JP2003192882A - Polyester resin composition and polyester molded product obtained therefrom - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a polyester composition excellent in a crystallization control property in melt molding and a long-term continuous moldability and a blow molded product, a sheet-like material and an oriented film each obtained from the composition and each excellent in transparency and dimensional stability to heat. <P>SOLUTION: This polyester composition is composed of a PET obtained by solid phase polymerization and 0.1 ppb to 50,000 ppm at least one kind of resin selected from a group consisting of a polyolefin resin, a polyamide resin and a polyacetal resin. In the chip of the polyester, area intensity ratio As on the chip surface of an absorption band in IR derived from a trans structure formed by internal rotation using C-C bond of EG unit as an axis to an absorption band derived from a gauche structure and a ratio As/Ac of the area intensity ratio As to an area intensity ratio Ac in the center part of the chip are each within a specific range. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polyester composition and a molded article formed from the same, and more particularly to a polyester composition excellent in crystallization controllability during melt molding and long-term continuous moldability, and transparency and heat resistance. The present invention relates to a hollow molded article having excellent dimensional stability, a sheet-like material, and a stretched film.

[0002]

2. Description of the Related Art A polyester whose main repeating unit is ethylene terephthalate (hereinafter sometimes abbreviated as PET resin) is a carbonated beverage due to its excellent transparency, mechanical strength, heat resistance, gas barrier property and the like. It has been used as a material for containers such as juice, juice and mineral water, and its spread is remarkable. In these applications, polyester bottles are hot-filled with a beverage that has been sterilized at high temperature, or the beverage is sterilized at high temperature after filling, but with a normal polyester bottle, shrinkage occurs during such heat-filling treatment. Deformation occurs and becomes a problem. As a method for improving the heat resistance of a polyester bottle, a method has been proposed in which the bottle mouth plug is heat-treated to increase the crystallinity, or the stretched bottle is heat-fixed.
In particular, when the crystallization of the spout is insufficient or the crystallization degree varies greatly, the sealing property with the cap may be deteriorated and the contents may leak.

Further, in order to improve the heat resistance of the bottle body, a method is adopted in which the temperature of the stretching blow mold is raised to a high temperature (for example, see Patent Document 1). In the case of bottles used for heat sterilization at high temperatures,
When a PET resin having a high crystallization rate is used, only a heat-treated bottle having poor transparency and having a large variation in crystallinity of the plug portion can be obtained. In particular, when a defective product generated in a molding factory or a recovered product of a used bottle is reused as a part of a bottle molding material, the crystallization property of the virgin raw material becomes a problem. Such a problem frequently occurs in a large-sized bottle having a capacity of 1.5 liters or more because the wall thickness becomes large.

Further, when a large number of bottles are molded by using the same mold by such a method, the bottles obtained with long-time operation are whitened and the transparency is lowered, and only bottles having no commercial value are obtained. You won't get it. It was found that this is because deposits due to the PET resin were attached to the mold surface, resulting in mold stains, which were transferred to the surface of the bottle. In particular, in recent years, the molding speed has been increased for the purpose of reducing the cost at the time of bottle production, and the mold contamination has become a greater problem from the viewpoint of productivity.

Further, in the case of a content liquid that needs to be hot-filled, such as a fruit juice drink, a method of heat-treating the mouth part of a preformed or molded bottle to crystallize it (for example, Patent Document 2, Patent Document 3) is general. In such a method, that is, a method of heat-treating the plug portion and the shoulder portion to improve heat resistance, the time and temperature of the crystallization treatment greatly affect the productivity, and the treatment can be performed at a low temperature in a short time. It is preferable that the PET resin has a high conversion rate. On the other hand, the body is required to be transparent even when subjected to heat treatment during molding so that the color tone of the filling is not deteriorated, and the spout and the body need to have contradictory properties.

Various proposals have been made to solve such problems. For example, a method of adding an inorganic nucleating agent such as kaolin or talc to polyethylene terephthalate (see, for example, Patent Documents 4 and 5), a method of adding an organic nucleating agent such as montanic acid wax salt (for example, Patent Document 6, Patent Document 7), but these methods have problems in practical use due to the generation of foreign matter and cloudiness. Further, a method of inserting a heat-resistant resin piece into the spout part has been proposed (see, for example, Patent Documents 8 and 9), but the bottle productivity is poor and there is a problem in recyclability. .

[0007] To solve the problem of mold contamination, a method has been conventionally used to reduce the cyclic trimer, which is the main component of the deposit on the mold surface, by solid-phase polymerizing the PET resin in advance. However, this method is insufficient in its effect because the cyclic trimer is regenerated during remelting and parison molding. Also disclosed is a method in which a polyester resin is treated with water at 90 to 110 ° C. to suppress the activity of the catalyst and control the formation of a cyclic trimer during parison molding (see, for example, Patent Document 10). However, this method requires special equipment and processing time for the treatment,
There is a problem that the manufacturing process becomes complicated. In addition, although the mold stain is reduced by the above method, it is still insufficient, and in some cases, a sufficient effect may not be obtained, and the transparency of the obtained molded body may be insufficient. there were.

[0008]

[Patent Document 1] Japanese Patent Publication No. 59-6216

[Patent Document 2] Japanese Patent Laid-Open No. 55-79237

[Patent Document 3] Japanese Patent Laid-Open No. 58-110221

[Patent Document 4] Japanese Patent Application Laid-Open No. 56-2342

[Patent Document 5] JP-A-56-21832

[Patent Document 6] Japanese Patent Laid-Open No. 57-125246

[Patent Document 7] Japanese Unexamined Patent Publication No. 57-207639

[Patent Document 8] Japanese Patent Laid-Open No. 61-259946

[Patent Document 9] Japanese Patent Application Laid-Open No. 2-269638

[Patent Document 10] Japanese Patent Publication No. 3-47830

[0009]

DISCLOSURE OF THE INVENTION The present invention solves the problems of the above-mentioned conventional polyesters, and the crystallization of the plug portion occurs rapidly, and the shrinkage rate of the plug portion falls within an appropriate range. The purpose is to provide a polyester composition that gives a molded article having high speed and excellent transparency, and further, a polyester that does not pollute the mold more than a conventional catalyst deactivating resin by water treatment. It is intended to provide a composition.

[0010]

In order to achieve the above object, the polyester composition of the present invention comprises a solid-phase polymerized polyester whose main repeating unit is ethylene terephthalate, a polyolefin resin, a polyamide resin, and a polyacetal. A polyester composition comprising 0.1 ppb to 50,000 ppm of at least one resin selected from the group consisting of resins, wherein the polyester chip has a carbon-carbon bond of an ethylene glycol unit in an infrared absorption spectrum as an axis. And the area intensity ratio As (T / G) on the chip surface of the absorption band (T) derived from the trans structure and the absorption band (G) derived from the gosh structure generated by the internal rotation As (T / G)
The ratio As (T / G) / Ac (T / G) between the area intensity ratio Ac (T / G) at the center of the chip is expressed by the following formula (1):
A polyester composition which is a chip satisfying (2).

4.00 ≤ As (T / G) ≤ 9.00 (1) 0.60 ≤ As (T / G) / Ac (T / G) ≤ 0.99 (2) (In the above formula, As (T / G) is an absorption band (T) derived from a trans structure and an absorption band derived from a gosh structure generated by internal rotation around the carbon-carbon bond of the ethylene glycol unit in the infrared absorption spectrum. (G) shows the area intensity ratio on the chip surface, and Ac (T / G) is derived from a trans structure generated by internal rotation around the carbon-carbon bond of the ethylene glycol unit in the infrared absorption spectrum. Absorption band (T)
And the area intensity ratio of the absorption band (G) derived from the gosh structure at the center of the chip. )

By melt-molding the polyester composition of the present invention having the above-mentioned constitution, a molded article having excellent transparency and heat-resistant dimensional stability, particularly a hollow molded article such as a container, can be easily obtained. it can. That is, the present invention can give a molded article having excellent transparency, which has a crystallization rate in which the plug portion crystallization of the hollow molded body occurs rapidly and the contraction rate of the plug portion is in an appropriate range. The present invention provides a possible polyester composition.

Here, in the infrared absorption spectrum, an absorption band (T) derived from a trans structure and an absorption band derived from a gosh structure (T) generated by internal rotation about a carbon-carbon bond of an ethylene glycol unit as an axis. G), the area intensity ratio As (T / G) on the chip surface, the area intensity ratio Ac (T / G) at the center of the chip, and the ratio As (T / G) / Ac (T / G) are described later. Can be obtained by the method.

In this case, the fine content of the polyester having the same composition as that of the polyester is 0.1 to 10.
It can be 5000 ppm.

In this case, the content of the film-like material having the same composition as the polyester may be 10 ppm or less.

Further, here, fine means JIS-Z8.
801 means a fine polyester powder that has passed through a sieve having a wire mesh of nominal size 1.7 mm, and a film-like material means a nominal size 5.6 mm according to JIS-Z8801.
2 of the polyester remaining on the wire mesh sieve
It means a film-like material after the chip-like material in which one or more chips are fused or cut into pieces larger than the normal shape is removed, and the content thereof is measured by the following measuring method.

In this case, the peak temperature on the highest side of the fine melting peak temperature may be 265 ° C. or lower.

The fine melting point is measured by a differential scanning calorimeter (DSC) according to the method described below. The melting peak temperature of DSC is called the melting point. The melting peak representing this melting point is composed of one or more melting peaks. In the present invention, when there is one melting peak, the peak temperature and the melting peak are determined. -In the case of a plurality of melting peaks, the melting peak temperature on the highest temperature side among these plural melting peaks is defined as "the peak temperature on the highest temperature side of the fine melting peak temperature". In the examples and the like, it is referred to as “fine melting point”.

In this case, the polyester is
In the chip forming step after the melt polycondensation, the sodium content (N), the magnesium content (M), the silicon content (S) and the calcium content (C) are the following (3).
The polyester may be chipped with cooling water satisfying at least one of (6) to (6). N ≤ 1.0 (ppm) (3) M ≤ 0.5 (ppm) (4) S ≤ 2.0 (ppm) (5) C ≤ 1.0 (ppm) (6)

In this case, at a temperature of 290 ° C., 60
0.50% by weight of cyclic trimer when melted for 1 minute
It can be:

In this case, the molded article may be formed by molding the polyester composition described above.

Further, in this case, the molded product of the polyester composition may be any of a hollow molded product, a sheet-shaped product and a stretched film stretched in at least one direction.

The above-described polyester composition of the present invention is less likely to cause mold stains during molding, has excellent crystallization controllability of the spout, and has excellent transparency, heat resistance, mechanical properties, and residual properties. A hollow molded article, a sheet-like material and a stretched film having little off-taste and off-flavor and excellent in aroma retention are provided.

[0024]

BEST MODE FOR CARRYING OUT THE INVENTION The embodiments of the polyester composition of the present invention, and the hollow molded article, sheet-like material and stretched film comprising the same will be specifically described below. The polyester according to the present invention is a polyester whose main repeating unit is ethylene terephthalate, preferably a linear polyester containing 85 mol% or more of ethylene terephthalate units, and more preferably 90 mol% or more. ,
A linear polyester containing 95% by mole or more is particularly preferable.

