Adhesives, laminates, packaging materials

Abstract

Provided is a solvent-free two-component curable adhesive having excellent adhesive strength after a retort treatment even when a substrate having a metal foil such as an aluminum foil or a metal deposited layer of aluminum or the like is bonded to a plastic film.　This solvent-free two-component curable adhesive comprises a polyisocyanate composition (X) and a polyol composition (Y), wherein: the polyisocyanate composition (X) contains a polyurethane polyisocyanate (A1), which is a reaction product of a polyisocyanate (l) and a polyester polyol (m), and an acid anhydride (B); the acid value derived from the acid anhydride (B) in the polyisocyanate composition (X) is 1-100 mg KOH / g; the content of a diisocyanate monomer in the polyisocyanate composition (X) is at most 0.1 mass%; and the polyol composition (Y) contains a polyester polyol (C1).

Description

Technical Field

[0001] The present invention relates to a two-component curable adhesive, a laminate, and a packaging material.

Background Art

[0002] Laminates used for various packaging materials, labels, etc. are laminated with various substrates such as various plastic films, metal foils, papers, etc., and are given designability, functionality, storage properties, convenience, transport resistance, etc. The packaging material formed by molding the laminate into a bag shape is used as a packaging material in various fields including foods, pharmaceuticals, detergents, etc.

[0003] Conventionally, for laminate films, a two-component curable adhesive in which a polyisocyanate compound and a polyol compound are dissolved in a volatile organic solvent is applied to the film, the organic solvent is volatilized in the process of passing through an oven, and another film is laminated. The main method is to obtain it by the dry lamination method. However, in recent years, from the viewpoints of reducing environmental impact and improving the working environment, a two-component curable solventless adhesive in which a polyisocyanate compound and a polyol compound do not contain a volatile organic solvent has attracted attention (Patent Document 1, Patent Document 2).

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0005] When using a solvent-free, two-component curing adhesive like this to bond metal foils such as aluminum foil, or substrates with a metal vapor-deposited layer such as aluminum, to a plastic film, the adhesive strength after retort processing may be poor. In particular, if the contents contain acidic components such as vinegar, the adhesive strength after retort processing is significantly worse.

[0006] The present invention has been made in view of these circumstances, and aims to provide a solvent-free, two-component curing adhesive that exhibits excellent adhesive strength after retort treatment, even when a substrate having a metal foil such as aluminum foil or a metal vapor-deposited layer such as aluminum is bonded to a plastic film. The present invention also aims to provide a solvent-free, two-component curing adhesive that exhibits excellent adhesive strength after retort treatment, even when the contents contain a large amount of acidic components. [Means for solving the problem]

[0007] In other words, the present invention relates to a two-component, solvent-free adhesive comprising a polyisocyanate composition (X) and a polyol composition (Y), wherein the polyisocyanate composition (X) comprises polyurethane polyisocyanate (A1), which is a reaction product of polyisocyanate (l) and polyester polyol (m), and acid anhydride (B), the acid value derived from acid anhydride (B) in the polyisocyanate composition (X) is 1 mg KOH / g or more and 100 mg KOH / g or less, the content of diisocyanate monomer in the polyisocyanate composition (X) is 0.1% by mass or less, and the polyol composition (Y) contains polyester polyol (C1). [Effects of the Invention]

[0008] According to the present invention, it is possible to provide a solvent-free, two-component curing adhesive that exhibits excellent adhesive strength after retort treatment, even when a metal foil such as aluminum foil or a substrate having a metal vapor-deposited layer such as aluminum is bonded to a plastic film. [Modes for carrying out the invention]

[0009] <Adhesive> (Polyisocyanate composition (X)) (Polyurethane polyisocyanate (A1)) The polyisocyanate composition (X) used in the two-component curing adhesive of the present invention contains polyurethane polyisocyanate (A1), which is a reaction product of polyisocyanate (l) and polyol (m). The polyisocyanate (l) used in the synthesis of polyurethane polyisocyanate (A1) is not particularly limited, and conventionally known aromatic diisocyanates, aromatic aliphatic diisocyanates, aliphatic diisocyanates, alicyclic diisocyanates, and burette, nurate, adduct, allophanate, carbodiimide modified, uretdione modified forms of these diisocyanates can be used. One or more polyisocyanates can be used in combination.

[0010] Examples of aromatic diisocyanates include 2,2'-diphenylmethane diisocyanate, 2,4'-diphenylmethane diisocyanate, 4,4'-diphenylmethane diisocyanate (also known as MDI), polymethylene polyphenyl polyisocyanate (also called polymeric MDI or crude MDI), 1,3-phenylenediisocyanate, 4,4'-diphenyl diisocyanate, 1,4-phenylenediisocyanate (also known as PPDI), and 2,4-tolylene diisocyanate. Examples include, but are not limited to, annetes, 2,6-tolylene diisocyanate (also known as TDI), 4,4'-toluidine diisocyanate, 2,4,6-triisocyanate toluene, 1,3,5-triisocyanate benzene, tolidine diisocyanate (also known as TODI), dianisidine diisocyanate, naphthalene diisocyanate (also known as NDI), 4,4'-diphenyl ether diisocyanate, and 4,4',4"-triphenylmethane triisocyanate.

