Laminate, recycled material using said laminate, method for manufacturing recycled substrate using said laminate, and method for manufacturing recycled plastic pellets using said recycled substrate

Abstract

The present invention solves this problem by providing a laminate having at least a first substrate film, a gas barrier coating layer (A), an ink layer (B), and a second substrate film, wherein the ink layer (B) contains a polyurethane resin, and the amine value of the non-volatile components of the polyurethane resin is 0.1 mgKOH / g to 10 mgKOH / g. The present invention also provides a recycled material using the laminate, a method for producing a recycled substrate, and a method for producing recycled plastic pellets, in which the recycled substrate obtained by the method for producing a recycled substrate is molded in a molding machine.

Description

[Technical Field]

[0001] The present invention relates to a laminate, a recycled material using the laminate, a method for producing a recycled substrate using the laminate, and a method for producing recycled plastic pellets using the recycled substrate. [Background technology]

[0002] In recent years, there has been a demand for mono-material packaging materials to facilitate recycling, and among these, the use of olefin-based films as mono-materials is highly feasible and is being actively considered. However, compared to polyethylene terephthalate (PET) and nylon, olefin-based films have significantly inferior barrier properties, which is a major obstacle to the use of mono-materials. To improve the barrier properties of packaging materials, studies are being conducted on the application of inorganic vapor deposition layers to olefin-based substrates, but this leads to increased manufacturing costs and poses a barrier to widespread use. Therefore, methods are being investigated that use barrier coating agents to impart barrier properties greater than those of PET film or nylon film.

[0003] On the other hand, gravure inks and flexographic inks are widely used to impart aesthetic appeal and functionality to printed materials. In the case of laminate films using a barrier coating agent, the structure is typically film / barrier coating layer / ink layer / film, or film / ink layer / barrier coating layer / film. Such laminate films are often processed using adhesive lamination, as well as extrusion lamination, in which molten resin is extruded without the use of adhesive. However, depending on the combination of the barrier coating layer and ink, unless one of the structures (e.g., film / barrier coating layer / ink layer / film) is used, the laminate strength (dry lamination strength or extrusion lamination strength) may be poor, which may impose manufacturing limitations.

[0004] In addition, to improve the properties of printed matter, a curing agent is added to the liquid ink composition, but the addition of a curing agent can increase the viscosity of inks with poor two-component stability, which can lead to poor printability.

[0005] Furthermore, current recycling methods pose the problem that the printed layer printed on the plastic substrate does not come off during the recycling process and becomes mixed into the plastic, causing a deterioration in color and physical properties, thereby reducing the value of the recycled plastic.

[0006] Furthermore, given the industry trends described above, laminate films that use barrier coating agents have issues such as reduced ink adhesion and reduced laminate strength, and there is a demand for laminate films that solve these issues. For example, Patent Document 1 discloses a coating agent containing a resin (A) and an aqueous solvent (B), wherein the resin (A) contains a vinyl alcohol polymer (A1) and a polyalkyleneimine (A2). However, the patent document does not disclose the adhesion between the ink and the coating agent or the lamination strength. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] International Publication No. 2022 / 124171 Summary of the Invention [Problem to be solved by the invention]

[0008] The problem to be solved by the present invention is to provide a laminate that uses a liquid ink resin composition that is excellent in both adhesion and two-component stability, has excellent gas barrier properties and (extrusion) lamination strength, and has no restrictions on the order in which the ink layer and barrier coat layer are laminated.The present invention also provides a recycled material using the laminate, a method for producing a recycled substrate using the laminate, and a method for producing recycled plastic pellets using the recycled substrate. [Means for solving the problem]

[0009] As a result of extensive research into solving the above problems, the inventors have completed the present invention by providing a laminate having at least a first base film, a gas barrier coating layer (A), an ink layer (B), and a second base film, wherein the ink layer (B) contains a polyurethane resin, and the amine value of the non-volatile components of the polyurethane resin is 0.1 mgKOH / g to 10 mgKOH / g.

[0010] That is, the present invention includes the following aspects. [1] A laminate comprising at least a first base film, a gas barrier coating layer (A), an ink layer (B), and a second base film, wherein the ink layer (B) contains a polyurethane resin, and the amine value of the non-volatile components of the polyurethane resin is 0.1 mgKOH / g to 10 mgKOH / g. [2] The laminate according to [1], wherein the gas barrier coat layer (A) is a dried coating film of a barrier coating agent (SB) containing a polyester polyol obtained by polycondensation of an acid component containing an ortho- or meta-oriented aromatic polycarboxylic acid with a polyhydric alcohol, and an isocyanate compound (SB-B). [3] The laminate according to [1], wherein the gas barrier coat layer (A) is a dried coating film of a barrier coating agent (WB) containing a vinyl alcohol polymer having a degree of saponification of 90% or more and an aqueous solvent (WB-B). [4] The laminate according to [3], wherein the barrier coating agent (WB) further contains a polyalkyleneimine. [5] The laminate according to [1], wherein the ink layer (B) further contains one or more resins selected from the group consisting of cellulose-based resins, vinyl chloride-vinyl acetate resins, polyester resins, acrylic resins, polyamide resins, rosin-modified maleic acid resins, polyvinyl butyral resins, ketone aldehyde resins, and chlorinated polyolefin resins. [6] The laminate according to [1], wherein the chlorine content in the resin component contained in the ink layer (B) is 5% by mass or less. [7] The laminate according to [1], wherein the first base film, the gas barrier coating layer (A), the ink layer (B), and the second base film are laminated in this order, or the first base film, the ink layer (B), the gas barrier coating layer (A), and the second base film are laminated in this order. [8] The laminate according to [1], wherein the second base film includes a melt-extruded resin layer. [9] The laminate according to [8], which has an anchor coat layer between the ink layer (B) and the second base film, or between the gas barrier coat layer (A) and the second base film, and the anchor coat layer is made of one or more resins selected from the group consisting of polyethyleneimine-based resins, polybutadiene-based resins, and polyisocyanate-based resins.

[10] The laminate according to [1], wherein the first base film and the second base film are both made of a polyolefin resin.

[11] The laminate according to [1], which has a removable primer layer either between the first base film and the ink layer (B) or between the ink layer (B) and the second base film.

[12] The laminate according to

[11] , wherein the removable primer layer is soluble in an alkaline solution.

[13] A recycled material using the laminate described in

[11] .

[14] A method for producing a recycled substrate, comprising treating the laminate according to

[11] with an alkaline solution to dissolve the detachable primer layer, thereby removing the ink layer from the laminate.

[15] A method for producing recycled plastic pellets, which comprises molding the recycled substrate obtained by the method for producing recycled substrates according to

[14] using a molding machine. [Effects of the Invention]

[0011] The present invention can provide a laminate that uses a liquid ink resin composition that is excellent in both adhesion and two-component stability, has excellent gas barrier properties and (extrusion) lamination strength, and has no restrictions on the order in which the barrier coat layer and the ink layer are laminated.The present invention also can provide a recycled material using the laminate, a method for producing a recycled substrate using the laminate, and a method for producing recycled plastic pellets using the recycled substrate. DETAILED DESCRIPTION OF THE INVENTION

[0012] The following describes in detail an embodiment of the present invention (hereinafter referred to as "the present embodiment"); however, the present invention is not limited to the following description and can be implemented in various modifications within the scope of its gist.

[0013] [Definition] Before proceeding to a detailed description of the present invention, the definitions of the terms used in this specification will be explained. In this specification, "for laminate films" means that the ink is used in a laminate type structure in which a coating film (various layers or films) is further formed on the ink layer. In this specification, the term "liquid ink composition" refers to a liquid printing ink, such as gravure ink or flexographic ink, that is applied to a printing method using a printing plate, and is preferably gravure ink or flexographic ink. In addition, all "ink" used in the following description refers to "printing ink." In this specification, all "parts" refer to "parts by mass," "total amount of ink" refers to the total amount of ink including all volatile components such as solvents, and "(ink or resin) non-volatile components (total amount)" refers to the total amount of only non-volatile components, excluding volatile components.

[0014] The laminate of the present invention has at least a first base film, a gas barrier coating layer (A), an ink layer (B), and a second base film.

[0015] [Gas barrier coating layer (A)] In the present invention, the gas barrier coating layer (A) is obtained by applying and drying a barrier coating agent. The barrier coating agent may be a solvent-based barrier coating agent (SB) or a water-based barrier coating agent (WB).

[0016] <Solvent-based barrier coating agent (SB)> The solvent-based barrier coating agent preferably contains a polyester polyol (SB-A) and an isocyanate compound (SB-B). Generally, polyol compounds and isocyanate compounds are highly reactive with each other, so coating agents made from these compounds are typically used as a "two-component curing agent," in which the polyester polyol (SB-A) and the isocyanate compound (SB-B) are mixed immediately before coating. This solvent-based barrier coating agent is also typically used as a two-component curing coating agent. The term "two-component" refers to a polyol composition containing the polyester polyol (SB-A) as the primary component, and an isocyanate composition containing the isocyanate compound (SB-B) as the primary component.

[0017] (Polyester polyol (SB-A)) The polyester polyol (SB-A) is more preferably a polyester polyol obtained by polycondensation of an acid component containing an ortho-oriented aromatic polycarboxylic acid or a meta-oriented polycarboxylic acid with a polyol component, and even more preferably a polyester polyol obtained by polycondensation of an acid component containing an ortho-oriented aromatic polycarboxylic acid with a polyhydric alcohol.

[0018] (Acid component: ortho-oriented aromatic polycarboxylic acid or meta-oriented polycarboxylic acid) Examples of ortho-oriented aromatic polycarboxylic acids include orthophthalic acid or its anhydride, naphthalene 2,3-dicarboxylic acid or its anhydride, naphthalene 1,2-dicarboxylic acid or its anhydride, anthraquinone 2,3-dicarboxylic acid or its anhydride, and 2,3-anthracene carboxylic acid or its anhydride. These compounds may have a substituent on any carbon atom of the aromatic ring. Examples of the substituent include a chloro group, a bromo group, a methyl group, an ethyl group, an i-propyl group, a hydroxyl group, a methoxy group, an ethoxy group, a phenoxy group, a methylthio group, a phenylthio group, a cyano group, a nitro group, an amino group, a phthalimide group, a carboxyl group, a carbamoyl group, an N-ethylcarbamoyl group, a phenyl group, or a naphthyl group.

[0019] Examples of meta-oriented polycarboxylic acids include isophthalic acid and 1,3-naphthalenedicarboxylic acid. These compounds may have a substituent on any carbon atom of the aromatic ring. Examples of the substituent include a chloro group, a bromo group, a methyl group, an ethyl group, an i-propyl group, a hydroxyl group, a methoxy group, an ethoxy group, a phenoxy group, a methylthio group, a phenylthio group, a cyano group, a nitro group, an amino group, a phthalimide group, a carboxyl group, a carbamoyl group, an N-ethylcarbamoyl group, a phenyl group, and a naphthyl group.

[0020] (Acid component and other polycarboxylic acids) The acid component used in the synthesis of polyester polyol (SB-A) may contain a polycarboxylic acid other than the ortho-oriented aromatic polycarboxylic acid or meta-oriented polycarboxylic acid. Examples of such a polycarboxylic acid include aliphatic polycarboxylic acids such as succinic acid, adipic acid, azelaic acid, sebacic acid, and dodecanedicarboxylic acid; unsaturated bond-containing polycarboxylic acids such as maleic anhydride, maleic acid, and fumaric acid; alicyclic polycarboxylic acids such as 1,3-cyclopentanedicarboxylic acid and 1,4-cyclohexanedicarboxylic acid; terephthalic acid, pyromellitic acid, trimellitic acid, 1,4-naphthalenedicarboxylic acid, 1,5-anthracenedicarboxylic acid, 2,5-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, naphthalic acid, and 1,4-anthracenedicarboxylic acid. Examples of aromatic polycarboxylic acids include helical dicarboxylic acids, 2,6-anthracene dicarboxylic acid, 2,7-anthracene dicarboxylic acid, 1,8-anthracene dicarboxylic acid, 9,10-anthracene dicarboxylic acid, biphenyl dicarboxylic acid, 1,2-bis(phenoxy)ethane-p,p'-dicarboxylic acid, and the anhydrides or ester-forming derivatives of these dicarboxylic acids, p-hydroxybenzoic acid, p-(2-hydroxyethoxy)benzoic acid, and the ester-forming derivatives of these dihydroxycarboxylic acids, and the like, and one or more of these can be used in combination. Among these, succinic acid, 1,3-cyclopentane dicarboxylic acid, and the anhydrides thereof are preferred.

[0021] When the acid component contains a polycarboxylic acid other than an ortho-oriented aromatic polycarboxylic acid or a meta-oriented polycarboxylic acid, the proportion of the ortho-oriented aromatic polycarboxylic acid or the meta-oriented polycarboxylic acid in the total amount of the acid component is preferably 40 to 100 mass%.

[0022] (Polyol component) The polyol component used in the synthesis of polyester polyol (SB-A) is preferably a polyhydric alcohol, and preferably contains a dihydric alcohol such as ethylene glycol, propylene glycol, butylene glycol, neopentyl glycol, or cyclohexanedimethanol, or a trihydric alcohol such as glycerol, trimethylolethane, or trimethylolpropane. Among these, it is more preferable to contain ethylene glycol or glycerol. It is particularly preferable to contain glycerol. The polyol component preferably contains 10 to 100% by mass of glycerol.

[0023] The polyol component may be used in combination with polyhydric alcohols other than those mentioned above. Examples of the polyol component include aliphatic diols such as 1,5-pentanediol, 3-methyl-1,5-pentanediol, 1,6-hexanediol, methylpentanediol, dimethylbutanediol, butylethylpropanediol, diethylene glycol, triethylene glycol, tetraethylene glycol, dipropylene glycol, and tripropylene glycol; trihydric or higher polyhydric alcohols such as glycerin, trimethylolpropane, trimethylolethane, tris(2-hydroxyethyl)isocyanurate, 1,2,4-butanetriol, pentaerythritol, and dipentaerythritol; hydroquinone, resorcinol, catechol, naphthalenediol, biphenol, bisphenol A, bisphenol F, and tetramethylbiphenol; ethylene oxide-extended products of these; and aromatic polyhydric phenols such as hydrogenated alicyclic phenols.

[0024] (Polyester polyol (SB-A)) When the polyester polyol (SB-A) has three or more hydroxyl groups, some of the hydroxyl groups may be modified with acid groups. Such a polyester polyol is hereinafter also referred to as polyester polyol (SB-A'). The polyester polyol (SB-A') is obtained by reacting a polyester polyol with a polycarboxylic acid or its acid anhydride. The proportion of hydroxyl groups modified with the polycarboxylic acid is preferably 1 / 3 or less of the hydroxyl groups in the polyester polyol (SB-A). Examples of polycarboxylic acids used for modification include, but are not limited to, succinic anhydride, maleic acid, fumaric acid, 1,2-cyclohexanedicarboxylic anhydride, 4-cyclohexene-1,2-dicarboxylic anhydride, 5-norbornene-2,3-dicarboxylic anhydride, phthalic anhydride, 2,3-naphthalenedicarboxylic anhydride, trimellitic anhydride, oleic acid, and sorbic acid.

[0025] The hydroxyl value of the polyester polyol (SB-A) is preferably 20 mg KOH / g or more and 250 mg KOH / g or less. If the hydroxyl value is 20 mg KOH / g or more, the molecular weight is optimal and the viscosity of the polyol composition is suitable, and for example, when used as a coating agent, there is no need to increase the coating temperature. Furthermore, if the hydroxyl value is 250 mg KOH / g or less, the crosslink density of the cured coating film is suitable and sufficient adhesive strength is obtained.

[0026] When the polyester polyol (SB-A) has acid groups, the acid value is preferably 200 mg KOH / g or less. If the acid value is 200 mg KOH / g or less, the reaction between the polyol and the polyisocyanate does not proceed too quickly, resulting in good coating suitability. The lower limit of the acid value is not particularly limited, but an example is 20 mg KOH / g or more. If the acid value is 20 mg KOH / g or more, good gas barrier properties and initial cohesion can be obtained due to intermolecular interactions. The hydroxyl value of the polyester polyol (SB-A) can be measured using the hydroxyl value measurement method specified in JIS-K0070, and the acid value can be measured using the acid value measurement method specified in JIS-K0070.

