JP2009227914A - Polyester, polyester fiber and polyester fiber product - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a polyester, and fibers and fiber products made of the polyester, which are particularly solid-core fibers of a single component and to which high antistatic property and whitening resistance can be imparted. <P>SOLUTION: The polyester comprises ethylene terephthalate as a main repeating unit, to which a diol component expressed by general formula (1) is copolymerized by 1.0 to 10.0 mass% with respect to the whole polyester mass, and a sulfoisophthalate is copolymerized by 0.2 to 1.0 mol% to terephthalic acid constituting the polyethylene terephthalate. In the above formula, R represents a 1C-18C hydrocarbon group and n represents a natural number of 40 to 150. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to polyester and fibers and textiles comprising the same. More specifically, the present invention relates to a polyester composition that is excellent in antistatic properties, particularly in a single-component solid fiber, and has both antistatic properties and whitening resistance, and a fiber and a fiber product comprising the same.

  Polyesters, especially polyethylene terephthalate, polyethylene naphthalate, polytrimethylene terephthalate and polytetramethylene terephthalate are widely used in fibers, films or other molded products because of their excellent mechanical, physical and chemical performance. Yes. Among them, polyethylene terephthalate is particularly excellent in mechanical properties, chemical properties, moldability, etc., and has been used for polyester fibers for a long time. However, since polyester is hydrophobic, its use in fields where antistatic properties are required is limited.

  In order to meet such demands, attempts have been made to impart antistaticity by imparting hydrophilicity to polyester, and many proposals have been made so far. For example, as one of attempts to impart antistatic properties to polyester fibers, a method of blending polyoxyalkylene glycol with polyester is known (for example, see Patent Document 1). However, in order to exhibit sufficient antistatic properties to the polyester fiber by this method, a large amount of 15 to 20% by weight of polyoxyalkylene glycol is required, and the obtained antistatic polyester fiber has physical properties, particularly thermal properties. It is greatly reduced and inferior in washing fastness, so it cannot be used.

  In order to eliminate such drawbacks, for example, a polyester having a small amount (about 5% or less) of an antistatic agent composed of polyoxyalkylene glycol and a sulfonic acid metal salt is melt-spun into a hollow fiber. Has proposed a method in which most of the antistatic agent is coagulated and localized around the fiber hollow portion (see, for example, Patent Document 2). However, since the fiber obtained by this method is a hollow fiber, its use has been limited.

  On the other hand, although a method for localizing the antistatic agent at a high concentration in the core portion of the core-sheath composite fiber has been proposed (see, for example, Patent Documents 3 to 5), the yarn-making cost increases because it is a composite fiber. In addition, there has been a drawback that it is difficult to produce ultrafine fibers, which has been attracting attention in recent years.

In addition, instead of the water-soluble polyoxyethylene glycol generally used in conventional antistatic polyester fibers, polyoxyethylene-based polyoxyethylene-based polymers made water-free by copolymerizing ethylene oxide with a specific higher olefin oxide. It has been proposed to solve the above problems by using ether (see, for example, Patent Documents 6 to 8).
However, in this method, the water-insolubilized polyoxyethylene-based polyether used is expensive and the antistatic property of the resulting fiber is not sufficient.

  Further, these antistatic fibers and fiber products have a great disadvantage that fine fibrils are easily generated during yarn processing and the fabric is whitened. Antistatic fibers are expected to be applied to winter clothing that is prone to static electricity.However, since winter clothing is generally preferred to dark colors, it cannot be applied to conventional whitening antistatic fibers, and is resistant to whitening. There has been a demand for the development of a fiber having both antistatic properties.

Japanese Examined Patent Publication No. 39-05214 Japanese Patent Publication No. 60-56802 Japanese Patent Publication No. 61-06883 Japanese Patent Laid-Open No. 55-122020 JP-A 61-28016 JP-A-3-139556 JP 2002-309486 A JP 2003-129336 A

  An object of the present invention is to provide a polyester, a fiber comprising the same, and a fiber product, which is a single-component solid fiber and can impart high antistatic properties and whitening resistance.

