Gas-barrier film

The present invention relates to a novel gas barrier film.

Conventionally, as a food film packaging material, from the viewpoint of preventing deterioration of flavor and freshness, gas barrier properties such as oxygen blocking property, carbon dioxide gas blocking property, and water vapor blocking property, ultraviolet ray blocking property, aroma retaining property, etc. are required. From the viewpoint of displayability at the store, high transparency that allows the contents to be seen is also required.

Conventionally, as a gas barrier film packaging material, a film in which a polyvinylidene chloride resin layer is coated and laminated as a gas barrier layer on the surface of a plastic film has been generally used. However, in recent years, the development of a non-chlorine-based gas barrier film packaging material has been strongly desired due to the problem of generation of hydrogen chloride gas, dioxin, etc. at the time of incineration.

As a non-chlorine-based gas barrier film packaging material, for example, there is a film using a gas barrier resin such as an ethylene-vinyl alcohol copolymer or polyvinyl alcohol, but the gas barrier property deteriorates under high humidity. There was a problem that the applications that could be used were limited.

<p> An object of the present invention is to obtain a novel gas barrier film having excellent gas barrier properties such as oxygen blocking property, carbon dioxide gas blocking property, and water vapor blocking property, and also having excellent ultraviolet blocking property, aroma retention property, transparency and the like. To provide.</p><p> Other objects and features of the present invention will be clarified by the following description.</p>