The dicarboxylic acid as a copolymerization component used when the polyester is a copolymer is
Aromatic dicarboxylic acids such as isophthalic acid, 2,6-naphthalenedicarboxylic acid, diphenyl-4,4'-dicarboxylic acid, diphenoxyethanedicarboxylic acid and functional derivatives thereof, p-oxybenzoic acid, oxycaproic acid, etc. Oxyacids and their functional derivatives, adipic acid, sebacic acid, succinic acid, glutaric acid and other aliphatic dicarboxylic acids and their functional derivatives, cyclohexanedicarboxylic acid and other aliphatic dicarboxylic acids and their functional derivatives, etc. .

When the polyester is a copolymer, the glycol used as a copolymerization component includes diethylene glycol, trimethylene glycol, tetramethylene glycol, neopentyl glycol and the like. Aliphatic glycols, alicyclic glycols such as cyclohexane dimethanol, bisphenol A, aromatic glycols such as alkylene oxide adducts of bisphenol A and the like can be mentioned.

Further, as the polyfunctional compound as a copolymerization component used when the polyester is a copolymer, examples of the acid component include trimellitic acid and pyromellitic acid. Examples of the component include glycerin and pentaerythritol. The amount of the above copolymerization component used should be such that the polyester maintains a substantially linear shape. Further, a monofunctional compound such as benzoic acid or naphthoic acid may be copolymerized.

The above-mentioned polyester is obtained by directly reacting terephthalic acid with ethylene glycol and, if necessary, the above-mentioned copolymerization component to distill off water to esterify it, and then use Sb compound, Ge compound, Al as a polycondensation catalyst. Compound or T
Direct esterification method in which polycondensation is carried out under reduced pressure using one or more compounds selected from i compounds, or dimethyl terephthalate and ethylene glycol and, if necessary, the above copolymerization components are present in the presence of an ester exchange catalyst. After reacting under the conditions to distill off methyl alcohol and transesterify, one or more compounds selected from Sb compounds, Ge compounds, Al compounds or Ti compounds are used as polycondensation catalysts to reduce the pressure. It is produced by a transesterification method in which polycondensation is performed below.

As the starting material dimethyl terephthalate, terephthalic acid or ethylene glycol,
Virgin dimethyl terephthalate derived from paraxylene, terephthalic acid or ethylene glycol derived from ethylene, as well as dimethyl terephthalate and terephthalic acid recovered from used PET bottles by a chemical recycling method such as methanol decomposition or ethylene glycol decomposition. A recovered raw material such as bishydroxyethyl terephthalate or ethylene glycol can also be used as at least a part of the starting material. The quality of the recovered raw material is a purity according to the purpose of use,
It goes without saying that it must be refined to quality.

As the Ge compound, amorphous germanium dioxide, crystalline germanium dioxide powder or a slurry of ethylene glycol, a solution of crystalline germanium dioxide dissolved in water by heating, or ethylene glycol added thereto and heat treated Although a solution or the like is used, in particular, in order to obtain the polyester used in the present invention, it is preferable to use a solution in which germanium dioxide is heated and dissolved in water, or a solution in which ethylene glycol is added and heated. In addition to these, compounds such as germanium chloride, germanium tetraethoxide, germanium tetra-n-butoxide, and germanium phosphite may be mentioned. When using a Ge compound, the amount used is G in the polyester resin.
e Remaining amount of 10 to 150 ppm, preferably 13 to
It is 100 ppm, more preferably 15 to 70 ppm.

As the Ti compound, tetraalkyl titanate such as tetraethyl titanate, tetraisopropyl titanate, tetra-n-propyl titanate and tetra-n-butyl titanate and their partial hydrolysis are used. Examples thereof include titanyl oxalate, titanyl ammonium oxalate, sodium titanyl oxalate, potassium titanyl oxalate, titanyl calcium oxalate, titanyl oxalate compounds such as strontium titanyl oxalate, trimellitic acid titanium, titanium sulfate, titanium chloride and the like. The Ti compound is a formed polymer.
It is added so that the remaining amount of Ti in it is in the range of 0.1 to 10 ppm.

As the Sb compound, antimony trioxide,
Antimony acetate, antimony tartrate, potassium antimony tartrate, antimony oxychloride, antimony glycolate
, Antimony pentoxide, triphenylantimony, and the like. The Sb compound is added so that the amount of Sb remaining in the produced polymer is in the range of 50 to 250 ppm.

As the Al compound, specifically,
Aluminum formate, aluminum acetate, basic aluminum acetate, aluminum propionate, aluminum oxalate, aluminum acrylate, aluminum laurate, aluminum stearate, aluminum benzoate, aluminum trichloroacetate, aluminum lactate,
Carboxylates such as aluminum citrate and aluminum salicylate, aluminum chloride, aluminum hydroxide, aluminum hydroxide chloride, polyaluminum chloride,
Inorganic acid salts such as aluminum nitrate, aluminum sulfate, aluminum carbonate, aluminum phosphate, aluminum phosphonate, aluminum methoxide, aluminum ethoxide, aluminum n-propoxide, aluminum iso-propoxide, aluminum n-butoxide, aluminum t-butoxide, etc. Aluminum chelate compounds such as aluminum alkoxide, aluminum acetylacetonate, aluminum acetylacetate, aluminum ethylacetoacetate, aluminum ethylacetoacetate diiso-propoxide, trimethylaluminum, triethylaluminum and other organoaluminum compounds and their partial hydrolysates. , Aluminum oxide and the like. Among these, carboxylates, inorganic acid salts and chelate compounds are preferable, and among these, basic aluminum acetate, aluminum chloride, aluminum hydroxide, aluminum hydroxide chloride and aluminum acetylacetonate are particularly preferable. The Al compound is added so that the amount of Al remaining in the produced polymer is in the range of 5 to 200 ppm.

In the method for producing a polyester according to the present invention, an alkali metal compound or an alkaline earth metal compound may be used in combination. Examples of alkali metals and alkaline earth metals are Li, Na, K, Rb, Cs, and B.
At least one selected from e, Mg, Ca, Sr, and Ba is preferable, and the use of an alkali metal or a compound thereof is more preferable. When using an alkali metal or a compound thereof, use of Li, Na and K is particularly preferable. Examples of compounds of alkali metals and alkaline earth metals include formic acid, acetic acid, propionic acid, and the like of these metals.
Saturated aliphatic carboxylates such as butyric acid and oxalic acid, unsaturated aliphatic carboxylates such as acrylic acid and methacrylic acid, aromatic carboxylates such as benzoic acid, halogen-containing carboxylates such as trichloroacetic acid, lactic acid, and citrate. Acid, hydroxycarboxylic acid salts such as salicylic acid, carbonic acid, sulfuric acid, nitric acid, phosphoric acid, phosphonic acid, hydrogen carbonate, hydrogen phosphate, hydrogen sulfide, sulfurous acid, thiosulfuric acid, hydrochloric acid, hydrobromic acid, chloric acid,
Inorganic acid salts such as bromic acid, 1-propanesulfonic acid, 1-
Organic sulfonates such as pentane sulfonic acid and naphthalene sulfonic acid, organic sulfates such as lauryl sulfate, methoxy, ethoxy, n-propoxy, iso-propoxy,
Examples thereof include alkoxides such as n-butoxy and tert-butoxy, chelate compounds with acetylacetonate, hydrides, oxides and hydroxides.

The above-mentioned 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 the alkaline earth metal compound is added so that the residual amount of these elements in the produced polymer is in the range of 1 to 50 ppm.

Further, various phosphorus compounds can be used as the stabilizer. Examples of the phosphorus compound used in the present invention include phosphoric acid, phosphorous acid, phosphonic acid and their derivatives. Specific examples thereof include phosphoric acid, phosphoric acid trimethyl ester, phosphoric acid triethyl ester, phosphoric acid tributyl ester, phosphoric acid triphenyl ester, phosphoric acid monomethyl ester, phosphoric acid dimethyl ester, phosphoric acid monobutyl ester, phosphoric acid dibutyl ester, and phosphorous acid. Phosphoric acid, phosphorous acid trimethyl ester, phosphorous acid triethyl ester, phosphorous acid tributyl ester, methylphosphonic acid, methylphosphonic acid dimethyl ester,
Examples include ethylphosphonic acid dimethyl ester, phenylphosphonic acid dimethyl ester, phenylphosphonic acid diethyl ester, and phenylphosphonic acid diphenyl ester, which may be used alone or in combination of two or more kinds. Good. The phosphorus compound is 5 to 1000 ppm, preferably 10 to 5 as the residual amount of phosphorus in the polymer.
It is in the range of 00 ppm. Such a phosphorus compound can be added at any stage of the above-mentioned polyester formation reaction step, and the above-mentioned phosphorus compound is contained in the following polyester which is subjected to contact treatment with water or polyester blended with a polyolefin resin. It can be contained by a method of mixing the above master-batch or a method of contact treatment with the above-mentioned phosphorus compound aqueous solution or organic solvent solution.

The melt polycondensed polyester obtained as described above is extruded from the pores after completion of the melt polycondensation, and is made into chips while being cooled with cooling water. Then, in order to further increase the intrinsic viscosity of the polyester and reduce the acetaldehyde content, solid-phase polymerization can be performed by a conventionally known method. The above polyester to be subjected to solid phase polymerization is pre-crystallized under an inert gas or under reduced pressure or in a steam or a steam-containing inert gas atmosphere, and then solid phase while heating in an inert gas atmosphere or under a reduced pressure. Polymerize.

The above-mentioned esterification reaction, transesterification reaction, melt polycondensation reaction and solid phase polymerization reaction may be carried out in a batch reaction apparatus or a continuous reaction apparatus. In any of these methods, the melt polycondensation reaction may be carried out in one step or may be carried out in multiple steps. The solid phase polymerization reaction can be carried out by a batch type apparatus or a continuous type apparatus as in the melt polycondensation reaction. The melt polycondensation and solid phase polymerization may be carried out continuously or may be carried out separately.

The polyester composition of the present invention contains at least one resin selected from the group consisting of solid-phase polymerized polyester whose main repeating unit is ethylene terephthalate, and a polyolefin resin, a polyamide resin, and a polyacetal resin. 1 ppb to 50000 ppm, wherein the polyester chip is an absorption band derived from a trans structure generated by internal rotation about a carbon-carbon bond of an ethylene glycol unit in an infrared absorption spectrum. Area intensity ratio As (T / G) on the chip surface between (T) and the absorption band (G) derived from the gosh structure, and the area intensity ratio As described above.
(T / G) and the area intensity ratio Ac (T
/ G) and a ratio As (T / G) / Ac (T / G) is a chip satisfying the following formulas (1) and (2). 4.00 ≤ As (T / G) ≤ 9.00 (1) 0.60 ≤ As (T / G) / Ac (T / G) ≤ 0.99 (2)

In the polyester resin composition of the present invention,
It is necessary to contain 0.1 ppb to 50,000 ppm of at least one resin selected from the group consisting of polyolefin resin, polyamide resin and polyacetal resin. The blending ratio of the resin used in the present invention into the polyester is 0.1 ppb to 50,000 ppm, preferably 0.3 ppb to 10,000 ppm, more preferably 0.5 ppb to 100 ppm, further preferably 1.0 ppb to 1 ppm, and particularly preferably. 1.0 ppb
~ 45 ppb is desirable. If the blending amount is less than 0.1 ppb, the crystallization rate tends to be very slow, and crystallization of the plug part of the hollow molded article will be insufficient. Therefore, if the cycle time is shortened, the plug part shrinks. The amount does not fall within the specified value range, resulting in poor capping.
The stretch heat-fixing mold for molding the heat-resistant hollow molded body is heavily contaminated, and when the transparent hollow molded body is to be obtained, the mold must be frequently cleaned. Also 50,000p
If it exceeds pm, the crystallization speed will be high and the crystallization of the plug part of the hollow molded article will tend to be excessive. Therefore, the amount of shrinkage / shrinkage of the plug part will not fall within the specified range, so capping will occur. It may become defective and the contents may leak, and the preform for a hollow molded body may be whitened, which makes normal stretching impossible. In the case of sheet-like material,
If it exceeds 50,000 ppm, the transparency will be extremely poor,
In addition, the stretchability may be poor and normal stretching may not be possible, and only a stretched film with large thickness unevenness and poor transparency may be obtained.

