JP2000220029A - Polyester modified cross-section yarn and combined filament yarn - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain both a modified cross-section yarn having good water absorbing performances and excellent in a soft feeling in spite of body, a stiffness feeling and a dry feeling possessed thereby by forming the shape of a synthetic fiber into a modified cross-sectional shape and a combined filament yarn using the yarn. SOLUTION: This polyester modified cross-section yarn has >=3 radially extending main trunks 1 and >=3 protruding parts 2 at the tip of each main trunk 1 and satisfies the following formulae I and II in the cross-sectional shape of a single filament: formula I: r<=3 and formula II: 3<=R/r<=8 [r is the maximum tip radius (unit: μm) in the protruding parts 2; R is the minimum radius (μm) of a circle circumscribed with the >=3 protruding parts 2]. The initial Young's modulus of the yarn is <=40 g/d.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a polyester modified cross-section yarn which is particularly suitable as a material for clothing such as innerwear, sports clothing and blouses, which becomes a fabric having excellent water absorption performance and soft texture when knitted and woven. The present invention relates to a mixed fiber using the same.

[0002]

2. Description of the Related Art Synthetic fibers such as polyester fibers are widely used because they have many excellent properties. However, since these fibers are hydrophobic, natural fibers such as cotton and hemp and chemical fibers such as rayon are used. It is inferior in water absorbency and moisture absorbency as compared with fiber, and its use in fields requiring wearing comfort is limited.

Therefore, in order to impart water absorbency to synthetic fibers such as polyester fibers, a method of forming a hydrophilic film on the fiber surface has been mainly adopted, and besides, a discharge treatment is performed on the fibers. Methods, a method of graft-polymerizing a hydrophilic compound such as acrylic acid and methacrylic acid, and a method of etching the surface of a synthetic fiber with a chemical have been proposed. However, these fibers which have been given water absorbency by post-processing have the disadvantages that their performance is not sufficient, and that the processing steps are complicated and the cost is high.

Further, a method has been put to practical use in which the shape of synthetic fibers is deformed or the surface thereof is made porous so as to improve the water absorption by utilizing the capillary phenomenon. Among them,
The nine-leaf cross-section yarn disclosed in Japanese Patent Publication No. Sho 62-40442 exhibits excellent water absorption. However, this fiber is made of polyethylene terephthalate (hereinafter abbreviated as PET). Due to the rigidity of PET, this modified cross-section yarn has high firmness and firmness, but lacks softness. It has a drawback that it is not suitable for applications requiring softness such as inners.

Further, there has been proposed a fiber in which a moisture absorbing component such as polyetheramide or polyethylene glycol is contained in polyester. However, polyester fibers are generally subjected to an alkali weight reduction treatment to improve the texture. In this alkali weight reduction step, the moisture-absorbing component swells, causing a sheath cracking phenomenon or elution of the moisture-absorbing component into the alkali. And has not yet been put to practical use.

Therefore, Japanese Patent Application Laid-Open No. 9-217230 proposes a composite fiber in which a moisture absorbing component is used as a core component and a sheath component is made of polyamide. According to this fiber, the sheath cracking phenomenon and elution of the moisture-absorbing component were eliminated, but the polyamide fiber had a slimy feeling, and thus did not reach the polyester fiber in terms of texture.

[0007]

SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems and has good water absorption performance by deforming the shape of the synthetic fiber, and has a firmness, firmness and dryness. An object of the present invention is to provide a modified cross-section yarn excellent in softness and a blended yarn using the fiber.

[0008]

Means for Solving the Problems The present inventors have made intensive studies to solve the above-mentioned problems, and as a result, have reached the present invention.
That is, the present invention provides the following (1) and (2). (1) In the cross-sectional shape of a single fiber, it has three or more radially extending main trunks and three or more projecting portions at the tip of the main trunk and satisfies the following formulas (1) and (2). A polyester modified cross-section yarn, wherein the yarn has an initial Young's modulus of 40 g / d or less. r ≦ 3 (1) 3 ≦ R / r ≦ 8 (2) r: the largest one among the tip radii (unit: μm) of the protrusions R: the radius (μm) of a circle circumscribing three or more protrusions (2) Consisting of a hygroscopic conjugate fiber having a core containing a thermoplastic water-absorbing resin composed of a crosslinked product of polyethylene oxide and a polyamide as a sheath component, and the modified cross-section yarn described in (1). Mixed fiber yarn characterized by the following.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail. First, the modified cross-section yarn of the present invention will be described with reference to the drawings. FIG. 1 is an explanatory cross-sectional view showing an embodiment of a cross-sectional shape of a single yarn constituting the modified cross-section yarn of the present invention, and FIG. 2 is a schematic diagram showing a cross-sectional shape of the modified cross-section yarn composed of the single yarn of FIG. It is. The modified cross-section yarn of the present invention has three or more radially extending main trunks 1 and three or more projections 2 at the tip of the main trunk 1 in the cross-sectional shape of a single fiber. When the woven or knitted fabric is formed by the projections 2, the woven or knitted fabric has the appearance of a woven or knitted fabric using extra-fine yarns, and has a very soft and dry feel.

