JP2006169700A - Combined polyester filament yarn - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a combined polyester filament yarn excellent in hue, able to be industrially produced, generating very little foreign materials around a spinneret even when continuously melt spun for a long time through the spinneret, able to stably combine filaments and excellent in dyed quality. <P>SOLUTION: The combined polyester filament yarn is prepared by drawing and arranging, combining, twisting or compounding two or more filaments. At least one species of structural yarns or monofilaments has 0-10 ppm content of a metal having ≥5.0 specific gravity. The combined polyester filament yarn includes monofilaments having ≤5 dtx. monofilament denier. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a polyester mixed yarn for clothing. More specifically, the content of metal elements having a specific gravity of 5.0 or more, particularly antimony and germanium, is extremely small, excellent in hue, and the amount of deposits on the die is extremely small even when melt-spun continuously for a long time. The present invention relates to a polyester blended yarn with improved productivity by producing a finished raw yarn in the process and excellent blended yarn quality such as fluff and dyeing.

It is well known that polyesters greatly depend on the reaction rate and the quality of the resulting polyester depending on the type of catalyst used in the polycondensation reaction stage. As a polycondensation catalyst of polyethylene terephthalate, an antimony compound is most widely used because it has excellent polycondensation catalyst performance and a polyester having a good color tone can be obtained.
However, when an antimony compound is used as a polycondensation catalyst, if the polyester is melt-spun continuously over a long period of time, foreign matter (hereinafter sometimes referred to simply as “base foreign matter”) is deposited and melted around the mouthpiece hole. A bending phenomenon (bending) of the polymer flow occurs, and this causes a problem of a decrease in process passability such as generation of fluff and / or yarn breakage in the spinning and drawing processes.
In particular, polyester blended yarn for clothing is often used as a warp in the weaving process to form a fabric later, in order to maximize its characteristics. At that time, weaving productivity depends on the number of fluff of the blended yarn. Will cause serious problems. Dyed quality and leveling are one of the most important qualities for clothing fibers. In the past, improvements in fluff and dyeing quality have long been studied for polyester fibers.
In order to suppress the foreign matter from the die, it is effective to not use antimony as a polymerization catalyst for polyethylene terephthalate. However, if the method does not use antimony, the color of the yarn will be lowered. When it was used after dyeing, it became a serious problem.

In order to solve such a problem, a product obtained by reacting a titanium compound with a specific phosphorus compound (see, for example, Patent Document 1 and Patent Document 2), or a titanium compound and a specific phosphorus compound It is disclosed that an unreacted mixture or a reaction product (see, for example, Patent Document 3) is used as a catalyst for polyester production. Indeed, according to this method, the melt heat stability of the polyester is improved, and the hue of the resulting polymer is greatly improved. However, these methods have a problem that the productivity of the polyester is slightly inferior because the polymerization reaction rate during the production of the polyester is slow.
Accordingly, there has been a demand for a polyester blended yarn that does not use antimony as a catalyst, is excellent in processability in the hue and spinning, stretching process, and blending process, and that does not reduce the productivity during polyester production.
International Publication No. 01/00706 Pamphlet International Publication No. 03/008479 Pamphlet International Publication No. 03/027166 Pamphlet

  The object of the present invention is excellent in hue, can be produced industrially, even if melt spinning continuously for a long time through the spinneret, the amount of foreign matter generated in the die is very small, and can be stably mixed. The object is to provide a polyester blended yarn excellent in dyeing quality.

The present invention is a metal in which two or more types of yarns are aligned, mixed, twisted, or compounded, and at least one of the constituent yarns or single yarns has a specific gravity of 5.0 or more. The present invention relates to a polyester mixed yarn characterized by comprising a single yarn having an element content of 0 to 10 ppm by weight and a single yarn fineness of 5 digits or less.
Here, the polyester blended yarn of the present invention has a maximum absorption wavelength in the visible light absorption spectrum in the range of 380 to 780 nm measured in a chloroform solution having a concentration of 20 mg / L and an optical path length of 1 cm in the range of 540 to 600 nm. In addition, an organic compound color matching agent satisfying all of the following formulas (1) to (4) in which the ratio of the absorbance at each wavelength below to the absorbance at the maximum absorption wavelength is 0.1 to 10 ppm by weight with respect to the total weight. It is preferable to contain.

