JP2003020023A - Plastic multi-layer container - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a multi-layer container in which carbonated gas is prevented from being permeated, a thermoplastic resin layer is placed between an oxygen absorbing layer and a non-organic film layer while residual oxygen in the resin is being caught, the non organic film layer is not influenced by deterioration caused by catching oxygen of the oxygen absorbing layer, and a fragile characteristic in the non-organic film layer is restricted. SOLUTION: A plastic multi-layer container is constituted by an inner layer 2 made of thermoplastic resin and an outer layer 4. An oxygen absorbing layer 3 is placed between the inner layer 2 and the outer layer 4, and the surfaces of the inner layer 2 and the outer layer 4 or the surface of the inner layer or the outer layer is provided with a non organic film layer 5.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a plastic multi-layer container, and more particularly to a plastic multi-layer container excellent in carbon dioxide gas barrier property and oxygen scavenging property.

[0002]

2. Description of the Related Art Polyethylene terephthalate (PET)
Stretching container consisting of etc. is excellent in transparency, impact resistance (fall resistance), lightness, hygiene, moderate gas barrier properties such as oxygen and carbon dioxide, pressure resistance, etc., and beer, cola, cider It is widely used as a packaging container for beverages such as carbonated drinks, carbonated drinks containing fruit juice, fruit juice drinks, teas, coffee and the like. However, in a completely sealed container such as a glass bottle or a metal can, the gas permeability is equal to zero, but the stretched polyester container has a slight permeability to oxygen and carbon dioxide gas. Therefore, it is inferior in filling and storability of food to cans and glass bottles.

In particular, when filled and sealed in a stretched polyester bottle for carbonated beverages such as beer, cola and cider (pressure resistant polyester bottle) or a stretched polyester container for carbonated beverages containing fruit juice (heat resistant pressure polyester bottle), the beverage is Due to the outflow of carbon dioxide in the atmosphere and the residual oxygen in the resin, these beverages have a clear shelf life,
Alternatively, the storage period will be limited.

In Japanese Patent No. 2991437, etc., the container has a multilayer structure in which an inner and outer layers of polyester and an oxygen absorbing layer are provided between the inner and outer layers, and oxygen is trapped to prevent alteration of the contents. Is proposed.

Further, Japanese Patent No. 2526766, Japanese Unexamined Patent Publication No. 8-53116, and the like propose that a silicon oxide or carbon film is formed on a plastic container to provide a gas barrier property.

Further, Japanese Patent Laid-Open No. 7-101468,
Japanese Patent Laid-Open No. 2001-2135 proposes that an inorganic film layer is provided on an oxygen barrier resin composition layer composed of a thermoplastic resin and an oxidation catalyst.

[0007]

However, these proposals are limited to the application of oxygen trapping and gas barrier properties,
This is not a container that has solved the problem of providing an inorganic film layer on the oxygen absorption layer. That is, the oxygen absorption layer consisting of a thermoplastic resin and an oxidation catalyst, when oxygen is captured, the resin deteriorates and causes cracks, and when an inorganic film layer is provided on the oxygen absorption layer, the cracks are transmitted to the inorganic film layer. However, the gas barrier property may be deteriorated. In addition, the surface of the oxygen absorbing layer is generally a rough surface, and it is difficult to obtain smoothness or uniformity of the inorganic film layer provided on the oxygen absorbing layer, and the inorganic film layer is likely to be missing. Further, the oxygen absorption layer and the inorganic film layer are brittle, and cracks and peeling easily occur due to deformation of the container.

Therefore, the object of the present invention is to capture the residual oxygen in the resin while preventing the permeation of carbon dioxide gas to the outside, and to prevent the cracks caused by the deterioration of the resin due to the oxygen capture of the oxygen absorbing layer. A multi-layer plastic container capable of preventing transmission to an inorganic membrane layer and lack of the inorganic membrane layer, and improving the brittleness of the oxygen absorbing layer and the inorganic membrane layer to prevent cracking or peeling due to deformation of the container. Is to provide.

[0009]

According to the present invention, an inner layer and an outer layer made of a thermoplastic resin and an oxygen absorbing layer between the inner layer and the outer layer are provided, and an inorganic film layer is provided on the surface of the inner layer and / or the outer layer. There is provided a plastic multi-layer container provided with. In these plastic multi-layer containers, an inorganic film layer such as a silicon oxide film or a carbon film is provided on the surface of the inner layer and / or the outer layer of the plastic container, and an oxygen absorption layer is provided as an intermediate layer, so that the carbon dioxide gas It is possible to highly prevent the permeation and capture the residual oxygen in the resin. Further, since the thermoplastic resin layer is present between the oxygen absorption layer and the inorganic film layer, even in the presence of the oxygen absorption layer and the inorganic film layer, the cracking of the inorganic absorption layer due to the deterioration of the oxygen absorption layer It is possible to prevent transmission and prevent the inorganic membrane layer from being lost. Further, it is possible to improve the brittleness of the oxygen absorbing layer and the inorganic membrane layer and prevent cracks and peeling due to deformation of the container.

In the plastic multilayer container of the present invention, the relationship between the flexural modulus ε1 of the thermoplastic resin layer of the inner layer and / or the outer layer provided with the inorganic membrane layer and the flexural modulus ε2 of the thermoplastic resin of the oxygen absorbing layer. Is defined as ε1 <ε2, in which the hard oxygen absorbing layer is held by the soft inner layer and / or outer layer, and the inner layer and / or outer layer is further coated with an inorganic film, so that the inorganic film is destroyed during transportation or dropping. It is preferable in terms of preventing peeling and peeling between layers.

In the plastic multilayer container of the present invention, the surface roughness (JIS B0601) of the surface of the inner layer and / or the outer layer on which the inorganic film layer is formed is 25 nm.
The following ten-point average roughness (Rz) and center line average roughness (Ra) of 10 nm or less are preferable from the viewpoint of forming a dense inorganic film. Surface ten-point average roughness (Rz) and center line average roughness (R) of the thermoplastic resin layer on which the inorganic film layer is formed.
When a) exceeds the above numerical values, it becomes difficult to form an excellent gas barrier film.

In such a plastic multi-layer container,
The inorganic film layer is preferably a silicon oxide film. Among the inorganic film layers, the silicon oxide film is particularly transparent, impact resistant, and
It has excellent flexibility, and has excellent commercial value and recyclability when used as a plastic multi-layer container.

The thickness of the silicon oxide film layer is preferably 2 to 500 nm, because it peels or cracks due to deformation of the container unless it is thin enough to have flexibility. Particularly preferably, it is in the range of 100 nm.

The oxygen absorbing layer preferably contains an oxidizable organic component and a transition metal catalyst. By including the oxidizable organic component and the transition metal catalyst, oxygen in the resin in the inner and outer layers can be efficiently captured.