In the formula (1), r is the largest of the tip radii of the projections. In order to obtain a rich drape property and a soft and dry feel when woven or knitted, r should be 3 μm or less. is necessary. When r exceeds 3 μm, a dry feeling is obtained but a rough feeling is obtained, and the soft feeling indispensable for inner use or the like is not exhibited. Note that each of the protrusions may be different as long as the tip radius r is within 3 μm.

In the formula (2), R is the smallest of the radii (μm) of the circles circumscribing the three or more projections, and is the ratio R / r to the radius r of the projections described above. Exceeds 8, the length of the protruding portion becomes extremely long, and not only the water absorption rate is saturated, but also the drape performance of the fabric is lowered, and the fabric is liable to be caught, and the quality is deteriorated. On the other hand, when the value of R / r is less than 3, the projections and depressions of the projections decrease, and the water absorption performance decreases. In addition, the woven or knitted fabric lacks a dry feeling with a slimy feeling, and the independence of each projection is lost, so that it does not have a soft feel and does not appear as if ultrafine yarns are gathered.

The number of main trunks extending radially and the number of projections provided at the tip of each main trunk can be selected according to the desired luster and feel, but if the number of main trunks is less than three, the main trunks are connected. Since the bay opening is flat and long, the gloss becomes strong, causing not only glare and slimy feeling but also poor water absorption performance. The same is true for the number of projections provided at the respective leading ends of the main trunks. When the number of projections is less than three, a slimy feeling occurs, the dryness is lacking, and the water absorption is poor.

However, it is not preferable to increase the number of main trunks and protrusions without limit. If the number is increased more than necessary, the shape of orifices having various shapes when spinning the yarn becomes complicated. The production cost increases,
Further, the number of orifices is preferably five or less because the area of the orifice becomes large and troubles such as breakage during spinning are likely to occur. In addition, the number of the protrusions at the main trunk and the distal end of the main trunk may be the same or different in one yarn within this range.

R and R are a cross-sectional photograph of a single fiber taken by using a microscope, appropriately enlarged, and the tip radius r of the projection.
And a radius R circumscribing at least three protrusions is obtained by measurement, and the average value is obtained. The definition of the tip radius r is the same as that described in Japanese Patent Publication No. 36-20770.

Further, in order to impart a suitable soft feeling to the inner or the like, the initial Young's modulus of the modified cross-section yarn must be 40 g / d or less. If the initial Young's modulus is more than 40 g / d, the fabric lacks a soft feeling even when used as fine yarn. As a method for reducing the initial Young's modulus to 40 g / d or less, a method in which a part or all of the yarn is composed of a polymer having a relatively flexible structure is preferable.

Above all, it is preferable to use a polyester made of polytrimethylene terephthalate (hereinafter abbreviated as PTT), which is excellent in dimensional stability and light resistance, and can further improve the feeling by alkali weight reduction processing.

[0017] These polyester components may contain a small amount of a copolymer component.
5-sodium sulfoisophthalic acid, isophthalic acid, phthalic anhydride, aromatic dicarboxylic acid components such as naphthalenedicarboxylic acid, adipic acid, aliphatic dicarboxylic acid components such as sebacic acid, ethylene glycol, diethylene glycol, 1,4-butanediol, Glycol components such as 1,4-cyclohexanedimethanol, alkylene oxide adducts of bisphenol A and alkylene oxide adducts of bisphenol S, and hydroxycarboxylic acid components such as 4-hydroxybenzoic acid and ε-caprolactone.

Additives, matting agents, pigments and the like for the purpose of imparting functions such as antistatic, flame retardant, light fastness, and antifouling properties to the above-mentioned polymers as long as the effects are not impaired. May be blended.