  As a result of intensive studies in view of the above prior art, the present inventors have completed the present invention. That is, the present invention is a polyester whose main repeating unit is ethylene terephthalate, and the diol component represented by the following general formula (1) is copolymerized in an amount of 1.0 to 10.0% by mass with respect to the total polyester mass, In addition, a polyester, a polyester fiber, and a polyester product in which sulfoisophthalate is copolymerized in an amount of 0.2 to 1.0 mol% with respect to the dicarboxylic acid constituting the polyester, and the above-described problems can be solved.

［上記式中、Ｒは炭素数１〜１８個の炭化水素基を表し、ｎは４０〜１５０の自然数を表す。］

[In the above formula, R represents a hydrocarbon group having 1 to 18 carbon atoms, and n represents a natural number of 40 to 150. ]

  According to the present invention, it is possible to impart antistatic and whitening resistance with a single-component solid fiber without taking the form of a conventional hollow fiber and core-sheath type composite fiber, and an ultrafine yarn. It is possible to manufacture antistatic fibers with irregular-shaped yarns and textile products using them.

The present invention will be described in detail below.
As the polyester in the present invention, a polyester having an ethylene terephthalate unit obtained by a polycondensation reaction of terephthalic acid and ethylene glycol as a main repeating unit is preferably used. Here, “main” means that 70 mol% or more of all repeating units are ethylene terephthalate units. Preferably it is 80 mol% or more, More preferably, it is 90 mol% or more.

  As a method for producing the polyester used in the present invention, a generally known production method is used. That is, first, a method of directly esterifying a dicarboxylic acid component such as terephthalic acid and a glycol component such as ethylene glycol (esterification reaction step), or a lower alkyl ester of a dicarboxylic acid component such as dimethyl terephthalate and ethylene glycol. A glycol ester of a dicarboxylic acid and / or a low polymer thereof is produced by a method of transesterification with a glycol component in the presence of a transesterification catalyst (transesterification reaction step). Next, this reaction product is heated under reduced pressure in the presence of a polymerization catalyst and subjected to a polycondensation reaction until a predetermined degree of polymerization is obtained (polycondensation reaction step), whereby the desired polyester is produced. Preferred examples of the transesterification reaction catalyst include calcium compounds, magnesium compounds, manganese compounds, zinc compounds, and titanium compounds. Preferred examples of the polymerization catalyst include antimony compounds, germanium compounds, titanium compounds, and aluminum compounds.

  In the polyester used in the present invention, 1.0 to 10.0% by mass of the diol component represented by the following general formula (1) is copolymerized with respect to the total polyester mass, and the sulfoisophthalic acid salt is based on terephthalic acid. It should be 0.2 to 1.0 mol% copolymerized.

［上記式中、Ｒは炭素数１〜１８個の炭化水素基を表し、ｎは４０〜１５０の自然数を表す。］

[In the above formula, R represents a hydrocarbon group having 1 to 18 carbon atoms, and n represents a natural number of 40 to 150. ]

  When the copolymerization amount of the compound represented by the general formula (1) is less than 1.0% by mass, the antistatic property of the obtained polyester fiber becomes insufficient, and when it exceeds 10.0% by mass, the polyester originally has It is not preferable because the characteristics such as heat resistance and dimensional stability are impaired. The copolymerization amount of the compound represented by the general formula (1) is preferably in the range of 1.5 to 7.5% by mass, and more preferably in the range of 2.0 to 5.0% by mass.

  The functional group R of the diol component compound represented by the general formula (1) represents a hydrocarbon group having 1 to 18 carbon atoms. More specifically, methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, t-butyl group, pentyl group, hexyl group, heptyl group, octyl group, 2-ethylhexyl group, Examples thereof include an n-nonyl group, a branched nonyl group, a dodecyl group such as a decyl group and a lauryl group, a tetradecyl group such as a myristyl group, a hexadecyl group such as a palmityl group, and an octadecyl group such as a stearyl group. When the functional group R exceeds 18 carbon atoms, the copolymerized polyester is likely to be thermally decomposed, or there may be a problem that it is impossible to achieve both antistatic properties and whitening resistance. Further, n representing the degree of polymerization of ethylene oxide units is preferably 40 to 150. If it is less than 40, the antistatic property of the polyester may not be exhibited. If it exceeds 150, it is difficult to obtain a polyester having a high intrinsic viscosity (degree of polymerization) that can withstand practical use, or the heat resistance of the polyester is extremely high. It may decrease, which is not preferable. More preferably, the functional group R is a methyl group or an octadecyl group, and n is in the range of 40-100, more preferably n is 40-80. Here, the addition time of the compound of the above formula (1) in the production of the polyester is not particularly limited, but in order to increase the copolymerization rate, any stage after the reaction from the start of the direct esterification reaction, or the transesterification reaction. After completion, the stage before the start of the transesterification reaction is preferred.

