JP5881349B2 - Deoxidant-containing coating film and laminate - Google Patents

Description

  The present invention includes an oxygen scavenger, an organic oxygen scavenger, an organic oxygen scavenger, a specific polyolefin resin, a hygroscopic material and / or a transition metal compound, an acidic compound, and an aqueous medium. The present invention relates to a deoxidant-containing coating film containing a specific polyolefin resin and a hygroscopic material and / or a transition metal compound, and further to a laminate in which this deoxidizer-containing coating film is laminated.

  It is indispensable to provide a deoxidizing function to packaging materials for food, medical / pharmaceuticals, and electrical / electronic parts. There are roughly two types of materials for providing oxygen scavenging functions: metal oxygen scavengers and organic oxygen scavengers, but metal oxygen scavengers react with metal detectors used for foreign object detection surveys. There is a problem.

There is no such problem with organic oxygen scavengers, and in particular, ascorbic acid is widely used as a main component of oxygen scavenging materials because of its nature of reducing oxygen.
There are various forms of using an organic oxygen scavenger as a component of the oxygen scavenging material, but in general, a method of using it by kneading it into a resin material (Patent Document 1) or an ascorbic acid segment in a polymer chain (Patent Document 2), a method of using a porous material impregnated with a solution containing an organic oxygen absorber (Patent Document 3), and impregnating a water absorbent resin with a solution containing an organic oxygen absorber (Patent Document 4), and a method (Patent Document 5) in which a solution containing ascorbic acid is placed on a support to coat the surface has also been proposed.

  However, the method (Patent Document 1) used by kneading into a resin material has an advantage that an oxygen scavenging layer can be laminated on a desired packaging substrate, but the organic oxygen scavenger is thermally decomposed during kneading. There is a concern to do. Further, since the adhesion of the deoxidized layer is poor, there is a problem that an adhesive layer needs to be interposed between the substrate and the base material.

  Moreover, although the method (patent document 2) which introduce | transduces an ascorbic acid segment into a polymer chain solves said problem, the complexity of introducing the ascorbic acid segment into a polymer chain is needed. In addition, there was a problem in terms of adhesion when the obtained polymer was directly laminated on a desired packaging substrate.

  The method of using a porous material impregnated with a solution containing an organic oxygen scavenger (Patent Document 3) has a problem that the use is limited because the base material is limited to the porous material. . Moreover, since the decomposition reaction of the organic oxygen scavenger accompanying the oxygen removal reaction proceeds promptly after production, there is a problem that the storage stability is poor.

  A method of using a solution containing an organic oxygen scavenger impregnated in a water-absorbent resin (Patent Document 4) is a method in which a necessary material is filled and sealed in a packaging material and used as an oxygen absorbent package. Since the water-absorbent resin, which is one of the constituent materials, is a gel in which a water-soluble resin is partially crosslinked to make it water-insoluble, it has poor adhesion to the substrate and is difficult to be laminated on the desired substrate. .

  And the method (patent document 5) which puts the solution containing ascorbic acid on a support body, and coat | covers the surface (patent document 5) places an ink-form thru | or cream-form oxygen absorber on the base material which has a hygroscopic property, and water | moisture content. This is a technique of covering with a covering material while maintaining the state of inclusion. Therefore, the base material is limited to those having hygroscopicity, and there is a problem that the surface must be further coated, and the decomposition reaction of the organic oxygen scavenger accompanying the deoxygenation reaction proceeds promptly after production. There was a problem of poor storage stability.

JP 2004-136479 A Japanese Patent Laid-Open No. 9-328521 JP-A-62-14939 JP-A-3-86238 JP-A-10-353

  The present invention solves the above-mentioned problems, and can be easily applied on a desired substrate, and the obtained coating film is deoxygenated on the substrate with good adhesion. It is intended to provide a coating agent, and to provide a deoxidant-containing coating film that is laminated with good adhesion on a desired substrate and has excellent storage stability. An object of the present invention is to provide a laminate in which a coating film containing an organic oxygen scavenger with good adhesion is laminated on a material.

  As a result of investigations to solve the above-mentioned problems, the present inventors have found that a deoxygenation coating containing an organic oxygen scavenger, a polyolefin resin having a specific composition, a hygroscopic material and / or a transition metal compound, an acidic compound, and an aqueous medium. The agent was found to be excellent in coating properties, and the resulting coating film was also excellent in deoxidation function and storage stability, and reached the present invention.

That is, the gist of the present invention is as follows .
[1 ] An oxygen scavenger characterized in that it is a coating film containing an organic oxygen scavenger, a polyolefin resin containing an olefinic hydrocarbon unit and a unit having an amino group, and a hygroscopic material and / or a transition metal compound. Contains paint film.
[ 2 ] The content of the unit having an amino group is 0.1 mol% or more and less than 10 mol% with respect to 100 mol% of all the structural units constituting the polyolefin resin [ 1 ] An oxygen scavenger-containing coating film .
[3 ] A laminate comprising the oxygen-absorbing agent-containing coating according to [ 1 ] or [2] laminated on a substrate.
[ 4 ] A laminate in which a sealant layer is laminated on the oxygen scavenger-containing coating film of the laminate according to [ 3 ] above.
[ 5 ] The laminate according to [ 3 ] or [ 4 ], wherein the substrate has a barrier property.
[ 6 ] The laminate according to any one of [ 3 ] to [ 5 ], wherein a moisture absorbing layer is laminated on at least one of the upper and lower sides of the oxygen scavenger-containing coating.

  The oxygen scavenger of the present invention contains an organic oxygen scavenger, a polyolefin resin having a specific composition, a hygroscopic material and / or a transition metal compound, an acidic compound, and an aqueous medium. It is possible to form a uniform coating film on various substrates, and it is excellent in workability. And since it is a water system, it is excellent also in environmental conservation.

  The deoxidant-containing coating film of the present invention has a deoxygenation function and is excellent in storage stability. For this reason, the laminated body of this invention can use a various material as a base material, is excellent in a deoxidation function, and can be preserve | saved for a long time in air | atmosphere. And by making a bag etc. of the laminated body of this invention, it becomes possible to use suitably as packaging materials, such as a foodstuff, a medical / medicine, an electrical / electronic component.

Hereinafter, the present invention will be described in detail.
The oxygen scavenger of the present invention (hereinafter sometimes abbreviated as “coating agent”) is an organic oxygen scavenger, a polyolefin resin having a specific composition (hereinafter sometimes referred to as polyolefin resin A), a hygroscopic material, and / or It includes a transition metal compound, an acidic compound and an aqueous medium. Specifically, the oxygen scavenging coating of the present invention is an aqueous coating in which a polyolefin resin having an amino group is dispersed in an aqueous medium, and an organic oxygen scavenger and an acidic compound are dissolved in the aqueous medium. is there. The hygroscopic material and the transition metal compound may be dispersed or dissolved in the aqueous medium.

  The oxygen scavenger-containing coating film of the present invention (hereinafter sometimes abbreviated as “coating film”) contains an organic oxygen scavenger, a polyolefin resin A, a hygroscopic material, and / or a transition metal compound. The oxygen scavenger-containing coating film of the present invention is preferably obtained by coating the oxygen scavenger coating composition of the present invention. That is, it is preferable to remove the acidic compound and the aqueous medium by applying the deoxygenation coating agent of the present invention, and drying after coating.

  Examples of the organic oxygen scavenger contained in the oxygen scavenger and oxygen scavenger-containing coating of the present invention include ascorbic acid, catechol, erythorbic acid, pyrogallol, hydroquinone, reducing sugars, and tannic acid. These may be used alone or in combination. Of these, ascorbic acid, catechol, pyrogallol, and tannic acid are preferable, and ascorbic acid is particularly preferable from the viewpoint of cost and effect.

  In addition, organic acid salts such as sodium ascorbate are known as general organic oxygen scavengers, but in the present invention, a stable oxygen scavenger cannot be obtained. Is preferably not used.

  The polyolefin resin A contained in the oxygen scavenger and oxygen scavenger-containing coating of the present invention contains olefinic hydrocarbon units and amino group-containing units as constituent components.

  As the olefinic hydrocarbon unit in the present invention, those having 2 to 6 carbon atoms are preferable, ethylene, propylene, 1-butene, isobutene, 1-pentene, 4-methyl-1-pentene, 3-methyl-1-pentene. Alkenes such as 1-hexene and dienes such as butadiene and isoprene, and may have a plurality of these units. Among these, ethylene, propylene, 1-butene, and isobutene are preferable, and ethylene and propylene are more preferable from the viewpoint of ease of production of the resin, ease of aqueous dispersion, and adhesion to various materials.

  The content of the olefinic hydrocarbon unit in the polyolefin resin A in the present invention is preferably 65 to 99.9 mol%, more preferably 70 to 99.9 mol%, and 80 to 99.8 mol%. More preferably, 85-99.7 mol% is especially preferable. When the content of the olefinic hydrocarbon unit is less than 65 mol%, the water resistance and solvent resistance of the coating film obtained from the coating tends to decrease. When the content exceeds 99.9 mol%, the polyolefin resin A It tends to be difficult to disperse in water.

On the other hand, the unit having an amino group is a component that forms a polyolefin resin, and refers to a unit having one or more amino groups in the unit. The amino group means a monovalent functional group obtained by removing hydrogen from ammonia or a primary or secondary amine. Specifically, —NH ₂ , —NHR, —NRR ′ (however, R, R ′ Means an alkyl group or a hydroxyalkyl group).

  And the polyolefin resin A is equipped with the capability to disperse | distribute in an aqueous medium by the unit which has this amino group. In the coating agent of the present invention, an acidic compound is used as will be described later, and an amino cation is generated by neutralizing part or all of the amino group in the polyolefin resin with this acidic compound. And the aggregation between the polyolefin resin particles in an aqueous medium can be prevented by the electrostatic repulsion between the produced amino cations. By preventing agglomeration, the deoxidizing coating composition of the present invention becomes a cationic aqueous coating composition in which the polyolefin resin is uniformly dispersed and is stable in the acidic region. Here, the aqueous coating material in which the polyolefin resin is uniformly dispersed is a portion where the solid content concentration is locally different from other portions such as precipitation, phase separation or skinning in the aqueous medium. The one that is not in the state.

  Aggregation between resin particles can be suppressed by utilizing the electrostatic repulsion between amino cations as described above. In the present invention, as long as the polyolefin resin to be used has a certain amount of units having amino groups in the structural units, aggregation of the resin can be basically suppressed. However, since the resin agglomeration largely depends on the resin structure, the resin agglomeration can be more effectively suppressed by devising the resin structure. In this regard, according to the study by the present inventors, it is more likely to increase the number of amino groups contained in the unit having an amino group, and to suppress the aggregation of the resin more effectively by increasing the number of the unit itself. I understood it. In this case, it was also found that the latter is more effective even if the total number of amino cations in the resin is the same. Although these reasons are not clear, it is effective to spread the amino group in the resin to suppress the aggregation of the resin, and the structure itself of the unit having an amino group has a low ratio of contributing to the aggregation suppressing effect. it is conceivable that. Therefore, in order to suppress the aggregation of the resin more effectively, it can be said that it is sufficient to adjust only the content of the unit having an amino group. Basically, the structure related to the number of amino groups contained in the unit is considered. You don't have to.

  The content of the unit having an amino group is preferably 0.1 mol% or more and less than 10 mol%, more preferably 0.1 mol% with respect to 100 mol% of all the structural units constituting the polyolefin resin A. More than mol% and less than 4 mol%. Furthermore, it is preferably 0.2 mol% or more and less than 3 mol%, particularly preferably 0.3 mol% or more and less than 2 mol%, most preferably 0.3 mol% or more and less than 1 mol%. is there. When the content of the amino group-containing unit is less than 0.1 mol%, it is difficult to disperse the polyolefin resin in water, which is not preferable. On the other hand, if it is 10 mol% or more, the storage stability after aqueous dispersion tends to decrease, and the adhesion, water resistance, and solvent resistance of the resin tend to decrease, which is not preferable. The content of the unit having an amino group can generally be measured by NMR analysis.