[In the above formula, A ₄₀₀ , A ₅₀₀ , A ₆₀₀ and A ₇₀₀ are the absorbance in the visible light absorption spectrum at wavelengths of 400 nm, 500 nm, 600 nm and 700 nm, respectively, and A _max is the absorbance in the visible light absorption spectrum at the maximum absorption wavelength. Represents. ]

  According to the present invention, it is possible to eliminate the deterioration of hue, which is a drawback of polyesters that do not use Sb or Ge catalysts, while maintaining the excellent properties of polyesters. As a result, the blended yarn obtained by blending the yarn obtained in this way is excellent in processability in the hue and spinning, drawing process and blending process, and the productivity at the time of polyester production does not decrease. Good hue and stain.

The present invention will be described in detail below.
The aromatic polyester in the present invention is a polyester obtained by a polycondensation reaction between an aromatic dicarboxylic acid component typified by terephthalic acid, naphthalenedicarboxylic acid, or an ester-forming derivative thereof, and a glycol component. This polyester may be a copolyester, and as a copolymer component, a component other than an aromatic dicarboxylic acid component and a glycol component, for example, an aliphatic dicarboxylic acid component, an aromatic dihydroxy compound, and an oxycarboxylic acid component are copolymerized. May be.
The aromatic polyester is preferably a polyester selected from the group consisting of polyethylene terephthalate, polyethylene naphthalate, polytrimethylene terephthalate, polytrimethylene naphthalate, polytetramethylene terephthalate, and polytetramethylene naphthalate. Of these, polyesters having polyethylene terephthalate as the main constituent are particularly preferred.
The “main constituent component” indicates that 80 mol% or more of all repeating units of the polyester is an aromatic polyester.

  The metal element having a specific gravity of 5.0 or more in the present invention is usually derived from a metal compound contained in a catalyst, a metal color adjuster, a matting agent, or the like contained in a polyester. Specifically, antimony, germanium, manganese, cobalt, cerium, tin, zinc, lead, cadmium, and the like are applicable. On the other hand, titanium, aluminum, calcium, magnesium, sodium, potassium, and the like do not correspond to metals having a specific gravity of 5.0 or more.

The polyester composition used in the present invention needs to have a content of a metal element having a specific gravity of 5.0 or more of 0 to 10 ppm by weight. The characteristics and properties vary depending on the type of metal contained. For example, when the content of antimony metal is more than 10 ppm by weight, it becomes a foreign object during yarn production or film formation and adheres to the periphery of the die or die, and continues for a long time. Adversely affects moldability. In the case of germanium, since it is expensive per se, the price of the resulting polyester composition increases when the content increases, which is not preferable. In the case of lead, tin, cadmium, etc., the metal element itself is toxic, so it is not preferable to contain it in a large amount in the polyester. The content of the metal element is preferably 0 to 7 ppm by weight, and more preferably 0 to 5 ppm by weight.
In order to make the content of the metal element 10 ppm by weight or less, it is desirable to use a catalyst, a color adjusting agent, and a matting agent that do not contain the metal.

The polyester mixed yarn of the present invention is a yarn obtained by arranging two or more types of yarns, and is achieved by a mixed yarn comprising a single yarn having a single yarn fineness of 5 digittex or less.
A single yarn fineness of 5 dtex or less is important as a mixed yarn for clothing. This is a property that is indispensable for realizing a fine touch close to or similar to that of natural fibers due to the fineness of the single yarn, which is a factor affecting the texture and texture after forming the fabric. In particular, a single yarn exceeding 5 decitex is hard to touch, and it is easy to feel the hardness, which is a defect of synthetic fibers, and it tends to be a monotonous texture. On the other hand, when the single yarn fineness is 5 dtex or less, preferably 3.5 dtex or less, it is possible to achieve both the delicate touch unique to the mixed yarn and the excellent color development after dyeing. The single yarn fineness is preferably 3.5 to 1.0 dtex.

