JP2000110025A - Polyester fiber - Google Patents

Abstract

PROBLEM TO BE SOLVED: To simply obtain a polyester fiber capable of providing a spontaneously elongating fiber having excellent qualities in excellent operability and productivity and producing a woven and a knitted fabrics having improved hand by making the fiber show an X letter pattern by small-angle X-ray scattering and have a specific elongation and specified Uster irregularity. SOLUTION: This polyester fiber simultaneously shows (i) an X letter pattern by small-angle X-ray scattering and has (ii) >=80% elongation and (iii) <=2% Uster unevenness. Preferably the polyester fiber has >=1.5 nm crystal size in the direction of (100) plane. Preferably the fiber is heat-treated under relaxation to give a polyester fiber, which is mixed with a highly shrinkable fiber having >=10% shrinkage percentage in boiling water to give a polyester combined filament yarn and the combined filament yarn is used to produce a woven and a knitted fabrics.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polyester fiber which is excellent in swelling, softness and resilience and can provide a woven or knitted fabric having no stain.

[0002]

2. Description of the Related Art Polyester has various excellent properties including mechanical properties, and is therefore used in various fields including clothing. In clothing applications, quality has been improved targeting natural fibers, but especially as a means to realize a swelling and soft texture.
A so-called shrinkage difference mixed yarn which mixes fibers having different shrinkage characteristics due to heat is widely used. Recently, shrinkage-differential mixed yarns using so-called spontaneously elongated yarns exhibiting extensibility by heat have attracted attention. If this type of shrinkage difference mixed yarn is used, a sufficient difference in yarn length can be obtained after the dyeing process even if the density of the woven fabric increases, and a fabric excellent in swelling and softness can be obtained.

Conventionally, as a method for producing a spontaneously elongated yarn, for example, Japanese Patent Application Laid-Open No. 2-93410 discloses a method in which a highly oriented undrawn yarn (hereinafter abbreviated as POY) is subjected to a relaxation heat treatment as it is. The supply yarn POY at this time is generally 30
It was a substantially amorphous fiber spun at about 00 m / min. However, in the conventional method of producing spontaneously elongated yarn, a high-temperature treatment of about 200 ° C. is often used in the relaxation heat treatment step.If the supply yarn is amorphous, melt cutting frequently occurs and productivity decreases. In addition, there is a problem that the fibers are fused and the quality is deteriorated. Furthermore, since the POY to be supplied is an amorphous fiber, there has been a problem of process instability and yarn spots due to fluctuations in processing tension due to aging.

For the purpose of improving yarn spots, Japanese Patent Application Laid-Open No. 9-324321 proposes a POY having a small thread spot as a supply yarn for spontaneously growing yarns. However, since this POY is produced at a spinning speed of 2900 to 3200 m / min, it is substantially amorphous like the conventionally supplied yarn, and the above-mentioned problem cannot be solved.

On the other hand, Japanese Patent Application Laid-Open No. 62-206015 discloses high-speed spinning at a spinning speed of 5,000 m / min or higher, or highly oriented crystallized fiber using a high-viscosity polyester, followed by relaxation heat treatment, followed by relaxation heat treatment. A method for obtaining shaped fibers is disclosed. However, as shown in the examples of the publication, the dry heat shrinkage of the supply yarn is about 5% and the oriented crystallization is highly advanced, so that it is difficult to obtain a spontaneously stretched yarn even when subjected to a stretching relaxation heat treatment. It is.

[0006]

DISCLOSURE OF THE INVENTION The present invention solves various problems caused by the fact that the fibers supplied to the processing in the production of spontaneously elongated yarns are amorphous, and are more productive and simple. Moreover, the present invention provides a polyester fiber which is a supply yarn for obtaining a spontaneously elongated yarn having excellent quality such as dye spots.

[0007]

The above object is achieved by a polyester fiber having the following properties. (1) Shows an X-shaped pattern by small angle X-ray scattering (2) Elongation ≧ 80% (3) Worcester spot ≦ 2%

[0008]

DETAILED DESCRIPTION OF THE INVENTION In the present invention, in producing spontaneously elongated yarn, various problems caused by the relaxation heat treatment of the conventional amorphous highly oriented undrawn yarn are obtained by using crystallized POY as a supply yarn. It is an object of the present invention to provide a spontaneously-extended yarn of excellent quality easily with good operability and productivity, and to provide a high-quality woven or knitted fabric with excellent texture.

