JPH1193022A - Polyester based conjugate fiber - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prepare a polyester based conjugate fiber dyeable with dispersed dye at below 110 deg.C, manifesting >=70% elastic recovery at 20% elongation, <=40 g/d elastic modulus excellent in heat setting properties and high in destaticizing properties. SOLUTION: This conjugate fiber is constituted from a polyester sheath part comprising terephthalic acid as acid component and trimethyleneglycol as glycol component, a polyester core component comprising terephathalic acid as acid component and trimethyleneglycol or ethyleneglytcol as glycol component, and a destaticizing agent comprising a copolymer containing 10 to 80 wt.% of polyethleneglycol having a molecular weight of 4000 to 20000 or a polyester based polymer dispersed with this destaticizing agent. The weight ratio of the destaticizing agent in the total fiber is 0.1 to 10 wt.%, the peak temperature of the dissipation factor of the sheath-core conjugate fiber is 85 to 115 deg.C, and the elastic modulus Q(g/d) and the elastic recovery R(%) satisfies 0.18<=Q/R<=0.35.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polyester composite fiber. More specifically, the present invention relates to a polyester-based composite fiber having both characteristics of a nylon fiber and a polyester fiber, having a low elastic modulus, a high elastic recovery property, an excellent heat setting property, a light resistance, and an antistatic property. .

[0002]

2. Description of the Related Art Nylon fibers are widely used in the field of clothing and materials by utilizing their low elastic modulus, high elastic recovery, antistatic properties, and low-temperature dyeability. In the garment field, it is widely used in women's innerwear and pantyhose fields where strong softness is required by taking advantage of its characteristics of antistatic properties and low elastic modulus, for example, mixed with stretch fibers represented by polyurethane fibers. ing. In the field of materials, nylon fibers are used for carpets, fishing nets, canvas, etc. because of their excellent elastic recovery and resistance to bending and friction.

[0003] Further, with respect to the problem of post-processing properties, since nylon fibers are dyeable at low temperatures, for example, when nylon fibers and cellulose fibers are mixed, heat resistance is low for dyeing the cellulose fibers. Using a reactive dye and combining it with an acid dye, one-step one-bath dyeing at normal pressure can be performed. Also, wool, silk, polyurethane fiber,
At a dyeing temperature exceeding 110 ° C. such as acetate fiber, when mixed with a fiber which is susceptible to thermal deterioration, it has excellent processing characteristics that dyeing is possible without damaging the fiber.

As described above, nylon fibers have a low elastic modulus,
Taking advantage of the characteristics of high elastic recovery, antistatic properties and low-temperature dyeability, despite having a large market among synthetic fibers, it also has the following serious problems. In other words, nylon fibers have poor heat-setting properties.For example, knitted fabrics such as tricots and Russells mixed with stretch fibers are prone to so-called laughter when used for a long period of time. The resulting fabric is poor. In addition, there is also a problem that yellowing is apt to occur when used for a long period of time or exposed to excessive sunlight due to poor light resistance.

[0005] On the other hand, polyester fibers represented by polyethylene terephthalate fibers are excellent in heat setting property and weather resistance, but have a high elastic modulus, a hard feeling, a poor elastic recovery property, and a high temperature. It has the opposite performance to nylon fibers, such as the need for dyeing. In addition, when the polyester fiber alone is used because it has no antistatic property, or when the mixing ratio of the cellulose fiber is low even in the mixed fabric with the antistatic cellulosic fiber, charging occurs, and it is particularly seen in winter. Discomfort such as crackling discharge noise, pain at the time of discharge, and clinging to the body is given.

It is possible to produce a fiber having both characteristics of a nylon fiber and a polyester fiber and having excellent low elastic modulus, high elastic recovery property, antistatic property, low temperature dyeability, heat setting property and light fastness. If so, the above-mentioned problem of the nylon fiber can be solved, and a fabric having a soft feeling and excellent in heat setting property and antistatic property can be manufactured, but such a fiber has not been known so far.

[0007] Fibers having good dyeing properties for disperse dyes, low elastic modulus, and excellent elastic recovery properties include, for example,
The polytrimethylene terephthalate fiber disclosed in JP-A-52-5320 is mentioned. The fiber disclosed herein has a low elastic modulus comparable to nylon and has excellent elastic recovery, but does not have antistatic properties like polyethylene terephthalate fiber.

Further, as the antistatic polyester fiber,
Polyester fiber using a block alkylene ether amide as an antistatic agent (for example, JP-B-44-16178)
JP, JP-B-46-7213, JP-A-61-2
No. 8016), a technique of dispersing a block alkylene ether amide or a block polyalkylene ether ester in a polyester (for example, Japanese Patent Publication No. 48-103)
No. 80, Japanese Unexamined Patent Publication No. 50-107206), etc., all of which have a low elastic modulus comparable to nylon.
Fibers with excellent elastic recovery cannot be obtained. Also, the dyeability at low temperatures is not sufficient.

