JP2001064829A - Ultrafine polyester fiber, combined filament yarn and cloth therefrom - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ultrafine polyester fiber capable of forming cloths, such as a high-density woven and knitted fabric, excellent in resiliency and form retention, although the woven and knitted fabric is thin, light and soft, and to provide combined filament yarns and cloths therefrom. SOLUTION: This ultrafine polyester fiber is obtained from a conjugate fiber of the ultrafine fiber-generating type, wherein the fiber has the following characteristics (A): (1) the density is 1.335-1.360 (g/cm3); (2) the degree of crystallization is 21-26%; (3) the crystalline size is 1.4-2.2 nm at the Miller indices of (010), 1.4-2.5 nm at the Miller indices of (100), and 1.6-3.5 nm at the Miller indices of 1 with a bar, 0 and 5 [hereinafter, referred to as (-105)]; (4) the orientation of the crystalline region is 75% or less at the Miller indices of (010) and 85% or less at the Miller indices of (-105); and (5) the orientation of the amorphous region is 0.15-0.4, the hot-water shrinkage percentage is 0-35% and the dry-heat shrinkage percentage is 0-35%.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention is thin, light,
The present invention relates to an ultrafine polyester fiber, a mixed fiber, and a fabric capable of obtaining a fabric such as a high-density woven or knitted fabric having excellent resilience and shape retention even though it is a soft woven or knitted fabric.

[0002]

2. Description of the Related Art Conventionally, as a woven or knitted fabric using ultra-fine fibers, as is known from Japanese Patent Publication No. 64-6311, not only ultra-fine polyester fibers alone but also nylon is used. Both could not be dyed properly. This is because the disperse dye for dyeing polyester contaminates nylon. In addition, nylon 6 and nylon 66 have problems such as expansion and contraction with respect to moisture or water and lacking dimensional stability.

[0003]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a thin, light and soft woven and knitted fabric made of ultrafine polyester fiber containing no nylon, yet having high resilience and excellent shape retention. An object of the present invention is to provide an ultrafine polyester fiber, a mixed fiber, and a fabric from which a fabric such as a woven or knitted fabric can be obtained.

[0004]

The polyester fiber of the present invention which achieves the above object has the following constitution. That is, the present invention provides: [1] An ultrafine polyester fiber, wherein the ultrafine polyester fiber obtained from the ultrafine fiber-generating conjugate fiber has the following property (A). Characteristics (A) (1) Specific gravity is 1.335 to 1.360 (g / cm ³ ) (2) Crystallinity is 21 to 26% (3) Crystal size is 1.4 in plane index (010)
To 2.2 nm, and 1.4 to 2.2 in plane index (100).
5 nm, 1.6-3.5 nm in plane index (described as -105 after 1 bar 05) (4) Crystal orientation degree is 75% or less on 010 plane, 85% or less on -105 plane, and (5) amorphous The degree of orientation is 0.15 to 0.4 and the shrinkage ratio of hot water is 0.
-35% and a dry heat shrinkage of 0 to 35% [2] The ultrafine polyester fiber having the characteristic A has an amorphous orientation degree of 0.15 to 0.3 and a hot water shrinkage of 0 to 10%. And the dry heat shrinkage is from 0 to 10%.

[3] A polyester mixed yarn, wherein the ultrafine polyester fiber of [1] or [2] is mixed with another ultrafine polyester fiber.

[4] A polyester mixed yarn, wherein the ultrafine polyester fiber of [1] or [2] and a polyester fiber having a single fiber fineness of 1 to 40 denier are mixed.

[5] The polyester blended yarn according to any one of [1] to [4], wherein the ultrafine polyester fiber is obtained by removing one component from a sea-island composite fiber.

[6] The polyester mixed fiber according to any one of [3] to [5], wherein the mixed fiber is formed by air entanglement.

[7] The mixed fiber according to [3], wherein the other ultrafine polyester fibers are ultrafine polyester fibers obtained by removing one component from ultrafine fiber-generating conjugate fibers.

[8] A fabric comprising at least the ultrafine polyester fiber or the polyester mixed yarn according to any one of [1] to [7].

