing step, and the fiber becomes less The hollow ratio cannot be maintained, and the fiber cross section is likely to be crushed even when the clothing is worn. Therefore, the hollow ratio must be 50% or less. It is more preferably 20 to 40% from the viewpoints of the effect of weight reduction, the effect of heat retention, and the crushability of the fiber cross section during wearing.

Furthermore, it is necessary that the thinnest part of the hollow fiber of the present invention has a wall thickness that satisfies the following formula in the non-hollow part. Wall thickness (micron) ≧ 2.1 × d ^0.5 (denier) For example, in the case of 3 denier fiber, it is necessary that the thickness is 3.6 microns or more. The wall thickness of the non-hollow part is determined by the fineness of the hollow fiber, the hollow ratio and the shape of the hollow part, but in any case, it is necessary to prevent the collapse of the fiber cross section by the wall thickness satisfying the above formula. .

Further, in the fiber of the present invention, the presence or absence of fluff at the stage of the raw yarn, that is, the fluff of the yarn which is drawn and wound, is greatly related to the quality of the high-order processability, and the influence thereof is the conventional polyester fiber. Big compared to. Therefore, fluff number of yarns wound is preferably not more than 0.20 particles / 10 ⁴ m, more preferably at most 0.10 pieces / 10 ⁴ m, 0.05 pieces / 10 It is more preferably ⁴ m or less.

The polyester hollow fiber of the present invention is obtained by melt spinning the modified polyester of the present invention from a spinneret having a three-slit type polymer discharge hole shown in FIG. 2 to give an oil agent to obtain an undrawn yarn. It can be obtained after winding once or by subsequently stretching. On this occasion,
Forced cooling of melt-spun yarn is 3-15 cm below the spinneret surface
It is preferable to start the blowing of the cooling air at the above distance because the variation in the hollow ratio can be reduced. When further stretching, using a hot roll-hot roll stretching machine,
A method of preheating with a first hot roll to 75 to 100 ° C. and stretching with a second hot roll is preferable in order to reduce generation of fluff. The temperature of the second hot roll may be appropriately set so as to match the target shrinkage characteristic of the yarn to be obtained. The cross section of the resulting fiber is almost equivalent to that shown in FIG.

The polyester hollow fiber of the present invention can be utilized not only as a material for clothing, but also as a material for construction of industrial materials such as car seats. Among the materials for clothing, it is particularly effective as a material for sports clothing.

As described above, by copolymerizing the S component and the G component to form a modified hollow fiber which is composed of a modified polyester having an intrinsic viscosity of a certain level or more and is specified, it is possible to obtain a high hollow fiber which is not available in conventional hollow fibers. It is possible to provide a high-quality fiber that has a color developability, a dry refreshing feeling, good clarity, high strength, and a fiber cross-section that is hard to be crushed, is lightweight, and has excellent heat retention. Therefore, the polyester hollow fiber according to the present invention can be effectively utilized not only as a material for clothing but also as a material for building construction materials.

[0031]

The present invention will be described in more detail with reference to the following examples. The physical properties in the examples were measured as follows.

A. Glycol component in polymer After amine decomposition of the polymer, quantitative analysis was performed using gas chromatography or liquid chromatography.

B. Glossiness After adjusting the reference value using a standard glossy plate of magnesium oxide under the conditions of 45 degrees of irradiation and 44 degrees of light reception using an automatic colorimetric color difference meter manufactured by Suga Test Instruments, the sample was wound on an aluminum plate in the fiber axis direction. The glossiness was measured by irradiation and light reception.

C. Hollow ratio Calculated by the following formula from a cross-sectional photograph of the fiber. Hollow ratio (%) = (Cross-sectional area of hollow part / Cross-sectional area of fiber) × 1
00

D. Using a multi-fly counter F type manufactured by Toray Engineering Co., Ltd., five drawn yarns were run at about 400 m / min, each measuring 5 × 10 ⁴ m, and the number of fluffs was calculated from the total number counted. Fluff count (pieces / 10 ⁴ m) = (total number of counts / 25 × 10
⁴ m) x 10 ⁴

E. Intrinsic viscosity 0.8 g of modified polyester was dissolved in 10 cc of orthochlorophenol, and the solution was mixed with Ostwald viscometer to 2
It was measured and determined at 5 ° C.

F. It measured based on the blue scale at the time of photobleaching according to JIS-L1044 using a light resistance fade meter.

G. Dyeability Malachite Green (manufactured by Kanto Chemical Co., Inc.) 5% owf,
Acetic acid 0.5 g / l, sodium acetate 0.2 g / l, bath ratio 1:
It was determined by the dye exhaustion rate due to dyeing under the conditions of 100 and temperature 120 ° C. solvent water.

