JP2882692B2 - Composite fiber aggregate and method for treating fabric using the fiber - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polyester composite fiber comprising an alkali-soluble component and an alkali-refractory component. It is related to an aggregate of composite fibers having a high irregularity and a natural spot similar to natural fibers and a soft soft texture by alkali-decomposing the composite fibers by being alkali-decomposed, even though they are the same. is there.

[0002]

2. Description of the Related Art Conventionally, synthetic fibers such as polyester,
Fiber structures such as woven fabrics, knitted fabrics and non-woven fabrics made of polyamide filaments have a higher texture and luster than natural fibers such as cotton and hemp because the single filament denier and cross-sectional shape of the constituent filaments are monotonous. It was monotonous and cold, and the quality as a fiber structure was low.

[0003] In recent years, various attempts have been made to improve the drawbacks, such as deforming the fiber cross section, crimping, and composite fibers. However, at present, the objectives have not yet been sufficiently achieved. is there. For example, JP-A-56-165015,
JP-A-57-5921, JP-A-58-98425,
A composite fiber of an easily soluble polymer and polyester is formed as described in JP-A-61-239010 and the like, and then a post-processing is performed to give a dry touch feeling and a unique gloss. It is applied to woven or knitted fabric, or JP-B-51-7207, JP-A-58-70711.
JP-B-53-35633 and JP-B-56-16231, in which the texture is improved by imparting unevenness in the fiber length direction as disclosed in JP-A Nos. 62-133118 and 62-133118. And the like, various methods have been proposed, such as a method of improving the feeling by fibrillating synthetic fibers, but none of these methods is satisfactory.

On the other hand, various ideas and proposals have been made for false twisted yarns. For example, by making the side yarn longer than the core yarn (by providing a yarn length difference), adding a structural space to the crimp space to increase the amount of deformation of the woven or knitted fabric and diversify the deformation behavior, and to achieve a softer direction A double-layered false twisted yarn aiming at (1) has been proposed. Also, as proposed in Japanese Patent Publication No. 45-18072, a method of producing false twisted and fused yarns to impart a hemp-like crispness, or as proposed in JP-A-63-6123. There are various methods such as a method of producing a mixed fiber fusion-processed yarn, and a method of fibrillating as proposed in JP-A-63-6161. However, it cannot be said that synthetic fibers are given a feeling similar to that of natural fibers.
Giving a texture similar to silk, cotton, and wool was not enough.

[0005]

DISCLOSURE OF THE INVENTION The present invention provides a conventional polyester fiber having a feeling of softness similar to natural fibers such as cotton and silk and a random natural spot between single fibers. As a result of intensive studies with the aim of
The present invention has been reached. That is, the present invention uses any material to obtain the fiber, any structure,
We sought to determine if the conditions should be met.

[0006]

That is, the present invention provides an alkali-soluble polymer component (A) and an alkali-sparingly soluble component (B) in which 85 mol% or more of the constituent units are ethylene terephthalate units or butylene terephthalate units. Wherein the weight ratio of the component (A) to the component (B) constituting the composite fiber is 7:93.
４５45: 55, and the composite cross-sectional shape of the component (A) and the component (B) constituting the composite fiber is substantially the same in the length direction of the fiber. ,
A fiber assembly characterized in that each of the composite fibers as shown in (b) and (c) is contained in the fiber assembly. (A) A composite fiber in which one of the component (A) and the component (B) is a large lump occupying 50% or more of the fiber cross-sectional area and is unevenly distributed in the cross section; None of the components (B) and (B) are present in the cross section as large lumps occupying 50% or more of the fiber cross-sectional area, and the bonding structure of the components (A) and (B) (C) Composite fiber that does not have a radially bonded structure in which the center of radiation is placed in the fiber cross section
Both the component (A) and the component (B) have a fiber cross-sectional area of 5%.
It does not exist as a large lump occupying 0% or more in the cross section, and the component (A) and the component (B) have a radial bonding structure in which the center of radiation is located in the fiber cross section. Composite fiber.

