JP2010260953A - Polyester composition and polyester film - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a polyester film using a polyester which is produced by using a new polyester polycondensation catalyst containing no conventional polycondensation catalyst such as an antimony compound and a germanium compound as main components, and has satisfactory degree of polymerization and thermal stability and wherein flocculation of inorganic particles is suppressed, nearly free from clogging of a filter, having excellent sliding properties, running properties and wear resistance and nearly free from reduction of quality due to a defect and a foreign matter on the film. <P>SOLUTION: A polyester composition polymerized by using a polycondensation catalyst containing an aluminum compound and a lithium compound contains 0.01 to 1.0 wt.% inert inorganic particles having 0.5 to 3.0 mμ average particle diameter and ≤1,000/mm<SP>2</SP>coarse particles having ≥10 μm size. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a polyester composition polymerized using a novel polyester polycondensation catalyst and an oriented polyester film comprising the same as a main constituent, and more specifically, germanium and an antimony compound are not used as catalyst main components. The present invention relates to a polyester composition polymerized using a novel aluminum-based polycondensation catalyst and an oriented polyester film comprising the same as a main constituent.

  Polyesters typified by polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polyethylene naphthalate (PEN), etc. are excellent in mechanical properties and chemical properties. Depending on the properties of each polyester, for example, It is widely used in various fields such as fibers for clothing and industrial materials, various films and sheets for packaging and industrial use, and molded products such as bottles and engineering plastics.

  For example, in the case of polyethylene terephthalate (PET), a polyester mainly composed of aromatic dicarboxylic acid and alkylene glycol, which is a typical polyester, is obtained by esterification or transesterification of terephthalic acid or dimethyl terephthalate and ethylene glycol. Bis (2-hydroxyethyl) terephthalate is produced and industrially produced by a polycondensation method or the like in which polycondensation is performed using a catalyst at high temperature and under vacuum.

  Conventionally, antimony trioxide has been widely used as a polyester polymerization catalyst used in such polycondensation of polyester. Antimony trioxide is a polycondensation catalyst that is inexpensive and has excellent catalytic activity. However, when it is used in an amount of such a main component, that is, a practical polymerization rate, it can be used during polycondensation. Since metal antimony precipitates and the appearance of polyester is darkened, it is not preferable. Moreover, the foreign material resulting from metal antimony arises and it is unpreferable in the use with a severe request | requirement of a fault. Therefore, a polyester that does not contain antimony as a main catalyst component is desired.

  When used for a film, the precipitation of metal antimony in the polyester not only causes the die die to become dirty during melt extrusion, but also causes the surface defects of the film. Further, further improvements are demanded in applications where the demands on transparency and color tone are severe.

  As a method for solving the above problems, attempts have been made to use antimony trioxide as a polycondensation catalyst and to suppress the darkening of PET and the generation of foreign substances. For example, in patent document 1, the production | generation of the black foreign material in PET is suppressed by using the compound of antimony trioxide, bismuth, and selenium as a polycondensation catalyst. Patent Document 2 states that when antimony trioxide containing an oxide of sodium and iron is used as a polycondensation catalyst, precipitation of metal antimony is suppressed. However, these polycondensation catalysts cannot achieve the purpose of reducing the content of antimony in the polyester after all.

  Studies on polycondensation catalysts that replace antimony-based catalysts such as antimony trioxide have also been conducted, and titanium compounds and tin compounds typified by tetraalkoxy titanates have already been proposed. However, polyesters produced using these materials are susceptible to thermal degradation during melt molding, and the polyesters are remarkably colored.

  As an attempt to overcome such problems when a titanium compound is used as a polycondensation catalyst, for example, Patent Document 3 proposes a method of using tetraalkoxy titanate simultaneously with a cobalt salt and a calcium salt. Further, according to Patent Document 4, a method of using tetraalkoxy titanate as a polycondensation catalyst simultaneously with a cobalt compound and using a fluorescent brightening agent has been proposed. However, with these techniques, although coloring of PET when tetraalkoxy titanate is used as a polycondensation catalyst is reduced, it has not been achieved to effectively suppress thermal decomposition of PET.

  As another attempt to suppress thermal degradation during melt molding of a polyester polymerized using a titanium compound as a polycondensation catalyst, for example, in Patent Document 5, a phosphorus compound is added after polymerizing a polyester using a titanium compound as a catalyst. A method is disclosed. However, it is not only technically difficult to effectively add the additive to the polymer after polymerization, but also the cost is increased and it is not put into practical use.

  As a polycondensation catalyst that gives a polyester having excellent catalytic activity other than the antimony compound and does not have the above problems, a germanium compound has already been put into practical use, but this catalyst is very expensive. However, since it tends to distill out of the reaction system during the polymerization, there is a problem that the concentration of the catalyst in the reaction system changes and it is difficult to control the polymerization.

  A technique for producing a polyester polycondensation catalyst having sufficient catalytic activity by using an alkali metal compound in combination with an aluminum compound has been disclosed (see, for example, Patent Documents 6, 7, 8, 9, and 10). When the above polycondensation catalyst is used, a polyester having a sufficiently satisfactory degree of polymerization can be polymerized relatively efficiently, which is an economically advantageous method. Patent Document 8 discloses a technique for improving the color tone by adding a specific transition metal element nitride, boride, or carbide in addition to the high catalytic activity of polyester. Patent Document 9 discloses a technique for improving the color tone by adding a phosphorus compound in addition to aluminum and an alkaline earth metal or alkali metal. Patent Document 10 discloses a technique for improving the color tone by adding a magnesium compound or a specific organic phosphorus compound in addition to aluminum and an alkali metal compound.

  When film is overlaid on polyester for film, the film adheres, so-called blocking occurs, and when processing a roll-shaped film, defects such as scratches occur due to poor sliding properties with guide rolls, etc. There is a problem to do. In order to solve such a problem in handling the film, a technique of incorporating inert particles such as inorganic particles inside the polyester is used. As a method of incorporating inorganic particles and the like inside the polyester, there are a method of adding inorganic particles and the like at an arbitrary stage during polyester polymerization, and a method of adding inorganic particles and the like to the finished polyester resin later by melt kneading. From the viewpoint of dispersibility of the inorganic particles, addition during polymerization is preferable. However, even in the case of addition during polymerization, aggregation of inorganic particles is an unavoidable problem. Therefore, various contrivances have been made on the characteristics of inorganic particles and the method of adding particles during polymerization (for example, see Patent Documents 11, 12, and 13). According to the above publication, the best way to prevent the aggregation of inorganic particles is to add surface treatment to the inorganic particles and then add the polycondensation catalyst and the inorganic particles separately, and further finely the particles themselves. It has been reported that adding separately is effective.

  The inventors of the present invention have tried to polymerize a polyester by using a polymerization technique in consideration of aggregation prevention with a conventional Sb catalyst in addition to the polycondensation catalyst techniques of Patent Documents 6 and 7, and contrary to conventional knowledge. On the contrary, it was confirmed that the problem of aggregation of the inorganic particles becomes remarkable. That is, when polymerizing a polyester using a polycondensation catalyst composed of an aluminum compound and an alkali metal compound, it was confirmed that the inorganic particles were significantly aggregated when the addition of the catalyst and the addition of inorganic particles were separated. . Recognizing for the first time that solving this problem is an important issue.

  On the other hand, a technique of adding a specific phosphorus compound to an aluminum compound to obtain a polyester polycondensation catalyst having sufficient catalytic activity is also known (see, for example, Patent Document 14). However, when the above polyester polycondensation catalyst is used, a polyester having excellent thermal stability can be obtained. However, when inorganic particles are added, the catalytic activity tends to decrease, and in order to polymerize a polyester having a satisfactory degree of polymerization. It took a lot of polymerization time and had practical problems.

