JP5718045B2 - Polyester fibers and fiber aggregates with excellent dyeability - Google Patents

Description

  The present invention forms a fabric that has a good texture with sublimeness, bulge, tension and waist, and is light and opaque, and has high color and fastness even in dyeing under normal pressure environment. Provided are fibers and fiber assemblies having very good properties.

  Polyester fibers are used in various fields mainly for apparel because of their mechanical properties, coloring properties, and handling properties. However, in general, polyester fibers are inferior in dyeability due to their dense fiber structure. Particularly when disperse dyes are used, good color developability can be obtained at a high temperature and high pressure of 130 ° C. or when a carrier agent in an organic solvent is not used. It is difficult to obtain robustness.

  On the other hand, there is a need for technology to produce polyester mixed products that have good dyeing characteristics without complicated processes, by knitting and weaving polyester fibers with materials other than polyester, such as wool, cotton, acrylic, and polyurethane. However, in this case, in order to impart sufficient dyeing characteristics to the polyester fiber, it is necessary to carry out a dyeing process under a high temperature and high pressure of around 130 ° C. However, since the material knitted and woven with the polyester fiber deteriorates in that environment, for example, under the normal pressure environment, more specifically, the expression of the polyester fiber having good dyeing characteristics even at 100 ° C. or less. It has been needed.

  For this reason, many methods for improving the dyeability by modifying the polyester resin have been studied so far. Among them, a sulfonic acid metal base is copolymerized as a dicarboxylic acid component to form a cationic dye and a disperse dye at normal pressure. Many inventions that can produce easily dyeable polyester fibers have been proposed (see Patent Documents 1 to 3). Commonly used as the sulfonic acid metal base is 5-sodium sulfoisophthalic acid or 5-potassium sulfoisophthalic acid component, and the conventional polyester is obtained by copolymerizing them and then fiberizing them. Compared to fibers, it is possible to have amorphous parts in the fiber internal structure, and as a result, it is said that polyester fibers that can be dyed at normal pressure with disperse dyes and cationic dyes and have excellent fastness can be obtained. ing. However, fibers obtained by copolymerization of these sulfonic acid metal base components are likely to have lower strength than conventional polyester fibers, and are inferior in high-speed spinnability in the spinning process. Furthermore, there are disadvantages that the alkali weight reduction rate is fast, and depending on the yarn form of the spinning yarn, cracks are generated on the fiber surface in the woven or knitted fabric subjected to the alkali weight reduction, and quality defects such as powder fall are likely to occur. For this reason, even when using a single thread, it is difficult to reduce the amount of alkali, so that not only a woven or knitted fabric with a good texture cannot be obtained, but also the processing conditions are great in blending with cotton for mercerizing. You will be restricted.

JP-A-6-184820 JP 2000-355831 A JP 2003-301328 A

  Furthermore, as a trend of needs for clothing, demand for the material is increasing for tennis wear used in sports for leisure, swimwear, and white clothing used in the medical field. Synthetic fibers such as polyester and polyamide have a cold feeling like plastic because they have a large single yarn fineness, a simple cross-sectional shape, and a uniform and simple internal structure on the surface. There was a problem that it was easy to see through.

  Therefore, in order to improve the disadvantages of the synthetic fiber as described above, a core-sheath type composite fiber in which inorganic fine particles having a high refractive index are contained only in the sheath part, or the cross section of the synthetic fiber is modified, Hollowing is widely performed. However, it has been difficult to obtain a fiber assembly that exhibits opacity even when wet with water or sweat, and has performance such as lightness and sublimation.

  When the inorganic fine particles having a high refractive index are contained at a high concentration in the sheath portion of the core-sheath type composite fiber, the color tone of the composite fiber becomes strong yellow and the use is limited. Also, in the case of a hollow and round cross section, the opacity is improved due to the difference in refractive index due to the air layer, but problems such as hollow parts due to post-processing such as twisted yarn, collapse of the fiber cross section occur, and the feeling of swelling and the like Is insufficient.

  As described above, there is no conventional fiber product which is a polyester fiber having good dyeing characteristics even at 100 ° C. or less in a disperse dye and excellent in texture such as swelling.

  The present invention solves such problems in the prior art. Specifically, the present invention exhibits a deep color with respect to a disperse dye under an atmospheric pressure environment, is excellent in washing fastness and light fastness, and is always used. It is possible to ensure good dyeability and yarn quality even for mixed fibers with materials other than polyester fibers that require pressure dyeing, and to reduce the subsequent yarn quality even when alkali weight loss treatment is performed. Weaving polyester fiber that can ensure good spinnability, excellent anti-slipping properties, sublimation, swelling, tension, waist, good texture, light weight and opacity The purpose is to provide knitting.

That is, the present invention is a fiber made of a polyester resin, the cross-sectional shape is a multilobal fiber, the polyester resin is a copolymer comprising a dicarboxylic acid component and a glycol component,
A least 80 mol% terephthalic acid component and / or an ester-forming derivative of the dicarboxylic acid component, and 4.0 to 12.0 mol% in cyclohexane dicarboxylic acid component and / or an ester-forming derivative thereof And 2.0 to 8.0 mol% is an adipic acid component and / or an ester-forming derivative thereof, and the glycol component is mainly composed of an ethylene glycol component and / or an ester-forming derivative thereof. The polyester fiber is characterized by having 3 to 10 leaves and preferably 0.05 to 0.80 in the cross-sectional shape.
It is said polyester fiber which is the range of this.

