JPH1088423A - Antistatic polyester fiber - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain antistatic polyester fibers excellent in antistatic performance. SOLUTION: The antistatic polyester fibers are obtained by melt spinning a polyester, consisting essentially of ethylene terephthalate and containing 0.5-5wt.% polyalkylene glycol and 0.1-2wt.% metallic organic sulfonate as antistatic agents added thereto under conditions satisfying requirements of (A) >=3msec time required for the polymer to pass through a unit volume V1 indicated by the product of the opening area S1 of a signal hole of a spinneret and the length L2 of the signal hole part, (B) <=800cm/min discharging linear velocity V0 of the polymer through the signal hole of the spinneret and (C) <=200 ratio (Vsp /V0 ) of the winding speed (Vsp ) of the discharged filaments to the discharging linear velocity (V0 ) of the polymer through the single hole of the spinneret. Thereby, may independent phases of the polyalkylene glycol oriented in the fiber axial direction at <50% ratio of the discontinuous phase to the total number of the independent phases at <=0.1μm average interphase interval in the fiber are formed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an antistatic polyester fiber from a polyester to which a polyalkylene glycol and a metal salt of an organic sulfonic acid are added.

[0002]

2. Description of the Related Art Polyester fibers are widely used not only for clothing but also for industrial materials because of their excellent properties, but have the drawback that they have high electric resistance and are easily charged with static electricity. Therefore, various methods have been proposed in order to improve the disadvantage of being easily charged with static electricity.
One of the methods is to knead an antistatic agent into polyester. For example, JP-B-46-22200 and JP-B-47
Japanese Patent Application Laid-Open No. Sho 5-10246 and Japanese Patent Publication No. 47-11280 discloses a method in which polyoxyalkylene glycol and sodium alkylbenzene sulfonate are mixed as an antistatic agent.
Japanese Patent Application Publication No. 3-149247 proposes that a polyoxyalkylene glycol and sodium alkyl sulfonate are mixed as an antistatic agent, and Japanese Patent Publication No. 57-4724 discloses that an antistatic polymer is streaked in the fiber axis direction. It has also been proposed to disperse in a shape.

However, in the conventional method, a satisfactory antistatic performance cannot be obtained with a small amount of an antistatic agent.
Further, when the compounding amount of the antistatic agent such as polyoxyalkylene glycol is increased for the purpose of improving the antistatic performance, the yarn-forming stability, heat resistance, and the like are reduced, and there is a disadvantage that stain spots and the like are easily generated. In the conventional method, one of the reasons why a small amount of the antistatic agent is not sufficient to express sufficient antistatic performance is that the antistatic agent is present in the fiber in a continuous state in a streak shape in the fiber axis direction. In that the compounded antistatic agent does not function effectively.

[0004]

The present invention provides a polyalkylene glycol and a metal salt of an organic sulfonic acid as antistatic agents,
Improving the method of producing antistatic polyester fiber by the so-called kneading method, which is blended at the polyester polycondensation stage,
In particular, the amounts of the polyalkylene glycol and the organic sulfonic acid metal salt used as the antistatic agent and the spinning method were examined, and an independent phase of the polyalkylene glycol continuous in the fiber axis direction was formed, so that the compounded antistatic agent functioned effectively. It is based on the discovery of obtaining an antistatic polyester fiber exhibiting high antistatic performance even with a small amount of antistatic agent, and an object of the present invention is to provide an antistatic property excellent in antistatic performance. It is to provide a polyester fiber.

