MXPA97007016A

MXPA97007016A - Polyesters, polyester compositions, polyester laminates and processes to produce polyester bottles biaxally stretch

Info

Publication number: MXPA97007016A
Application number: MXPA/A/1997/007016A
Authority: MX
Inventors: Nakamachi Koji; Masahiro Kouya; Hiraoka Shoji
Original assignee: Mitsui Petrochemical Industries Ltd
Priority date: 1996-02-21
Filing date: 1997-09-12
Publication date: 1998-07-03

Abstract

The novel polyester (first polyester [A]) of the invention comprises dicarboxylic acid constituent units derived from at least one dicarboxylic acid selected from the group consisting of terephthalic acid, isophthalic acid and naphthalene dicarboxylic acid, and diol constituent units derived from from diols comprising ethylene glycol and a polyalkylene glycol having an alkylene chain of 2 to 10 carbon atoms, wherein the proportion of constituent units derived from the polyakylene glycol is from 0.001 to 10 weight percent, based on the constituent units of diol. The polyester [A] has an excellent crystallization index, is suitably used individually or as compositions together with another polyester [B] and / or other polymers, for the production of molded products such as films, sheets, preforms and bottles, which have properties Excellent gas barrier, transparency and heat resistance. The polyester composition of the invention comprises from 1 to 99 weight percent of the first polyester [A] and from 1 to 99 weight percent of the second polyester [B], a polyamide and / or a polyolefin. The polyester laminate of the invention has a multilayer structure comprising a first resin layer of the first polyester [A] to the composition, and a second resin layer of another polyester [B], a polyamide and / or a polyolefin . The process to produce a biaxially stretched bottle comprises the steps of producing a preform from the first polyester [A], the composition or the polyester laminate, heating it, subjecting it to blow molding with biaxial stretching, to give a stretched bottle and retain the bottle in a mold, at a temperature of not less than 100

Description

POLYESTERS POLYESTER COMPOSITIONS, POLYESTER LAMINATES AND PROCESSES TO PRODUCE BOTTLES OF POLYESTER BIAXALLY STRETCHED.

TECHNICAL FIELD The present invention relates to novel polyesters, polyester compositions, polyester laminates and processes for producing biaxially oriented polyester bottles. More particularly, the invention relates to polyesters and polyester compositions, which have a high crystallization index, excellent gas barrier properties, transparency and heat resistance, and also relates to preforms, biaxially oriented bottles and. laminates, which are produced from polyesters, and with processes for producing biaxially oriented polyester bottles having excellent gas barrier, transparency and heat resistance properties.

PREVIOUS TECHNIQUE Because of its excellent gas barrier, transparency and mechanical strength properties, saturated polyesters such as polyethylene terephthalate are widely used for containers such as bottles. Particularly, the bottles obtained by blow molding of biaxial orientation of polyethylene terephthalate they are excellent in transparency, mechanical strength, heat resistance, and gas barrier properties, such that they have been used extensively for containers (PET bottles) to be filled with beverages such as juice, soft drinks and carbonated beverages. These bottles are generally produced by a process comprising the steps of molding the saturated polyester to give a preform having a neck and a body, then inserting the preform into a mold of a given shape, and subjecting the body of the preform to molding by blown with stretch, producing by the same bottles, each of these having a neck and a stretched body. Polyester bottles are required. particularly polyester bottles for beverages such as juice, have a heat resistance high enough for heat sterilization of the contents. Therefore, generally the bottles are further subjected to heat treatment (heat set) after blow molding, to improve the heat resistance. However, the collars of the polyester bottles obtained above do not stretch and are inferior to the bodies in heat resistance. In general, therefore, the collars of the preforms are crystallized by heat before blow molding, or the collars of the bottles obtained by blow molding are crystallized by heat, which improves the mechanical resistance and heat resistance of the necks. In recent years, sizes of bottles produced from polyester resins (particularly polyethylene terephthalate) tend to be made smaller. In the case of small-sized bottles, the content has an increased area in contact with the body of the bottle per unit volume of the content, and consequently a considerable loss of gas in the content occurs, or an oxygen transmission from the outside, which affects the content, resulting in a decrease in the shelf life of the content. In accordance with the foregoing, the development of polyester bottles which have better gas barrier properties than conventional ones is desirable. Recently, in addition, we want to reduce the time to produce polyester resin bottles, to improve productivity. In order to reduce the time for the production of bottles, it is effective to reduce the crystallization time of the collars, or the thermofixing time of the bottle bodies. However, reducing the crystallization time of the collars, or the thermofixing time of the bottle bodies, generally causes the decrease of the mechanical resistance or the heat resistance of the resulting bottles. Therefore, with the object of carrying out the crystallization of the collars or the vessel from the bodies of the bottles for a short period of time, it is necessary to use polyesters having a high crystallization index. As an example of the polyester having a high crystallization index, a polyester resin composition composed of a virgin polyester and a repro-polyester is known. The term "virgin polyester" used herein means a polyester prepared from a dicarboxylic acid and a diol, and has not passed through a molding machine in a molten state to give any bottle or preform. The term "repro-polyester" used herein means a polyester obtained by passing the virgin polyester in a molten state, through a molding machine at least once, and by spraying the resulting molded polyester product. Although some polyester resin compositions have a high crystallization index, and are capable of being crystallized by heat for a short period of time, the resulting bottles have a problem of decrease in transparency. In accordance with the foregoing, it has been desired to develop polyesters capable of producing molded articles, such as bottles, having excellent gas barrier and transparency properties. The development of biaxially stretched preforms and bottles is also desired, and of processes to produce biaxially stretched polyester bottles made from these polyesters.

OBJECTIVE OF THE INVENTION The present invention has been made under the circumstances mentioned above, and it is an object of the invention to provide a polyester and a polyester composition, both having a high crystallization index and having gas barrier, transparency and resistance properties. excellent heat. It is another object of the invention to provide a preform made of the polyester mentioned above, and a biaxially stretched bottle, and a polyester laminate, both having excellent gas barrier properties, transparency and heat resistance. It is another object of the invention to provide a process for producing biaxially stretched polyester bottles, by which bottles with excellent gas barrier, transparency and heat resistance properties can be produced, and to provide a process for producing biaxially stretched polyester bottles, by means of which bottles with excellent gas barrier, transparency and heat resistance properties can be produced with high productivity.

DESCRIPTION OF THE INVENTION The novel polyester according to the invention (first polyester [A]) is a polyester comprising: constituent units of dicarboxylic acid derived from at least one dicarboxylic acid selected from the group consisting of terephthalic acid, isophthalic acid and naphthalenedicarboxylic acid, and diol constituent units derived from diols comprising ethylene glycol and polyalkylene glycol having an alkylene chain of 2 to 10 carbon atoms, wherein the proportion of constituent units derived from the Polyalkylene glycol is in the range of 0.001 to 10 weight percent, based on the constituent units of diol. The polyester composition, according to the invention, comprises: from 1 to 99 weight percent of the first polyester [A], and from 1 to 99 weight percent of a second polyester [B] comprising dicarboxylic acid constituent units derived from at least one dicarboxylic acid selected from the group consisting of terephthalic acid, isophthalic acid and naphthalenedicarboxylic acid, and diol constituent units derived from diols comprising ethylene glycol, wherein the proportion of constituent units derived from a polyalkylene glycol is less than 0.001 weight percent, based on the constituent units of diol. Each of the preform and the biaxially stretched bottle, according to the invention, comprises the first polyester [A]. The polyester laminate, according to the invention, has a multilayer structure comprising: [I] a first resin layer formed from the first polyester [A], or the polyester composition of the invention, and [II] ] a second resin layer formed from at least one resin selected from the group consisting of (a) the second polyester [B], (b) a polyamide and (c) a polyolefin. The process for producing the biaxially stretched bottle, according to the invention, comprises the steps of producing a preform from the first polyester [A], the polyester composition or the polyester laminate, heating the preform, subjecting the preform to molding by blowing with biaxial stretching, to give a stretched bottle and retain the bottle stretched in a mold, at a temperature of not less than 100 ° C. In the above process, the neck of the preform can be crystallized by heat before blow molding with biaxial stretching, or the neck of the bottle can be heat crystallized, after blow molding with biaxial stretching.

BEST WAY TO CARRY OUT THE INVENTION The polyester (first polyester [A]), the preform and the biaxially stretched bottle made from the polyester, the polyester composition, the polyester laminate and the process for producing the biaxially fluted polyester bottle according to the invention.

First polyester TAI The first polyester. [A] novel according to the invention is a polyester comprising: constituent units of dicarboxylic acid derived from at least one dicarboxylic acid selected from the group consisting of terephthalic acid, isophthalic acid and naphthalenedicarboxylic acid, and constituent units of diol derived from of diols comprising ethylene glycol and polyalkylene glycol having an alkylene chain of 2 to 10 carbon atoms, wherein the proportion of constituent units derived from the polyalkylene glycol is in the range of 0.001 to 10 percent by weight. weight, based on the constituent units of diol. Subsequently, the constituent units of dicarboxylic acid and the constituent units of diol are described.