The polyester in the present invention refers to a polymer having an ester bond, and polyethylene terephthalate (hereinafter abbreviated as PET) is the most general and preferred. In addition, some of the diol component and the acid component
It may be substituted with another copolymerizable component in the range of 15 mol% or less. They may also contain additives such as other polymers, matting agents, flame retardants, antistatic agents, pigments and the like. Hereinafter, a description will be given using PET as an example.

In the present invention, it is essential that the small-angle X-ray scattering pattern shows an X-shaped pattern. This X-shaped pattern (FIG. 2) is described in, for example, Jpn J. Soc., Vol. 38, P-514 (1982).
As described in Japanese Patent Application Laid-Open No. H11-260, an ordered structure in which crystals are regularly arranged has been proposed, which is peculiar to a high-speed spun fiber having high crystallinity (FIG. 3). FIG. 3 illustrates this ordered structure. In FIG. 3, rectangles indicate crystal regions, which indicate that they are regularly arranged in a checkered pattern. The amorphous region exists between the crystal regions.
That is, the X-shaped pattern indicates that crystallization has advanced to a high degree and an ordered structure has been formed. For this reason, fibers having an X-shaped pattern have good dimensional stability and heat resistance due to the progress of crystallization.

Further, the crystal size in the (100) plane direction is 1.
If it is 5 nm or more, it indicates that crystallization has sufficiently progressed, and it is preferable. It is more preferably at least 2.0 nm.
Since the polyester fiber of the present invention has an ordered structure in which crystallization has progressed in this manner, the polyester fiber has good heat resistance and little change over time.

Further, in order to suppress dimensional stability due to aging and to further stabilize the process, the so-called structural integrity parameter (ε0.2) is preferably 0.40 or less. As described in Japanese Patent Application Laid-Open No. 48-35112, the structural integrity parameter is treated with boiling water for 2 minutes under a load of 0.18 cN / dtex (0.2 gf / d). calculate. Structural integrity parameter (ε0.2) = [(L ₁ ′ −L ₀ ′)
_{/ L 0 ')] L 0} ': thread the shackles up initial load 0.18cN / dtex (0.2gf / d) original length of the skein was measured under L _1: 0.18cN the shackles of the measurement of the 'L _0' / Treated in boiling water for 2 minutes under dtex (0.2gf / d) load, and air-dried to an initial load of 0.
Shackle length under 18 cN / dtex (0.2 gf / d) As described above, the structural integrity parameter indicates the creep characteristics under wet heat. The smaller this value is, the more the crystallization proceeds and the more stable the dimensional stability is. It shows that it is good. The structural integrity parameter is more preferably 0.25 or less, even more preferably 0.15 or less. As described above, the productivity of the polyester fiber of the present invention is higher than that of amorphous POY, which is a conventional supply yarn, and the stability of the process and quality is dramatically improved.

Further, from the viewpoint of quality stability, it is better that the yarn spots are small, and the worst spots must be 2% or less. Preferably, Worcester spots are 1% or less.

By the way, the polyester fiber of the present invention needs to have a yarn elongation of 80% or more in view of the versatility of subsequent processing. It is preferably at least 100%.

Although relaxation heat treatment is suitable for the production of spontaneously elongated yarns, shrinking at as low a temperature as possible and shrinkage are important to stabilize the relaxation heat treatment step.
The peak temperature of the shrinkage stress is preferably 85 ° C. or lower, which makes it possible to lower the heater temperature at the time of the relaxation heat treatment, so that the fusion of the yarn hardly occurs and the energy cost can be reduced. The peak temperature of shrinkage stress is more preferably 80 ° C. or lower. Further, considering the stability of the relaxation heat treatment, the shrinkage ratio is preferably 10% or more in terms of boiling water shrinkage ratio. It is more preferably at least 15%.

