JP2007016117A - RESIN COMPOSITION HAVING OXYGEN ABSORPTION AND LAMINATE AND PACKAGE CONTAINING RESIN COMPOSITION LAYER - Google Patents

Abstract

The present invention provides a trigger function for starting oxygen absorption by heat, ultraviolet light (UV), etc., quick response to start oxygen absorption quickly by trigger, and reducing odor generated after oxygen absorption. Provided are a resin composition having an oxygen absorption ability, a laminate and a package including the resin composition layer, which are excellent in stability and safety.
A thermoplastic resin (resin A), a thermoplastic resin having an ethylenically unsaturated bond (resin B), a thermoplastic resin (resin C) having the effect of a compatibilizer between resin A and resin B, and an oxidation catalyst A resin composition comprising a low-molecular oxidizable compound, wherein the resin A comprises 50 to 99 wt%, and the resin obtained by mixing the resin B and the resin C comprises 1 to 50 wt%, A resin composition having an oxygen absorption capacity, characterized in that an oxidation catalyst is blended in an amount of 0.001 to 2% with respect to the resin B and a low-molecular oxidizable compound is blended in an amount of 0.1 to 20% with respect to the resin B A laminate and a package including the composition layer.
[Selection] Figure 5

Description

  The present invention relates to a resin composition having oxygen-absorbing ability, and a laminate and a package including the resin composition layer, and more specifically, oxygen absorption is rapidly performed using active energy rays such as heat and ultraviolet rays (UV) as a trigger. The present invention relates to a resin composition having an oxygen-absorbing ability capable of reducing odor, which has been considered as a problem in conventional polymer oxygen absorbers, and a laminate and a package including the resin composition layer.

In the field of packaging business for packaging various contents, the keywords of “package” or “packaging” can include the following contents.
(1) “Display effects” such as giving consumers purchase awareness and presenting dangers
(2) “Content resistance” to prevent the package from being attacked by the filled contents themselves
(3) “Protection of contents” against external stimuli

  These keywords are further subdivided and expanded to fine required quality. Among them, the protection of contents from oxygen and moisture is particularly attracting attention in terms of “protection of contents”. In recent years, in particular, in the fields of food, industrial products, medical / pharmaceutical fields, etc., the protection of contents against oxygen and moisture has been regarded as important. As the background, there are oxygen content decomposition and alteration due to oxidation, and moisture content alteration due to moisture absorption and hydrolysis.

  Thus, various methods have been studied in order to prevent alteration of contents due to oxygen or moisture. One of them is to design a package using a material having an oxygen barrier or moisture barrier property. For example, in terms of oxygen barrier, a laminate using a thermoplastic resin having excellent oxygen gas barrier properties such as an ethylene-vinyl alcohol copolymer, and a vapor deposition layer such as aluminum vapor deposition, silica vapor deposition, and alumina vapor deposition are polyester. The laminated body using the vapor deposition film obtained by providing in a base material etc. is mentioned.

  The packaging body using these barrier substrates is spreading to various uses because of its high oxygen barrier property. However, although these barrier substrates are said to have a high barrier property, they pass a very small amount of oxygen. In addition, when these packages are used to fill the contents, headspace gas is almost always present. Recently, attempts have been made to remove oxygen in the headspace by performing inert gas replacement, since oxygen remaining in the headspace also deteriorates the contents, but a small amount of oxygen still remains. The situation remains.

As described above, an oxygen-absorbing resin composition has been developed in order to remove a small amount of oxygen passing through the barrier base material or oxygen in the head space gas inside the package. Among these, the most typical types are as follows.
(1) Type in which reduced iron is blended with thermoplastic resin (2) Oxygen coordination bond type using transition metal complex (3) Hydrogen peroxide (other gases using reduction / oxidation reaction of reducible compound) Conversion)
(4) A type using oxidative decomposition or oxygen addition reaction of a thermoplastic resin having a carbon-carbon double bond.

First, typical (1) “type in which reduced iron is blended with thermoplastic resin” as an oxygen-absorbing wrapping material is a conventional oxygen scavenger concept. When reduced iron undergoes an oxidation reaction to iron oxide, oxygen Is used to consume. The amount of oxygen consumed along with the oxidation is extremely large, and a resin composition that is very effective in terms of oxygen absorption capacity is developed by blending with a thermoplastic resin. However, “Transparency as a resin composition is low”, “Dispersion of reduced iron into resin and appearance deterioration due to browning due to oxidation”, “Since moisture is a trigger, content with high water activity Can only be applied to products "," Some odors are emitted depending on the contents to be stored "," Crystal structure changes due to the reaction from reduced iron to iron oxide, and the packaging material breaks down and the composition in the composition is eluted. ”(See Patent Document 1).

The “oxygen coordination bond type using a transition metal complex” in (2) has a very low ability to coordinate one molecule of oxygen to one molecule of transition metal in the complex, and is accompanied by oxygen coordination. Although it functions as an indicator from the change in color tone, it is extremely difficult to develop as an oxygen absorber (see Patent Documents 2 and 3).
With regard to (3) “hydrogenation using a reduction / oxidation reaction of a compound to be reduced”, since hydrogen peroxide is generated after oxygen absorption, there is a problem in hygiene / safety. Another problem is that the thermoplastic resin itself is discolored (also functions as a pigment) by using this reaction (see Patent Document 4).

  From this point of view, (4) “type using oxidative decomposition or oxygen addition reaction of thermoplastic resin having carbon-carbon double bond” has been actively studied. This application also belongs to this type. Although this type of problem is excellent in oxygen absorption capacity, the generation of odor accompanying oxidation reaction and the deterioration of film physical properties are cited as problems (see Patent Documents 5 and 6). In these patent documents, auto-oxidation of a thermoplastic resin having a carbon-carbon double bond is promoted by an oxidation catalyst, and oxygen can be absorbed, but its control is difficult. (Because the trigger function is not clear, oxygen absorption starts anytime). In order to improve such a problem, a trigger system for starting oxygen absorption using an active energy ray such as UV has been proposed (Patent Document 7). By using this system, the absorption of oxygen is usually started by suppressing auto-oxidation of a thermoplastic resin having a carbon-carbon double bond with an antioxidant or the like and irradiating with an active energy ray such as UV. It became possible to clarify the trigger function. However, this method requires blending of components such as photosensitizers, and there remains a problem in safety and hygiene such as elution of these components. In addition, in order to clarify this trigger function, it is necessary to suppress the auto-oxidation of the thermoplastic resin using an antioxidant. On the other hand, it is difficult to develop a trigger function for oxygen absorption due to heat and the like. It has the problem of being. This means that it cannot be applied to packaging materials that are difficult to be irradiated with active energy rays such as UV, such as boil and retort packaging materials. The present inventors have also studied the improvement of the oxygen absorption capacity and speed of the UV-triggered oxygen absorber using a readily oxidizable thermoplastic resin having a carbon-carbon double bond, and good results have been obtained. However, although the possibility in terms of thermal triggering was found, the effect is insufficient, and at the same time, it contains a photosensitizer that requires a problem in the safety of the eluate. Improvement was required (see Patent Document 8).

