JPH11314305A - Oxygen absorbing packaging material and food packaging material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an oxygen absorbing packaging material retaining the oxygen absorbability for a longer period of time and having gas barrier properties suppressing the deterioration of the contents housed in a packaging material effectively. SOLUTION: An oxygen absorbing packaging material is formed by using a laminate obtained by laminating a gas barrier layer comprising a resin compsn. containing an inorg. laminar compd. on a base material. At this time, it is preferable to laminate an anchor layer between the base material and the gas barrier layer. Oxygen absorbability is imparted to the inner surface of the oxygen absorbing packaging material, that is, the gas barrier layer thereof. As a method for imparting oxygen absorbability, it is preferable to use a method sealing an oxygen scavenger in the gas barrier layer.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an oxygen-absorbing packaging material having excellent gas barrier properties against oxygen, and itself having an oxygen absorbing property, and a food packaging material provided with the oxygen-absorbing packaging material. It is about.

[0002]

2. Description of the Related Art In many cases, foods, pharmaceuticals, electronic materials, and the like are deteriorated when they come into contact with oxygen. Therefore, oxygen is cut off as much as possible by packaging. For example, among foods, particularly, prepared foods, processed livestock products, processed marine products, etc., are required to have freshness, but when these foods come into contact with oxygen, the freshness of the foods is significantly deteriorated. Will decrease.

[0003] Specifically, when food comes in contact with oxygen, molds and aerobic bacteria proliferate, causing the food to spoil, and fats and oils such as unsaturated fatty acids and nutrients are oxidized. Species fade with oxidation etc.,
This leads to a decrease in quality such as. Therefore, the packaging of foods and the like needs to be made so as to block oxygen as much as possible.

Therefore, as a packaging material for effectively blocking oxygen, conventionally, an inner surface of the packaging material, that is, a surface which comes into contact with the content side when the content such as food is wrapped,
An oxygen-absorbing packaging material having oxygen-absorbing properties is used.

[0005] When such an oxygen-absorbing packaging material is used, it is possible to absorb the oxygen remaining inside the packaging material after packaging, so that there is almost no residual oxygen in the packaging material. . Here, the packaging material needs to have a certain gas barrier property. In other words, if the gas barrier property of the packaging material itself is low, oxygen will permeate through the packaging material from the outside air, and oxygen absorption will deteriorate over time,
This is because it becomes difficult to store for a longer period of time.

[0006] The above-mentioned evaluation as the gas barrier property can be performed based on the oxygen permeability. Usually, the gas barrier property of the packaging material used for the oxygen-absorbing packaging material is not more than 20 mL / m ² · day · atm in terms of oxygen permeability.

[0007]

However, the gas barrier properties of conventional packaging materials are not yet sufficient. In other words, the above oxygen permeability or less (20 mL / m ² · day ·
Under the condition (atm or less), it is not possible to effectively prevent oxygen from entering the inside of the packaging material. Therefore, in the conventional oxygen-absorbing wrapping material, suppression of the decrease in the oxygen absorbency of the packaging material itself with time becomes insufficient, and the oxygen absorbency cannot be maintained for a long time.

[0008] As a result, the packaging material itself eventually loses its oxygen absorbency, and the contents come into contact with external oxygen, and the contents cannot be protected for a long time. Will be invited.

[0009] Therefore, the oxygen-absorbing packaging material has an unprecedentedly high gas barrier property in order to maintain oxygen absorption for a longer period of time and to suppress deterioration of the contents stored in the packaging material. Was required.

[0010]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies to solve the above problems, and as a result, have obtained a packaging material using a laminate having a gas barrier layer made of a resin composition having an inorganic layered compound. However, when oxygen is given to the inner surface of the packaging material (that is, the surface that comes into contact with the contents when the packaging material is packaged), oxygen is effectively blocked as compared with a packaging material having a simple gas barrier property. The inventors have found that the deterioration of the contents can be significantly suppressed and the contents can be stored for a long period of time, and the present invention has been completed.

That is, in order to solve the above-mentioned problems, the oxygen-absorbing wrapping material of the present invention stores and wraps contents and has an oxygen-absorbing property for absorbing oxygen in contact with the contents. The packaging material includes a laminate having a gas barrier layer made of a resin composition having an inorganic layered compound, and the surface of the laminate in contact with the contents is provided with the oxygen-absorbing property. It is characterized by.

According to the above configuration, since the packaging material is formed from the laminate having the gas barrier layer, very excellent gas barrier properties can be realized, and the packaging material itself has oxygen absorption. Therefore, oxygen does not enter the inside from the outside air. In addition, since oxygen absorption is provided on the inner side when viewed from the gas barrier layer, that is, on the side in contact with the stored contents, oxygen entering from outside air reduces oxygen absorption. Therefore, the oxygen absorption is maintained for a longer time than before. As a result, the combined use of the excellent gas barrier properties and the long-term oxygen absorption properties makes it possible to very effectively suppress the deterioration of the contents due to oxygen, as compared to a packaging material having merely gas barrier properties.

It is preferable that the oxygen absorbing property is provided by enclosing a deoxidizer between at least the gas barrier layer and the surface of the laminate in contact with the contents.
As the oxygen scavenger, for example, an iron or organic oxygen absorber can be suitably used.

The oxygen-absorbing packaging material is a vertical pillow packaging bag,
Horizontal pillow packaging bag, gusset packaging bag, 3-side seal packaging bag,
4-side sealed packaging bag, pair of vacuum and compressed air molded container and lid,
At least one selected from a pair of an injection or press-molded container and a lid, a squeeze bottle, a standing pouch, a bag-in-box, a paper carton container, and a bottle
It is preferably processed into a different packaging shape.

That is, by adopting any one of the above-described forms of the oxygen-absorbing packaging material, packaging according to the contents becomes possible, and deterioration of the contents due to oxygen can be more effectively suppressed.

In the oxygen-absorbing packaging material according to the present invention, the laminate preferably further has at least one metal or metal oxide layer. The formation of the metal or metal oxide layer is not particularly limited, but is preferably formed by an evaporation method. By forming the metal or metal oxide layer, the gas barrier properties of the contents can be improved and the contents can be shielded from light, so that the deterioration of the contents can be further suppressed.

The oxygen-absorbing packaging material according to the present invention preferably has at least one polyolefin resin layer, and more preferably at least one biaxially stretched film layer. By forming these layers, the gas barrier properties of the packaging material can be further improved.

The oxygen permeability of the oxygen-absorbing packaging material according to the present invention is preferably 1 mL / m ² · day · atm or less, more preferably 0.1 mL / m ² · day · atm or less. more preferably, 0.05mL / m ² · day ·
More preferably, it is atm or less. When the oxygen permeability is within this range, the oxygen absorbency imparted to the packaging material can be maintained for a longer period.

In the oxygen-absorbing packaging material according to the present invention, the inorganic layered compound is preferably swelled and cleaved in a dispersion medium, and the gas barrier layer is formed by subjecting a mixture of a resin composition having an inorganic layered compound to high-pressure dispersion treatment. It is preferably obtained by the following method. The pressure conditions for the high-pressure dispersion treatment are as follows:
It is preferably at least 100 kgf / cm ² ,
0 kgf / cm ² or more, more preferably 1 kgf / cm ² or more.
It is particularly preferred that it is not less than 000 kgf / cm ² .

The aspect ratio of the inorganic layered compound is as follows:
It is preferably in the range of 50 to 5000, and more preferably in the range of 300 to 2000.

The above resin composition preferably contains a high hydrogen bonding resin. At this time, the weight ratio between the inorganic layered compound and the high hydrogen bonding resin is (1/100) to
(100/1), preferably (1/1).
More preferably, it is in the range of 20) to (10/1). Further, the high hydrogen bonding resin preferably has a molar percentage of hydrogen bonding group or ionic group per unit weight of the resin of 30% or more and 50% or less. It is preferable that the product is a polysaccharide, a polysaccharide, or an ethylene-vinyl alcohol copolymer and a modified product thereof.

By providing these components, the gas barrier properties of the oxygen-absorbing packaging material can be further improved, and the oxygen-absorbing property can be maintained for a long period of time, so that the deterioration of the contents can be more effectively suppressed. be able to.

A food packaging material according to the present invention is characterized by including an oxygen-absorbing packaging material having the above-described configuration. Therefore, it is possible to provide a food packaging material which can be suitably used particularly for packaging of fresh foods and the like which are easily deteriorated rapidly by oxygen.

[0024]

FIG. 1 shows an embodiment of the present invention.
The following is a description based on FIG.
The oxygen-absorbing packaging material according to the present invention includes a gas barrier layer made of a resin composition having an inorganic layered compound, and further has an oxygen-absorbing property between the surface in contact with the contents and the gas barrier layer. Configuration.

The inorganic layered compound used in the gas barrier layer is an inorganic compound having a layered structure in which unit crystal layers are stacked on each other, and when cleaved, the particle size is 5 μm or less, and the aspect ratio is gas barrier. The property is not particularly limited as long as the aspect ratio is in the range of 200 to 3,000, more preferably in the range of 200 to 3,000.

If the aspect ratio is less than 50, the gas barrier property is not sufficient, and if the aspect ratio is more than 5000, it is technically difficult and economically expensive. Further, when the particle size is 3 μm or less, the transparency becomes better, and when the particle size is 1 μm or less, it is more preferable for applications in which transparency is important.

Specific examples of the above-mentioned inorganic layered compound include graphite, phosphate derivative-type compounds (zirconium phosphate compounds, etc.), chalcogenides, clay minerals and the like. Here, the “chalcogen compound” includes a group IV (Ti, Zr, Hf) and a group V (V, Nb, T).
a) and dichalcogenides of group VI (Mo, W), wherein the compound is of the formula MX ₂ (M is the above element, X is the chalcogen (S,
Se, Te). ).

The particle size of the above-mentioned inorganic layered compound means a particle size obtained by a diffraction / scattering method in a dispersion medium. It is extremely difficult to measure the true particle size in the gas barrier layer.
In the case where the dispersion medium of the same kind as the dispersion medium used in the scattering method is sufficiently swollen and cleaved to be combined with the resin used for the gas barrier layer, the cleaved unit crystal layer in the resin 32 of the gas barrier layer 3 shown in FIG. The particle size of 31 can be considered to correspond to the particle size of the cleaved inorganic layered compound in the dispersion medium.

[Method for Determining Average Particle Diameter] The method for determining the average particle diameter of particles in a liquid includes a method based on a diffraction / scattering method, a method based on a dynamic light scattering method, a method based on a change in electric resistance, and after photographing in a liquid microscope. A method by image processing or the like is possible.

