JP4684589B2 - Resin composition and method for producing the same - Google Patents

Description

  The present invention relates to an ethylene-vinyl alcohol copolymer resin composition, and particularly to an ethylene-vinyl alcohol copolymer resin composition having a saponification degree of 80 to 99 mol%. Moreover, it is related with the resin composition which consists of the said resin composition and another thermoplastic resin. Furthermore, it is related with the manufacturing method of those resin compositions, and its use.

  An ethylene-vinyl alcohol copolymer (hereinafter sometimes abbreviated as EVOH) is a useful polymer material excellent in oxygen shielding properties, oil resistance, non-charging properties, mechanical strength, etc. Widely used as packaging material. There are various methods for forming EVOH pellets into various molded products, but they are often melt-molded like extrusion molding or injection molding. However, since the melting temperature must normally be 200 ° C. or higher when molding EVOH resin, EVOH that does not contain additives tends to deteriorate during melt molding, causing fish eyes and blisters to the product and reducing the quality. There was sometimes. In addition, it is necessary to add an additive in order to improve the interlaminar adhesion at the time of use with another resin.

  WO99 / 05213 pamphlet (US Pat. No. 6,174,949) includes at least one selected from a boron compound as an essential component, acetic acid as an optional component, and an acetate and a phosphate compound as an essential component. The content of each component with respect to 100 parts by weight of EVOH, the boron compound is 0.001 to 1 part by weight in terms of boron, the acetic acid is 0 to 0.05 parts by weight, and the acetate is 0 in terms of metal. An EVOH resin composition in which 0.001 to 0.05 parts by weight and the phosphoric acid compound is 0.0005 to 0.05 parts by weight in terms of phosphate group is described. This resin composition is said to be an EVOH resin composition with improved long run properties, appearance, and interlayer adhesion. Here, it is described that the purpose of blending acetate is to improve long run properties and interlayer adhesion.

  Japanese Patent Application Laid-Open No. 2001-164059 (European Patent Application Publication No. 1090953) is an EVOH resin composition characterized in that the MFR exhibits a specific behavior when the resin composition is heated and melted. Carboxylic acid having a molecular weight of less than 75 is 50 to 500 ppm, alkali metal salt is 50 to 500 ppm in terms of metal element, alkaline earth metal salt is 10 to 120 ppm in terms of metal element, phosphate compound is 10 to 200 ppm in terms of phosphate radical, A resin composition containing 50 to 2000 ppm of a boron compound in terms of boron element is described. This resin composition is said to be an EVOH resin composition that is excellent in appearance and long run property during melt molding, little colored during recovery, and excellent in interlayer adhesion when formed into a laminate. Here, an alkali metal salt is added to improve interlayer adhesion, and a boron compound is added to improve long-run properties.

  As a method for producing EVOH pellets containing the additive, a method in which EVOH hydrous pellets are brought into contact with an aqueous solution containing the additive is described as a representative method. According to this method, it is easy to control the amount of trace components contained in the EVOH pellets by adjusting the solution concentration, and it is possible to obtain stable quality pellets by drying after contacting with the aqueous solution.

  As described above, in order to improve interlayer adhesion, an alkali metal salt is added to the EVOH resin, and is typically added as an acetate salt. In many cases, acetic acid not forming a salt is also added at the same time. However, the EVOH resin composition containing an acetate group in this way sometimes gives off an acetic acid odor. One of the main uses of the EVOH resin composition is a food packaging container, and there has been a demand for an EVOH resin composition with less odor generation in the market. Further, an EVOH resin composition having improved melt stability and excellent long run properties is desired.

  On the other hand, when EVOH hydrous pellets are brought into contact with an aqueous solution containing acetic acid or acetate to produce EVOH resin composition pellets, acetic acid is released into the atmosphere when the hydrous pellets after contact are dried. In many cases, the surrounding environment and work environment may be adversely affected.

  EVOH having a low saponification degree is superior in flexibility as compared with a normal EVOH having a high saponification degree, and is used in applications where flexibility is more important than gas barrier properties. In particular, a resin composition in which EVOH having a low saponification degree is blended with EVOH having a high saponification degree is widely used in thermoformed containers and the like as a resin composition having good transparency and secondary processability. . In the case of producing a resin composition composed of EVOH having such a low saponification degree, an additive has been conventionally contained by the method as described above. For this reason, the conventional manufacturing method as described above still has the problems.

International Publication No. 99/05213 Pamphlet JP 2001-164059 A

  The present invention has been made to solve the above problems, and provides an EVOH resin composition excellent in flexibility, secondary processability and interlayer adhesion, or a resin composition comprising it and other thermoplastic resins. It is intended to do. Another object of the present invention is to provide a method for producing an environmentally friendly resin composition that does not discharge carboxylic acid such as acetic acid to the surrounding environment.

The said subject is content of an alkali metal salt (A) 0.1-20 micromol / g in conversion of an alkali metal, and content of carboxylic acid or its salt (C) is 2 micromol / g or less in conversion of carboxylic acid root. , ethylene - vinyl ethylene content of alcohol copolymer resin is 5 to 60 mol%, ethylene - vinyl a saponification degree of alcohol copolymer resin Ri 80 to 99 mol% der, and the alkali metal salt ( The problem is solved by providing an ethylene-vinyl alcohol copolymer resin composition (F) in which at least a part of A) is a carbonate or bicarbonate . At this time, the ethylene content is preferably 47 to 60 mol%. It is also preferred that the alkali metal salt (A) is a potassium salt. Moreover, it is also suitable that content of alkaline-earth metal salt (E) is 0.25 micromol / g or less in conversion of alkaline-earth metal. A preferred embodiment is a molded article comprising the ethylene-vinyl alcohol copolymer resin composition (F), particularly a film, a blow molded container, or a thermoformed container. A multilayer structure including at least one layer composed of the ethylene-vinyl alcohol copolymer resin composition (F) is also a preferred embodiment.

The said subject is content of an alkali metal salt (A) 0.1-20 micromol / g in conversion of an alkali metal, and content of carboxylic acid or its salt (C) is 2 micromol / g or less in conversion of carboxylic acid root. , ethylene - vinyl ethylene content of alcohol copolymer resin is 5 to 60 mol%, ethylene - vinyl a saponification degree of alcohol copolymer resin Ri 80 to 99 mol% der, and the alkali metal salt ( A- 99% by weight of ethylene-vinyl alcohol copolymer resin composition (F ) in which at least a part of A) is carbonate or bicarbonate , ethylene content is 5 to 60 mol%, saponification degree This can be solved by providing a resin composition comprising 1 to 99% by weight of an ethylene-vinyl alcohol copolymer resin having a ratio of 99.2 to 100 mol% . A preferred embodiment is a molded article made of the resin composition, particularly a film, a blow molded container, or a thermoformed container. A multilayer structure including at least one layer made of the resin composition is also a preferred embodiment.

The above problem is that an ethylene-vinyl alcohol copolymer having an ethylene content of 5 to 60 mol% and a saponification degree of 80 to 99 mol% is added to an aqueous solution containing an alkali metal carbonate or hydrogen carbonate and carbon dioxide. It can also be solved by providing a method for producing an ethylene-vinyl alcohol copolymer resin composition (F) in which a polymer resin is brought into contact. At this time, the ethylene content is preferably 47 to 60 mol%. A preferred embodiment is a method for producing a molded product obtained by melt molding the ethylene-vinyl alcohol copolymer resin composition (F), particularly a method for producing a film, a blow molded container, or a thermoformed container. Moreover, the manufacturing method of the multilayered structure which laminates | stacks the said ethylene-vinyl alcohol copolymer resin composition (F) and a thermoplastic resin is also a suitable embodiment.

Moreover, the said subject is ethylene-vinyl alcohol whose ethylene content is 5-60 mol% and saponification degree is 80-99 mol% in the aqueous solution containing carbonate or hydrogencarbonate of an alkali metal , and a carbon dioxide gas. After contacting the copolymer resin , melt-kneading with an ethylene-vinyl alcohol copolymer resin having an ethylene content of 5 to 60 mol% and a saponification degree of 99.2 to 100 mol% It is also solved by providing a method for producing a resin composition . A preferred embodiment is a method for producing a molded product obtained by melt-molding the resin composition, particularly a method for producing a film, a blow molded container, or a thermoformed container. Moreover, the manufacturing method of the multilayered structure which laminates | stacks the said resin composition and a thermoplastic resin is also a suitable embodiment.

  The resin composition of the present invention is excellent in barrier properties and excellent in flexibility, secondary workability and interlayer adhesion. Moreover, the manufacturing method of the resin composition of this invention considers the environment without discharging | emitting carboxylic acid, such as an acetic acid, to the surrounding environment.

  First, the manufacturing method of EVOH resin composition (F) of this invention is demonstrated. A suitable manufacturing method is a manufacturing method which makes ethylene-vinyl alcohol copolymer resin contact the aqueous solution containing an alkali metal salt (A) and a carbon dioxide gas.

  Conventionally, in order to contain an additive such as an alkali metal salt (A) in an EVOH resin, a method of bringing EVOH into contact with an aqueous solution containing these additives has been performed. The EVOH resin composition (F) of the present invention is characterized in that it is brought into contact with an aqueous solution containing carbon dioxide gas in addition to the above additives.

  In order to improve interlayer adhesion in a multilayer structure including an EVOH resin composition (F) layer, it is desirable that the EVOH resin composition (F) contains an alkali metal salt (A). A) In particular, the EVOH resin was often immersed in an aqueous solution containing an alkali metal acetate. At this time, if the liquid to be immersed is kept alkaline, the stability at the time of melt molding is often lowered, and in order to solve this problem, an acid, particularly a carboxylic acid typified by acetic acid, is often contained separately.

  However, when the content of carboxylic acid radicals derived from carboxylic acids and carboxylates is high, the EVOH resin composition often generates a carboxylic acid odor, which may be a problem when used for food packaging applications. was there. In addition, there has been a problem that carboxylic acid is released to the surrounding environment when it is dried after being brought into contact with an aqueous solution containing an additive. Accordingly, there has been a demand for a method that does not make the aqueous solution containing the additive alkaline, while containing the alkali metal salt (A) and minimizing the content of carboxylic acid radicals. The EVOH resin composition (F) of the present invention can solve this problem by containing carbon dioxide gas in an aqueous solution containing an alkali metal salt (A) instead of using acetic acid.

  The EVOH used in the EVOH resin composition (F) of the present invention is preferably one obtained by saponifying an ethylene-vinyl ester copolymer, and in particular, one obtained by saponifying an ethylene-vinyl acetate copolymer. Is particularly preferred. The ethylene content is 5 to 60 mol%, whereby a molded product excellent in gas barrier properties and melt moldability can be obtained. When the ethylene content is less than 5 mol%, the flexibility becomes insufficient and the melt moldability deteriorates. When the ethylene content exceeds 60 mol%, the gas barrier property becomes insufficient. The lower limit of the ethylene content is preferably 20 mol% or more, and more preferably 40 mol% or more. Furthermore, for example, when used for applications requiring a high degree of secondary workability such as deep-drawn containers, it is particularly preferable that the ethylene content of EVOH is 47 to 60 mol%. When the ethylene content is less than 47 mol%, the flexibility becomes insufficient and the deep drawability may be deteriorated. On the other hand, the upper limit of the ethylene content is preferably 55 mol% or less.