Next, the mixed fiber of the present invention is obtained by mixing the above-mentioned modified cross-section yarn and a core-sheath type hygroscopic conjugate fiber containing a thermoplastic water-absorbent resin in the core. The thermoplastic water-absorbing resin contained in the core of the hygroscopic conjugate fiber is made of a crosslinked product of polyethylene oxide. In particular,
It is obtained by reacting polyethylene oxide with a polyol and an aliphatic diisocyanate compound. The polyol is glycols such as ethylene glycol, diethylene glycol and propylene glycol, and the aliphatic diisocyanate is dicyclohexylmethane-4,4'-diisocyanate. And 1,6-hexamethylene diisocyanate.

Above all, those which are insoluble in water, capable of being melt-processed at a temperature of 300 ° C. or less, and having a water absorption capacity of 20 times or more of their own weight are preferable. As such a thermoplastic water-absorbing resin, “Aqua Coke” manufactured by Sumitomo Seika Co., Ltd. is exemplified.

As the core component, this resin may be used alone or may be contained in another polymer. When it is contained in another polymer, it is preferred that it be contained in an amount of 5% by weight or more of the entire conjugate fiber in order to exhibit water absorption performance. As another polymer, it is preferable to use a polyamide in consideration of compatibility with the polyamide of the sheath.

Polyamide is used for the sheath component of the hygroscopic conjugate fiber. When an aromatic polyester such as polyethylene terephthalate is used as a sheath component, cracks in the sheath portion and elution of the thermoplastic water-absorbing resin from the core portion occur in the alkali weight reduction treatment, and the water absorbing performance decreases. Further, polyolefins such as polyethylene and polypropylene are not suitable for clothing use.

Examples of the sheath polyamide include homopolymers such as nylon 6, nylon 66, nylon 46, nylon 11, nylon 12, nylon MXD6 (polymethaxylylene adipamide), and copolymers or mixtures containing these as main components. Is preferably used.

The composite form may be a single-core type or a multi-core type.
The concentric core-sheath composite form is preferred from the viewpoint of dyeing fastness and yarn-making properties.

The core / sheath ratio is not particularly limited, but the core: sheath ratio is 20:80 to 80:80 by weight so as to exhibit water absorption performance and to improve the yarn forming property.
It is preferably 20. At this time, the amount of the thermoplastic water-absorbing resin contained in the core is set to be 5% by weight or more of the entire conjugate fiber.

The mixing ratio of the hygroscopic conjugate fiber and the modified cross-section yarn in the mixed yarn of the present invention is not particularly limited, but is preferably 1: 3 to 3: 1.

Further, it is more preferable that the heat-shrinkage ratio of the modified cross-section yarn and that of the hygroscopic conjugate fiber are different from each other, and that the mixed shrinkage mixed fiber yarn is used in terms of hand. At this time, it is preferable that the heat shrinkage is smaller than the shrinkage of the hygroscopic conjugate fiber and the difference between the two is 1% or more so that the modified cross-section yarn becomes the outer layer of the mixed fiber.

Next, the method for producing the modified cross-section yarn of the present invention will be described. When obtaining the cross-sectional shape shown in FIG.
Using an orifice-shaped spinneret shown in FIG. 3A, spinning is performed at a spinning temperature of 250 to 300 ° C. and a spinning speed of 1200 to 4500 m / min by a normal melt spinning apparatus, and then a drawing temperature of 50 to 50 ° C. is performed by a normal drawing machine. It can be obtained by stretching at a temperature of 120 to 90 ° C and a heat treatment temperature of 120 to 180 ° C at a ratio of 1.4 to 3.5.

The hygroscopic conjugate fiber used in the mixed fiber of the present invention is obtained by subjecting a resin containing a thermoplastic water-absorbent resin as a core component and a polyamide as a sheath component to a composite spinning using a composite spinning apparatus by an ordinary method. Stretching and heat treatment can be performed in the same manner as described above. The mixed fiber of the present invention is obtained by combining and shaping the modified cross-section yarn and the hygroscopic conjugate fiber, but after obtaining each fiber once, it may be combined by a conventional method, Heat treatment or the like may be performed after forming the mixed yarn.