<p> The present invention provides the following novel gas barrier film.</p><p> 1. A gas barrier film formed by laminating a titanium oxide film layer (B) on one or both sides of a plastic film layer (A).</p><p> 2. The titanium oxide film layer (B) peroxidizes at least one titanium compound selected from a hydrolyzable titanium compound, a low condensate of a hydrolyzable titanium compound, and a low condensate of titanium hydroxide and titanium hydroxide. A coating agent for forming a titanium oxide film, which is a titanium-containing aqueous liquid (a) obtained by mixing with hydrogen water, is applied onto the plastic film layer (A) and dried at a temperature of 200 ° C. or lower for laminating. The film according to item 1 above.</p><p> 3. The film according to Item 2 above, wherein the titanium-containing aqueous solution (a) is a peroxotitanic acid aqueous solution obtained by mixing a hydrolyzable titanium compound and / or a low condensate thereof with a hydrogen peroxide solution.</p><p> 4. Hydrolyzable titanium compound is a general formula Ti (OR) 4 (1) The film according to Item 3 above, which is a tetraalkoxytitanium represented by (in the formula, R is the same or different and represents an alkyl group having 1 to 5 carbon atoms).</p><p> 5. The low condensate of hydrolyzable titanium compound is a general formula Ti (OR) 4 (1) (In the formula, R represents the same or different alkyl group having 1 to 5 carbon atoms.) The above item is a compound having a degree of condensation of 2 to 30 formed by condensation reaction of tetraalkoxytitanium represented by each other. The film described in 3.</p><p> 6. The mixing ratio of the hydrolyzable titanium compound and / or its low condensate and the hydrogen peroxide solution is in the range of 0.1 to 100 parts by weight in terms of hydrogen peroxide for the latter compared to 10 parts by weight for the former. The film according to Item 3.</p><p> 7. The above item, wherein the titanium-containing aqueous solution (a) is a peroxotitanic acid aqueous solution obtained by mixing a hydrolyzable titanium compound and / or a low condensate thereof with a hydrogen peroxide solution in the presence of a titanium oxide sol. The film described in 3.</p><p> 8. The film according to item 7 above, wherein the titanium oxide sol is an aqueous dispersion of anatase-type titanium oxide.</p><p> 9. The film according to Item 7, wherein the amount of the titanium oxide sol used is 0.01 to 10 parts by weight in terms of solid content with respect to 1 part by weight of the hydrolyzable titanium compound and / or its low condensate.</p><p> 10. The titanium oxide film layer (B) peroxidizes at least one titanium compound selected from a hydrolyzable titanium compound, a low condensate of a hydrolyzable titanium compound, and a low condensate of titanium hydroxide and titanium hydroxide. A coating agent for forming a titanium oxide film containing a titanium-containing aqueous solution (a) obtained by mixing with hydrogen water, an organic basic compound (b), and an aqueous organic polymer compound (c) stable at a pH of 10 or less is used as a plastic. Item 2. The film according to Item 1 above, which is laminated by applying it on the film layer (A) and drying it at a temperature of 200 ° C. or lower.</p><p> 11. The film according to Item 10 above, wherein the titanium-containing aqueous solution (a) is a peroxotitanic acid aqueous solution obtained by mixing a hydrolyzable titanium compound and / or a low condensate thereof with a hydrogen peroxide solution.</p><p> 12. Hydrolyzable titanium compound is a general formula Ti (OR) 4 (1) The film according to Item 11 above, which is a tetraalkoxytitanium represented by (in the formula, R represents an alkyl group having 1 to 5 carbon atoms, which is the same or different).</p><p> 13. The low condensate of hydrolyzable titanium compound is a general formula Ti (OR) 4 (1) (In the formula, R represents the same or different alkyl group having 1 to 5 carbon atoms.) The above item is a compound having a degree of condensation of 2 to 30 formed by condensation reaction of tetraalkoxytitanium represented by each other. The film described in 11.</p><p> 14. The mixing ratio of the hydrolyzable titanium compound and / or its low condensate and the hydrogen peroxide solution is in the range of 0.1 to 100 parts by weight in terms of hydrogen peroxide for the latter compared to 10 parts by weight for the former. Item 10. The film according to Item 11.</p><p> 15. Titanium-containing aqueous solution (a) is a peroxotitanic acid aqueous solution obtained by mixing a hydrolyzable titanium compound and / or a low condensate thereof with a hydrogen peroxide solution in the presence of a titanium oxide sol. The film described in 11.</p><p> 16. The film according to Item 15, wherein the titanium oxide sol is an aqueous dispersion of anatase-type titanium oxide.</p><p> 17. The film according to Item 15, wherein the amount of the titanium oxide sol used is 0.01 to 10 parts by weight in terms of solid content with respect to 1 part by weight of the hydrolyzable titanium compound and / or its low condensate.</p><p> 18. The film according to Item 10 above, wherein the organic basic compound (b) has a boiling point of 300 ° C or less.</p><p> 19. The film according to Item 10 above, wherein the amount of the organic basic compound (b) used is 0.001 to 10 parts by weight with respect to 100 parts by weight of the solid content of the titanium-containing aqueous liquid (a).</p><p> 20. Aqueous organic polymer compound (c) is epoxy resin, phenol resin, acrylic resin, urethane resin, polyester resin, polyvinyl alcohol resin, polyoxyalkylene chain-containing resin, olefin-polymerizable unsaturated Item 5. The film according to Item 10, which is at least one resin selected from the group consisting of carboxylic acid copolymerization system resins.</p><p> 21. The film according to Item 10 above, wherein the amount of the aqueous organic polymer compound (c) used is 0.1 to 200 parts by weight with respect to 100 parts by weight of the solid content of the titanium-containing aqueous liquid (a).</p><p> 22. The film according to Item 10 above, wherein the coating agent for forming a titanium oxide film is an aqueous coating agent having a pH of 2 to 10.</p><p> 23. The film according to Item 1 above, wherein a part or all of titanium oxide constituting the titanium oxide film layer (B) is amorphous titanium oxide.</p><p> 24. The film according to item 1 above, wherein the plastic film layer (A) is a plastic film layer for food packaging.</p><p> 25. The film according to item 1 or 24 above, wherein the plastic film layer (A) is a polypropylene film layer.</p><p> 26. The film according to Item 1 above, wherein the thickness of the plastic film layer (A) is 5 to 100 μm.</p><p> 27. The film according to Item 1 above, wherein the titanium oxide film layer (B) has a thickness of 0.001 to 10 μm.</p><p> The present inventor has conducted extensive research to achieve the above object. As a result, by laminating the titanium oxide film layer (B) as a gas barrier layer on one side or both sides of the plastic film layer (A), gas barrier properties such as oxygen blocking property, carbon dioxide gas blocking property, and water vapor blocking property are obtained. It has been found that a new gas barrier film having excellent UV blocking property, fragrance retaining property, transparency and the like can be obtained. Further, the titanium oxide film layer (B) is a coating agent for forming a titanium oxide film, which is the specific aqueous solution (a), or the aqueous solution (a), which is organically basic, on the plastic film layer (A). It has been found that a coating agent for forming a titanium oxide film containing the compound (b) and the aqueous organic polymer compound (c) can be suitably formed by coating and drying.</p><p> The present invention has been completed based on such new findings.</p><p><u style="single">Plastic film layer (A)</u> The plastic film layer (A) in the film of the present invention is known as long as it is a plastic film base material used for packaging or the like and can fix and hold the titanium oxide film layer (B). Any of these can be used.</p><p> Examples of the material of the film layer (A) include polyethylene, polypropylene, polyisobutylene, polybutadiene, polyvinyl acetate, polyvinyl chloride, polyethylene terephthalate (PET), nylon, polystyrene, polyurethane, polycarbonate (PC), and polyvinyl alcohol (). PVA), ethylene-vinyl alcohol copolymer, polyacetal, AS resin, ABS resin, melamine resin, acrylic resin, epoxy resin, polyester resin and other thermoplastics can be mentioned. Among these, polypropylene and polyethylene terephthalate are particularly preferable from the viewpoint of processability, safety and hygiene, etc. when used for food.</p><p> Further, the plastic film layer (A) may contain an ultraviolet absorber, a filler, a heat stabilizer, a colorant and the like, if necessary. Further, the surface of the film layer (A) may be subjected to surface treatment such as corona discharge treatment. Further, the surface of the film layer (A) may be colored or patterned with ink or paint.</p><p> The thickness of the plastic film layer (A) is usually in the range of about 5 to 100 μm, preferably 20 to 80 μm.</p><p><u style="single">Titanium oxide film layer (B)</u> In the film of the present invention, the titanium oxide film layer (B) provided on the surface of the plastic film layer (A) exhibits excellent gas barrier properties, ultraviolet blocking properties, aroma retaining properties, etc., and is also excellent in transparency. ..</p><p> The titanium oxide film layer (B) is a coating agent for forming a titanium oxide film, which is the specific aqueous solution (a), or the aqueous solution (a), which is organically basic, on one side or both sides of the plastic film layer (A). A coating agent for forming a titanium oxide film containing the compound (b) and the aqueous organic polymer compound (c) can be suitably laminated by applying and drying.</p><p> At least one titanium compound selected from a hydrolyzable titanium compound, a low condensate of a hydrolyzable titanium compound, and a low condensate of titanium hydroxide and titanium hydroxide, which is a coating agent for forming a titanium oxide film, is hydrogenated. As the titanium-containing aqueous solution (a) obtained by mixing with water, a known one can be appropriately selected and used.