KR20050055321A - Polyester microfiber having superior dyeability - Google Patents

Abstract

The present invention relates to a polyester microfiber having excellent dyeability, and the polyester microfiber having excellent dyeability of the present invention has a terephthalic acid as a main component and a polyalkylene glycol ether having a number average molecular weight of 200 to 2,000 with respect to the terephthalic acid, 1 to 10% by weight of the mixture is copolymerized and the polyalkylene glycol ether / terephthalic acid by adjusting the molar ratio (G value) of 1.05 to 1.15 to prepare a polyester polymer, the polymer is a glass transition temperature (Tg), 330 It is -350K, melt temperature (Tm), 510-525K, Tm / Tg ratio satisfy | fills 1.51-1.55, and intrinsic viscosity is 0.5-0.7 dl / g, The polymer is delayed at the time of melt spinning A single yarn fineness of 0.1 to 0.5 denier and a single yarn count of 70 or more were produced by spinning the length of the cooling section to 20 mm or less and the distance between the cooling air ejection surface and the thread thread of 2 mm to 30 mm. The present invention relates to steer microfibers. The polyester microfibers of the present invention not only have the same physical properties as the conventional polyester microfibers, but also have excellent spinning processability and deep color dyeing.

Description

POLYESTER MICROFIBER HAVING SUPERIOR DYEABILITY}

 The present invention relates to a polyester microfiber having excellent dyeability, and more particularly, a polyalkylene glycol ether having a number average molecular weight of 200 to 2,000 as a main component and mixed at 1 to 10% by weight with respect to the terephthalic acid. Copolymerization, and a polyester polymer was prepared by adjusting the molar ratio (G value) of polyalkylene glycol ether / terephthalic acid to 1.05 to 1.15, and the polymer was prepared by delayed cooling part length and cooling air outlet surface under the spinneret. The present invention relates to a polyester microfine fiber having excellent dyeing property, 0.1 to 0.5 denier, and single yarn number of 70 or more, manufactured by melt spinning by controlling the distance between yarns.

Recently, in the polyester fiber industry, development of high value-added differentiating materials is actively underway. As a result, single yarn fineness is 1.0 denier or less, followed by the development of ultrafine fibers. There is a growing interest in developing this improved or added microfiber.

The polymerization method of polyester can be divided into two types based on starting material. The first method is a TPA polymerization method using terephthalic acid (hereinafter referred to as "TPA") as a raw material, which is currently adopted in most polyester industries. Specifically, the above method is a method of directly esterifying TPA and ethylene glycol to prepare bishydroxy ethyl terephthalate and their low polymerization oligomers, and then polycondensing under high vacuum. The second method is a DMT polymerization method using dimethyl terephthalate (hereinafter referred to as "DMT") as a raw material. This method is a method of transesterification of DMT and ethylene glycol in the presence of a catalyst to prepare bishydroxy ethyl terephthalate and their low polymerization oligomers and then to polycondensate under high vacuum. At this time, the second method, DMT polymerization, uses metal salts such as zinc acetate, manganese acetate and magnesium acetate as catalysts for the transesterification reaction between DMT and ethylene glycol. After the preparation of the polymer, the depolymerization of the polymer and the stabilizer (stabilizer) should be added because it has activity against sunlight such as UV. Therefore, in the production of the same amount of polymer, there is a problem that the DMT polymerization method has a 17% additional production cost and a relatively low productivity compared to the TPA polymerization method.

On the other hand, the TPA polymerization method, which is the first method, does not use a catalyst for the esterification reaction of TPA and ethylene glycol, and does not require a separate stabilizer because of its low activity of antimony trioxide, which is mainly used as a polycondensation catalyst. It is advantageous in terms of manufacturing cost and productivity.

As an example using such a TPA polymerization method, Japanese Unexamined Patent Application Publication No. Hei 9-13229 has a molecular weight of 3,000 to 25,000 polyethylene glycol ether (hereinafter referred to as "PEG") 0.3 to 3.0 wt% and molecular weight 500 A method for producing by adding 0.3 to 3.0 wt% of 3,000 PEG is disclosed. The method is used for the purpose of extracting PEG to create long grooves in the fiber surface.