  The unit having an amino group preferably has a carbonyl group derived from an unsaturated carboxylic acid unit or an unsaturated carboxylic anhydride unit. This is because the polyolefin resin A in the present invention is produced by reacting an amino compound with a unit having a carboxyl group or a carboxylic anhydride group so that an amino group can be easily introduced without cost. Therefore, in the polyolefin resin A, when the amino group is introduced as described above in forming the unit having an amino group, the production cost of the polyolefin resin A can be suppressed as a result. Generally, when an amino compound is reacted with a unit having a carboxyl group or a carboxylic acid anhydride group, the carbonyl group remains as soon as the amino group is introduced. Therefore, the fact that the carbonyl group derived from the unsaturated carboxylic acid unit or the unsaturated carboxylic acid anhydride unit is present in the unit having an amino group is the most proof of the cost reduction in producing the polyolefin resin A. It can be said that this is a preferred embodiment.

  As the amino compound, a polyfunctional amino compound is preferably employed. The polyfunctional amino compound refers to an amino compound having a plurality of functional groups in the molecule, and refers to a compound in which at least one of the plurality of functional groups is an amino group. Examples of functional groups other than amino groups include hydroxyl groups and halogens, and also include compounds having two or more amino groups such as diamines. By using a polyfunctional amino compound, an amino group can be introduced more effectively.

Furthermore, in the present invention, from the viewpoint of dispersion stability of the coating material and the adhesiveness and heat resistance of the resin, the unit having an amino group is an N-substituted imide unit derived from an unsaturated carboxylic anhydride unit, The N-substituent preferably has a substituent represented by the following formula (1).
_{^{- (CH 2) n NR 1}} R 2 ··· (1)
(Wherein R ¹ and R ² are hydrogen or an alkyl group having 1 to 5 carbon atoms, and n is an integer of 1 to 5)
In the above formulas ^{(1), R 1, R} 2 is an alkyl group having 1 to 5 carbon atoms, preferably an alkyl group having 1 to 2 carbon atoms. Moreover, in formula, n is an integer of 1-5, Comprising: The integer of 2-4 is preferable and the integer of 2-3 is preferable.

  Examples of the substituent represented by the formula (1) include N, N-dimethylaminoethyl group, N, N-dimethylaminopropyl group, N, N-dimethylaminobutyl group, N, N-diethylaminoethyl group, N, N-diethylaminopropyl group, N, N-diethylaminobutyl group and the like can be mentioned. Of these, an N, N-dimethylaminopropyl group is preferable.

  Examples of the unsaturated carboxylic acid anhydride constituting the N-substituted imide unit derived from the unsaturated carboxylic acid anhydride unit include maleic anhydride, itaconic anhydride, and the like, and are easily copolymerized with the olefinic hydrocarbon unit. Maleic anhydride is preferred.

  Specific examples of the N-substituted imide unit derived from the unsaturated carboxylic anhydride unit include N, N-dimethylaminoethylmaleimide, N, N-dimethylaminopropylmaleimide, N, N-dimethylaminobutylmaleimide, N, N -Diethylaminoethylmaleimide, N, N-diethylaminopropylmaleimide, N, N-diethylaminobutylmaleimide and the like. Two or more of these may be copolymerized.

  And when content of the N-substituted imide unit derived from the unsaturated carboxylic anhydride unit in polyolefin resin A increases, the heat resistance improvement effect tends to increase, and when the content decreases, the heat resistance improvement effect. Tend to be lower. Although the detailed mechanism by which the heat resistance changes depending on the content of the N-substituted imide unit derived from the unsaturated carboxylic acid anhydride unit is unknown, the polyolefin resin A becomes rigid by having an imide ring structure in its main chain, It is assumed that heat resistance is imparted. Therefore, heat resistance is improved also in the coating film of the present invention.

  When the content of the N-substituted imide unit derived from the unsaturated carboxylic acid anhydride unit is less than 0.1 mol%, the heat resistance improvement effect tends to be insufficient, and the coating film or laminate of the present invention In rare cases, the environment and conditions in which the body can be used are limited. Further, it tends to be difficult to disperse the polyolefin resin A in water, which is not preferable. On the other hand, when the content of the N-substituted imide unit derived from the unsaturated carboxylic acid anhydride unit is 10 mol% or more, the storage stability after the aqueous dispersion is lowered, the resin adhesion, water resistance, The solvent property tends to decrease, which is not preferable.

In the present invention, the unit having an amino group other than the N-substituted imide unit derived from the unsaturated carboxylic anhydride unit and the substituent represented by the formula (1) as the N-substituent In addition, an N-substituted amide unit derived from an unsaturated carboxylic acid unit and a substituent represented by the formula (1) as the N-substituent, an alkyl ester unit derived from an unsaturated carboxylic acid unit, What has the substituent represented by Formula (1) as the alkyl group is mentioned.
Examples of the unsaturated carboxylic acid constituting the N-substituted amide unit derived from the unsaturated carboxylic acid unit include acrylic acid and methacrylic acid. Specific examples of N-substituted amide units derived from unsaturated carboxylic acid units include N, N-dimethylaminopropylacrylamide, N, N-diethylaminoethylacrylamide, N, N-dimethylaminopropylmethacrylamide, N, N-diethylamino. And propylmethacrylamide.
Examples of the unsaturated carboxylic acid constituting the alkyl ester unit derived from the unsaturated carboxylic acid unit include acrylic acid and methacrylic acid. Specific examples of the alkyl ester unit derived from the unsaturated carboxylic acid unit include N, N-dimethylaminopropyl acrylate, N, N-diethylaminoethyl acrylate, N, N-dimethylaminopropyl methacrylate, N, N-diethylaminopropyl methacrylate, and the like. Is mentioned.
Two or more of these may be copolymerized.

  The polyolefin resin A in the present invention contains an olefinic hydrocarbon unit and a unit having an amino group, and may contain other monomer units as necessary.

  Other monomer units include (meth) acrylic acid esters such as methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate; dimethyl maleate, diethyl maleate , Maleic esters such as dibutyl maleate; vinyl esters such as vinyl formate, vinyl acetate, vinyl propionate and vinyl alcohol obtained by saponifying vinyl esters with basic compounds, etc .; acrylic acid, methacrylic acid, maleic acid, anhydrous Examples thereof include unsaturated carboxylic acids such as maleic acid, itaconic acid and itaconic anhydride.

  Especially, it is preferable that the polyolefin resin A in this invention has a (meth) acrylic acid ester unit. By having this unit, the coating film of the present invention using the polyolefin resin A is further improved in adhesion to the substrate.

  The content of other monomer units is preferably 25 mol% or less, more preferably from 0.1 to 20 mol%, still more preferably from 1 to 15 mol%. When the content exceeds 25 mol%, the strength of the coating film of the present invention using the polyolefin resin A tends to be lowered, which is not preferable.

  As molecular weight of polyolefin resin A in this invention, it is preferable that it is 5000-500000 in a mass mean molecular weight, 10000-200000 is more preferable, 15000-100000 is further more preferable, 20000-80000 is especially preferable. When the weight average molecular weight is less than 5,000, the adhesiveness and solvent resistance of the coating film of the present invention using the polyolefin resin A tend to decrease. When the weight average molecular weight exceeds 500,000, the polyolefin resin A is water-based. There is a tendency that aqueous dispersion in a medium becomes difficult.

  However, since a polyolefin resin is generally poorly soluble in a solvent, it may be difficult to measure the molecular weight. In such a case, the melt flow rate value indicating the fluidity of the molten resin is used as a measure of the molecular weight.

  The melt flow rate value of polyolefin resin A in the present invention (according to JIS K7210: 1999) is preferably 0.1 to 2000 g / 10 minutes, more preferably 0.5 to 1000 g / 10 minutes. 1 to 500 g / 10 min is more preferable, and 2 to 200 g / 10 min is particularly preferable. When the melt flow rate value exceeds 2000 g / 10 min, the adhesiveness and solvent resistance of the coating film of the present invention using the polyolefin resin A tend to decrease, and when it is less than 0.1 g / 10 min Tends to make it difficult to disperse the polyolefin resin in the present invention in an aqueous medium.

  The polyolefin resin A in the present invention has excellent processing characteristics, softness characteristics, etc., but the most characteristic property is that it is excellent in water dispersibility, and is stable in the acidic region by the aqueous dispersion method described later. It can be made into a cationic aqueous dispersion. In addition, since the polyolefin resin A in the present invention has excellent water dispersibility, it is not necessary to chlorinate for the purpose of improving solubility and water dispersibility, and it is preferable not to halogenate from the viewpoint of environmental conservation. .

  The method for producing the polyolefin resin A in the present invention is not particularly limited. In the present invention, the unit having an amino group preferably has an N-substituted imide unit derived from an unsaturated carboxylic anhydride unit and a substituent represented by the above formula (1) as the N-substituent. . Taking this as an example, (A) an unsaturated carboxylic acid anhydride and a primary amine compound having a substituent represented by the formula (1) are subjected to an imidization reaction to derive from an unsaturated carboxylic acid anhydride unit. A method in which an N-substituted imide is prepared in advance and this is copolymerized with an olefinic hydrocarbon and, if necessary, other monomers. (B) N-substitution derived from a previously prepared unsaturated carboxylic anhydride unit. A method of grafting an imide onto a polyolefin resin or an olefin copolymer, (C) a copolymer having olefinic hydrocarbon units and unsaturated carboxylic anhydride units as constituent components, and a formula (1) Examples thereof include a method of imidizing a primary amine compound having a substituent.

  In particular, in the method (C), a copolymer having raw material olefinic hydrocarbon units and unsaturated carboxylic anhydride units as constituents is obtained as an olefin-carboxylic anhydride copolymer at a low price from the market. In addition, since the amino compound can be imidized without using a special apparatus, the polyolefin resin A can be easily produced as a result, which is preferable.

  Olefin hydrocarbon units and unsaturated carboxylic acid anhydrides constituting a copolymer having an olefinic hydrocarbon unit and an unsaturated carboxylic anhydride unit as constituent components (hereinafter abbreviated as an acid anhydride-containing copolymer). The kind and content of the product unit may be any material that satisfies the configuration of the polyolefin resin A obtained after the imidization reaction. The acid anhydride-containing copolymer may have a monomer unit other than the olefinic hydrocarbon unit and the unsaturated carboxylic acid anhydride unit.

  Examples of the unsaturated carboxylic acid anhydride unit constituting the acid anhydride-containing copolymer include maleic anhydride and itaconic anhydride, and are maleic anhydride because they are easily copolymerized with olefinic hydrocarbon units. Is preferred.

  The content of the unsaturated carboxylic anhydride unit in the acid anhydride-containing copolymer is preferably 0.1 mol% or more and less than 10 mol%, and more preferably 0.1 mol% or more and less than 7 mol%. Preferably, it is 0.1 mol% or more and less than 4 mol%, more preferably 0.2 mol% or more and less than 3 mol%, and particularly preferably 0.3 mol% or more, 2 mol% or more. It is less than mol%, most preferably 0.3 mol% or more and less than 1 mol%. When the content of the unsaturated carboxylic acid anhydride is less than 0.1 mol%, the effect of improving the heat resistance of the resulting polyolefin resin A becomes insufficient, and it is difficult to disperse the polyolefin resin A in water. Become. On the other hand, when the content of the unsaturated carboxylic acid anhydride is 10 mol% or more, the storage stability after aqueous dispersion decreases, or the adhesion, water resistance, and solvent resistance of the resulting polyolefin resin A decrease. Tend to.

  In addition, as monomer units (other monomer units) other than the olefinic hydrocarbon units and unsaturated carboxylic anhydride units constituting the acid anhydride-containing copolymer, methyl (meth) acrylate, (meth) acrylic acid (Meth) acrylic acid esters such as ethyl, propyl (meth) acrylate and butyl (meth) acrylate; maleic acid esters such as dimethyl maleate, diethyl maleate and dibutyl maleate; vinyl formate, vinyl acetate, vinyl propionate And vinyl alcohols obtained by saponifying vinyl esters with basic compounds, etc .; unsaturated carboxylic acids such as acrylic acid, methacrylic acid, maleic acid, and itaconic acid. Especially, it is preferable that the anhydride containing copolymer in this invention has a (meth) acrylic acid ester unit. By having this unit, the adhesiveness and adhesiveness to the base material to the coating film obtained when it is set as the aqueous dispersion of this invention improve more.

