JP2001062963A - Transparent plastic multilayer molding container - Google Patents

Abstract

PROBLEM TO BE SOLVED: To incorporate particularly high oxygen barrier properties and to further remove an oxygen in a container by sequentially laminating a transparent thermoplastic resin layer, a resin layer containing an oxygen capturable resin and a transparent thermoplastic resin layer from an inside, vacuum molding, pressure forming, blow molding or injection molding the resultant laminate. SOLUTION: A layer configuration from an inner layer to an outer layer is manufactured by sequentially laminating a transparent thermoplastic resin layer, a resin layer containing an oxygen capturable resin and a transparent thermoplastic resin layer from an inside, vacuum molding, pressure forming, blow molding or injection molding the resultant laminate. As the transparent thermoplastic resin, a PEN, PAR, PC and amorphous polyamide are excellent in view of heat resistance, productivity or the like. As the transparent oxygen capturable resin, a polyester, polyamide, polyolefin or vinyl polymer in which a polyolefin oligomer segment having a carbon-carbon unsaturated bond in a molecule is used, and as the polyester polymer, for example, a PET, PEN or the like is used.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a container having transparency, excellent ultraviolet barrier properties, small heat shrinkage at high temperatures, and good heat resistance. The present invention also relates to a highly functional transparent plastic multilayer molded container having sufficient dimensional stability, particularly having a high oxygen barrier property, and further having a performance of removing oxygen in the container without using an oxygen removing agent.

[0002]

2. Description of the Related Art Chemicals which are easily oxidized or not to be oxidized, beverages and powders requiring aroma such as green tea, black tea, laver and coffee, cooked foods (retort foods) or oxygen or air. Conventionally, glass is used as a container for small precision equipment parts that do not want to come into contact with objects such as solids and liquids that do not like to be in contact with air because they are easily oxidized by contact with oxygen gas, such as easily oxidizable metals and materials. Containers made of metal such as bottles, iron, copper or aluminum are used.As plastic molding containers, thermoplastic resin molding containers with excellent processability, especially gas-permeable resins such as oxygen-permeable polyolefin resins, and aluminum in some shapes A multilayer molded container having laminated foils has been used.

[0003] Aluminum containers have advantages such as light weight, high-temperature filling, food retort sterilization adaptability, excellent recyclability, gas barrier properties, impact resistance, ultraviolet barrier properties, light shielding properties, and beautifulness. It appears to be a very ideal material for packaging materials that are easily oxidizable or must not be oxidized. On the other hand, the raw materials are expensive, and the production facilities such as the production facilities for hermetic aluminum containers and the facilities for filling the contents require large-scale, high-performance facilities, and require extremely large investment amounts. Yes, it can only deal with small varieties and mass production.

[0004] Aluminum containers are poor in elasticity in material, require corrosion-resistant treatment when the contents are corrosive, and the product price is high. In addition, the containers lack microwave oven cooking adaptability and become large. In the food market or daily necessities, it is one of the major product concepts that the packaging material is transparent and the contents are visible, but this is lacking. It is mainly used for small containers for beer. On the other hand, aluminum foil as a container is rarely used alone, and is often used as a laminate film by laminating it with a thermoplastic resin such as a polyolefin resin. These have almost the advantages of aluminum containers, such as light weight, airtightness, and light-shielding properties.Although they have the flexibility lacked in the containers, they do not have microwave cooking properties or form retention, and retain their form. It is difficult to use as a multi-layer molded container for contents requiring the property. Furthermore, since there is no function to remove oxygen such as air when present in the container, there is a problem that when a complete anoxic state is required, an oxygen absorber must be disposed in the container. .

Glass containers that have been used as gas barrier containers for a long time include retort sterilization adaptability, microwave cooking adaptability, recyclability, gas barrier properties, corrosion resistance, and the like.
It has excellent performance such as excellent resealability, shape retention, and transparency, can be used for large-mix low-volume production, and can be manufactured at relatively low product prices. However, there is no flexibility compared to other packaging materials, so there is a limitation in filling the contents, and furthermore, the weight of the packaging material is heavy and the impact resistance is extremely weak. It is used as a container for liquids that have been used in the past. When a completely oxygen-free state is required, an oxygen absorber must be provided in the container.

[0006] In addition to the above, there is a paper pack as a small container or a small packaging container. Since these have no gas barrier property by paper alone, laminate aluminum foil,
Alternatively, a large number of products in the form of a composite material coated or laminated with a thermoplastic resin such as a polyolefin resin or a thermosetting resin are on the market. These packaging materials are lightweight, have excellent impact resistance, light-shielding properties, and shape retention, require a small investment in equipment, and can be used for low-volume, high-mix, low-volume production. Lack of adaptability to microwave cooking, lack of gas barrier properties, easily oxidize contents, small shelf life, invisible contents, lack of luxury, etc. Mainly used. When a completely oxygen-free state is required, an oxygen absorber must be disposed in the container, but it is disadvantageous for long-term storage because of the problem of hermeticity.

On the other hand, a molded container using a thermoplastic resin, in particular, a polyolefin, can easily impart retort sterilization and can be easily made transparent, and is lightweight, impact-resistant, corrosion-resistant, workable, and has a microwave oven. Excellent cooking adaptability,
Although the product price is inexpensive, it can be easily adapted to packaging by automatic packaging lines, the capital investment for these is small, and it is an excellent packaging material that can be used for containers of high-mix low-volume production. the resin molded container generally gas barrier is low, dislike oxide in terms of quality, and as the container contents dislike permeation of CO ₂ gas, oxygen gas permeability, C
It has a serious disadvantage of high O ₂ gas permeability. As a measure for improving the gas barrier property of a molded container using polyolefin as a structural material resin, many transparent plastic multilayer molded containers in which a gas barrier resin is laminated on a structural material resin have been proposed.

When mechanical strength is required, polyethylene terephthalate (hereinafter referred to as "PET") is widely used as a rigid thermoplastic resin.
The resin is a thermoplastic resin having a higher melting point than polyolefin, and becomes a transparent molded article when stretched, and can be made into a lightweight and impact-resistant, corrosion-resistant molded container, so that mineral water, black tea, tea, It is widely used as a container for liquids such as oolong tea, or as a container for various solids, but has no carbon dioxide gas barrier property, insufficient heat resistance, has a low glass transition temperature, and is filled with hot water of about 90 ° C. Shrinkage is unavoidable, and because of its low strength retention at high temperatures, it cannot be filled at high temperatures,
There is a problem in gas barrier properties and use at high temperatures, such as inability to use as a microwave cooking container. Also in this case, it is necessary to use a deoxidizer to remove oxygen in the container.

As a method of manufacturing the above-mentioned gas-barrier multilayer molded container, a thermoplastic plastic such as a polyolefin resin and a saponified ethylene-vinyl acetate copolymer (ethylene-vinyl alcohol copolymer; hereinafter referred to as "EVO") are used.
H ". ), A barrier resin such as polyvinylidene chloride or polyacrylonitrile is formed into a laminate sheet by multilayer extrusion using the barrier resin as an intermediate layer, and then subjected to secondary molding to form a multilayer molded container, or the gas barrier properties described above. Multilayer molded containers have been manufactured by laminating resin alone by blow molding or injection molding using a gas barrier resin as an intermediate layer.