In the dynamic light scattering method, when the resin and the particles coexist, the apparent liquid viscosity is different from that of the pure dispersion medium, so it is difficult to evaluate the method. There is a problem of resolution in the method using image processing after photographing in a submerged microscope, and each method is difficult to use.

According to the diffraction / scattering method, when a resin solution, for example, a resin aqueous solution has substantially little scattering (transparency), and scattering derived from particles is dominant, particles are dispersed regardless of the presence or absence of the resin. It is preferable because information on only the particle size distribution can be obtained.

[Measurement of Average Particle Size by Diffraction / Scattering Method] The particle size distribution and average particle size measurement by the diffraction / scattering method are carried out by irradiating a dispersion obtained by dispersing a swollen and cleaved inorganic layered compound in an aqueous dispersion medium. The diffraction / scattering pattern obtained when the light is allowed to pass through is calculated by using the Mie scattering theory or the like to calculate the most consistent particle size distribution of the pattern.

As a commercially available device, a particle size measuring device (LS230, LS200, L
S100, manufactured by Coulter Co., Ltd.), laser diffraction particle size distribution analyzer (SALD2000, SALD2000A, S
ALD3000, manufactured by Shimadzu Corporation) Laser diffraction / scattering type particle size distribution analyzer (LA910, LA700, LA5)
00, manufactured by Horiba and Microtrack SP
A, Microtrack FRA, manufactured by Nikkiso Co., Ltd.).

[Aspect Ratio Measurement Method] The aspect ratio (Z) is a ratio obtained from the relationship of Z = L / a. Here, L is the particle diameter (volume-based median diameter) of the inorganic layered compound in the dispersion obtained by the particle diameter measurement method by the above-mentioned diffraction / scattering method, and a is the cleaved unit shown in FIG. This is the unit thickness of the crystal layer 31. The “unit thickness a” is a value determined based on the result of independently measuring the thickness of the inorganic layered compound by a powder X-ray diffraction method described later or the like.

More specifically, as schematically shown in the graph of FIG. 2 in which the horizontal axis represents 2θ and the vertical axis represents the intensity of the X-ray diffraction peak, the lowest diffraction angle of the observed diffraction peaks is shown. From the angle θ corresponding to the peak, the Bragg equation (nλ = 2Dsi
The interval determined based on nθ, n = 1, 2, 3,... is defined as “unit thickness a” (for details of the powder X-ray diffraction method, for example, see “ Guide (a) ”, page 69 (1985) published by Kagaku Dojinsha).

When the resin composition corresponding to the gas barrier layer 3 obtained by removing the dispersion medium from the dispersion is subjected to powder X-ray diffraction, usually the plane spacing of each of the dispersed inorganic layered compounds in the resin composition is obtained. Can be obtained as the surface distance d shown in FIG.

More specifically, as shown in the graph of FIG. 3 in which the horizontal axis indicates 2θ and the vertical axis indicates the intensity of the X-ray diffraction peak, the diffraction corresponding to the above “unit thickness a” is shown. Of the diffraction peaks observed at a lower angle (larger interval) than the peak position, the interval corresponding to the peak at the lowest angle is defined as “plane interval d” (a <d).

As schematically shown in the graph of FIG. 4, when it is difficult to detect a peak corresponding to the above-mentioned "surface distance d" by overlapping with a halo (or background), the lower angle side than 2θd is detected. The area of the portion excluding the baseline is set as the peak corresponding to the “surface distance d”.
Here, “θd” is a diffraction angle corresponding to “(unit thickness a) + (width of single resin chain)” (for details of the method of calculating the surface distance d, see, for example, Shuichi Iwami et al. Ed., "Encyclopedia of Clay", p. 35 or less and p. 271 or less, 1985
Year, see Asakura Shoten Co., Ltd.).

Normally, the difference between the above-mentioned surface distance d and “unit thickness a”, that is, the value of k = (da) (when converted into “length”) constitutes the resin composition. It is equal to or greater than the width of a single resin chain [k = (da) ≧ width of a single resin chain]. Such “width of a single resin chain” can be determined by simulation calculation or the like (for example, “Introduction to Polymer Chemistry”, pp. 103-110,
1981, see Chemical Doujinshi), and in the case of polyvinyl alcohol, it is 4 to 5 angstroms (2 to 3 angstroms for water molecules).

It is extremely difficult to directly measure the "true aspect ratio" of the unit crystal layer 31 in the gas barrier layer 3. Although the above aspect ratio Z = L / a is not always equal to the “true aspect ratio” of the unit crystal layer 31 in the gas barrier layer 3, the aspect ratio Z is “true” for the following reason. It is reasonable to approximate the "aspect ratio".

There is a relation of a <d between the plane distance d of the resin composition obtained by the powder X-ray diffraction method and the “unit thickness a” obtained by the powder X-ray diffraction measurement of the inorganic layered compound alone. And the value of (da) is the value of resin 1 in the composition.
If the width of the main chain or more, in the resin composition,
The resin is inserted between the layers of each inorganic layered compound. Therefore, the unit crystal layer 31 in the gas barrier layer 3
Is approximated by the above “unit thickness a”, that is, the “true aspect ratio” of the unit crystal layer 31 in the gas barrier layer 3 is referred to as the “aspect ratio Z” in the dispersion of the inorganic layered compound. There is sufficient validity to approximate with.

As described above, although it is extremely difficult to measure the true grain size of the unit crystal layer 31 in the gas barrier layer 3, the unit crystal layer 31 in the resin 32 of the gas barrier layer 3 is extremely difficult.
Is the particle size of the dispersion liquid (resin / inorganic layered compound / dispersion medium)
Can be considered to correspond to the particle size L of the inorganic layered compound.

However, the particle diameter L in the dispersion obtained by the diffraction / scattering method is considered to be very unlikely to exceed the major axis Lmax of the inorganic layered compound, so that the true aspect ratio (Lmax / a) is low. The possibility that the ratio is lower than the “aspect ratio Z” used in the present invention (Lmax / a <Z) is theoretically considerably low.

From the above two points, it is considered that the definition Z of the aspect ratio used in the present invention has sufficient validity. In the present specification, “aspect ratio” or “particle size” means “aspect ratio Z” defined above or “particle size L determined by a diffraction / scattering method”.

From the viewpoint of easily giving a large aspect ratio, an inorganic layered compound having a property of swelling and cleaving in a dispersion medium is preferably used.

The swelling of the inorganic layered compound in the dispersion medium
The degree of "cleavage" can be evaluated by the following "swelling / cleavage" test. The swellability of the inorganic layered compound is
In the following swellability test, the swelling value is preferably about 5 or more (more preferably, about 20 or more). On the other hand, the cleavage property of the inorganic layered compound is preferably about 5 or more (and more preferably about 20 or more) in the cleavage test. In these cases, a liquid having a density smaller than the density of the inorganic layered compound is used as the dispersion medium. When the inorganic layered compound is a natural swellable clay mineral, it is preferable to use water as the dispersion medium.

<Swelling test> 100 mL of the dispersion medium was placed in a 100 mL measuring cylinder, and 2 g of the inorganic layered compound was added thereto.
Add slowly. After standing, the volume (mL) of the inorganic layered compound dispersed layer is read as the swelling value from the scale at the interface between the inorganic layered compound dispersed layer and the supernatant after 24 hours at 23 ° C. The larger the value, the higher the swelling property.

<Cleaving test> 30 g of an inorganic layered compound was slowly added to 1500 mL of a dispersion medium, and a disperser [DESPA MH-L, manufactured by Asada Tekko Co., Ltd., blade diameter 52 mm, rotation speed 3]
100 rpm, container capacity 3 L, distance 28 between bottom and blade
mm] at a peripheral speed of 8.5 m / sec for 90 minutes (23 ° C.), take 100 mL of the dispersion liquid, put it in a graduated cylinder and let stand for 60 minutes, and then, from the interface with the supernatant, the volume of the inorganic layered compound dispersed layer Read (mL) as cleavage value.

As the inorganic layered compound which swells and cleaves in the dispersion medium, a clay mineral which swells and cleaves in the dispersion medium is particularly preferably used. Such clay minerals are generally
On the top of the tetrahedral layer of silica, a two-layer structure with an octahedral layer with aluminum or magnesium as the central metal, and on an octahedral layer with a silica tetrahedral layer with aluminum or magnesium as the central metal Is classified into a type having a three-layer structure in which is narrowed from both sides. The former two-layer structure type includes a kaolinite group and an antigolite group, and the latter three-layer structure type includes a smectite group and a smectite group depending on the number of interlayer cations.
Vermiculite, mica and the like can be mentioned.

More specifically, these clay minerals include kaolinite, dickite, nacrite, halloysite, antigolite, chrysotile, pyrophyllite, montmorillonite, beidellite, nontronite, saponite, sauconite, stevensite, hectite. Light, tetrasilicyl mica, sodium teniolite, muscovite, margarite, talc, vermiculite, phlogopite, zansophyllite, chlorite and the like can be mentioned.

A clay mineral treated with an organic substance (hereinafter sometimes referred to as an organically modified clay mineral) can also be used as an inorganic layered compound. (Note that clay minerals treated with an organic substance are described in Asakura Shoten, See Clay Encyclopedia).

Among the above clay minerals, smectites, vermiculites and micas are preferable, and smectites are more preferable from the viewpoint of swelling or cleavage. Examples of the smectite group include montmorillonite, beidellite, nontronite, saponite, sauconite, stevensite, and hectorite.

The dispersion medium for swelling or cleaving the inorganic layered compound is, for example, water,
Examples include alcohols such as methanol, ethanol, propanol, isopropanol, ethylene glycol and diethylene glycol, dimethylformamide, dimethyl sulfoxide, and acetone, and more preferably alcohols such as water and methanol.

In the case of organically modified clay minerals, aromatic hydrocarbons such as benzene, toluene and xylene, ethers such as ethyl ether and tetrahydrofuran, ketones such as acetone, methyl ethyl ketone and methyl isobutyl ketone, n-pentane, Aliphatic hydrocarbons such as n-hexane and n-octane; halogenated hydrocarbons such as chlorobenzene, carbon tetrachloride, chloroform, dichloromethane, 1,2-dichloroethane and perchloroethylene; ethyl acetate; methyl methacrylate ( MMA), dioctyl phthalate (DOP), dimethylformamide,
Examples include dimethyl sulfoxide, methyl cellosolve, and silicone oil.

The oxygen-absorbing packaging material according to the present invention is not particularly limited as long as a resin composition containing the above-described inorganic layered compound can be formed into a layer to obtain a laminate having the gas barrier layer 3. For example, a method in which the above resin composition is molded into a film shape and bonded to a substrate may be used, or a coating liquid composed of a resin composition containing an inorganic layered compound is prepared, and this coating liquid is used as a base. A method of coating a material may be used.

