JPH04136217A - Elliptical uneven cross-sectional polyester fiber - Google Patents

Abstract

PURPOSE:To provide the subject fiber having a specific cross-sectional shape, having excellent opaque property, dyeability, strength and luster and further having a soft hand touch by copolymerizing with a specific amount of a metal sulfonate group-containing isophthalic acid component and with a specified amount of a polyalkylene glycol component, adding a delustering agent to the copolymer and subsequently spinning the copolymer. CONSTITUTION:A modified polyester copolymerized with an isophthalic acid component having a metal sulfonate group in an amount of 0.7-2.4mol% based on all dicarboxylic acid components and with a polyalkylene glycol component having a mol.wt. of 90-6000 in an amount of 0.2-10wt.% and containing 1.3-8.0wt.% of a delustering agent, is melt-spun through a spinneret having extrusion holes each having a modified cross-sectional shape to form uneven cross-sectional shaped fibers which are characterized by follows; a long axis A at the longest line portion of the cross section of each fiber and a short axis B vertical to the long axis A are satisfied with the equation I; the cross section of the fiber has eight leaf portions which are positioned at both the ends of the axis A and on both the lateral sides of the axis A in mutually faced states; depressions are disposed between the leaves; the lengths C of both the side leaves are satisfied with the equation II; the lengths D between the depressions are satisfied with the equation III; when the longest line among lines between cross points of the line A with the lines B-D is 1, the other lines are 0.6-1.0.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention provides an anti-transparent material that has good dyeability, high yarn strength, excellent color development (deep color) and sharpness, and a milky color. The present invention relates to a polyester fiber with an elliptical uneven cross section suitable for high-grade woven and knitted fabrics, which has a novel texture that is shiny, soft, and uniquely smooth.

[Prior Art] Polyester fibers have excellent physical and chemical properties and are therefore widely used for clothing and industrial purposes. Particularly in the field of clothing, various fibers with irregular cross sections have been proposed and used to improve the quality of clothing. Among them, there are many disclosures of techniques related to multi-lobal cross-section fibers.

For example, Japanese Patent Application Laid-open No. 50-59524 proposes a polyester fiber with an oval cross section and four lobes suitable for use in fur-like pile fabrics (Fig. 3). It is stated that it is possible to produce pile fabrics that have a sticky feel, a pleasant luster, lower bending stiffness than circular fibers, good elasticity in the pile, and suppressed fibrillation. However, since there are four lobes and therefore four recesses, and the depth of the recesses is shallow, ordinary dyed woven or knitted fabrics do not have sufficient color development (depth of color) or clarity. In addition, although a smooth feeling was observed, it was still insufficient. When I say "smooth feeling" here, I mean a "smooth" feeling when you lightly touch the fabric, but a moderate "squeak" when you touch it further.
It is something that has.

Japanese Unexamined Patent Publication No. 57-29626 discloses that in order to obtain a polyester filament yarn having a texture similar to that of a latent crimp composite yarn or a woven fabric obtained from a knit yarn, Japanese Patent Application Laid-Open No. 57-29626 discloses that in order to obtain a polyester filament yarn that has a texture similar to that of a latent crimp composite yarn or a woven fabric obtained from a knitted yarn, A filament with an irregular cross section has been proposed, and the ratio of the diameter in the major axis direction to the diameter in the minor axis direction is 1.5 or more (FIG. 4).

Proposed examples of the filament include elliptical, cross-shaped flat, eyebrow-shaped, and slit-shaped flat shapes, all of which were knitted into a knitted fabric after being subjected to 50 to 2,000 twists per meter and heat-set. It is stated that a knitted fabric with a special texture with an extremely crisp feel is produced. However, the several types of filaments with irregular cross-sections in the proposed examples have at most four lobes, few recesses, and the depth of the recesses is shallow. , the sharpness is insufficient and the smooth texture is not expressed.