In addition, Japanese Laid-Open Patent Publication No. 58-120815 discloses 5-sodium sulphonic acid dimethyl ester and polyalkylene glycol ether as a method for facilitating dyeing. (Hereinafter referred to as "PAG") has been proposed to simultaneously add DMT polymerization, but this is limited to the salting of the cationic dye.

In addition, as a method of manufacturing a polyester microfiber using the prepared polymer, DuPont Korean Patent Publication No. 00188383 controls the length of the delay cooling unit from 20 to 120 mm and reduces the residence time in the spin pack to within 4 minutes. It has been suggested that a single yarn fine yarn having a single yarn fineness of 1.0 denier or less is produced. However, when actually manufactured by the above method, microfiber yarns having a single yarn fineness of 0.5 denier or less are difficult to quench and uniformly cool yarns, resulting in uneven yarn properties, in particular, poor uniformity, and an increase in radiation tension due to a decrease in single yarn fineness. There is a problem that the spinning fairness is lowered.

In addition, when increasing the number of single yarns in the same nozzle to reduce single yarn fineness, the uniformity is poor due to the cooling nonuniformity between yarns due to the increase of single yarn number, which causes a single thread or a bundle of dyed spots in the spinning process. Therefore, in the production of polyester microfibers, the uniformity of yarns is determined by the uniform cooling effect between yarns, which is an important factor in determining the quality of yarns.

However, in the conventional front unidirectional cooling method, sufficient uniform cooling is not performed, resulting in poor uniformity, poor processability due to fusion between yarns, and non-uniform properties. In order to make up for this drawback, the inventors of the present invention have known a method for maintaining the cooling between yarns evenly in Korean Patent Publication No. 004045. Specifically, the method is a method of shortening the length of the delayed cooling portion of the lower spinneret and controlling the distance between the cooling air outlet surface and the yarns shortly. The length of the delayed cooling portion is 20 mm or less, and the maximum distance between the cold air outlet surface and the yarns. 2-30 mm to improve the uniformity, processability and physical properties of the polyester microfibers.

However, polyester microfibers have a disadvantage in that they are poorly dyed in comparison with general yarns having 1 to 2 denier due to a sharp increase in surface area as single yarn fineness decreases.

Accordingly, the inventors of the present invention, in the production of polyester microfibers having a single yarn fineness of 0.1 to 0.5 denier and having a single yarn number of 70 or more, maintain the excellent physical properties of conventional polyester microfibers, and the polyester microfibers which are lightly dyed. The present invention has been completed by developing a differentiated polyester microfiber that compensates for the shortcomings.

It is an object of the present invention to provide a polyester microfine fiber having 0.1 to 0.5 deniers and single yarns of 70 or more having excellent dyeing properties and capable of deep color dyeing.

That is, the polyester microfibers excellent in dyeability of the present invention are copolymerized by mixing terephthalic acid as a main component and mixing polyalkylene glycol ethers having a number average molecular weight of 200 to 2,000 at 1 to 10% by weight with respect to the terephthalic acid. A polyester polymer was prepared by adjusting the molar ratio (G value) of the ethylene glycol ether / terephthalic acid to 1.05 to 1.15, wherein the polymer was obtained with a glass transition temperature (Tg) of 330 to 350K and a melting temperature of (Tm) of 510 to 510. It is 525K, Tm / Tg ratio satisfies 1.51-1.55, It is characterized by the intrinsic viscosity 0.5-0.7 dl / g.

In addition, the poly-polymer having excellent dyeability, characterized in that the polymer produced by melt spinning under the conditions of the length of the delayed cooling portion of the spinneret lower than 20 mm, the distance between the cold air extraction surface and thread yarn 2 mm to 30 mm or less To provide ester microfibers.

The polyester microfibers of the present invention are equally superior in physical properties such as strength (t (χ)), uniformity, and yarn strength (S) in the core of the polyester microfibers compared with the conventional ones, and particularly excellent in dyeing properties. To provide a polyester microfine fiber having a single yarn fineness of 0.1 to 0.5 denier and a single yarn number of 70 or more, which can be deeply dyed.