Further, a method of copolymerizing polybutylene terephthalate or polytrimethylene terephthalate with polyoxyalkylene glycol for the purpose of obtaining a polyester elastomer is already known (for example, Japanese Patent Application Laid-Open No.
No. 2-6796). However, in this invention, there is no description about a specific fiberizing method or a polymer using trimethylene glycol. Furthermore, since it is intended to be an elastomer, the molecular weight, copolymerization ratio, and form of the polyalkylene glycol are not appropriate and exhibit little antistatic properties. In addition, even if it is made into a fiber, it has strength, light fastness, and dry cleaning fastness. Or the spinnability is not sufficient and the yield is reduced, and the application is remarkably limited because it is difficult to make fine denier.

As described above, in the range of the prior art, low elastic modulus, high elastic recovery property, antistatic property, low-temperature dyeability, heat setting property having both characteristics of nylon fiber and polyester fiber. There is no known fiber having excellent light resistance.

[0011]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a low elastic modulus, a high elastic recovery property, an antistatic property, a low temperature dyeability, and a heat setting property, which have both characteristics of a nylon fiber and a polyester fiber. Another object of the present invention is to provide a fiber having excellent light resistance. More specifically, it can be dyed at a temperature of 110 ° C. or less with respect to a disperse dye, and has an elastic recovery rate of 7% at 20% elongation.
In an effort to provide a polyester-based composite fiber useful for obtaining a soft-textured woven or knitted fabric having 0% or more, an elastic modulus of 40 g / d or less, good heat setting properties and antistatic properties. is there.

[0012]

Means for Solving the Problems As a result of diligent studies, the present inventors have used a polyester polymer having terephthalic acid as a main acid component and trimethylene glycol as a main glycol component, and further forming a fiber structure. At the stage, it was found that the fiber in which the antistatic agent was introduced into the core could solve the above-mentioned problem, and as a result of further study, the present invention was reached.

That is, the present invention relates to a polyester composite fiber comprising a sheath and a core, wherein the sheath comprises a polyester comprising terephthalic acid as an acid component and trimethylene glycol as a glycol component, and the core comprises terephthalic acid. An antistatic agent comprising a polyester copolymer obtained by copolymerizing 10 to 80% by weight of a polyethylene glycol having an average molecular weight of 4000 to 20,000 as a third component with a polyester having a glycol component of trimethylene glycol or ethylene glycol as an acid component. Or a polyester polymer having a fiber-forming ability in which the antistatic agent is dispersed, wherein the ratio of the antistatic agent to the entire fiber is 0.1 to 10% by weight, and the peak temperature of the loss tangent is satisfied. Is 85
C. to 115 ° C. and the modulus of elasticity Q (g / g
a polyester-based composite fiber, wherein the relationship between d) and the elastic recovery rate R (%) satisfies the following expression (1): 0.18 ≦ Q / R ≦ 0.35 (1)
It is.

In the polyester-based conjugate fiber of the present invention, the polymer constituting the sheath portion is a polyester containing terephthalic acid as an acid component and trimethylene glycol as a glycol component, and is required as long as the effects of the present invention are not impaired. Depending on the above, other components described later may be copolymerized. The polymer constituting the core portion is a polyester having terephthalic acid as an acid component and trimethylene glycol or ethylene glycol as a glycol component, and a third component is polyethylene glycol having an average molecular weight of 4000 to 20,000 in an amount of 10 to 80% by weight. An antistatic agent consisting of a polymerized polyester copolymer, or a polyester polymer having a fiber-forming ability in which the antistatic agent is dispersed, as long as the effects of the present invention are not impaired, if necessary,
Other components described later may be copolymerized. This core is extremely important in exhibiting antistatic properties.

The trimethylene glycol used in the present invention may be any of 1,3-propanediol, 1,2-propanediol, 1,1-propanediol, 2,2-propanediol, and a mixture thereof. From the viewpoints of elastic recovery, heat setting, and thermal stability,
3-propanediol is particularly preferred. The antistatic agent is a polyester having terephthalic acid as an acid component and trimethylene glycol or ethylene glycol as a glycol component, and a third component having an average molecular weight of 4,000 to 20,000.
Is a polyester copolymer in which 10 to 80% by weight of polyethylene glycol is copolymerized. Average molecular weight 400
When it is less than 0, the antistatic effect is small and the average molecular weight is 2
When it is larger than 0000, the thermal stability of the antistatic agent becomes poor, and the spinning stability becomes poor. The copolymerization ratio is 10 to 80% by weight. When the copolymerization ratio is less than 10% by weight, the antistatic effect is small. When the copolymerization ratio is more than 80% by weight, the thermal stability of the antistatic agent is deteriorated. Stability is poor. The preferred average molecular weight and copolymerization ratio are determined based on the balance between antistatic effect and thermal stability. The average molecular weight is 5,000 to 10,000, and the copolymerization ratio is preferably from 5 to 35% by weight.