  Moreover, the saponification degree of the vinyl acetate component in EVOH used by the EVOH resin composition (F) of this invention is 80-99 mol%. In order to obtain a resin composition having good gas barrier properties and excellent secondary processability such as thermoformability, the saponification degree of EVOH is preferably 80 to 99 mol%. When the degree of saponification is less than 80 mol%, the gas barrier property becomes poor and the thermal stability during melt molding tends to be extremely lowered. When the degree of saponification exceeds 99.0 mol%, the flexibility tends to decrease, and cracks, pinholes, localized in the EVOH layer particularly in applications that require a high degree of secondary workability such as deep drawing containers. It tends to cause uneven thickness. The saponification degree is more preferably 90 mol% or more, and still more preferably 95 mol% or more. On the other hand, the saponification degree is more preferably 98 mol% or less.

  Further, when ethylene and vinyl acetate are copolymerized, other fatty acid vinyl esters (vinyl propionate, vinyl pivalate, etc.) can be used in combination. Moreover, EVOH can contain 0.0002-0.2 mol% of vinyl silane compounds as a copolymerization component. Here, examples of the vinylsilane compound include vinyltrimethoxysilane, vinyltriethoxysilane, vinyltri (β-methoxy-ethoxy) silane, and γ-methacryloxypropylmethoxysilane. Of these, vinyltrimethoxysilane and vinyltriethoxysilane are preferably used.

  The EVOH production method will be specifically described below. The polymerization of ethylene and vinyl acetate is not limited to solution polymerization, and may be any of solution polymerization, suspension polymerization, emulsion polymerization, bulk polymerization, and may be either continuous or batch-type. The polymerization conditions in the case of polymerization are as follows.

Solvent: Alcohols are preferred, but other organic solvents (such as dimethyl sulfoxide) that can dissolve ethylene, vinyl acetate, and ethylene-vinyl acetate copolymer can be used. As alcohols, methyl alcohol, ethyl alcohol, propyl alcohol, n-butyl alcohol, t-butyl alcohol and the like can be used, and methyl alcohol is particularly preferable.
Catalyst: 2,2-azobisisobutyronitrile, 2,2-azobis- (2,4-dimethylvaleronitrile), 2,2-azobis- (4-methyl-2,4-dimethylvaleronitrile), 2 , 2-azobis- (4-methoxy-2,4-dimethylvaleronitrile), 2,2-azobis- (2-cyclopropylpropionitrile) and the like azonitrile initiators, isobutyryl peroxide, cumylperoxyneo Organic peroxides such as decanoate, diisopropyl peroxycarbonate, di-n-propyl peroxydicarbonate, t-butyl peroxyneodecanoate, lauroyl peroxide, benzoyl peroxide, t-butyl hydroperoxide An initiator or the like can be used.
Temperature; 20-90 ° C, preferably 40 ° C-70 ° C.
Time (average residence time in case of continuous type); 2 to 15 hours, preferably 3 to 11 hours.
Polymerization rate: 10 to 90%, preferably 30 to 80%, relative to the charged vinyl ester.
Resin content in the solution after polymerization; 5 to 85%, preferably 20 to 70%.
Ethylene content in the copolymer; preferably 5 to 60 mol%, more preferably 20 to 60 mol%, optimally 47 to 60 mol%.

  In addition to ethylene and vinyl acetate, monomers that can be copolymerized with these, for example, α-olefins such as propylene, isobutylene, α-octene, α-dodecene; acrylic acid, methacrylic acid, crotonic acid, maleic acid, itacone Unsaturated acids such as acids or their anhydrides, salts, mono- or dialkyl esters, etc .; Nitriles such as acrylonitrile and methacrylonitrile; Amides such as acrylamide and methacrylamide; Ethylene sulfonic acid, allyl sulfonic acid, methallyl sulfone An olefin sulfonic acid such as an acid or a salt thereof; alkyl vinyl ethers, vinyl ketone, N-vinyl pyrrolidone, vinyl chloride, vinylidene chloride and the like can also be present in a small amount.

  After polymerization for a predetermined time, after reaching a predetermined polymerization rate, a polymerization inhibitor is added if necessary, and unreacted ethylene gas is removed by evaporation, and then unreacted vinyl acetate is driven off. As a method of driving off unreacted vinyl acetate from the ethylene-vinyl acetate copolymer solution from which ethylene has been removed by evaporation, for example, the copolymer solution is continuously supplied at a constant rate from the upper part of a tower packed with Raschig rings, A method in which an organic solvent vapor such as methanol is blown from the bottom of the tower, a mixed vapor of an organic solvent such as methanol and unreacted vinyl acetate is distilled from the top of the tower, and the copolymer solution from which the unreacted vinyl acetate has been removed is removed from the bottom of the tower Etc. are adopted.

An alkali catalyst is added to the copolymer solution from which unreacted vinyl acetate has been removed to saponify the vinyl acetate component in the copolymer. The saponification method can be either continuous or batch. As the alkali catalyst, sodium hydroxide, potassium hydroxide, alkali metal alcoholate or the like is used. Moreover, as a solvent used for saponification, methanol is preferable. The saponification conditions are, for example, as follows, but the saponification degree can be adjusted by adjusting the water content of the saponification reaction solution. In order to obtain EVOH having a saponification degree of 80 to 99 mol%, a water content of 1000 to 20000 ppm is preferred.
The copolymer solution concentration: 10 to 50%.
Reaction temperature: 30-150 ° C.
Amount of catalyst used: 0.005 to 0.6 equivalent (per vinyl acetate component).
Time (in the case of continuous type, average residence time); 10 minutes to 6 hours.

In general, in the case of saponification by a continuous method, methyl acetate produced by saponification can be removed more efficiently, so that a smaller amount of catalyst may be used than in the case of a batch method. In the case of a continuous type, it is necessary to saponify at a higher temperature in order to prevent precipitation of EVOH produced by saponification. Therefore, it is preferable to set the reaction temperature and the catalyst amount within the following ranges in the continuous method. In this case as well, the degree of saponification can be adjusted by adjusting the water content of the saponification reaction solution. In order to obtain EVOH having a saponification degree of 80 to 99 mol%, a water content of 1000 to 20000 ppm is preferred.
Reaction temperature: 70-150 ° C.
Amount of catalyst used: 0.005 to 0.1 equivalent (per vinyl acetate component).

  The saponification degree after the saponification reaction is 80 to 99 mol%. This degree of saponification can be arbitrarily adjusted according to conditions.

  The method for producing EVOH pellets from the obtained alcohol solution of EVOH after saponification is not particularly limited. Preferably, an alcohol solution of EVOH is precipitated in a strand form in a coagulation bath, and then the strands are cut to obtain water-containing pellets. In the precipitation, the alcohol solution may be concentrated to increase the EVOH concentration as compared with the saponification, or a part or all of methanol may be replaced with water, and the EVOH water / alcohol mixed solution or A water-containing composition of EVOH may be used. A water-containing pellet is obtained by extruding this into water or an alcohol aqueous solution containing a small amount of alcohol, and precipitating it into a strand shape, followed by cutting. Moreover, it can cut | disconnect with a fluid state, without making it precipitate in a strand form, and can also solidify in water and can manufacture a pellet.

  The water-containing pellets obtained as described above are porous, and the saponification catalyst residue can be easily removed by washing with water, and the subsequent addition of additives and drying operations are also easy. It is preferable that the moisture content of such a water-containing pellet is 10 to 80% by weight because of the above operational advantages. The water content is more preferably 20% by weight or more, and further preferably 30% by weight or more. Moreover, it is 70 weight% or less more suitably.

  The water-containing pellets thus obtained usually contain an alkali metal salt that is a saponification catalyst residue, for example, sodium acetate, which causes problems such as coloring, and thus is preferably removed by washing. Usually, the alkali metal salt content of the water-containing pellets before washing is about 100 to 10,000 μmol / g (per EVOH weight) in terms of alkali metal. The cleaning method is not particularly limited, but a method of cleaning with water is preferable. The water used as the cleaning liquid at this time may be an aqueous solution of an acid such as acetic acid in order to efficiently remove alkali metal ions. Moreover, it is also preferable to reduce the content of the saponification catalyst residue efficiently by using water washing and acid washing together.

  It is preferable to reduce the alkali metal content of the water-containing pellets after washing to 0-50 μmol / g (per EVOH weight) in terms of alkali metal. The upper limit of the alkali metal content is more preferably 40 μmol / g, still more preferably 30 μmol / g, and particularly preferably 20 μmol / g. Since the saponification catalyst residue is usually contained in the form of an alkali metal salt of acetic acid, the content of carboxylic acid radicals was reduced by sufficiently reducing the alkali metal content of the water-containing pellets after washing. It becomes easy to obtain an EVOH composition.

  The method for washing the water-containing pellets is not particularly limited, and either a batch type processing container or a continuous type processing container can be used. Especially, the method of supplying and processing a pellet continuously in a tower type container is suitable from a viewpoint of productivity.

  In the EVOH resin composition (F) of this invention, the manufacturing method of EVOH resin composition (F) which makes EVOH resin contact the aqueous solution containing an alkali metal salt (A) and a carbon dioxide gas is used suitably. That is, the aqueous solution with which the EVOH resin is brought into contact is an aqueous solution containing an alkali metal salt (A) and carbon dioxide gas.

  The amount of carbon dioxide gas contained in the aqueous solution is not particularly limited and can be appropriately adjusted. However, the amount of carbon dioxide gas present in the air is more than the amount that naturally dissolves carbon dioxide gas. It is necessary to let The concentration of carbon dioxide gas in the aqueous solution (total of free carbon dioxide and carbonic acid) is preferably 0.5 mmol / L or more, more preferably 2 mmol / L or more, and further preferably 10 mmol / L or more. . Moreover, in order to raise the solubility of a carbon dioxide gas, you may process on pressurization conditions of about 1.5-10 atmospheres.

  When a continuous processing vessel, particularly a tower type vessel, is used to continuously feed and process pellets, when the concentration of carbon dioxide in the aqueous solution is too high, bubbles are generated around the EVOH pellets. In some cases, the resin sedimentation may be adversely affected. Therefore, when such a continuous processing process is applied, it may be preferable that the carbon dioxide concentration in the aqueous solution is lower than the saturated carbon dioxide concentration. In this case, the carbon dioxide concentration is set to a value less than the saturated carbon dioxide concentration, preferably 0.95 times or less of the saturated carbon dioxide concentration, more preferably 0.9 times or less the saturated carbon dioxide concentration. The This concentration is determined by affecting the temperature and pressure of the treatment liquid. On the other hand, when a batch-type processing container is used, the above problem of sedimentation usually does not occur, but the upper limit value of the carbon dioxide gas concentration can be set in the same manner as in the continuous processing container.