  As described above, it is a polycondensation catalyst for polyesters mainly composed of metal components other than antimony compounds, germanium compounds, titanium compounds, or tin compounds, and has excellent catalytic activity and contains inorganic particles. Polyester polycondensation catalysts and polycondensation techniques for polyesters that have little decrease in activity and little coarse particles due to aggregation of inorganic particles, and polyester compositions suitable for film applications using the same are desired.

Japanese Patent No. 2666502 JP 9-291141 A JP-A-55-116722 JP-A-8-73581 JP-A-10-259296 JP 2000-302854 A JP 2001-26639 A International Publication No. 07/035250 Pamphlet International Publication No. 07/035256 Pamphlet International Publication No. 07/012731 Pamphlet Japanese Patent Publication No.59-46254 JP 59-179555 A Japanese Patent Publication No. 63-30335 JP 2001-131276 A

  The object of the present invention is to produce a novel polyester polycondensation catalyst which does not contain a polycondensation catalyst such as a conventional antimony compound or germanium compound as a main component, has a sufficient degree of polymerization and thermal stability, and is inorganic. Polyester with reduced aggregation of particles. When used in polyester film, etc., there is little clogging of the filter, excellent slipperiness, running performance, and wear resistance, and little deterioration in quality due to defects on the film or foreign matter. A polyester film is provided.

  As a result of intensive studies aimed at solving the above-mentioned problems, the present inventors have used a specific aluminum compound in combination with a specific alkali metal compound, thereby far exceeding those obtained by adding their individual catalytic activities. It has been found that a large catalytic activity can be provided. Further, it has been found that when the polycondensation catalyst of the present invention is used, a polyester having a small amount of coarse particles due to aggregation of inorganic particles can be obtained with little decrease in catalytic activity when inorganic particles are added.

That is, the present invention
(1) A polyester composition polymerized using a polycondensation catalyst containing an aluminum compound and a lithium compound, and 0.01 to 1 inert inorganic particles having an average particle size of 0.5 to 3.0 μm A polyester composition characterized by containing 0.0% by weight and the number of coarse particles of 10 μm or more is 1000 / mm ² or less,
(2) A polyester composition polymerized using a polycondensation catalyst containing an aluminum compound and a lithium compound, and the solution and the average particle size of the lithium compound are 0 when the esterification reaction is substantially completed. The mixed liquid prepared by mixing a slurry of inert inorganic particles having a diameter of 0.5 to 3.0 μm in advance outside the system is added to the reaction system, and then the polycondensation reaction is completed. It is a polyester composition.

  The polyester composition of the present invention is produced using a novel catalyst having a component other than an antimony compound or a germanium compound as a main component and having excellent catalytic activity, and the dispersibility of the inorganic particles added during the production is good. Therefore, the film using the polyester of the present invention is excellent in running property, abrasion resistance, optical properties and the like, and can be used for a wide range of applications such as packaging films and industrial films.

  The polyester composition of the present invention forms an irregular surface on the surface during film formation, and improves the handling characteristics such as slipperiness, running performance, wear resistance, and winding property, and is an inert inorganic substance in the polyester polymerization process. Particles are added. In general, as a technique for forming irregularities on the surface of a polyester film, an external particle addition method in which inorganic and / or heat-resistant polymer resin particles are added in a polymerization process of the polyester, a catalyst residue and a polyester component are reacted in the polymerization process. An internal particle method for precipitating insoluble particles, a method for containing the particles in the coating layer, a method for embossing with a roll having irregularities on the surface of the thin film layer, a method for patterning surface irregularities with a laser beam, In view of production efficiency and quality stability, the method of adding inert particles in the polyester polymerization step as in the present invention is most preferable.

  As the inert particles added to the polyester according to the present invention, the inorganic particles exemplified below are preferable in that the effect of preventing aggregation of the inert particles described later can be effectively exhibited.

  The polycondensation catalyst used when polymerizing the polyester composition of the present invention is a catalyst containing an aluminum compound and a lithium compound.

  In the polyester composition of the present invention, the concept of a preferable means for achieving aggregation of inorganic particles using an aluminum compound and a lithium compound as a polycondensation catalyst will be described. In general, it is known that an aluminum element has an action of binding to inorganic fine particles to form an aggregate. Also in the aluminum compound added as a catalyst at the time of polymerizing polyester, it has been found that the conventionally known polyester polymerization method has the effect of agglomerating inorganic particles to produce coarse particles in addition to the catalytic action. In developing the measures for obtaining the polyester of the present invention, it has become possible to achieve it for the first time by applying an achievement means based on the completely opposite idea to the conventionally known polyester polymerization technique. That is, the concept of the achievement means for obtaining the polyester of the present invention is that the polycondensation catalyst composed of an aluminum compound and a lithium compound includes a lithium compound and inorganic particles dispersed in a dispersion medium such as glycol. It has been found that this can be achieved by simultaneously adding to the polyester polymerization system. The reason why the aggregation of inorganic particles can be suppressed by the above method is considered to be the dispersion effect of inorganic particles by lithium or a compound thereof. The dispersion action of this lithium compound is considered to be the effect of lithium ions. A similar dispersion effect can be obtained even if a metal compound other than lithium, which has a strong monovalent ionization tendency, is mixed with inorganic particles in advance and polymerized simultaneously with the catalyst or separately. Inorganic particles and a lithium compound may be mixed in advance and added to a polymerization system to which an aluminum compound has been added.

  Furthermore, in the polyester composition of the present invention, as a preferable achievement means for suppressing aggregation of inorganic particles using an aluminum compound and a lithium compound as a polycondensation catalyst, the affinity between the aluminum compound and glycol which is a polyester raw material is increased. Can be mentioned. Usually, an aluminum compound has poor affinity with a glycol component forming a polyester composition, particularly ethylene glycol. Therefore, in order to increase the affinity, for example, the aluminum compound is once dissolved in water to form an aqueous solution of the aluminum compound. There is a method of removing water out of the system by adding ethylene glycol. At this time, it is necessary to devise not to give heat as much as possible so as not to impair the catalytic activity of the aluminum compound. For example, dehydrating over a long time under reduced pressure.

  Below, the aluminum compound, lithium compound and inorganic particles of the present invention will be described, and the best mode of polymerization will be described.

  As the aluminum compound of the present invention, a known aluminum compound can be used in addition to metal aluminum.

  Specific examples of the aluminum compound of the present invention include aluminum formate, aluminum acetate, basic aluminum acetate, aluminum propionate, aluminum oxalate and other carboxylates, aluminum chloride, aluminum hydroxide, aluminum hydroxide chloride, aluminum carbonate Inorganic acid salts such as, aluminum alkoxides such as aluminum methoxide and aluminum ethoxide, aluminum chelate compounds such as aluminum acetylacetonate and aluminum acetylacetate, organoaluminum compounds such as trimethylaluminum and triethylaluminum and their partial hydrolysates Etc. Of these, carboxylates, inorganic acid salts and chelate compounds are preferred, and among these, aluminum acetate, basic aluminum acetate, aluminum chloride, aluminum hydroxide, aluminum hydroxide chloride and aluminum acetylacetonate are particularly preferred.