The above-mentioned multilayer molded container can significantly improve the gas barrier property as compared with a single-layer container of a thermoplastic resin such as a polyolefin resin. However, even in a molded container using such an improved transparent plastic multilayer molded container, the gas barrier resin layer used there has a slight gas permeability, so that it can be stored for a long period of time or completely oxygenated. When it is necessary to eliminate the oxygen, it is inevitable that the oxygen barrier property becomes insufficient as compared with a glass container or a metal can. On the other hand, even in containers such as glass containers and metal cans with excellent gas barrier properties, oxygen in the air existing above the contents in the container cannot be removed, so that oxidation of the contents cannot be avoided, and the contents are inevitable. It was not possible to reliably prevent contact between oxygen and oxygen. Therefore, in order to reliably prevent the contact between the contents and oxygen, it is not sufficient to completely complete the gas barrier properties of the multilayer molded container, and oxygen present inside the molded container after filling can be removed,
Iron compound-based oxygen scavengers for preventing contact between oxygen and contents have been developed, and they have been sealed in molding containers.

In order to effectively use the oxygen absorber, a high-humidity atmosphere is required, and in the presence of carbon dioxide, there is a problem that the use is restricted. Occasionally, infants and the like are mistaken for food and eat this oxygen absorber, so there is a high risk of taking this measure. Furthermore, since there is no air flow in the molding container, deoxidation with this type of oxygen absorber is localized, and uniform deoxidation in the container cannot be achieved. In order to perform uniform deoxidation, it is necessary to arrange an oxygen scavenger over the entire container. For this purpose, it is conceivable to mix it with the constituent material of the container, but in such a case, there is a problem that the mechanical properties of the resin and the resin processability cannot be avoided. As another means, filling is performed in an atmosphere of nitrogen gas or the like.However, it is difficult to make the entire interior of the molding container oxygen-free, and the intrusion of oxygen from the outside is difficult. Even if it is prevented, the oxygen present at the time of filling becomes impossible unless a deoxidizer is present.

[0012]

DISCLOSURE OF THE INVENTION The present invention is lightweight, has excellent mechanical properties, chemical resistance, transparency, and ultraviolet barrier properties, has small heat shrinkage at high temperatures, and has a shrinkage rate even with hot water. A heat-resistant container with low water absorption and high strength retention even at high temperatures, filled with high temperature, retorted,
Highly functional transparent plastic multi-layer molded container that has sufficient dimensional stability even in microwave cooking, etc., has particularly high oxygen barrier properties, and has the ability to remove oxygen in the container without using an oxygen remover. The purpose of the development.

[0013]

According to the present invention, there is provided [1] a layer structure from an inner layer to an outer layer, wherein a transparent thermoplastic resin layer /
A transparent plastic multilayer molded container, which is laminated in the order of a resin layer containing an oxygen-supplementary resin / a transparent thermoplastic resin layer, and manufactured by vacuum molding, pressure molding, blow molding or injection molding;

[2] The above-mentioned [1], wherein the oxygen-scavenging resin is a polyester, polyamide, polyolefin or vinyl polymer having a polyolefin segment having a carbon-carbon unsaturated bond in the molecule. [3] The oxygen-scavenging resin is a polymer comprising 1 to 15% by weight of a polyolefin oligomer segment having a carbon-carbon unsaturated bond and 85 to 99% by weight of a main polymer segment, and The transparent plastic multilayer molded container according to the above [1] or [2], which contains 50 to 500 ppm of a transition metal compound as an atom, [4] having a sensitizing effect on an oxygen-scavenging resin layer with respect to ultraviolet light and / or visible light. The transparent plastic according to the above [2] or [3], further comprising a photo-oxidation promoter. Chick multilayer molded container, [5]
The polyolefin oligomer segment in the oxygen-scavenging resin contains any one of polymerized oligomer units of butadiene, norbornene, dicyclopentadiene, and isoprene, and has a molecular weight of 1,000 to 1,000.
The transparent plastic multilayer molded container according to any one of [2] to [4] above, wherein the polyolefin oligomer segment having a carbon-carbon unsaturated bond in the oxygen-scavenging resin is a main polymer. The above-mentioned [2], which is an oxygen-scavenging resin bonded as a main chain of a segment or as a pendant in a branched manner.
Or a transparent plastic multilayer molded container according to any one of [5] to [5],

[7] Transparent thermoplastic resin is polyethylene naphthalate (hereinafter referred to as “PEN”),
Polyarylate (hereinafter referred to as "PAR"), transparent polypropylene (hereinafter referred to as "transparent PP"), cyclic polyolefin (hereinafter referred to as "cyclic PO"), amorphous polyamide (hereinafter referred to as "amorphous nylon"), Polymethylpentene-1, polystyrene (hereinafter referred to as “PS”),
Amorphous polyethylene terephthalate (hereinafter “Amorphous PET”)
That. The transparent plastic multilayer molding according to any one of the above [1] to [5], which is a kind of resin selected from a resin, a polycarbonate (hereinafter, referred to as “PC”) and a polyacrylonitrile (hereinafter, referred to as “PAN”). [8] The container, and [8] the PEN layer is a copolymer containing at least 80% by weight of a PEN component, and the PAR layer is a copolymer containing at least 80% by weight of a PAR component or a resin blended with them. The above object has been achieved by developing a transparent plastic multilayer molded container described in [7].

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION The transparent plastic multilayer molded container referred to in the present invention has an oxygen-capturing resin layer and needs to be transparent, and is not limited to a production method and a shape. Multi-layered container formed by performing a secondary forming process such as vacuum forming, pressure forming, etc. of the formed multilayer sheet, a multi-layered container formed by stretching and blowing a multi-layer preform formed by multi-layer blow molding or injection molding, Means molded by various manufacturing methods, such as a multilayer molded container molded by multi-layer injection molding or multi-stage injection molding, the lid is of the same type as the container body, an easy peel aluminum foil laminate, or a filling port It also includes a multi-layer molded container with a separate outlet, which can be filled at high temperature, can be sterilized by retort, and has a lid The container is adapted to microwave cooking as it is, and it is a multilayer molded container having shape retention, and it is possible to reliably capture oxygen entering the container from the atmosphere and only reduce the amount of penetration. Instead, the oxygen gas in the dead space of the container is supplemented to ensure zero oxygen in the container. As a result, the packaging container body is transparent and the multilayer molded container using the present multilayer molded container has a long shelf life and does not use a deoxidizer, so there is no problem even if the moisture is low, and at the time of filling. This is a transparent plastic multilayer molded container capable of capturing oxygen in the container, which need not be performed in a nitrogen atmosphere.

In the present invention, the transparent thermoplastic resin includes transparent resins such as PEN, PAR, transparent PP, cyclic PO, amorphous nylon, polymethylpentene, PS resin, polysulfone, amorphous PET, PC or PAN. However, the present invention is not limited to this as long as it is transparent, and among the objects of the multilayer molded container of the present invention, the container has transparency, can be filled at high temperature and can be retorted, and can be cooked in a microwave oven. All transparent resins can be used as long as they have the properties and the ability to remove oxygen in the container, and can satisfy the performance required of the contents. Among these, PEN, P
AR, PC and amorphous polyamide are high in cost, but are excellent in performance including physical properties such as heat resistance and productivity.

PEN is produced by transesterification of naphthalene-2,6-dicarboxylic acid with ethylene glycol (actually, transesterification of 2,6-dimethylnaphthalate with ethylene glycol or deglycolization of di (hydroxyethyl) naphthalate). The glass transition temperature is higher than that of PET (110 ° C. versus 78 ° C.), and the shrinkage rate is 1% even when filled with hot water at 100 ° C. (PET is 5%). And the heat resistance is much better than PET. In addition to excellent mechanical strength, hydrolysis resistance, dimensional stability, and low adsorption,
ET lacks gas barrier properties and UV barrier properties and devitrifies even at high temperatures (PET devitrifies at high temperatures)
It is an excellent resin such as having transparency without performing. Therefore, if the food is cooked, it can be filled at high temperature as it is, and because of its high strength, the price is higher than PET, but the weight can be reduced. Also, the gas barrier properties lacking in PET (oxygen is about 1 / 4, about 1/5 of carbon dioxide). However, gas barrier properties are not zero.