[0027] The number average molecular weight of the polyester polyol (SB-A) is particularly preferably 300 to 5000, since a crosslinking density sufficient to achieve an excellent balance between adhesiveness and gas barrier properties can be obtained. The number average molecular weight is more preferably 350 to 3000. The number average molecular weight is calculated from the obtained hydroxyl value and the designed number of functional hydroxyl groups.

[0028] The glass transition temperature of the polyester polyol (SB-A) is preferably −30° C. or higher and 80° C. or lower, more preferably 0° C. or higher and 60° C. or lower, and even more preferably 25° C. or higher and 60° C. or lower, in order to achieve a balance between adhesion to the substrate and gas barrier properties.

[0029] The polyester polyol (SB-A) may be a polyester polyurethane polyol having a number average molecular weight of 1,000 to 15,000 obtained by urethane elongation through a reaction with a diisocyanate compound. The urethane-elongated polyester polyol contains components with molecular weights above a certain level and urethane bonds, and therefore has excellent gas barrier properties and initial cohesion.

[0030] The polyester polyol (SB-A) may be used alone or in combination of two or more polyol types.

[0031] (Isocyanate Compound (SB-B)) The isocyanate compound (SB-B) can be a conventionally known compound without any particular limitation, and examples thereof include adducts obtained by reacting tetramethylene diisocyanate, hexamethylene diisocyanate, toluene diisocyanate, diphenylmethane diisocyanate, hydrogenated diphenylmethane diisocyanate, xylylene diisocyanate, hydrogenated xylylene diisocyanate, isophorone diisocyanate, or trimers of these isocyanate compounds, and an excess amount of these isocyanate compounds with low-molecular-weight active hydrogen compounds such as ethylene glycol, propylene glycol, meta-xylylene alcohol, 1,3-bishydroxyethylbenzene, 1,4-bishydroxyethylbenzene, trimethylolpropane, glycerol, pentaerythritol, erythritol, sorbitol, ethylenediamine, monoethanolamine, diethanolamine, triethanolamine, and meta-xylylenediamine, and alkylene oxide adducts thereof, various polyester resins, polyether polyols, and high-molecular-weight active hydrogen compounds such as polyamides. Polyester polyisocyanates obtained by reacting a polyester polyol with a diisocyanate compound in an isocyanate excess ratio relative to hydroxyl groups may also be used. These may be used alone or in combination of two or more.

[0032] In addition, a blocked isocyanate may be used as the isocyanate compound (SB-B). Examples of isocyanate blocking agents include phenols such as phenol, thiophenol, methylthiophenol, ethylthiophenol, cresol, xylenol, resorcinol, nitrophenol, and chlorophenol; oximes thereof such as acetoxime, methyl ethyl ketoxime, and cyclohexanone oxime; alcohols such as methanol, ethanol, propanol, and butanol; halogen-substituted alcohols such as ethylene chlorohydrin and 1,3-dichloro-2-propanol; tertiary alcohols such as t-butanol and t-pentanol; and lactams such as ε-caprolactam, δ-valerolactam, γ-butyrolactam, and β-propylolactam. Other examples include aromatic amines, imides, active methylene compounds such as acetylacetone, acetoacetic ester, and ethyl malonate, mercaptans, imines, ureas, diaryl compounds, and sodium bisulfite. The blocked isocyanate can be obtained by subjecting the above-mentioned isocyanate compound and an isocyanate blocking agent to an addition reaction using a known, conventional method.

[0033] The isocyanate compound (SB-B) preferably has an aromatic ring or an aliphatic ring, which is expected to improve the gas barrier properties and blocking resistance of the coating film. Among the isocyanate compounds, examples of the isocyanate compound having an aromatic ring or an aliphatic ring include toluene diisocyanate, diphenylmethane diisocyanate, hydrogenated diphenylmethane diisocyanate, xylylene diisocyanate, hydrogenated xylylene diisocyanate, isophorone diisocyanate, or trimers of these isocyanate compounds, and adducts obtained by reacting an excess amount of these isocyanate compounds with low-molecular-weight active hydrogen compounds such as ethylene glycol, propylene glycol, meta-xylylene alcohol, 1,3-bishydroxyethylbenzene, 1,4-bishydroxyethylbenzene, trimethylolpropane, glycerol, pentaerythritol, erythritol, sorbitol, ethylenediamine, monoethanolamine, diethanolamine, triethanolamine, and meta-xylylenediamine, and alkylene oxide adducts thereof, various polyester resins, polyether polyols, and polymeric active hydrogen compounds such as polyamides.

[0034] The isocyanate compound (SB-B) may be used alone or in combination of two or more types of isocyanate compounds.

[0035] When a polyester polyol having residual carboxylic acid groups, such as polyester polyol (SB-A'), is used as the polyester polyol (SB-A), an epoxy compound may be used in combination with the isocyanate compound (SB-B). Examples of the epoxy compound include diglycidyl ether of bisphenol A and its oligomer, diglycidyl ether of hydrogenated bisphenol A and its oligomer, orthophthalic acid diglycidyl ester, isophthalic acid diglycidyl ester, terephthalic acid diglycidyl ester, p-oxybenzoic acid diglycidyl ester, tetrahydrophthalic acid diglycidyl ester, hexahydrophthalic acid diglycidyl ester, succinic acid diglycidyl ester, adipic acid diglycidyl ester, sebacic acid diglycidyl ester, ethylene glycol diglycidyl ether, and propylene glycol diglycidyl. ether, 1,4-butanediol diglycidyl ether, 1,6-hexanediol diglycidyl ether, polyalkylene glycol diglycidyl ethers, trimellitic acid triglycidyl ester, triglycidyl isocyanurate, 1,4-diglycidyloxybenzene, diglycidyl propylene urea, glycerol triglycidyl ether, trimethylolethane triglycidyl ether, trimethylolpropane triglycidyl ether, pentaerythritol tetraglycidyl ether, triglycidyl ethers of glycerol alkylene oxide adducts, and the like.

[0036] When an epoxy compound is used, a commonly known epoxy curing accelerator may be added as needed to accelerate curing, provided that the object of the present invention is not impaired.

[0037] In the present invention, the barrier coat layer (A) is preferably a dried coating film of a barrier coating agent (SB) containing a polyester polyol obtained by polycondensation of an acid component containing an ortho- or meta-oriented aromatic polycarboxylic acid with a polyhydric alcohol, and an isocyanate compound (SB-B).

[0038] (Other ingredients) (Plate-shaped inorganic compound (SB-E)) The solvent-based barrier coating agent (SB) may contain a plate-like inorganic compound (SB-E), which has the effect of improving the winding suitability after coating by reducing adhesion and improving gas barrier properties.

[0039] When a plate-like inorganic compound (SB-E) is used in combination, its plate-like shape improves barrier properties. While the interlayer charge of the plate-like inorganic compound (SB-E) does not directly affect barrier properties significantly, its dispersibility in the solvent-based barrier coating agent (SB) is significantly inferior for ionic inorganic compounds or inorganic compounds that swell in water. Increasing the amount added can cause the solvent-based barrier coating agent (SB) to thicken or become thixotropic, making coatability an issue. In contrast, when uncharged (nonionic) or non-water-swelling compounds are used, increasing the amount added can prevent thickening or thixotropy, ensuring coatability. Examples of the plate-like inorganic compound (SB-E) include hydrous silicates (phyllosilicate minerals, etc.), kaolin, kaolinite-serpentine group clay minerals (halloysite, kaolinite, endelite, dickite, nacrite, etc., antigorite, chrysotile, etc.), pyrophyllite-talc group (pyrophyllite, talc, kerolite, etc.), smectite group clay minerals (montmorillonite, beidellite, nontronite, saponite, hectorite, sauconite, stevensite, etc.), vermiculite group clay minerals (vermiculite, etc.), mica or mica group clay minerals (muscovite, phlogopite, etc. mica, margarite, tetrasilylic mica, taeniolite, etc.), chlorite group (cookkeite, sudoite, clinochlore, chamosite, nimite, etc.), hydrotalcite, plate-like barium sulfate, boehmite, aluminum polyphosphate, etc. These minerals may be natural clay minerals or synthetic clay minerals. The plate-like inorganic compounds (SB-E) may be used alone or in combination of two or more. There are no particular restrictions on the aspect ratio, content in the coating agent, particle size, and particle size distribution of these plate-like inorganic compounds (SB-E), as long as they can provide barrier improvement and blocking resistance.

[0040] The amount of the plate-like inorganic compound (SB-E) is preferably 5% by mass or more and 80% by mass or less of the non-volatile components of the solvent-based barrier coating agent (SB). Within this range, improvements in the adhesion of the coating agent to the substrate, the coating appearance, and the gas barrier properties of the coating film are expected. A blending amount of 10% to 60% is more preferable, and a blending amount of 20% to 50% is most preferable.

[0041] The plate-like inorganic compound (SB-E) can be dispersed in the solvent-based barrier coating agent (SB) using known dispersion methods. Examples include ultrasonic homogenizers, high-pressure homogenizers, paint conditioners, ball mills, roll mills, sand mills, sand grinders, Dyno Mills, Dispermats, Nano Mills, SC Mills, and Nanomizers. Even more preferred are devices capable of generating high shear forces, such as Henschel mixers, pressure kneaders, Banbury mixers, planetary mixers, two-roll mills, and three-roll mills. One of these devices may be used alone, or two or more types of devices may be used in combination.

[0042] The solvent-based barrier coating agent (SB) may contain a compound having an active hydrogen group. In this case, it is preferable to use a compound (SB-C) having an active hydrogen group with a molecular weight of 100 to 250 or a solubility parameter of 29.5 or less. When the compound (SB-C) is contained, the active hydrogen group forms a hydrogen bond network with the urethane bonds in the coating film, which is thought to control molecular motion and improve gas barrier properties.

[0043] Examples of the compound (SB-C) having a hydroxyl group as the active hydrogen group include alkanols such as octanol and decanol, aliphatic diols such as 1,5-pentanediol, 1,6-hexanediol, neopentyl glycol, 3-methyl-1,5-pentanediol, 2,2,2-trimethylpentanediol, 3,3-dimethylolheptane, octanediol, and decanediol, alicyclic alcohols such as 1,3- or 1,4-cyclohexanedimethanol and 1,3- or 1,4-cyclohexanediol, aromatic alcohols such as salicylic alcohol and vanillyl alcohol, hydrogenated bisphenol A, and 1,4-dihydroxy-2-butene. dihydric alcohols such as 2,6-dimethyl-1-octene-3,8-diol, bisphenol A, diethylene glycol, triethylene glycol, and dipropylene glycol; trihydric alcohols such as glycerin, trimethylolpropane, and triisopropanolamine; tetrahydric alcohols such as tetramethylolmethane (pentaerythritol) and diglycerin; pentahydric alcohols such as xylitol; hexahydric alcohols such as sorbitol, mannitol, allitol, iditol, dulcitol, altritol, inositol, and dipentaerythritol; and heptahydric alcohols such as perseitol.

[0044] Examples of the compound (SB-C) having an amino group as the active hydrogen group include aliphatic amines such as octylamine, decaneamine, 1,8-diaminooctane, and 1,10-diaminodecane; alicyclic amines such as isophoronediamine, norbornenediamine, bis(aminomethyl)cyclohexane, cyclohexanediamine, diaminodicyclohexylmethane, and methylenebis(methylcyclohexaneamine); and aromatic amines such as 1-xylylenediamine, N-benzylethylenediamine, phenylenediamine, diaminodiphenylmethane, diaminodiphenyl ether, 1,3-bis(3-aminophenoxy)benzene, toluenediamine, and diethyltoluenediamine.

[0045] Examples of the compound (SB-C) having an SH group as the active hydrogen group include hexyl mercaptan, heptyl mercaptan, octyl mercaptan, nonyl mercaptan, decyl mercaptan, undecyl mercaptan, dodecyl mercaptan, tridecyl mercaptan, tetradecyl mercaptan, pentadecyl mercaptan, mercaptophenol, mercaptopropionic acid, mercaptobutyric acid, 1,4-butanedithiol, and 2-mercaptobenzothiazole. , 3-mercapto-1,2-propanediol, mercaptomethylbutanol, 3-mercapto-2-methylpentanol, 3-mercapto-3-methylbutanol, 4-ethoxy-2-methyl-2-butanethiol, hexanethiol, dimethylthiophenol, 1,4-bis(3-mercaptobutyryloxy)butane, trimethylolpropane tris(3-mercaptobutyrate), pentaerythritol tetrakis(3-mercaptobutyrate), etc.

[0046] The compound (SB-C) may be used alone or in combination of two or more kinds. Among them, the compound (SB-C) having a hydroxyl group as the active hydrogen group is preferred, and isosorbide, tris(2-hydroxyethyl) isocyanurate, trimethylolpropane, dipentaerythritol, and 1,4-cyclohexanedimethanol are preferred.

[0047] The blending amount of the compound (SB-C) is preferably 0.5% by mass or more and 20% by mass or less of the non-volatile components of the solvent-based barrier coating agent. Within this range, winding blocking during coating is prevented, and good substrate adhesion and improved gas barrier properties of the coating film are expected. A blending amount of 1% by mass or more and 15% by mass or less is more preferred, and 2% by mass or more and 8% by mass or less is most preferred.

[0048] (acid anhydride) Known acid anhydrides can also be used as additives in solvent-based barrier coatings (SB) to improve the acid resistance of the coating layer. Examples of acid anhydrides include phthalic anhydride, succinic anhydride, HET anhydride, HIMIC anhydride, maleic anhydride, tetrahydrophthalic anhydride, hexahydraphthalic anhydride, tetrabromophthalic anhydride, tetrachlorophthalic anhydride, trimellitic anhydride, pyromellitic anhydride, benzophenotetracarboxylic anhydride, 2,3,6,7-naphthalenetetracarboxylic dianhydride, 5-(2,5-oxotetrahydrofuryl)-3-methyl-3-cyclohexene-1,2-dicarboxylic anhydride, and styrene-maleic anhydride copolymer. It is preferable to use non-petroleum-derived components as raw materials for these acid anhydrides, as this increases the proportion of non-petroleum-derived components. An example of such a compound is succinic anhydride.

[0049] (gas trapping component) Furthermore, if necessary, a material having a gas trapping function may be added. Examples of materials having an oxygen trapping function include low-molecular-weight organic compounds that react with oxygen, such as hindered phenols, vitamin C, vitamin E, organic phosphorus compounds, gallic acid, and pyrogallol, and transition metal compounds such as cobalt, manganese, nickel, iron, and copper. Examples of materials having a water vapor trapping function include silica gel, zeolite, activated carbon, and calcium carbonate. In addition to these, a trapping component for the target gas to be blocked can also be added.

[0050] (Other ingredients) The solvent-based barrier coating agent (SB) may also contain various additives within the range that does not impair the gas barrier auxiliary function. Examples of additives include inorganic fillers such as silica, alumina, aluminum flakes, and glass flakes, and when inorganic materials are used, dispersants, stabilizers (antioxidants, heat stabilizers, ultraviolet absorbers, etc.), plasticizers, antistatic agents, lubricants, antiblocking agents, colorants, leveling agents, and slip improvers.

[0051] Since the compound (SB-C) has an active hydrogen group, it is usually preferable to use it by blending it with the polyester polyol (SB-A).The plate-like inorganic compound (SB-E) does not particularly contribute to reactivity, so it may be blended with either the polyester polyol (SB-A) or the isocyanate compound (SB-B).

[0052] In the solvent-based barrier coating agent (SB), the reactive component of the isocyanate compound contained in the isocyanate compound (SB-B) and the hydroxyl group of the polyol contained in the polyester polyol (SB-A) are preferably blended in an equivalent ratio of 0.5 / 1 to 5 / 1, and from the viewpoint of barrier function and blocking resistance, a ratio of 0.8 / 1 to 2.5 / 1 is more preferable. Within this range, blocking resistance and adhesive strength are improved.