[0011] Aromatic aliphatic diisocyanates refer to aliphatic isocyanates having one or more aromatic rings in their molecule, and include, but are not limited to, m- or p-xylylene diisocyanate (also known as XDI) and α,α,α',α'-tetramethylxylylene diisocyanate (also known as TMXDI).

[0012] Examples of aliphatic diisocyanates include trimethylene diisocyanate, tetramethylene diisocyanate, hexamethylene diisocyanate (also known as HDI), pentamethylene diisocyanate (also known as PDI), 1,2-propylene diisocyanate, 2,3-butylene diisocyanate, 1,3-butylene diisocyanate, dodecamethylene diisocyanate, 2,4,4-trimethylhexamethylene diisocyanate, and lysine diisocyanate (also known as LDI), but are not limited to these.

[0013] Examples of alicyclic diisocyanates include, but are not limited to, 3-isocyanate-methyl-3,5,5-trimethylcyclohexyl isocyanate, isophorone diisocyanate (also known as IPDI), 1,3-cyclopentane diisocyanate, 1,3-cyclohexane diisocyanate, 1,4-cyclohexane diisocyanate, methyl-2,4-cyclohexane diisocyanate, methyl-2,6-cyclohexane diisocyanate, 4,4'-methylenebiscyclohexyl isocyanate (also known as hydrogenated MDI or HMDI), 1,3-bis(isocyanate-methyl)cyclohexane (also known as hydrogenated XDI or HXDI), hydrogenated TMXDI, norbornane diisocyanate (also known as NBDI), etc.

[0014] The polyisocyanate (l) is preferably at least one selected from aromatic diisocyanates, aromatic aliphatic diisocyanates, and alicyclic diisocyanates, and more preferably at least one selected from toluene diisocyanate, xylene diisocyanate, and isophorone diisocyanate. Since MDI is highly reactive in the process of dissolving the acid anhydride at high temperatures and there is a concern about side reactions, it is preferable not to include MDI.

[0015] The polyol (m) is not particularly limited and includes glycols such as ethylene glycol, 1,2-propanediol, 1,3-propanediol, 2-methyl-1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 3-methyl-1,5-pentanediol, 1,6-hexanediol, neopentyl glycol, dimethylbutanediol, butylethylpropanediol, diethylene glycol, triethylene glycol, tetraethylene glycol, dipropylene glycol, tripropylene glycol, bishydroxyethoxybenzene, 1,4-cyclohexanediol, and 1,4-cyclohexanedimethanol;

[0016] Trifunctional or tetrafunctional aliphatic alcohols such as glycerin, trimethylolpropane, and pentaerythritol; Bisphenols such as bisphenol A, bisphenol F, hydrogenated bisphenol A, and hydrogenated bisphenol F; Dimer All;

[0017] Polyether polyols obtained by addition polymerization of alkylene oxides such as ethylene oxide, propylene oxide, butylene oxide, styrene oxide, epichlorohydrin, tetrahydrofuran, and cyclohexylene in the presence of polymerization initiators such as glycols and trifunctional or tetrafunctional aliphatic alcohols;

[0018] Polyester polyols are reaction products of polyhydric alcohols such as glycols and trifunctional or tetrafunctional aliphatic alcohols with polyhydric carboxylic acids; A polyether polyester polyol which is a reaction product of a polyether polyol and a polyvalent carboxylic acid;

[0019] A polyurethane polyol which is a reaction product of a polyhydric alcohol such as a glycol, a trifunctional or tetrafunctional aliphatic alcohol, etc. and a polyisocyanate; A polyether polyurethane polyol which is a reaction product of a polyether polyol and a polyisocyanate; A polyester polyurethane polyol which is a reaction product of a polyester polyol and a polyisocyanate; etc. are mentioned, and one kind or a combination of two or more kinds can be used.

[0020] Examples of the polyvalent carboxylic acid used in the synthesis of the polyester polyol include aromatic polybasic acids such as phthalic acid, terephthalic acid, isophthalic acid, phthalic anhydride, 1,4-naphthalenedicarboxylic acid, 2,5-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, 2,3-naphthalenedicarboxylic anhydride, naphthoic 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, tetrabromophthalic anhydride, etc.; Methyl esterified products of aromatic polybasic acids such as dimethyl terephthalic acid, dimethyl 2,6-naphthalenedicarboxylate, etc.;

[0021] Aliphatic polybasic acids such as malonic acid, succinic acid, succinic anhydride, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, fumaric acid, maleic acid, maleic anhydride, itaconic acid, etc.; Alkyl esterified products of aliphatic polybasic acids such as dimethyl malonate, diethyl malonate, dimethyl succinate, dimethyl glutarate, dimethyl adipate, diethyl pimelate, diethyl sebacate, dimethyl fumarate, diethyl fumarate, dimethyl maleate, diethyl maleate, etc.;

[0022] Examples include 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, hymic anhydride, hettic anhydride, and other alicyclic polybasic acids, which can be used individually or in combination of two or more.