Moreover, the polyester composition used for this invention needs to contain 0.1-10 weight ppm of color adjusting agents. The color adjusting agent represents an organic polyaromatic ring dye or pigment. Specifically, as described later, a blue color adjuster, a purple color adjuster, a red color adjuster, an orange color adjuster, and the like can be given. These may be used as a single species or as a combination of a plurality of species.
Further, in the color adjusting agent, the maximum absorption wavelength in the absorption spectrum in the region of 380 to 780 nm of the color adjusting agent solution is in the range of 540 to 600 nm, and the concentration is 20 mg / L, and the chloroform solution has an optical path length of 1 cm. It is preferable that the ratio of the absorbance at each wavelength to the absorbance at the maximum absorption wavelength satisfies all of the following formulas (1) to (4).

[In the above formula, A ₄₀₀ , A ₅₀₀ , A ₆₀₀ and A ₇₀₀ are the absorbance in the visible light absorption spectrum at wavelengths of 400 nm, 500 nm, 600 nm and 700 nm, respectively, and A _max is the absorbance in the visible light absorption spectrum at the maximum absorption wavelength. Represents. ]

  Here, the visible light absorption spectrum is usually a spectrum measured by a spectrophotometer. When the maximum absorption wavelength of the visible light absorption spectrum of the chloroform solution of the color adjusting agent contained in the polyester blended yarn of the present invention is less than 540 nm, the redness of the resulting polyester blended yarn becomes strong, while 600 nm When exceeding, since the bluishness of the obtained polyester mixed yarn becomes strong, it is not preferable. The range of the maximum absorption wavelength is more preferably in the range of 550 to 590 nm.

  Further, when a visible light absorption spectrum was measured at an optical path length of 1 cm for a chloroform solution having a concentration of 20 mg / L of the organic compound color matching agent used in the present invention, the absorbance at each wavelength shown above relative to the absorbance at the maximum absorption wavelength. Is unfavorable because the resulting polyester blended yarn will be highly colored if any one of the above formulas (1) to (4) deviates. More preferably, the ratio of absorbance at each wavelength satisfies all of the following formulas (6) to (9).

[In the above formula, A ₄₀₀ , A ₅₀₀ , A ₆₀₀ and A ₇₀₀ are the absorbance in the visible light absorption spectrum at wavelengths of 400 nm, 500 nm, 600 nm and 700 nm, respectively, and A _max is the absorbance in the visible light absorption spectrum at the maximum absorption wavelength. Represents. ]

  Furthermore, when the content of the color adjusting agent contained in the polyester mixed yarn of the present invention is less than 0.1 ppm by weight, the yellow color of the polyester mixed yarn becomes strong. On the other hand, when the content exceeds 10 ppm by weight, the brightness is weakened and the blackness is visually increased, which is not preferable. The content of the color adjusting agent is more preferably in the range of 0.3 ppm to 9 ppm by weight.

In order to make the range of the visible light absorption spectrum of the organic compound color matching agent used in the present invention within the above range, a weight ratio of a blue color matching pigment and a purple color matching pigment is used as the color adjusting agent. It is preferable to use in a range of 90:10 to 40:60, or to use a blue color adjusting dye and a red or orange color adjusting dye in a weight ratio of 98: 2 to 80:20.
Here, the blue color adjusting dye is generally described as “Blue” among commercially available color adjusting dyes, and specifically, the maximum in the visible light absorption spectrum in a solution. The absorption wavelength is about 580 to 620 nm.
Similarly, the purple color-modifying dye is the one described as “Violet” among commercially available color-adjusting dyes, and specifically, the maximum absorption in the visible light absorption spectrum in the solution. The wavelength is about 560 to 580 nm.
The red color-modifying dye is described as “Red” among commercially available color-adjusting dyes. Specifically, the maximum absorption wavelength in a visible light absorption spectrum in a solution is 480. It is about ˜520 nm.
The orange color-modifying dye is one that is described as “Orange” among commercially available color-adjusting dyes.

