JP2001192934A - Method of producing polyester fiber excellent in water absorption property - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method of producing a polyester fiber having excellent water absorption properties comparable to those of natural fibers. SOLUTION: The water absorption properties of a polyester fiber are improved by adding inorganic particles excellent in hydrophilic properties such as calcium oxide and subsequently spinning the mixture in producing the polyester fiber.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a polyester fiber such as cotton or wool having excellent water absorbency comparable to existing natural fibers.

[0002]

2. Description of the Related Art In general, a polyester fiber is an aromatic dicarboxylic acid such as terephthalic acid or 2,6-naphthalenedicarboxylic acid or an ester-forming derivative thereof, and a polycondensation synthetic fiber using ethylene glycol as a main starting material. is there.

[0003] Polyester fibers have excellent properties such as mechanical properties and heat resistance, but have high crystallinity of the fiber structure and extremely dilute functional groups having an affinity for water in the molecule. Water absorbency is lower than that of natural fibers such as cotton or regenerated cellulose, and water absorption has been a problem when used in an environment where water absorbency is required. As used herein, the term "water-absorbing" refers to the property of absorbing water when the fiber takes the form of fiber aggregates such as yarn, strand, woven, knitted or non-woven fabric.

[0004] Therefore, researches for imparting excellent water absorption while maintaining the existing excellent properties of the polyester fiber have been actively conducted. For example, U.S. Pat. No. 3,329,557 and British Patent No. 956,833 disclose a method of blending a polyester with a hydrophilic polyalkylene glycol and then producing a fiber by a process such as spinning. . However, the polyethylene fiber produced by this method has problems that the mechanical properties are deteriorated and the water absorption does not reach a satisfactory level.

Further, Korean Patent Publication No. 93-6779 discloses a method of adding an organic compound having a specific polyalkylene polyamine as a main chain to polyester, and Korean Patent Publication No. 86-397 discloses a method. ROSO ₃ M (where R represents an alkyl group having 1 to 30 carbon atoms or an alkylaryl group or an allyl group having 7 to 40 carbon atoms), and M represents an alkali metal or an alkaline earth metal. Is added and spun, and after the knitting or weaving, an elution treatment with an alkaline aqueous solution is performed to make the fibers porous. However, although the polyester fiber produced by these methods has improved water absorption, it has a problem that the production cost increases because the added compound is expensive and an additional step such as a dissolution treatment step is required. Was.

[0006]

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and has as its object to improve the water absorption of polyester fiber by using inexpensive inorganic particles. .

[0007]

According to the present invention, there is provided a method for producing a polyester fiber, comprising one or more inorganic oxide particles selected from calcium oxide particles, magnesium oxide particles and manganese oxide particles having a specific amount and a specific size. The present invention provides a method for producing a polyester fiber, which comprises spinning after adding particles.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be specifically described below.

In the present invention, the polyester is produced using aromatic dicarboxylic acid or an ester-forming derivative thereof and ethylene glycol as main starting materials, but may contain other third components. Here, as the aromatic dicarboxylic acid component, isophthalic acid, terephthalic acid, 2,6
-One or a mixture of two or more selected from naphthalenedicarboxylic acid, phthalic acid, adipic acid and sebacic acid can be used. As the glycol component, in addition to ethylene glycol, which is the main component, propylene glycol,
Butanediol, 1,4-cyclohexanedimethanol, neopentyl glycol and the like may be contained.

[0010] If necessary, additives such as a heat stabilizer, an antiblocking agent, an antioxidant, an antistatic agent and an ultraviolet absorber can be added to the polyester used in the present invention.

Further, in the present invention, it is necessary to mix one or more kinds selected from calcium oxide particles, magnesium oxide particles and manganese oxide particles into a spinning raw material before spinning. At this time, the inorganic particles should be added at the polyester polymerization stage, after the polyester is produced and then fed to the spinneret, or when the polyester chips are produced and used as a spinning material, they should be added at the chip elution and extrusion stage. Is desirable. For example, when the inorganic particles are added at the polyester polymerization stage, it is preferable to add the inorganic particles at the completion of the esterification reaction or at the polycondensation stage, and at this time, the inorganic particles contain water that inhibits the reaction. Desirably not.

After the polyester is produced through a polycondensation reaction, the polymer is pumped to a spinneret. At this stage, at least one selected from calcium oxide particles, magnesium oxide particles, and manganese oxide particles is used. May be added, as a method of adding, after separating a part of the polymer from the main pipe and allowing the inorganic particles to be contained,
Means for mixing the polymer with the polymer in the main pipe again can be adopted.

On the other hand, when the polyester already produced is extruded by a melt extruder and cut into chips, and the chips are used for producing fibers, it is necessary to directly add and mix the inorganic particles during melt extrusion of the chips. desirable. In addition, the inorganic particle-containing polyester chip produced in this way alone or after mixing with other general polyester chips,
It can be used as a spinning raw material.

