JP5180766B2 - Hollow polyester fiber and method for producing the same - Google Patents

Description

  The present invention is a hollow normal pressure cationic dyeable polyester fiber suitable for sports clothing and the like, which is excellent in lightness and dyeable to a cationic dye under normal pressure, and can increase the tearing strength of a fabric, and the like It relates to a manufacturing method.

  Polyester fibers have various excellent properties including mechanical properties, and are used in various applications and fields including clothing. However, it has a feature that it feels harder than natural fibers. Therefore, recently, in order to improve the functionality of the polyester fiber, the lightness and the deep color have been improved by changing the cross-sectional shape of the polyester fiber or modifying the polymer. Especially for sports apparel, further lightness and fabric strength have been required.

In order to express its lightness, the spinneret has a hollow shape and maintains a high hollow ratio, thereby increasing its lightness or adding a polyvinyl alcohol-based resin to the center with a composite fiber. Various methods have been proposed in which the resin is eluted, the substantial hollow ratio of the polyester fiber is increased, and lightness is expressed. (For example, see Patent Document 1)
For deep color, a method of copolymerizing a metal salt of sulfoisophthalic acid with 2 to 3 mol% of polyester has been proposed (see, for example, Patent Documents 2 and 3).

  However, the polyester fiber obtained by such a method can be dyed only under high temperature and high pressure, and if it is dyed after knitting or weaving with natural fiber or urethane fiber, natural fiber and urethane fiber are embrittled. There was a problem. If this is to be sufficiently dyed at normal pressure and at a temperature around 100 ° C., it is necessary to copolymerize a large amount of the metal salt of sulfoisophthalic acid. In this case, from the thickening effect due to the sulfonate group, There is a problem that the degree of polymerization of the polyester cannot be increased, the strength of the polyester fiber obtained by melt spinning is remarkably lowered, and the spinning operability is remarkably deteriorated.

  On the other hand, in order to solve such a problem, a technique for copolymerizing a cationic dyeable monomer having a small ion-binding intermolecular force has been disclosed (for example, see Patent Documents 4 and 5). Examples of cationic dyeable monomers having a small ion-binding intermolecular force include 5-sulfoisophthalic acid tetrabutoxyphosphonate and the like, but these cationic dyeable monomer copolymer polyesters have poor thermal stability, and are used as atmospheric pressure cations. Even if an attempt was made to increase the amount of copolymerization for dyeing, thermal decomposition progressed during the polymerization reaction, making it difficult to increase the molecular weight. Furthermore, there is a drawback that the decomposition due to the thermal history during melt spinning is large, and the strength of the resulting yarn is weakened. Further, the 5-sulfoisophthalic acid tetrabutoxyphosphonate used is very expensive, and there is a problem that the cost of the resulting cationic dyeable polyester is greatly increased.

  As a method for solving such a problem, in addition to a metal salt of sulfoisophthalic acid, a method of copolymerizing polyethylene glycol having a molecular weight of 2000 or more, a method of copolymerizing a dicarboxylic acid of a linear hydrocarbon such as adipic acid or sebacic acid, Alternatively, a method of copolymerizing glycol components such as diethylene glycol, neopentyl glycol, and cyclohexanedimethanol has been proposed. (For example, see Patent Documents 6 and 7)

  On the other hand, as a method for producing a low pressure resistance decrease and normal pressure dyeability, linear hydrocarbon dicarboxylic acids such as adipic acid and sebacic acid, or glycol components such as diethylene glycol, neopentyl glycol, and cyclohexanedimethanol In addition, a method of copolymerizing a polyalkylene glycol having an average molecular weight of 400 to 1000 with a metal salt of sulfoisophthalic acid has been proposed (for example, see Patent Document 8).

  However, the strength of the atmospheric pressure cationic dyeable polyester fiber obtained by melt spinning the polyester obtained by any of these methods is lowered, and thus the tear strength of the resulting fabric is lowered, and further the dyeing fastness is increased. There was a problem such as low.

  Further, there has been proposed a composite fiber in which a polyester copolymerized with 5-sodium sulfoisophthalic acid is disposed in the sheath portion and a polyester having 95 mol% or more of ethylene terephthalate repeating units disposed in the core portion (see, for example, Patent Document 9). ). However, the copolymerization amount of the sulfoisophthalic acid component in the copolyester constituting the sheath part is limited for the same reason as described above, and it is difficult to obtain sufficient dyeing properties. As a result, there are problems such as an increase in processing cost in the spinning process or a restriction on the fiber cross-sectional shape.

