JP2958588B2 - Polyester production method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a polyester suitable for forming a photographic support.

[0002]

2. Description of the Related Art Polyesters represented by polyethylene terephthalate have excellent mechanical strength and chemical stability.
In addition to fiber, film uses such as photography, magnetic tape,
Widely used for packaging, condensers, etc. As a method for producing polyethylene terephthalate, a DMT method using dimethyl terephthalate and ethylene glycol as raw materials and a direct polymerization method using terephthalic acid and ethylene glycol as raw materials (hereinafter abbreviated as a direct polymerization method) are well known. There are a batch production method and a continuous production method. Conventionally, polyester films have often been manufactured by the DMT method, but in recent years, each manufacturer has been switching to the direct-weight method in order to reduce manufacturing costs.

[0003] Polyester film is usually obtained by melt-extruding with an extruder and then uniaxially or biaxially stretched.
The adhesion between the cooling drum and the unsolidified sheet polyester during melt extrusion is a very important factor in determining the flatness of the film surface, and in order to improve this, the extruder die and the cooling drum must be connected. An electrode for applying a high voltage is provided between the electrodes to generate electric charge in the unsolidified polyester, thereby improving the adhesion to the cooling drum (hereinafter referred to as electrostatic application characteristics).
(For example, Japanese Patent Publication No. 37-6142). However, if the film forming speed is increased to increase the productivity of the film, the amount of electric charge deposited on the unsolidified sheet is reduced, and the adhesion to the cooling drum is deteriorated. Unevenness is created. A film obtained by stretching such a sheet has poor surface flatness, and cannot be used especially for photographic use. This phenomenon is particularly conspicuous in the polyester of the direct weight method in which a metal catalyst is not used in the esterification reaction, as compared with the polyester of the DMT method in which a large amount of a metal compound is used as a catalyst for the transesterification reaction.

Attempts have been made to improve the amount of charge deposition by adding an alkali metal compound or an alkaline earth metal compound to the polyester production process (for example, Japanese Patent Application Laid-Open No.
1-70269). However, adding a large amount of such metals to the polyester easily generates fine aggregated foreign substances and by-produces an ether bond that lowers the softening point of the polymer, and tends to cause coloring of the polymer, and is obtained by this method. It is difficult to use polyester as a raw material for a polyester film having a quality that can be practically used as a photographic support.

As means for solving such a problem, a technique of adding an alkali metal and / or alkaline earth metal compound compound and a phosphorus compound in addition to a metal compound such as magnesium, manganese or zinc (for example, JP-A-55-84322, JP-A-55-89329
And a technique of adding a tertiary amine or quaternary ammonium hydroxide and a phosphorus compound in addition to a compound of a metal such as magnesium or manganese (for example, JP-A-55-115).
No. 425) is also disclosed.

In order to improve the electrostatic application characteristics during film formation, a compound selected from a glycol-soluble magnesium compound, a glycol-soluble manganese compound or a glycol-soluble zinc compound and a specific nitrogen-containing basic compound are used in the polymerization step. It is known to add. (For example,
JP-A-1-266129, JP-A-1-26613
No. 0, JP-A-1-287133) As a polymerization catalyst, an antimony compound or a germanium compound is usually used. Antimony compounds are often used because they are inexpensive, but the catalyst is reduced in the polymerization process and precipitates in the polymer as antimony metal. In particular, in the presence of the above-mentioned additives, antimony is easily reduced, and this is present as a large amount of foreign substances in the polymer. When a photographic support obtained from such a polyester is used for a high-resolution lithographic film, foreign matters cause image defects, and it has been difficult to satisfy the required quality of products.

[0007]

SUMMARY OF THE INVENTION An object of the present invention is to provide a polyester suitable for producing a photographic film support, which is excellent in electrostatic application characteristics at the time of film formation, has little foreign matter, and has good transparency. It is to provide a method of manufacturing the.

[0008]

The above objects can be attained by the following method for producing a polyester. That is, 1) one or two or more compounds selected from a glycol-soluble magnesium compound, a glycol-soluble manganese compound, and a glycol-soluble zinc compound mainly containing an aromatic dicarboxylic acid mainly containing terephthalic acid and a glycol mainly containing ethylene glycol. When producing a polyester by coexisting a nitrogen-containing basic compound and a phosphorus compound, a glycol solution in which a glycol-soluble germanium compound is completely dissolved as a polymerization catalyst is added so as to satisfy the following formula. Is a method for producing a polyester.