[0053] (Solvent used in solvent-based barrier coatings (SB)) The solvent-based barrier coating agent (SB) may contain a solvent as appropriate. From the viewpoint of quick-drying properties and water vapor barrier function, the solvent used is preferably non-aqueous, and preferably contains an organic solvent as the main component. Specifically, it is preferable that the solvent has high solubility in the polyester, which is the main component, and has no residual solvent and quick-drying properties. From this viewpoint, organic solvents with a boiling point of 100°C or less are preferred. Examples of preferred organic solvents include ester-based solvents such as ethyl acetate, propyl acetate, and butyl acetate; ketone-based solvents such as acetone and 2-butanone; ether-based solvents such as tetrahydrofuran; aliphatic solvents such as hexane and cyclohexane; and aromatic solvents such as toluene. When alcohol-based solvents or water are mixed, it is preferable to minimize their amount because an isocyanate compound is also used as a curing agent.

[0054] <Water-based barrier coating agent (WB)> The aqueous barrier coating agent (WB) contains a resin (WB-A) and an aqueous solvent (WB-B), and the resin preferably contains a vinyl alcohol polymer (WB-A1), more preferably a vinyl alcohol polymer having a degree of saponification of 90% or more. Furthermore, the aqueous barrier coating agent (WB) further preferably contains a resin (WB-A) containing a vinyl alcohol polymer having a degree of saponification of 90% or more and a polyalkyleneimine (WB-A2), and an aqueous solvent (WB-B).

[0055] (Vinyl alcohol polymer (WB-A1)) The vinyl alcohol polymer (WB-A1) may be a hydrolyzate (WB-A1-1) of a homopolymer or copolymer of a vinyl ester (WB-a1) obtained by a known, commonly used method, or a reaction product (WB-A1-2) of a hydrolyzate of a homopolymer or copolymer of a vinyl ester (WB-a1) with an aldehyde obtained by a known, commonly used method.

[0056] Examples of the vinyl ester (WB-a1) include vinyl formate, vinyl acetate, vinyl propionate, vinyl butyrate, vinyl isobutyrate, vinyl pivalate, vinyl versatate, vinyl caproate, vinyl caprylate, vinyl laurate, vinyl palmitate, vinyl stearate, vinyl oleate, and vinyl benzoate, and these can be used alone or in combination of two or more. Of these, vinyl acetate is preferably used.

[0057] Examples of the polymerizable compound (WB-a2) copolymerizable with the vinyl ester (WB-a1) include ethylene, propene, 1-butene, isobutylene, 1,3-butadiene, isopropenyl acetate, 2-propenyl acetate, 3,4-diacetoxy-1-butene, 2,2-dialkyl-4-vinyl-1,3-dioxolane such as 2,2-dimethyl-4-vinyl-1,3-dioxolane, 3,4-dihydroxy-1-butene, 3,4-diacyloxy-1-butene, 3-acyloxy-4-hydroxy-1-butene, 4-acyloxy-3-hydroxy-1-butene, 3,4-diacyloxy-2-methyl-1-butene, 4,5-dihydroxy-1-pentene, 4,5-diacyloxy-1- Examples of the alkyl acrylate include pentene, 4,5-dihydroxy-3-methyl-1-pentene, 4,5-diacyloxy-3-methyl-1-pentene, 5,6-dihydroxy-1-hexene, 5,6-diacyloxy-1-hexene, and other 3,4-diacyloxy-1-butenes, styrene, α-methylstyrene, vinyl chloride, acrylonitrile, maleic anhydride, methyl acrylate, methyl methacrylate, N-vinyl-N-methylformamide, vinylacetamide, N-vinylformamide, N-(hydroxymethyl)-N-vinylformamide, hydroxyethyl acrylate, methyl vinyl ketone, and diacetone acrylamide, and these may be used alone or in combination of two or more. Among these, ethylene, isopropenyl acetate, and 2-propenyl acetate are preferred.

[0058] When the vinyl ester (WB-a1) and the polymerizable compound (WB-a2) are used in combination, the amounts used can be adjusted as appropriate. However, from the viewpoint of gas barrier properties, the amount of the polymerizable compound (WB-a2) blended is preferably kept to 60 mol % or less, and more preferably 25 mol % or less, of the total amount of the vinyl ester (WB-a1) and the polymerizable compound (WB-a2).

[0059] The degree of polymerization of the vinyl ester polymer, which is the precursor of the vinyl alcohol polymer (A1-1) or (A-2), is not particularly limited, but is, for example, 200 to 10,000, more preferably 300 to 5,000, and even more preferably 400 to 3,000. This allows the production of a coating agent with an excellent balance between gas barrier properties and coatability.

[0060] Aldehydes used for acetalization include aliphatic aldehydes such as formaldehyde, acetaldehyde, propylaldehyde, butylaldehyde, octylaldehyde, and dodecylaldehyde; alicyclic aldehydes such as cyclohexanecarbaldehyde; aromatic aldehydes such as benzaldehyde, naphthaldehyde, anthraldehyde, phenylacetaldehyde, tolualdehyde, dimethylbenzaldehyde, cuminaldehyde, and benzylaldehyde; cyclohexene aldehyde, and dimethylcyclohexene aldehyde. Examples of suitable aldehydes include unsaturated aldehydes such as acrolein; aldehydes having a heterocycle such as furfural and 5-methylfurfural; hemiacetals such as glucose and glucosamine; and aldehydes having an amino group such as 4-aminobutyraldehyde. In addition, aliphatic ketones such as 2-propanone, methyl ethyl ketone, 3-pentanone, and 2-hexanone; alicyclic ketones such as cyclopentanone and cyclohexanone; and aromatic ketones such as acetophenone and benzophenone can be used singly or in combination of two or more.

[0061] As the acid catalyst used in the acetalization, conventionally known organic or inorganic acids such as acetic acid, paratoluenesulfonic acid, nitric acid, sulfuric acid, and hydrochloric acid can be used.

[0062] Specific examples of suitable vinyl alcohol polymers (WB-A1) include polyvinyl alcohol, ethylene vinyl alcohol, polyvinyl butyral, and vinyl alcohol-butenediol copolymers. One of these may be used alone, or two or more may be used in combination. From the viewpoint of the balance between gas barrier properties and adhesion, it is more preferable to use either polyvinyl alcohol or ethylene vinyl alcohol, or both.

[0063] The vinyl alcohol polymer (WB-A1-1) preferably has a saponification degree of 90% or more, more preferably 95% or more, because it has excellent gas barrier properties. It may also be 100%. The saponification degree can be measured by FTIR using, for example, a Nicolet 5700 FTIR spectrometer controlled by OMNIC software. The vinyl alcohol polymer (WB-A1-2) is more preferably one obtained by acetalizing a precursor having a saponification degree of 95% or more.

[0064] (Polyalkyleneimine (WB-A2)) The aqueous barrier coating agent (WB) preferably further contains a polyalkyleneimine (WB-A2) as the resin (WB-A). The polyalkyleneimine (WB-A2) is a resin having a polyalkyleneimine skeleton and is obtained by polymerizing one or more alkyleneimines (e.g., ethyleneimine, propyleneimine) by a conventional method. The combined use of the vinyl alcohol polymer (WB-A1) and the polyalkyleneimine (WB-A2) is preferred because it can improve adhesion to olefinic substrates while maintaining the gas barrier properties of the coating agent.

[0065] The polyalkyleneimine (WB-A2) may be a linear polyalkyleneimine having a linear polyalkyleneimine chain, or a branched polyalkyleneimine having a branched polyalkyleneimine chain. Examples of the polyalkyleneimine (WB-A2) include polyethyleneimine and polypropyleneimine. The polyalkyleneimine (WB-A2) may have a substituent (e.g., a hydroxypropyl group or a hydroxyethyl group) introduced into at least some of the nitrogen atoms of the polyalkyleneimine chain. Those modified with organometallic compounds such as tetraisopropyl titanate, tetra-normal butyl titanate, butyl titanate dimer, tetra(2-ethylhexyl) titanate, tetramethyl titanate, polyhydroxytitanium stearate, titanium bisacetylacetonate, titanium tetraacetylacetonate, polytitanium acetylacetonate, titanium octylene glycolate, titanium ethylacetoacetate, titanium lactate, titanium triethanolaminate, and titanium stearate may also be used, and two or more types of polyalkyleneimines can also be used in combination.

[0066] The polyalkyleneimine (WB-A2) is believed to contribute to improving the adhesion between the vinyl alcohol polymer (WB-A1) and the olefin film through its amino groups (NHR groups, NH2 groups) and ethylene groups. Because of its effectiveness in improving adhesion, it is preferable for the polyalkyleneimine (WB-A2) to contain a branched polyalkyleneimine. The degree of branching of the polyalkyleneimine (WB-A2) can be expressed by the proportion of primary, secondary, and tertiary amino groups possessed by the polyalkyleneimine (WB-A2). While this can be appropriately adjusted depending on the vinyl alcohol polymer (WB-A1) used and its amount, it is preferable to use a polyalkyleneimine (WB-A2) with a proportion of primary amino groups of 20 to 40%, a proportion of secondary amino groups of 30 to 60%, and a proportion of tertiary amino groups of 20 to 35%. The proportions of primary, secondary and tertiary amine groups contained in the polyalkyleneimine (WB-A2) can be measured by 13C-NMR spectroscopy. The branched polyalkyleneimine is preferably a branched polyethyleneimine.

[0067] The number-average molecular weight of the polyalkyleneimine (WB-A2) is preferably 5,000 or more, more preferably 9,000 or more, and even more preferably 50,000 or more, because it has excellent adhesive properties. There is no particular upper limit, but an example is 100,000 or less. The number-average molecular weight of the polyalkyleneimine (WB-A2) was measured by GPC (gel permeation chromatography) using pullulan as a standard substance.

[0068] In the aqueous barrier coating agent (WB), the blending amount of the polyalkyleneimine (WB-A2) is preferably 1% by mass or more and 90% by mass or less of the total amount of the vinyl alcohol polymer (WB-A1) and the polyalkyleneimine (WB-A2). This allows the aqueous barrier coating agent (WB) to maintain its gas barrier properties while more reliably improving its adhesion to olefin-based substrates. A blending amount of 3% by mass or more and 50% by mass or less is more preferred.

[0069] The aqueous barrier coating agent (WB) may contain a resin (WB-A3) other than the vinyl alcohol polymer (WB-A1) and the polyalkyleneimine (WB-A2). Examples of such resins (WB-A3) include cellulose resins, polyesters, polyurethanes, vinyl resins such as homopolymers or copolymers of olefins or styrenes, acrylic resins, epoxy resins, amide resins, natural rubber, and composites thereof (e.g., core-shell resins). These resins may be used singly or in combination. Since excessive amounts of resin (WB-A3) can degrade gas barrier properties, the amount of resin (WB-A3) is preferably kept to 10% by mass or less of the total amount of resin (WB-A) (the total amount of vinyl alcohol polymer (WB-A1), polyalkyleneimine (WB-A2), and resin (WB-A3)), more preferably 5% by mass or less, and even more preferably 1% by mass or less. Alternatively, the amount may be 0% by mass.

[0070] The amount of the resin (WB-A) in the aqueous barrier coating agent (WB) can be adjusted appropriately depending on the coating suitability and the like.

[0071] (Water-based solvent (WB-B)) The aqueous solvent (WB-B) may be water, a water-soluble organic solvent that dissolves in water, or the like. As the water, pure water or ultrapure water such as ion-exchanged water, ultrafiltered water, reverse osmosis water, or distilled water may be used. From the viewpoint of long-term storage, it is preferable to use water that has been sterilized by ultraviolet irradiation or the addition of hydrogen peroxide, for example, in order to prevent the growth of mold or bacteria.

[0072] Examples of water-soluble organic solvents include glycols such as ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, propylene glycol, polyethylene glycol, and polypropylene glycol; diols such as butanediol, pentanediol, and hexanediol; glycol esters such as propylene glycol laurate; diethylene glycol ethers such as diethylene glycol monoethyl, diethylene glycol monobutyl, diethylene glycol monohexyl, and carbitol; glycol ethers such as cellosolves containing propylene glycol ether, dipropylene glycol ether, and triethylene glycol ether; alcohols such as methanol, ethanol, isopropyl alcohol, 1-propanol, 1-butanol, 2-butanol, butyl alcohol, and pentyl alcohol; lactones such as sulfolane, esters, ketones, and γ-butyrolactone; lactams such as N-(2-hydroxyethyl)pyrrolidone; and various other solvents known as aqueous organic solvents, such as glycerin and its polyalkylene oxide adducts. These aqueous organic solvents can be used alone or in combination.

[0073] (Additive (WB-C)) The aqueous barrier coating agent (WB) may further contain an additive (WB-C) in addition to the resin (WB-A) and aqueous solvent (WB-B). Examples of the additive (WB-C) include layered inorganic compounds, crosslinking agents capable of reacting with functional groups in the vinyl alcohol polymer (WB-A1) or polyalkyleneimine (WB-A2), inorganic fillers, antifoaming agents, stabilizers (antioxidants, heat stabilizers, UV absorbers, etc.), plasticizers, antistatic agents, lubricants, antiblocking agents, colorants, leveling agents, etc.

[0074] Examples of layered inorganic compounds include natural smectites such as montmorillonite, synthetic smectites, natural mica, synthetic mica, hydrotalcite, and talc, as well as lipophilic-treated smectites and lipophilic synthetic mica, which are obtained by organically treating these compounds. The use of layered inorganic compounds improves the gas barrier properties of the coating agent, but tends to reduce adhesion to olefin-based substrates. The amount of layered inorganic compound blended is preferably 10 to 100 parts by mass per 100 parts by mass of resin (WB-A), as this provides an excellent balance between gas barrier properties and adhesion.

[0075] Examples of crosslinking agents include aldehydes such as formalin and glutaraldehyde; acetals such as diacetalized products of glutaraldehyde; aliphatic polyisocyanates such as hexamethylene diisocyanate and its derivatives (adduct, nurate, biuret, etc.), aromatic aliphatic polyisocyanates such as xylylene diisocyanate and its derivatives, aromatic polyisocyanates such as toluene diisocyanate and its derivatives, and isocyanates such as urethane prepolymers which are reaction products of these isocyanates with polyols; epoxies; titanium, silicon, aluminum, zirconium, Examples of suitable isocyanates include organometallic compounds of boron or the like with alkoxides or the like; methylol ureas such as methylol urea and methylol melamine; carboxyl group-containing polymers such as polyacrylic acid polymers and maleic anhydride polymers; carbodiimides such as p-phenylene-bis(2,6-xylylcarbodiimide), tetramethylene-bis(t-butylcarbodiimide), and cyclohexane-1,4-bis(methylene-t-butylcarbodiimide); boric acid; and titanium lactate. As the isocyanates, blocked isocyanates prepared using known blocking agents or emulsion-type isocyanates may be used.

[0076] The use of a crosslinking agent improves adhesion to olefin-based substrates, but tends to reduce gas barrier properties. The amount of crosslinking agent blended is preferably 5 to 50 parts by mass per 100 parts by mass of resin (WB-A), as this provides an excellent balance between gas barrier properties and adhesion.

[0077] Ink layer (B) In the present invention, the ink layer (B) is obtained by applying and drying a liquid ink composition containing a polyurethane resin, in which the amine value of the non-volatile component of the polyurethane resin is 0.1 mgKOH / g to 10 mgKOH / g.

[0078] [Liquid ink composition] The liquid ink composition contains a polyurethane resin as a binder resin, and the amine value of the non-volatile components of the polyurethane resin is 0.1 mgKOH / g to 10 mgKOH / g. Each component will be described in detail below.

[0079] (binder resin) In this specification, the term "binder resin" refers to a binder resin contained in an ink or ink composition. The binder resin may be in a state of being dissolved in a solvent or in an emulsion state. The properties and characteristics of at least the polyurethane resin contained as the binder resin in a liquid ink composition are described below.