The oxidizable organic component is preferably a gas barrier resin. The gas barrier resin is oxidized by the transition metal catalyst to have an oxygen scavenging ability. Therefore, by using a gas barrier resin for the oxygen absorbing layer, it is possible to capture oxygen in the resin of the inner and outer layers while further preventing the permeation of carbon dioxide gas in combination with the presence of the inorganic membrane layer.

Further, the gas barrier resin is preferably a xylylene group-containing polyamide. Xylylene group-containing polyamide, in particular, compared to all-aliphatic polyamide,
The gas permeability is small, which is preferable from the viewpoint of gas barrier properties. Therefore, by using the xylylene group-containing polyamide for the oxygen absorbing layer, combined with the presence of the inorganic membrane layer, while further preventing the permeation of carbon dioxide gas, it is possible to capture oxygen in the resin of the inner layer and the outer layer. it can.

Furthermore, it is preferable that the oxygen absorption layer contains a gas barrier resin that does not substantially oxidize, an oxidizable organic component and a transition metal catalyst. Oxygen absorbing layer, by containing an oxidizable organic component in addition to the gas barrier resin and the transition metal catalyst, deterioration due to oxygen trapping of the gas barrier resin layer is prevented, and in combination with the presence of the inorganic film layer, Oxygen in the resin in the inner layer and the resin in the outer layer can be captured for a long period of time while further preventing the permeation of carbon dioxide gas.

The transition metal catalyst is preferably a cobalt salt. Cobalt salt is preferable from the viewpoint of oxygen absorption, and this catalyst has an advantage that it is excellent in dispersibility in a resin and that it is not colored enough to make the container unsightly.

Further, the plastic multilayer container of the present invention is
It is preferable that the inner layer and the outer layer are polyester resins, and the plastic multilayer container is biaxially stretch blow molded.
A polyester multi-layer container having excellent gas barrier and rigidity can be obtained by subjecting the polyester resin to a preform by injection molding and then biaxially stretch blow molding. As a result, by composing the inner layer and outer layer of the multi-layer plastic container with the biaxially stretched thermoplastic polyester layer, the permeation of the carbon dioxide gas is further ensured in combination with the inorganic membrane layer on the surface of the inner layer and / or the outer layer. In addition to the above, since the rigidity of the container is imparted, the influence of the oxygen absorption layer and the inorganic film layer due to the deformation of the container is mitigated, and the plastic multi-layer container in which brittleness is suppressed can be obtained.

[0020]

BEST MODE FOR CARRYING OUT THE INVENTION The plastic multilayer container of the present invention will be described in more detail below. [Structure of Plastic Multilayer Container] The multilayer structure of the plastic multilayer container of the present invention will be described. FIG. 1 shows a multilayer structure in the plastic multilayer container of the present invention, and is an enlarged cross-sectional view of a wall in a main part of the plastic multilayer container. The plastic multilayer container 1 of the present invention comprises an inner layer 2 made of a polyester resin, an outer layer 3 made of polyester, and an oxygen absorption layer 4 located between them, and further, an inorganic film layer 5 is provided on the surface of the outer layer 3. Has been.

In the plastic multi-layer container 1 of the present invention, in addition to the inner layer 2, the outer layer 3 and the oxygen absorbing layer 4, other olefin resins, gas barrier resins, cyclic olefin copolymers, recycled polyester, etc. It can include layers. Examples of the olefin resin include low density polyethylene (LDPE) and medium density polyethylene (MDP).
E), polyethylene (PE) such as high-density polyethylene (HDPE), linear low-density polyethylene (LLDPE), and linear ultra-low-density polyethylene (LVLDPE), polypropylene (PP), ethylene-propylene copolymer, polybutene-1. , Ethylene-butene-1 copolymer, propylene-butene-1 copolymer, ethylene-propylene-butene-1 copolymer, ethylene-vinyl acetate copolymer, ion-crosslinked olefin copolymer (ionomer) or these Blends and the like can be mentioned.

The following is an example of the multi-layer structure of the plastic multi-layer container of the present invention. Two-kind three-layer structure: PET / MXD6 / PET / inorganic film layer Two-kind five-layer structure: PET / MXD6 / PET / MXD6 /
PET / inorganic film layer, three kinds, five layers structure: PET / AD / MXD6 / AD / PET
/ Inorganic film layer (PET: polyethylene terephthalate, MXD6: polyamide resin, AD: adhesive)

FIG. 2 shows another example of the multi-layer structure in the plastic multi-layer container of the present invention. The plastic multi-layer container 1 includes an inner layer 2 made of a polyester resin, an outer layer 3 made of a polyester resin, and a space between them. And an inorganic film layer 5 is provided on the surface of the inner layer 2.

FIG. 3 shows still another example of the multilayer structure of the plastic multi-layer container of the present invention. The plastic multi-layer container 1 includes an inner layer 2 made of a polyester resin, an outer layer 3 made of a polyester resin, and these layers. An oxygen absorption layer 4 located between the inner layer 2 and
The inorganic film layer 5 is provided on the surface of the outer layer 3.

An adhesive resin may be interposed between the resin layers, if necessary. Examples of such an adhesive resin include carboxylic acid, carboxylic anhydride, carboxylic acid salt, carboxylic acid amide, and carboxylic acid ester. A carbonyl (-CO-) group based on the main chain or side chain, 1 to 700 milliequivalent (meq) / 100 g resin, especially 10 to
A thermoplastic resin contained at a concentration of 500 meq / 100 g resin can be mentioned. Suitable examples of adhesive resins include ethylene-acrylic acid copolymers, ion-crosslinked olefin copolymers, maleic anhydride grafted polyethylenes, maleic anhydride grafted polypropylenes, acrylic acid grafted polyolefins, ethylene-vinyl acetate copolymers, copolymers. One or a combination of two or more of polymerized polyester, copolyamide and the like. These resins are useful for lamination by coextrusion or sandwich lamination and the like.

[Thickness] 1. Oxygen Absorbing Layer In the plastic multilayer container of the present invention, the oxygen absorbing layer 3
The thickness of is not particularly limited, but is generally 3 to 100 μm,
It is particularly preferably in the range of 5 to 50 μm. That is, if the thickness of the oxygen absorption layer is thinner than a certain range, the oxygen absorption performance is poor, and even if it is thicker than a certain range, there is no particular advantage in terms of oxygen absorption, and the amount of resin is increased. This is because it is disadvantageous in terms of properties and container characteristics such as flexibility and deterioration of flexibility of the material.