Japanese Patent Laid-Open No. 10-96136 Japanese Patent Publication No.34-10497 JP-A-62-89725 JP-A-1-162822 JP 2006-176628 A JP 2002-284863 A JP 2006-200064 A JP 2002-284863 A Japanese Patent Laid-Open No. 7-126920

  The present invention solves the above-mentioned problems, and relates to a hollow polyester fiber having an excellent lightness and being dyeable to a cationic dye under normal pressure. The present invention relates to a normal pressure cationic dyeable hollow cross-section multifilament suitable for sports clothing and the like that can improve the tear strength of a fabric while having a texture and excellent deep color.

［上記式中、Ｒは水素または炭素数１〜１０のアルキル基を表し、Ｘは４級ホスホニウム塩、または４級アンモニウム塩を表す。］
４．０≦Ａ＋Ｂ≦５．０ （数式１）
０．２≦Ｂ／（Ａ＋Ｂ）≦０．７ （数式２）
［ここで、Ａはスルホイソフタル酸の金属塩の共重合量（モル％）、Ｂは上記化学式（１）で表される化合物の共重合量（モル％）を表す。］ In view of the above problems, the present inventors have intensively studied, and as a result, have completed the present invention.
That is, according to the present invention,
A normal pressure cationic dyeable hollow polyester fiber which is a polyester composed of ethylene terephthalate as a main repeating unit and satisfies the following requirements.
a) In the acid component constituting the polyester, the metal salt of sulfoisophthalic acid (A) and the compound (B) represented by the following chemical formula (1) satisfy the following formulas (1) and (2) at the same time. Contain under conditions to do.
b) The diethylene glycol content in the polyester is 2.5% by weight or less.
c) The intrinsic viscosity of the polyester is 0.55 to 1.0.
d) The hollow ratio of the single yarn is 5 to 80%.

[In the above formula, R represents hydrogen or an alkyl group having 1 to 10 carbon atoms, and X represents a quaternary phosphonium salt or a quaternary ammonium salt. ]
4.0 ≦ A + B ≦ 5.0 (Formula 1)
0.2 ≦ B / (A + B) ≦ 0.7 (Formula 2)
[Here, A represents the copolymerization amount (mol%) of the metal salt of sulfoisophthalic acid, and B represents the copolymerization amount (mol%) of the compound represented by the chemical formula (1). ]

  According to the present invention, it is possible to provide a polyester fiber having excellent lightness, good color tone, and good dyeing property by cationic dyeing under normal pressure.

Hereinafter, the present invention will be described in detail.
In the polyester hollow cross-section fiber of the present invention, the cross-sectional shape of the single yarn is hollow, and the hollow ratio is 5 to 80%, preferably 10 to 60%, more preferably 20 to 40%.
The cross-sectional shape of the hollow cross-section fiber of the present invention represents a polyester fiber forming a hollow section having a round cross section or three or more polygonal cross-section shapes. Further, the number of hollow portions is not limited to one, and may be hollow fibers having two or more hollow portions. Further, the shape of the entire fiber is not limited to a round cross section, and may be a polygonal cross section shape of three or more. Further, the shape of the entire fiber is not limited to a round cross section, and may be a polygonal cross section shape of three or more, and has a recess in the cross section within a range that does not affect the formation of a hollow. An irregular cross section may be used. Further, the fineness of the hollow fiber is not particularly limited, but is 10 to 300 dtex, preferably 30 to 200 dtex, and the single yarn fineness is 0.3 to 5.0 dtex, preferably from the viewpoint of yarn-making property and deep color. 0.5 to 3.0 dtex.

  The polyester used in the present invention is a polyester having ethylene terephthalate as a main repeating unit obtained by polycondensation reaction of terephthalic acid or an ester-forming derivative thereof and an ethylene glycol component. A copolymer polyester containing a metal salt of sulfoisophthalic acid (A) and a compound (B) represented by the following chemical formula (1) in a state satisfying the following mathematical formulas 1 and 2 at the same time, and diethylene glycol in the polyester The content is 2.5% by weight or less, the intrinsic viscosity is 0.55 to 1.0, and the cross-sectional shape of the fiber obtained thereby is a flat shape, and the flat shape is a round cross-section single yarn in the longitudinal direction. It is a normal pressure cationic dyeable polyester fiber characterized by having a flat cross-section having a shape such that 3 to 6 are joined.

