JP2002332333A - Polyester and production method for polyester - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a polyester which is produced by using a component other than an antimony compound and a germanium compound as the main component of a catalyst and is excellent in heat stability, color tone, and hydrolysis resistance; and to provide a production method for the polyester. SOLUTION: The polyester is produced by using aluminum and/or its compound and cobalt and/or its compound as a catalyst and contains aluminum and/or its compound and cobalt and/or its compound, each in a specified amount.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polyester and a method for producing the polyester. More specifically, the present invention relates to a polyester produced using a component other than an antimony compound and a germanium compound as a main component of a catalyst and having a heat stability. The present invention relates to a polyester excellent in color tone and hydrolysis resistance and a method for producing the polyester.

[0002]

2. Description of the Related Art Polyester, especially polyethylene terephthalate (hereinafter abbreviated as PET) has excellent mechanical properties and chemical properties, and is applicable to various uses, such as fibers for clothing and industrial materials, and fibers for packaging. It is applied to various films and sheets for tapes and magnetic tapes, and molded products such as bottles and engineering plastics.

[0003] In the industrial production of PET, bis (2-hydroxyethyl) terephthalate is produced by esterification or transesterification of terephthalic acid or dimethyl terephthalate with ethylene glycol. Obtained by polycondensation. As a catalyst used in the polycondensation, antimony trioxide is widely used. Antimony trioxide is a catalyst which is inexpensive and has excellent catalytic activity, but has a problem that darkening and foreign matter are generated in PET due to precipitation of metal antimony during polycondensation. Under such circumstances, polyesters containing no or only a very small amount of antimony have been desired.

[0004] Attempts have been made to use antimony trioxide as a polycondensation catalyst and to suppress the occurrence of darkening and foreign matter in PET. For example, in Japanese Patent No. 2666502, the use of a compound of antimony trioxide, bismuth and selenium as a polycondensation catalyst suppresses the formation of black foreign substances in PET. JP-A-9-291141 states that the use of antimony trioxide containing sodium and iron oxides as a polycondensation catalyst suppresses the deposition of antimony metal. However, these polycondensation catalysts cannot achieve the purpose of a polyester containing no antimony after all.

[0005] Studies have been made on polycondensation catalysts that can replace antimony trioxide. In particular, titanium compounds typified by tetraalkoxy titanates have already been proposed. However, PET produced using such compounds has problems that it is significantly colored and that thermal decomposition easily occurs.

As an attempt to overcome such problems when using tetraalkoxy titanate as a polycondensation catalyst, for example, in Japanese Patent Application Laid-Open No. 55-116722, tetraalkoxy titanate is used simultaneously with a cobalt salt and a calcium salt. A method has been proposed. Also, JP-A-8-7358
No. 1 proposes a method in which a tetraalkoxy titanate is used simultaneously with a cobalt compound as a polycondensation catalyst, and a fluorescent brightener is used. However, in these proposals, although the coloring of PET is reduced when tetraalkoxy titanate is used as a polycondensation catalyst, on the other hand,
Effective suppression of thermal decomposition of PET has not been achieved.

Germanium compounds have been put to practical use as a polycondensation catalyst which can replace antimony trioxide and which overcomes problems such as the case where tetraalkoxy titanate is used. It has a problem that it is very expensive and a problem that it is difficult to control polymerization by changing the catalyst concentration of the reaction system because it is easily distilled out of the reaction system during polymerization.

It is known that aluminum compounds generally have poor catalytic activity. Among the aluminum compounds,
Aluminum chelate compounds are known to have higher catalytic activity as polycondensation catalysts than other aluminum compounds, but have sufficient catalytic activity as compared to the above-mentioned antimony compounds and titanium compounds. I could not say. Furthermore, polyesters conventionally polymerized using an aluminum compound as a catalyst could not sufficiently avoid problems such as poor thermal stability, foreign matters derived from the aluminum compound, and coloring.

In order to solve such a problem, for example, USP
5,512,340 and JP-A-10-324741 show that when an aluminum compound such as aluminum hydroxide chloride, aluminum chloride or aluminum acetylacetonate is used in combination with a cobalt compound, the catalytic activity is excellent and the coloring derived from the aluminum compound is improved. Has been proposed. However, polyesters polymerized using an aluminum compound and a cobalt compound as catalysts described in the publication are inferior in heat stability, color tone and hydrolysis resistance, and the polyesters are dark and have poor appearance of molded articles. Met.

[0010]

SUMMARY OF THE INVENTION The present invention relates to a polyester produced using a component other than an antimony compound and a germanium compound as a main component of a catalyst, and solves the above-mentioned problems concerning heat stability, color tone and hydrolysis resistance. It is intended to provide a solved polyester and a method for producing the polyester.

[0011]

Means for Solving the Problems The present inventors have conducted intensive studies with the aim of solving the above-mentioned problems, and as a result, when producing a polyester using an aluminum compound and a cobalt compound as a catalyst, an aluminum compound and By using the amount of the cobalt compound within a specific range, thermal stability,
It has been found that a polyester excellent in color tone and hydrolysis resistance can be obtained.

The present invention is directed to a method for solving the above-mentioned problems of heat stability, color tone and hydrolysis resistance of a polyester, which is a polyester produced by using an aluminum compound and a cobalt compound as a catalyst, wherein Provided is a polyester in which the amounts of the compound and the cobalt compound satisfy the following formulas (1) and (2). Co ≦ 4 (ppm) (1) 0.5 ≦ Al / Co ≦ 45 (2) (In the formulas (1) and (2), Al and Co are the contents of aluminum atoms and cobalt atoms contained in the polyester, respectively. (Ppm).)

The present invention also provides a method for producing a polyester by using an aluminum compound and a cobalt compound as a catalyst so that the content thereof in the polyester falls within the above range.

The present invention also provides a catalyst system for maintaining a high catalytic activity even when the aluminum compound and the cobalt compound are within the above specific ranges.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION The aluminum compound that can be used in the present invention is not particularly limited.
Aluminum formate, aluminum acetate, basic aluminum acetate, aluminum propionate, aluminum oxalate, aluminum acrylate, aluminum laurate, aluminum stearate, aluminum benzoate, aluminum trichloroacetate, aluminum lactate,
Carboxylates such as aluminum citrate and aluminum salicylate; inorganic acid salts such as aluminum chloride, aluminum hydroxide, aluminum hydroxide chloride, aluminum carbonate, aluminum phosphate and aluminum phosphonate; aluminum methoxide, aluminum ethoxide, and aluminum n -Propoxide, aluminum is
Aluminum chelates such as o-propoxide, aluminum n-butoxide, aluminum t-butoxide, aluminum alkoxide, aluminum acetylacetonate, aluminum acetylacetate, aluminum ethyl acetoacetate, aluminum ethyl acetoacetate di-iso-propoxide, trimethyl aluminum, Organoaluminum compounds such as triethylaluminum and partial hydrolysates thereof,
Aluminum oxide, metal aluminum and the like can be given. Of these, carboxylate, inorganic acid salt and chelate compound are preferable, and among these, basic aluminum acetate, aluminum chloride, aluminum hydroxide, aluminum hydroxide chloride and aluminum acetylacetonate are particularly preferable.

The cobalt compound is not particularly limited. Specifically, for example, cobalt acetate, cobalt nitrate,
Cobalt chloride, cobalt acetylacetonate, cobalt naphthenate, and hydrates thereof are exemplified. Among them, cobalt acetate tetrahydrate is particularly preferred.

In order to solve the problems of heat stability, color tone and hydrolysis resistance of the polyester, the polyester content of the polyester of the present invention is as follows:
It is necessary that the content of cobalt atoms is 4 ppm or less, and the content ratio of aluminum atoms to cobalt atoms is 0.5
It needs to be ~ 45. Preferably, the content of cobalt atoms is 3 ppm or less and the content ratio of aluminum atoms to cobalt atoms is 2.0 to 25, and more preferably the content of cobalt atoms is 2 ppm or less, and the content ratio of aluminum atoms to cobalt atoms is 3.0 to 15. . When the addition amount of the cobalt atom is more than 4 ppm, the obtained polyester has reduced heat stability and hydrolysis resistance. And
If the content ratio of aluminum atoms to cobalt atoms is less than 0.5, the color tone of the polymer becomes dark. On the other hand, if the content ratio of aluminum atoms to cobalt atoms is larger than 45, the color tone of the polymer becomes yellow. Furthermore, the aluminum content in the polyester is
Preferably 120 ppm or less as an aluminum atom,
It is more preferably at most 80 ppm. 120 added
If the amount is more than ppm, the thermal stability of the obtained polyester is reduced, and decomposition or significant coloring may occur during melt molding.

The present invention also relates to a method for producing a polyester by using an aluminum compound and a cobalt compound as a catalyst such that the content of the aluminum compound and the cobalt compound in the polyester is in the above-mentioned range.

When a specific phosphorus compound is contained in the polyester of the present invention, the thermal stability of the polyester is improved, and in addition, the above-mentioned specific amounts of the aluminum compound and the cobalt compound are used. When polymerizing the polyester, it is preferable to use a specific phosphorus compound because the catalytic activity can be improved.

The specific phosphorus compound is at least one selected from phosphorus compounds represented by the following general formulas (Formula 3) and (Formula 4).

[0021]

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(In the formula, R ¹ and R ² each independently represent hydrogen, an alkyl group having 1 to 50 carbon atoms, or an aryl group.)

[0023]

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(In the formula, R ³ and R ⁴ each independently represent hydrogen, an alkyl group having 1 to 50 carbon atoms, or an aryl group.)

The compound represented by the above (Chemical Formula 3) or (Chemical Formula 4) is preferably at least one selected from dimethyl phenylphosphonate and diphenyl methylphosphonate, and the use of dimethyl phenylphosphonate is particularly preferred. preferable.

Although phosphorus compounds are generally well known as antioxidants, even when these phosphorus compounds are used in combination with conventional metal-containing polyester polymerization catalysts,
It is not known to greatly promote melt polymerization. In fact, when melt-polymerizing a polyester using a typical catalyst for polyester polymerization such as an antimony compound, a titanium compound, a tin compound or a germanium compound as a polymerization catalyst, the specific phosphorus compound of the present invention may be added substantially. It is not observed that the polymerization is promoted to a level useful for

The amount of the phosphorus compound of the present invention to be used is preferably 0.0001 to 0.1 mol% with respect to the total number of moles of all constituent units of the polycarboxylic acid component of the obtained polyester.
More preferably, it is 0.005 to 0.05 mol%.

By using the phosphorus compound of the present invention in combination, a sufficient catalytic effect can be obtained even if the amount of aluminum and cobalt compounds added to the polyester is small. In addition, the heat stability and the low hydrolysis resistance inherent in the polyester containing the cobalt compound are improved by the combined use of the phosphorus compound of the present invention. When the addition amount of the phosphorus compound is less than 0.0001 mol%, the effect of addition may not be exhibited. When the addition amount exceeds 0.1 mol%, on the contrary, the catalytic activity as a polyester polymerization catalyst may decrease. The tendency changes depending on the amount of aluminum used and the like.

When the polyester of the present invention contains one or more metals or metal compounds selected from the group consisting of alkali metals and their compounds, and alkaline earth metals and their compounds, It is preferable because physical properties such as thermal stability are improved. Further, for example, in the case of PET, the use of one or more metals or metal compounds selected from the group consisting of alkali metals and their compounds, and alkaline earth metals and their compounds at the time of production enables the dimerization of ethylene glycol. Since it is possible to reduce the by-product of diethylene glycol (DEG), which is a body, and to suppress the copolymerization of DEG into the polyester, it is possible to prevent a decrease in the physical properties such as a decrease in the softening point of the polyester. In addition to this, when polymerizing the polyester using a specific amount of aluminum compound and cobalt compound as described above, alkali metals and their compounds, and one selected from the group consisting of alkaline earth metals and their compounds Alternatively, it is preferable to add two or more metals or metal compounds because the catalytic activity can be improved. Furthermore, it is preferable to use the above-mentioned specific phosphorus compound in combination, because the catalytic activity can be further improved.

The alkali metal or a compound thereof or an alkaline earth metal or a compound thereof according to the present invention includes, in addition to the alkali metal or the alkaline earth metal,
Li, Na, K, Rb, Cs, Be, Mg, Ca, Sr, Ba is not particularly limited as long as it is one or more compounds selected from the group, for example, formic acid, acetic acid, propionic acid of these metals , Butyric acid, saturated carboxylic acid salts such as oxalic acid, acrylic acid,
Unsaturated aliphatic carboxylate such as methacrylic acid, aromatic carboxylate such as benzoic acid, halogen-containing carboxylate such as trichloroacetic acid, hydroxycarboxylate such as lactic acid, citric acid, salicylic acid, carbonic acid, sulfuric acid, nitric acid , Phosphoric acid, phosphonic acid, hydrogen carbonate, hydrogen phosphate, hydrogen sulfate,
Inorganic acid salts such as sulfurous acid, thiosulfuric acid, hydrochloric acid, hydrobromic acid, chloric acid, and bromic acid; organic sulfonic acid salts such as 1-propanesulfonic acid, 1-pentanesulfonic acid, and naphthalenesulfonic acid; and organic acids such as lauryl sulfuric acid Sulfate, methoxy, ethoxy, n-propoxy, iso-propoxy, n-butoxy, t-
Alkoxides such as butoxy, chelate compounds such as acetylacetonate, oxides, hydroxides and the like, among which saturated aliphatic carboxylate is preferable,
Further, acetate is particularly preferred.

When an alkali metal, an alkaline earth metal or a compound thereof is added, the amount of use M (mol%) is as follows:
It is preferably 1 × 10 ⁻⁶ or more and less than 0.1 mol%, more preferably 5 × 10 ^{−6 to} 0.05 mol%, further preferably, 5 × 10 ^{−6 to} less than 0.1 mol%, based on the number of moles of all the polycarboxylic acid units constituting the polyester. It is 1 × 10 ^{−5 to} 0.03 mol%, particularly preferably 1 × 10 ^{−5 to} 0.01 mol%. Since the added amount of the alkali metal and the alkaline earth metal is small, the reaction rate can be increased without causing problems such as a decrease in thermal stability, generation of foreign matter, and coloring. The amount of alkali metal, alkaline earth metal and compound used is M
When the content is 0.1 mol% or more, there may be a case where a decrease in thermal stability, generation of foreign matter, and an increase in coloring pose a problem in product processing. M
If less than 1 × 10 ⁻⁶ , the effect is not clear even if added.

The production of the polyester according to the present invention can be carried out by a conventionally known method. For example, when manufacturing PET, after esterification of terephthalic acid and ethylene glycol, a method of polycondensation, or after performing an ester exchange reaction between an alkyl ester of terephthalic acid such as dimethyl terephthalate and ethylene glycol, Any of the polycondensation methods can be used. Also,
The polymerization apparatus may be a batch type or a continuous type.

The polyester of the present invention may be produced not only by melt polymerization but also by solid phase polymerization or solution polymerization.

The catalyst used for producing the polyester of the present invention can be added to the reaction system at any stage of the polymerization reaction. For example, addition to the reaction system before the start of the esterification reaction or the transesterification reaction and at any stage during the reaction, or immediately before the start of the polycondensation reaction and at any stage during the reaction is exemplified. In particular, it is preferable to add aluminum or its compound immediately before the start of the polycondensation reaction.

The method of adding an additive such as a catalyst used in the production of the polyester of the present invention may be a powder or neat, a slurry or a solution of a solvent such as ethylene glycol, or the like. There is no particular limitation. A mixture of an aluminum compound and a cobalt compound in advance may be added, or they may be added separately. Further, a mixture of these compounds and a phosphorus compound and / or an alkali metal or a compound thereof or an alkaline earth metal or a compound thereof in advance may be added, or these may be added separately. . Further, these compounds may be added at the same time or at different times.

When an aluminum compound and a cobalt compound are used as a catalyst for producing the polyester of the present invention, the catalyst has catalytic activity not only in polycondensation reaction but also in esterification reaction and transesterification reaction. For example, polymerization by transesterification of an alkyl ester of a dicarboxylic acid such as dimethyl terephthalate with a glycol such as ethylene glycol is usually carried out in the presence of a transesterification catalyst such as a titanium compound or a zinc compound. Alternatively, the catalyst may be used in the presence of these catalysts. Also, the catalyst is
It has catalytic activity not only in melt polymerization but also in solid phase polymerization and solution polymerization, and it is possible to produce polyester by any method.

When the polyester is produced according to the method of the present invention, other polymerization catalysts such as an antimony compound, a titanium compound and a germanium compound are added to the polyester by adding these components to the above-described polyester properties, processability, color tone, etc. The coexistence and use within a range of an addition amount that does not cause a problem in the product is advantageous and preferable in improving productivity by shortening the polymerization time.

However, the content of the antimony compound in the polyester is preferably 50 ppm or less as antimony atoms. It is more preferably at most 30 ppm. If the content of antimony is more than 50 ppm, precipitation of metallic antimony occurs, which causes blackening and foreign matter in the polyester, which is not preferable. The content of the titanium compound in the polyester is preferably 10 ppm or less as a titanium atom. More preferably, it is 5 ppm or less, still more preferably 2 ppm or less. When the content of titanium is more than 10 ppm, the thermal stability of the obtained resin is significantly reduced. The content of the germanium compound in the polyester is 20 as a germanium atom.
It is preferably at most ppm. It is more preferably at most 10 ppm. If the content of germanium is more than 20 ppm, it is not preferable because it is disadvantageous in terms of cost.

In producing the polyester according to the method of the present invention, two or a combination of three or more of an antimony compound, a titanium compound and a germanium compound may be used. However, it is preferable that the total content of antimony, titanium and germanium atoms in the polymer be 50 ppm or less. More preferably, the total content is 40 ppm or less, and still more preferably, the total content is 30 ppm or less. If the total content of antimony, titanium, and germanium atoms in the polyester exceeds 50 ppm, problems such as darkening and foreign matter are generated in the polyester and thermal stability is reduced.

The antimony compound, titanium compound and germanium compound used in the present invention are not particularly limited. Specifically, examples of the antimony compound include antimony trioxide, antimony pentoxide, antimony acetate, antimony glycoside, and the like. Of these, antimony trioxide is preferable. Examples of the titanium compound include tetra-n-butoxytitanate, titanium oxalate, and the like.
Of these, tetra-n-butoxytitanate is preferred. Examples of the germanium compound include germanium dioxide and germanium tetrachloride, among which germanium dioxide is preferable.

In producing a polyester according to the method of the present invention, another polymerization catalyst such as a tin compound can be coexisted within a range that does not impair the thermal stability and color tone of the polyester.

The polyester referred to in the present invention is one or more selected from polycarboxylic acids containing dicarboxylic acids and ester-forming derivatives thereof and one or more selected from polyhydric alcohols containing glycol. Or those composed of hydroxycarboxylic acids and their ester-forming derivatives, or those composed of cyclic esters.

As the dicarboxylic acid, oxalic acid, malonic acid,
Succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, decane dicarboxylic acid, dodecane dicarboxylic acid, tetradecane dicarboxylic acid, hexadecane dicarboxylic acid, 1,3-cyclobutane dicarboxylic acid, 1,3-cyclo Pentanedicarboxylic acid,
Saturated aliphatic dicarboxylic acids exemplified by 1,2-cyclohexanedicarboxylic acid, 1,3-cyclohexanedicarboxylic acid, 1,4-cyclohexanedicarboxylic acid, 2,5-norbornanedicarboxylic acid, dimer acid, and the like, or their ester-forming properties Derivatives, unsaturated aliphatic dicarboxylic acids exemplified by fumaric acid, maleic acid, itaconic acid and the like and ester-forming derivatives thereof, orthophthalic acid, isophthalic acid, terephthalic acid, 5- (alkali metal) sulfoisophthalic acid, diphenic acid 1,3 naphthalenedicarboxylic acid, 1,4 naphthalenedicarboxylic acid, 1,5 naphthalenedicarboxylic acid, 2,6 naphthalenedicarboxylic acid, 2,7 naphthalenedicarboxylic acid, 4,4′-biphenyldicarboxylic acid, 4,4'-biphenylsulfone dicarboxylic acid, 4,4'-biphe Aromatic dicarboxylic acids exemplified by phenyl ether dicarboxylic acid, 1,2-bis (phenoxy) ethane-p, p'-dicarboxylic acid, pamoic acid, anthracene dicarboxylic acid and the like, and ester-forming derivatives thereof, and these dicarboxylic acids Of these, terephthalic acid and naphthalenedicarboxylic acid, particularly 2,6 naphthalenedicarboxylic acid, are preferred.

Examples of the polycarboxylic acids other than these dicarboxylic acids include ethanetricarboxylic acid, propanetricarboxylic acid, butanetetracarboxylic acid, pyromellitic acid, trimellitic acid, trimesic acid, 3,4,3 ′, 4′-biphenyltetracarboxylic acid. Examples include carboxylic acids and their ester-forming derivatives.

As the glycol, ethylene glycol,
1,2-propylene glycol, 1,3-propylene glycol, diethylene glycol, triethylene glycol, 1,2 butylene glycol, 1,3 butylene glycol, 2,3 butylene glycol, 1,4 butylene glycol, 1,5-pentanediol, neopentyl glycol, 1,6-hexanediol, 1,
2-cyclohexanediol, 1,3-cyclohexanediol, 1,4-cyclohexanediol, 1,2-cyclohexanedimethanol, 1,3-cyclohexanedimethanol, 1,4-cyclohexanedimethanol, 1,
Aliphatic glycols exemplified by 4-cyclohexanediethanol, 1,10-decamethylene glycol, 1,12-dodecanediol, polyethylene glycol, polytrimethylene glycol, polytetramethylene glycol, etc., hydroquinone, 4,4'-dihydroxybisphenol 1,4-bis (β-hydroxyethoxy) benzene, 1,4-bis (β-hydroxyethoxyphenyl) sulfone, bis (p-hydroxyphenyl) ether, bis (p-hydroxyphenyl) sulfone, bis (p-hydroxy Phenyl) methane, 1,2-bis (p
-Hydroxyphenyl) ethane, bisphenol A, bisphenol C, 2,5 naphthalene diol, and glycols obtained by adding ethylene oxide to these glycols, and the like. Among these glycols, ethylene glycol and 1 ,
4-butylene glycol is preferred.

Polyhydric alcohols other than these glycols include trimethylolmethane, trimethylolethane,
Trimethylolpropane, pentaerythritol, glycerol, hexanetriol and the like.

Examples of the hydroxycarboxylic acid include lactic acid, citric acid, malic acid, tartaric acid, hydroxyacetic acid, 3-hydroxybutyric acid, p-hydroxybenzoic acid, p- (2-hydroxyethoxy) benzoic acid, 4-hydroxycyclohexanecarboxylic acid, Or, an ester-forming derivative thereof and the like.

Examples of the cyclic ester include ε-caprolactone, β-propiolactone, β-methyl-β-propiolactone, δ-valerolactone, glycolide, lactide and the like.

Examples of the ester-forming derivatives of polycarboxylic acids or hydroxycarboxylic acids include alkyl esters, acid chlorides and acid anhydrides thereof.

The polyester used in the present invention is preferably a polyester whose main acid component is terephthalic acid or its ester-forming derivative or naphthalenedicarboxylic acid or its ester-forming derivative, and whose main glycol component is an alkylene glycol. The polyester in which the main acid component is terephthalic acid or an ester-forming derivative thereof or naphthalenedicarboxylic acid or an ester-forming derivative thereof is referred to as terephthalic acid or an ester-forming derivative thereof and naphthalenedicarboxylic acid or an ester thereof with respect to all the acid components. It is preferable that the polyester contains a total of 70 mol% or more of the active derivative, more preferably a polyester containing 80 mol% or more, and further preferably a polyester containing 90 mol% or more. The polyester in which the main glycol component is an alkylene glycol is preferably a polyester containing 70 mol% or more of alkylene glycol in total with respect to all glycol components, more preferably a polyester containing 80 mol% or more, More preferably, it is a polyester containing 90 mol% or more.
The alkylene glycol mentioned here may contain a substituent or an alicyclic structure in the molecular chain.

The naphthalenedicarboxylic acid or ester-forming derivative thereof used in the present invention includes 1,3 naphthalenedicarboxylic acid, 1,4 naphthalenedicarboxylic acid, 1,5 naphthalenedicarboxylic acid, and 2,6 naphthalenedicarboxylic acid. Acid, 2,7 naphthalene dicarboxylic acid,
Alternatively, these ester-forming derivatives are preferred.

As the alkylene glycol used in the present invention, ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,2-butylene glycol, 1,3-butylene glycol, 2,
3-butylene glycol, 1,4-butylene glycol, 1,5-pentanediol, neopentyl glycol, 1,6-hexanediol, 1,2-cyclohexanediol, 1,3-cyclohexanediol, 1,4-cyclohexanediol, 1,2-cyclohexanedimethanol, 1,3-cyclohexanedimethanol, 1.4
-Cyclohexanedimethanol, 1,4-cyclohexanediethanol, 1,10-decamethylene glycol,
1,12-dodecanediol and the like. Two or more of these may be used simultaneously.

The polyester of the present invention contains oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, as acid components other than terephthalic acid or its ester-forming derivative, naphthalenedicarboxylic acid or its ester-forming derivative. Suberic acid, azelaic acid, sebacic acid, decanedicarboxylic acid, dodecanedicarboxylic acid, tetradecanedicarboxylic acid, hexadecanedicarboxylic acid,
1,3-cyclobutanedicarboxylic acid, 1,3-cyclopentanedicarboxylic acid, 1,2-cyclohexanedicarboxylic acid, 1,3-cyclohexanedicarboxylic acid, 1,4-cyclohexanedicarboxylic acid, 2,5-norbornanedicarboxylic acid, dimer Saturated aliphatic dicarboxylic acids exemplified by acids and the like and ester-forming derivatives thereof, fumaric acid, maleic acid, unsaturated aliphatic dicarboxylic acids exemplified by such as itaconic acid and the like and ester-forming derivatives thereof, orthophthalic acid, isophthalic acid Acid, 5- (alkali metal) sulfoisophthalic acid, diphenic acid, 4,4'-biphenyldicarboxylic acid, 4,4'-biphenylsulfonedicarboxylic acid, 4,4'-biphenyletherdicarboxylic acid, 1,2-bis (phenoxy ) Ethane-p, p'-dicarboxylic acid, pamoic acid, anthra Aromatic dicarboxylic acids exemplified by sendicarboxylic acid or ester-forming derivatives thereof, ethanetricarboxylic acid, propanetricarboxylic acid, butanetetracarboxylic acid, pyromellitic acid, trimellitic acid, trimesic acid, 3,4,3 ′ ,
Polycarboxylic acids exemplified by 4′-biphenyltetracarboxylic acid and the like and ester-forming derivatives thereof can be contained as copolymer components. Also, hydroxycarboxylic acids exemplified by lactic acid, citric acid, malic acid, tartaric acid, hydroxyacetic acid, 3-hydroxybutyric acid, p-hydroxybenzoic acid, p- (2-hydroxyethoxy) benzoic acid, 4-hydroxycyclohexanecarboxylic acid and the like Alternatively, an ester-forming derivative thereof may be included. Also, ε-caprolactone, β-propiolactone,
β-methyl-β-propiolactone, δ-valerolactone,
Cyclic esters exemplified by glycolide, lactide and the like can also be included.

In the polyester of the present invention, as glycol components other than the alkylene glycol, aliphatic glycols exemplified by diethylene glycol, triethylene glycol, polyethylene glycol, polytrimethylene glycol, polytetramethylene glycol, etc., hydroquinone, 4,4 'Dihydroxybisphenol,
1,4-bis (β-hydroxyethoxy) benzene, 1,
4-bis (β-hydroxyethoxyphenyl) sulfone, bis (p-hydroxyphenyl) ether, bis (p-hydroxyphenyl) sulfone, bis (p-hydroxyphenyl) methane, 1,2-bis (p-hydroxyphenyl) ethane, Bisphenol A, bisphenol C, 2,5 naphthalene diol, aromatic glycols exemplified by glycols obtained by adding ethylene oxide to these glycols, trimethylolmethane, trimethylolethane, trimethylolpropane, pentaerythritol, glycerol, hexane A polyhydric alcohol exemplified by triol or the like can be contained as a copolymer component.

The polyester of the present invention includes polyethylene terephthalate, polybutylene terephthalate, polypropylene terephthalate, poly (1,4-cyclohexane dimethylene terephthalate), polyethylene naphthalate, polybutylene naphthalate, polypropylene naphthalate and copolymers thereof. Of these, polyethylene terephthalate and its copolymer are particularly preferred.

The polyester of the present invention can contain a known phosphorus compound as a copolymer component. As the phosphorus compound, a bifunctional phosphorus compound is preferable, for example, (2-carboxylethyl) methylphosphinic acid,
(2-carboxyethyl) phenylphosphinic acid, 9,
10-dihydro-10-oxa- (2,3-carboxypropyl) -10-phosphaphenanthrene-10-oxide and the like. By including these phosphorus compounds as copolymer components, it is possible to improve the flame retardancy and the like of the obtained polyester. As a component of the polyester of the present invention, it is a preferred embodiment to use a polycarboxylic acid having a sulfonate alkali metal base as a copolymer component in order to improve the dyeability when the polyester is used as a fiber. The metal sulfonate group-containing compound used as the copolymerization monomer is not particularly limited, but is not particularly limited to 5-sodium sulfoisophthalic acid, 2-sodium sulfoterephthalic acid, 5-lithium sulfoisophthalic acid, 2-lithium sulfoterephthalic acid, Examples thereof include 5-potassium sulfoisophthalic acid, 2-potassium sulfoterephthalic acid, and lower alkyl ester derivatives thereof. In the present invention, use of 5-sodium sulfoisophthalic acid or an ester-forming derivative thereof is particularly preferred. The copolymerization amount of the metal sulfonate group-containing compound is 0.
It is preferably from 3 to 10.0 mol%, more preferably from 0.80 to 5.0 mol%. If the copolymerization amount is too small, the dyeability of the basic dye is inferior. If the copolymerization amount is too large, not only the spinning properties are poor, but also the fiber does not have sufficient strength due to the thickening phenomenon. Further, when 2.0 mol% or more of the metal sulfonate-containing compound is copolymerized, it is possible to impart normal pressure dyeability to the obtained modified polyester fiber. It is possible to appropriately reduce the amount of the metal sulfonate group-containing compound by selecting an appropriate dye for facilitating dyeing.
Examples of the easily dyeable monomer include, but are not particularly limited to, long-chain glycol compounds represented by polyethylene glycol and polytetramethylene glycol, and aliphatic dicarboxylic acids represented by adipic acid, sebacic acid, and azelaic acid. After the polyester polymerization according to the method of the present invention, the thermal stability of the polyester can be further increased by removing the catalyst from the polyester or deactivating the catalyst by adding a phosphorus compound or the like. The polyester of the present invention may contain organic, inorganic, and organometallic toners, a fluorescent whitening agent, and the like. By containing one or more of these, the polyester becomes yellowish. Etc. can be suppressed to a more excellent level. Also, any other polymer, antistatic agent, defoamer, dyeability improver, dye,
Pigments, matting agents, optical brighteners, stabilizers, antioxidants and other additives may be included. As the antioxidant, an aromatic amine type, a phenol type or the like antioxidant can be used, and as the stabilizer, a phosphorus type such as phosphoric acid or a phosphoric ester type, a sulfur type, an amine type or the like can be used. Can be used.

[0057]

EXAMPLES The present invention will be described below with reference to examples, but the present invention is not limited to these examples. In each of the examples and comparative examples, the intrinsic viscosity (IV) of the polyester was measured as follows. The measurement was carried out at a temperature of 30 ° C. using a 6/4 mixed solvent (weight ratio) of phenol / 1,1,1,2,2-tetrachloroethane.

Analysis of metal content: The metal content was determined by high-frequency plasma emission analysis and atomic absorption analysis after ashing / dissolving the polymer.

Evaluation method of thermal stability: 2.5 g of PET was placed in a glass test tube, vacuum-dried at 130 ° C. for 12 hours, kept in a nitrogen atmosphere at 300 ° C. for 5 hours, cooled at room temperature, and treated. Later PET was taken out. Next, the removed PET was formed into a film by a heat press machine. The obtained film was cut into a test piece having a length of 8 cm and a width of 4 cm, and the obtained film was pulled in the length direction to evaluate the cutability. Those that were hard to cut were evaluated as good. The evaluation index is represented by the following symbols. ◎: extremely good, ○: good △: slightly poor, ×: bad

Evaluation method of color tone: Polyester resin chips obtained by polymerization were formed into a film by a heat press machine, and then the degree of coloring (yellowish and blackish) of the polyester was visually checked. The color index is represented by the following symbols. ◎: almost no coloring, ○: slightly colored △: slightly colored, ×: markedly colored

Evaluation method of hydrolysis resistance: PET was formed into a film by a heat press machine, and the obtained film was cut into a test piece having a length of 8 cm and a width of 4 cm. The obtained film and 100 ml of water were placed in a cylindrical container having an inner diameter of 6 cm and a height of 11 cm, sealed, and heat-treated in a glycerin bath at 140 ° C. for 6 hours. Then, the film taken out was dried under reduced pressure at 80 ° C. for 12 hours, and then the film was pulled in the length direction, and the hydrolysis resistance was evaluated by the easiness of cutting. Those that were hard to cut were evaluated as good. The evaluation index is represented by the following symbols. ◎: extremely good, ○: good △: slightly poor, ×: bad

(Example 1) Bis (2-
To a mixture of (hydroxyethyl) terephthalate and oligomer, as a catalyst, a solution of 3 g / l of ethylene glycol in aluminum chloride was added as an aluminum atom to the finally obtained polymer at 40 ppm as an aluminum atom, and 10 g / l of ethylene glycol in cobalt acetate tetrahydrate was added. The solution is 3 ppm as cobalt atoms with respect to the polymer finally obtained.
Then, add 10 g / l of dimethyl phenylphosphonate.
An ethylene glycol solution was added at 0.01 mol% to the acid component in the polyester, and 5% of lithium acetate dihydrate was added.
g / l ethylene glycol solution was added at 0.025 mol% based on the acid content in the polyester,
For 10 minutes. Next, it took 50 minutes to gradually raise the temperature of the reaction system to 275 ° C while gradually lowering the pressure to 13.3 Pa.
The polycondensation reaction was performed at 275 ° C. and 13.3 Pa for 3 hours. Table 1 shows the physical properties of the obtained polymer, the metal content in the polymer, and the evaluation results of thermal stability, color tone, and hydrolysis resistance.

(Examples 2 to 7 and Comparative Examples 1 to 3) A polyester was polymerized in exactly the same manner as in Example 1 except that the catalyst was changed. Table 1 shows the physical properties of the obtained polymer, the metal content in the polymer, and the evaluation results of thermal stability, color tone, and hydrolysis resistance.

[0064]

[Table 1]

[0065]

According to the present invention, there is provided a polyester which is polymerized by using other than an antimony compound and a germanium compound as a main component of a catalyst and is excellent in heat stability, color tone and hydrolysis resistance. The polyester of the present invention can be applied to fibers for clothing, fibers for industrial materials, various films, sheets, various molded products such as bottles and engineering plastics, and paints and adhesives.

Continuation of the front page F term (reference) 4J029 AA03 AB01 AB04 AB07 AC01 AD10 AE01 AE02 AE03 BA03 CB06A HA01 HB01 HB03A JA061 JA091 JA121 JA161 JA201 JA261 JA281 JB131 JB151 JB171 JB271 JC371 JC571 JF01FJFJF1FJF1FJF1FJF1F JF361 JF471 JF571 KE02 KE03

Claims (5)

[Claims] 1. A polyester comprising aluminum and / or a compound thereof and cobalt and / or a compound thereof and having a content satisfying the following formulas (1) and (2). Co ≦ 4 (ppm) (1) 0.5 ≦ Al / Co ≦ 45 (2) (In the formulas (1) and (2), Al and Co are the contents of aluminum atoms and cobalt atoms contained in the polyester, respectively. (Ppm).) 2. The polyester according to claim 1, which contains at least one compound represented by the following general formulas (1) and (2). Embedded image (In the formula, R ¹ and R ² each independently represent hydrogen, an alkyl group having 1 to 50 carbon atoms, or an aryl group.) (In the formula, R ³ and R ⁴ each independently represent hydrogen, an alkyl group having 1 to 50 carbon atoms, or an aryl group.) 3. The method according to claim 1, which comprises one or more metals and / or metal compounds selected from the group consisting of alkali metals and their compounds, and alkaline earth metals and their compounds. 3. The polyester according to any of 2. 4. An antimony, titanium and germanium content satisfying the following formulas (3) to (6).
Polyester according to any one of claims 1 to 3. Sb ≦ 50 (ppm) (3) Ti ≦ 10 (ppm) (4) Ge ≦ 20 (ppm) (5) Sb + Ti + Ge ≦ 50 (ppm) (6) (Sb, Ti and Ge are antimony contained in the polyester, respectively.) The contents (ppm) of atoms, titanium atoms, and germanium atoms are shown.) 5. A method for producing a polyester, comprising using the substance according to claim 1 and the amount of the substance contained in the polyester according to claim 1 as a polymerization catalyst.