Dicarboxylic acid constituent unit in the first TAI polyester The dicarboxylic acid constituent units mainly contain constituent units derived from at least one dicarboxylic acid selected from the group consisting of terephthalic acid, isophthalic acid and naphthalenedicarboxylic acid, or its derivative ester (for example, lower alkyl ester, phenyl ester). (1) In the first preferred embodiment of the invention, the constituent units of dicarboxylic acid contain mainly constituent units derived from terephthalic acid or its ester derivative. In the constituent units of acid dicarboxylic, the constituent units derived from dicarboxylic acids other than terephthalic acid or its ester derivative, may be contained in amounts of not more than 15 mole percent. Examples of dicarboxylic acids other than terephthalic acid include: aromatic dicarboxylic acids, such as naphthalenedicarboxylic acid, diphenyldicarboxylic acid, and diphenoxyethedicarboxylic acid; aliphatic dicarboxylic acids, such as succinic acid, glutaric acid, adipic acid, sebacic acid, azelaic acid and decandicarboxylic acid; and alicyclic dicarboxylic acids, such as acid, cyclohexanedicarboxylic acid. The ester derivatives of the other dicarboxylic acids can also be used in addition to the terephthalic acid. These dicarboxylic acids and their ester derivatives can be used individually or in combination. (2) In the second preferred embodiment of the invention, the dicarboxylic acid constituent units contain mainly constituent units derived from terephthalic acid or its ester derivative, and contain constituent units derived from isophthalic acid or its ester derivative, in the specific proportion.

It is desired that the constituent units derived from the isophthalic acid or its ester derivative be contained in amounts of 1 to 15 weight percent, preferably 2 to 12 weight percent, more preferably 4 to 10 percent by weight, based on the constituent units of dicarboxylic acid. The first polyester containing constituent units derived from isophthalic acid in the amount of this range, has excellent heat stability in the molding process and excellent gas barrier properties. In the constituent units of dicarboxylic acid, constituent units derived from carboxylic acids other than terephthalic acid, al. Isophthalic acid or its ester derivatives may be contained in amounts of not more than 15 mole percent. Examples of dicarboxylic acids other than terephthalic acid and isophthalic acid include: aromatic dicarboxylic acids, such as o-phthalic acid, naphthalenedicarboxylic acid, diphenyldi-carboxylic acid, and diphenoxyethedicarboxylic acid; aliphatic dicarboxylic acids, such as succinic acid, glutaric acid, adipic acid, sebacic acid, azelaic acid and decandicarboxylic acid; and alicyclic dicarboxylic acids, such as cyclohexanedicarboxylic acid.

The ester derivatives of dicarboxylic acids other than terephthalic acid and isophthalic acid can also be used. These dicarboxylic acids and their ester derivatives can be used individually or in combination. (3) In the third preferred embodiment of the invention, the dicarboxylic acid constituent units mainly contain constituent units derived from naphthalenedicarboxylic acid or its ester derivative, and optionally contain constituent units derived from terephthalic acid or isophthalic acid or its ester derivatives. It is desired that the constituent units derived from the naphthalenedicarboxylic acid or its ester derivative be contained in amounts of 55 to 100 percent by weight, preferably 75 to 100 percent by weight, more preferably 85 to 99 percent by weight, based on the constituent units of dicarboxylic acid. The first polyester containing the constituent units derived from the naphthalenedicarboxylic acid in the amount of this range, has excellent heat stability in the molding process, and excellent gas barrier properties. In the constituent units of dicarboxylic acid, constituent units derived from dicarboxylic acids other than naphthalenedicarboxylic acid, terephthalic acid, acid isophthalic or its ester derivatives, may be contained in amounts of not more than 15 mole percent. Examples of the dicarboxylic acids, other than naphthalenedicarboxylic acid, terephthalic acid, and isophthalic acid include. aromatic dicarboxylic acids, such as o-phthalic acid, diphenyldicarboxylic acid and diphenoxyethane-dicarboxylic acid; aliphatic dicarboxylic acids, such as succinic acid, glutaric acid, adipic acid, sebacic acid, azelaic acid and decandicarboxylic acid; and alicyclic dicarboxylic acids, such as cyclohexanedicarboxylic acid. The ester derivatives of the dicarboxylic acids other than naphthalenedicarboxylic acid, terephthalic acid and isophthalic acid can also be used. These dicarboxylic acids and their ester derivatives can be used individually or in combination.

Diol constituent unit in the first polyester IAI The diol constituent units mainly contain constituent units derived from ethylene glycol and contain constituent units derived from polyalkylene glycol having a chain of alkylene of 2 to 10 carbon atoms in the specific proportion.

Polyalkylene Glycol Polyalkylene glycol having an alkylene chain of 2 to 10 carbon atoms, which forms the diol constituent units, is the generally known polyalkylene glycol. The polyalkylene glycols can be obtained by the condensation of an alkylene glycol of 2 to 10 carbon atoms, by a known method. The polyalkylene glycol desirably has a degree of polymerization (n) of 5 to 50, preferably 10 to 45, and has a molecular weight of 100 to 10,000, preferably, 200 to 5,000, particularly preferably 500 to 3,000. . Examples of polyalkylene glycols include polyethylene glycol, polypropylene glycol, polytetramethylene glycol, polyheptamethylene glycol, polyhexamethylene glycol, and polyoctamethylene glycol. Of these, polytetramethylene glycol is particularly preferred. In the present invention, it is desired that the constituent units derived from the polyalkylene glycol in the first polyester, are contained in amounts of 0.001 to 10 weight percent, preferably 0.01 to 8 weight percent, more preferably from 0.1 to 6 percent by weight, particularly preferably from 1 to 4 percent by weight weight, based on the constituent units of diol. If the amounts of the constituent units derived from the polyalkylene glycol are less than 0.001 weight percent, the improvement in the gas barrier properties, or the rate of crystallization by heating the polyester, may be insufficient. If the amounts thereof exceed 10 weight percent, the transparency, heat stability, and gas barrier properties of the polyester may be insufficient.

Other diols The diol constituent units may contain constituent units derived from diols, other than ethylene glycol and polyalkylene glycol having an alkylene chain of 2 to 10 carbon atoms, in amounts of not more than 15 percent in moles Examples of diols other than ethylene glycol and polyalkylene glycol include: aliphatic glycols, such as diethylene glycol, triethylene glycol, tetraethylene glycol, trimethylene glycol (propanediol), butanediol, pentanediol, neopentyl glycol, glycol hexamethylene and dodecarnetilene glycol; alicyclic glycols, such as cyclohexanedimethanol; and aromatic diols, such as bisphenols and hydroquinone. Ester derivatives of these diols can also be used. These diols and their ester derivatives can be used individually or in combination. The first polyester [A] of the invention can optionally contain constituent units derived from polyfunctional compounds, such as trimellitic acid, pyromellitic acid, trimethylolethane, trimethylolpropane, trimethylolmethane and pentaerythritol in small amounts, for example, not more than 2 percent by weight. moles The first polyester [A] of the invention can be prepared from the dicarboxylic acid and the diol mentioned above, by a known process. For example, the dicarboxylic acid and the diol are directly subjected to an esterification reaction, or when an alkyl ester of the dicarboxylic acid is used, the ester and the diol are subjected to an ester exchange reaction, and then the resulting ester is subjected to a melt polycondensation reaction, by heating the reaction mixture under reduced pressure to remove excess diol, by preparing the same first polyester [A]. These reactions can be carried out in the presence of conventionally known catalysts. Examples of the ester exchange catalysts include compounds of magnesium, manganese, titanium, zinc, calcium and cobalt. Examples of the polycondensation catalysts include antimony, germanium and titanium compounds. The ester exchange catalyst, or the polycondensation catalyst can be used in any amount, as long as the reactivity and heat resistance of the polyester are not decreased. In the polycondensation stage, phosphorus compounds can be added as stabilizers. Examples of the phosphorus compounds include phosphates, such as trimethyl phosphate, triethyl phosphate, tri-n-butyl phosphate, trioctyl phosphate and triphenyl phosphate, - phosphites, such as triphenyl phosphite, trisdodecyl phosphite phosphite trisnonyl, - acid phosphates, such as methyl acid phosphate, isopropyl acid phosphate, butyl acid phosphate, dibutyl acid phosphate, monobutyl phosphate, and dioctyl phosphate; and other phosphorus compounds, such as phosphoric acid and polyphosphoric acid. In the polycondensation reaction, the polycondensation catalyst is desirably used in an amount of 0.005 to 0.2 mole percent, preferably 0.001 to 0.1 mole percent, in terms of the metal atom in the catalyst, based on the acid dicarboxylic The first polyester [A] thus obtained has an intrinsic viscosity [IV] of 0.40 to 1.0 deciliters / gram, of preference of 0.50 to 0.90 deciliters / gram. The first polyester [A] obtained by the polycondensation reaction is generally extruded by melting into granules (flakes). The first polyester [A] obtained by the polycondensation reaction can also be subjected to a solid phase polycondensation reaction. For example, the polyester flakes obtained as described above can be polymerized in a solid phase at a temperature of not less than 160 ° C and lower than the melting point thereof, preferably from 170 to 220 ° C., for 8 to 40 hours, preferably 15 to 30 hours. The process for preparing the first polyester [A], including the esterification step and the polycondensation step, can be carried out batchwise or semicontinuously. The first polyester [A] is substantially linear, and this can be confirmed by the fact that the first polyester [A] is dissolved in o-chlorophenol. The first polyester [A] of the invention has an intrinsic viscosity [IV], as measured in o-chlorophenol at 25 ° C, usually 0.3 to 1.5 deciliters / gram, preferably 0.5 to 1.5 deciliters / gram. It is desirable that the first polyester [A] of the invention have an average crystallization time per heating from 10 to 200 seconds, preferably from 20 to 120 seconds. The average crystallization time by heating is measured by the method described below. To the first polyester [A] can be added different additives that are generally added to polyesters, such as dyes, antioxidants, ultraviolet light absorbers, antistatic agents, flame retardants and lubricants, if necessary. The first polyester [A] of the invention can be used as a molding material for different molded products such as preforms, bottles and films (stretched). The first polyester [A] of the invention has a high crystallization index. In the production of bottles, therefore, it is possible to reduce the time for heat crystallization of the necks of the preforms, or of the necks of the bottles, and consequently bottles with necks with resistance can be efficiently produced. excellent mechanical and heat resistance.

