KR20070012410A - Polyester resin, molded articles thereof, and process for production of the articles - Google Patents

Abstract

An aromatic polyester resin comprising as the main component repeating units derived from an aromatic dicarboxylic acid and a glycol, characterized by a variance ratio (Mw/Mn) of molecular weight distribution of 3.00 or above. This resin is improved in flow characteristics and therefore little generates aldehydes in molding. Further, the resin can give molded articles excellent in mechanical characteristics such as pressure resistance and permits efficient production of molded articles (particularly blow molded articles) excellent in dimensional stability under heat by high-speed molding with little molding strain. Additionally, the resin little stains a mold and is excellent in long-time continuous molding properties, and the stretched blow molded articles made from the resin is excellent in the retention of aroma and taste. ® KIPO & WIPO 2007

Description

Polyester resin, molded articles comprising the same, and a method for producing the polyester molded article {Polyester resin, molded articles, and process for production of the articles}

The present invention relates to a polyester resin suitably used as a raw material of a molded article such as a hollow molded article including a beverage bottle, a sheet-like article, a stretched film and the like, and a polyester molded article made thereof, in particular, such as acetaldehyde during molding. The production of aldehydes is suppressed, and the hollow molded article having excellent transparency, little variation in transparency, excellent pressure resistance, pressure resistance, and thermal dimensional stability, and transparency, activity, and dimensional stability after molding It relates to a polyester molded article such as excellent sheet-like article and stretched film and a method for producing a polyester molded article.

Polyester whose main repeating unit is ethylene terephthalate (hereinafter sometimes abbreviated as PET) is a container such as carbonated beverage, juice, mineral water, etc., due to its excellent transparency, mechanical strength, heat resistance, gas barrier properties, and the like. It is adopted as material, and the spread is really surprising. In these applications, although a bottle sterilized at a high temperature in a polyester bottle is heat-filled or sterilized at a high temperature after filling the beverage, a bottle made of a polyester shrinks and deforms at the time of such a heat-filling process. Becomes As a method of improving the heat resistance of a polyester bottle, a method has been proposed in which the bottle mouth portion is heat treated to increase the crystallinity or heat-set the stretched bottle. In particular, when the crystallization of the mouth portion is insufficient, or when the degree of variation in crystallinity is large, the sealability with the cap may deteriorate, and the contents may leak.

In the case of beverages requiring heat charging, such as fruit juices, oolong teas, mineral water, etc., a method of crystallizing by heat treatment of the preformed or molded bottle's mouth section (Japanese Patent Publication No. 55-79237, Japanese Patent Application Laid-Open No. 58-110221) is common. In this method, that is, a method of heat-treating the oral part and the shoulder to improve the heat resistance, the crystallization rate PET can be processed at a low temperature for a short time because the time and temperature of the crystallization treatment greatly affect the productivity. Is preferably. On the other hand, the body portion is required to be transparent even if the heat treatment during molding is performed so as not to deteriorate the color tone of the bottle contents, and the wording portion and the body portion need opposite characteristics.

Moreover, in order to improve the heat resistance of a bottle trunk | drum, the method of heat-processing by making temperature of a stretch blow mold into high temperature is employ | adopted (Japanese Patent Publication No. 59-6216). However, if a large number of bottle moldings are continued using the same mold by this method, the bottles obtained with long-term operation are whitened and transparency is lowered, so that only bottles having no product value can be obtained. This was found to be due to adhesion of PET-based deposits on the mold surface, resulting in mold contamination, and transfer of the mold contamination to the surface of the bottle. In particular, in recent years, the molding speed has increased along with the miniaturization of the bottle, and in terms of productivity, shortening of the heating time and mold contamination for crystallization of the oral cavity has become a bigger problem.

In addition, when PET is extruded into a sheet-like material and the container obtained by vacuum molding is filled with food, and the lid made of the same material is left, shrinkage occurs and the opening of the lid is deteriorated. If you leave the container for a long time, it will shrink and you will not be able to close the lid.

Several proposals have been made to solve this problem. For example, there are methods for adding inorganic nucleating agents such as kaolin and talc to polyethylene terephthalate, and methods for adding organic nucleating agents such as montan wax salts, but these methods have problems in practical use due to the generation of foreign matters and haze. have. In addition, there is a method of adding a treated polyester obtained by pulverizing a polyester molded product obtained by melt molding from the polyester to the raw material polyester, but this method requires an extra step called melt molding pulverization, and furthermore, There is a risk of incorporation of contaminants other than polyester, which is not a preferable method economically and quality. Moreover, although the method of inserting the heat resistant resin piece into the mouth part is proposed, the productivity of the bottle is bad and there is also a problem in recyclability. In addition, in the method of improving the above problems, a molded article having excellent transparency and heat resistance dimensional stability, particularly a small hollow molded article, can be efficiently produced by high-speed molding, and a polyester having excellent continuous formability for a long time with little contamination of the mold can be produced. Resin has been proposed, but the heat treatment time of the bottle mouth portion is a long problem.

 Moreover, polyester contains aldehydes, such as acetaldehyde (henceforth abbreviated as AA) which is a by-product. When the content of aldehydes in the polyester is large, the content of aldehydes in materials such as containers and other packaging molded from them also increases, affecting the flavor and smell of beverages filled in the containers and the like.

In recent years, polyester containers mainly made of polyethylene terephthalate have been used as containers for low flavor beverages such as mineral water and oolong tea. In the case of such beverages, these beverages are generally heated or sterilized by heating after filling, but the reduction of the acetaldehyde content of the beverage container is becoming increasingly important. For beverage cans, a method for producing cans using a metal plate coated with a polyester film whose main surface is ethylene terephthalate as the main repeating unit is adopted for the purpose of process simplification, hygiene and pollution prevention. It became. Also in this case, the contents are heated and sterilized at a high temperature after filling, but it has been found that using a film having a sufficiently low acetaldehyde content is an essential requirement for improving the flavor or smell of the contents.

For this reason, various measures have been conventionally adopted in order to reduce the acetaldehyde content in polyester. As these measures, for example, a method of lowering the oligomer and aldehyde by subjecting the polyester prepolymer obtained by melt polymerization under reduced pressure or under the flow of an inert gas to reduce the oligomer and aldehyde, the polyester prepolymer, the moisture content of 2000 ppm After adjusting the humidity to the above, the method of crystallization and solid-phase polymerization, the polyester particles are treated with hot water of 50-200 ° C., and then heat treated under reduced pressure or under inert gas flow. 8-120062), extraction and washing with water or an organic solvent before and after solid phase polymerization have been proposed. However, even in the molded article using the polyester obtained by these methods, the oligomer and acetaldehyde are not reduced to a problem-free level, and the problem has been solved in an unsolved state.

In addition, in recent years, thinning of bottles has been promoted and high molecular weight has been attempted to increase the strength of bottles. However, high molecular weight increases the melt viscosity during molding and increases the amount of acetaldehyde generated. Was occurring.

Moreover, the manufacturing method (for example, refer patent document 1) of the heat-resistant polyester container which processes the preform from two types of PET melt-mixing compositions from which an intrinsic viscosity differs 0.03 or more with the heat setting mold of specific temperature conditions, and obtained heat resistance Polyester container (Japanese Patent Publication No. 62-58973), a polyester having an extreme viscosity of 0.60 to 0.70 deciliters / gram, a specific elevated crystallization temperature and a crystallization temperature at a specific temperature drop, and 0.77 to 0.90 deciliters A method of producing a heat-resistant polyester container (e.g., see Patent Document 2) which draws and blows a preform from a mixture of polyesters having an extreme viscosity of gram / gram and a crystallization temperature at a specific elevated temperature and a crystallization temperature at a specific elevated temperature is proposed. However, these methods still have problems in obtaining molded articles having stable transparency and reduced acetaldehyde content. All.

In addition, a compound (see Patent Document 3, for example) of a solid-state polymerization PET and a copolymerized polyethylene terephthalate has been proposed, and by using this, the aldehyde content of the hollow molded body can be reduced, but a copolymerization component exists. For this reason, there is a problem in the heat resistance and the pressure resistance of the obtained molded product, which cannot be satisfied, and awaiting a solution.

Patent Document 1: Japanese Patent Publication No. 62-43851

Patent Document 2: Japanese Patent Application Laid-Open No. 10-287799

Patent Document 3: Japanese Patent Application Laid-Open No. 58-45254

Brief description of the drawings

1 is a plan view of an end-mounted molded plate.

2 is a side view of the end-mounted molded plate.

3 is a schematic view of the water treatment apparatus used in the embodiment.

Disclosure of the Invention

Problems to be Solved by the Invention

MEANS TO SOLVE THE PROBLEM This invention solves the problem with the said conventional method, suppresses generation | occurrence | production of aldehydes, such as acetaldehyde at the time of shaping | molding, and is excellent in transparency, little fluctuation of transparency, and a hollow molded article excellent in pressure resistance or heat resistance dimensional stability In particular, it is an object of the present invention to provide a polyester resin capable of efficiently producing a hollow molded article having excellent pressure resistance and heat resistance pressure resistance by high-speed molding, a polyester molded article comprising the same, and a manufacturing method thereof.

Means to solve the problem

MEANS TO SOLVE THE PROBLEM This inventor reached | attained this invention as a result of earnestly examining in order to achieve the said objective.

The present invention is as follows.

(1) A polyester resin comprising an aromatic dicarboxylic acid component and an aromatic polyester having a repeating unit comprising a glycol component, wherein the dispersion ratio Mw / Mn of the molecular weight distribution is 3.00 or more.

(2) A polyester resin comprising at least two kinds of polyesters having substantially the same composition as a main component, wherein the difference in the intrinsic viscosity of the polyester is in the range of 0.05 to 0.30 dl / g, The difference of crystallization temperature is less than 18 degreeC, The polyester resin characterized by the above-mentioned.

(3) A polyester resin containing the following polyesters A and B as main components of ethylene terephthalate as the main repeating unit, the difference between the intrinsic viscosity IV _A of polyester _A and the intrinsic viscosity IV _B of polyester B It is the range of 0.05-0.30, and the difference of the crystallization temperature at the time of temperature fall of polyester A, and the crystallization temperature at the time of temperature fall of polyester B is 18 degrees C or less, The polyester resin characterized by the above-mentioned.

Polyester A: The intrinsic viscosity IV _A is 0.60 to 0.75 dl / g, the acetaldehyde content is 10 ppm or less, the crystallization temperature at elevated temperature measured by DSC is 140 to 178 캜, and the crystallization temperature at elevated temperature is 160 to 190 캜. Polyester

Polyester B: The intrinsic viscosity IV _B is 0.73 to 0.90 dl / g, the acetaldehyde content is 10 ppm or less, the crystallization temperature at elevated temperature measured by DSC is 140 to 178 ° C, and the crystallization temperature at elevated temperature is 160 to 190 ° C. Polyester

(4) The polyester resin according to any one of (1) to (3), wherein the dispersion ratio Mz / Mn of the molecular weight distribution is 3.60 or more.

(5) The polyester resin according to any one of (1) to (4), wherein the cyclic trimer content is 0.50% by weight or less.

(6) The polyester resin according to any one of (1) to (5), wherein the cyclic ester oligomer increase amount at the time of melting at a temperature of 290 ° C. for 60 minutes is 0.50% by weight or less.

(7) The polyester resin in any one of (1)-(6) which contains 0.1-5000 ppm of fines of the polyester of the same composition as polyester.

(8) A polyester resin characterized by blending 0.1 ppb to 50000 ppm of at least one resin selected from the group consisting of a polyolefin resin and a polyacetal resin to the polyester resin of any one of (1) to (7). Composition.

(9) kneading the polyester resin according to any one of (1) to (8) under the condition that the melt resin temperature in the molding machine is 260 to 295 ° C and the melt residence time in the molding machine is 10 to 500 seconds; A method for producing a polyester unstretched molded body, characterized in that it is molded.

(10) A method for producing a polyester stretched molded article, wherein the polyester unstretched molded article obtained by the production method of (9) is stretched in at least one direction.

(11) The polyester molded object whose dispersion ratio Mw / Mn of molecular weight distribution is 3.00 or more.

(12) The polyester molded object whose dispersion ratio Mz / Mn of molecular weight distribution is 3.30 or more.

Effects of the Invention

The present invention is a polyester resin which gives a molded product having a low amount of aldehydes during molding and a molded article having excellent mechanical properties such as pressure resistance when the flowable properties are improved, and has a low distortion during molding and a heat resistance dimensional stability. This excellent molded article, particularly a hollow molded article, can be efficiently produced by high-speed molding, and a polyester-stretched hollow molded article having excellent long-term continuous moldability and less flavor retention can be produced. Grant.

Best Mode for Carrying Out the Invention

EMBODIMENT OF THE INVENTION Hereinafter, embodiment of the polyester resin of this invention, the polyester molded object which consists of it, and the manufacturing method of a polyester molded object is demonstrated concretely.

The polyester resin of this invention is an aromatic polyester which has a repeating unit which consists mainly of an aromatic dicarboxylic acid component and a glycol component, and is a polyester resin whose dispersion ratio Mw / Mn of the molecular weight distribution is 3.00 or more, and greatly increases molecular weight distribution. As a result, the melt viscosity of the polymer can be lowered and the molding can be carried out at a lower temperature forming temperature, and the resulting aldehydes such as acetaldehyde can be reduced, whereby a molded article having a smaller content of aldehydes can be obtained. . In addition, it is advantageous to obtain a bottle with further improved strength, and by using the polyester resin of the present invention, it is possible to easily form a thin bottle having no problem in terms of the strength of the bottle even if the thickness of the trunk portion is reduced.

In addition, since the molding temperature can be lowered for the same reason, it becomes possible to suppress the formation of the cyclic ester oligomer at the time of melt molding low, and in particular, the small hollow molded article can be efficiently produced by high-speed molding, Therefore, the polyester resin which is high in productivity and excellent in continuous moldability for a long time with little contamination of a metal mold | die can be provided. Moreover, it is also possible to provide the sheet-like thing excellent in the dimensional stability after shaping | molding.

The dispersion ratio Mw / Mn of the preferred molecular weight distribution of the aromatic polyester is 3.00 or more, more preferably 3.05 or more, most preferably 3.10 or more, and the dispersion ratio Mw / Mn of the molecular weight distribution is less than 3.00 to maintain transparency. In order to melt | dissolve at the time of shaping | molding, it is necessary to make higher, and aldehydes, such as acetaldehyde, of a molded object cannot be reduced. Moreover, there exists a tendency for a bottle's strength to fall.

Here, the dispersion ratios Mw / Mn and Mz / Mn of the molecular weight distribution are Mw / Mn and Mz / from the number average molecular weight (Mn), weight average molecular weight (Mw) and Z average molecular weight fraction (Mz) determined by the GPC method. It is the value calculated by Mn. Details are described in the section of measuring method 16 described later.

As a method of making the dispersion ratio Mw / Mn of the molecular weight distribution of an aromatic polyester resin into 3.00 or more, the method of blending two or more types of polymers of substantially the same composition with a different number average molecular weight, and the conditions at the time of polymerization (for example, In the case of a continuous polymerization apparatus, methods, such as lengthening of a residence time, adjustment of the number of polymerization tanks, etc.), etc. are mentioned, The method of blending two or more types of polymers which have a different molecular weight distribution is preferable. The blend may be a molten mixture or a dry blend.

Moreover, when the polyester resin of this invention is a polyester resin which contains at least two types of polyester of substantially the same composition as a main component, the difference of the intrinsic viscosity of the said polyester is the range of 0.05-0.30 dl / g, The difference of the crystallization temperature at the time of temperature-fall of polyester is less than 18 degreeC. The difference in intrinsic viscosity of the polyester is preferably 0.06 to 0.27 dl / g, more preferably 0.07 to 0.23 dl / g, particularly preferably 0.10 to 0.20 dl / g. When said intrinsic viscosity difference is less than 0.05 dl / g, content of aldehydes, such as acetaldehyde, of the obtained molded object cannot be reduced, and flavor retention cannot be improved. Moreover, when the said intrinsic viscosity difference exceeds 0.30 dl / g, a thickness nonuniformity, a whitened flow shape, etc. will arise in the obtained molded object, and will become a problem.

Here, when the polyester resin of this invention consists of two or more types of polyester, the difference of the said intrinsic viscosity means the difference of the intrinsic viscosity of a maximum polyester and a minimum polyester regarding an intrinsic viscosity. In addition, maximal polyester is polyester B and minimum polyester is polyester A with respect to an intrinsic viscosity below.

Polyesters having different intrinsic viscosities used in the present invention are polyesters prepared so that the difference of intrinsic viscosities falls within the scope of the present invention in the melt polycondensation reaction step or the solid-phase polymerization reaction step subsequent thereto, or the extreme viscosities thereof. A polyester treated with water under conditions that do not degrade.

As another production method for obtaining polyesters having different intrinsic viscosities, there is a method of heat-processing a polyester at water and high temperature to hydrolyze it, or a method of melt treatment with an extruder or the like. However, since the method by hydrolysis is carried out in the solid state, it is very difficult to manage the degree of IV degradation, and it is difficult to obtain polyester particles having a narrow IV fluctuation range, and the particles after the hydrolysis treatment are impacted during transportation. Since it is easy to generate fine powder by such a method, there arises a problem that the variation in the transparency and crystallization rate of the molded article when these are used becomes very large, and the transparency of the molded article and the variation thereof become large. In addition, the method by the melt treatment increases the aldehydes such as acetaldehyde at the time of treatment, there is a problem such as affecting the flavor retention or coloring. Therefore, the polyester of this invention does not include the polyester hydrolyzed by IV deterioration by methods, such as heat treatment under pressure with water, and the polyester reduced by IV by melt processing.

Further, the difference in crystallization temperature at the time of lowering of the polyester is preferably within 16 ° C, more preferably within 14 ° C, particularly preferably within 12 ° C. When the difference of the crystallization temperature at the time of temperature fall exceeds 18 degreeC, the transparency of the obtained molded object becomes very bad.