The cross-sectional shape of the fiber obtained in the present invention is not particularly limited, and a round cross-section, a triangular or other irregular cross-section, a hollow cross-section, or the like can be employed. The single-fiber fineness is also not particularly limited, but considering the case where the single-fiber fineness is used for a sheath yarn of mixed fiber, the single-fiber fineness is preferably 0.3 to 5.0 dtex. More preferably 0.6-3.0
dtex.

Since the crystallization of the polyester fiber of the present invention has progressed, it is possible to use the polyester fiber as it is, or to use it after performing a constant-length heat treatment. It is preferably used as a spontaneously elongated yarn. Spontaneously elongated yarn has a dry heat shrinkage of 0%
The following shall be mentioned.

Further, it is preferable that the polyester fiber of the present invention is subjected to a relaxation heat treatment, then entangled and mixed with a polyester shrink yarn having a boiling water shrinkage of 10% or more, and used as a shrinkage difference mixed yarn. Boiling water shrinkage of polyester shrink yarn is 15%
Above is preferable because the swelling feeling is further excellent. If the boiling water shrinkage ≧ dry heat shrinkage in the polyester shrink yarn, the fabric is loosened during the dry heat setting of the woven fabric, and the yarn in the woven fabric is given a degree of freedom. The preferred fabric is obtained.

It is preferable to use a fiber having excellent stretchability, such as PBT, as the polyester shrinkable yarn, because it has a soft and resilient texture different from PET.

The polyester fiber of the present invention can be produced by a known spinning device, and is not limited to a production method. However, from the viewpoint of suppressing yarn spots, it is preferable to use a focused refueling guide and to set the focused refueling position to 1.3 to 3.0 m below the base. If the bundle refueling position is 1.3 m or less below the base, the bundles are sufficiently cooled before the bundle refueling, so that fusion between single yarns can be suppressed. In addition, yarn spinning is reduced due to an increase in spinning tension due to air resistance, and yarn spots can be suppressed. On the other hand, if the focused refueling position is 3.0 m or less, it is possible to prevent cold drawing due to excessive spin tension increase due to air resistance, and to suppress yarn spots. Furthermore, if the bundled lubrication position is too close to the spinneret, not only will the fusion between the single yarns occur, but also the yarn may be rapidly cooled by lubrication and prevent crystallization, so the yarn temperature may be reduced to 80 ° C or less. It is preferable to appropriately select the focusing refueling position so that refueling is performed when the temperature decreases.

In addition, from the viewpoint of promoting oriented crystallization only by spinning, it is preferable to perform high-speed spinning. However, as the spinning speed is increased, excessively oriented crystallization proceeds and the elongation and shrinkage of the fiber are excessively reduced.
00-4500 m / min is preferred. More preferably 3700-4300m /
Minutes. Even if the spinning is performed at the same spinning speed, the degree of oriented crystallization of the fiber varies depending on the polymer viscosity, single-filament fineness, cooling conditions, and the like. Therefore, it is preferable that the spinning speed be appropriately changed depending on the polymer viscosity and the spinning conditions.

The fiber obtained by the present invention is suitably used for clothing such as blouses, suits, pants and coats.

[0023]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to embodiments. In addition, the measuring method in the Example used the following method. A. Intrinsic viscosity [η] Measured in orthochlorophenol at 25 ° C.

B. Small-angle X-ray scattering A scattering pattern was taken under the following conditions. X-ray generator: RU-200 manufactured by Rigaku Corporation X-ray source: Cu-Kα ray (using Ni filter) Output: 50kV-150mA Slit system: 0.5mmφ Camera radius: 400mm Exposure time: 120 minutes Film: Kodak DEF-5

C. Crystal Size A wide-angle X-ray diffraction measurement was performed under the following conditions, and the crystal size was calculated from the half width of the (100) plane reflection using the Scherrer equation. X-ray diffractometer: 4036A2 type, manufactured by Rigaku Corporation X-ray source: Cu-Kα ray (using Ni filter) Output: 40kV-20mA Goniometer: Slit system: manufactured by Rigaku Corporation: 2mmφ-1 ° -1 ° Detector: Scintillation counter Count recorder: RAD-C type RAD-C equatorial scan: Step scan 2θ = 10 to 55 °, step = 0.05 °, integration time = 2 seconds Scherrer equation L = λ / Β ₀ cos θ _B L: crystal size [angstrom], λ: wavelength of X-ray (1.5418 angstrom) θ _B : Bragg angle, β ₀ : (β _E ² −β _I ² ) ^1/2 β _E : half width Measured value, β _I : Equipment constant (1.046 × 10 ^-2 )