  The addition amount of the aluminum compound is preferably 0.001 to 0.05 mol%, more preferably, based on the number of moles of all constituent units of the carboxylic acid component such as dicarboxylic acid or polycarboxylic acid of the obtained polyester. 0.005 to 0.02 mol%. If the addition amount is less than 0.001 mol%, the catalytic activity may not be sufficiently exerted. If the addition amount is 0.05 mol% or more, the thermal stability or thermal oxidation stability is deteriorated, resulting from aluminum. Occurrence of foreign matters or increased coloring may be a problem. As described above, the polymerization catalyst of the present invention has a great feature in that it exhibits a sufficient catalytic activity even when the addition amount of the aluminum component is small. As a result, thermal stability and thermal oxidation stability are excellent, and foreign matters and coloring caused by aluminum can be reduced.

  The lithium compound of the present invention includes, for example, saturated aliphatic carboxylates such as lithium formic acid, acetic acid, propionic acid, butyric acid and succinic acid, unsaturated aliphatic carboxylates such as acrylic acid and methacrylic acid, and benzoic acid. Aromatic carboxylates, halogen-containing carboxylates such as trichloroacetic acid, hydroxycarboxylates such as lactic acid, citric acid and salicylic acid, inorganic acid salts such as carbonic acid and sulfuric acid, organic sulfates such as lauryl sulfuric acid, methoxy and ethoxy Examples thereof include chelate compounds such as alkoxide and acetylacetonate, hydrides, oxides, hydroxides and the like. Among these lithium compounds, when strongly alkaline ones such as hydroxides are used, the polyester tends to be susceptible to hydrolysis. Accordingly, the lithium compound of the present invention is preferably a lithium saturated aliphatic carboxylate, unsaturated aliphatic carboxylate, aromatic carboxylate, halogen-containing carboxylate from the viewpoint of not promoting the hydrolysis of the polyester. Hydroxycarboxylates, inorganic acid salts, organic sulfates, chelate compounds, and oxides. Of these, lithium saturated aliphatic carboxylates, particularly lithium acetate, are preferred from the standpoint of ease of handling and availability.

  The use amount of the lithium compound of the present invention is preferably 0.005 to 0.2 mol% based on 1 mol of all constituent units of carboxylic acid components such as dicarboxylic acid and polyvalent carboxylic acid of the polyester obtained by polymerization. More preferably, it is 0.01 to 0.1 mol%.

  To the polyester of the present invention, a metal compound other than an aluminum compound and a lithium compound can be added as a co-catalyst as long as the purpose is not impaired. Examples of other metal compounds include magnesium compounds, sodium compounds, and phosphorus compounds.

  The polyester according to the present invention can be produced by a conventionally known method. For example, either a method of polycondensation after esterification of terephthalic acid and ethylene glycol, or a method of polycondensation after transesterification of an alkyl ester of terephthalic acid such as dimethyl terephthalate with ethylene glycol It can also be done by the method. The polymerization apparatus may be a batch type or a continuous type.

  The catalyst of the present invention has catalytic activity not only for polycondensation but also for esterification and transesterification. The transesterification reaction between an alkyl ester of a dicarboxylic acid such as dimethyl terephthalate and a glycol such as ethylene glycol is usually carried out in the presence of a transesterification catalyst such as zinc. The catalyst of the present invention is used in place of these catalysts. You can also. The catalyst of the present invention has catalytic activity not only in melt polymerization but also in solid phase polymerization or solution polymerization.

  The polyester polymerization catalyst used in the present invention can be added to the reaction system at any stage of the polymerization reaction. For example, it can be added to the reaction system at any stage before and during the esterification reaction or transesterification reaction, immediately before the start of the polycondensation reaction, or at any stage during the polycondensation reaction. In particular, the aluminum compound, lithium compound, and inorganic particles of the present invention are preferably added immediately before the start of the polycondensation reaction.

  The polyester of the present invention comprises one or two or more selected from polyvalent carboxylic acids containing dicarboxylic acids and their ester-forming derivatives and one or more selected from polyhydric alcohols containing glycols, Or what consists of hydroxycarboxylic acid and these ester-forming derivatives, or what consists of cyclic ester.

  Preferred polyesters are those in which the main acid component is terephthalic acid or an ester-forming derivative thereof, or naphthalene dicarboxylic acid or an ester-forming derivative thereof, and the main glycol component is alkylene glycol.

  The polyester whose main acid component is terephthalic acid or its ester-forming derivative or naphthalene dicarboxylic acid or its ester-forming derivative is terephthalic acid or its ester-forming derivative and naphthalene dicarboxylic acid or its ester formation with respect to all acid components It is preferable that it is polyester containing 70 mol% or more in total of the functional derivatives, more preferably polyester containing 80 mol% or more, and still more preferably polyester containing 90 mol% or more.

  The polyester whose main glycol component is an alkylene glycol is preferably a polyester containing 70 mol% or more of the total amount of alkylene glycol with respect to all glycol components, more preferably a polyester containing 80 mol% or more, More preferably, it is a polyester containing 90 mol% or more.

  Dicarboxylic acids include succinic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, decanedicarboxylic acid, dodecanedicarboxylic acid, tetradecanedicarboxylic acid, hexadecanedicarboxylic acid, 1,3 -For cyclobutanedicarboxylic acid, 1,3-cyclopentanedicarboxylic acid, 1,2-cyclohexanedicarboxylic acid, 1,3-cyclohexanedicarboxylic acid, 1,4-cyclohexanedicarboxylic acid, 2,5-norbornanedicarboxylic acid, dimer acid, etc. Saturated aliphatic dicarboxylic acids exemplified, or ester-forming derivatives thereof, unsaturated aliphatic dicarboxylic acids exemplified by fumaric acid, maleic acid, itaconic acid, etc., or ester-forming derivatives thereof, orthophthalic acid, isophthalic acid, terephthalic acid Acid, 5 (Alkali metal) sulfoisophthalic acid, diphenic acid, 1,3-naphthalenedicarboxylic acid, 1,4-naphthalenedicarboxylic acid, 1,5-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, 2,7-naphthalenedicarboxylic acid 4,4′-biphenyldicarboxylic acid, 4,4′-biphenylsulfonedicarboxylic acid, 4,4′-biphenyletherdicarboxylic acid, 1,2-bis (phenoxy) ethane-p, p′-dicarboxylic acid, pamoic acid , Aromatic dicarboxylic acids exemplified by anthracene dicarboxylic acid and the like, or ester-forming derivatives thereof.

  Of these dicarboxylic acids, terephthalic acid, naphthalenedicarboxylic acid, or ester-forming derivatives thereof are preferred.

  Naphthalenedicarboxylic acid or its ester-forming derivatives include 1,3-naphthalenedicarboxylic acid, 1,4-naphthalenedicarboxylic acid, 1,5-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, and 2,7-naphthalenedicarboxylic acid. Examples include acids, or ester-forming derivatives thereof.

  Particularly preferred are terephthalic acid, 2,6-naphthalenedicarboxylic acid or ester-forming derivatives thereof. If necessary, other dicarboxylic acids may be used as components.

  As polyvalent carboxylic acids other than these dicarboxylic acids, ethanetricarboxylic acid, propanetricarboxylic acid, butanetetracarboxylic acid, pyromellitic acid, trimellitic acid, trimesic acid, 3,4,3 ′, 4′-biphenyltetracarboxylic acid, And ester-forming derivatives thereof.