JP-A-57-51808, JP-A-58-8181
No. 63-190083 discloses a technique for using flat threads with constrictions to obtain animal hair-like artificial fibers and artificial fur (Figs. 5 and 6). It is not an elliptical shape, but a normal flat thread, that is, the length of the short axis direction is approximately constant at any position along the long axis direction, and several constrictions are added to it. When this fiber is made into a woven or knitted fabric for general clothing, since it is a flat yarn, it easily bends in the short axis direction in the fiber cross section, and when it is made into a woven or knitted fabric, it does not have firmness or stiffness, easily becomes stiff, and is smooth. It also has almost no texture.

JP-A-61-152849, JP-A-63-1.2
Publication No. 737 discloses a flat yarn with irregularities used for a pile fabric for interior decoration (Figs. 7 and 8), but both have the same fiber cross section as the above-mentioned known examples. When made into a woven or knitted fabric for general clothing, it lacks firmness and waist, tends to sag, and lacks a smooth texture.

On the other hand, basic dyeable polyester is well known as a polymer with excellent dyeability. As basic dyeable polyesters, those obtained by copolymerizing an isophthalic acid component having a metal sulfonate group, for example, a 5-sodium sulfoisophthalic acid component, have been known as disclosed in Japanese Patent Publication No. 34-10497.

However, in order to raise the dyeability to a satisfactory level, this product must be copolymerized with a large amount of an isophthalic acid component (hereinafter abbreviated as S component) having a metal sulfonate group. When a large amount of the S component is copolymerized, the polymer whose degree of polymerization has been increased to a level required for fibers becomes difficult to spin due to the thickening effect of the S component. Therefore, in order to spin a polymer copolymerized with a large amount of the S component by a conventional method, it is necessary to lower the degree of polymerization of the polymer to a range where the melt viscosity can be normally used for spinning. However, as a result, the yarn strength decreases,
There were drawbacks such as deterioration in thread-spinning properties and passability through higher-order processes, and drawbacks in which its uses were limited. Furthermore, the addition of a large amount of S component also causes a decrease in the alkali resistance of the yarn and a decrease in the light fastness of the dyed product, which also limits the uses of the resulting polyester yarn.

On the other hand, especially in the field of thin clothing, it is important to control light transmittance,
For the purpose of preventing so-called see-through, polyester fibers containing a matting agent such as titanium oxide as a light shielding agent are widely used.

In addition, particles such as titanium oxide not only act as a light shielding agent, but also have the effect of eliminating the sliminess characteristic of synthetic fibers and imparting a dry touch feel and milky color to the final woven or knitted product. This is because the matting agent in the fibers diffusely reflects light, and the matting agent on the fiber surface falls off due to the alkali weight loss treatment that is often performed when manufacturing woven and knitted fabrics, creating minute irregularities on the fiber surface. It is believed that.

However, as consumer awareness regarding clothing has increased, consumer demands have become more diverse and sophisticated, and the conventional techniques described above are no longer able to meet these demands. Particularly in high-quality woven and knitted fabrics, there is an increasing demand for so-called specialty products with color development and unique texture.

[Problems to be Solved by the Invention] The purpose of the present invention is to provide an anti-transparent material with good dyeability, high yarn strength, excellent color development (deep color) and sharpness, milky luster, and softness. It is an object of the present invention to provide polyester fibers that have a unique smooth and novel feel and can be suitably applied to high-grade woven and knitted fabrics.

[Means for Solving the Problems] The object of the present invention described above is to reduce the amount of isophthalic acid component containing a metal sulfonate group to 0,
7 to 2.4 mol% polyalkylene glycol component with a molecular weight of 90 to 6000 to polyester
Copolymerized with 0% by weight, and 1.3% or more of matting agent 8.0% by weight
A fiber made of modified polyester containing % by weight or less, which simultaneously satisfies the following (a) to (e) in the cross-sectional shape of the fiber, and has an elliptical shape as a whole and has 8 lobes. The shape can be achieved by uneven cross-section polyester fibers.

(a) The long axis A, which is the longest line in the fiber cross section, and the short axis B, which is perpendicular to the long axis A and is the longest line, have the following relationship.