Examples of the polyolefin resin blended in the polyester composition of the present invention include polyethylene resin, polypropylene resin, and α-olefin resin. Further, these resins may be crystalline or amorphous.

Examples of the polyethylene resin blended in the polyester composition of the present invention include ethylene homopolymer, ethylene, and propylene, butene-1,3-methylbutene-1, pentene-1,4-methylpentene. −
1, hexene-1, octene-1, decene-1, and other α-olefins having about 2 to 20 carbon atoms, vinyl acetate,
Examples thereof include copolymers with vinyl compounds such as vinyl chloride, acrylic acid, methacrylic acid, acrylic acid esters, methacrylic acid esters, styrene and unsaturated epoxy compounds. 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, Examples thereof include ethylene-based resins such as ethylene-methacrylic acid copolymer and ethylene-ethyl acrylate copolymer.

Examples of the polypropylene resin blended in the polyester composition of the present invention include homopolymers of propylene, propylene, ethylene and butene.
1,3-methylbutene-1, pentene-1, 4-methylpentene-1, hexene-1, octene-1, decene-
Copolymers with other α-olefins having about 2 to 20 carbon atoms such as 1 and vinyl compounds such as vinyl acetate, vinyl chloride, acrylic acid, methacrylic acid, acrylic acid ester, methacrylic acid ester and styrene, or hexadiene ,
Examples thereof include copolymers with diene such as octadiene, decadiene and dicyclopentadiene. Specific examples include propylene-based resins such as propylene homopolymers (atactic, isotactic, syndiotactic polypropylene), propylene-ethylene copolymers, propylene-ethylene-butene-1 copolymers.

As the α-olefin resin blended in the polyester composition of the present invention, homopolymers of α-olefins having about 2 to 8 carbon atoms such as 4-methylpentene-1 and their α-olefins are used. And ethylene, propylene, butene-1, 3-methylbutene-1, pentene-
Examples thereof include copolymers with other α-olefins having about 2 to 20 carbon atoms such as 1, hexene-1, octene-1, and decene-1. Specifically, for example, butene-1 homopolymer, 4-methylpentene-1 homopolymer, butene-1-
Butene-1 type resins such as ethylene copolymer and butene-1-propylene copolymer, and 4-methylpentene-1 and C _2-
Examples thereof include copolymers with C ₁₈ α-olefins.

As the polyamide resin to be blended with the polyester composition of the present invention, for example, polymers of lactams such as butyrolactam, δ-valerolactam, ε-caprolactam, enantolactam and ω-laurolactam, 6-aminocapron. Acid, polymers of aminocarboxylic acids such as 11-aminoundecanoic acid and 12-aminododecanoic acid, hexamethylenediamine, nonamethylenediamine, decamethylenediamine, dodecamethylenediamine,
Undecamethylenediamine, 2,2,4- or 2,4
Aliphatic diamines such as 4-trimethylhexamethylenediamine, 1,3- or 1,4-bis (aminomethyl) cyclohexane, bis (p-aminocyclohexylmethane)
Alicyclic diamines such as, diamine units such as aromatic diamines such as m- or p-xylylenediamine, and glutaric acid,
Aliphatic dicarboxylic acids such as adipic acid, suberic acid and sebacic acid, alicyclic dicarboxylic acids such as cyclohexanedicarboxylic acid, polycondensates with dicarboxylic acid units such as aromatic dicarboxylic acids such as terephthalic acid and isophthalic acid, and these And the like. Specific examples thereof include nylon 4, nylon 6, nylon 7, nylon 8, nylon 9, nylon 11, nylon 12, nylon 66, nylon 69, nylon 610, nylon 611, nylon. 612, nylon 6T, nylon 6I, nylon MXD
6, nylon 6 / MXD6, nylon MXD6 / MXD
I, nylon 6/66, nylon 6/610, nylon 6/12, nylon 6 / 6T, nylon 6I / 6T and the like. Further, these resins may be crystalline or amorphous.

Examples of the polyacetal resin blended in the polyester composition of the present invention include polyacetal homopolymers and copolymers. Polyacetator
As the homopolymer, the density measured by the method of ASTM-D792 is 1.40 to 1.42 g / cm ³ , A
According to the measuring method of STMD-1238, 190 ℃, load 2
Melt flow ratio (MFR) measured at 160 g is 0.5
Polyacetal in the range of up to 50 g / 10 min is preferred.

Further, as the polyacetal copolymer,
The density measured by the method of ASTM-D792 is 1.
38 to 1.43 g / cm ³ , a polyacetal copolymer having a melt flow ratio (MFR) measured at 190 ° C. and a load of 2160 g by the measuring method of ASTM D-1238 of 0.4 to 50 g / 10 min was obtained. preferable. Examples of these copolymerization components include ethylene oxide and cyclic ethers.

Further, the polyester chip constituting the polyester composition of the present invention has the area strength ratio As (T / G) on the surface of the chip, and the area strength ratio As (T / G) on the surface of the chip and the center part of the chip. Area intensity ratio Ac (T / G) and ratio As (T / G) / Ac (T /
G) is preferably 4.50-8.80 and 0.62-
0.99, more preferably 5.00 to 8.50 and 0.
63-0.98, more preferably 5.50-8.30.
And a chip satisfying 0.65 to 0.97. When the area intensity ratio As (T / G) on the surface is less than 4.00 and the ratio As (T / G) / Ac (T / G) is less than 0.60, the molded body is melt-molded. In that case, the crystal may be easily melted, a crystal nucleus having a crystallization promoting action may not be generated, and the crystallization rate may be very slow. Therefore, when the plugged portion of the hollow molded article is crystallized, crystallization becomes insufficient, and the shrinkage amount of the plugged portion does not fall within the specified value range, which may result in poor capping. Further, in the solid-state polymerized polyester, the above area strength ratio As (T / G) and the above ratio As (T / G) / Ac
In order to make (T / G) below the above lower limit value, it is necessary to use equipment and conditions that make the production cost very high, which is not realistic. On the other hand, when the area intensity ratio As (T / G) on the surface exceeds 9.00 and the ratio As (T / G) / Ac (T / G) exceeds 0.99, the chip surface layer is Dense crystals are generated, the crystallinity is too high, the crystals do not completely melt during melt molding,
May remain as crystal nuclei. As a result, the crystallization speed during heating becomes fast, and the crystallization of the plug part of the hollow molding container becomes excessive. Otherwise, the contents may leak. In addition, the preform for hollow molding is whitened, which makes normal stretching impossible,
Since the thickness variation occurs and the crystallization rate is high, the obtained hollow molded article may have poor transparency, and the variation in transparency may be large.

The term "chip surface" in the present invention means that the thickness from the outer surface of the chip is 0.
The 05 mm sample is a layer obtained by cutting out the sample, and the "chip center portion" is a layer obtained by cutting the sample having a thickness of 0.05 mm from the chip center portion using a microtome.

The above-mentioned polyester composition of the present invention is not necessarily limited to this, but can be produced, for example, as follows. That is, after the melt polycondensation, the molten polyester is extruded into water from a die and cut in water, or the method of extruding into the atmosphere and immediately cutting with cooling water is performed to reduce the chip temperature to about 6
Chips are formed while cooling to a temperature not exceeding 0 to 65 ° C, and then the polyester chips formed into chips are drained and then subjected to a vibrating sieving process, or a process other than a predetermined size by a vibrating sieving process and an airflow classification process using an air flow. Chips, fines, and film-like substances are removed and sent to a temporary storage tank by the plug transport system or bucket conveyor system. Chips are taken out from the tank by a screw type feeder, and transported to the next step by a plug transportation method or a bucket type conveyor transportation method, and an air flow classification step by an air flow is provided immediately before the next step. Fines are removed. Then, the melt-polycondensed prepolymer is crystallized in a continuous crystallization apparatus, and then 195 to 21 under a flow of an inert gas using a continuous moving bed type solid-state polymerization apparatus.
Solid phase polymerization is performed at 5 ° C. for 5 to 25 hours. When transporting the prepolymer chips to a pre-crystallization facility or transporting the polyester chips after solid state polymerization to a sieving process or a storage tank, all of these transports are a plug transport system or a bucket type conveyor transport system. The use of a screw feeder to remove chips from the crystallizer or solid-state polymerization reactor should minimize impact between chips and process equipment, transportation piping, etc. Use manufacturing equipment that can Thus, the area intensity ratio As (T / G) on the surface of the chip is within the range of 4.00 to 9.00, and the ratio As (T / G) / Ac (T / G) is less than 0. 6
It can be in the range of 0 to 0.99.

Then, in the production of the polyester composition in which the above-mentioned polyolefin resin or the like is blended in the present invention, the resin such as the above-mentioned polyolefin resin is directly added to the polyester having the above-mentioned characteristics so that the content thereof falls within the above range. Melt kneading, or by a conventional method such as a method of adding as a master-batch and melt kneading, the resin, the polyester production step, for example, during melt polycondensation, immediately after melt polycondensation, pre-crystallization Immediately after solidification, during solid-phase polymerization, immediately after solid-phase polymerization, or during the steps from the end of the manufacturing step to the molding step, etc., or directly added as powder or granules, or A method of mixing the polyester chip by a method of contacting with the resin member under flowing conditions, or a method of melt-kneading after the contact treatment. Rukoto can also.

Here, as a method for bringing the polyester chip into contact with the resin member under flowing conditions, it is preferable to bring the polyester chip into collision contact with the member in the space where the resin member exists. Specifically, for example, immediately after melt polycondensation of polyester, immediately after pre-crystallization, immediately after solid-phase polymerization, etc., and during filling / discharging of a transportation container at a transportation stage as a product of polyester chips, In addition, at the time of loading the molding machine at the molding stage of the polyester chip, pneumatic transportation pipe, gravity transportation pipe,
Part of the silo, the magnet part of the magnet catcher, etc. is made of the resin, or the resin is lined, or the resin member such as a rod-shaped or net-shaped body is installed in the transfer path. Then, a method of transferring the polyester chips can be mentioned. The contact time of the polyester chip with the member is usually an extremely short time of about 0.01 seconds to several minutes, but a small amount of the resin can be mixed into the polyester.

