JPH0374430A - Production of polyester - Google Patents

Abstract

PURPOSE:To obtain a polyester, excellent in antimicrobial, deodorizing and freshness retaining properties and moldability and suitable as fiber for wadding of FUTON (thick bedquilt), socks, stockings, etc., packaging films, etc., by copolymerizing specific components and adding a glycol-soluble silver compound thereto. CONSTITUTION:The objective polymer obtained by adding and copolymerizing (C) (i) an aromatic dicarboxylic acid (derivative) containing metal sulfonate group nuclearly substituted therein in an amount of 1-10wt.% based on the whole acid component or (ii) a polyalkylene glycol (derivative) having 300-6000 number-average molecular weight in an amount of 1-20wt.% based on the whole acid component with (A) a terephthalic acid component and (B) a 2-10C diol component and adding (D) a glycol-soluble silver compound (e.g. silver acetate or silver lactate) in an amount of 1X10<-4> to 1wt.% (based on the polyester) thereto in a stage before completing polycondensation.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a method for producing polyester having excellent antibacterial properties.

[Prior Art] Polyester, particularly polyethylene terephthalate, has excellent properties such as heat resistance and chemical resistance, and is therefore widely used in applications such as clothing, industrial materials, and bedding.

In recent years, there has been an increasing demand for fibers with antibacterial properties as one of the comfort functions in these fiber applications.

Generally, methods for imparting antibacterial properties to fibers include aromatic halogen compounds, organic silicone quaternary ammonium salts,
A method has been adopted in which organic nitrogen compounds or the like are attached to fibers, but these compounds tend to fall off when washed or the like, so there is a problem with durability.

Therefore, as an antibacterial agent, a method of precipitating metallic silver by irradiating a substrate with a silver compound attached with light (Japanese Patent Application Laid-Open No. 1989-50
6717), a method for fixing metals such as gold, silver, copper, and their oxide particles to the surface of fibers (Japanese Unexamined Patent Publication No. 1973-
82500@publication> has been proposed. however,
These particles are not only expensive, but the particles themselves are colored, resulting in undesirable coloration to the product, and their high specific gravity makes it difficult to mold as the particles settle when blended into resin. However, there was a problem in that particles easily fell off because they had no affinity with fibers.

For this reason, a method of blending zeolite particles carrying antibacterial metal ions with a polymer material (Japanese Patent Publication No. 63-54013
@Publication> is proposed.

However, if you try to blend these particles into polyester, the particles are highly hygroscopic, which may cause foaming or hydrolysis of the polyester, and even after blending into polyester, the particles tend to absorb moisture, resulting in cracks and cracks. There was a problem that polyester became colored over time. Therefore, zeolite particles are mixed with liquid paraffin,
A method of improving moldability by coating with a silicone coating agent or fluororesin to make it hydrophobic (JP-A-62-7746, JP-A-62-7746)
7747, JP-A-62-77488) A method of blending zeolite particles carrying antibacterial metal ions and ammonium ions with a discoloration inhibitor (JP-A-63-26)
No. 958) has been proposed.

However, even with these proposals, the improvement effect is insufficient.

[Problems to be Solved by the Invention] The present inventors have conducted studies aimed at providing a polyester that does not have the drawbacks of the conventional methods described above, has durable antibacterial action, and has excellent antibacterial action. , a hydrophilic polyester on which metallic silver particles have been precipitated has antibacterial properties by sufficiently contacting water with the metallic silver particles inside the polyester to generate silver ions, and the silver ions being moderately and slowly released to the outside of the polyester. The present invention was completed by discovering that the antibacterial effect is stable over a long period of time, and that the above-mentioned conventional drawbacks are not present.

[i! ! [Means for Solving the Problem] The object of the present invention described above is to obtain a terephthalic acid component and a carbon atom having 2 carbon atoms.
When producing a polyester having the diol component of ~10 as a main component, at any stage until the polycondensation reaction of the polyester is completed, (1) an aromatic dicarbonate having a sulfonic acid metal group as a nuclear substituent 11! and/or its ester-forming derivatives from 1 to 10 mol % based on the total acidic components, or polyalkylene glycols with a number average molecular weight of 300 to 6,000 and/or their ester-forming derivatives from 1 to 20 mol % based on the polyester! This can be achieved by a method for producing polyester, which involves adding a glycol-soluble silver compound in an amount of 1X'IO4 to 1% by weight relative to the polyester in terms of metallic silver.