Preform and bottle The preform, according to the invention, can be obtained by, for example, injection molding or extrusion molding of the first polyester [A]. The bottle according to the invention can be obtained by blow molding with biaxial stretching of the preform, and then thermosetting the resulting molded product. In the preparation of the bottle, a neck of a preform can be heat crystallized, and then the preform can be blow molded with biaxial stretching, or a preform, before crystallization by heating its neck, it can be undergo blow molding with biaxial stretching, and then the neck of the bottle can be heat crystallized. It is desirable that the bottle of the invention have a rate of transmission of carbon dioxide gas in its body of generally not more than 17.5 cubic centimeters "millimeter / square meter" day »atm, preferably no more than 15 cubic centimeters »Millimeter / square meter» day «atm, more preferably no more than 4.0 cubic centimeters« millimeter / square meter »day» atm. In particular, when the bottle is made of the first polyester [A] in which the constituent units of dicarboxylic acid contain mainly constituent units derived from terephthalic acid or its ester derivative, the carbon dioxide gas transmission rate of preference is no more than 17.5 cubic centimeters "mm / square meter" day # atm. When the bottle is made of the first polyester [A] in which the constituent units of dicarboxylic acid contain mainly constituent units derived from terephthalic acid or its ester derivative, and in addition contain constituent units derived from isophthalic acid or its ester derivative, in the specific amount, The rate of carbon dioxide gas transmission is preferably no more than 15 cubic centimeters * mm / square meter * day »atm. When the bottle is made of the first polyester [A] in which the constituent units of dicarboxylic acid contain mainly constituent units derived from naphthalenedicarboxylic acid or its ester derivative, and in addition contain constituent-derived units from terephthalic acid or acid isophthalic or its ester derivatives, in the specific amount, the rate of transmission of carbon dioxide gas is preferably no more than 4.0 cubic centimeters »millime ro / square meter * atm * atm.

Polyester Composition The polyester composition according to the invention is described below. The polyester composition of the invention comprises: from 1 to 99 weight percent of the first polyester [A] comprising constituent dicarboxylic acid units derived from at least one dicarboxylic acid selected from the group consisting of terephthalic acid, isophthalic acid and naphthalenedicarboxylic acid, and diol constituent units derived from diols comprising ethylene glycol and polyalkylene glycol having an alkylene chain of 2 to 10 carbon atoms, wherein the proportion of constituent units derived from the polyalkylene glycol is the range of 0.001 to 10 weight percent, based on the constituent units of diol. from 1 to 99 weight percent of a second polyester [B] comprising constituents of dicarboxylic acid derived from at least one dicarboxylic acid selected from the group consisting of terephthalic acid, isophthalic acid and naphthalenedicarboxylic acid, and constituent diol units derived from diols comprising ethylene glycol, wherein the proportion of constituent units derived from a polyalkylene glycol is less than 0.001 weight percent, based on the diol constituent units.

Prjmer Qst? And [A] The first polyester [A] can be used as described above here.

