Oxygen-absorbing laminate used in liquid paper containers

Abstract

PURPOSE: To provide a laminate used for a paper container for liquid, which has less generated odor and excellent barrier property to oxygen gas, absorbs oxygen in a content storage space to reduce the oxygen concentration and inhibits oxygen-induced deterioration of the content and has excellent balance of heat sealability, low odor property, low oxygen concentration, aroma retention, content resistance and filling and packaging properties, and to provide a packaging material and a paper container for liquid prepared using the laminate.SOLUTION: There is provided an oxygen absorbing laminate for a paper package used to prepare a paper package for liquid, which includes a layer structure obtained by laminating at least a paper base material layer, an oxygen barrier layer, an oxygen-absorbing adhesive layer and a sealant layer in this order, wherein the oxygen-absorbing adhesive layer is a layer formed from a specific oxygen-absorbing adhesive composition, and the oxygen-absorbing adhesive composition contains at least an oxygen absorbing compound and an oxidation accelerating catalyst.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to an oxygen-absorbing laminate for use in liquid paper containers, which has low odor generation, provides barrier properties against external oxygen gas and absorbs oxygen within the content storage space to suppress deterioration of the contents due to oxygen, and has an excellent balance of fragrance retention, content resistance, and heat sealability, making it suitable for filling and packaging, as well as an oxygen-absorbing packaging material and an oxygen-absorbing paper container made from the oxygen-absorbing laminate. [Background technology]

[0002] Traditionally, packaging methods to suppress the deterioration of the quality of contents such as food, medical products, chemical products, and cosmetics due to oxygen have included using packaging materials with high oxygen barrier properties, purging the contents with an inert gas such as nitrogen gas, or including oxygen absorbers packaged with reduced iron powder. However, these products have drawbacks such as insufficient performance, increased packaging costs, greater waste generation, performance only being effective in moist environments, and the risk of accidental ingestion. Furthermore, Patent Document 1 describes a packaging material using a resin that has oxygen-absorbing properties and produces little odor. However, this resin is polycyclododecene, which is insoluble in polar solvents and does not have active hydrogen groups, making it unsuitable as an adhesive raw material for packaging materials made of laminates. Furthermore, Patent Document 2 describes a laminating adhesive made of a resin using methyltetrahydrophthalic acid as an oxygen-absorbing raw material, but it has the disadvantage of having low oxygen absorption and being unstable. Patent Document 3 describes an oxygen-absorbing thermoplastic resin having a saturated five-membered ring with substituents containing carbon-carbon double bonds and repeating units consisting of -CH=CH- groups connecting the saturated five-membered rings. However, it has drawbacks such as poor solubility in solvents, making it difficult to use, and a strong odor. As gas barrier packaging materials including paper substrates, those having a gas barrier layer made of a water-soluble polymer and an inorganic layered compound on a paper substrate (hereinafter also referred to as "base paper") (Patent Documents 4 and 5), and those having a barrier layer made of a specific vinyl alcohol-based polymer on a coating layer (Patent Documents 5 and 6) have been disclosed. As water vapor barrier packaging materials including paper substrates, packaging paper having a moisture-proof layer made of synthetic resin latex, wax and inorganic fine particles has been disclosed (Patent Document 7). However, packaging materials made by laminating or bonding a paper base material (base paper) with a resin having gas barrier properties and a resin having water vapor barrier properties had problems in that they could not meet various quality requirements due to limitations in the types of resins that could be laminated. On the other hand, packaging materials that possess both gas barrier and water vapor barrier properties by coating a paper substrate (base paper) with a resin having gas barrier properties and a resin having water vapor barrier properties have fewer limitations on the types of resins that can be used, making it possible to meet various quality requirements. However, when a moisture-proof layer from Patent Document 7 is provided on top of a packaging material that has gas barrier properties, for example, the gas barrier packaging material from Patent Document 4 or Patent Document 5, there was a problem in that good water vapor barrier properties could be obtained, but gas barrier properties could not be obtained. Furthermore, even when a gas barrier layer from Patent Document 4 or Patent Document 5 was provided on top of the moisture-proof paper having a water vapor barrier layer from Patent Document 7, it was not possible to obtain sufficient balance between gas barrier and water vapor barrier properties. [Prior art documents] [Patent Documents]

[0003] [Patent Document 1] Patent No. 5873770 [Patent Document 2] Patent No. 5671816 [Patent Document 3] Patent No. 6505699 [Patent Document 4] Japanese Patent Publication No. 2009-184138 [Patent Document 5] Japanese Patent Application Laid-Open No. 2003-094574 [Patent Document 6] Japanese Patent No. 5331265 [Patent Document 7] Japanese Patent Application Laid-Open No. 2005-162213 [Summary of the Invention] [Problems to be Solved by the Invention]

[0004] The problems of the present invention are as follows: it has little generated odor, excellent barrier properties against oxygen gas, absorbs oxygen in the content accommodation space to lower the oxygen concentration and suppresses the deterioration of the content due to oxygen, and has an excellent balance of heat sealability, low odor property, low oxygen concentration, fragrance retention property, resistance to contents, and filling and packaging property. The present invention provides a laminate for use in a liquid paper container, a packaging material, and a liquid paper container produced using the laminate. [Means for Solving the Problems]

[0005] In order to solve the above problems, the present inventors have found that a laminate including at least a paper base material layer, an oxygen barrier layer, an oxygen-absorbing adhesive layer, and a sealant layer laminated in this order can solve the above problems. That is, the present invention is characterized by the following points. 1. An oxygen-absorbing laminate for a paper container for producing a liquid paper container, including at least a paper base material layer, an oxygen barrier layer, an oxygen-absorbing adhesive layer, and a sealant layer laminated in this order, The oxygen-absorbing adhesive layer is a layer formed from an oxygen-absorbing adhesive composition, The oxygen-absorbing adhesive composition contains at least an oxygen-absorbing compound and an oxidation-promoting catalyst, The oxygen-absorbing compound has one or more unsaturated five-membered rings, Any bond between five carbon atoms constituting the unsaturated five-membered ring is a carbon-carbon double bond, A monovalent and / or divalent or higher electron-donating organic group 1 is bonded to the unsaturated five-membered ring, If there is one unsaturated five-membered ring, the five-membered ring or the organic group 1 has a functional group having active hydrogen, or a group in which the active hydrogen of a functional group having active hydrogen is substituted with a monovalent organic group 2. If there are two or more unsaturated five-membered rings, the unsaturated five-membered rings are linked to each other via two or more divalent organic groups 2 that substitute for the active hydrogen of the active hydrogen group on each of the five-membered rings or on the organic group 1. Oxygen-absorbing laminate for paper containers. 2. The oxygen-absorbing adhesive layer and the sealant layer are further interposed, and a reinforcing layer is provided between them. The oxygen-absorbing laminate for paper containers described in item 1 above. 3. The paper substrate layer includes a coating resin layer on its surface. An oxygen-absorbing laminate for paper containers as described in 1 or 2 above. 4. The structure of the unsaturated five-membered ring, or the structure consisting of the unsaturated five-membered ring and organic group 1, is derived from one or more selected from the group consisting of cyclopentadiene, dicyclopentadiene, norbornene, and derivatives thereof. An oxygen-absorbing laminate for paper containers as described in any of the above 1 to 3. 5. The organic group 2 includes an isocyanate compound, or a structural component derived from an isocyanate compound and a hydroxyl group-containing compound. An oxygen-absorbing laminate for paper containers as described in any of the above 1 to 4. 6. The isocyanate compound is xylene diisocyanate, hexamethylene diiso It is one or more selected from the group consisting of cyanates, isophorone diisocyanates, toluene diisocyanates, diphenylmethane diisocyanates, and derivatives thereof. The oxygen-absorbing laminate for paper containers described in item 5 above. 7. The hydroxyl group-containing compound is one or more selected from the group consisting of polyhydric alcohols, polyolefin polyols, polyether polyols, polyester polyols, polycarbonate polyols, poly(meth)acrylic acid ester polyols, phenoxy resins, and urethane chain elongated polyols thereof. An oxygen-absorbing laminate for paper containers as described in item 5 or 6 above. 8. The organic group 2 does not have a crosslinking functional group. An oxygen-absorbing laminate for paper containers as described in any of items 1 to 7 above. 9. The organic group 2 has one or more crosslinkable functional groups, The crosslinkable functional group is a hydroxyl group and / or an isocyanate group. An oxygen-absorbing laminate for paper containers as described in any of items 1 to 7 above. 10. The oxygen-absorbing compound contains one or more compounds selected from the group consisting of compounds represented by the following formulas (1) to (4). An oxygen-absorbing laminate for paper containers as described in any of items 1 to 7 above. [ka] [ka] [ka] [ka] (In the formula, a to e are all numbers greater than or equal to 1, R 1 , R 2 , R 3 Each of these is an organic group having one or more carbon atoms, and includes at least an alkylene and / or phenylene structure, and may further include structures derived from one or more selected from the group consisting of polyhydric alcohols, polyolefin polyols, polyether polyols, polyester polyols, polycarbonate polyols, poly(meth)acrylic acid ester polyols, phenoxy resins, and urethane chain extension polyols thereof. 11. The oxygen-absorbing compound contains a compound represented by the following formula (5): An oxygen-absorbing laminate for paper containers as described in any of items 1 to 7 above. [ka] (In the formula, f is a number greater than or equal to 0, R 4 and R 5 Each of these is an organic group having one or more carbon atoms, and is an organic group containing at least an alkylene and / or phenylene structure. Furthermore, it may include structures derived from one or more selected from the group consisting of polyhydric alcohols, polyolefin polyols, polyether polyols, polyester polyols, polycarbonate polyols, poly(meth)acrylic acid ester polyols, phenoxy resins, and urethane chain extension polyols thereof. 12. The oxidation-promoting catalyst is a compound containing a cation made of a peroxide or a transition metal. An oxygen-absorbing laminate for paper containers, as described in any of items 1 to 11 above. 13. The compound containing the cation of the transition metal is a metal soap comprising a transition metal compound capable of releasing a cation or complex of the transition metal and an anion or ligand of a fatty acid. An oxygen-absorbing laminate for paper containers, as described in any of items 1 to 11 above. 14. The oxygen-absorbing adhesive composition further contains a modifier, The modifying agent is an isocyanate compound and / or a hydroxyl group-containing compound, wherein the oxygen-absorbing laminate for paper containers is as described in any of items 1 to 13 above. 15. The isocyanate compound is one or more selected from the group consisting of xylene diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, toluene diisocyanate, diphenylmethane diisocyanate, and derivatives thereof. The oxygen-absorbing laminate for paper containers described in item 14 above. 16. The hydroxyl group-containing compound comprises one or more selected from the group consisting of polyester polyols, poly(meth)acrylic acid ester polyols, polyalkylene ether diols, and urethane chain elongated polyols thereof. An oxygen-absorbing laminate for paper containers as described in item 13 or 14 above. 17. An oxygen-absorbing packaging material for paper containers, manufactured using an oxygen-absorbing laminate for paper containers as described in any of items 1 to 16 above. 18. An oxygen-absorbing paper container for liquids made using the oxygen-absorbing packaging material for paper containers described in item 17 above, The oxygen barrier layer is a layer located outside the oxygen-absorbing adhesive layer. Oxygen-absorbing paper container for liquids. [Effects of the Invention]

[0006] According to the present invention, it is possible to obtain a laminate for use in liquid paper containers that has low odor generation, excellent barrier properties against oxygen gas, absorbs oxygen in the content storage space to lower the oxygen concentration and suppress oxygen-induced deterioration of the contents, and has an excellent balance of heat sealability, low odor, low oxygen concentration, aroma retention, content resistance, and fillable packaging properties, as well as packaging materials and liquid paper containers made using the laminate. Furthermore, the packaging material produced from the laminate of the present invention is particularly suitable for flexible packaging applications, achieving shorter packaging processes, reduced costs, and lighter packaging. Since the packaging does not require the inclusion of an oxygen absorber, which was previously included, it eliminates the risk of accidental ingestion of the oxygen absorber and reduces the amount of waste generated from the oxygen absorber. [Brief explanation of the drawing]

[0007] [Figure 1] This is a cross-sectional view showing one example of the layer structure of the oxygen-absorbing laminate for paper containers of the present invention. [Figure 2] This is a cross-sectional view showing another example of the layer structure of the oxygen-absorbing laminate for paper containers of the present invention. [Figure 3] This is a perspective view showing an example of an oxygen-absorbing paper container of the present invention. [Figure 4] Figure 3 is a front view showing a blank plate used in the manufacture of oxygen-absorbing paper containers. [Modes for carrying out the invention]

[0008] The present invention will be described in more detail below. The following description of the constituent elements is an example of an embodiment of the present invention, and the present invention is not limited to these contents unless it exceeds the gist of the invention. In this invention, the terms "film" and "sheet" are considered synonymous.

[0009] <Oxygen-absorbing laminate for paper containers> The oxygen-absorbing laminate for paper containers of the present invention is a laminate used in liquid paper containers, and includes a layer structure in which at least a paper base layer, an oxygen barrier layer, an oxygen-absorbing adhesive layer, and a sealant layer are laminated in this order. Preferably, a reinforcing layer is further provided between the oxygen-absorbing adhesive layer and the sealant layer. When forming an oxygen-absorbing paper container for liquids (hereinafter sometimes referred to as a liquid paper container or oxygen-absorbing paper container) using an oxygen-absorbing packaging material for paper containers (hereinafter sometimes referred to as an oxygen-absorbing packaging material) made from an oxygen-absorbing laminate for paper containers (hereinafter sometimes referred to as an oxygen-absorbing laminate), the sealant layer is heat-sealed, and the oxygen barrier layer is located outside the oxygen-absorbing adhesive layer of the liquid oxygen-absorbing paper container. By positioning the oxygen barrier layer outside the oxygen-absorbing adhesive layer, the amount of oxygen passing through the oxygen-absorbing paper container for liquids from the outside is reduced, and the efficiency of the oxygen-absorbing adhesive layer in absorbing oxygen in the contents storage space and reducing the oxygen concentration can be increased.