The polyester of the present invention can be produced by an esterification method using terephthalic acid and a diol as the main starting materials, a transesterification method using a lower alkyl ester of terephthalic acid and a diol as the main starting materials, or a transesterification method using terephthalic acid and an alkylene oxide as the main starting materials. It can be produced by polycondensing monomers and low polymers thereof obtained by a method such as an addition method.

The polyester of the present invention has a terephthalic acid component and a carbon number of 2.
~10 diol components are the main constituents, and specifically, ethylene glycol, 1,2
-propylene glycol, tetramethylene glycol,
Examples include aliphatic diol components such as 1,5-bentanediol, 1,6-hexanediol, cyclohexanedimethanol, and hydroquinone, alicyclic diol components, and aromatic diol components, which may be used singly or in combination. You can. An aliphatic diol component having 2 carbon atoms, ie, ethylene glycol, is preferred from the standpoint of obtaining a polyester with excellent heat resistance and mechanical properties. In addition, specific components other than these main components include dicarboxylic acid components such as isophthalic acid, naphthalene dicarboxylic acid, adipic acid, and sebacic acid, spiroglycol, and ethylene oxide of bis(4-hydroxyphenyl) sulfone. Examples include adducts, diol components such as ethylene oxide adducts of 2,2-bis(4-hydroxyphenyl)propane, and oxycarboxylic components such as hydroxybenzoic acid and caproladone.

In the present invention, the aromatic dicarboxylic acid having a sulfonic acid metal group as a nuclear substituent and/or its ester-forming derivative must be added in an amount of 1 to 10 mol%, and 2 to 8 mol%, based on the acetic acid component. is preferable, and 3 to 7 mol% is more preferable. In addition, the number average molecular weight is 300 to 60
00 polyalkylene glycol and/or its ester-forming derivative is 1 to 20% relative to the polyester.
% by weight, preferably 2-15% by weight, more preferably 3-10% by weight. The amount of the aromatic dicarboxylic acid and/or ester-forming derivative having a sulfonic acid metal group as the nuclear substituent is 2 mol% (
(relative to total acid components), or the number average molecular weight is 300 to 6.
000 polyalkylene glycol and/or its ester-forming derivative (based on polyester) is 1
If the amount is less than % by weight, the resulting polyester will lack hydrophilicity, and silver ions will not be released in a sustained manner from the metal silver particles present inside the polyester, and the polyester will not exhibit the antibacterial properties that are the object of the present invention.

In addition, the amount of aromatic dicarboxylic acid and/or its ester-forming derivative having a sulfonic acid metal group as a nuclear substituent is more than 10 mol %, or polyalkylene glycol and/or having a number average molecular weight of 300 to 6000 is added. The amount of the ester-forming derivative added is 20
If the amount is more than %, the mechanical properties of the resulting polyester will deteriorate.

Furthermore, if the number average molecular weight of the polyalkylene glycol and/or its ester-forming derivative is less than 300, the hydrophilicity of the obtained polyester will be insufficient, so that the antibacterial properties aimed at by the present invention will not be expressed. 6
If it exceeds 000, it will not be copolymerized into the polyester molecular chain,
The resulting polyester no longer has uniform hydrophilicity and has a low antibacterial effect.

Specifically, the aromatic dicarboxylic acids and/or ester-forming derivatives thereof having a sulfonic acid metal group as an IFIAll substituent used in the present invention include 5-metal sulfoisophthalic acid, 2-metal sulfoterephthalic acid, and their lower Examples include alkyl esters,
Specific examples of the metal include alkali metals such as lithium, sodium, and potassium.

In addition, as polyalkylene glycols and/or ester-forming derivatives thereof having a number average molecular weight of 300 to 6,000, specifically, polyethylene glycol, poly(
1,2-propylene glycol), polytetramethylene glycol, and the like.

In the present invention, aromatic dicarboxylic acids and/or ester-forming derivatives thereof having a sulfonic acid metal group as a nuclear substituent, or having a number average molecular weight of 300 to 600
The polyethylene glycol and/or its ester-forming derivative can be added at any stage until the polycondensation reaction of the polyester is completed, but it is possible to add the polyethylene glycol and/or its ester forming derivative at any stage until the polycondensation reaction of the polyester is completed. It is preferable to add it before the auxiliary stage of the polycondensation reaction. In addition, an aromatic dicarboxylic acid having a sulfonic acid metal group as a nuclear substituent and/or an ester-forming derivative thereof and an average molecular weight of 300 to 6000.
The polyalkylene glycol and/or its ester-forming derivative can be added in combination.