As these color adjusting dyes, oil-soluble dyes are particularly preferable. As specific examples, blue color adjusting dyes include C.I. I. Solvent Blue 11, C.I. I. Solvent Blue 25, C.I. I. Solvent Blue 35, C.I. I. Solvent Blue 36, C.I. I. Solvent Blue 45 (Telasol Blue RLS), C.I. I. Solvent Blue 55, C.I. I. Solvent Blue 63, C.I. I. Solvent Blue 78, C.I. I. Solvent Blue 83, C.I. I. Solvent Blue 87, C.I. I. Solvent Blue 94 and the like.
Examples of purple color adjusting pigments include C.I. I. Solvent Violet 8, C.I. I. Solvent Violet 13, C.I. I. Solvent Violet 14, C.I. I. Solvent Violet 21, C.I. I. Solvent Violet 27, C.I. I. Solvent Violet 28, C.I. I. Solvent Violet 36 etc. are mentioned.
Examples of red color adjusting pigments include C.I. I. Solvent Red 24, C.I. I. Solvent Red 25, C.I. I. Solvent Red 27, C.I. I. Solvent Red 30, C.I. I. Solvent Red 49, C.I. I. Solvent Red 52, C.I. I. Solvent Red 100, C.I. I. Solvent Red 109, C.I. I. Solvent Red 111, C.I. I. Solvent Red 121, C.I. I. Solvent Red 135, C.I. I. Solvent Red 168, C.I. I. Solvent Red 179 is exemplified.
Examples of the orange color adjusting dye include C.I. I. Solvent Orange 60 etc. are mentioned.

Here, when the blue color-modifying dye and the purple color-changing dye are used in combination, when the weight ratio of the blue color-changing dye is larger than the weight ratio 90:10, the color a ^* of the resulting polyester composition When the value is small and green, and the weight ratio of the blue color-modifying dye is smaller than 40:60, the color a ^* value becomes large and red.
Similarly, in the case where a blue color adjusting dye and a red or orange color adjusting dye are used in combination, when the weight ratio of the blue color adjusting dye is larger than 98: 2, the resulting polyester composition If the color a ^* value is small and green, and the weight ratio of the blue color adjusting dye is smaller than 80:20, the color a ^* value is large and red.
The color adjusting dye is a combination of a blue color adjusting dye and a purple color adjusting dye in a weight ratio of 80:20 to 50:50, or a blue color adjusting dye and a red or orange color. More preferably, the color adjusting pigment is used in a mass ratio of 95: 5 to 90:10.

The polyester multifilament used in the blended yarn of the present invention is preferably produced by melt spinning the polyester composition dried as described above in the range of 270 ° C. to 300 ° C. The melt spinning speed is 4 This is achieved by a spinning take-up speed of 5,000 m / min or more, preferably 4,500 m / min or more, more preferably 4,500 to 6,000 m / min.
The polyester multifilament used in the present invention is obtained by melt spinning the above polyester composition in the range of 270 to 300 ° C., taking it up at 500 to 2,000 m / min, and further stretching it as necessary. Can also be obtained. The stretching may be performed separately after winding the unstretched fiber once, or may be performed continuously after the unstretched fiber is spun off.

The polyester mixed yarn of the present invention is a multifilament containing at least one single filament having a metal element content of specific gravity of 5.0 or more of 0 to 10 ppm by weight and a single yarn fineness of 5 digittex or less. Using two or more types of multifilaments, for example, while applying overfeed of 1 to 5%, using a known interlace nozzle, the nozzle compressed air is 15 to 90 / m. It can be obtained as the polyester mixed yarn of the present invention by adjusting the pressure and entangled with the mixed fiber.
The total fineness of the polyester blended yarn of the present invention is usually 30 to 250 dtex, preferably 50 to 200 dtex, and the total number of filaments is usually 12 to 72 filaments, preferably about 24 to 48 filaments.