The resin used in the method for molding the resin composition into a film is not particularly limited, and may be any resin that does not lower the gas barrier properties of the gas barrier layer 3. Here, polyvinylidene chloride-based resin and the like have excellent gas barrier properties and can be used as the above resin, but the resin contains chlorine,
In the case where the oxygen absorbing packaging material is incinerated after being used, it may impose a burden on the environment. In addition, as a method of molding the resin composition into a film shape, extrusion molding, calendering, or the like is preferably used, but is not particularly limited.

The oxygen-absorbing packaging material according to the present invention includes:
It can be molded into various shapes according to the contents to be stored and packaged. In this case, the method of laminating the gas barrier layer 3 is more resin-based than the method of first forming the film into a film and then laminating the substrate. It is preferable to use a method in which the composition is used as a coating liquid and the coating liquid is coated.

In the method of coating the coating liquid,
Since the gas barrier layer 3 can be laminated after the base material is first formed into a desired shape, the degree of freedom for forming the oxygen-absorbing packaging material according to the present invention can be further improved.

The resin contained in the above-mentioned coating liquid is not particularly limited. For example, polyolefin resin, polyester resin, amide resin, acrylic resin, styrene resin, acrylonitrile resin, cellulose resin,
Examples include a halogen-containing resin, a hydrogen bonding resin, a liquid crystal resin, a polyphenylene oxide resin, a polymethylene oxide resin, a polycarbonate resin, a polysulfone resin, a polyethersulfone resin, and a polyetheretherketone resin.

Preferred examples of the resin include resins containing a high hydrogen bonding resin having a hydrogen bonding group or an ionic group described below. The content of the hydrogen bonding group or the ionic group in the high hydrogen bonding resin (when both are included, the total amount of both) is usually 20 to 60 mol%, preferably 30 to 50 mol%. is there. The content of these hydrogen bonding groups and ionic groups can be measured, for example, by a nuclear magnetic resonance (NMR) technique (1H-NMR, 13C-NMR, etc.).

The above-mentioned hydrogen bonding group includes a hydroxyl group, an amino group, a thiol group, a carboxyl group, a sulfonic acid group,
Examples of the ionic group include a carboxylate group, a sulfonate ion group, a phosphate ion group, an ammonium group, and a phosphonium group. Among the hydrogen bonding groups or ionic groups, more preferred are a hydroxyl group, an amino group, a carboxyl group, a sulfonic acid group, a carboxylate group, a sulfonic acid ionic group, an ammonium group and the like.

Specific examples of the high hydrogen bonding resin include, for example, polyvinyl alcohol, an ethylene-vinyl alcohol copolymer having a vinyl alcohol fraction of 40 mol% or more, polysaccharides, polyacrylic acid and its esters, and polyacrylic acid. Sodium acid, polysulfonic acid, sodium polysulfonate, polyethyleneimine, polyallylamine and its quaternary ammonium salt, polyvinyl thiol, polyglycerin and the like. Among the above-mentioned resins, more preferred are polyvinyl alcohol and polysaccharides.

Here, the polyvinyl alcohol is a polymer obtained by, for example, hydrolyzing or transesterifying (saponifying) an acetic ester portion of a vinyl acetate polymer (ie, a copolymer of vinyl alcohol and vinyl acetate. And a polymer obtained by saponifying a vinyl trifluoroacetate polymer, a vinyl formate polymer, a vinyl pivalate polymer, a t-butyl vinyl ether polymer, a trimethylsilyl vinyl ether polymer, etc. (for details of polyvinyl alcohol). Is, for example, edited by the Poval Society, “The World of PVA”, 1992,
Nagano et al., “Poval” 1981
Year, see Polymer Publishing Association).

"Saponification" in polyvinyl alcohol
Is preferably 70% or more in terms of molar percentage, more preferably 85% or more, and particularly preferably 98% or more, a so-called fully saponified product. The degree of polymerization of polyvinyl alcohol is preferably from 100 to 5,000, more preferably from 200 to 3,000. Furthermore, the PVA referred to in the present invention may be modified with a small amount of a comonomer as long as the object of the present invention is not hindered.

The modified polyvinyl alcohol described above is
In the process of producing polyvinyl alcohol, a vinyl ester, particularly a vinyl acetate monomer, is copolymerized with another unsaturated monomer copolymerizable therewith. Examples of the other unsaturated monomers include olefins such as ethylene, propylene, α-hexene and α-octene, (meth) acrylic acid, crotonic acid, maleic acid (anhydride), fumaric acid, and itaconic acid. Sulfonic acid-containing monomers such as vinylsulfonic acid, styrenesulfonic acid, 2-acrylamido-2-methylpropanesulfonic acid and the like, and their alkali salts, dimethylaminoethyl (meta) )
Acrylate, diethylaminoethyl (meth) acrylate, trimethyl-2-(-1- (meth) acrylamide-1,1-dimethylethyl) ammonium chloride, trimethyl-3- (1- (meth) acrylamidopropyl) ammonium chloride, -Vinyl-2-ethylimidazole and other quaternizable cationic monomers,
Examples include styrene, alkyl vinyl ether, (meth) acrylamide, and others.

The ratio of these copolymer components is not particularly limited, but may be 5 to 5 units of vinyl alcohol.
0 mol% or less, preferably 30 mol% or less is preferable, and various forms obtained by any method such as random copolymerization, block copolymerization, and graft copolymerization are used as the form of copolymerization. .

Among these copolymers, a block copolymer in which a polycarboxylic acid component is copolymerized with a polyvinyl alcohol component is particularly preferably used. In the case where the polycarboxylic acid component is polymethacrylic acid, Particularly preferred. Further, the block copolymer is particularly preferably an AB block copolymer in which a polyacrylic acid chain is extended at one end of a polyvinyl alcohol chain, and the polyvinyl alcohol block component (a) Weight ratio of acrylic acid block component (b) (a) /
(B) is preferably 50/50 to 95/5,
In the case of 60/40 to 90/10, particularly preferable gas barrier properties are completed, and the bonding characteristics with the base material layer are remarkably completed. Further, among other modified forms, one particularly preferred form is a silyl group-modified polyvinyl alcohol resin composed of a saponified vinyl ester polymer modified with at least one compound having a silyl group in the molecule. is there.

The method for obtaining the modified polymer having such a composition is not particularly limited, but a silyl group may be added to a vinyl alcohol polymer such as polyvinyl alcohol or modified polyvinyl acetate obtained by a conventional method. Reacting a compound having a silyl group into the polymer, or activating the terminal of polyvinyl alcohol or a modified product thereof, and introducing an unsaturated monomer having a silyl group in the molecule to the terminal of the polymer. Various modification methods such as graft copolymerization of the unsaturated monomer to a vinyl alcohol polymer molecular chain, a copolymer comprising a vinyl ester monomer and an unsaturated monomer having a silyl group in the molecule. And saponifying it, or polymerizing a vinyl ester in the presence of a silyl group-containing mercaptan or the like and saponifying it. Introducing silyl groups into Runado end,
Various methods such as are effectively used.

The modified polyvinyl alcohol-based resin obtained by such various methods may be a resin having a silyl group in the molecule as a result, and the silyl group contained in the molecule may be an alkoxyl group or a silyl group. Those having a reactive substituent such as an acyloxyl group and a hydrolyzate of a silanol group or a salt thereof are preferable, and among them, a silanol group is particularly preferable.

Compounds having a silyl group in the molecule used to obtain these modified polyvinyl alcohol resins include trimethylchlorosilane, dimethylchlorosilane, methyltrichlorosilane, vinyltrichlorosilane, diphenyldichlorosilane, and triethylfluorosilane. Organohalosilanes such as silane, organosilicon esters such as trimethylacetoxysilane and dimethyldiacetoxysilane, organoalkoxysilanes such as trimethylmethoxysilane and dimethyldimethoxysilane,
Examples include organosilanols such as trimethylsilanol and diethylsilanediol, aminoalkylsilanes such as N-amiethyltrimethoxysilane, and organosilicon isocyanates such as trimethylsiliconisocyanate. The degree of modification by these silylating agents can be arbitrarily adjusted depending on the type, amount and reaction conditions of the silylating agent used.

The unsaturated monomer used in the method for saponifying a copolymer of a vinyl ester monomer and an unsaturated monomer having a silyl group in the molecule is vinyltrimethoxysilane. Many vinylsilane-based compounds such as vinylalkoxysilane and vinylmethyldimethoxysilane represented by vinyltriethoxysilane, and alkyl- or allyl-substituted vinylalkoxysilane represented by vinyltriisopropoxysilane; Further, polyalkylene glycol-modified vinyl silanes in which a part or all of these alkoxy groups are substituted with a polyalkylene glycol such as polyethylene glycol can be given. Furthermore, 3- (meth) acrylamino-propyltrimethoxysilane, 3
(Meth) acrylamide-alkylsilane represented by-(meth) acrylamide-propyltriethoxysilane and the like can also be preferably used.

On the other hand, a method of polymerizing a vinyl ester in the presence of a mercaptan having a silyl group or the like and then saponifying the silyl group to introduce a silyl group into the terminal includes an alkoxysilylalkyl such as 3- (trimethoxysilyl) -propylmercaptan. Mercaptan is preferably used.

The suitable range varies depending on the degree of modification of the modified polyvinyl alcohol-based resin of the present invention, that is, the content of the silyl group, the degree of saponification, etc., but it is important for the gas barrier property which is the object of the present invention. It becomes a factor. The content of the silyl group is usually 30 mol% or less, preferably 10 mol% or less, particularly preferably 5 mol% or less, as a monomer containing a silyl group, based on the vinyl alcohol unit in the polymer. Used. Although the lower limit is not particularly limited, the effect is particularly remarkably exhibited when it is 0.1 mol% or more.

The above-mentioned silylation ratio indicates the ratio of the introduced silyl group after the silylation to the amount of the hydroxyl group contained in the polyvinyl alcohol-based resin before the silylation.

These polyvinyl alcohol resins may of course be used alone, but as long as the object of the present invention is not impaired, they may be used as copolymers with other copolymerizable monomers or mixed with other monomers. It can be used in combination with other possible resin compounds. Examples of such a resin include polyacrylic acid or esters thereof, polyester resin, polyurethane resin, polyamide resin, epoxy resin, melamine resin, and others.