  The state of copolymerization of the acid anhydride-containing copolymer is not particularly limited, and examples thereof include random copolymerization, block copolymerization, and graft copolymerization (graft modification).

  Specific examples of the acid anhydride-containing copolymer include ethylene-maleic anhydride copolymer, propylene-maleic anhydride copolymer, ethylene-maleic anhydride graft copolymer, ethylene-methyl (meth) acrylate- Maleic anhydride terpolymer, ethylene- (meth) acrylic acid ethyl-maleic anhydride terpolymer, ethylene- (meth) acrylic acid propyl-maleic anhydride terpolymer, ethylene- (meth) Ethylene- (meth) acrylic ester-maleic anhydride terpolymers such as butyl acrylate-maleic anhydride terpolymer, propylene-maleic anhydride graft copolymer, propylene-butene-maleic anhydride graft Examples thereof include a copolymer and a propylene-butene-ethylene-maleic anhydride graft copolymer.

  Among these, since the adhesiveness to the base material of the coating film using polyolefin resin A obtained is further improved, ethylene- (meth) methyl acrylate-maleic anhydride terpolymer, ethylene- (meta ) Ethyl acrylate-maleic anhydride terpolymer, ethylene- (meth) acrylic acid propyl-maleic anhydride terpolymer, ethylene- (meth) acrylate butyl-maleic anhydride terpolymer, etc. An ethylene- (meth) acrylic ester-maleic anhydride terpolymer is preferred.

  These acid anhydride-containing copolymers are available from Arkema “Bondyne”, “Rotada”, “Olevac”, Nippon Polyethylene “Lex Pearl ET”, “Adtex”, NOF “MODIPA”, Sanyo Chemical It can be widely obtained from the market as “Umex” manufactured by the company, “Admer” manufactured by Mitsui Chemicals, and “Auroren” manufactured by Nippon Paper Chemicals.

In the method (C) as described above, the polyolefin resin A is obtained by imidizing the acid anhydride-containing copolymer and an amino compound represented by the following formula (2).
^{_{H 2 N- (CH 2) n}} NR 1 R 2 (2)
(Wherein R ¹ and R ² are alkyl groups having 1 to 5 carbon atoms, and n is an integer of 1 to 5)
^Wherein, R 1, ^{R 2} is an alkyl group having 1 to 5 carbon atoms, preferably an alkyl group having 1 to 2 carbon atoms. When the number of carbon atoms is 6 or more, the boiling point of the amino compound becomes high, and unreacted substances easily remain in the resulting polyolefin resin, resulting in a decrease in water resistance. When either or both of R ¹ and R ² are hydrogen, both amino groups in the amino compound molecule react with the carboxylic acid anhydride during the imidation reaction, resulting in olefins. The copolymer forms a crosslinked structure, making aqueous dispersion difficult.
Moreover, in formula, n is an integer of 1-5, Comprising: The integer of 2-4 is preferable and the integer of 2-3 is preferable. When n is 0, there is a risk of explosion during handling. When n is 6 or more, the boiling point of the amino compound is high, and unreacted substances are likely to remain in the resulting polyolefin resin, resulting in water resistance. descend.

  As described above, the amino compound represented by formula (2) (hereinafter abbreviated as amino compound) is a diamine having a primary amine and a tertiary amine in the molecule. It is possible to generate an N-substituted unsaturated carboxylic imide having a dialkylaminoalkyl group as a substituent by imide bonding of a primary amine in the molecule with a carboxylic acid anhydride of an acid anhydride-containing copolymer. Become.

  Examples of the amino compound represented by the formula (2) include N, N-dialkylaminoalkylamine, among which N, N-dimethylaminoethylamine, N, N-dimethylaminopropylamine, N, N-dimethylaminobutylamine. N, N-diethylaminoethylamine, N, N-diethylaminopropylamine, N, N-diethylaminobutylamine and the like are preferable.

  In addition, when an acid anhydride-containing copolymer as described above and an amino compound are subjected to an imidization reaction, a known apparatus and method can be used. Examples thereof include a method of heating and stirring the acid anhydride-containing copolymer and the amino compound in a reaction vessel, and a method of heating and stirring continuously with an extruder.

  The oxygen scavenger and oxygen scavenger-containing coating of the present invention contain a hygroscopic material and / or a transition metal compound in addition to the organic oxygen scavenger as described above and the polyolefin resin of the present invention.

  The hygroscopic material contained in the oxygen scavenger and oxygen scavenger coating film of the present invention means a material that can adsorb and retain moisture. This hygroscopic material acts as an activator for the deoxygenation reaction. Specific examples of the hygroscopic material include activated carbon particles, inorganic particles, and hygroscopic resins. These may be used alone or in combination of two or more materials.

The activated carbon particles contained in the oxygen scavenger and oxygen scavenger-containing coating of the present invention mean porous carbon particles having fine pores. Although the particle size is not particularly limited, the median diameter is preferably 50 μm or less, more preferably 30 μm or less, from the viewpoint of dispersion stability in the coating composition and suppression of coating unevenness. It is more preferably 10 μm or less, and particularly preferably 1 μm or less.
Production raw materials are not particularly limited, and examples thereof include coal, coconut shells, and large sawdust. Further, the production method is not particularly limited, and a gas activation method or a chemical activation method can be used.
As the activated carbon particles, commercially available products may be used, for example, “Shirakaba” manufactured by Nippon Enviro Chemicals, “Kuraray Coal” manufactured by Kuraray Chemical Co., “Dia Hope” manufactured by Mitsubishi Chemical Calgon Co., “Calgon”, etc. it can.
Here, the median diameter of the activated carbon particles is measured by a dynamic light scattering method which is generally used for measuring the particle diameter of the fine particles.

Examples of the inorganic particles contained in the oxygen scavenger or oxygen scavenger-containing coating of the present invention include metal oxide fine particles that are stable in an acidic region such as silica, alumina, and titania. These may be used alone or in combination. Of these, silica and alumina are preferable from the viewpoint of cost and effect.
The particle size is not particularly limited, but the median diameter is preferably 10 μm or less, more preferably 5 μm or less, from the viewpoint of dispersion stability in the coating composition and suppression of coating unevenness. It is more preferably 1 μm or less, and particularly preferably 0.1 μm or less. The shape when added to the coating is not particularly limited, but is preferably a sol shape from the viewpoint of mixing stability and ease of handling.
Commercially available inorganic particles may be used, for example, “NIPGEL” manufactured by Tosoh Silica Co. as silica, “Snowtex” manufactured by Nissan Chemical Co., Ltd. as silica sol, “Alumina sol” manufactured by Nissan Chemical Co., Ltd., etc. can do.
Here, the median diameter of the inorganic particles is measured by a dynamic light scattering method generally used for measuring the particle diameter of the fine particles.

The hygroscopic resin contained in the oxygen scavenger and oxygen scavenger-containing coating of the present invention means a resin having a saturated moisture absorption rate exceeding 15% at a temperature of 20 ° C. and a humidity of 65%. The saturated moisture absorption is preferably over 20%, more preferably over 30%, and particularly preferably over 40%. The hygroscopic resin may be dissolved or dispersed in the deoxidizing coating of the present invention. The resin particle size in the case of dispersion is not particularly limited, but the median diameter is preferably 50 μm or less, preferably 30 μm or less from the viewpoint of dispersion stability in the coating material and suppression of coating unevenness. Is more preferably 10 μm or less, and particularly preferably 1 μm or less.
The resin type is not particularly limited, and examples thereof include acrylic resins, polyvinyl alcohol resins, polyethylene oxide resins, starches, and celluloses. Further, the production method is not particularly limited.
Here, the median diameter of the resin particles is measured by a dynamic light scattering method generally used for measuring the particle diameter of the fine particles.

  The transition metal compound contained in the oxygen scavenger and oxygen scavenger-containing coating of the present invention is a salt compound of a transition metal ion and an inorganic acid or an organic acid, or a complex compound of an organic compound, water Either a hydrate or an anhydride can be used. Examples of the transition metal include iron, copper, manganese, vanadium, chromium, cobalt, nickel, and zinc. The transition metal compound may be used alone or as a mixture. Specific examples include iron chloride, iron citrate, ammonium iron citrate, iron stearate, copper citrate, copper stearate, copper chloride and the like. From the viewpoint of safety, iron citrate is preferable.

  The hygroscopic material and the transition metal compound may be used alone or in combination. The combined use of the hygroscopic material and the transition metal compound can further improve the deoxygenation ability of the coating film. Further, when a transition metal compound and a hygroscopic material other than activated carbon are used in combination, a coating material having an arbitrary appearance (color) can be prepared. In other words, activated carbon particles are a very effective hygroscopic material in terms of improving the deoxygenation ability of the coating film, but if used, the appearance of the coating film tends to be black, and the appearance (color) of the coating film is adjusted. It becomes difficult. However, even if the hygroscopic material is slightly inferior in the effect of improving the oxygen scavenging ability, it can be supplemented by using a transition metal compound in combination. Improvement of deoxygenation ability can be expected.

  The oxygen scavenger of the present invention contains the polyolefin resin A having the specific composition described above, an organic oxygen absorber, a hygroscopic material and / or a transition metal compound, and the polyolefin resin A and the organic oxygen absorber. The total concentration (solid content concentration) of the hygroscopic material and / or transition metal compound is preferably 1 to 40% by mass, more preferably 3 to 35% by mass, and even more preferably 5 to 25% by mass. When the solid content concentration is less than 1% by mass, it is difficult to form a coating film having a sufficient thickness when applied to the substrate. On the other hand, when the solid content concentration exceeds 40% by mass, the polyolefin resin and the hygroscopic material in the present invention and / or Or the dispersibility in the aqueous medium of a transition metal compound may fall.

Further, the mass ratio of the organic oxygen absorber, the polyolefin resin A, the hygroscopic material, and / or the transition metal compound contained in the oxygen absorber coating or oxygen absorber-containing coating of the present invention is not particularly limited. However, considering the adhesion to the base material and the deoxidizing effect of the deoxidizing coating agent when the coating film is formed, the mass ratio of the polyolefin resin A and the organic deoxidizing agent (polyolefin resin A / organic deoxygenating agent) Is preferably 1/99 to 99/1, more preferably 5/95 to 90/10, and even more preferably 10/90 to 80/20.
The content of the moisture-absorbing material is preferably 0.1 to 35% by mass in terms of the total solid content in consideration of the adhesion to the substrate and the deoxygenating effect of the deoxidizing coating agent when it is formed into a coating film. More preferably, it is 5-30 mass%, and it is especially preferable that it is 1-25 mass%. If it is less than 0.1% by mass, the effect of addition cannot be obtained, and if it exceeds 35% by mass, the adhesion to the substrate may be lowered.
The content of the transition metal compound is preferably 0.1 to 50% by mass of the organic oxygen scavenger, more preferably 0.5 to 30% by mass, and 1 to 10% by mass. Particularly preferred. If the amount is less than 0.1% by mass, it is difficult to obtain the effect.

  The deoxygenating coating of the present invention is a deoxygenating agent containing an acidic compound in an aqueous medium in addition to the organic deoxygenating agent as described above, the polyolefin resin of the present invention, and a hygroscopic material and / or a transition metal compound. It is an oxygen paint. In addition, the aqueous medium in the deoxidation coating agent of this invention means water or the liquid mixture of water and an organic solvent.

  In the present invention, by containing this acidic compound, part or all of the amino groups in the polyolefin resin can be neutralized as described above. An amino cation is generated in the polyolefin resin by neutralization of the amino group, and aggregation between the polyolefin resin particles in the aqueous medium can be prevented by the electrostatic repulsion between the generated amino cations. The deoxygenating coating material of the present invention is a cationic aqueous coating material in which a polyolefin resin is uniformly dispersed and is stable in an acidic region.

  Conventionally, as a method of uniformly dispersing a polyolefin resin in an aqueous medium, a polyolefin resin having a carboxyl group at its terminal and a basic compound (specifically, organic compounds such as ammonia, triethylamine, N, N-dimethylethanolamine, etc.) There is a method of neutralizing a polyolefin resin with a basic compound by containing an amine compound). At this time, carboxyl anions are generated by neutralization, and electrostatic repulsion between the generated carboxyl anions can prevent aggregation between polyolefin resin particles in an aqueous medium, and can impart dispersion stability. .

