JPH10110328A - Polyester fiber excellent in see-through preventing property and production thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a polyester fiber having a se-through preventing property, capable of exhibiting an excellent see-through preventing property even in a thin cloth, and also stably produced industrially. SOLUTION: This polyester fiber having a see-through preventing property is a composite fiber obtained by arranging a polyester constituted by a main repeating unit of polyethylene terephthalate and containing 2.0-10.0wt.% anatase type titanium dioxide having <=10μm mean particle size of primary particles in a core and a polyester containing <2.0wt.% content of inorganic fine particles in a sheath. The fiber has a shape in which a cross section of the core is formed by three rhombi, a circumferential part of the sheath has a triangular cross section, three tips of one of the tips of three rhombi are connected at one point and the three tips of another one of the tips of the three rhombi are positioned in the direction of tips of the triangular cross section of the outer circumferential part of the sheath. The fiber is a thick and thin fiber having <=6.0% coefficient of variance CV, although the unevenness in the thickness of the overall fiber is expressed by >=0.7% mean deviation ratio.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polyester fiber having excellent see-through prevention properties and a method for producing the same.

[0002]

BACKGROUND OF THE INVENTION Polyesters are widely used as general clothing fibers because of their many excellent properties.
Particularly in sportswear such as tennis wear, swimwear, leotards, or in applications such as blouses, office uniforms, and white coats, a performance is required that does not show through even if it is thin. Inorganic fine particles such as titanium oxide have been added to impart a matting effect of irregularly reflecting light that is refracted on the fiber surface and enters the inside of the fiber.

[0003] However, in order to obtain a satisfactory see-through preventing effect in such a method, it is necessary to contain a large amount of titanium oxide. In addition to the false twisting process, weaving,
In the knitting process, abrasion of a yarn path guide, a roller surface, a reed, a knitting needle, and the like was promoted, and there were problems such as generation of a large number of fluffs and yarn breaks and an increase in the number of parts replacement.

In order to improve such disadvantages, Japanese Patent Publication No.
No. 17925, Japanese Patent Publication No. 63-17926, a core-sheath composite spinning is used in which the core component contains a large amount of titanium oxide, the titanium oxide of the sheath component is reduced, and the core / sheath portion is arranged concentrically to form a composite. A method has been proposed in which a fiber is used to enhance the light shielding property and to reduce abrasion of a guide, a leg, and the like in a twisting yarn, a weaving and knitting process, and the like. Although the problem of abrasion in the processing step described above is improved by the publication technique, light passing only through the sheath component is generated, and thus, there is no sufficient countermeasure in the see-through prevention. Furthermore, the effect of preventing see-through is imparted by mixing cotton, but the mixing ratio of cotton is large, and only a thick and firm texture is obtained.

[0005]

SUMMARY OF THE INVENTION The present invention is to provide an anti-sheer polyester fiber which exhibits excellent sheer-preventing properties even with a thin cloth and which can be manufactured industrially stably.

[0006]

Means for Solving the Problems In order to solve the above-mentioned problems, the present inventors have proposed a polyester fiber having a cross-sectional shape and optical properties and an anti-transparency property with respect to the content of an inorganic substance, and furthermore, have the following problems. As a result of detailed studies on passage stability and the like, the present invention has been reached.

That is, according to the present invention, an anatase type titanium dioxide whose main repeating unit is composed of polyethylene terephthalate and the average particle size of primary particles is 1.0 μm or less is 2.0 to 10.0% by weight. % Polyester fiber, wherein the fiber cross-section is a polygonal cross-section, characterized in that the fiber is a see-through-resistant fiber having excellent surface gloss characteristics, and the core has a main repeating unit made of polyethylene terephthalate. The average particle size of the primary particles is 1.0
anatase type titanium dioxide having a particle size of not more than 2.0 μm
A composite fiber in which a polyester containing 0.0% by weight is mainly composed of polyethylene terephthalate in a sheath portion and the content of inorganic fine particles is less than 2.0% by weight, A first aspect of the present invention is a first aspect of the present invention, which is an anti-sheer fiber having excellent surface gloss characteristics, wherein the outer peripheral section of the sheath is a polygonal section.