Moreover, in the polyester resin of this invention, the compounding ratio of polyester A and polyester B is 95/5-5/95 by weight ratio, Preferably it is 92/8-8/92, More preferably, it is 90/10- 10/90, outside this range is not preferable because the object of the present invention is not achieved.

The polyester resin of the present invention is a mixture of at least two kinds of polyesters each selected from the above-described polyesters A and B, and the composition of polyesters A and B is preferably substantially the same. It is preferable that 95 mol% or more of the acid component and glycol component in mutual composition are the same here, and it is preferable that 97 mol% or more, especially 98 mol% or more are the same that it is substantially the same here.

The difference between the intrinsic viscosity IV _A of polyester _A and the intrinsic viscosity IV _B of polyester B is preferably 0.06 to 0.27 dl / g, more preferably 0.07 to 0.23 dl / g, particularly preferably 0.10 to 0.20 dl / g g. When said intrinsic viscosity difference is less than 0.05 dl / g, content of aldehydes, such as acetaldehyde, of the obtained molded object cannot be reduced, and flavor retention cannot be improved. Moreover, when said intrinsic viscosity difference exceeds 0.30 dl / g, a thickness nonuniformity, whitening flow shape, etc. will arise in the obtained molded object, and will become a problem.

Moreover, the difference in crystallization temperature at the time of temperature-fall of polyester A and the crystallization temperature at the time of temperature-fall of polyester B becomes like this. Preferably it is within 16 degreeC, More preferably, it is within 14 degreeC, Especially preferably, it is within 12 degreeC. When the difference of the crystallization temperature at the time of temperature fall exceeds 18 degreeC, the transparency of the obtained molded object becomes very bad. In addition, the intrinsic viscosity of the polyester affects the crystallization temperature at the time of temperature drop, and the higher the viscosity, the lower the crystallization temperature at the time of temperature drop, so the practical difference of the crystallization temperature at the time of temperature drop is 2 ° C or more.

Intrinsic viscosity IV _A of the polyester A is preferably 0.62 ~ 0.74 ㎗ / g, more preferably 0.65 ~ 0.73 ㎗ / g, an acetaldehyde content is preferably 8 ppm or less, more preferably 5 ppm or less, and Preferably the crystallization temperature at the time of temperature rising is 145-177 degreeC, More preferably, it is 150-175 degreeC, The crystallization temperature at the time of temperature rising is preferably 162-185 degreeC, More preferably, it is 165-180 degreeC. If the polyester A having an intrinsic viscosity IV _A is less than 0.60 ㎗ / g it is poor in the transparency of the resulting molded article, or the problem that the mechanical strength of the molded article is lowered. If the content exceeds 0.75 dl / g, the effect of reducing aldehydes such as acetaldehyde is lowered. In addition, when the acetaldehyde content exceeds 10 ppm, the flavor retention of the obtained molded product is deteriorated, which is a problem. Moreover, when the crystallization temperature at the time of temperature rising of polyester A is less than 140 degreeC, transparency of a molded object will worsen, and when it exceeds 178 degreeC, the effect of improving the crystallization rate of a mouth part will worsen. When the crystallization temperature at the time of temperature-fall of polyester A is less than 160 degreeC, the effect of improving the crystallization rate of the oral part becomes worse, and when it exceeds 190 degreeC, transparency of a molded object worsens and it is a problem.

The intrinsic viscosity IV _B of polyester B is preferably 0.74 to 0.86 dl / g, more preferably 0.75 to 0.83 dl / g, and the acetaldehyde content is preferably 8 ppm or less, more preferably 5 ppm or less, further Preferably the crystallization temperature at the time of temperature rising is 145-177 degreeC, More preferably, it is 150-175 degreeC, The crystallization temperature at the time of temperature reduction is preferably 162-185 degreeC, More preferably, it is 165-180 degreeC. If a polyester B having an intrinsic viscosity IV _B of less than 0.73 ㎗ / g is bad in transparency of the resulting molded problem. On the other hand, when it exceeds 0.90 dl / g, the heat generation during molding becomes severe and the effect of reducing aldehydes such as acetaldehyde is lowered. In addition, when the acetaldehyde content exceeds 10 ppm, the flavor retention of the obtained molded article becomes poor, and on the other hand, in the economically balanced method, 1 ppm or less is the limit. Moreover, when the crystallization temperature at the time of temperature rising of polyester B is less than 140 degreeC, transparency of a molded object worsens, and when it exceeds 178 degreeC, the effect of improving the crystallization rate of a mouth part worsens, and it is a problem. When the crystallization temperature at the time of temperature-fall of polyester B is less than 160 degreeC, the effect of improving the crystallization rate of the oral part becomes worse, and when it exceeds 190 degreeC, transparency of a molded object worsens and it is a problem.

The polyester of the present invention is a thermoplastic polyester mainly obtained from an aromatic dicarboxylic acid component and a glycol component, preferably a polyester in which the aromatic dicarboxylic acid unit contains 70 mol% or more of the acid component, more preferably aromatic The polyester containing the dicarboxylic acid unit of 85 mol% or more of an acid component, Especially preferably, the aromatic dicarboxylic acid unit contains the polyester of 95 mol% or more of an acid component.

As an aromatic dicarboxylic acid component which comprises the polyester of this invention, terephthalic acid, 2, 6- naphthalenedicarboxylic acid, diphenyl-4,4'- dicarboxylic acid, diphenoxy ethane dicarboxylic acid, etc. And aromatic dicarboxylic acids and functional derivatives thereof.

 Moreover, as a glycol component which comprises the polyester of this invention, aliphatic glycols, such as ethylene glycol, 1, 3- trimethylene glycol, tetramethylene glycol, alicyclic glycol, such as cyclohexane dimethanol, etc. are mentioned. Can be.

As dicarboxylic acid as a copolymerization component used when the polyester of this invention is a copolymer, isophthalic acid, diphenyl-4,4'- dicarboxylic acid, diphenoxy ethanedicarboxylic acid, 4,4 ' Aromatic dicarboxylic acids such as -diphenyl ether dicarboxylic acid and 4,4'-diphenyl ketone dicarboxylic acid and functional derivatives thereof, oxy acids such as p-oxybenzoic acid and oxycaproic acid and functional derivatives thereof; Aliphatic dicarboxylic acids such as adipic acid, sebacic acid, succinic acid, glutaric acid, dimer acid and functional derivatives thereof, alicyclic dicarboxylic acids such as hexahydroterephthalic acid, hexahydroisophthalic acid and cyclohexanedicarboxylic acid; Functional derivatives thereof and the like.

As glycol as a copolymerization component used when the polyester of this invention is a copolymer, it is a diethylene glycol, 1, 3- trimethylene glycol, tetramethylene glycol, pentamethylene glycol, hexamethylene glycol, octamethylene glycol, decamethylene glycol, Aliphatic glycols such as 2-ethyl-2-butyl-1,3-propanediol, neopentyl glycol, dimer glycol, 1,2-cyclohexanediol, 1,4-cyclohexanediol, 1,1-cyclohexanedimethylol Alicyclic glycols such as 1,4-cyclohexanedimethylol, 2,5-norbornanedimethylol, xylylene glycol, 4,4'-dihydroxybiphenyl, 2,2-bis (4'- aromatic glycols such as β-hydroxyethoxyphenyl) propane, bis (4-hydroxyphenyl) sulfone, bis (4-β-hydroxyethoxyphenyl) sulfonic acid, and alkylene oxide adducts of bisphenol A, polyethylene glycol And polyalkylene glycols such as polybutylene glycol, and the like.

Moreover, as a polyfunctional compound as a copolymerization component used when the polyester of this invention is a copolymer, trimellitic acid, a pyromellitic acid, etc. are mentioned as an acid component, Glycerine and pentaerythritol are mentioned as a glycol component. The usage-amount of the above-mentioned copolymerization component should be a grade which keeps polyester substantially linear. Moreover, you may copolymerize a monofunctional compound, for example, benzoic acid, naphthoic acid, etc.

A preferred example of the polyester of the present invention is a polyester whose main structural unit is composed of ethylene terephthalate, more preferably 70 mol% or more of ethylene terephthalate units, and isophthalic acid, 1,4- as a copolymerization component. It is a copolyester containing cyclohexane dimethanol, etc., Especially preferably, it is a polyester containing 95 mol% or more of ethylene terephthalate units.

Examples of these polyesters include polyethylene terephthalate (hereinafter, abbreviated as PET), poly (ethylene terephthalate-ethylene isophthalate) copolymer, poly (ethylene terephthalate-1,4-cyclohexanedimethylene terephthalate) copolymer, Poly (ethylene terephthalate-dioxyethylene terephthalate) copolymer, poly (ethylene terephthalate-1,3-propylene terephthalate) copolymer, poly (ethylene terephthalate-ethylenecyclohexylenedicarboxylate) copolymer, etc. Can be mentioned.

Moreover, as another preferable example of the polyester of this invention, it is polyester which a main structural unit consists of 1, 3- propylene terephthalate, More preferably, it contains 70 mol% or more of 1, 3- propylene terephthalate units. It is polyester, and especially preferable is polyester which contains 95 mol% or more of 1, 3- propylene terephthalate units.

Examples of these polyesters include polypropylene terephthalate (PTT), poly (1,3-propylene terephthalate-1,3-propylene isophthalate) copolymer, poly (1,3-propylene terephthalate-1,4-cyclo Hexane dimethylene terephthalate) copolymer etc. are mentioned.

Moreover, as another preferable example of the polyester of this invention, the main structural unit is polyester comprised from butylene terephthalate, More preferably, it is co-polyester which contains 70 mol% or more of butylene terephthalate units, Especially Preferably it is polyester containing 95 mol% or more of butylene terephthalate units.

Examples of these polyesters include polybutylene terephthalate (PBT), poly (butylene terephthalate-butylene isophthalate) copolymer, poly (butylene terephthalate-1,4-cyclohexanedimethylene terephthalate) copolymer , Poly (butylene terephthalate-1,3-propylene terephthalate) copolymer, poly (butylene terephthalate-butylene cyclohexylene dicarboxylate) copolymer and the like.

Moreover, another preferable example of the polyester of this invention is the thermoplastic polyester whose main structural unit consists of ethylene-2,6-naphthalate, More preferably, 70 mol of ethylene-2,6-naphthalate units It is a thermoplastic polyester containing% or more, and especially preferable is a thermoplastic polyester containing 90 mol% or more of ethylene-2, 6- naphthalate units.

Examples of these thermoplastic polyesters include polyethylene-2,6-naphthalate (PEN), poly (ethylene-2,6-naphthalate-ethylene terephthalate) copolymer, poly (ethylene-2,6-naphthalate-ethyleneiso) Phthalate) copolymer, poly (ethylene-2, 6-naphthalate-dioxyethylene-2, 6-naphthalate) copolymer, etc. are mentioned.

Moreover, another preferable example of the polyester of this invention is polyester in which a main structural unit consists of 1, 4- cyclohexane dimethylene terephthalate, More preferably, a 1, 4- cyclohexane dimethylene terephthalate unit It is a copolyester containing 70 mol% or more, Especially preferably, it is a polyester containing 90 mol% or more of 1, 4- cyclohexane dimethylene terephthalate units.

Examples of these thermoplastic polyesters include poly-1,4-cyclohexanedimethylene terephthalate (PCT), poly (1,4-cyclohexanedimethylene terephthalate-ethylene terephthalate) copolymer, and the like.

The polyester of this invention can be manufactured basically by a conventionally well-known melt polycondensation method or melt polycondensation method-solid state polymerization method. The melt polycondensation reaction may be performed in one step or may be carried out in multiple stages. These may be comprised by the batch reaction apparatus, and may be comprised by the continuous reaction apparatus. The melt polycondensation step and the solid phase polymerization step may be operated continuously or may be operated separately. Although an example of the preferable continuous manufacturing method of the polyester of this invention is demonstrated to a polyethylene terephthalate (PET) as an example below, it is not limited to these. In other words, direct esterification is carried out by directly reacting terephthalic acid with ethylene glycol and other copolymerization components, if necessary, distilling off water, and then performing polycondensation under reduced pressure in the presence of a polycondensation catalyst, or dimethyl terephthalate and ethylene glycol. And transesterification while reacting other copolymerization components as necessary to distill off methyl alcohol, followed by a transesterification method in which polycondensation is carried out under reduced pressure in the presence of a polycondensation catalyst. Subsequently, in the case of increasing the intrinsic viscosity, or in the case of a low acetaldehyde content or a low cyclic trimer content such as an inner film of a low flavor beverage heat container or a metal can for beverage, the melt polycondensation obtained in this manner Polyester is subsequently solid-phase polymerized.

First, when preparing a low polymer by esterification, the slurry containing 1.02-1.5 mol, preferably 1.03-1.4 mol of ethylene glycol is adjusted with respect to 1 mol of terephthalic acid or its ester derivative, and this esterification is carried out. It is continuously supplied to the reaction process.

The esterification reaction is carried out while removing water or alcohol produced by the reaction from the rectification column out of the system under conditions under which ethylene glycol is refluxed using a multistage apparatus in which at least two esterification reactors are connected in series. The temperature of the esterification reaction of the 1st stage is 240-270 degreeC, Preferably it is 245-265 degreeC, and the pressure is 0.2-3 kg / cm <2> G, Preferably it is 0.5-2 kg / cm <2> G. The temperature of the last stage esterification reaction is 250-280 degreeC normally, Preferably it is 255-275 degreeC, and pressure is 0-1.5 kg / cm <2> G normally, Preferably it is 0-1.3 kg / cm <2> G. In the case of carrying out at three or more stages, the reaction conditions for the intermediate esterification reaction are conditions between the reaction conditions of the first stage and the reaction conditions of the final stage. It is preferable that the rise of the reaction rate of these esterification reactions is smoothly distributed in each step. Finally, the esterification reaction rate is preferably at least 90%, preferably at least 93%. By these esterification reaction, the lower order condensate of about 500-5000 molecular weight is obtained.

When terephthalic acid is used as a raw material, the said esterification reaction can be made to react also without a catalyst by catalysis as an acid of terephthalic acid, but you may carry out in the coexistence of a polycondensation catalyst.

In addition, tertiary amines such as triethylamine, tri-n-butylamine and benzyldimethylamine, quaternary ammonium hydroxides such as tetraethylammonium hydroxide, tetra-n-butylammonium hydroxide and trimethylbenzyl ammonium hydroxide and lithium carbonate When a small amount of a basic compound such as sodium carbonate, potassium carbonate, or sodium acetate is added, the ratio of the dioxyethylene terephthalate component unit in the main chain of polyethylene terephthalate is relatively low (5 mol% based on the total diol components). Since it can hold | maintain in the following), it is preferable.

Subsequently, when preparing a low polymer by transesterification, the solution containing 1.1-1.6 mol, preferably 1.2-1.5 mol of ethylene glycol is adjusted with respect to 1 mol of dimethyl terephthalates, and this is carried out to a transesterification process. Supply continuously.

The transesterification reaction is carried out while the methanol produced by the reaction is removed from the rectification column out of the system under conditions under which ethylene glycol is refluxed using a device in which one or two transesterification reactors are connected in series. The temperature of the transesterification reaction of the 1st stage is 180-250 degreeC, Preferably it is 200-240 degreeC. The temperature of the last stage transesterification reaction is usually 230 to 270 ° C, preferably 240 to 265 ° C, and a fatty acid salt such as Zn, Cd, Mg, Mn, Co, Ca, Ba, carbonate or Pb, as a transesterification catalyst. Zn, Sb, Ge oxide and the like are used. By these transesterification reaction, the lower order condensate of about 200-500 molecular weight is obtained.

As the above starting materials, dimethyl terephthalate, terephthalic acid or ethylene glycol is not only ethylene glycol derived from virgin dimethyl terephthalate, terephthalic acid or ethylene derived from paraxylene, but also methanol decomposition or ethylene glycol decomposition from used PET bottles. Recovered raw materials such as dimethyl terephthalate, terephthalic acid, bishydroxyethyl terephthalate or ethylene glycol recovered by the chemical recycle method can also be used as at least part of the starting raw materials. It goes without saying that the quality of the recovered raw material must be purified in terms of purity and quality depending on the intended use.

The resulting lower condensate is then fed to a multistage liquid condensation polymerization process. The polycondensation reaction conditions are the reaction temperature of the polycondensation of the first stage is 250 ~ 290 ℃, preferably 260 ~ 280 ℃, the pressure is 500 ~ 20 Torr, preferably 200 ~ 30 Torr, the polycondensation of the final stage The temperature of the reaction is 265 to 300 ° C, preferably 275 to 295 ° C, and the pressure is 10 to 0.1 Torr, preferably 5 to 0.5 Torr. In the case of carrying out at three or more stages, the reaction conditions for the intermediate condensation reaction are those between the reaction conditions of the first stage and the reaction conditions of the final stage. It is preferable that the degree of rise of the ultimate viscosity reached in each of these polycondensation reaction steps is smoothly distributed. In addition, you may use a 1-stage polycondensation apparatus for a polycondensation reaction.

The polycondensation reaction is carried out using a polycondensation catalyst. As the polycondensation catalyst, at least one compound selected from compounds of Ge, Sb, Ti, or Al is preferably used. These compounds are added to the reaction system as a powder, an aqueous solution, an ethylene glycol solution, a slurry of ethylene glycol, and the like.

As the Ge compound, amorphous germanium dioxide, crystalline germanium dioxide powder or slurry of ethylene glycol, a solution in which crystalline germanium is heated and dissolved in water, or a solution in which ethylene glycol is added and heat-treated are used. In order to obtain the polyester used by this invention, it is preferable to use the solution which heat-dissolved germanium dioxide in water, or the solution which added and heated ethylene glycol to this. In addition, compounds such as germanium tetraoxide, germanium hydroxide, germanium oxalate, germanium chloride, germanium tetraethoxide, germanium tetra-n-butoxide and germanium phosphite can also be used. These polycondensation catalysts can be added during the esterification process. When using a Ge compound, the usage-amount is 10-150 ppm, As for Ge residual amount in polyester, More preferably, it is 13-100 ppm, More preferably, it is 15-70 ppm.