  The aqueous solution preferably contains an alkali metal salt (A) from the viewpoint of securing interlayer adhesion and long run properties. The preferred range of the content of the alkali metal salt (A) is affected by the water content of the water-containing pellets, but generally it is preferably 0.05 to 40 mmol / L. A more preferable lower limit of the content of the alkali metal salt (A) in the aqueous solution is 0.1 mmol / L. A more preferred upper limit is 20 mmol / L. As will be described later, the preferred content of the alkali metal salt (A) in the EVOH resin composition (F) varies depending on the ethylene content of EVOH, and accordingly, the alkali metal salt ( It is preferable to adjust the content of A).

  The cation species of the alkali metal salt (A) is not particularly limited. It is selected from lithium, sodium, potassium, rubidium and cesium salts, with sodium and potassium salts being preferred, and potassium being particularly preferred. By using a potassium salt, a resin composition excellent in both interlayer adhesion and long run properties can be obtained.

  The anion species of the alkali metal salt (A) is not particularly limited. Can be added as carbonate, bicarbonate, phosphate, hydrogen phosphate, hydroxide, carboxylate, etc. Among them, added as carbonate, bicarbonate, hydrogen phosphate and hydroxide It is preferable to do. Moreover, it is also preferable to add as a borate as shown below. However, in view of the purpose of the present invention to reduce the content of carboxylic acid radicals, it is better not to be a carboxylate.

  Further, the aqueous solution may contain a boron compound (B) in order to suppress adhesion of eyes or eyes near the die during melt molding. When the concentration of the boron compound (B) in the aqueous solution is 0.1 to 50 mmol / L in terms of boron element, an appropriate amount of the boron compound (B) can be contained in the dry resin composition pellets. It is preferable. The lower limit value of the concentration of the boron compound (B) is more preferably 0.5 mmol / L or more, and further preferably 1 mmol / L or more. The upper limit is more preferably 40 mmol / L or less, and even more preferably 30 mmol / L or less. When it exceeds 50 mmol / L, the EVOH resin composition (F) is easily gelled, and the appearance of the molded product may be deteriorated.

  Examples of the boron compound (B) used for the preparation of the aqueous solution include, but are not limited to, boric acids, boric acid esters, borates, borohydrides, and the like. Specific examples of boric acids include orthoboric acid, metaboric acid, and tetraboric acid. Examples of boric acid esters include triethyl borate and trimethyl borate. Examples include alkali metal salts of acids, alkaline earth metal salts, and borax. Among these compounds, orthoboric acid (hereinafter sometimes simply referred to as boric acid) is preferable.

  Moreover, it is desirable for the said aqueous solution not to contain carboxylic acid or its salt (C) from the meaning of this invention. However, this does not exclude that the carboxylic acid or its salt (C) remaining in the EVOH resin dissolves into the aqueous solution and is contained as a result. Moreover, it does not exclude containing carboxylic acid or its salt (C) in the range which does not inhibit the effect of this invention.

  In order to balance the long run property and the color resistance at the time of melt molding, particularly the color resistance at the time of high temperature molding and the interlayer adhesion, the aqueous solution preferably contains a phosphoric acid compound (D). By containing an appropriate amount of the phosphoric acid compound (D), it is possible to suppress coloring of the molded product and generation of gels and blisters when the obtained EVOH resin composition (F) is melt-molded. The upper limit of the concentration of the phosphoric acid compound (D) in the aqueous solution when adding the phosphoric acid compound (D) is preferably 10 mmol / L, more preferably 5 mmol / L in terms of phosphate radical. More preferably, it is 3.5 mmol / L, and most preferably 2.5 mmol / L. On the other hand, the lower limit value of the concentration of the phosphoric acid compound (D) in the aqueous solution when adding the phosphoric acid compound (D) is preferably 0.01 mmol / L, more preferably 0 in terms of phosphate radical. 0.03 mmol / L, more preferably 0.05 mmol / L, and most preferably 0.1 mmol / L.

  As the phosphoric acid compound (D) used for the preparation of the aqueous solution, an inorganic phosphoric acid compound is preferably used, and various acids such as phosphoric acid and phosphorous acid and salts thereof are exemplified. The phosphate may be contained in any form of primary phosphate, secondary phosphate, and tertiary phosphate, and its cationic species is not particularly limited, but alkali metal salts It is preferable that Among these, it is preferable to add the phosphoric acid compound (D) in the form of sodium dihydrogen phosphate, potassium dihydrogen phosphate, disodium hydrogen phosphate, or dipotassium hydrogen phosphate.

  The aqueous solution may contain an alkaline earth metal salt (E). However, since the alkaline earth metal salt tends to form a hardly soluble carbonate, it is not appropriate to add it in a large amount. Moreover, when there is much content of alkaline-earth metal salt (E), there exists a possibility that EVOH resin composition (F) may color at the time of melt molding. The addition of the alkaline earth metal salt (E) is optional, and it is preferable that the alkaline earth metal salt (E) is not added positively. However, when added, the concentration of the alkaline earth metal salt (E) in the aqueous solution is 0 in terms of alkaline earth metal. It is the range of -0.2 mmol / L, More preferably, it is 0.1 mmol / L or less, More preferably, it is 0.05 mmol / L or less.

  The cationic species of the alkaline earth metal salt (E) is not particularly limited. Magnesium salts, calcium salts, barium salts, strontium salts and the like can be mentioned, and magnesium salts and calcium salts are preferred. The anionic species of the alkaline earth metal salt (E) is not particularly limited. Can be added as carbonate, bicarbonate, phosphate, hydrogen phosphate, hydroxide, carboxylate, etc. Among them, added as carbonate, bicarbonate, hydrogen phosphate and hydroxide It is preferable to do. Usually, the above alkaline earth metal salts are hardly soluble in water, but the solubility increases due to the presence of carbonic acid. However, in view of the purpose of the present invention to reduce the content of carboxylic acid radicals, it is better not to be a carboxylate.

  The pH of the aqueous solution containing the additive and carbon dioxide gas is preferably 3.5 to 6.5. By containing a certain amount or more of carbon dioxide gas, such an acidic aqueous solution can be obtained. The pH value is more preferably 3.8 or more, and further preferably 4 or more. Further, the pH value is more preferably 6.3 or less, further preferably 6.0 or less, and most preferably 5.8 or less.

  The method for preparing the aqueous solution containing the additive and carbon dioxide gas is not particularly limited. An additive such as an alkali metal salt (A) may be added to an aqueous solution in which carbon dioxide gas is previously dissolved. Conversely, carbon dioxide gas may be dissolved in an aqueous solution in which an additive such as an alkali metal salt (A) is previously dissolved. Alternatively, each aqueous solution may be prepared in advance and then mixed.

  A method of bringing the EVOH resin into contact with the aqueous solution is not particularly limited, but a method of immersing the EVOH resin in the aqueous solution is desirable. The shape of the EVOH resin when immersing the EVOH resin in the aqueous solution may be any shape such as powder, granular, spherical, cylindrical pellet, etc. For example, the water-containing EVOH pellet obtained as described above may be used. It is preferable to contact the aqueous solution. By immersing the pellet in a water-containing state in an aqueous solution, an additive such as an alkali metal salt (A) can be efficiently and uniformly contained in the EVOH resin pellet. The water content of the water-containing pellets before being immersed in the aqueous solution is preferably 10 to 80% by weight. The water content is more preferably 20% by weight or more, and further preferably 30% by weight or more. Moreover, it is 75 weight% or less more suitably, More preferably, it is 70 weight% or less.

  The temperature of the aqueous solution brought into contact with the EVOH resin is not particularly limited, but is preferably 10 to 90 ° C. If it is less than 10 degreeC, there exists a possibility that it may take time to make additives, such as an alkali metal salt (A), uniformly in EVOH resin pellet, and if it exceeds 90 degreeC, the saturation solubility of a carbon dioxide gas will fall, and it is enough It may be difficult to contain a sufficient amount of carbon dioxide gas in the solution, and the pellets may be fused. The temperature of the aqueous solution is more preferably 20 ° C. or higher, and further preferably 30 ° C. or higher. Moreover, it is 85 degreeC or less more suitably, More preferably, it is 80 degreeC or less. In the case of contact at a high temperature of 70 ° C. or higher, the solubility of carbonic acid is reduced.

  The preferred range of time for contacting the EVOH resin with the aqueous solution varies depending on the form of the EVOH resin, but in the case of pellets of about 1 to 10 mm, it is preferably 1 hour or more, more preferably 2 hours or more. preferable.

  A method for bringing the EVOH resin into contact with the aqueous solution is not particularly limited. The EVOH resin can be brought into contact with water in advance, and the carbon dioxide gas and the additive can be dissolved in water later. However, the method in which the aqueous solution prepared by dissolving these in advance is brought into contact with the EVOH resin is used as an additive. A stable quality EVOH resin composition (F) containing uniformly is obtained, which is preferable.

  As a method of bringing the EVOH resin into contact with the aqueous solution, either a batch method or a continuous method can be adopted. In the continuous method, for example, a method in which the EVOH resin is brought into contact with the continuously supplied aqueous solution while gradually moving the EVOH resin downward in a tower-shaped container is preferable.

  Also, a plurality of aqueous solutions may be prepared and contacted in a plurality of times. For example, first contact with an aqueous solution containing only an additive such as an alkali metal salt (A), and then contact with an aqueous solution containing carbon dioxide in addition to the additive such as an alkali metal salt (A). It is also possible to adopt a method such as

  Furthermore, the EVOH resin is immersed in an aqueous solution containing carbon dioxide gas in addition to an additive such as an alkali metal salt (A) and brought into contact therewith, and then charged into the extruder. In the extruder, the alkali metal salt (A ), A boron compound (B), a phosphoric acid compound (D), or an aqueous solution containing an alkaline earth metal salt (E), and a method of melt kneading may be employed.

  The EVOH resin, preferably the EVOH resin pellet, is brought into contact with the aqueous solution, and then drained as necessary before being subjected to a drying step. The drying method is not particularly limited, and a hot air dryer or the like can be used, and drying may be performed while melt-kneading in an extruder with a vent. The dryer may be a fluid dryer or a stationary dryer, and may be used in combination. Among these, a method of drying by a fluidized drying method first and then drying by a stationary drying method is preferable. The drying temperature is not particularly limited, but usually a temperature of about 70 to 120 ° C. is adopted, and the temperature can be raised as the drying proceeds. The water content after drying is usually 1% by weight or less, preferably 0.5% by weight or less. Thus, dry pellets made of the EVOH resin composition (F) are obtained.

  In the method for producing the EVOH resin composition (F) described above, a resin composition containing almost no carboxylic acid radical is obtained. Therefore, in this drying step, the carboxylic acid is not volatilized and the carboxylic acid is released to the periphery. It is possible to provide a manufacturing method that takes into consideration the surrounding environment without having to do so.

  In the EVOH resin composition (F) suitably used in the present invention, the content of the alkali metal salt (A) is 0.1 to 20 μmol / g in terms of alkali metal, and the carboxylic acid or its salt (C) is used. The EVOH resin composition (F) has a content of 2 μmol / g or less in terms of carboxylate group, an ethylene content of 5 to 60 mol%, and a saponification degree of 80 to 99 mol%.

  The EVOH resin composition (F) is an EVOH resin composition (F) that hardly generates odor and is excellent in long run property, flexibility, and interlayer adhesion at the time of melt molding. The EVOH resin composition (F) is preferably manufactured by the above-described manufacturing method, but is not limited to that manufactured by the method.