1.3≦A/B≦2.5 (b) Eight leaves are arranged facing each other, three leaves each, on both ends of the long axis A and on both sides with the long axis A as the axis of symmetry, and are separated from the adjacent leaves. There are depressions between the leaves.

(c) Among the line segments between the vertices of both leaves facing each other with the long axis A as the axis of symmetry, the longest length C, excluding the central portion, has a relationship with the short axis B as shown in the following equation.

0.5≦C/B≦0.8 (d) The shortest length D between both recesses facing each other with the long axis A of the recesses between the leaves in the short axis direction as the axis of symmetry is equal to the length C. It is related to the formula.

0.5≦D/C≦0.9 (e) When the longest line segment among the line segments between each intersection defined below is 1, the other line segments are all 0.6 to 1. It is 0.

Both leaves facing each other with the long axis A as the axis of symmetry Each intersection between the line between the vertices and the major axis, and Length of recess between leaves in short axis direction Both recesses facing each other with sleeve A as the axis of symmetry Each intersection of the line connecting the bottom points and the long axis A.

The polyester fiber of the present invention will be explained below.

The greatest feature of the fiber of the present invention is its specific cross-sectional shape,
It has an elliptical shape as a whole and has eight lobes. The following will be explained based on the drawings.

FIG. 1 is a schematic diagram for explaining the cross-sectional shape of the fiber of the present invention. A hypothetical cross-sectional shape connecting the outermost edges of each leaf (i, approximately elliptical, with almost no straight parts on the outer periphery and a curved line. A line segment in the long axis X direction in the cross section is A, the short axis A line segment in the Y direction is indicated by B. In the present invention, the ratio A/B of the long axis length to the short axis length B is an important factor for the color development level, and a range of 1.3 to 2.5 is required. If A/B is less than 1.8, the effect of improving color development is not observed, and if A/B exceeds 2.5, spinning properties and unwinding properties deteriorate, and when made into woven or knitted fabrics, The firmness of the fist is small, making it easy to get tired. A/B is 1.4 to 2.3.
is preferable, and 1.5 to 2.1 is more preferable.

The eight leaves in the present invention mean three leaves on each side of the long axis in the short axis direction, that is, a, b, c, ab'' a
', and there is one leaf at each end of the long axis, namely d and d-. It also has recesses between all the leaves.

Here, the recesses adjacent to the lobes d and a' are not convex, and may include linear shapes, but are preferably concave. Both leaves opposite the long axis of the leaf that are not in the central part of the leaf in the direction of the short axis, i.e. a and a' or C and a'
When the longest length between the vertices is C, the ratio C/B of C to the short axis length B (the length between the central leaves, b-) is 0.
It needs to be in the range of 5 to 068. This is B
This means that C is larger than C, which is important for giving a smooth and novel texture to woven or knitted fabrics. It is also important for giving a unique soft feel.

This seems to be related to the area of the fibers that come into contact with the fingers when they touch the woven or knitted fabric, as well as the shape and size of the fingerprints and irregularities.

Further, the C/B value is important for increasing elegant gloss, color development, and clarity. When the shortest length between the concave portions facing the long axis of the concave portions between the leaves in the short axis direction is D, the ratio D/C of D to C (the length between the apexes of the leaf) is 0.
It needs to be in the range of 5 to 0.9.

In other words, the value of D/C represents the size of the recess between the leaves in the short axis direction; a large D/C means a small recess, and a small D/C means a large recess. are doing.

The size of the recesses greatly affects color development, sharpness, gloss, glitter, and texture. If the D/C is large, the recesses will be shallow and a straight portion will be provided at the outer periphery of the fiber, which is disadvantageous in terms of color development, sharpness, gloss, glitter, and texture. Therefore, D/C is 0,
Must be 9 or less.