  The contents described above relate to the provision of a trigger for oxygen absorption, but it is essential to improve the odor generated with oxygen absorption. In order to improve the odor, many of them are mainly studied by adding a deodorant. However, the amount of odor generated due to oxygen absorption is very large (that is, the decomposition reaction accompanying oxidation reaction is remarkable), and no matter how much deodorant is added, the odor cannot be completely removed (patents) Reference 9).

In the resin composition consisting of thermoplastic resin (matrix phase) and oxygen-absorbing resin (domain phase), there are literatures on the content of whether the mixing part of the oxidation catalyst is on the matrix phase side or on the domain phase side (patent) Reference 10). However, in this resin composition, it is for examining the blending site of the oxidation catalyst so as not to oxidize the oxygen-absorbing resin that is easily oxidized during the processing process, and not for the purpose of expressing the oxygen-absorbing ability. Absent.

Thus, the appearance of oxygen-absorbing resins is an area that is expected in terms of the effect of preserving the contents of future packages, but considering the development of packaging, there are still many improvements to be made. The issues to be improved are listed below.
(1) Addition of a trigger function that starts oxygen absorption by heat, ultraviolet rays (UV), etc. (expands the range of oxygen absorbing packaging materials)
(2) Speed of response to start oxygen absorption quickly when a trigger is given (coexistence of oxygen absorption amount and oxygen absorption rate as an oxygen-absorbing packaging material)
(3) Clarification of trigger function (for example, storage stability as an oxygen-absorbing wrapping material that is stable at room temperature but absorbs oxygen after applying the trigger, and compatibility of the functions (1) and (2) above)
(4) Reduction of odor (reduction of odor generated after oxygen absorption)
(5) Addition of safety (no elution photosensitizer is used)

Patent documents are described below.
Japanese Patent No. 3019153 Japanese Patent Publication No. 7-82001 Japanese Patent No. 2803508 Japanese Patent No. 2922306 Japanese Patent No. 3183704 Japanese Patent No. 3064420 Japanese Patent No. 3202026 WO2004 / 018564 Special table 2002-504159 gazette Japanese Patent No. 3429773

  The present invention has been made in consideration of the above technical background, and provides a trigger function for starting oxygen absorption by heat, ultraviolet rays (UV), etc., and quickly absorbs oxygen when a trigger is given. Provided are a resin composition having a fast response, a reduced odor generated after oxygen absorption, excellent storage stability and safety, oxygen absorption ability, and a laminate and a package including the resin composition layer For the purpose.

In order to achieve the above object, that is, the invention described in claim 1 includes a thermoplastic resin (resin A), a thermoplastic resin having an ethylenically unsaturated bond (resin B), and a compatibilizing agent for resin A and resin B. Thermoplastic resin (Resin C)
A resin composition comprising an oxidation catalyst and a low-molecular oxidizable compound,
The resin A is 50 to 99 wt%, the resin B and the resin C are mixed 1 to 50 wt%, and the oxidation catalyst is 0.001 to 2% with respect to the resin B. An easily oxidizable compound is blended in an amount of 0.1 to 20% with respect to the resin B.

The invention according to claim 2 is characterized in that the resin B comprises a unit (resin B-1) composed of a compound having a glass transition temperature (Tg) ≧ 50 ° C. and a unit composed of a compound having an ethylenically unsaturated bond (resin B-2). ) Block copolymer,
The resin composition having an oxygen absorption capacity according to claim 1, wherein the resin B-1 is 50 to 99 wt% and the resin B-2 is 1 to 50 wt%.

  According to a third aspect of the present invention, the resin B-1 is selected from one or more of polystyrene, poly (meth) acrylic acid, polyacrylonitrile, or derivatives thereof, and the resin B-2 is polybutadiene, polyisoprene, or The resin composition having oxygen absorbing ability according to claim 2, wherein at least one of these derivatives is selected.

The invention according to claim 4 is a graft copolymer in which the resin C is grafted with a unit composed of the resin B-1 on the resin A,
The resin composition having an oxygen absorption capacity according to any one of claims 1 to 3, wherein the resin A is 50 to 99 wt% and the resin B-1 is 1 to 50 wt%.

  The invention according to claim 5 is the resin composition having an oxygen absorption capacity according to any one of claims 1 to 3, wherein the resin C is a hydrogenated product of the resin B. .

  In the invention according to claim 6, the dispersion state of the resin composition comprising the resin A, the resin B, and the resin C has a structure in which the dispersed phase (α) in which the resin B is dispersed in the resin C is further dispersed in the resin A. It is a resin composition which has oxygen absorption ability of any one of Claims 1-5 characterized by the above-mentioned.

  The resin B-2 unit of the resin B in the dispersed phase (α) in which the resin B is dispersed in the resin C is the resin B-1 unit of the resin B and the resin B-1 unit of the resin C. 7. The structure according to claim 6, wherein the outer shell of the resin B-1 is coated with the resin A unit of the resin C. It is the resin composition which has the oxygen absorption capability of description.

  The invention according to claim 8 is characterized in that the oxidation catalyst and the low molecular oxidizable compound are present at least in the dispersed phase (α). It is a resin composition having oxygen absorbing ability.

  The invention according to claim 9 is a transition metal compound such as an aromatic carboxylate, saturated or unsaturated carboxylate, wherein the oxidation catalyst is selected from one or more of cobalt, manganese, iron, nickel, copper, cerium and the like 9. The resin composition having oxygen-absorbing ability according to claim 8, which is a salt or one or more compounds selected from various transition metal complexes such as acetylacetonate, ethylenediaminetetraacetic acid, salen, porphyrin, and phthalocyanine. It is a thing.

  The invention according to claim 10 is the resin composition having oxygen absorbing ability according to claim 8, wherein the low molecular oxidizable compound is a higher unsaturated fatty acid or a derivative thereof.

The invention according to claim 11 is the thermoplastic resin (resin A) is polyethylene, ethylene-α olefin copolymer, polypropylene, polybutene-1, poly-4-methylpentene-1, ethylene-propylene random copolymer, Polyolefin resins such as propylene-ethylene random copolymer, propylene-ethylene block copolymer, ethylene-propylene-polybutene-1 copolymer, ethylene-cycloolefin copolymer, ethylene-α, β unsaturated carboxylic acid or the like An esterified product, an ionic cross-linked product thereof, an ethylene-vinyl acetate copolymer, an ethylene copolymer represented by a partially saponified product or a completely saponified product thereof, or a graft-modified polyolefin resin, or a mixture of one or more of these. Claim, characterized in that A resin composition having oxygen absorbing ability according to any one of 1 to 10.

  A twelfth aspect of the present invention is a laminate including at least the resin composition layer having an oxygen absorption capacity according to any one of the first to eleventh aspects.

  A thirteenth aspect of the present invention is the laminate according to the twelfth aspect, wherein the thickness of the resin composition layer is in the range of 5 to 200 μm.

The invention according to claim 14 is a thermoplastic resin layer having an oxygen permeability of 50 cm ³ or less under the condition of 25 μm (thickness) / m ² (area) / 24 h / (1.01325 × 10 ⁵ Pa) (pressure), The laminate according to claim 12 or 13, comprising at least one barrier layer selected from a metal foil layer, a metal-deposited thermoplastic polymer layer, and an inorganic compound-deposited thermoplastic polymer layer.

