JPH11229276A - Polyester fiber having excellent processability - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain polyester fibers having excellent smoothness, coherency, antistaticity and heat resistance, having extremely good unwindability from bobbins or cheeses in a winding process or in a drawing process and extremely good process passableness from a spinning process to a false twisting process especially on a false twisting treatment, or the like. SOLUTION: The polyester fibers having excellent processability comprises a polytrimethylene terephthalate in an amount of >=85 wt.%, and has a birefringence of >=0.025, an elongation of 20-180%, an elastic modulus of 20-50 g/d, a fiber friction cutting number of >=300, an interfilament static friction coefficient of 0.2-0.4 and an oil adhesion rate of 0.2-3 wt.%. The false-twisted yarns of the polyester fibers are suitable for clothes having good qualities such as good softness, bulkiness and uniformity in the forms of woven or knitted fabrics.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention has excellent smoothness, convergence, antistatic properties and heat resistance, and has a winding step, a stretching step,
The present invention relates to a polyester fiber having extremely good processability from spinning to processing, such as spinning properties from bobbins and cheese, particularly processing properties.

[0002]

2. Description of the Related Art Polytrimethylene terephthalate obtained by polycondensing a lower alcohol ester of terephthalic acid represented by terephthalic acid or dimethyl terephthalate with trimethylene glycol (1,3-propanediol) has a low elastic modulus. (Soft texture), excellent elastic recovery, easy dyeing properties similar to polyamide, and breakthrough properties similar to polyethylene terephthalate such as light resistance, heat setting, dimensional stability, low water absorption It is a polymer, and it is applied to BCF carpets, brushes, tennis guts, etc. by taking advantage of its characteristics (JP-A-9-3724, JP-A-8-173244, JP-A-5-262882).

In general, woven or knitted fabrics used as clothing require physical crimping or the use of specially structured fibers such as side-by-side yarns and hetero-shrinkage mixed yarns in order to exhibit their soft properties (bulkness). It is. The physical crimping method includes a buckling type crimping method in which fibers are forcibly fed into a box, and a nozzle in which a turbulent air flow is generated by utilizing air turbulence. A method of making a loop-shaped crimp by physically disturbing the multifilament by feeding fibers to the fiber, twisting in the middle between a pair of rolls, and twisting the fiber upstream of the portion to be twisted by 170- 220 ° C
There is known a method in which a reverse twist is applied downstream of the heat setting and untwisted to give a false twist as a whole without a true twist being applied.

[0004] This method of giving a false twist is generally called false twisting. When a drawn yarn is used as the yarn to be supplied, only the bulkiness is imparted without substantial stretching in the false twisting step. be called. When partially oriented yarn (POY) is used as the supply yarn, drawing is performed simultaneously in the false twisting step, and thus the obtained yarn is called a draw textured yarn (DTY). Regarding the yarn to be false-twisted as described above, when performing false-twisting from spun irrespective of the drawn yarn or POY, an oil agent adheres to the fiber surface for the purpose of not causing fluff on the fiber and preventing yarn breakage. Is essential.

That is, it is necessary that the oil agent to be attached to the fiber during the false twisting process not only allows the spinning and drawing processes to proceed smoothly, but also satisfies all the properties required in the false twisting process. is there. Among the properties of oils that govern the performance required in these various processes, the most important ones are friction at high temperature in the false twisting process, so smoothness, convergence, antistatic (antistatic) , Heat resistance is required. However, these properties tend to contradict each other in view of the properties of various components constituting the oil agent.
For example, when the amount of the highly viscous component is increased in order to improve the convergence and the heat resistance, the smoothness is reduced. Conversely, if the proportion of the low-viscosity component is increased in order to increase the smoothness, the convergence and the heat resistance are reduced.

Further, it is known that the performance expected from each component of the oil agent is greatly affected by the polymer constituting the fiber and its physical properties. For example, since polytrimethylene terephthalate fiber has a similar molecular structure to polyethylene terephthalate fiber, one might imagine that the same oil agent as polyethylene terephthalate fiber can be used industrially. However, the same oil agent cannot be applied to polytrimethylene terephthalate fibers because they have greatly different physical properties from polyethylene terephthalate fibers. In particular, since the elastic modulus of the polytrimethylene terephthalate fiber is as low as a fraction of the elastic modulus of the polyethylene terephthalate fiber, only a low tension is applied when it comes into contact with the metal surface or resin surface, or between yarns, or between filaments. Because the fiber is easily deformed even in the state,
There is a disadvantage that the contact surface is widened, the friction is increased and the tension is increased, and as a result, yarn breakage and fluff are extremely likely to occur. In particular, the frequency of occurrence of yarn breakage and fluff in the false twisting stage tends to be high.