1.0 <M <8.0 (1) 0.03 <M / P <0.30 (2) 0.02 <A / (M + G) <0.30 (3) 0.27 <G <2.75 (4) M: Addition amount of magnesium, manganese and zinc atoms to polymer [g atom / t] P: Addition ratio of phosphorus atom to polymer [PPM] A: Addition mole of nitrogen-containing basic compound to polymer Number [mol / t] G: Amount of germanium atom added to polymer [g atom / t]

Also, 2) the germanium compound is ethylene
0.2 wt% as germanium atom to glycol
165 ° C or more and 195 ° C or less at a concentration of not less than 0.7 wt%
At the temperature below, ethylene glycol completely dissolved within 8 hours
Characterized in that a recall solution is used as a catalyst solution.
The method for producing a polyester according to the above 1). Further, 3) the ethylene glycol solution of the completely dissolved germanium compound is reacted with an aromatic dicarboxylic acid mainly composed of terephthalic acid and a glycol mainly composed of ethylene glycol substantially before the esterification reaction is started. The method for producing a polyester according to the above 1), wherein the polyester is added to the polyester.

If the amount of the glycol-soluble metal atom and the amount of the phosphorus compound deviate from the above formulas (1) and (2), FIG.
As shown in the figure, the electrostatic application characteristics during film formation cannot be maintained, and only a base having poor flatness can be obtained, or the polymer is colored, and only an unfavorable polyester can be obtained as a photographic support raw material. . If the amount of the nitrogen-containing basic compound is small relative to the total amount of the glycol-soluble metal atoms and the germanium atoms, by-products of diethine glycol, which lowers the softening point of the polymer, increase. Further, if the content of the nitrogen-containing basic compound is large, the polymer is colored and any of them is not preferable as a raw material for a photographic support.

If the amount of germanium atoms is less than 0.27 g atom / t (per ton of polymer), the progress of polymerization is slow, and not only does the productivity of the polymer decrease,
Since the polymer is exposed to high heat for a long time, an undesirable decomposition reaction occurs and the quality of the polymer is reduced. Further, if the amount of germanium atoms is more than 2.75 g atom / t, the effect of accelerating polymerization in proportion to the amount is small, and the cost is increased, which is not preferable. Adding an ethylene glycol solution of a germanium compound to the reaction system before starting the esterification reaction enhances the dispersion effect of the germanium compound and has an effect of further suppressing the generation of foreign matter in the polyester. .

Further, if it takes a long time to dissolve the germanium compound in glycol, not only does the productivity decrease, but also the amount of diethylene glycol in ethylene glycol increases, leading to a deterioration in polymer quality. If the dissolution is discontinued in the middle and added to the reaction system without dissolution, the amount of foreign substances in the polymer increases, and the material for the photographic support which is the object of the present invention lacks suitability.

Examples of the germanium compound soluble in glycol include germanium dioxide and germanium tetrachloride. Germanium dioxide is preferred.
At a temperature of 65 ° C. or more and 195 ° C. or less, 0.2 wt% or more and 0.7 wt% or more of germanium atoms with respect to ethylene glycol.
Preference is given to hexagonal or amorphous forms, or mixtures thereof, which dissolve within 8 hours at concentrations of less than wt%.

The present invention is also applicable to polyesters containing the following copolymer components other than polyethylene terephthalate. Examples of the copolymerization component include aromatic dicarboxylic acids such as isophthalic acid, alicyclic dicarboxylic acids such as cyclohexanedicarboxylic acid, and aliphatic dicarboxylic acids such as adipic acid and sebacic acid as dicarboxylic acid components. Examples of the glycol component include, in addition to ethylene glycol, propylene glycol, butylene glycol, diethylene glycol, and triethylene glycol. Further, the glycol containing ethylene glycol as a main component used for heating and dissolving and diluting the germanium catalyst may contain the above-mentioned glycol component, and the dissolving and diluting components may not be the same component.

Next, polyethylene terephthalate will be described as an example, and the outline of the production method will be described along the direct polymerization method. As a manufacturing method, any of a batch method, a semi-continuous method, and a continuous method can be applied, but the batch method will be described.

The terephthalic acid and ethylene glycol are slurried before being charged into the esterification reaction tank or in the esterification reaction tank. The charged molar ratio of terephthalic acid to ethylene glycol is 1.00 to 1.50. Is preferred for the fluidity of the slurry. Particularly preferably, it is 1.05 to 1.25. In the mixed slurry,
A compound selected from a glycol-soluble magnesium compound, a glycol-soluble manganese compound or a glycol-soluble zinc compound is added, and a glycol-soluble antimony or germanium compound is added as a polymerization catalyst.