  Furthermore, the present invention relates to a fiber assembly comprising the above-described polyester fiber, wherein the reflectance R at a wavelength of 500 nm is 85% or more and the porosity is 20 to 60%.

  The multileaf polyester fiber obtained by the present invention is extremely excellent in washing fastness and light fastness. Furthermore, it is possible to obtain polyester fibers and fiber aggregates that can retain sufficient breaking strength even after the alkali weight loss treatment, have a specific reflectance and porosity, and are suitable for clothing in general.

It is a schematic diagram which shows the cross-sectional shape of the fiber of this invention.

The best mode for carrying out the present invention will be specifically described below.
The polyester resin used in the present invention is a polyester having an ethylene terephthalate unit as a main repeating unit, and 80 mol% or more of the repeating unit is a terephthalic acid component and / or an ester-forming derivative thereof (hereinafter referred to as a terephthalic acid component). And the cyclohexanedicarboxylic acid component and / or its ester-forming derivative among the dicarboxylic acid components must be copolymerized in an amount of 4.0 to 12.0 mol%, and 5.0 to 10 It is preferable that 0.0 mol% is copolymerized. Further, it is necessary that the adipic acid component and / or the ester-forming derivative thereof is copolymerized in an amount of 2.0 to 8.0 mol%, preferably 3.0 to 6.0 mol%. .

  A cyclohexanedicarboxylic acid component or an ester-forming derivative thereof (hereinafter sometimes referred to as a cyclohexanedicarboxylic acid component) and an adipic acid component or an ester-forming derivative thereof (hereinafter also referred to as an adipic acid component) may be used together with polyethylene terephthalate. When polymerized, since the disorder of the crystal structure is small as compared with other aliphatic dicarboxylic acids, a fiber excellent in light fastness can be obtained while ensuring a high dyeing rate.

  By copolymerizing the cyclohexanedicarboxylic acid component, the crystal structure of the polyester fiber is disturbed, and the orientation of the amorphous part is lowered. Therefore, it becomes easy for the disperse dye to penetrate into the fiber, and the atmospheric dyeability of the disperse dye can be improved. Furthermore, since the cyclohexane dicarboxylic acid component is less disturbed in crystal structure than other aliphatic dicarboxylic acids, it is excellent in light fastness.

  If the copolymerization amount of the cyclohexanedicarboxylic acid component is less than 4.0 mol% in the dicarboxylic acid component, the degree of orientation of the amorphous part inside the fiber is high, so that the dyeability for disperse dyes under normal pressure environment is insufficient, The target dyeing rate cannot be obtained. If the dicarboxylic acid component exceeds 12.0 mol%, it is possible to ensure good quality in terms of dyeability such as dyeing rate, fastness to washing, fastness to light, etc., but spinning by a high-speed spinning method without stretching. In this case, the glass transition temperature of the resin is low and the degree of orientation of the amorphous part in the fiber is low, so that spontaneous elongation occurs during high-speed winding, and stable high-speed spinnability cannot be obtained.

  The cyclohexanedicarboxylic acid used in the present invention includes three positional isomers of 1,2-cyclohexanedicarboxylic acid, 1,3-cyclohexanedicarboxylic acid, and 1,4-cyclohexanedicarboxylic acid. From the point obtained, any positional isomer may be copolymerized, or a plurality of positional isomers may be copolymerized. Further, although there are cis / trans isomers for each positional isomer, any stereoisomer may be copolymerized, or both cis / trans positional isomers may be copolymerized. The same applies to the cyclohexanedicarboxylic acid derivative.

Like the cyclohexane dicarboxylic acid component for adipic acid component, is disturbed crystal structure of polyester fibers, since the orientation of the amorphous portion is lowered, penetrates is facilitated to the fiber inside the disperse dyes, normally disperse dyes It becomes possible to improve pressure dyeability.

  Furthermore, copolymerization of the adipic acid component with polyethylene terephthalate also has an effect on low-temperature setting properties. When the fibers obtained according to the present invention are heat-set for shape stabilization after forming the woven or knitted fabric, the heat-setting temperature is lowered. It becomes possible to do. Low-temperature setability is a desirable physical property for knit applications, and when it is combined with materials other than polyester, such as wool, cotton, acrylic, and polyurethane, the temperature required for heat setting should be kept to a level that does not degrade the properties of materials other than polyester. Is possible. In addition, even when polyester fibers are used alone, it is possible to cope with general existing knit equipment, and the use can be expected to expand.

  When the copolymerization amount of the adipic acid component in the dicarboxylic acid component is less than 2.0 mol%, the dyeability with respect to the disperse dye under a normal pressure environment is insufficient, and the desired dyeing rate cannot be obtained. In addition, when the copolymerization amount of the adipic acid component in the dicarboxylic acid component exceeds 8.0 mol%, the dyeing rate increases, but when the yarn is produced by a high speed spinning method without stretching, the inside of the fiber The degree of orientation of the amorphous part in becomes low, and spontaneous elongation during high-speed winding becomes remarkable, and stable high-speed spinnability cannot be obtained.