H. Coloring property A state in which the fabric is dyed by the above method so that the dye exhaustion rate is the same, and five or more fabrics are stacked by using an SM color computer (manufactured by Suga Test Instruments Co., Ltd.), and irradiation light is not transmitted. The L value was measured with. (The smaller the L value, the better the color developability.) Example 1 As a polymer, terephthalic acid (98.3 mol%) was used as an acid component.
And dimethyl-5-sodium sulfoisophthalic acid (1.
7 mol%), a polyester using ethylene glycol as a glycol component and a glycol shown in Table 1 (having an intrinsic viscosity adjusted to 0.68 to 0.70), and a spinning temperature of 295 ° C. After discharging from the die with 24 holes, cool it by applying cooling air at a speed of 25 m / min at a position 8 cm below the surface of the die so that the oil content with high smoothness becomes 1.0%. After applying while controlling, it was wound at a spinning speed of 1650 m / min.

The obtained undrawn yarn is preheated by a hot roll-hot roll drawing machine with the first hot roll set at 90 ° C., and the drawn yarn elongation is 3 with the second hot roll.
Heat treatment is performed at a second hot roll temperature of 143 ° C. while stretching at a stretching ratio of 5 ± 2%, and a winding speed is 800 m / min.
In this way, a hollow fiber yarn of 75 denier 24 filament was wound up. The obtained yarn was knitted into a circular knitted fabric. The cross section of the obtained fiber was the same as in FIG. 1 and the hollow portion was triangular and the center portion of the fiber was present. The thinnest portion had a wall thickness of 4.6 microns. The number of fluffs of the obtained fiber yarn was the same as that of Experiment No. in which polyalkylene glycol was not added.
Although a large number of No. 8 were generated, Experiment No. Other than 8, 0.10 pieces / 1
It was 0 ⁴ m or less. Moreover, the hollow ratio of each of the obtained fibers was in the range of 27 to 29%. Table 1 shows the tenacity, the color developability in a circular knitted fabric, the dyeability, and the light resistance of the obtained fiber.

[0041]

[Table 1] Experiment No. of the present invention. Nos. 1 to 7 have high yarn strength, are excellent in dyeability, color development, and light resistance, and have a dry refreshing feeling as a result of a sensory evaluation of the knitted fabric, and also have good sharpness,
It also had a unique luster.

Experiment No. In No. 8 (Comparative Example), the yarn strength was remarkably low, the number of fluffs was as large as 30/10 ⁴ m, and the color development and light resistance were not sufficient. Experiment No. 9 (Comparative example)
Has a low dyeing property, and the test No. Sample No. 10 (Comparative Example) had poor light resistance, many yarn breakages occurred during stretching, and uneven dyeing of the dyed knitted fabric.

Example 2 Experiment No. 1 of Example 1 A hollow fiber yarn having a changed hollow ratio was obtained in the same manner as in Example 1 except that the polymer of Example 6 was used and the die in which the inner diameter of the slit provided in the die discharge hole of FIG. 2 was changed. . The number of fluffs of the obtained yarn is 0.1
And a 0/10 ⁴ m or less, strength ranged from 286～295G.

Further, the thickness of the thinnest portion of the non-hollow portion is in the range of 3.4 to 6.0 μm, and the experiment No. No. 14 has a diameter of 3.7 μm and is an experiment No. 15 was the thinnest at 3.4 microns. The obtained hollow fiber yarn was evaluated according to Example 1. The light resistance was all 4.0 grade. The other evaluation results are shown in Table 2.

[0045]

[Table 2] Experiment No. 11 (comparative example) has a small hollow ratio and a small effect of lightness. In addition, the color developability was also slightly small. The thickness of the thinnest part (micron) of the part that is not hollow is
2.1 × 3 ^0.5 = Experiment No. less than 3.6 (micron)
In No. 15, the crushing of the fibers occurred frequently and the crushing degree was large, and the crushing of the fibers occurred frequently during knitting, and the hollow ratio in the knitted fabric was small. Experiment No. 1 of the present invention is advantageous in terms of lightness and shape retention of the fiber cross section in the post-processing. 12, 13, 14
The fibers can be effectively used.

Example 3 Experiment No. 1 of Example 1 Hollow fiber yarn was obtained in the same manner as in Example 1 except that polyester having a polymer composition of No. 6 and various intrinsic viscosities IV was changed, and a spinning temperature at which melt spinning was normally performed was obtained, and evaluated in accordance with Example 1. . Intrinsic viscosity IV
Experiment No. No. 16 has a low yarn strength and is not at a satisfactory level. Moreover, the number of yarn breakages during spinning was 5 times / ton, and the number of fluffs of the yarn was 3.4 k / 10 ⁴ m.