Subsequently, the temperature of the reaction vessel is raised to heat the slurry, and the esterification reaction between terephthalic acid and ethylene glycol is started. The reaction is performed while stirring the system. The temperature of the esterification reaction is preferably from 240 to 280C. The reaction pressure is operated under pressure, and is preferably 5 kg / m ² G or less. The reaction proceeds while removing by-product water. When the esterification reaction ends, the distillation of water stops.

Subsequently, the esterified product is transferred to a polycondensation reaction tank, where a phosphorus compound and a nitrogen-containing basic compound are added to improve the heat resistance of the polyester and to further reduce the electric resistivity in an unsolidified state. It is preferably added.
The polycondensation reaction is performed at a temperature of 270 ° C. to 290 ° C. and a pressure of about 0.1 to 2 Torr while removing ethylene glycol.

The glycol-soluble magnesium compound, glycol-soluble manganese compound or glycol-soluble zinc compound used in the present invention includes, for example, organic carboxylate such as acetate, oxalate and benzoate, halide, and hydroxide thereof. Things. Specifically, for example, magnesium acetate, manganese acetate, zinc acetate, magnesium oxalate, manganese oxalate, zinc oxalate, magnesium benzoate, manganese benzoate, zinc benzoate, magnesium chloride, manganese chloride, zinc chloride, zinc bromide Magnesium, manganese bromide, zinc bromide, magnesium hydroxide and the like.

As the phosphorus compound, phosphorous acid, phosphoric acid and / or esters thereof can be used. Specific examples of the phosphorus compound include, for example, phosphorous acid, phosphoric acid,
Examples include trimethyl phosphate, triethyl phosphate, triphenyl phosphate, and mono- or diethyl esters of phosphoric acid or phosphorous acid. As the nitrogen-containing basic compound, a tertiary amine or a quaternary ammonium hydroxide compound, specifically, for example, triethylamine, tributylamine, dimethylaniline, pyridine, quinoline, tetraethylammonium hydroxide, tetrabutylammonium hydroxide, triethylamine Benzyl ammonium hydroxide, 1,8 diazabicyclo (5,4,0) undecene, imidazole and its derivatives, 1,4 diazabicyclo (2,2,2) octane and the like can be mentioned.

[0022]

EXAMPLES The present invention will be described in more detail with reference to the following Examples, but it should not be construed that the invention is limited thereto. Germanium dioxide as a catalyst was charged together with ethylene glycol into a stirring tank equipped with a heating jacket, and heated and dissolved while passing nitrogen gas through. 100 parts by weight of terephthalic acid, ethylene glycol, an ethylene glycol solution of germanium dioxide, and an ethylene glycol solution of a glycol-soluble metal compound were charged into an esterification reactor so that the total amount of ethylene glycol was 59.8 parts by weight, The temperature was raised while the contents were sufficiently stirred to form a slurry, and the reaction temperature was raised to 2 while removing by-product water from the distillation column.
45 ° C was reached.

The reaction was allowed to proceed for 4 hours. After confirming that the by-product of water had substantially stopped, the low-polymer polyester, which was a reaction product, was transferred to a polycondensation reactor, and the nitrogen-containing basic compound and phosphorus were added. Compound was added. After leaving the system with stirring for about 10 minutes, the pressure was gradually reduced to 275.
A polycondensation reaction was carried out at 280 ° C., and the end point of the reaction was judged when the stirrer showed a predetermined torque value, and a polyester was obtained.

The methods for measuring the quality characteristics of the polyesters obtained in the examples and comparative examples are as follows. (1) Intrinsic viscosity (IV) The polyester was prepared by mixing phenol / tetrachloroethane = 3 /
2 (weight ratio) and dissolved at 25 ° C. using an Ubbelohde viscometer. (2) Hue (b value) A chip-shaped polyester was measured with a colorimetric colorimeter (Nippon Denshoku Industries N
D-101D). A larger b value indicates a stronger yellow tint. (3) DEG content After the polyester was decomposed with a methanol solution of sodium hydroxide, it was quantified by gas chromatography and expressed as mol% based on the total glycol component of the polyester.