[0080] <Polyurethane resin> Polyurethane resin is a general term for polymeric compounds having a urethane bond (-NHCOO-), and in the present invention, it is made from a reaction product obtained by reacting (crosslinking and curing reaction) polyester polyol with polyisocyanate. The polyurethane resin may further contain other polyols in addition to the polyester polyol and polyisocyanate, or may be a reaction product of polyester polyol, polyisocyanate and other polyol. The polyurethane resin can be prepared by, for example, reacting polypropylene glycol and a polyol to be used in combination with a diisocyanate compound in a ratio such that the isocyanate group is in excess to obtain a prepolymer having an isocyanate group at its terminal; and then dissolving the prepolymer in a suitable solvent, i.e., a solvent typically used as a solvent for non-toluene gravure inks (e.g., ester solvents such as ethyl acetate, propyl acetate, and butyl acetate; ketone solvents such as acetone, methyl ethyl ketone, and methyl isobutyl ketone; alcohol solvents such as methanol, ethanol, isopropyl alcohol, and n-butanol; methylcyclohexane, ethyl The polyurethane resin can be produced by a two-stage process, which involves reacting the prepolymer with a chain extender such as a diamine and / or a terminal blocking agent such as a monoamine in a hydrocarbon solvent such as cyclohexane or a mixture thereof, or a single-stage process, which involves reacting polypropylene glycol and a co-polyol with a diisocyanate compound in such a ratio that the isocyanate groups in the diisocyanate compound are in excess to obtain a prepolymer having terminal isocyanate groups, and then reacting the prepolymer with a chain extender such as a diamine and / or a terminal blocking agent such as a monoamine in a suitable solvent. Among these processes, the two-stage process is preferred for obtaining a uniform polyurethane resin. When producing a polyurethane resin by the two-stage process, it is preferable to react the chain extender and / or terminal blocking agent so that the total amino groups (equivalent ratio) of the chain extender and / or terminal blocking agent is 1 / 0.9 to 1.3. If the equivalent ratio of isocyanate groups to amino groups is less than 1 / 1.3, the chain extender and / or end-capping agent may remain unreacted, causing the polyurethane resin to yellow or emitting an odor after printing.

[0081] The chain extender may be any compound commonly used in the production of polyurethane resins, and examples thereof include diamines such as ethylenediamine, propylenediamine, hexamethylenediamine, diethylenetriamine, triethylenetetramine, isophoronediamine, and dicyclohexylmethane-4,4'-diamine; and amines having a hydroxyl group in the molecule such as 2-hydroxyethylethylenediamine, 2-hydroxyethylpropanyldiamine, 2-hydroxyethylpropylenediamine, di-2-hydroxyethylethylenediamine, di-2-hydroxyethylenediamine, di-2-hydroxyethylpropylenediamine, 2-hydroxypropylethylenediamine, di-2-hydroxypropylethylenediamine, and di-2-hydroxypropylethylenediamine. These chain extenders may be used alone or in combination of two or more.

[0082] The terminal blocking agent may be any compound intended for terminating the reaction, and a monovalent active hydrogen compound may also be used. Examples of such compounds include monoamines, such as mono- and di-alkylamines such as butylamine, octylamine, diethylamine, and di-n-butylamine, and alcohols such as ethanol and isopropyl alcohol. Furthermore, when it is particularly desired to introduce a carboxyl group into the polyurethane resin, amino acids such as glycine and L-alanine can be used as reaction terminators. These terminal blocking agents may be used alone or in combination of two or more.

[0083] In the present invention, the amine value of the non-volatile components of the polyurethane resin is 0.1 mgKOH / g to 10 mgKOH / g, i.e., 0.1 mgKOH / g or more and 10 mgKOH / g or less. The amine value of the non-volatile components of the polyurethane resin is preferably 0.15 mgKOH / g or more, and more preferably 3 mgKOH / g or more. Furthermore, the amine value of the non-volatile components of the polyurethane resin is preferably 9 mgKOH / g or less, more preferably 7 mgKOH / g or less, and even more preferably 5 mgKOH / g or less. By ensuring that the amine value of the non-volatile components of the polyurethane resin is 0.1 mgKOH / g or more, the adhesion between an ink layer made of a liquid ink composition containing the polyurethane resin and an adjacent layer can be improved. Furthermore, by ensuring that the amine value of the non-volatile components of the polyurethane resin is 10 mgKOH / g or less, the liquid ink composition containing the polyurethane resin can be made to have excellent two-component stability.

[0084] The weight-average molecular weight (Mw) of the polyurethane resin is preferably 8,000 or more, more preferably 15,000 or more. Meanwhile, the weight-average molecular weight (Mw) of the polyurethane resin is preferably 100,000 or less, more preferably 80,000 or less. The upper and lower limits can be arbitrarily combined. A weight-average molecular weight (Mw) of 8,000 or more provides excellent blocking resistance for the resulting ink composition, and excellent strength and oil resistance of the printed film, and is also preferred from the viewpoint of adhesion. Meanwhile, a weight-average molecular weight (Mw) of 100,000 or less provides appropriate viscosity for the resulting liquid ink composition, excellent gloss for the printed film, and is also preferred from the viewpoint of blocking resistance and laminate strength. In the present invention, the urethane bond concentration of the polyurethane resin is preferably 0.30 mmol / g or more, and more preferably 0.40 mmol / g or more. Meanwhile, the urethane bond concentration of the polyurethane resin is preferably 2.0 mmol / g or less, and more preferably 1.8 mmol / g or less. A urethane bond concentration of 0.30 mmol / g or more is preferred from the viewpoint of polyethylene extrusion lamination strength when printed on OPP film. Meanwhile, a urethane bond concentration of 2.0 mmol / g or less is preferred from the viewpoints of polyurethane resin raw material cost, ink viscosity, and flexibility of the ink coating on the film (adaptability to film deformation). The urea bond concentration of the polyurethane resin is preferably 0.30 mmol / g or more, more preferably 0.50 mmol / g or more. On the other hand, the urea bond concentration of the polyurethane resin is preferably 2.0 mmol / g or less, more preferably 1.5 mmol / g or less. A urea bond concentration of 0.50 mmol / g or more is preferred from the viewpoint of improving the durability of the final liquid ink composition. On the other hand, a urea bond concentration of 2.0 mmol / g or less is preferred from the viewpoint of solubility in organic solvents.

[0085] The urethane bond concentration can be calculated using the following formula (2). Urethane bond concentration = {(W1 × OH1 + W2 × OH2 + + W i ×OH i )×1000} / (56100×S) Equation (2) In equation (2), the following are true: W1: Weight of polyol 1 OH1: hydroxyl value of polyol 1 W2: Weight of polyol 2 OH2: hydroxyl value of polyol 2 W i : weight of polyol i OH i : hydroxyl value of polyol i S: Weight of non-volatile components of urethane resin

[0086] The urea binding concentration can be calculated using the following formula (3). Urea bond concentration={(X1 / M1+X2 / M2+···+X i / M i )×2-(W1×OH1+W2×OH2+···+W i ×OH i ) / 56100}×1000 / S Equation (3) In formula (3), the symbols are as follows: X1: Weight of diisocyanate compound 1 M1: Molecular weight of diisocyanate compound 1 X2: Weight of diisocyanate compound 2 M2: Molecular weight of diisocyanate compound 2 X i : Weight of diisocyanate compound i M i : Molecular weight of diisocyanate compound i W1: Weight of polyol 1 OH1: hydroxyl value of polyol 1 W2: Weight of polyol 2 OH2: hydroxyl value of polyol 2 W i : weight of polyol i OH i : hydroxyl value of polyol i S: Weight of non-volatile components of urethane resin

[0087] The content of the polyurethane resin used in the liquid ink composition in the ink, for example, in a resin solution with a non-volatile content of 30%, is preferably 4% by weight or more of the total weight of the ink in order to ensure sufficient adhesion of the ink to the substrate, and 50% by weight or less in order to achieve appropriate ink viscosity and work efficiency during ink production and printing, and more preferably in the range of 6% by weight or more and 40% by weight or less. The hydroxyl value of the polyurethane resin is preferably 10 mgKOH / g or less, more preferably 3 mgKOH / g or less, and even more preferably 0 mgKOH / g. A hydroxyl value of 10 mgKOH / g or less can prevent deterioration of the ink layer's substrate adhesion and water abrasion resistance, and can improve two-component stability. Here, the acid value can be determined by the number of mg of KOH required when titrating the COOH groups contained in 1 g of polyurethane resin using the potassium hydroxide method, and the weight average molecular weight can be measured by gel permeation chromatography (GPC). The hydroxyl value can be measured in accordance with the method described in JIS K0070.

[0088] The polyurethane resin may be a compound in which, in addition to polyisocyanate and polyester polyol, other polyols are used as reaction raw materials. Each component of the reaction raw materials will be described in detail below.

[0089] The polyisocyanate may be any compound having two or more isocyanate groups, and is preferably a diisocyanate compound, such as various known aromatic diisocyanates, aliphatic diisocyanates, and alicyclic diisocyanates that are commonly used in the production of polyurethane resins. For example, 1,5-naphthylene diisocyanate, 4,4'-diphenylmethane diisocyanate, 4,4'-diphenyldimethylmethane diisocyanate, 4,4'-dibenzyl isocyanate, dialkyldiphenylmethane diisocyanate, tetraalkyldiphenylmethane diisocyanate, 1,3-phenylene diisocyanate, 1,4-phenylene diisocyanate, tolylene diisocyanate, butane-1,4-diisocyanate, hexamethylene diisocyanate, isopropylene diisocyanate, methylene diisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, lysine diisocyanate, cyclohexane-1 Examples of suitable diisocyanate compounds include 4,4-diisocyanate, xylylene diisocyanate, isophorone diisocyanate, dimeryl diisocyanate, dicyclohexylmethane-4,4'-diisocyanate, 1,3-bis(isocyanatomethyl)cyclohexane, methylcyclohexane diisocyanate, norbornane diisocyanate, m-tetramethylxylylene diisocyanate, 4,4-diphenylmethane diisocyanate, tolylene diisocyanate, bis-chloromethyl-diphenylmethane-diisocyanate, 2,6-diisocyanato-benzyl chloride, and dimer diisocyanate in which the carboxyl groups of dimer acid are converted to isocyanate groups. These diisocyanate compounds can be used alone or in combination of two or more.

[0090] <Polyester polyol> The polyester polyol is preferably a polyester polyol obtained by dehydration condensation or polymerization of a low-molecular-weight polyol and a polycarboxylic acid or an anhydride thereof. The polyester polyol can further increase laminate strength by introducing an ester group to increase cohesive energy.

[0091] As the low-molecular-weight polyol, various known compounds having two or more hydroxyl groups that are generally used in the production of polyester polyols can be used, and one or more of them may be used in combination. Specific examples include glycols such as ethylene glycol, propylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, diethylene glycol, triethylene glycol, tetraethylene glycol, dipropylene glycol, tripropylene glycol, 1,4-cyclohexanediol, and 1,4-cyclohexanedimethanol; 2-methyl-1,5-pentanediol, 3-methyl-1,5-pentanediol, 1,2-butanediol, 1,3-butanediol, and 2-butyl-2-ethyl-1,3 Examples of suitable branched glycols include 2-propanediol, 1,2-propanediol, 2-methyl-1,3-propanediol, neopentyl glycol, 2-isopropyl-1,4-butanediol, 2,4-dimethyl-1,5-pentanediol, 2,4-diethyl-1,5-pentanediol, 2-ethyl-1,3-hexanediol, 2-ethyl-1,6-hexanediol, 3,5-heptanediol, and 2-methyl-1,8-octanediol; and glycerin, trimethylolpropane, trimethylolethane, pentaerythritol, and sorbitol.

[0092] The polycarboxylic acid or anhydride thereof may be any of various known polycarboxylic acids commonly used in the production of polyester polyols, and one or more of these may be used in combination. Specific examples include polycarboxylic acids having 6 or less carbon atoms and two or more carboxyl groups, such as oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, fumaric acid, maleic acid, and anhydrides of these acids; aromatic dicarboxylic acids, such as phthalic acid, isophthalic acid, terephthalic acid, and anhydrides of these acids; aliphatic dicarboxylic acids, such as pimelic acid, suberic acid, azelaic acid, sebacic acid, and dimer acid; tricarboxylic acids, such as trimellitic acid and anhydrides thereof; benzenetetracarboxylic acid, benzenepentacarboxylic acid, benzenehexacarboxylic acid, and anhydrides of these acids.

[0093] The polyester polyol may be any of various known polyester polyols commonly used in the production of polyurethane resins, such as polyester polyols obtained by ring-opening polymerization of cyclic ester compounds, for example, lactones such as polycaprolactone, polyvalerolactone, and poly(β-methyl-γ-valerolactone), and one or more of these may be used in combination.

[0094] The number average molecular weight of the polyester polyol is preferably in the range of 500 to 8,000, more preferably in the range of 800 to 7,000, and even more preferably in the range of 900 to 6,000.

[0095] <Other polyols> Examples of the other polyols include polyether polyols and polyols used in combination.

[0096] <<Polyether polyol>> The polyether polyol may be any of various known polyether polyols commonly used in the production of polyurethane resins, and may be used alone or in combination of two or more. Examples include polyether polyols of polymers or copolymers of methylene oxide, ethylene oxide, propylene oxide, tetrahydrofuran, and the like. Specifically, known, general-purpose polyether polyols such as polyethylene glycol, polypropylene glycol, and polytetramethylene glycol may be used. The inclusion of a polyether polyol significantly improves adhesion, particularly on high-performance barrier films, resulting in excellent blocking resistance and laminate strength. The polyether polyol preferably has a number average molecular weight of 100 to 3500. The polyether polyol is preferably contained as a residue in the polyurethane resin in an amount of 1 to 40% by mass.

[0097] <<Polyol used in combination>> As the polyol to be used in combination, various known polyols generally used in the production of polyurethane resins can be used, and one or more of them may be used in combination. Examples of the polyol include ethylene glycol, 1,2-propanediol, 1,3-propanediol, 2-methyl-1,3 propanediol, 2-ethyl-2-butyl-1,3 propanediol, 1,3-butanediol, 1,4-butanediol, neopentyl glycol, pentanediol, 3-methyl-1,5 pentanediol, hexanediol, octanediol, 1,4-butynediol, 1,4-butylenediol, diethylene glycol, triethylene glycol, dipropylene glycol, glycerin, trimethylolpropane, trimethylolethane, 1,2,6-hexanetriol, 1,2,4-butanetriol, sorbitol, and pentaerythritol. Examples of suitable polyols include saturated or unsaturated low-molecular-weight polyols (1); polycarbonate polyols (2) obtained by reacting the above-mentioned low-molecular-weight polyols with, for example, dimethyl carbonate, diphenyl carbonate, ethylene carbonate, phosgene, etc.; polybutadiene glycols (3); glycols (4) obtained by adding ethylene oxide or propylene oxide to bisphenol A; and acrylic polyols (4) obtained by copolymerizing, in one molecule, one or more hydroxyethyl groups, hydroxypropyl acrylate, hydroxybutyl acrylate, etc., or their corresponding methacrylic acid derivatives, with, for example, acrylic acid, methacrylic acid, or an ester thereof.

[0098] <Other resins> The binder resin of the liquid ink composition may further contain various resins other than polyurethane resin, such as one or more resins selected from the group consisting of cellulose resins, vinyl chloride-vinyl acetate resins, polyester resins, acrylic resins, polyamide resins, rosin-modified maleic acid resins, polyvinyl butyral resins, chlorinated polyolefin resins, and ketone aldehyde resins. This can result in a liquid ink composition and ink layer that are superior in blocking resistance, adhesion, lamination suitability, scratch resistance, pigment dispersibility, fluidity, and storage (aging) stability. Examples of cellulose-based resins include cellulose acetate propionate, cellulose acetate butyrate, and other cellulose ester resins, nitrocellulose (also known as soluble cellulose), hydroxyalkyl cellulose, and carboxyalkyl cellulose. Vinyl chloride-vinyl acetate copolymer resins are not particularly limited as long as they are copolymerized with vinyl chloride and vinyl acetate. Polyester resins are not particularly limited as long as they are polyester resins obtained by reacting alcohols with carboxylic acids using a known esterification polymerization reaction. Acrylic resins are not particularly limited as long as they are copolymerized with polymerizable monomers containing (meth)acrylic acid esters as the main component. Polyamide resins are not particularly limited as long as they are thermoplastic polyamides soluble in organic solvents, such as those obtainable by polycondensation of polybasic acids and polyamines. Chlorinated polyolefin resins include, but are not limited to, chlorinated polyethylene resins and chlorinated polypropylene resins.