In the polyester production process, in the step of forming a melt-polymerized polymer into chips, the solid-phase polymerization step, the step of transporting the melt-polymerized polymer chips and the solid-state polymerized polymer chips, etc., the size originally set at the time of granulation Granules, powder, etc., which are considerably smaller than those of chips, are generated. Here, such fine particles and powder are referred to as fine, and a thin film-like material is referred to as a film-like material. In the process of producing polyester, in addition to using high-purity raw materials and auxiliary materials, filtration of molten polycondensation polymer, filtration of cooling water for polyester chips, filtration of water introduced from outside the system for water treatment of chips, Take measures to prevent foreign substances and contaminants other than polyester from being mixed by filtering the gas used for transportation, etc., so that the fine and film-like substances should not contain foreign substances and contaminants other than polyester. You can

Such fine or film-like material has a property of promoting crystallization, and when it is present in a large amount, a molded article molded from such a polyester composition, particularly a bottle, is very transparent. In some cases, the shrinkage amount at the time of crystallization of the bottle mouth plug part does not fall within the specified range and the cap cannot be sealed.

The fine content of the polyester having the same composition as the polyester in the polyester composition of the present invention is 0.1 to 5000 ppm, preferably 0.1 to 3 ppm.
000 ppm or less, more preferably 0.1 to 1000 p
pm or less, more preferably 0.1 to 500 ppm or less, and most preferably 0.1 to 100 ppm or less. If the blending amount is less than 0.1 ppm, the crystallization rate will be very slow, and the crystallization of the plug portion of the hollow molding container will be insufficient, so that the shrinkage amount of the plug portion falls within the specified range. It does not fit, capping becomes impossible, and the stretch-heat-fixing mold for molding the heat-resistant hollow molded container is heavily soiled, and it is necessary to clean the mold frequently when trying to obtain a transparent hollow molded container. It is in. When it exceeds 5000 ppm, the crystallization rate becomes fast, and the crystallization of the plug part of the hollow molding container becomes excessive, so that the shrinkage amount of the plug part does not fall within the specified range, and There is a tendency for capping failure, leakage of contents, and whitening of the hollow-molding preform, which makes normal stretching impossible. In particular, when the capacity of the hollow molded body is larger than 1500 cc, this tendency becomes remarkable, and only a hollow molded body having no commercial value may be obtained.

The fine peak constituting the polyester composition of the present invention has a melting peak temperature on the highest temperature side of the melting peak temperature measured by DSC, which is preferably 265 ° C. or lower, more preferably 263 ° C. or lower. , And more preferably 2
It is necessary to be 60 ° C or lower. When the fine particles having a melting peak temperature exceeding 265 ° C. are included, the crystals are not completely melted under the normally used melt molding conditions and tend to remain as crystal nuclei. For this reason, when the hollow molded article plug portion is heated, the crystallization speed is increased, and thus the crystallization of the plug portion becomes excessive. As a result, the amount of contraction of the spout may not fall within the specified value range, and capping of the spout may result in leakage of the contents. In addition, the preform for hollow molding is whitened, which makes normal stretching impossible,
Since the thickness variation occurs and the crystallization rate is high, the obtained hollow molded article may have poor transparency, and the transparency may vary greatly. In addition, the obtained sheet-like material has poor transparency and a high crystallization rate, so normal stretching is impossible, and only a stretched film with large thickness unevenness and poor transparency may be obtained.

However, when it is desired to obtain a hollow-molding preform or sheet having good transparency and stretchability from a polyester composition containing fines having a melting peak temperature of more than 265 ° C. It must be melt-molded at a high temperature of 300 ° C or higher. However, such 300 ℃
At the above-mentioned high temperatures, the thermal decomposition of polyester becomes severe, and a large amount of by-products such as acetaldehyde and formaldehyde are generated, resulting in a great influence on the flavor of contents such as molded products. is there. Further, when the polyester composition of the present invention contains at least one resin selected from the group consisting of the following polyolefin resins, polyamide resins, and polyacetal resins, these resins generally correspond to the present invention. In many cases, it is inferior to polyester in thermal stability.
In molding at a high temperature of 00 ° C. or higher, thermal decomposition is caused to generate a large amount of by-products, so that the flavor of the obtained molded product or the like has a greater effect.

The content of the film-like material having the same composition as the polyester in the polyester composition of the present invention is preferably 10 ppm or less, preferably 5 ppm or less, more preferably 1 ppm or less. The film-like substance has a higher crystallization-promoting effect than fine film, probably because it is oriented and crystallized, and therefore the lower limit of the compounding amount that does not have a bad influence is lowered. If the blending amount exceeds 10 ppm, the crystallization rate will be extremely high, and the crystallization of the plug portion of the hollow molding container will be excessive, so that the shrinkage amount of the plug portion will not fall within the specified range, In some cases, capping of the spout becomes defective, contents leak, and the preform for hollow molding is whitened, which makes normal stretching impossible. The lower limit of the content of the film-like material is preferably 0.1 ppm for economical reasons.

The melting peak temperature of the film in the polyester composition of the present invention on the highest side of the melting peak temperature measured by DSC is the same as or higher than that of fine, 260 ° C to about 290 ° C. Two
In the film-like material having a melting peak temperature of more than 65 ° C., the crystals do not completely melt under the normally used melt molding conditions and remain as crystal nuclei. When the shape is large, it is not completely melt-dispersed and is present in a streak shape in the obtained molded product, and the part is whitened or the transparency is deteriorated because crystallization is extremely promoted. Or

In the present invention, when the sodium content, magnesium content, silicon content and calcium content in the cooling water in the chipping step are N, M, S and C, respectively, the following (3) It is preferable that the melt polycondensed polyester is chipped so as to satisfy at least one, and preferably all of (4) to (6). N ≤ 1.0 (ppm) (3) M ≤ 0.5 (ppm) (4) S ≤ 2.0 (ppm) (5) C ≤ 1.0 (ppm) (6)

The sodium content (N) in the cooling water is preferably N ≦ 0.5 ppm, more preferably N
≦ 0.1 ppm. The magnesium content (M) in the cooling water is preferably M ≦ 0.3 ppm, more preferably M ≦ 0.1 ppm. The content (S) of silicon in the cooling water is preferably S ≦ 0.5 ppm, more preferably S ≦ 0.3 ppm. Further, the calcium content (C) in the cooling water is preferably C ≦ 0.5 ppm, more preferably C ≦ 0.1.
It is ppm.

The lower limit values of sodium content (N), magnesium content (M), silicon content (S) and calcium content (C) in the cooling water are N ≧
0.001ppm, M ≧ 0.001ppm, S ≧ 0.0
2 ppm and C ≧ 0.001 ppm. In order to make it below such a lower limit value, enormous capital investment is required, and the operating cost becomes very high, so that economical production tends to be difficult.

When cooling water that does not satisfy the above conditions is used, these metal-containing compounds adhere to the surface of the polyester chip, and the final solid-phase-polymerized polyester obtained has a very high crystallization rate. It is not preferable because the fluctuation becomes large. The content of the metal in industrial water fluctuates considerably throughout the year, and the content of the metal adhering to the polyester fluctuates according to this fluctuation.
As compared with the case where cooling water satisfying at least one of (6) to (6) is used, the transparency of the molded product from the polyester obtained by using industrial water as cooling water at the time of chipping is poor, and The fluctuation is very large. In addition, from the above (3)
It is preferable that (6) satisfies all the requirements.

Further, when the solidified polycondensation of the melted polycondensed polyester which was made into chips while being cooled by using cooling water which deviates from the above conditions, it was attached to the chip surface in the chipping step and brought into the solid phase polymerization reactor. The metal-containing material adheres to the vessel wall of the solid-state polymerization device together with a part of the surface layer of the polyester chip, and when this is heated at a high temperature of about 170 ° C. or more for a long time, a scale having a high metal content is obtained. It adheres to the vessel wall. Then, this sometimes peels off and mixes into the polyester chip, and becomes a foreign substance in the molded body such as a bottle, which may cause a problem of reducing the commercial value.

Further, when the sheet is produced, the above-mentioned scale is clogged with the molten polymer filtration filter at the time of film formation, the filtration pressure of the filter increases sharply, and the operability and the productivity are deteriorated. There may be a problem that

A method for suppressing the sodium content, magnesium content, silicon content, and calcium content of the cooling water of the chips to the above ranges will be illustrated below, but the present invention is not limited thereto.

In order to reduce sodium, magnesium, calcium, and silicon in the cooling water, a device for removing sodium, magnesium, calcium, and silicon is installed at at least one place in the process until industrial water is sent to the chip forming process. To do. A filter is installed to remove clay minerals such as particulate silicon dioxide and aluminosilicate. Examples of the device for removing sodium, magnesium, calcium, and silicon include an ion exchange device, an ultrafiltration device, and a reverse osmosis membrane device. Further, the particle size existing in the introduced water introduced from outside the system is 1 to 25 μm.
It is desirable to use water having m particles of 50,000 particles / 10 ml or less. The number of particles having a particle size of 1 to 25 μm in the introduced water is preferably 10,000 particles / 10 ml or less,
It is more preferably 1000 pieces / 10 ml or less, and particularly preferably 100 pieces / 10 ml or less.

The lower limit value of particles having a particle size of 1 to 25 μm is 1 particle / 10 ml or more, and enormous equipment investment is required to make the particle size lower than the lower limit value, and the operating cost becomes very high. Economical production can be difficult.

Particles having a particle size of more than 25 μm in the introduced water are
Although not particularly specified, preferably 2000 /
It is 10 ml or less, more preferably 500 pieces / 10 ml or less, further preferably 100 pieces / 10 ml, and particularly preferably 10 pieces / 10 ml or less.

The particles having a particle size of less than 1 μm in the introduced water are not particularly specified in the present invention, but in order to obtain a polyester which gives a transparent molded product or a molded product having an appropriate crystallization rate, The smaller the number, the better. Particle size 1
The number of particles less than μm is preferably 100,000 /
10 ml or less, more preferably 50,000 pieces / 10 ml
Or less, more preferably 20,000 pieces / 10 ml or less,
Particularly preferably, it is 10,000 pieces / 10 ml or less. 1
As a method for removing and controlling particles having a size of μm or less from water, a microfiltration method or an ultrafiltration method using a membrane such as a ceramic membrane or an organic membrane can be used.

50,000 particles / 10 ml of particles having a particle size of 1 to 25 μm in the introduced water to be introduced in the chip forming step below.
The control method is illustrated below, but the present invention is not limited to this.

As a method for reducing the number of particles in water to 50,000 particles / 10 ml or less, an apparatus for removing particles is installed at at least one place until natural water such as industrial water is supplied to the chip forming step. Preferably, from a natural water sampling port, a device for removing particles is installed during the chip formation step, and the water is supplied to the chip formation step.
The content of particles having a particle size of 1 to 25 μm is 50,000 / 10
It is preferably less than or equal to ml. Examples of the device for removing particles include a filter filtration device, a membrane filtration device, a sedimentation tank, a centrifuge, and a foam entrainment treatment device. For example, in the case of a filter filtration device, examples thereof include a belt filter system, a bag filter system, a cartridge filter system, a centrifugal filtration system and the like. Among them, the belt filter method, centrifugal filtration method,
A bag filter type filtration device is suitable. If it is a belt filter type filtering device,
Examples include paper, metal and cloth. Further, in order to efficiently remove particles and efficiently introduce water, the size of the mesh of the filter is 5 to 100 μm, preferably 10 or more, preferably 7 or more.
It is preferably 0 μm or less, more preferably 15, and even more preferably 40 μm or less.