[0007] As the alkali-soluble component used in the present invention, sodium 5-sulfoisophthalate or a derivative thereof (hereinafter sometimes abbreviated as SIP) is 1.5 mol% or more based on the total acid component. A polymer having a molecular weight of 400 with respect to 100 parts of a polyethylene terephthalate-based polyester in which not less than 7.0 mol% is copolymerized and at least 80 mol% of its constituent units are ethylene terephthalate units.
As described above, a polyester to which 10,000 or less polyalkylene glycol is added in an amount of 0.5 to 10 parts is preferable.

[0008] In this component, the SIP homopolymerization system suffers from the drawback that if the copolymerization rate is low, the alkali dissolution rate is low, and if the copolymerization rate is high, the thickening effect is large and the yarn-forming properties are poor. Is eliminated by the addition of That is, if the SIP copolymerization amount is 1.5 mol% or more,
A sufficient alkali dissolution rate can be obtained by the effect of the addition of the polyalkylene glycol, and in the case of a high copolymerization ratio, not only does the processability such as the spinning property be impaired, but also due to its viscosity reducing effect, A remarkable improvement in the alkali dissolution rate can be obtained. However, industrially, the SIP copolymerization rate is preferably 7.0 mol% or less. If the copolymerization ratio is higher than this, it is difficult to obtain a required degree of polymerization due to a thickening effect in the polymerization step.

The amount of polyalkylene glycol to be added depends on the polyethylene terephthalate-based polyester 10
0.5 parts or more and 10 parts or less with respect to 0 parts are preferable. 0.
If the amount is less than 5 parts, the effect of reducing the viscosity and the effect of easily dissolving the alkali are insufficient, and if it exceeds 10 parts, the effect of reducing the viscosity is too large, and troubles such as bleeding out of the polyalkylene glycol during the process are liable to occur. It is because it becomes.

As the polyalkylene glycol used in the present invention, polyethylene glycol, polypropylene glycol, polybutylene glycol and the like can be mentioned. Among them, polyethylene glycol is preferable. Those having a molecular weight of 400 or more and 10,000 or less are preferably used. If the molecular weight is less than 400, bleed-out tends to occur, and the polyester easily reacts with the polyester. When considering the effect of reducing viscosity, the molecular weight of 1
Those exceeding 000 are not preferred. The most preferred molecular weight is 1,000 or more and 8,000 or less. The composition of the alkali-soluble polyester used in the present invention can be modified by using a copolymer component such as isophthalic acid in addition to SIP in a total amount not exceeding 20 mol%. % Is preferable in handling.

The hardly soluble alkali component used in the present invention includes, for example, terephthalic acid, isophthalic acid, naphthalene 2,6-dicarboxylic acid, phthalic acid, α, β- (4-carboxyphenoxy) ethane, and 4,4-dicarboxylic acid. Carboxydiphenyl, aromatic dicarboxylic acid such as pentasodium sulfoisophthalic acid or aliphatic dicarboxylic acid such as adipic acid and sebacic acid or esters thereof, and ethylene glycol, diethylene glycol, 1,4-butanediol, neopentyl glycol, A fiber-forming polyester synthesized from a diol compound such as 1,6-hexanediol or cyclohexane-1,4-dimethanol, wherein 85 mol% or more, particularly 90 mol% or more, of the constituent units are polyethylene terephthalate units or poly (ethylene terephthalate) units. Butylene terephthalate The polyester which is a unit is preferred.

This component may be modified by the third component, but modification of more than 2.5 mol% of SIP alone is not preferable because no difference in alkali solubility can be obtained. Also, addition and kneading or copolymerization of polyalkylene glycol are not preferred for the same reason. In particular, it is preferably less than 1.5 mol. In any case, it is necessary to make the alkali solubility lower than that of the component (A). The polyester may contain a small amount of additives, fluorescent brighteners, stabilizers, ultraviolet absorbers, and the like.

