Two-component curable adhesive, laminate, laminate for blister pack, and blister pack

Abstract

Provided are: a packaging material which has excellent moldability, does not cause a decrease in interlayer adhesive strength even after thermal bonding between sealant layers for sealing the contents, and has no visual defects such as delamination; a two-component adhesive which is suitable for manufacturing such a packaging material and has excellent moldability and thermal resistance; a laminate using the two-component adhesive; a laminate for a blister pack; and a blister pack.　A two-component adhesive comprising a polyol composition (X) and a polyisocyanate composition (Y), wherein the polyol composition (X) contains a polyester polyol (A) and a urethane resin (B) having a melting point of 0-60°C, and the polyisocyanate composition (Y) contains a polyisocyanate compound (D). A laminate and a packaging material obtained using said adhesive.

Description

Two-component curing adhesives, laminates, laminates for blister packs, blister packs

[0001] The present invention relates to a two-component curing adhesive, a laminate, a laminate for blister packs, and a blister pack.

[0002] Packaging materials used to package a variety of items, including food, daily necessities, and electronic devices, require properties such as strength, crack resistance, and gas barrier properties to protect the contents from impacts during distribution and from deterioration due to oxygen and moisture. When heat sterilization is performed on the contents, retort resistance and heat resistance are necessary, and transparency is sometimes required to allow the contents to be viewed. However, it is difficult to satisfy all the required functions with a single material. For example, unstretched polyolefin films used for heat-sealing have excellent thermal processability, but insufficient oxygen barrier properties. Conversely, nylon films have excellent gas barrier properties but poor heat-sealing properties.

[0003] For these reasons, laminates made by bonding different types of polymer materials or polymer materials and metal substrates are widely used as packaging materials. Furthermore, laminates molded to form one or more storage sections are sometimes used as packaging materials (Patent Documents 1 and 2). A laminate with one or more storage sections formed therein is sealed by joining it to a laminate with a storage section of the same shape formed therein or to a laminate without a storage section formed therein (not molded). Heat fusion (heat sealing) is used as the joining method.

[0004] JP 2013-199283 A JP 2008-535746 A

[0005] An object of the present invention is to provide a packaging material suitable for such applications, i.e., a packaging material that has excellent formability, does not lose adhesive strength between the layers even after heat fusion of the sealant layers to seal the contents, and is free from poor appearance such as lifting between the layers. Another object of the present invention is to provide a two-component adhesive that has excellent formability and heat resistance and is suitable for producing such packaging materials, as well as a laminate, a laminate for blister packs, and a blister pack that use the same.

[0006] That is, the present invention relates to a two-component curing adhesive comprising a polyol composition (X) and a polyisocyanate composition (Y), wherein the polyol composition (X) comprises a polyester polyol (A) and a urethane resin (B) having a melting point of 0°C or higher and 60°C or lower, and the polyisocyanate composition (Y) comprises a polyisocyanate compound (D), as well as a laminate and a packaging material obtained using the adhesive.

[0007] According to the present invention, it is possible to provide a packaging material that has excellent moldability, does not experience a decrease in interlayer adhesive strength even after heat fusion of sealant layers to seal stored items, and does not experience poor appearance such as lifting between layers, as well as an adhesive and a laminate that are suitable for producing the packaging material.

[0008] <Two-component curing adhesive> The two-component curing adhesive of the present invention is a two-component curing adhesive containing a polyol composition (X) and a polyisocyanate composition (Y). The adhesive of the present invention will be described in detail below.

[0009] (Polyol Composition (X)) The polyol composition (X) contains, as essential components, a polyester polyol (A) and a urethane resin (B).

[0010] (Polyester Polyol (A)) The polyester polyol (A) is a reaction product of a composition containing a polybasic acid or a derivative thereof and a polyhydric alcohol. Examples of the polybasic acid or a derivative thereof used in the synthesis of the polyester polyol (A) include aliphatic polycarboxylic acids such as malonic acid, ethylmalonic acid, dimethylmalonic acid, succinic acid, 2,2-dimethylsuccinic acid, succinic anhydride, alkenylsuccinic anhydride, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, fumaric acid, maleic acid, maleic anhydride, itaconic acid, dimer acid, and trimer acid;

[0011] Alkyl esters of aliphatic polycarboxylic acids, such as dimethyl malonate, diethyl malonate, dimethyl succinate, dimethyl glutarate, dimethyl adipate, diethyl pimelate, diethyl sebacate, dimethyl fumarate, diethyl fumarate, dimethyl maleate, and diethyl maleate;

[0012] Alicyclic polycarboxylic acids such as 1,1-cyclopentanedicarboxylic acid, 1,2-cyclopentanedicarboxylic acid, 1,3-cyclopentanedicarboxylic acid, 1,2-cyclohexanedicarboxylic acid, 1,3-cyclohexanedicarboxylic acid, 1,4-cyclohexanedicarboxylic acid, tetrahydrophthalic anhydride, 4-methylhexahydrophthalic anhydride, hexahydrophthalic anhydride, cyclohexane-1,2,4-tricarboxylic acid-1,2-anhydride, himic acid anhydride, and HET acid anhydride;

[0013] Aromatic polycarboxylic acids such as orthophthalic acid, terephthalic acid, isophthalic acid, phthalic anhydride, 1,4-naphthalenedicarboxylic acid, 2,5-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, 2,3-naphthalenedicarboxylic anhydride, naphthalic acid, trimellitic acid, trimellitic anhydride, pyromellitic acid, pyromellitic anhydride, biphenyldicarboxylic acid, 1,2-bis(phenoxy)ethane-p,p'-dicarboxylic acid, benzophenonetetracarboxylic acid, benzophenonetetracarboxylic dianhydride, 5-sodium sulfoisophthalic acid, tetrachlorophthalic anhydride, and tetrabromophthalic anhydride;

[0014] Methyl esters of aromatic polycarboxylic acids such as dimethyl terephthalic acid and dimethyl 2,6-naphthalenedicarboxylate; and the like, which may be used alone or in combination of two or more.

[0015] The polyhydric alcohol used in the synthesis of the polyester polyol (A) may be a diol or a tri- or higher functional polyol, and examples of the diol include aliphatic diols such as ethylene glycol, diethylene glycol, propylene glycol, 1,3-propanediol, 1,2,2-trimethyl-1,3-propanediol, 2,2-dimethyl-3-isopropyl-1,3-propanediol, 1,4-butanediol, 1,3-butanediol, 3-methyl-1,3-butanediol, 1,5-pentanediol, 3-methyl-1,5-pentanediol, neopentyl glycol, 1,6-hexanediol, 1,4-bis(hydroxymethyl)cyclohexane, 2,2,4-trimethyl-1,3-pentanediol, and dimer diol;

[0016] modified polyether diols obtained by ring-opening polymerization of the aliphatic diols with various cyclic ether bond-containing compounds such as ethylene oxide, propylene oxide, tetrahydrofuran, ethyl glycidyl ether, propyl glycidyl ether, butyl glycidyl ether, phenyl glycidyl ether, and allyl glycidyl ether;

[0017] lactone-based polyester polyols obtained by polycondensation reaction of the aliphatic diols with various lactones such as lactanoids and ε-caprolactone;

[0018] bisphenols such as bisphenol A and bisphenol F;

[0019] Examples include alkylene oxide adducts of bisphenols obtained by adding ethylene oxide, propylene oxide, etc. to bisphenols such as bisphenol A and bisphenol F.

[0020] Tri- or higher functional polyols include aliphatic polyols such as trimethylolethane, trimethylolpropane, glycerin, hexanetriol, and pentaerythritol;

[0021] modified polyether polyols obtained by ring-opening polymerization of the aliphatic polyols with various cyclic ether bond-containing compounds such as ethylene oxide, propylene oxide, tetrahydrofuran, ethyl glycidyl ether, propyl glycidyl ether, butyl glycidyl ether, phenyl glycidyl ether, and allyl glycidyl ether;

[0022] Examples include lactone-based polyester polyols obtained by polycondensation reaction of the above-mentioned aliphatic polyols with various lactones such as ε-caprolactone.

[0023] In view of excellent heat resistance, the polybasic acid preferably contains an aromatic polycarboxylic acid or an alkyl ester of an aromatic polycarboxylic acid (hereinafter collectively referred to as an aromatic polycarboxylic acid). Of the polybasic acids, the aromatic polycarboxylic acid preferably accounts for 30% by mass or more, more preferably 40% by mass or more. The entire amount of the polybasic acid may be an aromatic polycarboxylic acid.