2. Inorganic membrane layer In the plastic multilayer container of the present invention, the thickness of the inorganic membrane layer is not particularly limited, but is generally 2 to 500 nm, particularly 1
The carbon dioxide gas of the film is in the range of 0 to 100 nm,
It is preferable in terms of impact resistance and flexibility. The thickness of the inorganic film layer is 2n
When it is less than m, the barrier property against carbon dioxide gas is lowered,
On the other hand, when it is 500 nm or more, impact resistance and flexibility are deteriorated.

3. Overall thickness of plastic multi-layer container In the plastic multi-layer container 1 of the present invention, the total thickness of the layers varies depending on the application, but is generally 30 to 700.
0 μm, especially 50 to 5000 μm, while the thickness of the intermediate layer of the oxygen absorbing layer is 0.5 to 9 of the total thickness.
A thickness of 5%, especially 1 to 50% is suitable.

[Manufacturing Method of Plastic Multilayer Container] The manufacturing method when the plastic multilayer container is formed into a biaxially stretched bottle will be described below, but the present invention is not limited to this form. 1. Production of multi-layer preform The production of multi-layer preform, using a conventionally known co-injection molding machine, the inner layer and the outer layer is a polyester resin, insert one or more oxygen absorption layer between the inner layer and outer layer, injection It is possible to manufacture a multi-layer preform having a bottom portion and an opening portion corresponding to the shape of the preform mold for use.

As one of the methods, a co-injection molding machine equipped with two or more injection machines and a co-injection mold are used, the inner layer and the outer layer are made of polyester resin, and one layer is formed in the middle so as to be covered with the inner layer and the outer layer. Or insert more oxygen absorption layer,
It is also possible to manufacture a multi-layer preform having a bottom and an opening corresponding to the shape of the injection preform mold.

Further, a multistage injection machine having three or more injection machines is used to first form a primary inner layer preform, then transfer it to a secondary mold and inject an intermediate layer, and further a third mold. It is also possible to inject the outer layer with, and successively transfer the multi-stage mold to manufacture a multi-layer preform.

Further, a first-stage inner layer preform is first injection-molded by a multi-stage injection machine, then the preform is transferred to a second mold to inject an oxygen absorbing layer, and the preform is third-staged. It is also possible to transfer to a mold and inject the outer layer, and then use a multi-stage mold to manufacture a multi-layer preform.

As another method, it can be manufactured by compression molding. In this case, the oxygen absorbing layer resin is provided in the melted mass resin forming the inner and outer layers, and the melted mass is supplied to the female mold without substantially lowering the temperature and is compression-molded by the male mold.

In order to impart heat and pressure resistance to the mouth and neck of the preform thus obtained, at the preform stage,
The mouth and neck may be crystallized and whitened by heat treatment. Further, the mouth-and-neck portion of the unstretched portion may be crystallized and whitened after completion of molding by stretch blow described later. If necessary, an adhesive layer may be provided between the layers of the multilayer preform.

2. Production of blow-molded body Next, the multilayer preform is biaxially stretch blow-molded,
The methods are roughly classified into a hot parison method and a cold parison method. In the former hot parison method, the preform is biaxially stretch blow molded in a softened state without being completely cooled. On the other hand, in the latter cold parison method, the preform is formed as a supercooled bottomed preform that is much smaller than the dimensions of the final shape and the polyester is amorphous, and this preform is preheated to its stretching temperature. In the blow molding die, stretch drawing is carried out in the axial direction and blow drawing is carried out in the circumferential direction. In any method, this multilayer preform is heated to a glass transition temperature (Tg) or higher, for example, at a temperature of 85 to 120 ° C., then biaxially stretch blow-molded in a mold, and stretched in a longitudinal direction with a stretching rod. In addition, it is stretched in the transverse direction by blow air. The draw ratio of the final blow-molded product is preferably 1.2 to 6 times in the longitudinal direction and 1.2 to 4.5 times in the lateral direction.

3. Manufacture of another blow-molded body As another method of manufacturing a blow-molded body, a multilayer preform is used, and a patent No. 2917851 relating to the present applicant.
As described in Japanese Patent Publication (Kokai) No. 2004-242242, the multilayer preform is made into a primary blow-molded product having a size larger than the final blow-molded product using a primary biaxially stretched blow mold, and then this primary blow-molded product is heat-shrinkable. After that, a two-stage blow molding may be adopted in which biaxial stretch blow molding is performed using a secondary mold to obtain a final blow molded body. According to this method for producing a blow-molded product, the bottom portion of the blow-molded product can be sufficiently stretched and thinned, and a blow-molded product having excellent impact resistance can be obtained.

4. Heat Treatment (Heat Set) If necessary, the outer side of the vessel wall of the blow-molded body may be brought into contact with the inner surface of the mold for a predetermined time during the biaxial stretching blow to perform heat treatment to impart heat pressure resistance or heat resistance.

[Inner Layer and Outer Layer] As the thermoplastic resin used in the inner layer and outer layer of the present invention, an olefin resin, a polyester resin or the like is used depending on the application. As the olefin resin, low density, medium density or high density polyethylene, linear low density polyethylene, ionomer, homopolypropylene, block copolymer or random copolymer type polypropylene, linear low density polyethylene, ethylene-propylene copolymer Coalesce, polybutene-1, ethylene-butene-1 copolymer, propylene-butene-1 copolymer, ethylene-propylene-butene-1 copolymer, polymethyl-pentene-1, cyclic olefin-based polymer, cyclic olefin-based A copolymer (COC) or the like is used.

However, the thermoplastic resin used for the inner layer and the outer layer of the present invention is preferably a biaxially stretch blow-moldable polyester resin, and any polyester resin can be used, but polyethylene terephthalate, Thermoplastic polyester such as polybutylene terephthalate, polyethylene naphthalate, polycarbonate, polyarylate, or copolymers thereof,
Blends of these resins or other resins are preferably used, and particularly ethylene terephthalate thermoplastic polyesters such as polyethylene terephthalate are preferably used.

The ethylene terephthalate type thermoplastic polyester used in the inner layer and the outer layer is a polymer in which ethylene terephthalate units account for most of the ester repeating units, generally 70 mol% or more, and have a glass transition point (Tg) of 50.
Those having a melting point (Tm) in the range of to 90 ° C and a melting point (Tm) of 200 to 275 ° C are preferable. Polyethylene terephthalate as an ethylene terephthalate thermoplastic polyester is particularly excellent in terms of pressure resistance, heat resistance, heat resistance and pressure resistance, but in addition to ethylene terephthalate units, dibasic acids such as isophthalic acid and naphthalene dicarboxylic acid and diols such as propylene glycol. Copolymerized polyesters containing small amounts of ester units consisting of can also be used.