PAR is a polycondensate of an aromatic dicarboxylic acid and a dihydric phenol, and has sufficient transparency, low oxygen permeability, low water vapor permeability, high heat resistance, and high heat resistance as compared with PET. High mechanical properties such as impact strength and elastic modulus, excellent flame retardancy, high dimensional stability in molding,
It is a resin that has ultraviolet impermeability and stability against ultraviolet rays and is generally superior to PET, and has no problem as an exterior material for containers. However, since it has a slightly lower chemical resistance like PET and PAR often uses bisphenol as a raw material for synthesis, there is no problem when used as a container for articles other than food at normal temperature. When used as a food container, it may be exposed to high temperatures, so it is better to avoid using it as an interior material.

In the present invention, the copolymer or blended resin in which PEN contains a PEN component or PAR contains 80% by weight or more of PAR component is also used as PEN or PEN.
Classify as AR. All of these are PEN, the main component
Or, it has the same performance as PAR. Transparent P
P is polypropylene blended with a transparent crystallization agent,
The translucent polypropylene has been widely used in the fields of injection molding, blow molding, and the like because of its transparency. The cyclic PO is a cyclic olefin copolymer obtained by copolymerizing ethylene with norbornene or the like, and is a polymer having high transparency and high rigidity and low water vapor permeability, and is suitable for manufacturing a molded article. Although it cannot be clearly defined as an amorphous nylon, it means a nylon that gives a transparent molded article under ordinary melt molding conditions and does not cause devitrification even when the molded article is subjected to heat treatment and water absorption treatment. Many such resins are on the market, and Dynamit Nobel (Trogamid =
T), EMS (Grillamid TR55 = TR5)
There are many commercial products such as 5), Unitika (CX 1004, 1005) and Toyobo (Nylon 714).

The transparent oxygen-scavenging resin used in the multilayer molding container of the present invention includes polyester, polyamide, polyolefin or vinyl having a polyolefin oligomer segment having a carbon-carbon unsaturated bond in the molecule. And the like. Here, as the polyester polymer, for example, PE
T, PEN and the like. Examples of the polyamide-based polymer include aliphatic polyamides such as nylon 6, nylon 66, and nylon 12, and aromatic polyamides such as polyxylylenediamine adipamide (MXD6). Among them, MXD6 is a suitable resin as a material resin for a barrier package because the resin itself has gas barrier properties.

For example, the polyester or polyamide as the oxygen-scavenging resin in the present invention is prepared by using an olefin oligomer having two functional groups at one end as a part of the raw material compound when synthesizing the polymer. The polymer may be condensed, or the polymer may be reacted with an olefin oligomer having two functional groups at one end, and an olefin oligomer segment may be introduced by transesterification or transamidation. Further, at the time of polymer synthesis, a free functional group may be provided in the main chain using a raw material having three or more functional groups, and an olefin oligomer segment may be bonded to the free functional group. A transesterification or transamidation reaction may be carried out by reacting a starting material compound having the above functional group to introduce a functional group into the main chain, to which an olefin oligomer segment may be bonded.

In such a polyester-based polymer having a pendant olefin oligomer segment, a part of the dibasic carboxylic acid is replaced with an olefin oligomer having two carboxyl groups at one end in the polymer synthesis step, or A part of the glycol is replaced with an olefin oligomer having two hydroxyl groups at one end to carry out a polycondensation reaction to obtain a polyester having the olefin oligomer in a pendant form. Alternatively, a part of a dibasic carboxylic acid is replaced with a trivalent or higher polyvalent carboxylic acid, or a part of a glycol is replaced with a trivalent or higher polyhydric alcohol and copolycondensed to form a carboxyl or hydroxyl functional group Is provided in the middle of the main chain, to which an olefin oligomer is bonded.

Alternatively, an olefin oligomer having two carboxyl groups or two hydroxyl groups at one end may be transesterified to a normal polyester polymer to directly introduce an olefin oligomer segment, or a trivalent carboxylic acid, Preferably, an aromatic carboxylic acid is reacted, or a trihydric or higher polyhydric alcohol is reacted, and a free carboxyl group or a free hydroxyl group functional group is introduced into the polyester main chain by transesterification, and the functional group is added. May be combined with an olefin oligomer.

Similarly, in the case of polyamide, a method of copolycondensing an olefin oligomer having two carboxyl groups at one end or an olefin oligomer having two amino groups at one end at the time of synthesizing the polymer; A method of directly introducing the olefin oligomer by transamide reaction of the olefin oligomer, replacing a part of the dibasic carboxylic acid with a trivalent or higher polycarboxylic acid, or replacing a part of the alkylenediamine with a trivalent or higher carboxylic acid. A method in which a functional group of a carboxyl group or an amine group is provided in the middle of the main chain by replacing with an alkylene polyamine and copolycondensed, and an olefin oligomer segment is introduced. The transhydric alcohol reacts with the Introducing a functional group, to which there is a method of bonding the olefin oligomer segments.

The polycondensation polymer containing the olefin oligomer in the form of a block has a functional group capable of polycondensation at both terminals as a part of a raw material such as diamine, dicarboxylic acid or glycol at the time of its synthesis. By using an olefin oligomer having a carbon-carbon unsaturated bond and a molecular weight of 1,000 to 10,000, an olefin oligomer having a polyamide-based polycondensation-based polymer segment constituting the majority and a carbon-carbon unsaturated bond constituting a small portion A polycondensation polymer such as polyamide having segments bonded to the main chain in a block shape can be used. That is, in the synthesis of the above polyamide, carboxyl group at both ends, amino group, in some cases has a hydroxyl group,
Molecular weight of 1000 to 100 having carbon-carbon unsaturated bond
The olefin oligomer segment of No. 00 can be produced by mixing and reacting a dicarboxylic acid, which is a raw material of polyamide, with a diamine (a nylon salt is also acceptable) or a lactam.

Further, a polycondensation-based polymer of polyamide has a small molecular weight of 10 or more having an amino group, a hydroxyl group or a carboxyl group at both ends and having a carbon-carbon unsaturated bond.
By mixing olefin oligomers of 00 to 10000,
By performing a transamidation or transesterification reaction while melting, a polycondensation polymer having a polyolefin oligomer segment in the main chain of polyester or polyamide can be produced.

The olefin oligomer derivative used in the polycondensation reaction needs to have a carbon-carbon unsaturated bond in the olefin oligomer segment chain. Such oligomers include butadiene derivatives having a conjugated double bond such as butadiene and isoprene, and homo-oligomers and copolymers of non-conjugated dienes such as norbornene and dicyclopentadiene, and copolymers of these diene compounds with olefins such as ethylene and propylene. Polymerized oligomers can be mentioned. For these oligomers, it is necessary to introduce a functional group having a reactivity with a functional group bonded to the polycondensation polymer main chain. For this purpose, an oligomer containing a diene compound is formed by metathesis polymerization or anion living polymerization. Can be synthesized by introducing a functional group into the compound.