D. Boiling water shrinkage and dry heat shrinkage Boiling water shrinkage (%) = [(L ₀ −L ₁ ) / L ₀ )] × 100
(%) Dry heat shrinkage (%) = [(L ₀ −L ₂ ) / L ₀ )] × 100 (%) L ₀ : The drawn yarn is shackled and the shackle is measured under an initial load of 0.09 cN / dtex. Original length L ₁ : The shackles measured for L ₀ were treated in boiling water for 15 minutes in a substantially load-free state, and after air-drying, shackles under an initial load of 0.09 cN / dtex L ₂ : Shackles for which L ₁ was measured Is treated with dry heat (160 ° C) for 15 minutes in a substantially load-free state, and after air drying, initial load is 0.09 cN / dt
shackle length under ex

E. Structural integrity parameter As described in JP-A-48-35112, 0.18 cN / dtex (0.2
gf / d) The treatment was carried out for 2 minutes in boiling water under a load, and calculated from the dimensional change of the yarn before and after the treatment by the following formula. Structural integrity parameter = [(L ₁ ′ −L ₀ ′) /
L ₀ ′)] L ₀ ′: The original length of the shackle measured under an initial load of 0.18 cN / dtex (0.2 gf / d) by staking the thread L ₁ ′: The shackle measured at L ₀ ′ is 0.18 cN / dtex (0.2gf / d) Treated in boiling water for 2 minutes under a load, air-dried to an initial load of 0.
Shackle length under 18cN / dtex (0.2gf / d)

F. Elongation A load-elongation curve was obtained according to JIS standard L1013, and the elongation was divided by the initial sample length to obtain the elongation.

G. Worcester spots Using Zellweger USTER TESTER 1 Model C, 2
The measurement was performed in the normal mode while supplying the yarn at a speed of 00 m / min.

H. Peak temperature of shrinkage stress Thermal stress measurement machine TYPE KE manufactured by Kanebo Engineering
The measurement was performed using -2S. Create a loop with a sample length of 10 cm x 2 and apply an initial tension (Dtexix x 0.9 x 1/30 x 0.98) cN
Was applied. The heating rate was set to 150 ° C./min, and a contraction stress curve against the temperature was drawn. The maximum value of the contraction stress and the temperature were read.

I. Dyed spots Fiber was knitted in a tube, dyed by a conventional method, and dyed spots were evaluated by sensory evaluation. At this time, scoring was performed with no dyeing spot as 0. A score of 15 or less was accepted.

EXAMPLE 1 285 of homo-PET without titanium oxide having an intrinsic viscosity of 0.63 was prepared.
C. and filtered using a stainless steel nonwoven fabric filter 2 having an absolute filtration diameter of 15μ, and then a pore diameter of 0.25 mm and a pore length of 0.4 m
The spinning temperature was 290 ° C. from a round hole die 3 having 24 m holes and 24 holes.
Then, after bundle lubrication was performed by the guide lubrication device 6 at 1.9 m below the spinneret, the yarn was taken out at a spinning speed of 3700, 4000, and 4300 m / min, and a fiber of 56 dtex and 24 filaments was wound up (FIG. 4). At this time, the peripheral speeds of the first roller 8 and the second roller 9 were the same, and this was used as the spinning speed.