[0024] The polyester polyol (A) may be a polyester polyurethane polyol, which is a reaction product of a composition containing the above-mentioned polybasic acid, polyhydric alcohol, and a polyisocyanate compound. Alternatively, it may be a polyester polyurethane polyol obtained by urethane-extending a polyester polyol obtained from the above-mentioned polybasic acid or polyhydric alcohol with a polyisocyanate compound. The polyisocyanate compound used in this case may be the same as those exemplified as the polyisocyanate compound (D) described below, and may be used alone or in combination.

[0025] The hydroxyl value of the solid content of the polyester polyol (A) is preferably 1.0 to 40.0 mgKOH / g, more preferably 1.0 to 30.0 mgKOH / g, and even more preferably 3.0 to 25.0 mgKOH / g, in order to achieve excellent adhesive strength and a crosslinking density suitable for molding.

[0026] The acid value of the solid content of the polyester polyol (A) is not particularly limited, but is preferably 10 mgKOH / g or less, for example. The acid value of the solid content of the polyester polyol (A) may be 0 mgKOH / g. The hydroxyl value and acid value can be measured by the method described in JIS-K0070.

[0027] The number average molecular weight (Mn) of the polyester polyol (A) can be adjusted as appropriate, but is preferably 3,000 to 100,000, and more preferably 3,500 to 50,000. The weight average molecular weight (Mw) of the polyester polyol (A) is preferably 5,000 to 300,000. In this specification, the number average molecular weight (Mn) and weight average molecular weight (Mw) are values ​​measured by gel permeation chromatography (GPC) under the following conditions:

[0028] Measurement equipment: HLC-8320GPC manufactured by Tosoh Corporation Column: TSKgel 4000HXL, TSKgel 3000HXL, TSKgel 2000HXL, TSKgel 1000HXL manufactured by Tosoh Corporation Detector: RI (differential refractometer) Data processing: Multistation GPC-8020model II manufactured by Tosoh Corporation Measurement conditions: Column temperature: 40°C Developing solvent: tetrahydrofuran Flow rate: 0.35 ml / min Standard: monodisperse polystyrene Sample: 100 μl of a tetrahydrofuran solution of 0.2% by mass (equivalent to resin solids) filtered through a microfilter

[0029] (Urethane Resin (B)) The polyol composition (X) contains a crystalline urethane resin (B). The urethane resin (B) can be obtained, for example, by reacting a urethane prepolymer (a) with an active hydrogen group-containing compound (b) in such a manner that the ratio of the moles of isocyanate groups to the moles of active hydrogen groups [active hydrogen groups] / [NCO] is 0.7 to 1.1, more preferably 0.8 to 1.0.

[0030] The urethane prepolymer (a) is obtained by urethane-forming a polyol (a1) and a polyisocyanate (a2) under conditions in which the isocyanate groups are in excess relative to the hydroxyl groups, for example, at a ratio of 1.4 to 6.5. Examples of the polyol (a1) used in the synthesis of the urethane prepolymer (a) include polyether polyols (a1-1), polyester polyols (a1-2), polycarbonate polyols (a1-3), and polylactone polyols (a1-4), and these may be used alone or in combination of two or more.

[0031] The polyether polyol (a1-1) may be one obtained by ring-opening polymerization of a cyclic ether such as alkylene oxide using a compound having two or more active hydrogen atoms as an initiator.

[0032] Examples of the initiator include compounds having two active hydrogen atoms, such as ethylene glycol, diethylene glycol, propylene glycol, trimethylene glycol, 1,3-butanediol, 1,4-butanediol, 1,6-hexanediol, neopentyl glycol, and water; and compounds having three or more active hydrogen atoms, such as glycerin, diglycerin, trimethylolethane, trimethylolpropane, hexanetriol, monoethanolamine, diethanolamine, triethanolamine, ethylenediamine, pentaerythritol, and sugars, and these can be used alone or in combination of two or more.

[0033] Examples of the polyester polyol (a1-2) include polyester polyols obtained by esterifying a low-molecular-weight polyol (for example, a polyol having a molecular weight of 50 or more and 300 or less) with a polycarboxylic acid.

[0034] Examples of low molecular weight polyols include aliphatic polyols (diols or tri- or higher functional polyols) having 2 to 6 carbon atoms, such as ethylene glycol, propylene glycol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 2-methyl-1,3-propanediol, 3-methyl-1,5-pentanediol, diethylene glycol, dipropylene glycol, neopentyl glycol, 1,3-butanediol, trimethylolpropane, and glycerin; alicyclic structure-containing polyols such as 1,4-cyclohexanediol and cyclohexanedimethanol; and aromatic structure-containing polyols such as bisphenol compounds, such as bisphenol A and bisphenol F, and alkylene oxide adducts thereof.

[0035] Examples of polycarboxylic acids include aliphatic polycarboxylic acids such as succinic acid, adipic acid, sebacic acid, and dodecanedicarboxylic acid; aromatic polycarboxylic acids such as terephthalic acid, isophthalic acid, phthalic acid, and naphthalenedicarboxylic acid; and anhydrides or ester-forming derivatives of these aliphatic polycarboxylic acids and aromatic polycarboxylic acids.

[0036] Examples of the polycarbonate polyol (a1-3) include a reaction product of a carbonate ester with a polyol; a reaction product of phosgene with bisphenol A, etc.

[0037] Examples of carbonate esters include methyl carbonate, dimethyl carbonate, ethyl carbonate, diethyl carbonate, cyclocarbonate, diphenyl carbonate, etc. Examples of polyols that can react with carbonate esters include the low-molecular-weight polyols exemplified above, and high-molecular-weight polyols (weight-average molecular weight of 500 to 5,000) such as polyether polyols (polyethylene glycol, polypropylene glycol, etc.) and polyester polyols (polyhexamethylene adipate, etc.).

[0038] As the polylactone polyol (a1-4), there can be used one or more selected from the group consisting of the polyether polyol (a1-1), polyester polyol (a1-2), and polycarbonate polyol (a1-3) exemplified above, and / or a product obtained by reacting (adding) a lactone compound as an initiator with a low-molecular-weight polyol used in the production of the polyester polyol (a1-2).

[0039] Examples of the lactone compound include δ-valerolactone, β-methyl-δ-valerolactone, ε-caprolactone, α-methyl-ε-caprolactone, β-methyl-ε-caprolactone, γ-methyl-ε-caprolactone, β,δ-dimethyl-ε-caprolactone, 3,3,5-trimethyl-ε-caprolactone, enantholactone (7-heptanolide), dodecanolactone (12-dodecanolide), and the like, and these can be used alone or in combination of two or more.

[0040] The addition rate of the lactone compound is preferably 1 mole or more, more preferably 5 moles or more, even more preferably 10 moles or more, and preferably 100 moles or less, more preferably 50 moles or less, even more preferably 30 moles or less, relative to 1 mole of the initiator.

[0041] The functionality of the polyol (a1) is 2 or more, and may be 3 or more, and is preferably 5 or less. The number average molecular weight of the polyol (a1) is preferably 300 or more, more preferably 500 or more, and is preferably 5,000 or less, more preferably 3,000 or less. When one or more types of polyol (a1) are used, the number average molecular weight can be calculated as a weighted average value of the number average molecular weights of the polyols (a1).

[0042] Examples of the polyisocyanate (a2) include aromatic polyisocyanates such as 4,4'-diphenylmethane diisocyanate, 2,4'-diphenylmethane diisocyanate, carbodiimide-modified diphenylmethane diisocyanate, crude diphenylmethane diisocyanate, phenylene diisocyanate, tolylene diisocyanate, and naphthalene diisocyanate; polyisocyanates having an alicyclic structure such as cyclohexane diisocyanate, dicyclohexylmethane diisocyanate, and isophorone diisocyanate; and aliphatic polyisocyanates such as hexamethylene diisocyanate, lysine diisocyanate, xylylene diisocyanate, and tetramethylxylylene diisocyanate, and these may be used alone or in combination of two or more.

[0043] The number average molecular weight of the urethane prepolymer (a) can be adjusted as appropriate, but is, for example, 250 or more, more preferably 500 or more, and preferably 10,000 or less, more preferably 5,000 or less.

[0044] The active hydrogen group-containing compound (b) includes polyol compounds (b1) and polyamine compounds (b2), and these can be used alone or in combination of two or more.