  The EVOH resin composition (F) contains the alkali metal salt (A) in an amount of 0.1 to 20 μmol / g in terms of alkali metal. By containing the alkali metal salt (A), the interlayer adhesion, the coloration resistance at the time of melting, and the long run property of the EVOH resin composition (F) are improved. When the content is less than 0.1 μmol / g, the interlayer adhesion, the coloration resistance at melting and the long run property are insufficient, and when it exceeds 20 μmol / g, the coloration resistance at melting becomes poor. The lower limit of the content of the alkali metal salt (A) is more preferably 0.3 μmol / g or more, and more preferably 0.5 μmol / g or more. The upper limit of the content of the alkali metal salt (A) is preferably 15 μmol / g or less, more preferably 10 μmol / g or less, and particularly preferably 8 μmol / g or less.

At this time, it is preferable that the content of the alkali metal salt (A) and the ethylene content of EVOH satisfy the following formula (1).
0.95 × exp (0.039 × ET) −2 ≦ a ≦ 0.95 × exp (0.039 × ET) +2 (1)
here,
a is the content (μmol / g) of the alkali metal salt (A) in terms of alkali metal,
ET is the ethylene content of the ethylene-vinyl alcohol copolymer (mol%)
It is.

When there is more content of an alkali metal salt (A) than the range prescribed | regulated in the said (1) Formula, there exists a possibility that the hue of EVOH resin composition (F) may deteriorate. On the other hand, when it is less than the range specified in the above formula (1), the long run property and the adhesiveness may be deteriorated. It is more preferable to satisfy the following formula (1 ′), and it is more preferable to satisfy the following formula (1 ″).
0.95 × exp (0.039 × ET) −1.5 ≦ a ≦ 0.95 × exp (0.039 × ET) +1.5 (1 ')
0.95 × exp (0.039 × ET) −1 ≦ a ≦ 0.95 × exp (0.039 × ET) +1 (1 ")

  The content of the carboxylic acid or its salt (C) in the EVOH resin composition (F) of the present invention is 2 μmol / g or less in terms of carboxylic acid radical. Here, content of carboxylic acid or its salt (C) is the quantity of the carboxylic acid root extracted by being immersed in 95 degreeC water for 10 hours. Since it is assumed that most of the carboxylic acid and carboxylate contained in the EVOH resin composition (F) are extracted by immersing in 95 ° C. water for 10 hours, the above measured value is Numerical values corresponding to these total contents are shown. That is, the EVOH resin composition (F) is a resin composition having a very low content of carboxylic acid and carboxylate. The content of carboxylic acid or a salt thereof (C) is preferably 1.5 μmol / g or less, more preferably 1 μmol / g or less, and further preferably 0.5 μmol / g or less.

  The EVOH resin composition (F) used in the present invention may further contain a boron compound (B). The effects and types of the boron compound (B) are as described in the description of the method for producing the EVOH resin composition (F). The content of the boron compound (B) is preferably 1 to 200 μmol / g in terms of boron element. It is more preferably 2 μmol / g or more, and further preferably 3 μmol / g or more. Moreover, it is more preferable that it is 150 micromol / g or less, and it is further more preferable that it is 100 micromol / g or less.

  In addition, the EVOH resin composition (F) containing the phosphoric acid compound (D) balances long run properties during melt molding, color resistance, particularly color resistance during high temperature molding, and interlayer adhesion. Preferred above. The effects and types of the phosphoric acid compound (D) are as described in the description of the method for producing the EVOH resin composition (F). The upper limit of the content of the phosphoric acid compound (D) is preferably 5 μmol / g, more preferably 4 μmol / g, more preferably 3 μmol / g, and most preferably 1 in terms of phosphate radical. .5 μmol / g. When there are too many phosphate groups, there is a possibility that the thermal stability is lowered and the gelation tends to occur. On the other hand, the lower limit of the content of the phosphate compound (D) is preferably 0.05 μmol / g, more preferably 0.1 μmol / g, and even more preferably 0.15 μmol / g in terms of phosphate radical. g, optimally 0.2 μmol / g.

  At this time, the content (a: μmol / g) of the alkali metal salt (A) in terms of alkali metal in the EVOH resin composition (F) and the content of the phosphate compound (D) in terms of phosphate radical The ratio (a / d) to (d: μmol / g) is preferably 2.4-50. By doing so, it is possible to obtain a resin composition having good hue and thermal stability during melt molding. When the ratio (a / d) is less than 2.4, the thermal stability is lowered and the gelation tends to occur. On the other hand, when the ratio (a / d) exceeds 50, the hue may be deteriorated, and the thermal stability may be adversely affected. The ratio (a / d) is more preferably 40 or less, and even more preferably 30 or less.

  The EVOH resin composition (F) may contain an alkaline earth metal salt (E). However, in order to suppress coloration during melt molding, the content thereof is 0.001 in terms of alkaline earth metal. It is preferably 25 μmol / g or less. The blending of the alkaline earth metal salt (E) is as described in the description of the method for producing the EVOH resin composition (F). The content of the alkaline earth metal salt (E) is preferably 0.25 μmol / g or less in terms of alkaline earth metal, more preferably 0.1 μmol / g or less, and substantially More preferably, it is not contained.

  Suitable melt flow rate (MFR) of the EVOH resin composition (F) of the present invention (measured at 190 ° C. under a load of 2160 g; provided that the melting point is around 190 ° C. or exceeds 190 ° C. It is measured at a plurality of temperatures, and in a semi-log graph, the reciprocal absolute temperature is plotted on the horizontal axis and the melt flow rate is plotted on the vertical axis (logarithm) and extrapolated to 190 ° C.) is preferably 0.1 to 200 g / 10 min. It is. The lower limit of MFR is more preferably 0.2 g / 10 min. More preferably, 0.5 g / 10 min. Above, optimally 1 g / 10 min. That's it. Further, the upper limit of MFR is more preferably 50 g / 10 min. Or more preferably 30 g / 10 min. And optimally 15 g / 10 min. It is as follows. When the melt flow rate is smaller than the range, the inside of the extruder is in a high torque state at the time of molding, so that melt kneading becomes difficult. When the melt flow rate is larger than the range, the EVOH resin composition (F) is molded. The mechanical strength of the molded product thus formed is not preferable.

  The EVOH resin composition (F) of the present invention thus obtained may be molded alone, but is preferably molded after mixing with other resins. That is, a preferred embodiment of the present invention is a resin composition comprising 1 to 99% by weight of EVOH resin composition (F) and 1 to 99% by weight of another thermoplastic resin (G).

  The other thermoplastic resin (G) to be blended with the EVOH resin composition (F) can be appropriately selected according to the intended use, and is not particularly limited. Polyolefin (polyethylene, polypropylene, poly 1-butene, poly 4-methyl-1-pentene, ethylene-propylene copolymer, copolymer of ethylene and α-olefin having 4 or more carbon atoms, polyolefin and maleic anhydride Copolymers, ethylene-vinyl acetate copolymers, ethylene-vinyl alcohol copolymers, ethylene-acrylic acid ester copolymers, modified polyolefins obtained by graft-modifying these with unsaturated carboxylic acids or their derivatives), various nylons ( Nylon 6, nylon 66, nylon 6/66 copolymer, etc.), polyvinyl chloride, polyvinylidene chloride, polyester, polystyrene, polyacrylonitrile, polyurethane, polyacetal, modified polyvinyl alcohol resin and the like.

  Among these, it is preferable to use an ethylene-vinyl alcohol copolymer in applications where gas barrier properties are important in food packaging applications and the like. That is, in a particularly preferred embodiment, the other thermoplastic resin (G) is EVOH having an ethylene content of 5 to 60 mol% and a saponification degree of 99.2 to 100 mol%. By blending the EVOH resin composition (F) of the present invention with EVOH having such a high saponification degree, it is possible to suppress a decrease in transparency while improving the flexibility and secondary processability of EVOH. .

  Here, when the saponification degree of EVOH used as the other thermoplastic resin (G) is less than 99.2 mol%, the gas barrier property and melt stability of the resulting resin composition may be lowered. More preferably, it is 99.5 mol% or more, More preferably, it is 99.8 mol% or more. Further, when the ethylene content of EVOH used as the other thermoplastic resin (G) is less than 5 mol%, the melt moldability may be deteriorated. When the ethylene content exceeds 60 mol%, the gas barrier There is a risk that the property will be insufficient. The lower limit of the ethylene content is more preferably 15 mol% or more, and even more preferably 20 mol% or more. On the other hand, the upper limit of the ethylene content is more preferably 55 mol% or less, and even more preferably 50 mol% or less.

  The resin composition of the present invention is composed of 1 to 99% by weight of the EVOH resin composition (F) and 1 to 99% by weight of another thermoplastic resin (G). The compounding ratio of the EVOH resin composition (F) and the other thermoplastic resin (G) is adjusted according to the purpose. The EVOH resin composition (F) is preferably 3 to 97% by weight and the other thermoplastic resin (G) is preferably 3 to 97% by weight.

  When EVOH having an ethylene content of 5 to 60 mol% and a saponification degree of 99.2 to 100 mol% is used as the other thermoplastic resin (G), EVOH having a high saponification degree originally has In order to improve flexibility and secondary workability while maintaining good gas barrier properties, it is preferable to use EVOH having a high saponification degree as a main component. In this case, in order to obtain good barrier properties, the content of the EVOH resin composition (F) is preferably 50% by weight or less, and more preferably 30% by weight or less. On the other hand, in order to clarify the improvement effect of flexibility and secondary processability, the content of the EVOH resin composition (F) is preferably 5% by weight or more, more preferably 10% by weight or more. preferable. At this time, the remaining component is preferably EVOH having the high saponification degree.

  The resin composition of the present invention includes an antioxidant, a colorant, an ultraviolet absorber, a slip agent, an antistatic agent, a plasticizer, a cross-linking agent such as boric acid, an inorganic substance, and the like within a range that does not impair the effects exhibited by the present invention You may mix | blend various resins, such as various additives, such as a filler and an inorganic desiccant, and a super absorbent polymer.

  The blending means for obtaining the resin composition by melt-kneading the EVOH resin composition (F) and other thermoplastic resin (G), and in some cases the above additives, is not particularly limited, and is a known method. Either can be adopted. Among these, the melt kneading method using a single-screw or twin-screw extruder (same direction or different direction), an intensive mixer, a continuous intensive mixer and the like is preferable from the viewpoint of process simplicity and cost. In particular, the EVOH resin composition (F) and other thermoplastic resin (G) are dry blended, and granulated and dried with a single screw or twin screw extruder or the like. In order to make the dispersion state uniform, it is preferable to use an extruder having a high degree of kneading during the kneading pelletization operation. The kneading temperature is preferably in the range of 150 to 280 ° C. In order to prevent oxidation of the resulting resin composition, it is preferable that the hopper port be sealed with nitrogen and extruded at a low temperature. The longer the kneading time, the better results can be obtained, but 0.1 to 20 minutes is preferable from the viewpoint of preventing oxidation of the resin composition and production efficiency.