Each of the wound yarns showed an X-shaped pattern by small-angle X-ray scattering as shown in FIG. Table 1 shows the physical property values. These supply yarns are subjected to a relaxation heat treatment at a relaxation rate of 15% using a non-contact heater between the first roller 13 and the second roller 15 using the apparatus shown in FIG. 7% and -3% spontaneously elongated yarns were obtained. Further, since the supply yarn had high heat resistance, there was no yarn breakage due to fusion or melt cutting during processing. further,
Since the change with time was small, the processing tension was small, the processing was stable, and the number of dye spots was 10 and the number of yarn spots was small. The temperature of the non-contact heater 14 (effective length 1000 mm)
Is 180 ° C and the relaxation rate (%) is [(1st roller 1
Peripheral speed of 3−peripheral speed of second roller 15) / first roller 1
3 peripheral speed] × 100 (%). The processing speed (second roller peripheral speed) was 650 m / min.

Comparative Example 1 Spinning was carried out under the same conditions as in Example 1 except that the spinning speed was 3000 m / min, and a fiber of 56 dtex and 24 filaments was wound up. The wound yarn showed only central scattering due to small-angle X-ray scattering, but no X-shaped pattern was observed, and was a substantially amorphous fiber. Therefore, when the relaxation heat treatment was performed in the same manner as in Example 1, yarn breakage due to fusion or melt cutting frequently occurred.

Comparative Example 2 Spinning was carried out under the same conditions as in Example 1 except that the spinning speed was set at 5000 m / min, and a fiber of 56 dtex and 24 filaments was wound up. The wound yarn had a low elongation of 70%, and excessively crystallized, and had a low boiling water shrinkage of 6%. When this fiber was used as a supply yarn and subjected to relaxation heat treatment in the same manner as in Example 1,
Due to the low boiling water shrinkage, the relaxation heat treatment became unstable, and yarn breakage frequently occurred. Furthermore, the heat-treated relaxed yarn has a dry heat shrinkage of 1.
It showed no spontaneous elongation of 2%.

Comparative Example 3 Spinning was performed at a spinning speed of 4000 m / min under the same conditions as in Example 1 except that the guide lubrication position was set at 3.3 m below the base.
The filament fibers were wound up. Worcester spots on the wound yarn were as high as 2.5%. Using this fiber as a supply yarn, a relaxation heat treatment was carried out in the same manner as in Example 1, and a fabric was formed and dyed. As a result, 70 spots of dyeing and spots of dyeing occurred frequently.

Comparative Example 4 Spinning was performed at a spinning speed of 4000 m / min under the same conditions as in Example 1 except that the guide lubricating position was set at 1.0 m below the base.
The filament fibers were wound up. Worcester spots on the wound yarn were as high as 2.2%, and small angle X-ray scattering showed only central scattering but no X-shaped pattern. When this fiber was used as a supply yarn and subjected to relaxation heat treatment in the same manner as in Example 1, frequent fusion and fusion cutting occurred. In addition, when a fabric was formed using the relaxed heat-treated yarn and then dyed, 60 spots of dyed spots and spotted spots occurred frequently.

Example 2 Spinning was performed at a spinning speed of 3500 m / min under the same conditions as in Example 1 except that the fiber was 56 dtex, 144 filaments, and the guide lubrication position was 1.5 m below the die. The wound yarn showed an X-shaped pattern by small angle X-ray scattering as shown in FIG. In addition, the physical properties are shown in Table 1. As a result, a fiber suitable as a supply yarn of spontaneously elongated yarn having small plaques due to crystallization was obtained. This supply yarn,
After stretching 1.1 times with the device of Fig. 5, the relaxation rate is 20%
As a result, a high-quality spontaneously elongated yarn having a dry heat shrinkage of -7% was obtained. In addition, since the heat resistance of the supply yarn was high, there was no yarn breakage due to fusion or melting during processing. Furthermore, since the change with time was small, the processing tension fluctuation was small and the processing was stable, and 10 spots of dyeing and yarn spots were small.

Example 3 The spinning speed was the same as in Example 1 except that the fiber was 56 dtex, 12 filaments, and the guide lubricator was 2.7 m below the base.
Spinning was performed at 4500 m / min. The winding yarn is a small angle X as shown in FIG.
An X-shaped pattern was shown by line scattering. In addition, the physical property values are shown in Table 1. As a result, crystallization progressed, and fibers suitable as a supply yarn of spontaneously elongated yarn with small spots were obtained. By subjecting these supplied yarns to a relaxation heat treatment at a relaxation rate of 10% in the same manner as in Example 1, a high-quality spontaneously elongated yarn having a dry heat shrinkage of -2% was obtained. In addition, since the heat resistance of the supply yarn was high, there was no yarn breakage due to fusion or melting during processing. Furthermore, since the change with time was small, the processing tension was small, the processing was stable, and five spots of dyeing and spots of thread were small.