[0045] Examples of the polyol compound (b) include ethylene glycol, diethylene glycol, 1,2-propanediol, 1,3-propanediol, 2-methyl-1,3-propanediol, 2-butyl-2-ethyl-1,3-propanediol, 1,3-butanediol, 1,4-butanediol, neopentyl glycol (2,2-dimethyl-1,3-propanediol), 2-isopropyl-1,4-butanediol, 3-methyl-2,4-pentanediol, 2,4-pentanediol, 1,5-pentanediol, 3-methyl-2,4-pentanediol, 2,4-pentanediol, 1,5-pentanediol, 2 ... aliphatic diols such as 2-ethyl-1,5-pentanediol, 2-methyl-2,4-pentanediol, 2,4-dimethyl-1,5-pentanediol, 2,4-diethyl-1,5-pentanediol, 1,5-hexanediol, 1,6-hexanediol, 2-ethyl-1,3-hexanediol, 2-ethyl-1,6-hexanediol, 1,7-heptanediol, 3,5-heptanediol, 1,8-octanediol, 2-methyl-1,8-octanediol, 1,9-nonanediol, and 1,10-decanediol; aliphatic triols such as glycerin and trimethylolpropane; tetra- or higher functional aliphatic polyols such as pentaerythritol and dipentaerythritol; alicyclic diols such as cyclohexanedimethanol (for example, 1,4-cyclohexanedimethanol), cyclohexanediol (for example, 1,3-cyclohexanediol, 1,4-cyclohexanediol), and 2-bis(4-hydroxycyclohexyl)-propane; bisphenol compounds such as bisphenol A; alkylene oxide adducts of bisphenol compounds; and polymer polyols such as polyether polyols, polyester polyols, polycaprolactone polyols, and polycarbonate polyols.

[0046] Examples of the polyamine compound (b2) include aliphatic or alicyclic amine compounds such as ethylenediamine, propanediamine, hexanediamine, and isophoronediamine; aromatic amine compounds such as phenylenediamine, 3,3'-dichloro-4,4'-diaminodiphenylmethane, and polyaminochlorophenylmethane compounds; polymers (preferably dimers to tetramers) of aromatic amine compounds; and mixtures thereof.

[0047] When the active hydrogen group-containing compound (b) contains the polyamine compound (b2), the content thereof may be, for example, 0.1 parts by mass or more, or even 1 part by mass or more, and is preferably 10 parts by mass or less, and more preferably 5 parts by mass or less, relative to 100 parts by mass of the polyol compound (b1). The active hydrogen group-containing compound (b) does not necessarily contain the polyamine compound (b2).

[0048] In preparing the urethane resin (B), in addition to the urethane prepolymer (a) and the active hydrogen group-containing compound (b), one or more of the following may be used: an organic solvent, a modifier, a catalyst, a foam stabilizer, a curing agent, a filler, a pigment, a thickener, an antioxidant, an ultraviolet absorber, a surfactant, a flame retardant, a plasticizer, and reinforcing fibers (glass (long fiber / short fiber), carbon fiber, etc.).

[0049] The urethane resin (B) used in the adhesive of the present invention has a melting point of 0° C. or higher and 60° C. or lower. By using such a urethane resin (B) in combination, an adhesive excellent in adhesive strength, moldability, and heat resistance can be obtained. The melting point of the urethane resin (B) is more preferably 10° C. or higher and 60° C. or lower, and even more preferably 25° C. or higher and 60° C. or lower.

[0050] The urethane resin (B) used in the adhesive of the present invention preferably has a heat of fusion of 10 mJ / mg or more and 80 mJ / mg or less, and more preferably 30 mJ / mg or more and 80 mJ / mg or less.

[0051] The urethane resin (B) used in the adhesive of the present invention preferably has a glass transition temperature of −10° C. or lower, as this improves moldability. The glass transition temperature of the urethane resin (B) is more preferably −30° C. or lower, and it is acceptable if the glass transition temperature is not observable by the method described below (i.e., the glass transition temperature is considerably low).

[0052] The glass transition temperature, melting point, and heat of fusion of the urethane resin (B) are measured as follows. Using a differential scanning calorimeter (DSC-7000 manufactured by SII Nanotechnology Inc., hereinafter referred to as DSC), 5 mg of a sample is cooled from room temperature to -80°C at 10°C / min under a nitrogen stream of 20 mL / min, then held for 10 minutes, and then heated to 200°C at 10°C / min and held for 10 minutes to remove thermal history. The sample is then cooled to -80°C at 10°C / min, held for 10 minutes, and then heated again to 200°C at 10°C / min to measure the DSC curve. The glass transition point is determined by the intersection of a straight line extending the low-temperature baseline in the measurement results observed in the second cooling step toward the high-temperature side and a tangent drawn at the point where the gradient of the step-like portion of the glass transition curve is maximum, and the temperature at this point is determined as the glass transition temperature. The maximum peak temperature of the endothermic curve observed in the second heating step is taken as the melting point, and the heat of fusion is calculated from the area enclosed by this maximum peak and the baseline.

[0053] From the viewpoint of a balance between heat resistance, adhesive strength, storage stability, etc., the urethane resin (B) used in the adhesive of the present invention preferably has a number average molecular weight of 10,000 to 300,000, more preferably 10,000 to 100,000. The weight average molecular weight is preferably 10,000 to 300,000, more preferably 10,000 to 200,000, and even more preferably 20,000 to 200,000. The molecular weight distribution (weight average molecular weight / number average molecular weight) of the urethane resin (B) is, for example, 1 to 10.

[0054] The amount of urethane resin (B) can be adjusted as appropriate, but as an example, the proportion of urethane resin (B) in the total amount of polyester polyol (A) and urethane resin (B) is preferably 1% by mass or more and 30% by mass or less, more preferably 3% by mass or more and 25% by mass or less, and even more preferably 4% by mass or more and 25% by mass or less.

[0055] (Polyol (C)) The polyol composition (X) may contain a polyol (C) other than the polyester polyol (A). Examples of the polyol (C) include polycarbonate polyol (C1) and polyoxyalkylene-modified polyol (C2). The number average molecular weight of these polyols (C) is, for example, 300 to 50,000. The amount of polyol (C) in the solid content of the polyol composition (X) is preferably 20 mass% or less. The polyol composition (X) does not necessarily contain the polyol (C).

[0056] (Polyisocyanate Composition (Y)) (Polyisocyanate Compound (D)) The polyisocyanate compound (D) is not particularly limited as long as it is a compound having a plurality of isocyanate groups in one molecule. Examples of such polyisocyanate compound (D) include polyisocyanates having an aromatic structure in the molecular structure, such as tolylene diisocyanate, diphenylmethane diisocyanate, polymeric diphenylmethane diisocyanate, 1,5-naphthalene diisocyanate, triphenylmethane triisocyanate, and xylylene diisocyanate, and compounds in which some of the NCO groups of these polyisocyanates have been modified with carbodiimide;

[0057] Polyisocyanates having an alicyclic structure in the molecular structure, such as isophorone diisocyanate, 4,4'-methylenebis(cyclohexyl isocyanate), and 1,3-(isocyanatomethyl)cyclohexane;

[0058] Linear aliphatic polyisocyanates such as 1,6-hexamethylene diisocyanate, 1,5-pentamethylene diisocyanate, lysine diisocyanate, and trimethylhexamethylene diisocyanate, and compounds in which some of the NCO groups of these polyisocyanates have been modified with carbodiimide;

[0059] Examples include isocyanurates of these polyisocyanates; allophanates of these polyisocyanates; biuret forms of these polyisocyanates; adducts of these polyisocyanates modified with trimethylolpropane; and polyurethane polyisocyanates which are reaction products of these polyisocyanates and polyols.

[0060] The polyisocyanate compound (D) may be one of the polyisocyanates described above, or a combination of two or more of them. The polyisocyanate compound (D) is preferably at least one selected from polyisocyanates having an aromatic structure in their molecular structure and their derivatives (compounds in which some of the NCO groups are modified with carbodiimide, isocyanurates, allophanates, biuret compounds, adducts, and polyurethane polyisocyanates of such polyisocyanates). This allows for a blister pack laminate with superior heat resistance. The content of polyisocyanates having an aromatic structure in their molecular structure and their derivatives in the polyisocyanate compound (D) is preferably 50% by mass or more. The entire amount of the polyisocyanate compound (D) may be polyisocyanates having an aromatic structure in their molecular structure and their derivatives.