  In the present invention, other dicarboxylic acid components other than the terephthalic acid component, the cyclohexanedicarboxylic acid component, and the adipic acid component may be copolymerized as long as the pressure dyeability and quality of the polyester fiber are not deteriorated. . Specifically, an aromatic dicarboxylic acid component such as isophthalic acid or naphthalenedicarboxylic acid or an ester-forming derivative thereof, an aliphatic dicarboxylic acid component such as azelaic acid or sebacic acid or an ester-forming derivative thereof, alone or in a plurality of types. You may make it copolymerize in the range of a total of 10.0 mol% or less.

  However, copolymerization of these components not only makes the transesterification reaction and polycondensation reaction complicated, but if the amount of copolymerization exceeds an appropriate range, washing fastness may be reduced. Specifically, when isophthalic acid and its ester-forming derivative are copolymerized in an amount exceeding 10 mol% with respect to the dicarboxylic acid component, the fastness to washing may be deteriorated even if the constituent requirements of the present invention are satisfied. It is desirable that the amount be 5 mol% or less, more desirably 0 mol% (not copolymerize).

On the other hand, polyester fibers that are generally well-known as polyester fibers having the characteristics of normal pressure dyeable type are polyester fibers copolymerized with a sulfonic acid metal base, and in particular, 5-sodium sulfoisophthalic acid, or 5- Potassium sulfoisophthalic acid components are widely used. As a result, it is possible to retain an amorphous part in the fiber internal structure as compared with conventional polyester fibers, and as a result, polyester fibers that can be dyed at atmospheric pressure with respect to disperse dyes and cationic dyes and have excellent fastness properties. It is said that you can get. However, polyester fibers obtained by copolymerization of these sulfonic acid metal base components are likely to have lower strength than conventional ones, and are inferior in high-speed spinnability in the spinning process. Furthermore, the alkali weight reduction rate is fast, and depending on the yarn form of the spinning yarn, cracks are likely to occur on the fiber surface of the woven or knitted fabric that has been subjected to alkali weight reduction treatment, resulting in increased strength deterioration or poor quality such as powder falling. There is a fault that tends to occur. For this reason, even when using a single thread, it is difficult to reduce the amount of alkali, so that not only a woven or knitted fabric with a good texture cannot be obtained, but also the processing conditions are great in blending with cotton for mercerizing. You will be restricted. In limited applications where quality such as texture is not required, the sulfonic acid metal base may be copolymerized at a ratio of 2.0 mol% or less of the dicarboxylic acid component, but the present invention is intended. Polyester fiber that has not only excellent dyeability at normal pressure but also high strength, alkali resistance and high-speed spinnability, and metal sulfonate when used in general clothing applications that require these characteristics. The copolymerization amount of the base is preferably 1.0 mol% or less of the dicarboxylic acid component, and more preferably 0 mol% (not copolymerization).
The thickness of the fiber is preferably in the range of 0.5 to 5 dtex for clothing use, and is preferably 0.5 to 30 dtex in the industrial material field. The fibers can be used as multifilament yarns or cut and used as staple fibers. When used as multifilament yarns, the total fineness is generally 30 to 200 dtex.

  The number of leaves of the multi-leaf type polyester fiber of the present invention is preferably 3 to 10 and more preferably 3 to 5 in terms of forming deep irregularities on the fiber cross section. Moreover, it is preferable that the porosity of this multileaf type | mold polyester fiber is 20 to 60%, More preferably, it is 20 to 40%. The porosity defined in the present invention is a value calculated by optical microscope observation of the cross section of the twisted yarn measured by the method described later.

  The fiber assembly of the present invention is not limited as long as it is a woven fabric, non-woven fabric, knitted fabric, paper, or any other generally known fiber assembly, but a woven or knitted fabric is suitable for use in clothing.

  Due to the effect that the fiber cross section is a multi-leaf cross section, the void ratio between the fibers of the fiber assembly can be increased, the apparent thread diameter is increased, and the fiber assembly has a light feeling and a swelling feeling. Furthermore, the fiber aggregate is formed with a multilayered air layer, thereby increasing the reflectivity and bringing about an effect of improving opacity.

  When the porosity is less than 20%, the fiber assembly is not superior to conventional fabrics such as woven and knitted fabrics in terms of opacity, lightness, and bulkiness. On the other hand, if the porosity exceeds 60%, the fiber density is reduced although weight reduction can be expected, and the lack of see-through preventing property is insufficient in terms of swelling, tension, waist, and the like. The porosity defined in the present invention is a value measured and arithmetically operated by the method described later, and the fiber assembly of the present invention is not restricted by the specified porosity, and conforms to the intended fiber product. The porosity of a textile product (woven or knitted fabric) can be changed.