［上記式中、Ｒは水素または炭素数１〜１０のアルキル基を表し、Ｘは４級ホスホニウム塩、または４級アンモニウム塩を表す。］
４．０≦Ａ＋Ｂ≦５．０ （数式１）
０．２≦Ｂ／（Ａ＋Ｂ）≦０．７ （数式２）
［ここで、Ａはスルホイソフタル酸の金属塩の共重合量（モル％）、Ｂは上記化学式（１）で表される化合物の共重合量（モル％）を表す。］

[In the above formula, R represents hydrogen or an alkyl group having 1 to 10 carbon atoms, and X represents a quaternary phosphonium salt or a quaternary ammonium salt. ]
4.0 ≦ A + B ≦ 5.0 (Formula 1)
0.2 ≦ B / (A + B) ≦ 0.7 (Formula 2)
[Here, A represents the copolymerization amount (mol%) of the metal salt of sulfoisophthalic acid, and B represents the copolymerization amount (mol%) of the compound represented by the chemical formula (1). ]

(Description of component A)
Examples of the sulfonate group-containing aromatic dicarboxylic acid component used in the present invention include a metal salt of 5-sulfoisophthalic acid (sodium salt, lithium salt, potassium salt), a quaternary phosphonium salt of 5-sulfoisophthalic acid, or 5 -Quaternary ammonium salts of sulfoisophthalic acid are exemplified. These ester-forming derivatives are also preferably exemplified. Among these groups, a metal salt of 5-sulfoisophthalic acid is preferably exemplified from the viewpoint of thermal stability, cost, etc., and in particular, a sodium salt of 5-sulfoisophthalic acid and a dimethyl ester thereof, 5-sulfoisophthalic acid. Particularly preferred is the sodium salt of dimethyl acid.

(Description of component B)
The compound (B) represented by the chemical formula (1) is quaternary phosphonium salt or quaternary ammonium salt of 5-sulfoisophthalic acid or its lower alkyl ester. As the quaternary phosphonium salt, the quaternary ammonium salt is preferably a quaternary phosphonium salt or a quaternary ammonium salt substituted with an alkyl group, a benzyl group or a phenyl group, and particularly preferably a quaternary phosphonium salt. The four substituents may be the same or different. Specific examples of the compound represented by the chemical formula (1) include 5-sulfoisophthalic acid tetrabutylphosphonium salt, 5-sulfoisophthalic acid ethyltributylphosphonium salt, 5-sulfoisophthalic acid benzyltributylphosphonium salt, and 5-sulfoisophthalic acid. Acid phenyltributylphosphonium salt, 5-sulfoisophthalic acid tetraphenylphosphonium salt, 5-sulfoisophthalic acid butyltriphenylphosphonium salt, 5-sulfoisophthalic acid benzyltriphenylphosphonium salt, or dimethyl ester or diethyl ester of these isophthalic acid derivatives Preferably exemplified.

(Explanation of Formula 1)
In the present invention, the total of component A and component B copolymerized with polyester needs to be within a range of 4.0 to 5.0 mol% of A + B based on the acid component. If it is less than 4.0 mol%, sufficient dyeing cannot be obtained by cationic dyeing under normal pressure. On the other hand, if it exceeds 5.0 mol%, the strength of the resulting polyester yarn is lowered, which is not suitable for practical use. Further, since the dye is consumed excessively, it is disadvantageous in terms of cost.

(Explanation of Formula 2)
The component ratio between component A and component B must be such that B / (A + B) is in the range of 0.2 to 0.7. When the ratio is 0.2 or less, that is, in a state where the proportion of component A is large, it is difficult to increase the degree of polymerization of the resulting polyester due to the thickening effect of the metal salt of sulfoisophthalic acid. On the other hand, when the ratio is 0.7 or more, that is, the ratio of the component B is large, the reaction is slow, and when the ratio of the component B is further increased, the decomposition proceeds and the degree of polymerization cannot be increased. Further, when the ratio of component B is increased, the thermal stability is deteriorated, and the decrease in molecular weight due to thermal decomposition when remelted in the melt spinning stage is increased, so that the strength of the resulting polyester yarn is decreased, which is not preferable.