[9] A fabric using at least the ultrafine fiber-generating conjugate fiber according to any one of [1] to [7], wherein one component is removed in the state of the fabric and heat treatment is performed. A method for producing a fabric.

[10] The heat treatment according to the above [9],
A method for producing a fabric, wherein the method is carried out at 20 ° C. or higher, wherein the polyester fiber having the property (A) is changed to a polyester fiber having the following property (B).

Characteristics (B): (1) Crystallinity is 22 to 30% (2) Crystal size is 2.5 in terms of plane index (010)
nm to 4.5 nm, 2.5 n in plane index (100)
m to 4.5 nm, 2.0 n in plane index (-105)
m: 4.5 nm, and the difference in crystal size between the plane indices is 1.0 nm or less. (3) The degree of crystal orientation is 010 plane, 50 to 85%, -105.
(4) Amorphous degree is 0.15 to 0.40 (5) Amorphous density is 1.31 to 1.37 g / cm ³ (6) Amorphous density / amorphous degree is 3.2 or more (7) Apparent Young's modulus is 140 kgf / mm ² or less (8) Initial elongation is 8% or more

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in more detail.

The ultrafine polyester fiber obtained from the ultrafine fiber-generating conjugate fiber of the present invention has the following property (A). The characteristic (A) is as follows: (1) Specific gravity is 1.335 to 1.360 (g / cm ³ ) (2) Crystallinity is 21 to 26% (3) Crystal size is 1.4 in plane index (010)
To 2.2 nm, and 1.4 to 2.2 in plane index (100).
5 nm, 1.6-3.5 nm in plane index (described as -105 after 1 bar 05) (4) Crystal orientation degree is 75% or less on 010 plane, 85% or less on -105 plane, and (5) amorphous The degree of orientation is 0.15 to 0.4 and the shrinkage ratio of hot water is 0.
３５35%, and the dry heat shrinkage is 0-35%.

The ultrafine polyester fiber having the above-mentioned property A has an amorphous orientation degree of 0.15 to 0.3, a hot water shrinkage of 0 to 10%, and a dry heat shrinkage of 0 to 10%. %.

By subjecting the polyester fiber having the above characteristic value (A) and its fabric to high-temperature heat treatment, it can be transformed into a highly elastic polyester having the following characteristic value (B).

In the present invention, the ultrafine fiber-generating conjugate fiber for obtaining an ultrafine polyester fiber is an elution that elutes at least one component in conjugate fibers of sea-island type, chrysanthemum type, multi-layer composite type, blend spinning type, split type and the like. A mold or a split type in which a composite fiber composed of two or more components is divided into ultrafine fibers can be applied. Among them, it is preferable to use a polymer-inter-array fiber having a sea-island structure.

The sea component of the polymer-inter-array fibers having a sea-island structure according to the present invention is preferably made of a polyester obtained by copolymerizing sulfoisophthalic acid having high alkali solubility, for example, sodium sulfoisophthalate. What consists of polyester which acid-copolymerized is preferable. As the polyester of the island component, polyethylene terephthalate and a copolymer mainly containing it are used.

The ultrafine fiber-generating composite fiber for obtaining the above-mentioned ultrafine polyester fiber has a take-up speed of 2000 to 4000 m.
/ Min, preferably 2500-3500 m / min, which is obtained by subjecting the ultrafine fiber-generating conjugate fiber to a fabric such as a woven or knitted fabric and then subjecting it to a heat shrink treatment. .

The highly oriented unstretched fiber of the ultrafine fiber generating conjugate fiber is heated at a heater temperature of 250 ° C. without stretching.
It is preferable that the temperature be within a non-contact type heater of 300 ° C. or higher.
Under a tension of 3 × 10 ^-2 g / d to 5.0 × 10 ^-2 g / d,
It is obtained by passing through a processing speed of 300 m / min or more, preferably 400 m / min, and contracting 5 to 40%, preferably 10 to 35%.