Next, the features of the fiber of the present invention will be described with reference to the drawings. FIG. 1 shows a typical model diagram of a typical cross-sectional shape as an example. The fibers constituting the fiber aggregate of the present invention include (a), (b), and
(C) three types of fibers having a composite shape are included;
(A), (B) and (C) of FIG.
Representative examples of the three composite shapes (b) and (c) are shown. That is, the cross-sectional shape shown in FIG. 1 (a) is a specific example of the above (a), the cross-sectional shape shown in FIG. 1 (b) is a specific example of the above (b), and the cross section shown in FIG. The shape is a specific example of the above (c). Due to the mixture of these various composite shapes, after alkali treatment, some produce a difference in shrinkage strain, and some produce fibril-like ultrafine fibers randomly in the form of branches, and have a soft touch when contacted. Point.

As described above, the composite shapes between the single fibers are different at random, and the shapes are as shown in FIGS.
The mixture represented by the model shapes of (b) and (c) is very irregular due to the alkali treatment, and the natural spots and textures resemble natural fibers, especially
For the first time, it is possible to express the swelling feeling, the softness when touched, and the gentleness of the whole as a fiber assembly. A method for obtaining a fiber having such a composite shape will be described in detail later, but by creating a fiber aggregate having the above-described composite shape, a natural natural fiber-like feel that has never been seen before appears. It became possible to make it.

In general, the fiber having the composite shape of (a) causes an extremely large shrinkage strain, and
The fibers having the composite shape of (a) tend to cause moderate shrinkage strain, the fibers having the composite shape of (b) tend to cause small shrinkage strain, and the fibers having the composite shape of (c) have the above (a). , (B), many small fibrils are generated.

In the composite shape of (a),
One of the components (A) and (B) has a fiber cross-sectional area of 5%.
It is indispensable that a large lump occupying 0% or more is unevenly distributed in the cross section. If there is no large lump occupying 50% or more, a large shrinkage strain is obtained. I can't. In the radially bonded structural fiber as shown in FIG. 1 (c), the components (A) and (B) slightly touch each other at the radial center, and as a result, the component (A) or the component (B) May be seen as a continuous large mass through the radial center,
In such a case, it is needless to say that the component (A) or the component (B) is divided at the radial center. The reason that the conjugate fiber of (c) has a larger shrinkage strain than the conjugate fiber of (b) is that, in the case of the conjugate fiber of (c), the center portion of the radiation usually deviates from the center of the fiber cross section. This is due to shrinkage strain due to the presence in the cross section.

In the present invention, (a), (b),
Regarding the ratio of the fibers in the composite shape of (c), (b) is 3% or more, particularly 5% or more, and (b) is 10% with respect to the total weight of (a), (b) and (c). As described above, it is preferable that 20% or more, particularly (C) be 10% or more, particularly 20% or more. Of course, in the fiber aggregate of the present invention, a composite shape which is a composite fiber of the component (A) and the component (B) but does not belong to the composite shape of the above (A), (B) and (C) is used. May be contained, and fibers other than the composite fibers composed of the components (A) and (B), for example, other synthetic fibers and natural fibers may be added in a large amount.

FIG. 5 shows, by way of example, a cross-sectional structure after the alkali treatment of Example 1 (a weight loss rate of 30%). Next, a production example of the fiber of the present invention will be described. In order to develop the composite-shaped fiber structure of the present invention, the two-component polymer of the alkali-soluble component (A) and the alkali-sparing component (B) is non-uniformly mixed under certain conditions during spinning. It is important that the heterogeneous mixed polymer stream is distributed to the nozzle holes in different states. An example of the spinning method is shown in FIGS. Spinning may be performed using a composite spinneret as shown in FIGS. The polymer melt streams extruded by the separate melt extruders, the alkali easily soluble component (A) and the alkali poorly soluble component (B), respectively, are weighed in predetermined amounts by separate measuring machines, and then filtered by the filtration unit of the sandbox 1. 8 and then mixed under predetermined conditions by a static mixer 5 provided on the mixing plate 2 through each of the filters 6 and radially distributed through the distribution path 7 of the distribution plate 3 to form After the polymer flows into the groove 9 and is filled, it is spun from the die plate 10.

