JP4844088B2 - Polyester polycondensation catalyst and method for producing polyester resin using the same - Google Patents

Description

  The present invention relates to a polyester polycondensation catalyst, a polyester polycondensation catalyst solution containing the polyester polycondensation catalyst, a polyester polycondensation catalyst or a method for producing a polyester resin using the solution, and the production of the polyester resin. The present invention relates to a polyester resin obtained by the method and various molded articles obtained from the polyester resin.

  Since polyester resins are excellent in chemical and physical properties, they have been widely used in various applications such as containers such as bottles, films, sheets, and fibers.

  In general, a polyester resin undergoes an esterification reaction or transesterification reaction between a dicarboxylic acid and / or an ester-forming derivative thereof and a diol, and a melt polycondensation reaction. It is produced by a condensation reaction. In the polycondensation reaction, compounds such as antimony, germanium, and titanium are used as catalysts.

  However, in the case of a polyester resin using an antimony compound as a catalyst, is it possible to reduce the amount of antimony compound used due to its unique dullness, safety and hygiene concerns about the antimony compound, and consideration for the environment? The emergence of an alternative polycondensation catalyst has been strongly desired. In addition, the polyester resin using a germanium compound as a catalyst is suitable in terms of transparency and safety and hygiene, but the germanium compound itself is extremely expensive and the economical disadvantage cannot be avoided. In addition, there has been a strong demand for the appearance of a polycondensation catalyst to reduce the amount used or to replace it.

  On the other hand, titanium compounds are attracting attention because they are inexpensive and have no concern for safety and health, and have been used in place of antimony compounds and germanium compounds. Further, it had a peculiar yellowish color and further had defects in quality such as poor thermal stability.

  On the other hand, Patent Document 1 proposes a method for producing a polyester resin having excellent quality by dividing each of titanium, magnesium and phosphorus compounds as an ethylene glycol solution and adding them at a specific ratio. Yes. However, this method requires at least three independent catalyst addition devices, and it is not easy to divert polyester resin production facilities such as conventional antimony catalysts, and it is necessary to add new facilities. It becomes.

  Accordingly, a polyester polycondensation catalyst that contains titanium atoms, alkaline earth metal atoms such as magnesium, and phosphorus atoms in the same catalyst, and that can stably use the conventionally used polyester resin production equipment is desired. It was rare.

  As such a polyester polycondensation catalyst, Patent Document 2 discloses a catalyst comprising an alkyl titanate treated with an aromatic polycarboxylic acid, a magnesium compound, a specific phosphorus compound, and ethylene glycol. According to the study by the inventors, the catalyst lacks long-term stability in ethylene glycol, becomes cloudy after being stored for several days, and deposits of metal components are seen to form a slurry. Since the catalyst is in a slurry state, it is difficult to accurately add to the polycondensation reaction of the polyester, and the slurry catalyst settles and scales in the catalyst storage tank or the catalyst addition line. It was found that there was a problem of poor handling. In addition, in order to prepare the catalyst, it is indispensable to treat the titanium compound with an aromatic polyvalent carboxylic acid, and there is a problem that the manufacturing process is complicated and the cost is increased accordingly. Furthermore, the necessity of a heating step of 100 ° C. or higher is not easy in practice.

  Patent Document 3 discloses a homogeneous solution catalyst containing a titanium atom and a group 2A metal atom of the periodic table in ethylene glycol or the like. Patent Document 3 discloses that an organic acid or an inorganic acid is added to a solution in order to make the solution acidic for the purpose of stabilizing the turbidity of the homogeneous solution catalyst at a low level. It is not disclosed at all that a phosphorus compound to be added and used in the resin production reaction is added to the homogeneous solution, and it is necessary to separately add a phosphorus compound as a stabilizer for the polyester resin during the production of the polyester resin.

  Patent Document 4 discloses a method in which a solid titanium compound or a solid titanium compound containing magnesium is synthesized in advance and an ethylene glycol solution containing titanium and magnesium atoms as a catalyst is used as a catalyst. ing. However, this technique has a problem that the process for producing the catalyst is complicated, such as requiring a process for hydrolyzing the metal compound, and the cost is increased accordingly. Moreover, it is not disclosed at all that a phosphorus compound to be added and used in the polyester production reaction is added to the ethylene glycol solution, and it is necessary to add a phosphorus compound separately during the polyester production.

On the other hand, the present inventors include a titanium atom, an alkaline earth metal atom, and a phosphorus atom in Patent Document 5, which is a prior application, and are industrially easy to manufacture and low in cost. A liquid polyester polycondensation catalyst having excellent storage stability and a method for producing the same were proposed. However, the liquid catalyst of the present invention is bulky because of the relatively low concentration of titanium atoms contained therein, and contains a large amount of solvent.
JP 2004-124068 A JP 2004-224858 A JP 2004-292803 A JP 2004-176033 A Japanese Patent Application No. 2005-014379

  The present invention solves the above-mentioned conventional problems, including a titanium atom, an alkaline earth metal atom, and a phosphorus atom, has a high concentration of a catalytic active component, is excellent in long-term storage stability, and industrially. To provide a solid or liquid polyester polycondensation catalyst that is easy to produce and advantageous in terms of cost, a polyester resin excellent in quality such as hue using the catalyst, a production method thereof, and various molded articles. Objective.

The polyester polycondensation catalyst of the present invention is a polyester polymerization catalyst containing a titanium atom, an alkaline earth metal atom, a phosphorus atom and a carbon atom,
At least some of the carbon atoms are derived from organic acids and / or carboxylates;
The content T (weight basis) of titanium atoms is 4 to 20% by weight,
Organic acid and / or carboxylate content L (molar basis), alkaline earth metal atom content M (molar basis), titanium atom content T (weight basis), phosphorus atom content P (molar basis) And a carbon atom content C (by weight) satisfying the following formulas (1), (2) and (3) (claim 1).
0.8 ≦ L / M (molar ratio) ≦ 1.8 (1)
0.05 ≦ T / C (weight ratio) ≦ 0.50 (2)
0.5 ≦ M / P (molar ratio) ≦ 3.0 (3)

This polyester polycondensation catalyst is preferably obtained by mixing an alcohol, a titanium compound, an alkaline earth metal compound, and an acidic phosphate compound, and concentrating the mixture (claim 2). The ratio W ₁ / W ₀ between the weight W _{1 of the} polyester polycondensation catalyst and the total weight W ₀ of the titanium compound, alkaline earth metal compound, and acidic phosphate compound used for mixing is 0.45 or more. The alkaline earth metal compound is preferably an organic acid salt of alkaline earth metal and / or a hydrate thereof (claim 4).

（式中、Ｔはチタン原子、Ｍはアルカリ土類金属原子、Ｏは酸素原子、Ｐはリン原子、Ｒ^１は炭素数１以上６以下のアルキル基、シクロヘキシル基、アリール基又は２−ヒドロキシエチル基であり、Ｒ^２は炭素数１〜３のアルキル基である。） The polyester polycondensation catalyst of the present invention preferably contains a basic structure represented by the following general formula (III) (Claim 5).

Wherein T is a titanium atom, M is an alkaline earth metal atom, O is an oxygen atom, P is a phosphorus atom, R ¹ is an alkyl group having 1 to 6 carbon atoms, a cyclohexyl group, an aryl group, or 2-hydroxyethyl And R ² is an alkyl group having 1 to 3 carbon atoms.)

  The polyester polycondensation catalyst of the present invention is preferably a solid (claim 6).

  The polyester polycondensation catalyst solution of the present invention contains a polyester polycondensation catalyst and ethylene glycol and / or 1,4-butanediol (Claim 7).

  The polyester polycondensation catalyst solution of the present invention comprises a polyester polycondensation catalyst, water, ethylene glycol and / or 1,4-butanediol, and the water content is 0.01 to 10% by weight. The titanium atom content (by weight) is preferably 300 to 100,000 ppm and is preferably liquid.

  The polyester polycondensation catalyst solution of the present invention is preferably prepared by mixing an alcohol, a titanium compound, an alkaline earth metal compound, and an acidic phosphate ester compound, and concentrating the mixture to a liquid substance obtained by adding ethylene glycol and It is obtained after mixing 1,4-butanediol and further distilling a substance having a lower boiling point than ethylene glycol and / or 1,4-butanediol (Claim 9).

  The polyester resin production method of the present invention uses the polyester polycondensation catalyst of the present invention and / or the polyester polycondensation catalyst solution of the present invention (claim 10).

  The polyester resin of the present invention is obtained by such a method for producing a polyester resin of the present invention (claim 11).

The present invention also provides such Ru obtained from the polyester resin of the present invention, the hollow moldings, films, and gist fibers or hollow molded body preform (claim 12).

  According to the present invention, it does not contain compounds such as antimony and germanium, contains titanium atoms, alkaline earth metal atoms, and phosphorus atoms, has a high concentration of catalytically active components, has excellent long-term storage stability, and is industrially produced. A solid or liquid polyester polycondensation catalyst that is easy and cost-effective is provided, and a polyester resin excellent in quality such as color tone is industrially advantageously produced using the polyester polycondensation catalyst. It becomes possible to do.

  Thus, the preform obtained from the polyester resin of the present invention has little change in the crystallization temperature Tc1 even when it absorbs moisture, and can widen the preform temperature range for obtaining a transparent bottle, and can be stably produced. is there.

Embodiments of the present invention will be described in detail below. However, the description of the constituent elements described below is a representative example of the embodiments of the present invention, and the present invention includes these contents as long as the gist thereof is not exceeded. It is not limited.
In the present specification, “ppm” and “%” mean “weight ppm” and “wt%” unless otherwise specified as “mol” or the like.

<Polyester polycondensation catalyst>
The polyester polycondensation catalyst of the present invention contains a titanium atom, an alkaline earth metal atom, a phosphorus atom, and a carbon atom, and at least a part of the carbon atom is derived from an organic acid and / or a carboxylate. The titanium atom content T (weight basis) is 4 to 20% by weight, the organic acid and / or carboxylate content L (molar basis), the alkaline earth metal atom content M (molar basis) ), Titanium atom content T (weight basis), carbon atom content C (weight basis), phosphorus atom content P (molar basis) are represented by the following formulas (1), (2), and (3): It is a solid or liquid substance satisfying the above.
0.8 ≦ L / M (molar ratio) ≦ 1.8 (1)
0.05 ≦ T / C (weight ratio) ≦ 0.50 (2)
0.5 ≦ M / P (molar ratio) ≦ 3.0 (3)

Examples of the organic acid and / or carboxylate constituting at least part of the carbon atoms contained in the polycondensation catalyst of the present invention include aliphatic carboxylic acids and aliphatic carboxylates, and among them, fatty acids having 1 to 4 carbon atoms. Preferred are aliphatic carboxylic acids and aliphatic carboxylates having 1 to 4 carbon atoms, and in particular, the solubility of the catalyst in the polyester resin raw material glycol such as ethylene glycol and 1,4-butanediol is excellent. (CH ₃ COOH) and acetate (CH ₃ COO ⁻ ) are particularly preferred.

  If the content T (weight basis) of the titanium atom in the polycondensation catalyst of the present invention is less than the above lower limit, the polycondensation reaction rate during the polycondensation reaction tends to decrease. Speed may not be obtained. When the upper limit is exceeded, the polycondensation reaction rate is sufficient, but the color tone and thermal stability of the resulting polyester resin tend to be reduced. The titanium atom content T in the polycondensation catalyst is preferably 4.5% by weight or more, more preferably 5.5% by weight or more, and preferably 16% by weight or less, more preferably 14% by weight or less.