  The resin composition of the present invention thus obtained is molded into various molded products such as films, sheets, containers, pipes and fibers by melt molding. As the melt molding method, extrusion molding, inflation extrusion, blow molding, injection molding, melt spinning and the like are possible. The melting temperature varies depending on the melting point of the copolymer, but is preferably about 150 to 270 ° C. At this time, the resin composition of the present invention may be once pelletized and used for molding, or the EVOH resin composition (F) and another thermoplastic resin (G) may be dry blended and directly used for molding. May be. These molded products can be pulverized and molded again for reuse. Moreover, it is also possible to perform secondary processing by uniaxially or biaxially stretching a film, sheet, fiber or the like, or thermoforming.

  Hereinafter, the molding method will be described in detail. The resin composition of the present invention referred to here is an EVOH resin composition (F) alone, an EVOH resin composition (F), and another thermoplastic resin (G). Both of the resin compositions to be included are included.

  The resin composition of the present invention can be used as a molded product composed of only a single layer of the resin composition. However, since it has excellent interlayer adhesion, a multilayer structure comprising at least one layer of the resin composition. It is also suitable. The layer structure of the multilayer structure is represented by X / T, T / X / T, X / Ad / T, T, where X is the resin composition of the present invention, Ad is the adhesive resin, and T is the thermoplastic resin. / Ad / X / Ad / T, T / Ad / X / T, T / Ad / T / Ad / X / T, and the like, but are not limited thereto. Each of the layers shown here may be a single layer or may be a multilayer according to circumstances.

  The method for producing the multilayer structure shown above is not particularly limited. For example, a method of melt-extruding a thermoplastic resin on a molded article (film, sheet, etc.) comprising the resin composition of the present invention, and conversely, the resin composition and another thermoplastic resin on a substrate such as a thermoplastic resin And a method of co-extrusion or co-injection of a thermoplastic resin and the resin composition of the present invention, and a molded product obtained from the resin composition of the present invention and films and sheets of other substrates And a method of laminating using a known adhesive such as an organic titanium compound, an isocyanate compound, and a polyester compound. Among these, the method of co-extrusion or co-injection is preferable.

  The method of coextrusion molding of the resin composition of the present invention and the thermoplastic resin is not particularly limited, and a multi-manifold merging method T-die method, a feed block merging method T-die method, an inflation method and the like are exemplified as suitable ones. . Further, the method of co-injection molding is not particularly limited, and a general method can be used.

  The thermoplastic resin used for laminating with the resin composition of the present invention includes linear low density polyethylene, low density polyethylene, medium density polyethylene, high density polyethylene, ethylene-vinyl acetate copolymer, ethylene-vinyl alcohol. Copolymers, ethylene-propylene copolymers, polypropylene, propylene-α-olefin copolymers (α-olefins having 4 to 20 carbon atoms), olefins such as polybutene and polypentene, or copolymers thereof, polyethylene terephthalate, etc. Polyester, polyester elastomer, polyamide resin such as nylon-6, nylon-6,6, polystyrene, polyvinyl chloride, polyvinylidene chloride, acrylic resin, vinyl ester resin, polyurethane elastomer, polycarbonate, chlorinated polyethylene, salt For example, basic polypropylene.

  When laminating the resin composition of the present invention and the thermoplastic resin, the adhesive resin in the case of using the adhesive resin is preferably an adhesive resin made of a carboxylic acid-modified polyolefin. Here, the carboxylic acid-modified polyolefin is a modified olefinic polymer containing a carboxyl group obtained by chemically (for example, by addition reaction or graft reaction) bonding an ethylenically unsaturated carboxylic acid or its anhydride to an olefin polymer. Refers to coalescence. In addition, the olefin polymer is a polyethylene (low pressure, medium pressure, high pressure), a polyolefin such as linear low density polyethylene, polypropylene, boribten, or the like, a comonomer (vinyl ester, non-polymer) capable of copolymerizing the olefin and the olefin. Means a copolymer with a saturated carboxylic acid ester and the like, for example, an ethylene-vinyl acetate copolymer, an ethylene-acrylic acid ethyl ester copolymer, and the like. Of these, linear low density polyethylene, ethylene-vinyl acetate copolymer (vinyl acetate content 5-55 wt%), ethylene-acrylic acid ethyl ester copolymer (acrylic acid ethyl ester content 8-35 wt. %), Linear low density polyethylene and ethylene-vinyl acetate copolymers are particularly preferred. Examples of the ethylenically unsaturated carboxylic acid or its anhydride include ethylenically unsaturated monocarboxylic acid, its ester, ethylenically unsaturated dicarboxylic acid, its mono or diester, and its anhydride. Among these, ethylenically unsaturated dicarboxylic acid Anhydrides are preferred. Specific examples include maleic acid, fumaric acid, itaconic acid, maleic anhydride, itaconic anhydride, maleic acid monomethyl ester, maleic acid monoethyl ester, maleic acid diethyl ester, and fumaric acid monomethyl ester. Acid is preferred.

  The multilayer structure obtained as described above can be used as various molded articles such as packaging films and containers. Such a molded article has a good appearance, excellent flexibility, suppressed odor generation, and excellent interlayer adhesion, so various foods such as packaging films, deep-drawn containers, cup-shaped containers, bottles, etc. It is suitably used as a packaging container. In addition to food packaging containers, they are also used for applications such as fuel containers, fuel pipes, hot water circulation pipes for floor heating, and wallpaper.

  A suitable use of the resin composition of the present invention is a blow molded container. As the blow molding method, either extrusion blow molding or injection blow molding can be employed. As extrusion blow molding, it is possible to cut and cool a pre-extruded pipe and then heat and blow mold it, but so-called direct blow molding method in which the extruded tubular molten parison is blow molded as it is Is preferred. Further, as injection blow molding, a method may be used in which a bottomed parison is injection molded in advance and blow molded while maintaining a high temperature during cooling, or is heated again after blow and blow molded. When performing such blow molding, conventionally, during the long run molding, the resulting bottle may be fuzzy, colored, or streaky, but by using the resin composition, the occurrence of these problems is suppressed. be able to. In particular, when the die temperature in the extrusion blow molding or the nozzle temperature in the injection blow molding is 250 ° C. or higher, such a problem is likely to occur, so that the practical advantage of employing the resin composition is great.

  The blow molded container of the present invention may be composed of a single layer of the resin composition, or may be composed of a multilayer structure having the resin composition layer and another resin layer. . Since the resin composition is excellent in interlayer adhesion, a multilayer structure is preferable. The layer structure of the multilayer structure is represented by E / T, T / E / T, E / Ad / T, T, where E is the resin composition, Ad is the adhesive resin, and T is the other thermoplastic resin. Examples include, but are not limited to, / Ad / E / Ad / T, T / E / T / E / T, and the like. Each of the layers shown here may be a single layer or, depending on the case, a multilayer. The thickness of each said layer is about 5-300 micrometers in the said resin composition layer and adhesive resin layer, and is about 20-5000 micrometers in another thermoplastic resin.

  As a method for producing a blow molded container having such a multilayer structure, coextrusion blow molding or co-injection blow molding is suitably employed.

  As a method of coextrusion blow molding, a multilayer extruder having at least two extruders is used, and the resin composition, other thermoplastic resin and, if necessary, an adhesive resin are supplied to separate extruders. Kneading and melt-extrusion are performed separately, and each layer is extruded so as to be closely joined and merged inside the die for forming a multi-layer parison or immediately after discharging from the die to obtain a tubular multi-layer parison, and then this parison is blown in a molten state Thus, a so-called direct blow molding method for obtaining a multilayer container is preferable. The other thermoplastic resin used in coextrusion blow molding, particularly direct blow molding, is not particularly limited, but is preferably polyolefin. Among polyolefins, polyethylene and polypropylene are preferably used. At this time, it is preferable to have an adhesive resin layer between the fat composition layer and the polyolefin layer. Particularly suitable layer configurations are E / Ad / T, T / Ad / E / Ad, where E is the resin composition, Ad is the adhesive resin, and T is the other thermoplastic resin (polyolefin). / T.

  Moreover, as a method of co-injection blow molding, a multilayer parison is obtained by injection molding using a multilayer injection molding machine having at least two extruders, and then blow molding during cooling or reheating after cooling. This method is preferably employed. When the multilayer parison is blow-molded, stretch blow molding, particularly biaxial stretch blow molding is preferred. The other thermoplastic resin used in the co-injection blow molding is not particularly limited, but is preferably polyester or polyamide. In particular, when a polyester represented by polyethylene terephthalate is used, it is preferable because a blow molded container having excellent strength can be obtained by biaxial stretch blow molding.

  In the co-injection blow-molded container of the present invention, an adhesive resin layer may be disposed between the resin composition layer and another thermoplastic resin layer, or both may be brought into direct contact with each other. As a particularly preferred layer structure, when the resin composition is represented by E, the adhesive resin is represented by Ad, and another thermoplastic resin (here, polyester or the like) is represented by T, T / E / T, T / Ad / E / Ad / T, T / E / T / E / T are mentioned. Especially, the structure which consists only of the said resin composition layer and another thermoplastic resin layer is preferable, and a layer structure like T / E / T and T / E / T / E / T is illustrated as a suitable thing. . That is, a layer structure in which other thermoplastic resin layers, particularly layers made of polyethylene terephthalate are arranged on both sides of the resin composition layer is preferable. Thus, even in the case of a layer configuration in which an adhesive resin layer is not disposed between the resin composition layer and another thermoplastic resin layer, the co-injection blow molded container of the present invention has good interlayer adhesion, Excellent impact resistance. That is, even when the co-injection blow-molded container receives an impact or the like, the occurrence of delamination between the resin composition layer and another thermoplastic resin layer can be suppressed.

  Since the resin composition of the present invention is excellent in secondary processability, it is preferable to further secondary-process a molded product obtained by melt molding. Examples of the secondary processing method include a method of stretching a film or sheet in a uniaxial or biaxial direction, a method of thermoforming, a method of rolling, and the like. Moreover, the co-injection-molded parison can be blow-molded. Among them, it is particularly suitable to use in a thermoformed container obtained by secondary processing of a multilayer film or sheet, particularly a deep drawn container. In particular, in the case of a container having a deep squeezing depth and a complicated container shape, it is preferable to use a multilayer structure having the resin composition layer of the present invention that is excellent in flexibility, secondary workability and interlayer adhesion. It is.

  Another suitable use of the resin composition of the present invention is a thermoformed container. Thermoforming as used in this invention means shape | molding in a metal mold | die shape, after heating and softening a film or a sheet | seat. As a molding method, vacuum or compressed air is used, and if necessary, a plug is further formed into a mold shape (straight method, drape method, air slip method, snapback method, plug assist method, etc.) or press molding. The method etc. are mentioned. Various molding conditions such as the molding temperature, the degree of vacuum, the pressure of compressed air, or the molding speed are appropriately set depending on the plug shape, the mold shape, or the properties of the raw material film or sheet. Thermoformed containers such as cups and trays obtained by thermoforming in this way are suitably used as various containers, particularly food packaging containers.

  EXAMPLES Hereinafter, although an Example demonstrates this invention further in detail, this invention is not limited to this Example. Hereinafter, “%” and “parts” are based on weight unless otherwise specified. In addition, all the water used ion-exchange water.