  In the invention described in claim 15, the thermoplastic resin layer as the barrier layer is selected from a polyester resin layer, a polyamide resin layer, a polyacrylonitrile layer, a polyvinyl alcohol layer, an ethylene-vinyl alcohol copolymer layer, and a polyvinylidene chloride layer. The laminate according to claim 14, wherein the laminate is a thermoplastic resin layer.

  The invention according to claim 16 is the laminate according to claim 14, wherein the metal foil layer is an aluminum foil.

  The invention according to claim 17 is the laminate according to claim 14, wherein the metal of the metal-deposited thermoplastic polymer layer is aluminum.

  The invention according to claim 18 is the laminate according to claim 14, wherein the inorganic compound of the inorganic compound vapor-deposited thermoplastic polymer layer is silica or alumina.

  A nineteenth aspect of the present invention is the laminate according to the twelfth or thirteenth aspect, wherein a deodorant is blended in the resin composition layer having oxygen absorbing ability.

  A twentieth aspect of the present invention is a package formed from the laminate according to any one of the twelfth to nineteenth aspects.

  The invention according to claim 21 is the package according to claim 20, characterized in that oxygen absorption is started by a temperature of at least 25 ° C. or higher or an active energy ray such as ultraviolet rays.

According to the present invention, the resin composition having oxygen absorbing ability gives a trigger function to start oxygen absorption by heat, ultraviolet rays (UV), etc. by controlling the morphology of its unique thermoplastic resin, If given, the resin composition has a quick response to start oxygen absorption quickly, reduces the odor generated after oxygen absorption, has excellent storage stability and safety at room temperature, and has an oxygen-absorbing ability and its resin composition A laminate and a package including a physical layer can be provided.

  Even in the case where a special filling line is required for the conventional UV trigger type, the resin composition having the oxygen absorption ability of the present invention can be designed not only for UV but also for a thermal trigger. is there. In addition, the temperature of the heat trigger can be controlled, and the heat during boil and retort sterilization can also be used as a trigger, so various oxygen absorbing packaging materials can be designed according to the trigger type (UV or heat). Is possible. Furthermore, since the odor accompanying oxygen absorption can be reduced by controlling the original morphology, it is possible to develop applications in a wide range.

Hereinafter, an embodiment of the present invention will be described in detail. The resin composition having oxygen-absorbing ability of the present invention has the effect of a thermoplastic resin (resin A), a thermoplastic resin having an ethylenically unsaturated bond (resin B), and a compatibilizer for resin A and resin B. In a resin composition comprising a thermoplastic resin (resin C), an oxidation catalyst, and a low-molecular oxidizable compound, resin A: 50 to 99 wt%, resin B + resin C: 1 to 50 wt%, and oxidation catalyst is 0 with respect to resin B 0.002 to 2%, comprising a resin composition having an oxygen absorption capacity and a resin composition layer thereof, wherein the low-molecular oxidizable compound is blended in an amount of 0.1 to 20% with respect to resin B By controlling the structure and dispersion state of each resin (A to C) of this resin composition, and further the dispersion position of the oxidation catalyst and the low-molecular oxidizable compound. , The following problems (1) to (5) It is that persists.
(1) Addition of trigger function to start oxygen absorption by heat, UV, etc. (2) When a trigger is given, response speed to start oxygen absorption quickly (3) Clarification of trigger function (example : Stable at room temperature, but oxygen absorption after triggering)
(4) Reduction of odor (5) Addition of safety

The thermoplastic resin (resin A) as the main component of the resin composition controls the moldability and strength properties of the oxygen-absorbing resin, and mainly includes polyolefin resins or ethylene copolymers. For example, low-density polyethylene, medium-density polyethylene, high-density polyethylene, α-olefin is an ethylene-α olefin copolymer such as butene-1, hexene-1, octene-1, 4-methylpentene-1, polypropylene, Polyα-olefins such as polybutene-1 and poly-4-methylpentene-1, α-olefin-ethylene copolymers such as random polypropylene and block polypropylene, or copolymers of two or more α-olefins such as ethylene-propylene -Butene copolymer, butene-propylene copolymer, propylene-butene-hexene copolymer and the like can also be used. A polyolefin resin such as an ethylene-cyclic olefin copolymer can also be used. Examples of the ethylene copolymer include ethylene- (meth) acrylic acid copolymer, ethylene-methyl (meth) acrylate, ethylene-ethyl (meth) acrylate, ethylene- (meth) acrylate n-butyl, ethylene -(Meth) acrylic acid i-butyl, ethylene- (meth) acrylic acid t-butyl, various ionic cross-linked products of ethylene- (meth) acrylic acid, ethylene- (meth) acrylic acid- (meth) acrylic acid ester ternary Ethylene-α, β unsaturated carboxylic acid such as copolymer or esterified product thereof, ionic cross-linked product thereof, ethylene-vinyl acetate copolymer or partially saponified product or completely saponified product thereof, ethylene-α, β unsaturated carboxylic acid Acid ester-maleic anhydride terpolymer, ethylene- (meth) acrylic acid glycidyl ester copolymer, etc. And the like. Further, graft modified polyolefin resins obtained by graft reaction of reactive functional groups such as maleic anhydride, vinyl, (meth) acryloxysilane compounds, and (meth) acrylic acid glycidyl esters can be mentioned. Further, if necessary, it may be a copolymer of various components, and may be variously selected such as a copolymer of carbon monoxide and an allyl compound. These polyolefins or ethylene copolymers can be used alone or as a mixture of one or more of them.

  The thermoplastic resin (resin B) having an ethylenically unsaturated bond is a phase contributing to oxygen absorption. The structure is a block copolymer of a unit (resin B-1) composed of a compound having a glass transition temperature (Tg) ≧ 50 ° C. and a unit (resin B-2) composed of a compound having an ethylenically unsaturated bond. The resin B-1 is preferably in the range of 50 to 99 wt% and the resin B-2 in the range of 1 to 50 wt%. As such a resin B-1, at least one selected from polystyrene, po-α-methylstyrene, polyvinyl naphthalene, poly (meth) acrylic acid, poly (meth) acrylic acid ester, polyacrylonitrile, or derivatives thereof is selected. The resin B-2 is selected from one or more compounds such as polybutadiene, polyisoprene, and poly-2-ethylbutadiene. Both resin B-1 and resin B-2 are not limited to these materials, and various types of compounds can be used. Examples include styrene-butadiene-styrene block copolymer, styrene-isoprene-styrene block copolymer, etc., and the structure of the block copolymer can be selected variously such as linear type and side chain type. Is possible. Furthermore, as an example of butadiene, various structural isomers such as a simple substance such as 1,2-butadiene, trans 1,4-butadiene, cis 1,4-butadiene, or a copolymer thereof can be used.