It is very common to apply an oil agent to polyethylene terephthalate fiber, but since the elastic modulus is different from that of polytrimethylene terephthalate, these problems naturally occur even if the oil agent used for the fiber is applied as it is. Not only is the point not solved, but it is impossible to bring out the soft texture of the polytrimethylene terephthalate fiber. As described above, in order to satisfy all the demands for the oil agent, it is necessary to prevent each component of the oil agent from exhibiting inconsistent performance and at the same time, while considering the polymer and physical properties of the fiber, It is necessary to find a technique for blending the constituent components in a specific amount and thereby exerting a synergistic effect.

[0008]

SUMMARY OF THE INVENTION The object of the present invention is to provide excellent smoothness, convergence, antistatic properties and heat resistance, a winding step, a stretching step, a debinding property from bobbins and cheese, In particular, it is an object of the present invention to provide a polyester fiber having extremely good processability from spinning to false twisting such as false twisting.

[0009]

Means for Solving the Problems The present inventors have focused on a specific parameter as a surface characteristic reflecting the physical properties, smoothness, convergence, heat resistance and the like of polytrimethylene terephthalate fiber, and set this within a specific range. The inventors have found that the setting can solve the problem of the present invention, and as a result of further detailed investigation, have reached the present invention. That is, the present invention relates to a polyester fiber comprising 85% by weight or more of polytrimethylene terephthalate, a birefringence of 0.025 or more, an elongation of 20 to 180%, an elasticity of 20 to 50 g / d, and the number of times of yarn friction cutting. The present invention provides a polyester fiber having excellent workability, characterized in that an oil agent is adhered at a static friction coefficient between filaments of 0.2 to 0.4 and an oiling rate of 0.2 to 3% by weight at least 300 times. Things.

In the present invention, 85% by weight or more of the polymer constituting the polyester fiber is composed of terephthalic acid and 1,3.
-Polytrimethylene terephthalate obtained by polycondensation of trimethylene glycol. One or more other copolymers or polymers may be copolymerized or blended in a range that does not impair the purpose of the present invention, that is, in a range of 15% by weight or less. Examples of such comonomers and polymers include oxalic acid, succinic acid, adipic acid, isophthalic acid, phthalic acid, 2,6-naphthalenedicarboxylic acid, cyclohexanedicarboxylic acid, ethylene glycol, butanediol, cyclohexanedimethanol, and
-Sodium sulfoisophthalic acid, tetrabutylphosphonium 5-sulfoisophthalate, polyethylene glycol, polyethylene terephthalate, polybutylene terephthalate and the like.

If necessary, various additives such as a matting agent, a heat stabilizer, a defoaming agent, a flame retardant, an antioxidant, an ultraviolet absorber, an infrared absorber, a crystal nucleating agent, and a fluorescent enhancer. A whitening agent or the like may be copolymerized or mixed. The intrinsic viscosity [η] of the polyester fiber of the present invention is 0.4 to 2.0, preferably 0.5 to 1.5, and more preferably 0.6 to 1.2.
Range. Within this range, a fiber having excellent strength and spinnability can be obtained. If the intrinsic viscosity is less than 0.4,
Since the melt viscosity of the polymer is too low, spinning becomes unstable, and the strength of the obtained fiber is also low and unsatisfactory. Conversely, if the intrinsic viscosity exceeds 2.0, the melt viscosity is too high because the melt viscosity is too high. Fracture or poor spinning occurs.

The polyester fiber of the present invention has a birefringence of 0.025 or more, an elongation of 20 to 180%, and an elasticity of 20 to 5%.
It must be 0 g / d. When the polyester fiber of the present invention has physical properties in this range, the number of times of yarn friction cutting and the coefficient of static friction between filaments, which are parameters reflecting the smoothness and convergence of the fiber described later, are controlled to specific values. In combination with the excellent low modulus of elasticity of polytrimethylene terephthalate fiber, good mechanical properties and elastic recovery, and the bulkiness by false twisting, it is possible to maximize the softness of the woven and knitted fabric after processing. It is possible to bring out excellent effects such as natural texture, bulkiness and homogeneity.