  When such a polyolefin resin having a carboxyl group is used, in order to maintain the dispersion stability of the polyolefin resin, it is necessary to maintain an aqueous dispersion in which the polyolefin resin is dispersed in an aqueous medium in the basic region. If an organic oxygen scavenger such as ascorbic acid is added to the aqueous dispersion in the basic region, the stability of the aqueous dispersion is reduced and the polyolefin resin is agglomerated or the organic oxygen scavenger is significantly decomposed. The problem of being promoted arises. Therefore, it is preferable that the oxygen scavenger containing an organic oxygen scavenger is maintained in a neutral to acidic region.

  Therefore, in the coating agent of the present invention, by using an acidic compound together with the polyolefin resin A as described above, a cationic aqueous dispersion that is stable in an acidic region in which the polyolefin resin A is uniformly dispersed in an aqueous medium is obtained. Therefore, the organic oxygen scavenger can be contained stably, in other words, the decomposition is not significantly accelerated.

  The acidic compound in the present invention preferably has an acid dissociation constant (pKa) of 8 or less, more preferably −9 to 7, more preferably −5 to 6, and particularly preferably 0 to 5. When the acid dissociation constant (pKa) exceeds 8, the amino group is hardly neutralized, and aqueous dispersion of the polyolefin resin A tends to be difficult. However, if it is too low, it is highly corrosive and may damage equipment for aqueous dispersion and equipment for using an aqueous dispersion. There is also a concern that the decomposition of the organic oxygen scavenger is significantly accelerated.

  Specific examples of acidic compounds having an acid dissociation constant (pKa) of 8 or less include organic acids such as formic acid, acetic acid, propionic acid, butyric acid, valeric acid and lactic acid; inorganic acids such as hydrochloric acid, sulfuric acid, phosphoric acid and nitric acid. Among these, organic acids that are relatively low in corrosivity and excellent in neutralization of amino groups are preferable, and formic acid and acetic acid are more preferable.

  Moreover, it is preferable that the acidic compound is not contained in the oxygen scavenger-containing coating film of the present invention. If the oxygen scavenger-containing coating film of the present invention contains an acidic compound, the adhesion to the substrate may be lowered or the water resistance may be lowered. For this reason, it is preferable that an acidic compound is volatile, specifically, it is preferable that a boiling point is 20-250 degreeC, 30-200 degreeC is more preferable, 50-150 degreeC is further more preferable, 50-120 ° C is particularly preferred.

  If the acidic compound is non-volatile or has a boiling point that is too high, the acidic compound tends to remain in the oxygen scavenger-containing coating film of the present invention. If the boiling point is too low, the proportion of volatilization during aqueous dispersion increases, and the amino group in the side chain of the polyolefin resin in the present invention may not be sufficiently neutralized.

  The deoxidizing paint of the present invention preferably has a pH of 2-6. If the pH of the coating exceeds 6, the storage stability of the coating may be poor. On the other hand, when the pH is less than 2, the amount of the acidic compound added increases, which may cause an increase in cost, increase the drying time when forming the coating film, or significantly accelerate the decomposition of the organic oxygen scavenger. is there.

  In order to make the pH of the deoxidizing coating within this range, it is possible to adjust the content of the acidic compound. The content of the acidic compound is the type of the polyolefin resin A, the ratio of the polyolefin resin A to the organic oxygen scavenger, the content of the hygroscopic material and / or the transition metal compound, the polyolefin resin A in the coating material and the organic oxygen scavenger. Although it varies depending on the total concentration (solid content concentration) of the oxygen agent, the hygroscopic material, and / or the transition metal compound, the molar equivalent of 0.5 to 5 times the molar number of amino groups of the polyolefin resin A is preferable, and 0.8 -3 times equivalent mol is more preferable, and 1-2.5 times equivalent mol is more preferable.

  It is preferable that the deoxygenating coating material of the present invention substantially does not contain a nonvolatile aqueous dispersion aid. When the non-volatile aqueous dispersion aid is contained, it remains in the coating film obtained by applying the coating agent, and the coating film is plasticized or hydrophilized. For this reason, the adhesiveness to the base material of a coating film, water resistance, solvent resistance, etc. fall. In addition, there is a concern that the non-volatile auxiliary agent bleeds out to the surface of the coating film to reduce the deoxygenation function.

  Here, “substantially free of non-volatile aqueous dispersion aid” means that the non-volatile aqueous dispersion aid is not actively added to the deoxidized coating agent, and is 100 parts by mass of polyolefin resin A. It means that the content of the non-volatile aqueous dispersion aid is less than 0.1 parts by mass, and preferably this content is zero. Nonvolatile means that it does not have a boiling point at normal pressure or has a high boiling point (for example, 300 ° C. or higher) at normal pressure.

  "Nonvolatile aqueous dispersion aid" refers to a nonvolatile drug or compound added for the purpose of promoting aqueous dispersion or stabilizing aqueous dispersion in aqueous dispersion of polyolefin resin A. Specific examples include emulsifiers. Examples of the emulsifier include a cationic emulsifier, an anionic emulsifier, a nonionic emulsifier, and an amphoteric emulsifier. In addition to those generally used for emulsion polymerization, surfactants are also included. For example, anionic emulsifiers include higher alcohol sulfates, higher alkyl sulfonates, higher carboxylates, alkyl benzene sulfonates, polyoxyethylene alkyl sulfate salts, polyoxyethylene alkyl phenyl ether sulfate salts, vinyl sulfosuccinates. Nonionic emulsifiers include polyoxyethylene alkyl ether, polyoxyethylene alkyl phenyl ether, polyethylene glycol fatty acid ester, ethylene oxide propylene oxide block copolymer, polyoxyethylene fatty acid amide, ethylene oxide-propylene oxide. Compounds having a polyoxyethylene structure such as copolymers and sorbitan derivatives such as polyoxyethylene sorbitan fatty acid esters Examples of the cationic emulsifier include quaternary ammonium salts such as alkyltrimethylammonium salt and dialkyldimethylammonium salt, and alkylamine salts. Examples of the amphoteric emulsifier include laurylbetaine, lauryldimethylamine oxide, and the like. It is done.

  In the present invention, the aqueous medium refers to water or a mixed liquid of water and an organic solvent. When the aqueous medium contains an organic solvent, the coating property to the substrate can be improved.

  The content of the organic solvent in the oxygen scavenger of the present invention is the ratio of the polyolefin resin A and the organic oxygen absorber, the content of the moisture absorbing material and / or the transition metal compound, the polyolefin resin A and the organic oxygen absorber. Although it is variously adjusted according to the total concentration (solid content concentration), pH, type of organic solvent, and use of the hygroscopic material and / or transition metal compound, it is preferably 1 to 97% by mass in the coating composition. 5 to 95% by mass, more preferably 10 to 90% by mass, and particularly preferably 20 to 80% by mass. When the organic solvent content exceeds 97% by mass, the storage stability of the coating may be lowered. When it is less than 1% by mass, the effect of improving the coating property tends to be poor.

  Further, when the aqueous dispersion of polyolefin resin A described later is added, an organic solvent is added so that the content of amino groups is small, or the nonvolatile aqueous dispersion aid is not substantially added. The dispersion of the polyolefin resin in the aqueous medium in the invention can be promoted, and the particle diameter of the polyolefin resin in the invention can be reduced.

  In the aqueous dispersion of the polyolefin resin in the present invention, the content of the organic solvent in the aqueous medium is preferably 50% by mass or less, more preferably 1 to 40% by mass, and more preferably 2 to 35% by mass. More preferably, 3-30 mass% is especially preferable. When the content of the organic solvent exceeds 50% by mass, the effect of promoting aqueous dispersion tends to be unchanged or reduced.

  The organic solvent preferably has a solubility in water at 20 ° C. of 50 g / L or more, more preferably 100 g / L or more, and 600 g in order to improve the storage stability of the deoxygenating coating. / L or more is more preferable, and it is particularly preferable that it dissolves at an arbitrary ratio with water at 20 ° C.

  Moreover, it is preferable that the boiling point of an organic solvent is 30-250 degreeC, and it is more preferable that it is 50-200 degreeC. When the boiling point of the organic solvent is less than 30 ° C., the proportion of volatilization during preparation or storage of the deoxidized coating agent or during coating increases, and the effect of addition may not be sufficiently enhanced. Moreover, also in the aqueous dispersion of polyolefin resin A described later, the volatilization ratio increases, and the dispersion efficiency may not be sufficiently increased. When the boiling point exceeds 250 ° C., it tends to remain in the coating film obtained from the coating agent, and the adhesiveness to the substrate, water resistance and solvent resistance tend to decrease.

  Specific examples of the organic solvent having a solubility in water at 20 ° C. of 50 g / L or more and a boiling point of 30 to 250 ° C. include methanol, ethanol, n-propanol, isopropanol, n-butanol, isobutanol, sec-butanol. , Tert-butanol, n-amyl alcohol, isoamyl alcohol, sec-amyl alcohol, tert-amyl alcohol, 1-ethyl-1-propanol, 2-methyl-1-butanol, n-hexanol, cyclohexanol and the like; Ketones such as methyl ethyl ketone, methyl isobutyl ketone, ethyl butyl ketone, cyclohexanone and isophorone, ethers such as tetrahydrofuran and dioxane; ethyl acetate, n-propyl acetate, isopropyl acetate, and n-butyl acetate , Isobutyl acetate, sec-butyl acetate, 3-methoxybutyl acetate, methyl propionate, ethyl propionate, diethyl carbonate, dimethyl carbonate, etc., ethylene glycol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene Glycol monopropyl ether, ethylene glycol monobutyl ether, ethylene glycol ethyl ether acetate, diethylene glycol, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, diethylene glycol ethyl ether acetate, propylene glycol, propylene glycol monomethyl ether, propylene glycol monobutyl ether, propylene Glycol glycol derivatives such as methyl ether acetate; more, 3-methoxy-3-methylbutanol, 3-methoxybutanol, acetonitrile, dimethylformamide, dimethylacetamide, diacetone alcohol, ethyl acetoacetate, and the like. In addition, you may use these organic solvents in mixture of 2 or more types.

  Among the above, from the viewpoint of price and handling, ethanol, n-propanol, isopropanol, n-butanol, methyl ethyl ketone, cyclohexanone, tetrahydrofuran, dioxane, ethylene glycol monoethyl ether, ethylene glycol monopropyl ether, ethylene glycol monobutyl ether are preferable. Ethanol, n-propanol, isopropanol and tetrahydrofuran are particularly preferred.

  In addition, to the deoxidizing paint of the present invention, addition of a resin other than the polyolefin resin in the present invention, a leveling agent, an antifoaming agent, an antioxidant, an ultraviolet absorber, a coloring agent, etc., as long as the characteristics are not impaired. Things may be added.

  Especially, the hardness of the coating film obtained can be raised by adding a crosslinking agent. As a crosslinking agent, a crosslinking agent having a self-crosslinking property; a compound having a plurality of functional groups that react with an amino group, an acrylate ester or a carboxyl group in a molecule; a metal complex having a multivalent coordination site, or the like is used. Specifically, hydrazide compounds, isocyanate compounds, melamine compounds, urea compounds, epoxy compounds, carbodiimide compounds, oxazoline group-containing compounds, zirconium salt compounds, silane coupling agents, organic peroxides, and the like are preferable. Two or more of these crosslinking agents may be used in combination.

Next, a method for producing the deoxidizing paint of the present invention will be described.
As a method for obtaining an oxygen scavenger comprising an organic oxygen scavenger as described above, a polyolefin resin having a specific composition, a hygroscopic material and / or a transition metal compound, an acidic compound, and an aqueous medium, dispersion stability of the polyolefin resin A can be obtained. From the viewpoint of properties, the method of preparing an aqueous dispersion of polyolefin resin A in advance and mixing it with an organic oxygen absorber, a hygroscopic material and / or a transition metal compound is most preferable. In this way, excellent dispersion and storage stability of the aqueous polyolefin resin dispersion can be maintained, and organic deoxygenation can be achieved by mixing with an organic deoxygenating agent, a hygroscopic material and / or a transition metal compound when necessary. It becomes easy to maintain the function of the agent. Hereinafter, this method will be described in detail.