  The present invention will be further described in the following examples, but the scope of the present invention is not limited by these examples. Various measurement items in the examples were evaluated as follows.

(A) Intrinsic viscosity A dilute solution obtained by dissolving a polyester composition chip in orthochlorophenol at 100 ° C for 60 minutes was determined from a value measured at 35 ° C using an Ubbelohde viscometer.
(B) Qualitative analysis of metal components with a specific gravity of 5.0 or more in the polymer The polymer sample was mixed with ammonium sulfate, sulfuric acid, nitric acid and perchloric acid, wet-decomposed at about 300 ° C for 9 hours, diluted with distilled water, and manufactured by Rigaku. Qualitative analysis was performed using an ICP emission analyzer (JY170 ULTRACE), and the presence or absence of a metal element having a specific gravity of 5.0 or more was confirmed. About the metal element with which existence of 1 weight ppm or more was confirmed, the element content was shown.

(C) Titanium, aluminum, antimony, manganese, phosphorus content soluble in polyester in the polymer:
The amount of titanium element, aluminum element, antimony element, manganese element and phosphorus element soluble in the polyester in the polymer has a flat surface with a compression press machine after a granular polymer sample is heated and melted on an aluminum plate. A test molded body was prepared and obtained using a fluorescent X-ray apparatus (Model 3270E manufactured by Rigaku Corporation). However, regarding the amount of titanium element in the polyester composition to which titanium oxide was added as a matting agent, the sample was dissolved in orthochlorophenol and then extracted with 0.5 N hydrochloric acid. The extract was quantified using a Hitachi Z-8100 atomic absorption spectrophotometer. Here, when dispersion of titanium oxide was confirmed in the extract after extraction with 0.5 N hydrochloric acid, the titanium oxide particles were settled with a centrifuge, and only the supernatant was recovered by the gradient method. Went. By these operations, even if the polyester composition contains titanium oxide, the titanium element soluble in the polyester can be quantified.

(D) Diethylene glycol content:
The polyester chip was decomposed using hydrazine hydrate (hydrated hydrazine), and the content of diethylene glycol in the decomposition product was measured using gas chromatography (manufactured by Hewlett-Packard (HP 6850)).
(E) Weight reduction start temperature of color adjusting agent Using a TAS-200 thermobalance manufactured by Rigaku Corporation, the temperature was measured in a nitrogen atmosphere at a heating rate of 10 ° C./min according to JIS K7120.

(F) Hue (L * value, a * value, b * value):
・ Chip:
The polyester chip was melted at 285 ° C. under vacuum for 10 minutes, molded into an aluminum plate with a thickness of 3.0 ± 1.0 mm, immediately quenched in ice water, and the plate was dried at 140 ° C. for 1 hour. Crystallization was performed. Then, it put on the white standard plate for color difference adjustment, and measured the hunter L * and b * of the plate surface using the Minolta Co., Ltd. Hunter type color difference meter (CR-200 type). L * indicates lightness, and the larger the value, the higher the lightness, and b * the greater the value, the greater the degree of yellowing. Other detailed operations were performed according to JIS Z-8729.
·fiber:
After making the fiber into a tubular knitting by a conventional method, four knitted fabrics were overlapped and measured using a Hunter type color difference meter (CR-200 type) manufactured by Minolta Co., Ltd.

(G) Base foreign body height Spinning was carried out continuously for 4 days, and the height of the layer of deposits generated on the outer edge of the base outlet was measured. As the height of the deposit layer increases, bending occurs in the filament flow of the discharged polyester melt, and the moldability of the polyester decreases. That is, the height of the deposit layer generated in the spinneret is an index of the moldability of the polyester.