First, the polyester fiber of the present invention has a birefringence of 0.025 or more. By setting the birefringence in this range, the molecules in the fiber are oriented to some extent, so that even if a high temperature is applied during the processing, the false twisting processability is improved without fusing. If the birefringence is less than 0.025, the orientation of the molecules is too low, and the fibers are partially melted by false twisting, so that yarn breakage or fluff is likely to occur. Preferably, it is 0.025 to 0.1 from the viewpoint of excellent false twistability.

Second, the elongation of the polyester fiber of the present invention needs to be 20 to 180%. By setting the elongation within this range, without causing fluff or yarn breakage,
False twisting becomes easier. If it exceeds 180%, fluff and yarn breakage tend to occur in the false twisting stage. Since the crystal elongation of polytrimethylene terephthalate is at least 20%, it is impossible to achieve an elongation of less than 20%. The preferred elongation is preferably from 30 to 120% from the viewpoint of false twisting workability.

Third, the elastic modulus of the polyester fiber of the present invention is 20 to 50 g / d. By setting the elastic modulus in this range, a soft texture and bulkiness can be exhibited when the fabric is used. If the elastic modulus exceeds 50 g / d, a soft texture cannot be obtained when the fabric is used. Further, when the elastic modulus is less than 20 g / d, when the fabric is used, the fabric is merely a rigid fabric. Preferably, it is 20 to 40 g / d from the viewpoint of providing appropriate softness.

The present inventors set the number of times of thread friction cutting and the coefficient of static friction between filaments as structural parameters reflecting the smoothness, bunching, antistatic properties and heat resistance of the polyester fiber of the present invention. The polyester fiber of the present invention, in order to ensure sufficient stability in the process from spinning to false twisting, the number of times of yarn friction cutting is 300 or more, the static friction coefficient between filament and filament is 0.2 to 0.4,
It is necessary that the oil agent adheres at an oiling rate of 0.2 to 3% by weight. The methods for measuring these parameters are described in detail in the examples.

The number of times of thread friction cutting is a parameter indicating a measure of the likelihood of fluffing when the yarn is rubbed with each other. When the number of times of thread friction cutting is 300 or more,
Even when a force is applied to the yarns and the filaments during the false twisting process and the contact area increases due to the low elastic modulus of the fiber, yarn breakage and fluff are less likely to occur. Also, using the obtained false twisted yarn, unevenness in the structure of the fine fabric during knitting and weaving is unlikely to occur, and it is possible to maximize the uniformity, soft texture, and bulkiness of the fabric. Become. If the number of times of yarn friction cutting is less than 300, fluff or scum (modified polymer scraps or oils produced by rubbing of fibers) on the heater is likely to occur during false twisting. Preferably, the number is 700 or more, more preferably 800 or more, particularly preferably 1000 or more.

The coefficient of static friction between filaments is the coefficient of static friction when yarns and filaments come into contact with each other in a filament manufacturing process and a subsequent false twisting process. This parameter is the most important parameter that reflects the smoothness and convergence of the polyester fiber of the present invention.By combining this parameter with the specific physical property values of the polytrimethylene terephthalate fiber, the excellent characteristics of the fiber can be derived, It is possible to maximize the uniformity, soft texture, strength, surface properties and bulkiness of the twisted fabric. If this value exceeds 0.4, the frictional resistance is too large, and the yarn breaks or fluffs during false twisting. If it is less than 0.2, the frictional resistance is too low, so that the yarn of the pan or cheese is liable to fall off, and the wound form is apt to collapse. Preferably, 0.25-
0.35.

The oiling ratio of the oil agent is 0.2 to 3% by weight.
If the oiling rate is more than 3% by weight, the resistance of the yarn becomes too large or scum tends to be generated by adhering to rolls, hot plates, guides, etc. Conversely, if it is less than 0.2% by weight, the effect is obtained. It becomes difficult to be. Preferably it is 0.5 to 1.1% by weight.

The most preferred constituents of the oil agent used in the polyester fiber of the present invention are polyether for improving the smoothness, convergence, lubricity and heat resistance of the fiber, and antistatic and emulsifying properties. An oil agent comprising an ionic surfactant and / or a non-ionic agent for enhancing. The proportion of these components in the total amount of the oil agent is such that the polyether is 50 to 98% by weight, preferably 60 to 90% by weight, and the ionic and / or nonionic surfactant is 2 to 2% by weight.
It is 50% by weight, preferably 20 to 40% by weight. If the polyether exceeds 90% by weight or is less than 10% by weight, scum tends to occur. Ionic surfactant and / or
When the amount of the nonionic surfactant exceeds 50% by weight, the smoothness is impaired, and fluff is easily generated. When the amount is less than 20% by weight, antistatic properties are insufficient, and as a result, fuzz is easily generated. Also, as other trace oil component, an emulsifier, a preservative, a rust inhibitor, an antioxidant, an oil film strengthening agent (metal soap, phosphate salt) or the like may be contained in an amount of 10% by weight or less.