Further, from the viewpoint of enhancing antistatic properties and spinnability,
5-sodium sulfoisophthalic acid, 5-potassium sulfoisophthalic acid, 5-lithium sulfoisophthalic acid, 3
It is very preferable to further copolymerize a metal sulfophthalic acid such as sodium sulfoterephthalic acid, and the copolymerization ratio is 0.5 to 3% by weight, particularly preferably
0.7 to 1.5% by weight. For the same reason, 0.1 to 5% by weight of an antistatic aid composed of a known nonionic or ionic surfactant, sodium alkylbenzenesulfonate, sodium bromide, potassium bromide or the like is contained. You may.

The core is made of only the antistatic agent specified in the present invention,
Alternatively, the antistatic agent is dispersed in a polyester capable of forming a fiber. Here, the polyester having a fiber-forming ability is polyester, polyethylene terephthalate, polyethylene isophthalate, polybutylene terephthalate, or a copolymerized polyester in which these are the main components used in the sheath of the present invention.

As described above, the polyester-based conjugate fiber of the present invention may contain isophthalic acid, succinic acid, or the like in any of the polymer in the sheath portion and the core portion, as long as the effects of the present invention are not impaired. Acid components such as adipic acid and 2,6-naphthalenedicarboxylic acid, and 1,4-butanediol,
A glycol component such as 1,6-hexanediol, ε-caprolactone, 4-hydroxybenzoic acid and the like may be copolymerized. The copolymerization ratio is preferably within 10% by weight, more preferably within 5% by weight. However, in this case, it is necessary that the copolymer component is such that the deterioration of the fastness does not occur.

Further, if necessary, various additives such as a matting agent, a heat stabilizer, an antifoaming agent, a tinting agent, a flame retardant, an antistatic agent, an antioxidant, an ultraviolet absorber, and an infrared ray An absorber, a crystal nucleating agent, a fluorescent whitening agent and the like may be copolymerized or mixed as necessary. The polyester polymer and the antistatic agent of the sheath and the core constituting the polyester composite fiber of the present invention can be polymerized by a known method. For example, antistatic agents are commonly used in the production process of polytrimethylene terephthalate or polyethylene terephthalate,
It can be produced by adding polyethylene glycol at a predetermined ratio to the reaction system during the transesterification reaction or the polycondensation reaction and copolymerizing. The copolymer component can be added as it is or after being dispersed, dissolved, or heat-treated in a suitable solvent such as trimethylene glycol or ethylene glycol.

In the polyester-based composite fiber of the present invention, the antistatic agent is present only in the core portion, and the antistatic agent does not mix with the polyester capable of forming fibers in the sheath portion or the core portion in the molecular order. It exhibits high antistatic properties because it exists independently with a certain size. Furthermore, light resistance, hydrolysis resistance,
Solvent resistance, antistatic agent with low washing fastness does not appear on the fiber surface, so these disadvantages do not become apparent,
High antistatic properties can be exhibited. Compared to the case where the core is only an antistatic agent, dispersing in a polyester capable of forming fibers reduces the cost of the raw yarn, and also generally improves the long-term spinning stability and increases the spinning yield. Is more preferable.

In the polyester-based composite fiber of the present invention, the form in which the antistatic agent is dispersed in the polyester capable of forming a fiber is not particularly limited.
1 and 2 are typical examples. Figure 1 is a parallel type,
Wood type, radial type, multi-core type, mosaic type, sea-island type, nebula type. FIG. 1 illustrates a case where the fiber cross section is round, but of course, it may have a different shape such as a triangle or a star. Among these structures, the structure having the highest antistatic property is preferably a structure in which the antistatic agent is dispersed in a streak shape in the yarn length direction.
The length of the streak is not particularly limited, but the longer the longer, the better the antistatic property. In general, it may be 0.01 μm or more. More preferably, as shown in FIG. 2, it has a structure in which three or more layers of a fiber-forming polyester and an antistatic agent are laminated, and has a streak-like dispersion in the yarn length direction. In this case, it is possible to exhibit high antistatic properties with the least amount of antistatic agent.

The polyester composite fiber of the present invention has an antistatic agent ratio of 0.1 to 10% by weight. When the amount is less than 0.1% by weight, sufficient antistatic property is not exhibited, and when the amount exceeds 10% by weight, spinnability and spinning yield deteriorate. Preferably, it is 1 to 7% by weight, more preferably 3 to 7% by weight. In the polyester composite fiber of the present invention, the ratio of the core portion to the whole fiber can be arbitrarily determined in consideration of the amount of the antistatic agent used. Generally, the content of the core is 0.1 to 90% by weight based on the total fibers. When the core is made of only the antistatic agent, the ratio of the core is preferably 0.1 to 10% by weight. When the antistatic agent is dispersed in the polyester having a fiber forming ability, the ratio of the core may be determined so that the ratio of the antistatic agent to the fibers is 0.1 to 10% by weight. In this case, the ratio occupied by the core is 20 to 90% by weight.
Is preferred.