First, the manufacturing method of the aqueous dispersion of polyolefin resin A is demonstrated.
As an aqueous dispersion method for obtaining an aqueous dispersion of polyolefin resin A, a method of heating and stirring together with an acidic compound and an aqueous medium in a sealable container is preferable. Any container may be used as long as it is equipped with a tank into which a liquid can be charged and the mixture of the acidic compound, the aqueous medium and the resin powder or the granular material charged in the tank can be appropriately stirred. As such an apparatus, a solid / liquid stirring apparatus or an emulsifier can be used, and it is preferable that the apparatus is pressure resistant. The stirring method and the rotation speed of the stirring are not particularly limited, but sufficient aqueous formation can be achieved even with low-speed stirring at which the resin is in a floating state in an aqueous medium, and high-speed stirring (for example, 1000 rpm or more) is not essential. For this reason, the aqueous dispersion can be produced with a simple apparatus.

A polyolefin resin A, an acidic compound, and an aqueous medium (water and an organic solvent) are charged into the container as described above, and then the temperature in the tank is 80 to 250 ° C, preferably 90 to 200 ° C, more preferably 100 to 100 ° C. While maintaining the temperature at 190 ° C., the polyolefin resin A can be sufficiently dispersed by preferably continuing stirring for 5 to 180 minutes. Thereafter, the aqueous dispersion can be obtained by cooling to 40 ° C. or lower, preferably with stirring. When the temperature in the tank is less than 80 ° C., the dispersion effect of the polyolefin resin A is low, and even if the temperature exceeds 250 ° C., the effect of aqueous dispersion is not further improved.
According to this method, an aqueous dispersion in which the polyolefin resin A is well dispersed can be obtained without substantially adding a non-volatile aqueous additive.

  The aqueous dispersion obtained by the above-described method is very well dispersed, and there is little or no undispersed resin remaining. However, a filtration step may be provided when the aqueous dispersion is dispensed in order to remove foreign substances in the container and a small amount of undispersed resin. Although the filtration method is not limited, For example, the method of carrying out pressure filtration (for example, air pressure 0.5MPa) with a 300 mesh stainless steel filter (wire diameter 0.035mm, plain weave) is mentioned. By providing such a filtration step, even if an undispersed resin is present, it can be removed, so that the use of an aqueous dispersion is not a problem in subsequent steps.

  As described above, an aqueous dispersion in which the polyolefin resin A is uniformly dispersed in an aqueous medium is prepared.

  The number average particle size of the polyolefin resin A in the aqueous dispersion is preferably 1000 nm or less, more preferably 500 nm or less, more preferably 200 nm or less, still more preferably 100 nm or less, and particularly preferably 90 nm or less. Preferably, 80 nm or less is most preferable. When the number average particle diameter exceeds 1000 nm, the storage stability of the aqueous dispersion tends to decrease, or the film-forming property when applied tends to be non-uniform.

  Furthermore, the volume average particle diameter of the polyolefin resin A in the aqueous dispersion is preferably 1000 nm or less, preferably 500 nm or less, more preferably 200 nm or less, still more preferably 100 nm or less, and particularly preferably 90 nm or less. When the volume average particle diameter of the polyolefin resin A exceeds 1000 nm, the storage stability of the aqueous dispersion tends to decrease, or the film-forming property upon application tends to be non-uniform.

  Further, a part of the organic solvent contained in the aqueous dispersion of polyolefin resin A can be removed from the aqueous dispersion by a solvent removal operation called stripping. By such stripping, the content of the organic solvent can be reduced to 0.1% by mass or less as necessary. Even if the content of the organic solvent is 0.1% by mass or less, there is no influence on the performance of the aqueous dispersion. Examples of the stripping method include a method in which the aqueous dispersion is heated with stirring at normal pressure or reduced pressure to distill off the organic solvent.

  As the solid content concentration of the polyolefin resin A contained in the aqueous dispersion, the aqueous dispersion is used in order to maintain good mixing stability and coating properties when used as a deoxygenating coating, and thickness when applied. 2-60 mass% is preferable, 5-50 mass% is more preferable, 10-45 mass% is further more preferable.

  By mixing the aqueous dispersion of polyolefin resin A obtained as described above, an organic oxygen absorber, a hygroscopic material, and / or a transition metal compound, the oxygen absorber of the present invention can be obtained. In mixing, a known apparatus can be used. A special mixing device is not necessarily required, and stirring with a general stirring blade is sufficient, but a homogenizer, a homomixer, a paint shaker, a planetary stirring device, or the like may be used. In addition, in order to maintain the dispersion stability of the deoxidized coating material of the present invention, it is preferable to adjust the pH so that the pH of the aqueous dispersion becomes 2-6.

  In addition, as a method for adjusting the total concentration (solid content concentration) of the polyolefin resin A, the organic oxygen absorber, the hygroscopic material and / or the transition metal compound in the oxygen scavenger of the present invention, for example, The method of distilling an aqueous medium, the method of diluting with water, the above-mentioned organic solvent, etc. are mentioned, and adjustment of total concentration is possible easily.

Next, the coating film and laminate of the present invention will be described.
The deoxygenation coating agent of the present invention is excellent in film forming property (coating film forming property), and can form a coating film easily by coating and drying. Furthermore, since it has excellent adhesion to a wide variety of substrates such as resin materials, paper, synthetic paper, fabrics, metal materials, and glass materials, these materials can be used as the substrate.
The laminate of the present invention is obtained by laminating the oxygen scavenger-containing coating film of the present invention on a substrate. The oxygen scavenger-containing coating on the substrate is preferably obtained by applying the oxygen scavenger of the present invention.

  The thickness of the oxygen scavenger-containing coating in the laminate of the present invention can be appropriately selected depending on the form and required performance, but is preferably 0.05 to 1000 μm, more preferably 0.1 to 100 μm. Preferably, 0.2-50 micrometers is especially preferable.

  Examples of paper that can be used for the substrate include Japanese paper, craft paper, liner paper, art paper, coated paper, carton paper, glassine paper, semi-glassine paper, and the like.

  The structure of the synthetic paper that can be used for the substrate is not particularly limited, and may be a single layer structure or a multilayer structure. As a multilayer structure, for example, a two-layer structure of a base material layer and a surface layer, a three-layer structure in which a surface layer exists on the front and back surfaces of the base material layer, and another resin film layer exists between the base material layer and the surface layer. A multilayer structure can be exemplified. Each layer may contain an inorganic or organic filler. A microporous synthetic paper having a large number of fine voids can also be used.

  Resin materials that can be used for the substrate include polyester resins such as polyethylene terephthalate (PET), polyethylene naphthalate (PEN), and polylactic acid (PLA), polyolefin resins such as polyethylene (PE) and polypropylene (PP), and polystyrene. Resin, 6-nylon, polyamide resin such as poly-m-xylylene adipamide (MXD6 nylon), polycarbonate resin, polyacrylonitrile resin, polyimide resin, and multilayers of these resins (for example, nylon 6 / MXD / Nylon 6, nylon 6 / ethylene-vinyl alcohol copolymer / nylon 6), mixtures and the like.

  Base materials made of these resin materials include those formed into a plate shape by injection molding, etc., those melted and stretched into a sheet shape, those obtained by further stretching a sheet into a film shape, resin materials or raw materials thereof. Examples include a solution obtained by coating and drying the solution. These resins may contain known additives and stabilizers such as antistatic agents, plasticizers, lubricants, antioxidants and the like. Moreover, in order to improve the adhesiveness when laminating with other materials, the surface of the base material made of a resin material may be subjected to corona treatment, plasma treatment, ozone treatment, chemical treatment, solvent treatment and the like. Furthermore, silica, alumina or the like may be deposited.

  Examples of the fabric that can be used for the substrate include fibers made of the above-described synthetic resins, and woven and knitted fabrics and nonwoven fabrics using natural fibers such as cotton, silk, and hemp.

  Examples of metal materials that can be used for the substrate include metal foils such as aluminum foil and copper foil, and metal plates such as aluminum plates and copper plates. Examples of glass materials include glass plates and fabrics made of glass fibers. Is mentioned.

  As a method of providing the oxygen scavenger-containing coating film of the present invention on a substrate, a method of removing an aqueous medium or the like from the oxygen scavenger after applying the oxygen scavenger coating of the present invention on the substrate, on a release paper And a method of transferring a coating film obtained by applying the deoxidizing coating agent of the present invention to remove an aqueous medium or the like onto a substrate. Among these, the former method is simple and preferable.

  Since the deoxidizing coating composition of the present invention is excellent in film forming property, when coating, known film forming methods such as gravure roll coating, reverse roll coating, wire bar coating, lip coating, air knife coating, curtain A flow coating method, a spray coating method, a dip coating method, a brush coating method, or the like can be employed, and it can be uniformly applied to various substrate surfaces. After coating, if necessary, the temperature is set near room temperature, followed by drying or heat treatment for drying and baking to remove the aqueous medium and the like. As a result, it is possible to obtain a laminate in which a uniform coating film is well adhered (adhered) to the substrate surface.

  When performing heat treatment for drying or drying and baking, a normal hot air circulation type oven, an infrared heater, or the like may be used. Further, the heating temperature and the heating time are appropriately selected depending on the properties and types of the coating agent and the base material. However, in consideration of economy, the heating temperature is preferably 30 to 250 ° C., 60 to 200 ° C. is more preferable, 80 to 180 ° C. is particularly preferable, and the heating time is preferably 1 second to 20 minutes, more preferably 5 seconds to 15 minutes, and particularly preferably 5 seconds to 10 minutes. As described above, when a cross-linking agent is added to the deoxidized coating composition of the present invention, it is desirable to appropriately select the heating temperature and time depending on the type of the cross-linking agent in order to sufficiently advance the cross-linking reaction.

  Since the oxygen scavenger-containing coating film of the present invention contains the polyolefin resin A, it has heat sealability. Therefore, as a laminate of the present invention, when a resin film, a sheet, synthetic paper, or a metal foil is used as a base material, an oxygen scavenger-containing coating film is overlapped and heat-treated to form a package. You can also Examples of such a package include a three-side seal bag, a four-side seal bag, a gusset packaging bag, and a pillow packaging bag.

  Furthermore, the laminate of the present invention preferably has a sealant layer laminated on the oxygen scavenger-containing coating film. The sealant layer does not exhibit adhesiveness at room temperature and has heat sealability. By providing the sealant layer, the heat sealability can be further improved, which is suitable for the above-described package.

  The method for providing the sealant layer is not particularly limited, but a sealant resin described later is formed into a sheet or film, placed on the coating surface of the laminate of the present invention, and bonded by heat (thermal lamination, dry lamination), Examples thereof include a method of extruding and bonding a melted sealant resin to the coating surface of the laminate of the present invention (extrusion laminating method).

  Since the oxygen-absorbing agent-containing coating film of the present invention contains the polyolefin resin A, since it has excellent laminating suitability, any laminating method can be used, but the extrusion laminating method, which is the most economical method, This is an optimum method capable of exhibiting the performance of the deoxidizing paint of the present invention.

  The thickness of the sealant layer is preferably in the range of 10 to 50 μm, and more preferably in the range of 20 to 40 μm. If the sealant layer exceeds 50 μm, the deoxygenation reaction may take time. On the other hand, if the thickness of the sealant layer is less than 10 μm, the effect of providing the sealant layer is poor.

  As the resin forming the sealant layer, a known sealant resin can be used. Specifically, polyethylene such as low density polyethylene (LDPE) and high density polyethylene (HDPE), acid-modified polyethylene, polypropylene, acid-modified polypropylene, copolymerized polypropylene, ethylene-vinyl acetate copolymer, ethylene- (meth) acrylic Examples include acid ester copolymers, ethylene- (meth) acrylic acid copolymers, polyolefin resins such as ionomers, and thermoplastic resins such as polyester resins and acrylic resins such as polyacrylonitrile. Among them, polyethylene having excellent low-temperature heat sealability Polyethylene is particularly preferred because it is preferably a resin and is inexpensive.

  Further, in a laminate having a sealant layer, a polypropylene resin chuck may be provided on the sealant layer to form a packaging bag with a chuck.

  Furthermore, in the laminate of the present invention, it is preferable that the substrate has a barrier property. When the base material has barrier properties, for example, in the case of a package, it is possible to prevent oxygen from being mixed from the outside.

