JPH1037022A - Random latent crimpable yarn - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a random latent crimpable yarn suitable as a raw material for clothing giving a sense of fulfillment sensing both good swollen and compacted states, excellent in tension and stiffness touches and extremely soft in surface touch. SOLUTION: This random latent crimpable yarn comprises a polyester composite yarn comprising multifilaments. The multifilaments comprises two kinds of polyester components different in shrinkage degrees from each other and have a multilayered structure continued in the filament axial direction. The polyester composite yarn has random latent shrinkability and random latent crimpability, and has the following characteristics. The whole shrinkage degree of the multifilaments is at least 40% on a boiling water treatment, and the rate of the crimping shrinkage degree to the whole boiling water shrinkage degree of the multifilaments is 50-90%. The difference between the maximum linear shrinkage degree and the minimum linear shrinkage degree among the filaments composing the multifilaments is at least 15% or larger.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a randomly crimped high-shrinkable fiber suitable for producing high-grade garment materials which have a fullness of swelling and a sense of denseness, are excellent in firmness and firmness, and have an extremely soft surface touch. About.

[0002]

2. Description of the Related Art Natural fibers, such as wool, silk, and cotton, have a fineness, shape,
It is characterized by variations in structure or physical properties such as crimps. Due to such variations in structure and physical properties, the swelling is large and the texture is good compared to synthetic fiber products.

[0003] Various attempts have been made to blend two or more yarns having different shrinkage ratios or to achieve bulkiness using false twisted yarns in order to express the characteristics of natural fibers even in synthetic fibers. Have been. In recent years, composite yarns that have been made more complex and have been false-twisted with mixed fibers of multiple fibers with different fiber (elongation) degrees and different shrinkage mixed yarns that use highly shrinkable fibers obtained by modifying a copolymer have been developed. Efforts are being made to make the fabric obtained by combining with other technologies, such as self-extending yarn blending that forms loops, more and more sensitive to natural fibers. Have been. However, in the case of such a processing method, the improvement of the fabric by giving a swelling to the obtained woven or knitted fabric is mainly performed, and as in the present invention, the fabric has a sense of fulfillment that senses denseness at the same time as swelling, and the surface touch is extremely low. No new soft materials have been obtained.

According to the technique of mixed shrinkage yarns, it has been successful to improve the sense of denseness of the fabric by the advancement of the high shrinkage yarn, but the swelling becomes large, but the fabric which is the object of the present invention is fulfilled. The feeling is hard to come out. Next, when only the high shrinkage fiber was used, the voids between the fibers in the fabric were reduced, the feeling of swelling was small, the touch became rough and hard, and the surface condition was plain and unchanged and rough. It's just something.

[0005] In addition, the processing yarn technology centering on false twisting is intended to give wool-like bulkiness to a filament fabric such as polyester, and the object of the present invention is to enhance the fineness. It doesn't try to get a feeling.

A more recent proposal has become more complicated. For example, JP-B-63-30421 discloses a method of producing a crimped yarn in which polyester filaments having different crimp rates are mixed. At this time, a side-by-side type composite fiber having an intrinsic viscosity difference between polymer components is formed, and filaments having substantially the same fineness having different composite ratios are mixed and crimped by a heating fluid pushing nozzle. Different crimped blended yarns are disclosed. However, in this method, not only does the manufacturing process become complicated or complicated due to the mixing of separately obtained yarns, but also the filament obtained by this method has a small change in the crimp waveform, and the woven and knitted fabric can be used. In this case, a sufficient swelling feeling cannot be given.

In Japanese Patent Application Nos. Hei 3-220331, Hei 4-136209 and Hei 4-340008, a multi-shrinkage mixed fiber is disclosed in Japanese Patent Application No. 22221/1990.
In Japanese Patent Application Laid-open No. 4 (Kokai) No. 4, a mixed fiber composed of filaments having different composition ratios of two kinds of polymers is proposed. However, in the former, the difference in shrinkage between filaments is not sufficient, and only the improvement of the inadequate use of different shrinkage mixed yarns is improved, and in the latter, the swelling feeling due to crimping is simply improved. This is far from the soft fabric with a rich surface touch, which is the object of the present invention.