Polysaccharides are biopolymers synthesized in a biological system by polycondensation of various monosaccharides, and here also include those chemically modified based on them. Examples include cellulose and cellulose derivatives such as hydroxymethylcellulose, hydroxyethylcellulose and carboxymethylcellulose, amylose, amylopectin, pullulan, curdlan, xanthan, chitin, chitosan and the like.

The ethylene-vinyl alcohol copolymer (hereinafter referred to as EVOH) has a vinyl alcohol content of from 40 mol% to 80 mol%, more preferably from 45 mol% to 75 mol%. It means a certain EVOH. In addition, the melt index of EVOH (temperature 190
The value measured under the conditions of ° C and a load of 2160 g; hereinafter, referred to as MI) is not particularly limited, but is 0.1 to 50 g / 10 minutes. Further, the EVOH referred to in the present invention may be modified with a small amount of a comonomer as long as the object of the present invention is not hindered.

The above-mentioned modified EVOH is modified so as to be crosslinked, and preferably modified so as to be soluble in alcohol. In order to impart such properties, a silyl group is introduced into EVOH.

The introduction of the silyl group can be carried out by, for example, 3-isocyanatopropyltriethoxysilane, trimethylchlorosilane, dimethyldichlorosilane, methyltrichlorosilane, vinyltrichlorosilane, diphenyldichlorosilane, triethylfluoroorganohalosilane,
It is carried out by reacting a reactive silane compound, such as trimethylacetoxysilane, with a hydroxyl group of EVOH.

The introduction of the silyl group, ie, the silylation, needs to be performed at least so that EVOH becomes soluble in alcohol. Specifically, it is preferable that the silylation rate is 0.2 mol% or more. The upper limit of the silylation rate is not particularly limited from the viewpoint of alcohol solubility, but from the viewpoint of the arrangement of the inorganic layered compound in the present invention,
It is preferably at most 5 mol%, more preferably at most 2 mol%. The above silylation rate is the value of EVO before silylation.
It shows the ratio of the introduced silyl groups after silylation to the amount of hydroxyl groups contained in the H resin.

Modified EVOH into which the above silyl group has been introduced
Is dissolved in an alcohol-based solvent due to the presence of the introduced silyl group by heating and dissolving with an alcohol or a mixed solvent of alcohol / water. The modified EVOH dissolved in the solvent, on the other hand, cross-links by a part of the introduced silyl group reacting by a dealcoholization reaction and a dehydration reaction. In the above reaction, the presence of water is essential, and it is preferable to use a mixed solvent of alcohol / water.

The coating liquid is a liquid in which the above-mentioned inorganic layered compound and resin are dispersed or dissolved in a dispersion medium. From the viewpoint of the gas barrier properties of the obtained laminate, the dispersion medium is preferably a liquid that swells or cleaves the above-described inorganic layered compound.

The composition ratio of the inorganic layered compound to the resin in the coating liquid is not particularly limited, but generally, the weight ratio of the inorganic layered compound to the resin (inorganic layered compound / resin) is 1/100 to 100%. 100/1, furthermore 1/20 to 10/1
Is preferably within the range. The higher the weight ratio of the inorganic layered compound is, the more excellent the gas barrier property is, but in consideration of the bending resistance, the range of 1/20 to 2/1 is more preferable.

The concentration of the highly hydrogen-bonding resin and the inorganic layered compound in the coating solution is usually
It is preferably in the range of 0.1% by weight to 70% by weight, more preferably in the range of 1 to 15% by weight, and more preferably in the range of 4 to 10% by weight. Is more preferable.

Gas barrier layer 3 (coating liquid) in the present invention
In the case where the resin used is a high hydrogen bonding resin, a crosslinking agent for a hydrogen bonding group can be used for the purpose of improving the water resistance of the gas barrier layer 3.

Preferable examples of the crosslinking agent include coupling agents such as titanium coupling agents, silane coupling agents, melamine coupling agents, epoxy coupling agents, isocyanate coupling agents, and the like. Epoxy compounds, copper compounds, zirconium compounds, organometallic compounds and the like can be mentioned. From the viewpoint of improving water resistance, organometallic compounds, zirconium compounds, water-soluble epoxy compounds, silane coupling agents are more preferably used,
More preferably, it is an organic metal compound such as an organic titanium compound.

Specific examples of the above-mentioned zirconium compounds include, for example, halogenated zirconium such as zirconium oxychloride, zirconium hydroxychloride, zirconium tetrachloride and zirconium bromide; and mineral acids such as zirconium sulfate, basic zirconium sulfate and zirconium nitrate. Zirconium salts of organic acids such as zirconium formate, zirconium acetate, zirconium propionate, zirconium caprylate and zirconium stearate;
Examples include zirconium complex salts such as ammonium zirconium carbonate, sodium zirconium sulfate, ammonium zirconium acetate, sodium zirconium oxalate, sodium zirconium citrate, and zirconium ammonium citrate.

Specific examples of the water-soluble epoxy compound include sorbitol polyglycidyl ether, sorbitan polyglycidyl ether, glycidyl ether epoxy resin, heterocyclic epoxy resin, glycidylamine epoxy resin, and aliphatic epoxy resin. I can give it.

Examples of the silane coupling agent include amino silane coupling agents, vinyl or methacryloxy silane coupling agents, epoxy silane coupling agents, methyl silane coupling agents,
Chloro silane coupling agents and mercapto silane coupling agent systems are exemplified.

Preferred examples of the cross-linking agent for a hydrogen-bonding group include a reaction for forming a cross-linked structure by reacting with a plurality of functional groups of a high hydrogen-bonding resin, that is, an organic metal compound capable of a cross-linking reaction. For example, the above-mentioned organometallic compounds which react with a plurality of hydroxyl groups of polyvinyl alcohol and form a cross-linking by a coordination bond or an ionic bond between a metal atom of the organometallic compound and an oxygen atom of the hydroxyl group are preferable.

The above-mentioned organometallic compounds capable of undergoing a crosslinking reaction include:
Higher crosslinking reactivity and higher crosslinking efficiency than inorganic metal salts. However, if the cross-linking reactivity is too high, the cross-linking reaction proceeds in the coating solution and coating (coating) becomes impossible, but the cross-linking reactivity of the organometallic compound can be changed by appropriately changing the ligand. Easy to control. The organic metal compound is also superior to the inorganic metal salt in that it has the advantage that the reactivity is easily controlled. Among the organometallic compounds, an organometallic compound having a chelating ligand such as acetylacetonate has an appropriate crosslinking reactivity and is preferable as a crosslinking agent for a hydrogen bonding group.

Preferred examples of such an organometallic compound include an organic titanium compound, an organic zirconium compound, an organic aluminum compound, and an organic silicon compound.

Specific examples of the organic titanium compound include titanium orthoesters such as tetra-n-butyl titanate, tetraisopropyl titanate, butyl titanate dimer, tetra (2-ethylhexyl) titanate and tetramethyl titanate; titanium acetylacetonate;
Titanium chelates such as titanium tetraacetylacetonate, polytitanium acetylacetonate, titanium octylene glycolate, titanium lactate, titanium triethanolamine, titanium ethyl acetoacetate, and titanium acylates such as polyhydroxytitanium stearate. No.

Specific examples of the organic zirconium compound include zirconium normal propylate, zirconium normal butyrate, zirconium tetraacetylacetonate, zirconium monoacetylacetonate, zirconium bisacetylacetonate, zirconium acetylacetonate bisethylacetoacetate and the like. No.

Specific examples of the organoaluminum compound include aluminum acetylacetonate, aluminum organic acid chelate and the like. Examples of the organic silicon compound include a silicon compound having a ligand included in the compounds exemplified as the organic titanium compound or the organic zirconium compound.

Among these, a chelate compound is preferable in terms of stability in a coating solution. In terms of the stability of the coating solution, the stability is greatly improved by setting the coating solution to be acidic. The above acidic conditions include a pH of 5
Or less, more preferably pH 3 or less. There is no particular lower limit on the pH of the coating solution, but usually the pH is 0.1.
5 or more. As the addition method, it is preferable to dilute with an alcohol and add. By including the step of mixing the resin and the crosslinking agent, the gas barrier layer 3 in which the resin is crosslinked can be obtained.

The amount of the crosslinking agent to be added is not particularly limited, but the ratio K (K = CN / HN) of the number of moles of the crosslinking group (CN) of the crosslinking agent to the number of moles of the hydrogen bonding group (HN) of the resin is used. But,
It is preferable to use it in the range of 0.001 or more and 10 or less. The molar ratio K is more preferably in the range of 0.01 or more and 1 or less.

The method of blending or producing the resin composition comprising the above-mentioned inorganic layered compound and resin is not particularly limited.
From the viewpoint of uniformity or ease of operation at the time of blending, for example, after mixing a liquid obtained by dissolving a resin in a solvent and a dispersion obtained by previously swelling and cleaving an inorganic layered compound with a dispersion medium,
A method of removing a solvent and a dispersion medium (method 1), a method in which a dispersion liquid in which an inorganic layered compound is swollen and cleaved by a dispersion medium is mixed with a resin, the resin is dissolved in the dispersion medium, and then the dispersion medium is removed. Method (method 2), a method in which an inorganic layered compound is added to a liquid in which a resin is dissolved in a solvent, and the inorganic layered compound is swelled and cleaved using the solvent as a dispersion medium to form a dispersion, and the solvent is removed (method 3). Alternatively, a method of hot-kneading the resin and the inorganic layered compound (method 4) can be used. The former three methods are preferably used from the viewpoint that a large aspect ratio of the inorganic layered compound can be easily obtained. In the former three cases, it is preferable to perform treatment using a high-pressure dispersion device from the viewpoint of dispersibility of the inorganic layered compound.

As a high-pressure dispersion device, for example, Microflu
There is an ultra-high pressure homogenizer (trade name: Microfluidizer) manufactured by idics Corporation or a Nanomizer manufactured by Nanomizer, and a Menton-Gaulin type high-pressure dispersing apparatus such as a homogenizer manufactured by Izumi Food Machinery.

In the above three methods, after removing the solvent or the dispersion medium from the system and laminating, the resulting laminate is heat-aged at, for example, 110 ° C. or more and 220 ° C. or less. Is preferable because it can improve the water resistance (meaning of gas barrier properties after a water resistance environment test).

The aging time is not limited, but it is necessary that the laminated body reaches at least a set temperature. For example, in the case of a method using a hot medium such as a hot air dryer, the time is preferably from 1 second to 100 minutes. There is no particular limitation on the heat source, and various methods such as heat roll contact, heat medium contact (air, oil, etc.), infrared heating, and microwave heating can be applied.

The above aging treatment exhibits a particularly excellent effect in improving the water resistance when the resin is a high hydrogen bonding resin.