  Resin B-2 is a unit that further contributes to oxygen absorption among the resins B, and considering the reaction mechanism such as crosslinking / decomposition reaction accompanying oxidation, the unit is made of polybutadiene that is hardly oxidatively decomposed as much as possible among the various resins B-2 described above. Is preferable. Resin B-1 is a unit necessary for improving the workability of resin B-2, which is a thermoplastic rubber, and has a glass transition temperature (Tg) ≧ 50 ° C. It is possible to impart temperature dependence to the. Further, the glass transition temperature (Tg) being higher than room temperature means that the molecular motion of the resin B-1 is frozen at room temperature, so that it is possible to trap the odor generated by oxygen absorption. To do. Further, when the resin B-1 is polystyrene, it is still effective because it can contribute as an immobilized phase of a low molecular weight easily oxidizable compound described later. The blending ratio of the resins B-1 and B-2 contained in the resin B is resin B-1: 50 to 99 wt% from the relationship with processability, oxygen absorption capacity, or blending ratio with other components described later. Resin B-2: It is preferable that it is the range of 1-50 wt%. The respective effects of the resins B-1 and B-2 in the resin B will be described in detail in the section of morphology control.

  As a thermoplastic resin (resin C) having the effect of a compatibilizing agent for resin A and resin B, a graft copolymer in which “unit consisting of resin B-1” is grafted to “unit consisting of thermoplastic resin (resin A)”. It is a polymer, and the resin A unit and the resin B-1 unit in the resin C are resin A: 50 to 99 wt% and resin B-1: 1 to 50 wt%. Taking B-1 in resin A and resin B described above as an example, a thermoplastic resin such as polystyrene or poly (meth) acrylate is grafted to a polyolefin resin such as low-density polyethylene or polypropylene. Can be mentioned. In this case, if the resin B-1 is less than 1 wt%, it is difficult to obtain the effect of compatibilization with the resin B. When the amount is more than 50 wt%, the workability is lowered. Further, as a compatibilizing agent for resin A and resin B, a compound obtained by hydrogenating a thermoplastic resin (resin B) having an ethylenically unsaturated bond can be suitably used. Is a styrene-butadiene-styrene block copolymer, a styrene-ethylene-butylene-styrene copolymer, and a styrene-isoprene-styrene copolymer are styrene-ethylene-propylene-styrene copolymers. . The effects of using these resins C will be described later as in the case of the resins B.

  As an additive to be blended in the resin composition, a compound containing a transition metal is first mentioned. This compound containing a transition metal serves as a catalyst for an oxygen absorption mechanism. Examples of these transition metals include elements of periodic groups 3A to 7A, 8, and 1B, and among these, one or more compounds selected from cobalt, manganese, iron, nickel, copper, and cerium are particularly preferable. These transition metal compounds include transition metal compound salts such as aromatic carboxylates, saturated or unsaturated carboxylates, or various transition metal complexes such as acetylacetonate, ethylenediaminetetraacetic acid, salen, porphyrin, and phthalocyanine. Can be mentioned. In particular, saturated or unsaturated fatty acid salts of 10 to 20 carbon atoms of these transition metals are preferable, and various transition metal salts such as stearate, linoleate and linolenate or derivatives thereof are preferable in terms of handling and cost. . As a compounding quantity, 0.001-2% of these transition metal compounds are mentioned with respect to the said resin B. FIG. If the amount is less than this amount, the oxygen absorption capacity associated with oxidation decreases. An addition amount larger than this may be used, but since the saturation limit is achieved, the required amount is 2%.

  The next essential component includes a low molecular weight easily oxidizable compound. Typical examples of such compounds include higher unsaturated fatty acids, unsaturated fatty acids such as oleic acid, linoleic acid, linolenic acid and erucic acid, or their polyhydric alcohol derivatives such as glycerol, sorbitol, Examples thereof include, but are not limited to, esterified products such as xylitol. The amount of the low-molecular oxidizable compound added is 0.1 to 20% with respect to the resin B. If it is less than 0.1%, the oxygen absorption capacity is inferior. Although it may be more than 20%, the saturation limit is reached, and the resin composition becomes sticky with bleed-out, which may reduce handling during processing.

  Before explaining the mechanism for causing oxygen absorption of the oxygen-absorbing resin composition of the present invention, the trigger function of a conventional oxygen absorbent will be described as follows. Usually, thermoplastic resins (resin B) having an ethylenically unsaturated bond are very easily oxidized, so various antioxidants (hindered phenols, phosphoruss) are added to impart processing stability and storage stability. , Sulfur and lactone). Resin B in which this antioxidant is not blended can consume oxygen (absorb oxygen) by autooxidation. In order to further promote the auto-oxidation, it is a general technique to blend the above-described oxidation catalyst into the resin B, and this content is the meaning of Patent Document 5. However, the direct blending of an oxidation catalyst with a resin that is easily oxidized is the content that is most worried about the effect of oxidation during processing, and as can be seen from Patent Document 5, ethylene corresponding to resin B is used. In the method of blending an oxidation catalyst with a thermoplastic resin having a system unsaturated bond, a thermoplastic resin and an oxidation catalyst are blended into a solvent, and after completely dissolving and homogenizing, the solvent is removed. The introduction position of the oxidation catalyst is controlled in consideration of the contents and problems, and the process is converted into a thermal process, which corresponds to Patent Document 10, and the thermoplasticity directly corresponds to the oxidation catalyst as the resin B. The result is that it is not necessary to add to the resin. Regarding Patent Document 7, the thermoplastic resin (resin B) having an ethylenically unsaturated bond is considered to be essential to be stabilized by an antioxidant, and then blended with a photosensitizer to start oxygen absorption. The idea that an antioxidant consumes radicals generated by a photosensitizer is included in addition to the idea of generating radicals.

In other words, in order to satisfy the stabilization [above (1)] and the clarification of the trigger mechanism [above (2)], the oxygen-absorbing packaging material is essential for the thermoplastic resin (resin B) having an ethylenically unsaturated bond. How to consume the various antioxidants blended to promote auto-oxidation of resin B can be mentioned. Therefore, as a result of sincerity studies on the method of consuming the antioxidant contained in the resin B, a low molecular weight easily oxidizable compound that can be easily decomposed by heat or UV is blended, and the oxidation catalyst is used for this low molecular weight easily. By blending to promote oxidation of the oxidizing compound and the resin B, the antioxidant in the resin B is easily consumed by heat or UV without blending a conventional photosensitizer, It was found that oxygen absorption can be started by auto-oxidation of resin B.

  In addition, as a result of sincere examination of the blending site (control of morphology) of resin A, resin B, resin C, oxidation catalyst, and low-molecular oxidizable compound, the above-mentioned (1 ) To (5) can be overcome.