Here, the tension is a value measured at a position immediately after leaving the heater. For those having a plurality of heater zones, it is the yarn tension at a position immediately after exiting the first heater. The heater temperature is 1c from the yarn path where the yarn runs.
This is the ambient temperature measured by the temperature sensor attached at a position within m within a state where the yarn is not running.
The processing speed is the yarn speed in the driving device after the final heat treatment.

In the present invention, the above-mentioned ultrafine fiber-generating composite fiber, for example, a polymer mutual array fiber, and another polyester-based ultrafine fiber-generating composite fiber, for example, a polymer mutual array fiber, are twisted or fluid-mixed. The fibers are mixed by a confounding process to form a mixed fiber.

Alternatively, an ultrafine fiber-generating conjugate fiber for obtaining an ultrafine polyester fiber and a polyester fiber having a single fiber fineness of 1 to 40 denier are mixed by twisting or fluid entanglement to form a mixed fiber.

The other polyester-based polymer array fibers use a polyester-based polymer in the island component and a polyester polymer in the sea component with higher alkali solubility.

As the polyester polymer of the island component,
Polyethylene terephthalate (PET), polypropylene terephthalate (PPT), polybutylene terephthalate (PBT), polylactic acid, or the like can be used.

The sea component is preferably a polyester made of a copolymer of sulfoisophthalic acid having a higher alkali solubility than the island component. For example, a polyester made of a copolymer of sodium sulfoisophthalic acid is preferable. Can be used.

In the present invention, the ultrafine polyester fiber having the above-mentioned property (A) is obtained by removing a sea component from a fabric using at least the above-described mixed yarn and further subjecting the fabric to heat treatment. It shrinks, leaving a distance between the other ultrafine polyester fibers and filling the gaps between the fibers. This fabric structure has extremely good flexibility, and can be made to exhibit excellent water repellency by performing a water repellent treatment.

When the heat treatment of the ultrafine polyester fiber having the above-mentioned property (A) is viewed in detail in time, the heat treatment may show the highest shrinkage during the heat treatment and then spontaneously elongate. However, the heat treatment eventually shows a shrinkage behavior as a whole. Therefore, heat treatment is performed in two or more stages, and heat treatment showing the highest shrinkage is performed in one stage.
If heat treatment is performed in the second stage after the first stage, spontaneous elongation occurs.

Such a shrinkage and spontaneous elongation behavior is an extra-fine polyester fiber having the above-mentioned property (A), and the distance between the extra-fine polyester fiber and the other extra-fine polyester fiber is further increased.
The space between the fibers is more completely filled, and the performance can be enhanced.

Further, the ultrafine polyester fiber having the property (A) may change its structure by the above-mentioned heat treatment, and may be transformed into a highly elastic polyester fiber having the property value (B). The elasticity-rich polyester fiber having such a characteristic value (B) will be described in detail later, but has rubber-like elasticity not seen in conventional polyester fibers, and is a thin, light, soft woven or knitted fabric. A fabric having excellent resilience, repetitive compression recovery, and shape retention can be obtained.

That is, the intermediate polyester fiber (A)
Although it does not have rubber-like elasticity by itself, it is converted into a fiber having a structure having the characteristic value (B) by heat-treating it at a high temperature, and exhibits rubber-like elasticity.

The heat treatment temperature of the fabric is preferably 120 ° C. or more, more preferably 140 ° C. or more, and particularly preferably 160 ° C. or more, with dry heat and / or wet heat.

By the above-mentioned heat treatment, the polyester fiber can be converted into a polyester fiber having a characteristic value (B) and a high elasticity.
This means that (1) the degree of crystallinity is 22-30%, preferably 24
~ 28% and the same level as conventional polyester drawn yarn,
(2) Isotropic crystal size, ie, plane index 010;
5 to 4.5 nm, 2.5 to 4.5 nm with a surface index of 100,
The plane index is −105 to 2.0-4.5 nm, and the difference in crystal size between the plane indices is 1.0 nm or less, preferably 0.7 nm or less. 0.15 to 0.40, preferably 0.20 to 0.32, and (4) high amorphous density, that is, 1.31 to 1.37.
g / cm ³ , preferably 1.34 to 1.37 g / cm ³
(5) Particularly, the value of amorphous density / amorphous orientation degree is extremely high, and the value is 3.2 or more, preferably 4.0 or more.