[0010] The oxygen-absorbing laminate for paper containers may include layers with various other functions as needed. For example, it may have other base material layers or printed layers, and may include reinforcing layers to satisfy various conditions such as deformation resistance, drop impact resistance, pinhole resistance, heat resistance, sealing performance, quality preservation, workability, hygiene, and so on. Furthermore, it can also have a functional layer to enhance oxygen gas barrier properties, provide barrier properties against water vapor, preserve the aroma of the contents being filled and packaged, or prevent the contents from changing in taste or developing an unpleasant odor. Furthermore, the above-mentioned materials may include adhesive resin layers between or within each layer to improve interlayer adhesion.

[0011] [Contents] In the above, the contents are liquids, and examples include beverages, alcoholic beverages such as sake and wine, soups, seasonings, shampoos, cosmetics, and others.

[0012] <Regarding each layer that makes up the oxygen-absorbing laminate for paper containers> ≪Oxygen Barrier Layer≫ The oxygen barrier layer is a layer in an oxygen-absorbing paper container for liquids, made from an oxygen-absorbing laminate for paper containers, that suppresses the permeation of oxygen through the liquid oxygen-absorbing paper container from the outside to the internal contents storage area. In an oxygen-absorbing paper container for liquids, the oxygen barrier layer is located outside the oxygen-absorbing adhesive layer, thereby suppressing the permeation of oxygen from the outside of the liquid oxygen-absorbing paper container. This enhances the effect of the oxygen-absorbing adhesive layer in absorbing oxygen in the contents of the liquid oxygen-absorbing paper container and lowering the oxygen concentration. Various oxygen barrier materials can be used for the oxygen barrier layer. Furthermore, the oxygen barrier material may also possess gas barrier properties against water vapor, light-shielding properties against sunlight, and fragrance-retaining properties for the contents. Additionally, barrier materials possessing gas barrier properties against water vapor, light-shielding properties against sunlight, and fragrance-retaining properties for the contents may be used in combination.

[0013] Specifically, the oxygen barrier material described above can be one or more selected from the group consisting of, for example, metal foil, resin film with an inorganic vapor deposition layer, and resin coating film or resin film made of an oxygen barrier resin. Examples of inorganic compounds for the inorganic vapor deposition layer include metals, metal oxides, metal nitrides, metal carbides, etc. Among these, in particular, any one of a resin film with a metal vapor deposition layer, a resin film with a metal oxide vapor deposition layer, a resin coating film made of a barrier resin, or a resin film is preferable because it has excellent barrier properties such as oxygen gas, water vapor, light shielding property, fragrance retention property, etc., and has the advantage of being environmentally friendly in terms of the disposal surface of the container.

[0014] Specific examples of the metal foil include aluminum foil. The thickness of the aluminum foil is preferably 4 μm to 40 μm, more preferably 6 μm or more and 12 μm or less, and even more preferably 7 μm or more and 9 μm or less. Specific examples of the metal element constituting the above inorganic compound include, for example, aluminum (Al), silicon (Si), magnesium (Mg), calcium (Ca), potassium (K), tin (Sn), sodium (Na), boron (B), titanium (Ti), lead (Pb), zirconium (Zr), yttrium (Y), zinc (Zn), vanadium (V), barium (Ba), chromium (Cr), etc.

[0015] Specific examples of the inorganic compound preferably include metals, metal oxides, metal nitrides, metal carbides, etc. composed of the above metal elements. In addition to these, indium tin oxide (ITO), SiO x C y films and other composite inorganic compounds such as those produced by chemical vapor deposition method are also included. Specific examples of the inorganic compound of the inorganic vapor deposition layer include silicon nitride, silicon carbide, etc. Among these, silica and alumina are preferable.

[0016] [[ID=()]]The notation of the average composition of the inorganic compound is, for example, SiO x , AlO x , SiO x C<();>etc., such as MO x , MO x C y (However, in the formula, M represents a metal element, and the values of x and y depend on the metal element Each has a different range.) In the case of metal oxides, the range of X values ​​is as follows: silicon: 0-2, aluminum: 0-1.5, magnesium: 0-1, calcium: 0-1, potassium: 0-0.5, tin: 0-2, sodium: 0-0.5, boron: 0-1, 5, titanium: 0-2, lead: 0-1, zirconium: 0-2, yttrium: 0-1.5. The above MO X In this case, when x=0, it is metallic and not transparent, and in the range of x The upper limit is the value when it is completely oxidized. In the present invention, silicon dioxide and aluminum oxide are preferably used, with silicon dioxide having an x ​​value in the range of 1.0 to 2.0 and aluminum oxide having an x ​​value in the range of 0.5 to 1.5. The oxygen barrier layer may be formed from one of these barrier materials, or from a combination of two or more materials, or from a mixture of two or more materials. It may also consist of a single layer, or from multiple layers of the same or different compositions, and in the case of multiple layers, they do not have to be laminated adjacent to each other.

[0017] As the resin film supporting the inorganic vapor deposition layer, a resin film can be used that has excellent mechanical, physical, chemical, and other properties, and is particularly strong, tough, and heat-resistant, because it is provided with an inorganic vapor deposition layer.

[0018] Specifically, in the present invention, the resin film supporting the inorganic vapor deposition layer can be, for example, polyester resin films such as polyethylene terephthalate (PET) and polybutylene terephthalate (PBT), polyamide resin films such as various types of nylon, polyethylene resins, polypropylene resins, cyclic polyolefin resins, polystyrene resins, acrylonitrile-styrene copolymers (AS resins), acrylonitrile-butadiene-styrene copolymers (ABS resins), polyolefin films such as polybutene resin films, polyvinyl chloride resins, polycarbonate resins, polyimide resins, polyamide-imide resins, polyarylphthalate resins, silicone resins, polysulfone resins, polyphenylene sulfide resins, polyethersulfone resins, polyurethane resins, cellulose resins, poly(meth)acrylic resins, polyvinylidene chloride films, acetal resin films, fluororesins, and others. In the present invention, it is preferable that the resin film be made of biaxially oriented polyethylene terephthalate, polyacrylonitrile, ethylene-vinyl alcohol copolymer, unoriented polypropylene (CPP), low-density polyethylene, linear low-density polyethylene, etc., which can be heat-sealed or bonded with an adhesive. Furthermore, the resin film used in the vapor-deposited resin film may also be the resin film that constitutes the base layer.

[0019] As a method for forming an inorganic vapor-deposited layer, an inorganic vapor-deposited layer can be formed on a resin film using the inorganic compounds mentioned above as raw materials, for example, by physical vapor deposition (PVD) methods such as vacuum deposition, sputtering, ion plating, and cluster ion beam deposition, or by chemical vapor deposition (CVD) methods such as plasma chemical vapor deposition, thermochemical vapor deposition, and photochemical vapor deposition.

[0020] To explain in more detail, in the PVD method described above, for example, a winding type deposition machine is used, and the resin film coming out of the unwinding roll is placed into the deposition chamber in a vacuum chamber, where the deposition source heated in the crucible is evaporated, and if necessary, oxygen is blown out from an oxygen outlet, and an inorganic deposition layer is formed on the resin film on the cooled coating drum via a mask, and then the resin film on which the inorganic deposition layer has been formed is wound onto a winding roll, thereby producing the inorganic deposition layer-coated resin film according to the present invention.

[0021] On the other hand, in the above-described CVD method, a mixed gas consisting of, for example, an organosilicon compound as a monomer gas, oxygen gas, an inert gas, etc., supplied from a vapor deposition raw material volatilization supply device, is introduced onto the resin film surface unwound from an unwinding roll placed in the vapor deposition chamber, and on the surrounding surface of the electrode drum, thereby producing a resin film in which a silicon oxide vapor deposition layer is formed by plasma.

[0022] In the above, the thickness of the inorganic vapor-deposited layer is preferably 30 Å to 3000 Å, more preferably 40 Å to 2500 Å, and even more preferably 50 Å to 2000 Å in order to obtain sufficient oxygen barrier properties. More specifically, in the PVD method described above, the thickness of the inorganic vapor-deposited layer made of aluminum oxide is preferably 30 Å to 1000 Å, and more preferably 50 Å to 500 Å. Furthermore, in the above CVD method, the thickness of the inorganic vapor-deposited layer made of silicon dioxide is 30 Å to 3 000 Å is preferred, and 100 Å to 300 Å is more preferred. In general, in the case of inorganic vapor-deposited layers consisting of metal oxides and inorganic materials, if the thickness of the inorganic vapor-deposited layer exceeds the above range, there is a risk that cracks will easily form in the inorganic vapor-deposited layer, thereby reducing its barrier properties, and it also has the problem of increasing material costs, which is undesirable. On the other hand, if it is below the above range, it is difficult to achieve oxygen barrier properties, which is also undesirable.

[0023] An oxygen barrier resin coating film or oxygen barrier resin film made of an oxygen barrier resin can also be used as an oxygen barrier material, and at the same time can exhibit gas barrier properties against water vapor, fragrance retention, etc. As oxygen barrier resins, for example, films or coatings of resins with excellent gas barrier properties such as polyvinylidene chloride (PVDC), polyester resins, polyamide resins (especially aromatic polyamides such as nylon MXD6), ethylene-vinyl alcohol copolymer (EVOH) with an ethylene content of 25 mol% to 50 mol%, obtained by completely saponifying ethylene-vinyl acetate copolymer (vinyl acetate content of approximately 79 wt% to 92 wt%), polyvinyl alcohol, polyacrylonitrile, and others can be used. The thickness of the oxygen barrier resin coating film or oxygen barrier resin film is arbitrary, but preferably 0.5 μm to 300 μm, and more preferably 1 μm to 100 μm. Furthermore, the resin film with the inorganic vapor deposition layer preferably has a water vapor transmission rate of 3.0 g / m², as measured in accordance with the JIS K7129 method under conditions of 40°C and 100% RH. 2 · Less than 2.0 g / m² 2 • less than or equal to day, and more preferably less than or equal to day. It is 1.5g / m 2 • less than or equal to day. If the water vapor permeability meets the above numerical range, the packaging This effectively prevents water vapor from entering the contents-containing section inside the packaging from the outside. Furthermore, the resin film with the inorganic vapor deposition layer preferably has an acidity transmittance of 1.0 cc / m², as measured in accordance with the JIS K7126 method under conditions of 23°C and 90% RH. 2 ·a It is less than or equal to tm·day, and more preferably 0.5cc / m 2 •atm•day is below More preferably 0.1 cc / m³ 2 The oxygen permeability is less than or equal to the above number of atm·day. If the value range is met, the intrusion of oxygen from the outside of the packaging into the contents-containing section inside the packaging can be sufficiently suppressed.

[0024] When forming the above inorganic vapor-deposited layer, SiO x Pretreatment such as plasma is performed on the resin to be deposited. By cleaning the surface of the film and generating polar groups and free radicals on its surface, the adhesion between the inorganic vapor-deposited layer and the resin film can be improved. Furthermore, when a plasma chemical vapor deposition apparatus consisting of at least two deposition chambers is used to continuously deposit two or more inorganic vapor-deposited layers, each layer can be deposited to have high gas barrier properties, thereby achieving even higher gas barrier properties than a single layer. Moreover, by continuously depositing the layers without opening them to the atmosphere, it is possible to prevent foreign matter, dust, etc., which can cause cracks from entering between the inorganic vapor-deposited layers, and the gas barrier properties are further improved. Furthermore, by using different compositions for each vapor-deposited layer, the inorganic vapor-deposited layers are distinct discontinuous layers, which allows for more efficient suppression of the permeation of oxygen gas, water vapor, and other elements.

[0025] When forming an oxygen barrier layer with a resin film with an inorganic vapor deposition layer, the inorganic vapor deposition layer surface can be bonded to the substrate layer via an adhesive resin layer and then laminated. Furthermore, when laminating resin films with inorganic vapor deposition layers, if necessary, a surface treatment layer can be formed by pre-treating the surface of the resin film with inorganic vapor deposition layers with physical surface treatments such as corona discharge treatment, ozone treatment, plasma treatment, glow discharge treatment, or sandblasting, or with chemical surface treatments such as oxidation treatment using chemicals, in order to strengthen the adhesive strength with other layers.

[0026] ≪Oxygen-absorbing adhesive layer≫ The oxygen-absorbing adhesive layer is a layer formed using an oxygen-absorbing adhesive composition.

[0027] Oxygen-absorbing adhesive composition The oxygen-absorbing adhesive composition of the present invention is an oxygen-absorbing adhesive composition that contains at least an oxygen-absorbing compound and an oxidation-promoting catalyst. The oxygen-absorbing adhesive composition may, if necessary, further contain modifiers, diluents, various additives, etc.

[0028] The oxygen-absorbing adhesive composition may be prepared by adding an oxygen-absorbing compound to an existing adhesive composition, or by preparing an oxygen-absorbing adhesive composition using an oxygen-absorbing compound as a resin component. Here, the existing oxygen-absorbing adhesive composition may be a one-component oxygen-absorbing adhesive composition or a two-component oxygen-absorbing adhesive composition. The oxygen-absorbing adhesive composition may contain one or more oxygen-absorbing compounds. The oxygen-absorbing adhesive composition and / or the existing adhesive compositions described above may be curable or non-curable. If curable, it may be thermosetting, photocuring, electron beam curing, or any other type. The oxygen-absorbing compound may react with components contained in existing adhesive compositions, or it may not react with them. Furthermore, the oxygen-absorbing compounds may react with each other. Depending on the presence or absence of the above reaction and the type of reaction, one or more oxygen-absorbing compounds can be selected and used from those that do not have functional groups, those that have (co)polymerizable functional groups, and those that have functional groups that can react as a main agent or curing agent.

[0029] Specifically, for example, an oxygen-absorbing compound without a functional group and / or an oxygen-absorbing compound having a functional group can be added to a two-component urethane adhesive composition containing an isocyanate compound and a hydroxyl group-containing compound. In this case, isocyanate groups and / or hydroxyl groups are preferred as the functional groups. For example, an oxygen-absorbing adhesive composition can be prepared by combining the main component and curing agent of the oxygen-absorbing adhesive composition with an isocyanate compound and an oxygen-absorbing compound having a hydroxyl group, or with a hydroxyl group-containing compound and an oxygen-absorbing compound having an isocyanate group, or with an oxygen-absorbing compound having a hydroxyl group and an oxygen-absorbing compound having an isocyanate group. The oxygen-absorbing adhesive composition is preferably a urethane-based oxygen-absorbing adhesive composition.