  The base material having a barrier property was formed from a soft metal foil such as an aluminum foil, or a resin material having a barrier property such as a vinylidene chloride resin, a modified polyvinyl alcohol, an ethylene vinyl alcohol copolymer, or MXD nylon. Examples thereof include a base material and a base material obtained by laminating a barrier layer on a base material formed from a material having no barrier property.

  Examples of the barrier layer include a soft metal foil such as an aluminum foil, a vapor deposition layer such as aluminum vapor deposition, silica vapor deposition, alumina vapor deposition, and silica alumina binary vapor deposition, and a layer made of the above-described resin material having a barrier property. .

The barrier property of the substrate having a barrier property may be appropriately selected depending on the use such as the contents to be packaged and the storage period, but the oxygen permeability is 100 ml / m ² · day · MPa (20 ° C., 90% RH) or less. is preferably, more preferably less ^{20ml / m 2 · day · MPa} , 10ml / m 2 · day · MPa more preferably ^{less, 1ml / m 2 · day ·} MPa or less are particularly preferred. The water vapor permeability is preferably 100 g / m ² · day (40 ° C., 90% RH) or less, more preferably 20 g / m ² · day or less, still more preferably 10 g / m ² · day or less, and 1 g / m. ² · day or less is particularly preferable.

  As the base material having a barrier property, a base material obtained by laminating a barrier layer on a base material formed from a material having no barrier property is preferable. From the viewpoint of the barrier property, an aluminum foil or aluminum is preferable as the barrier layer. Further, a vapor deposition layer such as silica and alumina is preferable, and an aluminum foil is more preferable because it is inexpensive. Although the thickness of aluminum foil is not specifically limited, The range of 3-50 micrometers is preferable from an economical surface.

  As a base material on which a vapor deposition layer such as aluminum, silica, and alumina is laminated, it is easy to use a commercially available vapor deposition film. As such a vapor deposition film, for example, “IB series” manufactured by Dai Nippon Printing Co., Ltd. "GL, GX series" manufactured by Toppan Printing Co., Ltd., "Barrier Rocks", "VM-PET", "YM-CPP", "VM-OPP" manufactured by Toray Film Co., Ltd., "Tech Barrier" manufactured by Mitsubishi Plastics "Metaline" manufactured by Tosero Co., Ltd., "MOS", "Tetrait", and "Bright" manufactured by Oike Kogyo Co., Ltd. can be used. A protective coat layer may be provided on the vapor deposition layer.

  In addition, as the base material having a barrier property, there are those in which a coating material containing a barrier resin is coated on the base material and those in which the resin is laminated on the base material by a co-extrusion method. Is preferable because it is simple.

  Commercially available barrier films include Kuraray's "Clarista" and "Eval", Kureha Chemical Industry's "Besera", Mitsubishi Plastics' "Super Neal", Kojin's "Co-Barrier", and Unitika "Savix", "Embron M", "Embron E", "Emblem DC", "Embret DC", "NV", manufactured by Tosero "K-OP", "A-OP", manufactured by Daicel "Senesi" and so on.

  As a method of laminating the coating film of the present invention on a substrate having a barrier property, after applying the deoxidizing coating agent of the present invention on the substrate having the barrier property described above, it is dried to obtain an aqueous medium or the like. A method of removing, a method of transferring a coating film obtained by applying the deoxidizing coating agent of the present invention on a release paper and then drying to remove an aqueous medium etc. onto a substrate having a barrier property The former method is simple and preferable.

  Further, as a method of obtaining a laminate of the present invention having a sealant layer using a substrate having a barrier property, for example, the deoxidizing coating agent of the present invention is applied onto a substrate having a barrier property, A method of laminating the sealant layer by removing the aqueous medium by drying to form a coating film and then melt-extruding (extrusion laminating) the resin in-line is simple and particularly preferred.

  Furthermore, in the laminate of the present invention, it is preferable that a moisture absorbing layer is laminated on at least one of the upper and lower sides of the oxygen scavenger-containing coating film. The hygroscopic layer is a layer containing the hygroscopic material described above. By providing such a moisture-absorbing layer, it is possible to suppress the degradation of inclusions that dislike moisture by promoting moisture trapping in the bag when it is in the form of a bag, etc. This is preferable because the deoxygenation reaction can be further improved.

  The thickness of the moisture absorption layer can be appropriately selected depending on the form and required performance, but is preferably 0.05 to 1000 μm, more preferably 0.1 to 100 μm, and particularly preferably 0.2 to 50 μm. .

  The hygroscopic layer may be a layer containing the above-described hygroscopic material, and is not particularly limited, but preferably includes a resin component for holding the hygroscopic material. The type of resin is not particularly limited, and polyester resins, polyolefin resins, polyamide resins, acrylic resins, polyurethane resins, and the like can be used. Further, the content of the hygroscopic material in the hygroscopic layer is not particularly limited.

  The method for providing the moisture absorbing layer is not particularly limited, but the above-described resin containing the moisture-absorbing material is formed into a sheet or film and laminated by heat, the molten resin containing the moisture-absorbing material is extruded and laminated, and the above-described moisture absorbing layer. Examples thereof include a method of applying and laminating a coating material containing a material and a resin component.

  In the laminate of the present invention, other layers can be provided as long as the effects as described above are not impaired, specifically, a printing layer, an antistatic layer, an ultraviolet absorbing layer, an adhesive layer, An adhesive layer or the like may be laminated.

  The deoxidant-containing coating film of the present invention exhibits a deoxygenation function when moisture comes close to it. For this reason, as long as moisture is not in close proximity, it can be stored in the atmosphere for a long time without having to maintain a special environment, and there is no problem in use after long-term storage.

  Even in a laminate in which a sealant layer is laminated on a coating film, a deoxygenation reaction proceeds, so that a bag can be made and a liquid can be sealed.

  When the laminate of the present invention is used to develop a deoxygenation function, gas or liquid moisture is preferably used as moisture to be brought close to, and liquid is most preferred because of the wide range of use. Its liquidity is preferably acidic or basic rather than neutral.

  When bringing the liquid close, moisture may be brought into direct contact with the coating film or sealant layer of the laminate, or moisture may be adsorbed on a water-absorbing material and the material may be brought into contact with the coating film or sealant layer. . When using the laminated body of this invention as a packaging material, the water | moisture content derived from the content can also be used as a method of making a water | moisture content contact a laminated body directly. That is, when the laminate is used as a packaging material and an article holding a liquid or moisture is enclosed in the packaging material, a deoxidation function starts to appear.

  Moreover, when water | moisture content is adsorbed | sucked to the material which has water absorption, any material derived from a plant, animal origin, petroleum origin, and a mineral can be used as a material which has water absorptivity. Any shape can be used as long as it can contact the deoxidation layer, such as a sheet shape, a thread shape, a cotton shape, a gel shape, and a clay shape. Specifically, paper, a nonwoven fabric, a woven / knitted fabric, an activated carbon sheet, etc. are mentioned.

  The activated carbon sheet is a sheet of activated carbon (a substance mainly composed of porous carbon). The manufacturing method of activated carbon and an activated carbon sheet is not specifically limited, A commercial item can also be used. For example, “activated carbon fiber sheet” manufactured by Unitika Ltd., “AFT activated carbon sheet” manufactured by Ajinomoto Fine Techno Co., “kura sheet” manufactured by Kuraray Chemical Co., Ltd. and the like can be exemplified.

The present invention will be specifically described below with reference to examples. Various characteristic values in the examples were measured or evaluated by the following methods.
1. Characteristics of acid anhydride-containing copolymer and polyolefin resin (1) Structure
^It calculated | required from < ¹ > H-NMR analysis (ECA500, 500MHz by JEOL Ltd.). Tetrachloroethane (d ₂ ) was used as a solvent and measurement was performed at 120 ° C.
(2) Mass average molecular weight measurement A GPC apparatus (model HLC-8020GPC, column is TSK-GEL) manufactured by Tosoh Corporation was used. The eluent was orthodichlorobenzene, and the mass average molecular weight was measured at 40 ° C. It calculated | required from TSK standard polystyrene conversion. In addition, when it cannot measure without melt | dissolving in trichlorobenzene, the following melt flow rate value was made into the parameter | index of molecular weight.
(3) Melt flow rate value (MFR)
Measured by the method described in JIS K7210: 1999 (polyethylene resin is 190 ° C., 2160 g load).

2. Characteristics of aqueous dispersion of polyolefin resin (1) Appearance The color tone of the aqueous dispersion was evaluated by visual observation.
(2) Average particle diameter of polyolefin resin in aqueous dispersion Using Nikkiso Co., Ltd., Microtrac particle size distribution analyzer UPA150 (MODEL No. 9340, dynamic light scattering method), the aqueous dispersion after 300 mesh filtration The number average particle diameter (nm) and volume average particle diameter (nm) of the polyolefin resin were determined. The refractive index of the resin used for particle diameter calculation was 1.50, and the refractive index of the medium was 1.33.
(3) Solid content concentration An appropriate amount of the aqueous dispersion after 300 mesh filtration was weighed, and this was heated at 150 ° C. until the mass of the residue (solid content) reached a constant weight, and the solid content concentration (mass%) was determined. .
(4) pH
The pH at a temperature of 20 ° C. was measured using a pH meter (Horiba, Ltd., F-52).

3. Characteristics of coating material (1) Appearance The color tone of the coating material was evaluated by visual observation.
(2) Solid content concentration An appropriate amount of the coating material was weighed and heated at 150 ° C. until the mass of the residue (solid content) reached a constant weight to obtain the solid content concentration (% by mass).
(3) pH
The pH at a temperature of 20 ° C. was measured using a pH meter (Horiba, Ltd., F-52).

4). Characteristics of Coating Film and Laminate (1) Deoxygenation capacity The oxygen concentration change in the sample bag was evaluated.
<Laminated body of Examples 1-38, 43-47, Comparative Examples 1-4>
Two samples of 10 cm square are cut out from the obtained laminate, and the filter paper (collectively referred to as “sandwich material”) shown below is sandwiched between the two laminates so that the coated surfaces are in contact with each other. An oxygen material was used. Enclose the oxygen scavenging material in a bag made of a three-layer film of polyester, aluminum, and polyethylene laminated in this order ("Rami Zip" manufactured by AS ONE), remove the air in the bag, and heat seal the insertion slot The bag was sealed. Thereafter, 5 ml of air was injected by a syringe through a septum to prepare a sample bag.
<Laminated body of Examples 39 to 42>
Two 14 cm square samples were cut out from the obtained laminate, and the sandwich material shown below was sandwiched between the two laminates so that the sealant layers were in contact with each other. The four sides were sealed by heat sealing with a seal width of 20 mm. Thereafter, 5 ml of air was injected by a syringe through a septum to prepare a sample bag.
The sample bag prepared above was stored for 5 days in a constant temperature environment of 40 ° C., and then the oxygen concentration in the sample bag was measured using an oxygen concentration meter (CheckPoint O ₂ / CO ₂ manufactured by PBI Dansentor). In addition, the oxygen concentration in the air measured with this apparatus was 21.0%.
Sandwiching material (9.5cm square)
a: Filter paper containing water (manufactured by ADVANTEC, No. 1)
b: Filter paper not containing water (ADVANTEC, No. 1)

(2) Adhesiveness As a base material, linear low density polyethylene (PE) film (manufactured by Tosero Co., Ltd., thickness 50 μm), stretched polypropylene (OPP) film (manufactured by Tosero Corp., thickness 50 μm), stretched polyethylene terephthalate (PET) film (Unitika, thickness 25 μm), stretched polyamide (Ny6) film (Unitika, thickness 25 μm) was used. After applying the deoxidizing paint obtained on each substrate with a wire bar, it was dried at 120 ° C. for 1 minute to obtain a laminate having a coating film having a thickness of 1 μm.
After leaving the obtained laminate at room temperature for 1 day, cellophane tape (TF-12 manufactured by Nichiban Co., Ltd.) was attached to the coating surface, and the degree of peeling when the tape was peeled off at a stretch was visually evaluated according to the following criteria. .
○: No peeling at all.
Δ: A part was peeled off.
X: Most peeled off.