Further, in the present invention, the addition polymer segment of the oxygen-permeable addition-polymerization linear polymer having a reactive functional group (hereinafter referred to as reactive functional group (1)) is a polyolefin-based or vinyl-based polymer. If there is no particular limitation, ethylene, propylene, butene
Polyolefin resins such as 1,4-methylpentene-1 or other olefin homopolymers, copolymers or copolymers with vinyl monomers, styrene resins such as polystyrene homopolymers or copolymers, (meth) acrylic acid, The backbone is an acrylic copolymer containing (meth) acrylates such as methyl (meth) acrylate, ethyl (meth) acrylate, and 2-hydroxyethyl (meth) acrylate, and addition polymers of various polymers such as acrylonitrile and vinyl chloride. Polymer segments may be mentioned. Among them, a polymer segment which has a high oxygen permeability, is thermally stable and has excellent resin processability, or a material whose physical properties are close to required, is selected according to the purpose of use, and is preferably a polymer segment to which an oligomer can be easily bonded. Oxygen permeability is low in barrier properties of a polymer having a low oxygen scavenging property, and has a high degree of oxygen barrier properties like the oxygen scavenging polymer of the present invention, but as an oxygen scavenging polymer, its ability is low and insufficient. Become.

As a polymer for providing these segments, for example, a polymer having no reactive functional group (1) such as polyethylene, polypropylene, or polystyrene, an anhydride having a reactive functional group (1) can be used. A graft polymer obtained by graft polymerization of maleic acid or (meth) acrylic acid, or an ethylene- (meth) acrylic acid copolymer, an ethylene-glycidyl methacrylate copolymer, an ethylene-ethyl acrylate-maleic anhydride copolymer, Reactive functional groups such as styrene-glycidyl methacrylate copolymer, ethylene- or styrene-2-hydroxyethyl methacrylate copolymer (1)
And a polymer obtained by copolymerizing a monomer having the following formula: Further, a method of imparting a reactive functional group (1) to the addition polymer by modifying the addition polymer by hydrolysis or the like after copolymerizing vinyl acetate, acrylic acid ester or the like may be employed.

The reactive functional group (1) need not be limited in relation to the functional group of the olefin oligomer to be reacted therewith (hereinafter referred to as the reactive functional group (2)). Taking into account ease, stability, reactivity and the like, a carboxyl group, a hydroxyl group, an epoxy group, a carboxylic anhydride group or an amino group is preferred. When the reactive functional group (1) is a carboxyl group, the reactive functional group (2) of the olefin oligomer is selected from a hydroxyl group, an amino group, an epoxy group, an isocyanate group, and the like having reactivity with the functional group. The same applies to other cases.

When the olefin oligomer segment is introduced into the addition polymer, it is most effective to have an addition polymer having a reactive functional group (1) and a carbon-carbon unsaturated bond having a reactive functional group (2). The olefin oligomer is melt-kneaded using an apparatus capable of melt-kneading such as an extruder and a blender. Alternatively, the two may be reacted in the form of a solution. However, not only an organic solvent or the like is required, but also the solvent must be recovered later, which is troublesome and costly. Furthermore, EVO
Even in a vinyl-based polymer having a functional group itself, such as a vinyl-based copolymer containing H and (meth) acrylic acid as one component, an olefin oligomer segment can be introduced in the same manner as the polyolefin-based polymer. . In addition, the polymer itself may have an olefin oligomer segment, such as a butadiene-styrene copolymer and an acrylonitrile-butadiene-styrene copolymer.

As the oxygen-scavenging resin, oxygen is scavenged in an olefin oligomer segment having a carbon-carbon unsaturated bond active for oxygen. The reaction is initiated by abstraction of the hydrogen bonded to the carbon at the position, and eventually the carbon chain is cleaved from this part. Therefore, a polymer having an olefin oligomer segment in the main chain undergoes main chain cleavage. On the other hand, in a polymer in which olefin oligomer segments are bonded in a pendant form, the problem is only that the pendant olefin oligomer segments are cleaved. Even if the resin captures oxygen, the main chain that has a large effect on the physical properties is not affected at all. Will not be. In consideration of physical properties, a pendant-bound oxygen-scavenging resin is more preferable.

The olefin oligomer to be introduced includes a carbon-carbon unsaturated bond and its α in the oligomer molecule.
Bond having a carbon having a hydrogen at the -position [allyl bond =
(—CR ¹ ＣＨCH—CHR ² —), provided that R ¹ and R ²
Represents a hydrogen atom, a lower alkyl group or the like. ] Is necessary. Such a bond is obtained when a conjugated diene such as isoprene, butadiene, norbornene or a non-conjugated diene is polymerized or copolymerized. Among them, an olefin oligomer segment containing an isoprene segment has high oxygen scavenging activity.

The molecular weight of the olefin oligomer segment is determined by the transparency of the oxygen-scavenging resin, the type of the main constituent compound of the oxygen-scavenging resin, and whether the oligomer segment is introduced into the main chain or pendant. Appropriate numerical values cannot be obtained because they vary depending on the form, the type of the compound constituting the oligomer, the average number of oligomer segments introduced into one molecule of the oxygen-scavenging resin, and the number of carbon-carbon unsaturated bonds in the oligomer. When the number of segments is large, the molecular weight may be small, and when the number of introduced oligomer segments is small, the molecular weight tends to be large. Generally, the average is less than about 5 in one molecule of the oxygen-scavenging resin, and the transparency is low. When necessary, a butadiene oligomer having an oligomer molecular weight of 100
Those having about 0 to 10,000 can be used. When the molecular weight is smaller than this, the average introduced number becomes a larger number. In the case of a butadiene-styrene resin, an acrylonitrile-butadiene-styrene resin or the like, it is sufficient that the amount of butadiene required for the properties of the resin is copolymerized.

Since such an oxygen-scavenging resin alone has low reactivity with oxygen alone, it is necessary to add a catalytic amount of a transition metal compound to the resin in order to increase the reactivity. Suitable transition metal compounds include manganese, cobalt, nickel, copper, rhodium, ruthenium, and the like, most preferably cobalt. Preferred counter ions of these metals include chloride ion, acetate ion, stearate ion, palmitate ion, 2-ethylhexanoate ion, neodecanoate ion, naphthenate ion and the like, but are not limited thereto. Absent. Particularly preferred are cobalt stearate, cobalt 2-ethylhexanoate and cobalt neodecanoate. Alternatively, the transition metal compound may be an ionomer, which are well known in the art. The amount of the transition metal compound is in the range of 0.001 to 1%, preferably 0.01 to 03% of the weight of the oxygen-scavenging resin as a metal. Below the lower limit, the effect of promoting the reaction is not recognized, and even if it exceeds 1%, the effect is saturated and does not increase the reaction rate with oxygen, but merely lowers the physical properties and increases the cost. Only.

It is preferable to add a photo-oxidation accelerator (sensitizer) to the oxygen-scavenging resin layer in addition to the transition metal compound. Benzophenone, o-
Methoxybenzophenone, acetophenone, o-methoxyacetophenone, acenaphthenequinone, methyl ethyl ketone, valerophenone, hexanophenone, α-phenylbutyrophenone, p-morpholinopropiophenone, dibenzosuberone, 4-morpholinobenzophenone, benzoin, benzoin methyl ether, etc. It can be used but is not limited to this.

This photo-oxidation accelerator promotes the oxygen-scavenging rate of the oxygen-scavenging resin by exposure to light.
It varies depending on the type of oxygen-scavenging resin, wavelength and intensity of light, and the like. If the transparency of the resin is low, it is necessary to increase the amount of the photo-oxidation accelerator used. Usually, it is about 0.01 to 10% by weight, preferably about 0.1 to 1% by weight, based on the whole resin composition. The transition metal compound and the photo-oxidation accelerator are described in detail in JP-A-5-194949. Other methods of activating the oxygen-scavenging properties of the oxygen-scavenging resin include irradiation with radiation such as electron beams, γ-rays, and X-rays, ultrasonic waves for imparting α-hydrogen abstraction energy, high-frequency waves, heat (high The application of energy from the outside such as temperature) is also effective, and the combination thereof can shorten the induction period and increase the oxygen capture rate and oxygen capture rate.