</p><p> The hydrolyzable titanium compound is a titanium compound having a hydrolyzable group directly bonded to a titanium atom, and produces titanium hydroxide by reacting with water such as water and water vapor. Further, in the hydrolyzable titanium compound, it does not matter whether all the groups bonded to the titanium atom are hydrolyzable groups or a part of the hydrolyzable groups is a hydrolyzed hydroxyl group. ..</p><p> The hydrolyzable group is not particularly limited as long as it produces a hydroxyl group by reacting with water, and examples thereof include a lower alkoxyl group and a group forming a salt with a titanium atom. Examples of the group forming a salt with a titanium atom include a halogen atom (chlorine and the like), a hydrogen atom, a sulfate ion and the like.</p><p> Examples of the hydrolyzable titanium compound containing a lower alkoxyl group as the hydrolyzable group include tetraalkoxytitanium and the like.</p><p> Typical examples of the hydrolyzable titanium compound having a group forming a salt with titanium as the hydrolyzable group include titanium chloride and titanium sulfate.</p><p> The low condensate of the hydrolyzable titanium compound is a low condensate of the above hydrolyzable titanium compounds. In the low condensate, it does not matter whether all the groups bonded to the titanium atom are hydrolyzable groups or a part of the hydrolyzable groups are hydrolyzed hydroxyl groups.</p><p> As the low condensate of titanium hydroxide, for example, orthotitanic acid (titanium hydroxide gel) obtained by reacting an aqueous solution of titanium chloride, titanium sulfate or the like with an alkaline aqueous solution of ammonia, caustic soda or the like can be used.</p><p> A compound having a degree of condensation of 2 to 30 can be used in the low condensation product of the hydrolyzable titanium compound or the low condensation product of titanium hydroxide, and it is particularly preferable to use a compound having a degree of condensation in the range of 2 to 10.</p><p> As the aqueous solution (a), a conventionally known aqueous solution can be used without particular limitation as long as it is a titanium-containing aqueous solution obtained by reacting the titanium compound with a hydrogen peroxide solution. Specifically, the following can be used.</p><p> (1) A peroxotitanic acid aqueous solution obtained by adding a hydrogen peroxide solution to a titanium hydroxide-containing gel or sol described in JP-A-63-35419 and JP-A No. 1-224220.</p><p> (2) It is called orthotitanic acid by reacting an aqueous solution of titanium chloride, titanium sulfate or the like described in JP-A-9-71418 and JP-A-10-67516 with an alkaline aqueous solution such as ammonia or caustic soda. An aqueous solution for forming a titanium oxide film, which is a yellow transparent viscous liquid obtained by precipitating a titanium hydroxide gel, then separating the titanium hydroxide gel by decantation, washing with water, and adding hydrogen peroxide solution to the separation.</p><p> (3) Peroxotitanium hydrate is added to an aqueous solution of an inorganic titanium compound such as titanium chloride or titanium sulfate described in JP-A-2000-247638 and JP-A-2000-247639 by adding hydrogen peroxide solution. A solution obtained by adding a basic substance to the formed solution is left to stand or heated to form a precipitate of a peroxotitanium hydrate polymer, and hydrogen peroxide is allowed to act after removing dissolved components other than water. An aqueous solution for forming a titanium oxide film obtained.</p><p> As the titanium-containing aqueous solution (a), it is preferable to use a peroxotitanic acid aqueous solution (a1) obtained by mixing a hydrolyzable titanium compound and / or a low condensate thereof with a hydrogen peroxide solution.</p><p> The titanium compound has a particularly general formula. Ti (OR)₄ (1) (In the formula, R represents the same or different alkyl group having 1 to 5 carbon atoms.) Tetraalkoxytitanium represented by is preferable. Examples of the alkyl group having 1 to 5 carbon atoms represented by R include a methyl group, an ethyl group, an n-propyl group, an iso-propyl group, an n-butyl group, an iso-butyl group, a sec-butyl group, and a tert- Butyl groups and the like can be mentioned.</p><p> Further, as the low condensation product of the titanium compound, it is preferable to use a compound having a condensation degree of 2 to 30 obtained by subjecting the compounds of the general formula (1) to a condensation reaction with each other, and a compound having a condensation degree of 2 to 10 is used. It is more preferable to use it.</p><p> The mixing ratio of the hydrolyzable titanium compound of the general formula (1) and / or its low condensate (hereinafter, these are simply abbreviated as "hydrolyzable titanium compound (I)") and the hydrogen peroxide solution is Compared to the former 10 parts by weight, the latter is preferably in the range of 0.1 to 100 parts by weight, particularly 1 to 20 parts by weight in terms of hydrogen peroxide. If the latter is less than 0.1 parts by weight in terms of hydrogen peroxide, the formation of peroxotitanic acid becomes insufficient and a cloudy precipitate occurs, which is not preferable. On the other hand, if it exceeds 100 parts by weight, unreacted hydrogen peroxide tends to remain and dangerous active oxygen is released during storage, which is not preferable.</p><p> The hydrogen peroxide concentration of the hydrogen peroxide solution is not particularly limited, but is preferably in the range of 3 to 40% by weight from the viewpoint of ease of handling.</p><p> In the peroxotitanic acid aqueous solution, the hydrolyzable titanium compound (I) is usually mixed with hydrogen peroxide solution under stirring for about 10 minutes to 20 hours at a temperature of about 1 to 70 ° C. Can be prepared by. At the time of this mixing, if necessary, a water-soluble solvent such as methanol, ethanol, n-propanol, iso-isopropanol, ethylene glycol monobutyl ether, propylene glycol monomethyl ether and the like can also be used.</p><p> In the peroxotitanic acid aqueous solution (a1), the hydrolyzable titanium compound (I) is mixed with the hydrogen peroxide solution, so that the hydrolyzable titanium compound is hydrolyzed with water to produce a hydroxyl group-containing titanium compound, and then the hydrolyzable titanium compound is produced. It is presumed that hydrogen peroxide is immediately coordinated with this hydroxyl group-containing titanium compound to form peroxotitanic acid. This peroxotitanic acid aqueous solution is highly stable at room temperature and can withstand long-term storage.</p><p> Further, the peroxotitanic acid aqueous solution (a2) obtained by mixing the hydrolyzable titanium compound (I) with the hydrogen peroxide solution in the presence of the titanium oxide sol has the storage stability of the aqueous solution and the obtained titanium oxide film. It is preferable because it has improved UV blocking property, corrosion resistance, and the like. The reason is that in the preparation of the aqueous solution, the hydrolyzable titanium compound (I) is adsorbed on the titanium oxide sol particles, and the adsorbed hydrolyzable titanium compound (I) undergoes a condensation reaction with the hydroxyl groups generated on the surface of the particles. The hydrolyzable titanium compound itself is also condensed and polymerized, and then mixed with a hydrogen peroxide solution to stabilize the obtained aqueous solution and gel it during storage. It is presumed that thickening is significantly prevented.</p><p> The titanium oxide sol is a sol in which amorphous titanium oxide fine particles and anatase type titanium oxide fine particles are dispersed in water. As the titanium oxide sol, an anatase-type aqueous dispersion of titanium oxide is preferable from the viewpoint of ultraviolet blocking property. The titanium oxide sol may contain, if necessary, an aqueous organic solvent such as an alcohol-based solvent or an alcohol ether-based solvent in addition to water.</p><p> As the titanium oxide sol, conventionally known ones can be used. As the titanium oxide sol, for example, atypical titanium oxide fine particles in which titanium oxide aggregates are dispersed in water, or anatase-type titanium oxide fine particles obtained by firing the titanium oxide aggregates and dispersed in water are used. Can be done. Amorphous titanium oxide can be converted into anatase-type titanium oxide by firing at least at a temperature equal to or higher than the crystallization temperature of anatase, usually at a temperature of 200 ° C. or higher. Examples of the titanium oxide aggregate include (1) one obtained by hydrolyzing an inorganic titanium compound such as titanium sulfate and titanyl sulfate, and (2) one obtained by hydrolyzing an organic titanium compound such as titanium alkoxide. , (3) Examples thereof include those obtained by hydrolyzing or neutralizing a titanium halide solution such as titanium tetrachloride.</p><p> Examples of commercially available titanium oxide sol products include "TKS-201" (manufactured by Teika Co., Ltd., trade name, aqueous sol of anatase-type titanium oxide fine particles having an average particle diameter of 6 nm) and "TKS-203" (Taika Co., Ltd.). ), Product name, aqueous sol of anatase-type titanium oxide fine particles with an average particle diameter of 6 nm), "TA-15" (manufactured by Nissan Chemical Co., Ltd., product name, aqueous sol of anatase-type titanium oxide fine particles), "STS- 11 (manufactured by Ishihara Sangyo Co., Ltd., trade name, aqueous sol of anatase-type titanium oxide fine particles) and the like.</p><p> The amount of titanium oxide sol to be present when mixing the hydrolyzable titanium compound (I) and the hydrogen peroxide solution is usually 0.01 to 1 part by weight of the hydrolyzable titanium compound (I) in terms of solid content. It is in the range of 10 parts by weight, preferably 0.1 to 8 parts by weight. If the amount of titanium oxide sol used is less than 0.01 parts by weight, the effect of adding titanium oxide sol, such as improvement of storage stability of the coating agent and UV blocking property of the obtained titanium oxide film, cannot be obtained, while if it exceeds 10 parts by weight, the effect of adding titanium oxide sol cannot be obtained. It is not preferable because the film-forming property of the coating agent is inferior.