The refractive index of the polyester fiber is 1.6 to 1.
7 and the refractive index of other fiber materials (1.45-1.
6), and since polyester fibers are produced by a melt spinning method, the surface thereof is generally very smooth, so that the light reflectance on the fiber surface is large. In the present invention, the fiber cross-sectional shape is changed, and a polygonal cross-section having a flat portion on the surface, preferably a triangular or quadrangular cross-section, improves specular reflection characteristics, excellent fiber surface gloss characteristics, and additionally has light transmittance. Is greatly reduced, and the matting effect is promoted.

In particular, by adopting a triangular cross-sectional shape, the content of titanium oxide can be reduced to one-fourth or less in order to obtain the same transparent preventing effect as compared with a round cross-sectional shape, thereby impairing the manufacturing process permeability. Nonetheless, even if the blending ratio of cotton is reduced, the sheer-prevention property is improved, and a very soft texture as clothing can be obtained. At this time, the content of titanium oxide needs to be in the range of 2 to 10% by weight. If it exceeds 10% by weight, the dispersibility is reduced, and the filter material is clogged significantly during spinning, making it difficult to produce polyester fibers practically and industrially stably. in case of,
Even in the present invention, sufficient anti-transparency cannot be obtained.

[0010] In addition, in the present invention, preferably, a polyester to which a small amount of titanium oxide is added or to which kaolin having the same refractive index as that of polyester is added is disposed on the fiber surface, and the main repeating unit of the core component is polyethylene terephthalate. A core-sheath composite spun fiber comprising a polyester containing 2.0 to 10.0% by weight of an anatase type titanium dioxide having an average primary particle diameter of 1.0 μm or less which is composed of turret. In this way, a yarn path guide and a roller in a spinning process, a stretch twisting process, a false twisting process or a weaving or knitting process caused by titanium oxide present on the fiber surface.
Problems such as accelerated wear of the surface, reeds, knitting needles, and the like, and occurrence of fuzz and thread breakage are eliminated.

At this time, it is necessary that the outer peripheral section of the sheath is a polygonal cross section so as not to impair the see-through preventing property which is the object of the present invention. is there. Further, the composite ratio of the core is preferably 60% or more, and in order for the composite ratio of the core to be 60% or more without exposing the core to the fiber surface, the cross-sectional shape of the core is The cross section is formed from three diamonds,
The outer periphery of the sheath has a triangular cross section, and one vertex of the three diamonds of the core is connected at one point, and the other vertex of the three rhombs of the core is directed to each vertex of the triangular cross section of the outer periphery of the sheath. It is preferable that the shape is located at

By adopting such a shape, it is possible to prevent a remarkable decrease in the content of titanium oxide near the apex of the rhombus of the core, and at the same time to prevent the polyester component containing a large amount of titanium oxide from being exposed on the fiber surface. It is possible to arrange the core at a composite ratio of 60% or more. That is, since the content of titanium oxide near the apex of the rhombus of the core tends to decrease remarkably, the other apexes of the three rhombuses of the core are located in the respective vertex directions of the triangular cross section of the outer periphery of the sheath. It is preferable that the shape is formed. Furthermore, if the outer periphery of the sheath is a polygon having a triangular cross section or more, a sufficient flat surface cannot be secured, making it difficult to provide specular reflection characteristics.If the core component has a circular shape, the core component is exposed on the fiber surface. It is difficult to form a composite with a core ratio of 60% or more without performing the above. As the inorganic fine particles contained in the polyester of the sheath, inorganic fine particles such as kaolin can be used in addition to the same titanium dioxide as the core.