In the present invention, the high-pressure dispersion treatment is, as shown in FIG. 5, by causing a composition mixture obtained by mixing particles to be dispersed or a dispersion medium and the like to pass through a plurality of small tubes 11 at high speed and collide. Dispersing under special conditions such as high shear and high pressure.

In such a high-pressure dispersion treatment, the composition mixture is preferably passed through a thin tube 11 having a diameter of 1 μm to 1000 μm. When the composition mixture passes through the small tube 11, the maximum pressure condition is applied to the composition mixture. It is preferable that a pressure of 100 kgf / cm ² or more is applied.
/ Cm ² or more, more preferably 1000 kgf / cm ²
The above is particularly preferred. In addition, the composition mixture is a thin tube 11
When passing through the inside, the maximum arrival speed of the composition mixture is 1
00 m / s or more, and the heat transfer rate is 1
It is preferably at least 00 kcal / hr.

The principle of the high-pressure treatment in the high-pressure dispersion treatment apparatus used for the high-pressure dispersion treatment will be schematically described.
The composition mixture is sucked into the feeder tube 13 having a larger diameter than the thin tube 11 by the pump 12 and taken in. Subsequently, a high pressure is applied to the composition mixture in the feeder tube 13 by the pump 12. At this time,
Check valve provided on feeder tube 13 (not shown)
As a result, the composition mixture in the feeder tube 13 is
Extruded toward one. Therefore, the composition mixture is in a high-pressure and high-speed state in the thin tube 11,
Each of the inorganic layered compound particles of the composition mixture collides with each other and the inner wall of the thin tube 11, and the diameter and thickness, particularly the thickness, of each of the inorganic layered compound particles are finely divided and more uniformly dispersed. Then, it is taken out of the discharge pipe 14 to the outside.

For example, in the case where the flow velocity at the point where the maximum velocity is instantaneously reached with respect to the composition mixture which is the sample to be processed in the portion of the thin tube 11 is 300 m / s, the volume is 1 × 1
When passing through a cube of 0 ^-3 m ³ at 1 / (3 × 10 ⁵ ) sec and the temperature of the composition mixture rises by 35 ° C., energy is transferred to the composition mixture by pressure loss. The heat transfer rate is such that the specific gravity of the composition mixture is 1 g / cm ^{3 and the} specific heat 1 ca.
At 1 / g ° C., it is 3.8 × 10 ⁴ kcal / hr.

In the oxygen-absorbing packaging material according to the present invention, corona treatment, flame plasma treatment, ozone treatment, electron beam irradiation treatment, anchor treatment are used to improve the adhesion between the gas barrier layer 3 and the substrate. May be performed between each layer. Although any of these processes is not particularly limited, for example, an anchor process is suitably used.

The anchor treatment is a treatment for forming the anchor layer 2 between the base material 1 and the gas barrier layer 3 as shown in FIG. The material of the anchor layer 2 is not particularly limited, but preferably contains an isocyanate compound and an active hydrogen compound.

As the isocyanate compound contained in the anchor layer 2, tolylene diisocyanate (TD)
I), 4,4'-diphenylmethane diisocyanate (MD
I), xylylene diisocyanate (XDI), hexamethylene diisocyanate (HDI), 4,4'-methylenebiscyclohexyl isocyanate (H12MDI), isophorone diisocyanate (IPDI) and the like.

The active hydrogen compound has only to have a functional group that binds to an isocyanate compound. Examples thereof include ethylene glycol, diethylene glycol, dipropylene glycol, 1,4-butanediol, and the like.
1,6-hexanediol, neopentyl glycol, low molecular weight polyols such as trimethylolpropane, polyethylene glycol, polyoxypropylene glycol,
Ethylene oxide / propylene oxide copolymers, polyether polyols such as polytetramethylene ether glycol, poly-β-methyl-δ-valerolactone,
Polycaprolactone, polyester polyols such as polyester from diol / dibasic acid, and the like.

Among the active hydrogen compounds, low molecular weight polyols are particularly preferable, and diols in the low molecular weight polyols are more preferable. Here, diols include ethylene glycol, diethylene glycol, dipropylene glycol, 1,4-butanediol, 1,6-hexanediol, neopentyl glycol, and the like, and dibasic acids such as adipic acid, azelaic acid, sebacic acid, and isophthalic acid And terephthalic acid. Other polyols include active hydrogen compounds such as castor oil, liquid polybutadiene, epoxy resin, polycarbonate diol, acrylic polyol, and neoprene.

The mixing ratio between the isocyanate compound and the active hydrogen compound is not particularly limited, but the amount to be added may be determined in consideration of the equivalence relationship between the isocyanate group and the active hydrogen group, for example, —OH, —NH, and —COOH. preferable. For example, the ratio R (R = A) between the number of moles of isocyanate groups (AN) and the number of moles of active hydrogen groups (BN) of the active hydrogen compound
N / BN) is preferably 0.001 or more from the viewpoint of adhesive strength, and is preferably 10 or less from the viewpoint of tackiness and blocking. The number of moles of the isocyanate group and the active hydrogen group can be determined by 1H-NMR and 13C-NMR.

The method for laminating the anchor layer 2 on the substrate 1 is not particularly limited, but a coating method using an anchor coating agent solution obtained by dissolving an anchor coating agent containing an isocyanate compound and an active hydrogen compound in a solvent is preferable. . Specific examples of the coating method include a direct gravure method, a reverse gravure method, a microgravure method, a roll coating method such as a two roll beat coating method and a bottom feed three reverse coating method, and a doctor knife method and a die coating method. Examples include a dip coating method, a bar coating method, and a coating method combining these methods.

The solvent component in the anchor coating agent solution is mainly an organic solvent, and includes alcohols, aliphatic hydrocarbons, alicyclic hydrocarbons, aromatic hydrocarbons, esters, ketones, ethers, and the like. Halogenated hydrocarbons and mixed solvents thereof are exemplified.

The coating thickness of the anchor coating agent solution applied to the substrate 1 in the form of a film is not particularly limited, but is preferably set so that the dry thickness is 0.01 μm to 5 μm. The larger the coating thickness, the better the heat sealing strength, but the lower the gelboflex resistance. Therefore, the coating thickness is more preferably from 0.03 μm to 2.0 μm.
m, more preferably 0.05 μm to 1.0 μm
It is.

With the anchor layer 2, it is possible to obtain better adhesion than simply laminating the gas barrier layer 3 on the substrate 1. In order to further improve the adhesion, the gas barrier layer 3 may contain a surfactant.

The surfactant is not particularly limited as long as it can improve the adhesiveness between the anchor layer 2 and the gas barrier layer 3. Examples of the surfactant include anionic surfactants, cationic surfactants, and the like. Zwitterionic and non-ionic surfactants are included.

Examples of the anionic surfactant include a carboxylic acid type such as an aliphatic monocarboxylate, N-acyloylglutamate, an alkylbenzene sulfonate, a naphthalene sulfonate-formaldehyde condensate, and a dialkyl sulfosuccinate. Hydrocarbon-based anionic interfaces such as sulfonic acid type, alkyl sulfate type, sulfate type such as alkyl sulfate polyoxyethylene salt, phosphate type such as alkyl phosphate salt, borate type such as alkyl borate salt Activators, fluorinated anionic surfactants such as sodium perfluorodecanoate and sodium perfluorooctylsulfonate; silicone-based anionics having anionic groups such as polymers having polydimethylsiloxane groups and metal carboxylate Surfactants.

Examples of the cationic surfactant include an amine salt type such as an alkylamine salt and a quaternary ammonium salt type such as an alkyltrimethylammonium salt, a dialkyldimethylammonium salt and an alkyldimethylbenzylammonium salt.

Examples of the amphoteric surfactant include carboxybetaine type such as N, N-dimethyl-N-alkylaminoacetic acid betaine and glycine such as 1-alkyl-1-hydroxyethyl-1-carboxymethylimidazolinium betaine. Type.

Examples of the nonionic surfactant include ester types such as glycerin fatty acid ester, sorbitan fatty acid ester, and sucrose fatty acid ester, condensation polymers of polydimethylsiloxane groups and alkylene oxide adducts, and polysiloxane-polyoxyalkylene copolymers. Polymer, ether type such as polyoxyethylene alkylphenyl ether, polyoxyethylene alkyl ether, polyoxyethylene polyoxypropylene block polymer, etc., ester ether type such as polyethylene glycol fatty acid ester, polyoxyethylene sorbitan fatty acid ester, aliphatic alkanolamide Alkanolamide type, such as
Fluorine type such as diglycerin ester of perfluorodecanoic acid and perfluoroalkylalkylene oxide compound are exemplified.

Among the above surfactants, in particular, those having 6 carbon atoms
An alkali metal salt of a carboxylic acid having an alkyl chain of not more than 24 or less, an ether type nonionic surfactant such as polydimethylsiloxane-polyoxyethylene copolymer (silicone nonionic surfactant), Fluorinated nonionic surfactants such as alkyl ethylene oxide compounds (fluorinated nonionic surfactants)
Is preferred.

In the case where a coating liquid is used when forming the gas barrier layer 3, for example, the amount of the surfactant is preferably 0.001 to 5% by weight in the coating liquid from the viewpoint of the effect. 0.003 to 0.5% by weight is more preferable,
Particularly preferred is 0.5 to 0.1% by weight.

In the oxygen-absorbing packaging material according to the present invention,
The base resin for laminating the gas barrier layer 3 and the anchor layer 2 described above is not particularly limited. As the base resin, specifically, papers such as kraft paper, high-quality paper, imitation paper, glassine paper, parchment paper, synthetic paper and various cardboard, polyethylene (low density, high density),
Ethylene-propylene copolymer, ethylene-butene copolymer, ethylene-hexene copolymer, ethylene-octene copolymer, polypropylene, ethylene-vinyl acetate copolymer, ethylene-methyl methacrylate copolymer, ionomer resin, etc. Polyolefin resins, polyester resins such as polyethylene terephthalate, polybutylene terephthalate, and polyethylene naphthalate, nylon-6, nylon-6,6, methacrylenediamine-adipic acid condensation polymer, amide resins such as polymethylmethacrylimide, Acrylic resin such as polymethyl methacrylate, polystyrene, styrene-acrylonitrile copolymer, styrene-acrylonitrile-butadiene copolymer, styrene-acrylonitrile such as polyacrylonitrile Fat, cellulose triacetate, hydrophobic cellulose-based resin such as di-cellulose acetate, polyvinyl chloride, polyvinylidene chloride, polyvinylidene fluoride, halogen-containing resins such as Teflon, polyvinyl alcohol,
Engineering of high hydrogen bonding resins such as ethylene-vinyl alcohol copolymers and cellulose derivatives, polycarbonate resins, polysulfone resins, polyethersulfone resins, polyetheretherketone resins, polyphenylene oxide resins, polymethylene oxide resins, liquid crystal resins, etc. Examples include a plastic resin, a resin having a metal or metal oxide layer such as aluminum, silica, and alumina.