  Examples of the glycol include ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, diethylene glycol, triethylene glycol, 1,2-butylene glycol, 1,3-butylene glycol, 2,3-butylene glycol, 1, 4-butylene glycol, 1,5-pentanediol, neopentyl glycol, 1,6-hexanediol, 1,2-cyclohexanediol, 1,3-cyclohexanediol, 1,4-cyclohexanediol, 1,2-cyclohexanedi Alkylene glycol such as methanol, 1,3-cyclohexanedimethanol, 1,4-cyclohexanedimethanol, 1,4-cyclohexanediethanol, 1,10-decamethylene glycol, 1,12-dodecanediol, poly Aliphatic glycols exemplified by tylene glycol, polytrimethylene glycol, polytetramethylene glycol, hydroquinone, 4,4′-dihydroxybisphenol, 1,4-bis (β-hydroxyethoxy) benzene, 1,4-bis ( β-hydroxyethoxyphenyl) sulfone, bis (p-hydroxyphenyl) ether, bis (p-hydroxyphenyl) sulfone, bis (p-hydroxyphenyl) methane, 1,2-bis (p-hydroxyphenyl) ethane, bisphenol A , Bisphenol C, 2,5-naphthalenediol, and glycols obtained by adding ethylene oxide to these glycols, and the like.

  Among these glycols, alkylene glycol is preferable, and ethylene glycol, 1,3-propylene glycol, 1,4-butylene glycol, and 1,4-cyclohexanedimethanol are more preferable. The alkylene glycol may contain a substituent or an alicyclic structure in the molecular chain, and two or more kinds may be used at the same time.

  Examples of polyhydric alcohols other than these glycols include trimethylolmethane, trimethylolethane, trimethylolpropane, pentaerythritol, glycerol, hexanetriol and the like.

  Examples of the hydroxycarboxylic acid include lactic acid, citric acid, malic acid, tartaric acid, hydroxyacetic acid, 3-hydroxybutyric acid, p-hydroxybenzoic acid, p- (2-hydroxyethoxy) benzoic acid, 4-hydroxycyclohexanecarboxylic acid, or these And ester-forming derivatives thereof.

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

  Examples of ester-forming derivatives of polyvalent carboxylic acids or hydroxycarboxylic acids include these alkyl esters, acid chlorides, acid anhydrides, and the like.

  As the polyester used in the present invention, polyethylene terephthalate, polybutylene terephthalate, polypropylene terephthalate, poly (1,4-cyclohexanedimethylene terephthalate), polyethylene naphthalate, polybutylene naphthalate, polypropylene naphthalate and copolymers thereof are preferable. Particularly preferred are polyethylene terephthalate and copolymers thereof.

  The average particle diameter of the inorganic particles added to the polyester in the present invention is 0.5 to 3.0 μm, more preferably 0.8 to 2.5 μm. If it is less than 0.5 μm, the effect of forming irregularities on the surface and imparting handling properties such as slipperiness and running properties is unfavorable. On the other hand, if it exceeds 3.0 μm, the quality of the film may be impaired by the formation of coarse protrusions, which is not preferable.

  The average particle diameter referred to in the present invention is determined from a particle size distribution measured by a laser light scattering method using water or ethylene glycol as a medium.

  In the present invention, the amount of the inorganic particles added to the polyester is preferably in the range of 0.02 to 2.0 wt%, more preferably in the range of 0.1 to 1.0 wt% with respect to the polyester. If it is less than 0.02 wt%, it is insufficient to give the slipperiness and running property of the film. On the other hand, if it exceeds 2.0 wt%, the effect of preventing coarse particles is not sufficient, and the generation of foreign matters when used as a film is a problem, which is not preferable.

  As the inorganic particles used in the present invention, particles made of metal oxides such as titanium, aluminum, silicon, calcium, magnesium and barium, carbonates, silicates, sulfates and aluminates can be used.

  Specific examples include titanium dioxide, alumina, aluminosilicate, silicon dioxide, calcium oxide, calcium carbonate, barium sulfate, and other natural particles such as talc, mica, kaolinite, and zeolite. Not.

  These inorganic particles are slurried with glycols to prevent agglomeration, and then mechanically dispersed with a media agitation disperser such as a sand grinder, attritor, or ultrasonic wave, and alkali metal compounds, ammonium compounds, and phosphorus compounds are added. It is more preferable to add after improving the dispersion efficiency. The addition timing of the above-mentioned inorganic particles is not particularly limited, but is preferably added to the polyester reaction system after the glycol compound or slurry of the aluminum compound and phosphorus compound which are the catalyst of the present invention is added. Is a preferred embodiment.

  In the polyester used in the present invention, inactive particles such as inorganic particles, heat-resistant polymer particles, and crosslinked polymer particles, fluorescent whitening agents, ultraviolet light-inhibiting agents, infrared-absorbing dyes, thermal stability, depending on the purpose of use. 1 type, or 2 or more types of various additives, such as an agent, surfactant, and antioxidant, can be contained. As the antioxidant, antioxidants such as aromatic amines and phenols can be used. As stabilizers, phosphoric acid and phosphoric acid ester-based phosphorous, sulfur-based, amine-based stabilizers, etc. Can be used.

  In order to describe the polyester of the present invention in more detail, an example of a method for producing polyethylene terephthalate will be described below. The method for producing the polyester of the present invention is not limited to the following.

  In the present invention, it is preferable to carry out the polyester by a direct esterification method and a continuous method.

  The direct esterification method is advantageous in terms of economy as compared with the transesterification method. The continuous polycondensation method is advantageous in terms of quality uniformity and economy as compared to the batch polycondensation method.

  In the present invention, the number and size of the reactors in the esterification and polycondensation steps, the production conditions in each step, and the like can be appropriately selected without limitation.

  For example, a slurry containing 1.02 to 2.0 moles, preferably 1.03 to 1.95 moles of ethylene glycol per mole of terephthalic acid is prepared and used in the esterification reaction step. Supply continuously. The esterification reaction is preferably carried out using a multistage apparatus in which two or more esterification reaction tanks are connected in series while removing water generated by the reaction from the system with a rectification column. The temperature of the esterification reaction in the first stage is 240 to 270 ° C., preferably 245 to 265 ° C., and the pressure is normal pressure to 0.29 MPa, preferably 0.005 to 0.19 MPa. The temperature of the esterification reaction at the final stage is usually 250 to 290 ° C, preferably 255 to 275 ° C, and the pressure is usually 0 to 0.15 MPa, preferably 0 to 0.13 MPa. When carried out in three or more stages, the reaction conditions for the esterification reaction in the intermediate stage are conditions between the reaction conditions for the first stage and the reaction conditions for the final stage. The increase in the reaction rate of these esterification reactions is preferably distributed smoothly at each stage. Ultimately, it is desirable that the esterification reaction rate reaches 90% or more, preferably 93% or more. A low-order condensate having a molecular weight of about 500 to 2000 is obtained by these esterification reactions. Subsequently, it is transferred to a polycondensation reaction tank to carry out polycondensation. The number of reaction tanks in the polycondensation step is not limited. In general, a three-stage system of initial polycondensation, intermediate polycondensation and late polycondensation is employed. As for the polycondensation reaction conditions, the reaction temperature of the first stage polycondensation is 250 to 290 ° C., preferably 260 to 280 ° C., and the pressure is 0.065 to 0.0026 MPa, preferably 200 to 20 Torr. The temperature of the polycondensation reaction is 265 to 300 ° C., preferably 275 to 295 ° C., and the pressure is 0.0013 to 0.000013 MPa, preferably 0.00065 to 0.000065 MPa. When carried out in three or more stages, the reaction conditions for the intermediate stage polycondensation reaction are conditions between the reaction conditions for the first stage and the reaction conditions for the last stage. The degree of increase in intrinsic viscosity achieved in each of these polycondensation reaction steps is preferably distributed smoothly.

  The polymerization catalyst and inorganic particles of the present invention are continuously added in a quantitative amount from the final stage of the esterification reaction tank to the reaction product during the transfer to the first stage polycondensation reaction tank. It is preferable. In addition, an ethylene glycol solution of an aluminum compound, an ethylene glycol solution of a lithium compound, and an ethylene glycol slurry of inorganic particles are mixed, and the one-component medium is subjected to an esterification reaction via a stirring device such as an in-line mixer. After being added to and blended with the reactant transferred from the final stage to the polycondensation reaction step, it is sent to the polycondensation reaction tank to complete the polycondensation.