Specifically, the glycol-soluble silver compounds used in the present invention include silver acetate, silver propionate, silver acetate,
Preferred examples include silver aliphatic carboxylates such as silver lactate, silver aromatic carboxylates such as silver benzoate and silver phenylacetate, silver alicyclic carboxylates such as silver cyclohexanecarboxylate, silver halogen acids, silver nitrate, and silver sulfate. Silver aliphatic carboxylates, silver aromatic carboxylates, and silver alicyclic carboxylates are more preferred, and aliphatic carboxylic acids are even more preferred, since more uniform and fine metallic silver particles can be precipitated in the polyester. . These silver compounds can be used alone or in combination.

In addition, these glycol-soluble silver compounds can be added at any stage until the polycondensation reaction of polyester is completed, but since they can precipitate more uniform and fine metallic silver particles into the polyester, It is preferable to add it by the first light stage of . Glycol-soluble silver compounds are partially or completely dissolved in the low polymer when the polyester is a low polymer in the polyester manufacturing process, but as the degree of polymerization of the polyester increases, the solubility decreases and the polyester manufacturing process By being reduced by a reducing substance such as an aldehyde that is produced as a by-product in the process, it can be precipitated into polyester as fine metal silver particles. Furthermore, since it is possible to precipitate more uniform and fine metallic silver particles, it is preferable to dissolve or disperse a glycol-soluble silver compound in a solvent such as glycol before adding it. For the purpose of increasing solubility, etc., it is also preferable to add an ammonium compound or the like to the solvent. Furthermore, it is more preferable to use the same glycol as the diol component, which is the main component of the polyester, as the solvent.

Roughly speaking, the glycol-soluble silver compound needs to be added in an amount of 1X10''4 to 1% by weight relative to the polyester in terms of metallic silver, preferably 3X10' to 3×10-1% by weight, and 1X10'' to 1X10% by weight. '% by weight is more preferable. If the amount added is less than 1 x 104% by weight, the antibacterial effect of the polyester obtained will be insufficient, and if it exceeds 1% by weight, not only will the antibacterial effect become saturated, but the cost of polyester production will increase. Moreover, the color tone of the obtained polyester deteriorates.

Compared to polyester obtained by simply adding metal silver particles to the polyester manufacturing process, the polyester obtained by the method of the present invention not only has fine metal silver particles stably present in the polymer but also has uniformity. Since it contains fine metallic silver particles, it exhibits excellent antibacterial properties even with a small amount of silver compound added in terms of metallic silver, and also has excellent formability into fibers and films.

The polyester of the present invention includes matting agents, deodorants, colorants,
Additives such as ultraviolet absorbers, infrared absorbers, flame retardants, optical brighteners, antioxidants, ion adsorbents, and other antibacterial agents can be contained depending on the purpose.

[Example] The present invention will be described in detail by giving examples below. Each characteristic value in the examples was determined according to the following method.

(A) Intrinsic viscosity: Dissolved in orthochlorophenol and determined at 30°C.

(B) Antibacterial evaluation of tube knitted fabric (i!ti: test bacteria (E. coli ESC CheriChia C01f NIH)
J or Staphylococcus aureus 5taphy l 0COc
cs aereus IFO12732) in a column, measure the number of viable bacteria after 1 hour of incubation at 150 times/min in a sealed container, and calculate the rate of decrease relative to the number of bacteria in the added suspension. shake flask method).

Example 1 93.6 parts by weight of dimethyl terephthalate, 7.5 parts by weight of dimethyl 5-sodium sulfoiphthalate (5 mol% based on the total acid components), 60 parts by weight of ethylene glycol, and 0 manganese acetate as a transesterification catalyst. .03 parts by weight was placed in a transesterification reactor and heated from 130°C to 230°C.
The methanol by-produced was distilled off by heating until the transesterification reaction was carried out. Then, 0.02 parts by weight of trimethyl phosphate and 0.04 parts by weight of antimony trioxide were added, and 0.04 parts by weight of silver acetate was added. .0155 parts by weight (2% by weight based on polyester) was added as an ethylene glycol dispersion and heated at 235°C for 30 minutes under normal pressure.
Excess ethylene glycol was distilled off by heating to complete the transesterification reaction. Subsequently, the reactant was transferred to a polycondensation reactor and gradually heated and depressurized to conduct a vacuum condensation reaction at 290° C. to obtain a polyester having an intrinsic viscosity of 0.63.