As the characteristics of the fiber, the initial elongation is as large as 8% or more, preferably 12% or more, the initial stress is as low as 1.5 g / d or less, and the apparent Young rates are less preferably 140 kgf / mm ² has a 100 kgf / mm ² or less and a low value.

The initial stress, initial elongation, and apparent Young's modulus are values measured by the following methods.

NS is the hot water shrinkage, KS is the dry heat shrinkage, and the measuring method is as follows. Tensile test: According to JIS-L1013. Initial stress, initial elongation; As shown in FIG. 1, the intersection of the first tangent and the second tangent in the SS curve obtained in the tensile test was defined as the initial stress and initial elongation. Apparent Young's modulus, hot water shrinkage, dry heat shrinkage; JIS-L1
013.

As the yarn form, a flat yarn is preferable, and the object of the present invention can be achieved, but it is also possible to use it as an air entangled yarn or a false twisted yarn.

The ultrafine polyester fiber used in the present invention has a single fiber fineness of 0.2 denier to 0.00001.
Preferably, it is denier.

The fabric used in the present invention can be applied to conventionally known fiber sheets such as woven fabric, knitted fabric and non-woven fabric, and is not particularly limited.

In the present invention, the cloth may be provided with a water-repellent agent such as a fluorine-based agent or an oil-repellent agent.

The fabric of the present invention can be used for general clothing materials and for sports such as skiing and skating, waterproof clothing such as raincoats, windbreakers and waterproof pants, and various water-repellent products.

The methods and conditions for measuring various characteristics used in the present invention are as follows. (1) Specific gravity: According to JIS-L1013 7.14.2 density gradient tube method. (2) Crystallinity; W.ruland method (W. Ruland, Acta Crys
t. , 14 (1961), 1180-1185) by the following wide-angle X-ray diffraction (diffractometer method).

X-ray generator: X-ray source manufactured by Rigaku Denki Co., Ltd .: CuKα ray (using Ni filter) Curved crystal monochromator (use of graphite) Output: 50 KV 200 mA Goniometer; slit diameter manufactured by Rigaku Denki Co., Ltd. 1 ° -0.15mm-1 ° Detector: Scintillation counter Counting and recording device; RAD-B scan system manufactured by Rigaku Corporation; 2θ / θ: continuous scan Measurement range: 2θ = 5 to 140 ° Sampling: 0. 02 ° Scan speed: 3 ° / min (3) Crystal size measurement by wide-angle X-ray diffraction; (a) Wide-angle X-ray diffraction (counter method) X-ray generator; X-ray source manufactured by Rigaku Corporation: CuKα Wire (using Ni filter) Output: 35 KV 15 mA Goniometer; manufactured by Rigaku Corporation Slit diameter: 2 mm pinhole collimator Detector: scintillation Unter counting recorder; RAD-C, online data processing system Equatorial scan range: 10 to 35 ° Meridian scan range: 30 to 55 ° Scanning method Step: 2θ / θ Sampling interval: 0.05 ° / Step integration Time: 2 seconds Circumferential (β) scan range: 90 to 270 ° Sampling interval: 0.5 ° / Step Integration time: 2 seconds (b) Wide-angle plate photography X-ray generator; manufactured by Rigaku Corporation : 4036A2 type X-ray source: CuKα ray (using Ni filter) Output: 35KV 15mA Slit diameter: 1mm diameter using pinhole collimator Shooting condition Camera radius: 40mm Exposure time: 20 minutes Film: Kodak DEF-5 Crystal size is calculated by surface index From the half widths of the peaks of (010), (100) and (−105), the following Sc herr
It was calculated using the equation of er.

L (hkl) = Kλ / β0 cosθB where L (hkl): average size in the direction perpendicular to the (hkl) plane of the microcrystal K: 1.0, λ: wavelength of X-ray, β0 = (ΒE2-βI
2) 1/2, βE: apparent half width (measured value) βI: 1.05 × 10 −2 rad. , ΘB: Bragg angle (4) Degree of crystal orientation by wide-angle X-ray diffraction measurement Calculated by the following formula from half width H of intensity distribution obtained by scanning each peak in the circumferential direction.