[0061] (Adhesive and Other Components) The two-component curing adhesive of the present invention may contain components other than those described above. The other components may be contained in either or both of the polyol composition (X) and the polyisocyanate composition (Y), or may be prepared separately from these and mixed with the polyol composition (X) and the polyisocyanate composition (Y) immediately before application of the adhesive. Each component will be described below.

[0062] (Coupling Agent (E)) The adhesive of the present invention may contain a coupling agent (E). This makes it possible to provide an adhesive with better moldability. The effect of the coupling agent (E) is particularly effective when the aluminum foil has not been subjected to a chemical conversion treatment. Examples of the coupling agent (E) include a silane coupling agent (E1), a titanate-based coupling agent (E2), and an aluminum-based coupling agent (E3). The coupling agent (E) may be added to the polyol composition (X) or the polyisocyanate composition (Y). It may be added when mixing the polyol composition (X) and the polyisocyanate composition (Y).

[0063] Examples of the silane coupling agent (E1) include aminosilanes such as γ-aminopropyltriethoxysilane, γ-aminopropyltrimethoxysilane, N-β(aminoethyl)-γ-aminopropyltrimethoxysilane, N-β(aminoethyl)-γ-aminopropyltrimethyldimethoxysilane, and N-phenyl-γ-aminopropyltrimethoxysilane; epoxysilanes such as β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, and glycidoxyoctyltrimethoxysilane; vinyltris(β-methoxyethyl)silane; vinylsilanes such as vinyltriethoxysilane, vinyltrimethoxysilane, octenyltrimethoxysilane, γ-methacryloxypropyltrimethoxysilane, and methacryloxyoctyltrimethoxysilane; polymeric silane coupling agents such as polymeric epoxysilanes in which multiple alkoxysilyl groups and multiple epoxy groups are introduced into the polymer backbone, and polymeric aminosilanes in which multiple alkoxysilyl groups and multiple amino groups are introduced into the polymer backbone; hexamethyldisilazane, γ-mercaptopropyltrimethoxysilane, and 3-isocyanatopropyltriethoxysilane. These silane coupling agents (E1) can be used alone or in combination of two or more.

[0064] Examples of the titanate coupling agent (E2) include tetraisopropoxytitanium, tetra-n-butoxytitanium, butyl titanate dimer, tetrastearyl titanate, titanium acetylacetonate, titanium lactate, tetraoctylene glycol titanate, titanium lactate, and tetrastearoxytitanium.

[0065] Examples of the aluminum-based coupling agent (E3) include acetoalkoxyaluminum diisopropylate.

[0066] The amount of coupling agent (E) is preferably 0.1 parts by mass or more, more preferably 0.3 parts by mass or more, more preferably 0.5 parts by mass or more, and even more preferably 0.7 parts by mass or more, per 100 parts by mass of the solid content of polyol composition (X). This makes it possible to more reliably improve moldability. Furthermore, since the degree of improvement in moldability decreases when the content of coupling agent (E) exceeds a certain amount, there are no particular restrictions, but it is preferably 10 parts by mass or less, more preferably 8 parts by mass or less, and even more preferably 5 parts by mass or less, per 100 parts by mass of the solid content of polyol composition (X).

[0067] (Epoxy Resin (F)) The adhesive may contain an epoxy resin (F). When the adhesive contains an epoxy resin (F), a laminate having excellent moldability and initial adhesive strength can be obtained. Examples of epoxy resins include bisphenol-type epoxy resins such as bisphenol A-type epoxy resins and bisphenol F-type epoxy resins; biphenyl-type epoxy resins such as biphenyl-type epoxy resins and tetramethylbiphenyl-type epoxy resins; and dicyclopentadiene-phenol addition reaction type epoxy resins. It is preferable to use an epoxy resin having a number average molecular weight (Mn) of 300 to 2,000. It is also preferable to use an epoxy resin having an epoxy equivalent of 150 to 1,000 g / equivalent. The amount of epoxy resin blended is preferably 30% by mass or less of the solid content of the polyol composition (X).

[0068] (Tackifier (G)) The adhesive may contain a tackifier (G). The tackifier (G) may be added to the polyol composition (X), the polyisocyanate composition (Y), or when these are mixed. Examples of the tackifier (G) include rosin-based or rosin ester-based tackifiers, terpene-based or terpene phenol-based tackifiers, saturated hydrocarbon resins, coumarone-based tackifiers, coumarone-indene-based tackifiers, styrene resin-based tackifiers, xylene resin-based tackifiers, phenol resin-based tackifiers, petroleum resin-based tackifiers, and ketone resin-based tackifiers. These may be used alone or in combination of two or more. Tackifiers with various softening points can be obtained, mainly depending on the molecular weight. However, from the viewpoints of compatibility when mixed with other resins constituting the polyol composition (X), color tone, thermal stability, etc., it is preferable that the softening point be 10 to 160°C. It is preferably used in an amount of 1 to 30 parts by mass (solid content), and more preferably 3 to 20 parts by mass (solid content), per 100 parts by mass of the solid content of the resin constituting the polyol composition (X).

[0069] (Phosphoric Acid or Derivative thereof (H)) The adhesive may contain a phosphoric acid or a derivative thereof (H). This improves initial adhesion and can suppress problems such as tunneling. The phosphoric acid or a derivative thereof (H) may be added to the polyol composition (X) or the polyisocyanate composition (Y). It may also be added when these are mixed.

[0070] Examples of the phosphoric acid or derivative thereof (H) include phosphoric acids such as hypophosphorous acid, phosphorous acid, orthophosphoric acid, and hypophosphoric acid; condensed phosphoric acids such as metaphosphoric acid, pyrophosphoric acid, tripolyphosphoric acid, polyphosphoric acid, and ultraphosphoric acid; monomethyl orthophosphate, monoethyl orthophosphate, monopropyl orthophosphate, monobutyl orthophosphate, mono-2-ethylhexyl orthophosphate, monophenyl orthophosphate, monomethyl phosphite, monoethyl phosphite, monopropyl phosphite, monobutyl phosphite, mono-2-ethylhexyl phosphite, monophenyl phosphite; Examples of suitable phosphate esters include mono- and diesters of di-2-ethylhexyl orthophosphate, diphenyl orthophosphate, dimethyl phosphite, diethyl phosphite, dipropyl phosphite, dibutyl phosphite, di-2-ethylhexyl phosphite, diphenyl phosphite, and the like; mono- and diesters of condensed phosphoric acid and alcohols; products obtained by adding an epoxy compound such as ethylene oxide or propylene oxide to the above-mentioned phosphoric acids; and epoxy phosphate esters obtained by adding the above-mentioned phosphoric acids to aliphatic or aromatic diglycidyl ethers, and two or more of these can also be used in combination.

[0071] The adhesive may be either a solvent-based or solventless type. In the case of a solvent-based adhesive, at least one of the polyol composition (X) and the polyisocyanate composition (Y) contains an organic solvent such as an ester (e.g., ethyl acetate, butyl acetate, cellosolve acetate), a ketone (e.g., acetone, methyl ethyl ketone, isobutyl ketone, cyclohexanone), an ether (e.g., tetrahydrofuran, dioxane), an aromatic hydrocarbon (e.g., toluene, xylene), a halogenated hydrocarbon (e.g., methylene chloride, ethylene chloride), or dimethyl sulfoxide or dimethyl sulfamide, in which the above-mentioned components are dissolved. These organic solvents may be those used as reaction media in the production of the above-mentioned components, or may be added separately.

[0072] In the case of a solventless adhesive, the adhesive does not substantially contain any of the organic solvents listed above. Note that if the organic solvent used as a reaction medium during the production of each component of the adhesive is not completely removed and remains, the adhesive is considered to be substantially free of organic solvent.

[0073] In addition, the two-component adhesive may contain various additives such as ultraviolet absorbers, antioxidants, silicon-based additives, fluorine-based additives, rheology control agents, defoamers, antistatic agents, and antifogging agents.

[0074] The polyol composition (X) and the polyisocyanate composition (Y) are preferably used in such a ratio that the mass ratio of the total mass of the solid contents of the polyester polyol (A) and the urethane resin (B) contained in the polyol composition (X) to the solid content (or non-volatile content) of the polyisocyanate composition (Y) is 1 to 20, and more preferably 3 to 10.