Further, as the inner layer 2 and the outer layer 4, a degradable thermoplastic resin which disappears in a natural environment in consideration of disposal after use can also be used. Examples of the degradable thermoplastic resin include a photodegradable thermoplastic resin in which the molecular chain of the polymer is cleaved by ultraviolet rays, and a biodegradable thermoplastic resin that is disintegrated by the action of an enzyme that bacteria and fungi release outside the body. To be

However, the photodegradable thermoplastic resin is
A biodegradable thermoplastic resin is preferable as the degradable thermoplastic resin because the effect cannot be expected in soil burial treatment and there is a risk of environmental pollution due to decomposition products. Examples of the biodegradable thermoplastic resin include aliphatic polyesters such as polyhydroxybutyrate (PHA), a random copolymer of 3-hydroxybutyrate (3HB) and 3-hydroxyvalerate (3HV), and poly (ε-caprolactone). )
(PCL), polybutylene succinate (PBS), polybutylene succinate adipate (PBAS), polylactic acid (PLLA), and the like.

Various additives such as colorants, ultraviolet absorbers, release agents, lubricants, nucleating agents and antioxidants are added to the above-mentioned polyolefin resin or polyester resin within the range of not impairing the quality of molded products. , An antistatic agent and the like may be added.

[Oxygen Absorption Layer] The oxygen absorption layer 3 of the present invention comprises
Any substance can be used as long as it absorbs oxygen and prevents permeation of oxygen, but it is a combination of an oxidizable organic component and a transition metal catalyst, or a gas barrier resin that does not substantially oxidize, and an oxidizable Combinations of organic components and transition metal catalysts are preferably used.

A gas barrier resin that does not substantially oxidize,
In the combination of the oxidizable organic component and the transition metal catalyst, the oxidizable organic component has a faster oxidation reaction than the gas barrier resin, and the oxidizable organic component is exclusively oxidized and absorbs oxygen. Therefore, the gas barrier resin does not substantially oxidize and does not deteriorate in oxygen barrier property due to oxidative deterioration, so that it can exhibit an oxygen absorbing function for a long time. For this reason, this combination is particularly preferred. That is, in this combination, it is considered that the oxygen barrier property retention by the gas barrier resin and the oxygen absorption property development by the oxidizable organic component are performed in a function-separated manner. Hereinafter, each component will be described in detail.

1. Oxidizable Organic Component The oxidizable organic component includes a gas barrier resin and polyene. (1) Gas Barrier Resin As an example of the gas barrier resin, ethylene-vinyl alcohol copolymer (EVOH) can be mentioned. For example, the ethylene content is 20 to 60 mol%, particularly 25 to
A saponification product of a copolymer obtained by saponifying an ethylene-vinyl acetate copolymer of 50 mol% so that the saponification degree is 96 mol% or more, particularly 99 mol% or more is used. The saponified ethylene vinyl alcohol copolymer should have a molecular weight sufficient to form a film, and is generally 0.01 dl measured at 30 ° C. in a mixed solvent of 85:15 by weight of phenol: water. It is desirable to have a viscosity of not less than / g, especially not less than 0.05 dl / g.

Further, as other gas barrier resin,
Cyclic olefin copolymer (COC), especially copolymer of ethylene and cyclic olefin, especially AP manufactured by Mitsui Chemicals, Inc.
EL or the like can be used.

Further, as another gas barrier resin, a polyamide resin can be mentioned. Examples of the polyamide resin include (a) an aliphatic, alicyclic or semiaromatic polyamide derived from a dicarboxylic acid component and a diamine component, (b) a polyamide derived from an aminocarboxylic acid or a lactam thereof, or a product thereof. Examples include copolyamides or blends thereof.

Examples of the dicarboxylic acid component include succinic acid, adipic acid, sebacic acid, decanedicarboxylic acid,
Examples thereof include an aliphatic dicarboxylic acid having 4 to 15 carbon atoms such as undecanedicarboxylic acid or dodecanedicarboxylic acid; and aromatic dicarboxylic acids such as terephthalic acid and isophthalic acid.

As the diamine component, 1,6-diaminohexane, 1,8-diaminooctane, 1,10
-Diaminodecane, 1,12-diaminododecane, and other linear or branched alkylenediamines having 4 to 25 carbon atoms, particularly 6 to 18, bis (aminomethyl) cyclohexane, bis (4-aminocyclohexyl) methane, 4 ，
4'-diamino-3,3'-dimethyldicyclohexylmethane, especially bis (4-aminocyclohexyl) methane, 1,3-bis (aminocyclohexyl) methane,
Examples thereof include alicyclic diamines such as 1,3-bis (aminomethyl) cyclohexane, and araliphatic diamines such as m-xylylenediamine and / or p-xylylenediamine.

As the aminocarboxylic acid component, an aliphatic aminocarboxylic acid such as ω-aminocaproic acid, ω-aminooctanoic acid, ω-aminoundecanoic acid, ω-aminododecanoic acid or, for example, para-aminomethylbenzoic acid or para-amino acid. Examples thereof include araliphatic aminocarboxylic acids such as aminophenylacetic acid.

Among these polyamides, a xylylene group-containing polyamide is preferable, and specifically, polymetaxylylene adipamide, polymetaxylylene sebacamide, polymetaxylylene sveramide, polyparaxylylene pimeramide, Homopolymers such as polymetaxylylene azelamide, and metaxylylene / paraxylylene adipamide copolymers, metaxylylene / paraxylylene pimeramide copolymers, metaxylylene / paraxylylene sebacamide copolymers, metaxylylene / Copolymers such as paraxylyleneazeramide copolymers, or components of homopolymers or copolymers thereof with aliphatic diamines such as hexamethylenediamine, alicyclic diamines such as piperazine, and para-bis (2amino). Aromatic diamines such as ethyl) benzene, aromatic diamines such as terephthalic acid Rubonic acid, lactams such as ε-caprolactam, ω-aminocarboxylic acids such as 7-aminoheptanic acid, and copolymers obtained by copolymerizing aromatic aminocarboxylic acids such as para-aminomethylbenzoic acid. m
A polyamide obtained from a diamine component containing xylylenediamine and / or p-xylylenediamine as a main component and an aliphatic dicarboxylic acid and / or an aromatic dicarboxylic acid can be particularly preferably used. These xylylene group-containing polyamides are preferable because they have an excellent oxygen barrier property as compared with other polyamide resins.

The polyamide resin used in the present invention is 40e.
It is preferable to have a terminal amino group concentration of q / 10 ⁶ g or more. When the terminal amino group concentration is below the above range, the polyamide resin is deteriorated, which is not preferable. The polyamide resin having a terminal amino group concentration within the above range can be selected from commercially available polyamide resins and used. Due to the mechanical properties of the container and the ease of processing, these polyamide resins have relative viscosities (ηrel) measured in 98% sulfuric acid at a concentration of 1.0 g / dl and a temperature of 20 ° C. of 1.3 to 4. It is desirable that it is within the range of 2, especially 1.5 to 3.8.