  A method for measuring the number of coarse particles by aggregation of inorganic particles in the polyester composition of the present invention will be described below.

  The measurement of the number of coarse particles in the polyester composition of the present invention uses a method of measuring the size and number of particles by image analysis from the image of particles in a polymer observed using a phase contrast optical microscope. A phase-contrast optical microscope can convert a slight delay (phase difference) in the wavelength of light transmitted through an object with a different refractive index into light and dark contrast using light diffraction and refraction. Suitable for observing inorganic particles that appear colorless and transparent in the polymer. The observed image can be taken into an image analysis apparatus as electronic data, and the particle diameter (area circle equivalent diameter) and number can be measured.

  When observing coarse particles with a phase-contrast microscope, the field of view and the depth of focus are determined by the magnification and aperture of the lens used. In addition, in the case of a sample having a large content of inorganic particles and a low light transmittance, the brightness of the obtained image is dark, and there are cases where sufficient observation cannot be performed with a lens having a large magnification. Moreover, the thickness of the sample to be observed needs to be sufficiently thick with respect to the focal depth of the objective lens. In order to satisfy these conditions, in the present invention, the phase contrast objective lens of the phase contrast microscope is observed using a lens having a magnification of 10 times and an aperture of 0.5.

Measurement by the image analysis apparatus is performed according to the following procedure.
(1) The obtained image is converted into an electronic signal. The converted image data is a monochrome image, and the contrast of the image is composed of 256 gradations from 0 (black) to 255 (white).
(2) A binarization process is performed to clearly separate the boundary between the object of the image (coarse inorganic particles) and the background (polymer), the particles are white, the background is black (or vice versa, the particles are black, the background Is white).
(3) The particle diameter (area circle equivalent diameter) and number are calculated from the number of dots (dots) constituting the image.
The obtained results are data in which the unit area is converted according to the actual scale of the image and the number is divided for each particle size.
The measurement is usually performed in 20 to 40 fields of view, and the measurement results are used after being converted per field area of 1 mm2.
In observation and measurement, it is preferable to appropriately adjust the density and resolution of the image and the threshold for binarization using a standard sample with a known particle diameter and number of particles.

  In the polyester composition of the present invention, the number of coarse particles having a particle diameter of 10 μm or more measured by the above method needs to be 1000 or less per square mm. If the number of coarse particles exceeds 1000, not only the surface of the film becomes a foreign object, but the appearance and quality are impaired, and the back pressure of the filter increases and the filter is clogged during the melting process when manufacturing polymers and films. As a result, long-term stable production is not possible.

In order to give the film sufficient slipperiness and processability, and to have a good appearance and quality when the above film is formed, and to satisfy stable productivity, the number of coarse particles of the polyester of the present invention preferably is 10 to 100 / mm ^2.

  Next, an example of the manufacturing method of the film using the polyester composition of this invention is demonstrated below. The manufacturing method of a polyester film is not limited to the following. The polyester resin polymerized using the specific catalyst is melt-extruded and formed into a sheet shape on a cooling rotary roll from a T-die to create an unstretched sheet. In this case, for example, by applying the technique described in Japanese Patent Publication No. 6-39521 and Japanese Patent Publication No. 6-45175, high-speed film formation is possible. Moreover, it is good also as a laminated | multilayer film by a co-extrusion method, using a several extruder, assigning various functions to a core layer and a skin layer.

  The oriented polyester film can be obtained by stretching 1.1 to 6 times at least in the uniaxial direction at a temperature not less than the glass transition temperature of the polyester and less than the crystallization temperature using a known method.

  For example, in the case of producing a biaxially oriented polyester film, a sequential biaxial stretching method in which uniaxial stretching is performed in the longitudinal direction or the transverse direction, and then stretching in the orthogonal direction, and a simultaneous biaxial stretching method in which stretching is performed simultaneously in the longitudinal direction and the transverse direction. In addition to using a linear motor as the driving method for simultaneous biaxial stretching, several times in the same direction, such as horizontal / longitudinal / longitudinal stretching, longitudinal / horizontal / longitudinal stretching, and longitudinal / vertical / horizontal stretching It is possible to adopt a multistage stretching method in which the stretching is performed separately.

  Further, after the completion of stretching, in order to reduce the thermal shrinkage rate of the film, a heat setting treatment is performed at a temperature of (melting point−50 ° C.) to less than the melting point within 30 seconds, preferably within 10 seconds. % Longitudinal relaxation treatment, lateral relaxation treatment, etc. are preferably performed.

  It is preferable that the thickness of the obtained oriented polyester film is 1-1000 micrometers, More preferably, it is 5-500 micrometers, More preferably, it is 10-200 micrometers. If it is less than 1 μm, it is difficult to handle because there is no waist. On the other hand, if it exceeds 1000 μm, it is too hard to handle.

  In addition, in order to provide various functions such as adhesion, releasability, antistatic, infrared absorption, antibacterial properties, scratch resistance, etc., the surface of the oriented polyester film may be coated with a polymer resin by a coating method. Good. Moreover, it is good also as a slippery highly transparent polyester film by making an inorganic and / or organic particle | grain contain only in a coating layer. Furthermore, an inorganic vapor deposition layer can be provided to provide various barrier functions such as oxygen, water, and oligomer, or a conductive layer can be provided by a sputtering method or the like to provide conductivity.

EXAMPLES Hereinafter, although an Example demonstrates this invention, this invention is not limited to these Examples from the first. In addition, the evaluation method used in each Example and the comparative example is demonstrated below.
In the following description, it is simply described as “polyester”, but it is actually a “polyester composition” containing a catalyst component and inorganic particles.

〔Evaluation methods〕
(1) Intrinsic viscosity of polyester (IV)
The polyester was dissolved using a 6/4 (weight ratio) mixed solvent of phenol / 1,1,2,2-tetrachloroethane and measured at a temperature of 30 ° C.

(2) Average particle size of inorganic particles Using a laser light scattering particle size distribution meter (Leeds & Northrup, Microtrac HRA model 9320-X100), the ethylene glycol slurry of inorganic particles is diluted with water and measured in an aqueous system. did. The 50% cumulative volume diameter of the measurement results was taken as the average particle diameter.

(3) Number of coarse particles in polyester (IMA coarse particle measurement method)
One polyester chip is sandwiched between two cover glasses (Matsunami micro cover glass, 25 mm × 25 mm, thickness 0.2 mm), heated and melted on a hot plate at about 300 ° C., and 0.8 to 0.9 mm It was pressed into a thickness and immediately cooled immediately to obtain an observation sample. The central part of the thickness of the sample was observed using a phase-contrast microscope (manufactured by Nikon) and an objective lens (manufactured by Nikon, magnification 10 ×, aperture 0.5). The image was taken into an image analysis apparatus (manufactured by Nireco, Luzex-FS) via a CCD camera, image analysis was performed, and the number of particles of 10 μm or more was measured. The same measurement was performed 20 times while changing the field of view, the total number of particles was determined, and the number of particles of 10 μm or more per 1 square mm of the field of view area was calculated as the number of coarse particles.