[0030]

Next, the present invention will be described specifically with reference to examples. The measurement and evaluation of the characteristic values in the examples were performed as follows. (A) Initial Young's Modulus The obtained fiber was calculated according to JIS 1013 7.10. (B) Boiling water shrinkage ratio The obtained fiber was subjected to JIS-L-1013 (199).
It was measured by the following method according to 2). A scalpel of 8 turns is taken with an initial load of 1/10 (g / d) using a measuring machine, and a 1/30 (g / d) load is applied to the scab to measure its length L0 (mm). Then, the load was removed and 1/1000
With the load of (g / d) applied, the moss was taken out of the boiling water, and after cooling, a load of 1/30 (g / d) was again applied.
The length L1 (mm) at that time was measured, and the boiling water shrinkage SHW was calculated by the following equation. SHW = [(L0−L1) / L0] × 100 (c) Water Absorption Using a woven fabric made of the obtained fibers, a sample before water absorption was conditioned for 2 hours at a temperature of 25 ° C. and a relative humidity of 60%. After weighing the weight W, the weight W180 of the water-absorbing sample after 180 seconds was measured by the water-absorbing measurement method specified in JIS L 1907 5.3, and the water absorption S was obtained by the following equation. S (%) = [(W180−W) / W 2] × 100 A water absorption of 140% or more was regarded as acceptable. (D) Hygroscopicity Using the obtained woven fabric made of fibers, the fabric was dried at 105 ° C. for 2 hours to measure the weight W0, and then conditioned at 25 ° C. and 60% relative humidity for 2 hours. Measure the weight W1,
The initial moisture content M1 is calculated by the following equation. Subsequently, the sample was allowed to absorb moisture for 2 hours at a temperature of 34 ° C. and a relative humidity of 90%, then the weight W2 was measured, and the moisture absorption M was calculated by the following equation. M1 (%) = [(W1-W0) / W0] × 100 M (%) = [(W2-W1) / W1] × 100 The hygroscopicity of M1 is 2.5% or more and M is 6% or more. Passed. (E) Texture For the texture of the woven fabric made of the obtained fibers, ten panelists scored the overall evaluation of dryness, firmness, stiffness and softness on a scale of 1 to 10, and averaged. The values were evaluated as follows. ：: 9 points or more ：: 8 points or more and less than 9 points Δ: 6 points or more and less than 8 points ×: less than 6 points Of these, ◎ or ○ was accepted. (F) Comfort The clothing using the mixed fiber of the present invention was worn by 10 panelists, and after 30 minutes of light exercise, the comfort in wearing after 1 hour was evaluated on a scale of 10 out of 10. Have you
The average value was evaluated as follows. ：: 9 points or more ：: 8 points or more and less than 9 points Δ: 6 points or more and less than 8 points ×: less than 6 points Of these, ◎ or ○ was accepted.

Examples 1 to 6 and Comparative Examples 1 to 5 Using PTT having an intrinsic viscosity [η] of 0.92, FIGS.
Using a spinneret having 12 orifices of various types shown in F, the spinning was performed at 270 ° C. and a discharge rate of 17.5 g / min, and the film was wound at a winding speed of 3200 m / min. The variously shaped undrawn yarns obtained in this manner were drawn at a drawing temperature of 70 ° C.
It is stretched 1.6 times under the condition of a heat setting temperature of 160 ° C.
50d / 12 with a cutting elongation of 27% and a strength of 3.85 g / d
Thus, a drawn yarn of f was obtained. Table 1 shows the results of measuring the cross-sectional shape and the initial Young's modulus of the obtained modified cross-section yarn. Next, the drawn yarn was used as a warp and a weft, woven into a taffeta structure, and the obtained woven fabric was subjected to post-processes such as scouring, presetting, alkali treatment, and dyeing, to obtain a plain dyed woven fabric of the same color. Table 1 shows the results of evaluation of the water absorption performance and hand of this woven fabric.

Comparative Example 6 The procedure of Example 1 was repeated, except that PET was used instead of PTT. As a result of measuring the cross-sectional shape and the initial Young's modulus of the obtained modified cross-section yarn, the evaluation results of the water absorption performance and the texture of the woven fabric comprising the modified cross-section yarn are shown in Table 1.

[0033]

[Table 1]

As is clear from Table 1, all of the modified cross-section yarns of Examples 1 to 6 satisfy the expressions (1) and (2) defined in the present invention, and the initial Young's modulus is 40 g / d or less. Therefore, the woven fabric obtained from this fiber exhibited a good feeling having both a dry feeling and a soft feeling, and had excellent water absorption performance. In addition, the operability for obtaining the fibers was at a level at which industrial production was possible, and there was no problem. On the other hand, in Comparative Example 1, the number of main trunks was large, and in Comparative Examples 2 and 3, the number of protrusions was small. The woven fabric made of these fibers was poor in water absorption and lacked a dry feel. It became. Further, since the fiber of Comparative Example 4 had an R / r of 8 μm or more, the woven fabric had a low drape property, a reduced texture and quality. In the fiber of Comparative Example 5, since r is 3 μm or more,
Although a dry feeling was obtained, the fabric had a texture lacking a soft feeling. The fiber of Comparative Example 6 was a woven fabric lacking a soft feeling because the initial Young's modulus was too high.