Examples of the Ti compound include tetraalkyl titanates such as tetraethyl titanate, tetraisopropyl titanate, tetra-n-propyl titanate and tetra-n-butyl titanate and their partial hydrolysates, titanium acetate, titanium oxalate and oxalic acid. Titanium oxalate compounds such as titanyl ammonium, titanium oxalate sodium, potassium oxalate, potassium oxalate, calcium oxalate, titanium oxalate, titanium oxalate, trimellitic acid, titanium sulfate, titanium chloride, hydrolysates of titanium halides, titanium bromide Titanium complex with titanium fluoride, potassium hexafluoride, ammonium hexafluoride, ammonium hexafluoride, cobalt hexafluorotitanate, manganese hexafluoride, titanium acetylacetonate, hydroxy polyhydric carboxylic acid or nitrogen-containing polyhydric carboxylic acid Complex oxides consisting of water, titanium and silicon or zirconium, and reactants of titanium alkoxides and phosphorus compounds. Can be. A Ti compound is added so that it may become 0.1-50 ppm of range as Ti residual amount in a produced polymer.

Examples of the Sb compound include antimony trioxide, antimony acetate, antimony tartarate, potassium antimony tartarate, antimony oxychloride, antimony glycolate, antimony pentoxide, triphenyl antimony and the like. The Sb compound is added so as to remain in the range of 50 to 250 ppm as the amount of Sb remaining in the resulting polymer.

As the Al compound, inorganic acid salts such as aluminum acetate, basic aluminum acetate, aluminum chloride, aluminum hydroxide, aluminum hydroxide chloride, aluminum carbonate, aluminum phosphate, aluminum phosphonate, aluminum n-propoxide, aluminum iso-propoxide, aluminum n Aluminum chelate compounds such as butoxide, aluminum t-butoxide, aluminum alkoxide, aluminum acetylacetonate, aluminum acetyl acetate, aluminum ethyl acetate acetate, aluminum ethyl acetate acetate di iso-propoxide, trimethylaluminum and triethyl Organoaluminum compounds such as aluminum, partial hydrolyzates thereof, aluminum oxide and the like. Of these, aluminum acetate, basic aluminum acetate, aluminum chloride, aluminum hydroxide, aluminum hydroxide chloride and aluminum acetylacetonate are particularly preferred. Al compound is added so that it may become a range of 5-200 ppm as Al residual amount in a produced polymer.

In addition, in manufacture of the polyester of this invention, you may use an alkali metal compound or an alkaline earth metal compound together as needed. As an alkali metal and alkaline earth metal, it is preferable that it is at least 1 sort (s) chosen from Li, Na, K, Rb, Cs, Be, Mg, Ca, Sr, Ba, and the use of an alkali metal or its compound is more preferable. When using an alkali metal or its compound, especially use of Li, Na, K is preferable. As a compound of an alkali metal or an alkaline earth metal, For example, saturated aliphatic carboxylic acid salts, such as formic acid, acetic acid, propionic acid, butyric acid, and oxalic acid, unsaturated aliphatic carboxylic acid salts, such as acrylic acid and methacrylic acid, benzoic acid, etc. Halogen-containing carboxylates, such as aromatic carboxylates and trichloroacetic acid, hydroxycarboxylates, such as lactic acid, citric acid, and salicylic acid, carbonic acid, sulfuric acid, nitric acid, phosphoric acid, phosphonic acid, hydrogen carbonate, hydrogen phosphate, hydrogen sulfide , Inorganic sulfates such as sulfurous acid, thiosulfate, hydrochloric acid, hydrobromic acid, chloric acid and bromic acid, organic sulfonic acid salts such as 1-propanesulfonic acid, 1-pentanesulfonic acid and naphthalenesulfonic acid, organic sulfates such as lauryl sulfate, Alkoxides such as oxy, ethoxy, n-propoxy, iso-propoxy, n-butoxy, tert-butoxy, chelate compounds with acetylacetonate, etc., hydrides, oxides, hydroxides, etc. Can be mentioned.

The alkali metal compound or alkaline earth metal compound is added to the reaction system as a powder, an aqueous solution, an ethylene glycol solution, or the like. The alkali metal compound or alkaline earth metal compound is added so as to remain in the range of 1 to 50 ppm as the remaining amount of these elements in the produced polymer.

In addition, the polyester of the present invention is a group consisting of silicon, manganese, iron, cobalt, zinc, gallium, strontium, zirconium, niobium, molybdenum, indium, tin, hafnium, thallium, tungsten You may contain the metal compound containing at least 1 type of element chosen from. Examples of these metal compounds include saturated aliphatic carboxylates such as acetates of these elements, unsaturated aliphatic carboxylates such as acrylates, aromatic carboxylates such as benzoic acid, and halogen-containing carboxylates such as trichloroacetic acid, and hydroxides such as lactates. Inorganic salts such as oxycarboxylates and carbonates, organic sulfonates such as 1-propanesulfonic acid salts, organic sulfates such as lauryl sulfate, and chelate compounds with oxides, hydroxides, chlorides, alkoxides, acetylacetonates, and the like. It is added to the reaction system as a powder, an aqueous solution, an ethylene glycol solution, a slurry of ethylene glycol, or the like. These metal compounds are added so as to remain in the range of 0.05 to 3.0 mol as the residual amount of the elements of these metal compounds per ton of the produced polymer. These metal compounds can be added at any stage of the polyester production reaction step.

Moreover, from the group which consists of phosphoric acid esters, such as phosphoric acid, polyphosphoric acid, and trimethyl phosphate, a phosphonic acid type compound, a phosphinic acid type compound, a phosphine oxide type compound, an aphosphonic acid type compound, an aphosphinic acid type compound, and a phosphine type compound as a stabilizer, It is preferable to use at least 1 type of phosphorus compound selected. Specific examples include phosphoric acid, trimethyl phosphate, triethyl phosphate, tributyl phosphate, triphenyl phosphate, monomethyl phosphate, dimethyl phosphate, monobutyl phosphate, dibutyl phosphate, phosphorous acid, trimethyl phosphate, and phosphorous acid Ethyl ester, phosphorous acid tributyl ester, methyl phosphonic acid, methyl phosphonic acid dimethyl ester, ethyl phosphonic acid dimethyl ester, phenyl phosphonic acid dimethyl ester, phenyl phosphonic acid diethyl ester, phenyl phosphonic acid diphenyl ester and the like. These stabilizers can be added during the esterification step from a slurry mixing bath of terephthalic acid and ethylene glycol. P compound is added as P residual amount in the produced polymer, Preferably it is in the range of 5-100 ppm. When using an Al compound as a polycondensation catalyst, it is preferable to use together with a phosphorus compound, and it is preferable to use as a solution or slurry which the aluminum compound and the phosphorus compound previously mixed in the solvent. In the case of an Al compound, a more preferable phosphorus compound is at least one selected from the group consisting of a phosphonic acid compound, a phosphinic acid compound, a phosphine oxide compound, an aphosphonic acid compound, an aphosphinic acid compound, and a phosphine compound It is a phosphorus compound. By using these phosphorus compounds, the effect of improving the catalytic activity is seen, and the physical properties such as thermal stability of the polyester are also improved. Among these, when a phosphonic acid type compound is used, the improvement of a physical property and the effect of a catalyst activity are large, and it is preferable. Among the above-mentioned phosphorus compounds, the use of a compound having an aromatic ring structure is preferred because it is effective in improving physical properties and improving catalytic activity.

The melt polycondensation polyester obtained as described above is, for example, a method in which the melt polyester is extruded into water from the die pore after the end of the melt polycondensation and cut in water, or the die pore after the end of the melt polycondensation. After extruded into the strand form from air into chips, it is chipped into a columnar shape, a spherical shape, a square shape, or a plate shape by a method of chipping while cooling with cooling water.

Moreover, as cooling water at the time of chipping of said melt polycondensation polyester, it is preferable to use the cooling water which satisfy | fills at least one of following (1)-(4), Furthermore, all (1)-(4) It is most preferable to use water that satisfies.

Na ≤ 1.0 (ppm) (1)

Mg ≤ 1.0 (ppm) (2)

Si ≤ 2.0 (ppm) (3)

Ca ≤ 1.0 (ppm) (4)

The sodium content Na in the cooling water is preferably Na ≦ 0.5 ppm, more preferably Na ≦ 0.1 ppm. The magnesium content (Mg) in the cooling water is preferably Mg≤0.5 ppm, more preferably Mg≤0.1 ppm. In addition, the content (Si) of silicon in the cooling water is preferably Si ≦ 0.5 ppm, more preferably Si ≦ 0.3 ppm. Moreover, the calcium content (Ca) in the cooling water is preferably Ca≤0.5 ppm, more preferably Ca≤0.1 ppm.

In order to reduce sodium, magnesium, calcium, and silicon of the cooling water, an apparatus for removing sodium, magnesium, calcium, and silicon is provided in at least one of the steps until the industrial water is sent to the chip cooling process. In addition, a filter is provided to remove clay minerals such as silicon dioxide and aluminosilicate that have become particulates. Examples of the device for removing sodium, magnesium, calcium, and silicon include an ion exchange device, an ultrafiltration device, a reverse osmosis membrane device, and the like.

Subsequently, it is preferable that the above-mentioned melt polycondensation polyester chip is precrystallized by a continuous crystallizer of two or more stages in an unstable gas atmosphere. For example, in the case of PET, in the first stage of precrystallization, at a temperature of 100 to 180 ° C for 1 minute to 5 hours, then in the second stage of precrystallization, at a temperature of 160 to 210 ° C for 1 minute to 3 hours Under conditions, in the second stage or more of preliminary crystallization, it is preferable to sequentially crystallize step by step under conditions of 1 minute to 3 hours at a temperature of 180 to 210 ° C. The crystallinity of the chip after crystallization is in the range of 30 to 65%, preferably 35 to 63%, more preferably 40 to 60%. In addition, the crystallinity can be obtained from the density of the chip.

Subsequently, solid phase polymerization is carried out at an optimum temperature for the prepolymer under an inert gas atmosphere or reduced pressure so that the increase in the ultimate viscosity due to solid phase polymerization is 0.10 dl / g or more. For example, in the case of PET, the upper limit of the solid phase polymerization is preferably 215 ° C or lower, further preferably 210 ° C or lower, particularly 208 ° C, and the lower limit is 190 ° C or higher, preferably 195 ° C. That's it.

After completion of the solid phase polymerization, the chip temperature is preferably about 70 ° C. or less, preferably 60 ° C. or less, and more preferably 50 ° C. or less within about 30 minutes, preferably within 20 minutes, more preferably within 10 minutes. Do.

In the case where the polyester of the present invention is a polyester whose main repeating unit is ethylene-2,6-naphthalate (hereinafter sometimes abbreviated as PEN), the intrinsic viscosity of at least two kinds of polyester is , 0.40 to 0.80 dl / g, preferably 0.42 to 0.75 dl / g, more preferably 0.45 to 0.70 dl / g. If IV is less than 0.40 dl / g, the mechanical properties of the obtained molded article and the like are bad. In addition, when it exceeds 0.80 dl / g, since it is necessary to increase the resin temperature at the time of melting by a molding machine or the like, it is accompanied by pyrolysis, resulting in an increase in aldehydes such as acetaldehyde, and the molded body being colored in yellow. A problem arises.

In the case where the polyester of the present invention is PEN, the following polyester C and polyester D are included as main components, and the difference between the crystallization temperature at the time of temperature reduction of polyester C and the crystallization temperature at the time of temperature reduction of polyester D is 18. It is preferable that it is a polyester resin within ° C.

Polyester C: Polyester whose intrinsic viscosity IV _A is 0.40-0.70 dl / g, the crystallization temperature at the time of temperature rising by DSC is 180-235 degreeC, and the crystallization temperature at the time of temperature fall is 160-210 degreeC.

Polyester D: Polyester whose intrinsic viscosity IV _B is 0.50 to 0.80 dl / g, the crystallization temperature at the time of temperature rising by DSC is 180-235 degreeC, and the crystallization temperature at the time of temperature fall is 160-210 degreeC.

When the polyester of the present invention is a polyester whose main structural unit is 1,3-propylene terephthalate, the intrinsic viscosity of at least two kinds of polyesters is 0.50 to 1.00 dl / g, preferably 0.55. It is selected within the scope of the invention from polyesters in the range of 0.90 dL / g, more preferably 0.60 0.85 dL / g. If the intrinsic viscosity is less than 0.50 dl / g, the mechanical properties of the obtained molded article deteriorate, which is a problem. In addition, the upper limit value of the intrinsic viscosity is 1.00 dl / g, and when it exceeds this, the resin temperature at the time of molding becomes high and thermal decomposition increases, the molecular weight decreases, the generation of aldehydes becomes severe, and yellowing is carried out. Problems occur.

When the polyester resin of this invention has at least two types of polyester as a main component as mentioned above, it can manufacture by controlling suitably the kind and addition amount of said polycondensation catalyst, melt polycondensation, solid-state polymerization conditions, etc. . Moreover, it can also be obtained by the method of impacting the polyester chip obtained in this way, and the method of mix | blending a polyolefin resin, especially polyethylene, a polyamide resin, a polyoxymethylene resin, etc. as demonstrated below.

The ratio of the terminal carboxyl group to the total number of terminal groups of the at least one polyester constituting the polyester resin of the present invention is 5 to 30 equivalent%, preferably 8 to 28 equivalent%, more preferably 9 to 26 It is preferable that it is equivalent%, Especially preferably, it is 10-25 equivalent%. If the ratio of the terminal carboxyl group to the total number of terminal groups is less than 5 equivalent%, the solid phase polymerization time during the preparation of such polyester becomes extremely long, and the economy becomes a problem, and moreover, acetaldehyde and the like during molding The generation of aldehydes is a problem. When the ratio of the terminal carboxyl group to the total number of terminal groups exceeds 30 equivalent%, the transesterification reaction between the two kinds of polyesters is promoted, resulting in rearrangement of the molecular weight distribution. The improvement effect is estimated to disappear.

Moreover, the dialkylene glycol content copolymerized in the polyester of this invention is 0.5-7.0 mol%, Preferably it is 1.0-6.0 mol%, More preferably, 1.5-5.0 mol% of the glycol component which comprises the said polyester. More preferably, it is 1.5-4.0 mol%. When the amount of dialkylene glycol exceeds 7.0 mol%, thermal stability becomes worse, molecular weight fall at the time of shaping | molding becomes large, and the amount of increase of content of aldehydes becomes large, and it is unpreferable. Moreover, in order to manufacture polyester with dialkylene glycol content less than 0.5 mol%, it is necessary to select uneconomical manufacturing conditions as transesterification conditions, esterification conditions, or polymerization conditions, and it does not fit in cost. Here, the dialkylene glycol copolymerized in polyester means, for example, in the case of the polyester whose main structural unit is ethylene terephthalate, diethylene glycol by-produced at the time of manufacture from ethylene glycol which is glycol ("DEG" hereafter). In the case of polyesters having 1,3-propylene terephthalate as the main structural unit, diethylene glycol copolymerized to the above polyester may be used. In di (1,3-propylene glycol) (or bis (3-hydroxypropyl) ether) produced by-product, di (1,3-propylene glycol (hereinafter sometimes referred to as DPG)) copolymerized with the polyester. Say

In particular, the amount of diethylene glycol copolymerized to the polyester whose main repeating unit consists of ethylene terephthalate is 1.0 to 5.0 mol%, preferably 1.3 to 4.5 mol%, more preferably of the glycol component constituting the polyester. Is 1.5 to 4.0 mol%. When the amount of diethylene glycol exceeds 5.0 mol%, thermal stability becomes worse, molecular weight fall at the time of shaping | molding becomes large, and the amount of increase of ataldehyde content and formaldehyde content becomes large, and it is unpreferable. Moreover, when diethylene glycol content is less than 1.0 mol%, transparency of the obtained molded object worsens.

Diethylene glycol and triethylene glycol (hereinafter sometimes referred to as "TEG") are partially by-produced from ethylene glycol during the polymerization reaction, so that a predetermined amount of DEG and / or TEG and its ester-forming derivatives is polymerized. Besides using it as a raw material, content of DEG component and / or TEG component can be controlled only by selecting reaction conditions, an additive, etc. suitably. As the additive, quaternary ammonium hydroxides such as tertiary amines such as triethylamine, tri-n-butylamine, and benzyldimethylamine, tetraethylammonium hydroxide, tetrabutylammonium hydroxide and trimethylbenzyl ammonium hydroxide And small amounts of basic compounds such as lithium carbonate, sodium carbonate, potassium carbonate and sodium acetate can be added to suppress the production of DEG and / or TEG. On the other hand, when a small amount of inorganic acids such as sulfuric acid is added to the polymerization raw material, it is also possible to promote the production of DEG and / or TEG and increase the content. The additive which controls the generation amount of these DEGs and / or TEGs may be used in the range of 0.001 to 10% by weight, preferably 0.005 to 1% by weight of all the polymerization raw materials, if necessary.

Moreover, content of aldehydes, such as acetaldehyde, of the polyester resin of this invention is 50 ppm or less, Preferably it is 30 ppm or less, More preferably, it is 10 ppm or less. When the aldehyde content exceeds 50 ppm, the effect of flavor retention of contents such as a molded article molded from such polyester is worsened. Moreover, it is preferable that these minimums are 0.1 ppb from a manufacturing problem. Herein, aldehydes are acetaldehyde in the case of polyester in which polyester is ethylene terephthalate as the main structural unit or polyester in which ethylene naphthalate is the structural unit, and 1,3-propylene terephthalate is the main structural unit. In the case of polyester to be mentioned, it is allyl aldehyde.

In particular, when the polyester resin of the present invention is composed of polyester having ethylene terephthalate as the main repeating unit, and this is used as a material for a low flavor beverage container such as mineral water, the polyester resin of the present invention The acetaldehyde content is preferably 10 ppm or less, preferably 6 ppm or less, more preferably 5 ppm or less, and most preferably 4 ppm or less. When the acetaldehyde content exceeds 10 ppm, the product value is deteriorated due to adverse effects on the smell, taste, and the like of the contents of the molded article formed from the polyester resin.