The polyester conjugate fiber of the present invention needs to have a peak temperature of a loss tangent (hereinafter abbreviated as Tmax) of 85 to 115 ° C. determined from dynamic viscoelasticity measurement. This is because in this range, the disperse dye required by the present invention at 110 ° C. and the fastness can be secured. Since Tmax corresponds to the molecular density of the amorphous part,
The smaller this value is, the smaller the molecular density of the amorphous portion is, so that the void portion for the dye is large, the dye is easy to enter, and the exhaustion rate is high. Tmax is 85
If the temperature is lower than ℃, the molecules tend to move at a low temperature, so that the physical properties and texture are changed or dyed in the usual post-processing such as heat setting, and the stage of normal use such as ironing. The dry cleaning fastness of the subsequent fabric will be deteriorated. Tmax is 115 ° C
If it exceeds 10, the dyeability, which is the object of the present invention, decreases, and 11
At 0 ° C. or lower, it becomes impossible to dye to a deep color with a disperse dye.

As described above, since Tmax is a structural factor of a fiber, even if the polymers have the same copolymer composition, they exhibit different values depending on spinning conditions such as spinning temperature, spinning speed, draw ratio, and heat treatment temperature. Things. Since the rate of change of Tmax when these conditions are changed differs for each copolymer composition, it is necessary to study while examining the relationship between the conditions and Tmax. 115 ° C. in the case of the present invention
If it exceeds, the effect of improving the dyeability is small and the dyeability at 110 ° C is not exhibited. However, this is not necessarily the case as low as possible, and the amorphous portion becomes too coarse, so that it has a drawback that the dye can easily enter and at the same time easily escape. That is, the fastness, especially the fastness to dry cleaning, the fastness to wet friction, the fastness to washing, and the like are reduced. In addition, problems such as deterioration of texture due to curing during heat setting and decrease in dimensional stability arise.

The polyester composite fiber of the present invention has an elastic modulus Q (g / d) and an elastic recovery rate R (%) after elongation of 20% and standing for 1 minute after satisfying the formula (1). is necessary. 0.18 ≦ Q / R ≦ 0.35 (1) If Q / R> 0.35, the elasticity is too high, so that a soft feel comparable to nylon aimed at in the present invention cannot be obtained. Alternatively, the elastic recovery properties are insufficient, and the fibers once deformed by the application of stress cannot return to the original state, and only a fabric having poor form stability can be obtained. vice versa,
Since there is substantially no region where Q / R <0.18, the lower limit of Q / R is set to 0.18 in the present invention. The specific elastic modulus that can be in the range of the formula (1) is usually 20 to 40 g / d, and the elastic recovery is 70 to 99%.

The polyester composite fiber of the present invention can be obtained by the following method. When spinning from the spout pack during spinning, two types of polyester, a fiber-forming polyester polymer and an antistatic agent, are used, so it is necessary to select a spout pack suitable for producing a desired cross-sectional structure. However, known techniques can be used for these. Hereinafter, an example of a spinning pack is shown with a schematic diagram.

When the core is composed of only an antistatic agent,
For example, a spinning pack as shown in FIG. 3 may be used. In FIG. 3, after the fiber-forming polyester polymer has passed through the filtration section from A and the antistatic agent has passed through the filtration section from B, it is introduced into the capillary 2 through the horizontal flow path 1 and is discharged from the spinneret 3 to form a filament group. By the discharge molding, the structure comprising the sheath and the core, which is the object of the present invention, can be obtained. When a mixture of an antistatic agent and a fiber-forming polyester is supplied from B, it is also possible to produce a fiber in which the antistatic agent is dispersed in the lengthwise direction of the yarn. Further, when the antistatic agent is present in the form of a streak dispersed in the yarn length direction, and in the case of producing a fiber having a structure in which three or more layers of the fiber-forming polyester and the antistatic agent are laminated in the cross-sectional structure, for example, A spinning pack as shown in FIG. 4 may be used. That is, a polyester having a fiber forming ability and an antistatic agent are separately introduced from C and D, and after passing through the respective filtration sections, they are kneaded by the static kneading element 4. By this static kneading element, the polyester capable of forming fibers and the antistatic agent are separated into three or more layers.
After being laminated in multiple layers by the static kneading element 1, it enters the capillary 2 through the horizontal flow path 1, flows out of the spinneret 3 and is discharged and formed as a filament group.

As the static kneading element used for spinning, for example, a known mixer such as a static mixer manufactured by Kenix Co., Ltd., a mixing unit manufactured by Toray Engineering Co., Ltd., and a mixing element manufactured by Sluzer Co., Ltd. are used.
The number of layers is determined by the number of static kneading elements, but is usually 2 or more, preferably 4 to 16 layers. The polyester-based composite fiber of the present invention can be obtained by extruding from a spinneret, winding it up, and then drawing it. Here, performing stretching after winding means that after spinning, winding is performed on a bobbin or the like, and the yarn is stretched using another device. After cooling and solidifying, it is wrapped several times around the first roll rotating at a constant speed, so that the tension before and after the roll is not transmitted at all, and installed next to the first roll and the first roll It refers to a so-called straight drawing method in which a spinning-drawing process is directly connected, such as drawing with a certain second roll.