[0005]

According to the present invention, there is provided a polyalkylene glycol having an average molecular weight of 5,000 or more.
% By weight and the general formula RSO ₃ M (where R is _{3 to 3} carbon atoms)
Ethylene terephthalate containing as an antistatic agent 0.1 to 2% by weight of an organic sulfonic acid metal salt represented by an alkyl group of 0, an aryl group or an alkylaryl group having 7 to 40 carbon atoms, and M represents an alkali metal. Is a fiber comprising a polyester polymer having as a main repeating unit, wherein the polyalkylene glycol forms a number of independent phases oriented in the fiber axis direction in the fiber, and each independent phase in the fiber cross section perpendicular to the fiber axis. The average spacing between phases is 0.1 μm or less, and the ratio of the number of discontinuous independent phases to the total number of independent phases oriented in the fiber axis direction per 1 μm ² in the fiber longitudinal section parallel to the fiber axis is 50%. The antistatic polyester fiber,

[0006] The polyester in the antistatic polyester fiber of the present invention refers to a polyester containing ethylene terephthalate as a main repeating unit, terephthalic acid or an ester-forming derivative thereof as a dicarboxylic acid component, and ethylene glycol or an ester-forming derivative thereof. Is a typical diol component, a part of the dicarboxylic acid component is a dicarboxylic acid component other than terephthalic acid or an ester-forming derivative thereof, and a part of the diel component is ethylene glycol or a derivative thereof. It may be replaced with another diol component other than the ester-forming derivative.

Other dicarboxylic acid components include isophthalic acid, 5-sulfoisophthalic acid monoalkali metal salt, naphthalenedicarboxylic acid, diphenyldicarboxylic acid, diphenylsulfondicarboxylic acid, adipic acid, sebacic acid, and 1,4-cyclohexanedicarboxylic acid. Dicarboxylic acids or esters thereof and p-oxybenzoic acid, p
And oxycarboxylic acids such as -β-oxyethoxybenzoic acid and esters thereof.

[0008] Other diol components include 1,4
-Butanediol, alkylene glycol having 2 to 10 carbon atoms, 1,4-cyclohexanedimethanol, neopentyl glycol, 1,4-bis (β-oxyethoxy)
Examples include benzene and bisglycol ether of bisphenol A.

Further, as long as the polyester is substantially linear, polycarboxylic acids such as trimellitic acid and pyromellitic acid, polyols such as pentaerythritol, trimethylolpropane and glycerin, monohydric polyalkylene oxide, phenyl A polymer using a polymerization terminator such as acetic acid may be used.

The polyester may be synthesized by any known method. For example, in the case of polyethylene terephthalate, terephthalic acid and ethylene glycol are directly esterified, a lower alkyl ester of terephthalic acid such as dimethyl terephthalate is transesterified with ethylene glycol, or terephthalic acid is ethylene oxide. To synthesize a glycol ester of terephthalic acid or a low polymer thereof, followed by polycondensation of the product by a conventional method.

Further, in synthesizing the polyester,
Known catalysts, antioxidants, color inhibitors, ether bond by-product inhibitors, flame retardants, and other additives may be appropriately used.

The polyester constituting the antistatic polyester fiber of the present invention contains 0.5 to 5% by weight of a polyalkylene glycol having an average molecular weight of 5,000 or more and a metal salt of an organic sulfonic acid 0 represented by the above general formula. 0.1 to 2% by weight as an antistatic agent. In the present invention, the polyalkylene glycol contained in the polyester needs to have an average molecular weight of 5,000 or more, and is preferably a polyalkylene glycol having an average molecular weight of 10,000 or more.

In the case of a polyalkylene glycol having an average molecular weight of less than 5,000, the proportion of the polyalkylene glycol copolymerized in the polyester main chain increases when added to the polyester polycondensation reaction system. , The formation of an independent phase as a polyalkylene glycol is reduced, and it is difficult to exhibit sufficient antistatic performance. Examples of the polyalkylene glycol include polyethylene glycol, polypropylene glycol, and a copolymer of ethylene oxide and propylene oxide.
It is not limited to these.

In the present invention, the organic sulfonic acid metal salt represented by the above general formula contained in the polyester includes sodium, potassium or lithium salts of alkyl sulfonic acids having 3 to 30 carbon atoms, toluene sulfone. Examples include an acid, a sodium salt, a potassium salt or a lithium salt of dodecylbenzenesulfonic acid, or a mixture thereof.