In addition, if D/C is too small, the constriction of the cross section of the fiber will easily bend during processing of the woven or knitted product or when the woven or knitted product is used as clothing, making it impossible to maintain the elliptical shape. Color development, clarity, gloss, glitter
And the feel to the touch has deteriorated, which is not good. For this reason, D/C is required to be 0.5 or more. From the above point, D/C is preferably in the range of 0.6 to 0°8.

Connect the intersection of the long axis and the line connecting the apex of the leaf facing the long axis of the leaf in the short axis direction, and the bottom point of the recess facing the long axis of the recess between the leaves in the short axis direction. The length between all adjacent intersections between the intersections of the double line and the major axis is, when the length of the longest line segment between the intersections is 1, the length of any of the line segments is must be between 0.6 and 1.0.

This range means that the left and right leaves and recesses are approximately symmetrical when the short axis is considered as the axis of symmetry. If the lengths of the line segments between the intersection points are significantly different, color development, sharpness, gloss, etc. will be poor. Therefore, the smaller the variation in the length between the intersections, the better. When the longest length between the intersections is 1, the line segment between each intersection is preferably 0.7
-1.0, more preferably 0.8-1.0, preferably 0.9-1.0. Further, it is preferable that the upper and lower leaves and the recessed portions on both sides with the long axis as the axis of symmetry are symmetrical.

Next, the polyester in the present invention will be explained. The polyester in the present invention has an S component of 0.7 to 2.
It is a polyester copolymerized with 0.2 to IOi weight % of a polyalkylene glycol component having a molecular weight of 90 to 6,000 and containing 1.3 to 8.0 weight % of a matting agent.

By copolymerizing the glycol component in the S component copolymerization system, the following becomes possible.

One of them is that by copolymerizing the polyalkylene glycol component, satisfactory dyeing properties can be imparted even if the amount of copolymerization of the S component is reduced. This is because the polyalkylene glycol component has the function of increasing the effective utilization rate of the S component in the polymer for basic dyes. Secondly, by copolymerizing the polyalkylene glycol component, a polymer with a higher degree of polymerization can be obtained even if the melt viscosity is the same compared to the S component alone copolymerized system. This is because the polyalkylene glycol component has the function of lowering the melt viscosity of the polymer in the S component copolymerization system without lowering the degree of polymerization.

The polyester fiber of the present invention is a fiber having irregularities on the circumferential surface of the cross-section of the copolyester fiber, but only an S component copolymer that does not substantially contain polyalkylene glycol and has the same level of dyeability is used. It has the following effects compared to copolymerized polyester.

It has high yarn strength, good spinability and passability through higher processes,
High alkali resistance. In the dyeing finishing process, alkaline weight loss processing is often performed, and since the alkali resistance is high and the polymer itself has the ability to improve strength, the strength is synergistically increased.

In the present invention, the S component is a compound represented by the following formula, specifically dimethyl (5-sodium sulfo) isophthalate, bis-2-hydroxyethyl (5-sodium sulfo) isophthalate, bis-4-hydroxy Butyl (5-sodium sulfo) isophthalate and the like can be mentioned.

303M (However, M represents an alkali metal such as Na, Li, etc., and ASA- represents -CH3 or -(cH2)nOH. n represents an integer of 2 or more.) A preferable S component is dimethyl (5 -sodium sulfo)isophthalate and bis-2-hydroxyethyl (5-sodium sulfo)isophthalate. The S component must be copolymerized with 0.7 to 2.4 mol% of the polyester.
．． It is preferable that 9 to 2.0 mol% copolymerization is carried out. S
If the content of the component is less than 0.7 mol %, satisfactory dyeability cannot be obtained even if the amount of glycol copolymerized is increased or the dyeing temperature is raised.