In addition, the polyester composition of the present invention
The amount of increase of the cyclic trimer when melted at a temperature of 0 ° C. for 60 minutes is preferably 0.50% by weight or less. The amount of increase of the cyclic trimer is preferably 0.3% by weight or less, more preferably 0.1% by weight or less. 290 ° C
When the amount of increase of the cyclic trimer when melted at the temperature of 60 minutes exceeds 0.50% by weight, the cyclic trimer is melted when the resin for molding is melted.
In some cases, the amount of monomers increases, the amount of oligomers attached to the surface of the heating mold rapidly increases, and the transparency of the obtained hollow molded article is extremely deteriorated.

The polyester composition of the present invention, in which the amount of increase in the cyclic trimer when melted at a temperature of 290 ° C. for 60 minutes is 0.50% by weight or less, was obtained after melt polycondensation or after solid phase polymerization. It can be produced by deactivating the polyester polycondensation catalyst. Examples of the method for deactivating the polyester polycondensation catalyst include a method in which the polyester chips are subjected to contact treatment with water, steam, or a steam-containing gas after melt polycondensation or after solid-phase polymerization.

A method of contacting the polyester chips with water, steam or a gas containing steam to achieve the above object will be described below. Examples of the hot water treatment method include a method of immersing in hot water and a method of spraying water on the chips with a shower. The treatment time is 5 minutes to 2 days, preferably 10 minutes to 1 day, more preferably 30 minutes to 10 hours, and the water temperature is 20 to 180 ° C., preferably 40.
To 150 ° C, more preferably 50 to 120 ° C.

The method for industrially carrying out water treatment is exemplified below, but the method is not limited to this. The treatment method may be either a continuous method or a batch method, but the continuous method is preferable for industrial use.

When the polyester chips are subjected to water treatment in a batch system, a silo type treatment tank may be used. That is, the polyester chips are received in silos in a batch system and treated with water. When the polyester chips are treated with water continuously, the polyester chips can be continuously or intermittently received from the upper portion of the tower-type treatment tank for water treatment. This conceptual diagram is shown in FIG.

Regardless of whether the water treatment method is continuous or batchwise, if all or most of the treated water discharged from the treatment tank is treated as industrial wastewater, a large amount of new water can be used. Not only that, but there is concern that the increase in the amount of wastewater will have an impact on the environment. That is, by returning at least a part of the treated water discharged from the treatment tank to the water treatment tank and reusing it, it is possible to reduce the necessary amount of water, and it is possible to reduce the effect on the environment due to the increase in the amount of drainage. If the wastewater returned to the water treatment tank maintains a certain temperature,
Since the heating amount of the treated water can be reduced, it is preferable that the treated water discharged from the treated layer be returned to the water treated layer and reused. In addition, by reusing water, the flow rate of treated water in the treated layer can be increased, and as a result, fines attached to the polyester chips can be washed away,
Fine removal effect is also created. Here, as the treated water that has been discharged from the water treatment tank and then returned to the treatment tank and reused, the water discharged from the overflow port of the water treatment tank and the polyester chips from the treatment tank are used together. There is treated water that has been drained and then separated from the chips.

However, in the treated water discharged from the treatment tank in the water treatment, fines already attached to the polyester chips at the stage of receiving the polyester chips in the treatment tank, polyester chips during the water treatment, or the treatment tank wall. Contains polyester fines generated by friction. In addition, the new treated water contains fine particles derived from inorganic substances, spoiled plants, and organic fine particles derived from animals.

Therefore, when the treated water discharged from the treatment tank is returned to the treatment tank for reuse, the amount of fines and fine particles contained in the treated water in the treatment tank gradually increases and is contained in the treated water. In some cases, fines and fine particles adhered to the walls of the processing tank and the walls of the piping to clog the piping.

Further, fines and fine particles contained in the treated water adhere to the polyester chip, and thereafter, fines and fine particles adhere to or permeate the polyester chip at the stage of drying and removing water. The content becomes very large, the polyester obtained in this way is promoted in crystallinity, the transparency of the obtained bottle is deteriorated, and the crystallinity at the time of crystallization of the bottle cap is too large. As a result, the dimensions of the spigot part do not meet the standard, which may result in defective capping of the spigot part and leakage of the contents.

Therefore, in the present invention, after being discharged from the water treatment tank, at least a part of it is returned to the treatment tank and reused, so that the particle size existing in the treated water is 1 to 40 μm.
100,000 particles / 10 ml or less, preferably 80,000 particles / 10 ml or less, more preferably 500
It is desirable to keep the number of cells per 100 pieces / 10 ml or less. Here, the treated water thus returned to the treatment tank and reused is referred to as recycled water.

Below, the particle size of the recycled water is from 1 to 40.
A method of reducing the number of μm particles to 100,000 particles / 10 ml or less is illustrated, but the present invention is not limited to this. The number of particles having a particle size of 1 to 40 μm in the recycled water is 100,000.
As a method for reducing the number of particles per 10 ml or less, an apparatus for removing fines and fine particles is installed at at least one place in the process until the treated water discharged from the treating tank is returned to the treating tank again. Examples of the device for removing fines and fine particles include a filter-filtration device, a membrane filtration device, a settling tank, a centrifuge, and a foam entrainment treatment device. For example, in the case of a filter-filter device, examples of the filter device include an automatic self-cleaning system, a belt filter system, a bag filter system, a cartridge filter system, and a centrifugal filtration system. Among them, a belt filter type, a centrifugal filtration type, and a bag filter type filtration device are suitable for continuous operation. Further, in the case of a belt filter type filtering device, examples of the filter material include paper, metal, cloth and the like. Further, in order to remove fines and to flow the treated water efficiently, the size of the mesh of the filter is 5 to 100 μm, preferably 5 to 70 μm.
More preferably, it is 5 to 40 μm.

Further, the water introduced from outside the system can be discharged from the water treatment tank together with the chips and then supplied to the treatment tank together with the treated water to be reused after being subjected to treatment such as filtration. is there.

When the polyester chips are contacted with water vapor or a gas containing water vapor, the treatment is carried out at 50 to 50%.
Steam or steam-containing gas or steam-containing air at a temperature of 150 ° C., preferably 50 to 110 ° C. is preferably supplied or present as steam in an amount of 0.5 g or more per 1 kg of granular polyethylene terephthalate. The granular polyethylene terephthalate is contacted with steam.

The contact between the polyester chips and water vapor is usually 10 minutes to 2 days, preferably 20 minutes.
It will be held for 10 hours.

The method of industrially carrying out the contact treatment between the granular polyethylene terephthalate and steam or a gas containing steam will be illustrated below, but the method is not limited to this. Further, the treatment method may be either a continuous method or a batch method.

When the polyester chips are subjected to the contact treatment with steam in a batch system, a silo type treatment apparatus can be used. That is, the polyester chips are received in a silo, and steam or a steam-containing gas is supplied in a batch method to perform contact treatment.

When the polyester chips are continuously contacted with steam, granular tower terephthalate is continuously received from the upper part in a tower-type processing apparatus, and steam is continuously supplied in cocurrent or countercurrent to contact steam. Can be processed.

As described above, when treated with water or steam, the granular polyethylene terephthalate is drained by a draining device such as a vibrating screener or a simon carter if necessary, and the conveyor is used for the next drying step. Transfer.

For drying the polyester chips that have been contact-treated with water or steam, a commonly used polyester drying process can be used. As a method for continuously drying, a hopper-type aeration dryer in which polyester chips are supplied from the upper part and a drying gas is aerated from the lower part is usually used.

As a dryer for drying in a batch system, drying may be carried out under atmospheric pressure while ventilating a drying gas. Although atmospheric air may be used as the dry gas, dry nitrogen and dehumidified air are preferable from the viewpoint of preventing a decrease in molecular weight due to hydrolysis or thermal oxidative decomposition of the polyester.

As another means for deactivating the polycondensation catalyst, there may be mentioned a method of deactivating the polymerization catalyst by adding and mixing a phosphorus compound to the melt of the polyester after solid phase polymerization.

The solid compound polyester may be blended with the phosphorus compound by dry blending the solid compound polyester with the phosphorus compound, or by melt kneading and blending the phosphorus compound with the polyester master-batch chip and the solid polymer polyester chip. A method in which a predetermined amount of a phosphorus compound is blended with polyester by a method of mixing and then melted in an extruder or a molding machine to inactivate the polycondensation catalyst, and the like.

The phosphorus compound used is phosphoric acid,
Examples include phosphorous acid, phosphonic acid and their derivatives. Specific examples include phosphoric acid, phosphoric acid trimethyl ester, phosphoric acid triethyl ester, phosphoric acid tributyl ester, phosphoric acid triphenyl ester, phosphoric acid monomethyl ester, phosphoric acid dimethyl ester, phosphoric acid monobutyl ester, phosphoric acid dibutyl ester, Phosphoric acid, trimethyl phosphite, triethyl phosphite, tributyl phosphite, methylphosphonic acid,
Methylphosphonic acid dimethyl ester, ethylphosphonic acid dimethyl ester, phenylphosphonic acid dimethyl ester, phenylphosphonic acid diethyl ester, phenylphosphonic acid diphenyl ester, and the like, which may be used alone or in combination of two or more. You may use together.

As a gas for contacting the polyester after the melt polycondensation step or the solid phase polymerization step, or the polyester after the contact treatment with the member made of the resin, 1,000,000 particles having a particle size of 0.3 to 5 μm (pieces / piece) It is desirable to use a gas introduced from outside the system, which is less than or equal to cubic feet, preferably less than or equal to 500,000 (pieces / cubic feet), and more preferably less than or equal to 100,000 (pieces / cubic feet). Particles exceeding 5 μm in gas are
Although not particularly limited, it is preferably 5 (pieces / cubic foot) or less, more preferably 1 (pieces / cubic foot).
G) The following.

In the polyester manufacturing process, a container such as a silo, a molding machine hopper, a transportation container, etc. is passed through each step such as a melt polycondensation step, a solid-state polymerization step, etc., such as a sieving step and an air stream classification step. In order to transport and dry the polyester during these steps, air around the treatment equipment is generally taken into the steps by a blower or the like and used. Conventionally, such air is either left untreated or used according to JIS B 9908 (199).
It was generally used only after being treated by a cleaner equipped with a low-performance filter unit such as type 3 defined in 1). However, the polyester treated in such a process may cause a problem that only a molded product having poor transparency can be obtained. In particular, before and after the contact treatment step with the member made of the resin, when the air having the quality as described above is used as the gas that comes into contact with the polyester, the crystallization rate and the transparency of the obtained molded product largely vary. There is a high possibility that it will become a problem.

Therefore, in the method for producing polyester by the contact treatment with the member made of the resin of the present invention, after the melt polycondensation, the solid phase polymerization, the water treatment or the contact treatment with the member made of the resin, Among the polyesters, at least one polyester has a particle size of 0.3 to 5 as a gas to be contacted in any one of a transporting step to the next step, a sieving step, a storing step and a container filling step.
It is desirable to use a gas having a particle diameter of μm of 1,000,000 (particles / cubic foot) or less, which is introduced from outside the system.