Further, the free ethylene glycol content and the free diethylene glycol content of the polyester resin are 30 ppm or less and 10 ppm or less, respectively, preferably 20 ppm or less and 7 ppm or less, more preferably 15 ppm or less and 5 It is preferable that it is ppm or less. When free ethylene glycol content exceeds 30 ppm, or when free diethylene glycol content exceeds 10 ppm, the free ethylene glycol content of the obtained polyester molded object exceeds 50 ppm, or free diethylene glycol content Since this exceeds 20 ppm, the flavor retention of the stretched blow molded body is deteriorated, which is a problem. In addition, the lower limit of free ethylene glycol content and free diethylene glycol content of a polyester resin is 5 ppm and 1 ppm from an economical viewpoint, respectively.

The content of the cyclic ester oligomer of the polyester resin of the present invention is 70% or less, preferably 60% or less, more preferably 50% or less of the cyclic ester oligomer content of the melt polycondensation polyester prepolymer of the polyester. It is preferable that it is% or less, Especially preferably, it is 35% or less. Here, although polyester generally contains the cyclic ester oligomer of various polymerization degrees, the cyclic ester oligomer used in this invention means the cyclic ester oligomer which has the highest content among the cyclic ester oligomer which polyester contains, and is an example. For example, in the case of polyester which has ethylene terephthalate as a main repeating unit, it refers to a cyclic trimer. In the case of PET in which the polyester is a representative of polyester having ethylene terephthalate as the main structural unit, the content of the cyclic trimer of the melt polycondensation polyester prepolymer is about 1.0% by weight, so that the polyester resin of the present invention It is preferable that content of a cyclic trimer is 0.70 weight% or less, Preferably it is 0.60 weight% or less, More preferably, it is 0.50 weight% or less, Especially preferably, it is 0.35 weight% or less. The lower limit of the cyclic trimer content is 0.20% by weight or more, preferably 0.22% by weight or more, and more preferably 0.25% by weight or more in terms of economical production. When the content of the cyclic trimer is 0.70% by weight or more, the oligomer adhesion to the gas exhaust port of the unstretched molded metal mold or the surface of the heat-setting mold after stretch molding increases rapidly, and the transparency of the obtained hollow molded body is very deteriorated.

Moreover, when the polyester resin of this invention is polyester which uses ethylene terephthalate as a main repeating unit, and is used for shaping | molding a highly heat-resistant hollow molded object, it heat-processes in a heating mold, but content of a cyclic trimer Silver is preferably 0.50% by weight or less, preferably 0.40% by weight or less, more preferably 0.35% by weight or less.

It is preferable that the fine content of the polyester resin of this invention is 0.1-5000 ppm. The content of pine is preferably 0.1 to 3000 ppm, more preferably 0.1 to 1000 ppm, still more preferably 0.1 to 500 ppm, and most preferably 0.1 to 100 ppm. When the compounding amount is less than 0.1 ppm, the crystallization rate is very slow, the crystallization of the oral part of the hollow molded container is insufficient, and therefore the shrinkage of the oral part is not within the range of the prescribed value, and the capping becomes impossible, and the heat-resistant hollow Contamination of the stretch heat setting mold for molding the molding container is severe, and in order to obtain a transparent hollow molding container, the mold should be frequently cleaned. Moreover, when exceeding 5000 ppm, the crystallization rate becomes faster than necessary, and the fluctuation | variation of the rate also becomes large. Therefore, in the case of a sheet-like thing, transparency and surface state worsen, and when this is extended, thickness nonuniformity worsens. In addition, the crystallinity of the oral cavity of the hollow molded body is excessive and the fluctuation becomes large. As a result, the shrinkage of the oral cavity does not fall within the prescribed range, resulting in poor capping of the oral cavity and leaking of the contents. As a result, normal stretching is impossible. In particular, the fine content of the polyester resin for hollow moldings is preferably 0.1 to 500 ppm. Moreover, it is preferable that the difference of melting | fusing point of the fine melting | fusing point and polyester chip which are contained in the polyester of this invention is 15 degrees C or less, Preferably it is 10 degrees C or less, More preferably, it is 5 degrees C or less. In the case where the difference includes fines exceeding 15 ° C, the crystals do not melt completely under the melt molding conditions normally used, and remain as crystal nuclei. For this reason, in the case of a hollow molded object, since the crystallization rate becomes high at the time of heating a hollow molded object oral part, the crystallization of an oral part becomes excessive. In addition, the unstretched molded article for blow molding is whitened, and thus, normal stretching is impossible, thickness irregularity occurs, and the crystallization rate is high, resulting in poor transparency of the obtained hollow molded article, and also increased variation in transparency.

However, when it is desired to obtain an unstretched molded article or a sheet-like article for blow molding having good transparency and stretchability from a polyester resin containing fine grain having a difference in melting point of the fine and the melting point of the chip exceeding 15 ° C, the melting point of the polyester chip It must be melt-molded at a temperature higher than about 40-50 degreeC. By the way, at such a high temperature, thermal decomposition of polyester becomes severe, and by-products, such as acetaldehyde and formaldehyde, generate | occur | produce in large quantities, and it has a big influence on the flavor of the contents, such as a molded object obtained as a result. In addition, when the polyester resin of this invention contains at least 1 sort (s) of resin chosen from the group which consists of the following polyolefin resin, polyamide resin, and polyacetal resin, these resin is generally polyester of this invention. Since thermal stability is inferior in many cases, in forming at such a high temperature, thermal decomposition is generated and a large amount of by-products are generated, and therefore, a great influence is caused by the flavor of the contents of the obtained molded body or the like.

In the case where the polyester resin of the present invention is PET, a fine or film-like article having a melting point exceeding 265 ° C becomes a problem.

The melting point of the fine is measured by the following method using a differential scanning calorimeter (DSC), but the melting peak temperature indicating the melting point of the fine is composed of one or more plural melting peaks, and in the present invention, the melting peak Is the peak temperature, and when there are a plurality of melting peaks, among these plurality of melting peaks, the melting peak temperature on the hottest side is referred to as the "peak temperature on the hottest side of the fine melting peak temperature". In the examples, the melting point is referred to as "fine melting point".

The amount of increase of the cyclic trimer when the polyester resin of the present invention is melted at a temperature of 290 ° C. for 60 minutes is 0.5% by weight or less, preferably 0.3% by weight or less, and more preferably 0.1% by weight or less. Do. When the amount of increase of the cyclic trimer when molten for 60 minutes at the temperature of 290 degreeC exceeds 0.50 weight%, the cyclic trimer will increase at the time of melting the resin of shaping | molding, and the oligomer adhesion to the heating die surface will increase rapidly and it will be obtained. Transparency, such as a hollow molded object, deteriorates very much.

The polyester resin of the present invention, in which the increase in the amount of cyclic trimers when melted at a temperature of 290 ° C. for 60 minutes is 0.50% by weight or less, deactivates the polycondensation catalyst of polyester obtained after melt polycondensation or after solid phase polymerization. It can manufacture by doing.

As a method of deactivating the polycondensation catalyst of a polyester resin, the method of contact-processing a polyester chip with water, steam, or a steam containing gas after melt polycondensation or after solid-phase polymerization is mentioned.

In order to achieve the above object, a method of contacting a polyester chip with water or steam or a vapor-containing gas is described below.

As a hot water treatment method, the method of immersion in water, the method of spraying water on a chip | tip with a shower, etc. are mentioned. As processing time, it is 5 minutes-2 days, Preferably it is 10 minutes-1 day, More preferably, it is 30 minutes-10 hours, As water temperature, 20-180 degreeC, Preferably 40-150 degreeC, More preferably, 50 ˜120 ° C.

Although the method of performing water treatment industrially below is illustrated, it is not limited to this. In addition, the processing method may be either a continuous method or a batch method, but a continuous method is preferable for industrial operation.

When the polyester chip is water-treated by a batch method, a silo-type treatment tank is mentioned. That is, the chip | tip of a polyester is taken in a silo by a batch system, and a process is performed. Alternatively, the chip of polyester may be taken into a rotating tubular treatment tank, and water treatment may be performed while rotating to make contact with water more efficient.

When the chip of polyester is subjected to water treatment in a continuous manner, the chip of polyester can be continuously and intermittently taken into the columnar treatment tank and water-treated. This conceptual diagram is shown in FIG.

In the case where the chip of polyester is brought into contact with steam or a vapor-containing gas for treatment, the steam or steam-containing gas or steam-containing air at a temperature of 50 to 150 ° C, preferably 50 to 110 ° C is preferably granulated. Per kg of polyester, it is supplied in an amount of 0.5 g or more as water vapor, or is present to contact the particulate polyester and water vapor. The contact between the chip and the water vapor of the polyester is usually performed for 10 minutes to 2 days, preferably 20 minutes to 10 hours.

Although the method of industrially performing the contact process of a granular polyester and water vapor or a steam containing gas is illustrated, it is not limited to this. In addition, the treatment method may be either continuous or batch.

When the chip of polyester is subjected to contact treatment with water vapor by a batch method, a silo type treatment apparatus is mentioned. That is, the chip of polyester is taken in a silo, and a contact process is performed by supplying steam or a steam containing gas by a batch system. Alternatively, the granular polyester may be taken in a rotary cylindrical contact treatment device, and the contact treatment may be performed while rotating to make contact more efficient.

When the chip of polyester is continuously contacted with water vapor, the granular polyester is continuously received from the upper part in the tower-type processing apparatus, and the water vapor is continuously supplied by cocurrent or countercurrent to contact with water vapor. You can.

As described above, when treated with water or steam, the granular polyester is drained by a water drainage device such as a vibrating sieve or Simon Carter as necessary, and then transferred to the next drying step.

Drying of the chip of polyester which carried out the contact treatment with water or water vapor can use the drying process of polyester normally used. As a method of continuously drying, the hopper type ventilation dryer which supplies the chip | tip of polyester from the upper part and vents dry gas from the lower part is normally used. As a method of reducing the amount of dry gas and drying efficiently, a continuous dryer of a rotary disk type heating method is used. A chip of polyester is supplied by supplying heating steam, a heating medium, etc. to a rotating disk or an outer jacket while passing a small amount of dry gas. It can be heated and indirectly dried.

As a dryer drying by a batch system, a double cone type rotary dryer is used, and drying can be carried out under a vacuum or under a small amount of drying gas. Alternatively, the drying may be carried out while passing dry gas under atmospheric pressure.

Although dry gas is not a problem as dry gas, dry nitrogen and dehumidifying air are preferable in terms of preventing molecular weight decrease due to hydrolysis or thermal oxidative decomposition of polyester.

By performing water or steam treatment on a polyester resin as mentioned above, the amount of oligomer increase after heat-melting the said polyester resin at the temperature of 290 degreeC can be suppressed.

In addition, by deactivating the catalyst, it is possible to suppress the transesterification reaction during melting such as molding, and the effect of preventing the dispersion ratio Mw / Mn of the molded body from becoming 3.0 or less is also expected.

When a polymer having a wide molecular weight distribution or a polymer having a large molecular weight, that is, a polyester having a molecular weight distribution ratio Mw / Mn of 3.0 or more is injection molded and melt mixed, the low molecular weight component improves the fluidity of the mixed melt. It is presumed that the effect of reducing the temperature of the molten body is suppressed and the generation of aldehydes such as acetaldehyde is suppressed. When the catalyst is deactivated, since the transesterification reaction between the mixed polyesters is suppressed, the molecular weight distribution is hardly readjusted during the melt retention in the molding machine, and the dispersion ratio Mw / Mn of the molecular weight distribution remains as it is 3.0 or more, It is estimated that the generation of aldehydes, such as acetaldehyde, is more suppressed than in the case of non-inactivated products because the fluidity improving effect of the molecular weight component is maintained as it is in the molding machine.

However, at the same intrinsic viscosity as the polyester resin after mixing, injection molding of only a single polyester resin having a dispersion ratio Mw / Mn of molecular weight distribution of 3.0 or less does not cause the fluidity improving effect by the low molecular polyester as described above. Therefore, the room temperature degree at the time of melting becomes higher than the case of the said mixture, and generation | occurrence | production of aldehydes, such as acetaldehyde, increases.

In addition, aldehydes such as acetaldehyde tend to be accelerated by the polymerization catalyst, and the catalyst is preferably deactivated in order to make the effect of the present invention higher.

In addition, as a deactivation method of a polymerization catalyst, it can also carry out by adding a phosphorus compound.

Examples of the phosphorus compound include phosphoric acid compounds, phosphonic acid compounds, phosphinic acid compounds, phosphorous acid compounds, aphosphonic acid compounds, and aphosphinic acid compounds.

Specific examples of the phosphoric acid compound include phosphoric acid, dimethyl phosphate, diethyl phosphate, dipropyl phosphate, dibutyl phosphate, diamyl phosphate, dihexyl phosphate, trimethyl phosphate, triethyl phosphate, tripropyl phosphate and tributyl phosphate. And triamyl phosphate, trihexyl phosphate, ester of phosphoric acid and alkylene glycol, and the like.

As a specific example of a phosphonic acid type compound, for example, methyl phosphonic acid, methyl phosphonic acid dimethyl, methyl phosphonic acid diphenyl, phenyl phosphonic acid, phenyl phosphonic acid dimethyl, phenyl phosphonic acid diphenyl, benzyl phosphonic acid dimethyl, benzyl phosphone Acid diethyl, triethylphosphonoacetate, tributylphosphonoacetate, tri (hydroxyethyl) phosphonoacetate, tri (hydroxypropyl) phosphonoacetate, tri (hydroxybutyl) phosphonoacetate, and the like.

As a specific example of a phosphinic acid type compound, diphenylphosphinic acid, methyl diphenylphosphinic acid, phenyl diphenylphosphinic acid, phenylphosphinic acid, phenylphosphinic acid methyl, phenylphosphinic acid phenyl, 2-carboxyethyl methyl methyl phosphate, for example. Pinic acid, 2-carboxyethyl-ethylphosphinic acid, 2-carboxyethyl-propylphosphinic acid, 2-carboxyethyl-phenylphosphinic acid, 2-carboxyethyl-m-toluylphosphinic acid, 2-carboxyethyl-p-toluyl Phosphinic acid, 2-carboxyethyl-xylylphosphinic acid, 2-carboxyethyl-benzylphosphinic acid, 2-carboxyethyl-m-ethylbenzylphosphinic acid, 2-carboxymethyl-methylphosphinic acid, 2-carboxymethyl-ethylphosphate Pinic acid, 2-carboxyethyl-propylphosphinic acid, 2-carboxymethyl-phenylphosphinic acid, 2-carboxymethyl-m-toluylphosphinic acid, 2-carboxymethyl-p-toluylphosphinic acid, 2-carboxymethyl-crease Silylphosphinic acid, 2-carboxymethyl-benzylphosphinic acid, 2-carboxymethyl-m-ethylbenzylphosphine , And the like can be mentioned those of the cyclic acid anhydride, or a methyl ester, ethyl ester, propyl ester, butyl ester, glycol ester, glycol propionaldehyde, and esters of butane diol.

Specific examples of the phosphorous acid compound include, for example, phosphorous acid and dimethyl phosphite, diethyl phosphite, dipropyl phosphite, dibutyl phosphite, diamyl phosphite, dihexyl phosphite, trimethyl phosphite, and triethyl phosphite. , Triphenylphosphite, tris (2,4-di-tert-butylphenyl) phosphite, tetrakis (2,4-di-tert-butylphenyl) 4,4'-biphenylenediphosphite, phosphorous acid and alkyl Ester with lene glycol, etc. are mentioned.

As a specific example of an aphosphonic acid type compound, methyl aphosphonic acid, dimethyl methylphosphonic acid, methyl aphosphonic acid diphenyl, phenyl aphosphonic acid, phenyl aphosphonic acid dimethyl, phenyl aphosphonic acid diphenyl, etc. are mentioned, for example. .

As a method of adding a phosphorus compound, a method of adding during polycondensation, a method of immersing a chip in a phosphorus compound solution, in particular an aqueous solution of phosphoric acid, a method of adding as a masterbatch, etc. may be mentioned. In addition, these phosphorus compounds may be in a state copolymerized with polyester. At this time, a phosphorus compound is added to a polyester of a catalyst (for example, Ge, Sb) that does not significantly decrease the catalytic activity with a phosphorus compound, and the catalytic activity is reduced with a phosphorus compound (for example, Ti and Al). It is also preferable to blend with polyester. Thereby, the polyester which contained the phosphorus compound and raised molecular weight to the target molecular weight can be obtained easily.

In addition, in the case of performing a dephosphorization treatment of the polycondensation catalyst of a polyester resin using a phosphorus compound in the form of a chip, it is preferable to use a method of determining the molded body after molding as a measuring method for determining the deactivation effect. .

Moreover, although the transesterification reaction of polyester occurs at the time of shaping | molding by deactivating a catalyst, this transesterification reaction can be suppressed and the conditions at the time of shaping | molding can be taken more widely.

Moreover, the difference in crystallization temperature at the time of temperature rising of the polyester which comprises the polyester resin of this invention is less than 10 degreeC, Preferably it is less than 8 degreeC, More preferably, it is less than 7 degreeC, Especially preferably, it is less than 5 degreeC. When the difference in crystallization temperature at the time of temperature rising exceeds 10 degreeC, the crystallization rate variation of the obtained molded object becomes large. As a result, for example, since the fluctuation of the crystallization degree of the heat-crystallized hollow molded object sphere is large, the dimensional fluctuation of the sphere is large, resulting in poor capping property and leakage of the contents. Here, when the polyester resin of this invention becomes two or more types of polyester, the difference of the crystallization temperature at the time of temperature rising is the value of the polyester which has the crystallization temperature at the highest temperature, and the polycrystal which has the lowest crystallization temperature at the time of temperature rising. The difference of the value of ester is shown.