This is due to the lack of S component in the polymer that reacts with the basic dye. On the other hand, if the polymer contains more than 2.4 mol % of the S component, it will be difficult to spin it by a normal method due to the thickening effect. The polyalkylene glycol component must have a molecular weight in the range of 90 to 6,000. If the molecular weight is less than 90, the effect of improving dyeability will be small, which is not preferable. In addition, a polyalkylene glycol component having a molecular weight exceeding 6,000 is undesirable because it reduces the light fastness of dyed fibers obtained from a polymer copolymerized with the polyalkylene glycol component. A more preferable molecular weight of the polyalkylene glycol component is 1
00 to 4000, particularly preferably 100 to 120
It is 0. Polyalkylene glycol components having a molecular weight of 90 to 6,000 include neopentyl glycol, 1.4-
Butanediol, 1.5-bentanediol, 1.6-
hexanediol, 1,4-cyclohexanediol,
1,4-cyclohexane dimetatool, bisphenol A-ethylene oxide adduct, etc., and more preferably a polyalkylene glycol represented by the following formula.

A (cn H2n O) t H (A is Cm H2114to or OH, (1 is 1 to 10
, n is 2 to 5, and the bottom is 2 to 65) The copolymerization amount of the polyalkylene glycol component needs to be 0.2 to 10% by weight based on the polyester. If the amount is less than this range, the effect of improving dyeing properties will be small, and if it is more than this range, the physical properties, especially heat resistance, will be greatly deteriorated. Therefore 0.
A range of 3 to 7% by weight is more preferred.

The degree of polymerization of the polyester in the present invention is preferably 80 to 100, more preferably 90 to 100. If the degree of polymerization is too low, the yarn strength will not be at a satisfactory level, and if the degree of polymerization is too high, the melt viscosity of the polymer will increase, making spinning difficult, which is not preferred.

The fiber of the present invention is produced by adding a matting agent to the above-mentioned polyester in 1.
It is necessary that the content be 3% by weight or more and 8.0% by weight or less. When the content of the matting agent is less than 1.3% by weight, the anti-transparent properties, milky color, and dry touch feel are all unsatisfactory.

If the matting agent content exceeds 8.0% by weight, the yarn strength will be low (this is not good as it will cause fluffing or yarn breakage during weaving or knitting). If it exceeds %, the door material becomes clogged quickly during the spinning process, especially during polymer filtration during spinning, making stable spinning for a long period of time difficult, which is also bad from this point of view. is preferably 2.0 to 7.0% by weight.

The matting agents contained in the fibers of the present invention include titanium oxide, zirconium oxide, magnesium oxide, aluminum oxide, silicon oxide, antimony oxide, zinc oxide, lead tungstate, calcium tungstate, calcium carbonate, barium sulfate, etc. Any material may be used as long as it exhibits the effects of the invention and can be stably dispersed in polyester, but from the viewpoint of dispersibility, titanium oxide, silicon oxide, zinc oxide, and calcium carbonate are preferred (7), and titanium oxide is more preferred. Preferably, the average particle size of the matting agent is 1 from the viewpoint of dispersibility.
The thickness is preferably 0.7 microns or less, more preferably 0.7 microns or less.

Further, from the viewpoint of silk-spinning property, the maximum particle size is preferably 5 microns or less, more preferably 3 microns or less.

The dyeing temperature of the fibers of the present invention can be changed as appropriate depending on the polymer composition, but is preferably in the range of 1.10 to 140°C. In addition, the polyester referred to in the present invention means that at least 80 mol% of the structural units are ethylene terephthalate or butylene terephthalate, and 10 mol% or less, preferably 5
Other components may be copolymerized in an amount of mol % or less.

The fibers of the present invention can improve yarn strength, spinnability, high-order passability, dyeability, alkali resistance, light resistance, etc. by using modified polyester, and also have the effect of maintaining the shape of the fibers. In addition, since it contains an appropriate amount of matting agent, it has anti-transparent properties, can develop a milky luster, and can also provide a dry touch feeling. Furthermore, by combining it with a unique cross-sectional shape, it is possible to improve color development and clarity, and also to impart a new, soft and unique smooth texture.

The fibers of the present invention may contain well-known additives such as antioxidants, optical brighteners, flame retardants, ultraviolet absorbers, and the like, to the extent that they do not impede the effects of the present invention.