Looking at in detail below, the copolymer monomer of the present invention is not aromatic, but using an aliphatic copolymer monomer, more preferably polyalkylene glycol ether (PAG), an example thereof Polyethylene glycol ether (PEG), 1,2-polypropylene glycol ether, 1,3-polypropylene glycol ether, and 1,4-polybutylene glycol ether. Most preferably polyethylene glycol ether (PEG) is used.

In addition to the PAG, examples of aliphatic copolymerization monomers include α, ω-diol having 3 or more carbon atoms such as 1, 3-propanediol, 1, 4-butanediol, and the like; And diacids such as adipic acid and succinic acid, alkyl esters thereof, and acyl halides thereof. However, α, ω-diol having 3 or more carbon atoms makes it difficult to crystallize the polyester when copolymerizing, resulting in a large decrease in Tm, Seeds or derivatives thereof are not preferable because the lowering of the Tm is lower at the time of copolymerization than the α, ω-diol copolymer having 3 or more carbon atoms.

Therefore, the preferred copolymer monomer should have a small decrease in Tm, a low Tg, a block copolymer to minimize Tm, and a random copolymer to form a low Tg. do. However, when the formation of the block copolymer is too large, it becomes a segmented block copolymer (deviated from the physical properties of the conventional polyester). Thus, the polyalkylene glycol ether (PAG) is to maintain the mechanical properties of the polyester, it is not necessary to significantly lower the Tm (528K). More preferably, when the number average molecular weight of PAG is 200 to 2,000, the polyalkylene glycol ether (PAG) is glass transition temperature (Tg), 330 to 350K, melting temperature (Tm), 510 to 525K, Tm The ratio of / Tg satisfies 1.51 to 1.55. At this time, if the number average molecular weight is less than 200, the copolymer becomes a random copolymer (random copolymer), the Tm decrease is large, and if the number average molecular weight is greater than 2,000, the Tm decrease is not large, but Tg is hardly changed, which is not preferable.

The content of the polyalkylene glycol ether (PAG) is preferably 1 to 10% by weight, more preferably 3 to 7% by weight relative to terephthalic acid. At this time, if it is less than 1% by weight, the amount is too small to have a poor copolymer effect, and if it exceeds 10% by weight, the polyethylene terephthalate crystal part is dissolved in the amorphous part of the PAG regardless of the PAG molecular weight, The physical properties of are severely changed.

In addition, in the TPA polymerization method, since unreacted TPA is insoluble and non-meltable, the oligomer filter or the polymer filter of the polymerizer may be clogged, or the rate of pack pressure increase may increase during spinning. The problem that workability falls is likely to occur. Therefore, in order to solve this problem, there is a method of increasing the esterification time or increasing the esterification temperature so as to minimize the amount of unreacted TPA. However, increasing the esterification time or increasing the esterification temperature is not preferable because it increases the production of side reaction product diethylene glycol (hereinafter referred to as "DEG") to impair the thermal stability of the polymer.

Therefore, it is therefore desirable to lower the molar ratio (G value) of polyalkylene glycol ether / terephthalic acid as much as possible to inhibit DEG production. Therefore, the G value is preferably in the range of 1.05 to 1.15, and upon polymerization under these conditions, the content of DEG in the polymer is 0.7 to 1.5% by weight, and the polymer of the present invention has a glass transition temperature (Tg) of 330 to 350K. And a copolyester polymer having a melting temperature (Tm) of 510 to 525K and a Tm / Tg ratio of 1.51 to 1.55.

Therefore, using the polymer, the polyester microfiber of the present invention prepared by melt spinning can provide a microfiber improved two times more dyed than when dyed by applying a common polymer.

The polyester unstretched yarn (POY) melt-spun according to the present invention preferably exhibits physical properties satisfying the following formula.

1) t _o (χ): ≥ 1.4 g / den

t _o (χ): χ% elongation at stretch (g) ÷ yarn denier, χ is elongation at break (%) ÷ 2

t _o (χ): The strength value at the core of a polyester yarn without any additives.