The polyether used as the base oil of the oil agent used in the present invention has a molecular weight of from 1,000 to 20,000, preferably from 1,000 to 20,000 from the viewpoint of good smoothness and heat resistance.
10,000. If the molecular weight is less than 1,000, smoke is generated in the false twisting step, and the tar substance adheres to the heater to cause thread breakage and fluff. On the other hand, if it exceeds 20,000, the smoothness is reduced. Specific examples of these polyethers include alcohols (saturated alcohols having 1 to 18 carbon atoms, oleyl alcohol, monohydric alcohols such as synthetic alcohols having 10 to 15 carbon atoms, reduced alcohol, hexadecanol, etc .; 12 diols, glycerin,
Polyhydric alcohols such as trimethylolpropane. Alkyl phenols), carboxylic acids (capric acid, adipic acid, trimellitic acid, etc.), amine compounds (laurylamine, ethylenediamine, triethanolamine, etc.),
Ring-opening addition polymerization of a thioether compound or mercaptan compound (thioglycol, triethylene glycol dimercaptan, etc.) with a cyclic ether monomer such as ethylene oxide, propylene oxide, butylene oxide or tetrahydrofuran in the presence of a catalyst in a block or random manner. And those obtained by etherifying or silylating these terminal hydroxy groups.

It is also effective to use an ester compound and / or a mineral oil in combination with the polyether as a lubricant component. These ester compounds and / or mineral oils are not particularly limited as long as they have a substantial effect as a lubricant / frictional resistance reducing agent. Mono- or diesters of aliphatic alcohols and monohydric aliphatics, mono- or diesters of polyoxy (ethylene / propylene) aliphatic alcohols and mono- or dihydric fatty acids, purified mineral having a Redwood viscosity at 30 degrees of 40 to 200 seconds Oil is preferred.

Examples of the ionic surfactant include anionic surfactants, cationic surfactants, and amphoteric surfactants. In particular, use of anionic surfactants is effective in preventing static electricity, abrasion resistance, and emulsification. It is preferable from the viewpoint of imparting properties and rust prevention, and specific examples include higher alcohols, higher alcohols to which ethylene oxide is added, or phosphoric acid ester salts of alkylphenols or various sulfonate salts. Of course, two or more kinds of anionic surfactants may be combined. In addition, a nonionic surfactant is necessary for imparting emulsifying properties, yarn bundling properties, oil agent adhesion, and abrasion resistance. Examples thereof include polyoxyethylene alkyl ether, polyoxyethylene alkyl aryl ether, and polyoxyethylene alkyl aryl ether. Specific examples include oxyethylene-added alcohol fatty acid esters.

In particular, in order to greatly improve the number of times of yarn friction cutting, polypropylene oxide / ethylene oxide is used as a component of polyether in a weight ratio of 20/80 to 20/80.
It is preferable to use 1 to 20% by weight of a 50/50 polyether having a molecular weight of 1,000 to 20,000, preferably 10,000 to 15,000. Since the polyether can impart sufficient smoothness to the fiber at a high temperature, the number of times of yarn friction cutting can be greatly improved, and a smoother false twisting property can be added. However, since the polyether increases the filament-filament static friction coefficient, it accounts for 1% of the total amount of the oil agent.
-20% by weight, preferably 3-10% by weight. Further, it is preferable that the content of the nonionic surfactant is 1 to 20% by weight, preferably 3 to 10% by weight.

The ratio of polypropylene oxide / ethylene oxide must be 20/80 to 50/50 by weight, preferably 30/70 to 50/50.
If it is less than 20/80, heat resistance will be poor. If it exceeds 50/50, the viscosity becomes too high, and the smoothness is impaired. The oil agent adjusted as described above can be adhered to the fiber as a straight oil agent or as an emulsion oil agent by dispersing it in water at 5 to 60% by weight, preferably 5 to 35% by weight. As a method for applying the oil agent, a known method can be used. For example, in a step of cooling a molten multifilament extruded from a spinneret into a solid multifilament and winding it up at 1000 to 6000 m / min, a solid filament is formed. After that, the oil agent is applied one or more times by using a known method such as a normal roller lubrication method or a nozzle lubrication method.