Among the above-mentioned base resins, in particular, biaxially-stretched polypropylene (OPP), biaxially-stretched polyethylene terephthalate (OPET), biaxially-stretched nylon (ONy), and polychloride called K coat Vinylidene-coated OPP, OPET, ONy, and polyethylene terephthalate, polypropylene, nylon and OPP (AS-OP) for strong antistatic use having the above metal or metal oxide layer, and having the above metal or metal oxide layer OPP, OPET, ONy and the like are particularly preferably used.

The method of laminating the gas barrier layer 3 on the substrate 1 on which the anchor layer 2 is laminated is not particularly limited, but a coating solution of a resin composition is applied to the surface of the substrate 1, dried and heat-treated. A method of coating, a method of laminating a resin composition film on the anchor layer 2 later, and the like are preferable, and a method of performing the above-described coating is particularly preferable. In addition, at the time of coating, the resin contained in the coating liquid is preferably the high hydrogen bonding resin from the viewpoint of dispersibility.

Examples of the coating method include a roll coating method such as a direct gravure method, a reverse gravure method, a microgravure method, a two roll beat coating method, a bottom feed three reverse coating method, a doctor knife method, a die coating method, and a dip coating method. Method, a spin coating method, a bar coating method, and a coating method combining these methods.

The film thickness of the gas barrier layer 3 is 10
μm or less is preferable, and 1 μm or less is more preferable.
Particularly preferred is a range of 1 to 1 μm. In particular, when transparency of the oxygen-absorbing packaging material is required, the thickness is desirably 1 μm or less. In order to obtain sufficient gas barrier properties, the thickness of the gas barrier layer 3 should be 1 nm.
It is preferable that it is above.

In the oxygen-absorbing packaging material according to the present invention, as shown in FIG.
A sealant layer 4 for improving heat sealability may be laminated. The resin used for the sealant layer 4 is
Although not particularly limited, polyethylene (low-density, high-density), ethylene-propylene copolymer, ethylene-butene copolymer, ethylene-hexene copolymer, due to the problem of desorption such as heat seal strength, food aroma, and resin odor. , Ethylene-4-methyl-1-pentene copolymer, ethylene-octene copolymer, polypropylene, ethylene-vinyl acetate copolymer, ethylene-methyl methacrylate copolymer, ethylene-methyl acrylate copolymer, ethylene- Polyolefin resins such as acrylic acid copolymers, ionomer resins and ethylene-vinyl alcohol copolymers; polyacrylonitrile resins (PAN); polyester resins; and the like are preferably used.

In the oxygen-absorbing packaging material according to the present invention, it is preferable to use the sealant layer 4 having high impact strength, particularly when the sealing property of the contents is required. Examples of such a resin include polyethylene and ethylene-ethylene obtained using a metallocene catalyst or a late transition metal complex catalyst.
Polyolefin resins such as α-olefin copolymers are preferred. Such a sealant layer 4 has a density of 0.92.
It is preferably 0 g / cm ³ or less.

As a method for laminating the sealant layer 4,
Although not particularly limited, for example, a method in which the resin used for the sealant layer 4 is dissolved in a solvent and coated on the gas barrier layer 3 made of an inorganic layered compound and a resin, and the sealant layer 4 is extruded and laminated on the gas barrier layer 3 Preferred examples include a method and a method of dry laminating the sealant layer 4 on the gas barrier layer 3. Further, the interface between the sealant layer 4 and the gas barrier layer 3 may be subjected to a corona treatment, a flame plasma treatment, an ozone treatment, an electron beam treatment, or a treatment such as an anchor coating agent.

Further, as described above, the oxygen-absorbing packaging material according to the present invention may have a layer made of a metal or metal oxide such as aluminum, silica, and alumina. Examples of a method for forming the metal or metal oxide layer include a sol-gel method and a vapor deposition method, and are not particularly limited, but a vapor deposition method is preferable.

The thickness of the metal or metal oxide layer is generally in the range of 1 nm to 1000 nm, preferably in the range of 10 nm to 200 nm. The layer made of the metal or the metal oxide may be provided between any of the layers of the laminate. Thereby, the gas barrier property of the oxygen-absorbing packaging material according to the present invention can be improved, and, for example, the content can be shielded from light, so that the deterioration of the content can be further suppressed.

Conventionally, as one of the constitutions for further improving the gas barrier property of the packaging material, usually 7 μm to 20 μm is used.
Aluminum foil having a film thickness in the range of about m is often laminated. However, when an aluminum foil is used for the packaging material, a large amount of residue (ingot) is generated when the packaging material is used and then incinerated, and the resin layer of the packaging material body and the aluminum foil are hardly separated. As a result, there arises a problem that the recyclability of the packaging material is reduced, and it is difficult to reuse the container.

However, the oxygen-absorbing packaging material according to the present invention has the gas barrier layer 3 made of a resin composition having an inorganic layered compound.
It is possible to exhibit a very excellent gas barrier property even by using only this. Therefore, in the oxygen-absorbing packaging material, it is not necessary to adopt the above-described configuration in which the aluminum foil is laminated in order to further improve the gas barrier property, and the metal or metal oxide having a smaller thickness is deposited. Stacking the layers is sufficient.

The thickness of the above-mentioned vapor deposition layer is usually from 1 nm to 1000
nm, which is smaller than that of the above aluminum foil. Therefore, the amount of metal or metal oxide used per predetermined packaging material can be reduced, and excellent effects such as improvement in recyclability and reduction in the amount of residue (ingot) at the time of incineration can be obtained. .

Further, as long as the effect of the oxygen-absorbing packaging material according to the present invention is not impaired, at least one of the substrate 1, the anchor layer 2, the gas barrier layer 3 and the sealant layer 4 may be provided with an ultraviolet absorber, a crosslinking agent, Various additives such as coloring agents and antioxidants may be mixed.

The oxygen-absorbing wrapping material according to the present invention has a higher oxygen-absorbing property than a laminate having the above-described base material 1 provided with the gas barrier layer 3, preferably the anchor layer 2 and the sealant layer 4. Is given. Although there is no particular limitation on the method of imparting oxygen absorbency to the laminate, a method of laminating an oxygen absorbing layer and a method of encapsulating a deoxidizer as at least one of the layers of the oxygen absorbing packaging material. Particularly preferred.

The former (lamination of an oxygen-absorbing layer) is a method in which a material obtained by kneading an oxygen-absorbing material such as iron powder into a thermoplastic resin is molded into a layer and laminated, thereby providing the present invention. Oxygen absorbing properties can be imparted to the oxygen absorbing packaging material. In addition, it is preferable that the oxygen absorbing layer is disposed closer to the contents than the gas barrier layer 3.

On the other hand, in the latter case (encapsulation of a deoxidizer),
The method of encapsulation is not particularly limited. In addition, the oxygen absorber used is enclosed on the inner surface of the oxygen-absorbing packaging material, that is, when packaging the content using the oxygen-absorbing packaging material, not on the outside air but on the surface in contact with the content. Is preferred.

[0141] As shown in FIG.
7 is provided with a gas barrier layer 3, preferably an anchor layer 2, and more preferably a sealant layer 4 as shown in FIG. 7. At this time, the gas barrier layer It is preferable to be on the 3rd side or the sealant layer 4 side. This is because the purpose of the oxygen-absorbing packaging material is to block oxygen from the content, and it is preferable to arrange a layer exhibiting gas barrier properties for blocking oxygen from the outside air at a position closest to the content. is there.

The oxygen scavenger is not particularly limited as long as it exhibits oxygen absorbability for absorbing oxygen.
For example, a metal or inorganic oxygen absorber such as powdered iron or an organic oxygen absorber can be mentioned as the active ingredient. Only one oxygen absorber as an active ingredient may be used as the oxygen absorber, or a plurality of oxygen absorbers may be used as the oxygen absorber. Since the oxygen-absorbing packaging material according to the present invention is suitable for packaging foods and medicines, it is particularly preferable that the oxygen-absorbing agent has no oral toxicity or carcinogenicity, and among them, iron is preferred.

The oxygen scavenger is not particularly limited as long as it has a property of absorbing oxygen (oxygen absorptivity), and may be an inorganic oxide such as one containing powdered iron (iron powder) as a main component. -Based oxygen absorbers (for example, manufactured by Taisei Kaken Co., Ltd .: trade name Kebron, manufactured by Diamond Chemifa Co., Ltd .: trade name ORC, etc.)
And an organic oxygen scavenger such as one containing L-ascorbic acid as a main component (for example, trade name: Tamoto, manufactured by Toyo Pulp Co., Ltd.). Further, a combination of inorganic and organic oxygen scavengers may be used. In addition, it may have a property as a gas replacement agent that can be replaced with carbon dioxide after absorbing oxygen (for example, manufactured by Mitsubishi Gas Chemical Co., Ltd .: trade name: Ageless, Toa Gosei Chemical Industry Co., Ltd.) ): Trade name Vitalon, Toppan Printing Co., Ltd .: trade name freshness retaining agent C, etc.).

Since the oxygen-absorbing packaging material according to the present invention is suitable for packaging foods and pharmaceuticals, it is particularly preferable that the oxygen-absorbing agent has no oral toxicity or carcinogenicity. Among them, the above-mentioned iron powder and L-ascorbic acid are preferable.

The oxygen scavenger is sealed on the inner surface side (side in contact with the contents) of the oxygen-absorbing packaging material, but the method of sealing is not particularly limited. If is a small bag, a method using an automatic charging machine (eg, AG-1ES automatic charging machine manufactured by Mitsubishi Gas Chemical Co., Ltd.) that can be sealed in conjunction with the automatic packaging machine can be adopted. If the oxygen scavenger is in the form of a seal, a method in which the oxygen scavenger is attached to the inner surface of the oxygen-absorbing packaging material for automatic packaging can be adopted. It is sufficient that the oxygen scavenger is in contact with at least the inner surface when viewed from the gas barrier layer 3.

The above oxygen scavenger can maintain its oxygen absorbing property (deoxidizing property) as the oxygen permeability of the oxygen absorbing packaging material (laminate) is lower. That is, when the contents are wrapped with the oxygen-absorbing wrapping material, the inside is usually replaced with nitrogen or degassed (or vacuum wrapped).
To remove oxygen as much as possible. Therefore, the oxygen scavenger has a slight residual oxygen inside,
It absorbs oxygen that penetrates through the packaging material from outside air.