(3) Laminate strength A test piece having a width of 15 mm was taken from the laminate, and a base material (aluminum foil) was removed from the end of the test piece by T-type peeling using a tensile tester (precision universal material testing machine 2020, manufactured by Intesco). ) And the sealant layer were peeled to measure the strength. The measurement was performed in an atmosphere of 20 ° C. and 65% RH at a pulling rate of 200 mm / min.

The following activated carbon was used as the activated carbon particles.
Activated carbon A: “Shirakaba A” manufactured by Nippon Enviro Chemicals, median diameter: 53 μm
Activated carbon F: “Shirakaba FPG-1” manufactured by Nippon Enviro Chemicals, median diameter: 10 μm

The following inorganic materials were used as the inorganic particles.
Silica sol: “Snowtex O” manufactured by Nissan Chemical Co., Ltd., pH: 4, median diameter: 10 nm, solid content concentration: 20% by mass
Alumina sol: “Alumina sol-520” manufactured by Nissan Chemical Co., Ltd., pH: 4, median diameter: 15 nm, solid content concentration: 20% by mass
Silica: “NIPGEL CX-400” manufactured by Tosoh Silica, median diameter: 3.7 μm

The following compounds were used as transition metal compounds.
Iron chloride: “Iron (III) chloride hexahydrate” manufactured by Nacalai Tesque
Iron citrate: “Iron (III) citrate n hydrate” manufactured by Nacalai Tesque
Copper citrate: “Copper citrate (II)” manufactured by Nacalai Tesque

The following resins were used as the acid anhydride-containing copolymer.
LT4403: “Rotada 4403” manufactured by Arkema
LT4700: “Rotada 4700” manufactured by Arkema
TX8030: Arkema “Bondaine TX8030”
HX8290: “Bondaine HX8290” manufactured by Arkema
HX8210: “Bondaine HX8210” manufactured by Arkema
UM2000: “Yumex 2000” manufactured by Sanyo Kasei Co., Ltd.
EA-MAH:
Ethylene, ethyl acrylate, and maleic anhydride were prepared by high-pressure radical polymerization based on the methods described in British Patent No. 2091745, US Pat. No. 4,617,366, and US Pat. No. 4,644,044.
UM1001: "Yumex 1001" manufactured by Sanyo Chemical
PBE-MAH:
It was produced by grafting maleic anhydride onto a propylene-butene-ethylene terpolymer based on the method described in the production examples of Table 2004-104090.
PE-MAH:
Based on the method described in the production examples of Table 2004-104090, maleic anhydride was grafted onto a propylene-ethylene copolymer.
PBE-A-MAH:
Based on the method described in the production examples of Table 2004-104090, lauryl acrylate and maleic anhydride were grafted to a propylene-butene-ethylene terpolymer.

The following resins were used as carboxylic acid-containing polyolefin resins.
EA-A1, EA-A2:
An ethylene-ethyl acrylate copolymer obtained by high-pressure radical polymerization was produced by hydrolysis and thermal degradation based on the method described in JP-A-60-79008.

The following resins were used as aminoacrylate-containing polyolefin resins.
EA:
It was produced by high pressure radical polymerization based on the method described in Japanese Patent Publication No. 53-6194.

  Table 1 summarizes production methods and characteristic values of acid anhydride-containing copolymers, carboxylic acid-containing polyolefin resins, and aminoacrylate-containing polyolefin resins.

(Production of polyolefin resin P-1)
A 1-liter separable flask equipped with a thermometer, a stirrer, a liquid injector, and a Dimroth is charged with 250 g of acid anhydride-containing copolymer “LT4403” and 500 g of toluene, and the stirrer is rotated at 100 prm. Then, the flask was put into an oil bath at 170 ° C. After a few minutes, it was confirmed that toluene was boiled, but the generated steam was refluxed into the flask through the Dimroth. After confirming that the resin was completely dissolved after several minutes, dimethylaminopropylamine [(H ₂ N— (CH ₂ ) ₃ N (CH ₃ ) ₂ ], hereinafter abbreviated as DMAPA) as an amino compound] Was added in an amount of 5 times equivalent mol to the number of moles of the carboxylic anhydride unit of “LT4403”. The resin temperature in the flask after the addition was 115 ° C., and this state was maintained and an imidization reaction was performed. After 30 minutes, the mounting direction of the Dimroth was changed, and the pressure was further gradually reduced, and toluene and unreacted amino compound in the flask were removed by distillation. After confirming that no vapor of toluene and unreacted amino compound was generated from the inside of the flask, the pressure was further released for 10 minutes while maintaining the reduced pressure of 4 kPa (abs), the stirrer was stopped, the flask was taken out of the oil bath, The inner polyolefin resin P-1 was obtained.

(Production of polyolefin resins P-2 to P-13)
Except having changed the kind of acid anhydride containing copolymer, the kind and addition amount of the amino compound as shown in Table 2, the same operation as that of the polyolefin resin P-1 was performed, and the polyolefin resins P-2 to P -13 was obtained. In all cases, the resin temperature during the imidation reaction was in the range of 113 to 118 ° C.

(Production of polyolefin resin P-14)
In a 1 liter separable flask equipped with a thermometer, stirrer and Dimroth, 150 g of carboxylic acid-containing polyolefin resin “EA-A1”, 1 g of paratoluenesulfonic acid as a catalyst, 400 g of xylene, and an amino compound As a sample, DMAPA was charged in an amount equivalent to 1.2 times the number of moles of acrylic acid in the raw resin, and the flask was put into an oil bath at 170 ° C. with the stirrer rotated at 100 prm. After 10 minutes, the resin in the flask was completely dissolved, and the resin temperature was 145 ° C. The reaction was carried out while maintaining this state. After 17 hours, the mounting direction of the Dimroth was changed and the pressure was gradually reduced, and xylene and unreacted amino compound in the flask were removed by distillation. After confirming that the vapors of xylene and unreacted amino compound are no longer generated from the inside of the flask and holding the reduced pressure of 4 kPa (abs) for 10 minutes, release the pressure, stop the stirrer, take out the flask from the oil bath, The polyolefin resin P-14 was recovered. When the infrared absorption spectrum of the polyolefin resin P-14 was measured by the KBr method, absorption near 1650 [cm ⁻¹ ] and 1560 [cm ⁻¹ ] attributed to amide was confirmed.

(Production of polyolefin resin P-15)
Except having used "EA-A2" as carboxylic acid containing polyolefin resin, operation similar to polyolefin resin P-14 was performed and polyolefin resin P-15 was obtained. When the infrared absorption spectrum of the polyolefin resin P-15 was measured by the KBr method, absorption near 1650 [cm ⁻¹ ] and 1560 [cm ⁻¹ ] attributed to amide was confirmed.

  The characteristic values of the obtained polyolefin resins P-1 to P-13 are shown in Table 2, and the characteristic values of the polyolefin resins P-14 and P-15 are shown in Table 3.

(Preparation of aqueous polyolefin resin dispersion E-1)
In a sealable 1 liter pressure-resistant glass container equipped with a stirrer and a heater, 140 g (20 mass%) of “P-1” as a polyolefin resin, formic acid (pKa = 3.75) as an acidic compound, 2.0-fold equivalent moles relative to the number of moles of N-substituted imide units derived from saturated carboxylic anhydride units, 245 g (35% by mass) of n-propanol (hereinafter abbreviated as NPA) as an organic solvent, Distilled water was charged so that the total amount became 700 g, the container was sealed, and the stirring blade was rotated and mixed at a rotational speed of 400 rpm. By stirring, no precipitation of resin particles was observed at the bottom of the container, and it was confirmed that the container was in a floating state. Therefore, the heater was turned on, the temperature inside the container was set to 130 ° C., and the mixture was further stirred for 120 minutes. Thereafter, the heater was turned off and cooled while stirring. Stirring was stopped when the internal temperature became 40 ° C. or lower, and the content in the glass container was filtered with a 300-mesh stainless steel filter to obtain a cationic aqueous dispersion E-1.

(Preparation of aqueous polyolefin resin dispersions E-2 to E-15)
Except for changing the type of polyolefin resin, the type of acidic compound, and the type and amount of the organic solvent as shown in Table 4, the same operations as in E-1 were performed, and the cationic aqueous dispersion E-2 to E-15 was obtained. The pKa of acetic acid as an acidic compound used in the preparation of E-15 is 4.76.

(Preparation of aqueous polyolefin resin dispersion E-16)
In a sealable 1 liter pressure-resistant glass container equipped with a stirrer and a heater, 140 g (20% by mass) of “P-14” as a polyolefin resin and hydrochloric acid as a neutralizing agent in moles of dimethylaminopropylacrylamide units of the resin Distilled water was added so that the total amount of raw materials was 700 g, and the mixture was stirred and mixed at a rotation speed of 400 rpm. By stirring, no precipitation of resin particles was observed at the bottom of the container, and it was confirmed that the container was in a floating state. Therefore, the heater was turned on, the temperature inside the container was set to 130 ° C., and the mixture was further stirred for 120 minutes. Thereafter, the heater was turned off and the mixture was stirred and cooled. Stirring was stopped when the internal temperature became 40 ° C. or lower, and the content in the glass container was filtered with a 300-mesh stainless steel filter to obtain a cationic aqueous dispersion E-16.

(Preparation of aqueous polyolefin resin dispersion E-17)
A cationic aqueous dispersion E-17 was obtained in the same manner as in E-16 except that “P-15” was used as the polyolefin resin.

(Preparation of aqueous polyolefin resin dispersion E-18)
E-A, except that the aminoacrylate-containing polyolefin resin “EA” was used as the resin, and the amount of hydrochloric acid serving as a neutralizing agent was changed to 1.0 times equivalent moles relative to the number of moles of dimethylaminoethyl acrylate in the resin. The same operation as in Example 16 was performed to obtain a cationic aqueous dispersion E-18.

(Preparation of aqueous polyolefin resin dispersion E-19)
In a sealed 1 liter pressure-resistant glass container equipped with a stirrer and a heater, 140 g (20% by mass) of an acid anhydride-containing copolymer “HX-8290” as a resin and triethylamine as an anhydrous maleic resin as a neutralizer Distilled water was charged so that the amount of the acid unit was 2.0 times equivalent mole, 140 g (20% by mass) of NPA as the organic solvent, and the total amount of the raw material was 700 g, the vessel was sealed, The mixture was stirred and mixed at a rotation speed of 400 rpm. By stirring, no precipitation of resin particles was observed at the bottom of the container, and it was confirmed that the container was in a floating state. Therefore, the heater was turned on, the temperature inside the container was set to 130 ° C., and the mixture was further stirred for 120 minutes. Thereafter, the heater was turned off and cooled while stirring. Stirring was stopped when the internal temperature became 40 ° C. or lower, and the content in the glass container was filtered with a 300-mesh stainless steel filter to obtain an anionic aqueous dispersion E-19.

(Preparation of aqueous polyolefin resin dispersion E-20)
An anionic aqueous dispersion E-20 was obtained in the same manner as in E-19 except that the acid anhydride-containing copolymer “EA-MAH” was used as the resin.

  Table 4 shows the characteristic values of the cationic aqueous dispersions obtained in E-1 to E-20.

Example 1
Ascorbic acid was used as an organic oxygen scavenger and added to polyolefin resin aqueous dispersion E-3 so that ascorbic acid was 25 parts by mass with respect to 75 parts by mass of polyolefin resin solids. Further, NPA and distilled water were added to dissolve ascorbic acid, and then activated carbon A was added, mixed and stirred to obtain a deoxygenation coating agent. Each component was mixed to the ratio shown in Table 5.
And as a base material, after using the PET film (the unitika company make, thickness 100micrometer) and applying the deoxidation coating agent obtained by the corona treatment surface with a wire bar, it was dried at 120 degreeC for 1 minute, and thickness A laminate having a 7 μm thick coating film was obtained.
In addition, the sandwiching material a was used at the time of measuring the deoxygenation ability of the obtained laminated body.

Examples 2-15
A deoxygenating coating agent was obtained in the same manner as in Example 1 except that E-1, E-2 and E-4 to E-15 as shown in Table 5 were used as the aqueous polyolefin resin dispersion. Further, a laminate was obtained in the same manner as in Example 1.
In addition, the sandwiching material a was used at the time of measuring the deoxygenation ability of the obtained laminated body.