When the polyester resin of this invention has at least two types of polyester as a main component as mentioned above, it can manufacture by controlling suitably the kind and addition amount of said polycondensation catalyst, melt polycondensation, solid-state polymerization conditions, etc. . Moreover, it can also be obtained by the method of impacting the polyester chip obtained in this way, and the method of mix | blending a polyolefin resin, especially polyethylene, a polyamide resin, a polyoxymethylene resin, etc. as demonstrated below.

The shape of the polyester chip of this invention may be any of cylindrical shape, square shape, spherical shape, or flat plate shape. The average particle diameter is normally 1.0-4 mm, Preferably it is 1.0-3.5 mm, More preferably, it is the range of 1.0-3.0 mm. For example, in the case of a cylindrical shape, it is practical that length is 1.0-4 mm, and diameter is about 1.0-4 mm. In the case of spherical particles, it is practical that the maximum particle size is 1.1 to 2.0 times the average particle size, and the minimum particle size is 0.7 times or more the average particle size. In addition, the average weight (W) of the chip is practically in the range of 5 to 50 mg / piece. In addition, when it is necessary to improve the solid-state polymerization rate or to reduce the content of aldehydes more effectively, the average weight (W) of the chip is also preferably 1 to 5 mg / piece.

Moreover, the ratio of the average weight (W) of the polyester which comprises the polyester resin of this invention is 0.80-1.20, Preferably it is 0.85-1.15, More preferably, it is 0.90-1.10, More preferably, it is 0.95-1.05, Most preferably, it is 0.97-1.03. In addition, when the ratio of the average weight (W) is less than 0.80, the generation of aldehydes at the time of molding increases, and in order to manufacture chips, the equipment cost is high, such as using a special nozzle, which is not preferable. Moreover, when it exceeds 1.20, it will become difficult to melt at the time of shaping | molding, and low temperature shaping | molding becomes difficult and becomes a problem. In particular, when used for the heat-resistant hollow stretched molded article, when the above ratio is outside the range of 0.95 to 1.05, the effect of reducing aldehydes such as acetaldehyde and improving transparency is worsened, and the amount of the compound is not uniform. This tends to occur, which is not preferable because it causes transparency or thickness unevenness of the polyester unstretched molded body or stretched molded body. Here, when the polyester resin of this invention becomes two or more types of polyester, the difference of the said average weight (W) is the difference of the value of the polyester of the largest average weight and the value of the polyester of the smallest average weight. Indicates.

Moreover, the difference of the crystallinity degree of the polyester chip which comprises the polyester resin of this invention is 15% or less, Preferably it is 10% or less, More preferably, it is 8% or less. If the difference in crystallinity is more than 15%, the difference in meltability between the polyesters is so large that the effect of improving the fluidity deteriorates. As a result, the transparency of the polyester unstretched molded body or the stretched hollow molded body is improved and the acetaldehyde content is reduced. It is not preferable because the effect is lost, and the amount of the compounding non-uniformity of the polyester tends to occur, which causes the transparency of the polyester unstretched molded article and the stretched hollow molded article and the fluctuation of acetaldehyde content. Here, when the polyester resin of this invention consists of two or more types of polyester, the difference of the said crystallinity degree means the difference of the crystallinity degree of largest polyester and minimum polyester regarding crystallinity degree. Here, the crystallinity of the chip is calculated by calculation from the density of the chip determined by the following method.

When the polyester resin of this invention becomes said polyester A and polyester B, for example, these can be obtained by mixing them uniformly at a predetermined ratio. For example, the method of dry blending the polyester A and the polyester B with a tumbler, a V-type blender, a Henschel mixer, a static mixer, or the like, further dry blending the mixture The method of melt-mixing one or more times with a single screw extruder, a twin screw extruder, a kneader, etc. are mentioned. Specifically, it is common to mix the above-mentioned polyester A and polyester B uniformly in predetermined | prescribed ratio by the said suitable method in chip form, and to dry, and to provide for shaping | molding.

Moreover, polyamide, polyesteramide, a low molecular weight amino group containing compound, and a hydroxyl group containing compound can be mix | blended with the polyester resin of this invention as a capture material of an aldehyde compound.

As a polyamide mix | blended as a trapping material of an aldehyde compound, at least 1 sort (s) of polyamide chosen from aliphatic polyamide and partially aromatic polyamide is mentioned.

Specific examples of the aliphatic polyamides include nylon 6, nylon 11, nylon 12, nylon 66, nylon 69, nylon 610, nylon 6/66, nylon 6/610, and the like.

Preferred examples of the partially aromatic polyamides include a structure derived from aliphatic dicarboxylic acid and mixed xylylenediamine containing methacrylyylenediamine or methaxylylenediamine and up to 30% of paraxylylenediamine. It is a metha xylylene group containing polyamide which contains a unit at least 20 mol% or more in a molecular chain, More preferably, it is 30 mol% or more, Especially preferably, it is 40 mol% or more.

 In addition, the partially aromatic polyamide may contain a structural unit derived from a trivalent or higher polyhydric carboxylic acid such as trimellitic acid or pyromellitic acid within a substantially linear range.

As an example of these polyamides, homopolymers, such as polymethaxylylene azipamide, polymethaxylylene sebacamide, polymethaxylylenesperamide, etc., and methaxylylenediamine / adipic acid / isophthalic acid copolymer, meta Xylylene / paraxylyleneazipamide copolymer, methaxylylene / paraxylylenepiperamide copolymer, methaxylylene / paraxylylene aramid copolymer, methaxylylenediamine / adipic acid / Isophthalic acid / (epsilon) -caprolactam copolymer, a metha xylylenediamine / adipic acid / isophthalic acid / (omega) -aminocapronic acid copolymer, etc. are mentioned.

Further preferred examples of the partially aromatic polyamide include at least 20 mol% or more, more preferably 30 mol% or more, of the structural units derived from aliphatic diamine and at least one acid selected from terephthalic acid or isophthalic acid, Especially preferably, it is polyamide containing 40 mol% or more.

Examples of these polyamides include polyhexamethylene terephthalamide, polyhexamethylene isophthalamide, hexamethylenediamine / terephthalic acid / isophthalic acid copolymer, polynonamethylene terephthalamide, polynonamethylene isophthalamide, nonnamethylenediamine / terephthalic acid / Isophthalic acid copolymer, nona methylenediamine / terephthalic acid / adipic acid copolymer, etc. are mentioned.

Further preferred examples of the partially aromatic polyamide include lactams such as ε-caprolactam and laurolactam, and aminocarboxylic acids such as aminocaproic acid, in addition to at least one acid selected from aliphatic diamine, terephthalic acid or isophthalic acid. At least 20 mol% or more of a structural unit derived from at least one acid selected from aliphatic diamine and terephthalic acid or isophthalic acid obtained by using an aromatic aminocarboxylic acid such as para-aminomethyl benzoic acid as a copolymerization component. More preferably 30 mol% or more, particularly preferably 40 mol% or more.

Examples of these polyamides include hexamethylenediamine / terephthalic acid / ε-caprolactam copolymer, hexamethylenediamine / isophthalic acid / ε-caprolactam copolymer, hexamethylenediamine / terephthalic acid / adipic acid / ε-caprolactam copolymer, and the like. Can be mentioned.

Further, as the polyester amide, polyester amide, terephthalic acid prepared from terephthalic acid, 1,4-cyclohexanedimethanol and polyethyleneimine, isophthalic acid, 1,4-cyclohexanedimethanol and hexamethylenediamine Polyesteramides prepared from adipic acid, 1,4-cyclohexanedimethanol and hexamethylenediamine, polyesteramides prepared from terephthalic acid, 1,4-cyclohexanedimethanol and bis (p-aminocyclohexyl) methane and And mixtures thereof.

It is preferable that the secondary transition point of the polyamide and polyesteramide used is 50-120 degreeC measured by DSC (differential scanning calorimetry). When the secondary transition point is less than 50 ° C, it is not preferable because the secondary transition point is fused at the time of the drying step or extrusion with the polyester resin, and cannot be extruded quantitatively. Moreover, when it exceeds 120 degreeC, when extending | stretching a polyester unstretched molded object, it does not extend uniformly and a thickness nonuniformity arises etc., and is unpreferable.

The shape of the chip of polyamide or polyesteramide blended with the polyester resin of the present invention may be any of a cylinder, a square, a spherical shape or a flat plate shape. The average particle diameter is normally 1.0-5 mm, Preferably it is 1.2-4.5 mm, More preferably, it is the range of 1.5-4.0 mm. For example, in the case of a cylindrical shape, it is practical that length is 1.0-4 mm, and diameter is about 1.0-4 mm. In the case of spherical particles, it is practical that the maximum particle size is 1.1 to 2.0 times the average particle size, and the minimum particle size is 0.7 times or more the average particle size. Moreover, the weight of a chip | tip is practical in the range of 1-50 mg / piece.

As the low molecular weight amino group-containing compound, aliphatic amine compounds such as stearylamine, 1,8-diaminonaphthalate, 3,4-diaminobenzoic acid, 2-aminobenzamide, 4,4'-diaminodiphenyl Aromatic amine compounds such as methane, triazine compounds such as melamine and benzoguanamine, and amino acids.

Moreover, as a hydroxyl-containing compound, polyvinyl alcohol, ethylene vinyl alcohol polymer, sugar alcohol, a trimethylol propane etc. are mentioned.

These polyamide compounds, low molecular weight amino group containing compounds, or hydroxyl group containing compounds may be used independently, or may be mixed and used in a suitable ratio.

The aldehyde compound trapping material may be used in an amount of 0.001 to 5 parts by weight, preferably 0.01 to 3 parts by weight, and more preferably 0.1 to 2 parts by weight based on 100 parts by weight of the polyester resin of the present invention.

The aldehyde compound trapping material can be blended by adding a predetermined amount of the aldehyde compound trapping material in any reaction step of producing a polyester polymer from the production of a low polymerization degree oligomer of polyester. For example, the aldehyde compound trapping material is added to a reactor such as an esterification reactor or a polycondensation reactor as a suitable type such as fine grains, powdery phase, or melted material, or the reactor of the next step from the above reactor. In the transport piping of the polyester reactant to the furnace, the aldehyde compound trapping material or a mixture of this and the polyester may be introduced and mixed in a molten state. Furthermore, it is also possible to solid-phase polymerize the chip obtained as needed under high vacuum or inert gas atmosphere.

Moreover, it is also possible to obtain by the method of mixing a polyester resin and an aldehyde compound capture | acquisition material by a conventionally well-known method, or the method of mixing an aldehyde compound capture | acquisition material in the mixture of 2 or more types of polyester. For example, two kinds of polyester chips different from polyamide chips and IV are dry blended with a tumbler, a V-type blender, a Henschel mixer, etc., and the dry blended mixture is a single screw extruder, a twin screw extruder, a kneader or the like. For example, the melt-mixed one or more times, and further, the solid-phase polymerization of chips from the molten mixture under high vacuum or inert gas atmosphere as necessary.

Moreover, the method of attaching the solution which melt | dissolved the said polyamide in the solvent, such as hexafluoroisopropanol, to the surface of a polyester chip, impacts the said polyester with the said member in the space where the member of the said polyamide exists. And a method of attaching the polyamide to the polyester chip surface by bringing it into contact.

Moreover, it is preferable to mix | blend 0.1 ppb-50000 ppm of at least 1 sort (s) of resin chosen from the group which consists of a polyolefin resin and a polyacetal resin to the polyester resin of this invention. The blending ratio of the resin to the polyester resin used in the present invention is 0.1 ppb to 10000 ppm, preferably 0.3 ppb to 1000 ppm, more preferably 0.5 ppb to 100 ppm, still more preferably 1.0 ppb to 1 ppm, particularly preferably 1.0 ppb to 45 ppb. If the blending amount is less than 0.1 ppb, the crystallization rate becomes very slow, and crystallization of the oral cavity of the hollow molded body becomes insufficient. If the cycle time is shortened, the shrinkage of the oral cavity does not fall within the prescribed range, resulting in poor capping. The contamination of the stretched heat-setting mold for molding the heat-resistant hollow molded body is severe, and in order to obtain a transparent hollow molded body, the mold must be cleaned frequently. When the content exceeds 50000 ppm, the crystallization rate is increased, and the crystallization of the oral cavity of the hollow molded body becomes excessive. Therefore, the shrinkage of the oral cavity is not within the prescribed range, resulting in poor capping and leaking the contents. Unstretched molded articles for the body are whitened, and therefore normal stretching is impossible. Moreover, in the case of a sheet-like thing, when it exceeds 50000 ppm, transparency will become very bad, extending | stretching property will also worsen, and normal extending | stretching will not be possible, and only the poor transparency film with a large thickness nonuniformity is obtained.

As polyolefin resin mix | blended with the polyester resin of this invention, polyethylene-type resin, polypropylene resin, or (alpha)-olefin resin is mentioned. In addition, these resins may be crystalline or amorphous.

As polyethylene-type resin mix | blended with the polyester resin of this invention, the homopolymer of ethylene, ethylene, propylene, butene-1, 3-methylbutene-1, pentene-1, 4-methylpentene-1, Other α-olefins having 2 to 20 carbon atoms, such as hexene-1, octene-1, and decene-1, vinyl acetate, vinyl chloride, acrylic acid, methacrylic acid, acrylic acid ester, methacrylic acid ester, styrene, and unsaturated epoxy compounds Copolymers with vinyl compounds, such as these, etc. are mentioned. Specifically, for example, ultra low, low, medium, high density polyethylene (branched or linear) ethylene homopolymer, ethylene-propylene copolymer, ethylene-butene-1 Copolymer, ethylene-4-methylpentene-1 copolymer, ethylene-hexene-1 copolymer, ethylene-octene-1 copolymer, ethylene-vinyl acetate copolymer, ethylene-acrylic acid copolymer, ethylene-methacrylic acid copolymer And ethylene resins such as ethylene-ethyl acrylate copolymer.

Moreover, as a polypropylene resin mix | blended with the polyester resin of this invention, for example, the homopolymer of propylene, propylene, ethylene, butene-1,3-methylbutene-1, pentene-1,4-methylpentene- 1, hexene-1, octene-1, decene-1, other α-olefins having about 2 to 20 carbon atoms, vinyl acetate, vinyl chloride, acrylic acid, methacrylic acid, acrylic acid ester, methacrylic acid ester, styrene, etc. Copolymers with vinyl compounds or copolymers with dienes such as hexadiene, octadiene, decadiene, dicyclopentadiene, and the like. Specifically, propylene resins such as propylene homopolymer (atactic, isotactic, syndiotactic polypropylene), propylene-ethylene copolymer, and propylene-butene-1 copolymer Can be mentioned.

Moreover, as alpha-olefin resin mix | blended with the polyester resin of this invention, the homopolymer of C2-C8 alpha-olefins, such as 4-methylpentene-1, those alpha-olefins, ethylene, propylene, butene And copolymers with other α-olefins having about 2 to 20 carbon atoms, such as -1,3-methylbutene-1, pentene-1, hexene-1, octene-1, and decene-1. Specifically, butene-1 resin and 4-methylpentene, such as butene-1 homopolymer, 4-methylpentene-1 homopolymer, butene-1-ethylene copolymer, butene-1-propylene copolymer, for example and the like-1 and C ₂ ~ C ₁₈ of copolymers of α- olefin.

Moreover, as a polyacetal resin mix | blended with the polyester resin of this invention, a polyacetal homopolymer and a copolymer are mentioned, for example. As a polyacetal homopolymer, the melt flow ratio (MFR) measured at 190 degreeC and a load of 2160 g by the measuring method of 1.40-1.42 g / cm <3> and ASTMD-1238 measured by the measuring method of ASTM-D792 is 0.5- Preference is given to polyacetals in the range of 50 g / 10 min.

Moreover, as a polyacetal copolymer, the melt flow ratio (MFR) measured at 190 degreeC and a load of 2160g by the measuring method of 1.38-1.43g / cm <3> and ASTMD-1238 measured by the density method measured by the measuring method of ASTM-D792 is Preference is given to polyacetal copolymers in the range of 0.4-50 g / 10 min. Ethylene oxide and a cyclic ether are mentioned as these copolymerization components.

When mix | blending the said polyolefin resin etc. with the polyester resin of this invention, the method of melt-kneading by adding directly resins, such as said polyolefin resin, to the said polyester resin or polyester which comprises this so that content may become the said range. In addition to the conventional methods such as addition and melting kneading as a masterbatch, the resin is prepared in the step of producing the polyester, for example, during melt polycondensation, immediately after melt polycondensation, immediately after preliminary crystallization, During the polymerization, in any one of the steps immediately after the solid phase polymerization or the like, or in the process from the end of the manufacturing step to the molding step, the polymer is directly added as a powder or the chip of the polyester is added. Melting and kneading | mixing by the method of incorporating by contacting the said resin member under flow conditions, etc., or after said contact processing. It is also possible to use such a method.

Here, as a method of bringing a polyester chip into contact with said resin member under flow conditions, it is preferable to make the polyester chip collide-contact with the said member in the space in which the said resin member exists, Specifically, For example, during the manufacturing process such as immediately after melt polycondensation of polyester, immediately after preliminary crystallization, immediately after solid phase polymerization, and during filling and discharging of a transport container in a transportation step as a product of a polyester chip, and further, a polyester chip When the molding machine is inserted in the molding step of the molding machine, a part of the energy transport pipe, the gravity transport pipe, the silo, the magnet part of the magnet catcher, etc. are made of the resin, or the resin film, sheet, molded body, etc. are attached. The number of rods, reticulated bodies, etc. in the transfer path or lining the resin; By installing a first member, or there may be mentioned a method of transferring the polyester chips. Although contact time with the said member of a polyester chip is an extreme time of about 0.01 second-several minutes normally, a trace amount of the said resin can be mixed in polyester resin.

The polyester unstretched molded article of the present invention is melted by melt extrusion molding in the form of a film, sheet, hollow molded article, or the like by a melt molding method using an extrusion molding machine, an injection molding machine or the like which is generally used. It can be obtained in the form of a preform obtained by compression molding the ingot. Moreover, the polyester unstretched molded object of this invention can be made into a polyester stretched molded object using the arbitrary extending | stretching method of uniaxial stretching, sequential biaxial stretching, and simultaneous biaxial stretching. Moreover, it can also be shape | molded in cup shape or a tray shape by pressure forming and vacuum forming.