[0008]

DISCLOSURE OF THE INVENTION The present invention is directed to a fabric having a new sensibility, which has not been obtained in conventional synthetic fiber fabrics and natural fiber fabrics, that is, a fabric full of firmness and waist feeling and fullness of denseness. In order to provide a material having a highly random crimp suitable for providing a fabric having a very soft surface touch and a highly random shrinkable material,
And it aims at providing the said material easily industrially and cheaply.

[0009]

Means for Solving the Problems As a result of intensive studies, the present inventors have completed the present invention. First, (1) in order to develop a good crimp, a polyester (A component) having a large shrinkage and a polyester (B component) having a small shrinkage are joined to a multilayer laminate type, and the shrinkage characteristics of the A component and the B component are obtained. The crimping performance was developed by utilizing the difference between the two. In addition, by forming an aggregate of filaments in which the composite ratio of the component A and the component B in each filament is irregularly different, the crimp can be randomized, and a swelling feeling and a feeling of fulfillment, which have never existed before, can be provided.

Next, (2) the heat shrinkage characteristics of the multilayer laminated filaments were examined, and the heat shrinkage characteristics for exhibiting good crimping characteristics were clarified.

Further, (3) by setting the high shrinkage component to the same ratio as the low shrinkage component, or rather, to a large value, the value of the residual thermal stress is increased, the shrinkage ratio of the woven fabric is increased, and the structure is densified. , A firm feeling, firmness and firmness can be obtained. On the other hand, increasing the compounding ratio of the high shrinkage component reduces the number of filaments containing a remarkably large low shrinkage component in each filament constituting the multifilament. As a result, the number of loops that emerge on the surface of the fabric is reduced, and the touch becomes extremely soft.

That is, the present invention has a multilayer laminate structure composed of two kinds of polyester components having different shrinkage rates and continuous in the fiber axis direction, the total boiling yield of multifilaments by boiling water treatment is at least 40%, and the fiber A random latent form in which the ratio of the crimp shrinkage to the total boiling yield is 50% to 90%, and the difference between the maximum value and the minimum value of the linear shrinkage ratio among the filaments constituting the multifilament is at least 15% or more. It is a polyester composite fiber having shrinkage and latent crimpability.

A second aspect of the present invention is characterized in that the ratio of the high shrinkage polyester component to the low shrinkage polyester component is 1/1 to 2.5 / 1 (weight ratio) in the whole multifilament. This is one polyester composite fiber.

A third aspect of the present invention is a first or second polyester, wherein the number of crimps of all the single filaments constituting the multifilament after the boiling water treatment is at least 20 / inch. It is a composite fiber.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION The latently crimped yarn referred to in the present invention refers to a filament having a multilayer laminated structure of the A component and the B component in the cross section of a single filament. It is preferable that the bonding form of the filament having a multilayer laminated structure in any cross section is uniformly continuous along the longitudinal direction of the filament, but a part thereof may include a discontinuous structure. Yarns with a uniform and continuous structure are spun,
It is preferable because stretching operability is good and no drawbacks appear after the product is obtained. Here, the bonding mode refers to a mode of bonding the A component and the B component. The multilayer structure refers to a layered structure of at least two layers, preferably two to ten layers, more preferably three to seven layers, in which the component A and the component B are joined. An example is shown in FIG.

The cross-sectional shape of the latently crimped yarn is a round cross-section as long as it can form and maintain the bonded form of the component A and the component B and can express the crimping performance aimed at by the present invention. , A triangular cross section, a Y cross section, a U cross section, a flat cross section or the like may be used, and can be properly used depending on the application and purpose. In particular, those having irregular cross sections such as a triangular cross section, a Y cross section, a U cross section, and a flat cross section are preferable.