Here, it is very important to appropriately select the number of mixing elements of the static mixer 5 so that the two-component polymer is in a non-uniform mixing state. There are several types of static mixers currently in practical use.
In the case where a static mixer of a type that divides 2 ⁿ layers by passing n elements arranged at 90 ° with blades twisted to the left and right by 90 ° is used, it is preferable that the number of elements be in the range of 3 to 10. When the base plate has a one-hole arrangement, the range of 4 to 8 is more preferable. When the number of elements is 10 or more, the mixing properties of the component (A) and the component (B) become too good, and the mixture becomes close to uniform mixing. Even if the number of elements is set appropriately, after both component polymers start contacting,
If the residence time is too long due to the discharge from the nozzle hole, the viscosity during spinning is greatly reduced, which leads to poor processability, which is not preferable. After both component polymers start contacting,
It is preferable to discharge within 5 minutes, more preferably 3
It is preferable to discharge within minutes. In order to reduce the residence time, the polymer flow path of the distribution plate 3 needs to have an appropriate space.

Another important factor for obtaining the fiber of the present invention is the structure of the distribution plate 3. FIG. 2 is a detailed drawing of the distribution plate viewed from the plane xx ′ of FIG. 2. What is important in this distribution plate is that the heterogeneous mixed flow in which the two-component polymer has flowed out in a multilayer state through the static mixer is shown. To divide the heterogeneous mixed stream radially by dividing it by the number of radial distribution paths. It is necessary that the number of distribution paths be smaller than the number of nozzle holes. Preferably, the ratio between the number of distribution paths and the number of nozzle holes should be in the range of 1: 1.5 to 1: 5. The example in FIG. 3 is an example in which 12 distribution paths are set for a 24-hole nozzle.

The flow of the non-uniform mixing state of the two-component polymer when discharged from the nozzle orifice through the distribution path from the static mixer will be described in more detail by model. For example, the two-component polymer flowing through the four-element static mixer is described below. As shown in FIG. 4, the polymer stream becomes a layered polymer stream of a total of 16 layers including 8 layers of the A component and 8 layers of the B component.
When passing through a distribution plate having two distribution paths, the distribution is performed to each distribution path in the state of the polymer flow of (1) to (12),
(1), (12), (6), and (7) blocks have extremely few layers, and (3), (4), (10), and (9) have the largest number of layers. 2), (5), (8), (11)
Reaches the circumferential groove above the nozzle in an intermediate state. Then, to each block, to the block when two or more nozzle holes are arranged, to the block, when two or more nozzle holes are arranged, the polymer flow from both blocks to the nozzle holes present at the boundary of the block, (1), (12), (6), (7)
1 and (3), (4), (9), and (10), the difference between the mixed states is further expanded, and as a result, FIG.
Fibers in which complex shapes that are complexly different among the single fibers (a), (b), and (c) are mixed can be obtained.

From the (1), (6), (7), and (12) blocks, fibers forming a composite shape similar to (a) or (b) mainly appear, and (3), (4) , (9), (1
0) From the block, fibers having a composite shape centered on (c) mainly appear, and (2), (5), (8), (1)
0) From the block, fibers are obtained in which fibers of a composite shape mainly composed of (b) and those of a composite shape similar to (a) or (c) are slightly mixed. However, since the time-wise flow of the polymer flow constantly flows in the same mixed state, the composite shape having substantially the same shape is maintained in the fiber length direction.

When a static mixer other than Kenix is used, it is needless to say that it is preferable to use a mixer set to a number of elements corresponding to ²ⁿ layer division or more. Toray high-mixer (Hi-Mixer) and Charles & Ross (Charles & Ross)
The number of layers divided when passing n elements is 4 ⁿ layers in a loss ISG mixer manufactured by the company, and it is preferable that the number of elements be 2 or more and 5 or less.