  Examples of the cross-sectional shape of the multi-leaf type polyester fiber having the above porosity include 3 to 10 leaves, preferably 3 to 5 leaves as shown in FIG. It is high and it exists in the range of 0.05-0.80 from the point which expresses the multilayering of an air layer and improves the opacity of a fiber. The degree of irregularity is a value represented by an expression described later.

  When the irregularity is less than 0.05, the unevenness of the fiber cross-sectional shape becomes small, and when the fiber assembly is made, the fiber density becomes high, so that it is difficult to make the air layer multi-layered. On the other hand, if the degree of irregularity exceeds 0.80, the unevenness of the fiber cross-sectional shape becomes large, and is easily damaged in the fiber manufacturing process, which may cause a problem of fibrillation.

  As a feature of the present invention, by using the above-described polyester resin, the retention of the deformed shape after post-processing such as dyeing is good, the porosity as a fiber assembly is high, and the opacity, lightness, and bulkiness are obtained. That is.

  In addition, the fiber assembly of the present invention has a great feature in that the reflectance R at a wavelength of 500 nm is 85% or more. When the reflectance is less than 85%, the opacity is unsatisfactory, and a white and light-colored woven or knitted fabric cannot be obtained as a fiber assembly. The reflectance R of a fiber assembly suitable as a white or light-colored woven or knitted fabric is 90% or more.

  Examples of the polyester fiber constituting such a fiber assembly having a specific reflectance as described above include a polyester fiber containing a specific amount of a white pigment. Polyester fibers can be kneaded and melted with various fine particles at the time of polymerization of polyester. By adding a white pigment having a high refractive index as fine particles, the reflectance of the fiber surface is improved and the opacity is increased. It is possible to raise. The multi-leaf type polyester fiber according to the present invention preferably contains 1 to 10% by weight, particularly 2 to 5% by weight, of a white pigment having a refractive index of 1.8 or more. When the content of the white pigment is less than 1% by weight, the aggregate composed of the fibers has a reflectance of less than 85% at a wavelength of 500 nm, and the woven or knitted fabric composed of the aggregates of the fibers that are inevitably lacked in opacity. It tends to be a thing. On the other hand, if the content of the white pigment exceeds 10% by weight, the pigment may agglomerate in the polyester fiber, which may cause fluffing and yarn breakage in the spinning / drawing process.

  In addition, it is preferable to use a white pigment having a refractive index of 1.8 or more. When the refractive index is less than 1.8, since the refractive index of the polyester fiber is 1.575 to 1.643, an improvement in the refractive index due to the addition of the white pigment cannot be expected so much, and an increase in the reflectance can be expected. Hateful. The upper limit of the refractive index of the white pigment is not particularly limited, but a white pigment having a refractive index exceeding 3 is difficult to obtain at present. Examples of such white pigments include titanium oxide, zinc oxide, lithopone, and the like. Among these, titanium oxide is preferable from the viewpoint of high refractive index, kneading into a polymer, and weather resistance. The particle size of the white pigment is not particularly limited, but the average particle size is preferably 0.2 μm or more in terms of kneading into polyester, melt spinnability, opacity and the like.

  These additives may be added in advance to the polymerization system when the polyester resin is obtained by polymerization. However, it is generally preferable to add an antioxidant or the like at the end of the polymerization, and the latter is particularly preferable when the polymerization system is adversely affected or when the additive is deactivated under the polymerization conditions. On the other hand, matting agents, heat stabilizers, and the like are preferably added at the time of polymerization because they are easily dispersed uniformly in the resin polymer.

  Moreover, it is preferable that the fiber assembly which consists of the multileaf polyester fiber concerning this invention is 85% or more of the opacity F shown by the formula mentioned later. This determination of opacity is particularly sensitive in white fabrics and light-colored systems, and can be determined more effectively.

  When the opacity F of the fiber assembly is less than 85%, the wear of the inner garment and the skin can easily be seen through the fabric, especially when the fabric is white or light-colored. On the other hand, when the value of the opacity F is 85% or more, the effect of preventing see-through is exhibited even in a thin white object.

  The multileaf polyester resin of the present invention has an intrinsic viscosity of 0.6 to 0.7, preferably 0.62 to 0.68, more preferably 0.63 to 0.66. When the intrinsic viscosity exceeds 0.7, the high-speed spinnability at the time of fiberization becomes extremely poor. In addition, even when spinning is possible and the target dyeing rate is obtained, the surface of the obtained woven or knitted fiber, such as dyeing spots or streaks in the tubular knitted dyed fabric, or the texture of the woven or knitted fabric is inferior The quality is lowered, which is not preferable for clothing. On the other hand, when the intrinsic viscosity is less than 0.6, not only is the fiber easily cut during spinning, but the productivity is poor, and the strength of the obtained fiber is low. Furthermore, even if spinning is possible and the target dyeing rate is obtained, the surface of the obtained woven or knitted fiber, such as dyeing spots or streaks occurring on the cylindrical knitted fabric, or the texture of the woven or knitted fabric is inferior The quality is lowered, which is not preferable for clothing.

  In the spinning step of the production method of the present invention, the polyester resin is spun from a die using a normal melt spinning apparatus.