  Hereinafter, the structures of the resins A to C are schematically illustrated. FIG. 1 is a schematic conceptual diagram simply showing the structure of a linear polyolefin as an example of the structure of the resin A. FIG. 2 is a schematic conceptual diagram showing a linear block structure of resin B-1 and resin B-2 as an example of the structure of resin B. FIG. 3 is a schematic conceptual diagram showing a structure of a graft polymer or a hydrogenated product of resin B in a unit corresponding to resin A and a unit corresponding to resin B-1 as an example of the structure of resin C. FIG. 4 is a schematic conceptual diagram showing a dispersed state of a resin composition composed of resin A, resin B, and resin C. When the dispersed phase in which the resin B is dispersed in the resin C is defined as the dispersed phase (α), it is preferable to control the morphology as shown in FIG. The dispersed phase (α) is formed from Resin B and Resin C. Resin C has a unit {resin A (C)} corresponding to resin A and a unit {resin B-1 (C)} corresponding to resin B-1, and resin B is resin B-1 and resin B-2. Have That is, since resin B-1 in resin B and resin B-1 (C) in resin C are compatible, as can be seen from FIG. It appears that B-2 is dispersed in a portion corresponding to B-1 of C). That is, it can be seen that the resin B having a glass transition temperature (Tg) ≧ 50 ° C. has a structure in which the resin B-2 serving as the starting point of oxygen absorption is coated. Furthermore, since the dispersed phase (α) has a unit {resin A (C)} corresponding to the resin A of the resin C, it is compatible with the thermoplastic resin (resin A). A unit (resin B-2) composed of a compound having an ethylenically unsaturated bond in the dispersed phase (α) is coated with a unit (resin B-1) composed of a compound having a glass transition temperature (Tg) ≧ 50 ° C. It can be seen that the outer shell is further covered with a unit made of (resin A) in resin C. As an advantage of forming this structure, first, in order to start oxygen absorption in the resin B-2, it is necessary to perform some kind of reaction system via the resin B-1 having a glass transition temperature (Tg) ≧ 50 ° C. There are some cases, and this is effective in imparting heat triggering properties [above (3)] and trapping odor components generated in B-2 [above (4)]. In addition, the oxidation accompanying the radical chain reaction of the resin is affected by the molecular mobility of the thermoplastic resin, and the resin B-1 having a high glass transition temperature restrains the molecular motion of the resin B-2 that is an oxygen absorption unit. It is possible to control reactions (decomposition, etc.) accompanying oxidation more than necessary for oxygen absorption.

Actually, oxygen absorption cannot be started only with FIG. 4, and it is necessary to blend the above-described oxidation catalyst and low-molecular oxidizable compound. Although it does not specifically limit as a site | part which mix | blends the oxidation catalyst and low molecular easily oxidizable compound at this time, In the state which the dispersed phase ((alpha)) which consists of resin B and resin C disperse | distributes to a thermoplastic resin (resin A), The oxidation catalyst (T) and the low molecular oxidizable compound (O) are both on the dispersed phase (α) side, or both are on the resin A side, or the oxidation catalyst is on the resin A side and the low molecular oxidizable compound (O). ) Is blended on the dispersed phase (α) side, the function obtained differs depending on the dispersion position, but it is easy to apply low molecular weight, which gives thermal and UV trigger properties and stability at room temperature. It has been found that it is possible to reduce the odor component derived from the adjustment of the addition amount of the oxidizing compound [(1), (2), (3) above]. In the case of thermal triggering, there are cases in which oxygen absorption is desired to act at a relatively low temperature depending on the required temperature, and there are cases in which it is desired to act in the vicinity of 100 ° C. such as boil and retort. In that case, it is possible to provide a trigger mechanism for starting oxygen absorption at a desired temperature by controlling the blending amount of the low molecular oxidizable compound. More preferably, as a merit of blending the low molecular oxidizable compound (O) into the dispersed phase (α), there is also an effect of making the antioxidant contained in the resin B more easily consumed. It is mentioned that it is possible to suppress the bleed out of the low molecular oxidizable compound. Usually, when a large amount of a low molecular weight easily oxidizable compound (O) is blended with the resin A, stickiness often occurs due to bleed out, but by blending with the dispersed phase (α), the bleed out can be improved. . Probably due to the good compatibility with resin B-1. Further, the temperature triggering property is not generally determined only by the addition amount of the low molecular weight easily oxidizable compound (O), but the glass transition point of the resin B-1 by incorporating the low molecular weight easily oxidizable compound (O). It is estimated that the decrease is effective for temperature-triggered temperature control. However, the antioxidant contained in the resin B gives the oxygen-absorbing function of the resin composition having the oxygen-absorbing ability of the present invention by being consumed by oxidation of the low-molecular oxidizable compound. As a result, the antioxidant contained in the resin B is preferably consumed on the resin A side rather than being consumed in the resin B. Therefore, the resin composition or a laminate or a package using the resin composition is used. It is preferable to determine the blending part of the oxidation catalyst or the low-molecular oxidizable compound according to the function required in the case of the above.

  By forming the above-described structure, low molecular weight easily oxidizable compounds are consumed by active energy rays such as heat or UV (in the presence of an oxidation catalyst), and the antioxidant in the resin B is consumed to suppress the consumption. As a result, the auto-oxidation of the resin B starts and oxygen absorption is expressed. From this content, it is possible to impart heat triggering properties and UV triggering properties without compounding compounds such as photosensitizers that have been problematic in conventional safety.

  Although not an essential component, it is preferable to add a hindered phenol or a phosphorus-based antioxidant to these resin compositions in order to further impart oxygen absorption stability. Moreover, you may mix | blend various additives, such as various additives other than the above, a flame retardant, a slip agent, and an antiblocking agent, as needed.

  As a method for producing these resin compositions having oxygen absorbing ability, various predetermined blending amounts of materials set according to the final product molding method and the required oxygen absorbing ability are used, such as a ribbon mixer, a tumbler mixer, a Henschel mixer, etc. Using dry blending, or blending a predetermined amount using each feeder pre-installed in the kneader, using a single-screw extruder, twin-screw extruder, or other extruder, Banbury or other kneader Depending on the thermoplastic resin used as a base, it can be obtained by kneading at a melting point or higher and 240 ° C. or lower.

  The resin composition having oxygen absorbing ability of the present invention can be formed into a laminate using various molding methods such as extrusion lamination molding, extrusion cast molding, inflation molding, injection molding, and direct blow molding. In addition, it is possible to obtain a laminate by dry lamination, wet lamination, or non-solvent lamination for the film (inflation, etc.) obtained by the molding method described above, and stretch the preform obtained by injection molding. Although it is possible to form a multilayer stretch blow bottle by blow molding, it is not limited to these molding methods.

Although the resin composition having oxygen absorption ability of the present invention has oxygen absorption ability, the thermoplastic resin constituting it is a material having high oxygen permeability. However, there is a problem that oxygen permeation becomes large. Even in the sense of overcoming such a problem, at least one layer of the laminate using the resin composition has an oxygen permeability of 50 cm ³ × 25 μm (thickness) / m ² (area) / 24 h / (1.01325 × It is preferable to provide a barrier layer of 10 ⁵ Pa) (pressure) or less. These materials include polyester resins such as polyethylene terephthalate and polyethylene naphthalate, polyamide 6 and polyamide 6-polyamide 66 copolymers, polyamide resins such as aromatic polyamide, polyacrylonitrile resin, polyvinyl alcohol resin, and ethylene-vinyl alcohol. Thermoplastic resin layer selected from copolymer resin, polyvinylidene chloride resin, metal foil layer such as aluminum foil, PVD deposition method such as aluminum, silica, and alumina, or organosilane such as hexamethylenedisiloxane, acetylene gas, The vapor deposition thermoplastic resin layer obtained by CVD vapor deposition method using another carbon gas source is mentioned. Furthermore, in order to improve the gas barrier property in these vapor deposition layers, especially PVD vapor deposition, a polyvinyl alcohol / silane compound-based overcoat layer may be provided. Moreover, you may provide the various primer layers for improving the adhesiveness of a vapor deposition layer and a thermoplastic resin layer.