(2) Polyene The oxidizable organic component used in the present invention is preferably a polymer derived from polyene. As such a polyene, a resin containing a unit derived from a polyene having 4 to 20 carbon atoms, a chain or cyclic conjugated or non-conjugated polyene is preferably used. Examples of these monomers include conjugated dienes such as butadiene and isoprene; 1,4-hexadiene, 3-methyl-1,4-hexadiene, 4-methyl-1,4-hexadiene, 5-methyl-1, 4-hexadiene, 4,5-dimethyl-1,4-hexadiene,
Chain-like non-conjugated dienes such as 7-methyl-1,6-octadiene; methyltetrahydroindene, 5-ethylidene-2
-Norbornene, 5-methylene-2-norbornene, 5
-Cyclic non-conjugated dienes such as isopropylidene-2-norbornene, 5-vinylidene-2-norbornene, 6-chloromethyl-5-isopropenyl-2-norbornene, dicyclopentadiene; 2,3-diisopropylidene-5
-Norbornene, 2-ethylidene-3-isopropylidene-5-norbornene, trienes such as 2-propenyl-2,2-norbornadiene, chloroprene and the like can be mentioned.

These polyenes are incorporated in the form of a homopolymer, a random copolymer, a block copolymer, etc., alone or in combination of two or more kinds, or in combination with other monomers. As the monomer used in combination with the polyene, α-olefin having 2 to 20 carbon atoms, for example, ethylene, propylene, 1-butene, 4-methyl-1-pentene, 1-hexene, 1-heptene, 1 -Kuten, 1-
Nonene, 1-decene, 1-undecene, 1-dodecene,
1-tridecene, 1-tetradecene, 1-pentadecene, 1-hexadecene, 1-heptadecene, 1-nonadecene, 1-eicosene, 9-methyl-1-decene, 11
-Methyl-1-dodecene and 12-ethyl-1-tetradecene are mentioned, and other monomers such as styrene, vinyltoluene, acrylonitrile, methacrylonitrile, vinyl acetate, methyl methacrylate, ethyl acrylate and the like can also be used.

As the polyene polymer, specifically,
Polybutadiene (BR), polyisoprene (IR), butyl rubber (IIB), natural rubber, nitrile-butadiene rubber (NBR), styrene-butadiene rubber (SB
R), chloroprene rubber (CR), ethylene-propylene-diene rubber (EPDM), and the like, but not limited to these examples. The carbon-carbon double bond in the polymer is not particularly limited and may be present in the main chain in the form of vinylene group or in the side chain in the form of vinyl group. It is preferable that these polyene-based polymers have carboxylic acid groups, carboxylic acid anhydride groups, and hydroxyl groups introduced therein. Examples of the monomer used for introducing these functional groups include the ethylenically unsaturated monomers having the above functional groups. As these monomers, it is desirable to use unsaturated carboxylic acids or derivatives thereof, and specifically, acrylic acid, methacrylic acid, maleic acid, fumaric acid, itaconic acid, citraconic acid, tetrahydrophthalic acid, etc. Unsaturated carboxylic acids such as α, β-unsaturated carboxylic acid, bicyclo [2,2,1] hept-2-ene-5,6-dicarboxylic acid, maleic anhydride, itaconic anhydride, citraconic anhydride, tetrahydro Α, β unsaturated carboxylic acid anhydrides such as phthalic anhydride, bicyclo [2,2,2]
1] An unsaturated carboxylic acid anhydride such as hept-2-ene-5,6-dicarboxylic acid anhydride.

The acid modification of the polyene polymer is carried out by using a resin having a carbon-carbon double bond as a base polymer and graft-copolymerizing an unsaturated carboxylic acid or its derivative with this base polymer by a means known per se. Although it is produced, it can also be produced by randomly copolymerizing the above-mentioned polyene and an unsaturated carboxylic acid or a derivative thereof. Particularly preferred modified polyene-based polymer is
The unsaturated carboxylic acid or its derivative is contained in an amount of 0.01 to 10 mol%. When the content of the unsaturated carboxylic acid or its derivative is within the above range, the dispersion of the acid-modified polyene-based polymer in the polyamide resin becomes good, and
Oxygen is absorbed smoothly. Also, a hydroxyl group-modified polyene polymer having a hydroxyl group at the terminal can be favorably used. The polyene polymer used in the present invention has a temperature of 40 ° C.
It is preferable that the viscosity in the range of 1 to 200 Pa · s is in view of the workability of the oxygen absorbing layer.

2. Transition Metal Catalyst The transition metal catalyst used in the present invention is preferably a Group VIII metal component such as iron, cobalt and nickel, but other Group I metals such as copper and silver: tin, titanium and zirconium. Group IV metals such as V group, vanadium group V, chromium such as VI group, and manganese such as VII metal component. Among these metal components, the cobalt component has a high oxygen absorption rate and is particularly preferable.

The transition metal-based catalyst is generally used in the form of a low-valent inorganic or organic acid salt or complex salt of the above transition metal. As the inorganic acid salt, halides such as chlorides, sulfur oxyacid salts such as sulfates, nitrogen oxyacid salts such as nitrates,
Examples thereof include phosphorus oxyacid salts such as phosphates, silicates and the like.

On the other hand, as the organic acid salt, a carboxylic acid salt,
Examples thereof include sulfonates and phosphonates, and carboxylates are suitable for the purpose of the present invention, and specific examples thereof include acetic acid, propionic acid, isopropionic acid, butanoic acid, isobutanoic acid, pentanoic acid, Isopentanoic acid, hexanoic acid, heptanoic acid, isoheptanoic acid, octanoic acid, 2
-Ethylhexanoic acid, nonanoic acid, 3,5,5-trimethylhexanoic acid, decanoic acid, neodecanoic acid, undecanoic acid, lauric acid, myristic acid, palmitic acid, margaric acid, stearic acid, arachidic acid, lindelic acid, Examples thereof include transition metal salts such as duzic acid, petroselinic acid, oleic acid, linoleic acid, linolenic acid, arachidonic acid, formic acid, oxalic acid, sulfamic acid, and naphthenic acid.