(Description of DEG amount)
The diethylene glycol contained in the normal pressure cationic dyeable polyester in the present invention is preferably 2.5% by weight or less.
In general, when a cationic dyeable polyester is produced, in order to suppress the amount of diethylene glycol (DEG) by-produced in the production process of the polyester, a small amount of alkali metal salt, alkaline earth metal salt, hydroxide is used as a DEG inhibitor. 1 to 20 mol of the cationic dyeable monomer (compounds (A) and (B) in the case of the present invention) at least one of tetraalkylphosphonium, tetraalkylammonium hydroxide, trialkylamine and the like used. It is preferable to add about%.

(Explanation of intrinsic viscosity)
The intrinsic viscosity (solvent: orthochlorophenol, measurement temperature: 35 ° C.) of the polyester used in the present invention is preferably in the range of 0.55 to 1.0. When the intrinsic viscosity is 0.55 or less, the resulting polyester fiber is insufficient in strength and the hollowness is lowered due to insufficient melt viscosity. On the other hand, when it is 1.0 or more, the melt viscosity becomes too high and melt molding occurs. It is not preferable because it becomes difficult, and it is not preferable because the production cost in the polycondensation step of the polymerized polyester greatly increases by the solid phase polymerization method following the melt polymerization method. The intrinsic viscosity of the normal pressure cationic dyeable polyester is more preferably in the range of 0.60 to 0.90.

(Production method of polyester)
The production of the copolyester in the present invention is not particularly limited, and a conventionally known polyester production method is used. That is, a low polymer is produced by a direct polycondensation reaction between terephthalic acid and ethylene glycol, or an ester exchange reaction between an ester-forming derivative of terephthalic acid typified by dimethyl terephthalate and ethylene glycol. Subsequently, this reactive organism is produced by heating under reduced pressure in the presence of a polycondensation catalyst to carry out a polycondensation reaction until a predetermined polymerization degree is reached. As a method for copolymerizing an aromatic dicarboxylic acid containing sulfoisophthalic acid and / or an ester derivative thereof, a generally known production method can be used.

(Other additives)
In addition, the copolymer polyester in the present invention contains a small amount of additives as necessary, for example, antioxidants, fluorescent whitening agents, antistatic agents, antibacterial agents, ultraviolet absorbers, light stabilizers, heat stabilizers, and light-shielding agents. Or it may contain a matting agent. In particular, antioxidants and matting agents are particularly preferably added.

(Melt spinning)
There is no restriction | limiting in particular in the polyester yarn manufacturing method in this invention, A conventionally well-known method is employ | adopted. That is, it is preferable to produce the dried copolyester by melt spinning at a temperature in the range of 270 ° C. to 300 ° C., and the spinning speed of the melt spinning is preferably 400 to 5000 m / min. When the spinning speed is within this range, the strength of the obtained fiber is sufficient, and the winding can be stably performed. Furthermore, it is preferable that the undrawn yarn or the partially drawn yarn obtained by the above method is drawn in a range of about 1.2 times to 6.0 times in the drawing step. This stretching may be performed after winding the unstretched polyester fiber once, or may be performed continuously without winding.

Hereinafter, the present invention will be described more specifically with reference to examples. The present invention is not limited to these examples. Each item in the examples was measured by the following method.
(1) A dilute solution in which the intrinsic viscosity polyester composition was dissolved in orthochlorophenol at 100 ° C. for 60 minutes was determined from the value measured at 35 ° C. using an Ubbelohde viscometer. The intrinsic viscosity of the tip is ηC, and the intrinsic viscosity of the undrawn yarn after spinning is ηF.
(2) Diethylene glycol (DEG) content:
The polyester composition chip was decomposed using hydrazine hydrate (hydrated hydrazine), and the content of diethylene glycol in the decomposition product was measured using gas chromatography (HP Hewlett-Packard (HP 6850)).
(3) Tensile strength / elongation of fiber Measured according to the method described in JIS L1070.
(4) Cationic dyeable CATHILON BLUE CD-FRLH) 0.2 g / L, CD-FBLH 0.2 g / L (both Hodogaya Chemical), sodium sulfate 3 g / L, acetic acid 0.3 g / L And dyed at a bath ratio of 1:50 at 100 ° C. for 1 hour, and the dyeing rate was determined by the following formula.
Dyeing rate = (OD0−OD1) / OD0
OD0: Absorbance at 576 nm of the dye solution before dyeing
OD1: Absorbance at 576 nm of the dyeing solution after dyeing In the present invention, a dyeing rate of 98% or more was judged as good dyeability.