[0023] The polycarboxylic acid preferably includes an aromatic polycarboxylic acid. The amount of aromatic polycarboxylic acid in the polycarboxylic acid can be adjusted as appropriate depending on the purpose, but as an example, it is preferably 20% by mass or more, and preferably 30% by mass or more. The entire amount of polycarboxylic acid may also be aromatic polycarboxylic acid.

[0024] Polyisocyanates used in the synthesis of polyurethane polyols can be the same as those exemplified as polyisocyanate (l), either alone or in combination.

[0025] The polyol (m) is preferably at least one selected from polyester polyols and polyether polyols.

[0026] The molecular weight of the polyol (m) is preferably 300 g / mol or more and 3000 g / mol or less, and more preferably 400 g / mol or more and 2000 g / mol or less.

[0027] Polyurethane polyisocyanate (A1) is obtained by reacting a polyisocyanate (l) as exemplified above with a polyol (m) under conditions in which the isocyanate groups of polyisocyanate (m) are in excess of the active hydrogen groups of polyester polyol (m). The equivalent ratio of isocyanate groups to active hydrogen groups [NCO] / [active hydrogen groups] can be adjusted as appropriate, but as an example, it is between 2.0 and 20.0.

[0028] (Isocyanate derivative (A2)) The polyisocyanate composition (X) used in the present invention may contain isocyanate derivatives (A2) other than polyurethane polyisocyanate (A1). Examples of such isocyanate derivatives (A2) include bilets, nurates, allophanates, carbodiimide modified forms, uretdione modified forms, and polyurethane polyisocyanates of diisocyanate monomers such as aromatic diisocyanates, aromatic aliphatic diisocyanates, aliphatic diisocyanates, and alicyclic diisocyanates, which were exemplified as raw materials for polyurethane polyisocyanate (A1).

[0029] When the polyisocyanate composition (X) contains an isocyanate derivative (A2), it is preferable that the proportion of polyurethane polyisocyanate (A1) in the isocyanate group-containing compound (polyurethane polyisocyanate (A1) and isocyanate derivative (A2)) in the polyisocyanate composition (X) is 30% by mass or more. This makes it possible to create an adhesive with excellent adhesion to metal substrates such as aluminum foil and aluminum vapor-deposited films.

[0030] (Acid anhydride (B)) Examples of acid anhydrides (B) include cyclic aliphatic acid anhydrides, aromatic acid anhydrides, and unsaturated carboxylic acid anhydrides, and one or more can be used in combination. More specifically, examples include maleic anhydride, phthalic anhydride, trimellitic anhydride, pyromellitic anhydride, benzophenonetetracarboxylic anhydride, dodecenylsuccinic anhydride, polyadipic anhydride, polyazelaic anhydride, polysebacic anhydride, poly(ethyloctadecanediic acid) anhydride, poly(phenylhexadecanedioic acid) anhydride, tetrahydrophthalic anhydride, methyltetrahydrophthalic anhydride, methylhexahydrophthalic anhydride, hexahydrophthalic anhydride, methylhymic anhydride, and trialkyltetrahydrophthalic acid Examples include anhydrides, methylcyclohexenedicarboxylic acid anhydride, methylcyclohexenetetracarboxylic acid anhydride, ethylene glycol bistrimellitate dianhydride, hetic acid anhydride, nadic acid anhydride, methylnadic acid anhydride, 5-(2,5-dioxotetrahydro-3-furanyl)-3-methyl-3-cyclohexane-1,2-dicarboxylic acid anhydride, 3,4-dicarboxy-1,2,3,4-tetrahydro-1-naphthalenesuccinic acid dianhydride, 1-methyl-dicarboxy-1,2,3,4-tetrahydro-1-naphthalenesuccinic acid dianhydride, etc.

[0031] As the acid anhydride (B), the above-mentioned compound modified with glycol may be used. Examples of glycols that can be used for modification include alkylene glycols such as ethylene glycol, propylene glycol, and neopentyl glycol; and polyether glycols such as polyethylene glycol, polypropylene glycol, and butyltetramethylene ether glycol. Furthermore, copolymer polyether glycols of two or more of these glycols and / or polyether glycols can also be used.