Second polyester fBl The second polyester [B] is described below. The second polyester [B] comprises constituents of dicarboxylic acid derived from at least one dicarboxylic acid selected from the group consisting of terephthalic acid, isophthalic acid and naphthalenedicarboxylic acid, and diol constituent units derived from diols comprising a proportion of constituent units derived from a polyalkylene glycol, wherein the proportion of constituent units derived from a polyalkylene glycol is less than 0.001 weight percent, based on the constituent units of diol. The examples of the second polyester [B] are given below. (i) polyethylene terephthalate comprising dicarboxylic acid constituent units derived from a terephthalic acid or its ester derivative, and diol constituent units derived from ethylene glycol. In polyethylene terephthalate (i), the constituent units derived from other dicarboxylic acids and / or other diols, may be contained in amounts of less than 20 mole percent. Examples of other dicarboxylic acids include aromatic dicarboxylic acids, such as isophthalic acid, o-phthalic acid, and diphenyldicarboxylic acid and diphenoxyethanedicarboxylic acid, - aliphatic dicarboxylic acids, such as sebacic acid, azelaic acid and decanedicarboxylic acid; and alicyclic dicarboxylic acids, such as cyclohexanedicarboxylic acid. Examples of other diols include aliphatic glycols, such as diethylene glycol, trimethylene glycol, propylene glycol, tetramethylene glycol, hexamethylene glycol, dodecamethylene glycol, and polyalkylene glycols; alicyclic glycols, such as cyclohexanedimethanol; bisphenols, - and aromatic diols, such as hydroquinone and 2,2-bis (4- / 3-hydroxyethoxyphenyl) propane. (ii) Polyethylene naphthalate comprising dicarboxylic acid constituent units derived from naphthalenedicarboxylic acid or its ester derivative, and diol constituent units derived from ethylene glycol. In polyethylene naphthalate (ii), the constituent units derived from other dicarboxylic acids and / or other diols, may be contained in amounts of less than 40 mole percent. Examples of the other dicarboxylic acids include aromatic dicarboxylic acids, such as terephthalic acid, isophthalic acid, diphenyldicarboxylic acid, diphenylethericarboxylic acid, diphenoxyethane dicarboxylic acid, and dibromoterephthalic acid, aliphatic dicarboxylic acids, such as adipic acid, azelaic acid, sebacic acid and decandicarboxylic acid, alicyclic dicarboxylic acids, such as 1,4-cyclohexanedicarboxylic acid, cyclopropanedicarboxylic acid and hexahydroterephthalic acid; and hydroxycarboxylic acids, such as glycolic acid, p-hydroxybenzoic acid and p-hydroxyethoxybenzoic acid. Examples of other diols include propylene glycol, trimethylene glycol, diethylene glycol, tetramethylene glycol, pentamethylene glycol, hexamethylene glycol, decamethylene glycol, neopentylene glycol, polyalkylene glycols, p-xylene glycol, , 4-cyclohexanedimethanol, bisphenol A, p, p-diphenoxysulfone, 1,4-bis (β-hydroxyethoxy) benzene, 2,2-bis (p-jS-hydroxyethoxy-phenol) propane, p-phenylenebis (dimethylsiloxane) and glycerol . (iii) Copolymerized polyester comprising dicarboxylic acid constituent units and diol constituent units, derived from ethylene glycol, wherein the dicarboxylic acid constituent units contain mainly constituent units derived from terephthalic acid or its ester derivative, and also contain constituent units derived from iophthalic acid or its ester derivative in the specific proportion. It is desired that constituent units derived from isophthalic acid or its ester derivative be contained in amounts of 0.5 to 15 mole percent, preferably 0.5 to 10 mole percent, based on the constituent units of acid dicarboxylic in the copolymerized polyester (iii). (iv) Copolymerized polyester comprising dicarboxylic acid constituent units and diol constituent units, derived from ethylene glycol, wherein the dicarboxylic acid constituent units contain mainly constituent units derived from terephthalic acid or its ester derivative and also contain constituent units derived from naphthalenedicarboxylic acid or its ester derivative in the specific proportion It is desired that the constituent units derived from naphthalenedicarboxylic acid or its ester derivative be contained in amounts of 0.5 to 20 percent in moles, preferably from 0.5 to 10 mole percent, based on the constituent units of dicarboxylic acid in the copolymerized polyester (iv) (v) Copolymerized polyester comprising constituent units of dicarboxylic acid and diol constituent units, derived from glycol of ethylene, wherein the constituent units of dicarboxylic acid contain mainly constituent units derived from terephthalic acid or its ester derivative, and furthermore contain constituent units derived from adipic acid or its ester derivative in the specific proportion. It is desired that the constituent units derived from adipic acid or its ester derivative be contained in amounts of 0.5 to 15 mole percent, preferably 0.5 to 10 mole percent, based on the constituent units of acid dicarboxylic in the copolymer polyester (v). (vi) Copolymerized polyester comprising dicarboxylic acid constituent units derived from terephthalic acid or its ester derivative and diol constituent units, wherein the diol constituent units contain mainly constituent units derived from ethylene glycol and furthermore they contain constituent units derived from diethylene glycol in the specific proportion. It is desired that the constituent units derived from diethylene glycol be contained in amounts of 0.5 to 5 weight percent, preferably 1.0 to 3.0 weight percent, based on the constituent units of diol in the polyester of copolymer (vi). (vii) Copolymerized polyester comprising dicarboxylic acid constituent units derived from terephthalic acid or its ester derivative and diol constituent units, wherein the diol constituent units mainly contain constituent units derived from ethylene glycol and furthermore contain constituent units derived from neopentyl glycol in the specific proportion. It is desired that the constituent units derived from neopentyl glycol be contained in amounts of 1 to 30 percent by weight, preferably to 15 weight percent, based on the constituent units of diol in the copolymerized polyester (vii). (viii) Copolymerized polyester comprising dicarboxylic acid constituent units derived from terephthalic acid or its ester derivative and diol constituent units, wherein the diol constituent units contain mainly constituent units derived from ethylene glycol and furthermore contain constituent units derived from cyclohexane-dimethanol in the specific proportion. It is desired that the constituent units derived from the cyclohexanedimethanol be contained in amounts of 1 to 30 percent by weight, preferably 5 to 15 percent by weight, based on the units constituents of diol in the copolymerized polyester (viii). (ix) Copolymerized polyester comprising: constituents of dicarboxylic acid containing mainly constituent units derived from isophthalic acid or its ester derivative, and optionally containing constituent units derived from terephthalic acid or its ester derivative in the proportion specific, and diol constituent units containing constituent units derived from dihydroxyethoxylesol and constituent units derived from ethylene glycol. it is desired that constituent units derived from isophthalic acid be contained in amounts of 20 to 100 weight percent, preferably 50 to 98 weight percent, based on the constituent units of dicarboxylic acid in the copolymerized polyester ( ix). It is also desired that the constituent units derived from the dihydroxyethoxyol are contained in amounts of 5 to 90 mole percent, preferably to 85 mole percent, based on the constituent units of diol in the copolymerized polyester (ix). In the copolymerized polyester (ix), furthermore, the constituent units derived from a polyfunctional hydroxyl compound having at least three groups hydroxyl, are desirably present in amounts of 0.05 to 1.0 part in moles, preferably 0.1 to 0.5 parts by moles, based on 100 parts by moles of the constituent units of dicarboxylic acid. In the copolymerized polyesters (iii) to (ix), the constituent units derived from other dicarboxylic acids and / or other diols other than those mentioned above, the dicarboxylic acids and the diols may be contained in such quantities that the properties of the copolymer polyesters (iii) to (ix) are not broken, for example, in amounts of not more than 1 mole percent. Examples of other dicarboxylic acids include o-phthalic acid and 2-methylterephthalic acid. Examples of other diols include 1,3-propanediol, 1,4-butanediol, cyclohexanedi anol, 1,3-bis (2-hydroxyethoxy) benzene, 1,4-bis (2-hydroxyethoxy) benzene, 2,2-bis (4-β-hydroxyethoxyphenyl) propane and bis (4-β-hydroxyethoxyphenyl) sulfone. In the second polyester [B] used in the invention, the constituent units derived from polyfunctional compounds, such as trimellitic acid, trimethylolethane, trimethylolpropane, trimethylolmethane and pentaerythritol, may be contained in small amounts, for example, not more than 2. percent in moles. In the second polyester [B], in addition, the units constituents derived from polyfunctional compounds, such as benzoylbenzoic acid, diphenylsulfonmoncarboxylic acid, stearic acid, methoxypolyethylene glycol, and phenoxy polyethylene glycol, may be contained in amounts of not more than 2 mole percent. It is desired that the crystallization temperature (Te) by heating the second polyester [B], as measured by means of a differential scanning calorimeter (DSC) in which a sample is heated at a rate of 10 ° C / minute, is not less than 150 ° C, preferably 160 to 230 ° C, more preferably 170 to 220 ° C. The crystallization temperature (Te) can be measured by heating the polyesters described herein-in the following manner. About 10 milligrams of a sample flake is cut from the center of a flake of saturated polyester resin that has been dried at about 140 ° C under a pressure of about 5 milligrams of mercury, for not less than 5 hours. The sample is sealed in an aluminum tray for liquid in a nitrogen atmosphere. Using a differential scanning calorimeter, molded DSC-2, produced by Perkin Elmer Co., the measurement is performed under such conditions that the sample is heated rapidly from room temperature to 290 ° C, in which the sample is kept in a molten state, for 10 minutes, and then cooled quickly to the room temperature, and after that it is heated again at a speed of 10 ° C / minute to detect the exothermic peaks. The maximum peak temperature of these exothermic peaks was taken as the crystallization temperature (Te) by heating. The second polyester [B] has an intrinsic viscosity [IV], as measured in o-chlorophenol at 25 ° C, usually 0.5 to 1.5 deciliters / gram, preferably 0.6 to 1.2 deciliters / gram. The second polyester [B] can be prepared by a conventionally known process. The second polyester [B] can be used individually or as a mixture of two or more such polyesters. Examples of polyester blends include those of polyethylene terephthalate (i) and polyethylene naphthalate (ii), polyethylene terephthalate (i) and at least one of the copolymerized polyesters (iii) to (ix), and at least two of the copolymerized polyesters (iii) a (ix) Of the mixtures, the one that is preferably used is a mixture of polyethylene terephthalate (i) and copolymer polyester (iii), and a mixture of polyethylene terephthalate (i) and the copolymer polyester (ix). The polyester composition of the invention comprises: the second polyester [B] in an amount of 1 to 99 percent by weight, preferably 1 to 50 percent by weight, more preferably 98 to 75 percent by weight. When the polyester composition contains the first polyester [A] in the amount of the above range, the composition exhibits sufficiently increased gas barrier properties and a crystallization rate by heating, without decreasing the heat stability in the molding process. The polyester composition of the invention desirably has a mean crystallization time by heating from 10 to 400 seconds, preferably from 60 to 300 seconds. The mean crystallization time by heating is measured by the method described below. The polyester composition of the invention can be prepared from the first polyester [A] and the second polyester [B] by any process. For example, the first polyester [A] and the second polyester [B] are mixed directly by a mixing machine such as a smashing mixer or a Henschel mixer. Alternatively, the first polyester [A] and the second polyester [B] can be kneaded by melting previously, to prepare a masterbatch containing the first polyester [A] in a high concentration, and then added appropriately the second polyester [B] to the master batch. Various additives may be added to the polyester composition of the invention which are generally added to the polyesters, such as dyes, antioxidants, ultraviolet light absorbers, antistatic agents, flame retardants and lubricants, if necessary. These additives can be added to the polyester composition as a master batch previously prepared from the additives and the polyester composition. The polyester composition of the invention can be used as a molding material for different molded products such as preforms, bottles, films (stretched) and leaves for good transparency and ownership. barrier to the upper gas. The polyester composition of the invention has a high crystallization index. In the production of bottles, therefore, it is possible to decrease the time for heat crystallization of the necks of the preforms or the necks of the bottles, and consequently, bottles having resistance necks can be efficiently produced. excellent mechanical and heat resistance.

Polyester Laminate The polyester laminate, according to the invention, has a multilayer structure that comprising: [I] a first resin layer formed from the first polyester [A], or the polyester composition of the invention, and [II] a second resin layer formed from at least one resin selected from the group consisting of (a) the second polyester [B], (b) a polyamide and (c) a polyolefin.