Further, the fiber of the present invention is preferably a thick and thin fiber having a large fineness and a fineness in the longitudinal direction of the fiber. This is because the plane of the large fineness portion is emphasized, and the specular reflection characteristics are improved, which is effective in improving the see-through prevention. Compared to natural fibers or synthetic fibers obtained by a method other than the melt spinning method, fibers obtained by the melt spinning method have a higher surface smoothness, and as a result, a waxy feeling including a unique slimy feeling is strong, and it is difficult to adapt to the skin However, the marbling-like sink-and-thin fiber solves these disadvantages. In other words, since it is a so-called partially different shrinkage mixed yarn in which the fineness changes in the longitudinal direction of the single fiber, the fabric obtained by the sink and thin yarn has a unique texture and also has the effect of improving the quality of the material. doing. Such a thick and thin yarn preferably has an average deviation rate of 0.7% or more and a variation coefficient CV of 6.0% or less, as a whole. That is, the average deviation rate of the thickness unevenness of the entire yarn is 0.7
%, The difference in fineness, the difference in dyeing density, and the difference in shrinkage characteristics between the thick part and the small part of each constituent fiber are sufficiently exhibited. When the average deviation rate is less than 0.7%, these characteristic differences are not exhibited, and a so-called plain yarn form is formed, and it is difficult to obtain a feeling effect and an improvement effect of prevention of see-through as a thick and thin yarn. Further, when the variation coefficient CV of the thickness unevenness of the entire yarn is 6.0% or more, there is a tendency that so-called slab-like unevenness in which the thick portion of each fiber is concentrated. In contrast to the marbling thick and thin fibers in which the thick portions of each fiber are dispersed, such slab-like thick and thin fibers are difficult to obtain a micro-different shrinkage form, and are unfavorable in feeling or quality.

The variation coefficient CV of the thickness unevenness is a value obtained by measuring a Worcester normal value at a yarn speed of 8 m / min using an EVENESTESTER KET-80C manufactured by Keisoku Kogyo Co., Ltd. This is an index indicating the magnitude of the deviation from the average value.

The fiber obtained in this manner is a transparent fiber having excellent surface gloss characteristics and a rate of decrease in the amount of transmitted light with respect to the amount of irradiated light of 30% or more. In addition, the measuring method of the reduction rate of the transmitted light quantity is based on the following method.

[Measuring method of reduction rate of transmitted light amount] Titanium oxide is 0.46 wt% in warp yarn with 50 denier and 18 filaments.
Polyethylene terephthalate yarn containing
Using this test cloth, undyed taffeta test cloth in which 80 test yarns of 75 denier and 36 filaments were punched per inch and 68 test yarns of 100 denier per inch were inserted into the weft, the illuminance was 15,000 to 16000. It was placed on a Lux fluorescent lamp, and the illuminance on the upper part of the test cloth was measured with an illuminometer and calculated by the following equation.

[0017]

(Equation 1)

Further, a second gist of the present invention is to provide an anatase type dioxide having an average primary particle diameter of 1.0 μm or less in the polymerization of polyester whose main repeating unit is composed of polyethylene terephthalate. Titanium was added as an ethylene glycol dispersion to the polyester polymer and polymerized in an amount of 2.0 to 10.0% by weight, and the obtained polymer was obtained from a spinneret having a multi-lobed cross-section spinning hole. A method for producing an anti-sheer fiber having excellent surface gloss characteristics, characterized by being melt-spun, and an average particle diameter of primary particles in the polymerization of a polyester whose main repeating unit is composed of polyethylene terephthalate. Of anatase type titanium dioxide having a particle size of 1.0 μm or less as an ethylene glycol dispersion was used in an amount of 2.0 to 10. 0% by weight, and polymerized. The obtained polymer was disposed on the core, and a polyester having a content of inorganic fine particles of less than 2.0% by weight was disposed on the sheath. Has a spinning hole that is a multi-lobed cross section,
Near the apex of each leaf, from a spinneret having a core spinning hole, a method for producing an anti-sheer fiber having excellent surface gloss characteristics characterized by melt spinning, and their surface gloss characteristics are excellent. This is a method for producing a see-through preventive fiber having excellent surface gloss characteristics by drawing an undrawn yarn of the see-through preventive fiber in two steps under conditions satisfying the following conditions to obtain a marbling thick and thin fiber.