In the present invention, the composite ratio (wt%) of the alkali-soluble component (A) and the sparingly soluble component (B) (A
/ B) needs to be in the range of 7/93 to 45/55, and more preferably in the range of 10/90 to 30/70. This is because it is industrially preferable that the components to be dissolved and removed are as small as possible. However, when the content of the component A is extremely reduced, the area of the component A in contact with the alkaline liquid in the single fiber decreases, and therefore, it takes a long time to remove the component A, and as a result, the weight loss of the component B relatively increases. Therefore, it is preferable that A / B does not fall below 7/93. When A / B is in the range of 7/93 to 45/55, it is desirable to comprehensively judge the desired feeling, processability, yarn properties, and the like, and to select an optimum mixing ratio.

In order to form a desired composite shape, it is preferable to use a polymer having a melt viscosity within an appropriate range. That is, each of the alkali easily soluble component (A component) and the hardly soluble component (B component) is 29%.
Melt viscosity under zero shear stress at 0 ° C is 500 to 7
000 poise and the melt viscosity η _A of the component _A and the melt viscosity η B of the component _B are η _A <η _B η _B ≦ 10 × η _A or η _B <η
_In the case of _A , it is preferable to fall within the range of η _A ≦ 10 × η _B.
If η _A and η _B are η _A <η _B , η _B is at least 10 times η _A and η _B
B <eta For _A eta _A is easily collapsed eta _A and eta balanced melt viscosity difference is too large for _B at the composite spinning to 10 times more eta _B, during spinning HasuMuko, due to screw or the like The number of single yarn breaks and breaks increases, which is not preferable, and at the same time, it is difficult to obtain a desired composite shape. A and B are both 50
If it is less than 0 poise, the spinnability is extremely lowered, which is not preferable. Conversely, even if both A and B have 7000 poise or more, the pressure loss during spinning becomes too large, and the mixed flow of A and B polymers becomes unstable, which is not preferable.

The measurement of the melt viscosity η (poise) under zero shear stress described herein was performed using a Capillograph manufactured by Toyo Seiki Co., Ltd. The shear stress was determined when the shear rate was changed for the polymer in the cell heated to 290 ° C., whereby the apparent melt viscosity was determined. From the relationship between the shear rate and the apparent melt viscosity, the shear stress under zero shear stress was determined. The melt viscosity was extrapolated. As the extrapolation melt viscosity under zero shear stress There are a variety of methods, graph the relationship between the reciprocal (l / η _a) and shear rate (gamma _w) of the apparent melt viscosity here (eta _a) plotted, under assuming l / eta _a value at from the obtained linear relationship gamma _w → 0 and l / eta zero shear stress eta in
Was calculated. In addition, from the viewpoint of easiness in the measurement operation, since the polymer used was a pellet-shaped polymer as the measurement sample, the melt viscosity at the time of actual spinning at the time of fiberization was measured by measuring the [η] of the fiber after fiberization, and the same. Judgment was made with reference to the η measurement data of the polymer pellet of [η].

The fiber aggregate obtained by the present invention may be composed of long fibers or short fibers, and it is needless to say that the same effect can be expected. Further, the fibers constituting the fiber assembly obtained by the present invention may have a shape similar to a pentagon or hexagon by a higher-order processing such as false twist crimping, or may have a three-leaf shape by a nozzle having a modified cross section during spinning. The shape, T shape, 4-lobe shape, 6-lobe shape, 8-lobe shape and other multi-lobe shapes and various cross-sectional shapes are essential. If the fiber satisfies the requirements described so far, the present invention is suitable. It is possible to obtain a fibrous structure having a good feel.