A small amount of this polymer was sandwiched between two cover glasses at 280°C.
When the polymer was melted and rapidly cooled and observed under a microscope, fine particles with a particle size of about 0.1 μm were precipitated in the polymer. In addition, a diffraction peak based on metallic silver was detected by X-ray diffraction of particles obtained by dissolving this polymer in orthochlorophenol and centrifuging the particles. This polymer was further spun using a conventional melt spinning method and then drawn to obtain a drawn yarn of 75 denier and 24 filaments without any yarn breakage.

This drawn yarn is tube-knitted and refined, and further 10
Antibacterial properties were evaluated after washing 0 times.

The bacterial count reduction rate was 99.9 for E. coli in the sample after scouring.
%, 98.5% against Staphylococcus aureus, 99.9% against Escherichia S. aureus in the sample after washing, and 98.3% against Staphylococcus aureus, which was excellent for all samples. It was found to have antibacterial effects.

Comparative Example 1 In place of silver acetate in Example 1, 0,101 parts by weight of metallic silver particles (average particle diameter -1.3 μm) were added to obtain a polyester having an intrinsic viscosity of 0.62. After this polymer was taken out, a large amount of metal silver particles that were supposed to have been added remained at the bottom of the polycondensation reactor.

When this pellet was spun and drawn, yarn breakage occurred, but a drawn yarn of 75 denier and 24 filaments could be obtained.

This drawn material is cylindrically knitted and refined, and further 100%
The antibacterial properties of the items that had been washed twice were evaluated.

The bacterial count reduction rate was 67.4 for E. coli in the sample after scouring.
%, 56.8% against Staphylococcus aureus, 65.9% against E. coli in the sample after washing, and 56.5% against Staphylococcus aureus. In comparison, the antibacterial performance was inferior.

Example 2 Transesterification of 94 parts by weight of dimethyl terephthalate, 60 parts by weight of ethylene glycol, parts by weight of polyethylene glycol having a number average molecular weight of 1000 (7% by weight based on polyester), and 0.03 parts by weight of manganese acetate as a transesterification reaction catalyst. Place in a reaction vessel and heat from 130℃ to 230℃
By gradually heating the mixture until the temperature reached 100°C, the methanol produced as a by-product was distilled off, and the transesterification reaction was carried out.

Next, 0.02 parts by weight of trimethyl phosphate and 0.04 parts by weight of antimony trioxide were added, and 0.0 parts by weight of silver acetate was added.
155 parts by weight (1×10″2% by weight based on polyester)
> was added as an ethylene glycol dispersion, and
Excess ethylene glycol was distilled off by heating to 235° C. for 0 minutes to complete the transesterification reaction. Subsequently, the reactants were transferred to a polycondensation reactor and gradually heated and depressurized to produce 2
Condensation reaction was carried out at 90℃ under vacuum, and the intrinsic viscosity was 0.6.
Polyester No. 1 was obtained.

It was confirmed that fine metallic silver particles having a particle diameter of about 0.1 μm were precipitated in this polymer. This polymer was further spun using a normal melt spinning method and then stretched to produce a 75 denier 24
A drawn filament yarn was obtained.

This drawn yarn is tube-knitted and refined, and further 10
Antibacterial properties were evaluated for items that had been washed 0 times.

The bacterial count reduction rate was 99.9 for E. coli in the sample after scouring.
%, 98.5% against Staphylococcus aureus, 99.9% against E. coli after washing, and 98.0% against Staphylococcus aureus, showing excellent antibacterial effects for all samples. It was found that it has.

Comparative Example 2 A polyester having an intrinsic viscosity of 0.63 was obtained in the same manner as in Example 2, except that polyethylene glycol having a number average molecular weight of 1000 was not added. It was confirmed that fine metal particles with a particle diameter of about 0.1 μm were precipitated in this polymer. This polymer is further spun using a normal melt spinning method and then stretched.
A drawn yarn of 75 denier and 24 filaments was obtained without yarn breakage.

This drawn yarn is tube-knitted and refined, and further 10
When the antibacterial properties of the clothes that had been washed 0 times were evaluated, the number of bacteria did not decrease.