Resin resin layer The second resin layer is formed from at least one resin selected from the group consisting of (a) the second polyester [B], (b) a polyamide and (c) a polyolefin. Subsequently, each resin is described. (a) Second polyester TBl In the present invention the second polyester [B] can be used, as described above in the polyester composition. (b) Polyamide Examples of the polyamide (b) include aliphatic polyamides, such as nylon 6, nylon 66, nylon 10, nylon 12, and nylon 46, and aromatic polyamides prepared from aromatic dicarboxylic acids and aliphatic diamines. Of these, nylon 6 is particularly preferred. These polyamides can be used individually or in combination. These polyamides can be prepared by conventional processes. (c) Polyolefin Examples of the polyolefin (c) include olefin homopolymers, such as polyethylene, polypropylene, poly-1-butene, polymethylpentene, polymethylbutene, and olefin copolymers, such as propylene / ethylene random copolymer. Of these, polyethylene and polypropylene are particularly preferred. - These polyolefins can be used individually or in combination. These polyolefins can be prepared by conventional processes. In the present invention, the second resin layer can be formed from a mixture of the above resins (a) to (c). The first resin layer and the second resin layer may contain different additives that are generally added to the resin layers, such as dyes, antioxidants, ultraviolet light absorbers, antistatic agents, flame retardants and lubricants, if necessary. In the polyester laminate of the invention, the first resin layer and the second resin layer are laminated together. It is desirable that the thickness ratio of the first resin layer is preferably in the range of 5 to 30 percent, more preferably 5 to 20 percent, more preferably 5 to 15 percent, and that the proportion The thickness of the second resin layer is preferably in the range of 70 to 95 percent, more preferably 80 to 95 percent, more preferably 85 to 95 percent, both based on the total thickness of the laminate. polyester. The polyester laminate of the invention may have a third layer in addition to the first and second resin layers. For example, the third layer may be a layer made of a composition comprising the resin for the formation of the first resin layer, and the resin for the formation of the second resin layer, or a layer containing additives such as stabilizers. thermal, weathering stabilizers, lubricants, dyes, pigments, anti-fog agents, antistatic agents, wherein each of the layers can be provided on at least one surface of the polyester laminate, or can be provided as an intermediate layer between the layers of first and second resin; a layer for bonding the first layer of resin to the second resin layer, such as a modified polyolefin layer; and also a layer made of glass, metal or paper. The laminate of the invention can be prepared in accordance with conventional processes, using the resins described above. The polyester composing the laminate of the invention has a high crystallization index. In the production of bottles, therefore, it is possible to reduce the time for the heat crystallization of the necks of the preforms or of the necks of the bottles, and consequently, bottles having resistance necks can be efficiently produced. excellent mechanical and heat resistance. When the laminate of the invention is in the form of a preform or a bottle, its outer layer is preferably the first resin layer. When the polyester laminate of the invention is in the form of a bottle, the body of the bottle has a carbon dioxide gas transmission rate of not more than 17.5 cubic centimeters * mm / square meter, preferably 15.0 cubic centimeters »Millimeter / square meter» day »atm, more preferably 4.0 cubic centimeters» millimeter / square meter «day» atm.

Process for the production of polyester bottle biaxially oriented The process for producing the biaxially stretched polyester bottle according to the invention is described below. In the process for producing the biaxially stretched bottle according to the invention, a preform is produced from either the first polyester [A], the polyester composition or the polyester laminate, the preform is heated, molded by blowing with biaxial stretching, and the resulting stretched bottle is kept in a mold at a temperature less than 100 ° C. The preform can be produced by a conventional molding method such as extrusion molding or injection molding. The preform formed from the polyester laminate can be produced by, for example, subjecting the first polyester [A] or the polyester composition of the invention to form the first resin layer and the resin to form the second resin layer at a co-extrusion molding to form a multilayer tube and then providing a bottom at one end of the tube and a neck at the other end of the tube. Alternatively, the aforementioned first resin layer or the composition and the second resin layer can be subjected to a co-injection molding to form a multilayer preform.

Preferably, the outer layer of the preform produced in this manner is the first resin layer. The proportion of the thickness of the first resin layer is in the range of, preferably 5 to 30 percent, more preferably 5 to 20 percent, most preferably 5 to 15 percent, based on the total thickness of the wall of the preform. The proportion of the thickness of the second resin layer is in the range of, preferably 70 to 95 percent, more preferably 80 to 95 percent, most preferably 85 to 95 percent, based on the total thickness of the wall of the preform. Since said preform can be stretched in a high proportion of stretch in the production of the bottle, the total length of the. The preform may be shorter than the conventional one, or the diameter of the preform may be smaller than the conventional one. In the above process, the temperature for heating the preform is desirably in the range of 70 to 150 ° C, preferably 80 to 140 ° C. The preform can be heated from the outside and the inside (hollow part). Infrared rays and the like can be used as sources of heat. Heating from the hollow part preferably takes place simultaneously with heating from the outside. In the biaxial stretch blow molding, the stretch ratio is 6 to 15 times, preferably 7 to 12 times, in terms of the stretch ratio of the area (proportion of longitudinal stretch x proportion of transverse stretch). In the present invention, the biaxially stretched bottle can be further subjected to heat settling. Settling by heat is performed in a desirable manner by holding the bottle oriented in a mold at a mold temperature of 100 to 240 ° C, preferably 110 to 220 ° C, particularly preferably 140 to 210 ° C, for a period of time. period of not less than 1 second, preferably not less than 3 seconds. By virtue of heat settling, the heat resistance and gas barrier properties of the stretched bottle are improved. In the present invention, the neck of the preform can be heat crystallized prior to blow molding with biaxial stretching, or the neck of the bottle can be heat crystallized after blow molding with biaxial stretching. The heat crystallization of the neck of the preform or of the neck of the bottle can be carried out at a temperature of 100 to 200 ° C, preferably of 120 to 180 ° C. It is desirable that the heat crystallization be carried out so that the neck of the preform or neck of the bottle has a crystallinity of 25 to 60 percent, preferably 25 to 50 percent. The body of the biaxially polyester bottle stretched has a carbon dioxide gas transmission rate of usually no more than 17.5 cubic centimeters »millimeter / me ro square» day »atm, preferably 15.0 cubic centimeters» millimeter / square meter »day» atm, most preferably 4.0 cubic centimeters »millimeter / square meter» day »atm. The biaxially stretched polyester bottle has an opacity of usually 1.0 to 20 percent, preferably 5 to 15 percent. In accordance with the process of the invention, the transparency of the body of the bottle is hardly harmed, and therefore a biaxially stretched polyester bottle having excellent transparency, gas barrier properties and heat resistance can be produced. In accordance with the process of the invention, further, heat crystallization of a neck of the preform or a neck of the bottle can be performed at a high speed, so that a cycle of molding of the bottle including the heat crystallization of the neck, and a biaxially stretched polyester bottle having excellent transparency, gas barrier properties and heat resistance can be produced with high productivity.

EFFECT OF THE INVENTION Polyester and novel polyester composition according to the invention, they exhibit a high crystallization rate and have excellent gas barrier, transparency and heat resistance properties. The polyester laminate according to the invention has excellent gas barrier, transparency and heat resistance properties. The polyester laminate is suitable for bottles and preforms. The bottles, sheets and films formed from the novel polyester, the polyester compositions and the polyester laminate according to the invention are suitable for bottles for soft drinks such as water, juice, cola and carbonated beverages, bottles for flavoring materials such as soy sauce, orcester sauce and tomato sauce, bottles for liquors such as wine, sake and whiskey, leaves for packaging or storing dairy products such as butter and cheese, meat and fish, tanks for agricultural chemicals or gasoline, and films of packaging for medicines. In accordance with the process of the invention, biaxially stretched polyester bottles showing excellent gas barrier properties, transparency and heat resistance and having high mechanical resistance and heat resistance and their necks can be produced with high productivity.

EXAMPLE The present invention will be further described with reference to the following examples, but it should be construed that the invention is not limited in any way by those examples. In the following examples, the properties were measured according to the methods described below.

Intrinsic viscosity fivi A sample solution of 8 grams / deciliter was prepared by dissolving the o-chlorophenol as a solvent and measuring for a solution viscosity at 25 ° C. The intrinsic viscosity was calculated from the viscosity of the solution. rate of transmission of carbon dioxide gas (gas barrier properties) The transmission rate of carbon dioxide gas was measured under the conditions of a 23 ° C and a relative humidity of 60 percent by means of a device measuring the transmission speed of carbon dioxide gas GPM-250 manufactured by G.L. Science. The films used in the measurement were produced as follows: The oriented film (2): A 0.1 mm thick film was produced by means of a pressure molding machine at a mold temperature of 290 ° C, and the film was rapidly cooled to a cooling mold temperature of 0. ° C to give an amorphous film (1). The amorphous film (1) was stretched biaxially at the same time at a stretch rate of 3 times in each direction at a higher temperature by 15 ° C than the glass transition temperature (Tg) of the polyester to form the amorphous film, to give a stretched film (2). Heat-mounted film (3): The stretched film (2) was mounted on a metal assembly, and the heat assembly was performed at 150 ° C for 3 minutes in an oven to give a heat-mounted film (3). Heat-mounted bottle (4): A preform was produced by means of an injection molding machine under the conditions of a cylinder temperature of 280 ° C and a mold temperature of 10 ° C. The preform was then subjected to a blow molding with biaxial stretching, first at a 3-fold longitudinal stretch index and then at a 3-fold transverse stretch index at a higher temperature by 15 ° C than the transition temperature at preform polyester glass, to produce a bottle. Heat the body of the bottle at 200 ° C for 1 minute to obtain a heat-mounted bottle with stretching (4). The body of the heat-mounted bottle (4) was cut to give a specimen.