The fibers of the present invention may be filament-like or cotton-like, and preferably have a fineness in the range of 0, 5 to 10 denier, which is usually used for clothing, and may be a fineness mix or a heat shrink mix. Alternatively, it can be used in combination with other fibers.

As explained above, the elliptical uneven cross-section polyester fiber of the present invention has anti-transparent properties, good dyeability, high yarn strength, excellent color development and clarity, and has a milky luster.
It is suitable for high-grade woven and knitted fabrics, especially high-grade fabrics, which have a soft, unique smooth and novel feel.

In addition, the same effect can be achieved by performing a known bulking process such as false twisting or fluid processing.

The elliptical uneven cross-section polyester fiber of the present invention can be suitably produced by the following method.

FIG. 2 is a plan view showing an example of the shape of a polymer discharge hole of a spinneret for melt-spinning the fiber of the present invention. It can be obtained by melt-spinning the polyester of the present invention by a conventional method using a spinneret having the above-mentioned discharge holes, winding it up while cooling and adding oil, and then stretching it at a desired draw ratio.

[Example J] The present invention will be specifically described below with reference to Examples. Each measurement value in the examples was determined according to the following method.

A. Polyalkylene glycol component content The polymer was subjected to amine decomposition and then subjected to gas chromatography.

B. Determine the number of terminal groups per unit weight of polymerization degree by a commonly used method,
Calculated using the following formula.

Degree of polymerization = C1 Light fastness It was measured on a blue scale basis when photofading according to JIS-L 1044 using a fade meter.

D. Dyed malachite green (trade name manufactured by Kanto Kagaku) 5% o w
f, acetic acid 0.5 g/ff, acetic acid sorter 0.2 g/Q, bath ratio 1:too, temperature 120°C, solvent water.

Using an E8 chromogenic SN color computer [manufactured by Suga Test Instruments Co., Ltd.], five or more pieces of fabric with a constant black dye exhaustion rate were stacked together, and the L value was measured in a state where no irradiation light was transmitted. (The smaller the L value is, the greater the color development is.) F, Vividness, Glossiness, and Texture A fabric dyed under certain dyeing conditions was sensory evaluated.

G, cross-sectional shape of polyester fiber It was measured and calculated from a cross-sectional photograph of the fiber.

H9 anti-transparent is rated using an 8M color computer [manufactured by Suga Test Instruments Co., Ltd.] by placing a white body and a black body behind the fabric and measuring the difference in the L value of each. It was used as a measure of gender.

Example 1 98.3 mol% of terephthalic acid and dimethyl (5-
2.3% of titanium oxide with an average particle size of 0.5 microns and a maximum particle size of 2 microns is added to a polyester copolymerized with 1.7 mol% of sodium sulfo)isophthalic acid and polyalkylene glycol in the type and amount shown in Table 1. A polymer containing % by weight (degree of polymerization of 90 to 100) was melt-spun at a spinning temperature of 300° C. using a spinneret having a discharge hole shape as shown in FIG. 2, and wound at a speed of 1600 m 2 /min. Subsequently, hot roll drawing was carried out at a drawing speed of 600 m/min, a heating roller temperature of 90° C., and a drawing ratio such that the drawn yarn elongation was 30±2%, to obtain a drawn yarn of 75 denier and 24 filaments. The cross-sectional shape of the fibers of the drawn yarn had an elliptical uneven cross-section as shown in FIG. These drawn yarns were twisted at 200 T/m and glued as warp yarns, and left as they were as weft yarns at a weaving density of 110 yarns/inch in warp and 90 yarns/inch in weft to weave a habutae.

Table 1 shows various evaluation results such as the details of the cross-sectional shape of the fibers and the characteristics of the fibers.

The cross-sectional shape of the fiber is roughly as shown in Figure 1, for example,
Experiment No. 1 (invention) fiber A is 2547 microns, B is 15.5 microns, C is 1.0.2 microns, D
is 7.5 microns, and A/B is I.

66, C/B is 0.66, D/C is 0.74, other experimental levels are A/B 1.65-1.75, C/B 0
．． 65 to 0.72, and D/C was in the range of 0.66 to 0.75.