(4) Determination of filter pressure rise Polyester was extruded using a gear pump and a filter / attached 20 mmφ single-screw extrusion spinning machine, and the rise in pressure applied to the filter was measured. Filter the metal nonwoven type 20 [mu] m (Nasuron NF-08), filter diameter 16 mm (filtration area 2.01cm ^2), the discharge amount was 5 g / min. The pressure increase coefficient k per unit time was determined based on the following formula, and if k ≦ 5, it was determined that there was no practical problem.
k = ΔP (MPa / h) / (Q (kg / h) / S (cm ² ))
(ΔP is the pressure increase per hour (MPa), Q is the discharge rate per hour (kg / h), S is the area of the filter (cm ² ))
○: k ≦ 5
Δ: 5 <k ≦ 10
X: k> 10

(5) Foreign matter judgment of film The light of the fluorescent lamp was applied from the opposite direction of the sheet | seat which cut the film into 200 mm x 300 mm, and the number of the bright spots observed visually was measured as a foreign material. The total number of foreign matters was calculated for 10 sheets and determined based on the following criteria.
○: Number of foreign matter is 100 or less Δ: Number of foreign matter is 101 to 500 ×: Number of foreign matter is 501 or more

Example 1
(1) Preparation of polycondensation catalyst solution (preparation of aqueous solution of aluminum compound)
After adding 5.0 liters of pure water to a flask equipped with a cooling tube at room temperature and normal pressure, 200 g of basic aluminum acetate was added as a slurry with pure water while stirring at 200 rpm. Further, pure water was added so as to be 10.0 liters as a whole, and the mixture was stirred at room temperature and normal pressure for 12 hours. Thereafter, the jacket temperature was changed to 100.5 ° C., the temperature was raised, and the mixture was stirred under reflux for 3 hours from the time when the internal temperature reached 95 ° C. or higher. Stirring was stopped and the mixture was allowed to cool to room temperature to obtain an aqueous solution.
(Preparation of ethylene glycol mixed solution of aluminum compound)
After adding an equal volume of ethylene glycol to the aqueous aluminum compound solution obtained by the above method and stirring for 30 minutes at room temperature, the internal temperature is controlled to 80 to 90 ° C., and the pressure is gradually reduced to reach 27 hPa while stirring for several hours. Water was distilled off from the system to obtain an ethylene glycol solution of an aluminum compound at 20 g / l.
(Preparation of lithium glycol solution of lithium compound)
After 5.0 liters of ethylene glycol was added to the flask at room temperature and normal pressure, 200 g of lithium acetate dihydrate was added while stirring at 200 rpm. Further, ethylene glycol was added so that the whole became 10.0 liters, and the mixture was stirred at normal temperature and pressure for 12 hours to obtain an ethylene glycol solution of a lithium compound of 20 g / l.
(Preparation of ethylene glycol slurry of inorganic particles)
A dispersion tank equipped with a homogenizer was charged with 5 liters of ethylene glycol and 600 g of silica particles (manufactured by Fuji Silysia Chemical Co., Silicia 310) as inorganic particles, and stirred and dispersed at 8000 rpm for 2 hours to obtain a slurry of 120 g / l. The average particle diameter of silica in the ethylene glycol slurry of the obtained silica particles was 2.3 μm.

(2) Esterification reaction and polycondensation A high-speed stirrer is provided in the transfer line from the third esterification reaction tank to the first polycondensation reaction tank, comprising three continuous esterification reaction tanks and three polycondensation reaction tanks. 0.75 parts by mass of ethylene glycol with respect to 1 part by mass of high-purity terephthalic acid was continuously supplied to a slurry preparation tank. The prepared slurry is continuously supplied, the first esterification tank has a reaction temperature of 250 ° C. and 110 kPa, the second esterification reaction tank has 260 ° C. and 105 kPa, the third esterification reaction tank has 260 ° C. and 105 kPa, and the second ester A polyester oligomer was obtained by continuously adding 0.025 parts by mass of ethylene glycol to the chemical reaction tank. The average AVO of the oligomer at the outlet of the first esterification reaction tank was 1500 eq / ton. In addition, AVo and OHVo of the oligomer at the outlet of the third esterification reaction tank were 300 eq / ton and 1400 eq / ton on average, respectively. The oligomer is continuously transferred to a continuous polycondensation apparatus composed of three reaction vessels, and the ethylene glycol solution of the aluminum compound and the ethylene glycol solution of the lithium compound prepared by the above method in an in-line mixer installed in the transfer line. The ethylene glycol slurry of silica particles is stirred so that the aluminum component and the lithium atom and the SiO ₂ molecule are 0.015 mol%, 0.035 mol%, and 0.23% by weight, respectively, with respect to the acid component in the polyester. (Addition pattern A), the initial polycondensation reaction tank is 265 ° C. and 9 kPa, the medium polycondensation reaction tank is 265 to 268 ° C. and 0.7 kPa, and the final polycondensation reaction tank is 273. Polyester of IV0.620 was obtained by polycondensation at 13.3 Pa. The characteristic values of the obtained polyester are shown in Table 1. The content of silica particles in the obtained polyester was 0.20% by weight, and the number of coarse particles of 10 μm or more was 210 particles / mm ² . In this polymerization method, the polycondensation catalyst containing the aluminum compound and phosphorus compound of the present invention and inorganic particles are mixed and added to the polymerization system at the same time, which is the worst addition from the viewpoint of preventing aggregation at the time of conventionally known polyester polymerization. Although it was a method, the obtained polyester had little aggregation of inorganic particles.

(3) Formation of polyester film The obtained polyester chip was vacuum-dried at 135 ° C for 10 hours. The polyester chip was quantitatively supplied to a twin screw extruder, melt extruded into a sheet at 280 ° C., and rapidly cooled and solidified on a metal roll maintained at a surface temperature of 20 ° C. to obtain a cast film having a thickness of 1400 μm.

  Next, this cast film was heated to 100 ° C. with a heated roll group and an infrared heater, and then stretched 3.5 times in the longitudinal direction with a roll group having a peripheral speed difference to obtain a uniaxially oriented film. Subsequently, the film was stretched 4.0 times in the width direction at 120 ° C. with a tenter and heated with an infrared heater at 260 ° C. for 0.5 seconds, and further 3% at 200 ° C. for 23 seconds. The biaxially oriented polyester film having a thickness of 100 μm was obtained. The properties of the obtained film are shown in Table 1.

(Example 2)
In the polymerization method of Example 1, Example 1 was performed except that the addition amounts of the aluminum compound and the lithium compound were 0.005 mol% and 0.010 mol% as aluminum atoms and lithium atoms with respect to the acid component in the polyester. In the same manner as above, a polyester having an IV of 0.58 was obtained. The characteristic values of the obtained polyester are shown in Table 1. The content of silica particles in the obtained polyester was 0.20% by weight, and the number of coarse particles of 10 μm or more was 370 / mm ² . The obtained polyester chip was formed in the same manner as in Example 1 to obtain a polyester film. The properties of the obtained film are shown in Table 1.

(Example 3)
In the polymerization method of Example 1, Example 1 was performed except that the addition amounts of the aluminum compound and the lithium compound were 0.005 mol% and 0.100 mol% as aluminum atoms and lithium atoms with respect to the acid component in the polyester. In the same manner as above, a polyester having an IV of 0.62 was obtained. Table 1 shows the characteristic values of the obtained polyester. The content of silica particles in the obtained polyester was 0.20% by weight, and the number of coarse particles of 10 μm or more was 120 particles / mm ² . The obtained polyester chip was formed in the same manner as in Example 1 to obtain a polyester film. The properties of the obtained film are shown in Table 1.

Example 4
In the polymerization method of Example 1, Example 1 was performed except that the addition amounts of the aluminum compound and the lithium compound were 0.020 mol% and 0.010 mol% as aluminum atoms and lithium atoms with respect to the acid component in the polyester. In the same manner as above, a polyester having an IV of 0.63 was obtained. The characteristic values of the obtained polyester are shown in Table 1. The content of silica particles in the obtained polyester was 0.20% by weight, and the number of coarse particles of 10 μm or more was 450 particles / mm ² . The obtained polyester chip was formed in the same manner as in Example 1 to obtain a polyester film. The properties of the obtained film are shown in Table 1.