Here, since the amount of oxygen remaining inside is very small, it is the oxygen that enters from outside air that significantly reduces the oxygen absorbability. In contrast, the oxygen-absorbing packaging material according to the present invention has an oxygen permeability of 1 mL /
m ² · day · atm or less.
1 mL / m ² · day · atm or less, more preferably 0.0
It is less than 5 mL / m ² · day · atm. Therefore, it is possible to maintain a state in which almost no oxygen permeates the oxygen-absorbing packaging material from the outside air and penetrates into the inside, so that the oxygen absorbing property of the oxygen scavenger can be maintained for an extremely long time. Become.

The shape of the oxygen-absorbing wrapping material according to the present invention is not particularly limited as long as the above-mentioned laminate is processed into a shape that does not form a space or a hole through which outside air can enter. As the shape of the packaging, specifically,
For example, vertical pillow packaging bag, horizontal pillow packaging bag, gusset packaging bag, three-side seal packaging bag, four-side seal packaging bag, envelope pasting bag, stick packaging bag, rocket packaging, twist packaging, drawing packaging, PTP (press-through) Package) Packaging, strip packaging, blister packaging, standing pouch, tray (especially with top seal),
Cups (especially those with a top seal), vacuum / pressure molded containers and lids, injection or press molded containers and lids, squeeze bottles, bag-in-boxes, brick-shaped containers, gable tops, composite containers ,
Lami tubes, plastic can containers, square bottom bag containers, paper carton containers, bottles and the like can be mentioned.

Among the above packaging shapes, a vertical pillow packaging bag, a horizontal pillow packaging bag, a gusset packaging bag, a three-side seal packaging bag, a four-side seal bag, a pair of a vacuum / pressure-formed container and a lid member,
Packaging in the form of a container or a wrapper such as a pair of an injection or press molded container and a lid, a squeeze bottle, a standing pouch, a bag-in-box, a paper carton container, and a bottle is more preferable.

As described above, the oxygen-absorbing packaging material according to the present invention is suitably used for packaging contents that are deteriorated by contact with oxygen. Such contents are not particularly limited, but include foods, pharmaceuticals, and electronic materials. Among them, many foods are significantly deteriorated by oxygen, and thus the oxygen-absorbing packaging material of the present invention can be suitably used as a food packaging material.

The shape of the food packaging material is not particularly limited, and the food to be packaged is not particularly limited. However, for example, fresh foods such as prepared foods, processed livestock products, and processed marine products are oxidized by contact with oxygen and are significantly deteriorated, so that they are particularly suitable for use in packaging the food packaging material.

[0152] Also, many confectionery products are liable to be deteriorated by contact with oxygen, and thus can be suitably used for confectionery packaging. Furthermore, many snacks use, for example, edible oil, but since this edible oil is easily oxidized by contact with oxygen, the oxygen-absorbing packaging material according to the present invention is also suitable for snacks packaging. Can be used. As described above, freshness is emphasized in the food and it is necessary to avoid deterioration as much as possible. Therefore, the oxygen-absorbing packaging material according to the present invention can be used very suitably as a food packaging material.

In addition, many quasi-drugs, including pharmaceuticals and toiletries, are deteriorated by contact with oxygen. Therefore, the oxygen-absorbing packaging material according to the present invention is suitably used as a pharmaceutical packaging material. Can be used.

As described above, the oxygen-absorbing packaging material according to the present invention is formed by using a laminate having a gas barrier layer, and has an oxygen-absorbing property on the inner surface side of the oxygen-absorbing packaging material. Therefore, since the oxygen absorption provided to the packaging material is maintained for a long time by the gas barrier property, the combined use of the excellent gas barrier property and the long-term oxygen absorption property makes it possible to simply compare the packaging material having the gas barrier property with the gas barrier property. Thus, the deterioration of the contents due to oxygen can be suppressed very effectively.

Further, a food packaging material according to the present invention is manufactured using the oxygen absorbing packaging material. Therefore, compared to conventional food packaging materials, it is possible to more effectively suppress the deterioration of the contents due to oxygen, and it is not particularly limited to foods only, and is used in any packaging that takes such a form. It is possible.

[0156]

The present invention will be described in detail below with reference to examples and comparative examples, but the present invention is not limited to these examples. In the examples and comparative examples, various physical properties of the laminate used for the oxygen-absorbing packaging material (food packaging material) were measured as follows.

[Thickness Measurement] The thickness of 0.5 μm or more was measured with a commercially available digital thickness gauge (contact type thickness gauge, trade name: ultra-high precision decimicro head MH-15M, manufactured by Nippon Kogaku Co., Ltd.). On the other hand, when the thickness is less than 0.5 μm, the thickness of the actual coating film is determined by a gravimetric analysis method (the measured weight value of a film having a certain area is divided by the area and further divided by the specific gravity of the resin composition) or the IR method. A calibration curve of the thickness and the IR absorption was prepared, and determined by the calibration curve. Further, in the case of measuring the thickness of the coating film of the resin composition of the present invention, for example, the elemental analysis method (the ratio of the specific inorganic element analysis value of the laminate (derived from the barrier layer) to the specific element fraction of the inorganic layered compound alone) From the method of the present invention for determining the ratio between the barrier layer and the substrate.

[Measurement of Particle Size] Using a laser diffraction / scattering type particle size distribution analyzer (LA910, manufactured by HORIBA, Ltd.), the volume-based median of particles considered to be inorganic layered compounds present in the resin matrix of the medium. The diameter was measured as a particle diameter L. The undiluted dispersion was measured at a light wavelength of 50 μm in a paste cell, and the diluent of the dispersion was measured at a light wavelength of 4 mm by a flow cell method.

[Aspect Ratio Calculation] X-ray diffractometer (XD
-5A (manufactured by Shimadzu Corporation), the diffraction measurement of the inorganic layered compound alone and the resin composition by the powder method was performed. Thereby, the unit thickness a of the inorganic layered compound was obtained, and further, from the diffraction measurement of the resin composition, it was confirmed that there was a portion where the interplanar spacing d of the inorganic layered compound was widened. Using the particle diameter L obtained by the above-described method, the aspect ratio Z is calculated as follows: Z = L / a
It calculated by the formula of.

[Oxygen Permeability Measurement] Based on JIS K7126, an oxygen permeability measuring device (OX-TRANML: M
OCON) at 23 ° C. and 50% RH.

[Example] Dispersing pot [Product name: Despa MH-
L, manufactured by Asada Tekko Co., Ltd.], 1410 g of ion-exchanged water (specific electric conductivity 0.7 μS / cm or less) was added, and polyvinyl alcohol [PVA117H; manufactured by Kuraray Co., Ltd.
Saponification degree: 99.6%, polymerization degree: 1700] and 50 g under low-speed stirring (1500 rpm, peripheral speed: 4.10 m / min).
Heat to 5 ° C., stir for 1 hour, and dissolve.

Next, the temperature was lowered to 60 ° C. while stirring, and 15 g of 1-butanol was added dropwise to adjust the final 1-butanol fraction to 1% by weight. Then, 25 g of natural montmorillonite (Kunipia F; manufactured by Kunimine Industry Co., Ltd.) was added as powder, and after confirming that montmorillonite was substantially precipitated in the liquid, high-speed stirring (31)
(00 rpm, peripheral speed: 8.47 m / min) for 90 minutes to obtain a resin composition mixed solution (A) having a total solid content concentration of 5 wt%. (The particle size of the cleaved natural montmorillonite (Kunipia F) is 560 nm, the a value obtained from powder X-ray diffraction is 1.2156 nm, and the aspect ratio (Z) is 450 or more.) Further, 92 g of 1-butanol , 277 g of isopropyl alcohol, and a nonionic surfactant SH374
6 [Polyoxyethylene-methylpolysiloxane copolymer, manufactured by Dow Corning Toray Co., Ltd.] is added to obtain 0.18 g of the liquid.

The liquid (B) was added to the liquid (A) under low-speed stirring (15
00 rpm, peripheral speed 4.10 m / min), and further added titanium acetylacetonate [TC1
00, manufactured by Matsumoto Pharmaceutical Co., Ltd.] under low-speed stirring (1500
(3.3 rpm) at a peripheral speed of 4.10 m / min).

A biaxially oriented polypropylene (OPP) film having a thickness of 20 μm (Pyrene P2102; manufactured by Toyobo Co., Ltd.) was treated with a surface corona to form a substrate (substrate film). Coating agent [Adcoat AD335 / CAT10 = 15/1
(Weight ratio: manufactured by Toyo Morton Co., Ltd.)] (test coater; manufactured by Yasui Seiki: microgravure coating method, coating speed 3 m / min, drying temperature 80 ° C.). The dry thickness of the anchor coat layer was 0.15 μm.

Further, as TOP coating liquid, coating liquid 1
By gravure coating (test coater; manufactured by Yasui Seiki Co., Ltd .: microgravure coating method, coating speed 3 m / min, drying temperature 100)
° C) to obtain a coating film (laminate) having a gas barrier layer based on the coating liquid 1 formed on the anchor coat layer. The dry thickness of the gas barrier layer was 0.5 μm.

Next, a linear low-density polyethylene (LLDPE) [KF101, Seki-Fill (LODPE), whose surface was corona-treated, using a urethane-based adhesive (Eunoflex J3: manufactured by Sanyo Chemical Industries) for the gas barrier layer of the coating film stock)
(Thickness: 40 μm) as an outer layer (sealant layer). At this time, an oxygen scavenger containing powdered iron as a main component was sealed between the coating film and the sealant layer. Thus, the oxygen-absorbing packaging material according to the present invention was obtained.

This oxygen-absorbing packaging material was processed into a four-sided seal packaging bag, a vacuum / pressure-formed container and a lid material, and used as a food packaging material. Among these food packaging materials, “Tororo kelp” is contained as a content in a four-side seal packaging bag, and “Miso” is contained as a content in a vacuum / pressure molded container. The detection agent Ageless Eye (trade name, manufactured by Mitsubishi Gas Chemical Co., Ltd.) was enclosed and sealed.

Each food packaging material containing these foods as contents was allowed to stand for 30 days at 23 ° C., and the color change of the ageless eye and the hue change of the content food were visually confirmed. did. Further, the oxygen permeability of the laminate used for the food packaging material (oxygen absorbing packaging material) was measured. Table 1 shows the results.

Comparative Example A comparative oxygen absorbing packaging material was obtained in the same manner as in the above example, except that a polyvinylidene chloride resin layer was formed instead of the gas barrier layer. This oxygen-absorbing packaging material was processed into a four-sided sealing packaging bag, and a vacuum / pressure-formed container and lid material in the same manner as in the example to form a food packaging material. Similarly, “Tororo kelp” and “Miso” were stored, and the inside was replaced with nitrogen and sealed.