2) S _o : Strength (g / den) × Elongation at Break (%) ^1/2 ≥ 30

S _o : Strong of polyester yarn with no additives,

3) Uniformity (U%) ≤ 1.2

4) Dyeability: K / S ≥ (Microfiber K / S for general polymer) × 2

In the above, K / S means the color intensity of the dye.

In addition, when the polyester unstretched yarn is drawn in a melt spinning process without undergoing a separate stretching process to prepare a polyester stretched yarn, preferably, the strength of the stretched yarn is 4.5 g / den or more and satisfies the following formula: Indicates.

1) S = strength (g / den) × elongation at break (%) ^1/2 ≥ 30

2) Uniformity (U%) ≤ 1.2

3) Dyeability: K / S ≥ (Microfiber K / S for general polymer) × 2

In the above, S means the strength of the yarn, K / S means the color strength of the dye.

The method for producing a polyester microfiber according to the present invention is composed of terephthalic acid as a main component, a polyalkylene glycol ether having a number average molecular weight of 200 to 2,000, and copolymerized by mixing 1 to 10% by weight with respect to the terephthalic acid. Preparing a polyester polymer by adjusting the molar ratio (G value) of glycol ether / terephthalic acid to 1.05 to 1.15; And melt spinning the polymer produced to have a length of the delayed cooling unit below the spinneret of 20 mm or less, and a distance between the cold air extraction surface and the yarns of 2 mm to 30 mm or less.

The melt spinning conditions shorten the length of the delayed cooling unit directly below the spinneret, and control the distance between the cold air blowout surface and the yarns to express uniform cooling between yarns. It can be seen that the yarn has a high middle strength, strength, and high strength. At this time, when the length of the spinneret directly below the delay cooling unit exceeds 20 mm, fairness and uniformity are reduced. When the distance between the cold air blowout surface and the yarn is 30 mm or more, the physical properties are uneven and the fairness is also reduced.

In addition, a polycondensation catalyst may be used in the process of producing the polyester microfiber of the present invention, and in order to utilize the fiber for clothing, an anatase type titanium dioxide may be added as in the conventional polyester.

As the polycondensation catalyst, a conventional polyester polycondensation catalyst, an antimony-based catalyst such as antimony trioxide or antimony acetate; Germanium-based catalysts; Or a titanium-based catalyst may be used. More preferably, antimony trioxide is used as the antimony-based catalyst. A preferred amount of polycondensation catalyst is 0.01 to 5% by weight relative to the polymer.

Hereinafter, the present invention will be described in more detail with reference to Examples.

This embodiment is intended to describe in detail using the most preferred embodiment of the present invention to the extent that those skilled in the art can easily carry out the technical idea of the present invention, The range is not limited to these examples.

I. Preparation of Polyester Microfiber according to Polymer

Example 1 Preparation of Polyester Microfiber 1

A slurry was prepared by mixing and stirring 1270 kg of terephthalic acid and 620 kg of ethylene glycol having 30 wt% of titanium dioxide dispersed in the polymer. At this time, the molar ratio (G value) of ethylene glycol / terephthalic acid was 1.13.

The slurry was added to an ester reactor having an ester reaction rate of 96.0% and 1.3 tons of the oligomer, which was poured into the ester reactor maintained at 260 ° C. for 4 hours to drain the theoretical amount of effluent, followed by stirring for an additional 30 minutes to produce an esterification reaction rate of 95.5 to 97.5%. The ester reaction was carried out to the range. The amount of the oligomer except 1.3 ton was transferred to the polycondensation tank, and 4 wt% of polyethylene glycol ether having a number average molecular weight of 300 was added to the polymer, and then 1 ppm by weight of antimony trioxide dissolved in ethylene glycol was 300 ppm compared to the polymer. It injected | thrown-in and it heated up at 290 degreeC of reactor temperature under vacuum. Final vacuum was set to less than 0.1 Torr. When the load on the stirrer became equal to the load on normal polyester polymerization, the vacuum was broken with nitrogen and the nitrogen was discharged. Using the polymer, spinning temperature 297 ℃, spinneret dimensions are 0.18 mm in hole diameter, 0.54 mm in hole length, and the number of thread is 192, and the discharge amount is adjusted so that the single yarn fineness of the final drawn yarn is 0.3 denier at spinning speed 2,800 m / min. Melt spinning to prepare a non-drawn yarn of polyester microfiber. At this time, the cold wind temperature was adjusted to 20 ℃, the cooling delay was installed under the spinneret, the length was adjusted to 20 mm. In addition, it was adjusted so that the maximum distance between the cold wind extraction surface and yarns was 30 mm. An undrawn yarn of the polyester microfiber prepared as described above was drawn at a draw ratio of 1.521 to prepare a drawn yarn.