[0030] The solid content in the oxygen-absorbing adhesive composition is not particularly limited, but is preferably 20% by mass or more and 100% by mass or less.

[0031] The content of the oxygen-absorbing compound in the solid content of the oxygen-absorbing adhesive composition, excluding the oxidation-promoting catalyst, is preferably 40% by mass or more and 100% by mass or less. If the content is less than the above range, there is a risk that the oxygen absorption will be insufficient. In the case of 100% by mass, this refers to cases where the oxygen-absorbing compound can be used as a resin component of the adhesive composition, and it may have sufficient adhesive properties on its own, or it may have functional groups that allow it to be cured on its own, or it may be used in combination with an oxygen-absorbing compound having functional groups that act as a curing agent.

[0032] The content of the oxidation-promoting catalyst in the oxygen-absorbing adhesive composition is preferably 10 ppm or more and 6000 ppm or less relative to the oxygen-absorbing compound. If the content is lower than the above range, oxygen absorption may be insufficient, and if the content is higher If the amount exceeds the specified range, the oxygen absorption capacity tends to become unstable, and the oxygen absorption capacity may be consumed before the packaging is made, potentially impairing the effect of suppressing oxygen-induced deterioration of the packaging contents after the packaging is made.

[0033] [Oxygen-absorbing compounds] The oxygen-absorbing compound of the present invention has oxygen-absorbing properties, produces little odor, can be used alone, or can be mixed with resins or resin compositions. The oxygen-absorbing compound of the present invention is an unsaturated five-membered ring-containing compound having one or more unsaturated five-membered rings, wherein any bond between the five carbon atoms constituting the unsaturated five-membered ring is a carbon-carbon double bond, and a monovalent and / or divalent or more electron-donating organic group 1 is bonded to the unsaturated five-membered ring. When there is one unsaturated five-membered ring, the five-membered ring or the organic group 1 has a functional group having an active hydrogen, or a group in which the active hydrogen of a functional group having an active hydrogen is substituted with a monovalent organic group 2. When there are two or more unsaturated five-membered rings, the unsaturated five-membered rings are linked to each other via a divalent or higher organic group 2 that substitutes for the active hydrogen of the active hydrogen group on each of the organic groups 1. When there are two or more of the unsaturated five-membered rings in one molecule, the unsaturated five-membered rings are linked to each other via a structure in which the active hydrogen of each five-membered ring or functional group having active hydrogen on organic group 1 is substituted with organic group 2 with a valency of 2 or higher. Each of the unsaturated five-membered rings, organic group 1, and organic group 2 present in one molecule may be of one type or two or more types, and the number of each may be one or two or more. Furthermore, the number of organic group 1 bonded to one of the unsaturated five-membered rings may be one or two or more. Moreover, the oxygen-absorbing compound may be a mixture of molecules with two or more structures in which the types and numbers of each of the unsaturated five-membered rings, organic group 1, and organic group 2 present in one molecule differ as described above.

[0034] When organic group 1 donates electrons to the unsaturated five-membered ring, the electron density of the carbon-carbon double bond portion of the unsaturated five-membered ring increases, leading to increased reactivity with oxygen and improved oxygen absorption. It is preferable that the unsaturated five-membered ring does not have an electron-withdrawing group attached to it. The presence of an electron-withdrawing group reduces the electron density of the carbon-carbon double bond portion of the unsaturated five-membered ring, decreasing its reactivity with oxygen and reducing its oxygen absorption capacity. Specific molecular structures of oxygen-absorbing compounds include, for example, a structure in which one unsaturated five-membered ring is bonded to a monovalent or divalent organic group 1; a structure in which one unsaturated five-membered ring is bonded to a monovalent or divalent organic group 1 and a monovalent organic group 2 in that order; a structure in which two unsaturated five-membered rings are bonded via a divalent organic group 1 and a divalent organic group 2; and a structure in which three unsaturated five-membered rings are bonded via a divalent organic group 1 and a trivalent organic group 2.

[0035] Furthermore, oxygen-absorbing compounds do not necessarily have crosslinking functional groups, but they may have them. The crosslinkable functional group may be a functional group that was present in the compound from which organic group 2 was derived, or it may be a functional group that was added by chemical modification. Because the oxygen-absorbing compound has a crosslinking functional group, when the oxygen-absorbing compound is mixed with a resin or resin composition, the compatibility of the oxygen-absorbing compound with the resin or resin composition is increased, or the oxygen-absorbing compound becomes part of the crosslinked structure of the resin or resin composition, making it less likely to bleed from the resin or resin composition or the cured resin composition, thereby increasing the content of the oxygen-absorbing compound in the resin or resin composition. Specific examples of crosslinkable functional groups include aliphatic hydroxyl groups, aromatic hydroxyl groups, isocyanate groups, amino groups, epoxy groups, and (meth)acrylic groups. Among these, isocyanate groups and aliphatic hydroxyl groups are preferred. When a crosslinkable functional group is present, the number of crosslinkable functional groups in the oxygen-absorbing compound is preferably one or two or more per molecule. Furthermore, only one type of crosslinkable functional group is contained in each molecule. However, it is also acceptable to have two or more types. There are no particular restrictions on the functional group equivalent of the crosslinkable functional group, but it is preferably 500 to 20000, more preferably 1000 to 15000, and even more preferably 1500 to 10000.

[0036] The number-average molecular weight of the oxygen-absorbing compound is preferably 100 to 10,000, more preferably 200 to 5,000, and even more preferably 300 to 2,500. If the number-average molecular weight is smaller than the above range, precipitation is likely to occur when mixed with resins or resin compositions. If the number-average molecular weight is larger than the above range, when mixed with resins or resin compositions, the viscosity of the mixture increases, making it necessary to include a large amount of diluent, which makes it difficult to obtain a thick film or layer, and tends to worsen coating suitability.

[0037] Furthermore, the oxygen absorption effect of the oxygen-absorbing compound of the present invention can be enhanced by heating or the addition of a catalyst.

[0038] (unsaturated five-membered ring) The unsaturated five-membered rings of oxygen-absorbing compounds have carbon-carbon double bonds within them. Here, the carbon-carbon double bond is any bond between the five carbon atoms constituting the unsaturated five-membered ring, and there may be one or two such bonds within a single unsaturated five-membered ring. Oxygen-absorbing compounds exhibit oxygen-absorbing properties when the carbon-carbon double bond reacts with oxygen molecules in the air and incorporates them. Examples of compounds from which the unsaturated five-membered ring or the unsaturated five-membered ring to which the electron-donating organic group 1 is attached can be found include cyclopentadiene, dicyclopentadiene, norbornene, and their derivatives. The oxygen-absorbing compound may have an unsaturated five-membered ring derived from one or more compounds selected from the group consisting of these. The concentration of unsaturated five-membered rings in the oxygen-absorbing compound is not particularly limited, but is preferably between 1% by mass and 70% by mass, and more preferably between 5% by mass and 60% by mass. If the concentration is lower than the above range, the oxygen absorption tends to be insufficient, and it is difficult to obtain an oxygen-absorbing compound with a concentration higher than the above range, and the balance of various physical properties tends to be poor.

[0039] (Electron-donating organic group 1) Specific examples of organic group 1 include alkyl groups, alkylene groups, and cyclic alkylene groups. Among these, cyclic alkylene groups are preferred, and those that form an aliphatic bicyclic alkylene group together with the unsaturated five-membered ring are even more preferred. Specific examples of cyclic alkylene groups include cyclopropylene, cyclobutylene, cyclopentylene, cyclohexylene, cycloheptylene, and cyclooctylene. Among these, the cyclopentylene group is more preferred.

[0040] (Electron-withdrawing organic group) Specific examples of electron-withdrawing groups include, for example, phenyl groups, phenylene groups, carbonyl groups, halogens, and so on. Indene and coumarone, in which only these electron-withdrawing groups are bonded to an unsaturated five-membered ring, have a lower electron density in the carbon-carbon double bond portion of the unsaturated five-membered ring, resulting in reduced reactivity with oxygen and low oxygen absorption.

[0041] (Functional group containing active hydrogen) Functional groups containing active hydrogen are chemically reactive. Specific functional groups having active hydrogen include primary amino groups, secondary amino groups, aliphatic hydroxyl groups, aromatic hydroxyl groups, imino groups, carboxyl groups, urethane groups, and urea groups. Among these, primary amino groups, secondary amino groups, aliphatic hydroxyl groups, and aromatic hydroxyl groups are preferred, with aliphatic hydroxyl groups being more preferred.

[0042] (organic group 2) Organic group 2 is a monovalent and / or divalent or more group that is bonded to the five-membered ring or organic group 1, and substitutes the active hydrogen of the functional group having the active hydrogen on the five-membered ring or organic group 1. When there are two or more of these unsaturated five-membered rings in one molecule, the unsaturated five-membered rings are bonded to each other via a structure in which the active hydrogen of a functional group having active hydrogen is substituted with two organic groups of 2 or more valents. For example, a functional group having an active hydrogen on organic group 1 reacts with an isocyanate group of an isocyanate compound having a structural portion from which organic group 2 originates, so that the active hydrogen is substituted onto organic group 2 and bonded by a urethane group. The presence of two organic groups allows the oxygen-absorbing compound to have two or more of these unsaturated five-membered rings in a single molecule, further enhancing the compatibility, dispersibility, and reactivity when mixed with resins or resin compositions to prepare a mixture. Moreover, it can soften the mixture and the cured product thereof.

[0043] Organic group 2 may be an aliphatic group, an aromatic group, or may have both an aliphatic and an aromatic group. The organic group 2 present in one molecule of an oxygen-absorbing compound may be one type or two or more types. Organic group 2 is preferably a group that includes a structural part derived from an isocyanate compound and / or a hydroxyl group-containing compound. Here, the structural part derived from an isocyanate compound and / or a hydroxyl group-containing compound also includes a structural part derived from a reaction product between an isocyanate compound and a hydroxyl group-containing compound.

[0044] (Isocyanate compounds) Examples of isocyanate compounds from which the above-mentioned organic group 2 is derived include tetramethylene diisocyanate, hexamethylene diisocyanate, lysine diisocyanate, isophorone diisocyanate, norbornane diisocyanate, xylene diisocyanate, toluene diisocyanate, diphenylmethane diisocyanate, phenylene diisocyanate, diphenyl ether diisocyanate, hydrogenated diphenylmethane diisocyanate, polymethylene polyphenyl polyisocyanate, and their trimethylolpropane adducts, biuret compounds, allophanates, isocyanurates (trimers), and various derivatives thereof. Among these, biuret compounds of toluene diisocyanate, isophorone diisocyanate, and hexamethylene diisocyanate are preferred. In the present invention, one or more compounds selected from the group consisting of these isocyanate compounds can be used as the source of the monovalent and / or divalent or greater hydrocarbon group structural part. When two or more compounds are used, the two compounds may be used in the same molecule of the oxygen-absorbing compound, or molecules of oxygen-absorbing compounds having one different compound may be mixed.

[0045] The number-average molecular weight of the isocyanate compound is preferably 100 to 10,000, and more preferably 160 to 5,000. If the number-average molecular weight is smaller than the above range, precipitation is likely to occur when mixed with resins or resin compositions. If the number-average molecular weight is larger than the above range, when mixed with resins or resin compositions, the viscosity of the mixture increases, making it necessary to include a large amount of diluent, which makes it difficult to obtain a thick film or layer, and tends to worsen coating properties.

[0046] (Hydroxy group-containing compound) The hydroxyl group-containing compound is the compound from which the above-mentioned organic group 2 is derived, and has two or more hydroxyl groups. Examples of hydroxyl group-containing compounds include polyhydric alcohols, polyolefin polyols, polyether polyols, polyester polyols, polycarbonate polyols, poly(meth)acrylic acid ester polyols, phenoxy resins, and urethane chain extension polyols thereof. Among these, polyether polyols and polyolefin polyols are preferred. To prevent odor generation, hydroxyl group-containing compounds are preferably those that do not have double bonds in the aliphatic chain of the main skeleton, or those with two hydroxyl groups. While compounds with hydroxyl groups at the terminals are preferable because they are more readily available, it is not necessary for them to have them at the terminals. In the present invention, one or more compounds selected from the group consisting of these can be used as the hydroxyl group-containing compound from which the above-mentioned organic group 2 is derived. When two or more compounds are used, the two compounds may be used in the same molecule of the oxygen-absorbing compound, or molecules of oxygen-absorbing compounds having one different compound may be mixed. The number-average molecular weight of the hydroxyl group-containing compound is preferably 500 to 10000, more preferably 750 to 5000, and even more preferably 1000 to 3000. If the number-average molecular weight is smaller than the above range, precipitation is likely to occur when mixed with resins or resin compositions. If the number-average molecular weight is larger than the above range, when mixed with resins or resin compositions, the viscosity of the mixture increases, making it necessary to include a large amount of diluent, which makes it difficult to obtain thick films or layers, and tends to worsen coating properties.

[0047] • Polyhydric alcohols Polyhydric alcohols are monomers that have two or more hydroxyl groups. Specific examples of polyhydric alcohols include ethylene glycol, propylene glycol, 1,3-propanediol, 1,4-butanediol, 1,3-butanediol, 1,6-hexanediol, cyclohexanedimethanol, 1,8-octanediol, 1,9-nonanediol, neopentyl glycol, 3-methyl-1,5-pentanediol, 2-methyl-1,3-propanediol, 2,2,4-trimethyl-1,3-pentanediol, 2,4-diethyl-1,5-pentanediol, 1,12-octadecanediol, 2,2'-oxydiethanol, and other diols, as well as glycerin, mannitol, sorbitol, and others. Among the above, ethylene glycol is preferred in terms of oxygen absorption.