(4) Electrostatic application characteristics A thin wire electrode is provided between the base of the extruder and the cooling drum, and a DC voltage of 5 kV is applied between the thin wire and the cooling drum to form a film at 50 m / min. It was determined whether the film could be formed favorably at the speed. (5) Number of minute foreign substances in the film After melt-extruding the polyester, it was stretched 3.3 times vertically and horizontally to produce a film having a thickness of 100 μm.
cm ² was observed with a polarizing microscope, and the number of foreign substances having a size of 10 μm or more was determined as follows. ：: The number of foreign substances is 0 to 2 △: The number of foreign substances is 3 to 10 ×: The number of foreign substances is 11 or more

The conditions for dissolving the germanium compound in ethylene glycol and the conditions for adding the solution and other additives such as glycol-soluble metal compounds in the production of the batch polyester of the present invention are described below as Examples and Comparative Examples. Are summarized in Tables 1 to 4. In addition, the esterification and polycondensation conditions for producing the polyesters described in each of the Examples and Comparative Examples were all carried out in accordance with the above-mentioned production conditions. The evaluation results of each quality characteristic of the produced polyester are shown in Table 5.

[0027]

[Table 1]

[0028]

[Table 2]

[0029]

[Table 3]

[0030]

[Table 4]

[0031]

[Table 5]

(Example 1) Germanium dioxide, which is a mixture of hexagonal crystal and amorphous material, is used as a germanium atom in 0.1.
Dispersed in ethylene glycol at a concentration of 6 wt%,
The mixture was heated and stirred at ℃. When the liquid was sampled at 6.5 hours, the liquid was clear. 1.74 parts by weight of the germanium solution was used as a catalyst solution. Further, as a glycol-soluble metal compound, magnesium acetate tetrahydrate 0.0
88 parts by weight, 0.020 parts by weight of phosphoric acid as a phosphorus compound and 0.0035 parts by weight of 1,8 diazabicyclo (5,4,0) undecene as a nitrogen-containing basic compound were added according to the above method.

Example 2 The same germanium dioxide as in Example 1 was heated and stirred at 185 ° C. and completely dissolved in 5 hours. 1.74 parts by weight of this solution was used as a catalyst solution. 0.110 parts by weight of magnesium acetate tetrahydrate as a glycol-soluble metal compound, 0.034 parts by weight of trimethyl phosphate as a phosphorus compound, and 0.0020 parts by weight of 2-ethyl-4-methylimidazole as a nitrogen-containing basic compound were added.

Example 3 The same germanium dioxide as in Example 1 was dispersed as a germanium atom in ethylene glycol at a concentration of 0.3% by weight and heated and stirred at 175 ° C. When sampled for 4.5 hours, it was completely dissolved. 1.74 parts by weight of this solution was used as a catalyst solution. Manganese acetate 4 as a glycol-soluble metal compound
0.101 parts by weight of water salt, phosphoric acid 0.0 as a phosphorus compound
13 parts by weight and 0.0065 parts by weight of 2-ethyl-4-methylimidazole as a nitrogen-containing basic compound were added.

Example 4 The same germanium dioxide as in Example 1 was dispersed in ethylene glycol at a concentration of 0.3 wt% as germanium atoms, and heated and stirred at 190 ° C. When it was sampled for 3.5 hours, it was completely dissolved. 6.96 parts by weight of this solution was used as a catalyst solution. 0.030 parts by weight of zinc acetate dihydrate as a glycol-soluble metal compound, 0.022 parts by weight of triphenyl phosphate as a phosphorus compound, 1,8 as a nitrogen-containing basic compound
0.012 parts by weight of diazabicyclo (5,4,0) undecene was added.

Comparative Example 1 The same germanium dioxide as in Example 1 was dispersed in ethylene glycol at a concentration of 1.0 wt% as germanium atoms, and heated and stirred at 160 ° C. Attempts were made to dissolve it for up to 9 hours, but it could not be completely dissolved and remained cloudy, but 1.04 parts by weight of this solution was used as a catalyst solution. 0.088 parts by weight of magnesium acetate tetrahydrate as a glycol-soluble metal compound, 0.020 parts by weight of phosphoric acid as a phosphorus compound, and 0.0020 parts by weight of 2-ethyl-4-methylimidazole as a nitrogen-containing basic compound were added.

COMPARATIVE EXAMPLE 2 Germanium dioxide containing tetragonal as a main component was dispersed in ethylene glycol at a concentration of 0.6 wt% as germanium atom, and the mixture was heated and stirred at 175 ° C. When the solution was sampled at 6.5 hours, the solution remained cloudy, but as a catalyst solution, the solution was 1.74.
Parts by weight were used. 0.101 parts by weight of manganese acetate tetrahydrate as a glycol-soluble metal compound, 0.020 parts by weight of phosphoric acid as a phosphorus compound, and 0.0020 parts by weight of 2-ethyl-4-methylimidazole as a nitrogen-containing basic compound were added.