Among them, the degree of irregularity (perimeter / diameter) is 3.2 or more, preferably 3.5 to 6.0, and more preferably 3.7 to 4.5. Here, the diameter represents a circle equivalent diameter (that is, a diameter of a circle corresponding to the same area). By selecting such a degree of irregularity, the effects of the irregularly shaped cross section and the multilayer laminated structure act synergistically to further increase the random shrinkage and random crimpability between filaments, and to increase the swelling between fibers. And reduce frictional force.
This makes it possible to improve the softness, softness, firmness, and firmness of the fabric, and is preferable for expressing a sense of fulfillment and a soft touch on the surface, which is unique to the present invention.

The total boiling yield (SH1) is defined as the shrinkage ratio due to crimping (hereinafter referred to as crimp shrinkage ratio (SH3)) and the shrinkage ratio not due to crimping (hereinafter referred to as linear shrinkage ratio (SH2)). It is sum. The method of calculating these values will be described below.

The drawn fiber (multifilament) is measured for a certain length (for example, 30 cm), and a mark is made on the fiber at a certain length (for example, 20 cm: L0). Next, take care not to entangle the fibers.
For 15 minutes in hot water. After the treatment, the fiber is taken out of hot water while taking care not to stretch, and the surface of the fiber is drained off with a tissue paper or the like. After air-drying, a 0.5 mg / d load was applied to the end of the fiber, and the fiber was suspended vertically.
Measure 1). Further increase the weight to 0.5 g / d and measure the length (L2).

[0020]

## EQU1 ## Total boiling yield: SH1 = [(L0-L1) / L
0] × 100 (%)

[0021]

## EQU2 ## Linear shrinkage: SH2 = [(L0-L2) / L
0] × 100 (%)

[0022]

## EQU3 ## Crimp shrinkage: SH3 = SH1-SH2 (%)

In the present invention, the total boiling yield is at least 40
%, Preferably 50% to 80%. Total boiling yield is 40
If it is less than%, it is not possible to obtain a cloth which is excellent in firmness and waist feeling and which is full of feeling of denseness and which has an extremely soft surface touch as intended in the present application.

The most important feature of the present invention is the bonding state of two kinds of polymers between each filament constituting the fiber,
The joining ratio differs one by one, and therefore the state and physical properties of the fiber differ for each filament. Specifically, the difference between the maximum value and the minimum value of the linear shrinkage between the filaments constituting the multifilament (hereinafter referred to as total aberration) is at least 15% or more, preferably 20% or more. At a value where the total aberration is less than 15%, denseness is exhibited,
The difference in shrinkage between the filaments constituting the fiber is small, and the desired sufficient swelling, firmness, waist, and surface touch are not obtained. The linear shrinkage of each filament is measured by measuring the length of each filament. In this case, the measurement is performed with no load but without any slack.

In particular, the variation rate of variation between filaments [(total aberration / average value of linear shrinkage rates of constituent single yarns) × 1]
00] is 50 to 200%, which is more preferable in terms of texture and natural touch.

In particular, the fluctuation of the shrinkage rate of each filament of the fiber of the present invention is generally determined by the bonding ratio of the two kinds of polymers constituting the fiber. A filament having a high ratio of the high shrinkage component has a high shrinkage. In such a filament having a large polymer composition ratio, crimp generated in the filament is reduced. Therefore, when a filament having a low shrinkage has a low shrinkage ratio and a small number of crimps, it is expressed as a loop having a gentle crimp on the surface of the fabric when formed into a fabric. Further, as described above, the surface of the multifilament as a whole has a relatively large number of high-shrinkage components, so that the number of loops on the surface is relatively small, so that the surface touch becomes extremely soft. The loop as it is is very useful for improving the surface touch, but if the loop is cut by sanding the surface of the fabric after forming the fabric, a more favorable soft texture can be achieved.