Each food packaging material containing these foods as contents was allowed to stand under the same conditions as in the example,
The color change of the ageless eye and the hue change of the content food were visually confirmed. It should be noted that the ageless eye shows a pink color when the oxygen concentration is almost 0%, and turns blue when the oxygen concentration is 0.5% or more. It is intended as a guide for evaluation. Moreover, the oxygen permeability of the laminated body used for the food packaging material (oxygen absorbing packaging material) was measured in the same manner as in the examples. Table 1 shows the results.

[0171]

[Table 1]

In Table 1, 場合 indicates that there is almost no color change, △ indicates that a slight color change has occurred, and X indicates that a significant color change has occurred.

As can be seen from the results shown in Table 1, the oxygen-absorbing packaging material and the food packaging material according to the present invention have a higher content than the comparative oxygen-absorbing packaging material and the food packaging material of the comparative example. It is understood that deterioration of the product due to oxygen can be significantly suppressed.

[0174]

As described above, the oxygen-absorbing packaging material according to the first aspect of the present invention has an oxygen-absorbing property for storing and packaging the contents and absorbing oxygen in contact with the contents. The oxygen-absorbing packaging material includes a laminate having a gas barrier layer made of a resin composition having an inorganic layered compound, and the surface of the laminate in contact with the contents is provided with the oxygen-absorbing property. Configuration.

As described above, the oxygen-absorbing packaging material according to claim 2 of the present invention has the following features.
The above-described oxygen absorbing property is provided by enclosing an oxygen scavenger between at least the gas barrier layer and the surface of the laminate in contact with the contents.

As described above, the oxygen-absorbing packaging material according to the third aspect of the present invention may be configured such that the oxygen-absorbing packaging material is a vertical pillow packaging bag or a horizontal pillow packaging. Bags, gusset packaging bags, three-side seal packaging bags, four-side seal packaging bags, pairs of vacuum / pressure molded containers and lids, pairs of injection or press molded containers and lids, squeeze bottles,
This is a configuration processed into at least one type of packaging shape selected from a standing pouch, a bag-in-box, a paper carton container, and a bottle.

[0177] As described above, in the oxygen-absorbing packaging material according to the fourth aspect of the present invention, in addition to the structure of the first, second or third aspect, the laminate further includes a metal or metal oxide layer. This is a configuration having at least one layer.

[0178] According to the oxygen absorbing packaging material of the fifth aspect of the present invention, as described above, in addition to the constitution of any one of the first to fourth aspects, the laminate further comprises a polyolefin resin layer. This is a configuration having at least one layer.

As described above, the oxygen-absorbing wrapping material according to claim 6 of the present invention further comprises a biaxially stretched film in which the laminate is further provided in addition to the constitution according to any one of claims 1 to 5. This is a configuration having at least one layer.

As described above, the oxygen-absorbing packaging material according to the seventh aspect of the present invention has an oxygen permeability of 1 mL / m ² ··· in addition to the configuration according to any one of the first to sixth aspects. da
y ・ Atm or less.

The oxygen-absorbing packaging material according to the eighth aspect of the present invention is, as described above, in addition to the constitution according to any one of the first to seventh aspects, wherein the inorganic layered compound is added to a dispersion medium. It is a configuration that swells and cleaves.

The oxygen-absorbing packaging material according to the ninth aspect of the present invention provides the oxygen-absorbing packaging material according to any one of the first to seventh aspects, wherein the gas barrier layer comprises an inorganic layered compound. This is a configuration obtained by subjecting a mixed solution of the resin composition having a high pressure to a dispersion treatment.

The oxygen-absorbing packaging material according to the tenth aspect of the present invention is, as described above, in addition to the configuration according to the ninth aspect, wherein the high-pressure dispersion treatment is performed under a pressure condition of 100 kgf / cm ² or more. Configuration.

As described above, the oxygen-absorbing packaging material according to the eleventh aspect of the present invention has an inorganic layered compound having an aspect ratio of 50, in addition to the configuration according to any one of the first to tenth aspects. The configuration is within the range of ０００5000.

As described above, the oxygen-absorbing packaging material according to the twelfth aspect of the present invention has, in addition to the constitution according to any one of the first to eleventh aspects, an aspect ratio of the inorganic layered compound of 200. The configuration is within the range of 範 囲 3000.

As described above, the oxygen-absorbing packaging material according to the thirteenth aspect of the present invention is characterized in that, in addition to the constitution according to any one of the first to twelfth aspects, the resin composition has a high hydrogen bonding property. The composition contains a resin and the weight ratio of the inorganic layered compound to the high hydrogen bonding resin is in the range of (1/100) to (100/1).

As described above, the oxygen-absorbing packaging material according to the fourteenth aspect of the present invention, in addition to the constitution according to the thirteenth aspect, is characterized in that the high hydrogen-bonding resin comprises a hydrogen-bonding group or an ionic group per unit weight of the resin. Mol% of the functional group is 30% or more, 50%
The configuration is as follows.

As described above, the oxygen-absorbing packaging material according to the fifteenth aspect of the present invention may further comprise, in addition to the constitution according to the eleventh or twelfth aspect, the high-hydrogen-bonding resin comprising polyvinyl alcohol and a modified product thereof. The composition is a polysaccharide or an ethylene-vinyl alcohol copolymer and a modified product thereof.

[0189] By having each of the above structures, the oxygen-absorbing wrapping material of the present invention can maintain the oxygen-absorbing property imparted to the wrapping material for a long time. As a result, the combined use of the excellent gas barrier properties and the long-term oxygen absorption has an effect that the deterioration of the contents due to oxygen can be remarkably suppressed as compared with a packaging material having merely gas barrier properties.

A food packaging material according to claim 16 of the present invention is, as described above, any one of claims 1 to 15.
It is a structure provided with the oxygen-absorbing packaging material described in the item.

Therefore, the above configuration has an effect that it is possible to provide a food packaging material which can be suitably used particularly for packaging of fresh foods and the like which are easily deteriorated rapidly by oxygen.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view showing a gas barrier layer of a laminate used as an oxygen-absorbing packaging material according to one embodiment of the present invention.

FIG. 2 is an X-ray diffraction graph of the inorganic layered compound for calculating the “unit thickness a” of the inorganic layered compound in the laminate.

FIG. 3 is an X-ray diffraction graph of an inorganic layered compound for calculating “plane spacing d” of the inorganic layered compound in the laminate.

FIG. 4 calculates the “plane spacing d” of the inorganic layered compound when the peak corresponding to the “plane spacing d” overlaps the halo (or background) and is difficult to detect in the graph of FIG. It is an X-ray diffraction graph at the time.

FIG. 5 is an explanatory view schematically showing a high-pressure dispersion process used in the production of the laminate.

FIG. 6 is a schematic sectional view showing an example of the laminate used as the oxygen-absorbing packaging material according to the present invention.

FIG. 7 is a schematic sectional view showing another example of the laminate used as the oxygen-absorbing packaging material according to the present invention.

[Explanation of symbols]

 Reference Signs List 1 base material 2 anchor layer 3 gas barrier layer 4 sealant layer

Claims (16)

[Claims] 1. An oxygen-absorbing packaging material for storing and packaging contents and having an oxygen-absorbing property for absorbing oxygen in contact with the contents, comprising a gas barrier layer comprising a resin composition having an inorganic layered compound. An oxygen-absorbing packaging material, comprising: a laminated body having the above-mentioned structure, wherein the surface in contact with the contents of the laminated body is provided with the oxygen-absorbing property. 2. The oxygen absorbing property is provided by encapsulating a deoxidizer between at least a gas barrier layer and a surface of the laminate in contact with the contents. Oxygen absorbing packaging material. 3. The oxygen-absorbing packaging material is a vertical pillow packaging bag,
Horizontal pillow packaging bag, gusset packaging bag, 3-side seal packaging bag,
4-side sealed packaging bag, pair of vacuum and compressed air molded container and lid,
At least one selected from a pair of an injection or press-molded container and a lid, a squeeze bottle, a standing pouch, a bag-in-box, a paper carton container, and a bottle
The oxygen-absorbing packaging material according to claim 1 or 2, wherein the oxygen-absorbing packaging material is processed into various kinds of packaging shapes. 4. The oxygen-absorbing packaging material according to claim 1, wherein the laminate further has at least one metal or metal oxide layer. 5. The laminate according to claim 1, further comprising at least one polyolefin resin layer.
5. The oxygen-absorbing packaging material according to any one of items 4 to 4. 6. The oxygen-absorbing packaging material according to claim 1, wherein the laminate further has at least one biaxially stretched film layer. 7. The oxygen-absorbing packaging material according to claim 1, wherein the oxygen permeability is 1 mL / m ² · day · atm or less. 8. The method according to claim 1, wherein said inorganic layered compound swells and cleaves in a dispersion medium.
The oxygen-absorbing packaging material according to the item. 9. The gas barrier layer according to claim 1, wherein the gas barrier layer is obtained by subjecting a mixed solution of a resin composition having an inorganic layered compound to a high-pressure dispersion treatment.
The oxygen-absorbing packaging material according to the item. 10. The high-pressure dispersion treatment is performed at 100 kgf / cm.
The oxygen-absorbing packaging material according to claim 9, which is processed under ^two or more pressure conditions. 11. An inorganic layered compound having an aspect ratio of 50.
The oxygen-absorbing wrapping material according to any one of claims 1 to 10, wherein the oxygen-absorbing wrapping material is within the range of -5000. 12. An inorganic layered compound having an aspect ratio of 200.
The oxygen-absorbing wrapping material according to any one of claims 1 to 11, wherein the oxygen-absorbing wrapping material is within the range of -3000. 13. The method according to claim 1, wherein the resin composition contains a high hydrogen bonding resin, and the weight ratio of the inorganic layered compound to the high hydrogen bonding resin is in the range of (1/100) to (100/1). The oxygen-absorbing packaging material according to any one of claims 1 to 12, wherein: 14. The oxygen-absorbing package according to claim 13, wherein the high hydrogen bonding resin has a molar percentage of hydrogen bonding groups or ionic groups per unit weight of the resin of 30% or more and 50% or less. Wood. 15. The oxygen according to claim 13, wherein the high hydrogen bonding resin is polyvinyl alcohol and a modified product thereof, or a polysaccharide, or an ethylene-vinyl alcohol copolymer and a modified product thereof. Absorbent packaging material. 16. A food packaging material comprising the oxygen-absorbing packaging material according to any one of claims 1 to 15.