Example 4 Spinning was performed at a spinning speed of 3400 m / min under the same conditions as in Example 1 except that the intrinsic viscosity of the homo PET was 0.75. The wound yarn showed an X-shaped pattern by small angle X-ray scattering as shown in FIG.
In addition, the physical properties are shown in Table 1. As a result, a fiber suitable as a supply yarn of spontaneously elongated yarn having small plaques due to crystallization was obtained.
These yarns were supplied with a relaxation rate of 15% in the same manner as in Example 1.
As a result, a high-quality spontaneously elongated yarn having a dry heat shrinkage of -3% was obtained. Further, since the supply yarn had high heat resistance, there was no yarn breakage due to fusion or melt cutting during processing. Furthermore, since the change with time was small, the processing tension fluctuation was small and the processing was stable, and 10 spots of dyeing spots and thread spots were also small.

[0041]

[Table 1] Example 5 Spontaneous elongation yarn using spun yarn having 33 dtex, 24 filaments, shrinkage ratio of boiling water of 21.2%, dry heat shrinkage ratio of 19.4% and fiber spun at 4000 m / min in Example 1 (spontaneous elongation ratio: 7%) The fibers were mixed with each other while air-entangled by interlacing to obtain a 99dtex, 48-filament differential shrinkage mixed yarn. 300 turns / m of S
Twist was performed, and plain weave was woven using the warp and the weft. This was subjected to a 10% alkali weight reduction by a conventional method, followed by dyeing and dry heat setting. In the obtained fabric, the spontaneously elongated yarn emerges on the surface of the fabric, and has a soft and bulging feeling.
Furthermore, it was also excellent in resilience. Also, staining spots,
It was a high quality fabric with almost no wrinkles.

[0042]

EFFECT OF THE INVENTION By adopting the polyester fiber of the present invention, various problems caused by the relaxation heat treatment of the amorphous highly oriented undrawn yarn can be solved. It can be obtained with high productivity, and can provide a high quality woven or knitted fabric excellent in texture.

[Brief description of the drawings]

FIG. 1 is a diagram showing a small-angle X-ray scattering pattern of the present invention.

FIG. 2 is a diagram showing a small-angle X-ray scattering pattern of a high-speed spun fiber.

FIG. 3 is a diagram showing an ordered structure of a high-speed spun fiber.

FIG. 4 is a diagram illustrating a spinning device.

FIG. 5 is a diagram illustrating a relaxation heat treatment apparatus.

[Explanation of symbols]

1: spin block 11: supply yarn 2: non-woven fabric filter 12: feed roller 3: base 13: first roller 4: chimney 14: non-contact heater 5: yarn 15: second roller 6: lubrication guide 17: processed yarn 7 : Interlace nozzle 8: First roller 9: Second roller 10: Winding yarn

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 4L035 AA08 BB32 BB33 EE08 EE20 HH10 4L036 MA05 MA25 MA33 MA39 PA10 PA33 RA03 UA01 UA30 4L048 AA20 AA21 AA42 AB09 BA02 CA04 CA13

Claims (5)

[Claims] 1. A polyester fiber having the following properties. (1) Shows an X-shaped pattern by small angle X-ray scattering (2) Elongation ≧ 80% (3) Worcester spot ≦ 2% 2. The polyester fiber according to claim 1, wherein the crystal size in the (100) plane direction is 1.5 nm or more. 3. A polyester fiber obtained by subjecting the polyester fiber according to claim 1 or 2 to a relaxation heat treatment. 4. A polyester blended yarn obtained by blending the relaxed heat-treated polyester fiber according to claim 3 with a high shrinkage yarn having a boiling point of 10% or more. 5. A woven or knitted fabric using the polyester mixed fiber yarn according to claim 4.