In order to obtain the cloth intended for the present invention,
In addition to simple shrinkage in the longitudinal direction of the fiber, crimping in the lateral direction of the fiber due to crimping is necessary. For this purpose, it is preferable that the value of the crimp shrinkage relative to the total shrinkage be 50 to 90%. . If it is less than 50%, the swelling in the transverse direction of the fiber (the thickness direction of the fabric) becomes insufficient, and the stiffness, waist, and swelling are not sufficient.

The fiber of the present invention is a composite fiber composed of a high shrinkage component and a low shrinkage component, and each fiber is crimped by heating treatment such as boiling water treatment. In order to obtain the desired texture, the number of crimps of all the single filaments constituting the multifilament after the boiling water treatment is at least 2
It is preferably 0 / inch, more preferably at least 25 / inch. As an example, a crimped state of the fiber of the example is shown in FIG. The number of crimps was measured in the same manner as in the measurement of the total shrinkage by 0.5 m of the yarn subjected to the boiling water treatment.
This was done by cutting to a length of 1 inch under a load of g, carefully separating into single filaments and counting the number of crimps.

Further, it is more preferable that the number of crimps after the boiling water treatment is different between the respective filaments, rather than being the same for all the filaments. In other words, the variation in the number of crimps between the filaments after the boiling water treatment is preferably 50 to 50%.
200%. As a result, a large number of minute natural voids are formed between the fibers even after the fabric is formed, and a feeling of swelling and a sense of fulfillment are produced.

Although the composite fiber of the present invention develops crimp by heat treatment such as boiling water treatment, the larger the force required for elongating the developed crimp, the more stable the fiber is. For example, 30 mg / d If it is to the extent, a sufficiently good swelling can be exhibited even in the case of fabric.

The high shrinkage polyester component (hereinafter abbreviated as A component) used in the present invention is a polyester having a large heat shrinkage property, and usually a modified polyester is used. For example, a dicarboxylic acid component containing terephthalic acid or 2,6-naphthalenedicarboxylic acid as a main component, and ethylene glycol-
When producing an aromatic polyester mainly containing toluene as a third component, a general formula is used as a third component.

Embedded image (Wherein, R represents a hydrogen atom or an alkyl group such as methyl, ethyl, n-propyl, iso-propyl, n-butyl, t-butyl group, etc.) or an aliphatic ester thereof, or General formula

Embedded image (In the formula, X represents a hydrogen atom or an alkyl group such as methyl, ethyl, n-propyl, isopropyl, n-butyl, t-butyl group, l and m represent integers, and B represents a hydrogen atom or a methyl group. Or a compound having a bisphenol A skeleton represented by the following general formula:

Embedded image (Wherein, Y represents a hydrogen atom or an alkyl group such as methyl, ethyl, n-propyl, iso-propyl, n-butyl, t-butyl group, l and m represent integers, and B represents a hydrogen atom or a methyl group. The compound having a bisphenol S skeleton represented by the following formula is copolymerized.

The amount of the third component to be copolymerized with the component A is usually 3 to 30 mol%, preferably 5 to 20 mol%.
It is. If it is less than 3 mol%, sufficient shrinkage performance cannot be obtained, and the desired bulkiness and swelling cannot be achieved.
On the other hand, if it is more than 30 mol%, not only the mechanical properties or thermal properties of the polymer deteriorate, but also the shrinkage is too high to increase the coarse hardness, or the polyester added with the copolymer component becomes too deeply dyed. The uniform dyeing of the woven or knitted fabric is inferior. Particularly, by using a modified polyester obtained by copolymerization of Chemical formulas 2 and 3, the glass transition temperature (Tg) of the polymer can be increased and the heat resistance of the fiber itself can be improved, which is more preferable.