Further, the fiber aggregate obtained in the present invention is used for a two-layer structured yarn, or is subjected to a Taslan process and an interlacing process, and after forming into a fabric, is subjected to an alkali weight reduction process to further increase the swelling feeling. It is more preferable to adjust the hand. Of course, the fiber of the present invention may be used 100%, or the effect of the fiber of the present invention can be obtained even if a part of the fiber of the present invention is used. In the present invention,
Dissolution in alkali includes decomposition and elution, and alkali refers to a solution of KOH or NaOH, particularly preferably an aqueous solution.

The present inventors further studied the alkaline treatment conditions for the fabric containing the conjugate fiber of the present invention, and as a result, reached the following invention. That is, when the fabric containing the conjugate fiber aggregate of the present invention is subjected to alkali treatment, the conjugate fiber is treated so as to have a weight loss rate in the range of the following formula (1). R (%) ≧ 100 × ([A] / {[A] + [B]}) + 3 (1) where R is a weight loss rate in the fiber, [A] and [B] are A components, respectively. It is a composition ratio of the B component.

That is, 3% of the composition ratio of the alkali-soluble component
It is necessary to reduce the weight more. Although the detailed reason for this is not clear, a reaction such as transesterification occurs at the interface between the two components A and B due to the combination of the polyesters, and this is considered to be one of the factors that require a large amount of weight reduction. In addition, the fabric which has been subjected to the alkali treatment is 1
It is more preferable that the cloth is given a fibrous effect by hot water treatment at a temperature of 00 ° C. or higher or by stirring at the time of hot water treatment. The fiber aggregate referred to in the present invention includes multifilaments, staple fiber aggregates, tow-like materials, and multifilament yarns and spun yarns produced using these.

Hereinafter, the present invention will be described with reference to Examples.
It is not limited to this. Example 1 A polyethylene terephthalate (hereinafter abbreviated as PET) polyester ([η]) obtained by copolymerizing 2.5 mol% of SIP.
= 0.49 phenol / tetrachloroethane 1: 1,3
Intrinsic viscosity measured at 0 ° C, melt viscosity: 1700 poise)
Is synthesized by a direct weight method, and after the polymerization is completed, polyethylene glycol having a molecular weight of 6000 is added to 6P. H. R. After adding to the polymerization vessel and kneading under vacuum, the mixture was extruded under nitrogen pressure to obtain chips, which were made into alkali easily soluble components. This is used as an A polymer, and a regular bright polyethylene terephthalate (hereinafter abbreviated as RB-PET) as a B polymer.
([Η] = 0.68, melt viscosity: 1800 poise) was used. Each was extruded by a separate extruder, weighed by a gear pump so that the ratio of A to B became 20: 80% by weight, and then supplied to a spinning pack. A layered divided polymer stream of the component A and the component B was formed by an 8 element static mixer manufactured by Kenix Co., Ltd., and passed through a distribution plate having 12 divided paths.
It was discharged at 90 ° C. and melt-spun at a winding speed of 1000 m / min.

The obtained spun yarn is drawn by an ordinary method,
5d-24f drawn yarn was obtained. The fiberization processability was extremely good. The drawn yarn was used as a warp and a weft to obtain a 1/1 plain woven fabric. The greige plain fabric was desizing, refined and relaxed by a conventional method, and then preset at 180 ° C. Next, alkali treatment (NaOH 20 g / l aqueous solution 90 ° C)
And subjected to a 30% weight reduction process, and dyed under the following conditions. Thereafter, it was dried and set by a conventional method. The obtained plain woven fabric was a pliable and gentle woven fabric having a good feeling. Dyeing method Dye; Dianix Red BN-SE (CI Dis
Perse Red 127) 5% owf Dispersing aid; Disper TL (manufactured by Meisei Chemical Industry) 1
g / l pH adjuster; ammonium sulfate 1 g / l acetic acid (48%) 1 g / l bath ratio; 1:30 1 cc / l temperature; 120 ° C. × 60 minutes reduction washing hydrosulfide 1 g / l amylazine (Daiichi Kogyo Seiyaku) 1 g / l NaOH 1 g / l bath ratio; 1:30 temperature; 80 ° C. × 20 minutes

Examples 2 to 6 The same polymer as in Example 1 was used, Example 2 was a nozzle with a round hole nozzle, and Example 3 had a composite ratio of A / B.
Was carried out under the same conditions as those of Example 1 except that the ratio of A / B was 30/70 and that of Example 4 was 30/70. In Examples 5 and 6, the number of static mixer elements was changed to 4 and 6, and other conditions were the same as in Example 1. In all cases, fabrics having good processability and good feeling were obtained.