<Example 2> Polyester microfiber manufacture 2

A polyester microfiber having a single yarn fineness of 0.3 denier was prepared in the same manner as in Example 1, except that the number average molecular weight of polyethylene glycol ether (PEG) used as the polyalkylene glycol ether in the polymerization process was 400. Prepared.

<Example 3> Polyester microfiber manufacture 3

A polyester microfiber having a single yarn fineness of 0.3 denier was prepared in the same manner as in Example 1, except that the number average molecular weight of polyethylene glycol ether (PEG) used as the polyalkylene glycol ether in the polymerization process was 1,000. Prepared.

<Example 4> Polyester microfiber manufacture 4

Polyester having a single yarn fineness of 0.3 denier was carried out in the same manner as in Example 1, except that the number average molecular weight of 1,2-polypropylene glycol ether used as the polyalkylene glycol ether in the polymerization process was 300. A microfiber was prepared.

<Example 5> Polyester microfiber manufacture 5

Polyester having a single yarn fineness of 0.3 denier was carried out in the same manner as in Example 1, except that the number average molecular weight of 1,3-polypropylene glycol ether used as the polyalkylene glycol ether in the polymerization process was 300. A microfiber was prepared.

Comparative Example 1

A polyester microfiber having a single yarn fineness of 0.3 denier was prepared in the same manner as in Example 1, except that the number average molecular weight of polyethylene glycol ether (PEG) used as the polyalkylene glycol ether in the polymerization process was 150. Prepared.

Comparative Example 2

A polyester microfiber having a single yarn fineness of 0.3 denier was performed in the same manner as in Example 1, except that the number average molecular weight of 1,2-polypropylene glycol used as the polyalkylene glycol ether in the polymerization process was 150. Was prepared.

Comparative Example 3

The single yarn fineness was 0.3 denier in the same manner as in Example 1, except that the number average molecular weight of poly 1,4-butylene glycol (PTMG) used as the polyalkylene glycol ether in the polymerization process was 4,000. The polyester microfiber of the was prepared.

<Comparative Example 4>

A polyester microfiber having a single yarn fineness of 0.3 denier was prepared in the same manner as in Example 1, except that a general polyester polymer having an intrinsic viscosity of 0.63 was used.

Experimental Example 1

Physical properties and dyeability of the polyester microfiber of 0.3 single fineness fineness 0.3 prepared in Examples 1 to 3 to Comparative Examples 1 to 3 were tested.

1: strength (g / den) measurement

The strength was determined by the strength ÷ yarn denier at break elongation. In addition, S is a function of the yarn's strength, and is represented by strength (g / den) x elongation at break (%) ^1/2 . Each physical property was measured 30 times to determine the average value thereof.

2: measurement of uniformity (U%)

The measured value obtained using the Uster% measuring instrument was quantified by the CV% of the yarn weight per 10 cm in unit length.