In the present invention, the spinning temperature at the time of spinning the polymer is preferably from 240 to 340 ° C., more preferably from 245 to 320 ° C., and particularly preferably from 250 to 3 ° C.
A range of 00 ° C is appropriate. If the spinning temperature is lower than 240 ° C., the temperature is too low and it is difficult to obtain a stable molten state, the resulting fibers have large irregularities, and do not exhibit satisfactory strength and elongation. On the other hand, when the spinning temperature exceeds 340 ° C., the thermal decomposition becomes severe, and the obtained yarn is colored and does not show satisfactory strength and elongation.

The winding speed of the yarn is not particularly limited, but is usually preferably 3500 m / min or less, more preferably 2500 m / min or less, and particularly preferably 20 m / min or less.
Wind up at less than 00m / min. Winding speed 3500m /
If it exceeds min, crystallization proceeds too much before winding, and the molecules cannot be oriented because the stretching ratio cannot be increased in the stretching step, and sufficient yarn strength and elastic recovery cannot be obtained. And the bobbin and the like cannot be pulled out of the winding machine.

The stretching ratio at the time of stretching is preferably from 2 to 4 times, more preferably from 2.2 to 3.7 times, particularly preferably from 2.5 to 3.5 times. If the draw ratio is 2 or less, the polymer cannot be sufficiently oriented by drawing, and the elastic recovery of the obtained yarn will be low, and the formula (1) cannot be satisfied. On the other hand, if it is four times or more, thread breakage is severe and stretching cannot be performed stably.

The temperature at the time of stretching is from 35 to 35 in the stretching zone.
75 ° C is preferred, more preferably 40 to 70 ° C, particularly preferably 45 to 65 ° C. If the temperature of the drawing zone is lower than 35 ° C., yarn breakage occurs frequently during drawing, and fibers cannot be obtained continuously. On the other hand, when the temperature exceeds 80 ° C., the slipperiness of the fiber with respect to a heating zone such as a drawing roll deteriorates, so that single yarn breakage occurs frequently and the yarn becomes full of fluff. In addition, since the polymers slip through each other, sufficient orientation is not applied, and the elastic recovery rate decreases.

The polyester composite fiber of the present invention is preferably subjected to a heat treatment after drawing. This heat treatment is preferably performed at 90 to 200 ° C., more preferably 100 to 200 ° C.
To 190 ° C, particularly preferably 110 to 180 ° C.
If the heat treatment temperature is lower than 90 ° C., the crystallization of the fiber does not sufficiently occur, and the elastic recovery is deteriorated. At a temperature higher than 200 ° C., the fibers are cut in the heat treatment zone and cannot be drawn.

The polyester-based conjugate fiber of the present invention comprises 11
The K / S, which is the deep chromaticity when dyed at 0 ° C., is preferably 20 or more. Since K / S when dyeing ordinary polyethylene terephthalate fiber at 130 ° C. is about 20, it is considered that if K / S is 20 or more, color development equivalent to ordinary polyethylene terephthalate fiber is developed. Can be. Also, since the dye used for evaluating the dyeability has a large molecular structure, using this dye,
As long as a high dyeing property is obtained, a high dyeing property with a K / S of 20 or more can be ensured regardless of the type of disperse dye used.

In order for the dyed material thus dyed to exhibit high fastness, it is desirable that the fastness to dry cleaning is 3 or higher. The dry cleaning fastness in the present invention is an evaluation of liquid contamination. The evaluation items of the fastness include water fastness, washing fastness, sublimation fastness, friction fastness, and the like, but according to the study of the present inventors, the fastness of dry cleaning is 3 or more. For example, in the polyester-based conjugate fiber of the present invention, it has been found that all of the remaining fastnesses except for the light fastness are at a level that is industrially acceptable. Accordingly, the fastness to dry cleaning is an index indicating the overall fastness to dyeing of the polyester composite fiber of the present invention.

In order to use the polyester-based composite fiber of the present invention in outer clothing, it is preferable that the dyeing condition of the present invention be 3-4 or higher, more preferably 4 or higher. It is desirable to show In the polyester-based conjugate fiber of the present invention, the necessary antistatic property to be achieved can be known from the friction voltage and the half-life. The smaller the value of the friction band voltage required for use in clothing, the better, but generally it is preferably 2000 V or less, more preferably 1500 V or less.
Also, the half-life is better if the value is smaller,
Generally, it is preferably 20 seconds or less, and more preferably 1 second or less.
5 seconds or less.

[0037]

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

[0038]

(Equation 1)