(Example 5)
In the polymerization method of Example 1, Example 1 was performed except that the addition amounts of the aluminum compound and the lithium compound were 0.020 mol% and 0.100 mol% as aluminum atoms and lithium atoms with respect to the acid component in the polyester. In the same manner as above, a polyester having an IV of 0.65 was obtained. The characteristic values of the obtained polyester are shown in Table 1. The content of silica particles in the obtained polyester was 0.20% by weight, and the number of coarse particles of 10 μm or more was 270 / mm ² . The obtained polyester chip was formed in the same manner as in Example 1 to obtain a polyester film. The properties of the obtained film are shown in Table 1.

(Example 6)
In the polymerization method of Example 1, a polyester having an IV of 0.63 was prepared in the same manner as in Example 1 except that the amount of silica particles added was 0.06% by weight as SiO ₂ molecules with respect to the acid component in the polyester. Obtained. The characteristic values of the obtained polyester are shown in Table 1. The content of silica particles in the obtained polyester was 0.05% by weight, and the number of coarse particles of 10 μm or more was 70 / mm ² . The obtained polyester chip was formed in the same manner as in Example 1 to obtain a polyester film. The properties of the obtained film are shown in Table 1.

(Example 7)
In the polymerization method of Example 1, a polyester having an IV of 0.61 was prepared in the same manner as in Example 1 except that the amount of silica particles added was 0.81% by weight as SiO ₂ molecules with respect to the acid component in the polyester. Obtained. The characteristic values of the obtained polyester are shown in Table 1. The content of the silica particles in the obtained polyester is 0.70 wt%, the number of the above coarse particles 10μm was 850 pieces / mm ^2. The obtained polyester chip was formed in the same manner as in Example 1 to obtain a polyester film. The properties of the obtained film are shown in Table 1.

(Example 8)
A polyester having an IV of 0.62 was obtained in the same manner as in Example 1, except that the average particle size of the silica particles was 0.7 μm in the polymerization method of Example 1. The characteristic values of the obtained polyester are shown in Table 1. The content of silica particles in the obtained polyester was 0.20% by weight, and the number of coarse particles of 10 μm or more was 120 particles / mm ² . The obtained polyester chip was formed in the same manner as in Example 1 to obtain a polyester film. The properties of the obtained film are shown in Table 1.

Example 9
A polyester having an IV of 0.62 was obtained in the same manner as in Example 1 except that in the polymerization method of Example 1, kaolin particles having an average particle diameter of 0.7 μm were used instead of silica particles. The characteristic values of the obtained polyester are shown in Table 1. The content of kaolin particles in the obtained polyester was 0.20% by weight, and the number of coarse particles of 10 μm or more was 430 / mm ² . The obtained polyester chip was formed in the same manner as in Example 1 to obtain a polyester film. The properties of the obtained film are shown in Table 1.

(Example 10)
A polyester having an IV of 0.62 was obtained in the same manner as in Example 1 except that in the polymerization method of Example 1, calcium carbonate particles having an average particle diameter of 1.0 μm were used instead of silica particles. The characteristic values of the obtained polyester are shown in Table 1. The content of calcium carbonate particles in the obtained polyester was 0.20% by weight, and the number of coarse particles of 10 μm or more was 260 particles / mm ² . The obtained polyester chip was formed in the same manner as in Example 1 to obtain a polyester film. The properties of the obtained film are shown in Table 1.

(Comparative Example 1)
In the polymerization method of Example 1, the ethylene glycol solution of the aluminum compound and the ethylene glycol solution of the lithium compound prepared by the method of Example 1 in the third esterification reaction tank were respectively an aluminum atom and an acid component in the polyester. After continuously adding 0.015 mol% and 0.035 mol% as lithium atoms, an ethylene glycol slurry of silica particles is added to the acid component in the polyester by an in-line mixer installed in a transfer line. A polyester having an IV of 0.620 was obtained in the same manner as in Example 1 except that it was continuously added while stirring with a stirring mixer so that the amount was 0.23% by weight (addition pattern B). The characteristic values of the obtained polyester are shown in Table 1. The content of silica particles in the obtained polyester was 0.20 wt%, the number of the above coarse particles 10μm was 1540 pieces / mm ^2. This polymerization method is a conventionally known addition method for preventing aggregation of inorganic particles, in which a polycondensation catalyst containing an aluminum compound and a lithium compound and inorganic particles are separately added to the polymerization system. Aggregation of inorganic particles was not at a satisfactory level. The obtained polyester chip was formed in the same manner as in Example 1 to obtain a polyester film. The properties of the obtained film are shown in Table 1.

(Comparative Example 2)
In the polymerization method of Example 1, the addition of an ethylene glycol solution of an aluminum compound and an ethylene glycol solution of a lithium compound was added simultaneously with high-purity terephthalic acid and ethylene glycol, followed by an esterification reaction, and an in-line installed in a transfer line Example 1 except that ethylene glycol slurry of silica particles was continuously added with stirring by a mixer of a stirring type so as to be 0.23% by weight with respect to the acid component in the polyester (addition pattern C). In the same manner as above, a polyester having an IV of 0.620 was obtained. The characteristic values of the obtained polyester are shown in Table 1. The content of silica particles in the obtained polyester was 0.20% by weight, and the number of coarse particles of 10 μm or more was 2540 / mm ² . This polymerization method was the best addition method for preventing agglomeration of inorganic particles known in the past, in which a polycondensation catalyst containing an aluminum compound and a lithium compound and inorganic particles are further separated and added to the polymerization system. Aggregation of the resulting polyester inorganic particles was not at a satisfactory level. The obtained polyester chip was formed in the same manner as in Example 1 to obtain a polyester film. The properties of the obtained film are shown in Table 1.

(Comparative Example 3)
In the polymerization method of Example 1, instead of the ethylene glycol solution of the aluminum compound and the ethylene glycol solution of the lithium compound, 0.020 mol% of the ethylene glycol solution of antimony trioxide as antimony metal with respect to the acid component in the polyester was used. A polyester having an IV of 0.620 was obtained in the same manner as in Example 1 except that it was continuously added while stirring with an agitator-type mixer simultaneously with the ethylene glycol slurry of silica particles (addition pattern A). The characteristic values of the obtained polyester are shown in Table 1. The content of silica particles in the obtained polyester was 0.20% by weight, and the number of coarse particles of 10 μm or more was 1980 particles / mm ² . This polymerization method is the worst addition method from the conventionally known method of preventing aggregation of inorganic particles, in which antimony trioxide, which is a polycondensation catalyst, and inorganic particles are mixed and added simultaneously to the polymerization system. Aggregation of inorganic particles of the obtained polyester was not satisfactory. The obtained polyester chip was formed in the same manner as in Example 1 to obtain a polyester film. The properties of the obtained film are shown in Table 1.