Next, the polyester resin of the present invention is melt kneaded using, for example, a single screw extruder or a twin screw extruder. Temperature during the melt-kneading varies depending copolymerization amount of cyclohexane dicarboxylic acid component and adipic acid component, in order to obtain a plaque without stable melt kneading and stable spinnability and quality from the melting point of the polymer 10 It is preferable to melt-knead in a temperature range higher than -50 ° C, 20
It is more preferable that the temperature range be higher by -40 ° C.
Furthermore, the melting temperature from passing through the kneading equipment to reaching the spinning head also cannot be specified because it differs depending on the copolymerization amount of the cyclohexanedicarboxylic acid component and the adipic acid component, but it is stable without melting spots. In order to obtain a stable spinning property and quality, it is preferable to perform melt extrusion at a temperature range 30 to 60 ° C. higher than the melting point of the polymer.
More preferably, the temperature range is higher by 0 ° C.

  And the multileaf type | mold polyester fiber melt-spun by the above is once cooled to the temperature below the glass transition temperature, Preferably it is 10 degreeC or more lower than the glass transition temperature. The cooling method or cooling device in this case is not particularly limited as long as it is a method or device that can cool the spun polyester fiber to its glass transition temperature or lower, but a cooling air blowing tube or the like under the spinneret. It is preferable that a cooling air blowing device is provided, and cooling air is blown to the spun polyester fiber to cool it to a glass transition temperature or lower. At that time, the cooling conditions such as the temperature and humidity of the cooling air, the blowing speed of the cooling air, and the blowing angle of the cooling air to the spun yarn are not particularly limited, and the polyester fiber spun from the base is swayed in the fiber. Any condition may be used as long as it can be promptly and uniformly cooled down to the glass transition temperature or less while preventing the occurrence of. Among them, the cooling air is sprayed on the spinning fiber by setting the cooling air temperature to 20 ° C. to 30 ° C., the cooling air humidity to 20% to 60%, and the cooling air blowing speed to 0.4 to 1.0 m / sec. Cooling the spun polyester fiber with the direction perpendicular to the spinning direction is preferable because high-quality polyester fiber can be obtained smoothly. In addition, when cooling is performed under the above-described conditions using a cooling air blowing cylinder, a cooling air blowing cylinder having a length of about 80 to 120 cm is provided with a slight gap or no gap immediately below the spinneret. Is preferably arranged.

  Next, as a method for obtaining a stretched yarn with more efficient productivity and stable quality, after spinning, the yarn is once cooled below the glass transition temperature, and then directly heated to the heating zone, specifically a tube. A drawn yarn can be obtained by running in a device such as a mold heating cylinder, drawing and heat-treating, and taking off at a speed of 3500 to 5500 m / min after refueling. The heating temperature in the heating step needs to be a temperature at which stretching is easy, that is, a temperature not lower than the glass transition temperature but not higher than the melting point, specifically, preferably 30 ° C. or higher than the glass transition temperature, more preferably 50 ° C. or higher. preferable. Moreover, it is preferable that it is 20 degreeC or more lower than melting | fusing point, and it is more preferable that it is 30 degreeC or more lower. As a result, the yarn cooled below the glass transition temperature in the cooling step is heated with a heating device, thereby promoting and activating the molecular motion.

The oil agent is applied after passing through the stretching treatment step using a heating device. Thereby, the stretched yarn by an oil agent decreases. The oil agent is not limited as long as it is usually used for spinning polyester. The oiling method may be either oiling nozzle oiling or oiling roller oiling by a gear pump system. However, as the spinning speed is increased, the former method is free from unevenness on the yarn, and stable oil adhesion is possible. There are no particular restrictions on the amount of oil to be adhered, and it may be appropriately adjusted as long as it is in a range suitable for the effect of suppressing yarn breakage and raw yarn fluff and the process of knitting and knitting.
Among these, it is preferable to set the amount of oil to be adhered to 0.3 to 2.0% because a high-quality polyester fiber can be obtained smoothly, and more preferably 0.3 to 1.0%.

  And it is preferable to draw | stretch the stretched multileaf type | mold polyester fiber which consists of a series of processes mentioned above at 3500-5500 m / min, and it is more preferable that it is a take-up speed of 4000-5000 m / min. When the take-up speed of the polyester fiber is less than 3500 m / min, the productivity is lowered, and the fiber is not sufficiently drawn in the heating zone, and the mechanical properties of the resulting polyester fiber are lowered. When the take-up speed exceeds 5500 m / min, it is difficult to obtain a stable high-speed spinnability, and the fiber is not sufficiently drawn in the heating zone, so that the mechanical properties of the resulting multileaf polyester fiber are lowered.

  As for the dyeing rate of the multileaf polyester fiber obtained in the present invention, it is desirable that the dyeing rate at 95 ° C. is 70% or more and the dyeing rate at 100 ° C. is 90% or more. Below these dyeing rates, it is not preferred for general clothing applications because sufficient dyeing rates cannot be obtained even with easily dyeable dyes of medium to low molecular weight dyes (SE to E type). Furthermore, wool, cotton, Even if knitting and weaving with materials other than polyester, such as acrylic and polyurethane, it becomes difficult to obtain sufficient dyeability in a normal pressure environment.