[0032] Alternatively, as the acid anhydride (B), a homopolymer or copolymer of a compound having a polymerizable unsaturated group, such as maleic anhydride, from among the compounds mentioned above may be used. Compounds that can copolymerize with a compound having an acid anhydride group and a polymerizable unsaturated group include α-olefins such as ethylene, propylene, 1,3-butadiene, and cyclopentylethylene; vinyl compounds having an aromatic ring such as styrene, 1-ethynyl-4-methylbenzene, divinylbenzene, 1-ethynyl-4-methylethylbenzene, benzonitrile, acrylonitrile, p-tert-butylstyrene, 4-vinylbiphenyl, 4-ethynylbenzyl alcohol, 2-ethynylnaphthalene, and phenanthrene-9-ethynyl; and fluoroolefins such as vinylidene fluoride, tetrafluoroethylene, hexafluoropropylene, and chlorotrifluoroethylene. These can be used individually or in combination of two or more. It is preferable to use styrene and p-tert-butylstyrene, which are vinyl compounds having an aromatic ring.

[0033] The acid anhydride (B) used in the present invention is more preferably a non-aromatic carboxylic acid anhydride. This makes it possible to suppress the decrease in adhesive strength even after retort treatment without significantly impairing productivity in the process of dissolving the acid anhydride. In this specification, non-aromatic carboxylic acid anhydrides refer to those in which the anhydride ring is not directly bonded to the aromatic ring, i.e., cyclic aliphatic acid anhydrides, unsaturated carboxylic acid anhydrides, glycol-modified versions of these acid anhydrides, copolymers with compounds having polymerizable unsaturated groups, etc.

[0034] Acid anhydride (B) is used in a range where the acid value derived from acid anhydride (B) in the polyisocyanate composition (X) is between 1 mg KOH / g and 100 mg KOH / g, and more preferably in a range between 5 mg KOH / g and 70 mg KOH / g. The acid value derived from acid anhydride (B) may be calculated from the structure and amount of added acid anhydride (B) to determine the acid value when the anhydride ring opens, or it may be measured using FT-IR.

[0035] When measuring using FT-IR, the value is calculated using the following formula, with the coefficient (f) obtained from the calibration curve prepared with a chloroform solution of acid anhydride (B), the absorbance (I) of the stretching peak of the anhydride ring of acid anhydride (B) in the polyisocyanate composition (X), and the absorbance (II) of the stretching peak of the carbonyl group when the anhydride ring of acid anhydride (B) opens. Unless otherwise specified, the unit is mgKOH / g. In the following formula, the molecular weight of potassium hydroxide is assumed to be 56.11.

[0036]

number

[0037] The polyisocyanate composition (X) used in the present invention has a content of 0.1% by mass or less of diisocyanate monomers with a molecular weight of 280 or less, i.e., diisocyanate monomers such as aromatic diisocyanates, aromatic aliphatic diisocyanates, aliphatic diisocyanates, and alicyclic diisocyanates, which are exemplified as raw materials for polyurethane polyisocyanate (A1).

[0038] The diisocyanate monomer content can be measured by gas chromatography using an internal standard, for example, according to ASTM D 3432. Alternatively, it can be measured by liquid chromatography under the following conditions.

[0039] Equipment: Waters Corporation "ACQUITY UPLC H-Class" Data processing: Empower-3 manufactured by Waters Corporation Column: Waters Corporation "ACQUITY UPLC HSS T3" (100 mm × 2.1 mmφ, 1.8 μm) 40℃ Eluent: Ammonium formate aqueous solution / methanol, 0.3 mL / min Detector: PDA Sample preparation: 1. Dissolve 100 mg of appropriately blocked sample in 10 ml of THF (for LC). 2. Vortex for 30 seconds. 3. Dilute as appropriate with the eluent (mobile phase). The solution was passed through a 4.0.2 μm filtration filter to obtain the measurement sample. Calculation of area ratio: Calculated using the maximum absorption wavelength for the target material.

[0040] The content of diisocyanate monomer can be adjusted, for example, by removing the diisocyanate monomer from a composition containing diisocyanate monomer using a short-pass distillation apparatus or a thin-film distillation apparatus.

[0041] The polyisocyanate composition (X) is prepared by adding an acid anhydride (B) when synthesizing polyurethane polyisocyanate (A1) to obtain a composition containing polyurethane polyisocyanate (A1) and acid anhydride (B), and then removing the diisocyanate monomer using a short-pass distillation apparatus or thin-film distillation apparatus; by heating the polyurethane polyisocyanate (A1) and acid anhydride (B) from which the diisocyanate monomer has been removed to approximately 50°C to 150°C; or by removing the diisocyanate monomer from a composition containing polyurethane polyisocyanate (A1), diisocyanate monomer, and acid anhydride (B) using a short-pass distillation apparatus or thin-film distillation apparatus. In any of the preparation methods, compounds other than polyurethane polyisocyanate (A1) and acid anhydride (B) may be present in the system as long as they do not impair the effects of the present invention. Examples of such compounds include isocyanate derivatives (A2).