</p><p> The titanium-containing aqueous solution (a) is a peroxotitanic acid aqueous solution obtained by mixing the hydrolyzable titanium compound (I) with a hydrogen peroxide solution in the presence of a titanium oxide sol, if necessary, at 80 ° C. It can also be used after being heat-treated or autoclaved at the above temperature to prepare a dispersion of titanium oxide fine particles having an average particle size of 10 nm or less. The appearance of this dispersion is usually translucent.</p><p> If the temperature of the heat treatment or the autoclave treatment is less than 80 ° C, the crystallization of titanium oxide does not proceed sufficiently. The titanium oxide fine particles obtained by the above treatment have a particle size of 10 nm or less, preferably in the range of 1 nm to 6 nm. If the particle size is larger than 10 nm, the film-forming property is lowered, and cracks occur when the film thickness is 1 μm or more, which is not preferable.</p><p> The titanium-containing aqueous solution (a), which is a coating agent for forming a titanium oxide film, is coated on a plastic film, heated at a temperature of 200 ° C. or lower, and dried to obtain dense titanium oxide having excellent adhesion. A film can be formed. The lower limit of the drying temperature is not particularly limited. For example, it may be dried at room temperature.</p><p> When the titanium-containing aqueous liquid (a) is the aqueous liquid (a1), an amorphous titanium oxide film containing a small amount of hydroxyl groups is usually formed under the above drying conditions. The amorphous titanium oxide film has an advantage of being more excellent in gas barrier property, transparency and the like. In the case of the titanium-containing aqueous solution (a2), an anatase-type titanium oxide film containing a small amount of hydroxyl groups is usually formed under the above-mentioned drying conditions.</p><p> By using a coating agent containing a titanium-containing aqueous solution (a), an organic basic compound (b), and an aqueous organic polymer compound (c) stable at pH 10 or less as a coating agent for forming a titanium oxide film, a plastic film is used. It is possible to obtain a gas barrier film having further improved adhesion to the layer (A) and less deterioration of gas barrier property due to friction, bending, etc. during processing, distribution, and the like.</p><p> When the organic basic compound (b) and the aqueous organic polymer compound (c) are used in combination, the same titanium-containing aqueous liquid (a) as described above can be used.</p><p> As the organic basic compound (b), any organic basic compound having a boiling point of 300 ° C. or lower that can be neutralized can be used without limitation. Desirable ones include, in particular, ammonia, dimethylethanolamine, 2-amino-2-methyl-1-propanol, triethylamine, morpholine and the like.</p><p> The amount of the organic basic compound (b) used is 0.001 to 10 parts by weight, preferably 0.005 to 5 parts by weight, based on 100 parts by weight (solid content) of the titanium-containing aqueous liquid (a). Even if the organic basic compound (b) is used in an amount less than the above range, its effect is insufficient. When the organic basic compound (b) is used beyond the above range, the ratio of the organic basic compound (b) remaining in the formed film becomes large, the film-forming property is lowered, and the gas barrier property is obtained. , Performance such as anticorrosion tends to deteriorate.</p><p> As the aqueous organic polymer compound (c), known compounds can be used without limitation as long as they are in a stable state after being dissolved or dispersed in water at a pH of 10 or less.</p><p> Further, as the aqueous organic polymer compound (c), a compound having the form of an aqueous solution, an aqueous dispersion or an emulsion can be used. As a method for water-solubilizing, dispersing or emulsifying the organic polymer compound in water, a known method can be used.</p><p> Specific examples of the aqueous organic polymer compound (c) include at least one functional group (for example, a hydroxyl group, a carboxyl group, an amino group, an imino group, a sulfide group, a phosphine group, etc.) that can be water-soluble or water-dispersible by itself. Species), those containing some or all of the functional groups of the compound, and the like can be used. In this case, if the aqueous organic polymer compound (c) is an acidic resin such as a carboxyl group-containing resin, an amine compound such as ethanolamine or triethylamine; aqueous ammonia; lithium hydroxide, sodium hydroxide, or hydroxide It is neutralized with alkali metal hydroxides such as potassium, and if it is a basic resin such as an amino group-containing resin, it is neutralized with fatty acids such as acetic acid and lactic acid; and mineral acids such as phosphoric acid.</p><p> Examples of the aqueous organic polymer compound (c) include epoxy resins, phenol resins, acrylic resins, urethane resins, polyester resins, polyvinyl alcohol resins, polyoxyalkylene chain-containing resins, and olefin-polymerizable resins. Examples thereof include unsaturated carboxylic acid copolymer resin, nylon resin, polyglycerin, carboxymethyl cellulose, hydroxymethyl cellulose, hydroxyethyl cellulose and the like.</p><p> Among the above-mentioned aqueous organic polymer compounds (c), preferable ones are epoxy-based resin, phenol-based resin, acrylic-based resin, urethane-based resin, polyester-based resin, polyvinyl alcohol-based resin, polyoxyalkylene chain-containing resin, and olefin. -A polymerizable unsaturated carboxylic acid copolymer resin and the like can be mentioned. Particularly preferable ones include epoxy resins, polyester resins, urethane resins, phenol resins and the like.</p><p> As the epoxy resin, a cationic epoxy resin obtained by adding an amine to the epoxy resin; a modified epoxy resin such as an acrylic modified epoxy resin or a urethane modified epoxy resin can be preferably used. Examples of the cationic epoxy resin include an addition of an epoxy compound and a primary mono- or polyamine, a secondary mono- or polyamine, a primary or secondary mixed polyamine, and the like (see, for example, US Pat. No. 3,984,299); Additives of epoxy compounds to secondary mono- or polyamines with ketiminated primary amino groups (see, eg, US Pat. No. 4017438); hydroxyl compounds with epoxy compounds and ketiminated primary amino groups. Examples thereof include an etherification reaction product with (see, for example, Japanese Patent Application Laid-Open No. 59-43013).</p><p> As the epoxy compound, those having a number average molecular weight in the range of 400 to 4,000, particularly 800 to 2,000, and an epoxy equivalent in the range of 190 to 2,000, particularly 400 to 1,000 are suitable. Such epoxy compounds can be obtained, for example, by reacting polyphenol compounds with epichlorohydrin. Examples of the polyphenol compound include bis (4-hydroxyphenyl) -2,2-propane, 4,4-dihydroxybenzophenone, bis (4-hydroxyphenyl) -1,1-ethane, and bis (4-hydroxyphenyl)-. 1,1-isobutane, bis (4-hydroxy-tert-butylphenyl) -2,2-propane, bis (2-hydroxynaphthyl) methane, 1,5-dihydroxynaphthalene, bis (2,4-dihydroxyphenyl) methane , Tetra (4-hydroxyphenyl) -1,1,2,2-ethane, 4,4-dihydroxydiphenylsulfone, phenol novolac, cresol novolac and the like.</p><p> As the phenolic resin, a water-solubilized polymer compound obtained by heating, adding and condensing a phenol component and formaldehyde in the presence of a reaction catalyst can be preferably used. As the above-mentioned phenol component as a starting material, a bifunctional phenol compound, a trifunctional phenol compound, a phenol compound having four or more functionalities, or the like can be used. Bifunctional phenolic compounds include o-cresol, p-cresol, p-tert-butylphenol, p-ethylphenol, 2,3-xylenol, 2,5-xylenol, and trifunctional phenolic compounds include phenol. Examples of the tetrafunctional phenol compound such as m-cresol, m-ethylphenol, 3,5-xylenol, and m-methoxyphenol include bisphenol A and bisphenol F. These phenol compounds can be used alone or in admixture of two or more.</p><p> Examples of the acrylic resin include homopolymers or copolymers of monomers having hydrophilic groups such as carboxyl groups, amino groups, and hydroxyl groups, and monomers having hydrophilic groups and other copolymerizable monomers. Examples include the copolymer of. These resins are obtained by emulsion polymerization, suspension polymerization or solution polymerization, and if necessary, neutralizing and water-forming. Further, the obtained resin may be further modified if necessary.</p><p> Examples of the carboxyl group-containing monomer include acrylic acid, methacrylic acid, maleic acid, maleic anhydride, crotonic acid, and itaconic acid.</p><p> Examples of the nitrogen-containing monomer include nitrogen-containing alkyl (meth) acrylates such as N, N-dimethylaminoethyl (meth) acrylate, N, N-diethylaminoethyl (meth) acrylate, and Nt-butylaminoethyl (meth) acrylate; Acrylate, methacrylicamide, N-methyl (meth) acrylamide, N-ethyl (meth) acrylamide, N-methylol (meth) acrylamide, N-methoxymethyl (meth) acrylamide, N-butoxymethyl (meth) acrylamide, N, N -Polymer amides such as dimethyl (meth) acrylamide, N, N-dimethylaminopropyl (meth) acrylamide, N, N-dimethylaminoethyl (meth) acrylamide; 2-vinylpyridine, 1-vinyl-2-pyrrolidone, Aromatic nitrogen-containing monomers such as 4-vinylpyridine; allylamine and the like.</p><p> Examples of the hydroxyl group-containing monomer include 2-hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate, 2,3-dihydroxybutyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate and polyethylene glycol mono (meth). Monoesterates of polyhydric alcohol and acrylic acid or methacrylic acid such as acrylate; compounds obtained by ring-opening polymerization of ε-caprolactone on the monoesteride of polyhydric alcohol and acrylic acid or methacrylic acid can be mentioned.</p><p> Other copolymerizable monomers include, for example, methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, isopropyl (meth) acrylate, n-butyl (meth) acrylate, and isobutyl (meth). Acrylate, tert-butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, n-octyl (meth) acrylate, lauryl (meth) acrylate, tridecyl (meth) acrylate, octadecyl (meth) acrylate, isostearyl (meth) acrylate Alkyl (meth) acrylate having 1 to 24 carbon atoms such as styrene, vinyl acetate and the like. These compounds can be used alone or in combination of two or more.