In the antistatic polyester fiber of the present invention, at least one polyalkylene glycol of the antistatic agent forms a large number of independent phases oriented in the fiber axis direction in the fiber. The glycol independent phase is a highly dispersed and continuous phase. In addition, the organic sulfonic acid metal salt is distributed near the polyalkylene glycol.

In the fiber, the independent phase of the polyalkylene glycol has an average spacing of 0.1 μm or less between each independent phase in a cross section of the fiber perpendicular to the fiber axis and is parallel to the fiber axis. The ratio of the number of discontinuous independent phases to the total number of independent phases oriented in the fiber axis direction per 1 μm ² in the longitudinal fiber cross section in the direction is less than 50%. The average spacing between the polyalkylene glycol independent phases is greater than 0.1 μm, or the proportion of discontinuous independent phases, ie, independent phases having a length of less than 1 μm is 50%.
If it is above, sufficient antistatic performance is not exhibited.

Hereinafter, a method for producing the antistatic polyester fiber of the present invention will be described. In the present invention, it is necessary to use a polyester polymer having ethylene terephthalate as a main repeating unit to which polyalkylene glycol and an organic sulfonic acid metal salt are added as an antistatic agent.

The amount of polyalkylene glycol added to the polyester must be 0.5 to 5% by weight, preferably 0.8 to 3% by weight. The amount added is 0.
If it is less than 5% by weight, the manifestation of antistatic performance becomes insufficient, and
If the amount is more than 10% by weight, not only the passing stability in the spinning process is lowered, but also the physical properties such as the strength and elongation of the obtained fiber are lowered.

When the polyalkylene glycol is added, it is preferable to use a small amount of a known stabilizer, antioxidant or the like in combination for the purpose of improving thermal stability. Examples thereof include hindered phenol compounds and thioether compounds. The addition amount of these compounds is 1 to polyalkylene glycol.
It is preferable that the content be 10 to 10% by weight.

The amount of the organic sulfonic acid metal salt added to the polyester must be 0.1 to 2% by weight.
Preferably it is 0.2 to 1.5% by weight. The amount added is 0.
If it is less than 1% by weight, the manifestation of antistatic performance becomes insufficient and
If the content exceeds the weight percentage, not only the passing stability in the spinning process is lowered, but also the resulting fiber has drawbacks such as fluffing.

In the present invention, the polyalkylene glycol and the metal salt of an organic sulfonic acid may be independently added to the polyester. However, it is preferable to add them as a mixture because they have a synergistic effect of antistatic performance. It is. The mixing ratio between the polyalkylene glycol and the organic sulfonic acid metal salt is as follows:
It is preferable to set the organic sulfonic acid metal salt to 90:10 to 10:90 in order to obtain a synergistic effect of antistatic performance.

The amount of the mixture of the polyalkylene glycol and the metal salt of the organic sulfonic acid to be added to the polyester is 0.5 to 5% by weight, preferably 1 to 4% by weight as the total amount of the mixture. If the total amount is less than 0.5% by weight, the antistatic performance will be insufficient, and if it exceeds 5% by weight, not only will the passing stability in the spinning process be reduced, but also the strong elongation of the resulting fiber. And other problems, such as deterioration of physical properties, and fluffing of fibers.

The addition of the mixture of the polyalkylene glycol and the metal salt of an organic sulfonic acid is preferably added to the reaction system before the completion of the polycondensation reaction of the polyester. Preferably, the polycondensation reaction is completed by adding in a molten state to the system in the middle of the polycondensation reaction.