Ηr in the definition formula is a value obtained by dividing the viscosity at 35 ° C. of a diluted solution of the polyester polymer dissolved in o-chlorophenol having a purity of 98% or more by the viscosity of the solvent itself measured at the same temperature. It is defined as relative viscosity. C is the solute weight value in grams in 100 ml of the solution. (2) Loss tangent Using Orientec Co., Ltd.'s Leo Vibron, in dry air, at a measurement frequency of 110 Hz, at a heating rate of 5 ° C./min.
The loss tangent (tan δ) at each temperature and the dynamic elastic modulus were measured. From the result, a loss tangent-temperature curve was obtained, and the peak temperature of the loss tangent, Tmax, was determined on this curve.
(° C.). Heating rate 5 ° C / min, measurement frequency 1
It was determined at 10 Hz. (3) Dyeability {Evaluation Exhaustion Rate, Deep Chromaticity (K / S)} A sample is made of a single-piece knitted fabric of polyester-based composite fiber, and hot water containing score roll 400 at 2 g / liter is used.
After scouring at 70 ° C. for 20 minutes, drying with a tumbler drier, and then using a pin tenter at 180 ° C. for 30 minutes.
The heat set of second was used. The exhaustion rate is 40
After the temperature was raised from 110 ° C. to 110 ° C., the temperature was further maintained for 1 hour, and then evaluated by the exhaustion rate. The dye used was Kayaron Polyester Blue 3RSF (manufactured by Nippon Kayaku Co., Ltd.), and was 6% o.
Wf, dyeing at a bath ratio of 1:50. As a dispersant, 0.5 g / l of Nikka Sun Salt 7000 (manufactured by Nika Chemical Co., Ltd.) was used, and the pH was adjusted to 5 by adding 0.25 ml / l of acetic acid and 1 g / l of sodium acetate.

The exhaustion rate was obtained by measuring the absorbance A of the stock dye solution and the absorbance a of the dye solution after dyeing using a spectrophotometer and substituting them into the following equation. The absorbance is 5 which is the maximum absorption wavelength of the dye.
The value at 80 nm was adopted. Exhaustion rate = (A−a) / A × 100 (%) The deep chromaticity, which indicates how deeply colored, was evaluated using K / S. This value is obtained by measuring the spectral reflectance R of the sample cloth after dyeing, and calculating the following Kubelka-Munk (Kub).
elka-Munk). The larger the value, the greater the deep color effect, that is, the better the color development. As R, the value at the maximum absorption wavelength of the dye was used.

K / S = (1-R) ² / 2R (4) Color fastness Evaluation was made using 500 mg of a single-mouth knitted fabric dyed by the method of the above (3). The dry cleaning fastness (DC fastness) is JIS-L-0860, and the light fastness is JIS.
-L-0842, washing fastness according to JIS-L-0844
The dry / wet friction fastness was measured in accordance with JIS-L-0849. (5) Elastic recovery rate The elastic recovery was determined as an elastic recovery rate obtained by the following method.

The fiber was attached to a tensile tester with a distance between chucks of 20 cm, and a stretching speed of 20% was applied to an elongation of 20%.
Extend at cm / min and leave for 1 minute. Thereafter, it is returned to the original length (X) at the same speed again, and at this time, the moving distance of the chuck under the stress (residual elongation:
X ′) was read and determined according to the following equation. Elastic recovery rate = (XX ′) × 100 / X (6) Antistatic property (frictional band voltage, half-life) The frictional band voltage is JIS-L-1094 B method, and the half-life is JIS-L- Method 10A was followed.

[0043]

Example 1 1,3-propanediol (hereinafter referred to as TM
G) (abbreviated as G), 1,300 parts by weight of dimethyl terephthalate (hereinafter abbreviated as DMT), and 1.3 parts by weight of titanium tetrabutoxide as a transesterification catalyst. .
Subsequently, titanium tetrabutoxide 1.3 was used as a polycondensation catalyst.
A weight part was added and polycondensation was performed at 260 ° C. at a reduced pressure of 0.5 torr to obtain a fiber-forming polyester polymer.
The intrinsic viscosity of the obtained polymer was 0.62.

On the other hand, ethylene glycol (hereinafter referred to as EG,
The transesterification reaction was carried out at 220 ° C. using 915 parts by weight of DMT, 1,300 parts by weight of DMT, and 0.65 parts by weight of manganese acetate as a transesterification catalyst. Next, polyethylene glycol having an average molecular weight of 6000 (hereinafter referred to as P
EG6000) (321 parts by weight), 0.65 parts by weight of antimony trioxide as a polycondensation catalyst, and 0.39 parts by weight of trimethylphosphite as a stabilizer.
Polycondensation is performed at 85 ° C at a reduced pressure of 0.5 torr, and PE
A polymer used as an antistatic agent was obtained by copolymerizing G6000 at 25% by weight.

The obtained two types of polymer chips were dried at 130 ° C. for 20 hours under a nitrogen stream of 100 ml / min. Then, using the spinning pack shown in FIG.
And an antistatic agent from B through a gear pump, and spun at a spinning speed of 1200 m / min using 36 single-array spinnerets to produce an undrawn yarn. Next, the obtained undrawn yarn is subjected to a hot roll at 50 ° C., a hot plate at 140 ° C., and a draw ratio of 3.0.
Twisting was performed at a drawing speed of 600 m / min to obtain a drawn yarn of 50 denier / 36 filaments. The ratio of the core of the obtained fiber (the ratio of the antistatic agent) was 5% by weight. The physical properties of the fiber were 3.2 g / d in strength, 37% in elongation, 23 g / d in elastic modulus, and 91% in elastic recovery. Also, Q /
R was 0.25, thereby satisfying the expression (1).