Transparency (opacity) A dry polymer was molded into a square plate 5 millimeters thick by means of an injection molding machine under the conditions of a cylinder temperature of 280 ° C and a mold temperature of 10 ° C. The transparency of the molded square plate was evaluated by measuring an opacity value in accordance with the method of ASTM D 1003.

Mean crystallization time The average crystallization time was measured by means of a differential scanning calorimeter (DSC) manufactured by Perkin Elmer Co. A dry 10-milligram polymer was weighed and placed on a sample tray, heated to 290 ° C. C for 5 minutes to melt it, then cooled rapidly to 50 ° C at a cooling rate of 320 ° C / minute and allowed to rest for 5 minutes, to prepare an amorphous sample. The sample was again heated to 140 ° C at a heating rate of 320 ° C / minute and maintained at this temperature. The sample was crystallized at this temperature to give an exothermic time curve, from which obtained the total calorific value. The mean crystallization time is defined as the time (second) it takes to generate the heat in an amount of 1/2 of the total calorific value. As the polymer has a shorter crystallization time, the crystallization of the polymer proceeds more efficiently and the productivity of the bottle increases. The bottle obtained by the process to produce the heat-mounted bottle (4) was evaluated for heat resistance and appearance in accordance with the methods described below.

Heat Resistance A biaxially stretched bottle having an internal volume of 1.5 liters obtained as described above was allowed to remain at rest for 1 week under the conditions of a temperature of 40 ° C and a humidity of 90 percent. The bottle was filled with 90 ° C hot water and kept for 10 minutes. The internal volumes of the bottle were measured before and after filling with the hot water. From the internal volumes measured in this way, a degree of shrinkage (%) was calculated by the following equation.

Degree of shrinkage (%) = A (g) - B (g) x 100 A (g) A: internal volume before filling with hot water B: internal volume after filling with hot water Heat resistance was evaluated by means of the shrinkage degrees (%) based on the following criteria. AA: 0 = degree of shrinkage (%) < 0.5 BB: 0.5 = degree of shrinkage (%) Appearance of the bottle The opacity of the lateral surface of a biaxially stretched bottle having an internal volume of 1. 5 liters obtained as described above in the position of 83 millimeters in height from the bottom of the bottle. The appearance of the bottle was evaluated by opacity (%) based on the following criteria. AA: 0 = opacity (%) < 5 BB: 5 = opacity (%) Example 1 A polyester having a viscosity was prepared Intrinsic [IV] of 0.775 deciliters / gram in accordance with a conventional method by using 166 parts by weight of terephthalic acid (a-1), as a component of dicarboxylic acid (a), and 68 parts by weight of glycol of ethylene (b-1) and 1.9 parts by weight of polytetramethylene glycol (b-2) having an average molecular weight of 1,000, as components of the diol (b). As for the polyester, the opacity, the glass transition temperature, the average crystallization time and the carbon dioxide gas transmission rate, were measured by the methods mentioned above. In the Table 1 shows the results.

Example 2 A polyester having an intrinsic viscosity [IV] of 0.780 deciliters / gram was obtained in the same manner as in Example 1, except that the polytetramethylene glycol (b-2) having an average molecular weight of 1,000 was replaced with a polytetramethylene glycol (b-3) that had an average molecular weight of 2,000. As for the polyester, the opacity, the glass transition temperature, the average crystallization time and the carbon dioxide gas transmission rate, were measured by the methods mentioned above. The results are shown in Table 1.

Example 3 A polyester having an intrinsic viscosity [IV] of 0.778 deciliters / gram was obtained in the same manner as in Example 1, except that the polytetra-methylene glycol (b-2) having an average molecular weight of 1,000 , was replaced with a polytetramethylene glycol (b-4) having an average molecular weight of 2,900. As for the polyester, the opacity, the glass transition temperature, the average crystallization time and the carbon dioxide gas transmission rate, were measured by the methods mentioned above. In the Table 1 shows the results.

Comparative Example 1 A polyester having an intrinsic viscosity [IV] of 0.775 deciliters / gram was obtained by using 166 parts by weight of terephthalic acid (a-1), as a component of dicarboxylic acid (a), and 68 parts by weight of ethylene glycol (b-1) as a component of the diol (b). As for the polyester, the opacity, the glass transition temperature, the average crystallization time and the carbon dioxide gas transmission rate, were measured by the methods mentioned above. The results are shown in Table 1.

Comparative Example 2 A polyester having an intrinsic viscosity [IV] of 0.776 deciliters / gram was obtained by using 166 parts by weight of terephthalic acid (a-1), as a component of dicarboxylic acid (a), and 68 parts by weight of ethylene glycol (b-1) and 8.5 parts by weight of polytetramethylene glycol (b-2) having an average molecular weight of 1,000, as components of the diol (b). As for the polyester, the opacity, the glass transition temperature, the average crystallization time and the carbon dioxide gas transmission rate, were measured by the methods mentioned above. The results are shown in Table 1.

Table 1 (I) Table 1 (II) Example 4 A polyester having an intrinsic viscosity [IV] of 0.775 deciliters / gram was obtained by using 148 parts by weight of terephthalic acid (a-1), and 16 parts by weight of isophthalic acid (a-2) as components of dicarboxylic acid (a), and 68 parts by weight of ethylene glycol (b-1) and 1.9 parts by weight of polytetramethylene glycol (b-2) having an average molecular weight of 1,000, as components of the diol (b). As for the polyester, the opacity, the glass transition temperature, the mean crystallization time and The transmission rate of carbon dioxide gas was measured by the methods mentioned above. The results are shown in Table 2.

Example 5 A polyester having an intrinsic viscosity [IV] of 0.780 deciliters / gram was obtained in the same manner as in Example 4, except that the polytetramethylene glycol (b-2) having an average molecular weight of 1,000 was replaced with a polytetramethylene glycol (b-3) that had an average molecular weight of 2,000. As for the polyester, the opacity, the glass transition temperature, the mean crystallization time? The transmission rate of carbon dioxide gas was measured by the methods mentioned above. In the Table 2 shows the results.

Example 6 A polyester having an intrinsic viscosity [IV] of 0.778 deciliters / gram was obtained in the same manner as in Example 4, except that the polytetramethylene glycol (b-2) having an average molecular weight of 1,000 was replaced with a polytetramethylene glycol (b-4) having an average molecular weight of 2,900. As for polyester, opacity, temperature of transition to glass, the mean crystallization time and the rate of transmission of carbon dioxide gas, were measured by the methods mentioned above. The results are shown in Table 2.

Example 7 A polyester having an intrinsic viscosity [IV] of 0.775 deciliters / gram was obtained by using 158 parts by weight of terephthalic acid (a-1), and 8 parts by weight of isophthalic acid (a-2) as components of the dicarboxylic acid (a), and 68 parts by weight of ethylene glycol (b-1) and 1.9 parts by weight of polytetramethylene glycol (b-2) ) having an average molecular weight of 1,000, as "components of the diol (b)." Regarding polyester, opacity, glass transition temperature, mean crystallization time and the rate of transmission of carbon dioxide gas , were measured by the methods mentioned above, and the results are shown in Table 2.

Comparative Example 3 A polyester having an intrinsic viscosity [IV] of 0.775 deciliters / gram was obtained by using 133 parts by weight of terephthalic acid (a-1), and 33 parts by weight of isophthalic acid (a-2) as components of the acid dicarboxylic (a), and 68 parts by weight of ethylene glycol (b-1) and 1.9 parts by weight of polytetramethylene glycol (b-2) having an average molecular weight of 1,000, as components of the diol (b). As for the polyester, the opacity, the glass transition temperature, the average crystallization time and the carbon dioxide gas transmission rate, were measured by the methods mentioned above. The results are shown in Table 2. ib Table 2 (I) fifteen Table 2 (II) Example 8 A polyester [Al] having an intrinsic viscosity [IV] of 0.643 deciliters / gram was obtained by using 198 parts by weight of naphthalenedicarboxylic acid (a-3), and 16 parts by weight of isophthalic acid (a- 2) as components of the dicarboxylic acid (a), and 68 parts by weight of ethylene glycol (b-1) and 1.9 parts by weight of polytetramethylene glycol (b-2) having an average molecular weight of 1,000, as components of the diol (b). As for the polyester, the opacity, the glass transition temperature, the mean crystallization time and The transmission rate of carbon dioxide gas was measured by the methods mentioned above. The results are shown in Table 3.