Examples 7 to 10 and Comparative Examples 7 to 9 Nylon 6 having a relative viscosity of 2.6 and aqua coke (modified by water-insoluble polyethylene oxide manufactured by Sumitomo Seika Co., Ltd.) were dry blended at a weight ratio of 85:15. Using a nylon 6 having a relative viscosity of 2.6 for the sheath, and a sheath-to-sheath weight ratio of 5
A concentric core-sheath composite fiber of 0:50 was spun. At this time, the spinning temperature was set to 250 ° C., and the melt spun yarn was cooled by blowing air at 15 ° C. using a 12-hole spinneret, an oil agent was applied, and the yarn was taken out at a speed of 800 m / min. . Next, it is stretched 3.0 times at a heat treatment temperature of 140 ° C.
/ 12f was obtained. The boiling water shrinkage of the obtained composite fiber was 13%. Next, as shown in Table 2, Examples 1, 3, 5, and 6 and Comparative Examples 1, 3, and 6
Using the modified cross-section yarn and the obtained hygroscopic conjugate fiber, a mixed fiber having a core-sheath two-layer structure was obtained according to a conventional method. When the obtained mixed fiber yarn was subjected to relaxation heat treatment in boiling water, it was observed that the hygroscopic conjugate fiber was distributed in the inner layer of the two types of multifilament yarn constituting the mixed fiber and the irregular cross-section yarn was distributed in the outer layer. Was done.
This mixed yarn is used as a warp and a weft, woven in a plain weave at a warp density of 30 yarns / cm and a weft yarn density of 28 yarns / cm, and woven in accordance with a conventional method, and subjected to relaxation, presetting, and alkali reduction to obtain a woven fabric. Was. Table 2 shows the evaluation results of the moisture absorption, the water absorption performance, the texture, and the comfort of the woven fabric.

[0036]

[Table 2]

The woven fabrics obtained from the mixed yarns of Examples 7 to 10 all had good evaluation of water absorption, moisture absorption, and hand. On the other hand, since the fibers of Comparative Examples 7 and 8 used the modified cross-section yarns of Comparative Examples 1 and 3 having low water absorption performance, the obtained woven fabric had low water absorption and was poor in texture. In Comparative Example 9, since the modified cross-section yarn of Comparative Example 6 having a high initial Young's modulus was used, the obtained woven fabric had poor texture.

[0038]

EFFECTS OF THE INVENTION The modified cross-section yarn of the present invention has a low initial Young's modulus, and is excellent in softness, and at the same time, exhibits a special cross-sectional shape.
A woven / knitted fabric suitable for clothing such as innerwear, sports clothing, blouse and the like, having the opposite properties of firmness and softness can be obtained. Further, the mixed fiber of the present invention mixed with a hygroscopic fiber has more excellent water absorption and hygroscopicity, and it is possible to obtain a woven or knitted fabric having a good texture.

[Brief description of the drawings]

FIG. 1 is an explanatory cross-sectional view showing an embodiment of a single yarn of a polyester modified cross-section yarn of the present invention.

FIG. 2 is a schematic view showing one embodiment of a modified cross-section yarn of the present invention.

FIGS. 3A to 3F are schematic views showing the shapes of orifices for obtaining the modified cross-section yarn of the present invention.

[Explanation of symbols]

 1 main trunk 2 protrusion

Claims (3)

[Claims] 1. A cross section of a single fiber having three or more radially extending main trunks and three or more projections at the tip of the main trunk, and satisfying the following expressions (1) and (2). A polyester modified cross-section yarn, wherein the yarn has an initial Young's modulus of 40 g / d or less. r ≦ 3 (1) 3 ≦ R / r ≦ 8 (2) r: the largest one among the tip radii (unit: μm) of the protrusions R: the radius (μm) of a circle circumscribing three or more protrusions The smallest of 2. The polyester modified cross-section yarn according to claim 1, wherein the polyester constituting the single fiber is polytrimethylene terephthalate. 3. A hygroscopic conjugate fiber comprising a resin containing a thermoplastic water-absorbing resin comprising a crosslinked product of polyethylene oxide as a core component and a polyamide as a sheath component, and the modified cross-section yarn according to claim 1 or 2. Mixed fiber yarn characterized.