(I) Dyeing spot Polyester blended yarn is about 120m long, washed with water for 5 minutes, and 2% of the sample using Terra Top Blue (Ciba Specialty Chemicals Co., Ltd.), dyeing bath After standing at 40 ° C for 10 minutes with Polyesca DS (manufactured by Yoyo Chemical Co., Ltd.) at a rate of 0.2% of the liquid, the temperature was raised to 100 ° C over 30 minutes, and at 100 ° C for 30 minutes. Stained. After drying for 10 minutes, the inspector visually determined the stain on the dyed cylinder, and rated it according to the following criteria.
Level 1: There is no streak-like or speckled spots, and the whole is uniformly dyed.
Level 2: Streaky and speckled spots are slightly recognized, but acceptable as a good product.
Level 3: Many strong streaks or large speckled dyed spots are observed.

(G) Texture A plain weave structure was formed using polyester mixed yarn for warp and weft, and after bath washing, refining, dyeing and heat setting, the inspector made a sensory judgment and rated according to the following criteria.
Level 1: Very soft texture and fine surface feel.
Level 2: Soft texture, good surface feel and acceptable range.
Level 3: Hard texture and rough surface.

(S) Warper Fluff In the process of preparing warp for warp evaluation, the number of fluff was measured on the warper using a counter. In the warping, 1,000 yarns were set up, and a yarn length of 500,000 m was evaluated, and the number of fluffs per million m was calculated.

[Reference Example 1] Measurement of visible light absorption spectrum of color adjusting agent (color adjusting dye), preparation of color adjusting agent C.I. I. Solvent Blue 45 (manufactured by Clariant Japan) and C.I. I. Solvent Violet 36 (manufactured by Arimoto Chemical Co., Ltd.) was used as a chloroform solution with a weight ratio of 2: 1 and a concentration of 20 mg / L, and filled in a quartz cell with an optical path length of 1 cm. After filling, a visible light absorption spectrum in a visible light region of 380 to 780 nm was measured using a Hitachi spectrophotometer U-3010 type. The ratio of the absorbance at each wavelength of 400, 500, 600 and 700 nm to the maximum absorption wavelength and the absorbance at that wavelength was measured. The results are shown in Table 1. In addition, when adding a color adjusting agent in the polyester production process in Examples and Comparative Examples, it is dissolved or dispersed so as to have a concentration of 0.1% by weight with respect to a glycol solution used as a raw material at a temperature of 100 ° C. Prepared.

* 1: Ratio of absorbance at each wavelength to absorbance at the maximum absorption wavelength

[Reference Example 2] Synthesis of Titanium Catalyst A 1/2 mole of tetrabutoxytitanium with respect to trimellitic anhydride was added to an ethylene glycol solution (0.2% by weight) of trimellitic anhydride at 80 ° C under normal pressure in air. The reaction was continued for 60 minutes. Thereafter, it was cooled to room temperature, and the produced catalyst was recrystallized with 10 times the amount of acetone. The precipitate was filtered through filter paper and dried at 100 ° C. for 2 hours to obtain the target compound. This is designated as titanium catalyst A.

[Example 1]
In a mixture of 100 parts by weight of dimethyl terephthalate and 70 parts by weight of ethylene glycol, 0.016 part by weight of the titanium catalyst A prepared in Reference Example 2 was charged into a SUS container capable of pressure reaction. A 0.07 MPa pressure was applied and the ester exchange reaction was carried out while raising the temperature from 140 ° C. to 240 ° C., and then 0.023 parts by weight of triethylphosphonoacetate was added to complete the ester exchange reaction. Thereafter, 1.5 parts by weight of an ethylene glycol slurry containing 20% by weight of titanium oxide and 0.2 parts by weight of a 0.1% by weight ethylene glycol solution of the color adjusting agent prepared in Reference Example 1 were added to the reaction product. Then, the temperature was raised to 290 ° C., and a polycondensation reaction was performed in a high vacuum of 30 Pa or less to obtain a polyester composition. Furthermore, it was chipped according to a conventional method. The obtained polyester had an intrinsic viscosity of 0.63, a diethylene glycol content of 1.0% by weight, and a color L ^* 71, a ^* -5, and b ^* 6.