[0075] <Laminate> The adhesive of the present invention can be suitably used for the production of laminates requiring heat resistance and moldability, but is not limited thereto, and can be suitably used for the production of various laminates. The laminate of the present invention is obtained by laminating a first substrate and a second substrate with the adhesive of the present invention. The method for producing the laminate is not particularly limited. As an example, when the two-component curing adhesive is solvent-based, the adhesive of the present invention is applied to either the first substrate or the second substrate by extrusion, gravure coating, roll coating, or the like, and the organic solvent is evaporated, followed by lamination of the other substrate. When the adhesive is solventless, the two-component curing adhesive is applied to either the first substrate or the second substrate, followed by lamination of the other substrate. The temperature of the laminating roll when laminating the substrates is, for example, 40°C to 120°C. It is preferable to perform lamination at a laminating roll temperature of 40 to 90°C, as this results in a laminate with better moldability. The pressure of the laminating roll is 3 to 300 kg / cm. ２ After laminating the laminate, the laminate is aged at room temperature to 100°C, more preferably at 40 to 100°C, for 2 days to 2 weeks to harden the adhesive, thereby obtaining a laminate. The amount of adhesive to be applied can be adjusted as appropriate, but as an example, it is 1.5 g / m ２ ~10.0g / m ２ is.

[0076] The substrate to be used is not particularly limited, and can be appropriately selected depending on the application. For example, for food packaging, polyethylene terephthalate (PET) film, polystyrene film, polyamide film, polyacrylonitrile film, polyethylene film (LLDPE: low-density polyethylene film, HDPE: high-density polyethylene film, MDOPE: uniaxially oriented polyethylene film, OPE: biaxially oriented polyethylene film), polypropylene film (CPP: unoriented polypropylene film, OPP: biaxially oriented polypropylene film), polyolefin film such as a gas barrier heat seal film in which an olefin-based heat sealable resin layer is provided on one or both sides of a resin having gas barrier properties such as an ethylene-vinyl alcohol copolymer or polyvinyl alcohol, polyvinyl alcohol film, ethylene-vinyl alcohol copolymer film, etc. can be mentioned.

[0077] It is also preferable to use a film made of a material containing biomass-derived components. 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.

[0078] 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.

[0079] Alternatively, products using biomass raw materials classified by the biomass plastic content specified in ISO 16620 or ASTM D6866 are also on the market. Radioactive carbon-14C exists in the atmosphere at a rate of 1 in 1012 particles, and this rate is the same for atmospheric carbon dioxide, so this rate 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 in the resin, i.e., the biomass plastic content, can be determined. Examples of plant-derived low-density polyethylene, which 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.

[0080] The film may be one that has been subjected to a stretching treatment. 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 that combines longitudinal stretching utilizing the speed difference between rolls and transverse stretching using a tenter is often used.

[0081] The film surface may be subjected to various surface treatments such as flame treatment and corona discharge treatment as necessary so that an adhesive layer without defects such as film breakage or repellency is formed.

[0082] Alternatively, a film laminated with a vapor-deposited layer of a metal such as aluminum or a metal oxide such as silica or alumina, or a barrier film containing a gas barrier layer of polyvinyl alcohol, an ethylene-vinyl alcohol copolymer, vinylidene chloride, etc. Use of such a film can provide a laminate with barrier properties against water vapor, oxygen, alcohol, inert gases, volatile organic compounds (fragrances), etc.

[0083] The paper can be made from any known paper base material without any particular limitations. Specifically, it is produced using natural fibers for papermaking, such as wood pulp, on a known papermaking machine, but the papermaking conditions are not particularly specified. Examples of natural fibers for papermaking include wood pulp, such as softwood pulp and hardwood pulp; non-wood pulp, such as Manila hemp pulp, sisal hemp pulp, and flax pulp; and pulp obtained by chemically modifying these pulps. Examples of pulp that can be used include chemical pulp produced by sulfate cooking, acidic, neutral, or alkaline sulfite cooking, soda cooking, ground pulp, chemi-ground pulp, and thermomechanical pulp. Various commercially available fine paper, coated paper, lined paper, impregnated paper, cardboard, and paperboard can also be used.

[0084] More specific examples of the laminate configuration include, but are not limited to, (1) substrate 1 / adhesive layer 1 / sealant film (2) substrate 1 / adhesive layer 1 / metal-deposited unstretched film (3) substrate 1 / adhesive layer 1 / metal-deposited stretched film (4) transparent vapor-deposited stretched film / adhesive layer 1 / sealant film (5) substrate 1 / adhesive layer 1 / substrate 2 / adhesive layer 2 / sealant film (6) substrate 1 / adhesive layer 1 / metal-deposited stretched film / adhesive layer 2 / sealant film (7) substrate 1 / adhesive layer 1 / transparent vapor-deposited stretched film / adhesive layer 2 / sealant film (8) substrate 1 / adhesive layer 1 / metal layer / adhesive layer 2 / sealant film (9) substrate 1 / adhesive layer 1 / substrate 2 / adhesive layer 2 / metal layer / adhesive layer 3 / sealant film (10) substrate 1 / adhesive layer 1 / metal layer / adhesive layer 2 / substrate 2 / adhesive layer 3 / sealant film.

[0085] Examples of the substrate 1 used in structure (1) include MDOPE film, OPE film, OPP film, PET film, nylon film, paper, and the like. Furthermore, the substrate 1 may be coated to improve gas barrier properties or ink receptivity when a printing layer (described later) is provided. Commercially available coated substrate films 1 include K-OPP film, K-PET film, and K-nylon film. The adhesive layer 1 is a cured coating of the adhesive of the present invention. Examples of sealant films include CPP film, LLDPE film, easy-open heat seal film, and gas barrier heat seal film. A printing layer may be provided on the surface of the substrate 1 facing the adhesive layer 1 (when a coated substrate film 1 is used, the surface of the coating layer facing the adhesive layer 1) or on the surface opposite the adhesive layer 1. The printing layer is formed using various printing inks, such as gravure ink, flexographic ink, offset ink, stencil ink, and inkjet ink, using a common printing method conventionally used for printing on polymer films and paper.

[0086] Examples of the substrate 1 used in structures (2) and (3) include an MDOPE film, an OPE film, an OPP film, a PET film, and paper. The adhesive layer 1 is a cured coating of the adhesive of the present invention. Examples of metal-vapor-deposited unstretched films include a CPP film, an LLDPE film, and a VM-CPP film or a VM-LLDPE film obtained by vapor-depositing a metal such as aluminum on a gas-barrier heat-sealable film. Examples of metal-vapor-deposited stretched films include a VM-MDOPE film, a VM-OPE film, or a VM-OPP film obtained by vapor-depositing a metal such as aluminum on an MDOPE film, an OPE film, or an OPP film. As in structure (1), a printed layer may be provided on either side of the substrate 1.

[0087] Examples of transparent vapor-deposited stretched films used in structure (4) include films obtained by depositing silica or alumina on MDOPE film, OPE film, OPP film, PET film, nylon film, etc. A film with a coating applied to the inorganic vapor-deposited layer of silica or alumina may also be used for the purpose of protecting the inorganic vapor-deposited layer. The adhesive layer 1 is a cured coating of the adhesive of the present invention. Examples of sealant films include those similar to those in structure (1). A printed layer may be provided on the surface of the transparent vapor-deposited stretched film facing the adhesive layer 1 (when a film with a coating applied to the inorganic vapor-deposited layer is used, the surface of the coating layer facing the adhesive layer 1). The method of forming the printed layer is the same as in structure (1).

[0088] Examples of the substrate 1 used in structure (5) include PET film and paper. Examples of the substrate 2 include nylon film. At least one of the adhesive layer 1 and the adhesive layer 2 is a cured coating film of the adhesive of the present invention. Examples of the sealant film include those similar to those in structure (1). As in structure (1), a printed layer may be provided on either side of the substrate 1.

[0089] Examples of the substrate 1 in structure (6) include those similar to those in structures (2) and (3). Examples of metal-vapor-deposited stretched films include VM-MDOPE films, VM-OPE films, VM-OPP films, and VM-PET films, which are MDOPE films, OPE films, OPP films, and PET films that have been subjected to metal vapor deposition of aluminum or the like. At least one of the adhesive layers 1 and 2 is a cured coating film of the adhesive of the present invention. Examples of the sealant film include those similar to those in structure (1). As in structure (1), a printed layer may be provided on either side of the substrate 1.