[0042] Acid anhydride (B) has been used as an additive in solvent-type two-component curing adhesives, but most of them are solid at room temperature. Therefore, simply adding it to solvent-free adhesives does not allow it to exert its full effect. In the manufacturing process of polyurethane polyisocyanate, which is widely used as the isocyanate component in solvent-free two-component curing adhesives, adding acid anhydride (B) to the diisocyanate monomer and dissolving the acid anhydride (B) by heating reduces the decrease in strength after retort treatment, but it does not maintain the performance when the bag material is stored for a long period after retort treatment. In the present invention, by using polyurethane polyisocyanate (A1) and acid anhydride (B) in combination, and by reducing the content of diisocyanate monomer in the polyisocyanate composition (X) as much as possible, these problems are resolved, and an adhesive can be provided that has excellent adhesion to metal substrates and metal vapor-deposited layers, and excellent resistance to acids and oils to the contents, even after the bag material is stored for a certain period after retort treatment.

[0043] The viscosity of the polyisocyanate composition (X) is adjusted to a range suitable for the non-solvent lamination method. For example, the viscosity at 40°C is adjusted to be in the range of 100 to 20,000 mPas, more preferably 500 to 10,000 mPas. The viscosity of the polyisocyanate composition (X) can be adjusted, for example, by the structure of the polyurethane polyisocyanate (A) (the polyol used). The viscosity of the polyisocyanate composition (X) is measured, for example, using a rotational viscometer with a cone-plate: 1° × diameter 50 mm, shear rate: 100 sec. -1 It can be measured at 40℃±1℃.

[0044] (Polyol composition (Y)) (Polyol(C)) The polyol composition (Y) contains a polyol (C). Examples of such polyols include polyester polyols (C1), polyether polyols (C2), vegetable oil polyols (C3), polyurethane polyols (C4), sugar alcohols (C5), etc., and can be used individually or in combination of two or more.

[0045] Examples of polyester polyols (C1) include polyester polyols obtained as reaction products of polyhydric alcohols and polycarboxylic acids, and lactone-based polyester polyols obtained by polycondensation reactions of aliphatic polyols with various lactones such as ε-caprolactone. It is preferable to use polyester polyols obtained as reaction products of polyhydric alcohols and polycarboxylic acids. As polyhydric alcohols and polycarboxylic acids, those similar to those exemplified as raw materials for polyuret polyisocyanate (A1) can be used individually or in combination.

[0046] The polycarboxylic acid used as a raw material for polyester polyol (C1) preferably contains an aromatic polycarboxylic acid. The amount of aromatic polycarboxylic acid in the polycarboxylic acid can be adjusted as appropriate depending on the purpose, but as an example, it is 20% by mass or more. The entire amount of polycarboxylic acid may also be aromatic polycarboxylic acid.

[0047] The molecular weight of the polyester polyol (C1) is preferably 300 g / mol or more and 5000 g / mol or less, and more preferably 400 g / mol or more and 3000 g / mol or less. The hydroxyl value of the polyester polyol (C1) is preferably 20 mg KOH / g or more and 400 mg KOH / g or less.

[0048] Examples of polyether polyols (C2) include glycols such as ethylene glycol, propylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 3-methyl-1,5-pentanediol, 1,6-hexanediol, neopentyl glycol, methylpentanediol, dimethylbutanediol, butylethylpropanediol, diethylene glycol, triethylene glycol, tetraethylene glycol, dipropylene glycol, tripropylene glycol, bishydroxyethoxybenzene, 1,4-cyclohexanediol, 1,4-cyclohexanedimethanol, and triethylene glycol; and alkylene oxides such as ethylene oxide, propylene oxide, butylene oxide, styrene oxide, epichlorohydrin, tetrahydrofuran, and cyclohexylene, obtained by addition polymerization of alkylene oxides such as ethylene oxide, propylene oxide, butylene oxide, styrene oxide, epichlorohydrin, tetrahydrofuran, and cyclohexylene in the presence of polymerization initiators such as glycols such as ethylene glycol, propylene glycol, pentaerythritol, and triols of polypropylene glycol. Polypropylene polyols are preferred.

[0049] The molecular weight of the polyether polyol (C2) can be adjusted as appropriate, but as an example, it is preferably 300 g / mol or more and 5000 g / mol or less. The hydroxyl value of the polyether polyol (C2) can be adjusted as appropriate, but as an example, it is preferably between 20 mg KOH / g and 500 mg KOH / g.

[0050] Examples of vegetable oil polyols (C3) include castor oil, dehydrated castor oil, hydrogenated castor oil (a hydrogenated product of castor oil), and castor oil alkylene oxide adducts of 5 to 50 moles.