Such an oxygen-scavenging resin may be used alone, or may be diluted with another transparent resin for cost reduction. The type of resin to be diluted is preferably a polyester-based oxygen-scavenging resin such as transparent PET or PEN, and a polyolefin-based oxygen-scavenging resin is compatible with the same resin such as transparent PP or cyclic PO. And the possibility that the resin layer becomes transparent is high. In this case, the blending amount of the oxygen-scavenging resin is also related to the thickness of the oxygen-scavenging resin layer, but it is possible to use an oxygen-scavenging resin having a concentration of at least 5%, preferably 20% or more.

Although the gas barrier layer of the multilayer molded container is not an essential requirement, when the gas barrier layer is provided, it is easy to maintain the oxygen barrier property of the multilayer molded container for a long period of time in order to suppress the intrusion of oxygen from the outside. become. The gas barrier layer has an effect of extending the oxygen supplement life of the multilayer molded container by laminating the gas barrier resin layer outside the oxygen supplement resin layer outside the oxygen supplement resin layer. As the gas barrier resin, a thermoplastic resin having a low oxygen permeability coefficient and being thermoformable is used. For example, EVOH, polyvinylidene chloride, MXD6, polyacrylonitrile, PETI
(Copolymer of ethylene glycol with terephthalic acid and isophthalic acid), PEN and the like. Among them, EVOH is most suitable in terms of the balance between oxygen barrier properties and cost. For example, an ethylene-vinyl acetate copolymer having an ethylene content of 20 to 60 mol%, particularly 25 to 50 mol%, is saponified so that the degree of saponification becomes 96 mol% or more, particularly 99 mol% or more. The resulting saponified copolymer is preferred. The EVOH should have a molecular weight sufficient to form a film and is generally at least 0.01 dl / g, especially at least 0.05 dl / g as measured at 30 ° C. in a mixed solvent of phenol: water at a weight ratio of 85:15. / G or more.

Another example of the gas barrier resin having the above-mentioned properties is MXD6. Although this resin does not have a high oxygen barrier property, it is a polyamide resin, and thus has a characteristic that an adhesive is not required for lamination with another polyamide or the like. This polyamide should also have a molecular weight sufficient to form a film and has a relative viscosity (η _rel ) measured at a concentration of 1.0 dl / g in concentrated sulfuric acid at a temperature of 30 ° C. of at least 1.1, in particular at 1. It is desirable that the number be 5 or more. In the present invention, the gas barrier resin used as the intermediate layer is not particularly limited as long as it has a high gas barrier property against oxygen and carbon dioxide gas and can be thermoformed.

Other examples of the gas barrier resin having the above-mentioned properties include polyvinylidene chloride, polyacrylonitrile, and the number of amide groups per 100 carbon atoms of 5 to 5
Polyamides and polyester copolymers in the range of 0, especially 6 to 20 can be used. These gas barrier resins also preferably have a molecular weight sufficient to form a film. For polyamide, 1.0 dl /
g at a temperature of 30 ° C. (η
_rel ) is preferably 1.1 or more, especially 1.5 or more.

[0043]

The present invention will be specifically described below with reference to examples, but the present invention is not limited to the following examples.

(Raw material resin for producing oxygen-supplementing resin) [Polyethylene naphthalate resin] PEN: Unipet NS76 manufactured by Nihon Unipet Co., Ltd.
3: Intrinsic viscosity (IV = 0.70) [Polyethylene naphthalate resin] PENT8: Nippon Unipet Co., Ltd., Unipet NS
663: intrinsic viscosity (IV = 0.72), PEN / PET
= 92 mol% / 8 mol% [Amorphous polyamide] TR55: manufactured by EMS, TR55: glass transition temperature 16
0 ° C., (Constituent monomer: isophthalic acid, 4,4′-diamino-3,3′-dimethyldicyclohexylenemethane,
Laurolactam)

[Polycarbonate] PC: Ubilon S2000, manufactured by Mitsubishi Gas Chemical Co., Ltd.
Glass transition temperature 150 ° C., [Polyarylate] PAR: manufactured by Unitika Ltd., U-polymer U-100, glass transition temperature 193 ° C., [styrene resin = PS] PS / SB: PS: manufactured by Asahi Chemical Industry Co., Ltd. Styron, glass transition temperature 100 ° C, SB: Clayton D-2401 manufactured by Shell Chemical Co., Ltd.
P, butadiene content = 25% by weight, MFR = 11
g / 10 minutes (200 ° C, load = 5kg)

(Production of polyester-based oxygen-scavenging resin)
In the present invention, in all the examples, a co-directional two-wheel extruder manufactured by Toshiba Machine Co., Ltd. (TEM37BS, 37 mm
(φ, L / D = 45) was used to produce an oxygen-scavenging resin.

1) Block copolymer [Polyester-based oxygen-scavenging resin- (PE-)] P
EN (Nihon Unipet Co., Ltd., Unipet NS76
3, intrinsic viscosity IV = 0.70) and 96 parts by weight were introduced from a hopper. The resin temperature was set to 290 ° C., and both ends of the hydroxyl group butadiene oligomer (ELF Atochem RHT)
45, Mw = 2800) A mixture of 4 parts by weight of a liquid material and 200 ppm of cobalt stearate with respect to the total amount of PEN and a hydroxyl group-containing butadiene oligomer at both ends was introduced into an extruder using a liquid injector. , Residence time about 5
After melt-kneading for minutes and transesterification, unreacted substances and low molecular weight substances were removed from the vacuum vent. This was extruded and the molten strand was quenched in water to form pellets.
The treatment was performed under a nitrogen atmosphere until pellets were obtained from the molten strand. The pellets were sufficiently crystallized in a vacuum dryer at a temperature of 120 ° C. for 2 hours.
After drying for a time, it was confirmed that the water content was not more than 0.005% by weight, and used for subsequent molding.

[Polyester-based oxygen-scavenging resin- (P
E-)] 92 parts by weight of PEN (manufactured by Nippon Unipet Co., Ltd., Unipet NS763, Ultimate Mucin IV = 0.70) were introduced from a hopper. The resin temperature is set to 290 ° C., and an amount of 200 ppm of cobalt stearate based on the total amount of PEN and the hydroxyl group butadiene oligomer at 8 parts by weight of the liquid substance having both ends hydroxyl group butadiene oligomer (RML20, manufactured by Elphachem Chem, Mw = 1230) Into the extruder using a liquid injection machine,
After melt kneading for about 5 minutes and transesterification, unreacted substances and low molecular substances were removed from the vacuum vent. This was extruded and the molten strand was quenched in water to form pellets. The treatment was performed under a nitrogen atmosphere until pellets were obtained from the molten strand. Further, the pellet was sufficiently crystallized in a vacuum dryer at a temperature of 120 ° C. for 2 hours.
After drying at 50 ° C. for 4 hours, it was confirmed that the water content was 0.005% by weight or less, and used for subsequent molding.