Examples 7 to 8 In Example 7, a polybutylene terephthalate having a melt viscosity of 1000 poise was used as the B polymer.
Is the same polymer composition as A polymer and has a melt viscosity of 22.
A polyethylene terephthalate having a melt viscosity of 1200 poise was used as the B polymer, the distribution number of the distribution plate was set to 8, and the other conditions were the same as in Example 1. In all cases, fabrics having good processability and good feeling were obtained.

Example 9 A combination of the same polymer as in Example 1 was melt-spun under the same conditions as in Example 1 except that a round hole nozzle having 24 holes was used. The obtained spun yarn is stretched 3.5 times in a water bath at 75 ° C., then subjected to 7% shrinkage in a water bath at 95 ° C., then mechanically crimped by a conventional method, and then cut into a length of 51 mm. This was used as single-denier 2.5 raw cotton. afterwards,
After blending 2 denier x 51 mm cotton with Sofite N-710 type binder fiber manufactured by Kuraray Co., Ltd. (polyethylene sheath and polyethylene terephthalate as core), a web with a basis weight of 60 g / m ² is prepared. did. Thereafter, a water entanglement treatment was performed at a constant pressure, and a hot air treatment was performed at 150 ° C., and a weight reduction process was performed to produce a nonwoven fabric. The processability from spinning to preparation of the final nonwoven fabric was good and no problem. The hand of the nonwoven fabric was good with natural softness and a gentle touch.

Comparative Examples 1 and 2 The same polymer as in Example 1 was used. Comparative Example 1 had an A / B composite ratio of 5/95, Comparative Example 2 had an A / B composite ratio of 50/50, and the like. Was carried out under the same conditions as in Example 1. However, in Comparative Example 1, there were many slanting directions and screw dropping at the time of nozzle discharge during spinning, and the spinnability was poor. Comparative Example 2 was a ragged woven fabric having no characteristic in hand.

COMPARATIVE EXAMPLE 3 As A polymer, only PE copolymerized with 5 mol% of SIP
T-based polyester chip (melt viscosity: 2500 poise)
, And a drawn yarn was obtained in the same manner as in Example 1 except that the same PET-based polyester chip containing titanium oxide was used as the B polymer. . A 1/1 plain woven fabric of the same standard as in Example 1 was woven with the drawn yarn, and the alkali weight was reduced under the same conditions. The difference between the alkali dissolution rates of the component A and the component B was small, and the weight loss rate reached 53%. The obtained fabric was small in irregularity and had few features.

Example 10 Interlace processing was performed so that the drawn yarn 75d-24f obtained in Example 1 was used as a side yarn and another brand of high shrinkage yarn (wsr = 15%) 50d-24f was used as a core yarn. Thereafter, 250 T / M additional twist was performed to obtain a 1/1 plain woven fabric using the 132d-48f filament yarn as a warp and a weft. This greige fabric was processed in the same manner as in Example 1, and the weight loss rate was 25%.
Finish set in%. The obtained plain woven fabric had a supple, swelling and good texture.

Example 11 The same polymer composition as in Example 1 was used and the winding speed was 3000
The operation was performed under the same conditions as in Example 1 except that the film was wound at m / min and 1900 m / min. The discharge rate was adjusted to obtain 100d-24f spun yarns. The two kinds of spun yarns are combined to have a draw ratio of 2.0, a false twist temperature of 130 ° C.,
Indore false twisting was performed at a false twist number of 1840 T / M to obtain a two-layer false twisted yarn. This false twisted yarn is used as warp and weft as 2
/ 2 twill is created and processed in the same manner as in Example 1,
Finished and set at a weight loss rate of 30%. The obtained fabric was a swelling silky touch fabric having a good feeling. The obtained plain woven fabric was a woven fabric having a soft feeling and bulkiness and a good feeling. Table 1 summarizes the conditions and results of the above examples and comparative examples.