  In the formula (1), if L / M exceeds the upper limit value, the catalyst activity is lowered, and if it is less than the lower limit value, the solubility of the catalyst in the glycol of the polyester resin raw material becomes small, which is inconvenient in practical use. The upper limit of L / M is preferably 1.7, more preferably 1.6, and the lower limit is preferably 0.8, more preferably 1.0.

  In the formula (2), even if T / C exceeds the upper limit value or less than the lower limit value, the solubility of the catalyst in the glycol of the polyester resin raw material such as ethylene glycol or 1,4-butanediol becomes small, which is inconvenient in practical use. It is. The upper limit of T / C is preferably 0.40, more preferably 0.30, and the lower limit is preferably 0.15, more preferably 0.20.

  In the formula (3), if M / P exceeds the upper limit value, the thermal stability of the polyester resin obtained using this catalyst is deteriorated, which is not preferable. Moreover, the catalyst stability in the glycol of the polyester resin raw material also deteriorates, and an alkaline earth metal may precipitate. A catalyst activity falls that M / P is less than a lower limit. The upper limit of M / P is preferably 1.8, more preferably 1.5, and the lower limit is preferably 0.9, more preferably 1.1.

<Method for producing polyester polycondensation catalyst>
Next, the manufacturing method of the catalyst for polyester polycondensation of this invention is demonstrated.
The polycondensation catalyst of the present invention can be preferably produced by mixing an alcohol, a titanium compound, an alkaline earth metal compound, and an acidic phosphate compound and concentrating the mixture. More details
(i) Step of mixing, dissolving, and reacting alcohol, titanium compound, alkali metal compound and acidic phosphate compound
(ii) A step of concentrating by distilling off alcohol etc. from the reaction solution obtained in step (i) and further proceeding with the reaction to obtain a viscous liquid catalyst, solid catalyst, or a mixture thereof. Manufactured by. At this time, it is considered that the alcohol used does not participate in the reaction but only serves as a solvent.

  The difference between the viscous liquid catalyst, the solid catalyst, or a mixture thereof and the resulting catalyst is due to the degree of concentration. The catalyst obtained in step (ii) can be easily recovered as it is or after being dissolved in glycol such as ethylene glycol or 1,4-butanediol. In addition, what is distilled off at the time of concentration is an alcohol, an organic acid, or the like by-produced by a reaction between an alcohol used as a solvent, a titanium compound, an alkaline earth metal compound, and an acidic phosphate compound.

Therefore, the weight of the polyester polycondensation catalyst obtained by the present invention is always less than the total weight of the raw materials excluding the alcohol used as the solvent. The sum of the weight W _{1 of the} resulting polyester polycondensation catalyst and the weight of the titanium compound, alkaline earth metal compound, and acidic phosphate compound used for mixing, that is, mixed with alcohol in the step (i). W ratio _W 1 / _{W 0} of ₀ is usually 0.45 to 0.85. This ratio varies depending on the type of raw material compound used and the composition ratio.

  The alcohol used for producing the polycondensation catalyst of the present invention may be any alcohol as long as it becomes a homogeneous solution by mixing a titanium compound, an alkaline earth metal compound, and an acidic phosphate ester compound. Among them, methanol, Monohydric alcohols such as ethanol, butanol, propanol, and 2-ethylhexanol are preferably used because of the solubility of the compound and ease of handling. These alcohols may be used alone or in combination of two or more. In particular, ethanol is preferred because the titanium compound, alkaline earth metal compound, and acidic phosphate compound have high solubility and have a low boiling point when the reaction solution is concentrated and are easy to remove.

  Further, as titanium compounds, tetra-n-propyl titanate, tetra-i-propyl titanate, tetra-n-butyl titanate, tetra-n-butyl titanate tetramer, tetra-t-butyl titanate, acetyl-tri-i-propyl Examples thereof include tetraalkoxy titanates such as titanate and titanium acetate, among which tetra-i-propyl titanate and tetra-n-butyl titanate are preferable, and tetra-n-butyl titanate is particularly preferable. These titanium compounds may be used individually by 1 type, and may use 2 or more types together.

  As the alkaline earth metal compound, an organic acid salt of alkaline earth metal and / or a hydrate thereof is preferably used. Among them, preferred compounds include organic acid salts such as magnesium and calcium, and / or hydrates thereof. Magnesium compounds are preferred from the viewpoint of catalytic activity. Examples of the magnesium compound include organic acid salts such as magnesium acetate and magnesium lactate. Magnesium acetate and / or hydrates thereof are particularly preferable because of high solubility in alcohol and easy preparation of the catalyst. . These alkaline earth metal compounds may be used alone or in combination of two or more. Also, different metal compounds such as magnesium compounds and calcium compounds can be used in combination.

  As the acidic phosphate compound, those having an ester structure of phosphoric acid having at least one hydroxyl group represented by the following general formula (I) and / or (II) are preferably used.

（式中、Ｒ、Ｒ’、Ｒ”は各々炭素数１以上６以下のアルキル基、シクロヘキシル基、アリール基又は２−ヒドロキシエチル基を表し、式（Ｉ）において、ＲとＲ’は同一であっても異なっていてもよい。）

(Wherein R, R ′ and R ″ each represent an alkyl group having 1 to 6 carbon atoms, a cyclohexyl group, an aryl group or a 2-hydroxyethyl group. In formula (I), R and R ′ are the same. It may or may not be.)

  Specific examples of such acidic phosphoric acid ester compounds include methyl acid phosphate, ethyl acid phosphate, isopropyl acid phosphate, butyl acid phosphate, octyl acid phosphate, and the like, and ethyl acid phosphate and butyl acid phosphate are preferred. These acidic phosphate ester compounds may be used alone or in combination of two or more.

There are monoester (II) and diester (I) as acidic phosphoric acid ester compounds, but monoester or a mixture of monoester and diester containing 30% by weight or more of monoester is used. In this mixture, the proportion of the monoester is more preferably 40% by weight or more. As the monoester body, a monoethyl ester body or a monobutyl ester body is preferably used.
Further, in addition to the monoester (II) and diester (I), normal phosphoric acid may be contained as an impurity in an amount of 5 to 20% by weight.

  Below, ethanol as an alcohol that acts as a solvent, tetra-n-butyl titanate as a titanium compound, magnesium acetate tetrahydrate as a magnesium compound, ethyl acid phosphate as an acidic phosphate compound (monoester and diester) The method for producing the polyester polycondensation catalyst of the present invention will be described more specifically by taking as an example the case of using a mixing weight ratio of 1: 1.22).

  In step (i), ethanol and a raw material compound are charged into a reaction vessel equipped with a raw material inlet, a stirrer, and the like, and are stirred and mixed for reaction. The reaction is carried out under mild conditions, for example, 10 to 80 ° C. under normal pressure, preferably 20 to 50 ° C. and 5 to 60 minutes to make a uniform transparent solution (step (i)). After visually confirming that the reaction solution has become transparent, the solvent is distilled off under reduced pressure to concentrate the reaction solution (step (ii)). Concentration is usually carried out at a temperature of 150 ° C. or less, preferably 120 ° C. or less, particularly preferably 100 ° C. or less, using a general distillation apparatus, evaporator, conical dryer, spray dryer, centrifugal thin film concentrator, cracks dryer or the like. The In addition, it can be carried out by adding a decompression equipment equipped with a distillation pipe to the reactor of step (i) as long as a viscous liquid is obtained without performing high concentration. The device can be simplified.

  In the initial stage of the concentration step (ii), the alcohol that mainly functions as a solvent is distilled off. In the latter stage of concentration, acetic acid derived from magnesium acetate, water, and butanol derived from tetra-n-butyl titanate are distilled. In this way, in the state where 90% or more of the alcohol that has acted as a solvent is distilled off, a viscous liquid is formed, and this viscous liquid catalyst gradually becomes a dense liquid as the concentration proceeds. And a solid (powder) catalyst produced on the surface of the catalyst, and when the concentration further proceeds, the catalyst becomes a solid catalyst.

In the solid catalyst obtained in such a concentration step, a mass reduction of 30 to 50% by weight is usually observed with respect to the total weight of the mixed raw material compounds (that is, W ₁ / W ₀ = 0. 5 to 0.7, hereinafter, the reduction ratio of the weight of the obtained polycondensation catalyst with respect to the total weight of the mixed raw material compounds may be referred to as “weight reduction ratio during production”.

  The solid catalyst mainly contains 1 to 20% by weight of butanol and contains 0.8 to 1.5 moles of acetic acid (acetate) coordinated with magnesium with respect to the number of moles of magnesium metal. Thus, the highly concentrated solid catalyst has extremely advantageous characteristics with respect to transportability and storage stability.

The obtained solid catalyst can be handled in the air, does not show adhesion to the reactor and glass products, and is soluble in water, so the reactor can be easily washed with water. .
The catalyst is preferably stored in a sealed container, and particularly preferably stored at room temperature in a sealed state after the inside of the container is replaced with an inert gas such as nitrogen. Under such an inert gas atmosphere, storage for one year or more is possible.

  The polycondensation catalyst of the present invention can be handled as a viscous liquid before being isolated as a solid catalyst, and can be used as it is as a polycondensation catalyst. With this viscous liquid catalyst, a weight loss of 20 to 10% by weight is observed during production.

  In order to reduce the viscosity of such a viscous liquid and make it easier to handle, the polycondensation catalyst of the present invention is obtained by dissolving and diluting with a glycol that is a polyester resin raw material such as ethylene glycol. It can also be stored stably as a solution for a long time without producing precipitates.

  Usually, the titanium atom concentration after dilution of such a viscous liquid polycondensation catalyst with a polyester resin raw material glycol such as ethylene glycol is 10,000 to 100,000 ppm by weight, preferably 20,000 to 50,000. 000 ppm by weight. Such a catalyst solution can be further diluted to about 10 to 500 times in a catalyst preparation tank. By diluting in this way, it becomes possible to stably supply a certain amount of a low concentration catalyst into the reaction system.

<Method for producing glycol solution of polyester polycondensation catalyst>
The solid or liquid polyester polycondensation catalyst of the present invention is directly applied to a glycol as a polyester resin raw material such as ethylene glycol and / or 1,4-butanediol (hereinafter sometimes referred to as “glycol”). It can be easily dissolved and used industrially as the catalyst diluent.

  Further, after the reaction liquid obtained in the step (i) is concentrated by distilling monovalent alcohol in an amount less than the total amount, for example, 70% by weight or more, preferably 85 to 95% by weight of the total amount, A step of distilling off low-boiling substances such as alcohol from the mixture of the alcohol, titanium compound, alkaline earth metal compound, acidic phosphate ester and glycol by distillation, that is, the solvent alcohol By substituting glycol, a catalyst solution containing high concentrations of titanium, alkaline earth metal, and phosphorus is produced. By this method, it is possible to easily produce a concentrated glycol solution of the catalyst without going through a solid catalyst.

  In this case, in order to efficiently replace alcohol with glycol by distillation, the alcohol used preferably has a boiling point difference of 50 ° C. or more and a large boiling point difference among glycols, among the monovalent alcohols described above. It is preferable to use an alcohol having a relatively low boiling point such as methanol, ethanol, propanol, or butanol. These alcohols may be used alone or in combination of two or more.

  Thus, in the method of replacing an alcohol solvent and glycol without passing through a solid or viscous liquid polycondensation catalyst, the titanium atom concentration is 10,000 to 100,000 ppm, preferably 20,000 to A 50,000 ppm catalyst solution can be prepared.