[0090] Examples of the substrate 1 in structure (7) include PET film, paper, etc. Examples of the transparent vapor-deposited stretched film include those similar to those in structure (4). At least one of the adhesive layers 1 and 2 is a cured coating film of the adhesive of the present invention. Examples of the sealant film include those similar to those in structure (1). As in structure (1), a printed layer may be provided on either side of the substrate 1.

[0091] Examples of the substrate 1 in structure (8) include PET film and paper. Examples of the metal layer include aluminum foil. At least one of the adhesive layers 1 and 2 is a cured coating film of the adhesive of the present invention. Examples of the sealant film include those similar to those in structure (1). As in structure (1), a printed layer may be provided on either side of the substrate 1.

[0092] Examples of the substrate 1 in structures (9) and (10) include PET film, paper, etc. Examples of the substrate 2 include nylon film, etc. Examples of the metal layer include aluminum foil, etc. At least one layer of the adhesive layers 1, 2, and 3 is a cured coating film of the adhesive of the present invention. Examples of the sealant film include those similar to those in structure (1). As in structure (1), a printed layer may be provided on either side of the substrate 1.

[0093] The laminate of the present invention may further include other films or substrates in addition to the above-described configurations (1) to (10). As the other substrates, in addition to the above-described stretched films, unstretched films, and transparent vapor-deposited films, porous substrates such as paper, wood, and leather, which will be described later, can also be used. The adhesive used to bond the other substrates may or may not be the adhesive of the present invention.

[0094] The "other layer" may contain known additives or stabilizers, such as antistatic agents, adhesion-enhancing coating agents, plasticizers, lubricants, antioxidants, etc. Furthermore, the "other layer" may be a film whose surface has been pretreated with corona treatment, plasma treatment, ozone treatment, chemical treatment, solvent treatment, or the like in order to improve adhesion when laminated with other materials.

[0095] The laminate of the present invention can be suitably used for a variety of applications, such as packaging materials for food, medicines, and daily necessities; lid materials; paper tableware such as paper straws, paper napkins, paper spoons, paper plates, and paper cups; barrier materials; roofing materials; solar cell panel materials; battery packaging materials; window materials; outdoor flooring materials; lighting protection materials; automotive components; signs; stickers and other outdoor industrial applications; decorative sheets used in simultaneous injection molding decoration methods; and packaging materials for liquid laundry detergents, liquid kitchen detergents, liquid bath detergents, liquid bath soaps, liquid shampoos, liquid conditioners, and the like.

[0096] <Packaging Material> The laminate of the present invention can be used as a multilayer packaging material for protecting foods, medicines, etc. When used as a multilayer packaging material, the layer structure can be changed depending on the contents, the environment of use, and the form of use. In addition, the packaging of the present invention may be appropriately provided with an easy-open treatment or a resealable means.

[0097] A specific example of the packaging material of the present invention is a packaging material obtained by forming a bag from a laminate having a sealant film, such as the laminate configuration examples (1), (4), and (10) described above. The laminate is folded or overlapped so that the inner layer surfaces (the surfaces of the sealant film) face each other, and the peripheral edges are heat-sealed to form a bag. Examples of bag-making methods include heat-sealing methods using a side seal, two-sided seal, three-sided seal, four-sided seal, envelope seal, flared seal, flat-bottom seal, square-bottom seal, gusset seal, or other heat seal types. The packaging material of the present invention can take various forms depending on the contents, usage environment, and usage pattern. Self-standing packaging materials (standing pouches) are also possible. Examples of heat-sealing methods include known methods such as bar seal, rotary roll seal, belt seal, impulse seal, high-frequency seal, and ultrasonic seal.

[0098] The packaging material of the present invention is filled with contents through its opening, and then the opening is heat-sealed to produce a product using the packaging material of the present invention. Examples of contents to be filled include foods such as rice crackers, bean snacks, nuts, biscuits, cookies, wafer snacks, marshmallows, pies, semi-dried cakes, candies, and snacks; staple foods such as bread, snack noodles, instant noodles, dried noodles, pasta, aseptically packaged cooked rice, porridge, rice porridge, packaged rice cakes, and cereal foods; processed agricultural products such as pickles, boiled beans, natto, miso, frozen tofu, tofu, nametake mushrooms, konjac, processed wild vegetables, jams, peanut cream, salads, frozen vegetables, and processed potatoes; processed livestock products such as ham, bacon, sausages, processed chicken, and corned beef; and processed fish ham and meat products. Examples of such foods include processed seafood products such as sausages, fish paste products, kamaboko, nori seaweed, tsukudani (simmered foods in soy sauce), bonito flakes, salted fish, smoked salmon, and spicy mentaiko; fruit pulp such as peaches, mandarin oranges, pineapples, apples, pears, and cherries; vegetables such as corn, asparagus, mushrooms, onions, carrots, radishes, and potatoes; cooked foods such as frozen and chilled prepared dishes, including hamburgers, meatballs, fried seafood, gyoza, and croquettes; dairy products such as butter, margarine, cheese, cream, instant creamy powder, and infant formula; liquid seasonings, retort curry, and pet food.

[0099] In addition, the present invention can also be used as a packaging material for various non-food products, such as cigarettes, disposable body warmers, medicines such as infusion packs, liquid laundry detergent, liquid kitchen detergent, liquid bath detergent, liquid bath soap, liquid shampoo, liquid conditioner, cosmetics such as lotion and emulsion, vacuum insulation materials, batteries, etc.

[0100] <Laminate for blister packs> The laminate for blister packs of the present invention comprises a first substrate, a first adhesive layer, an aluminum foil, a second adhesive layer, and a second substrate laminated in this order, and at least one of the first adhesive layer and the second adhesive layer is a cured coating film of the adhesive of the present invention. Both the first adhesive layer and the second adhesive layer may be a cured coating film of the adhesive of the present invention. In this specification, the laminate for blister packs refers to a laminate used to form a blister pack before the contents are sealed inside.

[0101] (First substrate) The first substrate is an outer layer of the laminate of the present invention (a layer disposed on the opposite side of the aluminum foil from the contents), and is made of a film having excellent puncture resistance. Specific examples of the substrate film include a polyamide film and a polyester film.

[0102] The polyamide film is not particularly limited, and conventionally known films can be used, such as poly(4-aminobutyric acid) [nylon 4], poly(6-aminohexanoic acid) [nylon 6, or poly(caprolactam)], poly(7-aminoheptanoic acid) [nylon 7], poly(8-aminooctanoic acid) [nylon 8], poly(9-aminononanoic acid) [nylon 9], poly(10-aminodecanoic acid) [nylon 10], poly(11-aminoundecanoic acid) [nylon 11], poly(12-aminododecanol) [nylon 12], and the like. Homopolymers such as nylon 4,6, poly(hexamethylene adipamide) [nylon 6,6], poly(hexamethylene sebacamide) [nylon 6,10], poly(heptamethylene pimelamide) [nylon 7,7], poly(octamethylene suberamide) [nylon 8,8], poly(hexamethylene azelamide) [nylon 6,9], poly(nonamethylene azelamide) [nylon 9,9], poly(decamethylene azelamide) [nylon 10,9], poly(tetramethyl azelamide) [nylon 11,12], Polyamide of n-dodecanedioic acid and hexamethylenediamine [nylon 6,12], polyamide of dodecanedioic acid and n-dodecanedioic acid [nylon 12,12], caprolactam / hexamethylene adipamide copolymer [nylon 6,6 / 6], hexamethylene adipamide / caprolactam copolymer [nylon 6 / 6,6], trimethylene adipamide / hexamethylene azelaamide copolymer [nylon ... hexamethylene adipamide / hexamethylene-azelaamide caprolactam copolymer [nylon 6,6 / 6,9 / 6], poly(tetramethylenediamine-co-isophthalic acid) [nylon 4,I], polyhexamethylene isophthalamide [nylon 6,1], hexamethylene adipamide / hexamethylene-isophthalamide [nylon 6,6 / 6I], hexamethylene adipamide / hexamethylene terephthalamide [nylon 6,6 / 6T], poly(2,2,Examples of suitable polyamide copolymers include poly(2-trimethylhexamethylene terephthalamide), poly(m-xylylene adipamide) [MXD6], poly(p-xylylene adipamide), poly(hexamethylene terephthalamide), poly(dodecamethylene terephthalamide), polyamide 6T / 6I, polyamide 6 / MXDT / I, and polyamide MXDI. Preferred are nylon 6, nylon 6,6, nylon 6 / 6,6, or mixtures thereof.

[0103] Examples of polyester films include polyethylene terephthalate and glycol-modified polyethylene terephthalate.