3. Dyeability measurement

After preparing the sample by knitting the yarn prepared in the above Examples and Comparative Examples to a length of 20 cm with a circular knitting machine, put it in a salt bath, dyeing temperature, constant temperature rising to 1 ℃ / min in the range of 30 ~ 130 ℃ 30 to 30 ℃ Staining was maintained for a minute. After the dyeing sample was sufficiently dried, a white plate was placed to visually determine dyeability. At this time, the salt bath was prepared by dispersing dye Koh-navy (S-type) with a dye concentration of 1% o.w.f., 1g / L of a dispersant (VGT), pH 4.5 ~ 5.5 (acetic acid), a liquid ratio of 1 to 15. The evaluation method of the dyeability was carried out a sensory experiment in which the dye is uniformly stained with concentrated salt, "○", usually "△", and when it is lightly dyed or unevenly dyed "x".

In addition, the color intensity of the dye was measured K / S maximum value using a spectrophotometer (spectrophotometer). At this time, as the K / S maximum value was higher, the dyed paper was observed in a darker color.

4. Measurement of the ultimate viscosity (IV) :

A solution mixed with 60/40 weight ratio of phenol and 1, 1, 2, 2-tetrachloroethane was measured at 30 ° C. using a Ubbelohde viscometer.

5. Determination of DEG content :

The prepared polymer was hydrolyzed with monoethanolamine and analyzed by gas chromatography (GC).

6. Melt temperature (Tm) and glass transition temperature (Tg) measurement :

Using a product of Perkin Elmer (model name DSC 7), the temperature was raised to 10 ° C / min and the peak in the melting range was analyzed. Table 1 shows the experimental results.

division Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Comparative Example 3 PAG Type PEG PEG PEG PEG PTMG General Polyester Polymer PAG number average molecular weight 300 400 1,000 150 4,000 PAG content (% by weight) 4 4 4 4 4 DEG content (% by weight) 1.3 1.4 1.2 0.95 1.5 0.9 Glass transition temperature (K) 339.7 341.4 344.7 338.2 337.9 350.3 Melting temperature (K) 521.0 522.8 525.8 520.9 527.2 526.8 Tm / Tg 1.534 1.529 1.525 1.540 1.560 1.504 △ H _f 40.5 39.6 40.8 34.8 49.6 44.3 Titanium Dioxide (wt%) 0.3 0.03 0.3 0.3 0.3 0.3 Cinnabar island 0.3 Strength (g / d) 4.8 4.7 4.6 4.5 4.3 4.7 S 33.6 32.9 32.1 29.5 30.1 33.5 Uniformity (U%) 1.1 1.0 1.0 1.1 1.2 1.0 Dyeability ○ ○ ○ × × ○ K / S maximum value 11.2 10.5 10.1 7.5 6.5 5.0

PTMG: Poly 1,4-butylene glycol

* ΔH _f represents melt enthalpy

* The higher K / S value, the darker the color of dyed paper.

As shown in Table 1, the polyester microfine yarn of 0.3 single yarn fineness manufactured in Examples 1 to 3 of the present invention, when compared with the microfine yarn of the same single yarn fineness of Comparative Examples 1 to 3, the strength, yarn While maintaining the excellent physical properties such as strength (S), the leveling agent, and more excellent results compared to the conventional one for the dyeing of thick salt.

II. Preparation of polyester microfiber according to melt spinning conditions

<Example 6> Polyester microfiber manufacture 6

The polymer prepared above was carried out as follows for the preferable conditions for the production of polyester microfibers with low single yarn fineness. Thus, using the polymer prepared in Example 1 spinning temperature 297 ℃, spinneret dimensions are 0.18 mm hole diameter, 0.54 mm hole length and the number of thread number is 192 pieces by adjusting the discharge amount so that the single yarn fineness of the final drawn yarn is 0.2 denier Melt spinning was performed at a spinning speed of 2,800 m / min. At this time, the cold wind temperature was adjusted to 20 ℃, the cooling delay unit was installed directly under the spinneret and its length was adjusted to 5 mm. In addition, the maximum distance between the cold wind extraction surface and the thread yarn was adjusted to 30 mm to prepare an undrawn yarn of polyester microfiber, and to be drawn at a draw ratio of 1.521 to prepare a drawn yarn.