[Polyester-based oxygen-scavenging resin- (P
E-)] 88 parts by weight of PENT8 (Unipet NS663, manufactured by Nippon Unipet Co., Ltd., intrinsic viscosity IV = 0.72) were introduced from a hopper. The resin temperature was set to 280 ° C., and both ends of the hydroxyl group octadiene oligomer (an octadiene oligomer was synthesized from octadiene by metathesis polymerization, and both ends were replaced with hydroxyl groups by hydrolysis. Mw = 2000) 12 parts by weight of liquid material A mixture of PENT8 and cobalt stearate in an amount of 200 ppm and an amount of 200 ppm in benzophenone based on the total amount of the oligomers of PENT8 and hydroxyl groups at both ends was introduced into an extruder using a liquid injector, and the residence time was about After melt kneading for 5 minutes and transesterification, unreacted substances and low molecular substances were removed from the vacuum vent. This was extruded and the molten strand was quenched in water to form pellets. The treatment was performed under a nitrogen atmosphere until pellets were obtained from the molten strand. The pellets are further dried in a vacuum dryer at a temperature of 12 ° C.
After sufficiently crystallizing at 0 ° C. for 2 hours, it was dried at 150 ° C. for 4 hours. After confirming that the water content was 0.005% by weight or less, it was used for the subsequent molding.

2) Graft copolymer [Polyester-based oxygen-scavenging resin- (PE-)] P
EN (Nihon Unipet Co., Ltd., Unipet NS76
3, intrinsic viscosity IV = 0.70) 96 parts by weight were introduced from a hopper. Set the resin temperature to 290 ° C,
Butadiene oligomer having two hydroxyl groups (butadiene is subjected to ordinary anionic living polymerization, and by using ebichlorohydrin for termination reaction and further hydrolyzing,
A butadiene oligomer having two hydroxyl groups at one end was obtained. This time, the one with a molecular weight of 5000 was prepared. 4) Cobalt stearate was added to 4 parts by weight of the liquid material based on the total amount of PEN and two hydroxyl-butadiene oligomers at one end.
The mixture having an amount of 00 ppm was introduced into an extruder using a liquid injector, melt-kneaded for a residence time of about 5 minutes, transesterified, and then unreacted substances and low molecular substances were removed from a vacuum vent. This was extruded, and the molten strand was quenched in water and cut to obtain pellets. The treatment was performed under a nitrogen atmosphere until pellets were obtained from the molten strand. Further, the pellets were sufficiently crystallized at a temperature of 120 ° C. for 2 hours in a vacuum dryer, and then dried at 150 ° C. for 4 hours.
After confirming that the water content was 0.005% by weight or less, it was used for subsequent molding.

[Polyester-based oxygen-scavenging resin- (P
E-)] 99 parts by weight of PEN (manufactured by Nippon Unipet Co., Ltd., Unipet NS763, intrinsic viscosity IV = 0.70) and 1 part by weight of glycerin were added at 290 ° C.
To obtain modified PEN pellets. This modified PEN was used in the following reactions.

92 parts by weight of the above-mentioned modified PEN were introduced from a hopper. The resin temperature was set to 290 ° C., butadiene oligomer having one end terminal epoxy group (butadiene was subjected to ordinary anionic living polymerization, and epichlorohydrin was used for termination reaction to obtain a butadiene oligomer having one terminal epoxy group. A mixture of 4 parts by weight of the above-mentioned modified PEN and cobalt stearate in an amount of 200 ppm based on the total amount of the one-terminal epoxy group butadiene oligomer was introduced into an extruder, and the residence time was about 5 minutes. After melt-kneading and transesterification, unreacted substances and low molecular substances were removed from the vacuum vent. This was extruded, and the molten strand was quenched and cut in water to form pellets. The treatment was performed under a nitrogen atmosphere until pellets were obtained from the molten strand. Further, the pellets were sufficiently crystallized in a vacuum dryer at a temperature of 120 ° C. for 2 hours, then dried at 150 ° C. for 4 hours, and confirmed to have a water content of 0.005% by weight or less, and used for subsequent molding. did.

[Polyester-based oxygen-scavenging resin- (P
E-)] 88 parts by weight of PENT8 (Unipet NS663, manufactured by Nippon Unipet Co., Ltd., intrinsic viscosity IV = 0.72) were introduced from a hopper. The resin temperature was set to 280 ° C., and a norbornene oligomer having two hydroxyl groups at one end (a norbornene oligomer was synthesized by the above-described metathesis polymerization, and then one end was modified to two hydroxyl groups. This time, a molecular weight of 10,000 I made something.) 12
200 parts by weight of cobalt stearate based on the total amount of two hydroxyl norbornene oligomers at one end in parts by weight
Is introduced into the extruded weave from the second supply port into the extruded weave through the second supply port (different from the hopper of PENT8, it is preferable to introduce the norbornene oligomer through the second supply port after PENT8 is melted. It may be introduced from a hopper), melt-kneaded for a residence time of about 5 minutes, and transesterified, and then unreacted substances and low-molecular substances were removed from the vacuum vent. This was extruded and the molten strand was quenched in water to form pellets. The treatment was performed under a nitrogen atmosphere until pellets were obtained from the molten strand. Further, the pellets were sufficiently crystallized at a temperature of 120 ° C. for 2 hours in a vacuum dryer, and then dried at 150 ° C. for 4 hours.
After confirming that the water content was 0.005% by weight or less, it was used for subsequent molding.

(Production of polyamide-based oxygen-scavenging resin) 1) Block copolymer [Polyamide-based oxygen-scavenging resin- (PA-)] amorphous polyamide = TR55 (manufactured by EMS Co., Ltd .; Grillamide TR55, glass transition) 88 parts by weight were introduced from a hopper. The resin temperature was set to 290 ° C., and a normal anionic living polymerization was carried out using a butadiene oligomer having a carboxyl group at both terminals (butadiene was used. Initiator α-methylstyrene was used, and carbon dioxide gas was used in the termination reaction.This time, the molecular weight was 2,000.) TR5 was added to 12 parts by weight of the liquid material.
5 and a mixture of cobalt stearate in an amount of 200 ppm with respect to the total amount of the carboxyl group butadiene oligomers at both ends were introduced into an extruder using a liquid injector, and the mixture was melt-kneaded for a residence time of about 5 minutes. After removing unreacted substances and low molecular substances from the vacuum vent, the molten strand was quenched in water to obtain pellets. The treatment was performed under a nitrogen atmosphere until pellets were obtained from the molten strand. The pellets were dried in a vacuum dryer at a temperature of 120 ° C. for 4 hours, and it was confirmed that the water content was 0.05% by weight or less.
Modified grill amide TR55 produced as described above during molding
Was dry-blended with 50% by weight of Glyamide TR55.

[Polyamide-based oxygen-scavenging resin- (PA
-)] 96 parts by weight of amorphous polyamide = TR55 were introduced from a hopper. The resin temperature was set to 290 ° C., and a dicyclopentadiene oligomer having amino groups at both terminals was used (a dicyclopentadiene oligomer was synthesized by the above-described metathesis polymerization, and both terminal groups were substituted with amino groups. This molecular weight was used). 1000) A liquid material was mixed with an amount of 200 ppm of cobalt stearate based on the total amount of TR55 and dicyclopentadiene oligomers at both terminal amino groups, and the mixture was introduced into an extruder using a liquid injector, Unreacted substances and low molecular weight substances were removed from the vacuum vent by melt-kneading for a residence time of about 5 minutes, and then the molten strand was quenched in water to obtain pellets. The treatment was performed under a nitrogen atmosphere until pellets were obtained from the molten strand. Further, the pellets were dried in a vacuum dryer at a temperature of 120 ° C. for 4 hours, and confirmed that the water content was 0.05% by weight or less.
It was used for subsequent molding.

2) Graft copolymer [Polyamide-based oxygen-scavenging resin- (PA-)] A non-crystalline polyamide obtained by adding 1 part by weight of diethylenetriamine to 99 parts by weight of TR55 is melt-kneaded at 290 ° C. To obtain a modified grillamide TR55 pellet. This modified grillamide TR55 was used in the following reactions.