  By using these barrier layers, the oxygen gas slightly permeated through these barrier layers is not only completely absorbed by the resin composition layer having oxygen absorbing ability, but also the amount of permeated oxygen gas consumed is reduced. Since there are few, it becomes possible to absorb the oxygen gas of the head space of a package.

  By forming the structure described above, the odor mentioned as a problem associated with oxygen absorption is suppressed as much as possible. However, since it may still generate a slight odor, it is preferable to use a deodorant in that case. As the deodorant, an inorganic compound having a large specific surface area made of silica, alumina, magnesia, titania, zeolite, activated carbon or a mixture thereof is used, or an organic deodorant such as an amine system called a chemical adsorption system is used. Alternatively, it is possible to use a type in which these inorganic and organic materials are combined. The deodorant may be blended in the above-described resin composition having oxygen absorbing ability, or may be blended in a layer forming another laminated structure.

The example of the laminated body in this invention is described below. The symbols constituting the laminate are as shown below. A: polyolefin resin, B: acid anhydride graft-modified polyolefin resin, C: ethylene-vinyl alcohol copolymer, D: alumina-deposited polyester film, E: aluminum foil, F: ethylene- (meth) acrylic acid copolymer, G: Polyvinyl alcohol-based overcoat layer, H: Urethane-based adhesive, I: Polyester film / Structural example-1 : A / B / C / B / oxygen absorbing resin composition Molding method: extrusion molding, injection molding, blow molding Such. Application: Sheets, bottles, cups, trays, etc.
Configuration Example-2 : D / G / H / A / oxygen absorbing resin composition Molding method: extrusion lamination, dry lamination, and the like. Applications: Soft packaging, lid materials, etc.
Configuration Example-3 : I / H / E / F / oxygen absorbing resin composition Molding method: extrusion lamination and the like. Application: Inner cap etc.
Configuration Example-4 : Paper / A / D / G / H / A / oxygen-absorbing resin composition Molding method: extrusion lamination and the like. Application: Composite paper container.

  As described above, the laminates obtained in various configurations can be directly developed into packaging bodies for various uses. These examples are not limited to the contents described above, and can be developed into various packaging forms. Moreover, it becomes possible to form the package body which absorbs oxygen by combining these packaging forms.

  Hereinafter, specific examples of the present invention will be described. The present invention is not limited to these.

[material]
The following materials were used.

Resin A
・ Ethylene-hexene-1 copolymer (MI = 2.2)
Resin B
・ Linear styrene-butadiene-styrene block copolymer (butadiene: 60 wt%)
Resin C
・ Polystyrene grafted polyethylene (polystyrene: 30 wt%)
・ Hydrogenated linear styrene-butadiene-styrene block copolymer (butadiene-60 wt% hydrogenated product)
Transition metal compound stearate Manganese
Low molecular oxidizable compound , oleic acid

[Batch production]
The batch shown below was created.

Batch-1
Resin B / resin C = 35/65 (weight ratio) is dry blended by a twin screw extruder (φ = 30, L / D = 49) at 9 kg / h, 220 ° C., 50 rpm. Compound was performed. Further, at the same time as the compound, liquid addition of a low molecular weight easily oxidizable compound was carried out with the addition amount shown in the following examples to prepare a composition comprising resin B / resin C / low molecular weight easily oxidizable compound.

Batch-2
What was dry blended so that Resin A / Resin B = 85/15 was compounded by a twin screw extruder (φ = 30, L / D = 49) at a discharge rate of 9 kg / h, 220 ° C. and 50 rpm.

Batch-3
A resin blend of manganese stearate and dry blended to a concentration of 1% in terms of metal is discharged by a twin screw extruder (φ = 30, L / D = 49) at 9 kg / h, 180 ° C., 50 rpm. Compound was performed.

Batch-4
Compound obtained by dry blending resin stearate with manganese stearate to a concentration of 1% in terms of metal is discharged with a twin screw extruder (φ = 30, L / D = 49) at 9 kg / h, 180 ° C., 50 rpm. Went.

Batch-5
The resin A was compounded at a discharge rate of 9 kg / h, 180 ° C., and 50 rpm with a twin-screw extruder (φ = 30, L / D = 49) so that the low molecular weight easily oxidizable compound had a concentration of 1%. The low molecular weight easily oxidizable compound was introduced by liquid addition.

  Batches 1 to 5 were all air-cooled pelletized and stored in an aluminum package (replaced with inert gas).

[Film production]
Batches 1 to -5 were dry blended so as to have the compounding ratio shown in the following examples, and then a two-kind three-layer coextruded multilayer film was formed by a three-kind three-layer multilayer film making machine. The layer structure at this time was resin A / oxygen-absorbing resin composition layer / resin A = 15 μm / 30 μm / 15 μm, and the processing temperature at this time was 200 ° C.

[Oxygen absorption capacity evaluation]
The film was cut to a size of 100 × 100 mm and sealed in an aluminum pouch (deaeration seal). Thereafter, 100 ml of air was filled, and the oxygen absorption capacity over time was evaluated. The trigger, as heat triggers, 25 ° C., at 60 ° C., 3 conditions 25 ° C. Storage after boiling treatment 85 ° C.-1H, as a UV triggered using a high-pressure mercury lamp, so that the irradiation energy 350 mJ / cm ² Evaluation was performed on the samples irradiated with the above.

  Examples of [Effect of low molecular weight easily oxidizable compound / oxidation catalyst] are shown below.

<Example 1>
As the resin C, polyethylene grafted with polystyrene was used. In the production of Batch-1, a batch in which no low molecular weight easily oxidizable compound was blended was used. In resin A / resin B / resin C, dry resin A, batch-1, and batch-4 so that the content of resin B is 15 wt% and the transition metal is 3000 ppm in terms of metal relative to resin B. Blending was performed to produce the film. At this time, the oxidation catalyst is present in the dispersed phase (α), and there is no low molecular oxidizable compound. The results are shown in FIGS.

<Example 2>
In the production of Batch-1, the same procedure as in Example 1 was performed except that the amount of the low molecular weight easily oxidizable compound added was 1.5% with respect to the resin B. At this time, the oxidation catalyst is present in the dispersed phase (α), and the low molecular oxidizable compound is present in the dispersed phase (α). The results are shown in FIGS.

<Example 3>
In the production of Batch-1, the same procedure as in Example 1 was performed except that the addition amount of the low molecular weight easily oxidizable compound was 3.0% with respect to the resin B. At this time, the oxidation catalyst is present in the dispersed phase (α), and the low molecular oxidizable compound is present in the dispersed phase (α). The results are shown in FIGS.

<Example 4>
In the production of Batch-1, the same procedure as in Example 1 was performed except that the addition amount of the low molecular weight easily oxidizable compound was 6.0% with respect to the resin B. At this time, the oxidation catalyst is present in the dispersed phase (α), and the low molecular oxidizable compound is present in the dispersed phase (α). The results are shown in FIGS.