TDR = MDR × (0.45 to 0.60) TDR = DR1 × DR2 DR1 = MDR × (0.40 to 0.55) HRT ≦ TC Tg ≦ HPT ≦ TC where TDR is total stretching Magnification, DR1 is the first draw ratio, DR2 is the second draw ratio, MDR is the maximum draw ratio of the undrawn yarn, HRT is the temperature (° C.) in the first draw, HP
T is the temperature (° C.) in the second drawing region, TC is the crystallization temperature (° C.) of the undrawn yarn, and Tg is the glass transition temperature (° C.) of the undrawn yarn.

A spinneret having a multi-lobal spinning hole is used as the spinneret having a polygonal outer peripheral surface of the fiber used in the present invention. In particular, to obtain a triangular cross section, the spinning hole should be 120
ＹY-shaped cross-section spinning holes protruding at three positions to be rotated at intervals are preferably used. The same applies to the cross-sectional shape of the sheath portion of the composite spinneret. The spinning hole of the core portion is formed by rotating the round hole at 120 ° intervals in the Y direction of the sheath portion to be rotated.
A spinneret located near the apex of the cross section is preferably used. Thus, the core section is formed of three rhombuses, the outer periphery of the sheath is a triangular cross section, one vertex of one of the three rhombuses of the core is connected at one point, and the other of the three rhombuses of the core is formed. May have a shape located in the direction of each vertex of the triangular cross section of the outer peripheral portion of the sheath.

In addition, in the present invention, it is more preferable that the flat surface of the thick fine portion is emphasized and the specular reflection is performed by performing a marbling thick anthine drawing that forms a random thick fine portion and a fine fine portion in the fiber axis direction. The properties are improved, which is effective for improving the see-through prevention. In the present invention, two-stage stretching is performed in order to form the large fine portion and the fine fine portion in a highly dispersed state. The heating temperature in the first-stage drawing is equal to or lower than the crystallization temperature of the undrawn yarn, and the draw ratio DR1 is MDR × (0.4
0 to 0.55), and set a lower value and stretch.

Since the utilization of MDR differs depending on the degree of crystallization and the degree of orientation of the undrawn yarn used, the residual elongation of the thick and thin yarn obtained by the first-stage drawing is 70 to 110%. It is desirable to set to. The sink-and-thin yarn obtained by the first-stage drawing is a yarn having a high shrinkage ratio and a large difference in fineness between the thick fineness portion and the fine fineness portion.

The sink-and-thin yarn obtained in the first-stage drawing is subjected to the second-stage drawing and the total draw ratio TDR is MDR × (0.
45 to 0.60) and additional stretching (that is, specifically, the range of DR2 is 1.00 to 1.20).
Is preferred. Then, heat treatment is performed at a temperature equal to or higher than the glass transition temperature and equal to or lower than the crystallization temperature, which is set so as to give a desired shrinkage ratio in the second-stage stretching zone. By the second-stage drawing, a sink-and-thin yarn in which the thick fine portion and the fine fine portion are randomly dispersed can be obtained.

[0024]

DETAILED DESCRIPTION OF THE INVENTION The titanium oxide used in the present invention must be an anatase type titanium dioxide from the viewpoint of hardness and dispersion stability in a dispersion medium such as water and ethylene glycol. The average particle size of the particles needs to be 1.0 μm or less. In the case of titanium oxide having a large primary particle size, clogging of the filter medium during spinning is remarkable, and it becomes difficult to produce polyester fibers practically stably on an industrial scale.