[0040]

[Table 1]

[0041]

As described above, according to the present invention, two kinds of polymers, an alkali-soluble component and a poorly-soluble alkali component, satisfying a specific condition are composite-spun by the above-mentioned special method, and the composite shape is in the fiber length direction. By obtaining special composite fibers that have the same shape but differ randomly between single fibers, and performing alkali weight loss processing under specific conditions, natural spots similar to natural fibers and soft soft texture It is to provide a novel composite filament and a composite staple having the following.

[Brief description of the drawings]

FIG. 1 is a specific example of a cross-sectional shape of three kinds of fibers constituting a fiber aggregate of the present invention.

FIG. 2 is a longitudinal sectional view of a spinning apparatus capable of obtaining a fiber aggregate of the present invention.

FIG. 3 is a cross-sectional view taken along a line xx ′ in the spinning apparatus of FIG. 2;

FIG. 4 is a cross-sectional view schematically showing one example of a composite flow in the process of producing the fiber aggregate of the present invention.

FIG. 5 is a cross-sectional view schematically illustrating an example of the fiber assembly of the present invention after the alkali weight is reduced.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI D06C 29/00 D06C 29/00 Z D06M 11/38 D06M 11/14 // D06M 101: 32 (56) References JP2 -145812 (JP, A) JP-A-63-21921 (JP, A) JP-A-2-169721 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) D03D 15/00, 5/30 D01F 8/14

Claims (3)

(57) [Claims] 1. An alkali-soluble polymer component (A)
And (B) a composite fiber composed of a poorly soluble alkali component comprising ethylene terephthalate units or butylene terephthalate units, and (A) and (B) constituting the composite fiber. ) The weight ratio of the component is in the range of 7:93 to 45:55, and the composite cross-sectional shapes of the component (A) and the component (B) constituting the composite fiber are substantially the same in the fiber length direction. A fiber assembly having a shape, and wherein each of the composite fibers as shown in the following (a), (b) and (c) is contained in the fiber assembly. (A) A composite fiber in which one of the component (A) and the component (B) is a large lump occupying 50% or more of the fiber cross-sectional area and is unevenly distributed in the cross section; None of the components (B) and (B) are present in the cross section as large lumps occupying 50% or more of the fiber cross-sectional area, and the bonding structure of the components (A) and (B) (C) Composite fiber that does not have a radially bonded structure in which the center of radiation is placed in the fiber cross section
Both the component (A) and the component (B) have a fiber cross-sectional area of 5%.
It does not exist as a large lump occupying 0% or more in the cross section, and the component (A) and the component (B) have a radial bonding structure in which the center of radiation is located in the fiber cross section. Composite fiber. 2. An alkali-soluble component (A) in which sodium 5-sulfoisophthalate or a derivative thereof is copolymerized in an amount of 1.5 mol% or more and 7.0 mol% or less based on all acid components. And 0.5 to 10 parts of a polyalkylene glycol having a molecular weight of 400 to 10,000 is added to 100 parts of a polyethylene terephthalate-based polyester in which 80 mol% or more of its constituent units are ethylene terephthalate units. The composite fiber aggregate according to claim 1, which is a polymer. 3. A fabric comprising the composite fiber aggregate according to claim 1, wherein the fiber is subjected to an alkali treatment so that the fiber has a weight loss rate in the range of the following formula (1). Processing method. R (%) ≧ 100 × ([A] / {[A] + [B]}) + 3 (1) where R is a weight loss rate in the fiber, and [A] and [B] are A components, respectively. , B component ratio.