<Example 5>
In the production of Batch-1, the same procedure as in Example 1 was performed except that the amount of the low molecular weight easily oxidizable compound added was 9.0% with respect to the resin B. At this time, the oxidation catalyst is present in the dispersed phase (α), and the low molecular oxidizable compound is present in the dispersed phase (α). The results are shown in FIGS.

<Example 6>
In the production of Batch-1, the same procedure as in Example 1 was performed except that the addition amount of the low molecular weight easily oxidizable compound was 15.0% with respect to the resin B. At this time, the oxidation catalyst is present in the dispersed phase (α), and the low molecular oxidizable compound is present in the dispersed phase (α). The results are shown in FIGS.

<Example 7>
In the production of Batch-1, the amount of the low molecular weight easily oxidizable compound added was 15.0% with respect to Resin B, and the same as Example 1 except that Batch-4 was not blended. At this time, there is no oxidation catalyst, and the low molecular oxidizable compound is present in the dispersed phase (α). The results are shown in FIGS.

<Example 8>
In the production of Batch-1, the same as Example 1 except that the low molecular weight easily oxidizable compound was not added and Batch-4 was not further blended. At this time, there is no oxidation catalyst, and no low-molecular oxidizable compound. The results are shown in FIGS.

<Example 9>
In batch-1 production, batch-5 was used as a batch of batch-3 and low-molecular-weight easily oxidizable compound without adding low-molecular-weight easily-oxidizable compound, and adjusted to 1.5% with respect to resin B. Except for the above, this is the same as Example 1. At this time, the oxidation catalyst is present in the resin A, and the low molecular oxidizable compound is also present in the resin A. As for the results of oxygen absorption ability, intermediate results of Examples 3 and 4 were obtained. However, the presence site of the low molecular weight easily oxidizable compound is sometimes referred to as Resin A. Was very sticky and very difficult to handle. However, the obtained multilayer film had no problem. The results showed an intermediate behavior between Example 3 and Example 4.

<Example 10>
Example 1 except that the low molecular weight easily oxidizable compound was not added in the production of Batch-1 and the batch was used as a batch of the low molecular weight easily oxidizable compound and adjusted to 15.0% based on the resin B. Is the same. At this time, the oxidation catalyst is present in the dispersed phase (α), and the low molecular oxidizable compound is present in the resin A. As a result of the oxygen absorption ability, a result close to that of Example 6 was obtained, but the presence site of the low molecular weight easily oxidizable compound was sometimes referred to as Resin A, and Batch-5 was very sticky due to the influence of bleeding during film production. The handling was very difficult, and the resulting multilayer film was not sticky. The results showed behavior similar to Example 6.

<Example 11>
Example 3 is the same as Example 3 except that a hydrogenated linear styrene-butadiene-styrene block copolymer is used as the resin C. The result was the same behavior as in Example 3.

  As shown in FIGS. 5 to 8, when a low molecular weight oxidizable compound or an oxidation catalyst is not blended, oxygen absorption is not exhibited, or auto-oxidation is very slow, whereas in the presence of an oxidation catalyst, a low molecular weight is present. It can be seen that by increasing the blending amount of the easily oxidizable compound, not only the UV trigger property but also the rising of the oxygen absorption ability at a lower temperature is improved. This means that the temperature of the heat trigger can be controlled by the amount of the low molecular weight easily oxidizable compound added. For example, it does not exhibit oxygen absorption in a room temperature range (for example, the aging relationship of the adhesive described later). For example, when it is desired to design oxygen absorption at a temperature of about the boil, the addition amount of the low molecular weight easily oxidizable compound may be about 3 to 6% with respect to the resin B, and oxygen absorption at a lower temperature. When it is desired to express it (such as 25 ° C.), the addition amount of the low molecular weight easily oxidizable compound may be set to 9% or more. In addition, the mixing site of the oxidation catalyst and the low molecular weight easily oxidizable compound can exhibit a very close oxygen absorption behavior regardless of whether it is the dispersed phase (α) or not, but the resin C exists. By this, it becomes possible to mix | blend many more low molecular weight easily oxidizable compounds, and it can respond to the low temperature etc. of a temperature trigger. Moreover, about the addition site | part of an oxidation catalyst and a low molecular weight easily oxidizable compound, even if it mix | blends the amount of low molecular weight easily oxidizable compounds if it mix | blends to the resin A side, compared with the time of mix | blending to the dispersed phase ((alpha)) side. Although it is possible to show an equivalent oxygen absorption behavior with a small amount, stickiness problems also occur, and therefore it is preferable to adjust the blending site according to the intended function.

  Examples of [Effect of Resin C] will be described below.

<Example 12>
Using the film of Example 4, the same evaluation as in Example 1 was performed. Among them, the headspace gas after absorbing oxygen by boil treatment at 85 ° C. for 1 h was used to quantify the generated gas using a Kitagawa gas detector tube. The target gases are aldehydes and acetic acids. The evaluation results are shown in Table 1.

<Example 13>
When the film described in Example 4 was produced, a multilayer film was similarly formed using a resin composition in which 20 wt% of a physical adsorption deodorant was blended with resin A corresponding to the outer layer and the inner layer. The same evaluation was performed. The evaluation results are shown in Table 1.

<Example 14>
Using Batch-2, Batch-3, and Batch-5, the resin composition is such that the compounding ratio of the oxidation catalyst and the low molecular weight easily oxidizable compound is the same as in Example 4 without compounding the resin C. A multilayer film was formed into a film and evaluated in the same manner as in Example 12. The evaluation results are shown in Table 1.

<Example 15>
In the multilayer film of Example 14, a deodorant was used in the same manner as in Example 13. The evaluation results are shown in Table 1.

  From the results in Table 1, it is confirmed that the component of the generated gas accompanying oxygen absorption is reduced depending on the presence or absence of the resin C. Moreover, it is also confirmed that the effect is clarified by adding a deodorant. In the case where the resin C is not blended (Examples 13 and 14), even when the deodorant is blended, a large amount of odor is still generated, and the odor component is further suppressed by controlling the morphology ( It is confirmed that there is an effect of trapping).

  Hereinafter, an example of [Creation of packaging body] will be described.

<Example 16>
The multilayer film of Example 13 was laminated on a base film made of “aluminum foil laminated polyester base (polyester 12 μm, aluminum foil 7 μm)” by a dry laminating method using a polyurethane-based adhesive. The aging temperature at this time cured the adhesive by room temperature aging at 25 ° C. for 5 days in consideration of the temperature trigger property of the multilayer film. The obtained laminate was cut into A4 size, and a three-way seal was performed to prepare a flexible package. At this time, as the contents, 100 ml of distilled water having a dissolved oxygen concentration of 7.8 ppm is filled (head space is adjusted to 0 ml). The amount of dissolved oxygen absorbed when this soft package was stored at 85 ° C. for 1 h was evaluated. The results are shown in Table 2.

<Example 17>
The same as Example 14 except that the substrate film was “alumina-deposited polyester substrate (polyvinyl alcohol / silane coupling agent-based overcoat layer present: 12 μm)”. The results are shown in Table 2.