[0099] In the liquid ink composition, the proportion of the polyurethane resin component (non-volatile component) relative to the total non-volatile components of the binder resin (non-volatile component) is preferably 30% by mass or more and 100% by mass or less, more preferably 40 to 90% by mass, and even more preferably 50% by mass or more and 80% by mass or less. By making the proportion of the polyurethane resin component (non-volatile component) 50% by mass or more, good extrusion lamination strength can be achieved when printed on OPP film or the like.

[0100] <Chlorine content> Chlorine-based resins such as vinyl chloride-vinyl acetate copolymers and chlorinated polyolefin resins are of concern as substances that hinder packaging recycling for the following reasons (a) and (b). (a) Chlorine-based resins such as vinyl chloride can cause corrosion of equipment or piping by releasing hydrogen chloride and generating hydrochloric acid during the thermal decomposition process of recycling. (b) In thermal recycling, which reuses the energy generated when waste is incinerated, the incineration of chlorine-based resins can result in the release of environmental hormones such as dioxins. Therefore, laminating inks are required to be free of chlorine-based resins, for example. From these perspectives, the chlorine content of all nonvolatile resin components in the liquid ink composition, i.e., the resin components contained in the ink layer (B), is preferably 5% by mass or less, more preferably 1% by mass or less, and even more preferably 0% by mass. While the lower limit of the chlorine content can be said to be 0% by mass, the chlorine content may exceed 0% by mass because unavoidable amounts of chlorine may be present during the binder resin production process. By limiting the chlorine content of the resin components contained in the ink layer (B) to 5% by mass or less, the amount of chlorine gas emitted during the resin preparation into recycled pellets and the recycling process can be reduced, which is preferable from the standpoints of equipment maintenance and environmental conservation. Furthermore, from these perspectives, the liquid ink composition is particularly suitable for use as a liquid ink composition for extrusion lamination, in which the binder resin is exposed to high temperatures during recycling.

[0101] The chlorine content can be calculated from the chlorine content in all nonvolatile resin components in the liquid ink composition using the following formula. (Chlorine content contained in all resin non-volatile components in liquid ink composition) = (Chlorine content contained in all resin non-volatile components in liquid ink composition) / (mass of all resin non-volatile components in liquid ink composition)

[0102] (organic solvent) Examples of organic solvents that can be used to dissolve binder resins include acetate esters such as ethyl acetate, n-propyl acetate, and butyl acetate; alcohols such as methanol, ethanol, n- and isopropanol; ketones such as acetone and methyl ethyl ketone; polyalkylene glycols such as ethylene glycol, diethylene glycol, and propylene glycol; alkyl ethers of polyalkylene glycols; and N-methyl-2-pyrrolidone. Because film-forming materials widely used on plastic substrates require consideration for worker health and the environment, toluene-free and ketone-free organic solvents, particularly methyl ethyl ketone (MEK), are preferred. Ethyl acetate, n-propyl acetate, and isopropyl alcohol are preferred. Furthermore, in order to improve ink transferability to the substrate and prevent plate clogging, it is preferable to use a glycol ether-based solvent with a slow evaporation rate, such as propylene glycol monomethyl ether. When dispersing the binder resin and pigment in the organic solvent, a machine such as a homogenizer can be used as needed.

[0103] The liquid ink composition may contain a colorant. Examples of colorants include organic and inorganic pigments and dyes commonly used in inks, paints, and recording materials. Examples of organic pigments include azo-based, phthalocyanine-based, anthraquinone-based, perylene-based, perinone-based, quinacridone-based, thioindigo-based, dioxazine-based, isoindolinone-based, quinophthalone-based, azomethine azo-based, dicetpyrrolopyrrole-based, and isoindoline-based pigments. It is preferable to use copper phthalocyanine for indigo inks and CI Pigment No. 83 for transparent yellow inks in terms of cost and lightfastness.

[0104] Examples of inorganic pigments include carbon black, titanium oxide, zinc oxide, zinc sulfide, barium sulfate, calcium carbonate, chromium oxide, silica, red iron oxide, aluminum, and mica. Furthermore, a lustrous pigment (Metashine; Nippon Sheet Glass Co., Ltd.) made of glass flakes or aggregate flakes as a base material coated with a metal or metal oxide can also be used. From the standpoints of cost and coloring power, it is preferable to use titanium oxide for white ink, carbon black for black ink, aluminum for gold and silver ink, and mica for pearl ink. Aluminum is available in powder or paste form, but it is preferably used in paste form from the standpoints of handleability and safety. Whether leafing or non-leafing is used is determined appropriately from the standpoints of brightness and density. The colorant is preferably contained in an amount sufficient to ensure the density and coloring strength of the ink, i.e., 1 to 50% by weight of the total weight of the ink. The colorant may be used alone or in combination of two or more types.

[0105] (Other additives) The liquid ink composition may optionally contain various additives, such as film-forming aids, crosslinking agents, curing accelerators, plasticizers, antistatic agents, waxes, light stabilizers, flow modifiers, dyes, leveling agents, rheology control agents, UV absorbers, antioxidants, photocatalytic compounds, inorganic pigments, organic pigments, and extender pigments. Furthermore, to stably disperse pigments in organic solvents, the resins mentioned above can be used alone, but dispersants can also be used in combination to further stabilize the pigment dispersion. Examples of dispersants include anionic, nonionic, cationic, and amphoteric surfactants. Examples include comb-structured polymers in which polyethyleneimine is polyester-added, and alkylamine derivatives of α-olefin maleic acid polymers. Specific examples include the Solsperse series (Lubrizol), the Ajisper series (Ajinomoto), and the Homogenol series (Kao). The BYK series (BYK-Chemie) and the EFKA series (EFKA) can also be used as appropriate. The dispersant is preferably contained in the ink in an amount of 0.05% by weight or more based on the total weight of the ink from the viewpoint of storage stability of the ink, and 5% by weight or less from the viewpoint of lamination suitability, and more preferably in the range of 0.1 to 2% by weight. The presence of a dispersant improves pigment sedimentation and stability over time, and also improves two-component stability when a curing agent is used in combination with the ink, for example.

[0106] Among the additives, emulsifiers and leveling agents may cause a decrease in the durability of the resulting film, etc., so when high durability is required for the film, etc., it is preferable to use them in an amount of 5 mass% or less based on the total amount of the liquid ink composition.

[0107] (silica) The liquid ink composition may contain silica. "Silica" refers to silicon dioxide (SiO2) or a general term for a substance composed of silicon dioxide. Silica may be crystalline or amorphous. It may also be silica contained in natural minerals or may be added to dioctahedral smectite. Crystalline silica refers to a solid substance having a crystalline structure (atoms, ions, or molecules constituting a crystal are arranged with three-dimensional periodicity to form a spatial lattice). Amorphous silica refers to a solid substance in which atoms (or molecules) are aggregated without forming crystals with a regular spatial arrangement. Specific examples of "silica" include silicon dioxide, epoxy-modified silicone, amino-modified silicone, and polyester-modified silicone. The shape of the "silica" is not particularly limited, but particulate silica (hereinafter also referred to as silica particles) is preferred.

[0108] -Particle size distribution- The preferred particle size distribution of silica is determined using the volume-based particle size distribution measured using a laser diffraction particle size analyzer. The cumulative 90% particle size (D90) of the volume-based particle size distribution of silica is preferably 3 μm or more, more preferably 4 μm or more, and even more preferably 5 μm or more. The cumulative 90% particle size (D90) is preferably 50 μm or less, more preferably 40 μm or less, and even more preferably 30 μm or less. Similarly, the cumulative 50% particle size (D50) of the volume-based particle size distribution of silica is preferably 1 μm or more, more preferably 32 μm or more, and even more preferably 3 μm or more. The cumulative 50% particle size (D50) is preferably 30 μm or less, more preferably 20 μm or less, and even more preferably 10 μm or less. Furthermore, the cumulative 10% particle size (D10) of the volume-based particle size distribution of the silica is preferably 1 μm or more, more preferably 1.5 μm or more, and even more preferably 2 μm or more. The cumulative 10% particle size (D10) of the volume-based particle size distribution of the silica is preferably 10 μm or less, more preferably 5 μm or less, and even more preferably 4 μm or less. The particle size distribution of silica based on volume should preferably have a cumulative 50% particle size (D50) of 1 μm or more and 10 μm or less, and the index (D90-D10) / D50, calculated by taking the cumulative 90% particle size (D90), cumulative 50% particle size (D50), and cumulative 10% particle size (D10) of the particle size distribution, should be less than 2.0 (i.e., (D90-D10) / D50<2.0), more preferably less than 1.5, and even more preferably less than 1.0. Since the ink layer on a laminate film is generally about 1 μm thick, a liquid ink composition with silica particles of a size equal to or greater than this thickness will have excellent blocking resistance. Furthermore, the index (D90-D10) / D50 indicates the uniformity of particle size; a smaller value indicates less variation in the particle size of the powder in the measured system. When such particulate substances are incorporated into the liquid ink composition, the surface of the ink layer containing the liquid ink composition becomes rough, which results in an increase in the adhesive area with the extruded melt layer or the like that comes into contact with the ink layer, thereby improving strength, which is preferable.

[0109] The components described above can be mixed in any desired ratio, but the content of the polyurethane resin component (non-volatile component) in the liquid ink composition is preferably 5% by mass or more, more preferably 10% by mass or more, and even more preferably 15% by mass or more, based on the total non-volatile components of the liquid ink composition. It is also preferably 95% by mass or less, more preferably 90% by mass or less, and even more preferably 80% by mass or less. By making the content of the polyurethane resin component (non-volatile component) 15% by mass or more, good polyethylene extrusion lamination strength is achieved when printed on a laminate film, and particularly, more suitable strength is achieved with OPP film.

[0110] Furthermore, in the liquid ink composition, the content of the binder resin (non-volatile component) is preferably 5% by mass or more, more preferably 10% by mass or more, and even more preferably 15% by mass or more, based on the total non-volatile components of the liquid ink composition. It is also preferably 95% by mass or less, preferably 90% by mass or less, and even more preferably 80% by mass or less. By setting the content of the binder resin (non-volatile component) to 15% by mass or more, good pigment dispersion stability and coating film properties are exhibited. On the other hand, by setting the content of the binder resin (non-volatile component) to 80% by mass or less, good print color density is exhibited.

[0111] When silica is added to the liquid ink composition, the content of the silica is preferably 0.1% by mass or more, more preferably 0.5% by mass or more, and even more preferably 1.0% by mass or more, based on the total non-volatile components of the liquid ink composition. It is also preferably 7.0% by mass or less, preferably 6.5% by mass or less, and even more preferably 6.0% by mass or less. Adding a specific silica within the above range increases the roughness of the ink surface layer, increasing the contact area with the extruded molten layer and resulting in increased extrusion lamination strength. Furthermore, having a moderate surface roughness can also suppress poor appearance after dry lamination and non-solvent lamination, thereby achieving both extrusion lamination strength and good appearance in dry and non-solvent lamination.

[0112] (Method for producing liquid ink composition) The liquid ink composition can be produced by dissolving and / or dispersing a resin, a colorant, etc. in a solvent. Specifically, the liquid ink composition can be produced by dispersing a pigment, etc. in an organic solvent with a resin to produce a pigment dispersion, and then blending other compounds, etc., into the obtained pigment dispersion as needed.

[0113] (Distribution method) The particle size distribution of the pigment in the pigment dispersion can be adjusted by appropriately adjusting the size of the grinding media of the disperser, the packing ratio of the grinding media, the dispersion treatment time, the discharge speed of the pigment dispersion, the viscosity of the pigment dispersion, etc. As the disperser, commonly used ones such as a roller mill, a ball mill, a pebble mill, an attritor, a sand mill, etc. can be used. If the ink contains air bubbles or unexpectedly large particles, these will degrade the quality of the printed matter, so it is preferable to remove them by filtration, etc. Any conventional filter can be used.

[0114] The liquid ink composition described above is excellent in all of the properties of blocking resistance, adhesion to substrates, and two-component stability. Furthermore, when this liquid ink composition is used for extrusion lamination, it exhibits excellent extrusion lamination strength, making it suitable for use in extrusion lamination.

[0115] The liquid ink composition can be applied to a substrate using a known printing method such as gravure printing, flexographic printing, etc. In addition to the gravure printing and flexographic printing described above, known printing methods include, for example, a T-die coater, a lip coater, a knife coater, a curtain coater, an inkjet printer, a bar coater, a roll coater, a spray coater, a comma coater, a reverse roll coater, a direct gravure coater, a reverse gravure coater, an offset gravure coater, a roll kiss coater, a reverse kiss coater, a kiss gravure coater, a reverse kiss gravure coater, an air doctor coater, a wire bar coater, a dip coater, a blade coater, a brush coater, a die slot coater, an offset printing machine, a screen printing machine, etc., or a combination of two or more of these coating methods can be used. When printing, the ink is diluted with a diluting solvent, for example, a mixture of an acetate ester-based organic solvent such as ethyl acetate or butyl acetate with an alcohol-based organic solvent such as ethyl alcohol, isopropyl alcohol or normal propyl alcohol, to a viscosity and concentration suitable for various printing methods such as gravure printing or flexographic printing, and then supplied to each printing unit either alone or in a mixture.

[0116] [Laminate] The laminate of the present invention has at least a first base film, a gas barrier coating layer (A), an ink layer (B), and a second base film. The laminate of the present invention preferably has the first base film, the gas barrier coating layer (A), the ink layer (B), and the second base film laminated in this order, or the first base film, the ink layer (B), the gas barrier coating layer (A), and the second base film laminated in this order. An adhesive layer, a primer layer, an anchor coating layer, etc. may be provided between each layer, and this is preferred.

[0117] (First base film) Examples of the first substrate film (hereinafter also simply referred to as "substrate") include an OPP film (a polypropylene film, for example, a biaxially oriented polypropylene film), a PET film (a polyethylene terephthalate film, for example, a biaxially oriented polyethylene terephthalate film), a nylon film, and a PE film (uniaxial (MDOPE) or biaxially oriented (BOPE)). The first substrate film may be coated to improve gas barrier properties or ink receptivity when an ink layer is provided. Examples of commercially available coated first substrate films include a K-OPP film and a K-PET film.

[0118] (Second base film) The second substrate film can be made of the same material as the first substrate film, and may include a melt-extruded resin layer or a sealant film. Here, the term "melt-extruded resin layer" refers to a resin layer formed by laminating a molten resin onto the surface of an ink layer or the like in an extrusion lamination configuration. This melt-extruded resin layer is preferably an olefin-based resin such as polyethylene or polypropylene. By using an extrusion-molten layer as the second substrate film, it can adhere more firmly to the ink layer surface, which is roughened by the inclusion of silica.

[0119] From the viewpoint of improving recyclability, the laminate of the present invention preferably has a mono-material structure, and it is particularly preferable to use a polyolefin resin (polyethylene, polypropylene). That is, both the first base film and the second base film are preferably polyolefin resins, and more preferably both the first base film and the second base film are polyethylene-based resins or both the first base film and the second base film are polypropylene-based resins. From the viewpoint of providing recyclability, the olefin ratio in the laminate is preferably 80% or more, more preferably 90% or more, and even more preferably 90% or more. Examples of the sealant film include a CPP film (unstretched polypropylene film) and an LLDPE film (linear low-density polyethylene resin film).

[0120] It is also preferable to use a film formed from a material containing a biomass-derived component as the first base film or the second base film. Biomass films are commercially available from various companies, and for example, sheets such as those listed in the list of biomass-certified products listed by the Japan Organics Recycling Association can be used.

[0121] Specifically, well-known films are made from biomass-derived ethylene glycol. Biomass-derived ethylene glycol is made from ethanol (biomass ethanol) produced from biomass as a raw material. For example, biomass-derived ethylene glycol can be obtained by converting biomass ethanol into ethylene oxide by a conventionally known method to produce ethylene glycol. Alternatively, commercially available biomass ethylene glycol may be used; for example, biomass ethylene glycol commercially available from India Glycoal Limited can be suitably used.