  A catalyst solution having a high titanium concentration obtained through the above-described solid or viscous liquid polycondensation catalyst, or a catalyst solution having a high titanium concentration obtained by replacing the alcohol solvent and glycol as described above. Is excellent in storage stability and transportability, and can be further diluted with a polyester resin raw material glycol such as ethylene glycol when the catalyst is used. When the catalyst is used, the titanium atom concentration of the catalyst solution is 300 to 10,000 ppm, preferably 400 to 5,000 ppm, and more preferably 500 to 3,000 ppm.

  The liquid polycondensation catalyst or catalyst solution of the present invention can also be handled in the air, but it is preferably stored in an inert gas atmosphere for long-term storage for a few months or more.

  The pH of the glycol solution of the polycondensation catalyst of the present invention is usually 7 or less, 3 or more, preferably 6.5 or less, 4 or more, more preferably 6.0 or less, 5.0 or more. If the pH exceeds 7.0, the metal tends to precipitate, and if the pH is less than 4.0, the catalyst may change into a gel state with time and the apparatus may be corroded. Therefore, in order to be in such a pH range, in the glycol solution as necessary, a phosphorous compound exhibiting acidity, in particular, the above-mentioned acidic phosphoric acid ester compound, aliphatic carboxylic acid such as acetic acid, alkaline earth metal compound, etc. It is preferable to prepare using

  The polycondensation catalyst of the present invention preferably contains a small amount of water when it needs to be dissolved in a glycol such as ethylene glycol and stored. In this case, the preferred water content is preferably 10% by weight or less, more preferably 5% by weight or less, and particularly preferably 1.5% by weight or less as the weight concentration of the polycondensation catalyst with respect to the entire glycol solution. Moreover, 0.01 weight% or more is preferable, More preferably, it is 0.1 weight% or more, Especially 0.5 weight% or more is preferable. If the water content exceeds the above upper limit, the titanium compound reacts with water and gels, and it tends to be difficult to obtain a uniform solution. Further, when the polycondensation catalyst solution obtained is less than 0.01% by weight, precipitation tends to occur and clouding tends to occur. Further, water may be added in an appropriate amount to ethylene glycol used at the time of producing the catalyst solution, and may be added during and / or after the production of the catalyst solution.

  The reason why a homogeneous catalyst solution that is stable for a long period of time is obtained in this manner is that a ternary of titanium / alkaline earth metal / phosphorus is obtained by reacting an acidic phosphate ester compound with an alkaline earth metal compound and a titanium compound. This is presumably due to the formation of a complex complex that is stable in a glycol solution.

  The polycondensation catalyst of the present invention contains a ternary complex complex of titanium / alkaline earth metal / phosphorus identified from the results of elemental analysis, infrared spectroscopy (IR) analysis, and anion analysis, preferably And at least one basic structure represented by the following general formula (III).

（式中、Ｔはチタン原子、Ｍはアルカリ土類金属原子、Ｒ^１は炭素数１以上６以下のアルキル基、シクロヘキシル基、アリール基又は２−ヒドロキシエチル基であり、触媒のグリコール溶媒に対する溶解性が優れているエチル基、ブチル基が好ましく、特にエチル基が好ましい。
Ｒ^２は炭素数１〜３のアルキル基であり、触媒のグリコール溶媒に対する溶解性が優れているメチル基が好ましい。）

(In the formula, T is a titanium atom, M is an alkaline earth metal atom, R ¹ is an alkyl group having 1 to 6 carbon atoms, a cyclohexyl group, an aryl group, or a 2-hydroxyethyl group, and is dissolved in a glycol solvent of the catalyst. An ethyl group and a butyl group, which are excellent in properties, are preferable, and an ethyl group is particularly preferable.
R ² is an alkyl group having 1 to 3 carbon atoms, and a methyl group having excellent solubility in a glycol solvent of the catalyst is preferable. )

  The multimeric structure represented by the following general formula (IV) is also a possible form of the ternary complex complex of titanium / alkaline earth metal / phosphorus in the polycondensation catalyst of the present invention.

（式中、Ｔ，Ｍ，Ｒ^１，Ｒ^２は一般式(III)におけると同義である。）

(In the formula, T, M, R ¹ and R ² have the same meanings as in general formula (III).)

<Method for producing polyester resin>
The method for producing the polyester resin of the present invention is not particularly limited except that the polyester polycondensation catalyst of the present invention as described above is used, and basically a conventional method for producing a polyester resin can be used.

  Below, the manufacturing method of the polyester resin of this invention is demonstrated to the example of manufacture of a polyethylene terephthalate as an example of the conventional manufacturing method of a polyester resin.

  As a method for producing polyethylene terephthalate, specifically, a dicarboxylic acid component containing terephthalic acid or an ester-forming derivative thereof as a main component and a diol component containing ethylene glycol as a main component are esterified in an esterification reaction vessel. After reacting or transesterifying in the presence of a transesterification catalyst, the resulting esterification reaction product or the polyester low molecular weight product which is the transesterification reaction product is transferred to a polycondensation tank for polycondensation. Examples of the method include melt polycondensation in the presence of a catalyst, and solid phase polycondensation as necessary. Moreover, this manufacturing method may be a continuous type or a batch type, and is not particularly limited.

  The raw material used is preferably such that the proportion of terephthalic acid or its ester-forming derivative in the dicarboxylic acid component is 90 mol% or more, more preferably 95 mol% or more, and particularly 99 mol% or more, and the diol component It is preferable that the proportion of ethylene glycol in the total be 90 mol% or more, more preferably 95 mol% or more, and particularly preferably 97 mol% or more. When the proportion of terephthalic acid or its ester-forming derivative in the dicarboxylic acid component and the proportion of ethylene glycol in the diol component is less than the above ranges, the mechanical strength, gas barrier property, and heat resistance of the resulting polyester resin as a molded article Tends to decrease.

  Examples of the ester-forming derivative of terephthalic acid include alkyl esters in which each alkyl group has about 1 to 4 carbon atoms, and halides. Examples of dicarboxylic acid components other than terephthalic acid or ester-forming derivatives thereof include, for example, phthalic acid, isophthalic acid, dibromoisophthalic acid, sodium sulfoisophthalic acid, phenylenedioxydicarboxylic acid, 4,4′-diphenyldicarboxylic acid, 4 , 4'-diphenyl ether dicarboxylic acid, 4,4'-diphenyl ketone dicarboxylic acid, 4,4'-diphenoxyethane dicarboxylic acid, 4,4'-diphenylsulfone dicarboxylic acid, 2,6-naphthalenedicarboxylic acid, and other aromatics Cycloaliphatic dicarboxylic acids such as dicarboxylic acid, hexahydroterephthalic acid, hexahydroisophthalic acid, and succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, undecadicarboxylic acid, dodecadicarboxylic acid Aliphatic diacids such as acids Examples include rubonic acid, alkyl esters having about 1 to 4 carbon atoms, halides, etc., and one or more of these dicarboxylic acid components may be used as a copolymer component. Good.

  Examples of the diol component other than ethylene glycol include diethylene glycol, and the proportion of the diethylene glycol in the diol component is preferably 3 mol% or less including the amount of by-product generated in the reaction system. More preferably, it is at least mol% and at most 2.5 mol%. Examples of other diol components include trimethylene glycol, tetramethylene glycol, pentamethylene glycol, hexamethylene glycol, octamethylene glycol, decamethylene glycol, neopentyl glycol, 2-ethyl-2-butyl-1,3- Aliphatic diols such as propanediol, polyethylene glycol, polytetramethylene ether glycol, 1,2-cyclohexanediol, 1,4-cyclohexanediol, 1,1-cyclohexanedimethylol, 1,4-cyclohexanedimethylol, 2,5 -Alicyclic diols such as norbornane dimethylol, and xylylene glycol, 4,4'-dihydroxybiphenyl, 2,2-bis (4'-hydroxyphenyl) propane, 2,2-bis (4 ' aromatic diols such as β-hydroxyethoxyphenyl) propane, bis (4-hydroxyphenyl) sulfone, bis (4-β-hydroxyethoxyphenyl) sulfonic acid, and 2,2-bis (4′-hydroxyphenyl) propane These ethylene oxide adducts or propylene oxide adducts may be used, and one or more of these diolic acid components may be used as a copolymerization component.

  Furthermore, for example, hydroxycarboxylic acids and alkoxycarboxylic acids such as glycolic acid, p-hydroxybenzoic acid, p-β-hydroxyethoxybenzoic acid, and stearyl alcohol, heneicosanol, octacosanol, benzyl alcohol, stearic acid, behenic acid, benzoic acid Monofunctional components such as acid, t-butylbenzoic acid, benzoylbenzoic acid, tricarballylic acid, trimellitic acid, trimesic acid, pyromellitic acid, naphthalenetetracarboxylic acid, gallic acid, trimethylolethane, trimethylolpropane, glycerol, One type or two or more types of trifunctional or higher functional components such as pentaerythritol may be used as a copolymerization component.

  In the present invention, the dicarboxylic acid component containing terephthalic acid or an ester-forming derivative thereof as a main component, the diol component containing ethylene glycol as a main component, and the copolymer component used as necessary are esterified. In the reaction or transesterification reaction, the molar ratio of the diol component to the dicarboxylic acid component is usually 1.02 as a lower limit, preferably 1.03, and usually 2.0 as an upper limit, preferably 1.7. It is common to mix.

  In the case of the transesterification reaction, it is generally necessary to use a transesterification catalyst, and since it is necessary to use a large amount of the catalyst, the polyester production method in the present invention is more effective as a raw material than the transesterification reaction. A method of producing it through an esterification reaction using dicarboxylic acid is preferred.

  For example, the esterification reaction may be performed by using a multistage reaction apparatus in which a single esterification reaction tank or a plurality of esterification reaction tanks are connected in series, and water generated in the reaction and excess ethylene under reflux of ethylene glycol. While the glycol is removed from the system, the esterification rate (the ratio of the esterified by reacting with the diol component out of all the carboxyl groups of the raw dicarboxylic acid component) is usually 90% or more, preferably 93% or more Done. Moreover, it is preferable that the number average molecular weights of the polyester low molecular weight body as an esterification reaction product obtained are 500-5,000.

As an example of reaction conditions in the esterification reaction, when a single esterification reaction vessel is used, the temperature is usually about 200 to 280 ° C., and the relative pressure to atmospheric pressure is usually 0 to 400 kPa (0 to 4 kg / cm ² G). And a reaction time of about 1 to 10 hours with stirring. When a plurality of esterification reactors are used, the lower limit of the reaction temperature in the first stage esterification reactor is usually 240 ° C., preferably 245 ° C., and the upper limit is usually 270 ° C., preferably 265 ° C., reaction pressure. Is a relative pressure to the atmospheric pressure, and the lower limit is usually 5 kPa (0.05 kg / cm ² G), preferably 10 kPa (0.1 kg / cm ² G), and the upper limit is usually 300 kPa (3 kg / cm ² G), preferably 200 kPa ( 2 kg / cm ² G), and the reaction temperature in the final stage is usually 250 ° C., preferably 255 ° C., the upper limit is usually 280 ° C., preferably 275 ° C., and the reaction pressure is usually 0 to 150 kPa relative to atmospheric pressure. (0 to 1.5 kg / cm ² G), preferably 0 to 130 kPa (0 to 1.3 kg / cm ² G) is usually used.