[0051] Polyurethane polyols (C4) are reaction products of low-molecular-weight or high-molecular-weight polyols and polyisocyanate compounds. The low-molecular-weight or high-molecular-weight polyols can be the same as those used for polyhydric alcohols (n). The polyisocyanate compounds can be the same as those used for polyisocyanates (l).

[0052] Examples of sugar alcohols (C5) include pentaerythritol, sucrose, xylitol, sorbitol, isomalt, lactitol, maltitol, and mannitol sugars.

[0053] The polyol (C) preferably contains at least one selected from polyester polyol (C1) and polyether polyol (C2), and more preferably contains polyester polyol (C1). When polyol (C) contains polyester polyol (C1), its content can be adjusted as appropriate, but as an example, it is preferably 20% by mass or more of polyol (C), and more preferably 30% by mass or more. The entire amount of polyol (C) may be polyester polyol (C1).

[0054] (Amine compound (D)) The polyol composition (Y) may contain an amine compound (D) having an amino group. In this specification, an amino group refers to an NH2 group or an NHR group (where R is an alkyl group or aryl group which may have a functional group).

[0055] As the amine compound (D), any known compound can be used without particular limitation, including methylenediamine, ethylenediamine, isophoronediamine, 3,9-dipropanamine-2,4,8,10-tetraoxaspirodoundecane, lysine, 2,2,4-trimethylhexamethylenediamine, hydrazine, piperazine, 2-hydroxyethylethylenediamine, di-2-hydroxyethylethylenediamine, di-2-hydroxyethylpropylenediamine, 2-hydroxypropylethylenediamine, di-2-hydroxypropylethylenediamine, poly(propylene glycol)diamine, poly(propylene glycol)triamine, poly(propylene glycol)tetraamine, 1,2-diaminopropane, 1,3-diaminopropane,

[0056] 1,4-diaminobutane, 1,5-diaminopentane, 1,6-diaminohexane, 1,7-diaminoheptane, 1,8-diaminooctane, 1,9-diaminononane, 1,10-diaminodecane, diethylenetriamine, dipropylenetriamine, triethylenetetramine, tripylenetetramine, tetraethylenepentamine, tetrapropylenepentamine, pentaethylenehexamine, nonaethylenedecamine, trimethylhexamethylenediamine, tetra(aminomethyl)methane, tetrakis(2-aminoethylaminomethyl)methane, 1,3-bis(2'-aminoethylamino)propane, triethylene-bis(trimethylene)hexamine, bis(3-aminoethyl)amine, bishexamethylenetriamine, 1,4-cyclohexanediamine, 4,4'-methylenebiscyclohexylamine, 4,4'-isopropylidenebiscyclohexylamine, norbornadiamine,

[0057] Amine compounds having multiple amino groups (D1), such as bis(aminomethyl)cyclohexane, diaminodicyclohexylmethane, isophoronediamine, mensendiamine, bis(cyanoethyl)diethylenetriamine, 1,4-bis-(8-aminopropyl)-piperazine, piperazine-1,4-diazacycloheptane, 1-(2'-aminoethylpiperazine), 1-[2'-(2"-aminoethylamino)ethyl]piperazine, tricyclodecanediamine, and polyureamines which are reaction products of the above-mentioned polyamines and the above-mentioned isocyanate components.

[0058] Primary or secondary alkanolamines (D2) such as monoethanolamine, monoisopropanolamine, monobutanolamine, N-methylethanolamine, N-ethylethanolamine, N-methylpropanolamine, diethanolamine, and diisopropanolamine,

[0059] Examples include primary or secondary amines (D3) such as ethylamine, octylamine, laurylamine, myristylamine, stearylamine, oleylamine, diethylamine, dibutylamine, and distearylamine.

[0060] The amount of amine compound (D) is preferably blended such that the amine value of the polyol composition (Y) is 20 to 100 mg KOH / g, more preferably 25 to 70 mg KOH / g.

[0061] In this specification, the amine value refers to the number of milligrams of KOH equivalent to the amount of HCl required to neutralize 1 g of the sample. There are no particular restrictions, and it can be calculated using known methods. If the chemical structure of amine compound (D) and, if necessary, the average molecular weight are known, it can be calculated using the formula: (number of amino groups per molecule / average molecular weight) × 56.1 × 1000. If the chemical structure or average molecular weight of the amine compound is unknown, it can be measured according to known amine value measurement methods, such as JIS K7237-1995.

[0062] (Monool compound (E)) The polyol composition (Y) may contain a monool compound (E) having one alcoholic hydroxyl group. The main chain of the monool compound (E) is not particularly limited and can be vinyl resins, acrylic resins, polyesters, epoxy resins, urethane resins, etc., having one hydroxyl group. Aliphatic alcohols, alkylalkylene glycols, etc., can also be used. The main chain of the monool compound (E) may be linear or branched. There are no particular limitations on the bonding position of the hydroxyl group, but it is preferable that it be located at the end of the molecular chain.