[0048] • Polyolefin polyol Polyolefin polyols are polyolefin resins having two or more hydroxyl groups. Specific examples of polyolefin polyols include those whose main skeleton is a polyolefin such as polyethylene, polypropylene, polybutylene, polybutadiene, hydrogenated polybutadiene, polyisoprene, hydrogenated polyisoprene, ethylene-vinyl acetate copolymer, ethylene-(meth)acrylate ethyl copolymer, ethylene-(meth)acrylic acid copolymer, or ethylene-propylene copolymer, and which also have hydroxyl groups. Among these, those with an ethylene-vinyl acetate copolymer or a hydrogenated polyisoprene as the main backbone are particularly preferred.

[0049] • Polyether polyol Polyether polyols are polyether-based resins having two or more hydroxyl groups. Polyether polyols are obtained, for example, by dehydrating and condensing the above-mentioned polyhydric alcohols or polyolefin polyols, and have a polyether structure as their main skeleton and also contain hydroxyl groups. Specific examples of polyether polyols include diethylene glycol, triethylene glycol, dipropylene glycol, polyethylene ether diol, polypropylene ether diol, polybutylene ether diol, and glycerin-modified polyether polyols. Among these, polypropylene ether diol is particularly preferred.

[0050] • Polyester polyol Polyester polyols are polyester resins having two or more hydroxyl groups. Polyester polyols are obtained, for example, by esterification reactions of various polycarboxylic acids or their derivatives with the above-mentioned polyhydric alcohols, polyolefin polyols, polyether polyols, etc., and have a polyester structure as their main backbone and also contain hydroxyl groups. Specific examples of polycarboxylic acids include adipic acid, phthalic acid, isophthalic acid, terephthalic acid, maleic acid, fumaric acid, succinic acid, oxalic acid, malonic acid, pimelic acid, azelaic acid, sebacic acid, suberic acid, glutaric acid, 1,4-cyclohexanedicarboxylic acid, trimellitic acid, etc. Derivatives of these polycarboxylic acids include esterified products, acid anhydrides, acylated products, etc. Among the above, polyester polyols that use two or more polyhydric alcohols and two or more polyhydric carboxylic acids in combination are preferred in order to reduce crystallinity.

[0051] • Polycarbonate polyol Polycarbonate polyols are polycarbonate-based resins having two or more hydroxyl groups. Polycarbonate has a polyol-derived portion in its main skeleton, and this polyol-derived portion may be derived from the above-mentioned polyhydric alcohols, polyolefin polyols, polyether polyols, polyester polyols, etc. Among these, polycarbonate polyols that use two or more polyhydric alcohols in combination are preferred in order to reduce crystallinity.

[0052] • Poly(meth)acrylic acid ester polyol Poly(meth)acrylic acid ester polyols are (meth)acrylic acid ester (co)polymers having two or more hydroxyl groups. Poly(meth)acrylic acid ester polyols can be obtained, for example, by polymerizing hydroxyl group-containing monomers such as 2-hydroxyethyl methacrylate or (meth)acrylic acid esters having a hydroxyl group synthesized from one (meth)acrylic acid molecule or its derivative and one diol, or by copolymerizing these monomers with each other or with (meth)acrylic acid esters that do not have a hydroxyl group. When synthesizing (meth)acrylic acid esters having hydroxyl groups, the diols used can be the above-mentioned diols, polyolefin polyols, polyether polyols, and the like. Among these, poly(meth)acrylic acid ester copolymers using 2-hydroxyethyl methacrylate are preferred.

[0053] Phenoxy resin Phenoxy resin is a resin obtained by reacting a polyvalent phenol compound with a polyvalent epoxy compound, and has a structure in which an aliphatic hydroxyl group is generated at the bond formed by the reaction of an aromatic hydroxyl group and an epoxy group. Phenoxy resins that are readily available and commonly produced are those obtained by reacting bisphenols with diglycidyl etherified bisphenols. Examples of polyvalent phenol compounds include bisphenol A and bisphenol F, while examples of polyvalent epoxy compounds include bisphenol A diglycidyl ether and bisphenol F diglycidyl ether. Among these, phenoxy resin using bisphenol A is preferred. The end of the phenoxy resin may be an aromatic hydroxyl group or an epoxy group.

[0054] • Urethane chain elongated polyol Urethane chain elongated polyols are formed by elongating the above hydroxyl group-containing compound with urethane chains. This is a polyol having two or more hydroxyl groups, obtained by [method / process]. Polyols with extended urethane chains can be obtained, for example, by polymerizing the various hydroxyl group-containing compounds mentioned above with the isocyanate compounds mentioned above to extend the urethane chains. Alternatively, diamines or amino alcohols may be used in combination during polymerization as needed. Among the above, urethane chain elongated polyols obtained by reacting the above-mentioned hydroxyl group-containing compounds, which have hydroxyl groups at both ends, with diisocyanate compounds are preferred.

[0055] (Specific examples of oxygen-absorbing compounds) The following are examples of specific oxygen-absorbing compounds. 3a,4,5,6,7,7a-hexahydro-4,7-methano-1H-indenol, represented by formula (1), 3a,4,5,6,7,7a-hexahydro-4,7-methano-1H-indenamine, represented by formula (1-b), and 3a,4,5,6,7,7a-hexahydro-4,7-methano-1H-inden-1-ol, represented by formula (1-c), are examples of oxygen-absorbing compounds having one unsaturated five-membered ring, one organic group 1, and one organic group 1 having a hydroxyl group or an amino group as a functional group with active hydrogen. [ka] [ka] [ka]

[0056] The oxygen-absorbing compound represented by formula (2) is, for example, a hydroxyl group, which is a functional group having active hydrogen on organic group 1 of the oxygen-absorbing compound represented by formula (1), and an isocyanate compound R, which is the origin of organic group 2. 1 (NCO) a The isocyanate group reacts with the hydroxyl group Active hydrogen is substituted, and a number of unsaturated five-membered rings and organic group 1 become R 1 Obtained by joining via It is an oxygen-absorbing compound that can do that. [ka] (In the formula, a is a number greater than or equal to 1, R 1 is a carbon atom with 1 or more carbon atoms. The functional base includes at least an alkylene and / or phenylene structure, and may further include structures derived from one or more selected from the group consisting of polyhydric alcohols, polyolefin polyols, polyether polyols, polyester polyols, polycarbonate polyols, poly(meth)acrylic acid ester polyols, phenoxy resins, and urethane chain extension polyols thereof.

[0057] The oxygen-absorbing compound shown in formula (5) is one in which a=2 in formula (2), and R 1 However, for example, the isocyanate compound OCN-R 4 -NCO and the hydroxyl group-containing compound HO-R 5 Oxygen absorption in the case of a group derived from -OH and containing a structural part produced by the reaction of the two. It is a sex compound. [ka] (In the formula, f is a number greater than or equal to 0, R 4 and R 5Each of these is an organic group having one or more carbon atoms, and is an organic group containing at least an alkylene and / or phenylene structure. Furthermore, it may include structures derived from one or more selected from the group consisting of polyhydric alcohols, polyolefin polyols, polyether polyols, polyester polyols, polycarbonate polyols, poly(meth)acrylic acid ester polyols, phenoxy resins, and urethane chain extension polyols thereof.

[0058] The oxygen-absorbing compound shown in formula (3) is, for example, R in formula (2). 1 Isosia This is an oxygen-absorbing compound derived from a nate compound and a hydroxyl group-containing compound, containing a structural part formed by the reaction of the two, and in which case the excess hydroxyl groups remain or are included due to chemical modification. [ka] (In the formula, each of b and c is a number greater than or equal to 1, R 2 is the number of carbon atoms The structure may include one or more organic groups, comprising at least an alkylene and / or phenylene structure, and further comprising one or more structures selected from the group consisting of polyhydric alcohols, polyolefin polyols, polyether polyols, polyester polyols, polycarbonate polyols, poly(meth)acrylic acid ester polyols, phenoxy resins, and urethane chain extension polyols thereof.

[0059] The oxygen-absorbing compound shown in formula (4) is, for example, R in formula (2). 1 Isosia This is an oxygen-absorbing compound derived from a nate compound and a hydroxyl group-containing compound, containing a structural part formed by the reaction of the two, and containing an excess of isocyanate groups either as residues or through chemical modification. [ka] (In the formula, each of d and e is a number greater than or equal to 1, R 3 is the number of carbon atoms The structure may include one or more organic groups, comprising at least an alkylene and / or phenylene structure, and further comprising one or more structures selected from the group consisting of polyhydric alcohols, polyolefin polyols, polyether polyols, polyester polyols, polycarbonate polyols, poly(meth)acrylic acid ester polyols, phenoxy resins, and urethane chain extension polyols thereof.

[0060] [Oxidation-promoting catalyst] An oxidation-promoting catalyst is a compound that accelerates the oxidation process by which oxygen-absorbing compounds absorb oxygen molecules. Examples of oxidation-promoting catalysts include peroxides and compounds containing cations composed of transition metals. Specific examples of such peroxides include hydrogen peroxide. A preferred compound containing a cation made of a transition metal is a metal soap consisting of a transition metal-containing compound capable of releasing a cation or complex of a transition metal atom and an anion or ligand made of a fatty acid. Preferred transition metals include cobalt, manganese, iron, nickel, and copper, while preferred anions or ligands include stearic acid, naphthenic acid, octic acid, acetylacetonate, and the like. As an oxidation-promoting catalyst, a metal soap can be used, formed by combining a cation consisting of one or more transition metals selected from the group consisting of the above-mentioned transition metals, and an anion consisting of one or more fatty acids selected from the group consisting of the above-mentioned long-chain fatty acids. Specific compounds include cobalt octylate, cobalt(II) acetylacetone, cobalt(III) acetylacetone, manganese(III) acetylacetone, iron(III) acetylacetone, and the like.

[0061] [Denaturant] The modifying agent is a compound having a functional group that reacts with the oxygen-absorbing compound when the oxygen-absorbing compound has a functional group, and various reactive monomers and resins can be used. By including a modifying agent in the oxygen-absorbing adhesive composition, it is possible to bond oxygen-absorbing compounds to other components in the oxygen-absorbing adhesive composition, adjust the content of oxygen-absorbing compounds in the oxygen-absorbing adhesive composition, or adjust the hardness of the cured product of the oxygen-absorbing adhesive composition.

[0062] For example, if the oxygen-absorbing compound has a hydroxyl group or an isocyanate group, a modifier consisting of an isocyanate compound and / or a hydroxyl group-containing compound can be used. When the oxygen-absorbing adhesive composition is urethane-based, the equivalent ratio NCO / OH of the oxygen-absorbing adhesive composition is preferably 0.5 or more and 8 or less. If it is smaller than the above range, the curing of the oxygen-absorbing adhesive composition may be insufficient, and sufficient laminate strength (adhesive strength) may not be obtained. If it is larger than the above range, the pot life of the oxygen-absorbing adhesive composition may become too short.

[0063] (Isocyanate compounds used as denaturants) The isocyanate compounds used as modifiers can be those used in the synthesis of oxygen-absorbing compounds, and any of aromatic isocyanates, aliphatic isocyanates, and urethane chain extension isocyanates thereof can be used. Furthermore, for the oxygen-absorbing adhesive composition to cure, it is preferable to use compounds having two or more isocyanate groups per molecule. However, isocyanate compounds having one isocyanate group per molecule can also be used in combination, as long as they do not hinder the sufficient effect of the oxygen-absorbing adhesive composition. Among isocyanate compounds having two or more isocyanate groups in one molecule, the biuret form of hexamethylene diisocyanate is particularly preferred.

[0064] Specific isocyanate compounds include tetramethylene diisocyanate, hexamethylene diisocyanate, lysine diisocyanate, isophorone diisocyanate, norbornane diisocyanate, xylene diisocyanate, toluene diisocyanate, diphenylmethane diisocyanate, hydrogenated diphenylmethane diisocyanate, phenylene diisocyanate, diphenyl ether diisocyanate, polymethylene polyphenyl polyisocyanate, and their trimethylolpropane adducts, biuret compounds, allophanates, isocyanurates (trimers), and various derivatives thereof. Among these, biuret compounds of toluene diisocyanate, isophorone diisocyanate, and hexamethylene diisocyanate are preferred.

[0065] (Hydroxyl group-containing compounds for use as denaturants) The hydroxyl group-containing compound used as a modifier can be the same hydroxyl group-containing compound used in the synthesis of the oxygen-absorbing compound, and any of aromatic hydroxyl group-containing compounds, aliphatic hydroxyl group-containing compounds, and urethane chain extension polyols thereof can be used. Furthermore, for the oxygen-absorbing adhesive composition to cure, it is preferable to use a compound having two or more hydroxyl groups per molecule. However, a hydroxyl group-containing compound having one hydroxyl group per molecule can also be used in combination, as long as it does not hinder the sufficient effect of the oxygen-absorbing adhesive composition. As hydroxyl group-containing compounds having two or more hydroxyl groups in one molecule, either aromatic hydroxyl group-containing compounds or aliphatic hydroxyl group-containing compounds can be used, and they may be alcohol-based or phenol-based. Among isocyanate compounds having two or more isocyanate groups in one molecule, polyalkylene ether diols and urethane chain-extended polyols of polyalkylene ether diols are particularly preferred.

[0066] [Diluting solvent] The diluent is not particularly limited as long as it uniformly dissolves or disperses the oxygen-absorbing compound and the oxidation-promoting catalyst, resulting in a uniform oxygen-absorbing adhesive composition suitable for the dry lamination process. Examples of diluents include ester-based diluents, ketone-based diluents, and hydrocarbon-based diluents. Examples of ester-based diluents include ethyl acetate and butyl acetate; examples of ketone-based diluents include methyl ethyl ketone; and examples of hydrocarbon-based diluents include toluene. Among these, ethyl acetate is easy to use and therefore preferred.

[0067] [Various additives] The oxygen-absorbing adhesive composition may contain various additives as needed. For example, curing accelerators, curing modifiers to extend pot life, antioxidants to suppress the decrease in oxygen absorption during storage, use, and before the contents are placed in the packaging of oxygen-absorbing adhesive compositions, adhesion aids, tackifiers, leveling agents, UV absorbers, defoamers, and colorants. Pigments and extender pigments can also be added.