On the other hand, as the transition metal complex, a complex with β-diketone or β-keto acid ester is used.
Examples of the diketone or β-keto acid ester include acetylacetone, ethyl acetoacetate, 1,3-cyclohexadione, methylenebis-1,3-cyclohexadione, 2-benzyl-1,3-cyclohexadione, and acetyltetra. Ron, palmitoyltetralone, stearoyltetralone, benzoyltetralone, 2-acetylcyclohexanone, 2-benzoylcyclohexanone, 2
-Acetyl-1,3-cyclohexanedione, benzoyl-p-chlorobenzoylmethane, bis (4-methylbenzoyl) methane, bis (2-hydroxybenzoyl)
Methane, benzoylacetone, tribenzoylmethane,
Diacetylbenzoylmethane, stearoylbenzoylmethane, palmitoylbenzoylmethane, lauroylbenzoylmethane, dibenzoylmethane, bis (4-chlorobenzoyl) methane, bis (methylene-3,4-dioxybenzoyl) methane, benzoylacetylphenylmethane, stearoyl (4 -Methoxybenzoyl) methane, butanoylacetone, distearoylmethane, acetylacetone, stearoylacetone, bis (cyclohexanoyl) -methane and dipivaloylmethane can be used.

3. Production of Oxygen Absorbing Layer In the case where the oxygen absorbing layer contains a gas barrier resin that does not substantially oxidize, an oxidizable organic component and a transition metal catalyst, the gas barrier resin is a polyamide resin as an example. To do. The oxidizable organic component is
0.01 to 10% by weight based on the polyamide resin,
In particular, it is preferably contained in an amount of 0.5 to 8% by weight. In addition, the transition metal-based catalyst is 100 to 3000 ppm as a transition metal amount based on the polyamide resin, specifically 100 to 800 ppm for cobalt and 150 for iron.
~ 1500ppm, 200 ~ 2000pp for manganese
It is preferably contained in an amount of m. Various means can be used to mix the oxidizable organic component and the transition metal-based catalyst with the polyamide resin. In this formulation,
There is no particular order and blending may be done in any order. For example, a blend of both can be easily prepared by dry blending or melt blending an oxidizable organic component with a polyamide resin. On the other hand, since the transition metal catalyst is a small amount as compared with the polyamide resin and the oxidizable organic component, the transition metal catalyst is generally dissolved in an organic solvent and the solution and powder or granular polyamide are used in order to perform the blending uniformly. It is advisable to mix the resin and the oxidizable organic component and optionally dry the mixture under an inert atmosphere.

Solvents for dissolving the transition metal catalyst include alcohol solvents such as methanol, ethanol and butanol, ether solvents such as dimethyl ether, diethyl ether, methyl ethyl ether, tetrahydrofuran and dioxane, methyl ethyl ketone and cyclohexanone. A hydrocarbon solvent such as a ketone solvent or n-hexane or cyclohexane can be used, and it is generally preferable that the transition metal catalyst is used at a concentration of 5 to 90% by weight. The mixing of the polyamide resin, the oxidizable organic component and the transition metal-based catalyst, and the subsequent storage are preferably carried out in a non-oxidizing atmosphere so that the oxidation in the previous stage of the composition does not occur. For this purpose, mixing or drying under reduced pressure or in a nitrogen stream is preferred. This mixing and drying can be performed at a pre-stage of the molding process using a vent-type or dryer-equipped extruder or injection machine.

In addition, a masterbatch of a polyamide resin and / or an oxidizable organic component containing a transition metal catalyst in a relatively high concentration is prepared, and this masterbatch is dry blended with an unblended polyamide resin to prepare the present invention. It is also possible to prepare the oxygen absorbing layer of. The polyamide used in the present invention is preferably dried at a temperature of 120 to 180 ° C., which is a general drying condition, under a reduced pressure of 0.5 to 2 mmHg for 2 to 6 hours and used for molding described later.

Although not generally required, the oxygen absorbing layer 3 may optionally contain an activator known per se. Suitable examples of activators include, but are not limited to, polyethylene glycol, polypropylene glycol, ethylene vinyl alcohol copolymers, ethylene / methacrylic acid copolymers, hydroxyl group- and / or carboxyl group-containing polymers such as various ionomers. is there. These hydroxyl group- and / or carboxyl group-containing polymers are 30 parts by weight or less, especially 0.01 part by weight, per 100 parts by weight of the polyamide resin.
It can be added in an amount of from 10 to 10 parts by weight.

The oxygen absorbing layer contains a filler, a colorant, a heat stabilizer, a weather stabilizer, an antioxidant, an antiaging agent, a light stabilizer, an ultraviolet absorber, an antistatic agent, a lubricant such as metal soap and wax. A known resin compounding agent such as a modifying resin or a rubber can be compounded according to a formulation known per se. For example,
The incorporation of the lubricant improves the penetration of the resin into the screw. As the lubricant, a metal soap such as magnesium stearate and calcium stearate, a hydrocarbon type such as fluid, natural or synthetic paraffin, microwax, polyethylene wax, chlorinated polyethylene wax, and a fatty acid type such as stearic acid and lauric acid , Stearic acid amide, valmitic acid amide,
Oleic acid amides, esyl acid amides, methylene bis stearoamides, fatty acid mono amides such as ethylene bis stearoamides or bis amides, butyl stearate, hydrogenated castor oil, ester glycols such as ethylene glycol monostearate, Alcoholic compounds such as cetyl alcohol and stearyl alcohol, and mixed systems thereof are generally used. The amount of the lubricant added is suitably in the range of 50 to 1000 ppm on the basis of polyamide.
Even when the oxygen absorbing layer is a combination of an oxidizable organic component and a transition metal catalyst, it is produced according to the method described above.

[Production of Inorganic Membrane Layer] 1. Treatment method As the treatment method for forming an inorganic film layer on the inner layer surface of the plastic multi-layer container using the treatment gas described above, the outer layer surface, or the inner and outer layer surfaces, a microwave plasma CVD method utilizing microwave glow discharge, Alternatively, a high frequency plasma CVD method utilizing high frequency glow discharge may be used. However, in the high-frequency plasma CVD method, a vapor-deposited inorganic film layer is formed by using high-frequency glow discharge. For that purpose, a so-called capacitive coupling type CVD device in which an internal electrode is arranged inside the container and an external electrode is arranged outside the container. Therefore, there is a problem in that the device configuration becomes complicated and the operation becomes complicated.

On the other hand, microwave plasma CVD
In the method, since microwave discharge is used indoors, it is not necessary to dispose internal electrodes or external electrodes, and the configuration of the device can be extremely simplified.

2. Processing gas For the purpose of CVD (Chemical Vapor Deposition), a processing gas used is one in which a compound containing atoms, molecules or ions forming a thin film is put in a gas phase and placed on an appropriate carrier gas. The raw material compound needs to be highly volatile, and silicon tetrachloride, silane, an organic silane compound, an organic siloxane compound or the like is used for forming the silicon film. Hydrocarbons such as methane, ethane, ethylene, acetylene and benzene are used for forming the carbon film and the carbide film. Further, oxygen gas is used for forming the oxide film, and nitrogen gas or ammonia gas is used for forming the nitride film. On the other hand, as the carrier gas, argon,
Neon, helium, xenon, hydrogen, etc. are suitable.