In the present invention, the following requirements (A), (B) and (C) are satisfied when melt-spinning a polyester polymer to which a polyalkylene glycol and an organic sulfonic acid metal salt are added as an antistatic agent. Under the conditions, it is necessary to perform melt spinning from a spinneret. (A) the time required for the opening area S ₁ and the single-hole portion of the single-hole spinneret single pore volume V ₁ medium represented by the product of the length L ₂ to pass through the polymer is at least 3 ms (B ) Discharge linear velocity V ₀ of polymer from single hole of spinneret
Is 800 cm / min or less. (C) The ratio (V _sp / V ₀ ) of the winding speed (V _sp ) of the discharged yarn to the linear discharge speed V ₀ of the polymer from the single hole of the spinneret is 2
00 or more

In order for the polyester fiber to exhibit excellent antistatic performance, the dispersion state of the antistatic agent in the fiber obtained as described above is extremely important. The following method is used to disperse the alkylene glycol as a long and continuous continuous independent phase in the fiber axis direction.

In the present invention, polyalkylene glycol and an organic sulfonic acid metal salt are used as an antistatic agent.
The antistatic agent used in the present invention is incompatible with polyester in their molten state. Accordingly, by melt spinning the added polyester polymer antistatic agent when spun from a spinneret, a single hole having an opening area S ₁ and the area S ₁ of the single-hole spinneret length L ₂ By increasing the time required for the polymer to pass through the single-hole volume V ₁ indicated by the product, the antistatic agent immediately before discharge, particularly the phase separation between the polyalkylene glycol and the polyester becomes clearer, and immediately after discharge. A preferable state is formed in which the polyalkylene glycol is oriented in the fiber axis direction in the fiber thinning step.

In order to form a state in which the polyalkylene glycol is preferably oriented in the fiber axis direction, it is necessary that the time required for the polymer to pass through the single pore volume V _{1 be} 3 milliseconds or more. Preferably, it is 10 ms or more. In order to highly orient the polyalkylene glycol in the fiber axis direction, the polymer discharge linear velocity V ₀ at the time of discharging the polymer from a single hole of the spinneret is 800 c.
m / min or less, preferably 500 cm / min.
Minutes or less.

Further, the ratio of the winding speed of the discharge yarn and (V _sp) and the discharge line velocity V ₀ which polymers from single-hole spinneret (V
( _sp / V ₀ ) (ie, draft ratio) must be 200 or more, and preferably 400 or more.

As long as the spinneret used in the present invention can melt-spin a polymer under the conditions satisfying the requirements (A), (B) and (C), the shape of the single-hole opening is circular. Not only that, it may have a non-circular cross section, and may have a shape for obtaining hollow fibers.

In particular, in the present invention, when a polyester polymer to which an antistatic agent is added is melt-spun using a spinneret for solid fibers having a circular cross section, the following requirements (A ₁ )
It is preferable to perform melt spinning under the conditions satisfying (B ₁ ) and (C). (A ₁ ) The time required for the polymer to pass through the single-hole volume V ₁ represented by the product of the opening area S ₁ of the single hole of the spinneret and the length L ₂ of the single hole portion is 10 ms or more ( B ₁ ) Linear velocity V ₀ of discharge of polymer from single hole of spinneret
(C) The ratio (V _sp / V ₀ ) of the winding speed (V _sp ) of the discharged yarn to the linear discharge speed V ₀ of the polymer from the single hole of the spinneret is 2
00 or more

That is, in the spinneret for a solid fiber having a circular cross section, the time required for the polymer to pass through the single-hole volume V ₁ is 10 ms or more, more preferably 30 ms or more, Discharge linear velocity V ₀ of 600c
m / min or less, more preferably 400 cm / min or less, is desirable in order to obtain excellent antistatic performance and to obtain uniform fibers with extremely little staining spots.

The polyester fiber thus obtained may be subjected to a stretching treatment, heat treatment or shaping as necessary to obtain a processed yarn, or a known woven or knitted fabric subjected to alkali weight reduction processing or dyeing processing. The processing technology described above can be applied as appropriate.

[0033]

The present invention will be described below in more detail with reference to examples. The percentages, parts and mixing ratios in the examples mean weight%, parts by weight and weight ratio, respectively,
Indicates good, slightly good and bad, respectively, and each characteristic value was measured by the following method.