Examples 16-18
An oxygen scavenger was obtained in the same manner as in Example 1 except that the organic oxygen scavenger ascorbic acid was changed to tannic acid (Example 16), pyrocatechol (Example 17), and pyrogallol (Example 18). Got. Further, a laminate was obtained in the same manner as in Example 1.
In addition, the sandwiching material a was used at the time of measuring the deoxygenation ability of the obtained laminated body.

Example 19
Except having changed the addition amount of activated carbon A so that it might become 33 mass% of total solid, it carried out similarly to Example 1 and obtained the deoxidation coating agent. Further, a laminate was obtained in the same manner as in Example 1.
In addition, the sandwiching material a was used at the time of measuring the deoxygenation ability of the obtained laminated body.

Example 20
Except having changed the activated carbon A into the activated carbon F, it carried out similarly to Example 1 and obtained the deoxidation coating agent. Further, a laminate was obtained in the same manner as in Example 1.
In addition, the sandwiching material a was used at the time of measuring the deoxygenation ability of the obtained laminated body.

Examples 21 and 22
Activated carbon A as a hygroscopic material was changed to iron chloride (Example 21) and iron citrate (Example 22) as transition metal compounds, and each was added in an amount of 5% by mass with respect to ascorbic acid. To obtain a deoxygenation coating agent. Further, a laminate was obtained in the same manner as in Example 1.
In addition, the sandwiching material a was used at the time of measuring the deoxygenation ability of the obtained laminated body.

Example 23
A deoxygenation coating agent was obtained in the same manner as in Example 21 except that E-1 was used as the aqueous polyolefin resin dispersion. Further, a laminate was obtained in the same manner as in Example 1.
In addition, the sandwiching material a was used at the time of measuring the deoxygenation ability of the obtained laminated body.

Example 24
A deoxygenation coating agent was obtained in the same manner as in Example 21 except that ascorbic acid as the organic deoxidation agent was changed to tannic acid. Further, a laminate was obtained in the same manner as in Example 1.
In addition, the sandwiching material a was used at the time of measuring the deoxygenation ability of the obtained laminated body.

Example 25
Except having changed the addition amount of iron chloride so that it might become 3 mass% with respect to ascorbic acid, it carried out similarly to Example 21 and obtained the deoxidation coating agent. Further, a laminate was obtained in the same manner as in Example 1.
In addition, the sandwiching material a was used at the time of measuring the deoxygenation ability of the obtained laminated body.

Examples 26-28
Except that the activated carbon A was changed to alumina sol (Example 26), silica sol (Example 27), and silica (Example 28), the same procedure as in Example 1 was carried out to obtain a deoxygenating coating agent. Further, a laminate was obtained in the same manner as in Example 1.
In addition, the sandwiching material a was used at the time of measuring the deoxygenation ability of the obtained laminated body.

Examples 29-31
Deoxygenation was performed in the same manner as in Example 28 except that 5% by mass of iron chloride (Example 29), iron citrate (Example 30), and copper citrate (Example 31) were added to ascorbic acid. A paint was obtained. Further, a laminate was obtained in the same manner as in Example 1.
In addition, the sandwiching material b was used at the time of measuring the deoxidation ability of the obtained laminated body.

Example 32
A deoxygenating coating agent was obtained in the same manner as in Example 1 except that 5% by mass of iron chloride was added to ascorbic acid. Further, a laminate was obtained in the same manner as in Example 1.
In addition, the sandwiching material b was used at the time of measuring the deoxidation ability of the obtained laminated body.

Example 33
A deoxygenation coating agent was obtained in the same manner as in Example 1 except that the amount of ascorbic acid was changed and ascorbic acid was 90 parts by mass with respect to 10 parts by mass of the solid content of the polyolefin resin. Further, a laminate was obtained in the same manner as in Example 1.
In addition, the sandwiching material a was used at the time of measuring the deoxygenation ability of the obtained laminated body.

Examples 34-36
A laminate was obtained in the same manner as in Example 1 except that the deoxidizing paint obtained in Example 1 was used and the thickness of the coating film was changed to 4 μm, 7 μm, and 15 μm.
Note that the sandwich material b was used in the measurement of the deoxygenation capacity of the obtained laminate.

Example 37
In the measurement of the deoxygenation capacity of the laminate obtained in Example 19, the sandwiching material b was used.

Example 38
In the measurement of the deoxygenation capacity of the laminate obtained in Example 21, sandwiching material b was used.

Example 39
A biaxially stretched polyester resin film ("Embret PET-12" manufactured by Unitika Ltd.) with a thickness of 12 μm is used as the base material, and a two-component curable polyurethane system is applied to the corona-treated surface of the polyester resin film using a gravure coater. A base material having a barrier layer in which an adhesive (made by Toyo Morton Co., Ltd.) is coated and dried so that the coating amount after drying is 5 g / m ^2, and an aluminum foil having a thickness of 7 μm is bonded as a barrier layer. Got.
Subsequently, after applying the deoxidation coating agent obtained in Example 1 to the aluminum foil surface of the barrier layer with a wire bar, it was dried at 120 ° C. for 1 minute to form a coating film having a thickness of 7 μm.
Next, using a laminator equipped with an extruder, LDPE (L211 manufactured by Sumitomo Chemical Co., Ltd.) was melt-extruded as a sealant resin on the coating film to obtain a laminate in which a sealant layer having a thickness of 30 μm was formed.
Note that the sandwich material a was used in the measurement of the deoxygenation ability of the obtained laminate.

Example 40
In the measurement of the deoxygenation capacity of the laminate obtained in Example 39, the sandwiching material b was used.

Example 41
A laminate was obtained in the same manner as in Example 39 except that the deoxidizing paint obtained in Example 16 was used, and the deoxygenating ability was measured.
Note that the sandwich material a was used in the measurement of the deoxygenation ability of the obtained laminate.

Example 42
In the measurement of the deoxygenation capacity of the laminate obtained in Example 41, the sandwiching material b was used.

Examples 43-45
Except that the aqueous polyolefin resin dispersions E-16, E-17, and E-18 were used and the ascorbic acid was 25 parts by mass with respect to 75 parts by mass of the polyolefin resin solid content, the same as in Example 1. A deoxygenating coating was obtained. And the laminated body was obtained like Example 1 and the deoxygenation ability was measured.
Note that the sandwich material a was used in the measurement of the deoxygenation ability of the obtained laminate.

Example 46
Alumina sol was used as the hygroscopic material, and added to the aqueous polyolefin resin dispersion E-3 so that the alumina sol solid content was 30 parts by mass with respect to 70 parts by mass of the polyolefin resin solid content. Furthermore, after adding NPA and distilled water so that the total content of NPA is 20% by mass of the coating and the total solid content is 30% by mass, mixing and stirring are performed to obtain a hygroscopic coating. It was.
And, using a PET film (manufactured by Unitika, thickness of 100 μm) as a base material, the hygroscopic coating obtained on the corona-treated surface was coated with a wire bar, and then dried at 120 ° C. for 1 minute to obtain a thickness. A 5 μm hygroscopic layer was laminated.
A deoxidized coating film was formed on the moisture absorption layer in the same manner as in Example 1 using the deoxidized coating agent used in Example 1 to obtain a laminate.
In addition, the sandwiching material b was used at the time of measuring the deoxidation ability of the obtained laminated body.

Example 47
The laminate obtained in Example 1 was stored in the atmosphere at a temperature of 25 ° C. and a humidity of 20% for 10 days, and then the deoxidizing ability of the laminate was measured.
Note that the sandwich material a was used in the measurement of the deoxygenation ability of the obtained laminate.

Comparative Example 1
Activated carbon A, NPA, and distilled water were added to and mixed with the aqueous polyolefin resin dispersion E-3 to prepare a coating agent. Each component was mixed to the ratio shown in Table 5. And the laminated body was obtained like Example 1 and the deoxygenation ability was measured.
Note that the sandwich material a was used in the measurement of the deoxygenation ability of the obtained laminate.

Comparative Example 2
In Example 21, a coating agent was obtained in the same manner as in Example 21 except that ascorbic acid was not added. And the laminated body was obtained like Example 1 and the deoxygenation ability was measured.
Note that the sandwich material a was used in the measurement of the deoxygenation ability of the obtained laminate.

Comparative Example 3
A coating agent was obtained in the same manner as in Example 32 except that ascorbic acid was not added. And the laminated body was obtained like Example 1 and the deoxygenation ability was measured.
Note that the sandwich material a was used in the measurement of the deoxygenation ability of the obtained laminate.

Comparative Example 4
Except not having mixed the activated carbon A, it carried out like Example 1 and obtained the deoxidation coating agent. Further, a laminate was obtained in the same manner as in Example 1.
In addition, the sandwiching material a was used at the time of measuring the deoxygenation ability of the obtained laminated body.

Comparative Examples 5 and 6
Deoxygenating coating agent as in Example 1 except that polyolefin resin aqueous dispersions E-19 and E-20 were used and ascorbic acid was adjusted to 25 parts by mass with respect to 75 parts by mass of polyolefin resin solids. Although it tried to obtain, it aggregated and the coating agent was not able to be obtained.

  Table 5 shows the characteristic values and evaluations of the coating materials and coating films obtained in Examples 1 to 47 and Comparative Examples 1 to 6, and the laminates.

As is clear from Examples 1 to 33, the coating film and laminate obtained from the deoxidizing paint of the present invention had adhesiveness to various substrates and were excellent in deoxidizing ability.
As apparent from Example 19, when the content of activated carbon as an activator was increased, the deoxygenation ability was improved, but the adhesiveness was slightly lowered. As is clear from Examples 29 to 32, the deoxygenation ability was improved by using a hygroscopic material and a transition metal compound in combination. As is clear from Example 33, the oxygen scavenging ability was improved by increasing the addition amount of the oxygen scavenger, but the adhesiveness was slightly lowered. Further, as is clear from Examples 34 to 36, the deoxygenation ability improved as the coating film thickness increased. Furthermore, as is clear from Examples 29 to 32 and 34 to 38, deoxygenation could be satisfactorily performed without particularly contacting with a sheet containing water. Further, as is clear from Examples 39 to 42, even a laminate having a sealant layer on the coating film had good deoxygenation ability and excellent laminate strength. As is clear from Example 46, by providing the moisture absorbing layer, it was possible to efficiently deoxygenate without particularly contacting with a sheet containing water. As apparent from Example 47, the coating film and laminate of the present invention were excellent in storage stability.
In the coating agents of Examples 43 and 44, the resulting coatings were obtained because the content (mol%) of aminoalkylacrylamide units in the resin was large and the catalyst required for amidation was contained. The film had poor adhesion. In the coating agent of Example 45, since the ethylene-aminoalkyl acrylate copolymer was used, the obtained coating film had poor adhesiveness.
On the other hand, since the coating materials of Comparative Examples 1 to 3 did not contain an oxygen scavenger, the resulting laminates did not exhibit oxygen scavenging ability. Since the coating agent of Comparative Example 4 did not contain a hygroscopic material and / or a transition metal compound, it had poor oxygen scavenging properties. In Comparative Examples 5 and 6, since an anionic aqueous dispersion comprising a polyolefin resin, a basic compound, and an aqueous medium was used as the aqueous polyolefin resin dispersion, the aqueous dispersion agglomerated when ascorbic acid was added, Couldn't get.

Claims (6)

  An oxygen scavenger-containing coating film comprising an organic oxygen scavenger, a polyolefin resin containing an olefinic hydrocarbon unit and an amino group-containing unit, and a hygroscopic material and / or a transition metal compound. . The content of units having an amino group is, for all the structural units 100 mole% constituting the polyolefin resin, 0.1 mol% or more, deoxygenation of claim 1, wherein less than 10 mole% Agent-containing coating. A laminate comprising the substrate and the oxygen-absorbing agent-containing coating film according to claim 1 or 2 laminated thereon. A laminate in which a sealant layer is laminated on the oxygen scavenger-containing coating film of the laminate according to claim 3 . The laminate according to claim 3 or 4, wherein the substrate has a barrier property. The laminate according to any one of claims 3 to 5 , wherein a moisture absorbing layer is laminated on at least one of the upper and lower sides of the oxygen scavenger-containing coating.