Q / R = 0.25 <0.35 The dyeability of the polyester composite fiber of the present invention is determined by comparing the dyeability of a polyethylene terephthalate fiber spun by a conventional method with a blue disperse dye at 130 ° C. for 60 minutes. It can be evaluated by comparing. When dyed with Kayaron Polyester Blue 3RSF (manufactured by Nippon Kayaku Co., Ltd.) as a dye at 6% owf and a bath ratio of 1:50, the exhaustion rate of polyethylene terephthalate fiber by a conventional method at 130 ° C. for 60 minutes was determined 93%, the K / S of the obtained dyed product was 21.4. 1 of the polyester-based composite fiber obtained in this example
The exhaustion rate at 10 ° C. for 60 minutes was 93%, and the K / S of the obtained dyed product was 22.3. The results show that the dyeability of the polyester-based conjugate fiber of the present invention at 110 ° C. for 60 minutes is equivalent to the dyeability of polyethylene terephthalate fiber according to the conventional method at 130 ° C. for 60 minutes.

No color fading was observed in the dry cleaning fastness of the one-necked knitted fabric after dyeing, and the liquid contamination was grade 4-5. In addition, light fastness (grade 3-4), dry / wet friction fastness (grade 5), and wash fastness (grade 5) were also good. The friction band voltage was 1400 V, and the half-life was 7 seconds, which was good.

[0048]

Examples 2 to 4 In the same manner as in Example 1 except that polyethylene glycol having an average molecular weight of 20,000 (hereinafter abbreviated as PEG 20,000) was used (Example 4). Polymerization and spinning experiments were carried out by varying the copolymer composition and the weight ratio (%) to the whole (Examples 2, 3). Table 1 summarizes the results. All of the polyester-based composite fibers satisfied the formula (1) and exhibited good dyeing properties, fastness, antistatic properties and various physical properties.

[0049]

[Comparative Example 1] PEG1000 instead of PEG6000
Polymerization and spinning were carried out in the same manner as in Example 1 except for using, to obtain a fiber. The obtained fiber had a frictional voltage of 3400 V, which was lower than the frictional voltage of polyethylene terephthalate, but was practically non-static. Table 1 shows the results.

[0050]

[Table 1]

[0051]

Comparative Example 2 Polyester made of TMG and DMT
EG6000 was spun alone with 5% by weight of a copolyester in the same manner as in Example 1 to prepare a fiber having a round cross-section and a uniform structure. When this fiber was dyed at 110 ° C., the exhaustion rate was 99% and K / S was 23.5. However, the fastness to dry cleaning was 1st or 2nd grade, and the fastness to light was 2nd or 3rd grade.

[0052]

Comparative Example 3 Polymerization and spinning were carried out in the same manner as in Example 1 except that the ratio of the core portion (the ratio of the antistatic agent) was changed to 20%. However, yarn breakage and fluffing occurred during spinning, and good fibers could not be obtained.

[0053]

Example 5 The same fiber-forming polyester polymer as in Example 1 and 30% by weight of PEG 6000 among the antistatic agents of Example 1 and 1% by weight of 5-sodium sulfoneisophthalic acid were copolymerized. The mixture was chip-blended after drying, and the blend of the fiber-forming polymer from A and the blend of the fiber-forming polymer and the antistatic agent from B was minimized using the spinning pack shown in FIG. The mixture was passed through a gear pump, extruded using 36 single-array spinnerets, and spun in the same manner as in Example 1 to obtain an undrawn yarn. At this time, the flow rate of the gear pump and the chip blend ratio were adjusted so that the amount of the antistatic agent was 5% by weight with respect to the fiber. This undrawn yarn is hot rolled at 55 ° C., hot plate at 140 ° C., drawn at a draw ratio of 3.1 times, drawn at a drawing speed of 600
Stretching was performed at m / min to obtain a drawn yarn of 50 denier / 36 filaments.

When the cross section of the obtained fiber was observed under a microscope, the core was a sea-island type in FIG. 1 (the antistatic agent was an island). When the fiber was cut in the yarn length direction and the cut surface was observed, the antistatic agent was dispersed in a streak shape. When the obtained fiber was dyed at 110 ° C., the exhaustion rate was 97% and the K / S was 23.1. In addition, both the fastness to dry cleaning and the fastness to light were grade 4. The friction band voltage is 120
0V and a good half life of 6.3 seconds.

[0055]

Example 6 The same fiber-forming polyester polymer as in Example 1 was obtained from C using the spinning pack shown in FIG.
From D, the antistatic agent obtained by copolymerizing 25% by weight of PEG 6000 of Example 1 was flown using a gear pump, extruded using 36 single-array spinnerets, spun in the same manner as in Example 1, and undrawn. Yarn was obtained. Eight static kneading elements were used, and the amount of the gear pump was adjusted so that the amount of the antistatic agent was 3 to the fiber.
% By weight. This undrawn yarn is hot rolled at 55 ° C., hot plate at 140 ° C., drawn at a draw ratio of 3.1 times,
Stretching was performed at a drawing speed of 600 m / min to obtain a drawn yarn of 50 denier / 36 filaments.