<Example 7> Polyester microfiber manufacture 7

The single yarn fineness of the final stretched yarn was 0.3 denier, the length of the delayed cooling portion was 20 mm, and the maximum distance between the cold wind extraction surface and the yarns was adjusted to 20 mm. Undrawn yarn of a polyester microfiber was prepared, and drawn at a draw ratio of 1.521 to prepare a drawn yarn.

Comparative Example 5

The single yarn fineness of the final stretched yarn was carried out in the same manner as in Example 1 except that the single yarn fineness of 0.5 denier, the length of the delayed cooling portion was adjusted to 30 mm, and the maximum distance between the cold wind extraction surface and the yarns were adjusted to 20 mm. Undrawn yarn of a polyester microfiber was prepared, and drawn at a draw ratio of 1.521 to prepare a drawn yarn.

Comparative Example 6

The single yarn fineness of the final stretched yarn was 0.3 denier, the length of the delay cooling part was adjusted to 30 mm, and the maximum distance between the cold air extraction surface and the yarn was adjusted to 20 mm, except that the single yarn fineness was 0.3. Undrawn yarn of a polyester microfiber was prepared, and drawn at a draw ratio of 1.521 to prepare a drawn yarn.

Comparative Example 7

The single yarn fineness of the final stretched yarn was 0.5 denier, the length of the delayed cooling portion was 60 mm, and the maximum distance between the cold wind extraction surface and the yarns was adjusted to 20 mm. Undrawn yarn of a polyester microfiber was prepared, and drawn at a draw ratio of 1.521 to prepare a drawn yarn.

<Comparative Example 8>

The single yarn fineness of the final stretched yarn was 0.5 denier, the length of the delayed cooling portion was 20 mm, and the maximum distance between the cold air extraction surface and the yarns was adjusted to 40 mm. Undrawn yarn of a polyester microfiber was prepared, and drawn at a draw ratio of 1.521 to prepare a drawn yarn.

Comparative Example 9

The single yarn fineness of the final stretched yarn was carried out in the same manner as in Example 1, except that 0.5 denier of the final stretched yarn, the length of the delayed cooling portion was 20 mm, and the maximum distance between the cold air extraction surface and the yarns were adjusted to 120 mm. Undrawn yarn of a polyester microfiber was prepared, and drawn at a draw ratio of 1.521 to prepare a drawn yarn.

Comparative Example 10

The single yarn fineness of the final stretched yarn was carried out in the same manner as in Example 1 except that the single yarn fineness of the final stretched yarn was 0.5 denier, the length of the delayed cooling portion was 30 mm, and the maximum distance between the cold air extraction surface and the yarns was adjusted to 120 mm. Undrawn yarn of a polyester microfiber was prepared, and drawn at a draw ratio of 1.521 to prepare a drawn yarn.

Experimental Example 2

Physical properties, spinning process evaluation and dyeing properties of the undrawn and drawn yarns of the polyester microfibers prepared in Examples 4 to 5 and Comparative Examples 4 to 9 were measured in the same manner as in Experimental Example 1, and are shown in Table 2 below. In this case, t (χ) means strength at the middle body, strength (g) ÷ yarn denier at the time of χ% stretching, χ was calculated as elongation at break (%) ÷ 2.

division Example 4 Example 5 Comparative Example 4 Comparative Example 5 Comparative Example 6 Comparative Example 7 Comparative Example 8 Comparative Example 9 Shrine Shrine Fine yarn (den / fila) 0.2 0.3 0.5 0.3 0.5 0.5 0.5 0.5 Hot Zone Length (mm) 5 20 30 30 60 20 20 30 Distance between cold air extraction surface and thread (mm) 30 20 20 20 20 40 120 120 Unpainted Shrine t (χ) 1.76 1.59 1.31 1.22 1.15 1.29 1.03 - S 38.1 35.5 27.3 25.9 23.6 28.1 22.5 - Uniformity (U%) 0.82 1.06 1.41 1.55 2.26 1.63 2.05 - Drawing company Strength (g / den) 4.7 4.8 4.1 4.2 3.9 4.1 3.7 - S 36.5 33.6 26.1 24.8 23.2 27.5 22.1 - Uniformity (U%) 0.91 1.10 1.56 1.54 2.31 1.72 2.21 - Radiation fairness ○ ○ × × × × × ×× Dyeability ○ ○ × × × △ × -