The polyethylene terephthalate pellets were dried at 150 ° C. for 5 hours, then extruded through a screw extruder, passed through a discharge nozzle, scraped at a scraping speed of 1,200 m / min, 210 dtex, and 24 filament counts not yet passed. A drawn yarn was obtained.
This undrawn yarn is preheated and heat set to 3.0 times to obtain a 70 dtex drawn yarn, and then mixed with a 30 dtex high shrink yarn showing a higher shrinkage ratio than this drawn yarn by a conventional method. , 100 decitex mixed fiber was obtained.
Table 2 summarizes the yarn breaking rate, the drawing / mixing process passability, the hue of the mixed yarn, and the dyed spots when the undrawn yarn was produced. The polyester blended yarns obtained in Table 2 have good processability and good hue and dyeing.

[Examples 2-3]
It wound up as conditions similar to Example 1 except having changed the number of holes in a discharge nozzle. Table 2 summarizes the spinning breakage rate, the physical properties of the polyester blended yarn, the process passability, the hue, and the dyed spots.

[Comparative Example 1]
A mixture of 100 parts by weight of dimethyl terephthalate and 70 parts by weight of ethylene glycol was charged with 0.032 parts by weight of manganese acetate tetrahydrate in a reactor equipped with a stirrer, a rectifying column and a methanol distillation condenser, and 140 ° C. The ester exchange reaction was carried out while distilling out the methanol produced as a result of the reaction while gradually raising the temperature to 240 ° C. Thereafter, 0.02 part by weight of trimethyl phosphate was added to complete the transesterification reaction. Subsequently, the obtained reaction product was transferred to a reaction vessel equipped with a stirrer, a nitrogen inlet, a vacuum port, and a distillation device, 0.045 parts by weight of antimony trioxide was added, and the temperature was raised to 290 ° C., 30 Pa A polycondensation reaction was performed under the following high vacuum to obtain a polyester composition. Furthermore, it was chipped according to a conventional method. The obtained polyester had an intrinsic viscosity of 0.63, a diethylene glycol content of 0.7% by weight, and a color L ^* 72, a ^* -5, and b ^* 6. This polyethylene terephthalate pellet was wound up as a multifilament in the same manner as in Example 1. Table 2 summarizes the spinning breakage rate, the physical properties of the polyester blended yarn, the process passability, the hue, and the dyed spots.

* 2: Titanium element concentration * 3: Phosphorus element concentration

  As is clear from Table 2, the polyester yarn of the present invention has significantly less foreign material generated during melt spinning than the level containing antimony trioxide as a polymerization catalyst (Comparative Example 1). The performance which the rate was low and the color tone and dyeing of the polyester mixed yarn were also good was obtained.

The polyester blended yarn of the present invention is excellent in suppressing spun yarn breakage due to the growth of a foreign object in the spinneret with the spinning time, and in controlling yarn breakage due to fluff and dyeing in the fabric forming process after blending. Useful for.

Claims (2)

  The content of a metal element in which at least one of the constituent yarns or single yarns is a yarn in which two or more types of yarns are aligned, mixed, twisted, or compounded, and the specific gravity is 5.0 or more. Is a polyester mixed yarn characterized by comprising a single yarn having a single yarn fineness of 5 digitex or less. The maximum absorption wavelength in the visible light absorption spectrum in the region of 380 to 780 nm measured in a chloroform solution with a concentration of 20 mg / L and an optical path length of 1 cm is in the range of 540 to 600 nm, and the following wavelengths with respect to the absorbance at the maximum absorption wavelength: The polyester mixed yarn according to claim 1, comprising 0.1 to 10 ppm by weight of an organic compound color-matching agent satisfying all of the following formulas (1) to (4):