Crystal orientation degree (%) = [(180−H) / 1
80] × 100 (5) Degree of amorphous orientation by polarized fluorescence method Apparatus: FOM-1 manufactured by JASCO Optical system: Transmission method (excitation light wavelength: 365 nm, fluorescence wavelength:
(420 nm) Measurement system: Rotation was performed using a polarizer 偏光 analyzer and a polarizer〓analyzer to obtain an angular distribution of in-plane polarized fluorescence intensity (I‖, I〓).

Here, ‖ indicates parallel, and 〓 indicates vertical.

The degree of amorphous orientation is expressed by the following equation:
Asked in ² .

F ² = 3/2 [{I‖ (0) + 2I〓 (0)} / K- ／] where K = {I‖ (0) + 4I〓 (0) + 8 / 3I‖ (90 )｝ I‖ (0): ‖Relative polarization fluorescence intensity in the axial direction in measurement I (90): ‖Relative polarization fluorescence intensity in the orthogonal direction to the above in measurement I〓 (0): 〓Axial direction in measurement (6) Amorphous density Amorphous density (da) was determined by the following equation.

Da (g / cm ³ ) = [d-dc × [(Xc / 100) / dc] × d]
/ 1-[(Xc / 100) / dc] × d] d: fiber density (g / cm ³ ) dc: 1.501 Xc: crystallinity (%) The fiber density is JIS-L1013 7.14. The measurement was performed according to the two-density gradient tube method.

[0051]

EXAMPLES Example 1 and Comparative Example 1 A polyester system using polyethylene terephthalate as an island component and a copolyester polymer composed of a copolymer of terephthalic acid and 5% sodium sulfoisophthalic acid at 5 mol% as a sea component. A sea-island type polymer mutual array having an island / sea ratio of 80/20 was spun at 3500 m
The spinning was carried out at a speed of / min to produce a POY having a total denier of 96D x 24 filaments.

On the other hand, the same polyester-based islands-in-sea polymer array as above was spun at a spinning speed of 1500 m / min, and then hot-drawn at a draw ratio of 3 times to obtain a total denier of sea-island-type polymer inter-array fibers. A polyester drawn yarn of 75D × 24 filament was used.

After the two yarns are combined and subjected to air entanglement treatment and mixed, the mixed yarn is used as a warp yarn and a weft yarn of a plain fabric to form a high-density fabric, and the fabric is boiled. The fabric was heat shrunk in water for 5 minutes to obtain a fabric A-1. This fabric A-
Part 1 was taken out, immersed in an aqueous solution of caustic soda to dissolve and remove the sea component, and the characteristics of the ultrafine fibers, which were island components obtained from POY, were examined.

1. Specific gravity: 1.34 (g / cm ³ ) 2. Crystallinity: 22% 3. 3. Crystal size 1.7 nm in plane index (010) 1.6 nm in plane index (100) 2.5 nm in plane index (-105) 4. Crystal orientation 53% on 010 plane -72% on 105 plane 5. Amorphous orientation degree: 0.22 The hot water shrinkage was 4%, and the dry heat shrinkage was 3%. Next, the fabric was heat-treated at 180 ° C for 5 minutes for dryness to serve as a fabric A-2. The high-density woven fabric was heat-treated at 180 ° C. for 5 minutes at a stretch without boiling water treatment to obtain a woven fabric B.

The woven fabric A-2 and the woven fabric B were each immersed in an aqueous solution of caustic soda to dissolve and remove the sea component (although the island component was also slightly removed).

For the fabric A-2 and the fabric B, the PO
When the characteristics of the ultrafine fibers, which are the island components obtained from Y, were examined, the following characteristics were exhibited.