The low shrinkage polyester component (hereinafter abbreviated as component B) used in the present invention must have a lower boiling yield than the polyester component used in component A, and therefore have a lower modification rate. For example, when an aromatic polyester composed of a dicarboxylic acid component containing terephthalic acid or 2,6-naphthalenedicarboxylic acid as a main component and a glycol component containing ethylene glycol as a main component is produced by a known method, Polymerization as it is without adding three components,
Alternatively, the compound to be copolymerized with the component A is a copolymer polyester which is usually 3 mol% or less, preferably 5 to 10 mol%, less than the compounding amount of the component A.

When a polyester obtained by copolymerizing the third component with both the A component and the B component is used, if the difference between the added amounts of the A component and the B component is less than 3 mol%, the shrinkage characteristics of the A component and the B component are reduced. Sufficient shrinkage difference and crimp rate difference cannot be obtained due to the difference in the fiber, and the desired performance and texture are fully exhibited without the variation in the shrinkage ratio between each filament in the fiber and the variation in the crimp. Can not.

Pigments, matting agents, fluorescent whitening agents, ultraviolet absorbers, antioxidants, antistatic agents, organic amines, organic carboxylic acid amides, etc., during the production or molding of the polyesters of component A and component B. Various ether bond inhibitors may be used as necessary.

The joining ratio of the component A / component B is not particularly limited as long as the object is achieved, but is preferably 2.5 / 1 to 1/1 (weight ratio, hereinafter the same) as the whole multifilament, more preferably 2 / 1 to 1.2 / 1. Whether this value is greater than 2.5 / 1 or less than 1/1,
According to the present invention, it is difficult to obtain a new-feeling fabric that has a fullness of feeling the fineness at the same time as the moderate swelling, and is rich in firmness and firmness, and the surface touch is extremely soft.

That is, since the ratio of the component A in the fiber is larger than that of the component B, the filaments shrink in the fabric processing step, especially in the relaxation treatment after refining and alkali weight reduction, which is important for the appearance of texture, and in the dry heat setting. The difference in the percentage and the difference in the crimp are well expressed, and the fabric has a firmness, stiffness, swelling and a desirable fluffiness on the surface of the fabric.

As described above, the ratio of the A component and the B component between the filaments constituting the fiber and the structure of their laminations are different, and particularly, the ratio of the B component (low shrinkage component) is large and the number of layers is small. In this case, both the number of crimps and the shrinkage ratio become small, and these filaments float on the surface of the fabric in the fabric, resulting in minute fluff. Conversely, for filaments containing a large amount of the A component (high shrinkage component), the shrinkage increases simultaneously with the number of crimps. Develop dispersed voids.

Here, the bonding ratio is an average value of the area of the A component and the B component in the cross section of the fiber in all the filaments in the fiber, and the A component and the B component are measured by separate gear pumps at the time of spinning. Can be easily controlled.

As a method of forming a laminated structure of the component A and the component B on each filament, a method which has been conventionally proposed by us can be preferably used. For example, a kneading type distribution plate disclosed in JP-B-47-9533 and a static kneading element disclosed in JP-A-59-100717 can be used. As the static kneading element, for example, a "static mixer" manufactured by Kenix, an ISG mixer manufactured by ROSS, and a mixing element manufactured by Sulzer can be used.

The polymer flow passing through such a static kneading element is split into the square of the number of elements. Here, usually 1 to 4 stationary kneading elements are used. With this element, both A and B components are laminated in 2 to 16 layers. The polymer melt in which a plurality of components A and B are laminated is extruded into the air from a number of spinning discharge holes to form a filament. Therefore, each filament is composed of both A and B components,
~ 16 layers, preferably 2 ~ 10 layers, more preferably 3 ~
There are seven layers. When the number of layers increases, the fluctuation between the shrinkage characteristics and the crimp characteristics between the filaments decreases, and the desired texture and performance are hardly obtained.