The polyester fiber of the present invention thus obtained is false-twisted or drawn false-twisted by using a known method to obtain a false-twisted yarn. The obtained false twisted yarn is processed into a woven or knitted material using a known method, but when flowing into the weaving and knitting step with the oil agent used in the false twisting attached at this time, the smoothness is too low, A large amount of fluff is generated. Therefore, at the stage where the false twisting is completed, it is necessary to separately apply an oil agent suitable for weaving and knitting. The preferred composition of the oil agent in such a weaving and knitting step is 80 to 10% by weight of an aliphatic ester and / or a mineral oil, and 20 to 90% by weight of an ionic surfactant and a nonionic surfactant. It is particularly preferable to apply the oil at an oiling rate of 0.5 to 2% by weight.

[0027]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in more detail with reference to examples and the like, but needless to say, the present invention is not limited to the examples and the like. The main measured values in the examples were measured by the following methods. (1) Intrinsic Viscosity This intrinsic viscosity [η] is a value determined based on the following definition formula. Ηr in the definition formula is 35 ° C. of a diluted solution of the polyester polymer dissolved in o-chlorophenol having a purity of 98% or more.
Is divided by the viscosity of the solvent itself measured at the same temperature, and is defined as a relative viscosity. C is the solute weight value in grams in 100 ml of the solution.

(2) Redwood viscosity Measured according to JIS-K2283-1956. (3) High elongation The high elongation of the yarn was measured according to JIS-L-1013. (4) Birefringence The birefringence of the yarn was determined from the retardation of polarized light observed on the fiber surface using an optical microscope and a compensator.

(5) Number of times of yarn friction cutting The number of times of yarn friction cutting was measured using a yarn friction binding force tester (No. 890) manufactured by Toyo Seiki Seisaku-sho, Ltd. The two ends of the yarn were tied together with two clasps lined up through pulleys. This clasp can reciprocate with a 20 mm stroke length. Rotate the pulley and twist twice, 2g
The clamp was reciprocated at 150 strokes / min under a tension of / d. The number of reciprocating movements can be measured by a counter, and the number of times until the yarn is cut was determined as the number of times of yarn friction cutting.

(6) Filament / filament static coefficient of friction A fiber having a static friction coefficient of about 690 m is wrapped around a cylinder at a twill angle of 15 ° for about 10 m.
g, and wrapped with the same fiber 30.5c as described above.
m was hung on a cylinder around which the fiber was wound. At this time, the fiber was hung so as to be perpendicular to the axis of the cylinder. Then, a weight having a load (g) of 0.04 times the total denier of the fiber laid on the cylinder was tied to one end of the fiber laid on the cylinder, and a strain gauge was connected to the other end. Next, the cylinder is rotated at a peripheral speed of 0.016 mm / sec, and the tension is measured with a strain gauge. The filament-filament static friction coefficient f was determined from the tension thus measured in accordance with the following equation. f = 1 / π × ln (T2 / T1) where T1 is the weight (g) of the weight applied to the fiber, T2 is the average tension (g) measured at least 25 times, ln is the natural logarithm, and π Indicates pi.

(7) Oiling rate The fiber was washed with ethyl ether, the ethyl ether was distilled off, and the amount of the pure oil adhering to the fiber surface divided by the fiber weight was taken as the oiling rate. (8) Generation of Fluff The presence or absence of fluff on the end face of the false twisted yarn cheese (2 kg wound) obtained after 10 days of operation under the conditions of Example 1 was visually observed and evaluated according to the following criteria. ：: not generated △: generated 1 or 2 ×: generated 3 or more (9) Evaluation of heater contamination After continuous operation for 10 days under the conditions of stretch false twist of Example 1, the yarn path of the twisting side heater The presence or absence of tar and scum was observed with a magnifying glass and evaluated according to the following criteria. ○: Almost no heater contamination ×: Heater contamination is observed

Reference Example 1 Dimethyl terephthalate and 1,
3-propanediol was charged at a molar ratio of 1: 2, titanium tetrabutoxide corresponding to 0.1 wt% of the theoretical polymer amount was added, and the temperature was gradually raised to complete the transesterification at 240 ° C. Titanium tetrabutoxide was further added to the obtained transesterified product at 0.1 wt% of the theoretical polymer amount, and reacted at 250 ° C. for 3 hours. The intrinsic viscosity of the obtained polymer was 0.8.