Particles having a particle size of less than 0.3 μm in a gas are not particularly specified, but the smaller the number is preferable in order to obtain a resin giving a transparent molded body.
The number of particles having a particle size of less than 0.3 μm is preferably 100.
It is 00000 (pieces / cubic feet) or less, more preferably 5,000,000 (pieces / cubic feet) or less, and further preferably 2000000 (pieces / cubic feet or less).

A method for controlling the number of particles having a particle size of 0.3 to 5 μm in the gas introduced from outside the system to 1,000,000 (particles / cubic foot) or less is illustrated below, but the present invention is not limited to this. Not something to do. As a method for reducing the number of particles having a particle diameter of 0.3 to 5 μm in the gas introduced from outside the system to 1,000,000 (particles / cubic foot) or less, a step of contacting the gas introduced from the outside with the polyester chips A cleaning device for removing the particles is installed at least at one or more places inside. When the gas is air near the processing equipment,
During the process until the air introduced by the blower from the air inlet comes into contact with the polyester chip, JIS
Form 1 or / specified in B 9908 (1991)
Further, it is preferable to install a gas purifying apparatus equipped with a type 2 filter unit and set the number of particles having a particle size of 0.3 to 5 μm in the air to 1,000,000 (pieces / cubic foot) or less. In addition, JIS B 99 is installed in the air intake port.
It is possible to extend the life of the filter unit by installing the gas cleaning device equipped with the filter unit of the type 3 defined in 08 (1991) and using it together with the gas cleaning device equipped with the filter unit. Is.

JIS B 99 for removing particles in a gas
As a material of the ultra-high performance filter (hereinafter referred to as HEPA filter) unit of type 1 defined in 08 (1991), a filter paper made of glass fiber can be mentioned.

In addition, JIS B 9908 (1991)
Examples of the material for the high-performance filter unit of the type 2 defined in 1. include a filter made of polypropylene fiber, a filter made of a laminate of Teflon (R) film and PET fiber cloth, and the like. Generally, an electrostatic filter made of polypropylene fiber is used.

In addition, JIS B 9908 (1991)
Examples of the material of the low-performance filter unit of the type 3 defined in 1. include non-woven fabric made of PET or polypropylene.

The intrinsic viscosity of the polyester according to the present invention is
It is preferably 0.55 to 1.50 deciliter / gram, more preferably 0.58 to 1.30 deciliter / gram. The intrinsic viscosity of polyester is 0.5
When it is less than 5 deciliters / gram, the transparency of a molded article obtained by melt molding the polyester composition of the present invention,
The heat resistance and mechanical properties may not be sufficiently satisfied. Further, when the intrinsic viscosity exceeds 1.50 deciliter / gram, the resin temperature becomes high during melting by a molding machine or the like and thermal decomposition becomes severe, and free low molecular weight compounds that affect aroma retention increase. However, problems such as yellowing of the molded product may occur.

The acetaldehyde content of the polyester according to the present invention is 50 ppm or less, preferably 30 ppm.
ppm or less, more preferably 10 ppm or less, further preferably 5 ppm or less, the formaldehyde content is 2
It is desirable that the content is 0 ppm or less, preferably 10 ppm or less, more preferably 8 ppm or less, and further preferably 4 ppm or less. Acetaldehyde content is 50pp
m or more and / or formaldehyde content of 20p
When it is pm or more, the flavor and odor of the contents such as a container molded from this polyester may be deteriorated.

The amount of diethylene glycol copolymerized in the polyester according to the present invention is preferably 0.5 to 5.0 mol%, more preferably 1.0 to 5.0 mol% of the glycol component constituting the polyester. It is 4.5 mol%, and more preferably 1.5 to 4.0 mol%. When the amount of diethylene glycol is more than 5.0 mol%, the thermal stability may be poor, the molecular weight may be greatly reduced during molding, and the acetaldehyde content and the formaldehyde content may be increased significantly, which is preferable. Absent. When the content of diethylene glycol is less than 0.5 mol%, the transparency of the obtained molded product may deteriorate.

The content of the cyclic trimer of the polyester according to the present invention is 0.70% by weight or less, preferably 0.50.
It is desirable that the content is less than or equal to wt%, more preferably less than or equal to 0.40 wt%, and even more preferably less than or equal to 0.35 wt%. When a heat-resistant hollow molded article or the like is molded from the polyester composition of the present invention, heat treatment is carried out in a heating mold. The number of oligomers attached to the surface of the mold suddenly increases,
The transparency of the obtained hollow molded article may be extremely deteriorated.

In the present invention, the shape of the polyester chip may be any of cylinder type, square type, spherical type or flat plate type. The average particle size is usually 1.5-5 mm,
Preferably 1.6 to 4.5 mm, more preferably 1.
It is in the range of 8 to 4.0 mm. For example, in the case of a cylinder type, it is practical that the length is 1.5 to 4 mm and the diameter is about 1.5 to 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. Further, it is practical that the weight of the chip is in the range of 10 to 30 mg / piece.

The polyester composition of the present invention has a crystallization temperature (hereinafter referred to as "Tc1") when the test piece is heated from a molded product having a thickness of 2 mm obtained by melt-molding the polyester composition.
Range of 150 to 170 ° C, preferably 152 to 165 ° C
It is desirable to be in the range of, and more preferably in the range of 155 to 160 ° C. If Tc1 exceeds 170 ° C,
The heating crystallization rate becomes very slow, and the improvement effect of crystallization cannot be expected. Further, when Tc1 is lower than 150 ° C., the transparency of the hollow molded article may be deteriorated, which may cause a problem.

The polyester composition of the present invention is a PET obtained by using a raw material such as dimethyl terephthalate or terephthalic acid recovered by purifying a used PET bottle by a chemical recycling method as at least a part of the starting raw material.
And PET flakes and chip PET that are used PET bottles purified and collected by the mechanical recycling method
It can be used as a mixture with.

It is also possible to simultaneously use a saturated fatty acid monoamide, an unsaturated fatty acid monoamide, a saturated fatty acid bisamide, an unsaturated fatty acid bisamide and the like in the polyester composition of the present invention.

Examples of the saturated fatty acid monoamide include lauric acid amide, palmitic acid amide, stearic acid amide and behenic acid amide. Examples of unsaturated fatty acid monoamides include oleic acid amide, erucic acid amide ricino-acid amide, and the like. Examples of the saturated fatty acid bisamide include methylenebisstearic acid amide, ethylenebiscapric acid amide, ethylenebislauric acid amide, ethylenebisstearic acid amide, ethylenebisbehenic acid amide, hexamethylenebisstearic acid amide, and hexamethylenebisbehenic acid. Examples include amides. Examples of unsaturated fatty acid bisamides include ethylenebisoleic acid amide and hexamethylenebisoleic acid amide. Preferable amide compounds are saturated fatty acid bisamide, unsaturated fatty acid bisamide and the like. The compounding amount of such an amide compound is 1
It is in the range of 0 ppb to 1 × 10 ⁵ ppm.

The polyester composition of the present invention may also contain a metal salt compound of an aliphatic monocarboxylic acid having 8 to 33 carbon atoms such as naphthenic acid, caprylic acid, capric acid, lauric acid,
Lithium salts, sodium salts, potassium salts, magnesium salts, calcium salts, and cobalt of saturated and unsaturated fatty acids such as myristic acid, palmitic acid, stearic acid, behenic acid, montanic acid, melissic acid, oleic acid, and linoleic acid. It is also possible to use salt and the like together. The compounding amount of these compounds is in the range of 10 ppb to 300 ppm.

The polyester composition of the present invention can be preferably used as a hollow molding, a tray, a packaging material such as a biaxially stretched film, a film for coating a metal can, and the like. Further, the polyester composition of the present invention can be used as a constituent layer of a multilayer molded body, a multilayer film or the like.

The polyester of the present invention can be formed into films, sheets, containers, and other packaging materials by using a commonly used melt molding method. Further, it is possible to improve mechanical strength by stretching PET in at least a uniaxial direction. The stretched film made of PET of the present invention is a sheet-shaped product obtained by injection molding or extrusion molding, and any stretching method of uniaxial stretching, sequential biaxial stretching, and simultaneous biaxial stretching that is usually used for stretching PET. Is molded using. It is also possible to form into a recup shape or a tray shape by pressure forming or vacuum forming.

In producing a stretched film, the stretching temperature is usually 80 to 130 ° C. The stretching may be uniaxial or biaxial, but biaxial stretching is preferable from the viewpoint of practical physical properties of the film. In the case of uniaxial stretching, the stretching ratio is usually 1.1 to 10 times, preferably 1.5 to 8 times, and in the case of biaxial stretching, it is usually 1.1 to 8 times in each of the machine direction and the transverse direction. , Preferably 1.5 to 5 times. Also, the vertical / horizontal ratio is usually 0.5.
˜2, preferably 0.7 to 1.3. The obtained stretched film can be further heat-fixed to improve heat resistance and mechanical strength. Heat fixation is usually under tension, 120 ° C
~ 240, preferably 150 ~ 230 ℃, usually several seconds ~
It is performed for several hours, preferably several tens of seconds to several minutes.

In producing the hollow molded article, a briform molded from the PET of the present invention is stretch blow-molded, and an apparatus conventionally used for blow-molding PET can be used. Specifically, for example, a preform is once molded by injection molding or extrusion molding, and as it is or after processing the plug portion and the bottom portion, it is reheated, and biaxial stretch blow molding such as hot parison method or cold parison method. The law applies. The molding temperature in this case, specifically the temperature of each part of the cylinder and nozzle of the molding machine, is usually in the range of 260 to 290 ° C. The stretching temperature is usually 70 to 120 ° C, preferably 90 to 110 ° C,
The stretching ratio is usually 1.5 to 3.5 times in the longitudinal direction and 2 to 5 times in the circumferential direction. The obtained hollow molded article,
Although it can be used as it is, it is generally used for beverages requiring heat filling, such as fruit juice and oolong tea.
Further, it is heat-set in a blow mold to give it heat resistance before use. The heat setting is usually 100 to 200 ° C., preferably 120 to 180 ° C. under tension such as compressed air.
At a temperature of several seconds to several hours, preferably several seconds to several minutes.

Further, in order to impart heat resistance to the spout,
The plug part of the preform obtained by injection molding or extrusion molding is crystallized in an oven equipped with a far infrared or near infrared heater, or the plug part is molded with the above heater after bottle molding. Crystallize.

The polyester composition used in the present invention may contain other additives, if necessary, such as known ultraviolet absorbers, antioxidants, oxygen absorbers, oxygen scavengers, lubricants and reactions added from the outside. Lubricant, mold release agent,
You may mix | blend various additives, such as a nucleating agent, a stabilizer, an antistatic agent, and a dye and a pigment.

When the polyester composition of the present invention is used for a film, in order to improve handling properties such as slipperiness, winding property and blocking resistance, calcium carbonate and magnesium carbonate are added to the polyester composition. Inorganic particles such as barium carbonate, calcium sulfate, barium sulfate, lithium phosphate, calcium phosphate and magnesium phosphate, organic salt particles such as terephthalate salts such as calcium and calcium oxalate, barium, zinc, manganese and magnesium and divinylbenzene, Inert particles such as cross-linked polymer particles such as styrene, acrylic acid, methacrylic acid, vinyl monomers of acrylic acid or methacrylic acid, homopolymers or copolymers thereof can be contained. In addition, the measuring method of the main characteristic value in this invention is demonstrated below.