The fabrics using Experiment Nos. 1 to 7 (this invention) have high yarn strength, good dyeability, color development, and light fastness, clarity, milky luster, and a new soft and smooth texture. Met. In addition, the anti-transparent property was also good.

Experiment No. 8 (Comparative Example) The woven fabric used had low yarn tenacity and insufficient color development. The fabric used in Experiment No. 099 (Comparative Example) had low dyeability and insufficient color development, and the fabric used in Experiment No. 1O (Comparative Example) had poor light fastness. In addition, thread breakage based on warp threads during weaving in Experiment No. 8 (comparative example) was as high as 36 times/107m, whereas in all other standards, it was less than 0.4 times/107m, which was good. .

(Left below) Example 2 98.3 mol% of terephthalic acid and dimethyl (5-
A polymer containing 1.7 mol% of sodium sulfo)isophthalic acid and 2.0% by weight of polyethylene glycol having a molecular weight of 1000 as polyalkylene glycol (degree of polymerization 91) contains 2.3% by weight of titanium oxide. The same spinning process as in Example 1 was carried out, except that a spinneret with the discharge hole shape shown in Fig. 2 and various dimensions was used.
It was evaluated by stretching and weaving. The results are shown in Table 2. The cross-sectional shapes of the fibers of the drawn yarn were elliptical cross-sections with various shapes as shown in FIG. 1, and the cross-sectional shapes were detailed as shown in Table 2.

Experiment No., LL (Comparative Example) The fabrics used had poor color development due to the small A/B ratio, insufficient smooth and loose texture, strong firmness and stiffness, and lacked a soft feel. Also,
The clarity and milky gloss were also insufficient.

Experiment No. 12-15, Experiment No. 1g, No. 21
, No. 22 (all of the present invention) have a cross-sectional shape of A/B of 1.40 to 2.41 and C/B of 0.59 to
0.7■, D/C is in the range of 0.59 to 0.81,
There were concave portions between adjacent leaves, and the fabric had good color development, a soft and smooth texture, and good milky luster and sharpness.

In Experiment No. 1B (comparative example), single yarn breakage occurred during spinning, single yarn fell off on the winding drum, and yarn breakage occurred during drawing due to poor unwinding properties of the drum. In addition, the fabric using this thread lacked firmness and elasticity, lacked sharpness, and lacked a sense of luxury.

Experiment No. 17, No. 19, No. 20, No.
, 23 (both comparative examples) The woven fabrics used had C/B and D/C too small or too large in the cross-sectional shape of the fibers, and both had poor coloring properties, and each of the fabrics was not shown in the table. It had some flaws, and it didn't feel luxurious.

In addition, in all levels, the transparency property and the dry touch feeling were good.

(Space below) Example 3 A polymer containing titanium oxide in the content shown in Table 3 (composition is the same as in Example 1) was added to the polyester of Example 2 and subjected to spinning, stretching, and weaving in the same manner as in Example 1. I did it and evaluated it. The results are shown in Table 3.

In Experiment No. 24 (comparative example), the titanium oxide content was low, so the transparency, milky gloss, and dry touch feeling were poor. In addition, the smooth texture was also slightly poor.

Experiment No. 30 (comparative example) had good anti-transparency, milky gloss, and dry touch feeling, but the color development and clarity were low, and the tear strength of the fabric was low due to low thread strength. Furthermore, due to the large amount of fuzz generated during weaving, the quality was extremely poor and had no commercial value. Also,
During spinning: Due to clogging of the filter layer; door pressure increased significantly, yarn breakage occurred frequently, and bistable spinning was impossible for more than 10 hours.

Experiments No. 25 to No. 29, which are examples of the present invention, were satisfactory in terms of color development, sharpness, transparency, milky gloss, and dry touch feeling.

However, in Experiment No. 29, a slight decrease in tear strength was observed, which was considered to be due to a decrease in yarn strength.