In addition, it is possible to improve the mechanical strength by stretching the sheet-like article made of the polyester resin of the present invention in at least one axial direction. The stretched film made of the polyester resin of the present invention is formed by using any stretching method of sheet-like article obtained by injection molding or extrusion molding, uniaxial stretching, sequential biaxial stretching, and simultaneous biaxial stretching, which are usually used for stretching PET. do. Moreover, it can also be shape | molded in cup shape or tray shape by pressure forming and vacuum forming.

When the polyester unstretched molded product of the present invention is to be obtained from the polyester resin of the present invention, a transesterification reaction occurs during melt kneading. Therefore, melt kneading conditions need to be adjusted such as temperature, residence time, shear rate, screw configuration, and the like so that the dispersion ratio Mz / Mn of the molecular weight distribution of the polyester unstretched molded body is not less than 3.30. Specifically, the temperature, residence time, and shear rate should not be raised more than necessary within the range that can be uniformly kneaded. The screw configuration requires more mixing or reversing screws than necessary to ensure plug flow. May be added and the melt residence time may be as short as possible.

The polyester resin is generally stored in an air atmosphere until the polymer is polymerized and then molded, and it is hygroscopic during this period. Moisture absorption rate is about 300 ~ 4000 ppm, depending on the storage period. When the polyester resin of this invention has at least 2 or more types of polyester as a main component, the moisture content difference of each polyester before melt molding is 100 ppm or less, Preferably it is 80 ppm or less, More preferably, it is 50 ppm or less, Especially preferable Preferably 30 ppm or less, most preferably 10 ppm or less. Moisture content of polyester with lower ultimate viscosity (hereinafter sometimes referred to as low IV-polyester) from the water-receiving rate of polyester with higher ultimate viscosity (hereinafter sometimes referred to as high IV-polyester) When the value obtained by subtracting exceeds 100 ppm, the high IV-polyester is hydrolyzed in the molding machine to lower the intrinsic viscosity, and as a result, the IV difference between both polyesters becomes smaller than before molding, and the fluidity as described above. The improvement effect cannot be exhibited, transparency deteriorates, and content of aldehydes, such as acetaldehyde, also becomes high. In addition, when the value obtained by subtracting the moisture content of the high IV polyester from the moisture content of the low IV polyester is more than 100 ppm, as a result of lowering the extreme viscosity by hydrolysis in the molding machine, The IV difference between both polyesters is greater. In particular, in the case of a polyester resin having a difference in intrinsic viscosity between 0.30 dl / g and before forming, the difference in intrinsic viscosity also becomes larger, resulting in a problem of poor transparency and whitening of the formed molded article, resulting in poor transparency. Here, when the polyester resin of this invention consists of two or more types of polyester, the difference of the said moisture content means the moisture content difference of the largest polyester and the minimum polyester regarding moisture content.

As a condition for molding the polyester unstretched molded article of the present invention, a molten resin temperature is 10 to 35 ° C higher than the melting point of the resin by heating a barrel or a hot runner such as an injection molding machine. It is important to set the temperature so as to be in a range of preferably 12 to 33 ° C high temperature, more preferably 15 to 30 ° C high temperature. The molten resin temperature herein refers to a temperature at which a resin injected from a nozzle tip such as an injection molding machine is immediately measured by, for example, a thermocouple thermometer or the like. Here, melting | fusing point is the value calculated | required by the DSC measuring method.

As a representative example, the molding of the polyester molded body of the present invention will be described in more detail. Since the polyester resin is hygroscopic, the moisture is reduced to about 100 ppm or less, preferably 50 ppm or less by heat drying under reduced pressure or heat drying under an inert gas, and then a film, sheet, The molded object which consists of a container and other packaging materials can be shape | molded.

As a condition relating to the production of unstretched molded articles of PET, the molten resin temperature is 260 to 295 ° C, preferably 262 to 290 ° C, more preferably 265 to 285 ° C, most preferably by heating a barrel or a hot runner such as an injection molding machine. It is important to set so that it is in the range of 265 ~ 280 ℃.

The melt residence time in the molding machine is determined by arbitrarily setting the shape of the extruder screw, the selection of L / D, the extrusion amount, etc. in the case of extrusion molding, and the cycle time and the metering of the injection molding machine in the case of injection molding. By arbitrarily setting the stroke (screwback amount) or the like, it is set in the range of 10 to 500 seconds, preferably 20 to 200 seconds, more preferably 30 to 150 seconds. Here, the melt residence time is a residence time in a state in which the resin is melted in the molding machine, and specifically, refers to a time in which the resin is melted and held in a cylinder, a hot runner or a die in the molding machine.

In the case of injection molding, when the melt residence time is t, t is given by the following equation.

t = W × S / P (5)

Here, W: Weight (g) of molten resin in cylinders, such as an injection molding machine, and a hot runner

S: time of one molding cycle in seconds

P: Molded article weight (g) of molding 1 shot

In the present invention, by controlling the molten resin temperature in the range of 260 to 295 ° C and setting the melt residence time in the range of 10 to 500 seconds, at least two kinds of polyesters mainly composed of ethylene terephthalate as the main repeating unit are main components. From polyester resin to be included as a low aldehyde content such as acetaldehyde, excellent flavor retention, excellent transparency, and nonuniformity of transparency (e.g. There is no generation | occurrence | production of a cargo or a bed material, and there is no problem in the shape of the oral part after crystallization, and the unstretched molded object for hollow molded objects can be obtained. Especially in the case of thickness stretched molded bodies, such as bottles, these effects become remarkable.

When the molten resin temperature is less than 260 ° C, the torque load of an injection molding machine or the like is large, so that molding is difficult, and the resulting unstretched molded body is extremely poor in transparency, and the sheet-like article has a large variation in thickness. Moreover, at the temperature exceeding 295 degreeC, thermal decomposition becomes severe and aldehyde content, such as acetaldehyde, becomes high and it is a problem. If the melt residence time is less than 10 seconds, the transparency of the unstretched molded article becomes poor due to the lack of melting, and if it exceeds 500 seconds, the transparency of the unstretched molded article becomes very good, but the content of aldehydes such as acetaldehyde is increased, and the molding cycle This long time will reduce the productivity of the unstretched molded body.

Hereinafter, the specific manufacturing method for the various uses in case of PET is demonstrated easily. In manufacturing a stretched film, extending | stretching temperature is 80-130 degreeC normally. Although extending | stretching may be uniaxial or biaxial, Preferably it is biaxial stretching from a film practical physical property viewpoint. The stretching ratio is usually in the range of 1.1 to 10 times, preferably in the range of 1.5 to 8 times, in the case of uniaxial stretching, and in the longitudinal direction and in the transverse direction in the case of biaxial stretching, usually in the range of 1.1 to 8 times, preferably in the range of 1.5 to 5 times. The range may be performed. In addition, the longitudinal magnification / horizontal magnification is usually 0.5 to 2, preferably 0.7 to 1.3. The obtained stretched film can be further heat-fixed to improve heat resistance and mechanical strength. Heat setting is normally 120-240 degreeC under tension, Preferably it is 150-230 degreeC, Usually, several seconds-several hours, Preferably it is carried out for several tens of seconds-several minutes. The thickness of the stretched film is about 5 to 100 microns.

In addition, in manufacturing a stretched blow molded object, the polyester unstretched molded object of this invention is stretch-blended, and the apparatus conventionally used for blow molding of PET can be used. Specifically, for example, an unstretched molded body is molded once by injection molding or extrusion molding, and processed as it is, or after processing the oral cavity and the bottom, and then reheated it, and the hot parison method or cold Biaxially stretch blow molding methods such as the cold parison method are applied. The polyester unstretched molded body is stretched after unstretched heating to temperature control at about 90 to 110 ° C, preferably about 95 to 105 ° C. Drawing temperature is 70-120 degreeC normally, Preferably it is 90-110 degreeC.

In the case of the pressure-resistant and heat-resistant polyester stretched hollow molded product, the stretch ratio is 5 to 15 times, preferably 7 to 12 times the area stretch ratio. In order to impart heat resistance, the film is blown and then heat-set by holding at a mold temperature of 100 to 180 ° C, preferably 110 to 150 ° C for at least 1 second, preferably at least 3 seconds.

Moreover, in the case of highly heat resistant polyester stretched hollow molded object, it is preferable that a draw ratio is 5-10 times, preferably 6-8 times in area draw ratio. The obtained polyester stretched blow molded body crystallizes the oral part, particularly in the case of a beverage requiring heat charging such as juiced soda. In order to impart heat resistance to the mouth section, the mouth section of the polyester unstretched molded body obtained by injection molding or extrusion molding is crystallized in a far infrared ray or near infrared heater installation oven, or after mouth molding, the mouth section is crystallized with the heater. . In addition, in order to impart heat resistance to the trunk portion, the film is blown and then heat-set by holding at a mold temperature of 110 to 230 ° C, preferably 120 to 210 ° C for 1 to 30 seconds, and preferably for 1 to 20 seconds. .

After the blow blow molding as described above, a cooling gas such as nitrogen or air is blown into the molded body and cooled.

Moreover, it is also possible to obtain a stretch blow molded body by the so-called compression molding method in which the preform obtained by compression molding the molten ingot cut after melt extrusion of the polyester resin of the present invention.

In the polyester resin of the present invention, if necessary, a known ultraviolet absorber, antioxidant, infrared absorber, oxygen trapping agent, lubricant added from the outside, lubricants precipitated internally during the reaction, release agents, nucleating agents, stabilizers, charging In order to improve oxygen permeability, various additives, such as an inhibitor, a blue agent, dye, and a pigment, you may mix | blend a polyamide resin from methacrylicylenediamine, adipic acid, etc.

Moreover, when the polyester stretched molded object obtained from the polyester unstretched molded object of this invention is a stretched film, in order to improve handling properties, such as activity, winding property, blocking resistance, calcium carbonate, Inorganic particles such as magnesium carbonate, barium carbonate, calcium sulfate, barium sulfate, lithium phosphate, calcium phosphate and magnesium phosphate, organic salt particles such as calcium oxalate and terephthalate such as calcium, barium, zinc, manganese and magnesium, and divinylbenzene And inert particles such as crosslinked polymer particles such as styrene, acrylic acid, methacrylic acid, acrylic acid or methacrylic acid alone or a copolymer of vinyl monomers.

The dispersion ratio Mw / Mn of the molecular weight distribution of the polyester unstretched molded article or polyester stretched molded article of the present invention obtained as described above using the polyester resin of the present invention is 3.00 or more, preferably 3.05 or more, and more preferably 3.10 or higher. When dispersion ratio Mw / Mn of molecular weight distribution is less than 3.00, since the transparency of the said molded object is bad and aldehydes, such as acetaldehyde, of the said molded object cannot be reduced, it is unpreferable. In addition, only a polyester stretched molded article having a lower mechanical strength is obtained.

Further, the dispersion ratio Mz / Mn of the molecular weight distribution of the polyester unstretched molded product or the polyester stretched molded product of the present invention is 3.30 or more, preferably 3.33 or more, more preferably 3.35 or more, particularly preferably 3.37 or more. When dispersion ratio Mz / Mn of molecular weight distribution is less than 3.30, since the transparency of the said molded object is bad as mentioned above, and aldehydes, such as acetaldehyde, of the said molded object cannot be reduced, it is unpreferable. In addition, only a polyester stretched molded article having a lower mechanical strength is obtained.

Moreover, it is preferable that content of the aldehydes of the polyester unstretched molded object or polyester stretched molded object of this invention is 50 ppm or less, Preferably it is 30 ppm or less, More preferably, it is 20 ppm or less.

In addition, when the polyester stretched molded article of the present invention is a polyester resin containing ethylene terephthalate as a main repeating unit, and this is used as a material for a low flavor beverage container such as mineral water, The acetaldehyde content is preferably 15 ppm or less, preferably 12 ppm or less, more preferably 10 ppm or less, and most preferably 7 ppm or less.

In addition, the formaldehyde content of the polyester-stretched hollow molded product of the present invention is preferably 5 ppm or less, preferably 3 ppm or less, more preferably 2 ppm or less, and most preferably 1 ppm or less.

The free ethylene glycol content of the polyester-stretched hollow molded product of the present invention is 50 ppm or less, preferably 40 ppm or less, more preferably 30 ppm or less, most preferably 20 ppm or less, and free diethylene glycol content. Silver is 20 ppm or less, preferably 15 ppm or less, more preferably 13 ppm or less, and most preferably 10 ppm or less.

In addition, when the polyester unstretched molded object of the present invention is a polyester resin containing ethylene terephthalate as a main repeating unit, the crystallization temperature (Tc1) at the time of temperature increase is 140 to 175 ° C, and the crystallization temperature at the time of temperature reduction ( It is preferable that Tc2) is 160-190 degreeC. When Tc1 is less than 140 degreeC, it will whiten at the time of preheating before shaping | molding, and elongation will worsen and transparency will also worsen. When Tc1 exceeds 175 ° C, the crystallization treatment of the mouth portion of the hollow molded article for heat resistance is insufficient, and the mouth portion is deformed when heat-filling the beverage of high temperature, which causes the leaking after capping.

In addition, it is preferable that the polyester unstretched molded article or stretched hollow molded article of the present invention has an increased amount of cyclic trimer when it is melted at a temperature of 290 ° C. for 60 minutes at 0.40% by weight or less, and for this purpose, the polyester used is It can manufacture by deactivating the polycondensation catalyst of polyester obtained after melt polycondensation or after solid-phase polymerization as mentioned above. The amount of increase of the cyclic trimer when it melts for 60 minutes at the temperature of 290 degreeC becomes like this. Preferably it is 0.3 weight% or less, More preferably, it is 0.1 weight% or less. When the amount exceeds 0.4% by weight, cyclic trimers, linear monomers, and linear oligomers are increased during melting of the molding resin, and oligomer adhesion rapidly increases to vent holes in the molding die, making continuous production difficult. In addition, the flavor retention of the obtained polyester stretched blow molded product is deteriorated.

Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to these Examples.

In addition, the measuring method of a main characteristic value is demonstrated below.

The composition and each property of the polyester are measured after freezing and pulverizing the chips and mixing them sufficiently.

(1) Intrinsic viscosity of polyester (IV)

It was calculated | required from the solution viscosity at 30 degreeC in the 1,1,2,2- tetrachloroethane / phenol (2: 3 weight ratio) mixed solvent. IV of polyester resin was made into the weighted average value computed from IV of the polyester which comprises.

(2) Diethylene glycol content of polyester (henceforth "DEG content")

It decomposed | dissolved by methanol, and the amount of DEG was quantified by gas chromatography, and it represented by the ratio (mol%) with respect to the whole glycol component.

(3) Content (it calls "CT content" below) of cyclic trimer of polyester

300 mg of the frozen-pulverized sample is dissolved in 3 ml of a hexafluoroisopropanol / chloroform mixture (volume ratio = 2/3), and 30 ml of chloroform is further added and diluted. 15 ml of methanol is added to this, and a polymer is precipitated and filtered. The filtrate was evaporated to dryness, defined as 10 ml of dimethylformamide, and the cyclic trimer was quantified by high performance liquid chromatography.

(4) Amount of cyclic trimer increase (ΔCT amount) at the time of melting of polyester

The polyester resin is freeze-pulverized, and then 3 g of the dried polyester sample is placed in a glass test tube and immersed in an oil bath at 290 ° C. for 60 minutes under a nitrogen atmosphere for melting. The cyclic trimer increase amount at the time of melting is calculated | required by the following formula.

In addition, the cyclic trimer content before melting was made into the weighted average value of the cyclic trimer content of the polyester which comprises a polyester resin.

Annular trimer increase amount (weight%) at the time of melting =

Cyclic trimer content (wt%) after melting-Cyclic trimer content (wt%) before melting

In addition, when the cyclic trimer increase amount at the time of melting of a molded object is calculated | required, three pieces of about 1-3 mm size are cut out from the inlet of the molded object shape | molded by the following (16), and it is set as a sample.

(5) Acetaldehyde content (hereinafter referred to as "AA content") of polyester and AA increase amount before and behind molding (hereinafter referred to as "ΔAA amount")

A sample / distilled water = 1 g / 2 cc in a nitrogen-substituted glass ampoule was melted and subjected to extraction for 2 hours at 160 ° C. After cooling, acetaldehyde in the extract was measured by high sensitivity gas chromatography. , Concentration is expressed in ppm. In the case of the preform, a sample was taken from the inlet. The amount of ΔAA is the amount of AA of the chip before the molding of the molded product sample, but in the case of the dry blend composition molding, the average value of the amount of AA of the individual polyesters was taken as the amount of AA of the chip before molding.

(6) density (ρ) and crystallinity (CR) of polyester chips

The density (rho) of the chip | tip at 30 degreeC was measured in the density gradient tube of calcium nitrate / aqueous solution.

In the case of PET, the crystallinity was calculated from the following formula.

CR = 100ρ _c (ρ-ρ _a ) / ρ (ρ _c -ρ _a )

Where ρ is the density of the chip

ρ _a : amorphous density (1.335 g / cm 3)

ρ _c : crystal density (1.455 g / cm 3)

(7) Ratio of average weight (W) to average weight of polyester chip

The ratio of the average weight (W) and the average weight of the polyester chip measured the weight with respect to up to 100 dry polyester chips, after removing fine with ion-exchange water, and made the average value the average weight (W).

In this case, the selection of 100 chips was performed by removing chips of abnormal size. That is, 100 chips are randomly selected and the average weight (W) is calculated, and then, except for chips having a weight less than 0.5 W and chips having more than 2 W, the selected number of chips are randomly selected and replenished. The average value of 100 was recalculated. This was done until all 100 chips were within 0.5 W to 2 W.

In addition, the ratio of the average weight of polyester A and polyester B was calculated and calculated | required by the following formula from the average weight of each polyester chip calculated | required in this way.