In spinning, a mixture obtained by mixing the above two types of polymers in a multilayer by a static mixing element incorporated in a die is discharged and wound from the fine holes of the die. The winding method is
A conveyor system with a normal speed of up to about 1500 m / min may be used, a POY system with a speed of about 3000 m / min may be wound, and a high-speed spinning (HOY) of 5000 m / min or more.
It may be wound by a method. The wound fiber is subsequently drawn. It is of course possible to simultaneously draw (SPD) in the spinning stage.

By using such a static kneading element, the ratio of the A component / B component and the laminated structure of each filament are greatly different as shown in FIG. 1, but such a polymer in the length direction of each filament is different. The ratio and the laminated structure were hardly changed, and the deterioration of the operability which was a fundamental problem in the conventional polymer blend spinning was able to be largely improved.

For the stretching, a combination of a heating roller and a heating plate, which is generally performed generally, can be suitably used, but stretching by a plurality of heating rollers may be used. In the case of a combination of a heating roller and a heating plate, drawing is performed by a heating roller and heat setting is performed by a heating plate to provide yarn quality and crimp characteristics that match the purpose. For example, the stretching temperature is usually 60 to
120 ° C, preferably 65-100 ° C, more preferably 70-90 ° C. Further, the temperature of the heating plate is usually set to be higher than the drawing temperature by 10 to 50 ° C., but is usually 120 ° C., preferably at most 100 ° C., in order to keep the total shrinkage of the fiber at a target value. After the stretching, for example, the film may be further stretched at a stretching temperature of not more than 1.1 times at a magnification of at most 1.1 to improve the crimp appearance.

It can be said that the fabric and knitted fabric can provide a good effect even in the same structure as the normally used woven or knitted fabric, can exhibit a soft touch, and can produce a new sense of fabric at low cost. There are benefits. Of course, a higher texture and touch can be exhibited by using as a component of the different shrinkage mixed yarn or the composite processed yarn, or by making it a more complicated weave structure.

The processing of woven and knitted fabrics can be performed by the same processing as the processing of ordinary fibers. For example, it is a series of steps such as refining, alkali weight reduction, relaxation, dyeing, heat setting, and the like, and if necessary, resin processing or the like may be performed.

[0047]

The present invention will be described in detail with reference to the following examples. In the examples, “parts” means “parts by weight” unless otherwise specified, and “%” means “% by weight” unless otherwise specified. The intrinsic viscosity [η] was determined by a conventional method at 20 ° C. in a mixed solvent of phenol / tetrachloroethane = 6/4. Scanning electron microscope (hereinafter referred to as SEM) measurements were performed with a scanning electron microscope manufactured by Akashi Seisakusho. The number of crimps was converted into the number per inch from a micrograph taken with a stereo microscope manufactured by Olympus Corporation.

Examples 1 to 11 and Comparative Examples 1 and 2 As the low shrinkage component (A component), ordinary polyethylene terephthalate having [η] = 0.63 (hereinafter, usually referred to as polyester) was used. High shrinkage component (B component)
A modified polyester obtained by copolymerizing polyethylene terephthalate with 5 mol% of isophthalic acid as an acid component and 5 mol% of bisphenol A (2EO adduct) as an alcohol component was used.

The temperature was set to 2 at the extruder so that the joining ratio of the component A and the component B was mixed at the weight ratios shown in Table 1.
After melting at 90 ° C., each is measured by a separate gear pump and sent to a spinneret. Inside the spinneret, a static kneading element (3 Kenics mixing elements) is passed,
The components A and B are mixed so as to have a multilayer structure, and then melt-spun from 36 equal-length Y-shaped spinning pores to form a mixture.
Winding was performed at a speed of 0 m / min to obtain an undrawn yarn. The cross-section of the obtained undrawn yarn had an onigiri-shaped, almost triangular shape with rounded corners. The yarn was drawn 3.6 times at a draw rate of 7
The film was stretched with a roller heater at 75 ° C. at 30 m / min.
50 denier (hereinafter referred to as d) / 36 filaments (hereinafter referred to as f) after heat setting with a hot plate (PLH) shown in
(Examples 1 to 11 and Comparative Examples 1 and 2) were obtained. The measured values of the total boiling yield, direct yield, crimp shrinkage, the ratio of the crimp shrinkage to the total boiling yield of these fibers, and the evaluation results of the feeling of fullness, fullness, firmness, firmness, and soft touch Are shown in Table 1.