In addition, at all levels of the experiment, the cross-sectional shape of the fibers of the drawn yarn was A/B of 1.67 to ■, 75, and C/B of 0.6 to 0.
．． 7, D/C was in the range of 0.65-0.75.

In addition, in all levels except experiment No. 24, the woven fabric had a soft and smooth texture.

(The following is a blank space) Example 4 Using the polymer of Example 2 and using a spinneret with a discharge hole shape of Q type, Y type, f type, +H-1- type, and H type, Example 1 was prepared. Spinning, drawing, and weaving were carried out in the same manner as above, and evaluation was made. Table 4 shows the cross-sectional shape of the obtained fibers and the evaluation results of the woven fabric.

Experiment No., 31-No., 35 (Comparative example) The ino textiles used had poor color development and brightness, and each had the drawbacks shown in the table, making it unsuitable for application to high-grade textiles. It was something. In addition, the anti-transparent property was good at all levels without much difference.

(The following is a blank space) [Effects of the Invention] The elliptical uneven cross-section polyester fiber of the present invention has the following effects.

(1) 0.7 to 2.4 mol% of the constituent polyester or isophthalic acid component containing metal sulfonate groups,
Since it is a modified polyester copolymerized with 0.2 to 10% by weight of a polyalkylene glycol component having a molecular weight of 90 to 6,000, it has high yarn strength and is excellent in dyeability and light fastness of dyed products.

(2) The cross-sectional shape of the fiber is elliptical as a whole, and the outer periphery has unevenness, so it has a softer touch compared to round or triangular cross-section yarns, and the reflected light reflects at a wide angle. Because it is diffusely reflected, it has an elegant luster, excellent color development and clarity, and creates a high-class image.

(3) Gives the woven or knitted fabric appropriate firmness and elasticity, and has good drapability.

(4) The synergistic effect of the modified polyester with a specific matting agent content and the specific cross-sectional shape improves the color development and clarity of woven and knitted fabrics, develops an elegant milky luster, and provides a unique dry touch feeling. Gives a smooth new texture.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of a typical fiber in the present invention. FIG. 2 is a plan view showing an example of the shape of a polymer discharge hole of a spinneret for producing fibers in the present invention. FIGS. 3 to 8 are cross-sectional views showing an example of a conventional fiber having unevenness.

Claims (1)

[Claims] (1) 0.7 to 2.4 mol% of the isophthalic acid component containing a metal sulfonate group based on the total dicarboxylic acid component,
A polyalkylene glycol component having a molecular weight of 90 to 6,000 is copolymerized with 0.2 to 10% by weight of polyester, and a matting agent is 1.3% by weight.
A fiber made of modified polyester containing 8.0% by weight or less, which has the following (a) to (
A polyester fiber having an elliptical uneven cross section, which satisfies e) and is characterized by having an elliptical shape as a whole and having eight lobes. (a) Long axis A, which is the longest line in the fiber cross section, and long axis A
The short axis B, which is perpendicular to and is the longest line part, has the following relationship. 1.3≦A/B≦2.5 (b) Eight leaves are arranged facing each other, three leaves each, on both ends of the long axis A and on both sides with the long axis A as the axis of symmetry, and with adjacent leaves. There are depressions between the leaves. (c) Of the line segments between the vertices of both leaves facing each other with the long axis A as the axis of symmetry, the longest length C, excluding the central portion, has a relationship with the short axis B as shown in the following equation. 0.5≦C/B≦0.8 (d) The shortest length D between both concave portions facing each other with the long axis A of the concave portions between the leaves in the short axis direction as the axis of symmetry is equal to the length C. It is related to the formula. 0.5≦D/C≦0.9 (e) Among the line segments between each intersection defined below, when the longest line segment is 1, all other line segments are 0.6 to 1. 0
It is. Each intersection of the long axis and the line between the vertices of both leaves that face each other with the long axis A as the symmetry axis, and the bottoms of the two recesses that face each other with the long axis A of the recess between the leaves in the short axis direction as the symmetry axis. Each intersection of the line connecting the points and the long axis A.