When the cross section of the obtained fiber was observed under a microscope, at least six layers of the core were confirmed as shown in FIG. When the fiber was cut in the yarn length direction and the cut surface was observed, the antistatic agent was dispersed in a streak shape. When the obtained fiber was dyed at 110 ° C., the exhaustion rate was 97%,
K / S was 21.9. In addition, both the fastness to dry cleaning and the fastness to light were grade 4. The friction band voltage was 1700 V, and the half-life was 17 seconds, which was good.

As can be understood from comparison with Example 2, when the antistatic agent is dispersed in the form of a layer and streaks in the yarn length direction, the antistatic agent has the same antistatic properties as the case where the core is made of only the antistatic agent, and the antistatic agent is less. Can be achieved in quantity.

[0058]

Comparative Example 4 Polymerization and spinning were carried out in the same manner as in Example 1 except that the temperature of the hot roll was changed to 30 ° C. However, many yarn breaks occurred during drawing, and continuous fibers could not be obtained.

[0059]

Comparative Example 5 Polymerization and spinning were carried out in the same manner as in Example 1 except that the temperature of the hot roll was changed to 80 ° C. However, since the yarn was fused to the hot roll during stretching, single yarn breakage occurred frequently, and the resulting fiber was full of fluff.

[0060]

Comparative Example 6 Polymerization and spinning were carried out in the same manner as in Example 1 except that the temperature of the hot plate was changed to 80 ° C. Fibers were obtained without problems such as yarn breakage and fluff. However, the obtained fiber has a low elastic recovery of 60%, and
R was 0.38, which was not able to satisfy the expression (1).

[0061]

Comparative Example 7 Polymerization and spinning were carried out in the same manner as in Example 1 except that the temperature of the hot plate was set to 200 ° C. The fibers broke at the hot plate and could not be stretched.

[0062]

Comparative Example 8 Polymerization and spinning were carried out in the same manner as in Example 1 except that the draw ratio was 2.3 times and the temperature of the hot plate was 180 ° C. Fibers were obtained without problems such as generation of fluff. However, the obtained fiber had a low elastic recovery rate of 57%, which resulted in a Q / R of 0.51 and could not satisfy the expression (1).

[0063]

The polyester composite fiber of the present invention can be dyed at a temperature of 110 ° C. or less with respect to a disperse dye.
The elastic recovery at the time of elongation is 70% or more, and the elastic modulus is 40 g /
When d or less, the fiber has good heat setting properties and high antistatic properties. Therefore, it can be mixed with fibers that are difficult to dye at the dyeing temperature of ordinary polyethylene terephthalate-based fibers, and can exhibit a soft texture. Furthermore, since it has high antistatic properties, even when the mixing ratio of the polyester-based composite fiber of the present invention is high, it does not cause problems such as clinging due to static electricity and discharge.

The polyester-based composite fiber of the present invention makes use of the above-mentioned advantages and can be used from low to high applications.
In addition to being capable of being mixed with cellulose fibers, it is particularly useful for mixing fibers having low heat resistance such as natural fibers such as silk and wool, polyamide fibers and polyurethane fibers. Of course,
Advanced functions can be achieved even when used alone.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view schematically showing a dispersion example of an antistatic agent in a core portion of a polyester-based conjugate fiber of the present invention.

FIG. 2 is a cross-sectional view schematically showing a preferred dispersion example of an antistatic agent in a core portion of the polyester-based conjugate fiber of the present invention.

FIG. 3 is a cross-sectional view schematically showing an example of a spinning pack used when producing the polyester-based composite fiber of the present invention.

FIG. 4 is a cross-sectional view schematically showing an example of a spinning pack used for manufacturing a polyester-based composite fiber of the present invention in which at least three layers of a fiber-forming polyester and an antistatic agent are laminated in a core portion. .

[Explanation of symbols]

 A: Sheath part B: Core part AD: Polymer inlet 1: Horizontal flow path 2: Capillary 3: Spindle 4: Static kneading element

Claims (3)

[Claims] 1. A polyester composite fiber comprising a sheath and a core, wherein the sheath comprises a polyester comprising terephthalic acid as an acid component and trimethylene glycol as a glycol component, and the core comprises terephthalic acid as an acid component. An antistatic agent comprising a polyester copolymer obtained by copolymerizing 10-80% by weight of polyethylene glycol having an average molecular weight of 4,000 to 20,000 as a third component with a polyester having trimethylene glycol or ethylene glycol as a glycol component, or It is made of a polyester polymer having a fiber-forming ability in which the electric agent is dispersed, and satisfies that the ratio of the antistatic agent to the entire fiber is 0.1 to 10% by weight, and the peak temperature of the loss tangent is from 85 ° C. 115 ° C. and the elastic modulus Q (g / d) and elastic recovery rate R of the fiber
(1) A polyester-based composite fiber characterized by satisfying the following expression (1): 0.18 ≦ Q / R ≦ 0.35 (1) 2. The polyester-based conjugate fiber according to claim 1, wherein the antistatic agent is present in a streak-like dispersion in the yarn length direction. 3. The polyester conjugate fiber according to claim 1, wherein in the cross section of the conjugate fiber, the core has a structure in which three or more layers of a fiber-forming polyester polymer and an antistatic agent are laminated.