[0121]

EXAMPLES The present invention will now be specifically described with reference to examples, but the present invention is not limited to these examples.
In addition, the measuring method of the main characteristic value in this invention is demonstrated below.

(1) Intrinsic viscosity of polyester (hereinafter referred to as "I
V)) 1,1,2,2-tetrachloroethane / phenol (2: 3 weight ratio) in a mixed solvent at 30 ° C.

(2) As (T /
G) and Ac (T / G) measurement and As (T / G)
/ Ac (T / G) calculation An infrared spectrum was obtained by microscopic / FT-IR (Fourier conversion infrared spectrometer) for the sample of the surface and the central part having a thickness of 0.050 mm cut out by a microtome. It was measured. From the obtained infrared spectrum, an absorption band derived from the T (trans) structure was found to be 972 cm ^-1 and G (Goss).
1042 cm ^-1 was selected as the absorption band derived from the structure, and the area intensity in the range surrounded by the tangent line (base line) drawn at the high wave number end and the low wave number end of each absorption band was measured. As (T / G) and Ac (T / G) were calculated from the area intensities of the T absorption band and the G absorption band obtained on the surface and the central portion, and As (T / G) / Ac (T
/ G) was calculated. (3) Diethylene glycol content of polyester (hereinafter referred to as "DEG content") Decomposed by methanol, the amount of DEG was quantified by gas chromatography, and expressed as a ratio (mol%) to all glycol components. .

(4) Content of cyclic trimer of polyester (hereinafter referred to as "CT content") A sample is dissolved in a hexafluoroisopropanol / chloroform mixture solution, and chloroform is further added to dilute the mixture. To this is added methanol to precipitate the polymer, which is then filtered. The filtrate was evaporated to dryness, adjusted to a constant volume with dimethylformamide, and the cyclic trimer composed of ethylene terephthalate units was quantified by liquid chromatography.

(5) Acetaldehyde content of polyester (hereinafter referred to as “AA content”) Sample / distilled water = 1 g / 2 cc A nitrogen-substituted glass ampoule was sealed with the upper part and subjected to extraction at 160 ° C. for 2 hours. After treatment and cooling, acetaldehyde in the extract was measured by high sensitivity gas chromatography and the concentration was expressed in ppm.

(6) Increasing amount of cyclic trimer during melting of polyester (ΔCT amount) 3 g of dried polyester chips were put in a glass test tube and immersed in an oil bath at 290 ° C. for 60 minutes under a nitrogen atmosphere to melt. Let The amount of cyclic trimer increase during melting is determined by the following formula. Increase of cyclic trimer at melting (wt%) = cyclic 3 after melting
Content of monomer (% by weight) -Content of cyclic trimer before melting (% by weight)

(7) Measurement of Fine Content and Film Content The resin (0.5 kg) according to JIS-Z8801 was used as a sieve (A) with a nominal size of 5.6 mm and a nominal size of 1.7.
A sieve (diameter 20 cm) (B) having a metal mesh of mm was placed on the sieve in which the two stages were combined, and sieved with a rocking type sieving tow machine SNF-7 manufactured by Terraoka at 1800 rpm for 1 minute. This operation was repeated, and a total of 20 kg of the resin was sieved. If, in addition to the film-like material, two or more chips fused to each other or a chip-like material cut into a size larger than the normal shape are captured on the sieve (A), The remaining film-like material from which the syrup was removed and the fines sieved off under the sieve (B) were separately washed with ion-exchanged water, filtered with a G1 glass filter manufactured by Iwaki Glass Co., Ltd., and collected. These are put together with the glass filter in a dryer at 100 ° C.
After drying for 2 hours, it was cooled and weighed. The same operation of washing with ion-exchanged water and drying was repeated again to confirm that the weight became constant, and the weight of the glass filter was subtracted from this weight to obtain the fine weight and the weight of the film-like material.
Fine content or film content is fine weight or film weight / total screened resin weight. The total content is calculated from these values.

(8) Measurement of fine peak temperature of fine powder Differential scanning calorimeter (DS) manufactured by Seiko Denshi Kogyo KK
C), measured using RDC-220. In (7),
Fines collected from 20 kg of polyester were dried under reduced pressure at 25 ° C for 3 days, and a sample of 4 m was used for each measurement.
DSC measurement at a temperature rising rate of 20 ° C./min using g,
The melting peak temperature on the highest side of the melting peak temperature is determined. The measurement is performed on a maximum of 10 samples, and the average value of the melting peak temperatures on the highest temperature side is obtained. If there is one melting peak temperature, find that temperature.

(9) Average Density of Polyester Chip, Density of Preform Mouth Portion and Density Deviation of Mouth Portion Measured at 30 ° C. with a density gradient tube of calcium nitrate / water mixed solution. Further, the density of the plug portion was obtained as an average value of 10 samples crystallized by the method (10), and the density deviation of the plug portion was obtained from these 10 values.

(10) Density increase due to heating of preform plug part The preform plug part was heat-treated for 60 seconds by a home-made infrared heater, and a sample was sampled from the top surface to measure the density.

(11) Haze (% haze) and molded plate haze unevenness (%) Body (5 mm in thickness) of the following (13) and body of hollow molded body (14) (thickness of about 0.45 mm) ), A sample was cut from the sample, and a haze meter, model NDH manufactured by Nippon Denshoku Co., Ltd.
Measured at 2000. In addition, a forming plate formed 10 times in succession
The haze (wall thickness 5 mm) was measured, and the unevenness of the molded plate haze was determined by the following. Molded plate haze unevenness (%) = maximum haze value (%)-minimum haze value (%)

(12) Crystallization temperature (T
c1) Differential thermal analyzer (DS
C), measured with RDC-220. Using 10 mg of a sample from the center of a 2 mm-thick plate of the following (13) shaped plate. The temperature is raised at a temperature rising rate of 20 ° C./minute, and the peak temperature of the crystallization peak observed during the heating is measured and used as the crystallization temperature during heating (Tc1).

(13) Molding of Stepped Molded Plate A dried polyester was manufactured by Meiki Seisakusho M-150C (D
M) A stepped flat plate mold (surface temperature of about 2 ° C) cooled with water at 10 ° C at a cylinder temperature of 290 ° C by an injection molding machine.
2 ° C.) for molding. The obtained step forming plate is 2,
A plate having a thickness of 3, 4, 5, 6, 7, 8, 9, 10, and 11 mm and a size of about 3 cm × about 5 cm square was provided stepwise, and the weight of one piece was about 146 g. A plate having a thickness of 2 mm is used for measuring Tc1 and a plate having a thickness of 5 mm is used for measuring haze (% haze).

(14) Molding of Hollow Molded Body Polyester was dried with a dryer using dehumidified air, and a preform was molded at a resin temperature of 290 ° C. with an M-150C (DM) injection molding machine manufactured by each machine manufacturer. . This prefor
The mouth plug part of the glass was heated and crystallized by a home-made mouth part crystallizer. Next, this preform was biaxially stretched and blown at a ratio 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 COPOPLAST Co., and subsequently about 150 times.
The container was heat-set in a mold set to 0 ° C. to form a container (body thickness 0.45 mm) having a capacity of 2000 cc. The stretching temperature was controlled to 100 ° C.

(15) Leakage Evaluation of Contents from Hollow Molded Body The hollow molded body molded in (14) above was filled with 90 ° C. hot water, capped with a capping machine, and then the container was laid down and left to stand. I investigated the leak. In addition, the state of deformation of the spout after capping was also examined.

(16) Cooling water in the chipping step and sodium content, calcium content, magnesium content, and silicon content in the introduced water of the water treatment step. After filtering with a 1G1 glass filter manufactured by Iwaki Glass Co., Ltd., the filtrate was measured with an inductively coupled plasma emission spectrometer manufactured by Shimadzu Corporation.

(17) Measurement of Number of Particles in Cooling Water in Water Chiping Process and Water Introduced During Water Treatment and Recycled Water Cooling water that has undergone particle removal and ion exchange, introduced water, or filtration device (5) and adsorption tower (8) ) The recycled water treated in (1) was measured using a particle measuring instrument PAC 150 manufactured by Seishin Enterprise Co., Ltd., which was a light blocking method, and the number of particles was expressed as 10/10 ml.

(18) Measurement of Number of Particles in Gas Contacting Polyester Chips The gas sent by a blower for forcibly sending the gas and passing through the gas cleaning device is branched from the main gas stream before coming into contact with the chips. Then, it is introduced into a particle measuring instrument and measured. The measurement is repeated 5 times, the average value is obtained, and the number per 1 cubic foot of gas is calculated. As the particle measuring instrument, a light scattering type particle measuring instrument KC-01B manufactured by Rion Co., Ltd. was used.

Example 1 A slurry of high-purity terephthalic acid and ethyl glycol was continuously supplied to a first esterification reactor containing a reactant in advance, and the slurry was stirred to about 2
The reaction was carried out at 50 ° C. and 0.5 kg / cm ² G for an average residence time of 3 hours. This reaction product was sent to the second esterification reactor and reacted under stirring at about 260 ° C. and 0.05 kg / cm ² to a predetermined degree of reaction. Further, crystalline germanium dioxide was heated and dissolved in water, ethylene glycol was added thereto, and a heat-treated catalyst solution and ethylene glycol solution of phosphoric acid were separately fed continuously to the second esterification reactor. . The esterification reaction product was continuously fed to the first polycondensation reactor and stirred at about 265 ° C. for 25 torr.
for about 1 hour and then in a second polycondensation reactor under stirring for about 26
Polycondensation was carried out at 5 ° C. and 3 torr for 1 hour, and further with stirring in the final polycondensation reactor at about 275 ° C. and 0.5 to 1 torr for 1 hour. The intrinsic viscosity of the melt polycondensation prepolymer is 0.5.
It was 4 dl / g.

The molten polycondensation reaction product was cooled with cooling water (sodium content 0.01 ppm, magnesium content 0.02).
ppm, calcium content is 0.01 ppm, silicon content is 0.08 ppm), chips are formed while cooling so that the chip temperature is about 40 ° C. or less, then transported to a storage tank, and then a vibrating sieving process. The fine content was reduced to about 20 ppm or less by removing fines and film-like substances in the airflow classification step. Then, it is sent to a crystallizer by a plug transport system, continuously crystallized at about 155 ° C. for 3 hours under nitrogen gas flow, then put into a tower-type solid-phase polymerization vessel and continuously at about 209 ° C. under nitrogen gas flow. Then, solid phase polymerization was carried out for about 15 hours to obtain a solid phase polymerized polyester. After the solid phase polymerization, fines and film-like substances were removed by continuous treatment in a sieving step and a fines removing step and stored in a storage tank.

The PET thus obtained had an intrinsic viscosity of 0.74 deciliter / gram, a DEG content of 2.6 mol%, a cyclic trimer content of 0.30% by weight, and an increased cyclic trimer content of 0. 40% by weight, the average density is 1.020 g / cm ³ ,
As (T / G) and Ac (T / G) of the chip are 7.10, 8.20, As (T / G) / Ac (T / G), respectively.
Was 0.87, the AA content was 2.6 ppm, the fine content was about 50 ppm, and the peak temperature on the highest side of the melting peak temperature was 245 ° C. The residual Ge amount measured by atomic absorption spectrometry was 51 ppm, and the residual P amount was 33 ppm.
It was ppm.