(1) Quantification of alkali metal salt (A) and alkaline earth metal salt (E) The pellets of the dry EVOH resin composition (F) were pulverized by freeze pulverization. The obtained pulverized EVOH resin composition (F) was sieved with a sieve having a nominal size of 1 mm (standard fluid standard JIS Z-8801 compliant). 10 g of the EVOH resin composition (F) powder that has passed through the above sieve and 50 mL of 0.01 N hydrochloric acid aqueous solution are put into a conical flask with a 100 mL stopper, attached with a cooling condenser, stirred at 95 ° C. for 10 hours, and heated to extract did. 2 mL of the obtained extract was diluted with 8 mL of ion exchange water. The diluted extract was quantitatively analyzed using an ion chromatography IC7000 manufactured by Yokogawa Electric Corporation, and the amounts of Na ions, K ions, Mg ions and Ca ions were quantified. For the determination, calibration curves prepared using a sodium chloride aqueous solution, a potassium chloride aqueous solution, a magnesium chloride aqueous solution, and a calcium chloride aqueous solution were used. From the amounts of Na ions, K ions, Mg ions and Ca ions thus obtained, the amounts of alkali metal salt (A) and alkaline earth metal salt (E) contained in the dried EVOH pellets were obtained in terms of metal element. .
Ion chromatography measurement conditions:
Column: ICS-C25 manufactured by Yokogawa Electric Corporation
Eluent: aqueous solution containing 5.0 mM tartaric acid and 1.0 mM 2,6-pyridinedicarboxylic acid Measurement temperature: 40 ° C.
Eluent flow rate: 1 mL / min.
Sample injection amount: 50 μL

(2) Quantification of carboxylic acid or salt thereof (C) The pellets of the dried EVOH resin composition (F) were pulverized by freeze pulverization. The obtained pulverized EVOH resin composition (F) was sieved with a sieve having a nominal size of 1 mm (standard fluid standard JIS Z-8801 compliant). 10 g of EVOH resin composition (F) powder and 50 mL of ion-exchanged water that passed through the above sieve were put into a 100 mL Erlenmeyer flask with a stopper, attached with a cooling condenser, and stirred and extracted at 95 ° C. for 10 hours. 2 mL of the obtained extract was diluted with 8 mL of ion exchange water. The diluted extract was quantitatively analyzed using an ion chromatography IC7000 manufactured by Yokogawa Electric Corporation, and the amount of carboxylic acid (acetic acid) ions was quantified to obtain a carboxylic acid radical. Note that a calibration curve prepared using an aqueous acetic acid solution was used for quantification.
Ion chromatography measurement conditions:
Column: SCS5-252 manufactured by Yokogawa Electric Corporation
Eluent: 0.1% phosphoric acid aqueous solution Measurement temperature: 40 ° C
Eluent flow rate: 1 mL / min.
Sample injection amount: 50 μL

(3) Quantification of phosphoric acid compound (D) The pellets of the dry EVOH resin composition (F) were pulverized by freeze pulverization. The obtained pulverized EVOH resin composition (F) was sieved with a sieve having a nominal size of 1 mm (standard fluid standard JIS Z-8801 compliant). 10 g of EVOH resin composition (F) powder and 50 mL of 0.01 N hydrochloric acid aqueous solution which passed through the above sieve were put into a 100 mL conical flask with a stopper, attached with a cooling condenser, and stirred and extracted at 95 ° C. for 4 hours. The obtained extract was quantitatively analyzed using an ion chromatography IC7000 manufactured by Yokogawa Electric Corporation, and the amount of phosphate ions was quantified to obtain the amount of phosphate radicals. For the determination, a calibration curve prepared using an aqueous sodium dihydrogen phosphate solution was used.
Ion chromatography measurement conditions:
Column: ICS-A23 manufactured by Yokogawa Electric Corporation
Eluent: Aqueous solution containing 2.5 mM sodium carbonate and 1.0 mM sodium bicarbonate Measurement temperature: 40 ° C
Sample injection amount: 50 μL

(4) Measurement of saponification degree (NMR method)
Dry EVOH pellets were ground by freeze grinding. The obtained pulverized EVOH was sieved with a sieve having a nominal size of 1 mm (conforming to standard sieve standard JIS Z-8801). 5 g of EVOH powder that passed through the above sieve was immersed in 100 g of ion-exchanged water, stirred at 85 ° C. for 4 hours, then drained and dried twice. Using the obtained powder EVOH after washing, NMR was measured under the following measurement conditions, and the degree of saponification was determined by the following analysis method.

Measurement conditions: Device name: JEOL Superconducting Nuclear Magnetic Resonance Device Lambda 500
Observation frequency: 500 MHz
Solvent: DMSO-d6
Polymer concentration: 4% by weight
Measurement temperature: 40 ° C and 95 ° C
Number of integrations: 600 times Pulse delay time: 3.836 seconds Sample rotation speed: 10-12 Hz
Pulse width (90 ° pulse): 6.75 μsec

・ Analysis method In the measurement at 40 ° C., a hydrogen peak in the water molecule is observed around 3.3 ppm, and the methine hydrogen peak of the vinyl alcohol unit of EVOH has a portion of 3.1 to 3.7 ppm. It overlapped. On the other hand, in the measurement at 95 ° C., the overlap generated at 40 ° C. is eliminated, but the hydrogen peak of the hydroxyl group of the vinyl alcohol unit of EVOH present in the vicinity of 4 to 4.5 ppm is methine of the vinyl alcohol unit of EVOH. It overlapped with a portion of 3.7 to 4 ppm of the hydrogen peak. That is, for the quantification of EVOH vinyl alcohol unit methine hydrogen (3.1-4 ppm), in order to avoid overlap with the hydrogen peak of water or hydroxyl group, about 3.1-3.7 ppm portion, The measurement data of ° C. was adopted, the measurement data of 40 ° C. was adopted for the portion of 3.7 to 4 ppm, and the total amount of the methine hydrogen was quantified as the total value thereof. It is known that the hydrogen peak of water or hydroxyl shifts to the high magnetic field side by increasing the measurement temperature.

Therefore, it analyzed using the measurement result of both 40 degreeC and 95 degreeC as follows. From the spectrum measured at 40 ° C., the integrated value (I ₁ ) of the peak of chemical shift of 3.7 to 4 ppm and the integrated value (I ₂ ) of the peak of chemical shift of 0.6 to 1.8 ppm are obtained. On the other hand, from the spectrum measured at 95 ° C., the integrated value (I ₃ ) of the peak of chemical shift of 3.1 to 3.7 ppm, the integrated value (I ₄ ) of the peak of chemical shift of 0.6 to 1.8 ppm and The integrated value (I ₅ ) of the peak of chemical shift of 1.9 to 2.1 ppm is determined. Here, the peak of chemical shift of 0.6 to 1.8 ppm is mainly derived from methylene hydrogen, and the peak of chemical shift of 1.9 to 2.1 ppm is in unsaponified vinyl acetate units. It is derived from methyl hydrogen. The saponification degree was calculated from these integral values by the following formula.

(5) Measurement of moisture content of water-containing EVOH pellets Using a HR73 halogen moisture content analyzer manufactured by METLER, the moisture content of EVOH pellets was measured under the conditions of a drying temperature of 180 ° C, a drying time of 20 minutes, and a sample amount of about 10 g.

(6) Measurement of carbon dioxide concentration A carbon dioxide sensor (CE-2041) was connected to a portable ion / pH meter (IM-22P) manufactured by Toa Denpa Kogyo Co., Ltd., and the carbon dioxide concentration in the solution was measured.

(7) Single-layer film-forming test Dry EVOH resin composition (F) or pellets of resin composition comprising dry EVOH resin composition (F) and EVOH having a high saponification degree 20 mm extruded by Toyo Seiki Seisakusho Co., Ltd. A single layer film is obtained using the machine D2020 (D (mm) = 20, L / D = 20, compression ratio = 2.0, screw: full flight) under the following two conditions. It was.
Condition 1: Film forming extrusion temperature at 220 ° C .: C1 / C2 / C3 / Die = 175/200/220/220 ° C.
Screw rotation speed: 40rpm
Discharge rate: 1.3 kg / hr
Take-up roll temperature: 80 ° C
Take-up roll speed: 3.1 m / min.
Film thickness: 20 μm
Condition 2: Film forming extrusion temperature: C1 / C2 / C3 / Die = 175/230/250/250 ° C.
Screw rotation speed: 40rpm
Discharge rate: 1.4kg / hr
Take-up roll temperature: 80 ° C
Take-up roll speed: 3.1 m / min.
Film thickness: 20 μm

(7-a) Color resistance The single-layer film produced by the above-described film formation at 220 ° C. and film formation at 250 ° C. was wound around a paper tube, and the degree of coloration of the film end face was determined with the naked eye as follows.
Judgment: Standard A: No coloring B: Slightly yellow C: Yellowing

(7-b) 48-hour long-run property In film formation at 220 ° C., the film after 48 hours from the start of single-layer film formation was sampled, and the gel-like irregularities (those of about 100 μm or more that can be confirmed with the naked eye) in the film were counted. .
The number of bumps was converted to the number per 1.0 m ² and judged as follows.
Determination: Standard A: Less than 20 B: 20 or more and less than 40 C: 40 or more and less than 60 D: 60 or more

(7-c) 60-hour long-run property In film formation at 220 ° C., the film after 60 hours from the start of single-layer film formation was sampled, and gel-like irregularities (those of about 100 μm or more that can be confirmed with the naked eye) in the film were counted. .
The number of bumps was converted to the number per 1.0 m ² and judged as follows.
Determination: Standard A: Less than 20 B: 20 or more and less than 40 C: 40 or more and less than 60 D: 60 or more

(8) Evaluation of high-temperature coloring property Pellet 5 g of dry EVOH resin composition (F) or resin composition comprising dry EVOH resin composition (F) and EVOH having a high saponification degree is heated at 250 ° C. with a heat compression press apparatus. A disk-shaped sample having a thickness of 2 mm was prepared by heating and melting for 2 minutes, and the hue was visually evaluated as follows.
Judgment: Criteria A: Almost no coloration.
B: Slightly yellowed.
C: Yellowish.

(9) Adhesive strength test Dry EVOH resin composition (F) or pellets of a resin composition comprising dry EVOH resin composition (F) and EVOH having a high saponification degree, linear low density polyethylene (LLDPE; Mitsui Chemicals) 3 types and 5 layers multilayer film (LLDPE / Tie / resin composition / Tie /) by the following method using a product made by Co., Ltd., ULT ZEXX 2022L) and an adhesive resin (Tie; manufactured by SUMIKA. ATOCHEM Co. Ltd, Bondine TX8030). LLDPE = 50 μ / 10 μ / 10 μ / 10 μ / 50 μ) was obtained.
Extruder and T-die specifications used in this test are as follows.
Extruder:
20φ extruder for resin composition Laboratory machine ME type CO-EXT (manufactured by Toyo Seiki)
25φ extruder for Tie P25-18AC (Osaka Seiki)
32φ extruder for LLDPE GF-32-A (Plastic Engineering Laboratory)
Resin composition extrusion temperature:
C1 / C2 / C3 / die = 175/210/220/220 ° C.
Tie extrusion temperature:
C1 / C2 / C3 / die = 100/160/220/220 ° C.
LLDPE extrusion temperature:
C1 / C2 / C3 / die = 150/200/210/220 ° C.
T-die: 300mm width coat hanger die (Plastic Engineering Laboratory)

(9-a) Adhesive strength immediately after film formation Immediately after film formation, the obtained multilayer film was cut out to 150 mm in the MD direction and 10 mm in the TD direction, and then immediately by an autograph (manufactured by Shimadzu Corporation, DCS-50M). T-type peel strength measurement was performed. In the measurement, the interlayer adhesive strength between Tie on the cooling roll side of the multilayer film and the resin composition was measured.