  In the esterification reaction, for example, a tertiary amine such as triethylamine, tri-n-butylamine, benzyldimethylamine, tetraethylammonium hydroxide, tetra-n-butylammonium hydroxide, trimethylbenzyl hydroxide is included in the reaction system. By adding a small amount of quaternary ammonium hydroxide such as ammonium, basic compounds such as lithium carbonate, sodium carbonate, potassium carbonate, sodium acetate, etc., by-production of diethylene glycol from ethylene glycol can be suppressed. .

  As a melt polycondensation method of the low molecular weight polyester thus obtained, a single melt polycondensation tank or a plurality of melt polycondensation tanks connected in series, for example, the first stage is equipped with a stirring blade Using a multi-stage reactor consisting of a fully mixed reactor equipped with a horizontal plug flow reactor equipped with stirring blades in the second and third stages, the produced ethylene glycol was removed from the system under reduced pressure. Generally, a method of performing distillation while distilling is used.

  As an example of the reaction conditions in the melt polycondensation, when a single polycondensation tank is used, the temperature is usually about 250 to 290 ° C., and the pressure is gradually reduced from normal pressure. A method is generally used in which the reaction time is about 0.013 kPa (10 to 0.1 Torr) and the reaction time is about 1 to 20 hours with stirring. In addition, as an example in the case of using a plurality of polycondensation tanks, the reaction temperature in the first stage polycondensation tank is such that the lower limit is usually 250 ° C., preferably 260 ° C., and the upper limit is usually 290 ° C., preferably 280 ° C. The reaction pressure is an absolute pressure, the upper limit is usually 65 kPa (500 Torr), preferably 26 kPa (200 Torr), the lower limit is usually 1.3 kPa (10 Torr), preferably 2 kPa (15 Torr), and the reaction temperature in the final stage is usually lower limit. 265 ° C., preferably 270 ° C., upper limit is usually 300 ° C., preferably 295 ° C., reaction pressure is absolute pressure, upper limit is usually 1.3 kPa (10 Torr), preferably 0.65 kPa (5 Torr), and lower limit is usually 0.00. And a method of 013 kPa (0.1 Torr), preferably 0.065 kPa (0.5 Torr). . Furthermore, as the reaction conditions when using the intermediate stage, intermediate conditions of the above conditions are selected. For example, as an example of the second stage reaction conditions in a three-stage reactor, the reaction temperature is usually 265 ° C. Preferably, 270 ° C., upper limit is usually 295 ° C., preferably 285 ° C., reaction pressure is absolute pressure, upper limit is usually 6.5 kPa (50 Torr), preferably 4 kPa (30 Torr), lower limit is usually 0.13 kPa (1 Torr), Preferably, the method is 0.26 kPa (2 Torr).

  In addition, in the conventional method, the phosphorus compound is usually added at a stage before the start of the polycondensation reaction, but the catalyst of the present invention contains an acidic phosphoric acid ester compound that is a phosphorus compound in advance, so a separate phosphorus compound is added. The polycondensation reaction can also be carried out without this. However, the method of the present invention does not exclude the addition of a phosphorus compound.

  Incidentally, the addition of the polyester polycondensation catalyst of the present invention to the reaction system is carried out at the mixing stage of the dicarboxylic acid component and the diol component, the preparation stage, any stage of the esterification reaction, or the initial stage of melt polycondensation. Either may be sufficient. However, in order to effectively develop the effect of the present invention of producing a polyester resin excellent in color tone and transparency at a high reaction rate, addition of the polyester polycondensation catalyst of the present invention to the reaction system is an esterification reaction. Is preferably carried out after the stage in which the esterification rate becomes 90% or more, after the esterification process is substantially completed, until the initial stage of the melt polycondensation process, particularly before the start of the melt polycondensation. It is more preferable to add to. Especially, it is preferable to add to the esterification reaction product of the last stage esterification reaction tank in a multistage reaction apparatus, or the transfer stage from an esterification tank to a melt polycondensation process. If the polycondensation catalyst is added at a stage where the esterification rate is less than 90%, the polycondensation catalyst may be deactivated by unreacted carboxylic acid, which is not preferable.

  In addition, the number of times of adding the polycondensation catalyst of the present invention is not particularly limited. For example, when used in a batch-type polycondensation reaction, a necessary amount may be added at once, and a plurality of times may be added as necessary. It may be added separately. Similarly, when used in a continuous process, a necessary amount may be added from one place, and may be added separately from a plurality of places as necessary.

  In addition, the polycondensation catalyst of the present invention can be added after being dissolved in the main raw material diol component of the polyester resin to be produced, such as ethylene glycol or 1,4-butanediol. In the polyester polycondensation catalyst of the present invention, the titanium concentration in the obtained polyester resin is usually 0.1 to 200 ppm, preferably 0.5 to 100 ppm, more preferably 3 to 50 ppm, still more preferably 4 in terms of titanium atoms. Used in the range of -20 ppm.

  The intrinsic viscosity ([η1]) of the polyester resin obtained by such melt polycondensation is a value measured at 30 ° C. using a mixed solution of phenol / tetrachloroethane (weight ratio 1/1) as a solvent, and the lower limit is usually 0. .35 dl / g, preferably 0.50 dl / g, and the upper limit is usually 0.75 dl / g, preferably 0.65 dl / g. If the intrinsic viscosity ([η1]) is less than the above range, the operability may be deteriorated when it is extracted from the polycondensation tank described later. On the other hand, if it exceeds the above range, the acetaldehyde content in the resulting polyester resin is reduced. May be difficult.

  Moreover, when using the polyester resin obtained by such melt polycondensation for other uses represented by films and fibers, the lower limit is usually 0 as the value of the intrinsic viscosity ([η1]) measured in the same manner. .50 dl / g, preferably 0.55 dl / g, and the upper limit is usually 0.75 dl / g, preferably 0.70 dl / g. If the intrinsic viscosity ([η1]) is less than the above range, the mechanical strength tends to decrease, and if it exceeds the above range, the moldability may be deteriorated.

  Further, when the polyester resin is used for a hollow molded body, particularly for a bottle, the color tone thereof is 4 or less in color coordinate b value of Hunter's color difference formula by Lab color system described in Reference Example 1 of JIS Z8730. It is preferable that it is 3 or less. When the b value exceeds the above range, the color tone of a molded body such as a bottle tends to be yellowish. On the other hand, in the case where titanium oxide is added as described later for other uses typified by films and fibers, in particular, the b value is 12 or less, particularly 10 or less. It is preferable in terms of the color tone of the fiber. In order to set the color coordinate b value within the above range, a so-called organic toning agent may be added. Examples of the organic toning agent include Solvent Blue 104, Solvent Red 135, and Solvent Violet 36. Pigment Blue 29, 15: 1, 15: 3, Pigment Red 187, 263, Pigment Violet 19, and the like.

  The polyester resin obtained by melt polycondensation as described above is usually extracted in a strand form from an extraction port provided at the bottom of the polycondensation tank, and after being cooled with water or with water, it is cut into pellets by cutting with a cutter. Although it is set as a granular material, such as a chip shape, it is preferable that the granular material after the melt polycondensation is subjected to solid phase polycondensation.

The solid phase polycondensation method can be performed by a conventionally known method, for example, the method described in paragraphs [0057] to [0065] of JP-A-2004-292803.
For example, the resin is usually heated at a temperature of 60 to 180 ° C., preferably 150 to 170 ° C. in an inert gas atmosphere such as nitrogen, carbon dioxide, argon, or the like, or in a steam atmosphere or an inert gas atmosphere containing steam. After crystallizing the surface of the granular material, under an inert gas atmosphere and / or under a reduced pressure of about 1.3 × 10 ^{1 to} 1.3 × 10 ³ Pa in absolute pressure, usually just below the adhesion temperature of the resin It can be subjected to solid phase polycondensation by heat treatment usually at a time of 50 hours or less, at a temperature lower by 80 ° C., preferably at a temperature lower by 10 to 60 ° C. than the adhesion temperature, while allowing the granular materials to flow so that they do not stick together. . By this solid phase polycondensation, the obtained polyester resin can be further increased in polymerization degree, and acetaldehyde, low-molecular oligomers and the like as reaction by-products can be reduced.

  The amount of terminal carboxyl groups of the polyester resin after melt polycondensation subjected to solid phase polycondensation is usually 5 equivalents / ton or more and 50 equivalents / ton or less, preferably 10 equivalents / ton or more and 35 equivalents / ton or less. . When the amount of the terminal carboxyl group exceeds the upper limit, the polycondensation rate at the time of solid phase polycondensation may be decreased, and at the same time, the polyester resin obtained after the solid phase polycondensation is susceptible to hydrolysis, which is not preferable. On the contrary, if the lower limit is not reached, the polycondensation rate during solid phase polycondensation tends to decrease. The amount of the terminal carboxyl group is in a desired range depending on the molar ratio of the dicarboxylic acid component and the diol component at the time of preparing the low molecular weight polyester, the amount of diol used for dissolving the polycondensation catalyst of the present invention, the polycondensation temperature, and the like. It is possible to adjust to.

  The resin obtained by melt polycondensation or solid phase polycondensation as described above may be further processed depending on the purpose such as deactivation of the polycondensation catalyst. For example, water treatment such as immersion in water of 40 ° C. or higher for 10 minutes or more, or water vapor treatment of contacting water vapor of 60 ° C. or higher or water vapor-containing gas for 30 minutes or more can be performed.

  The polycondensation catalyst of the present invention is also suitably used for the production of a polyester resin containing titanium oxide as a pigment especially for fibers. The method has an esterification step and a polycondensation step for polycondensing the reaction product of the esterification step, and the polycondensation step is not particularly limited except using titanium oxide and the polycondensation catalyst. A conventional method for producing a polyester resin can be used, and in the polycondensation step, melt polycondensation and, if necessary, solid phase polycondensation can be carried out subsequently.

  Titanium oxide can be added during the esterification reaction or at any time after the completion of the esterification reaction until the start of the polycondensation reaction.

  Moreover, the addition method of titanium oxide is not particularly limited, and can be performed by a method of adding the powder as it is or a method of adding it as a slurry. However, the addition operation is easy and the addition amount is adjusted accurately. The addition by slurry is preferred. The dispersion medium having titanium oxide as a slurry is not particularly limited, but diols are preferred in that they have little influence on the physical properties of the resulting polyester resin. Among them, ethylene glycol and / or diethylene glycol are preferred, and the strength of the obtained polyester is particularly high. Ethylene glycol is preferred in that it is high.

  Moreover, also when adding a titanium oxide, the adjuvant and stabilizer which prevent deterioration of a polyester resin can be used. Examples of auxiliary agents and stabilizers include phosphate esters such as trimethyl phosphate, triethyl phosphate, tri-n-butyl phosphate, trioctyl phosphate, triphenyl phosphate, tricresyl phosphate, methyl acid phosphate, ethyl acid phosphate, isopropyl Acid phosphates such as acid phosphate, butyl acid phosphate, dibutyl phosphate, monobutyl phosphate and dioctyl phosphate, and phosphorus compounds such as phosphoric acid, phosphorous acid and polyphosphoric acid are preferably used.

  The auxiliary agent and stabilizer are preferably added at the time of preparing the raw slurry, at any stage of the esterification process, or at the beginning of the melt polycondensation process. Auxiliaries and stabilizers are usually used in the range of usually 1 to 1000 ppm as the weight of phosphorus atoms with respect to the total polycondensation raw material, but the range of 3 to 30 ppm is the improvement of color tone, polymerization activity and the heat of the resulting polyester. It is preferable from the viewpoint of improving stability.