92 parts by weight of the above-mentioned modified grillamide TR55 were introduced from a hopper. The resin temperature was set at 290 ° C., butadiene oligomer having one terminal epoxy group (butadiene was subjected to ordinary anionic living polymerization, and shrimp globulin hydrin was used for the termination reaction to obtain a butadiene oligomer having one terminal epoxy group. Molecular weight 2000
Created. ) A mixture of 8 parts by weight of liquid material and 200 ppm of cobalt stearate with respect to the total amount of one-terminal epoxy group butadiene oligomer was introduced into an extruder using a liquid injector, and the residence time was about 5 minutes. After melt-kneading and removing unreacted substances and low molecular substances from the vacuum vent, the molten strand was quenched in water to obtain pellets. Until a pellet was obtained from the molten strand, the embedding was performed under a nitrogen atmosphere. Further, the pellets were dried in a vacuum dryer at a temperature of 120 ° C. for 4 hours to obtain a moisture content of 0.05% by weight.
After confirming the following, it was used for the subsequent molding.

[Polycarbonate oxygen scavenging resin-
(PC−)] polycarbonate = PC (Mitsubishi Gas Chemical Co., Ltd., Iupilon S2000, glass transition temperature 15)
(0 ° C.) 96 parts by weight were introduced from a hopper. A resin temperature is set to 280 ° C., and a butadiene oligomer having a carboxyl group at both ends (butadiene is subjected to ordinary anionic living polymerization, and a bifunctional initiator having two anion ends as an initiator to obtain carboxyl groups at both ends) Α-methylstyrene was used as an agent, and carbon dioxide gas was used in the termination reaction.This time, a product having a molecular weight of 2,000 was prepared.) A mixture obtained by mixing cobalt acid in an amount of 200 ppm was introduced into an extruder, and the mixture was melt-kneaded for a residence time of about 5 minutes to obtain an unreacted material.
After the low-molecular substances were removed from the vacuum vent, the molten strand was quenched in water and cut to obtain pellets. The treatment was performed under a nitrogen atmosphere until pellets were obtained from the molten strand. Further, the pellets are dried in a vacuum dryer at a temperature of 120 ° C.
For 4 hours, and it was confirmed that the water content was 0.05% by weight or less.

[Polycarbonate oxygen scavenging resin-
(PC−)] polycarbonate = PC (Mitsubishi Gas Chemical Co., Ltd., Iupilon S2000, glass transition temperature 15)
(0 ° C.) A mixture of 99 parts by weight and 1 part by weight of glycerin was melt-kneaded at 280 ° C. to obtain modified PC pellets.
Next, 92 parts by weight of the modified PC was introduced from a hopper. A resin temperature was set to 280 ° C., and a butadiene oligomer having an epoxy group at one end (butadiene was subjected to ordinary anionic living polymerization, and epichlorohydrin was used for termination reaction to obtain a butadiene oligomer having an epoxy group at one end. Was prepared with a molecular weight of 10,000.) A mixture of 8 parts by weight of the liquid material and 200 ppm of cobalt stearate based on the total amount of the modified PC and the one-terminal epoxy group butadiene oligomer was mixed using a liquid injector. It is introduced into the extruder (different from the hopper of PC, it is preferable that PC is introduced from the second supply port after melting, but it may be dry-blended with PC and introduced from the hopper), and the residence time is about Melt and knead for 5 minutes,
After unreacted substances and low molecular substances were removed from the vacuum vent, the molten strand was quenched in water and cut to obtain pellets.
The treatment was performed under a nitrogen atmosphere until pellets were obtained from the molten strand. The pellets were further dried in a vacuum drier at a temperature of 120 ° C. for 4 hours, and confirmed to have a water content of 0.05% by weight or less, and used for subsequent molding.

[Polyarylate-based oxygen-scavenging resin-
(PAR-)] polyarylate (manufactured by Unitika Ltd.)
U polymer U-100, glass transition temperature 193 ° C)
Introduced from 6 parts by weight hopper. The resin temperature was set to 320 ° C., and a dicyclopentadiene oligomer having amino groups at both ends (a dicyclopentadiene oligomer synthesized by the above-described metathesis polymerization and both ends were substituted with amino groups was used. A mixture of 4 parts by weight of the liquid material and 200 ppm of cobalt stearate based on the total amount of the PAR and the dicyclopentadiene oligomer having amino groups at both terminals was extruded using a liquid injector. And a residence time of about 5
After melt kneading for 1 minute, unreacted substances and low molecular substances were removed from the vacuum vent, and the molten strand was quenched in water to obtain pellets. The treatment was performed under a nitrogen atmosphere until pellets were obtained from the molten strand. The pellets were further dried in a vacuum dryer at a temperature of 120 ° C. for 4 hours, and were confirmed to have a water content of 0.05% by weight or less, and were used for subsequent molding.

(Production of polystyrene-based oxygen-scavenging resin) [Polystyrene-based oxygen-scavenging resin- (PS-)] 50 parts by weight of polystyrene (Stylon, glass transition temperature 100 ° C, manufactured by Asahi Kasei Corporation) and styrene-butadiene Resin (Clayton D-1401 manufactured by Shell Chemical Co., Ltd.)
50 parts by weight of P) and 200 ppm of cobalt stearate based on the total amount thereof were dry-blended, and the mixture was introduced from a hopper. The resin temperature was set at 240 ° C. to obtain pellets. Table 1 summarizes the results of the production of the above oxygen-supplementing resin.

[0062]

[Table 1]

(Transparent resin for inner and outer layers) Transparent polypropylene = transparent PP (random PP) Nippon Polyolefin Co., Ltd., PM620A, density =
0.9 g / cm ³ , MFR = 7.0 g / 10 min. Polymethylpentene, manufactured by Mitsui Chemicals, Inc., TPX. DX810. Alicyclic polyolefin manufactured by Nippon Zeon Co., Ltd., Zeonor 1420R, MFR = 2
0 (280 ° C., 2.16 kg) polyethylene naphthalate (PEN) manufactured by Nippon Unipet Co., Ltd., Unipet NS763: intrinsic viscosity IV = 0.70

Polyethylene naphthalate: PENT8 Nippon Unipet Co., Ltd., Unipet NS663: Intrinsic viscosity IV = 0.72 PEN: PET = 92 mol%: 8 mol% Polyamide: Trogamide T Dynamit Nobel, Trogamide T, glass Transition temperature 148 ° C. Constituent monomer: trimethyl-1,6-hexamethylenediamine, terephthalic acid polyamide: GRILLAMID TR
55 (TR55), manufactured by EMS, Grilamid TR55, glass transition temperature = 160 ° C. Constituent monomers: isophthalic acid, 4,4′-diamino-
3,3'-dimethyldicyclohexylenemethane, laurolactam polystyrene (PS) Asahi Kasei Corporation, Styron

(Examples 1 to 13) Table 2 shows the resin composition of each layer of the laminated body having the basic structure of the inner resin layer / oxygen supplementing resin layer / outer resin layer and the thickness of each layer. In Examples 10 to 13 and Comparative Examples 10 to 13, those obtained by adding 0.15% by weight of a UV absorber (Tinuvin 326: manufactured by Ciba Specialty Chemicals) to the outer layer resin were used. The sheet (film) of each layer was dry-laminated using a urethane-based adhesive. The obtained laminate (multilayer sheet) was vacuum-formed at the temperatures shown in Table 2 to form a nearly cylindrical container having a maximum diameter of 7 cm and a volume of about 80 cc.