  Reflecting the results of the above examples, the dissolved oxygen absorption capacity was evaluated using distilled water as the contents, and it was confirmed that the oxygen absorption capacity was also excellent. Moreover, since the film itself has transparency, the merit of this oxygen-absorbing film was also confirmed in terms of contents visibility by using the transparent barrier film shown in Example 16.

It is a schematic conceptual diagram which shows the structure of resin A in this invention. It is a schematic conceptual diagram which shows the structure of resin B in this invention. It is a schematic conceptual diagram which shows the structure of resin C in this invention. It is a schematic conceptual diagram which shows the dispersion state of the resin composition which consists of resin A of this invention, resin B, and resin C. It is a schematic conceptual diagram which shows the dispersion state of the resin composition which mix | blended the oxidation catalyst and low molecular oxidizable compound in this invention. It is a graph which shows the relationship between the storage time of 25 degreeC storage in Examples 1-8, and oxygen absorption amount. It is a graph which shows the relationship between the storage time of 60 degreeC storage in Examples 1-8, and oxygen absorption amount. It is a graph which shows the relationship between the storage time of 25 degreeC storage, and oxygen absorption after 85 degreeC-1h boil processing in Examples 1-8. It is a graph which shows the relationship between the storage time after 350 mJ / cm < ² > ultraviolet irradiation, and oxygen absorption.

Explanation of symbols

A: Thermoplastic resin A
A (C): Resin A unit B in thermoplastic resin (resin C): Thermoplastic resin B
B-1: Resin B-1 in the thermoplastic resin B Unit B-2: Resin B-2 in the thermoplastic resin B Unit C: Thermoplastic resin C
α: Dispersed phase consisting of resin B and resin C (α)
T: oxidation catalyst O: low molecular weight easily oxidizable compound

Claims (21)

Thermoplastic resin (resin A), thermoplastic resin having an ethylenically unsaturated bond (resin B), thermoplastic resin (resin C) having the effect of a compatibilizer for resin A and resin B, oxidation catalyst, low molecular weight A resin composition comprising an oxidizing compound,
The resin A is 50 to 99 wt%, the resin B and the resin C are mixed 1 to 50 wt%, and the oxidation catalyst is 0.001 to 2% with respect to the resin B. A resin composition having an oxygen-absorbing ability, wherein an easily oxidizable compound is blended in an amount of 0.1 to 20% with respect to the resin B. The resin B is a block copolymer of a unit (resin B-1) composed of a compound having a glass transition temperature (Tg) ≧ 50 ° C. and a unit (resin B-2) composed of a compound having an ethylenically unsaturated bond. And
The resin composition having an oxygen absorption capacity according to claim 1, wherein the resin B-1 is 50 to 99 wt% and the resin B-2 is 1 to 50 wt%.   The resin B-1 is selected from one or more of polystyrene, poly (meth) acrylic acid, polyacrylonitrile, or derivatives thereof, and the resin B-2 is selected from one or more of polybutadiene, polyisoprene, or derivatives thereof. The resin composition having oxygen absorbing ability according to claim 2. The resin C is a graft copolymer obtained by grafting a unit composed of the resin B-1 onto the resin A,
The resin composition having an oxygen absorption capacity according to any one of claims 1 to 3, wherein the resin A is 50 to 99 wt% and the resin B-1 is 1 to 50 wt%.   The resin composition having an oxygen absorption capacity according to any one of claims 1 to 3, wherein the resin C is a hydrogenated product of the resin B.   The dispersion state of the resin composition comprising the resin A, the resin B, and the resin C has a structure in which a dispersed phase (α) in which the resin B is dispersed in the resin C is further dispersed in the resin A. The resin composition which has the oxygen absorption ability of any one of 1-5.   The resin B-2 unit of the resin B in the dispersed phase (α) in which the resin B is dispersed in the resin C is in the resin B-1 including the resin B-1 unit of the resin B and the resin B-1 unit of the resin C. 7. The resin composition having oxygen-absorbing ability according to claim 6, wherein the outer shell made of resin B-1 is dispersed and coated with a resin A unit of resin C.   The resin composition having an oxygen absorption capacity according to any one of claims 1 to 7, wherein the oxidation catalyst and the low-molecular oxidizable compound are present at least in the dispersed phase (α). .   The oxidation catalyst is an aromatic carboxylate selected from cobalt, manganese, iron, nickel, copper, cerium, etc., transition metal compound salt such as saturated or unsaturated carboxylate, acetylacetonate, ethylenediamine 9. The resin composition having oxygen absorbing ability according to claim 8, wherein the resin composition is one or more compounds selected from various transition metal complexes such as tetraacetic acid, salen, porphyrin, and phthalocyanine.   9. The resin composition having oxygen absorbing ability according to claim 8, wherein the low-molecular oxidizable compound is a higher unsaturated fatty acid or a derivative thereof.   The thermoplastic resin (resin A) is polyethylene, ethylene-α olefin copolymer, polypropylene, polybutene-1, poly-4-methylpentene-1, ethylene-propylene random copolymer, propylene-ethylene random copolymer, Polyolefin resins such as propylene-ethylene block copolymer, ethylene-propylene-polybutene-1 copolymer, ethylene-cyclic olefin copolymer, ethylene-α, β unsaturated carboxylic acid or esterified product thereof, or ionic cross-linked product thereof An ethylene-vinyl acetate copolymer or an ethylene copolymer represented by a partially saponified product or a completely saponified product thereof, or a graft-modified polyolefin resin, or a mixture of one or more of these, Any one of Claims 1-10 Resin composition having oxygen absorbing capacity according.   The laminated body characterized by including the resin composition layer which has an oxygen absorptivity of any one of Claims 1-11 at least.   The laminate according to claim 12, wherein the resin composition layer has a thickness in the range of 5 to 200 μm. Thermoplastic resin layer, metal foil layer, metal vapor deposition thermoplastic with an oxygen permeability of 50 cm ³ or less under the conditions of 25 μm (thickness) / m ² (area) / 24 h / (1.01325 × 10 ⁵ Pa) (pressure) The laminate according to claim 12 or 13, comprising at least one barrier layer selected from a polymer layer and an inorganic compound-deposited thermoplastic polymer layer.   The thermoplastic resin layer as the barrier layer is a thermoplastic resin layer selected from a polyester resin layer, a polyamide resin layer, a polyacrylonitrile layer, a polyvinyl alcohol layer, an ethylene-vinyl alcohol copolymer layer, and a polyvinylidene chloride layer. The laminate according to claim 14.   The laminate according to claim 14, wherein the metal foil layer is an aluminum foil.   The laminate according to claim 14, wherein the metal of the metal vapor-deposited thermoplastic polymer layer is aluminum.   The laminate according to claim 14, wherein the inorganic compound in the inorganic compound vapor-deposited thermoplastic polymer layer is silica or alumina.   The laminate according to claim 12 or 13, wherein a deodorant is blended in the resin composition layer having oxygen absorbing ability.   A package formed from the laminate according to any one of claims 12 to 19.   21. The package according to claim 20, wherein oxygen absorption is initiated by a temperature of at least 25 ° C. or higher or an active energy ray such as ultraviolet rays.

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