[0070]

[Example] 1. Method for Measuring Elastic Modulus ε of Inner Layer, Outer Layer, and Oxygen Absorption Layer Length 127 mm that constitutes the inner layer, outer layer, and oxygen absorption layer,
A sample piece having a width of 12.7 mm and a thickness of 6.25 mm was placed on two fulcrums with a distance between fulcrums of 101.6 mm, and a load was applied to the central portion at a constant speed to obtain a load-deflection curve. (AST
MD 790) The bending elastic modulus ε was calculated by the following equation (1). ^{ε = (L 3/4 *} b * h 3) * (F / Y) L: distance between supports (mm) b: width of the test piece (mm) h: thickness of the sample piece (mm) F: Load - Load (N) at an arbitrarily selected point on the first straight line of the deflection curve Y: Deflection amount at load F (mm)

2. Carbon dioxide permeation amount of container: Q1 Dry ice was put in a multi-layer bottle to be measured, heat-sealed with a lid material containing aluminum foil, and the weight (W0) was measured. The multilayer bottle was stored in a thermo-hygrostat at 30 ° C. and 80 RH, and after 31 days (1 month), the weight (W1) of the multilayer bottle was measured. As for the amount of dry ice, when the dry ice was completely vaporized, the amount of the dry ice was 3 times the full-filled internal volume of the multilayer bottle. 1 from the weight of this multi-layer bottle
Carbon dioxide permeation amount of bottle for a month (CO2TR: cc /
Month / bottle / atm) was obtained from the following formula. CO2TR = (W0-W1) * 22400/44/3

3. Brittleness evaluation For the brittleness evaluation of the oxygen absorption layer or the inorganic film layer, a multilayer bottle to be evaluated is filled with water at 20 ° C. to the mouth and capped.
The bottle was dropped once from a height of 0 cm so that the bottom surface and the side surface of the bottle hit the concrete floor surface, and the presence or absence of breakage, delamination, and leakage was examined and evaluated as brittleness. [JI
Drop test of SZ1703-1976 (polyethylene bottle)]

[Example 1] (Pressure resistant bottle) In the co-injection molding machine, the flexural modulus ε1 was 3.43 GP.
Polyethylene terephthalate (manufactured by Mitsubishi Gas Chemical Co., Inc.) a (ASTM D790) was supplied to the inner layer, middle layer and outer layer injectors. On the other hand, the flexural modulus after drying is 4.
41 GPa (ASTM D790) poly (m-xylylene adipamide) resin pellets [6007 (AEG = 2
7 eq / 10 ⁶ g / pellet value: Mitsubishi Gas Chemical Co., Inc.
Manufactured)), a pellet made of an oxygen-absorbing barrier material to which cobalt neodecanoate (DICATE 5000: manufactured by Dainippon Ink and Chemicals, Inc.) was added as a transition metal-based catalyst in an amount of 400 ppm in terms of cobalt amount, and an injection machine for an oxygen-absorbing layer Supplied to. The temperature of the injection nozzle of these injection machines was 280 ° C., and the resin pressure was 24.5 MPa.
A two-kind five-layer preform in which an oxygen absorbing layer made of an oxygen absorbing barrier material was provided between the inner layer and the intermediate layer and between the intermediate layer and the outer layer was produced. Furthermore, this preform is 100
After heating to ℃, using a mold at room temperature, the draw ratio is 2.4
Double, 2.9 times the width, and 6.96 times the area were subjected to biaxial stretching blow molding to form a multi-layer bottle having a circular cross-sectional shape of 2 layers and 5 layers with an internal capacity of 500 ml. At this time, the surface ten-point average roughness (Rz) of the inner layer surface of the multilayer bottle was 10 nm, and the center line average roughness (Ra) was 2 nm. Then, a 30-nm-thick silicon oxide film layer was provided on the inner layer surface of the multi-layer bottle by the microwave plasma CVD method, and the carbon dioxide gas permeation amount was measured, evaluated, and the brittleness was evaluated.

[Example 2] (Pressure resistant bottle) In Example 1, the surface ten-point average roughness (Rz) of the outer layer surface of the multilayer bottle was set to 23 nm and the center line average roughness (Ra) was set to 9 nm. The same measurement and evaluation were performed using the same multi-layer bottle except that a silicon oxide film layer having a thickness of 50 nm was provided.

[Example 3] (Heat-resistant pressure bottle) By the same method as in Example 1, a preform of 2 layers of 5 layers was produced. After crystallizing the mouth portion of this preform by an appropriate means, the preform is heated to a temperature not lower than the glass transition point of 11
By heating to 0 ℃, the mold temperature is 60 ℃
Biaxial stretch blow molding with a draw ratio of 3.0 times in the longitudinal direction, 3.0 times in the lateral direction, and 9 times in the area was performed to obtain a primary molded product having a final molded product larger than polyester. Next, the bottom, body and shoulders of the obtained primary molded product were heated in an oven at 800 ° C. for 5 minutes.
By heating for 2 seconds, the surface temperature is 150 ℃ on average
And heat-shrinked to obtain a secondary molded product.
Next, the heat-shrinkable secondary molded article is biaxially stretch blow molded with a secondary mold having a mold temperature of 60 ° C., and the internal volume is 500.
A 2-ml 5-layer multi-layer bottle was molded. At this time, the surface ten-point average roughness (Rz) of the inner layer surface of the multilayer bottle was 10 n.
m, the centerline average roughness (Ra) was 2 nm, and a multilayer bottle provided with a 20 nm silicon oxide film on the inner layer surface by the same method as in Example 1 was used to measure, evaluate, and evaluate brittleness of carbon dioxide gas. went.

[Example 4] (Heat-resistant bottle) In Example 3, the surface ten-point average roughness (Rz) of the outer layer surface of the multilayer bottle was set to 18 nm, the center line average roughness (Ra) was set to 6 nm, and the outer layer was prepared. The same measurement and evaluation were performed using the same multilayer bottle except that a 60 nm silicon oxide film layer was provided on the surface.

[Comparative Example 1] (Pressure resistant bottle) As in Example 1, except that the silicon oxide film formed by the microwave plasma CVD method was not provided on the inner layer surface of the multilayer bottle after the biaxial stretch blow molding. The same multi-layer bottle was used and the same measurement and evaluation were performed. As a result, it was found that the amount of carbon dioxide gas permeation was large.

[Comparative Example 2] (Pressure resistant bottle) In Example 2, the same measurement and evaluation were carried out by using the same multilayer bottle except that the silicon oxide film layer was not provided on the outer surface of the multilayer bottle.

[Comparative Example 3] (Heat-resistant pressure bottle) The same measurement and evaluation as in Example 3 were carried out with the same multilayer bottle except that the silicon oxide film was not provided on the inner layer surface of the multilayer bottle. As a result, it was found that the amount of carbon dioxide gas permeation was large.