Ratio of average weight = average weight of polyester A / average weight of polyester B

(8) Sodium content of calcium, calcium content

About 5 to 10 g of the sample is placed in a platinum crucible, incinerated at about 550 ° C, dissolved in 6N hydrochloric acid, evaporated to dryness, and the residue is dissolved in 1N hydrochloric acid. This solution was measured by atomic absorption spectrometry.

(9) Silicon content of polyester

About 5-10 g of a sample is put into a platinum crucible, it is incubated at about 550 degreeC, and it heat-dissolves by adding sodium carbonate, and melt | dissolves in 1N hydrochloric acid. This solution was measured by an inductively coupled plasma luminescence analyzer manufactured by Shimadzu Seisakusho.

(10) Measurement of the content of pine

About 0.5 kg of resin was combined with a wire mesh of nominal size 5.6 mm in accordance with JIS-Z8801 in a two-stage combination of sieve (A) and a wire mesh of nominal size of 1.7 mm (diameter of 20 cm) (B). The resultant was placed on a sieve and sieved at 1800 rpm for 1 minute with a shaking shaker SNF-7 made by Deraoka Co., Ltd. This operation was repeated and 20 kg of resins were sieved in total. However, when there is little fine content, the quantity of a sample is changed suitably.

The fine particles sieved under the sieve (B) were washed with 0.1% aqueous cationic surfactant solution, then washed with ion-exchanged water, and collected by filtration with a G1 glass filter manufactured by Iwaki Glass Co., Ltd. After drying for 2 hours at 100 degreeC in the dryer for every glass filter, they were cooled and weighed. Again, the same operation of washing and drying with ion-exchanged water was repeated to confirm that the constant weight was obtained. The weight of the glass filter was subtracted from this weight to obtain a fine weight. The fine content is the fine weight / sieve total resin weight.

(11) Measurement of the melting peak temperature of pine (hereinafter referred to as "melting point of pine")

Measured using a differential scanning calorimeter (DSC) manufactured by Seiko Denshi Kogyo Co., Ltd., RDC-220. In (10), the fine collected from 20 kg of polyester was dried under reduced pressure at 25 ° C. for 3 days, and DSC measurements were carried out at a temperature increase rate of 20 ° C./min using a sample of 4 mg for one measurement from this, and the melting peak. The melting peak temperature on the hottest side of the temperature is obtained. The measurement is performed on up to 10 samples, and the average value of the melting peak temperature on the hottest side is obtained. If there is only one melting peak, the temperature is obtained.

(12) Crystallization temperature (Tc1) at the time of temperature rise of a molded object, and crystallization temperature (Tc2) at the time of temperature fall

It is measured with a differential thermal analyzer (DSC) manufactured by Seiko Denshi Kogyo Co., Ltd., RDC-220. 10 mg of sample from the 2 mm-thick plate center part of the molded board of following (15) was used. It heated up at the temperature increase rate of 20 degree-C / min, hold | maintained at 290 degreeC for 3 minutes, and then, it lowered from 290 degreeC to 240 degreeC at 10 degreeC / min, and further reduced 240 degreeC to 130 degreeC at 7 degree-C / min. . The peak temperature of the crystallization leak observed at elevated temperature is referred to as the crystallization temperature Tc1 at elevated temperature and the peak temperature of the crystallization peak observed at elevated temperature is referred to as crystallization temperature Tc2 at elevated temperature.

(13) Haze (% cloudiness) and haze nonuniformity

The sample is cut out from the molded object (thickness 5mm) of following (15), and it measures by the haze meter made by Nippon Denshoku Co., Ltd., model NDH 2000. In addition, the haze of the molded board (thickness 5mm) shape | molded continuously 50 times was measured, and haze nonuniformity was calculated | required by the following.

Haze nonuniformity = maximum of haze / minimum of haze

In addition, the haze of the extending | stretching hollow molded object cut out the sample from the bottle trunk part of following (16), and measured by the haze meter made by Nippon Denshoku Corporation, model NDH 2000.

(14) Number average molecular weight Mn, weight average molecular weight Mw, Z average molecular weight Mz and dispersion ratio Mw / Mn of molecular weight distribution and dispersion ratio Mz / Mn of molecular weight distribution

The number average molecular weight Mn, the weight average molecular weight Mw, and the Z average molecular weight Mz were determined by the GPC method. However, the number average molecular weight Mn and the weight average molecular weight Mw in the case of obtaining the dispersion ratio Mw / Mn of the molecular weight distribution are determined by the integration range 1, and the number average in the case of obtaining the dispersion ratio Mz / Mn of the molecular weight distribution. Molecular weight Mn and Z average molecular weight Mz were calculated | required by integration range 2.

(Preparation of Sample) A sample solution was prepared by dissolving 1 mg of sample in 0.2 ml of chloroform / hexafluoroisopropanol = 3/2 (vol%) and diluting with 3.8 ml of chloroform.

(Eluent) chloroform / hexafluoroisopropanol = 98/2 (vol%)

(Device) TOSOH HLC-8220GPC made from Tosoh Corporation was used.

(Column) TSKgel SuperHM-H * 2 + TSKgel SuperH2000 made by Tosoh Corporation

(Standard polystyrene) TSK standard polystyrene made from Tosoh Corporation was used.

(Measurement conditions) Measuring temperature 40 ℃, flow rate 0.6 ml / min

(Detector) UV detector 254 nm

(Molecular weight conversion) It calculated by standard styrene conversion.

(Integrated range 1) The peak start was set to 450000 with standard polystyrene.

The peak end was 250 with standard polystyrene.

(Integrated Range 2) The peak start was set to standard polystyrene to the starting point of the acid and the peak end to 700 to standard polystyrene.

Dispersion ratio Mw / Mn and dispersion ratio Mz / Mn of molecular weight distribution were calculated | required from the following.

Dispersion ratio of molecular weight distribution = Mw / Mn

Dispersion ratio of molecular weight distribution = Mz / Mn

In the case of the unstretched molded body and the stretched hollow molded body, a sample was taken from the inlet.

(15) Molding of end-bonded molding plate

The polyester which was dried under reduced pressure at 140 ° C. for about 16 hours using a pressure reduction dryer was provided with a gate portion G as shown in Figs. 1 and 2 by an injection molding machine M-150C-DM injection molding machine manufactured by Meiki Seisakusho, 2 mm-11 mm (thickness of A part = 2 mm, thickness of B part = 3 mm, thickness of C part = 4 mm, thickness of D part = 5 mm, thickness of E part = 10 mm, thickness of F part = 11 mm) The end-bonding molded plate was injection molded.

In order to prevent moisture absorption during molding using a polyester previously dried under reduced pressure using a vacuum dryer DP61 manufactured by Yamato Chemical Co., Ltd., a dry inert gas (nitrogen gas) purge was performed in the molding material hopper. As plasticization condition by M-150C-DM injection molding machine, feed screw rotation speed = 70%, screw rotation speed = 120 rpm, back pressure 0.5 MPa, cylinder temperature is 45 ℃, 250 in order from immediately below the hopper. ℃, and then set to 280 ℃ or 290 ℃ including the nozzle. In the injection condition, the injection pressure and the packing pressure were adjusted so that the injection speed and the packing pressure were 20% and the weight of the molded article was 146 ± 0.2 g, and the packing pressure was adjusted to be 0.5 MPa lower than the injection pressure.

The injection time, the holding time, and the upper limit were set to 10 seconds, 7 seconds, and the cooling time to 50 seconds, respectively, and the total cycle time including the ejection time of the molded article was about 75 seconds.

In the mold, the temperature is controlled by introducing a cooling water roll having a water temperature of 10 ° C at all times.

In addition, shaping | molding temperature means the preset temperature of a barrel including the said nozzle.

The end-bonding molded plates used for the measurement of molded plate Tc1 and molded plate Tc2 of various polyesters used in Examples and Comparative Examples are molded plates molded at 290 ° C molding temperature.

In addition, in Examples 1-3 and Comparative Example 1, the molded plate of 290 degreeC shaping | molding temperature was used for the measurement of the molded plate haze (%) and the molded plate haze nonuniformity (%) of the polyester resin in an Example and a comparative example. In the other examples and comparative examples, a molded plate having a molding temperature of 280 ° C was used. The test plate for molded product characteristic evaluation was chosen arbitrarily from the stable molded article of the 11th-18th shot from the start of molding, after introducing a molding material and performing resin substitution. 2 mm thick plate (part A of FIG. 1) measures crystallization temperature (Tc1) at elevated temperature and crystallization temperature (Tc2) at low temperature, and 5 mm thick plate (part D of FIG. 1) is haze (cloudy%) ) Used for measurement.

(16) forming the blow molded body

1) Forming of Preform

In order to prevent the moisture absorption of a chip during shaping | molding using the polyester chip previously dried under reduced pressure using the vacuum dryer DP63 type | mold by Yamato Chemical Co., Ltd., the drying inert gas (nitrogen gas) purge in the molding material hopper was performed.

As plasticization conditions by the M-150C-DM injection molding machine made by Meiki Seisakusho, feed screw rotation speed = 70%, screw rotation speed = 120 rpm, back pressure 0.5 MPa, weighing position 50 mm, the cylinder temperature from just below the hopper The molten resin temperature was set to 280 ° C or 290 ° C, including 45 ° C, 250 ° C, and subsequent nozzles in that order. In the injection conditions, the injection pressure and the packing pressure were adjusted to 10% and the molding weight was 58.6 ± 0.2 g, and the packing pressure was adjusted to be 0.5 MPa lower than the injection pressure. The cooling time is set to 20 seconds, and the total cycle time including the molded article takeout time is approximately 42 seconds. The size of the preform is 29.4 mm in outer diameter, 145.5 mm in length, and about 3.7 mm in thickness. In the mold, the temperature is controlled by introducing a cooling water having a water temperature of 18 ° C at all times, and the mold surface temperature at the time of molding stability is around 29 ° C. The preform for characteristic evaluation was chosen arbitrarily from the stable molded article of the 20-50 shot from a start of shaping | molding after introducing a molding material and performing resin substitution.

2) Molding of stretch blow molded bodies (bottles)

The oral cavity of the preform was heated and crystallized by a homemade oral crystallization apparatus. Subsequently, this preform was blown biaxially at a magnification of about 2.5 times in the longitudinal direction and about 3.8 times in the circumferential direction with an LB-01E molding machine manufactured by CORPOPLAST, followed by heat setting for 7 seconds in the mold set at about 145 ° C. And a container having a capacity of 1500 cc (body thickness 0.45 mm) was molded. The extending | stretching temperature was adjusted to 100 degreeC, and shall be arbitrarily selected from the stable molded article of the 10-30 shot from the start of shaping | molding. A sample was taken from the inlet of the bottle, and the measurement of acetaldehyde content (AA content), cyclic trimer content (CT content), number average molecular weight (Mn), weight average molecular weight (Mw), Z average molecular weight (Mz) and dispersion ratio It used for the measurement of glass EG content and glass DEG content.

(17) measuring the strength of the bottle

The trunk of the bottle formed by the above method was cut into a large cutter, punched with a super dumbbell cutter type SDMK-1000D Dumbbell Co., Ltd. (according to JISK-7162-5A), and tensile tester SS-207D-U (Toyo Baldwin) (Manufactured) was used to measure the strength.

(18) Appearance of the blow molded body

The 20 hollow molded bodies were visually observed from the 10th start of molding in (16), and evaluated as follows.

◎: Transparent and no appearance problem

(Triangle | delta): There exists a little whitening flow shape or white matter in a hollow molded object.

×: white flow or whitening in the hollow molded body

(19) Shape and dimensions of oral portion of unstretched molded body for blow molded body

The shape and dimensions of the unstretched molded orb mouthpiece crystallized in the above (16) were visually observed and evaluated as follows.

(Double-circle): Very stable dimensional precision was obtained.

(Circle): Stable dimensional precision was obtained.

X: Insufficient crystallization, poor shape, or excessive crystallization and poor dimension.

(20) Glycol content of glass of polyester (Hereinafter, free ethylene glycol content is "free EG content", free diethylene glycol content is called "free DEG content")

Approximately 1.000 g of the sample is accurately weighed and dissolved in 8 mL of a hexafluoroisopropanol / chloroform (2/3) mixed solvent in an Erlenmeyer flask, and then 3 mL of distilled water is added to homogenize the contents. The mixed solvent is distilled off, and the residual aqueous phase is filtered using a glass fiber filter. The filtrate was applied to 10 mL with water and quantified by gas chromatography.

(21) Sodium content, magnesium content, calcium content and silicon content in chip cooling water or in water treatment water

Chip cooling water and the like were collected and filtered through a 1G1 glass filter manufactured by Iwaki Glass Co., Ltd., and the filtrate was measured by a Shimadzu Seisakusho inductively coupled plasma emission spectrometer.

(Polyester 1)

High-purity terephthalic acid and ethyl glycol were continuously supplied to the first esterification reactor containing the reactants in advance, and the reaction was carried out at about 250 ° C. and 0.5 kg / cm 2 G for 3 hours with an average residence time. In addition, crystalline germanium dioxide was dissolved in water, and the catalyst solution and ethylene glycol solution of phosphoric acid, which were heat-treated by adding ethylene glycol thereto, were separately supplied to this first esterification reactor continuously. This reactant was sent to a second esterification reactor, and the reaction was carried out to a predetermined degree of reaction at about 260 ° C. and 0.05 kg / cm 2 G under stirring. The esterification reaction product was continuously sent to the first polymerization reactor, under stirring, for 1 hour at about 265 ° C. and 25 torr, followed by stirring in the second polymerization reactor for 1 hour at about 265 ° C. and 3 torr, further It stirred in 3 polymerization reactors, and it superposed | polymerized at about 275 degreeC and 0.5-1 torr for 1 hour. The number average molecular weight of the obtained PET was 13000, and the intrinsic viscosity (IV) was 0.53.

The resin was subsequently crystallized at about 155 ° C. under a nitrogen atmosphere, further preheated to about 200 ° C. under a nitrogen atmosphere, and then sent to a continuous solid phase polymerization reactor for solid phase polymerization at about 205 ° C. under a nitrogen atmosphere. After solid-phase polymerization, the fine powder was removed by successive treatments in a four step process and a fine removal process.

The intrinsic viscosity of the obtained PET was 0.70 dl / g, the number average molecular weight was 20000, the dispersion ratio 2.6, the content of the cyclic trimer was 0.32 wt%, and the density was 1.400 g / cm 3 (crystallization degree 56.3%).

For the water treatment of the PET chip, using the apparatus shown in FIG. 3, the raw material chip supply port 1 in the upper portion of the treatment tank, the overflow outlet 2 located at the upper limit level of the treated water in the treatment tank, and the aromatic poly in the treatment tank lower portion. Treatment via the outlet 3 of the ester chip and the treated water mixture, the treated water discharged from the overflow outlet, the treated water discharged from the treatment tank, and the water draining device 4 discharged from the outlet of the lower portion of the treatment tank. The pipe 6 to which the filter medium is again sent to the water treatment tank via the fine powder removing device 5, which is a continuous filter of 30 µm made of paper, and the inlet port 7 of the processed water having been removed therefrom. , A column treatment tank having an inner volume of about 320 liters provided with an adsorption tower 8 for adsorption treatment of acetaldehyde in the finely water removed, and an inlet 9 for fresh ion-exchanged water.

The treatment water temperature was adjusted to 95 ° C. and treated at a rate of 50 kg / hour from the feed port 1 at the upper part of the treatment tank, and treated in 4 hours using the treated water having a fine powder content of about 130 ppm. From the outlet 3 in the lower part of the tank, it was continuously withdrawn with treated water at a rate of 50 kg / hour as a PET chip. Acetaldehyde (AA) content of obtained PET was 3 ppm, and cyclic trimer (CT) content was 0.32 weight%. Table 1 shows the properties of the obtained PET.

(Polyester 2)

High-purity terephthalic acid and ethyl glycol were continuously supplied to the first esterification reactor containing the reactant in advance, and the reaction was carried out at about 250 ° C. and 0.5 kg / cm 2 G for 3 hours with an average residence time. In addition, crystalline germanium dioxide was dissolved in water, and the catalyst solution and ethylene glycol solution of phosphoric acid, which were heat-treated by adding ethylene glycol thereto, were separately supplied to this first esterification reactor continuously. This reactant was sent to a second esterification reactor, and the reaction was carried out to a predetermined degree of reaction at about 260 ° C. and 0.05 kg / cm 2 G under stirring. The esterification reaction product was continuously sent to the first polymerization reactor, under stirring, for 1 hour at about 265 ° C. and 25 torr, followed by stirring in the second polymerization reactor for 1 hour at about 265 ° C. and 3 torr, further It stirred in 3 polymerization reactors, and it superposed | polymerized at about 275 degreeC and 0.5-1 torr for 1 hour. The number average molecular weight of the obtained PET was 13000, and the intrinsic viscosity (IV) was 0.53.

The resin was subsequently crystallized at about 155 ° C. under a nitrogen atmosphere, further preheated to about 200 ° C. under a nitrogen atmosphere, and then sent to a continuous solid phase polymerization reactor for solid phase polymerization at about 205 ° C. under a nitrogen atmosphere. After solid-phase polymerization, the fine powder was removed by successive treatments in a four step process and a fine removal process.

The intrinsic viscosity of the obtained PET resin was 0.85 dl / g, the number average molecular weight was 26000, the dispersion ratio 2.6, the content of the cyclic trimer was 0.30 wt%, and the density was 1.400 g / cm 3 (crystallinity 56.3%).

The water treatment of the PET chip was carried out under almost the same conditions using the same apparatus as above.

Acetaldehyde (AA) content of obtained PET was 3 ppm, and cyclic trimer (CT) content was 0.30 weight%. Table 1 shows the properties of the obtained PET.

(Polyester 3, 4)

Polyesters 3 and 4 were synthesized in the same manner as in the above method except that the solid phase polymerization time was changed. The results are shown in Table 1.