  The polyester of this invention needs to copolymerize 0.2-1.0 mol% of sulfo isophthalate with respect to the dicarboxylic acid which comprises a polyester. Examples of sulfoisophthalic acid salts include sulfoisophthalic acid metal salts, sulfoisophthalic acid (quaternary) ammonium salts, and sulfoisophthalic acid phosphonium salts. Among them, the metal types forming the metal salt of sulfoisophthalic acid include Li, Na, K, Ca, Mg, Al, etc., but in view of antistatic properties and cost, alkali metal species are preferable. A salt is more preferred. That is, the sulfoisophthalic acid salt is preferably a sulfoisophthalic acid alkali metal salt, specifically, sulfoisophthalic acid sodium salt, sulfoisophthalic acid lithium salt, or sulfoisophthalic acid potassium salt. These may be used alone or in combination of two or more.

  When the content of these sulfoisophthalates is less than 0.2 mol%, the antistatic property of the resulting polyester fiber is insufficient, and when it exceeds 1 mol%, the thermal stability of the polyester becomes insufficient. This is not preferable because it reduces the yarn strength. The content of sulfoisophthalate is preferably in the range of 0.5 to 0.75 mol%.

  The intrinsic viscosity (solvent: orthochlorophenol, measurement temperature: 35 ° C.) of the polyester of the present invention is not particularly limited, but is preferably in the range of 0.5 to 1.0 dL / g. When the intrinsic viscosity is less than 0.5 dL / g, the mechanical properties of the resulting polyester fiber are insufficient, and when it exceeds 1.0 dL / g, the melt moldability is lowered, which is not preferable. A range of 0.6 to 0.8 dL / g is more preferable.

  The polyester composition of the present invention contains a small amount of additives as necessary, for example, lubricants, radical scavengers, antioxidants, solid phase polymerization accelerators, color adjusters, fluorescent whitening agents, antibacterial agents, ultraviolet absorbers, It may contain a light stabilizer, a heat stabilizer, a light shielding agent, a matting agent, or the like. Of these, the antioxidant is particularly preferably added in order to increase the heat resistance of the polyoxyethylene structure to be added. As the antioxidant to be added, a hindered phenol-based antioxidant is particularly preferable, and the addition amount is preferably in the range of 0.1 to 1.0% by mass with respect to the total polyester mass.

  There is no limitation in particular as a manufacturing method of the polyester fiber of this invention, A conventionally well-known melt spinning method is used. For example, it is preferable to produce a dried polyester composition by melt spinning at a temperature in the range of 270 ° C. to 300 ° C., and the spinning speed of the melt spinning can be 400 to 9000 m / min. It is possible to increase the strength of the material.

  Further, the shape of the die used at the time of spinning is not particularly limited, and any of circular shape, irregular shape, solid shape or hollow shape can be adopted. However, in order to exhibit the characteristics of the polyester fiber of the present invention, solid and atypical are particularly preferable. Furthermore, when manufacturing a polyester product using the polyester fiber of this invention, in order to raise the feel, an alkali weight loss process is also implemented preferably.

  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 characteristics were measured by the following methods.

(A) Intrinsic viscosity:
A dilute solution obtained by dissolving a copolymerized polyester chip sample in orthochlorophenol at 100 ° C. for 60 minutes was determined from a value measured at 35 ° C. using an Ubbelohde viscometer.

(A) Number average molecular weight After dissolving the compound to be analyzed in chloroform, Shodex GPC-101 gel permeation chromatography manufactured by Showa Denko KK is used. Showa Denko Co., Ltd. Shodex KF-800RH was used for the column, chloroform was used for the developing solvent, and the molecular weight distribution was measured with an RH detector. The number average molecular weight was calculated in terms of polystyrene.