[0068] (Curing accelerator) As a curing accelerator, any agent that promotes the curing reaction of the oxygen-absorbing adhesive composition can be used without particular limitations. Specific curing accelerators include metal-containing compounds such as dibutyltin dilaurate, dibutyltin diacetate, dioctyltin dilaurate, dibutyltin dimalate, tetrabutyl titanate, and tetraisopropyl titanate, as well as tertiary amines such as 1,8-diazabicyclo(5,4,0)undecene-7, 1,5-diazabicyclo(4,3,0)nonene-5, and triethanolamine. One or more compounds selected from this group can be used.

[0069] (Hardening modifier) In cases where the pot life of an oxygen-absorbing adhesive composition is shortened due to the oxidation-promoting catalyst it contains, the pot life can be extended by using a curing modifier in combination. As specific curing modifiers, phosphoric acids are preferred, for example, orthophosphoric acid, metaphosphoric acid, polyphosphoric acid, and their ester derivatives, and one or more selected from the group consisting of these can be used. The amount of reaction modifier added is preferably 200 ppm or more and 400 ppm or less relative to the resin component of the oxygen-absorbing adhesive composition. If the amount is less than the above range, it will be difficult to obtain the effect of extending the pot life, and if it is more than the above range, there is a risk of inhibiting the curing of the oxygen-absorbing adhesive composition.

[0070] (Antioxidant) To suppress the deterioration of oxygen absorption during storage and use of the oxygen-absorbing adhesive composition, and even before the packaging made using the oxygen-absorbing adhesive composition contains its contents, and to maintain high oxygen absorption after the contents are contained, the oxygen-absorbing adhesive composition may contain an antioxidant. Specific antioxidants include phenols, lactones, thioethers, gallic acids, ascorbic acid, erythorbic acid, catechins, dibutylhydroxytoluene, tocopherol, citric acid, butylhydroxyanisole, phosphite esters, hindered amines, and aromatic amines. One or more of these can be selected from the group and used. Furthermore, if heat or light is intended to be used as a trigger for oxygen absorption, it is preferable to use antioxidants with low heat and light resistance, such as ascorbic acid and tocopherol, and it is not preferable to use antioxidants with high heat and light resistance, such as phenolic compounds. The amount of antioxidant added is preferably 10 ppm or more and 10,000 ppm or less relative to the oxygen-absorbing compound. If the amount is less than the above range, the antioxidant effect is likely to be insufficient, and if it is more than the above range, there is a risk that the oxygen absorption will decrease.

[0071] (Adhesive enhancer) As an adhesive aid to enhance adhesion, a silane coupling agent is preferred. Examples of silane coupling agents include γ-glycidoxypropyltrialkoxysilane, γ-methacryloxypropyltrialkoxysilane, γ-glycidoxypropylmethyldialkoxysilane, β-(3,4-epoxycyclohexyl)ethyltrialkoxysilane, γ-aminopropyltrialkoxysilane, γ-aminopropylmethyldialkoxysilane, N-(β-aminoethyl)-γ-aminopropyltrialkoxysilane, N-(β-aminoethyl)-γ-aminopropylmethyldialkoxysilane, N-butyl-3-amino-2-methylpropyltrialkoxysilane, γ-mercaptopropyltrialkoxysilane, and γ-mercaptopropylmethyldialkoxysilane, which have alkoxy groups Preferably, the group is a methoxy group or an ethoxy group, and one or more selected from the group consisting of these can be used.

[0072] (Adhesion agent) Examples of tackifiers include paraffin wax, polyethylene wax, rosin, rosin glycerin ester, terpenes, and alkylphenols, and one or more selected from this group can be used.

[0073] (Leveling agent) Examples of leveling agents include acrylic polymer-based, modified silicone-based, and acetylenediol-based agents, and one or more selected from this group can be used.

[0074] (UV absorber) Examples of UV absorbers include benzotriazole-based, hydroxyphenyltriazine-based, and hindered amine-based agents, and one or more selected from this group can be used.

[0075] (Antifoaming agent) Examples of defoaming agents include surfactants and polyether-modified silicone oils, and one or more selected from this group can be used.

[0076] (Coloring pigments) Examples of coloring pigments include organic pigments such as anthraquinone, diketopyrrolopyrrole, perylene maroon, carbon black, dioxazine, perylene, benzimidazolon, isoindolinone, isoindoline, phthalocyanines, and indanthrene, as well as inorganic pigments such as yellow iron oxide, red iron oxide, azomethine copper complex, titanium dioxide, and silicon dioxide. One or more pigments selected from this group can be used.

[0077] (Extender pigments) Extender pigments are white or colorless pigments used as bulking agents or as modifiers for coloring power, gloss, strength, and feel. Specific examples include inorganic pigments such as barium sulfate, barium carbonate, calcium carbonate, magnesium oxide, magnesium carbonate, magnesium hydroxide, barium titanate, calcium hydroxide, calcium sulfite, calcium sulfate, calcium oxide, calcium silicate, titanium dioxide, silica, zeolite, and talc. One or more of these pigments can be selected from the group and used.

[0078] Method for preparing oxygen-absorbing adhesive compositions Oxygen-absorbing adhesive compositions can be manufactured by mixing all their components, including an oxygen-absorbing compound, an oxidation-promoting catalyst, and optionally, a modifier, a diluent, and various additives. Alternatively, they can be manufactured by mixing an oxygen-absorbing compound, an oxidation-promoting catalyst, and optionally, a modifier, a diluent, and various additives, into an existing adhesive composition. The method of mixing as described above, and the order in which each component is mixed, are not particularly limited, and the methods and mixing sequences used to prepare general adhesive compositions can be applied. Specific mixing methods include dissolving in a solvent and mixing, or melt-kneading. In this case, it is preferable to adjust the heating temperature to improve solubility and dispersibility.

[0079] Method of using oxygen-absorbing adhesive compositions There are no particular limitations on how the oxygen-absorbing adhesive composition can be used; general adhesive usage methods can be applied. Examples include the non-solvent lamination method, which involves heating the material to achieve the appropriate viscosity, and the dry lamination method, which involves adding a diluent solvent or other adhesive formulations to adjust the coating viscosity to the appropriate level. When forming an adhesive layer using an oxygen-absorbing adhesive composition, the application amount is 2-5 g / m². 2 Preferably, 3-5 g / m 2 This is preferable. If the amount is less than the above range, sufficient oxygen absorption may not be obtained, and if it is more than the above range, the oxygen absorption will not change much and will lead to a cost disadvantage, so it is undesirable.

[0080] Laminates obtained by forming an adhesive layer using an oxygen-absorbing adhesive composition are usually subjected to aging at a temperature of 20°C or higher and 50°C or lower for 2 to 5 days. Furthermore, when aging, it is preferable to perform the aging process at the lowest possible temperature or in an inert gas atmosphere in order to avoid reducing the oxygen absorption capacity of the laminate. When storing the fabricated laminate, it is preferable to store it at 10°C or below, or under an inert gas atmosphere, in order to avoid reducing the oxygen absorption capacity of the laminate.

[0081] Regarding objects that can be bonded: There are no particular limitations on the objects to which the oxygen-absorbing adhesive composition can be bonded; for example, it can be bonded to resin molded products, resin films, paper, metals, metal foils, inorganic vapor-deposited film surfaces, and inorganic oxide vapor-deposited film surfaces.

[0082] Specific examples of resins used in resin films include polyester resins such as polyethylene terephthalate (PET), polyamide resins such as various types of nylon, polyethylene resins, polypropylene resins, cyclic polyolefin resins, polystyrene resins, polyolefin resins such as acrylonitrile-styrene copolymer (AS resin), acrylonitrile-butadiene-styrene copolymer (ABS resin), and polybutene resins, polyvinyl chloride resins, polycarbonate resins, polyimide resins, polyamide-imide resins, diallyl phthalate resins, silicone resins, polysulfone resins, polyphenylene sulfide resins, polyethersulfone resins, polyurethane resins, cellulose resins, poly(meth)acrylic resins, polyvinylidene chloride resins, acetal resins, and fluorine resins.

[0083] Specific examples of paper include, for instance, high-size bleached or unbleached paper substrates for paper layers, or paper substrates such as pure white roll paper, kraft paper, cardboard, coated paper, processed paper, milk paper, and others. Examples of metal foils include aluminum foil, copper foil, and stainless steel foil. Aluminum is a specific example of a metal used in an inorganic vapor-deposited layer. Specific examples of inorganic oxides for the inorganic vapor deposition layer include silica, alumina, indium tin oxide, zinc oxide, tin oxide, titanium oxide, zirconium oxide, vanadium oxide, barium oxide, chromium oxide, silicon nitride, silicon carbide, etc. Among these, silica and alumina are preferred.

[0084] ≪Sealant layer≫ The sealant layer may consist of a single layer, or it may be a multilayer structure of two or more layers with the same or different compositions. Since the sealant layer is a layer used to heat-seal oxygen-absorbing laminates together when forming oxygen-absorbing paper containers for liquids, it is preferable that it contains a resin with heat-sealing properties.

[0085] Furthermore, the sealant layer may contain any additives, as long as they do not significantly impair the effects of the present invention. Examples of additives include various resin additives commonly used to adjust the moldability, productivity, and various physical properties of resin films, such as antiblocking agents, slip agents, antioxidants, pigments, flow control agents, flame retardants, fillers, ultraviolet absorbers, and surfactants. The thickness of the sealant layer is preferably 25 μm or more and 150 μm or less, and more preferably 40 μm or more and 70 μm or less.

[0086] (Heat-sealable resin) As heat-sealable resins, polyolefin resins, acid-modified polyolefin resins obtained by graft polymerization or copolymerization using unsaturated carboxylic acids or their anhydrides such as acrylic acid, methacrylic acid, maleic acid, maleic anhydride, fumaric acid, and itaconic acid, polyvinyl acetate resins, poly(meth)acrylic resins, polyvinyl chloride resins, and other resins can be used. These resins can be used individually or in combination. Among the resins mentioned above, polyolefin resins offer advantages in terms of adhesion and manufacturing cost, etc. From this viewpoint, low-density polyethylene and linear low-density polyethylene are particularly preferred among polyolefin resins.

[0087] For polyolefin resins with heat-sealing properties and acid-modified polyolefin resins, it is preferable to use plant-derived polyolefin resins as raw materials. However, polyolefin resins derived from fossil fuels may also be included. By using plant-derived polyolefin resins, the environmental impact can be reduced. Plant-derived resins can be selected with appropriate densities and MFRs depending on the physical properties of the fossil fuel-derived resin used in combination and the usage conditions of the laminate. The content of plant-derived polyolefin resin in the sealant layer is preferably 40% by mass or more and 100% by mass or less. If it is lower than the above range, the effect of reducing environmental impact will be reduced. When the sealant layer has a multilayer structure, the sealant layer may include layers containing plant-derived polyolefin resin and layers that do not contain plant-derived polyolefin resin. For example, it is preferable that the outer surface layer, which is the outermost surface of the laminate, does not contain plant-derived polyolefin resin. Furthermore, when the sealant layer has a multilayer structure of three or more layers, it is preferable that the layers on both surfaces of the sealant layer do not contain plant-derived polyolefin resin, while the inner layers do contain plant-derived polyolefin resin.

[0088] (Polyolefin resin) Specific examples of polyolefin resins include polyethylene, low-density polyethylene, medium-density polyethylene, high-density polyethylene, linear low-density polyethylene, ethylene-α·olefin copolymer polymerized using a metallocene catalyst, polypropylene, ethylene-vinyl acetate copolymer, ethylene-vinyl alcohol copolymer, ionomer resin, ethylene-acrylic acid copolymer, ethylene-ethyl acrylate copolymer, ethylene-methacrylic acid copolymer, ethylene-methyl methacrylate copolymer, ethylene-propylene copolymer, methylpentene(co)polymer, butene(co)polymer, ethylene-acrylic acid copolymer, ethylene-methacrylic acid copolymer, and cyclic olefin(co)polymers such as polynorvonene. The copolymer may be random or block copolymer. Polyolefin resins are classified into, for example, polyethylene resins and polypropylene resins, depending on the monomer skeleton used in the synthesis of the polyolefin, and may also be copolymers. In the present invention, the term "polyolefin resin" is used as a general term for various types, and for example, various polyolefin resins are used. The term polyethylene resin is also used as a general term for ethylene. Polyolefins produced by polymerization using α-olefins such as ethylene, propene, 1-butene, 1,3-butadiene, and 1-hexene as raw materials are called polyethylene resins, polypropylene resins, polybutylene resins, polybutadiene resins, polyhexene resins, etc. For polymerization methods, for example, high-pressure polymerization is common for low-density polyethylene, while for linear low-density polyethylene, low-pressure polymerization (gas-phase polymerization using Ziegler-Natta catalysts or liquid-phase polymerization using metallocene catalysts), slurry polymerization, solution polymerization, and gas-phase polymerization are common.

[0089] Furthermore, polyolefin resins are classified into fossil fuel-derived polyolefin resins and plant-derived polyolefin resins, depending on the origin of their raw material monomers. (Fossil fuel-derived polyolefin resin) In the present invention, the fossil fuel-derived polyolefin resin is a polyolefin resin that does not use plant-derived raw material monomers, but instead uses raw material monomers obtained by thermally decomposing naphtha obtained from fossil fuels, as in the conventional method. (Plant-derived polyolefin resin) In this invention, "plant-derived" means that the product contains carbon derived from plant materials, and for example, it means that the product is manufactured using compounds obtained from plants as raw materials. One method for producing plant-derived polyolefin resins involves, for example, first fermenting sugar solutions or starches obtained from plants such as sugarcane, corn, and sweet potatoes using microorganisms such as yeast, according to conventional methods, to produce bioethanol. This bioethanol is then heated in the presence of a catalyst to obtain ethylene and α-olefins (1-butene, 1-hexene, etc.) through intramolecular dehydration reactions. Next, these can be used as raw material monomers for polymerization, and plant-derived polyolefin resins can be produced by polymerization in the presence of a conventional catalyst, similar to the production of fossil fuel-derived polyolefin resins. The catalyst and polymerization method used are the same as those for fossil fuel-derived polyolefin resins. Some of the monomers used as raw materials for polymerization, as well as the monomers used in copolymerization, can be derived from fossil fuels, if necessary.