Example 9 A polyester [A-2] having an intrinsic viscosity [IV] of 0.648 deciliters / gram was obtained in the same manner as in Example 8, except that the polytetramethylene glycol (b-2) having a molecular weight average of 1,000, was replaced with a polytetramethylene glycol (b-3) having an average molecular weight of 2,000. As for the polyester, the opacity, the glass transition temperature, the mean crystallization time and. The transmission rate of carbon dioxide gas was measured by the methods mentioned above. In the Table 3 shows the results.

Example 10 A polyester having an intrinsic viscosity [IV] of 0.648 deciliters / gram was obtained in the same manner as in Example 8, except that the polytetramethylene glycol (b-2) having an average molecular weight of 1,000. it was replaced with a polytetramethylene glycol (b-4) having an average molecular weight of 2,900. As for polyester, opacity, temperature of transition to glass, the mean crystallization time and the rate of transmission of carbon dioxide gas, were measured by the methods mentioned above. The results are shown in Table 3.

Example 11 A polyester [A-3] having an intrinsic viscosity [IV] of 0.622 deciliters / gram was obtained by the use of 206 parts by weight of naphthalenedicarboxylic acid (a-3), and 8 parts by weight of isophthalic acid ( a-2) as components of the dicarboxylic acid (a), and 68 parts by weight of ethylene glycol (b-1) and 1.9 parts by weight of polytetramethylene glycol (b-2) having an average molecular weight of 1,000 , as components of the diol (b). As for the polyester, the opacity, the glass transition temperature, the average crystallization time and the carbon dioxide gas transmission rate, were measured by the methods mentioned above. The results are shown in Table 3.

Axis-plp 12 A polyester [A-4] having an intrinsic viscosity [IV] of 0.613 deciliters / gram was obtained by the use of 214 parts by weight of naphthalenedicarboxylic acid (a-3), as a component of the dicarboxylic acid ( a), and 68 parts by weight of ethylene glycol (b-1) and 1.9 parts by weight of polytetramethylene glycol (b-2) having an average molecular weight of 1,000, as components of the diol (b). As for the polyester, the opacity, the glass transition temperature, the average crystallization time and the carbon dioxide gas transmission rate, were measured by the methods mentioned above. The results are shown in Table 3.

Comparative Example 4 A polyester having an intrinsic viscosity [IV] of 0.673 deciliters / gram was obtained by the use of 214 parts by weight of naphthalenedicarboxylic acid (a-3), as "one component of the dicarboxylic acid (a), and 68 parts by weight of ethylene glycol (b-1) and 8.5 parts by weight of polytetramethylene glycol (b-) 2) that had an average molecular weight of 1,000, as components of the diol (b) .As for the polyester, the opacity, the glass transition temperature, the average crystallization time and the transmission rate of carbon dioxide gas , were measured by the methods mentioned above.

Table 3 shows the results.

Example 5 Compound A polyester having a viscosity was obtained Intrinsic [IV] of 0.619 deciliters / gram by using 214 parts by weight of naphthalenedicarboxylic acid (a-3), as a component of dicarboxylic acid (a), and 68 parts by weight of ethylene glycol (b-1) ) as a component of diol (b). As for the polyester, the opacity, the glass transition temperature, the average crystallization time and the carbon dioxide gas transmission rate, were measured by the methods mentioned above. The results are shown in Table 3.

Table 3 (I) Table 3 (II) Example 13 The polyester [Al] of Example 8 was used as a first polyester and a second polyester [Bl] (polyethylene terephthalate, diethylene glycol content: 1.95 weight percent, intrinsic viscosity [IV]: 0.835 deciliters / gram) ) at a weight ratio of 5: 95 ([Al]: [Bl]), for prepare a polyester composition. The polyester composition was md and injection md into a square plate, a film and a bottle in the manner described above. Then, the opacity, the average crystallization time, the carbon dioxide gas transmission rate, the heat resistance and the appearance of the bottle were evaluated by the methods mentioned above. The results are shown in Table 4.

Example 14 A polyester composition was prepared in the same manner as in Example 13, except that the weight ratio of [A-1] to [B-1] was varied to 10: 90. They evaluated the properties by the methods mentioned above. The results are shown in Table 4.

Example 15 A polyester composition was prepared in the same manner as in Example 13, except that the weight ratio of [A-1] to [B-1] was varied to 15:85. The properties were then evaluated by the methods mentioned above. The results are shown in Table 4.

Example 16 A polyester composition was prepared in the same manner as in Example 13, except that the polyester [A-2] of Example 9 was used in place of the polyester [A-1]. Then, the properties were evaluated by the methods mentioned above. The results are shown in Table 4.

Example 17 A polyester composition was prepared in the same manner as in Example 13, except that the polyester [A-2] was used instead of the polyester [Al], and the weight ratio of [A-2] to [ Bl] was made from 10: 90. Then, the properties were evaluated by the methods mentioned above, and the results are shown in Table 4.

Example 18 A polyester composition was prepared in the same manner as in Example 13, except that the polyester [A-2] was used instead of the polyester [Al], and the weight ratio of [A-2] to [ Bl] was made from 15: 85. Then, the properties were evaluated by the methods mentioned above. The results are shown in Table 4.

Example 19 A polyester composition was prepared in the same manner as in Example 13, except that the polyester [A-3] of Example 11 was used in place of the polyester [A-1]. Then, the properties were evaluated by the methods mentioned above. The results are shown in Table 4.

Example 2Q A polyester composition was prepared in the same manner as in Example 13, except that the polyester [A-3] was used instead of the polyester [Al], and the weight ratio of [A-3] to [ Bl] was made from 10: 90. Then, the properties were evaluated by the methods mentioned above. The results are shown in Table 4.

Example 21 A polyester composition was prepared in the same manner as in Example 13, except that the polyester [A-3] of Example 12 was used in place of the polyester [A-4], and. the weight ratio of [A-4] to [B-l] was made from 10: 90.

Then, the properties were evaluated by the methods mentioned above. The results are shown in Table 4.

Comparative Example 6 The second polyester [B-1] was molded and injection molded to a square plate, a film and a bottle in the manner described above. Then, the opacity, the average crystallization time, the carbon dioxide gas transmission rate, the heat resistance and the appearance of the bottle were evaluated by the methods mentioned above. The results are shown in Table 4.

Comparative Example 7 A polyester composition was prepared in the same manner as in Example 13, except that a second "polyester [B-2] (polyethylene terephthalate, diethylene glycol content: 1.33 weight percent, viscosity was used. Intrinsic [IV]: 0.775 deciliters / gram) instead of the polyester [Al] and the weight index of [B-2] to [Bl] was made from 20: 80. Afterwards, the properties were evaluated by the methods mentioned above The results are shown in Table 4.

Table 4 Example 23 The polyester [Al] was melted to form the first resin layer and the polyester [Bl] (polyethylene terephthalate, diethylene glycol content: 1.95 weight percent, intrinsic viscosity [IV]: 0.835 deciliters / gram) to form the second resin layer by an extrusion molding machine at a cylinder temperature of 280 ° C, and were fed to a layer-forming die to produce a tube (total wall thickness: 6 millimeters) having a two-layer structure consisting of a [Al] layer (thickness: 0.6 millimeters) as an outer layer and a layer of [Bl] (thickness: 5.4 millimeters) as an inner layer. The temperature of the cooling water was 50 ° C. The outer diameter of the tube was 22 millimeters. The resulting tube was cut. One end of the tube that was cut in that way was melted by heating to provide a bottom and the other end was melted by heating to provide a neck. In this way, a preform was obtained that had a full length of 70 millimeters and a weight of 23 grams. The preform was heated to a temperature of 100 to 130 ° C and subjected to blow molding with biaxial stretching, first at a longitudinal stretch index of 3 times and then at a transverse stretch index of 3 times by the use of a blow molding machine with biaxial stretching at a blowing pressure of 25 kilogra-mos / square centimeter, to produce a bottle. The body of the bottle was subjected to settling by heat at 150CC for 1 minute. The bottle was evaluated in terms of mean crystallization time, carbon dioxide gas transmission rate, heat resistance and appearance through the methods mentioned above. The results are shown in Table 5.

Example 23 A bottle was produced in the same manner as in the Example 22, except that a preform was produced with the layer [A-l] having a thickness of 0.9 millimeters and layer [B-l], 5.1 millimeters thick. The bottle was evaluated by the methods mentioned above. The results are shown in Table 5.