  The multi-leaf type polyester fiber obtained by the present invention desirably has a wash fastness of 4th grade or more due to discoloration, attached contamination, and liquid contamination. If any of them is less than the fourth grade, it is not preferable for general clothing use from the viewpoint of handleability.

  Moreover, it is preferable that the multi-leaf type polyester fiber obtained by this invention is 4 or more grades in light fastness. When the light fastness is less than 4th grade, it is not preferable for general clothing use from the viewpoint of handleability.

  Furthermore, it is desirable that the multi-leaf type polyester fiber obtained in the present invention satisfies a breaking strength retention of 90% or more after alkali weight loss treatment. When the breaking strength retention is less than 90%, the yarn quality after alkali weight loss is deteriorated, resulting in a process failure during yarn processing and a product quality failure, which is not preferable for general clothing use.

  The multi-leaf type polyester fiber excellent in dyeability of the present invention is not limited to the drawn yarn obtained by the above production method, and an optimum spinning method is used to ensure the quality required for the final product and good processability. You can choose. More specifically, a spin draw method, a 2-step method in which a spinning raw yarn is collected and then drawn in a separate process, or a drawing speed of 2000 m / min or more without drawing is used as a non-drawn yarn. Also in the method of taking, a polyester product having a good atmospheric pressure dyeable quality can be obtained by making a product after passing through an arbitrary yarn processing step.

  EXAMPLES Hereinafter, although an Example demonstrates this invention in detail, these do not limit this invention. The following methods are used to evaluate the amount of dicarboxylic acid component copolymerization, the glass transition temperature of the polyester resin, the crystallization temperature, the intrinsic viscosity, the dyeing rate of the fiber obtained in the present invention, K / S, the fineness, and the physical properties of the fiber. Followed.

<Dicarboxylic acid component copolymerization amount>
The amount of copolymerization was determined by dissolving the polyester fiber in a heavy trifluoroacetic acid solvent at a concentration of 5.0 wt% / vol, and at 50 ° C., 500 MHz, ¹ H-NMR (JEOL nuclear magnetic resonance apparatus LA-500) apparatus. And measured.

<Glass transition temperature>
The temperature was measured at 10 ° C./min with a differential scanning calorimeter (DSC-60) manufactured by Shimadzu Corporation.

<Crystalization temperature>
The temperature was measured at 10 ° C./min with a differential scanning calorimeter (DSC-60) manufactured by Shimadzu Corporation.

<Intrinsic viscosity>
Measurement was performed using a mixed solvent of phenol / tetrachloroethane (volume ratio 1/1) as a solvent at 30 ° C. using an Ubbelohde viscometer (HRK-3 type, manufactured by Hayashi Seisakusho).

<Dyeing and dyeing rate>
The obtained fiber knitted fabric was scoured, dyed under the following conditions, subjected to reduction cleaning, and the dyeing rate was determined.
(staining)
Dye: Dianix NavyBlue SPH conc 5.0% omf
Auxiliary agent: Disper TL: 1.0 cc / l, ULTRA MT-N2: 1.0 cc / l
Bath ratio: 1/50
Dyeing temperature x time: 95-100 ° C x 40 minutes (reduction washing)
Sodium hydroxide: 1.0 g / L
Hydrosulfite sodium: 1.0 g / L
Amiradine D: 1.0 g / L
Bath ratio: 1/50
Reduction cleaning temperature x time: 80 ° C x 20 minutes (dyeing rate)
The stock solution before dyeing and the residual solution after dyeing are each diluted with acetone water (acetone / water = 1/1 mixed solution) to the same magnification, and the absorbance is measured for each. Asked.
Absorbance meter: spectrophotometer HITACHI
HITACHI Model 100-40
Spectrophotometer
Dyeing rate = (A−B) / A × 100 (%)
Here, A and B respectively indicate the following.
A: Absorbance of stock solution (acetone water diluted solution) B: Absorbance of dyeing residual solution (acetone water diluted solution)

<Dyeing concentration (K / S)>
The dyeing density was determined from the Kubelka-Munk equation shown below by measuring the reflectance R at the maximum absorption wavelength of the sample knitted fabric after dyeing.
Spectral reflectometer: spectrophotometer HITACHI
C-2000S Color Analyzer
K / S = (1-R) ² / 2R

<Washing fastness>
It measured based on the measuring method of JIS L-0844.

<Light fastness>
It measured based on the measuring method of JIS L-0842.

<Fineness>
It measured based on the measuring method of JIS L-1013.

<Break strength>
It calculated | required from the load-elongation curve obtained using the Instron type tensile tester.

<Elongation at break>
It calculated | required from the load-elongation curve obtained using the Instron type tensile tester.