[0122] Alternatively, products made from biomass materials classified by the biomass plastic content specified by ISO 16620 or ASTM D6866 are also available. Radioactive carbon-14C exists in the atmosphere at a ratio of 1 in 1012 particles, and this ratio is the same for atmospheric carbon dioxide, so this ratio remains the same even in plants that fix this carbon dioxide through photosynthesis. Therefore, the carbon in plant-derived resins contains radioactive carbon-14C. In contrast, the carbon in fossil fuel-derived resins contains almost no radioactive carbon-14C. Therefore, by measuring the concentration of radioactive carbon-14C in the resin using an accelerator mass spectrometer, the plant-derived resin content, i.e., the biomass plastic content, can be determined. Examples of plant-derived low-density polyethylene that is a biomass plastic having a biomass plastic content of 80% or more, preferably 90% or more as specified by ISO 16620 or ASTM D6866 include products manufactured by Braskem under the trade names "SBC818," "SPB608," "SBF0323HC," "STN7006," "SEB853," and "SPB681," and films using these as raw materials can be suitably used.

[0123] For example, as an alternative to conventional polyethylene terephthalate films made from petroleum-based raw materials, films containing biomass polyesters and biomass polyethylene terephthalates, which have biomass-derived ethylene glycol as the diol unit and fossil fuel-derived dicarboxylic acids as the dicarboxylic acid units, are known. The dicarboxylic acid units of the biomass polyester are derived from fossil fuels, and aromatic dicarboxylic acids, aliphatic dicarboxylic acids, and derivatives thereof can be used without limitation.

[0124] Furthermore, the copolymer polyester may be one in which, in addition to the above diol component and dicarboxylic acid component, a copolymerization component is added as a third component, such as a bifunctional oxycarboxylic acid, or at least one polyfunctional compound selected from the group consisting of a trifunctional or higher functional polyhydric alcohol, a trifunctional or higher functional polycarboxylic acid and / or anhydride thereof, and a trifunctional or higher functional oxycarboxylic acid, in order to form a crosslinked structure.

[0125] Furthermore, for example, as an alternative to conventional polyolefin films using petroleum-based raw materials, biomass polyolefin films such as biomass polyethylene films and biomass polyethylene-polypropylene films containing polyethylene resins made from biomass-derived ethylene glycol are also known.

[0126] The polyethylene resin is not particularly limited except that ethylene glycol derived from biomass is used as part of the raw material, and examples thereof include ethylene homopolymers and copolymers of ethylene and α-olefins with ethylene as the main component (ethylene-α-olefin copolymers containing 90% by mass or more of ethylene units), and these can be used alone or in combination of two or more.

[0127] The α-olefin constituting the copolymer of ethylene and α-olefin is not particularly limited, and examples thereof include α-olefins having 4 to 8 carbon atoms, such as 1-butene, 4-methyl-1-pentene, 1-hexene, and 1-octene. Known polyethylene resins, such as low-density polyethylene resin, medium-density polyethylene resin, and linear low-density polyethylene resin, can be used.

[0128] Among them, linear low-density polyethylene resin (LLDPE) (a copolymer of ethylene and 1-hexene or a copolymer of ethylene and 1-octene) is preferred from the viewpoint of making it more difficult for damage such as holes or tears to occur even when films are rubbed against each other, and has a density of 0.910 to 0.925 g / cm 3 More preferred is a linear low density polyethylene resin in which

[0129] Films and sheets containing starch, a biomass material, or polylactic acid are also known. These can be selected and used appropriately depending on the application.

[0130] The biomass film may be a laminate of multiple biomass films, or may be a laminate of a conventional petroleum-based film and a biomass film.

[0131] These petroleum-based films and biomass films may be laminated with a vapor-deposited layer of a metal such as aluminum or a metal oxide such as silica or alumina, may use a metal foil, or may be used in combination with a barrier film containing a gas barrier layer such as polyvinyl alcohol, an ethylene-vinyl alcohol copolymer, or vinylidene chloride, or may be coated with polyvinyl alcohol, etc. Use of such films can result in a laminate with higher barrier properties against water vapor, oxygen, alcohol, inert gases, volatile organic compounds (fragrances), etc.

[0132] These films may be unstretched or may have been stretched, and the manufacturing method is not limited. A typical stretching method involves melt-extruding a resin into a sheet using an extrusion film-forming method or the like, followed by simultaneous biaxial stretching or sequential biaxial stretching. In the case of sequential biaxial stretching, it is common to first perform longitudinal stretching and then transverse stretching. Specifically, a method is often used that combines longitudinal stretching utilizing the speed difference between rolls with transverse stretching using a tenter.

[0133] The thickness of the substrate film is not particularly limited, but is usually in the range of 1 to 500 μm. The film surface may be subjected to various surface treatments such as flame treatment and corona discharge treatment as necessary to form an adhesive layer without defects such as film breakage or repellency.

[0134] (Other layers) In addition to the above-described configuration, the laminate of the present invention may have any other layer depending on the purpose. Examples of other layers that can be used include, but are not limited to, a metal-vapor-deposited unstretched film, a metal-vapor-deposited stretched film, a transparent metal-vapor-deposited stretched film, a primer layer, an anchor coat layer, and the like. The metal-vapor-deposited unstretched film may be a VM-CPP film obtained by vapor-depositing a metal such as aluminum onto a CPP film. As the metal-deposited stretched film, a VM-OPP film obtained by depositing a metal such as aluminum on an OPP film can be used. Examples of the transparent vapor-deposited stretched film include films obtained by depositing silica or alumina on OPP film, PET film, nylon film, etc. For the purpose of protecting the inorganic vapor-deposited layer of silica or alumina, a film having a coating applied to the vapor-deposited layer may also be used. The metal layer may be an aluminum foil or the like.

[0135] (Adhesive layer) (glue) The adhesive for forming the adhesive layer may be any adhesive that can be used in a general-purpose lamination method, such as dry lamination or wet lamination using a solvent-based lamination adhesive, non-solvent lamination using a solvent-free lamination adhesive, or extrusion lamination using an extruded resin.

[0136] Examples of the solvent-based or solventless laminating adhesive that can be used include one-component or two-component curable or non-curable vinyl resins, (meth)acrylic resins, polyamide resins, polyester resins, polyether resins, polyurethane resins, epoxy resins, rubber resins, etc. The solvent used in the solvent-based laminating adhesive is not particularly limited, and examples that can be used include (organic) solvent-based adhesives diluted with organic solvents, aqueous adhesives diluted with aqueous solvents, and emulsion adhesives. From the viewpoint of curing speed and adhesive strength, a solvent-based or solventless two-component curing adhesive, which is a two-component curing polyurethane resin adhesive made of a polyol and an isocyanate compound, is often used.

[0137] Pressure-sensitive adhesives can also be used, and pressure-sensitive adhesives are preferred. Examples of pressure-sensitive adhesives include rubber-based adhesives prepared by dissolving polyisobutylene rubber, butyl rubber, or mixtures thereof in organic solvents such as benzene, toluene, xylene, and hexane, or those prepared by blending these rubber-based adhesives with tackifiers such as abiethoxylated rosin esters, terpene-phenol copolymers, and terpene-indene copolymers, and acrylic-based adhesives prepared by dissolving acrylic copolymers having a glass transition temperature of −20° C. or lower, such as 2-ethylhexyl acrylate-n-butyl acrylate copolymers and 2-ethylhexyl acrylate-ethyl acrylate-methyl methacrylate copolymers, in organic solvents.

[0138] The adhesive may be a functional adhesive. For example, an adhesive having gas barrier properties may be the PASLIM series of oxygen barrier adhesives manufactured by DIC Corporation, which are two-component reactive adhesives of polyester polyol and isocyanate compound. The gas barrier adhesive becomes a gas barrier adhesive layer after curing or drying. The use of a gas barrier adhesive is preferred because it can further enhance the gas barrier properties of the laminate of the present invention.

[0139] The thickness of the adhesive layer is not particularly limited, but in the case of a laminating adhesive, the thickness after curing or drying is generally in the range of 0.1 to 10 μm, preferably 1 to 7 μm and more preferably 2 to 5 μm, and in the case of an extruded resin, for example, the thickness is generally in the range of 0.1 to 50 μm, preferably 1 to 30 μm.

[0140] (Primer layer) The primer layer (hereinafter also referred to as "detachable primer layer") is a layer that is provided as a layer in contact with the substrate, ink layer, or anchor coat layer, making it easier to peel off the ink layer or separate the laminate film into single-layer films. Providing a primer layer on a laminate is preferable because it can improve the recyclability of the laminate and also improve the quality of the recycled plastic. The detachable primer layer is preferably provided either between the first substrate film and the ink layer (B) or between the ink layer (B) and the second substrate film, but can also be provided on both. The detachable primer layer preferably has solubility in an alkaline solution. In this case, any known material can be used for the primer layer, and there are no particular limitations on the material, as long as it is a layer that can be detached from the substrate by dissolving or swelling in an alkaline solution. However, since the primer layer is easily dissolved or hydrolyzed in an alkaline solution, it preferably contains a compound having an acidic group, a water-soluble resin, or an inorganic material that becomes soluble when treated with an alkaline solution.

[0141] <Compounds with an acidic group> The compound having an acidic group may be a resin having an acidic group or a low molecular weight compound having an acidic group. Examples of resins having an acidic group include resins having an acid value such as urethane resins, cellulose-based resins, ketone resins, polyester resins, rosin-modified maleic acid resins, rosin-modified fumaric acid resins, chlorinated polypropylene resins, ethylene-vinyl acetate copolymer resins, vinyl acetate resins, alkyd resins, polyvinyl chloride resins, cyclized rubber, chlorinated rubber, butyral resins, and petroleum resins, as well as radical copolymer resins such as styrene-(meth)acrylic resins, styrene-maleic (anhydride) resins, and terpene-maleic (anhydride) resins, which are copolymerized with polymerizable monomers having an acidic group, such as polymerizable monomers having a carboxyl group such as itaconic acid, maleic acid, fumaric acid, cinnamic acid, or acid anhydrides thereof, polymerizable monomers having a sulfonic acid group such as sulfonated styrene, and polymerizable monomers having a sulfonamide group such as vinylbenzenesulfonamide, and acid-modified polyolefin resins, and these may be used singly or in combination. The resin having an acidic group is more preferably a urethane resin having an acidic group, an acrylic resin having an acidic group, a resin having an acid value such as a rosin-modified maleic acid resin or a rosin-modified fumaric acid resin, or a styrene-maleic (anhydride) resin.

[0142] The acid value of the resin having an acidic group is not particularly limited, but is preferably 150 mgKOH / g or more, and more preferably 150 mgKOH / g or more and 500 mgKOH / g or less.

[0143] The molecular weight of the resin having an acidic group is not particularly limited, but it is preferable that the weight average molecular weight (Mw) is in the range of 500 or more and 20,000 or less.

[0144] The low molecular weight compound having an acidic group can be, for example, an organic acid. Preferred examples of the low molecular weight compound having an acidic group include saturated fatty acids, unsaturated fatty acids, hydroxy acids, aromatic carboxylic acids, dicarboxylic acids, tricarboxylic acids, oxocarboxylic acids, and carboxylic acid derivatives, and these can be used singly or in combination.

[0145] The acid value of the compound having an acidic group is not particularly limited, but is preferably 1 mgKOH / g or more, more preferably 3 mgKOH / g or more, more preferably 5 mgKOH / g or more, more preferably 10 mgKOH / g or more, more preferably 20 mgKOH / g or more, more preferably 30 mgKOH / g or more, more preferably 40 mgKOH / g or more, and more preferably 50 mgKOH / g or more. The acid value is preferably 900 mgKOH / g or less, more preferably 850 mgKOH / g or less, more preferably 800 mgKOH / g or less, more preferably 750 mgKOH / g or less, more preferably 700 mgKOH / g or less, more preferably 650 mgKOH / g or less, more preferably 600 mgKOH / g or less, and more preferably 550 mgKOH / g or less. By setting the acid value within the above range, both alkaline solution releasability and adhesion to the substrate can be achieved.

[0146] <Water-soluble resin> The water-soluble resin may be any resin that swells or dissolves in water and can be released from the plastic substrate. Such resins can be selected from known resins as long as they do not impair water solubility. Examples include water-soluble polyester resins, water-soluble polyamide resins, water-soluble polyimide resins, water-soluble acrylic resins, water-soluble polyurethane resins, water-soluble polyallylamine resins, water-soluble phenolic resins, water-soluble epoxy resins, water-soluble phenoxy resins, water-soluble urea resins, water-soluble melamine resins, polyvinyl alcohol resins, and modified versions of these resins. These resins can be used alone or in combination. Among these, polyvinyl alcohol (PVA) resins are preferred from the viewpoints of availability and release properties. The polyvinyl alcohol-containing primer layer is preferably a resin layer containing at least 25% by mass of polyvinyl alcohol.

[0147] <Inorganic materials that become soluble when treated with alkaline solutions> Examples of inorganic materials that dissolve when treated with an alkaline solution include inorganic oxides such as alumina, silica, zirconia, magnesia, ceria, yttria, zinc oxide, and iron oxide; inorganic nitrides such as silicon nitride, titanium nitride, and boron nitride; ceramics such as silicon carbide, calcium carbonate, magnesium sulfate, aluminum sulfate, aluminum hydroxide, aluminum oxide hydroxide, potassium titanate, talc, kaolinite, dickite, nacrite, halloysite, pyrophyllite, montmorillonite, sericite, mica, amesite, bentonite, asbestos, zeolite, calcium silicate, magnesium silicate, diatomaceous earth, and silica sand; metals such as aluminum; and glass fibers. These inorganic materials may be used alone or in combination. These inorganic materials are soluble in alkaline solutions, which contribute to the release of the primer layer.

[0148] The form containing these inorganic materials may be a layer containing particles containing the inorganic material and a binder resin, or may be a vapor-deposited layer of at least one type selected from the group consisting of the inorganic materials. When a layer containing a binder resin is used, the binder resin is not particularly limited, but examples thereof include cellulose-based resins, urethane resins, polyamide resins, vinyl chloride-vinyl acetate copolymer resins, ketone resins, polyester resins, (meth)acrylic resins, rosin-modified maleic acid resins, rosin-modified fumaric acid resins, chlorinated polypropylene resins, ethylene-vinyl acetate copolymer resins, vinyl acetate resins, alkyd resins, polyvinyl chloride resins, cyclized rubbers, chlorinated rubbers, butyral resins, and petroleum resins, and these can be used in appropriate combinations. Among these, urethane resins, (meth)acrylic resins, rosin-based resins, and modified products thereof are often used in appropriate combinations. Furthermore, the mass ratio of the binder resin to the metal particles (binder resin / metal particles) is preferably 90 / 10 to 20 / 80. In the case of a vapor deposition layer, it is preferably made of at least one material selected from alumina, silica, and aluminum, and can be formed by a conventionally known method, with no particular limitations on its composition or formation method.

[0149] The primer layer is obtained by applying a primer layer-forming composition containing the above-mentioned resin, as well as solvents such as organic solvents and aqueous solvents, and auxiliary agents, to a substrate and drying the composition. Depending on the configuration of the laminate, the primer layer may be provided on an ink layer or an adhesive layer. The primer layer is applied in an amount of approximately 0.1 to 5 μm (dry thickness); however, a thickness of less than 0.1 μm makes it difficult to apply uniformly, and a thickness of more than 5 μm is uneconomical and therefore impractical. Conventional application methods, such as gravure, letterpress, flexography, roll coater, reverse coater, and spraying, are used for application. The formation of the primer layer and printing thereon can be performed continuously (in-line), or the formation of the primer layer and printing can be performed separately.