Linear low density polyethylene (MI = about 0.
A PET composition was obtained by dry blending with PET obtained at 9 g / 10 minutes and a density of about 0.923 g / cm ³ ) to about 10 ppb. From this, a molded plate and a biaxially stretched molded bottle were obtained by the methods (13) and (14). The results are shown in Table 1.

The haze of the molded plate was 4.2%, the haze unevenness of the molded plate was 0.2%, the Tc1 of the molded plate was 163 ° C., the density of the plug part was 1.380 g / cm ³ , and the density deviation of the plug part was 0.00
The value was 2 g / cm ³ and there was no problem. In addition, in the leak test of the contents, there was no problem and the mouth plug was not deformed.
The body haze of the obtained bottle was as good as 1.0%. The AA content of the bottle was 21.0 ppm, which was a value with no problem.

In the manufacturing process, all of the melt-polymerized prepolymer chips and the solid-phase polymerized chips were transported by the plug-type transportation system, and the chips were extracted from the reactor and the storage layer by the screw-type feeder. The same applies to Examples 2 and 3. Also, melt polycondensation PET chips and solid-state polymerization PE
JIS B 990 is used as the air that comes into contact with the T-chip before the T-chip is filled into a shipping container or a storage container and stored.
8 (1991) type 3 PET non-woven filter unit equipped with an air cleaner and JIS B 9908
HEP with (1991) type 1 particle collection rate of 99% or more
Air filtered by an air cleaner equipped with the A filter unit (the number of particles having a particle size of 0.3 to 5 μm is about 500 / cubic foot) was used. The same applies to Example 2 and Example 3.

(Example 2) The solid-state polymerization PET obtained in Example 1 before the contact with PE was treated with water as follows. Raw material chip supply port (1) in the upper part of the treatment tank, overflow discharge port (2) located at the upper limit level of the treated water in the treatment tank, and discharge port (3) of the mixture of polyester chips and treated water in the lower part of the treatment tank. ), The treated water discharged from the overflow discharge port and the treated water discharged from the discharge port at the lower part of the processing tank through the polyester chip drainer (4) are continuous filters having a filter medium of paper. -Pipe (6) sent again to the water treatment tank via the fine filtration removal device (5) and the adsorption tower (8), GAF filter made by ISP-bag PE-1P2S (polyester felt, filtration accuracy 1 μm) ) Is a water removing port (7) which is obtained by introducing new ion-exchanged water from outside the system through an in-water particle removing device and an ion-exchange device into an inlet (9) in the middle of this pipe (6). ) Equipped with a capacity of 50m ³ Of the tower type of polyethylene terephthalate (hereinafter,
Abbreviated as PET) Chips were continuously treated with water.

The above solid-state polymerized PET chips were treated by a vibrating sieving process and an airflow classifying process to adjust the content of fine and film-like substances to about 40 ppm, and then the treated water temperature was controlled to 95 ° C. Water was continuously supplied from the supply port (1) at the upper part of the treatment tank, and the water treatment was performed while continuously extracting PET chips together with the treated water from the discharge port (3) at the lower part of the water treatment tank at a water treatment time of 3 hours. The content of particles having a particle size of 1 to 25 μm in the introduced water sampled before the ion-exchanged water inlet (9) of the above-mentioned treatment apparatus was about 480 particles / 10 ml, the sodium content was 0.02 ppm, and the magnesium content was 0. 02ppm, calcium content 0.03pp
m, the silicon content was 0.08 ppm, and the number of particles of the recycled water after the treatment in the filtration device (5) and the adsorption tower (8) having a particle size of 1 to 40 μm was about 18,000 particles / 10 ml.

After the water treatment, the product was continuously dried with heated dry air, and subsequently treated in a vibrating sieving process and an airflow classifying process to remove fines and film-like substances, and the total content thereof was adjusted to about 45 ppm. . Increase of cyclic trimer is 0.0
The peak temperature on the highest side of the melting peak temperature of 3% by weight, Fine, etc. was 245 ° C.

The obtained PET had an intrinsic viscosity of 0.74 deciliter / gram, a DEG content of 2.7 mol%, a cyclic trimer content of 0.31 wt%, and As (T / T / T) of chips.
G) is 7.20, Ac (T / G) of the chip is 8.25,
As (T / G) / Ac (T / G) is 0.87, average density is 1.403 g / cm ³ , AA content is 2.6 ppm,
The fine content was about 50 ppm.

A PET composition was obtained by the same method as in Example 1. The PET composition was evaluated using a molded plate and a biaxially stretched molded bottle. The results are shown in Table 1.
Molded plate haze is 4.0%, molded plate haze unevenness is 0.2
%, Tc1 is 162 ° C., the density of the spout is 1.380 g /
cm ³ and the density deviation of the plug portion were 0.001 g / cm ^3, which were no problem, and the transparency of the bottle was 1.1%, which was good. In addition, in the leak test of the contents, there was no problem and the mouth plug was not deformed. AA content of bottle is 16.0pp
It was a value with no problem with m. After continuous stretching blow molding of 5000 or more bottles, no mold stain was observed and the transparency of the bottle was good.

Example 3 A melt polycondensation prepolymer having a low intrinsic viscosity obtained by shortening the melt polycondensation time as compared with Example 1.
Was used, and the solid-state polymerization PE was performed under the same conditions as in Example 1 except that the solid-state polymerization time was extended by about 5 hours.
T. and then PET in the same manner as in Example 1.
A composition was obtained. Table 1 shows the characteristics of the obtained PET composition, the molded plate molded from the PET composition, and the biaxially stretch-molded bottle.
The result was fine.

Comparative Example 1 The prepolymer melt-polycondensed in the same manner as in Example 1 was made into chips while cooling with cooling water of the same quality, and the chip temperature was raised to about 65 ° C. or higher to remove fines. Instead, they were transported to a temporary storage silo by the low-density transportation method. Then, this was put into a rotary heating tumbler, and after crystallization under reduced pressure, 210
Solid-state polymerization at 0 ° C, intrinsic viscosity 0.75 deciliter / gram, DEG content 2.7 mol%, cyclic trimer content 0.30% by weight, chip As (T / G) 9.9
0, Ac (T / G) of the chip is 8.40, As (T / G)
G) / Ac (T / G) is 1.18 and the average density is 1.40.
PET having 4 g / cm ³ and an AA content of 3.5 pm was obtained. It should be noted that even after the solid phase polymerization, the removal treatment of fine particles was not performed. The transportation to the solid-state polymerization apparatus and the transportation after the solid-state polymerization were all performed by the low-density transportation method. The chip temperature during transportation or immediately after transportation increased to about 70 ° C or higher. Then
The amount of linear low density polyethylene is about 60,000 pp
P by the same method as in Example 1 except that m
An ET composition was obtained. Table 1 shows the characteristics of the obtained PET composition, the molded plate molded from the PET composition, and the biaxially stretch-molded bottle. The transparency of the obtained bottle was poor, the thickness variation was very large, and the deformation of the spout and the leakage of the contents were examined, but the contents were leaked.

[0152]

[Table 1]

[0153]

According to the polyester composition of the present invention,
It has excellent crystallization controllability during melt molding and long-term continuous moldability, and the hollow molded article, sheet-like material and stretched film obtained therefrom have excellent transparency and heat-resistant dimensional stability. The shrinkage rate of the plug portion of the hollow molded body is in an appropriate range, and residual off taste and offensive odor hardly occur when the liquid container is formed.

[Brief description of drawings]

FIG. 1 is a schematic view of a water treatment device used in an example.

[Explanation of symbols] 1 raw material chip supply port 2 overflow discharge port 3 discharge port for polyester chips and treated water 4 drainer 5 fines removal device 6 piping 7 recycled water or / and ion exchanged water inlet 8 Adsorption tower 9 Ion exchange water inlet

Front page continuation (51) Int.Cl. ⁷ identification code FI theme code (reference) C08L 77:00 C08L 77:00 59:00) 59:00 (72) Inventor Shumu Kimura 26 Akao-cho, Otsu City, Shiga Prefecture No. 21 (72) Inventor Yoshitaka Eto 20F term of 248 Takagi, Shiga-cho, Shiga-gun, Shiga (reference) 4F070 AA13 AA15 AA42 AA47 AA54 DA11 DA12 4F071 AA14 AA15 AA19 AA20 AA46 AE22 AF30 AF45 AH04 AH05 BA01 BB05 BB05 BB05 BC01 BB05 4J002 BB002 BB032 BB042 BB052 BB062 BB072 BB082 BB122 BB142 BB162 BB172 CB002 CF061 CL012 CL032 GG00 GG01

Claims (8)

[Claims] 1. A solid-state polymerized polyester whose main repeating unit is ethylene terephthalate, and at least one resin selected from the group consisting of a polyolefin resin, a polyamide resin and a polyacetal resin, 0.1 ppb-500.
An absorption band (T) derived from a trans structure produced by internal rotation about the carbon-carbon bond of an ethylene glycol unit in an infrared absorption spectrum, Area intensity ratio As (T / G) on the surface of the chip between the absorption band (G) originating in the gosh structure and the area intensity ratio As (T / G) and the area intensity ratio Ac ( T / G) ratio As (T / G) / A
A polyester composition characterized in that c (T / G) is a chip satisfying the following formulas (1) and (2). 4.00 ≤ As (T / G) ≤ 9.00 (1) 0.60 ≤ As (T / G) / Ac (T / G) ≤ 0.99 (2) (where As (T / G G) is an absorption band (T) derived from the trans structure and an absorption band (G) derived from the gosh structure, which are generated by internal rotation around the carbon-carbon bond of the ethylene glycol unit in the infrared absorption spectrum. Shows the area intensity ratio on the chip surface, and Ac (T / G) is an absorption band derived from a trans structure generated by internal rotation around the carbon-carbon bond of the ethylene glycol unit in the infrared absorption spectrum. (T)
And the area intensity ratio of the absorption band (G) derived from the gosh structure at the center of the chip. ) 2. The polyester composition according to claim 1, wherein the fine content of the polyester having the same composition as the polyester is 0.1 to 5000 ppm. 3. The polyester composition according to claim 1, wherein the content of a film-like material having the same composition as that of the polyester is 10 ppm or less. 4. The polyester composition according to claim 1, wherein the peak temperature of the finest melting peak temperature is 265 ° C. or lower. 5. The polyester, in a chipping step after melt polycondensation, has a sodium content (N), a magnesium content (M), a silicon content (S) and a calcium content (C). Is a polyester chipped with cooling water satisfying at least one of the following (3) to (6), and the polyester composition according to any one of claims 1 to 4. N ≤ 1.0 (ppm) (3) M ≤ 0.5 (ppm) (4) S ≤ 2.0 (ppm) (5) C ≤ 1.0 (ppm) (6) 6. The polyester composition according to claim 1, wherein the amount of cyclic trimer increase when melted at a temperature of 290 ° C. for 60 minutes is 0.50% by weight or less. . 7. A polyester molded article obtained by molding the polyester composition according to any one of claims 1 to 8. 8. A polyester molded product, wherein the polyester molded product is a hollow molded product, a sheet-shaped product, or a stretched film obtained by stretching the sheet-shaped product in at least one direction. .