In the present invention, the polyester in which the main repeating unit is an ethylene terephthalate unit is a polyester having terephthalic acid or an ester-forming derivative thereof as a main acid component and ethylene glycol as a main alcohol component. It may be a copolymer of a conventionally known acid component or alcohol component.

Specific examples of the acid component include dicarboxylic acids such as adipic acid, isophthalic acid, naphthalenedicarboxylic acid, diphenyldicarboxylic acid, diphenylsulfondicarboxylic acid, sebacic acid and 1,4-cyclohexanedicarboxylic acid, and esters thereof. Derivatives, disulfonic acids containing a metal sulfonate group such as sodium 5-sodium sulfoisophthalate, 2-sodium sulfoisophthalic acid, sodium 1,8-dicarboxynaphthalene-3-sulfonate, or the like. Ester-forming derivatives, or potassium salts, lithium salts and the like of these compounds, and
Examples thereof include p-oxybenzoic acid, p-β-oxycarboxylic acids, and ester-forming derivatives thereof.

Specific examples of the alcohol component include:
Lower alkylene glycols such as propylene glycol and butylene glycol, 1,4-cyclohexanedimethanol, neopentyl glycol, 1,4-bis (β-oxyethoxy) benzene, bisphenol A Bisglycol ether and the like.

Further, as long as the polyester is substantially linear, a polycarboxylic acid such as trimellitic acid and pyromellitic acid, and a polyol such as pentaerythritol, trimethylolpropane and glycerin, or a monocarboxylic acid. A polymerization terminator such as hydric polyalkylene oxide and phenylacetic acid may be used.

Such a polyester can be synthesized by any known method. For example, in the case of polyethylene terephthalate, the esterification reaction between terephthalic acid and ethylene glycol is carried out directly, or the lower alkyl ester of terephthalic acid such as dimethyl terephthalate is transesterified with ethylene glycol. A general method is to synthesize glycerol ester of terephthalic acid and / or a low polymer thereof by reacting or adding ethylene oxide to terephthalic acid, and then subjecting the product to polycondensation by a conventional method. It is a target.

Further, in synthesizing the polyester of the present invention, a known catalyst, an antioxidant, a coloring inhibitor,
Ether bond by-product inhibitors, flame retardants, ultraviolet absorbers and the like can be used as appropriate.

The above-mentioned titanium dioxide can be added to the polyester at any stage before the polyester production reaction is completed.

The polymer obtained in this manner is formed into chips by a conventional method, dried, and passed through a known multi-lobal cross section spinning hole.
The cross-sectional shape is polygonal, and the spinning temperature is 280-290 ° C.
Melt spinning to about. After the discharged yarn is cooled and solidified, an oil agent is applied to obtain an undrawn yarn. The undrawn yarn thus obtained is subjected to ordinary drawing to obtain a drawn yarn. Alternatively, two-stage drawing for obtaining the above-mentioned thick and thin yarn is performed to obtain a marbling thick and thin drawn yarn.

Alternatively, a polyester containing inorganic fine particles of kaolin or titanium dioxide is used as the sheath polymer, and the above-mentioned polyester containing titanium dioxide is used as the core polymer. Among them, the outer peripheral section of the sheath has a spinning hole with a multi-lobal section,
An undrawn yarn is obtained by melt-spinning from a spinneret having a core spinning hole near each vertex of the multilobe. Specifically, the discharge hole of the core component is branched into three locations to be rotated at 120 ° intervals, and the outer periphery of the sheath portion is positioned at a position near a vertex of a Y-shaped cross-sectional shape forming a regular triangular cross-sectional shape. The melt composite spinning is performed at 280 to 290 ° C. using a spinneret in which the component round holes are located so that the core / sheath ratio becomes core / sheath = 3/1. By subjecting the composite spun undrawn yarn to normal drawing or thick and thin drawing, the see-through preventive fiber having excellent surface gloss characteristics of the present invention can be obtained.