When the cross section of the fiber is observed with a microscope,
As shown in the figure, the composite fiber had a multilayer structure of at least two layers and at most about seven layers. What is characteristic is that each fiber has a different composite shape (composite ratio, composite shape, multi-layered state, etc.). Table 1 shows the physical properties of the obtained drawn yarn.

Comparative Example 3 Using normal polyethylene terephthalate (η) = 0.63 (hereinafter usually referred to as polyester), 36 isometric Y-types at a spinning temperature of 290 ° C. and a spinning speed of 1000 m / min. Was melt spun from the spinning pores of No. 1. The cross-section of the obtained undrawn yarn had an onigiri-shaped, almost triangular shape with rounded corners. The yarn was drawn at a draw ratio of 3.6 times at a drawing speed of 730 m / min with a roller heater at 84 ° C., set with a plate heater at 140 ° C., and set at 50 denier (hereinafter referred to as d). ) / 36 filaments (hereinafter referred to as f) were obtained. After the obtained drawn yarn was subjected to hot water treatment, a crimp shrinkage value or a linear shrinkage value was obtained. The yarn after the boiling water shrinkage was an ordinary fiber without any crimping. The total boiling point was 8.3%, there was no crimp shrinkage, and the linear shrinkage was 8.3%.

Comparative Example 4 Using regular polyethylene terephthalate (η) = 0.63 (hereinafter, usually referred to as polyester), 36 isometric Y-types at a spinning temperature of 290 ° C. and a spinning speed of 1000 m / min. Was melt spun from the spinning pores of No. 1. The cross-section of the obtained undrawn yarn had an onigiri-shaped, almost triangular shape with rounded corners. The yarn is drawn at a draw ratio of 3.6 times at a drawing speed of 730 m / min with a roller heater at 84 ° C., and set with a plate heater at 100 ° C. to obtain a 25d / 18f multifilament. I got In addition, bisphenol A (2EO adduct) was used as an alcohol component of [η] = 0.63 at 5 mol%.
Using a copolymerized modified polyester, a spinning temperature of 28
Melt spinning was performed from 36 equal-length Y-shaped spinning pores at 5 ° C. and a spinning speed of 1000 m / min. The cross-section of the obtained undrawn yarn had an onigiri-shaped, almost triangular shape with rounded corners. The yarn was drawn at a draw ratio of 3.6 times at a drawing speed of 730 m / min.
Stretched with a roller heater at 90 ° C and a plate heater at 90 ° C.
It was set with a tar to obtain a 25d / 18f multifilament.

The two types of fibers were further combined into two yarns by a rewinding machine to obtain a different shrinkage mixed yarn of Comparative Example 4.

In order to evaluate the heat shrinkage characteristics of the fibers used for the mixed fiber, each stretched yarn before being combined was subjected to a hot water treatment, and then a crimp shrinkage value or a linear shrinkage value was obtained. In each case, the yarns after the boiling water shrinkage were ordinary fibers with no particular crimp.
The total yield of the yarn on the low shrinkage side was 10.9%, there was no crimp shrinkage, so the linear shrinkage was also 10.9%, and the total yield on the high shrinkage side was 34.3%. Was.

Comparative Example 5 The components A and B in Example 1 were set to 3/2, the kneading mixing element of the static kneading element in the spinneret was set to five, and a hot plate on which the multifilament was heat-set after drawing was used. Except that the temperature was changed to 110 ° C., 5
A 0d / 36f multifilament was obtained.

Table 1 shows the physical properties of the multifilaments of Examples 1 to 11 and Comparative Examples 1 to 5 obtained by the above method.
Further, in order to examine the distribution of the crimped state by unraveling a single filament constituting the multifilament of Example 3,
An SEM measurement was performed. The result is shown in FIG.