Fabric A-2 Fabric B 1. Crystallinity (%) 24 22 2. Crystal size (nm) Plane index (010) 3.1 3.2 Plane index (100) 3.5 3.5 Plane index (-105) 3.3 3.3 Crystal size difference between plane indexes 0.4 0.3 3. Crystal orientation degree (%) Plane index (010) 75 72 Plane index (-105) 68 68 4. Amorphous orientation degree 0.28 0.27 5. Amorphous density (g / cm ³ ) 1.35 1.35 6. Amorphous density / amorphous orientation degree 4.8 5.0 7. 7. Apparent Young's modulus (kgf / mm ² ) 76 81 Initial elongation (%) 18 16 On the other hand, as Comparative Example 1, two drawn polyester yarns of the sea-island type polymer mutual array fiber total denier 75D × 24 filament of Example 1 were twined and air-entangled. After blending, this blended yarn was used as the warp yarn and weft yarn of the plain fabric to form a high-density fabric C, and this fabric C was immersed in an aqueous solution of caustic soda to dissolve and remove the sea component (the island component was also removed). Although it is slightly removed).

When the woven fabrics A, B and C from which these sea components had been removed were seen through a fluorescent lamp, the degree of denseness was as follows. Was scattered from between the fabric structures, and the woven fabrics A and B of Example 1 were very little scattered from between the fabric structures.

The woven fabrics A, B and C of Example 1 were further subjected to pressure dyeing at 125 to 130 ° C. using a disperse dye, and thereafter Asahigard AG-710 (Asahi Glass Co., Ltd.)
Woven fabrics A and B
Is remarkably extremely flexible as compared with the woven fabric C, is excellent in resilience and shape retention, shows excellent water repellency in which a polka dot runs extremely fast in a water repellency test, and has a water pressure of 500 mmHg.
And good water resistance exceeding. Example 2 Polyester-based sea-island type polymer mutual array using polyethylene terephthalate as an island component, and a copolymerized polyester polymer comprising 5 mol% of a copolymer of terephthalic acid and pentasodium sulfoisophthalic acid as a sea component, Spinning speed of 3500m with an island / sea ratio of 80/20
The spinning was carried out at a speed of / min to produce a POY having a total denier of 96D x 24 filaments.

Without stretching this raw yarn, the inside of a two-stage non-contact heater (each 1 m in length) in a 400 ° C. atmosphere is
The treated yarn was shrunk by about 20% at a flow rate of 00 m / min.

A portion of this yarn was immersed in an aqueous solution of caustic soda to dissolve and remove the sea component. The properties of the ultrafine fibers showed the following values.

1. Specific gravity: 1.35 (g / cm ³ ) 2. Crystallinity: 23% 3. 3. Crystal size 1.9 nm in plane index (010) 1.7 nm in plane index (100) 2.9 nm in plane index (−105) 4. Crystal orientation degree 51% on 010 plane-78% on 105 plane 5. Amorphous orientation degree: 0.20 The shrinkage-treated yarn of sea-island type polymer mutual array fiber having a hot water shrinkage of 3% and a dry heat shrinkage of 2%
Air entangled processing is performed on the drawn yarn D of 36 denier filaments, and this is used for warp and weft to fabricate a plain woven fabric.
Heat treatment was performed in a hot air dryer at 0 ° C. for 3 minutes.

Next, the woven fabric C was immersed in an aqueous solution of caustic soda to dissolve and remove sea components.

When the properties of the ultrafine fiber and the drawn yarn D obtained by this treatment were examined, the following properties were shown.

Ultrafine Fiber Draw Yarn D 1. Crystallinity (%) 24 28 2. Crystal size (nm) Plane index (010) 3.5 3.8 Plane index (100) 3.4 3.4 Plane index (-105) 2.8 4.5 3.5. Crystal orientation (%) Plane index (010) 63 88 Plane index (-105) 41 88 4. Amorphous orientation degree 0.27 0.52 5. Amorphous density (g / cm ³ ) 1.35 1.31 6. Amorphous density / amorphous orientation degree 5.0 2.5 7. 7. Apparent Young's modulus (kgf / mm ² ) 72 450 Initial elongation (%) 146 Next, dyeing was performed using a disperse dye at 130 ° C for 20 minutes. The obtained woven fabric had good resilience, and had a performance of returning to the original sheet shape with a feeling of pan when held and released.