Experiment No. Nos. 17 to 20 had no problems in hollow ratio and strength. However, in Experiment No. Since No. 20 has a high melt viscosity during spinning, it is difficult to spin for a long time, which is not preferable in production. The other properties such as color developability, dyeability and light resistance were all satisfactory. The results are shown in Table 3.

[0048]

[Table 3] Example 4 Experiment No. 1 of Example 1. 6 of the polymer of FIG.
Hollow fiber yarns having different fiber cross-sections were obtained and evaluated according to Example 1 except that a die having a die discharge hole of b was used. The cross sections of the resulting fibers are shown in Figures 5a and 5b. The experimental results are shown in Experiment No. The results are shown in Table 4 in comparison with No. 6.

[0049]

[Table 4] Hollow fiber yarn having the trilobal outer shape shown in Fig. 5a (Experiment N
o. 21 (comparative example), hollow ratio of 17.2%), the number of yarn breakage during spinning was as high as 16 times / ton, and the occurrence of fluff during stretching was as high as 3.8 k / 10 ⁴ m, and the yarn breakage ratio was also high. It was as high as 13%.

The hollow fiber yarn having the eccentric hollow portion shown in FIG. 5B (Experiment No. 22 (comparative example) has a hollow ratio of 27.5.
However, when the knitted fabric was knitted, the change in the cross section was large and the fibers were crushed, and the hollow ratio was lowered to 19.2%.

Example 5 Experiment No. 1 of Example 1 6, the polymer of FIG.
Hollow fiber yarns in which the shapes of the hollow portions of the fibers were compared were obtained and evaluated according to Example 1 except that the die having the die discharge holes of 1 was used and the hollow ratio was adjusted to about 36%. The cross section of the obtained fiber is almost the same as the shape shown in FIGS. 1 and 5c. The experimental results are shown in Table 5.

[0052]

[Table 5] The hollow fiber yarn of which the shape of the hollow part is almost perfect as shown in FIG. 5c (Experiment No. 24 (Comparative Example)) had a hollow ratio of 36.5%, but the change in cross section was large when knitted. The fibers were crushed and the hollow ratio was reduced to 27.2%. Also,
In the knitted fabric, streaky unevenness was generated in the crushed portion of the fiber, and the quality of the knitted fabric was extremely poor.

The hollow fiber yarn of which the shape of the hollow portion shown in FIG. 1 is substantially triangular (Experiment No. 23 (invention), has a hollow ratio of 3).
Although the content was 6.2%, the fibers were not crushed even when knitted, and the hollow ratio was 34.4%, and the quality of the knitted fabric was good.

[0054]

EFFECT OF THE INVENTION The polyester hollow fiber of the present invention has a high color development which has never been obtained, is lightweight and has excellent heat retention, and has a dry refreshing feeling, good sharpness, high strength, and knitted fabric. The fiber cross section is difficult to collapse during formation, etc.
It is of high quality.

Since it has an excellent coloring property and its effect is remarkable, it is particularly suitable as a knit material for sports among the materials for clothing. The polyester hollow fiber of the present invention has a coloring property,
In addition to being lightweight and heat-retaining, it also possesses sharpness and unique luster that conventional materials do not have, so it is highly valuable as a new material that is differentiated.

[Brief description of drawings]

FIG. 1 is a fiber cross-sectional view showing an example of a polyester hollow fiber of the present invention.

FIG. 2 is a plan view showing a die discharge hole when manufacturing the polyester hollow fiber of FIG.

FIG. 3 is a model view of the polyester hollow fiber in FIG.

FIG. 4 is a fiber cross-sectional view showing an example other than FIG. 1 of the polyester hollow fiber of the present invention.

FIG. 5 is a fiber cross-sectional view of a polyester hollow fiber of a comparative example in the present invention.

FIG. 6 is a plan view showing a die discharge hole when manufacturing the polyester hollow fiber of FIG.

Claims (1)

[Claims] 1. An isophthalic acid component containing a metal sulfonate group is used in an amount of 0.7 to 2.4 mol% based on the total dicarboxylic acid component, and a polyalkylene glycol component having a molecular weight of 90 to 6000 is used in an amount of 0.2 to about 100%. It is formed of a modified polyester having an intrinsic viscosity (IV) of 10% by weight copolymerized of 0.64 or more, and the cross-section of the fiber has a triangular or circular outer shape, and a triangular hollow portion is formed at the center of the fiber cross-section. A polyester hollow fiber having a high color-forming property, characterized in that the wall thickness of the non-hollow part satisfies the following formula, and the hollow ratio of the hollow part is 15 to 50%. Wall thickness of non-hollow part (micron) ≧ 2.1 × d ^0.5 [where d = fiber fineness (denier)]