As shown in Table 2, the length of the delay zone of the spinneret under the spinneret, which is the melt spinning condition of the present invention, is 20 mm or less, and the distance between the cold air extraction surface and the yarns is in the range of 2 mm to 30 mm or less. Polyester unstretched yarn (POY) prepared by performing and stretching the unstretched yarn at an appropriate draw ratio, or polyester drawn yarn prepared in a spinning process without a separate stretching process, the strength (t (χ)), , Physical properties such as yarn strength (S) was excellent, in particular, excellent spinning processability and dyeing. Therefore, the polyester microfiber of the present invention using the same overcomes the problems of conventional deep color development.

As described above, the present invention is a differentiated polyester microfine fiber capable of deep color dyeing with excellent dyeability while maintaining the physical properties equivalent to those of conventional polyester microfibers of 0.1 to 0.5 denier and 70 or more conventional yarns. Provided.

Although the present invention has been described in detail only with respect to the described embodiments, it will be apparent to those skilled in the art that various modifications and variations are possible within the technical scope of the present invention, and such modifications and modifications are within the scope of the appended claims.

Claims (6)

In polyester microfibers having a single yarn fineness of 0.1 to 0.5 denier and a single yarn number of 70 or more produced by terephthalic acid polymerization (TPA polymerization method), the terephthalic acid is a main component and has a number average molecular weight of 200 to 2,000 polyalkylene glycol ether To the terephthalic acid by mixing in 1 to 10% by weight, copolymerization, and adjusted the molar ratio (G value) of polyalkylene glycol ether / terephthalic acid to 1.05 to 1.15 to prepare a polyester polymer, and to spin the polymer produced A fine polyester fiber having excellent dyeability, characterized in that it is manufactured by melt spinning the length of the delayed cooling portion of the lower part of the mold to 20 mm or less, and the distance between the cold air extraction surface and the yarns of 2 mm to 30 mm or less. The polymerized product according to claim 1, wherein the polymer has a glass transition temperature (Tg) of 330 to 350K, a melting temperature of Tm of 510 to 525K, and a ratio of Tm / Tg of 1.51 to 1.55, and an intrinsic viscosity of 0.5 to 0.7. It is dl / g, The polyester microfine fiber excellent in the said dyeability. The polyalkylene glycol ether according to claim 1, wherein the polyalkylene glycol ether is any one selected from the group consisting of polyethylene glycol ether, 1,2-polypropylene glycol ether, 1,3-polypropylene glycol ether, and 1,4-polybutylene glycol ether The polyester microfine fiber excellent in the said dyeability characterized by the above-mentioned. 4. The polyester microfine fiber having excellent dyeability according to claim 3, wherein the polyalkylene glycol ether is polyethylene glycol ether. The polyester microfiber excellent in the dyeability according to claim 1, wherein the unstretched physical properties of the polyester microfiber satisfy the following formula. 1) t _o (χ): ≥ 1.4 g / den t _o (χ): χ% strength at stretch (g) 데 yarn denier, χ is elongation at break (%) ÷ 2 t _o (χ): The strength value at the core of a polyester yarn without any additives. 2) S _o : Strength (g / den) × Elongation at Break (%) ^1/2 ≥ 30 S _o : Strong of polyester yarn with no additives, 3) Uniformity (U%) ≤ 1.2 4) Dyeability: K / S ≥ (Microfiber K / S for general polymer) × 2 In the above, K / S means the color intensity of the dye. The polyester microfiber having excellent dyeing properties according to claim 1, wherein the stretched yarn physical properties of the polyester microfiber satisfy the following formula. 1) Strength ≥ 4.5g / den 2) S: Strength (g / den) 신 Elongation at Break (%) ^1/2 ≥ 30 3) Uniformity (U%) ≤ 1.2 4) Dyeability: K / S ≥ (Microfiber K / S for general polymer) × 2 In the above S means the strength of the yarn, K / S means the color strength of the dye.