[0066]

[Table 2] * 1: Transparent PP = PM620A (Japan Polyolefin Co., Ltd.) * 2: Cyclic PO = Zeonor 1420R (Nippon Zeon Co., Ltd.) * 3: T = Trogamid (Dynamit Nob)
el)

(Comparative Examples 1 to 13) Vacuum forming was performed at the temperature shown in Table 3 in the same manner as in Example except that the resin of the oxygen-supplementing resin layer in Example was changed to the resin film shown in Table 2.
An almost cylindrical container having a maximum diameter of 7 cm and a volume of about 80 cc was formed.

[0068]

[Table 3]

(Evaluation method) 1) Oxygen permeability The oxygen permeability was OX-TRAN2 / 20M manufactured by Mocon.
L-measured. The measurement condition is that the inner surface is 65% at 25 ° C.
RH.

2) Change in Oxygen Concentration in Container Change in Oxygen Concentration in Nitrogen Gas Replacement Container The laminate containers prepared in Examples and Comparative Examples were filled with nitrogen gas at normal pressure, and an aluminum foil resin laminate was used. Sealed by heat sealing. The oxygen concentration in these containers was measured over time. Oxygen concentration at start is 0.7
It was 0%. Change in Oxygen Concentration in Container after Air Sealing The laminate containers prepared in Examples and Comparative Examples were filled with air at normal pressure, and sealed by heat sealing using an aluminum foil resin laminate. The oxygen concentration in these containers was measured over time. Oxygen concentration at start is 21.0%
Met.

3) Evaluation of suitability for retort Into the laminated containers prepared in Examples and Comparative Examples, 70 cc of distilled water was placed, and a resin capable of being heat-sealed to various containers in aluminum foil (20 μm) (the same composition as the inner layer of the container)
Was heat-sealed with a laminated lid material. This distilled water-filled container was placed in a 120-liter container using a normal retort sterilizer.
The mixture was subjected to retort sterilization at 30 ° C. for 30 minutes. A change in transparency and a change in container size before and after the retort treatment were measured, but no change was observed.

4) Microwave oven suitability test 70 ml of distilled water was put into the laminate containers prepared in Examples and Comparative Examples, and Saran wrap (Asahi Kasei Co., Ltd .: PVD)
C) and placed in the microwave. When heated at 600 W for 1 minute, it immediately boiled. This container was measured for change in transparency and change in dimensions, and no change was observed.

5) Evaluation of UV-cutting property The bottom of the container was sampled (1 cm × 1 cm), and the wavelength was 300 to 4 using a Hitachi spectrophotometer (U-3010).
The light transmittance (%) at 00 nm was measured. Ultraviolet rays (300 to 400 nm) were cut in all of the examples and comparative examples. Tables 4 and 5 show the evaluation results of the changes in the oxygen permeability and the oxygen concentration in the containers produced in the examples and the comparative examples and the containers produced therefrom.

[0074]

[Table 4]

[0075]

[Table 5]

[0076]

The multilayer molded container of the present invention has a transparent thermoplastic resin layer / a resin layer containing an oxygen-scavenging resin / a transparent thermoplastic resin layer laminated in this order from the inside, and has an oxygen barrier on the container wall. In addition to the plastic container, the wall is a plastic multilayer container capable of trapping and eliminating oxygen inside the multilayer container. In particular, since oxygen scavenging is performed over the entire wall surface of the multilayer molded container, when compared with the conventional oxygen-resistant multilayer molded container in which the oxygen absorber is enclosed, deoxidation is not localized but over the entire multilayer molded container. An effect to be performed uniformly is exhibited. Further, in the case of a multilayer molded container in which a transparent thermoplastic resin layer / oxygen supplementing resin layer / transparent gas barrier resin layer / transparent thermoplastic resin layer are laminated in this order, it is only necessary to eliminate oxygen inside the multilayer molded container. Therefore, since the amount of oxygen gas permeating from the outside can be greatly reduced, the effectiveness retention period increases even if the oxygen capturing capacity of the multilayer molded container is the same, and the long-term presence of oxygen inside the plastic multilayer molded container Time of zero amount can be secured. In addition to not only having high oxygen barrier properties without the need for aluminum foil, there is no problem in incineration. In particular, the multilayer molded container has a long shelf life because there is no influence of oxygen on the contents, does not use an oxygen scavenger, so there is no need for moisture inside the container, and there is no need for a nitrogen gas atmosphere when filling. In addition to such features, it can sterilize retort required for foods, especially cooked foods, etc.It also has the feature that microwave lid cooking adaptability is also possible by removing the lid This is a multilayer molded container having excellent features not found in plastic multilayer molded containers for food packaging.

 ────────────────────────────────────────────────── ─── Continuing from the front page (72) Inventor Tomohiko Miyauchi 1-13-9 Shiba-Daimon, Minato-ku, Tokyo F-term in Showa Denko KK (reference) 3E033 BA14 BA15 BA16 BA17 BA18 BA19 BA21 BA22 BB01 BB08 CA03 CA07 CA16 CA18 FA02 FA03 FA04 GA01 GA02 3E067 AA03 AA05 AB23 AB26 BA01A BB14A BB15A BB16A CA06 CA11 CA17 GA11 GA20 GD02 4F100 AK01A AK01B AK02C AK03C AK07C AK12C AK27C AK41C AK42C AK42J AK43C AK43J AK45C AK46C AK80C AL01C BA03 BA06 BA10A BA10B BA15 DA01 GB16 JA03 JA12C JB16A JB16B JD09 JJ03 JL04 JN01 JN01A JN01B JN01C

Claims (8)

[Claims] The layer structure from the inner layer to the outer layer is laminated in the order of a transparent thermoplastic resin layer / a resin layer containing an oxygen-capturing resin / a transparent thermoplastic resin layer. A transparent plastic multilayer molded container manufactured by pressure molding, blow molding or injection molding. 2. The method according to claim 1, wherein the oxygen-scavenging resin is a transparent polyester, polyamide, polyolefin or vinyl polymer having a polyolefin segment having a carbon-carbon unsaturated bond in the molecule. The transparent plastic multilayer molded container according to the above. 3. The method according to claim 1, wherein the oxygen-scavenging resin is 1 to 15% by weight.
The transparent plastic multilayer according to claim 1 or 2, which is a polymer comprising a polyolefin oligomer segment having a carbon-carbon unsaturated bond and 85 to 99% by weight of a main polymer segment, and containing 50 to 500 ppm of a transition metal compound as a metal atom. Molded container. 4. The transparent plastic multilayer molded container according to claim 2, wherein a photo-oxidation accelerator having a sensitizing effect on ultraviolet light and / or visible light is added to the oxygen-scavenging resin layer. 5. The polyolefin oligomer segment in the oxygen-scavenging resin is an oligomer segment having a molecular weight of 1,000 to 10,000, including one of polymerized oligomer units of butadiene, norbornene, dicyclopentadiene, and isoprene. Item 2
5. The transparent plastic multilayer molded container according to any one of items 4 to 4. 6. The oxygen-scavenging resin in which the polyolefin oligomer segment having a carbon-carbon unsaturated bond in the oxygen-scavenging resin is bonded as a main chain of a main polymer segment or as a branch pendant.
6. The transparent plastic multilayer molded container according to any one of items 5 to 5. 7. The transparent thermoplastic resin is made of polyethylene naphthalate, polyarylate, transparent polypropylene, cyclic polyolefin, amorphous polyamide, polymethylpentene-1, polystyrene, transparent polyethylene terephthalate resin, polycarbonate and polyacrylonitrile. 6. A resin selected from the group consisting of:
The transparent plastic multilayer molded container according to any one of the above. 8. The polyethylene naphthalate resin is a copolymer containing at least 80% by weight of a polyethylene naphthalate component, and the polyarylate resin is a copolymer containing at least 80% by weight of a polyarylate component or a blend thereof. The transparent plastic multilayer molded container according to claim 7, which is a resin.