</p><p> In addition, in this specification, "(meth) acrylate" means acrylate or methacrylate.</p><p> The urethane-based resin is a chain of a polyurethane resin obtained from a polyol such as a polyester polyol or a polyether polyol and a diisocyanate, which is a low molecular weight compound having two or more active hydrogens such as a diol and a diamine, if necessary. Those in which the chain is extended in the presence of an extender and stably dispersed or dissolved in water can be preferably used. Examples of such urethane-based resins include Tokukosho 42-24192, Tokukousho 42-24194, Tokukousho 42-5118, Tokukousho 49-986, Tokukousho 49-33104, and Tokukousho 50-15027. , Public Publication No. 53-29175, etc., can be widely used.</p><p> As a method for stably dispersing or dissolving the polyurethane resin in water, for example, the following method can be used.</p><p> (1) A method in which hydrophilicity is imparted by introducing an ionic group such as a hydroxyl group, an amino group, or a carboxyl group into the side chain or terminal of a polyurethane resin, and the polyurethane resin is dispersed or dissolved in water by self-emulsification.</p><p> (2) A method in which a polyurethane resin in which the reaction is completed or a polyurethane resin in which terminal isocyanate groups are blocked with a blocking agent is forcibly dispersed in water by using an emulsifier and a mechanical shearing force. Examples of this blocking agent include oximes, alcohols, phenols, mercaptans, amines, sodium bisulfite and the like.</p><p> (3) A method in which a polyurethane resin having a terminal isocyanate group is mixed with water, an emulsifier and a chain extender, and dispersion and high molecular weight are simultaneously performed by using a mechanical shearing force.</p><p> (4) A method of dispersing or dissolving a polyurethane resin obtained by using a water-soluble polyol such as polyethylene glycol as a raw material polyol of a polyurethane resin in water.</p><p> The aqueous resin obtained by the above-mentioned method for dispersing or dissolving a polyurethane resin can be used alone or in combination of two or more.</p><p> Examples of the diisocyanate that can be used for synthesizing the polyurethane resin include aromatic, alicyclic and aliphatic diisocyanates. Specifically, for example, hexamethylene diisocyanate, tetramethylene diisocyanate, 3,3 ́-dimethoxy-4,4 ́-biphenylenediocyanate, p-xylylene diisocyanate, m-xylylene diisocyanate, 1,3- (diisocyanato). Methyl) cyclohexanone, 1,4- (diisocyanatomethyl) cyclohexanone, 4,4 ́-diisocyanatocyclohexanone, 4,4 ́-methylenebis (cyclohexylisocyanate), isophorone diisocyanate, 2,4-tolylene diisocyanate, 2, 6-Tolylene diisocyanate, p-phenylenediisocyanate, diphenylmethane diisocyanate, m-phenylenediisocyanate, 2,4-naphthalenediisocyanate, 3,3 ́-dimethyl-4,4 ́-biphenylenediisocyanate, 4,4 ́-Biphenylene isocyanate and the like can be mentioned. Of these, 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, hexamethylene diisocyanate, and isophorone diisocyanate are particularly preferable.</p><p> Examples of commercially available polyurethane-based resins include "Hydran HW-330", "Hydran HW-340", "Hydran HW-350" (all manufactured by Dainippon Ink and Chemicals Co., Ltd., trade name), and "Hydran HW-330". Examples include "Superflex 100", "Superflex 150", and "Superflex F-3438D" (all manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd., trade name).</p><p> The polyvinyl alcohol-based resin is preferably a polyvinyl alcohol having a saponification degree of 87% or more, and particularly preferably a so-called completely saponified polyvinyl alcohol having a saponification degree of 98% or more. Further, it is preferable that the number average molecular weight is in the range of 3,000 to 100,000.</p><p> As the polyoxyalkylene chain-containing resin, one having a polyoxyethylene chain or a polyoxypropylene chain can be preferably used. For example, polyethylene glycol, polypropylene glycol, polyoxyethylene chain and polyoxypropylene chain are formed in a block shape. Examples thereof include bound blocked polyoxyalkylene glycol.</p><p> The olefin-polymerizable unsaturated carboxylic acid copolymerization system resin includes a copolymer of an olefin such as ethylene and propylene and a polymerizable unsaturated carboxylic acid such as (meth) acrylic acid and maleic acid, and the copolymer. At least one water-dispersible resin or a water-soluble resin selected from two types of resins obtained by adding a polymerizable unsaturated compound to the aqueous dispersion of No. 1 and emulsion-polymerizing and further intra-particle cross-linking can be preferably used.</p><p> The copolymer of the olefin and the polymerizable unsaturated carboxylic acid is a copolymer of one or more olefins and one or more polymerizable unsaturated carboxylic acids. In the copolymer, the monomer content of the unsaturated carboxylic acid is preferably in the range of 3 to 60% by weight, preferably 5 to 40% by weight. By neutralizing the acid group in this copolymer with a basic substance, it can be dispersed in water.</p><p> The polymerizable unsaturated compound in the crosslinked resin obtained by adding a polymerizable unsaturated compound to the aqueous dispersion of the copolymer, emulsion polymerization, and further cross-linking in the particles includes, for example, the water-dispersible or water-soluble. Examples thereof include the vinyl monomers listed in the description of the acrylic resin, and one type or two or more types can be appropriately selected and used.</p><p> The mixing ratio of the aqueous organic polymer compound (c) is 0.1 to 200 parts by weight, particularly 1 to 50 parts by weight, based on 100 parts by weight of the solid content of the titanium-containing aqueous liquid (a). , The obtained titanium oxide film is preferable from the viewpoints of gas barrier property, ultraviolet ray blocking property, fragrance retention property, process resistance and the like.</p><p> The coating agent for forming a titanium oxide film containing a titanium-containing aqueous liquid (a), an organic basic compound (b) and an aqueous organic polymer compound (c) stable at pH 10 or less is an aqueous coating agent having a pH of 2 to 10. Is preferable. When the pH is less than 2, the storage stability of the liquid tends to decrease, and when the pH exceeds 10, a precipitate is formed and the film-forming property tends to decrease.</p><p> The coating agent for forming a titanium oxide film used in the present invention may contain various additives, if necessary. Examples of the additive include commercially available titanium oxide sol, titanium oxide powder, pigment and the like. Examples of the pigment include mica, talc, silica, barium sulfate, clay and the like.</p><p> The thickness of the titanium oxide film layer (B) is usually preferably in the range of 0.001 to 10 μm, and particularly preferably in the range of 0.1 to 3 μm. If it is less than 0.001 μm, the gas barrier property and aroma retention property such as oxygen blocking property, carbon dioxide gas blocking property, and water vapor blocking property are lowered, and if it exceeds 10 μm, the titanium oxide film is easily cracked, so that the gas barrier property and the gas barrier property are reduced. Decreased fragrance retention.</p><p><u style="single">Preparation, layer composition and use of gas barrier film</u> In the gas barrier film of the present invention, for example, the surface of the plastic film layer (A) is coated with a coating agent for forming a titanium oxide film, and then heated at room temperature or at a temperature of 200 ° C. or lower, preferably 150 ° C. or lower. Then, it is dried to form a titanium oxide film layer (B). The titanium oxide film may be cured during this drying. If the heating temperature exceeds 200 ° C, the plastic film layer (A) may be deformed or deteriorated.</p><p> As a coating method for forming a titanium oxide, conventionally known means such as a coating method such as roller coating, immersion coating, spray coating and brush coating, and a printing method such as screen printing and letterpress printing can be used. ..</p><p> The coating agent for forming a titanium oxide film is applied and dried on one side or both sides of the plastic film layer (A), whereby the two-layer structure of the film layer (A) and the titanium oxide film layer (B) or titanium oxide is formed. A laminated film having a three-layer structure consisting of a film layer (B), the film layer (A), and a titanium oxide film layer (B) can be obtained. As described above, the thickness of each layer is usually in the range of about 5 to 100 μm for the film layer (A) and 0.001 to 10 μm for the titanium oxide film layer (B). The total thickness of the film is usually about 7 to 100 μm in both the two-layer laminated film and the three-layer laminated film.</p><p> In the above-mentioned two-layer laminated film and three-layer laminated film of the present invention, a hard coat layer, a scratch prevention layer, a heat seal layer, an adhesive layer and the like are always provided on one side or both sides of the laminated film, if necessary. By the method, it can be further laminated.</p><p> The gas barrier film of the present invention is suitably used for applications that require gas barrier properties such as oxygen blocking property, carbon dioxide gas blocking property, and water vapor blocking property, ultraviolet blocking property, fragrance retaining property, and transparency. Can be done.</p><p> Specifically, the film of the present invention can be used for containers, packaging and the like of various products in industrial fields such as foods, pharmaceuticals, medical treatments, electrical parts, agriculture and fisheries, fermentation and household products. In particular, the film of the present invention can be suitably used for containers, packaging, etc. of food and drink, and in this case, oxygen, fragrance, etc. dissolved in water, drink, food, etc. are transferred, oxygen, gas, etc. in the air are transferred. It can be effectively prevented from entering the container or packaging.</p>