[0150] (Anchor coat layer) The anchor coat layer can be made of a known adhesive or anchor coat agent for film lamination, such as, but not limited to, an anchor coat agent containing one or more resins selected from the group consisting of polybutadiene resins and polyisocyanate resins. When laminating by extrusion lamination, a known anchor coating agent for extrusion lamination can be used as an adhesive aid. When a material having gas barrier properties is used in combination with these adhesives or anchor coating agents, a laminate with particularly excellent barrier properties can be obtained. As an adhesive with excellent gas barrier properties, 3 g / m 2 The oxygen barrier property of the cured coating of adhesive applied with (non-volatile components) is 300cc / m 2 / day / atm or less, or water vapor barrier property of 120g / m 2 / day. Commercially available products include the "PASLIM" series, such as PASLIM VM001 and PASLIM J350X, manufactured by DIC Corporation, and "Maxieve" manufactured by Mitsubishi Gas Chemical Company, Inc. In the laminate of the present invention, it is preferable that an anchor coat layer is present between the ink layer (B) and the second base film, or between the gas barrier coat layer (A) and the second base film, and it is preferable that the anchor coat layer is made of one or more resins selected from the group consisting of polyethyleneimine-based resins, polybutadiene-based resins, and polyisocyanate-based resins.

[0151] Preferred embodiments of the laminate of the present invention include, but are not limited to, the following.

[0152] (1) First base film / gas barrier coating layer (A) / ink layer (B) / adhesive layer / sealant film (2) First base film / ink layer (B) / gas barrier coating layer (A) / adhesive layer / sealant film (3) First base film / gas barrier coating layer (A) / ink layer (B) / anchor coating layer / melt-extruded resin layer (4) First base film / ink layer (B) / gas barrier coating layer (A) / anchor coating layer / melt-extruded resin layer (5) First base film / gas barrier coating layer (A) / ink layer (B) / anchor coating layer / melt-extruded resin layer / sealant film (6) First base film / ink layer (B) / gas barrier coating layer (A) / anchor coating layer / melt-extruded resin layer / sealant film (7) First base film / gas barrier coating layer (A) / ink layer (B) / removable primer layer / adhesive layer / sealant film (8) First base film / removable primer layer / ink layer (B) / gas barrier coating layer (A) / adhesive layer / sealant film (9) First base film / gas barrier coating layer (A) / ink layer (B) / detachable primer layer / anchor coating layer / melt-extruded resin layer (10) First base film / detachable primer layer / ink layer (B) / gas barrier coating layer (A) / anchor coating layer / melt-extruded resin layer (11) First base film / gas barrier coating layer (A) / ink layer (B) / detachable primer layer / anchor coating layer / melt-extruded resin layer / sealant film (12) First base film / gas barrier coating layer (A) / ink layer (B) / anchor coating layer / detachable primer layer / melt-extruded resin layer / sealant film (13) First base film / detachable primer layer / ink layer (B) / gas barrier coating layer (A) / anchor coating layer / melt-extruded resin layer / sealant film (14) First base film / detachable primer layer / gas barrier coating layer (A) / ink layer (B) / detachable primer layer / adhesive layer / sealant film (15) First base film / detachable primer layer / ink layer (B) / gas barrier coating layer (A) / detachable primer layer / adhesive layer / sealant film (16) First base film / detachable primer layer / gas barrier coating layer (A) / ink layer (B) / detachable primer layer / anchor coating layer / melt-extruded resin layer (17) First base film / detachable primer layer / ink layer (B) / gas barrier coating layer (A) / detachable primer layer / anchor coating layer / melt-extruded resin layer (18) First base film / detachable primer layer / gas barrier coating layer (A) / ink layer (B) / anchor coating layer / detachable primer layer / melt-extruded resin layer (19) First base film / detachable primer layer / gas barrier coating layer (A) / ink layer (B) / detachable primer layer / anchor coating layer / melt-extruded resin layer / sealant film (20) First base film / detachable primer layer / gas barrier coating layer (A) / ink layer (B) / anchor coating layer / detachable primer layer / melt-extruded resin layer / sealant film (21) First base film / detachable primer layer / ink layer (B) / gas barrier coating layer (A) / detachable primer layer / anchor coating layer / melt-extruded resin layer / sealant film (22) First base film / detachable primer layer / ink layer (B) / gas barrier coating layer (A) / anchor coating layer / melt-extruded resin layer / detachable primer layer / sealant film (23) First base film / detachable primer layer / gas barrier coating layer (A) / ink layer (B) / detachable primer layer / adhesive layer / detachable primer layer / sealant film (24) First base film / detachable primer layer / ink layer (B) / gas barrier coating layer (A) / detachable primer layer / adhesive layer / detachable primer layer / sealant film (25) First base film / detachable primer layer / gas barrier coating layer (A) / ink layer (B) / detachable primer layer / anchor coating layer / detachable primer layer / sealant film

[0153] In producing the laminates of each of the above embodiments, when a gas barrier coating layer (A), a detachable primer layer, etc. is formed on a first base film, the gas barrier coating layer (A), the detachable primer layer, etc. may be formed by an in-line coating method in which a solvent-based barrier coating agent (SB) or an aqueous barrier coating agent (WB) is applied during the film stretching process, and then a stretching process or the like is carried out, or by an off-line coating method in which a solvent-based barrier coating agent (SB) or an aqueous barrier coating agent (WB) is applied after the film stretching process and dried to form the gas barrier coating layer (A), the detachable primer layer, etc.

[0154] <Applications of laminates> The laminate of the present invention can be suitably used for packaging materials or electronic equipment, as electronic equipment, building materials, textiles and leather, home appliances, vehicles such as cars and airplanes, furniture, office supplies, play equipment, sporting goods, or molded parts thereof. Therefore, the laminate of the present invention can be applied to various molded products such as electronic equipment, building materials, textiles and leather, home appliances, vehicles such as cars and airplanes, furniture, office supplies, play equipment, sporting goods, and molded parts for these products. The laminate of the present invention can also be applied to packaging materials (more specifically, multi-layer packaging materials). In addition, it can also be used as a multi-layer packaging material. When used as a multi-layer packaging material, the layer structure can be changed depending on the contents, the environment of use, and the form of use. When used as a packaging material, for example, the contents are filled through the opening, and then the opening is heat-sealed to produce a product using the packaging material formed from the laminate of the present invention. The use of the packaging material is not particularly limited, but it can be used as a packaging material for, for example, food, medicine, sanitary products, cosmetics, electronic equipment, building materials, industrial materials, etc., and is particularly suitable for use in electronic equipment.

[0155] [Recycled materials] As described above, the laminate of the present invention and packaging materials comprising the laminate can be processed as they are using various known recycling plastic processing methods and used as recycled materials. A recycled material can be obtained by a production method including the steps of crushing the laminate of the present invention or packaging material, melt-kneading the crushed film pieces, and pelletizing the melt-kneaded mixture. The binder resin used in the laminate of the present invention has a low chlorine content, and is therefore advantageous in that it does not generate chlorine-based gases even when heated and reprocessed, thereby reducing the risk of equipment deterioration.

[0156] [Manufacturing method for recycled substrates] Furthermore, the substrate film (i.e., recycled substrate) can be obtained again by removing the detachable primer layer from the laminate according to the present invention. An example of a method for removing the detachable primer layer from the laminate using an alkaline solution will be described below.

[0157] The primer layer can be removed from the substrate by, for example, immersion in a warm alkaline solution. There are no particular restrictions on the alkaline substance used in the alkaline aqueous solution used to remove the primer layer, and examples include sodium hydroxide (NaOH), potassium hydroxide (KOH), calcium hydroxide (Ca(OH)2), and ammonia. Preferably, NaOH or KOH is used. In the method for producing an alkaline aqueous solution, NaOH, KOH, ammonia, or the like is uniformly dissolved or dispersed in water, and the concentration or pH is appropriately adjusted to a specified level.

[0158] In the case of a laminate including the primer layer, the primer layer is sandwiched between plastic films, and it takes a considerable amount of time for the alkaline aqueous solution to reach the primer layer, but it is preferable that delamination proceeds in a short time. The immersion time is preferably within 24 hours, more preferably within 12 hours, and even more preferably within 6 hours.

[0159] In this way, the primer layer can be removed by immersing the laminate in a warm alkaline solution. In other words, the recycled substrate can be produced by treating the laminate with an alkaline solution to dissolve the removable primer layer and thereby removing the ink layer from the laminate. That is, the laminate is treated with a warm alkaline solution to remove the ink layer together with the primer layer from the first base film, thereby obtaining a recycled first base film. The same applies even if the laminate has a laminate-type structure, and according to the present invention, the laminate can be treated with a warm alkaline solution to remove the ink layer and / or the second base film together with the primer layer from the first base film, thereby obtaining a recycled first base film, or a recycled first base film and a recycled second base film or sealant film.

[0160] [Manufacturing method for recycled plastic pellets] Furthermore, the recycled base material obtained by the above-described method for producing a recycled base material can be molded in a molding machine to produce recycled plastic pellets. The crusher used for crushing (pulverizing) is not particularly limited and any known crusher may be used. The pulverized film pieces are physically blended using methods such as melt mixing, solvent cast blending, latex blending, and polymer complexing. Melt mixing is particularly common. Examples of kneading devices include tumblers, Henschel mixers, rotary mixers, super mixers, ribbon tumblers, and V-blenders. The film pieces are melt-mixed using such kneading devices and then pelletized. A single-screw or multi-screw extruder is typically used for melt mixing and pelletization. The film pieces may be fed directly into the extruder or may be compressed with or without heating before being added. In addition to these extruders, Banbury mixers, rollers, Ko-kneaders, blast mills, and Prabender Bloutographs can also be used, and these can be operated batchwise or continuously. Alternatively, the film pieces may be used as molding resins without melt mixing and then melt-kneaded in the heating barrel of a molding machine. The recycled plastic pellets may be either deinked and delaminated plastic or non-deinked and non-delaminated laminates, but the former have higher purity and are therefore more valuable as recycled materials. Therefore, it is possible to process films using the recycled plastic pellets obtained by the present invention. [Example]

[0161] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples. In the following examples, "%" in the compositions means "% by mass."

[0162] 1. Measurement and evaluation methods The liquid ink compositions obtained by the methods described below were evaluated by the following test methods.

[0163] (amine value) The amine value is the number of milligrams of potassium hydroxide equivalent to the amount of hydrochloric acid required to neutralize the amino groups contained in 1 g of sample, and was measured in accordance with JIS K0070. Specifically, 0.5 to 2 g of sample was precisely weighed out (sample nonvolatile components: Sg). 50 mL of a 60 / 40 (mass ratio) mixed solution of methanol and methyl ethyl ketone was added to dissolve the precisely weighed sample. Bromophenol blue was added to the resulting solution as an indicator, and the resulting solution was titrated with 0.2 mol / L ethanolic hydrochloric acid solution (titer: f). The point at which the color of the solution changed from green to yellow was taken as the endpoint, and the titer (A mL) at this point was used to calculate the amine value according to the following formula. (Formula) Amine value = (A × f × 0.2 × 56.108) / S [mgKOH / g]

[0164] (acid number) The COOH groups contained in 1 g of urethane resin were determined as the number of mg of KOH required when titrated by the potassium hydroxide method.

[0165] (Weight average molecular weight) The weight average molecular weight (Mw) was measured using gel permeation chromatography (GPC).

[0166] (urethane bond concentration) The urethane bond concentration was calculated by the method using the above-mentioned formula (2).

[0167] (urea bond concentration) The urea binding concentration was calculated by the method using the above-mentioned formula (3).

[0168] (Cellophane tape adhesion) The viscosity of the liquid ink composition was adjusted to 16 seconds (25°C) with ethyl acetate using a Zahn cup #3 (manufactured by Rigo Co., Ltd.), and printed onto OPP film P2161 (thickness: 20 μm) manufactured by Toyobo Co., Ltd. using a gravure proofing machine equipped with a gravure plate with a plate depth of 35 μm. Then, a solvent-based coating agent (SB-1) described below was applied at a coating rate of 2.5 g / m using a bar coater. 2 The coating was applied so that the total amount of the diluted solvent was 100% (non-volatile components), and the coating was dried using a dryer set at 70°C to evaporate the dilution solvent, and then cured at 40°C for 3 days. A cellophane tape (12 mm wide, manufactured by Nichiban) was applied to the coating layer surface of this laminate, and the appearance of the ink layer when quickly peeled off was evaluated on a scale of 1 to 5 as follows: [Evaluation criteria] 5: The ink layer did not peel off at all. 4: 80% or more of the ink layer remained on the film. 3: 50% to 80% of the ink layer remained on the film. 2: 30% to 50% of the ink layer remained on the film. 1: Less than 30% of the ink layer remained on the film.

[0169] (2-liquid stability) The liquid ink compositions were collected in glass bottles, and 4% by mass of CVL Hardener No. 10 (isocyanate curing agent: manufactured by DIC Corporation) was added to 100% by mass of the liquid ink composition. After storing at 40°C for 24 hours, the viscosity was measured and the change in viscosity from before storage was evaluated on a 5-point scale from 1 to 5. 5: No viscosity change. Viscosity change is less than 2 seconds. 4: Slight viscosity change. Viscosity change occurs between 2 seconds and 5 seconds. 3: Viscosity change is somewhat large. Viscosity change is 5 seconds or more but less than 10 seconds. 2: Viscosity change is large. Viscosity change occurs in 10 seconds or more but less than 15 seconds. 1: Viscosity change is very large. Viscosity change lasts for 15 seconds or more.

[0170] (blocking resistance) The viscosity of the liquid ink composition was adjusted to 16 seconds (25°C) with ethyl acetate using a Zahn cup #3 (manufactured by Rigo Co., Ltd.), and printed onto OPP film P2161 (thickness: 20 μm) manufactured by Toyobo Co., Ltd. using a gravure proofing machine equipped with a gravure plate with a plate depth of 35 μm. Then, a solvent-based coating agent (SB-1) described below was applied at a coating rate of 2.5 g / m using a bar coater. 2 The coating was applied so that the total amount of the diluted solvent was 100% (non-volatile components), and the coating was dried using a dryer set at 70°C to evaporate the dilution solvent, and then cured at 40°C for 3 days. The film was placed on top of the laminate so that the coating layer surface and the non-printed surface were in contact with each other, and the pressure was 10 kgf / cm 2 After removal, the state of ink transfer to the non-printed surface was evaluated on a scale of 1 to 5. [Evaluation criteria] 5: The amount of ink transferred to the non-printed surface was 0% and no transfer was observed. 4: Metastasis occurs in less than 10% of cases. 3: Metastasis occurs in 10% to less than 20% of cases. 2: Metastasis occurs in 20% to less than 30% of cases. 1: Metastasis occurs at a rate of 30% or more.

[0171] The laminates obtained by the methods described below were evaluated by the following test methods.

[0172] (Oxygen barrier properties) The laminated body after aging was cut into a size of 10 cm x 10 cm, and the oxygen permeability (cc / m) was measured in accordance with JIS-K7126 (constant pressure method) in an atmosphere of 23°C and 0% RH using an OX-TRAN2 / 21 (oxygen permeability measuring device manufactured by Mocon). 2 The humidity (RH) was measured.

[0173] (Extrusion Laminate Strength) After aging, the laminate was cut into 15mm widths and subjected to a 90-degree peel test (measurement of extrusion laminate strength) at a pulling speed of 50mm / min. The evaluation results were expressed in units of N / 15mm, and samples that could not be peeled and measured due to the extrusion laminate strength being too strong were indicated as FC.

[0174] 2. Preparation of Liquid Ink Composition

[0175] (2-1) Polyurethane resin The raw materials used in the synthesis of the polyurethane resin are shown below. IPDI: Isophorone diisocyanate Polyol A: Polyertes polyol (weight average molecular weight Mw: 2000) consisting of adipic acid and neopentyl glycol Polyol B: Polyeltes polyol (weight average molecular weight Mw: 2000) composed of adipic acid / 2-methylpropanediol Polyol C: Polyeltes polyol (weight average molecular weight Mw: 2000) consisting of sebacic acid, neopentyl glycol, and propylene glycol IPDA: Isophoronediamine CHA: Cyclohexylamine Polyurethane resin 1 was synthesized from the above raw materials as follows. A four-neck flask equipped with a stirrer, thermometer, reflux condenser, and nitrogen gas inlet tube was charged with 49.84 g of IPDI, 231.25 g of polyol A, and 0.03 g of the urethane catalyst DICNATE 425, and the mixture was reacted at 85°C for 6 hours under a nitrogen stream to obtain prepolymer A. Prepolymer A was then added to a mixed solution containing 490 g of ethyl acetate, 210 g of IPA, 17.1 g of IPDA, and 1.81 g of CHA, and the mixture was reacted at 40°C for 4 hours under a nitrogen stream to obtain polyurethane resin 1. The composition and physical properties of polyurethane resin 1 are shown in Table 1 below, and the nonvolatile content, amine value, weight average molecular weight (Mw), urethane bond concentration, and urea bond concentration in polyurethane resin 1 are also shown in Table 1.