<Spinnability>
Spinnability was evaluated according to the following criteria.
A: Spinning performance is very good, such as continuous spinning for 24 hours, no yarn breakage during spinning, and no fluff or loops in the obtained polyester fiber. Performs continuous spinning, and the yarn breakage during spinning occurs at a frequency of 1 or less, and the resulting polyester fiber has no fluff or loops at all or slightly, but the spinnability is almost good. △: 24 hours of continuous spinning, yarn breakage during spinning occurs up to 3 times, and spinnability is poor ×: 24 hours of continuous spinning occurs, yarn breakage during spinning occurs more than 3 times , Spinnability is extremely poor

<Strength retention>
After scouring the obtained fiber tubular knitted fabric, the weight of the alkali is reduced until the weight loss rate becomes 15% under the following conditions, and the tubular knitted fabric before and after the treatment is defibrated and an Instron type tensile tester is used. Then, the breaking strength was determined from the load-elongation curve, and expressed as the ratio of the breaking strength (retention rate) from the following formula.
Strength retention = (B / A) × 100 (%)
Here, A and B respectively indicate the following.
A: Breaking strength of a tubular knitted yarn after alkali weight reduction treatment B: Fracture strength of a tubular knitted yarn after alkali weight reduction treatment (alkali weight loss)
Sodium hydroxide: 40 g / L
Alkali weight loss temperature x time: 95-100 ° C x arbitrary time (weight loss rate = 15%)

<Porosity of fiber assembly (%)>
Three yarns were aligned and subjected to a lower twist of 2500 T / M, three of which were combined, and an optical micrograph of a fiber cross section obtained by cutting a twisted S400 T / M twist with a microtome was taken. The photograph was enlarged, cut into fibers and voids, and the porosity was determined from the weight ratio according to the above formula (I). However, about the fiber which has hollow parts, such as a hollow fiber, the hollow part was also calculated as a space | gap.
Porosity (%) = [(Cavity weight) / (Fiber weight part + Cavity weight)] × 100

<Deformation degree of fiber>
An optical micrograph of the fiber cross section of the fiber was measured, and measured and calculated by the following formula.
Deformity = R / L
(However, in the fiber cross section, L is the length AB of the line connecting the adjacent tip portions A and B, and R is the intersection of the depression D and the perpendicular line from D to the line AB located in the middle of the adjacent tip portions. The length CD when C is indicated.)

<Deformity retention rate (%)>
The degree of deformity after dyeing was dyed under the dyeing conditions described above, and the degree of deformity was measured after reduction cleaning. Prior to the dyeing process, the degree of unstained irregularity was measured.
Deformity retention rate (%) = (Deformation degree after dyeing process / Deformation degree before dyeing process) x 100

<Reflectance R (%)>
A taffeta fabric having a warp density of 38 / cm and a weft density of 28 / cm was measured with a Hitachi spectrophotometer “U-3400”, and the reflectance at a wavelength of 500 nm was determined from the obtained reflection curve.

<Opacity of fiber assembly (%)>
Using multi-leaf type polyester fibers with a single fineness of 2.2 denier for warp and weft, 38 warps / cm and 28 wefts / cm were produced, and this knitting was performed using Hitachi spectrophotometer "U-3400 type". The L ^* of the ground was measured and calculated by the following formula.
Opacity (%) = (L ^* _B / L ^* _W ) × 100
L ^* _B: L when the piled fabric (fiber aggregate) to the black matrix ^* value L ^* _W: L ^* value black matrix when the piled fabric (fiber aggregate) in white green body black plastic plate (L ^* Value = 12), white substrate indicates a standard white board (L ^* value = 100).

Example 1
Of the dicarboxylic acid components, 91 mol% is terephthalic acid, and all carboxylic acid components and ethylene glycol each containing 6.0 mol% of 1,4-cyclohexanedicarboxylic acid and 3.0 mol% of adipic acid, and the average A transesterification reaction and a polycondensation reaction were performed with titanium dioxide having a particle size of 0.3 μm to obtain a polyester resin polymer of the present invention. When the glass transition temperature and crystallization temperature of this raw material were measured, they were 72 ° C. and 144 ° C., respectively. Based on this raw material, spinning was performed at a spinning temperature of 260 ° C. and a single hole discharge rate of 1.57 g / min using a four-leaf type die having 24 holes and a cross-sectional shape as shown in FIG. A length of 1.0 m is set at a position 1.2 m below the spinneret after the cooling yarn of 60 ° C. and humidity of 60% is blown onto the spun yarn at a speed of 0.5 m / sec. The inlet guide system is 8 mm, the outlet guide system is 10 mm, the inner diameter is 30 mm, introduced into a tube heater (inner temperature 185 ° C.) and stretched in the tube heater, and then the yarn that has come out of the tube heater is lubricated with an oiling nozzle. A take-off roller was used to pick up at a speed of 4500 m / min to obtain 84T / 24f 4-leaf polyester filament. Table 1 shows the spinning conditions and spinnability at that time, and the results of dyeing fastness and strength retention of the obtained fiber. Using the four-leaf type polyester fiber obtained by the above production method, a taffeta having a raw machine density of 38 warps / cm and 28 wefts / cm was woven. This raw machine taffeta was treated with soda ash 2 g / l and actinol R-100 (manufactured by Matsumoto Yushi) at 100 ° C. for 30 minutes for scouring. Subsequently, heat setting was performed at 180 ° C. using a pin tenter. The dyeing rate of each woven fabric was 85% at 95 ° C., 93% at 100 ° C., and K / S = 26. Table 1 shows the degree of irregularity, the porosity of the aggregate of drawn yarns, the reflectance, the fastness to washing, the fastness to light, and the opacity. As shown in Table 1, the fiber obtained by the above method had a quality without any problems. Furthermore, the strength retention rate and deformity retention rate after 15% alkali weight loss were 96%, respectively, and good quality.