(C) Diol component and content of sulfoisophthalate in polyester After dissolving the polymer sample in deuterated trifluoroacetic acid / deuterated chloroform = 1/1 mixed solvent, JEOL A-600 manufactured by JEOL Ltd. A nuclear magnetic resonance spectrum ( ¹ H-NMR) was measured using superconducting FT-NMR, and each content was quantified from the spectrum pattern according to a conventional method.

(D) Antistatic property of fabric Antistatic property (friction band voltage): Antistatic property was evaluated using a rotary drum type friction band voltage measuring device (manufactured by Koa Shokai). A piece of fabric cut into 4 × 8 cm sides is dried, conditioned for 24 hours in an atmosphere at a temperature of 20 ° C. and a relative humidity of 65%, and then at a drum rotation speed of 700 rpm under the conditions of a temperature of 20 ° C. and a relative humidity of 65%. The contact pressure was 600 g, and the friction cloth (white cloth attached to cotton specified in JIS L 0803) was rubbed, and the voltage was measured with an oscilloscope for 1 minute. The highest value was read in 1 minute measurement.

(E) Dyeing of fabric 50 parts by weight of an aqueous dye solution (0.04 parts by weight of a blue disperse dye, 0.025 parts by weight of a dispersion aid, 0.015 parts by weight of acetic acid, 49. parts by weight of distilled water) with respect to 1 part by weight of the fabric. 92 parts by mass) was sealed in a pressure resistant dyeing vessel, heated from room temperature to 130 ° C. at 1.78 ° C./min, held at 130 ° C. for 60 minutes, and cooled from 130 ° C. to 60 ° C. at 2.33 ° C./min. As a result, a dyed fabric was obtained.

(F) Alkali Weight Loss of Fabric With respect to 1000 parts by mass of distilled water, an alkali weight loss solution in which 35 parts by mass of sodium hydroxide is added is heated and refluxed and maintained at 100 ° C., and 2 parts by mass of fabric is added thereto to reduce the amount of alkali. Carried out. The fabric after reducing the alkali is dried in a steam dryer at 120 ° C. for 60 minutes, then left in a desiccator containing a desiccant (silica gel) in an atmosphere at a temperature of 20 ° C., and then the weight of the sample is measured. The weight loss rate was calculated. The alkali weight loss rate is defined by the following formula.
(Alkali weight loss rate) = (W ₀ −W ₁ ) / (W ₀ )
(W ₀ ) = (Mass of fiber product before alkali treatment)
(W ₁ ) = (Mass of fiber product after alkali treatment)

(G) Whitening resistance of the fabric The whitening resistance was evaluated by using a Hunter-type color difference meter (CR-200 type) manufactured by Minolta Co., Ltd. for the dyed fabric. L represents the lightness, and the larger the value, the higher the lightness, so that it can be used as a whiteness index. Therefore, ΔL (L value of fabric dyed after alkali weight reduction—L value of fabric dyed without alkali weight loss) was measured, and when ΔL was 4 or more, whitening resistance ×, ΔL was less than 4 In the case, it was determined as whitening resistance ○.

[Example 1]
-Manufacture of a polyester chip In a mixture of 95 parts by mass of dimethyl terephthalate, 7.63 parts by mass of dimethyl sodium 5-sulfoisophthalate and 70 parts by mass of ethylene glycol, 0.063 parts by mass of calcium acetate monohydrate, 0. 056 parts by mass were charged into a reactor equipped with a stirrer, a rectifying column and a methanol distillation condenser, and methanol produced as a result of the reaction was distilled out of the reactor while gradually raising the temperature from 140 ° C to 240 ° C. The ester exchange reaction was carried out. Thereafter, 0.058 parts by mass of trimethyl phosphate was added to complete the transesterification reaction. Thereafter, 2.0 parts by mass of diol (2) (number average molecular weight 3000, n = about 65) represented by the following chemical formula (2) and 0.04 parts by mass of diantimony trioxide are added to the reaction product, It moved to the reaction container provided with the stirring apparatus, the nitrogen inlet, the pressure reduction port, and the distillation apparatus, heated up to 285 degreeC, and performed the polycondensation reaction by the high vacuum of 30 Pa or less. 30 minutes before the completion of the polymerization reaction, the inside of the system was once returned to normal pressure with nitrogen, 0.4 parts by mass of Irganox 1010 (Ciba Specialty Chemicals) was added as an antioxidant, and again at a high vacuum of 30 Pa or less. A polycondensation reaction was performed to obtain a polyester having an intrinsic viscosity of 0.63 dL / g. Furthermore, it was made into a chip according to a conventional method.