[0090] (Method for forming a sealant layer) The method for forming the sealant layer is not particularly limited, and conventionally known methods for laminating sealant layers can be applied. A sealant film consisting of one or more layers for the sealant layer may be prepared in advance, and the sealant film may be bonded to other layers constituting the laminate via an adhesive or the like to form the laminate. As for the method of preparing the sealant film, one or more resin compositions may be melt-extruded and formed into a film by the inflation method, or melt-extruded and narrowed on a roll by an extrusion method using T-die molding or the like to form a film. In this case, it is preferable to corona-treat one side of the prepared sealant film and then bond and laminate it with the corona-treated side facing the side to be laminated. Alternatively, a resin composition for forming a sealant layer may be melted, melt-extruded (co) and poured onto the layer to be laminated, and a single or multi-layer sealant layer may be laminated on top of the other layers constituting the laminate by an extrusion method using a feed block method or a T-die molding method using a multi-manifold method. In either method, a multilayer sealant film can be produced by co-melt extrusion using resin compositions of the same or different compositions.

[0091] ≪Paper base layer≫ As the material for the paper substrate layer, for example, a general known and publicly available paper substrate with excellent mechanical, physical, chemical, and other properties, particularly supportive properties, can be used as the basic material for the paper substrate layer of a liquid paper container. The paper substrate layer may consist of a single layer, or it may consist of two or more layers laminated by any lamination means of the same or different compositions. The paper substrate layer may further include a resin layer. The resin layer may be formed by coating or extruding a resin or resin composition, or by laminating a resin film. For example, the water resistance of the paper substrate layer can be improved by providing a coating resin layer, for example, 2 μm or more and 50 μm or less, on the surface of the paper substrate layer.

[0092] Specific examples of resins include polyester resins such as polyethylene terephthalate (PET) and polyethylene naphthalate, polyolefin resins such as polyethylene resins and polypropylene resins, polyamide resins such as nylon, polyaramid resins, polycarbonate resins, polyacetal resins, fluororesins, and other tough thermoplastic resins. When forming the coating resin layer by extrusion, it is preferable to use a polyethylene-based resin, and in particular, it is preferable to use LDPE. Furthermore, the resin film produced from the above-mentioned resin can be an unstretched film or a stretched film that has been stretched in one or two axes. Among the above, biaxially oriented PET film and biaxially oriented polypropylene film are preferably used. Furthermore, to improve moisture resistance and adhesion to other layers, multilayer resin films can be used, which are made by laminating the above-mentioned resin film with polyvinylidene chloride (PVDC) coating, or by laminating polyethylene, polypropylene, cyclic olefin copolymer, fluororesin, etc. Furthermore, in order to improve adhesion with adjacent layers, the surface of the resin layer may be subjected to physical surface treatments such as corona discharge treatment, ozone treatment, plasma treatment, glow discharge treatment, or sandblasting, or to chemical surface treatments such as chemical treatment using chemicals or oxidation treatment, as needed.

[0093] (Paper base material) The paper substrate can be given shapeability, flexibility, rigidity, etc. For example, a highly sizing bleached or unbleached paper substrate for paper layers, or a paper substrate such as pure white roll paper, kraft paper, cardboard, coated paper, processed paper, milk paper, barrier coated paper, etc. can be used. The basis weight of the paper substrate is 100 g / m². 2 More than 500g / m 2 The following is preferable: 120 g / m 2 More than 400g / m 2 The following is more preferable: By setting the basis weight of the paper substrate within the above numerical range. This allows for improving the strength of paper containers manufactured using the laminate while maintaining the ease of processing the laminate. The paper substrate layer may be made by laminating multiple layers of these papers together.

[0094] Furthermore, in order to improve adhesion with adjacent layers, the surface of the paper substrate may be subjected to physical surface treatments such as corona discharge treatment, ozone treatment, plasma treatment, glow discharge treatment, and sandblasting, or to chemical surface treatments such as chemical treatment using chemicals and oxidation treatment, as needed. Specific chemicals used in chemical treatment include oxidized starch, hydroxyethyl etherified starch, enzyme-modified starch, polyacrylamide, polyvinyl alcohol, surface sizing agents, water-resistant agents, water-retaining agents, thickeners, and lubricants, which can be used individually or in combination of two or more types. The above-mentioned chemicals can be used in combination with pigments. Pigments include kaolin, clay, engineered kaolin, delaminated clay, Inorganic pigments such as heavy calcium carbonate, light calcium carbonate, mica, talc, titanium dioxide, barium sulfate, calcium sulfate, zinc oxide, silicic acid, silicates, colloidal silica, and satin white, as well as organic pigments such as dense, hollow, or core-shell types, can be used individually or in combination of two or more types. The surface treatment method for the paper substrate is not particularly limited, but known coating equipment such as rod metering size presses, pound-type size presses, gate roll coaters, spray coaters, blade coaters, and curtain coaters can be used. The method of manufacturing the base paper (papermaking) is not particularly limited, and paper substrates can be manufactured by papermaking using known methods such as acidic papermaking, neutral papermaking, and alkaline papermaking, using known halftone formers, on-top hybrid formers, gap former machines, etc.

[0095] The base paper is made from pulp and may contain fillers, various additives, etc. As pulp, chemical pulps such as bleached hardwood kraft pulp (LBKP), unbleached hardwood kraft pulp (LUKP), bleached softwood kraft pulp (NBKP), unbleached softwood pulp (NUKP), and sulfite pulp can be used; mechanical pulps such as stone-ground pulp and thermomechanical pulp; wood fibers such as deinked pulp and recycled paper pulp; and non-wood fibers obtained from kenaf, bamboo, hemp, etc. One type may be used alone, or two or more types may be mixed as appropriate. Among these, it is preferable to use chemical pulp or mechanical pulp made from wood fibers, and more preferable to use chemical pulp, because it contains fewer foreign matter, undergoes less discoloration over time, has high whiteness, and provides a good surface texture when printed. Any known filler can be used. Specific examples include white carbon, talc, kaolin, clay, heavy calcium carbonate, light calcium carbonate, titanium dioxide, zeolite, and synthetic resin fillers. Various additives can be used as needed, including aluminum sulfate, various anionic, cationic, nonionic, or amphoteric yield enhancers, water drainage enhancers, paper strength enhancers, and internal sizing agents for papermaking. Furthermore, dyes, fluorescent whitening agents, pH adjusters, defoamers, pitch control agents, slime control agents, etc., can also be added as needed.

[0096] The paper substrate and resin used in the paper substrate layer may, as needed, be modified or improved in terms of processability, heat resistance, weather resistance, mechanical properties, dimensional stability, oxidation resistance, slipperiness, release properties, flame retardancy, mold resistance, electrical properties, strength, etc., by adding plastic compounding agents and additives such as lubricants, crosslinking agents, antioxidants, ultraviolet absorbers, light stabilizers, fillers, reinforcing agents, antistatic agents, and pigments. The amount of these additives can be arbitrarily added according to the purpose, as long as it does not adversely affect other properties.

[0097] ≪Printing layer≫ The printed layer visually displays design patterns such as letters, numbers, figures, symbols, pictures, and patterns for purposes such as decoration, indicating contents, expiration dates, manufacturer and seller information, and adding aesthetic appeal, and can form desired design patterns. The printed layer can be applied to the surface of the paper substrate layer that forms the outside of the liquid paper container using conventionally known printing inks. The printing method is not particularly limited, and conventionally known methods such as gravure printing, flexographic printing, and screen printing can be used. The printed layer may be applied to the entire surface to be printed, or to only a part of it. To allow the printed layer to be visible, it is preferable that the printed layer be the outermost layer, or that the layer outside the printed layer be transparent, when forming the liquid paper container.

[0098] ≪Adhesive resin layer≫ Each layer constituting the oxygen-absorbing laminate includes an adhesive resin layer and an anchor coat layer. It is possible. The adhesive resin layer may be, for example, a layer formed by a (co)extrusion lamination method or a T-die (co)extrusion method in which an adhesive resin composition is melt-extruded (extruded resin layer), or a layer formed by dry lamination using a dry laminate adhesive (dry laminate layer). In the present invention, among the above, the extruded resin layer is preferred. If necessary, the surface of the laminated adhesive resin layer may be subjected to physical surface treatments such as corona discharge treatment, ozone treatment, plasma treatment, glow discharge treatment, or sandblasting, or to chemical surface treatments such as oxidation treatment using chemicals. Examples of resins that can be contained in the above-mentioned adhesive resin composition include polyolefin resins, acid-modified polyolefin resins obtained by graft polymerization or copolymerization of polyolefin resins using unsaturated carboxylic acids or their anhydrides such as acrylic acid, methacrylic acid, maleic acid, maleic anhydride, fumaric acid, and itaconic acid, polyvinyl acetate resins, poly(meth)acrylic resins, polyvinyl chloride resins, and other resins. These resins can be used individually or in combination.

[0099] Specific examples of polyolefin resins include polyethylene, low-density polyethylene, medium-density polyethylene, high-density polyethylene, linear low-density polyethylene, ethylene-α·olefin copolymer polymerized using a metallocene catalyst, polypropylene, ethylene-vinyl acetate copolymer, ethylene-vinyl alcohol copolymer, ionomer resin, ethylene-acrylic acid copolymer, ethylene-ethyl acrylate copolymer, ethylene-methacrylic acid copolymer, ethylene-methyl methacrylate copolymer, ethylene-propylene copolymer, methylpentene(co)polymer, butene(co)polymer, polyisoprene, ethylene-acrylic acid copolymer, ethylene-methacrylic acid copolymer, polynorvonene, and other cyclic olefin(co)polymers. The copolymer may be random or block copolymer. Polyolefin resins are classified into, for example, polyethylene resins and polypropylene resins, depending on the monomer skeleton used in the synthesis of the polyolefin, and may also be copolymers. In this invention, the term "polyolefin resin" is added as a general term for various types, and for example, polyethylene resin is also used as a general term for various types of polyethylene. Polyolefins produced by polymerization using α-olefins such as ethylene, propene, 1-butene, 1,3-butadiene, and 1-hexene as raw materials are called polyethylene resins, polypropylene resins, polybutylene resins, polybutadiene resins, polyhexene resins, etc.

[0100] The adhesive resin layer may contain additives such as antioxidants, ultraviolet absorbers, light stabilizers, antistatic agents, antiblocking agents, flame retardants, crosslinking agents, and colorants, to the extent that they do not impair the properties of the present invention. The thickness of the adhesive resin layer is not particularly limited, but in the case of extruded resin, it is preferably 5 μm or more and 60 μm or less, and in the case of dry laminate adhesive, 0.1 g / m 2 More than 20g / m 2 The following is preferable. By setting the thickness of the adhesive resin layer within the above numerical range, stable adhesive strength can be achieved. Furthermore, as the adhesive for dry lamination that constitutes the adhesive resin layer formed by dry lamination, specific examples of adhesives that can be used include two-component curing urethane adhesives, polyester urethane adhesives, polyether urethane adhesives, acrylic adhesives, polyester adhesives, polyamide adhesives, polyvinyl acetate adhesives, epoxy adhesives, rubber adhesives, and others.

[0101] The anchor coat layer is a layer formed by applying and drying an anchor coat agent, and it can improve the adhesion between adjacent layers. Examples of anchor coating agents include any resin with a heat resistance temperature of 135°C or higher, such as vinyl-modified resins, epoxy resins, urethane resins, polyester resins, polyethyleneimines, and the like. Among the above, a curable anchor coating agent is particularly preferred, which contains a polyacrylic or polymethacrylic resin (polyol) having two or more hydroxyl groups in one molecule as the main component, and an isocyanate compound as the curing agent. Furthermore, a silane coupling agent may be used in combination, and nitrated cotton may be used in combination to improve heat resistance. The thickness of the anchor coat layer is not particularly limited, but is preferably, for example, 0.05 μm or more and 1 μm or less.

[0102] Functional Layer Examples of functional layers include layers made of resin that have barrier properties against oxygen gas, water vapor, etc., and / or low adsorption of fragrance components, etc., contained in the contents to be filled and packaged, and are rich in fragrance retention, and further have the property of not causing changes in taste or off-odor, and are extrudeable, or layers made of light-shielding material (light-shielding layer).

[0103] Specifically, the above-mentioned resins can include, for example, polyacrylic resins, polymethacrylic resins, polyacrylonitrile resins, polymethacrylonitrile resins, polystyrene resins, polycarbonate resins, polyethylene terephthalate resins or resins obtained by copolymerizing or modifying a portion of their ethylene and / or terephthalate components with other di- or higher polyhydric alcohol components or dicarboxylic acid components, or polyester resins such as polyethylene naphthalate resins, polyamide resins, saponified ethylene-vinyl acetate copolymers, polyvinyl alcohol resins, polyvinyl chloride resins, polyvinylidene chloride resins, and other resins.

[0104] Among the resins mentioned above, it is preferable to use a resin that has fragrance retention properties as well as barrier properties against oxygen gas or water vapor. Specifically, it is preferable to use a resin that is rich in fragrance retention and barrier properties, such as a saponified ethylene-vinyl acetate copolymer, a polyamide resin, a polyacrylonitrile resin, or a polyester resin.

[0105] The light-shielding layer is a layer provided to prevent ultraviolet light and / or visible light from reaching the contents. The light-shielding layer can be formed using white ink mainly composed of titanium dioxide, black ink mainly composed of carbon black, gray ink mainly composed of aluminum paste, a colored resin film with pigments or dyes added to provide light shielding, metal foil, a metal vapor-deposited film, etc. Furthermore, as mentioned above, when using metal foil such as aluminum foil as the barrier layer, the barrier layer can also serve as a light-shielding layer. These light-blocking materials can be used individually or in combination of two or more types. The thickness of the light-shielding layer is preferably 4 μm or more and 12 μm or less, and more preferably 5 μm or more and 9 μm or less, when using white ink, black ink, or gray ink. For aluminum foil, a thickness of 5 μm to 30 μm is preferred; for metal vapor-deposited films, a thickness of 50 Å to 3000 Å is preferred, and 100 Å to 1000 Å is more preferred; and for colorant-colored resin films, a thickness of 5 μm to 300 μm is preferred, and 10 μm to 100 μm is more preferred.