When this fabric was subjected to a water-repellent treatment using Asahi Guard AG-710 (manufactured by Asahi Glass Co., Ltd.), it showed excellent water repellency in which polka dots run extremely fast as in Example 1. In addition, good water resistance exceeding a water resistance pressure of 500 mmHg was exhibited.

[0067]

According to the present invention, a fabric such as a high-density woven or knitted fabric which is excellent in resilience and shape retention while being a thin, light and soft woven or knitted fabric using ultra-fine polyester fiber is obtained. I was able to.

[Brief description of the drawings]

FIG. 1 is an SS curve illustrating the initial stress and the initial elongation of the polyester fiber of the present invention.

 ──────────────────────────────────────────────────続 き Continued on the front page F-term (reference) 4L036 MA05 MA16 MA24 MA26 MA33 PA01 PA03 PA33 PA41 UA07 4L041 AA08 AA20 BA04 BA05 BA16 BC01 BC05 BC17 BC20 BD14 CA06 CA11 DD01 DD11 DD14 EE06 EE09 EE15 EE20 4L048 AA20 AA21A AA51 AB08 AB09 AC12 AC19 BA01 BA02 CA00 CA04 CA08 CA12 EB04 EB05

Claims (10)

[Claims] An ultrafine polyester fiber obtained from an ultrafine fiber-generating conjugate fiber having the following property (A). Characteristics (A) (1) Specific gravity is 1.335 to 1.360 (g / cm ³ ) (2) Crystallinity is 21 to 26% (3) Crystal size is 1.4 in plane index (010)
To 2.2 nm, and 1.4 to 2.2 in plane index (100).
5 nm, 1.6-3.5 nm in plane index (described as -105 after 1 bar 05) (4) Crystal orientation degree is 75% or less on 010 plane, 85% or less on -105 plane, and (5) amorphous The degree of orientation is 0.15 to 0.4 and the shrinkage ratio of hot water is 0.
~ 35%, and the dry heat shrinkage is 0 ~ 35% 2. An ultrafine polyester fiber having the property A,
Amorphous degree 0.15-0.3, hot water shrinkage 0-10
% And a dry heat shrinkage of 0 to 10%. 3. A polyester mixed yarn, wherein the ultrafine polyester fiber according to claim 1 or 2 and another ultrafine polyester fiber are mixed. 4. A polyester mixed yarn comprising a mixture of the ultrafine polyester fiber according to claim 1 and a polyester fiber having a single fiber fineness of 1 to 40 denier. 5. The polyester blended yarn according to claim 1, wherein the ultrafine polyester fiber is obtained by removing one component from a sea-island type conjugate fiber. 6. The polyester mixed yarn according to claim 3, wherein the mixed fiber is formed by air entanglement. 7. The mixed fiber according to claim 3, wherein the other ultrafine polyester fibers are ultrafine polyester fibers obtained by removing one component from ultrafine fiber-generating conjugate fibers. 8. A fabric comprising at least the ultrafine polyester fiber or the polyester mixed fiber according to any one of claims 1 to 7. 9. A fabric using at least one of the ultrafine fiber-generating conjugate fibers according to any one of claims 1 to 7, wherein one component is removed in a state of the fabric and heat treatment is performed. Production method. 10. A method for producing a fabric, wherein the heat treatment according to claim 9 is carried out at a temperature of 120 ° C. or higher to convert the polyester fiber having the property (A) into a polyester fiber having the following property (B). Properties (B): (1) Crystallinity is 22 to 30% (2) Crystal size is 2.5 in plane index (010)
nm to 4.5 nm, 2.5 n in plane index (100)
m to 4.5 nm, 2.0 n in plane index (-105)
m: 4.5 nm, and the difference in crystal size between the plane indices is 1.0 nm or less. (3) The degree of crystal orientation is 010 plane, 50 to 85%, -105.
(4) Amorphous degree is 0.15 to 0.40 (5) Amorphous density is 1.31 to 1.37 g / cm ³ (6) Amorphous density / amorphous degree is 3.2 or more (7) Apparent Young's modulus is 140 kgf / mm ² or less (8) Initial elongation is 8% or more