  The polyester resin produced by the production method of the present invention can be molded into a hollow molded container such as a bottle by molding it into a preform by, for example, injection molding or extrusion molding, followed by stretch blow molding. The preform made from the polyester resin of the invention has good moldability during stretch blow molding. That is, the preform obtained by molding may be stretch blow molded immediately after molding, or may be blow molded after storing the molded preform for a certain time or unspecified time. At this time, the preform obtained from the normal polyester resin for bottles absorbs moisture as the storage time elapses, and the crystallization speed increases (the temperature rise crystallization temperature Tc1 decreases). During the stretch blow molding, the preform is easily crystallized in the preform heating step, and it becomes difficult to obtain a transparent bottle. However, since the preform using the polyester resin of the present invention has little decrease in Tc1 due to moisture absorption, the preform heating temperature range in which a transparent bottle can be formed even when stretch blow is performed using the preform after storage. Wide and stable stretch blow molding is possible.

  The polyester resin of the present invention produced using the polyester polycondensation catalyst of the present invention is formed into a sheet-like preform by, for example, extrusion molding, and then vacuum molded or compression vacuum molded to form a hollow molded container or dish. In particular, the moldability of the preformed body during vacuum forming or compression vacuum forming is good. Generally, a sheet-shaped preform is stored for a certain time or unspecified time after molding, and then vacuum-formed or compression-molded. Usually, a preform obtained from a polyester resin at this time has a storage time of It absorbs moisture over time and the crystallization speed increases. For this reason, when vacuum forming or compression vacuum forming is performed using a pre-formed body after storage, the pre-formed body is easily crystallized in the heating process of the pre-formed body, making it difficult to obtain a transparent hollow molded container or the like. However, since the preform using the polyester resin of the present invention has little decrease in Tc1 due to moisture absorption, a transparent hollow molded container or the like can be used even when vacuum molding or compression vacuum molding is performed using the preform after storage. The preform can be obtained in a wide range of heating temperatures, and a hollow molded container or the like can be stably molded.

  The polyester resin of the present invention produced using the polyester polycondensation catalyst of the present invention is not limited to such preforms for hollow molded containers and hollow molded containers, but various hollow molded bodies and preforms for hollow molded bodies. It is useful as a raw material for molding of a body, a preform for a hollow molded body, a film, a fiber and the like, and a molded product having excellent quality such as color tone can be obtained.

  EXAMPLES Hereinafter, although an Example and a comparative example are given and this invention is demonstrated further in detail, this invention is not limited by a following example, unless the summary is exceeded.

[Examples and Comparative Examples of Preparation of Polycondensation Catalyst]
Examples and comparative examples for preparing a polycondensation catalyst are given below.
The storage stability evaluation and pH measurement methods for the polycondensation catalysts or polycondensation catalyst solutions prepared in the following Examples and Comparative Examples are as follows.

<Storage Stability Evaluation Method of Polycondensation Catalyst or Polycondensation Catalyst Solution>
As for the polycondensation catalyst, 50 g of special grade ethylene glycol was put into a 50 ml conical flask with a stopper, and the catalyst was added so as to be 0.5% by weight, followed by vigorous stirring with a Teflon stirrer bar for 2 hours. The obtained uniform solution was allowed to stand at room temperature (23 ° C.), and the presence or absence of precipitates after 2 weeks was observed.
Moreover, about the catalyst solution for polycondensation, this was left still at room temperature (23 degreeC), and the mode of the presence or absence of the deposit after 2 weeks was observed.

<Method for Measuring pH of Polycondensation Catalyst or Polycondensation Catalyst Solution>
Using an automatic titrator (AUT-501 type) manufactured by Toa DKK, the measurement was performed by immersing the pH electrode in an ethylene glycol solution or a polycondensation catalyst solution of a polycondensation catalyst in the atmosphere.

The analysis method of the organic component (acetic acid, acetate, butanol, ethanol, ethylene glycol monoacetic acid ester, ethylene glycol) in the polycondensation catalyst or ethylene glycol solution of the catalyst is as follows.
<Analysis of organic components other than carboxylic acid components>
In the case of 50 mg of the polycondensation catalyst or an ethylene glycol solution of the catalyst, 500 mg dissolved or suspended in 10 ml of methanol was used as a sample for gas chromatography measurement. The analysis conditions for gas chromatography are as follows.
Apparatus: HP6890 made by Agilent
Detector conditions: 200 ° C, FID
Column: Agilent HP-INNOWAX 30m × 0.25mmΦ
Film thickness 0.5μm
Carrier: Helium 1ml / min
Temperature rising condition: Hold for 2 min at 40 ° C. after sample injection. Thereafter, the temperature was raised to 60 ° C at 5 ° C / min.
Then, the temperature was raised to 220 ° C. at 10 ° C./min.
Inlet condition: 320 ° C, split ratio 1/50
Sample injection volume: 2 μL
Internal standard substance: Isoamyl alcohol <Analysis of carboxylic acid component>
To about 1500 μl of heavy water, 100 mg of a sample and 5.0 mg of dimethyl sulfoxide (DMSO) as an internal standard substance are added and dissolved. Then, 750 μl of the sample is transferred to a sample tube having an outer diameter of 5 mm, and a Bruker AV400M spectrometer is used. The ¹ H-NMR spectrum was measured at room temperature and with a waiting time of 20 seconds.
This analysis quantified the sum of acetate liganded to metal (CH ₃ COO ⁻ ) and free acetic acid (CH ₃ COOH).
<Elemental analysis (C, H)>
C and H analyzes were performed using a Perkin Elmer 2400II CHN-O elemental analyzer (CHN mode).
<Analysis of metal elements in catalyst>
Plasma emission spectroscopy for 0.1 g of polycondensation catalyst, or 0.2 g of the catalyst in ethylene glycol solution, which was wet-decomposed with hydrogen peroxide in the presence of sulfuric acid in a Kjeldahl flask and then fixed in distilled water. Quantitative analysis was performed using an analyzer (ICP-AES ULTRACE JY-138U type manufactured by JOBIN YVON), and the metal content (% by weight) in the catalyst was converted.
<IR measurement>
Using a Nicolet FT710, 25 mg of a catalyst sample was diluted with 100 mg of diamond powder and then filled in a cell and measured.

(Example 1. Preparation of polycondensation catalyst (polycondensation catalyst A))
139.8 g of magnesium acetate tetrahydrate was placed in a 500 ml glass eggplant-shaped flask equipped with a stirrer, and 250 g of absolute ethanol (purity 99% or more) was further added. Further, 71.6 g of ethyl acid phosphate (mixing weight ratio of monoester and diester was 1: 1.22) was added and stirred at 23 ° C. After confirming that magnesium acetate was completely dissolved after 15 minutes, 75.0 g of tetra-n-butyl titanate was added. Stirring was further continued for 10 minutes to obtain a uniform mixed solution. This mixed solution was transferred to a 1 L eggplant-shaped flask, and concentrated under reduced pressure by an evaporator in an oil bath at 60 ° C. After about 1 hour, most of the ethanol was distilled off, leaving a translucent viscous liquid. The temperature of the oil bath was further increased to 80 ° C., and further concentration was performed under a reduced pressure of 5 Torr. The viscous liquid gradually changed from the surface to a powder form, and was completely pulverized after about 2 hours. Thereafter, the pressure was returned to normal pressure using nitrogen, and the mixture was cooled to room temperature to obtain 183 g of white powder (referred to as polycondensation catalyst A). The obtained catalyst was found to have a weight reduction rate during production of 36% with respect to the total weight of the raw material excluding the ethanol solvent.

Analytical values: Ti 6.0, Mg 8.8, P 9.0, C 26.5, H 6.3 (% by weight)
IR (cm ⁻¹ ): 3500 (νOH), 2980 (νCH), 1400-1600 (νC═O), 1050 (νC—O)
A chart of IR analysis is shown in FIG.

L / M is calculated from the analytical value (molar basis) of the acetate contained in the catalyst and the analytical value of magnesium content (molar basis), and T is calculated from the analytical value of carbon content (weight basis) and titanium content (weight basis). When / C was calculated, the values of L / M (molar ratio) and T / C (weight ratio) were 1.3 and 0.23, respectively.
The storage stability in ethylene glycol was good, and no precipitate was observed. The pH was 6.2.

(Example 2. Preparation of polycondensation catalyst (polycondensation catalyst B))
Synthesis was carried out in the same manner as in Example 1 except that the amount of magnesium acetate tetrahydrate was 116.5 g and the amount of ethyl acid phosphate was 71.4 g, and 171 g of white powder (referred to as polycondensation catalyst B) Got.
Analytical value: Ti6.5, Mg8.1, P9.8, C23.8, H5.1 (wt%)
The L / M and T / C values calculated in the same manner as in Example 1 were 1.0 and 0.27, respectively. Moreover, the storage stability in ethylene glycol was good, and the formation of precipitates was not observed. The pH was 6.1.

(Example 3. Preparation of polycondensation catalyst (polycondensation catalyst C))
Synthesis was carried out in the same manner as in Example 1 except that the amount of magnesium acetate tetrahydrate was 93.1 g and the amount of ethyl acid phosphate was 59.7 g, and 141 g of white powder (referred to as polycondensation catalyst C) was obtained. Obtained.
Analytical value: Ti7.4, Mg7.5, P9.5, C24.6, H5.7 (% by weight)
The values of L / M and T / C calculated in the same manner as in Example 1 were 1.4 and 0.30, respectively. Moreover, the storage stability in ethylene glycol was good, and the formation of precipitates was not observed. The pH was 6.1.

(Example 4. Preparation of polycondensation catalyst (polycondensation catalyst D))
116.6 g of magnesium acetate tetrahydrate was placed in a 500 ml glass-type eggplant type flask equipped with a stirrer, and 250 g of absolute ethanol (purity 99% or more) was further added. Further, 71.6 g of ethyl acid phosphate was added and stirred at room temperature for 20 minutes to obtain a uniform solution. Next, 75.0 g of tetra-n-butyl titanate was added, and this liquid was transferred to a 1 L eggplant-shaped flask, and concentrated with an evaporator at 60 ° C. for about 2 hours to obtain a viscous liquid (polycondensation catalyst D). The solvent was distilled off until 216.5 g remained.
Analytical values: Ti 6.0, Mg 7.5, P 9.0, C 22.2 (% by weight)
Next, 205.5 g of ethylene glycol was added so that the internal volume would be 422 g, and further low-boiling substances were distilled off at 80 ° C. and 5 Torr over 2 hours to obtain a polycondensation catalyst D solution.

In the polycondensation catalyst D, the values of L / M and T / C calculated in the same manner as in Example 1 were 1.6 and 0.27, respectively. The concentration of titanium atoms in the polymerization catalyst solution was 2.5% by weight, and the ratio (weight basis) of titanium atoms, magnesium atoms, and phosphorus atoms was 1: 1.25: 1.5.
The storage stability of this polycondensation catalyst D solution was good, and no precipitate was observed. The pH was 5.8.

(Example 5. Preparation of polycondensation catalyst (polycondensation catalyst E))
23.6 g of magnesium acetate tetrahydrate was placed in a 300 ml glass eggplant-shaped flask equipped with a stirrer, and 126 g of absolute ethanol (purity 99% or more) and 37.5 g of tetra-n-butyl titanate were sequentially added. A homogeneous solution was obtained. Next, 17.2 g of monobutoxyphosphate (BAP) was added, and the mixture was further stirred for 1 hour. After the fine precipitate formed was removed by filtration, the temperature of the oil bath was set to 60 ° C., and the mixture was concentrated with an evaporator over about 2 hours to distill off the ethanol. As a result, a transparent viscous liquid remained. . Further, the temperature of the oil bath was raised to 80 ° C. and the concentration was continued to obtain 53 g of white powder (referred to as polycondensation catalyst E).