[Comparative Example 4] (Heat-resistant pressure bottle) The same multi-layer bottle was used as in Example 4 except that the silicon oxide film was not provided on the outer surface of the multi-layer bottle, and the same measurement and evaluation were performed. As a result, it was found that the amount of carbon dioxide gas permeation was large.

[Comparative Example 5] (Pressure resistant bottle) In Example 2, microwave plasma CVD was performed on the oxygen absorbing layer without forming the outer layer made of thermoplastic polyester.
A multilayer bottle similar to that of Example 1 except that a silicon oxide film was provided by the method, and the same measurement and evaluation as in Example 1 were performed. As a result, although the carbon dioxide gas permeation amount was small, it was found in the brittleness evaluation that the inorganic film layer was cracked due to the delamination of the oxygen absorption layer and the carbon dioxide gas permeation amount was increased.

[Comparative Example 6] (Heat-resistant pressure bottle) In Example 4, microwave plasma CVD was performed on the oxygen absorbing layer without forming the outer layer made of thermoplastic polyester.
The same measurement and evaluation as in Example 2 were performed using the same multi-layer bottle as in Example 2 except that a silicon oxide film was provided by the method. As a result, although the carbon dioxide gas permeation amount was small, it was found in the brittleness evaluation that the inorganic film layer was cracked due to the delamination of the oxygen absorption layer and the carbon dioxide gas permeation amount was increased.

Table 1 shows the results of measurement, evaluation and brittleness evaluation of carbon dioxide permeation amount and oxygen permeation amount in Examples and Comparative Examples.

[0084]

[Table 1]

From the results shown in Table 1, it is understood that the plastic multilayer container of the present invention can surely prevent permeation of carbon dioxide gas, and that the brittleness of the oxygen absorbing layer and the inorganic film layer is suppressed. In addition, in the comparative example, providing the silicon oxide film on the oxygen absorption layer by the microwave plasma CVD method without forming the inner layer made of the thermoplastic polyester produces the same result as the comparative examples 5 and 6. thing,
Further, since it is clear that it is unsuitable as a plastic multi-layer container from the viewpoint of flavor, the measurement, evaluation and brittleness evaluation of the carbon dioxide permeation amount are not carried out as a comparative example.

In the examples and comparative examples, the breakdown voltage,
Although a heat-resistant multi-layer bottle was evaluated, the plastic multi-layer container of the present invention can be applied to a heat-resistant multi-layer bottle that is heat-sterilized when filling and sealing a beverage such as fruit juice, coffee, or tea. . In addition, the plastic multilayer container of the present invention includes a multilayer sheet vacuum formed, pressure formed, stretch formed,
It can also be applied to a container form such as a cup formed by plug assist molding or the like.

[0087]

According to the plastic multi-layer container of the present invention, while preventing the permeation of carbon dioxide gas and trapping the residual oxygen in the resin to a high degree, even when the oxygen absorbing layer and the inorganic film layer are present, It is possible to obtain a plastic multilayer container in which cracks due to deterioration of the oxygen absorption layer are prevented from being transmitted to the inorganic film layer and the inorganic film layer is prevented from being lost. Further, it is possible to provide a plastic multilayer container capable of improving the brittleness of the oxygen absorbing layer and the inorganic film layer and preventing cracks and peeling due to deformation of the container.

[0088]

[Brief description of drawings]

FIG. 1 is an enlarged sectional view of a main part of a plastic multilayer container of the present invention.

FIG. 2 is an enlarged cross-sectional view of a main part of another plastic multilayer container of the present invention.

FIG. 3 is an enlarged sectional view of a main part of still another plastic multilayer container of the present invention.

[Explanation of symbols]

1: Main parts of plastic multi-layer container 2: Inner layer 3: Oxygen absorption layer 4: Outer layer 5: Inorganic film layer

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) B65D 65/40 B65D 81/26 L 81/26 1/00 B (72) Inventor Masao Miyata Yokohama City, Kanagawa Prefecture 22-4, Okazawa-cho, Hodogaya-ku F-term in Soyo Research Institute, Toyo Seikan Group (reference) 3E033 AA01 BA06 BA07 BA17 BA21 BB08 CA16 CA20 FA02 FA03 GA02 3E067 AA03 AB26 AC01 BA03A BB14A BB25A BC03A CA04 CA30 FA01 AD04 BA04 A02 GB04 A4 GB01 BA33 BB03 BB05 CA11 4F100 AA00D AA00E AA20D AA20E AK01A AK01B AK01C AK41A AK41C AK46B BA03 BA04 BA05 BA06 BA07 BA10A BA10C BA10D BA10E BA26 CA09B DD07A DD07C EH66 EJ38A EJ38C GB16 JB16A JB16B JB16C JD02B JD14B JK07A JK07B JK07C YY00A YY00C

Claims (11)

[Claims] 1. An inner layer and an outer layer made of a thermoplastic resin,
A plastic multilayer container having an oxygen absorbing layer between the inner layer and the outer layer, and an inorganic film layer provided on the surface of the inner layer and / or the outer layer. 2. The relationship between the bending elastic modulus ε1 of the thermoplastic resin layer of the inner layer and / or the outer layer provided with the inorganic film layer and the bending elastic modulus ε2 of the thermoplastic resin of the oxygen absorbing layer is ε1 <ε.
The plastic multi-layer container according to claim 1, which is 2. 3. The surface roughness (JIS B0601) of the surface of the inner layer and / or the outer layer on which the inorganic film layer is formed has a ten-point average roughness (Rz) of 25 nm or less and 10 nm.
The plastic multilayer container according to claim 1, which has the following center line average roughness (Ra). 4. The plastic multilayer container according to claim 1, wherein the inorganic film layer is a silicon oxide film. 5. The silicon oxide film layer has a thickness of 2 to 50.
The plastic multilayer container according to claim 4, which has a thickness of 0 nm. 6. The plastic multilayer container according to claim 1, wherein the oxygen absorption layer contains an oxidizable organic component and a transition metal catalyst. 7. The plastic multilayer container according to claim 6, wherein the oxidizable organic component is a gas barrier resin. 8. The plastic multilayer container according to claim 7, wherein the gas barrier resin is a xylylene group-containing polyamide. 9. The plastic multilayer container according to claim 1, wherein the oxygen absorbing layer contains a gas barrier resin that does not substantially oxidize, an oxidizable organic component, and a transition metal catalyst. 10. The plastic multilayer container according to claim 6, wherein the transition metal catalyst is a cobalt salt. 11. The inner layer and the outer layer are polyester resins and are biaxially stretch blow molded.
The plastic multi-layer container according to any one of 1.