[Example 1]
In a mixture of 100 parts by weight of dimethyl terephthalate and dimethyl 5-sodium sulfoisophthalate and 60 parts by weight of ethylene glycol as shown in Table 1, 0.03 parts by weight of manganese acetate and 0.12 parts by weight of sodium acetate trihydrate Was added, and the ester exchange reaction was carried out while gradually raising the temperature from 140 ° C. to 240 ° C. while distilling methanol produced as a result of the reaction out of the system. Thereafter, 0.03 part by weight of normal phosphoric acid was added to complete the transesterification reaction.
Thereafter, the reaction product of antimony trioxide and 0.05 parts by weight and the Table 1 amount to become 5-sulfoisophthalate, 0.3 part by weight of phthalic acid tetrabutoxy phosphonate with tetraethylammonium hydroxide and triethylamine 0.003 parts by weight was added Transferred to a polymerization vessel, heated to 285 ° C., and subjected to a polycondensation reaction at a high vacuum of 30 Pa or less, and the reaction was terminated when the agitator power of the polymerization tank reached a predetermined power or a predetermined time passed, Chips were made according to conventional methods.
This polyethylene terephthalate chip was spun at a spinning temperature of 290 ° C. from a spinneret having 36 discharge holes having a concentric double round single yarn cross-sectional shape, applied with an oil agent, and taken up at a spinning speed of 3000 m / min. After that, a multifilament made of the hollow cross-section fiber of the present invention having a preheating temperature of 85 ° C., a heat setting temperature of 120 ° C., a draw ratio of 1.7, and a speed of 800 m / min, and having a single fineness of 2.4 dtex and a total fineness of 84 dtex is obtained. Obtained. The obtained multifilament was woven at a weaving density of 110 yarns / 2.54 cm and untwisted to make a plain woven fabric, then dyed according to a conventional method, and the obtained fabric was evaluated by each of the above methods. went. The results are shown in Table 1.

[Examples 2 to 3 and Comparative Examples 1 to 4]
In Example 1, it implemented like Example 1 except having changed the addition amount of sodium 5-sulfoisophthalate and 5-sulfoisophthalate tetrabutylphosphonate so that it might become Table 1. FIG.

[Comparative Example 5]
In Example 3, it was carried out in the same manner as in Example 3 except that the stirring power in the polycondensation reaction is the completion of the reaction at a lower stage.

[Comparative Example 6]
In Example 3, sodium acetate trihydrate, tetraethylammonium hydroxide, except that no triethylamine was added was prepared as in Example 3.

  According to the present invention, it is suitable for sports clothing and the like as an atmospheric pressure cationic dyeable hollow fiber having excellent lightness, excellent deep color and high tear strength of the fabric.

The schematic diagram of the single yarn cross section of the polyester hollow cross-section fiber in this invention is shown.

Claims (3)

A normal pressure cationic dyeable hollow polyester fiber which is a polyester composed of ethylene terephthalate as a main repeating unit and satisfies the following requirements.
a) In the acid component constituting the polyester, the metal salt of sulfoisophthalic acid (A) and the compound (B) represented by the following chemical formula (1) satisfy the following formulas (1) and (2) at the same time. Contain under conditions to do.
b) The diethylene glycol content in the polyester is 2.5% by weight or less.
c) The intrinsic viscosity of the polyester is 0.55 to 1.0.
d) The hollow ratio of the single yarn is 5 to 80%.

[In the above formula, R represents hydrogen or an alkyl group having 1 to 10 carbon atoms, and X represents a quaternary phosphonium salt or a quaternary ammonium salt. ]
4.0 ≦ A + B ≦ 5.0 (Formula 1)
0.2 ≦ B / (A + B) ≦ 0.7 (Formula 2)
[Here, A represents the copolymerization amount (mol%) of the metal salt of sulfoisophthalic acid, and B represents the copolymerization amount (mol%) of the compound represented by the chemical formula (1). ]   2. The atmospheric pressure cationic dyeable polyester fiber according to claim 1, wherein the metal salt of sulfoisophthalic acid is 5-sodium sulfoisophthalic acid.   The atmospheric pressure cationic dyeable polyester fiber according to claim 1, wherein the compound (B) is 5-sulfoisophthalic acid tetrabutylphosphonate.

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