[0176] Polyurethanes 2 to 6 were prepared in the same manner as above, except that the composition of polyurethane resin 1 was changed as shown in Table 1 below. The compositions and physical properties of polyurethane resins 1 to 6 are shown in Table 1.

[0177] [Table 1]

[0178] (2-2) Preparation of Liquid Ink Compositions (Inks 1 to 15) <Production Example 1> A liquid ink composition (ink-1) was prepared by mixing and kneading 30.0 parts by mass of the obtained polyurethane resin 1, 30.0 parts by mass of titanium oxide (R-780), 0.5 parts by mass of silica (Sylisia350), 34.5 parts by mass of ethyl acetate, and 5.0 parts by mass of isopropyl alcohol.

[0179] <Ink-2~15> Liquid ink compositions according to Inks-2 to 15 were prepared in the same manner as in Production Example 1 using the compositions and composition ratios shown in Table 2 below. The inks 1 to 15 were subjected to the various evaluations described above.

[0180] [Table 2]

[0181] The raw materials in Table 2 are as follows: Polyvinyl butyral solution: S-LEC BL-10 manufactured by Sekisui Chemical Co., Ltd., ethyl acetate / isopropyl alcohol solution, non-volatile components 15% CAP resin: Eastman Chemical Cellulose Acetate Propionate Resin (CAP482-0.5), 20% non-volatile content, dissolved in ethyl acetate and isopropyl alcohol Ketone-aldehyde resin: Evonik Variplus SK ketone-aldehyde condensation resin, non-volatile content 50% Chlorinated polypropylene resin: Super Chlon SC360 manufactured by Nippon Paper Industries Co., Ltd. (chlorination level 31, non-volatile content 60% (ethyl alcohol solvent used)) Titanium dioxide: Titanium dioxide pigment R-780, surface-treated with alumina and silica, manufactured by Ishihara Sangyo Kaisha, Ltd. FASTGEN BLUE LA5380: Phthalocyanine blue pigment manufactured by DIC Corporation Silica: Sylisia 350 manufactured by Fuji Silysia Chemical Ltd.

[0182] From the experimental results in Table 2, inks 1 to 13 using polyurethane resins 1 to 4 with amine values ​​of 0.1 to 10 mgKOH / g had excellent cellophane tape adhesion and good two-component stability. On the other hand, Ink-14, which used polyurethane resin 5 with an amine value of 0 mgKOH / g, had poor cellophane tape adhesion. Ink-15, which used polyurethane resin 6 with an amine value of 11 mgKOH / g, had good cellophane tape adhesion but poor two-component stability.

[0183] 3. Barrier Coating Preparation

[0184] (3-1) Preparation of solvent-based barrier coating agent <Synthesis of polyester polyol (SB-A)> A polyester reactor equipped with a stirrer, nitrogen gas inlet tube, Snyder tube, and condenser was charged with 1.26 parts by mass of ethylene glycol, 26.76 parts by mass of glycerol (glycerin), and 40.99 parts by mass of phthalic anhydride. The temperature was gradually increased so that the upper temperature of the distillation tube did not exceed 100°C, and the internal temperature was maintained at 190°C. When the acid value reached 40 mg KOH / g, 7.33 parts by mass of phthalic anhydride was added, and the esterification reaction was terminated when the acid value reached 70 mg KOH / g. A polyester polyol (SB-A) with a hydroxyl value of 165 mg KOH / g and a number average molecular weight of 900 was obtained.

[0185] <Preparation of Solvent-Based Barrier Coating Agent (SB-1)> A total of 85.3 parts by mass of materials were mixed to prepare solvent-based barrier coating agent SB-1: 17.0 parts by mass of a trimethylolpropane adduct of xylylene diisocyanate, 10.0 parts by mass of polyester polyol (SB-A), 16.0 parts by mass of mica (HM6025 manufactured by HENGHAO (average particle size 8 μm, aspect ratio 100)), 2.30 parts by mass of isosorbide, 20.0 parts by mass of ethyl acetate, and 20.0 parts by mass of methyl ethyl ketone (MEK).

[0186] <Preparation of Solvent-Based Barrier Coating Agent (SB-2)> A total of 85.3 parts by mass of materials were mixed to prepare solvent-based barrier coating agent SB-2: 17.0 parts by mass of a trimethylolpropane adduct of xylylene diisocyanate, 10.0 parts by mass of polyester polyol (SB-A), 16.0 parts by mass of mica (HM6025 manufactured by HENGHAO (average particle size 8 μm, aspect ratio 100)), 2.30 parts by mass of trimethylolpropane, 20.0 parts by mass of ethyl acetate, and 20.0 parts by mass of methyl ethyl ketone (MEK).

[0187] (3-2) Preparation of aqueous barrier coating (WB) <Preparation of aqueous barrier coating agent (WB-1)> A reaction vessel equipped with a stirrer, nitrogen gas inlet, and reflux condenser was charged with PVA60-98 (a fully saponified polyvinyl alcohol resin manufactured by Kuraray Co., Ltd.) and ion-exchanged water. The mixture was gradually heated to 90°C and stirred for 4 hours to dissolve the vinyl alcohol polymer. After cooling to room temperature, an aqueous solution of the vinyl alcohol polymer was obtained. To this solution, an aqueous solution of polyethyleneimine (number-average molecular weight: 70,000, 25% primary amino groups, 50% secondary amino groups, 25% tertiary amino groups), water, and isopropanol were added, with the nonvolatile components of the resin being 5% by weight, the water / IPA ratio being 7 / 3, and the vinyl alcohol polymer / polyethyleneimine ratio being 95 / 5, yielding aqueous barrier coating agent WB-1.

[0188] <Preparation of aqueous barrier coating agent (WB-2)> A reaction vessel equipped with a stirrer, nitrogen gas inlet tube, and reflux condenser was charged with a vinyl alcohol polymer, EXCEVAL AQ-4104 (Kuraray Co., Ltd., fully saponified specially modified polyvinyl alcohol resin), and ion-exchanged water. The mixture was gradually heated to 90°C and stirred for 4 hours to dissolve the vinyl alcohol polymer, and then cooled to room temperature to obtain an aqueous solution of the vinyl alcohol polymer. To this was added an aqueous solution of polyethyleneimine (number average molecular weight: 70,000, primary amino groups: 25%, secondary amino groups: 50%, tertiary amino groups: 25%), water, and isopropanol, such that the non-volatile components of the resin were 5% by mass, the water / IPA ratio was 7 / 3, and the vinyl alcohol polymer / polyethyleneimine ratio was 95 / 5, yielding aqueous barrier coating agent WB-2.

[0189] <Preparation of aqueous barrier coating agent (WB-3)> A reaction vessel equipped with a stirrer, nitrogen gas inlet, and reflux condenser was charged with a vinyl alcohol polymer, Nichigo G-Polymer AZF8035Q (butenediol-vinyl alcohol copolymer, manufactured by Mitsubishi Chemical Corporation), and ion-exchanged water. The mixture was gradually heated to 90°C and stirred for 4 hours to dissolve the vinyl alcohol polymer. After cooling to room temperature, an aqueous solution of polyethylenimine (number-average molecular weight: 70,000, 25% primary amino groups, 50% secondary amino groups, 25% tertiary amino groups), water, and isopropanol were added to the mixture, resulting in a nonvolatile resin content of 5% by weight, a water / IPA ratio of 7 / 3, and a vinyl alcohol polymer / polyethylenimine ratio of 95 / 5, yielding aqueous barrier coating agent WB-3.

[0190] <Preparation of aqueous barrier coating agent (WB-4)> A reaction vessel equipped with a stirrer, nitrogen gas inlet tube, and reflux condenser was charged with PVA60-98 (a fully saponified polyvinyl alcohol resin manufactured by Kuraray Co., Ltd.), a vinyl alcohol polymer, and ion-exchanged water. The mixture was gradually heated to 90°C and stirred for 4 hours to dissolve the vinyl alcohol polymer, after which it was cooled to room temperature to obtain an aqueous solution of the vinyl alcohol polymer. Water and isopropanol were added to this solution so that the nonvolatile components of the resin were 5% by mass and the water / IPA ratio was 8 / 2, yielding aqueous barrier coating agent WB-4.

[0191] 4. Manufacturing of laminates (4-1) Lamination of gas barrier coating layer (A) <Application method of solvent-based barrier coating agent (SB)> The coating agent prepared above was applied using a bar coater at a coating amount of 2.5 g / m 2 The coating was applied so that the total amount of the diluted solvent was 100% (non-volatile components), and the coating was dried using a dryer set at 70°C to evaporate the dilution solvent, and then cured at 40°C for 3 days.

[0192] <Water-based barrier coating (WB) application method> The coating agent prepared above was applied using a bar coater at a coating amount of 0.4 g / m 2 (non-volatile components) and dried for 1 minute in a dryer set at a temperature of 80°C.

[0193] (4-2) Lamination of ink layer (B) <Ink application method> The viscosity of the liquid ink composition prepared above was adjusted to 16 seconds (25°C) using a Zahn cup #3 (manufactured by Rigo Co., Ltd.) with ethyl acetate, and the ink was applied using a gravure proofing machine equipped with a gravure plate with a plate depth of 35 μm. The diluted solvent was evaporated and the ink was dried using a dryer set at a temperature of 70°C. The coating amount of the printed layer was 2.2 g / m. 2 It was.

[0194] (4-3) Lamination of melt-extruded resin layers <Method for producing melt-extruded resin layer and method for extrusion laminating sealant film> Polyethyleneimine or isocyanate anchor coating agent at 0.1g / m 2 After coating, molten polyethylene was laminated to a thickness of 40 μm using an extrusion laminator. When a sealant film was included in the laminated structure, the sealant film was laminated with molten polyethylene having a thickness of 40 μm.

[0195] 5. Fabrication of Laminates

[0196] (5-1) Examples 1 to 22 and Comparative Examples 1 to 5 The laminate of Example 1 was obtained by using OPP as the first substrate film, laminating SB-1, a solvent-based barrier coating agent, as the gas barrier coating layer (A), Ink-1 as the ink layer (B), laminating a polyethyleneimine-based anchor coating layer as the anchor coating layer, and laminating polyethylene as the melt-extruded resin layer, which is the second substrate film. Furthermore, laminates of Examples 2 to 22 and Comparative Examples 1 to 5 were obtained in the same manner as in Example 1, except that the laminate structure was changed as shown in Table 3. The layers of the laminate were stacked in order from top to bottom in Table 3, and blank cells indicate that no layers were stacked.

[0197] (5-2) Examples 23 to 47 and Comparative Example 6 Laminates of Examples 23 to 47 and Comparative Example 6 were obtained in the same manner as in Example 1, except that the layer structure was changed as shown in Table 4. The layers of the laminate were stacked in order from the top in Table 4, and blank cells indicate that no layers were stacked.

[0198] [Table 3]

[0199] [Table 4]

[0200] The materials used in Tables 3 and 4 are as follows: (First base film) OPP: Toyobo OPP film P2161 (thickness: 20 μm) MDOPE: MDOPE film PE3K-H (thickness: 25 μm) manufactured by Futamura Chemical Co., Ltd. (Anchor coat layer) Imine: Polyethyleneimine anchor coating agent, DIC Dry AC-108 manufactured by DIC Corporation Isocyanate: Isocyanate anchor coating agent, Dick Dry, manufactured by DIC Corporation, LX-500 / KR-90S (melt-extruded resin layer) PE: Polyethylene (sealant film) CPP: Toyobo CPP film P1128 (thickness 30 μm) LLDPE: Polyethylene film TUX-HC (thickness 40 μm) manufactured by RM Tocello Co., Ltd.

[0201] The results in Tables 3 and 4 show that the laminates of the present invention exhibited good oxygen barrier properties and extrusion laminate strength regardless of the lamination order of the barrier coat layer (A) and the ink layer (B). On the other hand, Comparative Examples 2 to 4, which did not have a gas barrier coat layer (A), exhibited poor oxygen barrier properties. Furthermore, Comparative Examples 1, 5, and 6, which were laminates using Ink-14, which had an amine value of 0 mgKOH / g, exhibited relatively poor extrusion laminate strength, and the extrusion laminate strength significantly decreased depending on the lamination order of the barrier coat layer (A) and the ink layer (B), imposing limitations on production. [Industrial Applicability]

[0202] According to the present invention, a laminate can be provided that uses a liquid ink resin composition that is excellent in both adhesion and two-component stability, has excellent gas barrier properties and (extrusion) lamination strength, and has no restrictions on the order in which the barrier coat layer and the ink layer are laminated.Furthermore, the present invention can provide a recycled material using the laminate, a method for producing a recycled substrate using the laminate, and a method for producing recycled plastic pellets using the recycled substrate.

[0203] [Contribution to the United Nations-led Sustainable Development Goals (SDGs)] The SDGs have been proposed to realize a sustainable society. One embodiment of the present invention is expected to be a technology that contributes to goals such as "No. 7 - Affordable and Clean Energy" and "No. 12 - Responsible Consumption and Production."

Claims

1. The film has at least a first substrate film, a gas barrier coating layer (A), an ink layer (B), and a second substrate film, the gas barrier coat layer (A) is a dry coating film of a barrier coating agent (SB) containing a polyester polyol obtained by polycondensation of an acid component containing an ortho- or meta-oriented aromatic polycarboxylic acid with a polyhydric alcohol, and an isocyanate compound (SB-B), or a dry coating film of a barrier coating agent (WB) containing a vinyl alcohol polymer having a saponification degree of 90% or more and an aqueous solvent (WB-B), the ink layer (B) contains a polyurethane resin, and the amine value of the non-volatile component of the polyurethane resin is 0.1 mgKOH / g to 10 mgKOH / g; the second substrate film includes a melt-extruded resin layer, an anchor coat layer is provided between the ink layer (B) and the second base film or between the gas barrier coat layer (A) and the second base film; the anchor coat layer is made of one or more resins selected from the group consisting of polyethyleneimine-based resins, polybutadiene-based resins, and polyisocyanate-based resins; Laminate.

2. The laminate of claim 1 , wherein the barrier coating (WB) further comprises a polyalkyleneimine.

3. The ink layer (B) further contains one or more resins selected from the group consisting of cellulose-based resins, vinyl chloride-vinyl acetate resins, polyester resins, acrylic resins, polyamide resins, rosin-modified maleic acid resins, polyvinyl butyral resins, chlorinated polyolefin resins, and ketone aldehyde resins. The laminate according to claim 1 .

4. the chlorine content in the resin component contained in the ink layer (B) is 5% by mass or less; The laminate according to claim 1 .

5. The first base film, the gas barrier coating layer (A), the ink layer (B), and the second base film are laminated in this order, or the first base film, the ink layer (B), the gas barrier coating layer (A), and the second base film are laminated in this order. The laminate according to claim 1 .

6. The first base film and the second base film are both made of a polyolefin resin. The laminate according to claim 1 .

7. a removable primer layer is provided either between the first base film and the ink layer (B) or between the ink layer (B) and the second base film; The laminate according to claim 1 .

8. The removal primer layer has solubility in an alkaline solution. The laminate according to claim 7.

9. A recycled material using the laminate according to claim 7.

10. A method for producing a recycled substrate, comprising the steps of: treating the laminate according to claim 7 with an alkaline solution to dissolve the detachable primer layer, thereby removing the ink layer from the laminate.

11. A method for producing recycled plastic pellets, comprising molding the recycled base material obtained by the method for producing a recycled base material according to claim 10 using a molding machine.

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