[0063] Specific examples of monool compounds (E) include methanol, ethanol, propanol, butanol, pentanol, hexanol, heptanol, octanol, nonanol, decanol, lauryl alcohol, myristyl alcohol, pentadecanol, cetyl alcohol, heptadecanol, stearyl alcohol, nonadecanol, other alkanols (C20-C50), oleyl alcohol, and aliphatic monools such as their isomers.

[0064] Cyclohexanol, methylcyclohexanol, 4-butylcyclohexanol, 4-pentylcyclohexanol, 4-hexylcyclohexanol, cyclodecanol, cyclododecanol, cyclopentadecanol, 4-isopropylcyclohexanol, 3,5,5-trimethylcyclohexanol, menthol, 2-norbornanol, borneol, 2-adamantanol, dicyclohexylmethanol, decatol, 2-cyclohexylcyclohexanol, 4-cyclohexylcyclohexanol, 4-(4-propylcyclohexyl)cyclohexanol, 4-(4-pentylcyclohex Sil-cyclohexanol, α-ambrinol, deoxycorticosterone, 11-dehydrocorticosterone, cholesterol, β-sitosterol, campesterol, stigmasterol, brassicasterol, lanosterol, ergosterol, β-cholestanol, testosterone, estrone, digitoxygenin, dehydroepiandrosterone, coprostanol, pregnenolone, epicholestanol, 7-dehydrocholesterol, estradiol benzoate, tigogenin, hecogenin, methandienone, cortisone acetate, stenolone, and alicyclic monools such as their isomers.

[0065] Aromatic aliphatic monools such as benzyl alcohol,

[0066] Examples include polyoxyalkylene monools obtained by ring-opening addition polymerization of alkylene oxides such as ethylene oxide, propylene oxide, butylene oxide, and tetrahydrofuran, using an alkyl compound containing one active hydrogen atom as an initiator.

[0067] The viscosity of the polyol composition (Y) is adjusted to a range suitable for the non-solvent lamination method. For example, the viscosity at 40°C is adjusted to be in the range of 100 to 50,000 mPas, more preferably 100 to 30,000 mPas. The viscosity of the polyol composition (Y) can be adjusted by the polyol (C) skeleton or by plasticizers, as described later. For example, when adjusting with a polyester polyol (C1) skeleton, the viscosity can be reduced by using a polyester polyol obtained by the reaction of an aliphatic carboxylic acid with a polyol. Alternatively, the viscosity can be increased by using a polyester polyol (C1) obtained by the reaction of an aromatic carboxylic acid with a polyol.

[0068] (Other components of the adhesive) The two-component curing adhesive of the present invention may contain components other than those described above. These other components may be included in either or both of the polyisocyanate composition (X) and the polyol composition (Y), or they may be prepared separately and mixed with the polyisocyanate composition (X) and polyol composition (Y) immediately before application of the adhesive. Each component will be described below.

[0069] (catalyst) Examples of catalysts include metal catalysts, amine catalysts, aliphatic cyclic amide compounds, and quaternary ammonium salts.

[0070] Examples of metal catalysts include metal complex catalysts, inorganic metal catalysts, and organometallic catalysts. Examples of metal complex catalysts include acetylacetonate salts of metals selected from the group consisting of Fe (iron), Mn (manganese), Cu (copper), Zr (zirconium), Th (thorium), Ti (titanium), Al (aluminum), and Co (cobalt), such as iron acetylacetonate, manganese acetylacetonate, copper acetylacetonate, and zirconia acetylacetonate.

[0071] Examples of inorganic metal catalysts include those selected from Sn, Fe, Mn, Cu, Zr, Th, Ti, Al, Co, and the like.

[0072] Examples of organometallic catalysts include organozinc compounds such as zinc octoate, zinc neodecanoate, and zinc naphthenate; organotin compounds such as stanus diacetate, stanus dioctoate, stanus dioleate, stanus dilaurate, dibutyltin diacetate, dibutyltin dilaurate, dioctyltin dilaurate, dibutyltin oxide, and dibutyltin dichloride; organonickel compounds such as nickel octoate and nickel naphthenate; organocobalt compounds such as cobalt octoate and cobalt naphthenate; organobismuth compounds such as bismuth octoate, bismuth neodecanoate, and bismuth naphthenate; tetraisopropyloxytitanate, dibutyltitanium dichloride, tetrabutyltitanium trichloride, butoxytitanium trichloride; aliphatic diketones; aromatic diketones; and titanium compounds such as titanium chelate complexes with at least one alcohol having 2 to 10 carbon atoms as a ligand.