Analytical values: Ti 13.0, Mg 6.7, P 7.9, C 29.1, H 5.4 (% by weight)
Composition formula: TiMg (C ₄ H ₉ O ₄ P) (CH ₃ COO) _1.07 (OH) _2.26 (OBu) _0.74
Calculated values: Ti12.6, Mg6.4, P8.2, C28.8, H5.6 (% by weight)
The L / M and T / C values calculated in the same manner as in Example 1 were 1.1 and 0.46, respectively. Moreover, the storage stability in ethylene glycol was good, and the formation of precipitates was not observed. The pH was 6.1.

(Example 6. Preparation of polycondensation catalyst (polycondensation catalyst F))
Synthesis was performed in the same manner as in Example 1 except that the amount of magnesium acetate tetrahydrate was 62.0 g and the amount of ethyl acid phosphate was 35.8 g, to obtain 108 g of pale yellow powder (polycondensation catalyst F). It was.

Analytical values: Ti10.3, Mg6.8, P7.8, C25.1, H5.3 (% by weight)
The L / M and T / C values calculated in the same manner as in Example 1 were 1.0 and 0.41, respectively. Moreover, the storage stability in ethylene glycol was good, and the formation of precipitates was not observed. The pH was 6.1.

(Comparative Example 1. Preparation of polycondensation catalyst (polycondensation catalyst G))
31.8g of magnesium acetate tetrahydrate was put into a 500ml glass eggplant type flask equipped with a stirrer, and 226g of absolute ethanol (purity 99% or more) and tetra-n-butyl titanate were sequentially added. A homogeneous solution was obtained. Next, when 17.2 g of orthophosphoric acid (85 wt% aqueous solution) was added, a large amount of white precipitate was immediately observed. After stirring for 2 hours as it was, the white precipitate precipitated by leaving it to stand for 1 hour was filtered, washed with acetone and diethyl ether, and then air-dried. 50 g of the obtained white solid substance (referred to as polycondensation catalyst G) was pulverized into a powder in an agate mortar.

Analytical value: Ti15.0, Mg7.4, P9.3, C15.9, H4.5 (wt%)
The polycondensation catalyst G was not found to be soluble in ethylene glycol, and the storage stability could not be evaluated.
The values of L / M and T / C calculated in the same manner as in Example 1 were 0.93 and 0.94, respectively.
Thus, it can be seen that when the T / C value exceeds 0.50, solubility in ethylene glycol is lacking, handling is inconvenient, and inconvenient for practical use.

(Comparative Example 2. Preparation of polycondensation catalyst (polycondensation catalyst H))
47.3 g of magnesium acetate tetrahydrate was placed in a 500 ml glass eggplant-shaped flask equipped with a stirrer, and 300 g of ethylene glycol and 75.0 g of tetra-n-butyl titanate were sequentially added. After stirring for 5 hours, a large amount of white precipitate formed was collected by filtration. The obtained white precipitate was washed with acetone and diethyl ether and then dried under reduced pressure to obtain 50 g of a white microcrystalline substance (referred to as polycondensation catalyst H).

As a result of single crystal X-ray structural analysis of this substance, it was found that the ethylene glycol molecule was a metal complex coordinated with titanium and magnesium at a ratio of 2: 1 (molar basis).
Composition formula: TiMg (C ₆ H ₁₂ O ₆ )
Analytical value: Ti19.0, Mg9.5, C28.1, H4.5 (wt%)
The polycondensation catalyst H was not found to be soluble in ethylene glycol, and the storage stability could not be evaluated.
The acetate of the polycondensation catalyst H was below the lower limit of detection, and the L / M and T / C values calculated in the same manner as in Example 1 were 0 and 0.66, respectively.

(Comparative Example 3. Preparation of polycondensation catalyst (polycondensation catalyst I))
500 g of ethylene glycol was put into a 1 L glass eggplant-shaped flask equipped with a stirrer. Further, 23.3 g, 11.9 g and 12.5 g of magnesium acetate tetrahydrate, ethyl acid phosphate, and tetra-n-butyl titanate were added sequentially, and the mixture was stirred and mixed at room temperature for 1 hour. A catalyst solution (referred to as polycondensation catalyst I) having a titanium atom concentration of 0.32% by weight was obtained.

For this catalyst I solution for polycondensation, L / M and T / C were calculated as a mixture of ethyl acid phosphate, magnesium acetate tetrahydrate and tetra-n-butyl titanate as catalyst compositions, and these values were calculated. Are 2.0 and 0.12.
The polycondensation catalyst I solution was allowed to stand at 23 ° C., and the presence or absence of precipitates after 2 weeks was observed, but no precipitates were observed. The pH was 5.5.

  In Table 1, for Examples 1-6 and Comparative Examples 1-3, the catalyst name, catalyst form, titanium, magnesium, carbon, phosphorus atoms, total content of acetic acid and acetate, butanol content (% by weight) in the catalyst, and L / M (molar ratio), T / C (weight ratio), M / P (molar ratio), T / P (molar ratio) and the like calculated from them are summarized. Furthermore, the weight reduction rate during production (a value obtained by dividing the catalyst weight by the total weight of the raw material compound excluding alcohol), the storage stability evaluation result of the catalyst, and the measurement result of the pH, which are also a measure of the catalyst concentration, are shown. It was.

  From Table 1, it can be seen that the polyester polycondensation catalyst of the present invention is excellent in long-term storage stability.

[Examples and comparative examples of polyester resin production]
Examples of polyester resin production and comparative examples are given below.
In addition, the average esterification rate, number average polymerization degree, intrinsic viscosity, solid phase polymerization rate, terminal carboxyl group amount, color tone, diethylene glycol, isophthalic acid unit content, and metal content of the polyester resin in the following Examples and Comparative Examples The amount was determined as follows.

<Average esterification rate>
A solution obtained by dissolving a sample in a mixed solvent of deuterated chloroform / hexafluoroisopropanol (weight ratio 7/3) at a concentration of 3% by weight with a nuclear magnetic resonance apparatus (“JNM-EX270 type” manufactured by JEOL Ltd.) , ¹ H-NMR was measured, each peak was assigned, the amount of terminal carboxyl groups (A mol / ton of sample) was calculated from the integrated value of the peaks, and the ester of all the carboxyl groups of the terephthalic acid unit was calculated by the following formula: The esterification rate (E%) as a proportion of the product that was converted was calculated.
Esterification rate (E) = [1-A / {(1000000 / 192.2) × 2}] × 100

<Number average polymerization degree>
A sample was dissolved in a mixed solvent of deuterated chloroform / hexafluoroisopropanol (weight ratio 7/3) at a concentration of 2% by weight, and a solution obtained by adding 20 μl of pyridine-d ⁵ to a nuclear magnetic resonance apparatus (manufactured by JEOL Ltd., “ JNM-EX270 type "), ¹ H-NMR was measured and each peak was assigned. From the ratio of the integrated value of each peak to the integrated value of the benzene ring proton of the terephthalic acid unit, the terminal hydroxyl group [OH] (mol / Terminal ton), terminal carboxyl group number [COOH] (mole / sample ton), terminal diethylene glycol group number [DEG] (mole / sample ton), and terminal isophthalic acid [IPA] (mole / sample ton) were calculated. The number average degree of polymerization (n) was determined according to the following formula:
Number average degree of polymerization (n)
= 1000000 / {([OH] + [COOH] + [DEG] + [IPA]})
/2/192.2

<Measurement of intrinsic viscosity [η1], [η2]>
In the case of a melt polycondensation resin, 0.25 g of a sample obtained by freeze-pulverizing a polyester resin pellet is used as a solvent with a phenol / tetrachloroethane (weight ratio 1/1) mixture and a concentration (c) of 1.0 g / dl. Was dissolved by holding at 110 ° C. for 30 minutes, and in the case of solid phase polycondensation resin at 120 ° C. for 30 minutes, and then using an Ubbelohde capillary viscosity tube at 30 ° C., the relative viscosity (ηrel) with the stock solution And the ratio (ηsp / c) between the specific viscosity (ηsp) and the concentration (c) determined from the relative viscosity (ηrel) -1 was determined. Similarly, the concentration (c) was 0.5 g / dl, 0. The respective ratios (ηsp / c) were also obtained for 2 g / dl and 0.1 g / dl, and the ratio (ηsp / c) when extrapolating the concentration (c) to 0 was determined from these values. It calculated | required as a viscosity (dl / g).

<Solid-phase polycondensation rate>
The difference ([η2]-[η1]) between the intrinsic viscosity ([η2]) of the solid phase polycondensation resin and the intrinsic viscosity ([η1]) of the melt polycondensation resin is expressed by the solid phase polycondensation time (8 hours). Calculated as the divided value.

<Amount of terminal carboxyl group>
After pulverizing the chip-like polyester resin, it was dried at 140 ° C. for 15 minutes in a hot air dryer, and 0.1 g was accurately weighed from a sample cooled to room temperature in a desiccator, and 3 ml of benzyl alcohol was collected. In addition, it was dissolved at 195 ° C. for 3 minutes while blowing dry nitrogen gas, and then 5 ml of chloroform was gradually added and cooled to room temperature. One to two drops of phenol red indicator were added to this solution, and titrated with a 0.1N sodium hydroxide benzyl alcohol solution with stirring while blowing dry nitrogen gas, and the procedure was terminated when the color changed from yellow to red. Further, as a blank, the same operation was carried out without dissolving the polyester resin sample, and the terminal carboxyl group amount (acid value) was calculated by the following formula <1>.
Terminal carboxyl amount (equivalent / ton) = (ab) × 0.1 × f / w <1>
(Where a is the amount of 0.1N sodium hydroxide in benzyl alcohol solution required for titration (μl), b is the amount of 0.1N sodium hydroxide in benzyl alcohol solution required for titration with a blank. The amount (μl), w is the amount of the polyester resin sample (g), and f is the titer of 0.1N sodium hydroxide in benzyl alcohol.)

In addition, the titer (f) of the benzyl alcohol solution of 0.1N sodium hydroxide was calculated | required with the following method. Collect 5 ml of methanol in a test tube, add 1-2 drops as an indicator of an ethanol solution of phenol red, Titrate with 0.4 ml of 1N sodium hydroxide in benzyl alcohol to the color change point, then add 0.2 ml of 0.1N aqueous hydrochloric acid solution with known titer as a standard solution, and add 0.1N hydroxide again. The solution was titrated with a sodium benzyl alcohol solution to the discoloration point (the above operation was performed under dry nitrogen gas blowing). The titer (f) was calculated by the following formula <2>.
Titer (f) = Titer of 0.1N hydrochloric acid aqueous solution x Sampling amount of 0.1N hydrochloric acid aqueous solution (μl) /
Titration volume of 0.1N sodium hydroxide in benzyl alcohol (μl) <2>

<Color tone>
A chip-shaped polyester resin obtained by polycondensation reaction is filled into a cylindrical powder measuring cell having an inner diameter of 30 mm and a depth of 12 mm, and a colorimetric color difference meter ZE-2000 (Nippon Denshoku Industries Co., Ltd.) is used. The color b value based on the color coordinate of Hunter's color difference formula in the Lab display system described in Reference Example 1 of JIS Z8730 is a value obtained by rotating the measurement cell 90 degrees by the reflection method and measuring four points. It calculated | required as a simple average value.

<Content of diethylene glycol (DEG) and isophthalic acid (IPA) units>
A polyester chip was dissolved in deuterated trifluoroacetic acid at room temperature to obtain a 3 wt% solution. ¹ H-NMR was measured using a JNM-EX270 type nuclear magnetic resonance apparatus manufactured by Nippon Denshoku Co., Ltd., and each peak was assigned. The amount of diethylene glycol in the polyester resin (mol%) and isophthalate were determined from the integration ratio. The acid amount (mol%) was calculated.

(Example 7)
<Esterification reaction>
A continuous polymerization apparatus comprising a slurry preparation tank, a two-stage esterification reaction tank connected in series to the slurry preparation tank, and a three-stage melt polycondensation tank connected in series to the second-stage esterification reaction tank was used. High-purity terephthalic acid, isophthalic acid and ethylene glycol are continuously fed into the slurry preparation tank at 90.85 parts by weight, 2.45 parts by weight and 57.50 parts by weight, respectively, and the slurry is stirred and mixed. Prepared. This slurry was subjected to a first-stage esterification reaction tank set at 260 ° C. in a nitrogen atmosphere, a relative pressure of 100 kPa (1.0 kg / cm ² G), and an average residence time of 4 hours, and 260 ° C. in a nitrogen atmosphere. The relative pressure was 5 kPa (0.05 kg / cm ² G), and the average residence time was sequentially supplied to the second stage esterification reaction tank set to 1.5 hours. In this second-stage ester reaction tank, the polycondensation catalyst A prepared in Example 1 is obtained as an ethylene glycol solution having a titanium metal concentration of 844 ppm and a water concentration of 0.5% by weight through the upper pipe. 0.945 parts by weight per hour was added so that the titanium concentration was 8 ppm with respect to the polyester resin. The average esterification rate in each esterification reaction tank is 89 ± 1% in the first stage and 96 ± 1% in the second stage, and the number average degree of polymerization is 6.5 in the second stage. Met.
In addition, diethylene glycol was fed to the second stage esterification reaction tank so that the number of moles of diethylene glycol in the obtained polyester resin was 3.0 mol%.

<Melt polycondensation reaction>
Subsequently, the esterification reaction product obtained above was continuously transferred to a melt polycondensation tank, and the first stage was set at 270 ° C., absolute pressure 2.6 kPa (20 Torr), and residence time 1.2 hours. Second melt polycondensation tank, then 278 ° C., second pressure melt polycondensation tank set to absolute pressure 0.33 kPa (2.5 Torr), residence time 1.0 hour, then 280 ° C., residence time The polyester resin obtained is continuously transferred to the third stage melt polycondensation tank set for 1.0 hour so that the intrinsic viscosity ([η1]) of the obtained polyester resin is 0.65 ± 0.01 dl / g. The pressure in the third stage melt polycondensation tank is adjusted and melt polycondensed, and continuously extracted in a strand form from the outlet provided at the bottom of the melt polycondensation tank, water cooled and cut with a cutter. A polyester resin in the form of a chip was produced.
30 grains were arbitrarily extracted from the obtained chip-like polyester resin, and the weight of each was measured. The average value per piece was 17 mg.

<Solid-phase polycondensation reaction>
Subsequently, the chip-like polyester resin obtained by melt polycondensation was continuously supplied into a stirring crystallizer maintained at 160 ° C. so as to have a residence time of 5 minutes for crystallization. The crystallized resin was further dried in an IPHH-201 type inert oven manufactured by ESPEC under a nitrogen stream of 40 L / min (oxygen concentration 2 ppm) at 160 ° C. for 2 hours, and then heated at 210 ° C. for 8 hours to solidify. Phase polycondensation was performed.

(Example 8)
A polycondensation reaction was carried out in the same manner as in Example 7 except that the polycondensation catalyst B prepared in Example 2 was used instead of the polycondensation catalyst A prepared in Example 1.

Example 9
A polycondensation reaction was carried out in the same manner as in Example 7 except that the polycondensation catalyst C prepared in Example 3 was used instead of the polycondensation catalyst A prepared in Example 1.

(Example 10)
In place of the polycondensation catalyst A prepared in Example 1, the polycondensation catalyst C prepared in Example 3 was used so that the amount used was 4 ppm in terms of titanium atom in the polyester resin obtained, and the place of addition The polycondensation reaction was carried out in the same manner as in Example 7 except that the esterification reaction product was continuously added as a pipe for transferring the esterification reaction product to the melt polycondensation tank.

(Example 11)
Implemented except that the catalyst solution of the polycondensation catalyst D prepared in Example 5 was further diluted with ethylene glycol to 844 ppm titanium atoms in place of the polycondensation catalyst A prepared in Example 1. A polycondensation reaction was carried out in the same manner as in Example 7.

(Example 12)
A polycondensation reaction was carried out in the same manner as in Example 7 except that the polycondensation catalyst E prepared in Example 6 was used instead of the polycondensation catalyst A prepared in Example 1.

(Example 13)
A polycondensation reaction was carried out in the same manner as in Example 7 except that the polycondensation catalyst F prepared in Example 7 was used instead of the polycondensation catalyst A prepared in Example 1.

(Comparative Example 4)
When the polycondensation reaction was carried out in the same manner as in Example 7 except that the polycondensation catalyst G prepared in Comparative Example 1 was used instead of the polycondensation catalyst A prepared in Example 1, the third-stage melting was performed. Even in the operation at the upper limit of the vacuum degree of the polycondensation tank, the polymerization did not increase to the target viscosity, and the polymerization could not be continued.

(Comparative Example 5)
Instead of the polycondensation catalyst A prepared in Example 1, 2.3 parts by weight of the polycondensation catalyst H prepared in Comparative Example 2 was added to 500 parts by weight of ethylene glycol to obtain 840 ppm as titanium atoms, A polycondensation reaction was carried out in the same manner as in Example 7 except that 1.4 parts by weight of ethyl acid phosphate was added and mixed, and a slurry-like catalyst solution having 633 ppm as a phosphorus atom was used. Even in the operation at the upper limit of the vacuum degree of the condensation tank, the polymerization did not increase to the target viscosity, and the polymerization could not be continued.

(Comparative Example 6)
A polycondensation reaction was carried out in the same manner as in Example 7 except that the polycondensation catalyst I solution prepared in Comparative Example 3 was used instead of the polycondensation catalyst A prepared in Example 1. Even in the operation at the upper limit of the vacuum degree of the melt polycondensation tank, the polymerization did not increase to the target viscosity, and the polymerization could not be continued.

  Table 2 summarizes the production conditions, physical properties of the melt polycondensation product and the solid phase polycondensation product, and the like for Examples 8 to 13 and Comparative Examples 4 to 6.

(Example 14)
A reaction vessel equipped with a stirrer, a distillation tube, and a decompressor was charged with 112.9 g of terephthalic acid and 183.1 g of 1,4-butanediol. To this was added a solution in which the catalyst F obtained in Example 6 was dissolved in 1,4-butanediol to make the titanium atom 4.5 wt%. The amount added was 40 ppm as titanium atoms per polybutylene terephthalate obtained.
After the inside of the reaction vessel was purged with nitrogen, the reaction vessel was heated in a 150 ° C. oil bath. While stirring the reaction solution, the internal pressure of the can was maintained at 79 kPa, the internal temperature of the reaction can was raised to 220 ° C. over 60 minutes, and the esterification reaction was carried out while distilling off the water generated by holding at 220 ° C. for 170 minutes. went. After completion of the esterification reaction, the temperature was raised to 245 ° C. over 60 minutes and maintained at 245 ° C. On the other hand, the pressure was reduced from 79 kPa to 0.13 kPa over 85 minutes, and the polycondensation reaction was performed. The polycondensation reaction time (the time from 79 kPa when the pressure reduction start time was 0 hour and the reaction was completed) was 170 minutes, the intrinsic viscosity was 0.909 dL / g, and the color tones L, a, and b were 84.1, A -1.5 polybutylene terephthalate was obtained.

  From the results of Table 2 and Example 14, it can be seen that the polyester resin obtained using the polyester polycondensation catalyst of the present invention has particularly good color tone.

[Examples of polyester resin bottle molding and comparative examples]
Examples of polyester resin bottle molding and comparative examples are given below.
In the following, the preform crystallization temperature Tc1, the water content, the surface temperature, and the haze of the molded bottle were measured as follows.

<Crystallization temperature Tc1>
It means the crystallization peak temperature at the time of temperature rise measured by a differential scanning calorimeter (DSC) in accordance with JISK7121, and a sharp knife such as a cutter is used to remove about 10 milligrams of sample from the top surface of the plug portion of the preform. It is the temperature value of the exothermic peak that appears first, measured at a temperature rising rate of 20 ° C./min with a DSC220C model, Senko Instruments.

<Moisture content>
About 1 gram of a sample was cut out from the stopper portion of the preform subjected to the moisture absorption treatment with a nipper or the like, and used as a sample for moisture measurement. The moisture content was measured using a Karl Fischer moisture meter CA-06, VA-06 manufactured by Mitsubishi Chemical Corporation, using Aquamicron AX as the anolyte and Aquamicron CKS as the catholyte, heating temperature 230 ° C., heating time 30 minutes, The measurement was performed under the condition of a nitrogen flow rate of about 200 ml / min.

<Surface temperature of preform>
Using a non-contact handy thermometer IT2-80 manufactured by Keyence Corporation with an emissivity set to 0.90, the surface temperature after the heat treatment was measured from a distance of about 0.3 m.

<Haze>
The trunk of the obtained polyester resin container was cut out, and the haze was measured with a haze meter (SM color computer MODEL SM-5, manufactured by Suga Test Instruments Co., Ltd.).

(Example 15)
About 5 kilograms of the solid phase polycondensed polyester resin chip (using the polycondensation catalyst E) obtained in Example 12 was flattened on a stainless steel bat having a length × width × height of approximately 300 × 500 × 80 mm. Then, using a vacuum dryer DP63 manufactured by Yamato Scientific Co., Ltd., vacuum drying was performed at 145 ° C. for about 12 hours. For the purpose of preventing moisture absorption during molding, the raw material resin after the vacuum drying was put into a Challenger D-50 resin dryer manufactured by Kawata Co., Ltd., and a preform was injection molded while being held at 135 ° C.

  Injection molding uses a multi-layer stretch blow machine injection molding machine (manufactured by Nissei ASB Co., model: ASB-50TH), the cylinder set temperature and the hot runner set temperature are set to 270 ° C., and the injection is 1.5 seconds. A preform (internal capacity 30 ml) having a length of 100 mm, an outer diameter of 25 mm, and a wall thickness of 4 mm having a cap portion was prepared under the conditions of pressure holding of 13.5 seconds, cooling of 10 seconds, and a mold temperature of 15 ° C.

  The obtained preform was put into a constant temperature and humidity chamber (manufactured by Tabay Espec, platinum rainbow PR-1GP type) set at 40 ° C. and a relative humidity of 90% to perform moisture absorption treatment. Preforms with different moisture contents were obtained by changing the treatment time.

The obtained preform was subjected to stretch blow molding by adjusting the heating time of the preform by the method shown below, and the haze of the stretch blow bottle obtained was measured.
In other words, the preform moves 90 degrees each in the order of the preform input and bottle take-out part, the primary heating part equipped with the near infrared heater, the secondary heating part, and the blow molding part, and the rotary type that forms the stretch blow bottle Using a stretch blow molding machine, the primary heating time of the preform is from 40 seconds to 62.5 seconds, the secondary heating time is from 15 seconds to 37.5 seconds, and the cooling time after the completion of the secondary heating in the secondary heating section is A polyester resin container having a length of about 200 mm, an outer diameter of about 60 mm, an average wall thickness of about 0.5 mm, and an internal volume of 500 ml was formed by setting a setting of 25 seconds and injecting compressed air of about 3 MPa.