[0057]

[Table 1]

Evaluation of Fabric (1) Plain weave was prepared by using the multifilaments obtained in Examples 1 to 11 and Comparative Examples 1 to 5 for warp and weft.
After scouring at 0 ° C, relaxing at 95 ° C and heat setting at 180 ° C. The heat setting was carried out by stretching 1 to 2% for wrinkle growth in both processes. After subjecting the fabric to a 15% alkali weight loss, it was dyed beige at 130 ° C. using a disperse dye and then finished set at 170 ° C.
The texture of each of the obtained fabrics was evaluated by a skilled worker. The evaluation was made on the feeling of swelling, softness, firmness, and firmness. A particularly excellent thing was marked with ◎, an excellent thing was marked with ○, a slightly poor thing was marked with Δ, and an inferior thing was marked with x. Similar evaluations were made for the overall evaluation. The results are shown in Table 2.

Evaluation of Fabric (2) The multifilaments obtained in Examples 1 to 11 and Comparative Examples 1 to 5 were used as wefts, and plain weaves (taffeta) were woven using ordinary polyester fibers for the warp. After refining,
After a 15% alkali weight loss, 130 using a jet dyeing machine.
After relaxing at ℃, it was set at 180 ° C. dry heat. The texture of the finished fabric was evaluated by the touch of a skilled person. The evaluation was made on the feeling of swelling, softness, firmness, and firmness. A particularly excellent thing was marked with ◎, an excellent thing was marked with ○, a slightly poor thing was marked with Δ, and an inferior thing was marked with x. Similar evaluations were made for the overall evaluation.
The results are shown in Table 2.

[0060]

[Table 2]

[0061]

The latent latent crimped yarns of the present invention have good latent shrinkage and potential crimpability, and all of them have random variations among the filaments in the fiber. When made into a fabric, a good firmness, firmness, swelling and a very natural sense of fulfillment can be exhibited.

Further, since the fiber itself has a very large degree of dispersion in shrinkage characteristics and crimp characteristics as described above, it does not require a complicated fiber structure or woven structure, and has high quality and excellent sensitivity. It can be made into woven and knitted fabrics and has excellent cost performance. Moreover, since the shrinkage and the crimping ratio are greatly different between the filaments constituting the fiber, even in the case of fabric, the comfort, comfort, and workability such as sewing are greatly improved in addition to the above-mentioned characteristics. Stretch properties can also be imparted.

[Brief description of the drawings]

FIG. 1 shows an example of a form of a composite structure according to the present invention.

FIG. 2 is an example of an SEM photograph showing a state of crimping after a boiling water treatment, and shows a fiber shape.

FIG. 3 shows an example of the distribution of the total boiling point value of each of the filaments of the yarn of the present invention (Example 3).

[Explanation of symbols]

 a. High shrinkage component b. Low shrinkage component

Claims (3)

[Claims] 1. A multifilament having a multilayer laminate structure composed of two types of polyester components having different shrinkage rates and continuous in the fiber axis direction, wherein the total boiling yield of the multifilament by boiling water treatment is at least 40% and the total multifilament is multifilament. The ratio of the crimp shrinkage ratio to the boiling yield is 50% to 90%.
%, And the difference between the maximum value and the minimum value of the linear shrinkage rate between the filaments constituting the multifilament is at least 1
A polyester composite fiber having random latent shrinkage and latent crimpability of 5% or more. 2. The ratio of the component (A) having a higher shrinkage ratio to the component (B) having a lower shrinkage ratio is A / B = 1/1 to 2.5 / 1 (weight ratio) in the whole multifilament. Claim 1
Polyester composite fiber. 3. The number of crimps of all the single filaments constituting the multifilament after the boiling water treatment is at least 2
The polyester composite fiber according to claim 1 or 2, wherein the number is 0 / inch.