・ Manufacture of polyester fiber After drying the obtained chip at 160 ° C. for 4 hours, using a solid fiber die with a round cross section, a yarn of 24 fil is produced at a spinning temperature of 285 ° C. and a winding speed of 400 m / min. Using a single-stage drawing machine, drawing was performed at a drawing load factor of 0.75 times to obtain a drawn yarn of 75 dtex / 24 fil. The drawn yarn thus obtained was further formed into a tubular knitting by a conventional method.

-Preparation of dyed sample A sample dyed the cylinder was prepared.

-Preparation of alkali weight loss sample After the cylinder volume was alkali weight reduced at an alkali weight loss ratio of 15%, a dyed sample was prepared.

-Evaluation About the dyeing | staining sample and the alkali weight loss sample, it measured about the friction charging voltage and the whitening resistance. The results are shown in Table 1.

[Example 2]
In Example 1, it implemented similarly to Example 1 except having changed the quantity of diol (2) and dimethyl sodium 5-sulfoisophthalate. The results are shown in Table 1.

[Example 3]
In Example 1, it implemented like Example 1 except having changed the number average molecular weight of diol (2) into the thing of 2000 (n = about 43). The results are shown in Table 1.

[Example 4]
In Example 1, it implemented like Example 1 except having changed the diol (2) into the diol (3) (Number average molecular weight 3000, n = about 60) represented by following Chemical formula (3). The results are shown in Table 1.

Chemical formula (3)

[Comparative Example 1]
In Example 1, it carried out like Example 1 except having used polyethyleneglycol (average molecular weight 2000) instead of diol (2). The results are shown in Table 1.

[Comparative Example 2]
In Example 1, it implemented like Example 1 except having used polyethyleneglycol (average molecular weight 20000) instead of diol (2). The results are shown in Table 1.

[Comparative Example 3]
A mixture of 100 parts by mass of dimethyl terephthalate and 70 parts by mass of ethylene glycol was charged with 0.063 parts by mass of calcium acetate monohydrate in a reactor equipped with a stirrer, a rectifying column and a methanol distillation condenser. The ester exchange reaction was carried out while gradually raising the temperature to 240 ° C. and distilling methanol produced as a result of the reaction out of the reactor. Thereafter, 0.058 parts by mass of trimethyl phosphate was added to complete the transesterification reaction. Thereafter, 0.04 parts by mass of antimony trioxide and 1.5 parts by mass of 20% ethylene glycol slurry of titanium dioxide were added to the reaction product, and the reaction was equipped with a stirrer, nitrogen inlet, vacuum port and distillation unit. It moved to the container, heated up to 285 degreeC, and polycondensation reaction was performed by the high vacuum of 30 Pa or less. Thirty minutes before the completion of the polymerization reaction, the system was once returned to atmospheric pressure with nitrogen, 2 parts by mass of polyethylene glycol having a number average molecular weight of 20000, 1 part by mass of sodium tetradecylbenzenesulfonate, and Irganox 1010 (as an antioxidant) After adding 0.4 parts by mass of Ciba Specialty Chemicals), a polycondensation reaction was again performed under a high vacuum of 30 Pa or less to obtain a polyester having an intrinsic viscosity of 0.65 dL / g. The same procedure as in Example 1 was performed except for the method for producing the polyester chip. The results are shown in Table 1.

  According to the present invention, it is possible to achieve both antistatic properties and whitening resistance in polyethylene terephthalate fibers.

Claims (3)

The main repeating unit is a polyester having ethylene terephthalate, and the diol component represented by the following general formula (1) is copolymerized in an amount of 1.0 to 10.0% by mass with respect to the total polyester mass, and sulfoisophthalate. Is a polyester copolymerized in an amount of 0.2 to 1.0 mol% with respect to the dicarboxylic acid constituting the polyester.

[In the above formula, R represents a hydrocarbon group having 1 to 18 carbon atoms, and n represents a natural number of 40 to 150. ]   A polyester fiber obtained by melt spinning the polyester according to claim 1.   A polyester fiber product comprising the polyester fiber according to claim 2.