For example, the calcium oxide particles used in the present invention are obtained by finely pulverizing a rough calcium carbonate,
This is burned in a furnace maintained at a temperature of about 1000 ° C.
It can be produced by separating calcium oxide and carbon dioxide. Thus, the raw materials are easily available, the manufacturing process is simple, and the price is low. The calcium oxide particles have high hydrophilicity and react with water at normal temperature to react with calcium hydroxide [ Ca (O
H) ₂ ] and exhibits excellent water absorption.

Magnesium oxide and manganese oxide can also improve water absorption on the same principle as calcium oxide.

As the inorganic particles used at this time, it is desirable to use particles having a particle size of 0.01 to 50 μm. If the particle size is smaller than 0.01 μm, the water absorption tends to decrease,
If it exceeds, during the spinning step or post-processing step,
Thread breakage easily occurs.

The amount of the inorganic particles to be used is preferably about 0.1 to 50% by mass relative to the polyester. If the effect of improving the properties cannot be obtained, and if it exceeds 50% by mass, the mechanical properties of the polyester may be deteriorated.

On the other hand, water and / or
It is also recommended that no impurities be included. When water and / or impurities are contained, not only poor spinnability and post-treatment properties, but also a direct cause of lowering the physical properties of the polyester, if possible,
It is desirable to use one having high purity.

Hereinafter, the present invention will be described more specifically with reference to Examples and Comparative Examples, but the present invention is not limited thereto.

[0020]

[Example 1] 100 parts by mass of terephthalic acid and 45 parts by mass of ethylene glycol were put into a reactor and heated while stirring, and the temperature was raised from 140 ° C to 230 ° C, and the esterification reaction was carried out for 4 hours. Thereafter, a mixture of 0.04 parts by mass of antimony trioxide and 0.015 parts by mass of phosphoric acid mixed with 1 part by mass of ethylene glycol was added.
The temperature was raised to the range of 230 to 285 ° C., and a polycondensation reaction was carried out under reduced pressure for 4 hours to obtain a polyester (1). After solidifying the polyester (1) with liquid nitrogen, 80 parts by mass of a polyester powder obtained by pulverization and calcium oxide (particle size: 0.01 to 50 μm, average particle size: 0.4 μm)
m) After mixing with 20 parts by mass of the mixture for 30 minutes, the twin-screw extruder was operated in a vacuum state at 240 to 290 ° C to obtain a polyester (2). 90 parts by mass of the polyester (1) and 10 parts by mass of the polyester (2) were mixed, dried with hot air at 160 ° C. for 6 hours, melted at 290 ° C. using a melt extruder, and spun through a spinneret. Then, it was drawn to obtain a 75/24 polyester fiber.

Example 2 The same procedure as in Example 1 was carried out except that 95 parts by mass of the polyester (1) obtained in Example 1 and 5 parts by mass of the polyester (2) were mixed.
4 polyester fibers were obtained.

Comparative Example 1 The polyester (1) obtained in Example 1 was solidified with liquid nitrogen and then pulverized to obtain 80 parts by mass of a polyester powder and colloidal silica particles (particle size 0.3 μm). ) After mixing 20 parts by mass for 30 minutes, the twin screw extruder was operated in a vacuum state at 240 to 290 ° C to obtain a polyester (3). After mixing 90 parts by mass of the polyester (1) and 10 parts by mass of the polyester (3) and drying with hot air at 160 ° C. for 6 hours, the mixture is melted by operating a melt extruder at 290 ° C., and the mixture is melted through a spinneret. After spinning, it was drawn to obtain a 75/24 polyester fiber.

Comparative Example 2 The same procedure as in Comparative Example 1 was repeated except that 95 parts by mass of the polyester (1) synthesized in Example 1 and 5 parts by mass of the polyester (3) were mixed.
4 polyester fibers were obtained.

The physical properties of the polyesters obtained in the above Examples and Comparative Examples were measured and are shown in Table 1 below.

[0025]

[Table 1]

[0026]

As can be seen from the above Examples and Comparative Examples, when the polyester fiber is produced by the method of the present invention, the water absorption is greatly improved as compared with the existing method. Also, since the price of the inorganic particles used in the present invention is low,
The polyester fiber excellent in water absorption was able to be provided at low cost.

Claims (3)

[Claims] In a method for producing a polyester fiber, one or more inorganic particles selected from calcium oxide particles, magnesium oxide particles and manganese oxide particles are added in an amount of 0.1 to 50 mass% of the total mass of the spinning raw material. %, Followed by spinning, wherein the polyester fiber has excellent water absorption. 2. The method according to claim 1, wherein the inorganic particles are added at a polyester polymerization stage or after a polyester is produced and then fed to a spinneret or at a chip melt extrusion stage when polyester chips are used as a spinning raw material. The method for producing a polyester fiber excellent in water absorbency according to claim 1. 3. The size of the inorganic particles is 0.01 to 50.
3. The method according to claim 1, wherein the distance is in the range of μm.
3. The method for producing a polyester fiber having excellent water absorbency according to item 1.