(9-b) Adhesive strength after one week from film formation The above-prepared sample made of a multilayer film having a length of 150 mm and a width of 10 mm was left in a constant temperature and humidity chamber at 23 ° C.-50% RH for one week. Using the sample, T-type peel strength measurement was performed in a constant temperature and humidity chamber of 23 ° C.-50% RH by an autograph (manufactured by Shimadzu Corporation, DCS-50M). In the measurement, the interlayer adhesive strength between Tie on the cooling roll side of the multilayer film and the resin composition was measured.
(10) Odor test Dry EVOH resin composition (F) or dry EVOH resin composition (F) and 10 g of resin composition pellets composed of EVOH having a high saponification degree and 10 mL of ion-exchanged water are placed in a 100 mL glass screw tube. It was put in and sealed with a lid. Then, after putting in 90 degreeC safe vent dryer (dryer) and heat-extracting for 15 hours, it stood at room temperature for 30 minutes and cooled the said screw pipe | tube. After cooling, the lid of the screw tube was opened, and the odor of the resulting extract was evaluated as follows by using five monitors.
Judgment: Criteria A: No odor is felt.
B: A slight odor is felt.
C: Odor is felt.

Example 1
[Production and Evaluation of EVOH Resin Composition (F)]
As the saponification reactor, a bubble bell tower having a tower diameter of 0.85 m and 20 stages was used. From the top of this bubble bell tower, a methanol solution (EVAc concentration: 45% by weight) of an ethylene vinyl alcohol copolymer (hereinafter referred to as EVAc) having an ethylene content of 51 mol% was added to 1.3 t / hour, and water was added. A methanol solution containing sodium hydroxide (concentration of sodium hydroxide: 15% by weight, water content: 5.8% by weight) was fed at 50 kg / hour. The water content relative to EVAc was about 5000 ppm. Further, 115 ° C. methanol vapor was blown into the tower at 1.1 t / hour from the bottom of the tower, and methyl acetate produced as a by-product was distilled from the top of the tower together with part of the methanol. At this time, the temperature in the tower was 110 to 115 ° C., the pressure was 5.5 kg / cm ² (about 0.54 MPa), and the residence time of the raw material in the tower was about 30 minutes. In this way, a methanol solution of EVOH having a saponification degree of 96.0 mol% was obtained from the bottom of the tower.

  A water-methanol mixed vapor was further blown into this solution, and the water-methanol mixed vapor was distilled off. A solution of EVOH in a methanol-water mixed solvent (methanol / water = 9/1, weight ratio) (EVOH concentration: 36). % By weight). This solution was discharged from a die having a 2 mm diameter hole into a coagulation bath composed of a methanol-water mixed solvent (methanol / water = 10/90, weight ratio) at 5 ° C. to be solidified into a strand. This strand was cut with a cutter to obtain pellets having a length of 2.5 to 3.5 mm.

  2.4 kg of the hydrous pellets thus obtained and 24 L of ion-exchanged water were placed in a plastic container having a height of 400 mm and an open diameter of 370 mm, washed with stirring at 25 ° C. for 2 hours, and then drained. Repeated twice. Next, an operation of adding 24 L of 1 g / L acetic acid aqueous solution to 2.4 kg of water-containing pellets, washing the mixture with stirring at 25 ° C. for 2 hours, and then removing the liquid was repeated twice. Further, 24 L of ion exchange water was added to 2.4 kg of the water-containing pellets, and the operation of washing with stirring at 25 ° C. for 2 hours and then draining was repeated 6 times. As a result of measuring the conductivity of the cleaning liquid after the sixth cleaning with CM-30ET manufactured by Toa Denpa Kogyo, the conductivity of the cleaning liquid was 3 μS / cm. The water content of the obtained EVOH pellets was 60% by weight.

  Next, 12 L of ion-exchanged water was put into a plastic container having a height of 400 mm and an open diameter of 370 mm. A silicon tube (inner diameter 7 mm, outer diameter 10 mm) was put into the ion-exchanged water in the container, and 0.5 L, 1 L / min. Bubbling at a speed of carbon dioxide was blown. Carbon dioxide was supplied using a carbon dioxide cylinder (liquefied carbon dioxide 30 kg manufactured by Nippon Carbon Co., Ltd.) and a flow meter (Model RK-1600R manufactured by KOFLOC). In the water into which the carbon dioxide gas was blown, 3.24 g of potassium hydrogen carbonate and 1.32 g of potassium dihydrogen phosphate were dissolved, and further for 1 hour, 1 L / min. Carbon dioxide was continuously blown at a speed of. The treatment solution had a potassium hydrogen carbonate content of 0.27 g / L and a potassium dihydrogen phosphate content of 0.11 g / L. Moreover, when the pH of the said processing liquid after blowing in carbon dioxide gas for 1 hour was measured using the pH meter (Metler MA235), the pH of the said processing liquid was 5.3.

  Next, the blowing speed is 1 L / min. Then, while continuing to blow carbon dioxide, 1.4 kg of the above water-containing pellets were added to the treatment liquid, and immersed and stirred at 25 ° C. for 4 hours. Further, when the pH of the treatment liquid was measured every hour from the start of the treatment to the end of the treatment, the pH of the treatment liquid remained at 5.3 and did not vary at any measurement time. It was 20 mmol / L when the carbon dioxide gas density | concentration in a process liquid was analyzed. After being immersed in the treatment solution for 4 hours and stirring, the obtained pellets were immediately drained and dried with hot air at 80 ° C. for 3 hours and subsequently at 105 ° C. for 16 hours to obtain a dried EVOH resin composition ( F) A pellet was obtained.

  The alkali metal salt (A) in the obtained dried EVOH resin composition (F) pellets was a potassium salt, and the content of the alkali metal salt was 4.92 μmol / g in terms of metal element. Neither magnesium salt nor calcium salt was detected in the alkaline earth metal salt (E), and the content of the alkaline earth metal salt (E) was 0 μmol / g in terms of metal element. The content of carboxylic acid or its salt (C) was 0 μmol / g in terms of acetate radical. The content of the phosphoric acid compound (D) was 0.80 μmol / g in terms of phosphate radical. Moreover, MFR of the said dry EVOH resin composition (F) pellet is 5.8 g / 10min. (Under 190 ° C. and 2160 g load).

  Using the dry EVOH resin composition (F) pellets, a single-layer film was produced according to the above-described method, and a test for coloring resistance and long run property was performed. The evaluation result of the color resistance at the time of film formation at 220 ° C. in this example was A. The evaluation result of the coloration resistance during film formation at 250 ° C. was A. In addition, the 48-hour long run evaluation result was A, and the 60-hour long run evaluation result was B.

  When the high temperature coloring property evaluation test was performed according to the above-mentioned method using the said dry EVOH resin composition (F) pellet, evaluation was A determination. Moreover, when the odor test was done according to the above-mentioned method using the said dry EVOH resin composition (F) pellet, all five monitors did not feel odor, and evaluation was A determination.

  Moreover, when the adhesive strength test was performed according to the above-mentioned method using the dry EVOH resin composition (F) pellets, the adhesive strength immediately after film formation was 600 g / 15 mm, and adhesion after one week had elapsed since film formation. The strength was 900 g / 15 mm, and good adhesive strength was obtained in all cases.

Comparative Example 1
The washed water-containing pellets obtained in the same manner as in Example 1 were immersed in 12 L of an aqueous solution containing 0.20 g / L of acetic acid and 0.07 g / L of potassium hydrogen phosphate at 25 ° C. for 4 hours and stirred. did. Thereafter, the liquid was removed, and hot-air drying was performed at 80 ° C. for 3 hours and subsequently at 105 ° C. for 16 hours to obtain dry EVOH resin composition pellets.

  The alkali metal salt (A) in the obtained dried EVOH resin composition pellets was a potassium salt, and the content of the alkali metal salt (A) was 0.57 μmol / g in terms of metal element. Neither magnesium salt nor calcium salt was detected in the alkaline earth metal salt (E), and the content of the alkaline earth metal salt (E) was 0 μmol / g in terms of alkaline earth metal element. The content of carboxylic acid or its salt (C) was 3.2 μmol / g in terms of acetate radical. The content of the phosphoric acid compound (D) was 0.40 μmol / g in terms of phosphate radical. The MFR of the dried EVOH resin composition pellet is 5.8 g / 10 min. (Under 190 ° C. and 2160 g load).

  Using the dry EVOH resin composition pellets, a single-layer film was produced according to the above-described method, and a test for coloring resistance and long run property was performed. The evaluation result of the color resistance at the time of film formation at 220 ° C. in this comparative example was B determination. The evaluation result of the color resistance at the time of film formation at 250 ° C. was B judgment. In addition, the 48-hour long run evaluation result was A, and the 60-hour long run evaluation result was B.

  When the high temperature coloring property evaluation test was performed according to the above-mentioned method using the said dry EVOH resin composition pellet, evaluation was B determination. Moreover, when the odor test was performed according to the above-mentioned method using the said dry EVOH resin composition pellet, all five monitors felt odor and evaluation was C determination.

  Moreover, when the adhesive strength test was performed according to the above-mentioned method using the dry EVOH resin composition pellets, the adhesive strength immediately after film formation was 230 g / 15 mm, and the adhesive strength after one week from film formation was 650 g. / 15 mm.

Example 2
[Production and Evaluation of Resin Composition]
0.50 kg of the EVOH resin composition (F) pellet obtained in Example 1, 3.4 μmol / g of potassium salt in terms of potassium element weight, and 1.1 μmol / g of phosphorus compound in terms of phosphate radical After dry blending 2.00 kg of EVOH (saponification degree 99.9%) with an ethylene content of 32 mol%, it is melt-kneaded with a twin-screw extruder (manufactured by Toyo Seiki Seisakusho Co., Ltd.), pelletized, and resin composition I got a thing. The melt kneading conditions are shown below.

Specifications of twin screw extruder (manufactured by Toyo Seiki Seisakusho) Model: Twin screw extruder L / D: 25
Diameter: 26mmφ
Screw: Fully meshed in the same direction Number of die holes: 2 holes (3mmφ)
Kneading conditions Rotation speed: 150rpm
Extrusion temperature: C1 / C2 / C3 / C4 / C5 / Die
= 180/200/220/220/220/220 ° C.
Discharge rate: 2.3 kg / hr

  Using the resin composition pellets obtained by melt-kneading, a single-layer film was prepared according to the above-described method, and tests for color resistance and long run properties were performed. The evaluation result of the color resistance at the time of film formation at 220 ° C. in this example was A. The evaluation result of the coloration resistance during film formation at 250 ° C. was A. In addition, the 48-hour long run evaluation result was A, and the 60-hour long run evaluation result was B.