[0106] ≪Reinforcement Layer≫ The reinforcing layer is a layer that provides the laminate with mechanical strength, deformation resistance, drop impact resistance, pinhole resistance, heat resistance, sealing properties, quality preservation, workability, hygiene, and other properties. The reinforcing layer may be formed from any of the following: an extruded or inflated resin film, a resin coating film, synthetic paper, etc.

[0107] Specifically, the resin contained in the reinforcing layer can be any known resin, such as low-density polyethylene, medium-density polyethylene, high-density polyethylene, linear low-density polyethylene, polypropylene, ethylene-propylene copolymer, ethylene-vinyl acetate copolymer, ionomer resin, ethylene-ethyl acrylate copolymer, ethylene-acrylic acid or methacrylic acid copolymer, methylpentene polymer, polybutene resin, polyvinyl chloride resin, polyvinyl acetate resin, polyvinylidene chloride resin, vinyl chloride-vinylidene chloride copolymer, poly(meth)acrylic resin, polyacrylonitrile resin, polystyrene resin, acrylonitrile-styrene copolymer (AS resin), acrylonitrile-butadiene-styrene copolymer (ABS resin), polyester resin, polyamide resin, polycarbonate resin, polyvinyl alcohol resin, saponified ethylene-vinyl acetate copolymer, fluorine resin, diene resin, polyacetal resin, polyurethane resin, cellulose, nitrocellulose, and others. In the present invention, it is preferable to use a polyester resin for the reinforcing layer. Examples of polyester resins include polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polybutylene terephthalate (PBT), polybutylene naphthalate (PBN), polytetramethylene terephthalate, and polycyclohexanedimethylene terephthalate (PCT). Furthermore, the above-mentioned resin film can be used in any form, such as unstretched, or stretched in a uniaxial or biaxial direction. The reinforcing layer may have a vapor-deposited film for the purpose of improving barrier properties, and may also contain additives such as antioxidants, ultraviolet absorbers, light stabilizers, antistatic agents, antiblocking agents, flame retardants, crosslinking agents, and colorants, to the extent that they do not impair the properties of the present invention. There are no particular restrictions on the thickness of the reinforcing layer, but it is preferably 5 μm or more and 500 μm or less, and more preferably 10 μm or more and 200 μm or less.

[0108] <Regarding the method for manufacturing oxygen-absorbing laminates for paper containers> A method for manufacturing an oxygen-absorbing laminate for paper containers using the materials described above will be explained. The manufacturing method shown below is just one example and does not limit the present invention. The lamination of each layer constituting the oxygen-absorbing laminate for paper containers can be carried out using any lamination method used when manufacturing ordinary packaging materials, such as wet lamination, dry lamination, solvent-free dry lamination, extrusion lamination, T-die co-extrusion molding, co-extrusion lamination, inflation lamination, and others. The oxygen-absorbing laminate for paper containers of the present invention can also be subjected to secondary processing for the purpose of imparting chemical functions, electrical functions, magnetic functions, mechanical functions, friction / abrasion / lubrication functions, optical functions, thermal functions, biocompatibility, and other surface functions. Examples of secondary processing include embossing, painting, bonding, printing, metallizing (plating, etc.), machining, surface treatment (antistatic treatment, corona discharge treatment, plasma treatment, photochromism treatment, physical vapor deposition, chemical vapor deposition, coating, etc.). Furthermore, the laminate of the present invention can be subjected to lamination (dry lamination or extrusion lamination), bag making, and other post-processing.

[0109] Furthermore, when performing the above lamination, if necessary, pretreatments such as corona treatment or ozone treatment can be applied to the surface of each layer. In addition, anchor coating agents such as isocyanate-based (urethane-based), polyethyleneimine-based, polybutadiene-based, organotitanium-based, or laminating adhesives such as polyurethane-based, polyacrylic-based, polyester-based, epoxy-based, polyvinyl acetate-based, cellulose-based, etc. can be optionally used. It can be used.

[0110] As long as the paper substrate layer, oxygen barrier layer, oxygen-absorbing adhesive layer, and sealant layer are laminated in this order, the formation and lamination order of each layer can be arbitrary. For example, let's consider the case of manufacturing an oxygen-absorbing laminate for paper containers having a layer structure consisting of a paper substrate layer, an oxygen barrier layer, an oxygen-absorbing adhesive layer, and a sealant layer. For example, first, an oxygen barrier layer is formed on the corona-treated surface of the paper substrate layer. Next, an oxygen-absorbing adhesive composition is applied to the laminated oxygen barrier layer and dried as necessary to form an oxygen-absorbing adhesive layer. Then, a sealant film for the sealant layer is bonded onto the oxygen-absorbing adhesive layer to form the sealant layer. Then, perform aging treatment as needed. In this way, an oxygen-absorbing laminate for paper containers can be obtained.

[0111] <Oxygen-absorbing packaging material for paper containers> Oxygen-absorbing packaging material for paper containers is a packaging material made from an oxygen-absorbing laminate for paper containers and used in the production of liquid paper containers. The oxygen-absorbing packaging material for paper containers may further include layers having various functions, as needed.

[0112] <Oxygen-absorbing paper container for liquids> The oxygen-absorbing paper container for liquids of the present invention is a paper container for liquids made using the oxygen-absorbing packaging material for paper containers of the present invention. Furthermore, added value can be provided through various shapes, designs, and printed decorations. In one embodiment, the oxygen-absorbing paper container for liquids of the present invention has the shape shown in Figure 3, and the paper container 20 of the present invention comprises a body portion 21, a roof-shaped top portion 22 with an inclined upper surface formed at the open end above the body portion 20, and a bottom portion 23 formed at the open end below the body portion 21. The paper container 20 can also be manufactured, for example, from a blank plate 24 shown in Figure 4. In oxygen-absorbing paper containers for liquids, the oxygen barrier layer is located outside the oxygen-absorbing adhesive layer.

[0113] <Method for manufacturing oxygen-absorbing paper containers for liquids> The paper container 20 can be formed, for example, by the following method. The examples listed below are merely examples of methods for manufacturing the oxygen-absorbing paper container for liquids of the present invention, and the present invention is not limited thereto. First, the laminate shown in Figure 2 is punched out to form a blank plate 24 as shown in Figure 4. Next, the paper container 20 can be manufactured by attaching the spout component that matches the cap, folding it so that the sealant layer is on the inside, heat sealing it, and then attaching the cap. In the above, the heat sealing method can be a known method such as a bar seal, rotary roll seal, belt seal, impulse seal, high-frequency seal, ultrasonic seal, or flame seal.

[0114] The present invention will be described in more detail below with reference to examples and comparative examples. [Examples]

[0115] The present invention will be described in more detail by the following examples and comparative examples, but the present invention is not limited to these examples.

[0116] <Raw materials> The main raw materials used in the examples are as follows: [Raw materials for oxygen-absorbing compounds] • Polypropylene ether diol 1: Manufactured by Sanyo Chemical Industries, Ltd., SANNIX PP-1000. Number average molecular weight 1000. • Polypropylene ether diol 2: Manufactured by Sanyo Chemical Industries, Ltd., SANNIX PK-400. Number average molecular weight 400. • Hydroxyl-terminated polyisoprene 1: Manufactured by Idemitsu Kosan Co., Ltd., Poly ip. Number average molecular weight 2500. • Hydroxyl-terminated polybutadiene 1: Manufactured by Idemitsu Kosan Co., Ltd., Poly bd R15HT. Number average molecular weight 1200. A hydroxyl-terminated 1,2 addition polymer of 1,3-butadiene. • Toluene diisocyanate 1: Manufactured by Tosoh Corporation, Coronate T-65. • Oxygen-absorbing compound 1: 3a,4,5,6,7,7a-hexahydro-4,7-methano-1H-inden-6-ol. • Oxidation-promoting catalyst solution 1: Octop AE, manufactured by Hope Pharmaceutical Co., Ltd. A 4% ethyl acetate solution of cobalt octylate, which is an oxidation-promoting catalyst. • Oxidation-promoting catalyst solution 2: Acetope Mn(III), manufactured by Hope Pharmaceutical Co., Ltd. A 10% ethyl acetate solution of acetylacetone manganese(III), an oxidation-promoting catalyst.

[0117] [Adhesive resin layer, coating resin layer, anchor coating agent] • DL Adhesive 1: Two-component curing polyester urethane adhesive manufactured by Rock Paint Co., Ltd. • LDPE 1: LDPE manufactured by Nippon Polyethylene Co., Ltd., Novatec LC520. Density 0.923 g / cm³ 3 MFR 3.6g / 10 minutes. AC agent 1: Urethane-based anchor coating agent. [Films for paper substrate layers, reinforcing layers, and barrier layers] • PET film 1: Biaxially oriented PET film, E5200, manufactured by Toyobo Co., Ltd. 12 μm thick. • Transparent vapor-deposited PET film 1: IB-PET manufactured by Dai Nippon Printing Co., Ltd. One-sided transparent alumina vapor-deposited PET film. 12 μm thick. ·Paper base material 1: basis weight 400g / m 2 Clearwater Paper Company's uncoated base paper. • Aluminum foil 1:7μm thick.

[0118] [Ink for printing layers] • Gravure Ink 1: SNP, manufactured by Showa Ink Industry Co., Ltd.

[0119] [Film for sealant layer] • LLDPE film 1: SK-L manufactured by Dai Nippon Printing Co., Ltd. Unstretched LLDPE film Hmm. 40 μm thick.

[0120] <Preparation of raw material solutions> (Synthesis of polyol 1 and preparation of polyol solution 1) The following raw materials were added to a flask equipped with a nitrogen inlet tube, stirrer, rectification column, and condenser, and dehydration condensation was carried out at an internal temperature of 180-200°C while stirring. Ethylene glycol 53.8 parts by mass Neopentyl glycol 180.3 parts by mass 1,6-Hexanediol 204.6 parts by mass Isophthalic acid 287.8 parts by mass Adipic acid 273.5 parts by mass When the acid value of the solids in the reaction solution reached 15 mg KOH / g, the dehydration reaction was further carried out at 200-240°C while blowing in nitrogen. When the acid value of the solid content of the reaction solution fell below 10 mg KOH / g, the internal pressure was reduced to 30 Torr and the reaction continued. When the acid value of the solid content of the reaction solution fell below 3 mg KOH / g, the reaction was terminated, and the mixture was cooled to room temperature to obtain polyol 1. The number-average molecular weight of the obtained polyester polyol, polyol 1, was 2000. Next, polyol 1 was dissolved in ethyl acetate to prepare a solution with a solid content of 60% by mass, thereby obtaining polyol solution 1.

[0121] (Synthesis of polyol 2 and preparation of polyol solution 2) The following raw materials were placed in a flask equipped with a nitrogen inlet tube, a stirrer, and a condenser, and the mixture was heated while stirring, followed by a reflux reaction for 6 hours. Polypropylene ether diol 1 300.0 parts by mass Polypropylene ether diol 2 250.0 parts by mass Toluene diisocyanate 1 104.0 parts by mass 163.5 parts by mass of ethyl acetate After confirming that the absorption of the isocyanate group had completely disappeared using infrared absorption spectroscopy, the synthesis was terminated, and the mixture was cooled to obtain polyol 2. The number-average molecular weight of the obtained urethane chain-extended polyol, polyol 2, was 2000. Next, polyol 2 was dissolved in ethyl acetate to prepare a solution with a solid content of 60% by mass, obtaining polyol solution 2.

[0122] (Preparation of polyisocyanate solution 1) The following raw materials were added to a flask equipped with a nitrogen inlet tube, a stirrer, and a condenser, and stirred to obtain polyisocyanate solution 1 with a solid content of 60% by mass. 100.0 parts by mass of a burette body of hexamethylene diisocyanate 66.7 parts by mass of ethyl acetate

[0123] [Table 1]

[0124] (Synthesis of oxygen-absorbing compound and preparation of oxygen-absorbing compound solution) [Oxygen-absorbing compound 2] First, the following raw materials were added to a flask equipped with a nitrogen inlet tube, a stirrer, and a condenser, and reacted at an internal temperature of 80 to 90 °C for 8 hours while stirring. 100.0 parts by mass of oxygen-absorbing compound 1 74.0 parts by mass of isophorone diisocyanate Synthesis was terminated after confirming that the absorption of isocyanate groups had completely disappeared in the infrared absorption spectrum, and it was cooled to obtain oxygen-absorbing compound 2. Then, oxygen-absorbing compound 2 was dissolved in ethyl acetate to prepare oxygen-absorbing compound solution 2 with a solid content of 80% by mass.

[0125] [Oxygen-absorbing compound 3] First, the following raw materials were added to a flask equipped with a nitrogen inlet tube, a stirrer, and a condenser, and reacted at an internal temperature of 80 to 90 °C for 8 hours while stirring. 100.0 parts by mass of oxygen-absorbing compound 1 212.5 parts by mass of polyisocyanate solution 1 Synthesis was terminated after confirming that the content of NCO groups in the solid content of the reaction solution had reached approximately 0.64% by mass by the amine equivalent method, and it was cooled and the solvent was removed to obtain oxygen-absorbing compound 3. Then, oxygen-absorbing compound 3 was dissolved in ethyl acetate to prepare an oxygen-absorbing compound solution 3 with a solid content of 60% by mass.

[0126] [Oxygen-absorbing compound 4] First, the following raw materials were added to a flask equipped with a nitrogen inlet tube, a stirrer, and a condenser, and the reaction was carried out for 8 hours at an internal temperature of 80-90°C while stirring. Oxygen-absorbing compound 1: 100.0 parts by mass Polyol solution 1 682.3 parts by mass Polyisocyanate solution 1 265.6 parts by mass After confirming that the absorption of the isocyanate group had completely disappeared using infrared absorption spectroscopy, the synthesis was terminated, and the solvent was removed to obtain oxygen-absorbing compound 4. Then, oxygen-absorbing compound 4 was dissolved in ethyl acetate to prepare an oxygen-absorbing compound solution 4 with a solid content of 60% by mass.