[0104] The film thickness of the first substrate is not particularly limited, but from the viewpoint of a balance between formability and puncture resistance, it is preferably 10 μm or more and 50 μm or less, and more preferably 20 μm or more and 45 μm or less. The first substrate is produced by a tubular method or a tenter method and is produced by biaxial stretching. The stretching method may be simultaneous biaxial stretching or sequential biaxial stretching.

[0105] (Aluminum Foil) As the aluminum foil, a soft material made of pure aluminum or an aluminum-iron alloy can be used. Specific examples of the alloy include alloy numbers 8079 and 8021. The thickness of the aluminum foil can be adjusted as appropriate, but from the viewpoint of the balance between formability and moisture resistance, it is preferably 15 μm or more and 80 μm or less, and more preferably 20 μm or more and 60 μm or less.

[0106] The aluminum foil may be chemically treated on one or both surfaces. Examples of chemical treatments include undercoat treatment using a coupling agent such as a silane coupling agent or a titanium coupling agent, and chromate treatment. Examples of chromate treatments include a method of applying a composition containing, for example, phosphoric acid, at least one of chromic acid and chromium (III) salt, and at least one selected from the group consisting of a metal salt of fluoride, a non-metal salt of fluoride, an acrylic resin, a chitosan derivative resin, and a phenolic resin to the surface of the degreased aluminum foil, and then drying the composition.

[0107] (Second Base Material) The second base material may be a polypropylene film, a polyvinyl chloride film, or a polyvinylidene chloride film. The thickness of the second base material is, for example, 20 μm or more and 150 μm or less.

[0108] When the second substrate is a polyvinyl chloride film or a polyvinylidene chloride film, a heat seal layer may be provided on the surface of the second substrate opposite to the surface on which the adhesive layer is provided. The heat seal layer can be formed, for example, by applying a heat seal agent containing a heat sealable resin and a solvent to the second substrate and then drying the solvent.

[0109] Examples of heat-sealable resins include thermoplastic resins such as shellacs, rosins, rosin-modified maleic acid resins, rosin-modified phenolic resins, nitrocellulose, cellulose acetate, cellulose acetyl propionate, cellulose acetyl butyrate, chlorinated rubber, cyclized rubber, vinyl chloride, vinylidene chloride, polyamide resins, vinyl chloride-vinyl acetate copolymers, polyester resins, ketone resins, butyral resins, chlorinated polypropylene resins, chlorinated polyethylene resins, chlorinated ethylene vinyl acetate resins, ethylene vinyl acetate resins, acrylic resins, urethane resins, ethylene-vinyl alcohol resins, styrene-maleic acid resins, casein, and alkyd resins, and these may be used alone or in combination of two or more.

[0110] The heat sealing agent may be in any form, such as a type in which these resins are dissolved in an organic solvent, a type in which these resins are dissolved in water or an aqueous organic solvent, or an emulsion type in which an acrylic emulsion, a urethane emulsion, a polyvinyl alcohol resin, an ethylene-vinyl alcohol emulsion, an ethylene-methacrylic acid emulsion, a polyolefin emulsion, an ethylene vinyl acetate emulsion, or the like is dispersed in water or an aqueous organic solvent.

[0111] The organic solvent is not particularly limited, and examples thereof include various organic solvents such as aromatic hydrocarbons such as toluene, xylene, Solvesso #100, and Solvesso #150; aliphatic hydrocarbons such as hexane, heptane, octane, and decane; and esters such as methyl acetate, ethyl acetate, isopropyl acetate, butyl acetate, amyl acetate, ethyl formate, and butyl propionate.

[0112] Examples of aqueous organic solvents include alcohols such as methanol, ethanol, propanol, and butanol; ketones such as acetone, methyl ethyl ketone, and cyclohexanone; and glycol ethers such as ethylene glycol (mono, di)methyl ether, ethylene glycol (mono, di)ethyl ether, ethylene glycol monopropyl ether, ethylene glycol monoisopropyl ether, monobutyl ether, diethylene glycol (mono, di)methyl ether, diethylene glycol (mono, di)ethyl ether, diethylene glycol monoisopropyl ether, diethylene glycol monobutyl ether, triethylene glycol (mono, di)methyl ether, propylene glycol (mono, di)methyl ether, propylene glycol monopropyl ether, propylene glycol monobutyl ether, and dipropylene glycol (mono, di)methyl ether.

[0113] The heat-sealing agent may contain components other than the heat-sealable resin and solvent, such as wax, filler, antifoaming agent, viscosity modifier, leveling agent, tackifier, preservative, antibacterial agent, rust inhibitor, antioxidant, etc.

[0114] The heat sealing agent can be applied by any known method, such as a roll coater, gravure coater, flexo coater, air doctor coater, blade coater, air knife coater, squeeze coater, impregnation coater, transfer roll coater, kiss coater, curtain coater, cast coater, spray coater, die coater, offset printing machine, screen printing machine, etc. After coating, a drying step in an oven or the like can be performed.

[0115] The thickness of the heat seal layer (the amount of heat sealant applied (solid content)) may be any value. For example, it is 0.5 g / m ２ ~5g / m ２ is.

[0116] (Adhesive Layer) At least one of the first adhesive layer and the second adhesive layer is a cured coating film of the adhesive of the present invention. Both the first adhesive layer and the second adhesive layer may be a cured coating film of the adhesive of the present invention, or only one of them may be a cured coating film of the adhesive of the present invention. When molding the laminate of the present invention, the first adhesive layer has a higher moldability requirement than the second adhesive layer. Therefore, it is preferable that the first adhesive layer is a cured coating film of the adhesive of the present invention.

[0117] When the second adhesive layer is not a cured coating film of the adhesive of the present invention, the adhesive used is not particularly limited as long as it is suitable for bonding an aluminum foil to a second substrate, and for example, a general-purpose two-component curing adhesive consisting of a polyol compound and a polyisocyanate compound, or a two-component curing adhesive consisting of an acid-modified polyolefin and a curing agent that can react with it can be used. Examples of curing agents that can react with acid-modified polyolefin include, but are not limited to, epoxy compounds and isocyanate compounds.

[0118] The thickness of the first adhesive layer is preferably 0.5 μm to 50 μm, more preferably 2 μm to 30 μm, from the viewpoint of a balance between adhesiveness and moldability. The thickness of the second adhesive layer is preferably 0.5 μm to 50 μm, more preferably 2 μm to 30 μm, from the viewpoint of a balance between adhesiveness and moldability.

[0119] (Method of Manufacturing Blister Pack Laminate) The method of manufacturing the blister pack laminate of the present invention is not particularly limited. As an example, when the two-component curing adhesive is a solvent-based adhesive, it is manufactured by the following method. First, the above-mentioned two-component curing adhesive is applied to either the base film or the aluminum foil by extrusion, gravure coating, roll coating, or the like, and the organic solvent is evaporated, and then the other is laminated. Next, the two-component curing adhesive is applied to the aluminum foil, the organic solvent is evaporated, and then a sealant layer is laminated, followed by aging at room temperature to 90°C for 2 days to 2 weeks to cure the adhesive, thereby obtaining the blister pack laminate of the present invention. Alternatively, the base film and aluminum foil may be laminated together and then aged under the above-mentioned conditions, and then the aluminum foil and sealant layer may be laminated together and then aged.

[0120] When the adhesive is a solventless type, for example, a two-component curing adhesive is applied to either the base film or the aluminum foil, and then the base film and the aluminum foil are laminated together and aged for 2 days to 2 weeks at room temperature to 90° C. Next, the two-component curing adhesive is applied to the aluminum foil, and the aluminum foil and the sealant layer are laminated together, and the aging adhesive is cured under the same conditions to obtain the blister pack laminate of the present invention.

[0121] <Blister Pack> The blister pack of the present invention is obtained by molding the above-described laminate for blister packs. The blister pack may be obtained by molding the laminate for blister packs of the present invention to provide one or more pockets, and then laminating a conventionally known blister pack lid material (for example, aluminum foil coated with a heat sealant) to the molded laminate for blister packs. Alternatively, the blister pack may be obtained by preparing two laminates for blister packs of the present invention each having one or more pockets (in which case, at least one of the laminates has a heat seal layer on a second substrate), matching the pockets, and heat-sealing the heat seal layers together. Examples of molding methods include flat-plate air pressure molding, plug-assisted air pressure molding, drum vacuum molding, and plug molding.