[Table 1] Properties of Used Polyester

Polyester 1 Polyester 2 Polyester 3 Polyester 4 Intrinsic viscosity (도 / g) 0.70 0.85 0.75 0.90 Number average molecular weight (Mn) 20000 26000 22000 29000 Dispersion Ratio Mw / Mn 2.60 2.60 2.50 2.30 DEG amount (mol%) 2.6 2.6 2.6 2.6 AA amount (ppm) 3 3 3 3 CT amount (% by weight) 0.32 0.30 0.30 0.25 Molding plate Tc1 (℃) 163 170 168 173 Molding plate Tc2 (℃) 180 175 177 175

Note: Values of molded plates molded at molding temperatures Tc1 and Tc2 = 290 ° C

(Polyester 5)

In the same manner as in Polyester 1, melt polycondensation and solid phase polymerization were performed to obtain Polyester 5.

As the cooling water at the time of chipping the molten polycondensation polymer, ion exchange water having a sodium content of 0.1 ppm, a calcium content of about 0.2 ppm, a magnesium content of about 0.04 ppm and a silicon content of about 0.6 ppm was used.

The ultimate viscosity of the obtained PET was 0.70 dl / g, the acetaldehyde (AA) content was 3.4 ppm, the content of the cyclic trimer was 0.34% by weight, the free ethylene glycol content was 20 ppm, the free diethylene glycol content was 8 ppm, and chip shape. Silver ellipsoidal phase with chip average weight (W) of 24.7 mg, chip crystallinity of 56.3%, sodium content of 0.03 ppm, calcium content of 0.05 ppm, silicon content of 0.6 ppm, and fine content of approximately 50 ppm And the fine melting point was 250 ° C. The properties of the obtained PET are shown in Table 2.

(Polyester 6, 7)

Polyester 6 and 7 were obtained by making it react like polyester 5 except changing polycondensation catalyst addition amount and solid-phase polymerization time. The properties of the obtained PET are shown in Table 2. Sodium content, calcium content, and silicon content were about the same as that of polyester5.

(Polyester 8)

In the case of chipping, water having a sodium content of about 10.0 ppm, a calcium content of about 12.3 ppm, a magnesium content of about 5.9 ppm, and a silicon content of 12.0 ppm is used, and the fine removal process is omitted. To melt polycondensation and solid phase polymerization to obtain polyester 8.

The properties of the obtained PET are shown in Table 2. The fine content was about 900 ppm, the sodium content was 5.1 ppm, the calcium content was 5.6 ppm, and the silicon content was 6.5 ppm.

(Polyester 9, 10)

Polyester 9, 10 was obtained like polyester 5 except having changed chip average weight (W) as Table 2 and changing solid-phase polymerization time.

The properties of the obtained PET are shown in Table 2. Sodium content, calcium content, and silicon content were about the same as polyester 1.

(Polyester 11)

A prepolymer was obtained by melt polycondensing in the same manner as in Polyester 5 except that the amount of polycondensation catalyst added was changed. After the obtained prepolymer was removed, the solid was polymerized at 213 ° C. after crystallization at 70 to 160 ° C. under reduced pressure while rotating in a rotary vacuum solid state polymerization apparatus. After solid phase polymerization, the removal process of pine etc. was performed in the quarter process. The properties of the obtained PET are shown in Table 2. Sodium content, calcium content, and silicon content were about the same as that of polyester5.

(Polyester 12)

Polyester 12 was obtained like polyester 5 except having extended melt polycondensation time to IV = 0.61 dl / g, and shortening solid-state polymerization time.

The properties of the obtained PET are shown in Table 2. Sodium content, calcium content, and silicon content were about the same as that of polyester5.

(Polyester 13, 14)

In the case of chipping, the same cooling water is used as polyester 5 or polyester 6, except that water having a sodium content of about 11.9 ppm, calcium content of about 10.3 ppm, and silicon content of 15.0 ppm is used, and the quadrant process and the fine removal process are omitted. To melt polycondensation and solid phase polymerization, to obtain polyesters 13 and 14. Table 3 shows the properties of the obtained PET. In addition, sodium content, calcium content, and silicon content were content about the same as or more than polyester 8.

(Polyester 15, 16)

As a polycondensation catalyst, it is the same as polyester 5 or polyester 6 except using the ethylene glycol solution of basic aluminum acetate, the ethylene glycol solution which previously heat-treated Irganox 1222 (made by Ciba Specialty Chemicals) and ethylene glycol. It was made to react and polyester 15 and 16 were obtained.

Table 3 shows the properties of the obtained PET. Sodium content, calcium content, and silicon content were about the same as that of polyester5.

(Polyester 17, 18)

As a polycondensation catalyst, except having used the ethylene glycol solution of titanium tetrabutoxide and the ethylene glycol solution of magnesium acetate tetrahydrate, it carried out similarly to polyester 5 or polyester 6, and obtained polyester 17 and 18.

The properties of the obtained PET are shown in Table 2. Sodium content, calcium content, and silicon content were about the same as that of polyester5.

(Polyester 19, 20)

As the polycondensation catalyst, except that an ethylene glycol solution of antimony trioxide and an ethylene glycol solution of magnesium acetate tetrahydrate were used, the reaction was carried out in the same manner as in Polyester 1 or Polyester 2 to obtain polyesters 19 and 20.

Table 3 shows the properties of the obtained PET. Sodium content, calcium content, and silicon content were about the same as that of polyester5.

(Polyester 21)

The above-mentioned polyester 5 is continuously treated from the supply port 1 of the upper part of the treatment tank at a rate of 50 kg / hour by the following water treatment tank in which the treated water temperature is adjusted to 95 ° C., followed by water treatment, and the outlet port 3 of the lower treatment tank. Was continuously drawn out with the treated water at a rate of 50 kg / hour as a PET chip. In the introduced water collected immediately before the ion exchange water inlet 9 of the water treatment device, the particle content having a particle size of 1 to 25 μm was about 1000/10 mL, the sodium content was 0.04 ppm, the magnesium content was 0.05 ppm, and the calcium content was The number of particles having a particle diameter of 1 to 40 µm of 0.05 ppm, silicon content of 0.12 ppm, and recycled water of recycled water after treatment with the filtration device 5 and the adsorption tower 8 was about 10000 particles / 10 mL. . After the water treatment, a fine treatment such as pine was removed in the same manner as in Example 1.

In addition, for the water treatment of a polyester chip, using the apparatus shown in FIG. 3, the raw material chip supply port 1 of a process tank upper part, the overflow discharge port 2 located in the process water upper limit level of a process tank, and the poly of a process tank lower part Treatment via the outlet 3 of the ester chip and the treated water mixture, the treated water discharged from the overflow outlet, the treated water discharged from the treatment tank, and the water draining device 4 discharged from the outlet of the lower treatment tank. The number 6 is a pipe 6 through which the filter medium is passed through the fine powder removing device 5, which is a continuous filter made of paper, into the water treatment tank, an introduction port 7 of these finely powdered waters, and a fine powder removing process. An adsorption tower (8) for adsorbing acetaldehyde in water and an introduction port (9) of fresh ion-exchanged water were used, and a columnar treatment tank having a content of about 50 m 3 was used.

The characteristic of obtained PET is the same as that of the polyester 5 of Table 3 except the cyclic trimer increase amount ((triangle | delta CT amount)) at the time of melt | dissolution being 0.15 weight%. Sodium content, calcium content, and silicon content were about the same as that of polyester5.

(Polyester 22)

Polyester 6 was water-treated in the same manner to the above, and polyester 22 was obtained.

The characteristic of the obtained PET is the same as that of the polyester 6 of Table 3 except that the cyclic trimer increase amount ((triangle | delta CT amount)) at the time of melting is 0.15 weight%. Sodium content, calcium content, and silicon content were about the same as that of polyester5.

TABLE 2

Note: Values of molded plates molded at molding temperatures Tc1 and Tc2 = 290 ° C

(Example 1)

The polyester resin obtained by blending the synthesized pellets of the polyester 1 and the polyester 2 in a ratio of 7: 3 was injection molded under the conditions of the melt resin temperature of 290 ° C and a melt residence time of 110 seconds by the method of (16). Evaluation was performed about the preform obtained and the stretched molded bottle. The results are shown in Table 3.

In addition, in the following Examples 2, 3, and Comparative Example 1, the molded plate haze is a value of a 5 mm thick plate (D in FIG. 1) obtained at a molding temperature of 290 ° C. by the method of (15).

Also,

(Examples 2 and 3)

By the composition shown in Table 3, it carried out similarly to Example 1, and evaluated the polyester resin of Examples 2 and 3. The results are shown in Table 3.

(Comparative Example 1)

The polyester resin of Comparative Example 1 was evaluated in the same manner as in Example 1 by the composition shown in Table 3, but as compared with Example 1 having the same number average molecular weight, the polyester of Comparative Example 1 ΔAA of the resin composition was high, and the bottle strength was lowered to 186 Mpa. The results are shown in Table 3.

Tables 1 to 3 and Comparative Example 1

Example Example 1 Example 2 Example 3 Comparative Example 1  Polyester One 70 80 56 - 2 30 - - - 3 30 100 4 - 20 14 -  Polyester resin Intrinsic viscosity (도 / g) 0.74 0.74 0.74 0.74 Number average molecular weight 22000 22000 22000 22000 Dispersion Ratio Mw / Mn 3.23 3.50 3.35 2.50 Dispersion Ratio Mz / Mn 3.70 3.85 3.80 3.30 ΔTc1 (° C) 7 10 10 - ΔTc2 (° C) 5 5 5 △ CT amount (wt%) 0.12 0.11 0.11 0.11  Free form Dispersion Ratio Mw / Mn 3.20 3.50 3.30 2.50 Dispersion Ratio Mz / Mn 3.40 3.65 3.45 3.20 Tc1 (° C) 165 166 167 168 Tc2 (° C) 178 177 176 173 △ AA amount (ppm) 10 9 10 16 Bottle Strength (Mpa) 198 223 210 186 Molding plate Haze 4.5 4.7 4.6 4.6

Note: Value of molded plate molded at molding temperature of molded plate haze = 290 ° C

(Example 4)

Changing the molding plate and molten resin temperature of the polyester resin obtained by blending the pellets of polyester 5 and polyester 6 in a ratio of 7: 3 at 290 ° C by the method of (15) to 280 ° C. Other than that evaluated the preform and the stretched bottle obtained by the method of (16). The results are shown in Table 3.

The shape and dimensions after the crystallization of the unstretched molded orifice are not a problem, the AA content of the stretched hollow molded body is 8.5 ppm, the content of the cyclic trimer is 0.38% by weight, the free ethylene glycol content is 25 ppm, the free diethylene glycol content is 10 It was no problem at the value which was no problem in ppm and haze 1.2%.

(Example 5)

The polyester resin of Example 5 was evaluated similarly to Example 4 by the composition shown in Table 4 using the mixture of water-treated PET. The results are shown in Table 3. All the evaluated properties were similarly good as in Example 4. In addition, the cyclic trimer increase amount (ΔCT amount) at the time of melting was also low as 0.15 weight%.

(Example 6)

Evaluation was performed similarly to Example 4 about the polyester resin composition of Example 6 which blended said polyester 1, 70 weight part, polyester 2, 30 weight part, and polyamide 1, 1 weight part. The results are shown in Table 4.

The AA content of the stretched blow molded body was as low as 5.7 ppm, good at 1.5% haze, and other characteristics were not a problem.

(Comparative Example 2)

As shown in Table 4, it evaluated similarly to Example 4 about the polyester 3 of the comparative example 2.

As apparent from the examples, the AA content and haze value of the stretched blow molded body were high, and the shape and dimensions after crystallization of the stretch blow molded body sphere were poor. The results are shown in Table 4.

(Comparative Example 3)

As shown in Table 4, the polyester resin of the comparative example 3 was evaluated.

As apparent from the examples, the haze value of the stretched blow molded body was high, and the shape and dimensions after crystallization of the stretch blow molded body sphere were poor. The results are shown in Table 4.

(Comparative Example 4)

As shown in Table 4, the polyester resin of the comparative example 4 was evaluated.

As is clear from the examples, the AA content, the free ethylene glycol content, the free diethylene glycol content, and the haze value of the stretched blow molded body were high, and the shape and dimensions after crystallization of the stretch blow molded body sphere were poor. The results are shown in Table 4.

(Comparative Example 5)

As shown in Table 4, the polyester resin of the comparative example 5 was evaluated.

As apparent from the examples, the AA content and haze value of the stretched blow molded body were high, and the shape and dimensions after crystallization of the stretch blow molded body sphere were poor. The results are shown in Table 4.

(Comparative Example 6)

As shown in Table 4, the polyester resin of the comparative example 6 was evaluated.

As apparent from the examples, the AA content and haze value of the stretched blow molded body were high, and the shape and dimensions after crystallization of the stretch blow molded body sphere were poor. The results are shown in Table 4.

(Comparative Example 7)

As shown in Table 4, the polyester resin of the comparative example 7 was evaluated.

As is clear from the examples, the AA content, the free ethylene glycol content, the free diethylene glycol content and the haze of the stretched blow molded body were high, and the shape and dimensions after crystallization of the stretched blow molded body sphere were poor. The results are shown in Table 4.

TABLE 4

    Note: DELTA Tc1, DELTA Tc2 = Difference between molded plates Tc1 or Tc2 of polyester used

W _A / W _B = average weight ratio of polyester chip

  Molded plate haze (%) / copper non-uniformity (%) = value of the molded plate molded at the molding temperature of 280 ℃

(Example 7)

By the composition shown in Table 5, it evaluated similarly to Example 4 about the polyester resin of Example 7. The results are shown in Table 5. All the evaluated properties were similarly good as in Example 4.

(Example 8)

By the composition shown in Table 5, it evaluated similarly to Example 4 about the polyester resin of Example 8. The results are shown in Table 5. All the evaluated properties were similarly good as in Example 4.

(Example 9)

By the composition shown in Table 5, the polyester resin of Example 9 was evaluated like Example 4, and it evaluated. The results are shown in Table 5. All the evaluated properties were similarly good as in Example 4.

(Comparative Example 8)

Molding evaluation was carried out in the same manner as in Example 4 except that the melt resin temperature was changed to 520 seconds using the same polyester resin as in Example 4. The shape of the preform of the preform is poor and the dimension is also outside the standard and is "x". The appearance of the stretched blow molded body is "◎", and the haze is 1.3%, but the AA content is 32.1 ppm, the glass EG content is 64 ppm, and the glass is good. The DEG content was 28 ppm and the bottle trunk strength was 180 Mpa.

TABLE 5

The present invention provides a polyester resin that provides a molded article having a low amount of aldehydes during molding and excellent molded mechanical properties such as pressure resistance when the molded article is formed because of improved flow characteristics. In addition, since the polyester resin of the present invention has improved flow characteristics, there is less warping during molding, and a molded article excellent in heat-resistance dimensional stability, in particular, a hollow molded article can be efficiently produced by high-speed molding, and furthermore, it has high pressure resistance and heat resistance dimensions. Provided are a polyester resin having very good stability and excellent in continuous moldability for a long time with little contamination of a mold, a molded article formed thereof, and a method for producing the molded article.

Claims (12)

An aromatic polyester having a repeating unit mainly composed of an aromatic dicarboxylic acid component and a glycol component, wherein the dispersion ratio Mw / Mn of the molecular weight distribution is 3.00 or more. A polyester resin comprising at least two kinds of polyesters of substantially the same composition as a main component, wherein the difference in the ultimate viscosity of the polyester is in the range of 0.05 to 0.30 dl / g, and the crystallization temperature at the time of temperature reduction of the polyester A polyester resin, wherein the difference is within 18 ° C. A polyester resin comprising the following polyesters A and B as main components comprising ethylene terephthalate as the main repeating unit, wherein the difference between the intrinsic viscosity IV _A of polyester _A and the intrinsic viscosity IV _B of polyester B is 0.05 to 0.30 And a difference between the crystallization temperature at the time of lowering of polyester A and the crystallization temperature at the time of lowering of polyester B is within 18 ° C. Polyester A: The intrinsic viscosity IV _A is 0.60 to 0.75 dl / g, the acetaldehyde content is 10 ppm or less, the crystallization temperature at elevated temperature measured by DSC is 140 to 178 캜, and the crystallization temperature at elevated temperature is 160 to 190 캜. Polyester Polyester B: The intrinsic viscosity IV _B is 0.73 to 0.90 dl / g, the acetaldehyde content is 10 ppm or less, the crystallization temperature at elevated temperature measured by DSC is 140 to 178 ° C, and the crystallization temperature at elevated temperature is 160 to 190 ° C. Polyester The polyester resin according to any one of claims 1 to 3, wherein the dispersion ratio Mz / Mn of the molecular weight distribution is 3.60 or more. The polyester resin according to any one of claims 1 to 4, wherein the cyclic trimer content is 0.50% by weight or less. The polyester resin according to any one of claims 1 to 5, wherein the amount of cyclic ester oligomer increase when molten for 60 minutes at a temperature of 290 ° C is 0.50% by weight or less. The polyester resin according to any one of claims 1 to 6, which contains 0.1 to 5000 ppm of fine particles of polyester having the same composition as the polyester. The polyester resin composition of any one of Claims 1-7 which mix | blended 0.1 ppb-50000 ppm of at least 1 sort (s) of resin chosen from the group which consists of a polyolefin resin and a polyacetal resin. The polyester resin according to any one of claims 1 to 8 is kneaded and molded under the condition that the melt resin temperature in the molding machine is 260 to 295 ° C and the melt residence time in the molding machine is 10 to 500 seconds. Method for producing a polyester unstretched molded article. The polyester unstretched molded object obtained by the manufacturing method of claim 9 is stretched in at least one direction, The manufacturing method of the polyester stretched molded object characterized by the above-mentioned. The dispersion molded product Mw / Mn of molecular weight distribution is 3.00 or more, The polyester molded object characterized by the above-mentioned. Dispersion ratio Mz / Mn of molecular weight distribution is 3.30 or more, The polyester molded object characterized by the above-mentioned.

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