[0034]

EXAMPLES Hereinafter, the present invention will be described specifically with reference to Examples. In the examples, parts and% mean parts by weight and% by weight, respectively. In the table, ◎, ×, Δ, and X indicate very good, good, slightly good, and poor, respectively. Indicates that

Example 1 100 parts of terephthalic acid and 52 parts of ethylene glycol were charged into an esterification tank and 4 kg
The esterification reaction was performed at 260 ° C. under a pressure of / cm 2. Subsequently, trimethyl phosphate, antimony trioxide, anatase type titanium dioxide having an average primary particle diameter of 0.3 μm were added to the obtained reaction product in an amount of 1.0%, 2.0%, 2.0%
Each as an ethylene glycol dispersion so that
It was transferred to a polymerization tank. A polycondensation reaction is carried out at 285 ° C. for a predetermined time under a high vacuum, and the intrinsic viscosity measured by an Ostwald viscometer at 25 ° C. in a 1: 1 mixed solvent of 1,1,2,2-tetrachloroethane and phenol. Was 0.68.

The polymer was formed into chips by a conventional method, dried, and melt-spun at 285 ° C. using a spinneret provided with 36 spinning holes having a Y-shaped triangular cross section. After the discharged yarn was cooled and solidified, an oil agent was applied, and a 180-denier MDR = 3.3 undrawn yarn was obtained at a take-up speed of 2000 m / min. The undrawn yarn is drawn at an upper draw ratio of 1.01, a lower draw ratio of 2.40, a first drawing temperature of 75 ° C., and a second drawing region temperature of 145 ° C. to give 75 denier and a breaking strength of 4.8 g /. d, A drawn yarn having a breaking elongation of 30%, a BWS of 7%, and a yarn spot average deviation rate of 0.4% was obtained. The undrawn yarn is stretched at an upper draw ratio of 1.65, a lower draw ratio of 1.01, a first drawing temperature of 110 ° C., and a second drawing region temperature of 120 ° C. to obtain 108 denier and a breaking strength of 2. 6 g / d, elongation at break 85%, BWS 17%, average deviation rate of thread spot 1.0
% And a yarn variation coefficient CV of 4.7% to obtain a marbling thick and thin drawn yarn. The obtained sink-and-thin yarn was woven, scoured, and heat-set at a fixed length to obtain a fabric. The rate of decrease in the amount of transmitted light was measured on the cloth thus obtained, and the texture was evaluated. The results are shown in Table 1.

Example 2 The amount of titanium diacid added to the polymer of Example 1 was changed to 4.0%, and the other conditions were the same as those in Example 1, except for spinning, elongation, knitting, and the like. Dyeing was performed to obtain a fabric. The results are shown in Table 1.

Example 3 100 parts of terephthalic acid and 52 parts of ethylene glycol were charged into an esterification tank, and 4 k
The esterification reaction was performed at 260 ° C. under a pressure of g / cm 2. Subsequently, trimethyl phosphate, antimony trioxide, anatase type titanium dioxide having an average primary particle diameter of 0.3 μm were added to the obtained reaction product in an amount of 1.0%, 2.0%, 4.0
% As an ethylene glycol dispersion, and transferred to a polymerization tank. A polycondensation reaction is carried out at 285 ° C. for a predetermined time under a high vacuum, and the intrinsic viscosity measured by an Ostwald viscometer at 25 ° C. in a 1: 1 mixed solvent of 1,1,2,2-tetrachloroethane and phenol. Was 0.68. Similarly, 100 parts of terephthalic acid, ethylene glycol
The esterification reaction was carried out at 260 ° C. under a pressure of 4 kg / cm 2. Subsequently, trimethyl phosphate, antimony trioxide, and kaolin were added to the resulting reaction product in ethylene glycol so as to be substantially 1.0%, 2.0%, and 0.1% with respect to the produced polyester. It was added as a dispersion and transferred to a polymerization tank. Perform polycondensation reaction at 285 ° C under high vacuum for a predetermined time,
A polymer having an intrinsic viscosity of 0.68 measured by an Ostwald viscometer at 25 ° C. in a 1: 1 mixed solvent of 1,1,2,2-tetrachloroethane and phenol was obtained.