[Intrinsic Viscosity] A sample was dissolved in a phenol / tetrachloroethane (50/50) mixed solvent and measured at 25 ° C. with an Ubbelohde viscometer.

[Antistatic performance] Warp: polyethylene terephthalate fiber yarn (50 denier / 18 filaments) Weft: antistatic polyester fiber yarn (100 denier / 48 filaments, 75 denier / 36 filaments) Warp density: 40 yarns / cm Weft density: after weaving under conditions of 26.6 yarns / cm and 30.5 yarns / cm, JIS L1094 (1988)
The charged voltage and the decay rate were measured according to the triboelectric discharge curve measurement method of the reference method. The measurement was performed using a friction voltage meter EST-3 manufactured by Kanebo Engineering Co., Ltd.
The test was performed at 0 ± 1 ° C. and a relative humidity of 30 ± 2%. Washing of the sample, washing of the friction cloth with hot water, and adjustment of the sample and the friction cloth were based on the JIS method, and wool was used as the friction cloth.

For each sample, the charged voltage V after 30 seconds and the decay rate D after 60 seconds were determined as the average value of each of the five times from the triboelectric discharge curves obtained by measuring five times. Further, each sample was performed five times, and the final average values of the charged voltage V ₃₀ after 30 seconds and the decay rate D ₆₀ after 60 seconds were determined. The unit of the charged voltage is volt (V, the sign is minus (-)), and the attenuation rate is represented by%.

[Observation by Transmission Electron Microscope] The fibers obtained in Examples were dyed with an osmic acid aqueous solution, and then methyl methacrylate / butyl methacrylate (70/3).
0), an ultra-thin section was prepared, and the dispersion state of the antistatic agent in the fiber was determined using a JEM100CX-2 transmission electron microscope manufactured by JEOL Ltd. with the dispersion state of polyethylene glycol. And observed and shown in photographs. The dispersion state of the polyethylene glycol can be observed as black streaks in the photograph.

Example 1 100 parts of terephthalic acid and 52 parts of ethylene glycol were charged into an esterification tank.
The esterification reaction was carried out at 260 ° C. under a pressure of 5 kg / cm ² , and 0.01% of trimethyl phosphate, 0.04% of antimony trioxide and 0.4% of titanium dioxide were added to the obtained reaction product. It was added as a glycol solution and transferred to a polymerization tank. Next, when the polycondensation reaction was performed at 285 ° C. for 70 minutes under high vacuum, the molecular weight was 20,000.
Polyethylene glycol (hereinafter abbreviated as PEG) and sodium alkyl sulfonate having an average carbon number of 15 (hereinafter referred to as RS).
(Abbreviated as O ₃ Na) at a mixing ratio of 5: 1 was melt-added into the reaction system so as to be 3.5% with respect to the produced polymer.
Subsequently, a polycondensation reaction is performed for a predetermined time, and the intrinsic viscosity is 0.7
Thus, a polyethylene terephthalate polymer No. 6 was obtained.

The polymer was formed into chips by a conventional method and dried, and thereafter, a spinning temperature of 280 ° C. and a winding speed of 1400 were used using a solid fiber spinneret having a circular single-hole opening.
It was melt spun at m / min. The spinneret used had 48 single holes described below. Single hole opening S ₁ : 0.283 mm ² Single hole length L ₂ : 3.0 mm Single hole volume V ₁ : 0.849 mm ^{3 The} spinning conditions were as follows. Polymers transit time of a single pore in a volume V _1: 74.6 ms polymer discharge linear speed V _0: the ratio of the 241cm / min winding speed V _sp and the polymer discharge linear speed V ₀ (V _sp /
V _0): 581

Next, the undrawn yarn was drawn and heat-treated according to a conventional method to obtain a drawn yarn of 100 denier / 48 filaments. The obtained drawn yarn has a strength of 4.3 g / d,
The elongation was 30%, which was practically no problem, and was homogeneous without any staining spots.