Example 24 A bottle was produced in the same manner as in the Example 22, except that the polyester [A-2] was used instead of the polyester [A-1]. The bottle was evaluated by the methods mentioned above. The results are shown in Table 5.

Example 25 A bottle was produced in the same manner as in the Example 22, except that the polyester [A-2] was used in place of the polyester [Al] and that a preform was produced having the layer [A-2] of 0.9 millimeters thick and the layer [Bl] of 5.1 millimeters of thickness. The bottle was evaluated by the methods mentioned above. In Table 5 are shown the results.

Example 26 A bottle was produced in the same manner as in Example 22, except that the polyester [A-3] was used in place of the polyester [A-1]. The bottle was evaluated by the methods mentioned above. The results are shown in Table 5.

Example 27 A bottle was produced in the same manner as in Example 22, except that the polyester [A-3] was used instead of the polyester [Al] and that a preform having the layer [A-3] was produced. of 0.9 millimeters of thickness and the layer [Bl] of 5.1 millimeters of thickness. The bottle was evaluated by the methods mentioned above. The results are shown in Table 5.

Example 28 A bottle was produced in the same manner as in the Example 22, except that the polyester [A-4] was used instead of the polyester [A-1]. The bottle was evaluated by the methods mentioned above. The results are shown in Table 5.

Example 29 A bottle was produced in the same manner as in Example 22, except that the polyester [A-4] was used in place of the polyester [Al] and that a preform having the layer [A-3] of 0.9 millimeters thick and the layer [Bl] of 5.1 millimeters thick. The bottle was evaluated by the methods mentioned above. The results are shown in Table 5.

Comparative Example 8 A bottle was produced in the same manner as in Example 22, except that a preform was produced having only the layer [B-1] of 6 millimeters thick without the use of the polyester [A-1]. The bottle was evaluated by the methods mentioned above. The results are shown in Table 5.

Claims

1. A polyester comprising: dicarboxylic acid constituent units derived from at least one dicarboxylic acid selected from the group consisting of terephthalic acid, isophthalic acid and naphthalenedicarboxylic acid, and diol constituent units derived from diols comprising glycol of ethylene and polyalkylene glycol having an alkylene chain of 2 to 10 carbon atoms, wherein the proportion of constituent units derived from the polyalkylene glycol is in the range of 0.001 to 10 weight percent, based on the constituent units of diol.

2. The polyester, as claimed in claim 1, wherein the constituent units of dicarboxylic acid are derived from dicarboxylic acids which mainly contain terephthalic acid.

3. The polyester, as claimed in claim 1, wherein the constituent units of dicarboxylic acid contain mainly constituent units of dicarboxylic acid derived from terephthalic acid and isophthalic acid, and the proportion of constituent units derived from isophthalic acid is in the range of 1 to 15 weight percent, based on the constituent units of dicarboxylic acid.

4. The polyester, as claimed in claim 1, wherein the dicarboxylic acid constituent units contain mainly dicarboxylic acid constituent units derived from naphthalenedicarboxylic acid and isophthalic acid, and the proportion of the constituent units derived from the Naphthalenedicarboxylic acid is in the range of 100 to 55 weight percent, based on the constituent units of dicarboxylic acid. 5. The polyester as claimed in any of claims 1 to 4, wherein the polyalkylene glycol has a degree of polymerization (n) of 5 to 50. 6. The polyester as claimed in any of claims 1 to

5. , wherein the polyalkylene glycol is polytetramethylene glycol. 7. A preform formed from the polyester, as claimed in any of claims 1 to

6. 8. A biaxially stretched bottle comprising the polyester as claimed in any of claims 1 to 6. 9. The bottle biaxially stretched as shown in FIG. claimed in claim 8, wherein the body of the bottle has a carbon dioxide gas transmission rate of not more than 17.5 cc »mm / m2» day »atm. 10. The biaxially stretched bottle as claimed in claim 8, wherein the body of the bottle has a carbon dioxide gas transmission rate of not more than 15.0 cc * mm / m2 # day »atm. The biaxially stretched bottle as claimed in claim 8, wherein the body of the bottle has a carbon dioxide gas transmission rate of not more than 4.0 cc »mm / d» day »atm. 12. A polyester composition comprising: [A] a polyester as defined in any of claims 1 to 6, as a first polyester, in an amount of 1 to 99 percent by weight, and [B] a second polyester in an amount of 1 to 99 weight percent, the second polyester comprising constituent units of dicarboxylic acid derived from at least one dicarboxylic acid selected from the group consisting of terephthalic acid, isophthalic acid and naphthalenedicarboxylic acid, and constituent units of diol derived from diols comprising ethylene glycol, wherein the proportion of constituent units derived from a polyalkylene glycol is less than 0.001 percent by weight, based on to the constituent units of diol. 13. A laminate having a multilayer structure comprising: [I] a first resin layer formed from a polyester, as defined in any of claims 1 to 6, or a polyester composition, as defined in claim 12, and [II] a second resin layer formed from at least one resin selected from the group consisting of (a) a second polyester [B], (b) a polyamide and (c) a polyolefin, the second polyester comprising [B] constituent units of dicarboxylic acid derived from at least one dicarboxylic acid selected from the group consisting of terephthalic acid, isophthalic acid and naphthalenedicarboxylic acid , and diol constituent units derived from diols comprising ethylene glycol, wherein the proportion of constituent units derived from a polyalkylene glycol is less than 0.001 weight percent, based on the constituent units of diol. 14. The polyester laminate, as claimed in claim 13, in the form of a preform. 15. The polyester laminate, as claimed in claim 13, in the form of a bottle. 16. The polyester laminate, as claimed in claim 15, wherein the body of the bottle has a carbon dioxide gas transmission rate of not more than 17.5 cc «mm / pr * day» atm. 1

7. The polyester laminate, as claimed in claim 15, wherein the body of the bottle has a carbon dioxide gas transmission rate of not more than 15.0 cc * mm / m2 # day »atm. 1

8. The polyester laminate, as claimed in claim 15, wherein the body of the bottle has a carbon dioxide gas transmission rate of not more than 4.0 cc »mm / m2» day «atm. 1

9. A process for producing a biaxially stretched polyester bottle, comprising the steps of producing a preform from a polyester, as defined in any of claims 1 to 6, a polyester composition, as defined in claim 12, or a polyester laminate, as defined in claim 13, heat the preform, subject the preform to blow molding with biaxial stretching, to give a stretched bottle and retain the drawn bottle in a mold, at a temperature of not less than 100 ° C. 20. The process for producing a biaxially stretched polyester bottle, as claimed in claim 19, wherein the neck of the preform is crystallized by heat prior to blow molding with Biaxial stretching. 21. The process for producing a biaxially stretched polyester bottle, as claimed in claim 19, wherein the neck of the bottle is crystallized by heat after blow molding with biaxial stretching. 22. The process for producing a biaxially stretched polyester bottle, as claimed in any of claims 19 to 21, wherein the body of the resulting bottle has a carbon dioxide gas transmission rate of not more than 17.5 cc. «Mm / m2 * day * atm. 23. The process for producing a biaxially stretched polyester bottle, as claimed in any of claims 19 to 21, wherein the body of the resulting bottle has a carbon dioxide gas transmission rate of not more than 15.0 cc »mm / m2» day »atm. 24. The process for producing a biaxially stretched polyester bottle, as claimed in any of claims 19 to 21, wherein the body of the resulting bottle has a carbon dioxide gas transmission rate of not more than 4.0 cc. »Mm / m2» day * atm. SUMMARY The novel polyester (first polyester [A]) of the invention comprises dicarboxylic acid constituent units derived from at least one dicarboxylic acid selected from the group consisting of terephthalic acid, isophthalic acid and naphthalenedicarboxylic acid, and diol constituent units derivatives from diols comprising ethylene glycol and a polyalkylene glycol having an alkylene chain of 2 to 10 carbon atoms, wherein the proportion of constituent units derived from the polyalkylene glycol is from 0.001 to 10 percent by weight, based on the diol constituent units. The polyester [A] has an excellent crystallization index, is suitably used individually or as compositions together with another polyester [B] and / or other polymers, for the production of molded products such as films, sheets, laminates, preforms and bottles, which have excellent gas barrier, transparency and heat resistance properties. The polyester composition of the invention comprises from 1 to 99 weight percent of the first polyester [A] and from 1 to 99 weight percent of the second polyester [B], a polyamide and / or a polyolefin. The polyester laminate of the invention has a multilayer structure comprising a first resin layer of the first polyester [A] or composition, and a second resin layer of another polyester [B], a polyamide and / or a polyolefin. The process for producing a biaxially stretched bottle comprises the steps of producing a preform from the first polyester [A], the composition or the polyester laminate, heating it, subjecting it to blow molding with biaxial stretching, to give a stretched bottle and retain the bottle in a mold, at a temperature of not less than 100 ° C.