<p> According to the present invention, by laminating a titanium oxide film layer on at least one surface of a plastic film, it is excellent in gas barrier properties such as oxygen blocking property, carbon dioxide gas blocking property, and water vapor blocking property, and also has ultraviolet blocking property and fragrance retention. A remarkable effect of providing a gas barrier film having excellent properties, transparency and the like can be obtained.</p><p> Further, at least one surface of the plastic film is oxidized by using a coating agent for forming a titanium oxide film containing a titanium-containing aqueous solution (a), an organic basic compound (b) and an aqueous organic polymer compound (c). When the titanium film layer is laminated, a remarkable effect of providing a gas barrier film having further improved workability and adhesion of the titanium oxide film can be obtained.</p><p> Further, according to the gas barrier film of the present invention, it is possible to obtain the effect that no special technique or equipment is required, the film can be manufactured only by a coating operation, and the manufacturing cost is low.</p>

<figref num="1">FIG. 1 is a drawing showing the X-ray diffraction result of the titanium oxide film forming coating agent (1) obtained in Production Example 1 described later.</figref>

Next, the present invention will be described in more detail with reference to Production Examples, Examples and Comparative Examples. However, the present invention is not limited to the following examples. The "parts" and "%" described in each example are based on weight.

<u style="single">Example of laminated film prepared using a coating agent which is a titanium-containing aqueous liquid (a1)</u> Manufacturing example 1 A mixture of 10 parts of tetra iso-propoxytitanium and 10 parts of iso-propanol was added dropwise to a mixture of 10 parts of 30% hydrogen peroxide solution and 100 parts of deionized water at 20 ° C. for 1 hour with stirring. Then, it was aged at 25 ° C. for 2 hours to obtain a titanium-containing aqueous solution which is a yellow transparent, slightly viscous, peroxotitanic acid aqueous solution having a solid content of 2%. This was used as a coating agent (1) for forming a titanium oxide film. The X-ray diffraction result of this coating agent (1) is shown in FIG. From FIG. 1, it can be seen that the titanium oxide in this coating agent is amorphous titanium oxide.