(Comparative Example 4)
In the polymerization method of Example 1, instead of the ethylene glycol solution of the aluminum compound and the ethylene glycol solution of the lithium compound, the ethylene glycol solution of antimony trioxide in the third esterification reaction tank was antimony to the acid component in the polyester. After continuously adding 0.020 mol% as a metal, the ethylene glycol slurry of silica particles is 0.23% by weight with respect to the acid component in the polyester using an in-line mixer installed in the transfer line. Thus, polyester of IV0.620 was obtained by the method similar to Example 1 except having added continuously (addition pattern B), stirring with a stirring mixer. The characteristic values of the obtained polyester are shown in Table 1. The content of silica particles in the obtained polyester was 0.20% by weight, and the number of coarse particles of 10 μm or more was 1230 / mm ² . In this polymerization method, antimony trioxide as a polycondensation catalyst and inorganic particles are separately added to the polymerization system, which is a conventionally known addition method for preventing the aggregation of inorganic particles. Although aggregation could be suppressed to some extent, it was not a satisfactory level. The obtained polyester chip was formed in the same manner as in Example 1 to obtain a polyester film. The properties of the obtained film are shown in Table 1.

(Comparative Example 5)
(Preparation of ethylene glycol solution of phosphorus compound)
Irganox 1425 (manufactured by Ciba Specialty Chemicals Co., Ltd.) as a phosphorus compound was added to a flask equipped with a nitrogen introduction tube and a cooling tube after adding 2.0 liters of ethylene glycol at normal temperature and pressure and stirring at 200 rpm in a nitrogen atmosphere. 200 g was added. Further, 2.0 liters of ethylene glycol was added, the temperature was raised by changing the jacket temperature setting to 196 ° C., and the mixture was stirred under reflux for 60 minutes from the time when the internal temperature reached 185 ° C. or higher. Thereafter, the heating was stopped, the solution was immediately removed from the heat source, and the solution was cooled to 120 ° C. or less within 30 minutes while maintaining the nitrogen atmosphere.
(Esterification reaction and polycondensation reaction)
In the polymerization method of Example 1, as the catalyst to be added to the in-line mixer installed in the transfer line, the ethylene glycol solution of the aluminum compound and the ethylene glycol solution of the phosphorus compound and the ethylene glycol slurry of the silica particles prepared by the above method were each polyester. aluminum and phosphorus atoms relative to the acid component in 0.015 mol% SiO ₂ molecules and 0.036 mol%, continuously added with stirring at a stirring type mixer so that 0.23 wt% The polyester was polymerized in the same manner as in Example 1 except for (Addition pattern A). The polyester obtained had an IV of 0.480, and film formation was impossible.

  The polyesters of Examples 1 to 10 in which an aluminum compound and a lithium compound were simultaneously added as a polycondensation catalyst were polymerized in an addition pattern that was considered to be the worst for preventing aggregation of inorganic particles according to conventional knowledge of preventing aggregation. Surprisingly, a polyester with little aggregation of inorganic particles was obtained, and when this was used, a polyester film with a low pressure of the filter and few defects of the film was obtained. In contrast, although the polyesters of Comparative Examples 1 and 2 were polymerized with the addition pattern according to the conventional knowledge of preventing aggregation, it was not possible to obtain a polyester with less aggregation of inorganic particles, and the pressure of the filter And a polyester film satisfying the number of defects of the film could not be obtained. The polyesters of Comparative Example 3 and Comparative Example 4 using antimony trioxide as the polycondensation catalyst were more suitable for the polyester of Comparative Example 3 to which the polycondensation catalyst and the inorganic particles were added at the same time, as in the conventional knowledge of preventing aggregation. There was more aggregation than the polyester of Comparative Example 4 in which the condensation catalyst and inorganic particles were added separately, and a polyester film that was satisfactory in terms of the pressure increase of the filter and the number of defects of the film could not be obtained. Since the polyester of Comparative Example 5 is different from the catalyst configuration of the present invention, it is considered that sufficient catalytic action was not obtained by the addition of inorganic particles.

The polyester of the present invention is produced using a novel catalyst having a component other than an antimony compound or a germanium compound as a main component and excellent in catalytic activity, and the dispersibility of the inorganic particles added during the production is good. The film using the polyester of the present invention has an effect of being excellent in running property, wearability, and optical properties. Therefore, the film using the polyester of the present invention is, for example, an antistatic film, an easily adhesive film, a card, a dummy can, an agricultural product, a building material, a cosmetic material, a wallpaper, an OHP film, and a printing For inkjet recording, sublimation transfer recording, laser beam printer recording, electrophotographic recording, thermal transfer recording, thermal transfer recording, printed circuit board wiring, membrane switch, near infrared absorption film for plasma display, touch panel and electro Transparent conductive film for luminescence, masking film, photoengraving, X-ray film, photographic negative film, retardation film, polarizing film, polarizing film protection (TAC), inspection of deflection plate and retardation plate Protective film and / or separator film, photosensitive resin film It can be used for field expansion film, diffusion sheets, reflection films, antireflection films, ultraviolet ray prevention, for example, for back grinding tape, a wide range of applications.

That is, the present invention
(1) Titanium dioxide, alumina, aluminosilicate, silicon dioxide, which is a polyester composition polymerized using a polycondensation catalyst containing an aluminum compound and a lithium compound, and having an average particle size of 0.5 to 3.0 μm , 0.02 to 2.0 % by weight of inert inorganic particles selected from calcium oxide, calcium carbonate, barium sulfate, talc, mica, kaolinite, and zeolite, and the number of coarse particles of 10 μm or more is 1000 / It is a polyester composition characterized by being ² mm or less,
(2) A polyester composition polymerized using a polycondensation catalyst containing an aluminum compound and a lithium compound, and the solution and the average particle size of the lithium compound are 0 when the esterification reaction is substantially completed. A slurry of inert inorganic particles selected from titanium dioxide, alumina, aluminosilicate, 5-3.0 μm, silicon dioxide, calcium oxide, calcium carbonate, barium sulfate, talc, mica, kaolinite, and zeolite is previously excluded from the system. 2. The polyester composition according to claim 1, wherein the mixed liquid is added to the reaction system, and then the polycondensation reaction is completed.

That is, the present invention
(1) Titanium dioxide, alumina, aluminosilicate, silicon dioxide, which is a polyester composition polymerized using a polycondensation catalyst containing an aluminum compound and a lithium compound, and having an average particle size of 0.5 to 3.0 μm Inactive inorganic particles selected from calcium oxide, calcium carbonate, barium sulfate, talc, mica, kaolinite, and zeolite are contained in an amount of 0.02 to 1.0 % by weight, and the number of coarse particles of 10 μm or more is 1000 / It is a polyester composition characterized by being ² mm or less,
(2) A polyester composition polymerized using a polycondensation catalyst containing an aluminum compound and a lithium compound, and the solution and the average particle size of the lithium compound are 0 when the esterification reaction is substantially completed. A slurry of inert inorganic particles selected from titanium dioxide, alumina, aluminosilicate, 5-3.0 μm, silicon dioxide, calcium oxide, calcium carbonate, barium sulfate, talc, mica, kaolinite, and zeolite is previously excluded from the system. 2. The polyester composition according to claim 1, wherein the mixed liquid is added to the reaction system, and then the polycondensation reaction is completed.

The average particle diameter referred to in the present invention, water or ethylene glycol as a medium, to use those obtained from the particle size distribution measured by Les Za light scattering method.

Claims (3)

0.01 to 1.0 weight of inert inorganic particles having a mean particle size of 0.5 to 3.0 μm, which is a polyester composition polymerized using a polycondensation catalyst containing an aluminum compound and a lithium compound %, And the number of coarse particles of 10 μm or more is 1000 / mm ² or less. A polyester composition polymerized using a polycondensation catalyst containing an aluminum compound and a lithium compound, wherein the solution of the lithium compound and the average particle size are 0.5 to The slurry according to claim 1, which is obtained by adding a mixed liquid in which a slurry of inert inorganic particles of 3.0 μm previously mixed outside the system is added to the reaction system, and then completing the polycondensation reaction. Polyester composition. The polyester film which uses the polyester composition of Claim 1 as a structural component.