The drawn yarn was woven by a conventional method, and the antistatic performance of the woven fabric was measured. The average charged voltage V ₃₀ after 30 seconds was 3700 V, and the average decay rate D ₆₀ after 60 seconds was 57%, which was extremely good. It showed excellent antistatic performance. In addition, the woven fabric is
%, The average charging voltage V ₃₀ was 3900 V, and the average decay rate D ₆₀ was 54%.
And that the antistatic performance was hardly reduced even after the alkali weight reduction processing.

When the fiber of the obtained drawn yarn was cut in the direction perpendicular to the fiber axis, the average spacing between the respective PEG independent phases in the fiber cross section was 0.029 μm,
When cut in a direction parallel to the fiber axis, the ratio of the number of discontinuous independent phases to the total number of independent phases oriented in the fiber axis direction per 1 μm ² in the fiber longitudinal section was 9%. FIGS. 3 and 4 show a transmission electron micrograph (magnification: 40,000 times, visual field: 1 μm ² ) of a fiber longitudinal section and a transmission electron micrograph (magnification: 40,000 times) of a fiber cross section.

(Examples 2 to 8, Comparative Examples 1 to 6) Example 1
In the same manner as in Example 1 except that the addition amount of the mixture of PEG and RSO ₃ Na, the spinneret and the spinning conditions in Example 1 were changed as described in Table 1, a drawn yarn was obtained and the antistatic performance of the woven fabric was measured. Table 2 shows the measured results.

[0044]

[Table 1]

[0045]

[Table 2]

When the fiber of the drawn yarn obtained in Comparative Example 2 was cut in a direction perpendicular to the fiber axis, the average interval between the respective PEG independent phases in the fiber cross section was 0.1 mm.
027 μm, and when cut in a direction parallel to the fiber axis, the ratio of the number of discontinuous independent phases to the total number of independent phases oriented in the fiber axis direction per 1 μm ² in the fiber longitudinal section was 84%. there were. Comparative Example 2 is shown in FIGS.
A transmission electron micrograph (magnification: 40,000 times, visual field: 1 μm ² ) of a fiber longitudinal section and a transmission electron micrograph (magnification: 40,000 times) of a fiber cross section are shown.

Example 9 100 parts of terephthalic acid and 52 parts of ethylene glycol were charged into an esterification tank.
The esterification reaction was carried out at 260 ° C. under a pressure of 0 kg / cm ² , and 0.01% of trimethyl phosphate, 0.04% of antimony trioxide and 0.46% of titanium dioxide were added to the obtained reaction product. It was added as a glycol solution and transferred to a polymerization tank. Next, when the polycondensation reaction was performed at 285 ° C. for 70 minutes under high vacuum, the molecular weight was 20,000.
A mixture of PEG and RSO ₃ Na at a mixing ratio of 50:50 was melt-added to the reaction system so as to have a concentration of 2.0% with respect to the produced polymer. Of polyethylene terephthalate polymer was obtained.

After the polymer was formed into chips by a conventional method and dried, a spinning temperature of 283 ° C. and a winding speed of 1400 were applied using a solid fiber spinneret having a circular single-hole opening.
It was melt spun at m / min. The spinneret used has 36 single holes described below. Single hole opening S ₁ : 0.283 mm ² Single hole length L ₂ : 3.0 mm Single hole volume V ₁ : 0.849 mm ^{3 The} spinning conditions were as follows. Polymer passage time in single pore volume V ₁ : 56 ms Polymer discharge linear velocity V ₀ : 181 cm / min Ratio of winding speed V _sp to polymer discharge linear velocity V ₀ (V _sp /
V _0): 773

Next, the undrawn yarn was drawn and heat-treated according to a conventional method to obtain a drawn yarn of 76 denier / 36 filaments. The obtained drawn yarn had a strength of 4.5 g / d, an elongation of 32%, and was homogeneous without any staining spots or the like.