(Examples 2 to 5)
A polyester resin and a fiber were produced in the same manner as in Example 1 except that the copolymerization amount of 1,4-cyclohexanedicarboxylic acid and adipic acid in the polyester resin and the fiber cross section were changed.
Specifically, a copolymer having the thermal properties shown in Table 1 was produced, and this polymer was spun in the same manner as in Example 1 except that a base for changing the fiber cross section was used. A 24f polyester filament was obtained. Table 1 shows the physical properties of the obtained fiber.
All had good spinnability, normal-pressure dyeability (dyeing rate, K / S, fastness), strength retention rate, and irregularity retention rate, and had no problem.

(Comparative Examples 1-6)
A polyester resin and a fiber were produced in the same manner as in Example 1 except that the copolymerization amount of 1,4-cyclohexanedicarboxylic acid and adipic acid in the polyester resin and the fiber cross section were changed.
Specifically, a copolymer having the thermal properties shown in Table 1 was produced, and this polymer was spun in the same manner as in Example 1 except that a base for changing the fiber cross section was used. A 24f polyester filament was obtained. Table 1 shows the physical properties of the obtained fiber.

  In Comparative Examples 1 and 2, the cross section was changed to a round cross section and a single hole hollow. As a result, the porosity and reflectance of the fabric were insufficient, and the opacity value of the fiber assembly was inferior.

  In Comparative Example 3, since the amount of 1,4-cyclohexanedicarboxylic acid copolymerized was small, the dyeing rate and dyeing concentration were insufficient, and the fiber physical properties did not show normal pressure dyeability.

  In Comparative Example 4, the copolymerization amount of 1,4-cyclohexanedicarboxylic acid was 18.0 mol%, and the copolymerization amount of terephthalic acid was 77 mol%, which was outside the range of the composition of the present invention. As a result, the obtained fiber had a sufficient dyeing rate and dyeing concentration, but was inferior in spinnability.

  In Comparative Example 5, since the copolymerization amount of adipic acid is small, even if 1,4-cyclohexanedicarboxylic acid is sufficiently copolymerized, the dyeing rate and dyeing concentration are insufficient, and the atmospheric pressure dyeability is increased. Fiber properties not shown were obtained.

  In Comparative Example 6, since the amount of adipic acid copolymerized was large, the dyeing rate and dyeing concentration were sufficient, but the spinnability was greatly inferior.

According to the present invention, it is possible to perform dyeing with excellent darkness and fastness in dyeing under an atmospheric pressure environment, and stable quality and processability in a direct spinning drawing method or other general melt spinning methods. Can be obtained.
Specifically, the normal pressure dyeable polyester fiber of the present invention has a quality comparable to that of conventional polyester fibers, so that general clothing such as formal or casual fashion clothing for men and women, sports use, etc. It can be used effectively in a wide variety of applications such as uniforms. Further, it can be effectively used for general material applications, for example, interior material applications such as automobiles and airplanes, living material applications such as shoes and bags, and industrial material applications such as curtains and carpets.

Claims (7)

A fiber made of a polyester resin and having a multilobal cross-sectional shape, wherein the polyester resin is a copolymer comprising a dicarboxylic acid component and a glycol component, and 80 mol% or more of the dicarboxylic acid component is a terephthalic acid component And / or an ester-forming derivative thereof, and 4.0 to 12.0 mol% is a cyclohexazadicarboxylic acid component and / or an ester-forming derivative thereof, and 2.0 to 8.0 mol% is adipine. An acid component and / or an ester-forming derivative thereof , and the total amount of copolymerization of other dicarboxylic acid components other than the terephthalic acid component, cyclohexanedicarboxylic acid component, and adipic acid component is 10.0 mol% or less, copolymerization amount of isophthalic acid component is 10 mol% or less, the copolymerization amount of metal sulfonate is not more than 1.0 mol%, the Recall component polyester fiber characterized in that a main component of ethylene glycol component and / or an ester-forming derivative thereof.   The polyester fiber according to claim 1, wherein the cross-sectional shape has 3 to 10 leaves. The polyester fiber according to claim 1 or 2, wherein in the cross-sectional shape, the degree of irregularity is in a range of 0.05 to 0.80. The polyester fiber according to claim 1, wherein among the dicarboxylic acid components, isophthalic acid and an ester-forming derivative thereof are 5 mol% or less.   The polyester fiber according to any one of claims 1 to 4, wherein the fastness to washing of discoloration, attached contamination, and liquid contamination is all 4th or higher.   The polyester fiber according to any one of claims 1 to 5, which has a light fastness of 4 or higher.   A fiber assembly comprising the polyester fiber according to any one of claims 1 to 6, wherein a reflectance R at a wavelength of 500 nm is 85% or more and a porosity is 20 to 60%. Fiber assembly.

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