Manufacturing example 2 A titanium-containing aqueous solution having a solid content of 2% was obtained in the same manner as in Production Example 1 except that the same amount of tetra n-butoxytitanium was used instead of tetra iso-propoxytitanium in Production Example 1. This was used as a coating agent (2) for forming a titanium oxide film.

Manufacturing example 3 In Production Example 1, a titanium-containing aqueous solution having a solid content of 2% was obtained in the same manner as in Production Example 1 except that the same amount of tetraiso-propoxytitanium trimester was used instead of tetraiso-propoxytitanium. It was. This was used as a coating agent (3) for forming a titanium oxide film.

Manufacturing example 4 In Production Example 1, the solid content was 2% in the same manner as in Production Example 1, except that hydrogen peroxide solution was added dropwise at 50 ° C for 1 hour using a triple amount, and then aged at 60 ° C for 3 hours. A titanium-containing aqueous solution was obtained. This was used as a coating agent (4) for forming a titanium oxide film.

Manufacturing example 5 The titanium oxide coating agent (2) obtained in Production Example 2 was heat-treated at 95 ° C. for 6 hours to obtain a titanium-containing aqueous solution having a solid content of 2%, which is a white-yellow translucent titanium oxide dispersion. This was used as a coating agent (5) for forming a titanium oxide film.

Manufacturing example 6 10% aqueous ammonia was added dropwise to an aqueous solution of 5 cc of a 60% aqueous solution of titanium tetrachloride made up of 500 cc of distilled water to precipitate titanium hydroxide. After washing the precipitate with distilled water, 10 cc of a 30% hydrogen peroxide solution was added and stirred to obtain 70 cc of a titanium-containing aqueous liquid containing peroxotitanic acid and having a solid content of 2%, which is a yellow translucent viscous liquid. This was used as a coating agent (6) for forming a titanium oxide film.

Manufacturing example 7 A liquid in which titanium hydroxide was dispersed in water at 0.2 mol / l was prepared. This was used as a coating agent (7) for forming a titanium oxide film for comparison.

Examples 1 to 6 and Comparative Example 1 Coating agents (1) to (7) for forming a titanium oxide film are coated on one surface of a biaxially oriented polypropylene film having a film thickness of 20 μm, which has been subjected to corona discharge treatment, with a bar coater so that the dry film thickness is 0.3 μm. Then, it was dried at 120 ° C. for 5 minutes, and a titanium oxide film was laminated to obtain a laminated film. Examples 1 to 6 are when the coating agents (1) to (6) are used, and Comparative Example 1 is when the coating agents (7) are used.

Comparative Examples 2 and 3 Biaxially oriented polypropylene films or copolymerized polyethylene terephthalate films having a film thickness of 20 μm were designated as Comparative Examples 2 and 3, respectively.

For each of the films of Examples 1 to 6 and Comparative Examples 1 to 3, the coating film state, adhesiveness, pencil hardness and oxygen transmittance were tested by the following methods.

(1) Coating film condition: The presence or absence of coating film abnormalities such as smoothness, transparency, and cracks of the coating film was visually observed. Those without abnormalities were regarded as good.

(2) Adhesiveness: According to the grid tape method specified in JIS K5400 8.5.2 (1990), 100 squares of 1 mm x 1 mm were created, adhesive tape was adhered to the surface, and then peeled off. I checked the number of remaining squares.

(3) Pencil hardness: A pencil scratch test specified in JIS K5400 8.4.2 (1990) was conducted and evaluated based on the presence or absence of scratches.

(4) Oxygen permeability: Measured in water at 25 ° C using a Kaken-type film oxygen permeability meter (manufactured by Rika Seiki Kogyo Co., Ltd.). The unit is [cm³(STP) cm / cm² S cmHg].

Table 1 shows the film material and test results.

<tables num="1"><img file="JP4688401B2_D0001.tif" /></tables>

<u style="single">Example of laminated film prepared using a coating agent which is a titanium-containing aqueous liquid (a2)</u> Manufacturing example 8 A mixture of 10 parts of tetra iso-propoxytitanium and 10 parts of iso-propanol, 5 parts (solid content) of "TKS-201" (manufactured by Teika Co., Ltd., titanium oxide sol), 10 parts of 30% hydrogen peroxide solution and deionization. It was added dropwise to a mixture of 100 parts of water at 10 ° C. over 1 hour with stirring. Then, it was aged at 10 ° C. for 24 hours to obtain a titanium-containing aqueous solution which is a yellow transparent, slightly viscous, peroxotitanic acid aqueous solution having a solid content of 2%. This was used as a coating agent (8) for forming a titanium oxide film.

Manufacturing example 9 In Production Example 8, a titanium-containing aqueous solution having a solid content of 2% was obtained in the same manner as in Production Example 8 except that the same amount of tetra n-butoxytitanium was used instead of tetraiso-propoxytitanium. This was used as a coating agent (9) for forming a titanium oxide film.

Manufacturing example 10 In Production Example 8, a titanium-containing aqueous solution having a solid content of 2% was obtained in the same manner as in Production Example 8 except that the same amount of tetraiso-propoxytitanium trimester was used instead of tetraiso-propoxytitanium. .. This was used as a coating agent (10) for forming a titanium oxide film.

Production example 11 In Production Example 8, the solid content was 2% in the same manner as in Production Example 8, except that hydrogen peroxide solution was added dropwise at 10 ° C for 1 hour using a triple amount, and then aged at 10 ° C for 30 hours. A titanium-containing aqueous solution was obtained. This was used as a coating agent (11) for forming a titanium oxide film.