The drawn yarn was woven by a conventional method, and the antistatic performance of the woven fabric was measured. The average charged voltage V ₃₀ after 30 seconds was 4200 V, and the average decay rate D ₆₀ after 60 seconds was 68%, which was extremely good. It showed excellent antistatic performance. In addition, the woven fabric is
%, The average static voltage V ₃₀ was 4500 V, and the average decay rate D ₆₀ was 64%.
And that the antistatic performance was hardly reduced even after the alkali weight reduction processing.

(Examples 10 to 14, Comparative Examples 7 to 11) The mixing ratio, addition amount, spinneret and spinning conditions of the mixture of PEG and RSO ₃ Na in Example 9 were changed as shown in Table 3. Except for the above, a drawn yarn was obtained in the same manner as in Example 9 and the antistatic performance of the woven fabric was measured. The results are shown in Table 3.

[0052]

[Table 3]

[0053]

According to the present invention, a polyalkylene glycol and a metal salt of an organic sulfonic acid are used as an antistatic agent, and the polyalkylene glycol in the fiber is elongated in the fiber axis direction with a relatively small amount of the antistatic agent. It is possible to orient and disperse as a streak-like continuous phase, and by sufficiently exhibiting the function of the antistatic agent, it is possible to provide an antistatic polyester fiber having extremely excellent antistatic performance. In addition, a uniform antistatic polyester fiber having no staining spots or the like can be obtained with good yarn production stability.

[Brief description of the drawings]

FIG. 1 is a transmission electron micrograph (magnification: 6,000) of a longitudinal section of a fiber showing the dispersion state of polyethylene glycol in the antistatic polyester fiber obtained in Example 1.
Times).

FIG. 2 is a transmission electron micrograph (magnification: 6,000) of a fiber longitudinal section showing the dispersion state of polyethylene glycol in the antistatic polyester fiber obtained in Comparative Example 2.
Times).

FIG. 3 is a transmission electron micrograph (magnification: 40, 0) of a longitudinal section of the antistatic polyester fiber obtained in Example 1.
The magnification is 00 and the visual field is 1 μm ² ).

FIG. 4 is a transmission electron micrograph (40,0 magnification) of a cross section of the antistatic polyester fiber obtained in Example 1.
00 times).

FIG. 5 is a transmission electron micrograph (magnification: 40, 0) of a longitudinal section of the antistatic polyester fiber obtained in Comparative Example 2.
The magnification is 00 and the visual field is 1 μm ² ).

FIG. 6 is a transmission electron micrograph (40,0 magnification) of a cross section of the antistatic polyester fiber obtained in Comparative Example 2.
00 times).

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Noboru Imabayashi 4-1-1 Ushikawadori, Toyohashi-shi, Aichi Prefecture Inside the Toyohashi Plant of Mitsubishi Rayon Co., Ltd. (72) Inventor Hideto Kakita 20 Miyukicho, Otake City, Hiroshima Prefecture No. 1 Mitsubishi Rayon Co., Ltd. Central Research Laboratory (72) Inventor Yasuyuki Fujii 20-1 Miyukicho, Otake City, Hiroshima Prefecture Mitsubishi Rayon Co., Ltd. Central Research Laboratory

Claims (1)

[Claims] 1. A polyalkylene glycol having an average molecular weight of 5,000 or more, 0.5 to 5% by weight, and a general formula RSO ₃ M
(Where R is an alkyl group having 3 to 30 carbon atoms, 7 to
A polyester polymer containing ethylene terephthalate as a main repeating unit containing 0.1 to 2% by weight of an organic sulfonic acid metal salt represented by the following formula: Wherein the polyalkylene glycol forms a large number of independent phases oriented in the fiber axis direction in the fiber, and the average interval between the independent phases in the fiber cross section perpendicular to the fiber axis is 0.1 μm or less. And 1 μm in the fiber longitudinal section parallel to the fiber axis.
^{2. An} antistatic polyester fiber, wherein the ratio of the number of discontinuous independent phases to the total number of independent phases oriented in the fiber axis direction per ² is less than 50%.