Comparative Example 3 The same germanium dioxide as in Example 1 was dispersed in ethylene glycol at a concentration of 0.6 wt% as germanium atom, and heated and stirred at 175 ° C. Sampling at 6.5 hours revealed complete dissolution, but heating was continued for another 10 hours. 1.74 parts by weight of this solution was used as a catalyst solution. Magnesium acetate tetrahydrate 0.2 as a glycol-soluble metal compound
64 parts by weight, trimethyl phosphate 0.0 as a phosphorus compound
85 parts by weight and 0.0035 parts by weight of 1,8-diazabicyclo (5,4,0) undecene as a nitrogen-containing basic compound were added.

Comparative Example 4 The same germanium dioxide as in Example 1 was dispersed as a germanium atom in ethylene glycol at a concentration of 0.6 wt% and heated and stirred at 195 ° C. When sampled at 4.0 hours, it was completely dissolved. 6.09 parts by weight of this solution was used as a catalyst solution. Manganese acetate 4 as a glycol-soluble metal compound
0.023 parts by weight of water salt, 0.044 parts by weight of triphenyl phosphate as a phosphorus compound, and 1,8 diazabicyclo (5,4,0) undecene 0.0 as a nitrogen-containing basic compound
100 parts by weight were added.

Comparative Example 5 The same conditions as in Example 1 were used, except that the amount of 1,8-diazabicyclo (5,4,0) undecene added was 1/4, that is, 0.0009 parts by weight.

Comparative Example 6 The same conditions as in Example 1 were used, except that the amount of the catalyst solution added was 0.44 parts by weight. The polymerization was continued for 5 hours, but the increase in the torque of the stirrer in the polycondensation reaction vessel stopped, and the target degree of polymerization could not be reached.

[0042]

According to the production method of the present invention, the electrostatic application characteristics during film formation are excellent, the amount of foreign matter is small, and the transparency is also excellent.
Suitable as raw material for manufacturing photographic film support,
Polyester can be manufactured.

[Brief description of the drawings]

FIG. 1 is a graph showing the relationship between the addition amount (M) of a glycol-soluble metal atom and the addition amount (P) of a phosphorus compound, showing a region where the electrostatic application characteristics are good.

────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Toshihiro Oda 200 Onakazato, Fujinomiya City, Shizuoka Prefecture Inside Fuji Shashin Film Co., Ltd. (56) References JP-A-1-287133 (JP, A) JP-A-1 -266130 (JP, A) JP-A-1-266129 (JP, A) JP-A-55-115425 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) C08G 63/00- 63/91

Claims (3)

(57) [Claims] 1. An aromatic dicarboxylic acid mainly composed of terephthalic acid and a glycol mainly composed of ethylene glycol as main components, and one or more selected from glycol-soluble magnesium compounds, glycol-soluble manganese compounds and glycol-soluble zinc compounds. When producing a polyester in the presence of a compound, a nitrogen-containing basic compound, and a phosphorus compound, a glycol solution in which a glycol-soluble germanium compound is completely dissolved as a polymerization catalyst is added so as to satisfy the following formula. Characteristic polyester production method. 1.0 <M <8.0 (1) 0.03 <M / P <0.30 (2) 0.02 <A / (M + G) <0.30 (3) 0.27 <G <2. 75 (4) M: Addition amount of magnesium, manganese and zinc atoms to polymer [g atom / t] P: Addition ratio of phosphorus atom to polymer [PPM] A: Number of moles of nitrogen-containing basic compound added to polymer [ Mol / t] G: amount of germanium atom added to polymer [g atom / t] 2. The composition of a germanium compound having a germanium atom content of 0.2 wt% or more with respect to ethylene glycol.
The method for producing a polyester according to claim 1, wherein an ethylene glycol solution completely dissolved within a period of 8 hours at a temperature of 165 ° C to 195 ° C at a concentration of 7% by weight or less is used as a catalyst solution. 3. An ethylene glycol solution of a completely dissolved germanium compound is reacted with an aromatic dicarboxylic acid mainly composed of terephthalic acid and a glycol mainly composed of ethylene glycol before substantially starting an esterification reaction. The method for producing a polyester according to claim 1, wherein the polyester is added to a system.