[0127] [Oxygen-absorbing compound 5] Except for using polyol solution 2 instead of polyol solution 1, the oxygen-absorbing compound 5 was obtained by the same procedure as for oxygen-absorbing compound 4 described above. Then, oxygen-absorbing compound 5 was dissolved in ethyl acetate to prepare an oxygen-absorbing compound solution 5 with a solid content of 60% by mass.

[0128] [Oxygen-absorbing compound 6] The following raw materials were placed in a flask equipped with a nitrogen inlet tube, a stirrer, and a condenser, and the reaction was carried out for 6 hours at an internal temperature of 80-90°C while stirring. Hydroxyl-terminated polyisoprene 1 100.0 parts by mass Isophorone diisocyanate 4.7 parts by mass After confirming that the absorption of the isocyanate group had completely disappeared using infrared absorption spectroscopy, the synthesis was terminated, and the mixture was cooled to obtain oxygen-absorbing compound 6, which is a urethane polyol. The number-average molecular weight of the obtained oxygen-absorbing compound 6 was 7000. Then, oxygen-absorbing compound 6 was dissolved in ethyl acetate to prepare an oxygen-absorbing compound solution 6 with a solid content of 60% by mass.

[0129] The charging compositions of the reaction solutions when synthesizing oxygen-absorbing compounds 2 to 6 were summarized in Table 2. Also, the charging compositions of oxygen-absorbing compound solutions 2 to 6 were summarized in Table 3.

[0130]

Table 2

[0131]

Table 3

[0132] <Preparation of Oxygen-Absorbing Adhesive Composition> (Preparation of Oxygen-Absorbing Adhesive Composition A1) The following raw materials were mixed and homogenized at room temperature to obtain oxygen-absorbing adhesive composition A1, and various evaluations were carried out. Oxygen-absorbing compound solution 2 100 parts by mass Polyol solution 1 100 parts by mass Polyisocyanate solution 1 10 parts by mass Oxidation-promoting catalyst solution 1 1 part by mass Ethyl acetate 140 parts by mass

[0133] (Preparation of Oxygen-Absorbing Adhesive Compositions A2 to A9, B1 to B2) According to the formulations in Tables 4 and 5, the same operations as for oxygen-absorbing adhesive composition A1 were carried out to obtain oxygen-absorbing adhesive compositions A2 to A9, B1 to B2.

[0134]

Table 4

[0135]

Table 5

[0136] [Table 6]

[0137] [Example 1] On one side of the PET film 1 used as a reinforcing layer, oxygen-absorbing adhesive A1 was applied after drying at a rate of 3.0 g / m². 2 Apply and dry so that it becomes an oxygen barrier layer, and aluminum foil 1 and dryer It was bonded together using the bonding method. Then, AC agent 1 was applied to the surface of the bonded aluminum foil 1 so that the film thickness after drying was 0.5 μm, and dried to form an anchor coat layer. Next, the anchor coat layer and the paper substrate were bonded together by extrusion lamination via an adhesive resin layer made of 330°C molten LDPE1 extruded from an extrusion molding machine. The thickness of the adhesive resin layer was adjusted to 25 μm. Then, the surface of the laminated paper substrate 1 was extruded with molten LDPE 1 extruded from an extrusion molding machine at 330°C to form a 25 μm thick coating resin layer. Next, AC agent 1 was applied to the surface of the laminated PET film 1 so that the film thickness after drying was 0.5 μm, and then dried to form an anchor coat layer. Then, the anchor coat layer surface and the LLDPE film 1 for the sealant layer were bonded together by extrusion lamination via an adhesive resin layer made of molten LDPE 1 at 330°C, which was extruded from the molding machine. The thickness of the adhesive resin layer was adjusted to 25 μm. Next, the surface of the coated resin layer formed above was subjected to corona treatment, and a printed layer was formed using gravure ink 1 to obtain an oxygen-absorbing laminate for paper containers. Various evaluations were then performed. Layer composition: Printed layer / Coating resin layer (25 μm) / Paper substrate layer (365 g / m²) 2 ) / adhesive resin layer (25μm) / Anchor coat layer (0.5μm) / Oxygen barrier layer (aluminum foil 1:7μm) / Oxygen-absorbing adhesive layer (3g / m 2 ) / Reinforcement layer (12μm) / Anchor coat layer ( 0.5μm) / Adhesive resin layer (25μm) / Sealant layer (40μm)

[0138] [Examples 2-9, Comparative Examples 1-3] In accordance with Table 7, an oxygen-absorbing laminate for paper containers was obtained and evaluated in the same manner as in Example 1, except that the oxygen-absorbing adhesive composition A1 of Example 1 was replaced with one of the oxygen-absorbing adhesive compositions A2 to A9, B1, B2, or DL ​​adhesive 1.

[0139] [Example 10] An oxygen-absorbing laminate for paper containers was obtained and evaluated in the same manner as in Example 1, except that the aluminum foil 1 for the oxygen barrier layer was replaced with a transparent vapor-deposited PET film 1, and the vapor-deposited surface was used on the oxygen-absorbing adhesive 1 side. Layer composition: Printed layer / Coating resin layer (25 μm) / Paper substrate layer (365 g / m²) 2 ) / adhesive resin layer (25μm) / Anchor coat layer (0.5μm) / Oxygen barrier layer (PET film: 12μm / deposition layer) / Oxygen-absorbing adhesive layer (3g / m 2 ) / Reinforcement layer (12μm) / Anchor Coating layer (0.5 μm) / Adhesive resin layer (25 μm) / Sealant layer (40 μm)

[0140] [Comparative Example 4] A laminate was obtained and evaluated in the same manner as in Example 10, except that oxygen-absorbing adhesive 1 was replaced with DL adhesive 1.

[0141] [Table 7]

[0142] <Summary of Results> All embodiments of the oxygen-absorbing laminates for paper containers and oxygen-absorbing paper containers for liquids exhibit excellent lamination. It demonstrated a balance between strength, oxygen absorption, and low odor. On the other hand, the comparative laminate and liquid paper container showed inferior results in either lamination strength, oxygen absorption, or low odor.

[0143] <Evaluation Method>

[0144] [Oxygen absorption] Using the obtained oxygen-absorbing laminate for paper containers, a 200 mL paper container was manufactured by forming a box with the sealant layer on the inside. The contents-holding section of the resulting container was purged with nitrogen and then sealed. 1400 cc / m² of the inner surface area of ​​the bag was added to the inside of the container using a syringe. 2 Air was injected into the container, the injection site was repaired with adhesive tape, and the contents were stored in a 25°C constant temperature bath for 14 days. The air in the container was then sampled with a syringe, the oxygen concentration was measured, and the amount of oxygen absorbed was calculated. The oxygen concentration was measured using a zirconia-type oxygen meter (manufactured by Toray Industries, Inc.).

[0145] [Lamination strength] Strip-shaped test pieces with a width of 15 mm were prepared from the obtained oxygen-absorbing laminate for paper containers, and the lamination strength between the layers via the oxygen-absorbing adhesive layer was measured using a tensile testing machine at a tensile speed of 50 mm / min.

[0146] <Odor> The odor inside the pouch was detected by smelling it after measuring the oxygen absorption rate, and the odor was assessed according to the following criteria. Odors originating from the sealant layer were excluded from the assessment. Evaluation criteria: 0: Odorless 1: Faint odor 2: Weak odor 3: Moderate odor 4: Strong odor [Explanation of Symbols]

[0147] 1: Oxygen-absorbing laminate for paper containers 2:Paper base layer 3: Oxygen barrier layer 4: Oxygen-absorbing adhesive layer 5: Sealant layer 6: Printing layer 7: Coating resin layer 8: Adhesive resin layer 9: Anchor coat layer 10: Reinforcement layer 20: Oxygen-absorbing paper container for liquids 21: Torso 22:Top 23: Bottom 24: Blank plate

Claims

1. An oxygen-absorbing laminate for paper containers, for manufacturing a liquid paper container, comprising a layer structure in which at least a paper substrate layer, an oxygen barrier layer, an oxygen-absorbing adhesive layer, and a sealant layer are laminated in this order, The oxygen-absorbing adhesive layer is a layer formed from an oxygen-absorbing adhesive composition. The oxygen-absorbing adhesive composition contains at least an oxygen-absorbing compound and an oxidation-promoting catalyst. The oxygen-absorbing compound has one or more unsaturated five-membered rings at the ends of the main chain of the molecule, or at the ends of both the main chain and side chains of the molecule, and does not have an N-hydroxyimide group. Any of the bonds between the five carbon atoms constituting the unsaturated five-membered ring is a carbon-carbon double bond. The unsaturated five-membered ring is bonded to a monovalent and / or divalent or more electron-donating organic group 1, If there is one unsaturated five-membered ring, the five-membered ring or the organic group 1 has a functional group having an active hydrogen, or a group in which the active hydrogen of a functional group having an active hydrogen is substituted with a monovalent organic group 2. If there are two or more unsaturated five-membered rings, the unsaturated five-membered rings are linked to each other via a divalent or higher organic group 2 that substitutes for the active hydrogen of the active hydrogen group on each of the five-membered rings or the organic group 1. Oxygen-absorbing laminate for paper containers.

2. Between the oxygen-absorbing adhesive layer and the sealant layer, there is further a reinforcing layer. An oxygen-absorbing laminate for paper containers according to claim 1.

3. The aforementioned paper substrate layer includes a coating resin layer on its surface. An oxygen-absorbing laminate for paper containers according to claim 1 or 2.

4. The structure of the unsaturated five-membered ring, or the structure consisting of the unsaturated five-membered ring and organic group 1, is derived from one or more selected from the group consisting of cyclopentadiene, dicyclopentadiene, norbornene, and derivatives thereof. An oxygen-absorbing laminate for paper containers according to any one of claims 1 to 3.

5. The organic group 2 includes a structural component derived from an isocyanate compound, or an isocyanate compound and a hydroxyl group-containing compound. An oxygen-absorbing laminate for paper containers according to any one of claims 1 to 4.

6. The isocyanate compound is one or more selected from the group consisting of xylene diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, toluene diisocyanate, diphenylmethane diisocyanate, and derivatives thereof. An oxygen-absorbing laminate for paper containers according to claim 5.

7. The hydroxyl group-containing compound is one or more selected from the group consisting of polyhydric alcohols, polyolefin polyols, polyether polyols, polyester polyols, polycarbonate polyols, poly(meth)acrylic acid ester polyols, phenoxy resins, and urethane chain elongated polyols thereof. An oxygen-absorbing laminate for paper containers according to claim 5 or 6.

8. The aforementioned organic group 2 does not have a crosslinking functional group. An oxygen-absorbing laminate for paper containers according to any one of claims 1 to 7.

9. The organic group 2 has one or more crosslinkable functional groups, The crosslinkable functional group is a hydroxyl group and / or an isocyanate group. An oxygen-absorbing laminate for paper containers according to any one of claims 1 to 7.

10. The oxygen-absorbing compound contains one or more compounds selected from the group consisting of compounds represented by the following formulas (1) to (4): The number-average molecular weight of the oxygen-absorbing compound is 100 to 10000. The concentration of the unsaturated five-membered ring in the oxygen-absorbing compound is 5% by mass or more and 60% by mass or less. An oxygen-absorbing laminate for paper containers according to any one of claims 1 to 7. 【Chemistry 1】 【Chemistry 2】 【Transformation 3】 【Chemistry 4】 (In the formula, a to e are each numbers greater than or equal to 1, R 1 , R 2 , R 3 Each of these is an organic group having one or more carbon atoms, and includes at least an alkylene and / or phenylene structure, and may further include structures derived from one or more selected from the group consisting of polyhydric alcohols, polyolefin polyols, polyether polyols, polyester polyols, polycarbonate polyols, poly(meth)acrylic acid ester polyols, phenoxy resins, and urethane chain extension polyols thereof.

11. The oxygen-absorbing compound contains the compound represented by the following formula (5), The number-average molecular weight of the oxygen-absorbing compound is 300 to 10000. The concentration of the unsaturated five-membered ring in the oxygen-absorbing compound is 5% by mass or more and 60% by mass or less. An oxygen-absorbing laminate for paper containers according to any one of claims 1 to 7. 【Transformation 5】 (In the formula, f is a number greater than or equal to 0, R 4 and R 5 Each of these is an organic group having one or more carbon atoms, and is an organic group containing at least an alkylene and / or phenylene structure. Furthermore, it may include structures derived from one or more selected from the group consisting of polyhydric alcohols, polyolefin polyols, polyether polyols, polyester polyols, polycarbonate polyols, poly(meth)acrylic acid ester polyols, phenoxy resins, and urethane chain extension polyols thereof.

12. The oxidation-promoting catalyst is a compound containing a cation composed of a peroxide or a transition metal. An oxygen-absorbing laminate for paper containers according to any one of claims 1 to 11.

13. The compound containing the aforementioned transition metal cation is a metal soap comprising a transition metal compound capable of releasing a transition metal cation or complex and an anion or ligand made of a fatty acid. An oxygen-absorbing laminate for paper containers according to claim 12.

14. The oxygen-absorbing adhesive composition further contains a modifier, The modifying agent contains an isocyanate compound and / or a hydroxyl group-containing compound. An oxygen-absorbing laminate for paper containers according to any one of claims 1 to 13.

15. The isocyanate compound contained in the aforementioned denaturing agent is one or more selected from the group consisting of xylene diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, toluene diisocyanate, diphenylmethane diisocyanate, and derivatives thereof. An oxygen-absorbing laminate for paper containers according to claim 14.

16. The hydroxyl group-containing compound contained in the aforementioned modifying agent includes one or more selected from the group consisting of polyester polyols, poly(meth)acrylic acid ester polyols, polyalkylene ether diols, and urethane chain extension polyols thereof. An oxygen-absorbing laminate for paper containers according to claim 14 or 15.

17. An oxygen-absorbing packaging material for paper containers, manufactured using an oxygen-absorbing laminate for paper containers as described in any one of claims 1 to 16.

18. A liquid oxygen-absorbing paper container made using the oxygen-absorbing packaging material for paper containers described in claim 17, The oxygen barrier layer is a layer located outside the oxygen-absorbing adhesive layer. Oxygen-absorbing paper container for liquids.

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