[0122] The present invention will be described in more detail below with reference to specific synthesis examples and examples, but the present invention is not limited to these examples. In the following examples, "parts" and "%" represent "parts by mass" and "% by mass", respectively, unless otherwise specified.

[0123] <Preparation of Polyester Polyol (A)> (Synthesis Example 1) Synthesis of Polyester Polyol (A-1) A polyester reaction vessel equipped with a stirrer, thermometer, nitrogen gas inlet tube, rectification tube, water separator, etc. was charged with 227.5 parts of isophthalic acid, 204.8 parts of sebacic acid, 42.6 parts of ethylene glycol, 199.0 parts of neopentyl glycol, and 0.15 parts of a titanium catalyst, and the mixture was gradually heated so that the temperature at the top of the rectification tube did not exceed 100° C., and the internal temperature was maintained at 240° C. When the acid value reached 1.5 mgKOH / g, the pressure was reduced to 10 mmHg or less, and the mixture was maintained for 1.5 hours to complete the esterification reaction, thereby obtaining an intermediate polyester polyol (A'-1).

[0124] To 100 parts of the resulting intermediate polyester polyol (A'-1), 4.5 parts of isophorone diisocyanate was added, and the mixture was heated to 90°C to carry out a urethane reaction until substantially no free NCO groups remained, yielding a polyester polyurethane polyol. KBM-403 (a silane coupling agent manufactured by Shin-Etsu Chemical Co., Ltd.) was added in an amount of 1% by mass of the total amount of the polyester polyurethane polyol, and the mixture was diluted with ethyl acetate to obtain a polyester polyol (A-1) solution with a nonvolatile content of 65%.

[0125] <Preparation of Two-Component Curing Adhesive> (Example 1) A polyol composition (X-1) was prepared by thoroughly stirring 81 parts of a polyester polyol (A-1) solution and 58.5 parts of a urethane resin (B-1) solution. 11 parts of a toluene diisocyanate trimethylolpropane adduct (referred to as TDI-TMP in the table; NCO %: 13.3, nonvolatile content: 75%) was added as a polyisocyanate composition (Y) to ethyl acetate so that the nonvolatile content was 25%, and the mixture was thoroughly stirred to prepare the two-component curing adhesive of Example 1.

[0126] (Examples 2) to (Example 8) Two-component curing adhesives were prepared in the same manner as in Example 1, except that the urethane resin (B) used and the blending amount were changed as shown in Table 2. The urethane resins (B-1) to (B-4) in the table are summarized as follows: "Solid content ratio" in the table is the total solid content mass of the polyester polyol (A) and the urethane resin (B) / the solid content (non-volatile content) of the polyisocyanate composition (Y).

[0127]

[0128] Comparative Examples 1 to 8 Two-component curing adhesives of Comparative Examples 1 to 8 were prepared in the same manner as in the Examples, except that the following thermoplastic resins were used in place of urethane resin (B) in the proportions shown in Table 3. The thermoplastic resins used are summarized as follows: UE-3220: Polyester resin manufactured by Unitika Ltd. UE-3223: Polyester resin manufactured by Unitika Ltd. UE-3400: Polyester resin manufactured by Unitika Ltd. GK-880: Polyester resin manufactured by Toyobo Co., Ltd. GK-360: Polyester resin manufactured by Toyobo Co., Ltd.

[0129] <Production of laminate for blister pack> (Example 1) The adhesive of Example 1 was applied at 4 g / m to the matte side of an aluminum foil having a thickness of 40 μm using a dry laminator. ２ (solid content), and after the solvent was evaporated, a stretched polyamide film having a thickness of 25 μm was laminated to the glossy surface of the aluminum foil. Next, the adhesive of Example 1 was applied to the glossy surface of the aluminum foil using a dry laminator at a rate of 4 g / m. ２ After the solvent was evaporated, the laminate was attached to a 60 μm thick polyvinyl chloride film and aged at 80° C. for 4 days to cure the adhesive, thereby obtaining a laminate of Example 1.

[0130] (Example 2) to (Example 8), (Comparative Example 1) to (Comparative Example 8) Laminates were obtained in the same manner as in Example 1, except that the adhesives of Examples 2 to 8 and Comparative Examples 1 to 8 were used instead of the adhesive of Example 1.

[0131] <Evaluation> (Adhesion Strength 1) Using Shimadzu Corporation's Autograph AGS-J, the adhesion strength 1 between the polyamide film and the aluminum foil was evaluated under the conditions of a peel speed of 50 mm / min, a peel width of 15 mm, and a T-type peeling pattern, according to the following criteria, and the results are summarized in a table. ◯: Adhesion strength of 7 N / 15 mm or more △: Adhesion strength of 5 N / 15 mm or more but less than 7 N / 15 mm ×: Adhesion strength less than 5 N / 15 mm

[0132] (Adhesion Strength 2) Under the same conditions as for Adhesion Strength 1, adhesion strength 2 between the aluminum foil and the polyvinyl chloride film was evaluated according to the following criteria and summarized in a table. ◯: Adhesion strength is 6 N / 15 mm or more Δ: Adhesion strength is 5 N / 15 mm or more and less than 6 N / 15 mm ×: Adhesion strength is less than 5 N / 15 mm

[0133] (Moldability) Using a 1-ton benchtop servo press (SBN-1000) manufactured by Yamaoka Seisakusho Co., Ltd., the blister pack laminates of the Examples and Comparative Examples were cut into pieces measuring 60 x 60 mm. With the polyamide film facing the convex side, overhang molding was performed using a free-form straight mold at a molding height of 5 mm. Twenty samples were prepared, and each was examined for the presence or absence of aluminum foil breakage or lifting between layers. Moldability was evaluated based on the number of samples without these occurrences (pass rate). The punch shape of the mold used was a square with sides of 30 mm, a corner radius of 2 mm, and a punch shoulder radius of 1 mm. The die hole shape of the mold used was a square with sides of 34 mm, a die hole corner radius of 2 mm, and a die hole shoulder radius of 1 mm. The clearance between the punch and the die hole was 0.3 mm on each side. The clearance causes a slope depending on the molding height. 〇: Pass rate 80% or more △: Pass rate 60% or more but less than 80% ×: Pass rate less than 60%

[0134] (Heat resistance) The laminates of the examples or comparative examples were cut into a size of 60 x 60 mm, and with the polyamide film facing outward, they were subjected to overhang molding at a molding height of 5 mm using a free-form straight mold. 20 samples were prepared, and a heat seal bar was applied to the flange of each of the resulting 30 mm square trays at 180 ° C for 1 second so as to contact the side wall. The appearance near the boundary between the flange and the side wall on each side was confirmed, and the presence or absence of breakage of the aluminum foil and lifting between the stretched polyamide film and the aluminum foil was examined. The moldability was evaluated based on the number of samples (pass rate) that did not suffer from these problems. ◯: Pass rate 80% or more △: Pass rate 60% or more but less than 80% ×: Pass rate less than 60%

[0135]

[0136]

Claims

1. A two-component curing adhesive comprising a polyol composition (X) and a polyisocyanate composition (Y), wherein the polyol composition (X) comprises a polyester polyol (A) and a urethane resin (B) having a melting point of 0°C or higher and 60°C or lower, and the polyisocyanate composition (Y) comprises a polyisocyanate compound (D).

2. The two-component curing adhesive according to claim 1, wherein the heat of fusion of the urethane resin (B) is 10 mJ / mg or more and 80 mJ / mg or less.

3. The two-component curing adhesive according to claim 1, wherein the glass transition temperature of the urethane resin (B) is -10°C or lower.

4. A two-component curing adhesive as described in claim 1, wherein the proportion of the urethane resin (B) in the total amount of the polyester polyol (A) and the urethane resin (B) is 1 mass % or more and 30 mass % or less.

5. The two-component curing adhesive according to claim 1, further comprising a coupling agent (E).

6. A laminate comprising a first substrate, a second substrate, and an adhesive layer disposed between the first substrate and the second substrate, the adhesive layer being a cured coating film of the adhesive according to any one of claims 1 to 5.

7. A laminate for a blister pack, comprising a first substrate, a first adhesive layer, an aluminum foil, a second adhesive layer, and a second substrate laminated in this order, and at least one of the first adhesive layer and the second adhesive layer being a cured coating film of the adhesive according to any one of claims 1 to 5.

8. A packaging material obtained by molding the laminate according to claim 6.

9. A blister pack formed by molding the laminate for blister packs according to claim 7.

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