[0033]

Examples 1 to 5 The polymer obtained in Reference Example 1 was dried under a nitrogen atmosphere at 160 ° C. for 3 hours using a circulating drier to a water content of 50 ppm. The obtained dried polymer is put into an extruder and extruded at 270 ° C., 100 ° C., 5 cm
After passing through the heat retention area, the oil agent shown in Table 1 was adhered to the yarn as a 10% water-dispersed emulsion using an oil supply nozzle, and 3300.
It was wound at m / min. The birefringence of the obtained POY was 0.059, the strength was 2.5 g / d, the elongation was 71%, and the elastic modulus was 20 g / d.

The obtained fiber was subjected to a yarn running speed of 40 using a triaxial friction system (solid disk ceramic system).
Stretch false twisting was performed at a target twist number of 3200 T / m using a twisting side heater at 195 ° C. at 0 m / min, a stretching ratio of 1.5, and 2 m. Before winding the obtained false twisted yarn of 150d / 100f, 40% by weight of paraffin having a wood red viscosity of 130 seconds, 30% by weight of isooctyl stearate, and 8% by weight of a sodium salt of an alkane sulfonate having 15 to 16 carbon atoms. 0.5% oil solution consisting of 22% by weight of oleyl ether connected with 10 units of polyoxyethylene.
% By weight. Table 1 shows the test results of the obtained fibers. Fibers obtained using the oil agent of the present invention have excellent spinnability,
Degradability and workability were shown. The obtained false twisted yarn is passed through 6
Twill was woven at a density of 6 lines / inch and a weft of 64 lines / inch. In each of the examples, a homogeneous woven fabric having a soft feeling and a bulky feeling was obtained.

[0035]

Comparative Examples 1 to 4 Example 1 was repeated using the same method as in Example 1 except that only the oil agent was changed as shown in Table 1.
Fibers outside the scope of the present invention tended to cause fluff and heater contamination. Table 1 shows the test results of the obtained fibers. When weaving was carried out in the same manner as in Example 1, streaks were partially observed, and although there was a soft feeling, the fabric was partially lacking in bulkiness.

[0036]

[Table 1]

[0037]

COMPARATIVE EXAMPLE 5 Polyethylene terephthalate to which 0.8% by weight of the oil agent of Example 3 had been adhered and had a P of 150d / 100f
OY was created. At this time, it was necessary to set the twisting side heater to 210 ° C. in order to apply twist. Obtained PO
The number of times of Y friction cutting was reduced to 235 times, and some fluff was generated. Further, when a twill similar to that of Example 1 was prepared, it was bulky but had a firm texture and lacked homogeneity.

[0038]

Example 6 Polytrimethylene terephthalate drawn yarn (150d / 96f, strength 4.5g / d, elongation 25%,
The oil agent of Example 1 was attached to an elastic modulus of 28 g / d), and false twisting was performed in the same manner as in Example 1 without stretching. The obtained false twisted yarn had the number of times of thread friction cutting of 1,420, the filament / filament static friction coefficient was 0.31, and the false twistability was good. In addition, the obtained twill was a uniform woven fabric having a soft feeling and a bulky feeling.

[0039]

The polytrimethylene terephthalate fiber of the present invention has excellent smoothness, convergence, antistatic properties, and heat resistance, and has a winding process, a stretching process, a debinding property from bobbins and cheese, In particular, the processability from spinning to false twisting, such as false twisting properties, is extremely good. In addition, the false twisted yarn of the polyester fiber is soft, bulky as a woven or knitted fabric,
It is suitable for clothing applications having good quality such as homogeneity.

Claims (3)

[Claims] 1. A polyester fiber comprising at least 85% by weight of polytrimethylene terephthalate, having a birefringence of 0.025 or more, an elongation of 20 to 180%, and an elasticity of 20 to 180%.
Processability characterized by 50 g / d, 300 or more times of thread friction cutting, filament-filament static friction coefficient of 0.2 to 0.4, oiling rate of 0.2 to 3% by weight, and oil attached. Excellent polyester fiber. 2. An oil agent comprising 50 to 98% by weight of a polyether having a molecular weight of 1,000 to 20,000 and 2 to 50% by weight of an ionic surfactant and / or a nonionic surfactant. Item 10. The polyester fiber according to Item 1. 3. One component of the polyether is polypropylene oxide / ethylene oxide in a weight ratio of 20/8.
The polyester fiber according to claim 2, wherein the polyester fiber contains 1 to 20% by weight of a polyether having a molecular weight of 0 to 50/50 and a molecular weight of 10,000 to 20,000.