These polymers are formed into chips by a conventional method.
After drying, the core component discharge spin hole of the core-in-sheath composite spinneret is branched into three locations to be rotated at intervals of 120 °, and the apex of the discharge hole of the Y-shaped sheath portion forming a regular triangular cross-sectional shape. A spinneret provided with 30 discharge spinning holes in which a core component discharge round hole is located is used in the vicinity, a polymer containing 2% of titanium oxide is disposed on the core, and kaolin is contained in the sheath. Then, a polymer containing 0.1% was placed and melt-spun at 285 ° C. such that the core / sheath ratio became 3/1. After the discharge yarn is cooled and solidified, an oil agent is applied, and 2,000 m / mi
At a take-off speed of n, 150 denier, MDR = 3.3
Was obtained. The undrawn yarn is subjected to an upper draw ratio of 1.0.
1. Lower stretching ratio 2.40, first stretching temperature 75 ° C., second stretching zone temperature 145 ° C., 60 denier, breaking strength 4.8 g / d, breaking elongation 30%, BWS
A drawn yarn having a yarn spot average deviation rate of 0.4% and a yarn spot average deviation rate of 0.4% was obtained. The undrawn yarn was subjected to an upper draw ratio of 1.65, a lower draw ratio of 1.01, a first drawing temperature of 110 ° C., and a second drawing temperature of 12 ° C.
By stretching at 0 ° C., it is 90-denier, breaking strength 2.6 g / d, breaking elongation 85%, BWS 17%, yarn spot average deviation rate 1.0%, and yarn spot variation coefficient CV 5.6%. An and thin drawn yarn was obtained. The obtained thick and thin yarn was woven, scoured, and heat set at a fixed length to obtain a fabric. The rate of decrease in the amount of transmitted light was measured on the cloth thus obtained, and the texture was evaluated. The results are shown in Table 1.

Example 4 Trimethyl phosphate, antimony trioxide and anatase type diacid titanium were added to the sheath polymer of Example 3 in an amount of 1.0%, 2.0%, 0.5%, and otherwise, according to Example 2, spinning, drawing, knitting,
Dyeing was performed to obtain a fabric. The results are shown in Table 1.

Comparative Example 1-4 Content of Titanium Dioxide,
Examples 1 and 4 were carried out except that the fiber cross section was changed as described in Table 1. The results are shown in Table 1.

[0042]

[Table 1]

[0043]

The anti-sheer fiber of the present invention has a polygonal cross section, and is excellent in glossiness by improving the specular reflection characteristics of the fiber and matting effect by suppressing light transmission. Develops excellent sheer prevention properties.

[Brief description of the drawings]

FIG. 1 is a transmission microscope photograph showing a composite state of a cross section of an undrawn yarn of Example 3, with a magnification of 300 times.

FIG. 2 is a cross-sectional view showing a core component discharge port of a core-sheath composite spinneret used to obtain a fiber of Example 3.

FIG. 3 is a bottom view of the core component discharge port of FIG. 2;

FIG. 4 is a cross-sectional view showing a sheath component discharge port of a core-sheath composite spinneret used to obtain a fiber of Example 3.