Measure the moisture content of the preform and the crystallization temperature Tc1 and the haze of the molded bottle,
Table 3 shows the results of the preform surface temperature at which the haze is 1% or less as the preform surface temperature at which a good bottle can be formed.

(Comparative Example 7)
Preform injection molding and moisture measurement in the same manner as in Example 16 except that Unipet BK2180 manufactured by Nihon Unipet Co. was used instead of the polyester resin chip obtained by solid phase polycondensation obtained in Example 12. Then, crystallization temperature Tc1 measurement, blow molding of stretched bottles, and haze measurement were carried out, and the surface temperature of the preform that was able to form a good bottle was similarly examined. The results are shown in Table 4.

  From the comparison of Table 3 and Table 4, the preform obtained from the polyester resin of the present invention has little change in the crystallization temperature Tc1 even when it absorbs moisture, and the surface temperature range of the preform from which a transparent bottle can be obtained is wide. It can be seen that stable production is possible.

[Examples of polyester resin production using titanium oxide and comparative examples]
Examples of polyester resin production using titanium oxide and comparative examples are given below.
(Example 16)
Using terephthalic acid and ethylene glycol as raw materials, 157 g of an ethylene terephthalate low polymer produced by a direct esterification method was dissolved at 260 ° C. The esterification rate of this low polymer was 96.5%. Thereafter, it was added as a slurry of 34% by weight of ethylene glycol so as to be 0.35% by weight with respect to the theoretical yield of the polyester resin from which titanium oxide was obtained, and the polycondensation catalyst prepared in Example 4 was obtained. It added so that it might become 20 ppm as a titanium atom with respect to the theoretical yield of the polyester resin obtained.
Next, while stirring the solution with a stirring blade, the temperature is raised stepwise to 280 ° C. over 80 minutes, and the pressure of the reaction system is lowered stepwise from normal pressure to absolute pressure 1.3 × 10 ² Pa over 60 minutes. After reaching a temperature of 280 ° C. and an absolute pressure of 1.3 × 10 ² Pa, the temperature and pressure were kept constant.
After 270 minutes from the start of decompression, stirring was stopped, and nitrogen gas was introduced into the system to complete the polycondensation reaction. Thereafter, the polymer was extracted from the reaction vessel and cooled with water to obtain a strand polymer. This was cut into pellets and evaluated.
Table 5 shows the measurement results of the time from the start of decompression to the termination of the polycondensation reaction (polycondensation reaction time), the intrinsic viscosity of the obtained polyester resin, and the color coordinate b as the color tone.

(Example 17)
A polycondensation reaction and evaluation were carried out in the same manner as in Example 16 except that the polycondensation catalyst prepared in Example 2 was added so as to be 15 ppm as a titanium atom with respect to the theoretical yield of the obtained polyester resin. The results are shown in Table 5.

(Comparative Example 8)
<Preparation of catalyst for polycondensation>
A tetrabutoxy titanium solution was prepared by the following method.
Under a nitrogen atmosphere, 100 ml of ethylene glycol was weighed into a 200 ml flask, and 0.7 g of tetrabutoxy titanium was added dropwise while stirring the flask. After completion of the dropwise addition, the mixture was stirred at room temperature for 1 hour to obtain a colorless and transparent solution.
Separately, a magnesium acetate solution was prepared by the following method.
200 ml of ethylene glycol was weighed into a 500 ml flask, and 2.2 g of magnesium acetate tetrahydrate was added while stirring the flask. After completion of the addition, the mixture was stirred at room temperature for 30 minutes to obtain a colorless and transparent solution.
<Melting polycondensation>
In Example 16, instead of introducing the polycondensation catalyst into the reactor, the ethylene glycol solution of tetrabutoxytitanium prepared above was used in an amount of 6 ppm as a titanium atom with respect to the theoretical yield of the obtained polyester resin. Separately, 8 ppm as the magnesium atom relative to the theoretical yield of the polyester resin from which the hydrated ethylene glycol solution can be obtained, and 10 ppm relative to the theoretical yield of the polyester resin from which the ethylene glycol solution of ethyl acid phosphate can be obtained. The polycondensation reaction and the evaluation were carried out in the same manner as in Example 16 except for the addition. The results are shown in Table 5.

  It can be seen from Table 5 that even in the production of a polyester resin using titanium oxide, a polyester resin having a good color tone can be obtained according to the present invention.

[Examples of polycondensation catalyst solution and polyester resin production]
(Example 18. Preparation of polycondensation catalyst solution (polycondensation catalyst J solution))
Put 60.72 g of magnesium acetate tetrahydrate in a 1 L Erlenmeyer flask with a stopper, add 360 g of absolute ethanol and stir for 30 minutes, then add 96.26 g of tetrabutyl titanate and stir for 20 minutes to obtain a homogeneous solution Got. Next, with vigorous stirring, monoethyl acid phosphate (JAMP-2 manufactured by Johoku Chemical Industry Co., Ltd., purity 72.6% by weight, diethyl acid phosphate 14.5% by weight, and orthophosphoric acid 13.0% by weight are contained. ) Was added over 30 minutes to obtain a slightly cloudy solution.

This solution was transferred to a 1 L eggplant flask, and ethanol was distilled off under reduced pressure at an oil bath temperature of 80 ° C. until the content was 322.2 g.
Next, 389.25 g of ethylene glycol was added under normal pressure of nitrogen and mixed for 15 minutes to prepare a uniform solution.
Next, the low boiling point substance was removed by treating under reduced pressure of 10 Torr (1.3 × 10 ⁻³ MPa) for 40 minutes to obtain 508.0 g of a pale yellow polycondensation catalyst J solution. The pH of this solution was 5.4, and it was stable as a uniform solution.

(Example 19. Preparation of polycondensation catalyst solution (polycondensation catalyst K solution))
48.5 g of magnesium acetate tetrahydrate was put into a 1 L Erlenmeyer flask with a stopper. In addition, 140 g of ethanol was added. Next, 31.7 g of ethyl acid phosphate (Johoku Chemical Co., Ltd., JP-502) was added and stirred for 20 minutes to obtain a homogeneous solution, and 38.5 g of tetrabutyl titanate was added with stirring over 15 minutes. It was. This was transferred to a 1 L eggplant flask and concentrated on an oil bath at 60 ° C. using an evaporator. The recovered distillate amount was 124.6 g.
Next, after restoring pressure with nitrogen, 81.3 g of ethylene glycol was added under normal pressure, and the mixture was stirred at room temperature for 20 minutes. The liquid was further evaporated with an evaporator at 60 ° C. and 5 Torr (0.67 × 10 ⁻³ MPa) over about 1 hour to obtain 157.7 g of a pale yellow polycondensation catalyst K solution. The pH of the solution was 5.4, and it was stable as a homogeneous solution.

  In Table 6, for Examples 18 and 19, the catalyst name, catalyst form, titanium, magnesium, carbon, phosphorus atom, total content of acetic acid and acetate, butanol content (% by weight) in the catalyst, and calculated from them L / M (molar ratio), T / C (weight ratio), M / P (molar ratio), T / P (molar ratio), etc. were summarized. Furthermore, the weight reduction rate during production (a value obtained by dividing the catalyst weight by the total weight of the raw material compound excluding alcohol), the storage stability evaluation result of the catalyst, and the measurement result of the pH, which are also a measure of the catalyst concentration, are shown. It was.

(Example 20)
Instead of the polycondensation catalyst A prepared in Example 1, the polycondensation catalyst J solution prepared in Example 18 was used, and the esterification reaction product was continuously transferred to the melt polycondensation tank at the addition site. A polycondensation reaction was carried out in the same manner as in Example 7 except that the temperature in the first, second, and third stage polymerization tanks was changed to 266 ° C., 283 ° C., and 290 ° C., respectively.

(Example 21)
The polycondensation catalyst K solution prepared in Example 19 was used in place of the polycondensation catalyst A prepared in Example 1, and the temperatures of the first, second, and third stage polymerization tanks were each 266 ° C. The polycondensation reaction was carried out in the same manner as in Example 7 except that the temperature was changed to 283 ° C. and 290 ° C.

  Table 2 above summarizes the production conditions, physical properties of the melt polycondensation product and the solid phase polycondensation product, and the like for Examples 20 and 21.

2 is an IR analysis chart of the polycondensation catalyst produced in Example 1. FIG.

Claims (12)

A catalyst for polyester polymerization containing a titanium atom, an alkaline earth metal atom, a phosphorus atom and a carbon atom,
At least some of the carbon atoms are derived from organic acids and / or carboxylates;
The content T (weight basis) of titanium atoms is 4 to 20% by weight,
Organic acid and / or carboxylate content L (molar basis), alkaline earth metal atom content M (molar basis), titanium atom content T (weight basis), phosphorus atom content P (molar basis) ), And a carbon atom content C (by weight) satisfying the following formulas (1), (2), and (3).
0.8 ≦ L / M (molar ratio) ≦ 1.8 (1)
0.05 ≦ T / C (weight ratio) ≦ 0.50 (2)
0.5 ≦ M / P (molar ratio) ≦ 3.0 (3)   The polyester polycondensation catalyst according to claim 1, obtained by mixing an alcohol, a titanium compound, an alkaline earth metal compound, and an acidic phosphate compound and concentrating the mixture. The ratio W ₁ / W ₀ between the weight W _{1 of the} obtained polyester polycondensation catalyst and the sum W ₀ of the weights of the titanium compound, alkaline earth metal compound, and acidic phosphate compound used for mixing was 0 The catalyst for polyester polycondensation according to claim 2, which is from .45 to 0.85.   The polyester polycondensation catalyst according to claim 2 or 3, wherein the alkaline earth metal compound is an organic acid salt of alkaline earth metal and / or a hydrate thereof. The polyester polycondensation catalyst according to any one of claims 1 to 4, comprising a basic structure represented by the following general formula (III).

Wherein T is a titanium atom, M is an alkaline earth metal atom, O is an oxygen atom, P is a phosphorus atom, R ¹ is an alkyl group having 1 to 6 carbon atoms, a cyclohexyl group, an aryl group, or 2-hydroxyethyl And R ² is an alkyl group having 1 to 3 carbon atoms.)   The polyester polycondensation catalyst according to any one of claims 1 to 5, which is a solid.   A liquid polyester polycondensation catalyst solution comprising the polyester polycondensation catalyst according to any one of claims 1 to 6 and ethylene glycol and / or 1,4-butanediol.   The polyester polycondensation catalyst according to any one of claims 1 to 6, water, ethylene glycol and / or 1,4-butanediol, wherein the water content is 0.01 to 10% by weight. The polyester polycondensation catalyst solution according to claim 7, wherein the titanium atom content (by weight) is 300 to 100,000 ppm and is liquid.   After mixing ethylene glycol and / or 1,4-butanediol with a liquid substance obtained by mixing alcohol, titanium compound, alkaline earth metal compound, and acidic phosphate compound, and concentrating the mixture, Furthermore, the catalyst solution for polyester polycondensation of Claim 7 or 8 obtained through the process of distilling a substance with a boiling point lower than ethylene glycol and / or 1,4-butanediol.   A method for producing a polyester resin using the polyester polycondensation catalyst according to any one of claims 1 to 6 and / or the polyester polycondensation catalyst solution according to any one of claims 7 to 9.   The polyester resin obtained by the manufacturing method of the polyester resin of Claim 10. Ru obtained from the polyester resin of claim 11, hollow moldings, films, fibers or hollow molded body preform.

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