Examples 7-10 Coating agents (8) to (11) for forming a titanium oxide film are coated on one surface of a biaxially oriented polypropylene film having a film thickness of 20 μm, which has been subjected to corona discharge treatment, with a bar coater so that the dry film thickness is 0.3 μm. Then, the film was dried at 120 ° C. for 5 minutes, and a titanium oxide film was laminated to obtain a film of Examples 7 to 10.

For each of the films of Examples 7 to 10, the coating film state, adhesion, pencil hardness and oxygen permeability were tested by the above method.

Table 2 shows the film material and test results. For comparison, the results of Comparative Example 2 are also shown.

<tables num="2"><img file="JP4688401B2_D0002.tif" /></tables>

<u style="single">An example of a laminated film prepared by using a coating agent for forming a titanium oxide film containing a titanium-containing aqueous solution (a), an organic basic compound (b) and an aqueous organic polymer compound (c).</u> Manufacturing example 12 The titanium-containing aqueous solution obtained in Production Example 1 was heat-treated at 95 ° C. for 6 hours to obtain a titanium-containing aqueous solution having a solid content of 2%, which is a white-yellow translucent titanium oxide dispersion.

Production example 13 A mixture of 10 parts of tetra iso-propoxytitanium and 10 parts of iso-propanol, 5 parts (solid content) of "TKS-203" (manufactured by Teika Co., Ltd., titanium oxide sol), 10 parts of 30% hydrogen peroxide solution and deionization. It was added dropwise to a mixture of 100 parts of water at 10 ° C. over 1 hour with stirring. Then, it was aged at 10 ° C. for 24 hours to obtain a titanium-containing aqueous solution having a solid content of 2%, which is a yellow transparent, slightly viscous peroxotitanic acid aqueous solution.

Production example 14 In a reaction vessel, 1,200 parts of ethylene glycol monobutyl ether was placed, heated to 100 ° C and held, and then 400 parts of methacrylic acid, 500 parts of styrene, 100 parts of ethyl acrylate, and "Perbutyl O" (trade name, Japan). A mixture of 35 parts of a peroxide-based polymerization initiator manufactured by Yushi Co., Ltd. and 140 parts of ethylene glycol monobutyl ether was added dropwise over 3 hours. After completion of the dropping, the mixture was aged at 100 ° C. for 2 hours, and then 570 parts of n-butanol was added to obtain a carboxyl group-containing acrylic resin solution (AC-1) having a solid content of 36%. The number average molecular weight of the obtained resin was about 7,000, and the resin acid value was 260 mgKOH / g.

Next, 800 parts of "Araldide AER6129 resin" (trade name, manufactured by Asahi Kasei Epoxy Co., Ltd., epoxy resin having an epoxy equivalent of 2,600) and 129 parts of diethylene glycol monobutyl ether were added to another reactor, and the mixture was heated and stirred to uniformly dissolve the resin. did. To this solution, 556 parts of the above carboxyl group-containing acrylic resin solution (AC-1) was added, and the mixture was uniformly stirred and mixed. Then, 66 parts of dimethylethanolamine was added and kept at 90 ° C. for 1 hour, and then 2,450 parts of water was added dropwise over 1 hour with stirring to obtain a carboxyl group-containing acrylic-modified epoxy resin emulsion having a solid content of 25%. Obtained.

Production example 15 "Epicoat 1009 resin" (trade name, manufactured by Shell Chemical Co., Ltd., epoxy resin with a molecular weight of 3,750) 1,880 g (0.5 mol) and methyl in a reactor equipped with a stirrer, a reflux condenser, a thermometer, and a liquid dropping device. After adding 1,000 g of a mixed solvent of isobutyl ketone / xylene = 1/1 (weight ratio), the mixture was heated and stirred to uniformly dissolve it. Then, the mixture was cooled to 70 ° C., and 70 g of di (n-propanol) amine separated by a liquid dropping device was added dropwise over 30 minutes. During this time, the reaction temperature was maintained at 70 ° C. After completion of the dropping, the mixture was held at 120 ° C. for 2 hours to complete the reaction, thereby obtaining an amine-modified epoxy resin having a solid content of 66%. 25 parts of 88% formic acid was mixed with 1,000 g of the obtained resin, water was added, and the mixture was sufficiently stirred to obtain an amine-modified epoxy resin emulsion having a solid content of 30%.

Manufacturing example 16 For 50 parts of "Hopezol A-5100X" (trade name, manufactured by Kyowa Hakko Kogyo Co., Ltd., acrylic-modified polyester resin solution with 60% solid content), "My Coat 106" (trade name, manufactured by Mitsui Cytec Co., Ltd.) , 4 parts of benzoguanamine resin with 77% solid content) and 6 parts of "NACURE 5225" (manufactured by King Industries, Ltd., trade name, amine-neutralized solution of dodecylbenzenesulfonic acid, dodecylbenzenesulfonic acid content is 25%) The mixture was mixed, water was added, and the mixture was sufficiently stirred to obtain an acrylic-modified polyester / melamine curable resin solution having a solid content of 30%.

Production example 17 As the water-based urethane resin, "ADEKA BONTITER HUX-401" (trade name, manufactured by Asahi Denka Co., Ltd., water-based urethane resin dispersion having a solid content of 37%) was used.

Production example 18 ~ 26 According to the composition ratios shown in Table 3 below, an organic basic compound is placed in a titanium-containing aqueous solution and stirred, and then an aqueous organic polymer compound is added and stirred. (12) to (20) were prepared. The coating agents (12) to (19) are for examples, and the coating agents (20) are for comparison.

Table 3 shows the composition ratio of each coating agent.

<tables num="3"><img file="JP4688401B2_D0003.tif" /></tables>

Examples 11-18 and Comparative Example 4 Coating agents (12) to (19) for forming a titanium oxide film are coated on one surface of a biaxially oriented polypropylene film having a film thickness of 20 μm, which has been subjected to corona discharge treatment, with a bar coater so that the dry film thickness is 0.3 μm. Then, the film was dried at 120 ° C. for 5 minutes, and a titanium oxide film was laminated to obtain a film of Examples 11 to 18. Further, using the titanium oxide film forming coating agent (20), the film of Comparative Example 4 was obtained in the same manner.

Each film was tested for coating film condition, adhesion, pencil hardness and oxygen permeability by the above method. In addition, the stability of the coating liquid and the oxygen permeability after rubbing were tested by the following method.

(5) Coating stability: The stability of the coating was evaluated based on the presence or absence of abnormalities such as separation and gelation after storing the coating at 40 ° C for 1 month. The case where there was no abnormality was regarded as good.

(6) Oxygen permeability after rubbing: A load of 500 g is applied to a 5 cm wide film, and a 10 mmφ stainless steel tube is wound and unwound 10 times each so that the coated surface of the coating agent is on the inside. After repeating, the oxygen permeability of the film was measured by the above method.

The test results are shown in Table 4.

<tables num="4"><img file="JP4688401B2_D0004.tif" /></tables>