FIG. 5 is a bottom view showing the sheath component ejection port of FIG. 4;

(Equation 1)

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI D01F 8/14 D01F 8/14 B

Claims (11)

[Claims] The main repeating unit is composed of polyethylene terephthalate, and the average primary particle size is 1.
2.0 μm or less of an anatase type titanium dioxide
Polyester fiber containing 10.0% by weight, wherein the fiber cross-section is a polygonal cross-section. 2. An anatase-type titanium dioxide in which a main repeating unit is composed of polyethylene terephthalate and whose primary particles have an average particle diameter of 1.0 μm or less is 2.0 to 10.0 weight%. % Of polyester, wherein the main repeating unit in the sheath is polyethylene terephthalate, and the content of the inorganic fine particles is less than 2.0% by weight. Has a polygonal cross section, and has excellent surface gloss characteristics. 3. The sheath outer peripheral section is a triangular section.
An anti-sheer fiber having excellent surface gloss characteristics as described. 4. The core section is formed of three diamonds,
The outer periphery of the sheath has a triangular cross-section, and one vertex of the three diamonds of the core is connected at one point, and the other vertex of the three diamonds of the core is directed to each vertex of the triangular cross-section of the outer periphery of the sheath. 4. The see-through preventing fiber having excellent surface gloss characteristics according to claim 2 or 3, which has a shape positioned as described above. 5. The see-through preventive fiber having excellent surface gloss characteristics according to claim 2, wherein the core is not exposed on the fiber surface, and the composite ratio of the core is 60% or more. 6. The anti-sheer fiber having excellent surface gloss characteristics according to any one of claims 1 to 5, which is a thick and thin fiber having a thick fineness and a fine fineness portion in the fiber longitudinal direction. 7. The variation in the thickness of the yarn as a whole is 0.7% or more in average deviation rate and the coefficient of variation CV is 6.0.
%. The anti-sheer fiber having excellent surface gloss characteristics according to claim 6. 8. The reduction rate of the transmitted light amount with respect to the irradiation light amount is 3
The transparent fiber having excellent surface gloss properties according to any one of claims 1 to 7, which exhibits 0% or more. 9. An ethylene glycol dispersion of an anatase type titanium dioxide having an average primary particle size of 1.0 μm or less in the polymerization of a polyester whose main repeating unit is composed of polyethylene terephthalate. And polymerizing it in an amount of 2.0 to 10.0% by weight with respect to the polyester polymer, and melt-spinning the obtained polymer from a spinneret having a multi-lobed cross-section spinning hole. Method for producing anti-sheer fiber having excellent surface gloss characteristics. 10. A dispersion of an anatase type titanium dioxide having an average primary particle diameter of 1.0 μm or less in an ethylene glycol dispersion during polymerization of a polyester whose main repeating unit is composed of polyethylene terephthalate. The polymer is added and polymerized so as to be 2.0 to 10.0% by weight with respect to the polyester polymer, and the obtained polymer is disposed in the core, and the content of the inorganic fine particles is less than 2.0% by weight. Polyester is arranged on the sheath, and the outer periphery of the sheath has a spinning hole with a multi-lobed cross-section, and melt spinning is performed from a spinneret having a core spinning hole near each vertex of the multi-lobal shape. A method for producing an anti-sheer fiber having excellent surface gloss characteristics. 11. The surface gloss of an undrawn yarn of a see-through preventing fiber having excellent surface gloss characteristics according to claim 9 or 10, which is drawn in two steps under conditions satisfying the following conditions to obtain a marbling thick and thin fiber. A method for producing a see-through preventing fiber having excellent characteristics. TDR = MDR × (0.45 to 0.60) TDR = DR1 × DR2 DR1 = MDR × (0.40 to 0.55) HRT ≦ TC Tg ≦ HPT ≦ TC where TDR is the total stretching ratio and DR1 Is the first draw ratio, DR2 is the second draw ratio, MDR is the maximum draw ratio of the undrawn yarn, HRT is the temperature (° C.) in the first draw, HP
T is the temperature (° C.) in the second drawing region, TC is the crystallization temperature (° C.) of the undrawn yarn, and Tg is the glass transition temperature (° C.) of the undrawn yarn.