  When the high temperature colorability evaluation test was performed according to the above-mentioned method using the resin composition pellets obtained by melt kneading, the evaluation was A judgment. Moreover, when the odor test was performed according to the above-mentioned method using the said resin composition pellet, all five monitors did not feel odor, and evaluation was A determination.

  Moreover, when the adhesive strength test was performed according to the above-mentioned method using the resin composition pellets obtained by melt-kneading, the adhesive strength immediately after film formation was 623 g / 15 mm, and one week after the film formation. The adhesive strength was 751 g / 15 mm, and good adhesive strength was obtained in all cases.

Comparative Example 2
In the same manner as in Example 2, 0.50 kg of dry EVOH resin composition pellets obtained in Comparative Example 1 and potassium salt were converted to 3.4 μmol / g in terms of potassium element weight, and phosphorus compound was converted to 1.1 μmol in terms of phosphate radical. After dry blending with 2.00 kg of EVOH (saponification degree: 99.9%) containing 32 mol% of ethylene containing / g, the mixture was melt-kneaded and pelletized.

  Using the resin composition pellets obtained by melt-kneading, a single-layer film was prepared according to the above-described method, and tests for color resistance and long run properties were performed. The evaluation result of the coloring resistance at the time of film formation at 220 ° C. in this comparative example was A. The evaluation result of the color resistance at the time of film formation at 250 ° C. was B judgment. In addition, the 48-hour long run evaluation result was A, and the 60-hour long run evaluation result was B.

  When the high temperature colorability evaluation test was performed according to the above-mentioned method using the resin composition pellets obtained by melt kneading, the evaluation was A judgment. Moreover, when the odor test was performed according to the above-mentioned method using the said resin composition pellet, 3 persons felt odor out of 5 monitors, and evaluation was B determination.

  Moreover, when the adhesive strength test was performed according to the above-mentioned method using the resin composition pellets obtained by melt-kneading, the adhesive strength immediately after film formation was 560 g / 15 mm, and one week after the film formation. The adhesive strength was 716 g / 15 mm.

Example 3
The pellet obtained in Example 2 was used as a resin composition layer, and a linear low density polyethylene (LLDPE) resin (“Ultzex 3520L” manufactured by Mitsui Chemicals, Inc.) was used as the outermost layer. “Admer SF600” manufactured by Mitsui Chemicals, Inc. "} As an adhesive (AD) layer, and three types and five layers (LLDPE / AD / resin composition / AD / LLDPE = 40μ / 5μ / 20μ / 5μ /) using a co-extruder equipped with a T-die. 40 μ), a film for thermoforming having an overall thickness of 110 μm was obtained.
The coextrusion molding conditions are as follows.
Extruder:
20φ extruder for resin composition Laboratory machine ME type CO-EXT (manufactured by Toyo Seiki)
25φ extruder for AD P25-18AC (manufactured by Osaka Seiki)
32φ extruder for LLDPE GF-32-A (Plastic Engineering Laboratory)
Resin composition extrusion temperature:
C1 / C2 / C3 / die = 175/210/220/220 ° C.
AD extrusion temperature:
C1 / C2 / C3 / die = 100/160/220/220 ° C.
LLDPE extrusion temperature:
C1 / C2 / C3 / die = 150/200/210/220 ° C.
T-die: 300mm width coat hanger die (Plastic Engineering Laboratory)

A thermoformed container was obtained by thermoforming the obtained multilayer film using a thermoforming machine (R530 manufactured by Multi-Back Co., Ltd.). In other words, the multilayer film was heated at a mold temperature of 100 ° C. for 2 seconds, and compressed air (atmospheric pressure 5 kgf / cm ² ) was used for the mold shape (vertical: 130 mm, width: 110 mm, depth: 60 mm rectangular parallelepiped shape). Molded to obtain a thermoformed container. When the appearance of the obtained thermoformed container was visually observed, there was no unevenness and local uneven thickness, and the film was stretched uniformly and the appearance was good.

Example 4
The pellet obtained in Example 2 was used as a resin composition layer, a linear low density polyethylene (LLDPE) resin (“Mirason 102” manufactured by Mitsui Chemicals, Inc.) was used as the outermost layer, and “Bondyne TX8030” manufactured by Sumitomo Chemical Co., Ltd. ") Was used as an adhesive (AD) layer to produce a 5-layer coextrusion direct blow molded container. The molding conditions are as follows.
Molding machine: 4 types 7-layer direct blow molding machine manufactured by Suzuki Iron Works Resin composition extrusion temperature: 210 ° C
Low density polyethylene extrusion temperature: 195 ° C
Adhesive resin extrusion temperature: 195 ° C
Mold temperature: 15 ℃
Bottle capacity: 1000ml
Layer structure: LLDPE / AD / resin composition / AD / LLDPE
= 340/20/40/20/340 (μm)

  When the obtained blow-molded container was visually observed, no delamination, haze, streak, bubbles or gel was observed, and the product had a good appearance.

Example 5
Using the resin composition pellets obtained in Example 2 and polyethylene terephthalate (PET) “PET9921W” manufactured by VORIDIAN, co-injected continuously for 24 hours using a KORTEC / HUSKY co-injection molding machine (four SL160 molds). Molding was performed to form a bottomed parison having two types and three layers of PET / resin composition / PET. At this time, the PET side injection machine temperature is 280 ° C., the resin composition side injection machine temperature is 210 ° C., the hot runner block part where the PET and the resin composition merge is 270 ° C., the injection mold core temperature is 10 ° C., the injection The mold cavity temperature was 10 ° C. Further, the injection speed and the injection amount were adjusted so that the thickness ratio of the PES layer and the resin composition layer in the container was 95/5. When this parison was visually observed, no coloring or streak was observed.

  Then, using a stretch blow molding machine made by CRUPP CORPLAST MASCHINENBAU (one LB01 type 530 mL), the surface temperature of the bottomed parison (immediately after 24 hours of continuous operation) is heated to 105 ° C., stretch blow molding is performed, A two-kind three-layer co-injection stretch blow molded container was obtained. The thickness constitution of the container was (inner) PET / resin composition / PET (outer) = 140/25/180 (μm). The outer appearance of the obtained container was visually observed, but no delamination, haze, or irregularities were observed, and neither coloring nor streak was observed.

Claims (27)

The content of the alkali metal salt (A) is 0.1 to 20 μmol / g in terms of alkali metal, the content of the carboxylic acid or its salt (C) is 2 μmol / g or less in terms of carboxylic acid root, and ethylene-vinyl ethylene content of alcohol copolymer resin is 5 to 60 mol%, ethylene - saponification degree of vinyl alcohol copolymer resin Ri 80 to 99 mol% der, and at least the alkali metal salt (a) An ethylene-vinyl alcohol copolymer resin composition (F), part of which is carbonate or hydrogen carbonate .   The ethylene-vinyl alcohol copolymer resin composition (F) according to claim 1, wherein the ethylene content is 47 to 60 mol%.   The ethylene-vinyl alcohol copolymer resin composition (F) according to claim 1 or 2, wherein the alkali metal salt (A) is a potassium salt.   The ethylene-vinyl alcohol copolymer resin composition (F) according to any one of claims 1 to 3, wherein the content of the alkaline earth metal salt (E) is 0.25 µmol / g or less in terms of alkaline earth metal.   A molded article comprising the ethylene-vinyl alcohol copolymer resin composition (F) according to any one of claims 1 to 4.   The film which consists of an ethylene-vinyl alcohol copolymer resin composition (F) in any one of Claims 1-4.   A blow molded container comprising the ethylene-vinyl alcohol copolymer resin composition (F) according to any one of claims 1 to 4.   A thermoformed container comprising the ethylene-vinyl alcohol copolymer resin composition (F) according to any one of claims 1 to 4.   The multilayer structure containing at least 1 layer which consists of an ethylene-vinyl alcohol copolymer resin composition (F) in any one of Claims 1-4. The content of the alkali metal salt (A) is 0.1 to 20 μmol / g in terms of alkali metal, the content of the carboxylic acid or its salt (C) is 2 μmol / g or less in terms of carboxylic acid root, and ethylene-vinyl ethylene content of alcohol copolymer resin is 5 to 60 mol%, ethylene - saponification degree of vinyl alcohol copolymer resin Ri 80 to 99 mol% der, and at least the alkali metal salt (a) 1 to 99% by weight of an ethylene-vinyl alcohol copolymer resin composition (F) that is partly carbonate or bicarbonate , ethylene content is 5 to 60 mol%, and saponification degree is 99.2. A resin composition comprising 1 to 99% by weight of an ethylene-vinyl alcohol copolymer resin that is ˜100 mol% . A molded article comprising the resin composition according to claim 10 . A film comprising the resin composition according to claim 10 . A blow molded container comprising the resin composition according to claim 10 . A thermoformed container comprising the resin composition according to claim 10 . A multilayer structure comprising at least one layer comprising the resin composition according to claim 10 . An ethylene-vinyl alcohol copolymer resin having an ethylene content of 5 to 60 mol% and a saponification degree of 80 to 99 mol% is added to an aqueous solution containing an alkali metal carbonate or hydrogen carbonate and carbon dioxide gas. The manufacturing method of the ethylene-vinyl alcohol copolymer resin composition (F) made to contact. The method for producing an ethylene-vinyl alcohol copolymer resin composition (F) according to claim 16 , wherein the ethylene content is 47 to 60 mol%. The manufacturing method of the molding which melt-molds the ethylene-vinyl alcohol copolymer resin composition (F) manufactured by the method of Claim 16 or 17 . The manufacturing method of the film which melt-molds the ethylene-vinyl alcohol copolymer resin composition (F) manufactured by the method of Claim 16 or 17 . The manufacturing method of a thermoformed container using the ethylene-vinyl alcohol copolymer resin composition (F) manufactured by the method of Claim 16 or 17 . The manufacturing method of the multilayer structure which laminates | stacks the ethylene-vinyl alcohol copolymer resin composition (F) manufactured by the method of Claim 16 or 17, and a thermoplastic resin. An ethylene-vinyl alcohol copolymer resin having an ethylene content of 5 to 60 mol% and a saponification degree of 80 to 99 mol% is added to an aqueous solution containing an alkali metal carbonate or hydrogen carbonate and carbon dioxide gas. A resin composition characterized by being melt-kneaded with an ethylene-vinyl alcohol copolymer resin having an ethylene content of 5 to 60 mol% and a saponification degree of 99.2 to 100 mol% after contact. Manufacturing method. The manufacturing method of the molding which melt-molds the resin composition manufactured by the method of Claim 22 . The manufacturing method of the film which melt-molds the resin composition manufactured by the method of Claim 22 . The manufacturing method of the blow molding container using the resin composition manufactured by the method of Claim 22 . The manufacturing method of the thermoformed container using the resin composition manufactured by the method of Claim 22 . The manufacturing method of the multilayered structure which laminates | stacks the resin composition manufactured by the method of Claim 22 , and a thermoplastic resin.