Example 3 89 parts by weight of dimethyl terephthalate, 7.1 parts by weight of dimethyl 5-sodium sulfoisophthalate (5 mol% based on the total acid components), 60 parts by weight of ethylene glycol, parts by weight of polyethylene glycol having a number average molecular weight of 4000 ( 5% by weight of the polyester> and 0.03 parts by weight of manganese acetate as a transesterification reaction catalyst were placed in a transesterification reactor and gradually heated from 130°C to 230°C to distill off the methanol produced as a by-product and carry out transesterification. The reaction was carried out. Next, 0.02 parts by weight of trimethyl phosphate and 0.04 parts by weight of antimony trioxide were added, and 0.0078 parts by weight of silver acetate (5 parts by weight based on polyester) was added.
10' parts by weight) was added as an ethylene glycol dispersion, and the mixture was heated at 235° C. for 30 minutes under normal pressure to distill off the ethylene glycol to complete the transesterification reaction. Subsequently, the reactant was transferred to a polycondensation reactor and gradually heated and depressurized to perform a vacuum condensation reaction at 290° C. to obtain a polyester having an intrinsic viscosity of 0.65. It was confirmed that fine metallic silver particles having a particle diameter of about 0.1 μm were precipitated in this polymer. This polymer is further spun using a normal melt spinning method and then stretched.
A drawn yarn of 75 denier and 24 filaments was obtained without yarn breakage.

This drawn yarn is tube-knitted and refined, and further 10
Antibacterial properties were evaluated for items that had been washed 0 times.

The bacterial count reduction rate was 99.9 for E. coli in the sample after scouring.
%, 98.9% against Staphylococcus aureus, 99.9% against E. coli after washing, and 98.5% against Staphylococcus aureus, showing excellent antibacterial effects for all samples. It was found that it has.

Examples 4 to 8 and Comparative Examples 3 to 4 Types of aromatic dicarboxylic acid compounds having sulfonic acid metal bases as nuclear substituents (A compounds), polyethylene glycol compounds (B compounds), and glycol-soluble silver compounds (C compounds) After polyester was obtained in the same manner as in Example 1 by changing the amount of polyester added, the antibacterial properties of tube-knitted fabrics made from these drawn yarns were investigated, and the results are shown in Table 1. As is clear from the description in Table 1, the antibacterial properties aimed at by the present invention could not be obtained in Comparative Examples 3 and 4, which did not satisfy the requirements of the present invention.

Example 9 81.9 parts by weight of dimethyl terephthalate, 6.6 parts by weight of dimethyl 5-sodium sulfoisophthalate (5 mol% based on the total acid components), 80 parts by weight of tetramethylene glycol, and 10 parts by weight of titanium tetraiso as a reaction catalyst. 0.
05 parts by weight was placed in a transesterification reactor and gradually heated from 130°C to 210°C to distill off by-produced methanol along with a small amount of tetrahydrofuran to carry out transesterification. Then silver acetate 0.0155
Part by weight (1X10-2 in terms of metallic silver based on polyester)
%) was added as a tetramethylene glycol dispersion and heated to 220° C. for 30 minutes under normal pressure to distill off excess tetramethylene glycol to complete the transesterification reaction. Subsequently, the reactant was transferred to a polycondensation reactor and gradually heated and depressurized to conduct a condensation reaction at 250° C. under vacuum to obtain a bo1-noester having an intrinsic viscosity of 0.76°. It was confirmed that fine gold film particles having a particle size of about 0.1 μm were precipitated in this polymer. This polymer was roughly spun using a conventional melt spinning method and then drawn to obtain a drawn yarn of 75 denier and 24 filaments without yarn breakage.

This drawn yarn is tube-knitted and refined, and further 10
VN bacterial susceptibility was evaluated for items that had been washed 0 times.

Bacterial count reduction rate, 99.9 against Escherichia coli in samples after Separation II
%, 98.2% against Staphylococcus aureus, 99.9% against E. coli after washing, and 97.6% against Staphylococcus aureus, showing excellent antibacterial effects for all samples. It was found that it has.

[Effect of the invention] Since the present invention has the above-described configuration, the obtained polyester has excellent antibacterial and ε moldability, as well as odor resistance and freshness retention properties, so it can be used as a futon. It can be used for fiber applications such as cotton and socks, film applications such as packaging films, and other molded product applications. When used in textile applications, it can be used as composite fibers such as core-sheath type composites used in the core or sheath, and can be used in rough, blended, blended, intertwined or interlaced knitting. You can also do that.

Claims (1)

[Scope of Claims] When producing a polyester whose main components are a terephthalic acid component and a diol component having 2 to 10 carbon atoms, at any stage until the polycondensation reaction of the polyester is completed, (1) An aromatic dicarboxylic acid having a sulfonic acid metal group as a substituent and/or its ester-forming derivative in an amount of 1 to 10% based on the total acid component, or a polyalkylene glycol having a number average molecular weight of 300 to 6,000 and/or its ester. 1 to 20% by weight of a forming derivative is added to the polyester and copolymerized, and (2) a glycol-soluble silver compound is added to the polyester in an amount of 1 x 10^-4 to 1% by weight in terms of metallic silver. A method for producing polyester, characterized by: