KR20070022159A - Oxygen-absorbing composition and packaging material - Google Patents

Abstract

The oxygen absorbent composition of the present invention contains a gas barrier resin, a salt of an unsaturated carboxylic acid dispersed in the gas barrier resin, and an oxygen absorption accelerator. The cation constituting the salt of the unsaturated carboxylic acid is a cation of at least one element selected from the group consisting of alkali metals, alkaline earth metals and aluminum. The oxygen absorption promoter is at least one selected from the group consisting of transition metal salts, radical generators and photocatalyst particles. The molecular weight of unsaturated carboxylic acid is 3,000 or less.

Oxygen absorbent compositions, gas barrier resins, unsaturated carboxylic acids, oxygen absorption promoters, alkali metals, transition metal salts, radical generators, photocatalyst particles.

Description

Oxygen-absorbing composition and packaging material

The present invention relates to oxygen absorbent compositions and packaging materials.

In order to stably store articles with high deterioration by oxygen such as foods, it is important to store them under an environment with low oxygen. In order to enable such preservation, various oxygen absorbers have been conventionally proposed. For example, an oxygen absorbent encapsulated in a package has been proposed (for example, JP-A-63-198962). Such oxygen absorbers are used in the form of powder, tablets or sheets. However, in the case of storing an article having a large deterioration by oxygen, it is sometimes desirable that the material of the packaging material itself has an oxygen absorbing ability. In order to meet such demands, compositions and the like having oxygen absorbing capacity have been proposed (for example, JP-A-5-115776). The composition of Unexamined-Japanese-Patent No. 5-115776 contains the ethylenically unsaturated hydrocarbon and transition metal catalyst which are the compound to be oxidized (henceforth "the compound to be oxidized"). Carbon-carbon double bonds react with oxygen to absorb oxygen in the presence of transition metal catalysts.

However, in a conventional composition having an oxygen absorbing capacity, sufficient properties may not be obtained in some cases. For example, in the case of a composition in which a oxidized compound is dispersed in a resin, when a packaging material is prepared using this, there is a problem that a component derived from the oxidized compound is eluted from the resin and at the same time a odor is generated.

Disclosure of the Invention

Therefore, an object of the present invention is to provide an oxygen absorbent composition which is difficult to elute the compound to be oxidized from the resin and has high properties such as oxygen absorption ability and a packaging material using the same.

In order to achieve the above object, the oxygen absorbent composition of the present invention contains a gas barrier resin, a salt of an unsaturated carboxylic acid dispersed in a gas barrier resin and an oxygen absorption promoter, and the cation constituting the salt of the unsaturated carboxylic acid is an alkali metal, It is a cation of at least one element selected from the group consisting of alkaline earth metals and aluminum, the oxygen absorption promoter is at least one selected from the group consisting of transition metal salts, radical generators and photocatalyst particles, and the molecular weight of the unsaturated carboxylic acid is 3,000 or less.

In the composition of the present invention, the unsaturated carboxylic acid may be palmitoleic acid, oleic acid, linoleic acid, linolenic acid, arachidonic acid, perinaric acid, dimer acid, docosahexaenoic acid, eicosapentaenoic acid, fish oil fatty acid, linseed oil fatty acid, soybean oil fatty acid, May be one or more selected from the group consisting of paulownia oil fatty acid, sugar oil fatty acid, sesame oil fatty acid, cottonseed oil fatty acid, rapeseed oil fatty acid and tall oil fatty acid.

In the composition of the present invention, the gas barrier resin may include a polyvinyl alcohol-based resin.

Furthermore, the packaging material of this invention WHEREIN: The packaging material containing the part which consists of an oxygen absorbent composition WHEREIN: An oxygen absorbent composition contains a gas barrier resin, the salt of the unsaturated carboxylic acid disperse | distributed to the gas barrier resin, and an oxygen absorption promoter, The cation constituting the salt of the carboxylic acid is a cation of at least one element selected from the group consisting of alkali metals, alkaline earth metals and aluminum, and the oxygen absorption promoter is at least one selected from the group consisting of transition metal salts, radical generators and photocatalytic particles, unsaturated The molecular weight of carboxylic acid is 3,000 or less. Such packaging includes a portion comprised of the oxygen absorbent composition of the present invention as described above.

In the packaging material of the present invention, the portion may be a layer made of an oxygen absorbent composition.

The packaging material of the present invention may include the layer and other layers laminated to the layer.

The oxygen absorbent composition of the present invention uses a specific unsaturated carboxylate as a compound to be compounded. Unsaturated carboxylate salts used in the present invention have low solubility in organic solvents and water and low vapor pressure, which makes it difficult to flow out of the resin and can form a stable packaging material for a long time. Moreover, by using such unsaturated carboxylate, it becomes possible to form the oxygen absorption layer with little coloring.

The packaging material of the present invention can be used as a packaging material such as an article having a large influence of deterioration due to oxygen, for example, food, medicine, medical substrates, machine parts, clothing, etc., and is particularly preferable as a packaging material used under conditions of high temperature and high humidity. Do.

BRIEF DESCRIPTION OF THE DRAWINGS It is a graph which shows an example of the characteristic of the oxygen absorbent composition of this invention using linoleate.

2 is a graph showing another example of the properties of the oxygen absorbent composition of the present invention using linoleate.

3 is a graph showing another example of the properties of the oxygen absorbent composition of the present invention using linoleate.

4 is a graph showing another example of the properties of the oxygen absorbent composition of the present invention using linoleate.

It is a graph which shows an example of the characteristic of the oxygen absorbent composition of this invention using eicosapentaenoate.

6 is a graph showing another example of the properties of the oxygen absorbent composition of the present invention using eicosapentaenoate.

7 is a graph showing another example of the characteristics of the oxygen absorbent composition of the present invention using eicosapentaenoate.

8 is a graph showing another example of the properties of the oxygen absorbent composition of the present invention using eicosapentaenoate.

It is a graph which shows another example of the characteristic of the oxygen absorbent composition of this invention using sodium docosahexanoate.

10 is a graph showing an example of the properties of the oxygen absorbent composition of the present invention using eleostearate and the oxygen absorbent composition of the comparative example using eleostearic acid.

FIG. 11 is a graph showing another example of the properties of the oxygen absorbent composition of the present invention using eleostearate and the oxygen absorbent composition of the comparative example using eleostearic acid.

12 is a graph showing another example of the properties of the oxygen absorbent composition of the present invention using eleostearate and the oxygen absorbent composition of the comparative example using eleostearic acid.

13 is a graph showing another example of the properties of the oxygen absorbent composition of the present invention using eleostearate and the oxygen absorbent composition of the comparative example using eleostearic acid.

Best Mode for Carrying Out the Invention

EMBODIMENT OF THE INVENTION Hereinafter, embodiment of this invention is described. In addition, although the specific compound may be illustrated as a substance which expresses a specific function in the following description, this invention is not limited to this. In addition, unless otherwise indicated, the material illustrated can be used individually and can also be used in combination.

(Embodiment 1)

In Embodiment 1, the oxygen absorbent composition of the present invention will be described. The oxygen absorbent composition of Embodiment 1 contains a gas barrier resin, a salt of unsaturated carboxylic acid dispersed in the gas barrier resin (hereinafter may be referred to as carboxylate (A)), and an oxygen absorption accelerator. The cation constituting the carboxylate (A) is a cation of at least one element selected from the group consisting of alkali metals, alkaline earth metals and aluminum. In addition, the oxygen absorption promoter is at least one selected from the group consisting of transition metal salts, radical generators and photocatalyst particles. And the molecular weight of unsaturated carboxylic acid is 3,000 or less.

Hereinafter, carboxylate (A) is demonstrated. Examples of the alkali metal constituting the carboxylate (A) include sodium and potassium. As alkaline earth metal which comprises a carboxylate (A), magnesium, calcium, barium, strontium is mentioned, for example. The carboxylic acid salt (A) using alkaline earth metal has low water solubility compared with the carboxylic acid salt (A) using alkali metal, and therefore the elution of carboxylate (A) to water can be suppressed. Among these, calcium is preferable in view of being harmless for safety and hygiene.

The carboxylate (A) using aluminum has a lower solubility in water and a lower vapor pressure than the carboxylate (A) using calcium, further suppressing the elution of the carboxylate (A) to water and outflow from the resin. can do. Further, by using a neutral metal such as aluminum, decarboxylation decomposition of the carboxylate (A) can be suppressed and a stable packaging material can be formed over a long period of time.

In the present invention, the carboxylic acid constituting the carboxylate (A) preferably has a small molecular weight. The molecular weight of the carboxylic acid which comprises a carboxylate (A) is 3,000 or less, Preferably it is 500 or less, for example, 100-400. The carboxylate (A) derived from the carboxylic acid whose molecular weight is 3,000 or less can be easily disperse | distributed to resin. In addition, the chemical formula of the carboxylate (A) formed by the divalent cation is about twice the molecular weight of the carboxylic acid, and the chemical formula of the carboxylate (A) formed by the trivalent cation is three times the molecular weight of the carboxylic acid. It is about.

Carboxylate (A) contains a carbon-carbon double bond. The carboxylic acid salt (A) may be a salt of a monocarboxylic acid, and may be a salt of a polycarboxylic acid such as dicarboxylic acid. The carboxylate (A) may be a linear or chain acyclic compound, or may be a cyclic compound having an unsaturated alicyclic structure. When the unsaturated carboxylic acid which has a side chain is used, a side chain part may decompose according to oxygen absorption, and a low molecular substance (odor substance) may generate | occur | produce. In order to suppress the generation of low molecular weight substances due to oxygen absorption, it is preferable to use a straight chain unsaturated carboxylate or an unsaturated carboxylate having an alicyclic structure. Examples of the unsaturated carboxylic acid constituting the carboxylate (A) include palmilean acid, oleic acid, linoleic acid, linolenic acid, arachidonic acid, perinarinic acid, dimer acid, docosahexaenoic acid, eicosapentaenoic acid, and fish oil. And at least one selected from the group consisting of fatty acids, linseed oil fatty acids, soybean oil fatty acids, paulownia oil fatty acids (mainly eleostearic acid), sugar oil fatty acids, sesame oil fatty acids, cottonseed oil fatty acids, rapeseed oil fatty acids and tall oil fatty acids. Among them, a composition having high oxygen absorption capacity is obtained by using linolenic acid, docosahexaenoic acid, and eicosapentaenoic acid having a large number of double bonds in the molecule.

The ratio of the number Nd of carbon-carbon double bonds to the total carbon number Nc in the carboxylate (A), the value of Nd / Nc, is usually in the range of 0.005 to 0.5, for example, in the range of 0.05 to 0.3. By setting the range of Nd / Nc to 0.15 or more, a composition having high oxygen absorption capacity is obtained.

Examples of the carboxylate (A) include alkali salts of sodium palmitate, sodium oleate, sodium linoleate, sodium linoleate, sodium arachidonic acid, sodium perlinate, sodium dimer, sodium docosahexaenoate and sodium eicosapentaenoate. Sodium fish oil, sodium linseed oil, sodium soybean oil, sodium oleostearate, potassium palmitate, potassium oleate, potassium linoleate, potassium linoleate, potassium arachidonic acid, potassium perinaline, potassium dimerate, docosahexa Potassium enoate, potassium eicosapentaenoate, fish oil fatty acid potassium, linseed oil fatty acid potassium, soybean oil fatty acid potassium, potassium eleostearate, etc. are mentioned.

Moreover, as carboxylate (A) containing alkaline-earth metal, calcium palmitate, calcium oleate, calcium linoleate, calcium linoleate, calcium arachidonic acid, calcium furininarate, calcium dimer, calcium docosahexaenoate, eicosapenta Calcium nitrate, fish oil fatty acid calcium, linseed oil fatty acid calcium, soybean oil fatty acid calcium, calcium eleostearate, magnesium palmitate, magnesium oleate, magnesium linoleate, magnesium linoleate, magnesium arachidonic acid, magnesium perlininate, magnesium dimer Docosahexaenoic acid magnesium, eicosapentaenoic acid magnesium, fish oil fatty acid magnesium, linseed oil fatty acid magnesium, soybean oil fatty acid magnesium, magnesium eleostearate, barium oleate, barium oleate, barium linoleate, barium linoleate, barium arachidonic acid , Barium perinarate, barium dimer, barium docosahexaenoate, barium eicosapentaenoate, Oil fatty acids may include barium, barium linseed oil fatty acids, soybean oil fatty acid barium, eleostearic acid and barium.

Moreover, as carboxylate (A) containing aluminum, aluminum palmitate, aluminum oleate, aluminum linoleate, aluminum linoleate, aluminum arachidonic acid, aluminum perinaline, aluminum dimer acid, docosahexaenoate, for example , Eicosapentaenoate, fish oil fatty acid aluminum, linseed oil fatty acid aluminum, soybean oil fatty acid aluminum, aluminum eleostearate and the like.

Among them, calcium linoleate, calcium docosahexaenoate, calcium eicosapentaenoate, which are excellent in oxygen absorption ability, can inhibit the elution of carboxylate (A) to water, and are harmless for safety and hygiene. Fish oil fatty acid calcium is preferred. Further, considering that the decarboxylation of the carboxylate (A) can be suppressed and that a stable packaging material can be formed over a long period of time, aluminum linoleate, aluminum docosahexaenoate, aluminum eicosapentaenoate, and fish oil fatty acid aluminum This is more preferable.

It is preferable that carboxylate (A) is disperse | distributed favorably in a composition. In the various molded articles which consist of the composition of such a state, oxygen absorption and gas barrier property are easy to maintain, and it is preferable at the point which can provide the function which a gas barrier resin has. Moreover, transparency is also favorable. At this time, the average particle diameter of the dispersed carboxylate (A) particles is preferably 10 μm or less. When the average particle diameter exceeds 10 µm, the interface area between the carboxylate (A) and a resin other than the carboxylate (A) decreases, and the oxygen gas barrier property may decrease, and the oxygen absorption performance may decrease. . From the viewpoint of oxygen absorption, gas barrier properties and transparency of molded articles such as multilayer containers using the composition, the average particle diameter of the dispersed carboxylate (A) particles is more preferably 5 µm or less, further preferably 2 µm or less. Do. Here, an average particle diameter means that the cross section of the composition was image | photographed by the magnification of 3000 times with the scanning electron microscope, and the average particle diameter of all the particle | grains which exist in a visual field is mean.

An oxygen absorption promoter is a substance for promoting oxidation of carboxylate (A) containing a carbon-carbon double bond. Oxygen in the atmosphere is consumed by the oxidation of the carboxylate (A). Particularly high oxygen absorption capacity is obtained by using a transition metal salt as an oxygen absorption promoter.

As a transition metal which comprises a transition metal salt, iron, nickel, copper, manganese, cobalt, rhodium, titanium, chromium, vanadium, and ruthenium are mentioned, for example. Among these, iron, nickel, copper, manganese and cobalt are preferable. As an anion which comprises a transition metal salt, the anion derived from an organic acid or a chloride is mentioned, for example. Examples of the organic acid include acetic acid, stearic acid, dimethyldithiocarbamic acid, palmitic acid, 2-ethylhexanoic acid, neodecanoic acid, linoleic acid, tolic acid, oleic acid, resinous acid, capric acid and naphthenic acid. have. Since a transition metal salt is added for the purpose of using as an oxygen absorption promoter, the organic acid which comprises this may contain a carbon-carbon double bond, and may not contain a carbon-carbon double bond. Representative transition metal salts include, for example, cobalt 2-ethylhexanoate, cobalt neodecanoate, cobalt naphthenate and cobalt stearate. In addition, an ionomer can be used as a transition metal salt.

As a radical generator, N-hydroxy succinimide, N-hydroxy maleic acid imide, N, N'- dihydroxy cyclohexane tetracarboxylic acid imide, N-hydroxy phthalic acid imide, N-, for example Hydroxy tetrachlorophthalic acid imide, N-hydroxy tetrabromophthalic acid imide, N-hydroxyhexahydrophthalic acid imide, 3-sulfonyl-N-hydroxyphthalic acid imide, 3-methoxycarbonyl-N -Hydroxyphthalic acid imide, 3-methyl-N-hydroxyphthalic acid imide, 3-hydroxy-N-hydroxyphthalic acid imide, 4-nitro-N-hydroxyphthalic acid imide, 4-chloro-N- Hydroxyphthalic acid imide, 4-methoxy-N-hydroxyphthalic acid imide, 4-dimethylamino-N-hydroxyphthalic acid imide, 4-carboxy-N-hydroxyhexahydrophthalic acid imide, 4-methyl- N-hydroxyhexahydrophthalic acid imide, N-hydroxyHET acid imide, N-hydroxy high Acid can be cited Mead, N- hydroxy trimellitic acid imide, N, N- di-hydroxyalkyl pyromellitic sandiyi imide and the like. Among these, N-hydroxy succinimide, N-hydroxy maleic acid imide, N-hydroxy hexahydro phthalic acid imide, N, N'- dihydroxy cyclohexane tetracarboxylic acid imide, and N-hydroxy phthalic acid Mid, N-hydroxy tetrabromophthalic acid imide, and N-hydroxy tetrachloro phthalic acid imide are especially preferable.

Photocatalyst particle | grains are particle | grains which function as a catalyst of the oxidation reaction of carboxylate (A) by irradiation of light. Examples of the photocatalyst particles include particles of titanium dioxide, tungsten oxide, zinc oxide, cerium oxide, strontium titanate and potassium niobate. These are usually used in the form of powders. Among these, titanium dioxide is preferable because it has high photocatalyst function, is recognized as a food additive, safe and inexpensive. It is preferable that titanium dioxide is an anatase type, and it is preferable that 30 weight% or more (more preferably 50 weight% or more) of a titanium dioxide powder is anatase type titanium dioxide. High photocatalytic action is obtained by using anatase type titanium dioxide.

The gas barrier resin is selected according to the use of the composition. Examples of the gas barrier resin include synthetic resins such as polyvinyl alcohol resins, polyamide resins, and polyacrylonitrile resins. Any one of these may be used alone, or one or more thereof may be mixed and used. Since these resins have high oxygen barrier properties, the use of these resins yields compositions suitable for packaging materials for articles in which degradation by oxygen is a problem. Among these resins, polyvinyl alcohol-based resins are preferred because the dispersibility of the carboxylate (A) is good. Oxygen permeability of gas barrier resin is less than 500ml · 20㎛ / (m ² · day · atm) (20 ℃, 65% RH) It means that the volume of oxygen permeating a film having an area of 1 m ² , 20 μm in one day in the state of pressure difference is 500 ml or less.), For example, 20 ml · 20 μm / (m ² · day atm) or less.

Moreover, the oxygen absorbent composition of this invention can contain resin of that excepting the above. As such resin, for example, polyolefins such as polyethylene, polypropylene, poly4-methyl-1-pentene, poly1-butene and the like can be used. Moreover, ethylene propylene copolymer, polyvinylidene chloride, polyvinyl chloride, polystyrene, polycarbonate, polyacrylate can be used. In addition, polyesters such as polyethylene terephthalate, polybutylene terephthalate and polyethylene naphthalate can be used. It is also possible to use copolymers of ethylene or propylene with other monomers. As another monomer, For example, alpha-olefins, such as 1-butene, isobutene, 4-methyl-1- pentene, 1-hexene, 1-octene; Unsaturated carboxylic acids such as itaconic acid, methacrylic acid, acrylic acid, maleic anhydride, salts thereof, partial or complete esters thereof, nitriles thereof, amides thereof, anhydrides thereof; Carboxylic acid vinyl esters such as vinyl formate, vinyl acetate, vinyl propionate, vinyl butyrate, vinyl octanoate, vinyl dodecanoate, vinyl stearate and vinyl arachidonate; Vinylsilane-based compounds such as vinyltrimethoxysilane; Unsaturated sulfonic acids or salts thereof; Alkyl thiols; Vinylpyrrolidones can be mentioned.

The polyvinyl alcohol resin is obtained by saponifying a homopolymer of vinyl ester or a copolymer of vinyl ester with another monomer (particularly, copolymer of vinyl ester and ethylene) using an alkali catalyst or the like. As vinyl ester, although vinyl acetate is mentioned, other fatty acid vinyl ester (vinyl propionate, vinyl pivalate, etc.) can be used, for example.

Preferably the degree of saponification of the vinyl ester component of polyvinyl alcohol-type resin is 90 mol% or more, for example, 95 mol% or more. By making saponification degree 90 mol% or more, the fall of gas barrier property can be suppressed under high humidity. Moreover, two or more types of polyvinyl alcohol-type resins in which saponification degree differs can be used. Saponification degree of polyvinyl alcohol-type resin can be calculated | required by the nuclear magnetic resonance (NMR) method.

The appropriate melt flow rate (based on Japanese Industrial Standards (JIS) K7210 at 210 ° C and 2160 g load) of the polyvinyl alcohol resin is 0.1 to 100 g / 10 minutes, more preferably 0.5 to 50 g / 10 minutes, more suitably. Is 1 to 30 g / 10 minutes. When the melt flow rate deviates from the range of 0.1 g to 100 g / 10 minutes, the workability at the time of melt molding often worsens.

When using polyvinyl alcohol-type resins, such as an ethylene-vinyl alcohol copolymer (EVOH), it is preferable to use an aluminum salt for carboxylate (A). By using such carboxylate (A), coloring of the composition of this invention can be reduced.

Among the polyvinyl alcohol-based resins, the ethylene-vinyl alcohol copolymer (EVOH) is capable of melt molding and has good gas barrier properties under high humidity. The proportion of ethylene units occupying the entire structural unit of EVOH is, for example, in the range of 5 to 60 mol% (preferably 10 to 55 mol%). By reducing the ratio of ethylene units to 5 mol% or more, it is possible to suppress the deterioration of gas barrier properties under high humidity. Moreover, high gas barrier property is obtained by making the ratio of an ethylene unit into 60 mol% or less. The ratio of an ethylene unit can be calculated | required by the nuclear magnetic resonance (NMR) method. Moreover, the mixture of two or more types of EVOH in which the ratio of ethylene units differs can be used.

In addition, as long as the effects of the present invention are obtained, EVOH may contain a small amount of other monomers as a copolymerization component. As an example of such a monomer, For example, alpha-olefins, such as propylene, 1-butene, isobutene, 4-methyl-1- pentene, 1-hexene, 1-octene; Unsaturated carboxylic acids and derivatives thereof such as itaconic acid, methacrylic acid, acrylic acid and maleic anhydride; Vinylsilane-based compounds such as vinyltrimethoxysilane, vinyltriethoxysilane, vinyltri (β-methoxy-ethoxy) silane, and γ-methacryloxypropyltrimethoxysilane; Unsaturated sulfonic acids or salts thereof; Alkyl thiols; Vinylpyrrolidones can be mentioned. When EVOH contains 0.0002-0.2 mol% of a vinylsilane compound as a copolymerization component, it becomes easy to manufacture a homogeneous molding when shaping | molding by co-extrusion molding or construction extrusion molding. As a vinylsilane type compound, vinyl trimethoxysilane and vinyl triethoxysilane are used suitably.

In addition, a boron compound can be added to EVOH. This facilitates the production of a homogeneous molded article when forming by coextrusion molding or construction extrusion molding. As a boron compound, boric acid (for example, orthoboric acid), a boric acid ester, a boric acid salt, and boron hydride are mentioned, for example. In addition, alkali metal salts (eg, sodium acetate, potassium acetate, sodium phosphate) may be added to EVOH. Thereby, interlayer adhesiveness and compatibility may be improved in some cases. In addition, a phosphoric acid compound (e.g., sodium dihydrogen phosphate, potassium dihydrogen phosphate, disodium hydrogen phosphate, dipotassium hydrogen phosphate) may be added to EVOH. Thereby, the thermal stability of EVOH can be improved in some cases. EVOH to which additives, such as a boron compound, an alkali metal salt, and a phosphorus compound, were added can be manufactured by a well-known method.

The kind of the polyamide-based resin is not particularly limited, and for example, polycaproamide (nylon-6), polyundecanamide (nylon-11), polylauryllactam (nylon-12), polyhexamethyleneadipa Aliphatic polyamide homopolymers such as mead (nylon-6,6) and polyhexamethylene sebacamide (nylon-6,10); Caprolactam / laurolactam copolymer (nylon-6 / 12), caprolactam / aminoundecanoic acid copolymer (nylon-6 / 11), caprolactam / ω-aminononanoic acid copolymer (nylon-6 / 9), Caprolactam / hexamethyleneadipamide copolymer (nylon-6 / 6,6), caprolactam / hexamethyleneadipamide / hexamethylene sebacamide copolymer (nylon-6 / 6,6 / 6,10) Aliphatic polyamide copolymers; Aromatic polyamide, such as polymethaxylylene adipamide (MX-nylon) and hexamethylene terephthalamide / hexamethylene isophthalamide copolymer (nylon-6T / 6I), is mentioned. These polyamide resins may be used independently, respectively and may mix and use two or more types. Among these, polycaproamide (nylon-6) and polyhexamethyleneadipamide (nylon-6,6) are preferable.

As polyacrylonitrile-type resin, the homopolymer of acrylonitrile and the copolymer of monomers, such as an acrylate ester, and an acrylonitrile are mentioned.

The composition of Embodiment 1 is an antioxidant, plasticizer, heat stabilizer (melt stabilizer), photoinitiator, deodorant, ultraviolet absorber, antistatic agent, lubricant, colorant, filler, filler, pigment, dye, as long as the effect of the present invention is obtained. It may contain one or more additives such as processing aids, flame retardants, antifogging agents and desiccants.

There is no restriction | limiting in particular in the quantity of the carboxylate (A) and oxygen absorption promoter contained in the composition of Embodiment 1, It adjusts according to the kind and objective of each component. In one example of the composition where the carboxylate (A) is an unsaturated monocarboxylic acid salt and the oxygen absorption promoter is a transition metal salt, for example, the amount of the carboxylate (A) is 1 part by weight to 30 parts by weight based on 100 parts by weight of the gas barrier resin. The amount is in the range of 5 parts by weight to 10 parts by weight (for example, 5 parts by weight to 10 parts by weight), and the amount of the oxygen absorption promoter is 10 ^-4 parts by weight to 100 parts by weight (for example, 10 ^-2 parts by weight to 100 parts by weight of the carboxylate (A)). 0.1 part by weight). Moreover, even if carboxylate (A) is carboxylate other than unsaturated monocarboxylic acid salt, it can be set as the same ratio.

In addition, when using a photocatalyst as an oxygen absorption promoter, you may make the quantity of a photocatalyst into the range of 0.1 weight part-100 weight part (for example, the range of 0.5 weight part-10 weight part) with respect to 100 weight part of carboxylate (A).

In the case of using a radical generator as the oxygen absorption promoter, the amount of the radical generator is in the range of 0.1 parts by weight to 100 parts by weight based on 100 parts by weight of the carboxylate (A) (for example, 0.5 parts by weight to 10 parts by weight). Range).

The composition of this invention can be formed by mixing components, such as a gas barrier resin, a carboxylate (A), an oxygen absorption promoter, and an additive. There is no restriction | limiting in particular in the method of mixing each component, and the order of mixing, All the components can also be mixed simultaneously, and each component can be mixed in arbitrary order. For example, the carboxylate (A) and the oxygen absorption promoter may be mixed in advance and then mixed with other components. Moreover, after mixing a carboxylate (A) and an additive, it can mix with an oxygen absorption promoter and resin. Moreover, after mixing an oxygen absorption promoter and resin, it can mix with a carboxylate (A) and an additive. Moreover, after mixing a carboxylate (A), resin, and an additive, it can mix with an oxygen absorption promoter. Moreover, after mixing an oxygen absorption promoter and an additive, it can mix with a carboxylate (A) and resin. Moreover, the mixture obtained by mixing carboxylate (A), resin, and an additive, and the mixture obtained by mixing an oxygen absorption promoter and resin can be mixed.

As a specific method of mixing, for example, a method of dissolving each component in a solvent to prepare a plurality of solutions, mixing these solutions, evaporating the solvent, or adding another component to the melted resin and kneading them Can be mentioned.

Kneading | mixing can be performed using a ribbon compounder, a high speed mixer, a kneader, a mixing roll, an extruder, or an intensive mixer, for example.

The compositions of the present invention can be molded into various forms, such as films, sheets, containers, and the like. These moldings can be used as a packaging material or an oxygen scavenger. It can also be used as part of a packaging container. The composition of this invention can be used as a material which comprises some layer of a laminated body. Moreover, the composition of this invention can be shape | molded once as pellets, and each component of a composition can be dry-blended and shape | molded directly.

(Embodiment 2)

In Embodiment 2, the packaging material of this invention is demonstrated. The packaging material of this invention contains the part which consists of the oxygen absorbent composition demonstrated in Embodiment 1. This part may have any shape and may be, for example, a layered shape, a bottle shape or a cap shape. Such a packaging material can be formed by processing the composition of Embodiment 1 into various shapes.

The composition of Embodiment 1 can be molded into the shape of a film, sheet, pipe or the like by, for example, a melt extrusion molding method. Moreover, it can shape | mold in container shape by the injection molding method. It can also be molded into a hollow container such as a bottle by the blow molding method. As blow molding, extrusion blow molding or injection blow molding can be applied, for example.

The packaging material of Embodiment 2 may consist only of the layer (henceforth referred to as layer (A)) which consists of the composition of Embodiment 1, and the other layer (henceforth layer B) which consists of different materials may be It may be a laminate. By setting it as a laminated body, characteristics, such as mechanical characteristics, a water vapor barrier, and an oxygen barrier, can be improved more. The material and number of layers (B) are selected according to the properties required for the packaging material.

The structure of the laminate is not particularly limited. An adhesive resin layer (hereinafter sometimes referred to as layer (C)) for adhering both can be disposed between the layer (A) and the layer (B). The structure of a laminated body is a layer (A) / layer (B), a layer (B) / layer (A) / layer (B), a layer (A) / layer (C) / layer (B), Layer (B) / layer (C) / layer (A) / layer (C) / layer (B), layer (B) / layer (A) / layer (B) / layer (A) / layer (B) and Layer (B) / layer (C) / layer (A) / layer (C) / layer (B) / layer (C) / layer (A) / layer (C) / layer (B). If the laminate comprises a plurality of layers (B), they may be the same or different. The thickness of each layer of a laminated body is not specifically limited. When the ratio of the thickness of the layer (A) to the thickness of the whole laminate is in the range of 2 to 20%, it may be advantageous in terms of moldability and cost.

The layer (B) can be formed of, for example, a thermoplastic resin, a metal, paper, or the like. As a metal used for layer (B), steel, aluminum, etc. are mentioned, for example. Examples of the paper that can be used for the layer (B) include white paper, manila balls, milk cartoon paper, cup paper, ivory paper and the like. Although the thermoplastic resin used for layer (B) is not specifically limited, For example, resin illustrated about the layer (A) can be used. For example, polyolefins, such as polyethylene, a polypropylene, poly4-methyl-1- pentene, poly 1-butene, can be used. In addition, an ethylene-propylene copolymer, polyvinylidene chloride, polyvinyl chloride, polystyrene, polyacrylonitrile, polycarbonate, polyacrylate, ethylene-vinyl alcohol copolymer can be used. In addition, polyesters such as polyethylene terephthalate, polybutylene terephthalate and polyethylene naphthalate can be used. In addition, polyamides such as polycaproamide, polyhexamethyleneadipamide, and polymethaxylyleneadipamide can be used. It is also possible to use copolymers of ethylene or propylene with other monomers. As another monomer, For example, alpha-olefins, such as 1-butene, isobutene, 4-methyl-1- pentene, 1-hexene, 1-octene; Unsaturated carboxylic acids such as itaconic acid, methacrylic acid, acrylic acid, maleic anhydride, salts thereof, partial or complete esters thereof, nitriles thereof, amides thereof, anhydrides thereof; Carboxylic acid vinyl esters such as vinyl formate, vinyl acetate, vinyl propionate, vinyl butyrate, vinyl octanoate, vinyl dodecanoate, vinyl stearate and vinyl arachidonate; Vinylsilane-based compounds such as vinyltrimethoxysilane; Unsaturated sulfonic acids or salts thereof; Alkyl thiols; Vinylpyrrolidones can be mentioned.

Layers (A) and (B) may be unstretched and may be stretched or rolled uniaxially or biaxially.

The adhesive resin used for layer (C) is not specifically limited as long as it can adhere | attach each layer. For example, one- or two-component curable adhesives of polyurethane or polyester or copolymers or graft-modified unsaturated carboxylic acids or anhydrides thereof (such as maleic anhydride) to olefin polymers (carboxylic acid-modified polyolefin resins) Can be used. When layer (A) and layer (B) contain a polyolefin resin, high adhesiveness can be implement | achieved by using a carboxylic acid modified polyolefin resin. Examples of the carboxylic acid-modified polyolefin resins include resins obtained by carboxylic acid-modifying polymers such as polyethylene, polypropylene, copolymerized polypropylene, ethylene-vinyl acetate copolymers, and ethylene- (meth) acrylic acid ester copolymers. .

A deodorant can be mix | blended with one or more layers of the layer which comprises a laminated body. As a deodorant, the deodorant illustrated in Embodiment 1 can be used, for example.

The manufacturing method of the laminated body of Embodiment 2 is not specifically limited, For example, it can form by a well-known method. For example, methods, such as an extrusion lamination method, a dry lamination method, a solvent casting method, a construction extrusion molding method, and a coextrusion molding method, are applicable. As the coextrusion molding method, for example, a coextrusion laminate method, a coextrusion sheet molding method, a coextrusion inflation molding method, or a coextrusion blow molding method can be applied.

In the case where the packaging material of the present invention is a container having a multi-layer structure, it is possible to quickly absorb oxygen in the container by disposing a layer made of the composition of Embodiment 1 in a layer close to the inner surface of the container, for example, the innermost layer.

This invention is used suitably for the multilayer container which the thickness of a whole layer is 300 micrometers or less, or a multilayer container manufactured by the extrusion blow molding method also in a multilayer container.

The multilayer container having a total thickness of 300 μm or less is a container made of a relatively thin multilayer structure such as a multilayer film, and is usually used in the form of a pouch or the like. Flexible, easy to manufacture, excellent gas barrier properties, and has a continuous oxygen absorption function, it is very useful for packaging products that are highly sensitive to oxygen and susceptible to degradation. High flexibility is obtained by setting the total layer thickness to 300 µm or less. Higher flexibility is obtained by setting the thickness of the entire layer to 250 µm or less, particularly 200 µm or less. In consideration of mechanical strength, the total layer thickness is preferably 10 μm or more, more preferably 20 μm or more.

In order to seal such a multilayer container, at least one surface layer of the multilayer film is preferably a layer made of a resin that can be heat sealed. As such resin, polyolefin, such as polyethylene and a polypropylene, is mentioned, for example. A multilayer container is obtained by filling a bag into a multilayer film processed into a bag and heat-sealing the contents.

On the other hand, the multilayer container manufactured by the extrusion blow molding method is usually used in the form of a bottle or the like. It is very useful for the packaging of products that are highly sensitive to oxygen and susceptible to deterioration because of high productivity and excellent gas barrier properties and continuous oxygen absorption.

The thickness of the trunk portion of the bottle-shaped container is generally in the range of 100 to 2000 µm, and is selected according to the use. In this case, the thickness of the layer which consists of the composition of Embodiment 1 can be made into the range of 2-200 micrometers, for example.

The packaging material of the invention may be a packing (gasket) for a container, in particular a gasket for a container cap. In this case, a gasket is formed by the composition of Embodiment 1.

Hereinafter, the present invention will be described in more detail using examples. First, unsaturated carboxylate is manufactured by the following method.

(Calcium linoleate)

24.00 g of linolenic acid, 3.19 g of calcium hydroxide and 100 ml of toluene were mixed, and after azeotropic dehydration for 4 hours, toluene was distilled off. The product obtained is allowed to cool and then dried under reduced pressure to obtain calcium linoleate.

(Sodium linoleate)

24.00 g of linolenic acid, 3.45 g of sodium hydroxide, and 100 ml of toluene are mixed, and after azeotropic dehydration for 4 hours, toluene is distilled off. The obtained product was allowed to cool and then dried under reduced pressure to obtain sodium linoleate.

(Aluminum Linoleate)

24.00 g of linolenic acid, 3.45 g of sodium hydroxide, and 100 ml of toluene are mixed, and after azeotropic dehydration for 4 hours, toluene is distilled off. The obtained product was allowed to cool and then dried under reduced pressure to obtain sodium linoleate. An aqueous solution in which 2.44 g of aluminum sulfate (14-18 hydrates) was dissolved in 20 ml of water was added to an aqueous solution in which 12.86 g of dried sodium linoleate was dissolved in 230 ml of water over 30 minutes. The precipitated product is taken out and dried in vacuo at 60 ° C. to yield 12.00 g of aluminum linoleate (pale yellow).

(Calcium Eicosapentaenoate)

28.3 g of eicosapentaenoic acid ethyl ester (manufactured by Kyowa Technos Co., Ltd.), 3.19 g of calcium hydroxide, and 100 ml of toluene are mixed and azeotropically for 3 hours, and then toluene is distilled off. The obtained product was allowed to cool and then dried under reduced pressure to obtain calcium eicosapentaenoate (EPA-Ca).

Sodium Eicosapentaenoate

After dissolving 1.26 g (31.5 mmol) of sodium hydroxide in 45.0 g of ethanol, 10.00 g (30.3 mmol) of eicosapentaenoic acid ethyl ester (manufactured by Kyowa Technos Co., Ltd.) was added and refluxed for 4 hours. The reaction solution is concentrated by an evaporator and dried under reduced pressure to obtain sodium eicosapentaenoate (EPA-Na).

(Barium Eicosapentaenoate)

After dissolving 1.26 g (31.5 mmol) of sodium hydroxide in 45.0 g of ethanol, 10.00 g (30.3 mmol) of eicosapentaenoic acid ethyl ester (manufactured by Kyowa Technos Co., Ltd.) was added and refluxed for 4 hours. The reaction solution is concentrated with an evaporator and dried under reduced pressure to obtain sodium eicosapentaenoate. An aqueous solution of 3.2 g of barium chloride dissolved in 30 ml of water was added to an aqueous solution in which 10.00 g of dried eicosapentaenoate was dissolved in 200 ml of water over 30 minutes. The precipitated product was taken out and dried in vacuo at 60 ° C. to yield 9.5 g of barium eicosapentaenoate (EPA-Ba).

(Sodium docosahexaenoate)

Sodium docosahexaenoate (DHA-Na) is obtained in the same manner as described above except that docosahexaenoic acid ethyl ester (manufactured by Kyowa Technos Co., Ltd.) is used in place of eicosapentaenoic acid ethyl ester.

(Eleostearic acid)

500 g of paulownia oil is added to a 3-liter flask equipped with a cooling tube, a dropping funnel and a nitrogen introduction line, and nitrogen-substituted. After heating up to 100 degreeC, 723g of 20% potassium hydroxide aqueous solution is added dropwise. After completion of the dropwise addition, stirring was carried out at 100 ° C. for 4 hours. After cooling the reaction solution, 1 kg of toluene is added to dissolve it, and 260 g of hydrochloric acid and 260 g of pure water are added to make a homogeneous solution. After concentrating the solution to 496.7 g, the precipitated solid was transferred to a separate flask, hexane was added and stirred at 70 ° C. for 3 hours to obtain a uniform solution. After cooling this solution to 0 degreeC, solid is precipitated by standing overnight. The precipitated solid was suction filtered and washed twice with 1 liter of cold hexane. Subsequently, 233 g of eleostearic acid is obtained by vacuum drying at room temperature.

(Sodium stearate)

116.5 g of eleostearic acid and 16.73 g of sodium hydroxide prepared by the above method were added to a 3-liter flask equipped with a cooling tube, a dropping funnel, and a nitrogen introduction line, followed by nitrogen replacement, and then 155 g of pure water was added thereto. Stir for 3 hours at < RTI ID = 0.0 > The resulting solid is suction filtered and washed three times with 2 liters of pure water. Subsequently, 107 g of sodium leostearate is obtained by vacuum drying at 80 deg.

(Iron linoleate)

25.13 g of linolenic acid, 3.61 g of sodium hydroxide (dissolved in 10 g of water) and 100 ml of toluene are mixed, and after azeotropic dehydration for 2 hours, the toluene is distilled off. The product obtained is dried under reduced pressure and 21.55 g of sodium linoleate is obtained. 10.00 g of such sodium linoleate and 90 g of water are mixed under a nitrogen atmosphere, and the temperature is raised in a bath having a bath temperature of 50 ° C. To this mixture, an aqueous solution in which 4.63 g of ferrous sulfate (hexahydrate) was dissolved in 18 ml of water (end of nitrogen bubbling) was added over 30 minutes. When an aqueous solution is added, the precipitate becomes black with time, and becomes dark black 30 minutes after the ferrous sulfate aqueous solution is added. This is considered to be because iron (II) is oxidized to iron (III). As described above, in the comparative sample using the transition metal salt of linolenic acid, oxidative deterioration is severe, and thus there is a problem of poor handling and coloring.

(Manganese Linoleate)

Manganese linoleate is obtained in the same manner as above except that manganese sulfate (pentahydrate) is used instead of ferrous sulfate (hexahydrate).

(Production of Samples 1 to 3)

7 g of various metal salts of linolenic acid synthesized by the above method, 0.59 g of cobalt stearate (about 800 ppm of Co) and 63 g of EVOH are dry blended and then melt blended at 200 ° C. for 5 minutes. Melt blending is carried out while purging the atmosphere with nitrogen. The various compositions obtained are then heated to 200 ° C. to press and a film of about 200 μm thick is obtained. In this manner, a film containing calcium linoleate (sample 1), a film containing sodium linoleate (sample 2) and a film containing aluminum linoleate (sample 3) are produced. When the cross sections of these films were observed with a transmission electron microscope, various metal salts of linolenic acid were dispersed in a particle diameter of about 1 µm, and the dispersibility was good. In particular, aluminum linoleate is more finely dispersed, and dispersibility is very good.

(Production of samples 4 to 6)

A film containing calcium eicosapentaenoate (sample 4), eicosapentaenoic acid, in the same manner as Samples 1 to 3, except that 7 g of various metal salts of eicosapentaenoic acid were used instead of 7 g of linolenic acid salts. A film containing sodium (sample 5) and a film containing barium eicosapentaenoate (sample 6) were produced. The cross sections of these films (thickness of about 200 µm) were observed with a transmission electron microscope. As a result, the metal salts of eicosapentaenoic acid were dispersed in a particle diameter of about 1 µm, and dispersibility was good.

(Production of sample 7)

A film of Sample 7 (thickness about 200 μm) was prepared in the same manner as Samples 1 to 3, except that 7 g of sodium docosahexaenoate was used instead of 7 g of linoleate. The cross section of such a film was observed with a transmission electron microscope, and sodium docosahexanoate was dispersed in a particle diameter of about 1 µm, and the dispersibility was good.

(Production of sample 8)

A film of Sample 8 (thickness about 200 μm) was produced in the same manner as Samples 1 to 3, except that 7 g of sodium oleate was used instead of 7 g of linoleate. The cross section of such a film was observed with a transmission electron microscope, and sodium oleate was dispersed in a particle diameter of about 1 µm, and dispersibility was good.

(Production of sample 9)

A film of Sample 9 (thickness of about 200 μm) was prepared in the same manner as Sample 5, except that 63 g of polycaproamide (nylon-6, manufactured by Ubego Sangyo Co., Ltd., trade name: 1030B) was used instead of 63 g of EVOH. . The cross section of such a film was observed with a transmission electron microscope. As a result, the metal salt of eicosapentaenoic acid was dispersed in a particle diameter of about 1 µm, and the dispersibility was good.

(Production of sample 10)

A film of Sample 10 (thickness of about 200 μm) was produced in the same manner as Sample 5, except that 63 g of polyacrylonitrile (trade name: Varex 1000) was used instead of 63 g of EVOH. do.

(Production of sample 11)

The film of Sample 11 (thickness about 200 μm) was prepared in the same manner as in Sample 5, except that 63 g of polyvinyl chloride (manufactured by Sekisui Chemical Co., Ltd., product name: Esmeica V6142E) was used instead of 63 g of EVOH. To make.

(Production of sample 12)

The same method as Sample 5, except that titanium dioxide powder (manufactured by Nippon Aerogel Co., Ltd., product name: P-25 (including 73.5% anatase type and 26.5% rutile type)) was used instead of cobalt stearate. To prepare a film of Sample 12. Specifically, 7 g of eicosapentaenoate, 0.70 g of titanium dioxide, and 63 g of EVOH are dry blended, followed by melt blending at 200 ° C. for 5 minutes. The resulting composition is then heated to 200 ° C. and pressed to obtain a film of about 200 μm thickness (sample 12.) The cross section of this film was observed by transmission electron microscopy. Sodium sapentanoate is dispersed in a particle diameter of about 1 μm, and dispersibility is good.

(Production of sample 13)

40.5 g of a water / methanol (= 30/70 wt%) mixed solution and 4.5 g of EVOH were collected in a beaker, heated to 80 ° C. with good stirring, to prepare an EVOH solution of 10 wt% concentration. To this solution, 0.5 g of sodium eicosapentaenoate and 0.05 g of N-hydroxyphthalic acid imide (NHPI) are added, and the solution is uniformly dissolved at room temperature under a nitrogen atmosphere. The obtained solution is applied by bar coating on a commercially available PET film subjected to corona treatment, and then the solvent is removed by a vacuum dryer. In this way, a film (sample 13) in which a coating film having a thickness of about 10 μm is formed is obtained. When the cross section of the coating film part of such a film was observed with the transmission electron microscope, sodium eicosapentaate disperse | distributed to the particle diameter of about 1 micrometer, and dispersibility is favorable.

(Production of sample 14)

A film of Sample 14 was prepared in the same manner as in Sample 13, except that cobalt acetate was used instead of N-hydroxyphthalimide. Specifically, 40.5 g of a water / methanol (= 30/70 wt%) mixed solution and 4.5 g of EVOH were collected in a beaker, superheated to 80 ° C. with good stirring, and an EVOH solution having a concentration of 10 wt% was prepared. 0.5 g of sodium eicosapentaate and 0.85 g of cobalt acetate (amount of Co is about 400 ppm) were added to this solution, and it was dissolved uniformly at room temperature under a nitrogen atmosphere. The obtained solution is applied by bar coating on a commercially available PET film subjected to corona treatment, and then the solvent is removed by a vacuum dryer. In this way, a film (sample 14) on which a coating film having a thickness of about 10 μm is formed is obtained. When the cross section of the coating film part of such a film was observed with the transmission electron microscope, sodium eicosapentaate disperse | distributed to the particle diameter of about 1 micrometer, and dispersibility is favorable.

(Comparative Sample 1)

A film of Comparative Sample 1 (thickness about 200 μm) was prepared in the same manner as Samples 1 to 3, except that 7 g of linolenic acid was used instead of 7 g of linolenic acid salt. The cross section of such a film was observed with a transmission electron microscope. As a result, linolenic acid was dispersed in a particle diameter of 5 mu m or more, and the dispersibility was not good.

(Comparative Sample 2)

A film of Comparative Sample 2 (thickness about 200 μm) was prepared in the same manner as Samples 1 to 3, except that 7 g of eleostearic acid was used instead of 7 g of linoleate. The cross section of the film was observed with a transmission electron microscope. As a result, eleostearic acid was dispersed in a size having a particle diameter of 5 µm or more, and dispersibility was not good.

(Comparative Sample 3)

A film of Comparative Sample 2 (thickness of about 200 μm) was prepared in the same manner as Samples 1 to 3, except that 63 g of low density polyethylene (Novtek LA320) manufactured by Nippon Polyethylene Co., Ltd. (trade name: Novatec LA320) was used instead of 63 g of EVOH. . The cross section of such a film was observed with a transmission electron microscope, and the linolenic acid salt was dispersed in a size having a particle diameter of 5 µm or more, and the dispersibility was not good.

(Comparative Samples 4 and 5)

The films of Comparative Samples 4 and 5 were prepared in the same manner as Samples 1 to 3, except that iron linoleate or manganese linoleate was used instead of sodium linoleate. However, both samples are also highly colored, and a beautiful film cannot be produced.

[Evaluation of Oxygen Absorption Capacity]

(Evaluation of Oxygen Absorbability of Samples 1-3 and Comparative Sample 1)

1.0 g of the films of Samples 1 to 3 and Comparative Sample 1 are respectively sealed in (1) 50% RH at 23 ° C. or (2) 100% RH at 23 ° C. in a 260 cc bottle. . In addition, 1.0 g of the film, respectively, (3) at room temperature of 50% RH at 60 ° C. or (4) at room temperature of 100% RH at 60 ° C., was simultaneously added to a bottle of capacity 260 cc with 5 cc of water to seal the bottle. And the oxygen concentration in a bottle is measured every fixed period, and the quantity of oxygen absorbed is computed. At this time, the bottles of the conditions of (1) and (2) are stored at 23 degreeC, and the bottles of (3) and (4) are stored at 60 degreeC. The measurement results are shown in FIGS. 1 to 4. As shown in Figures 1 to 4, Sample 2 using sodium linoleate has a low oxygen absorption capacity under high humidity. Sample 1 using calcium linoleate is highly affected by temperature / humidity in the measurement, but achieves a maximum oxygen absorption of 31 cc / g (after 38 days at 60 ° C. and 100% RH). Sample 3 using aluminum linoleate is largely affected by the temperature / humidity as measured in Sample 1, but achieves up to 30 cc / g (after 38 days at 60 ° C. and 100% RH) oxygen absorption. On the other hand, the film of Comparative Sample 1 shows little oxygen absorption.

(Evaluation of Oxygen Absorbability of Samples 4 to 8 and Comparative Sample 2)

The oxygen absorption capacity of the films of Samples 4 to 8 and Comparative Example 2 is evaluated by the same method as above. The measurement result of the samples 4-6 is shown to FIGS. 5-8. The measurement result of sample 7 is shown in FIG. 9. The measurement result of the sample 8 and the comparative sample 2 is shown to FIGS. 10-13.

(Evaluation of Oxygen Absorbing Capacity of Samples 9 to 14 and Comparative Sample 3)

The oxygen absorption capacity of the films of Samples 9 to 14 and Comparative Sample 3 is evaluated according to the same method as above. As a result, any sample shows oxygen absorption.

(Evaluation of Oxygen Absorbing Capacity of Comparative Sample 3)

The oxygen absorption ability of the film of Comparative Sample 3 is evaluated according to the same method as above. As a result, the film of Comparative Sample 3 shows oxygen absorption.

(Evaluation of Oxygen Absorbability of Comparative Samples 4 and 5)

The oxygen absorption ability of the films of Comparative Samples 4 and 5 was evaluated according to the same method as above. As a result, since both samples have poor thermal stability, coloring is severe and hardly exhibits oxygen absorption.

(Odor evaluation)

Samples 1 to 8 and 1 g of films of Comparative Samples 1 to 3 are precisely weighed, wound up in rolls after 5 hours of sheet molding, and placed in a bottle of 85 ml of internal capacity filled with air at 23 ° C. and 50% RH. 1 ml of water is added to the bottle, and the inlet of the bottle is sealed using a multilayer sheet containing an aluminum layer and an epoxy resin, and then left at 60 ° C. for 2 weeks. Subsequently, five panelists evaluate the head space gas of the sample. As a result, the fish smells in Comparative Samples 1 and 3, and the rubber smell in Comparative Sample 2. On the other hand, Samples 1 to 8 have a lower odor than the comparative samples.

(Evaluation of volatilization inhibitory effect)

In the same manner as in Samples 1 to 8 and Comparative Sample 1, various metal salts or linolenic acid, cobalt stearate and EVOH were dry blended, followed by melt blending at 200 ° C. for 5 minutes. Melt mixing is carried out while depressurizing the inside of the mixing apparatus by degassing by using a vacuum pump at the vent to remove impurities. A film is produced using the composition thus prepared, and the oxygen absorption capacity is measured. As a result, the comparative sample 1 using linolenic acid volatilizes linolenic acid in a vent part at the time of melt-blending, and does not show sufficient oxygen absorption ability. On the other hand, there is no such volatilization in the metal salt, and the sample using the metal salt exhibits the same oxygen absorption capacity as that produced by melt blending while purging with nitrogen.

Dissolution Test

A 20-micrometer-thick stretched polypropylene film (OP- # 20 U-1 manufactured by Tocelo Co., Ltd.) having a thickness of 20 µm is laminated on both surfaces of the films of Samples 1 to 8 and Comparative Samples 1 and 2 using an adhesive. As the adhesive, a mixture of a urethane adhesive (Toyo Moton, trade name: AD335A), a curing agent (Toyo Motone, trade name: Cat-10), and a toluene / methyl ethyl ketone mixed solution (weight ratio 1: 1) is used. In this way, a laminated sheet having a laminated structure of a stretched polypropylene film layer / urethane adhesive layer / resin composition layer (oxygen absorbent film layer) / urethane-based adhesive layer / stretched polypropylene film layer is produced.

Subsequently, two obtained laminated sheets are piled up and heat-sealed, and the pouch of 30 cm x 30 cm is produced. Put water inside the pouch. This pouch is stored for 60 days at 30 ° C. under an atmosphere of 80% RH, and then the water inside the pouch is analyzed by gas chromatography mass spectrometry (GC-MS). As a result, in the case of comparative sample 1 using linolenic acid, elution of linolenic acid is confirmed, and in the case of comparative sample 2 using eleostearic acid, elution of eleostearic acid is confirmed. On the other hand, such elution is not confirmed in the sample using various metal salts.

The configuration of each sample is shown in Table 1.

Unsaturated carboxylic acid Oxygen absorption promoter Suzy Sample 1 Linolenic Acid Ca Stearic acid Co EVOH Sample 2 Linolenic acid Na Stearic acid Co EVOH Sample 3 Linolenic Acid Al Stearic acid Co EVOH Sample 4 EPA-Ca Stearic acid Co EVOH Sample 5 EPA-Na Stearic acid Co EVOH Sample 6 EPA-Ba Stearic acid Co EVOH Sample 7 DHA-Na Stearic acid Co EVOH Sample 8 Eleostearic acid Na Stearic acid Co EVOH Sample 9 EPA-Na Stearic acid Co Nylon-6 Sample 10 EPA-Na Stearic acid Co Polyacrylonitrile Sample 11 EPA-Na Stearic acid Co Polyvinyl chloride Sample 12 EPA-Na Titanium dioxide EVOH Sample 13 EPA-Na NHPI EVOH Sample 14 EPA-Na Acetate Co EVOH Comparison sample 1 Linolenic acid Stearic acid Co EVOH Comparison sample 2 Eleostearic acid Stearic acid Co EVOH Comparison sample 3 Linolenic acid Na Stearic acid Co Polyethylene Comparison sample 4 Linolenic acid Fe Stearic acid Co EVOH Comparative Sample 5 Linolenic acid Mn Stearic acid Co EVOH

The evaluation results of each sample are shown in Table 2.

Oxygen absorption capacity stink Volatilization inhibitory effect Dissolution test Dispersibility Sample 1 There lowness No volatility No dissolution About 1㎛ Sample 2 There lowness No volatility No dissolution About 1㎛ Sample 3 There lowness No volatility No dissolution About 1㎛ Sample 4 There lowness No volatility No dissolution About 1㎛ Sample 5 There lowness No volatility No dissolution About 1㎛ Sample 6 There lowness No volatility No dissolution About 1㎛ Sample 7 There lowness No volatility No dissolution About 1㎛ Sample 8 There lowness No volatility No dissolution About 1㎛ Sample 9 There - - - About 1㎛ Sample 10 There - - - - Sample 11 There - - - - Sample 12 There - - - About 1㎛ Sample 13 There - - - About 1㎛ Sample 14 There - - - About 1㎛ Comparison sample 1 None at all Fish smell Volatilized There is dissolution 5 ㎛ or more Comparison sample 2 There Rubber smell - There is dissolution 5 ㎛ or more Comparison sample 3 There Fish smell - - 5 ㎛ or more Comparison sample 4 None at all - - - - Comparative Sample 5 None at all - - - -

In addition, dispersibility is evaluated by the particle diameter of carboxylic acid or carboxylate dispersed in resin. Smaller particle diameters indicate better dispersibility. As described in the result of the comparative sample 3, when polyethylene which is not a gas barrier resin is used as resin, the dispersibility of an oxygen absorption promoter falls. This is considered to be because hydrocarbon-based polymers, such as polyethylene, have inferior affinity with the carboxylate which has an oxygen containing functional group compared with gas barrier resin.

As shown in Table 2, in Comparative Samples 1 and 2 using unsaturated carboxylic acids, fish odor or rubber odor occurs. In Comparative Samples 1 and 2, the dispersibility of unsaturated carboxylic acids is low. Equally, fish odor occurs in Comparative Sample 3 using polyethylene as the resin. In Comparative Samples 4 and 5 using a transition metal salt as the unsaturated carboxylate, coloration is severe and oxygen absorption ability is low.

The present invention can be applied to an oxygen absorbent composition and a packaging material using the same. In particular, it is suitably used as a packaging material for articles having a large influence of deterioration due to oxygen, for example, food, medicine, medical equipment, machine parts, clothing and the like.

Claims (8)

Containing a gas barrier resin, a salt of an unsaturated carboxylic acid dispersed in the gas barrier resin, and an oxygen absorption promoter, The cation constituting the salt of the unsaturated carboxylic acid is a cation of at least one element selected from the group consisting of alkali metals, alkaline earth metals and aluminum, The oxygen absorption promoter is at least one selected from the group consisting of transition metal salts, radical generators and photocatalyst particles, The oxygen absorbent composition whose molecular weight of unsaturated carboxylic acid is 3,000 or less. The unsaturated carboxylic acid according to claim 1, wherein the unsaturated carboxylic acid is palmitoleic acid, oleic acid, linoleic acid, linolenic acid, arachidonic acid, parinaric acid, dimer acid, docosahexaenoic acid, eicosapentaenoic acid, fish oil fatty acid, linseed oil At least one selected from the group consisting of fatty acids, soybean oil fatty acid, paulownia oil fatty acid, sugar oil fatty acid, sesame oil fatty acid, cottonseed oil fatty acid, rapeseed oil fatty acid and tall oil fatty acid. The oxygen absorbing composition according to claim 1, wherein the gas barrier resin comprises a polyvinyl alcohol-based resin. A packaging material comprising a portion made of an oxygen absorbent composition, The oxygen absorbent composition comprises a gas barrier resin, a salt of an unsaturated carboxylic acid dispersed in a gas barrier resin and an oxygen absorption promoter, The cation constituting the salt of the unsaturated carboxylic acid is a cation of at least one element selected from the group consisting of alkali metals, alkaline earth metals and aluminum, The oxygen absorption promoter is at least one selected from the group consisting of transition metal salts, radical generators and photocatalyst particles, The packaging material whose molecular weight of unsaturated carboxylic acid is 3,000 or less. The unsaturated carboxylic acid according to claim 4, wherein the unsaturated carboxylic acid is palmitoleic acid, oleic acid, linoleic acid, linolenic acid, arachidonic acid, perinaric acid, dimer acid, docosahexaenoic acid, eicosapentaenoic acid, fish oil fatty acid, linseed oil fatty acid, soybean oil fatty acid. Packaging material which is at least one selected from the group consisting of paulownia oil fatty acid, sugar oil fatty acid, sesame oil fatty acid, cottonseed oil fatty acid, rapeseed oil fatty acid and tall oil fatty acid. The packaging material according to claim 4, wherein the gas barrier resin comprises a polyvinyl alcohol resin. The packaging material according to claim 4, wherein the portion made of the oxygen absorbent composition is a layer made of the oxygen absorbent composition. 8. A packaging material according to claim 7, comprising a layer made of an oxygen absorbent composition and another layer laminated to the layer.

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