[0073] Amine-based catalysts include triethylenediamine, 2-methyltriethylenediamine, quinuclidine, 2-methylquinuclidine, N,N,N',N'-tetramethylethylenediamine, N,N,N',N'-tetramethylpropylenediamine, N,N,N',N",N"-pentamethyldiethylenetriamine, N,N,N',N",N"-pentamethyl-(3-aminopropyl)ethylenediamine, N,N,N',N",N"-pentamethyldipropylenetriamine, N,N,N',N'-tetramethylhexamethylenediamine, bis(2-dimethylaminoethyl) ether, dimethylethanolamine, dimethylisopropanolamine, dimethylaminoethoxyethanol, N,N-dimethyl-N'-(2-hydroxyethyl)ethylenediamine, N,N-dimethyl-N'-(2-hydroxyethyl)propanediamine, bis(dimethylaminopropyl)amine, bis(dimethylaminopropyl)isopropanediamine Lopanolamine, 3-Quinuclidinol, N,N,N',N'-Tetramethylguanidine, 1,3,5-Tris(N,N-dimethylaminopropyl)hexahydro-S-triazine, 1,8-Diazabicyclo[5.4.0]undecene-7, N-Methyl-N'-(2-dimethylaminoethyl)piperazine, N,N'-Dimethylpiperazine, Dimethylcyclohexylamine, N-Methylmorpholine, N-Ethylmorpholine, 1-Methylimidazole, 1 Examples include 2-dimethylimidazole, 1-isobutyl-2-methylimidazole, 1-dimethylaminopropylimidazole, N,N-dimethylhexanolamine, N-methyl-N'-(2-hydroxyethyl)piperazine, 1-(2-hydroxyethyl)imidazole, 1-(2-hydroxypropyl)imidazole, 1-(2-hydroxyethyl)-2-methylimidazole, and 1-(2-hydroxypropyl)-2-methylimidazole.

[0074] Examples of aliphatic cyclic amide compounds include δ-valerolactam, ε-caprolactam, ω-enanthollactam, η-capryllactam, and β-propiolactam. Among these, ε-caprolactam is most effective in promoting curing.

[0075] Examples of quaternary ammonium salts include alkylammonium, aromatic ammonium, hydroxy salts, alkylates, and halide salts. Examples include, but are not limited to, tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetrapropylammonium hydroxide, tetrabutylammonium hydroxide, benzyltrimethylammonium hydroxide, tetrabutylammonium fluoride, tetrabutylammonium chloride, tetrabutylammonium bromide, tetrabutylammonium iodide, benzyltriethylammonium chloride, and hexadecyltrimethylammonium bromide.

[0076] (Coupling agent) Examples of coupling agents include silane coupling agents, titanate-based coupling agents, and aluminum-based coupling agents.

[0077] Examples of silane coupling agents include aminosilanes such as γ-aminopropyltriethoxysilane, γ-aminopropyltrimethoxysilane, N-β(aminoethyl)-γ-aminopropyltrimethoxysilane, N-β(aminoethyl)-γ-aminopropyltrimethyldimethoxysilane, N-phenyl-γ-aminopropyltrimethoxysilane, bis[3-(trimethoxysilyl)propyl]amine, and bis[3-(triethoxysilyl)propyl]amine; epoxysilanes such as β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, and γ-glycidoxypropyltriethoxysilane; vinylsilanes such as vinyltris(β-methoxyethoxy)silane, vinyltriethoxysilane, vinyltrimethoxysilane, and γ-methacryloxypropyltrimethoxysilane; and hexamethyldisilazane and γ-mercaptopropyltrimethoxysilane.

[0078] Examples of titanate-based coupling agents include tetraisopropoxytitanium, tetra-n-butoxytitanium, butyl titanate dimer, tetrastearyl titanate, titanium acetylacetonate, titanium lactate, tetraoctylene glycol titanate, titanium lactate, and tetrastearoxititanium.

[0079] Examples of aluminum-based coupling agents include acetalkoxyaluminum diisopropylate.

[0080] (Pigment) There are no particular restrictions on the pigments used, and examples include organic and inorganic pigments such as extender pigments, white pigments, black pigments, gray pigments, red pigments, brown pigments, green pigments, blue pigments, metal powder pigments, luminescent pigments, pearlescent pigments, and even plastic pigments, as listed in the 1970 edition of the Paint Raw Materials Handbook (compiled by the Japan Paint Manufacturers Association).

[0081] Examples of extender pigments include precipitated barium sulfate, granite, precipitated calcium carbonate, calcium bicarbonate, limestone, alumina white, silica, hydrated fine silica (white carbon), ultrafine anhydrous silica (aerosil), silica sand, talc, precipitated magnesium carbonate, bentonite, clay, kaolin, and yellow ochre.

[0082] Specific examples of organic pigments include various insoluble azo pigments such as Benzidine Yellow, Hansa Yellow, and Laked 4R; soluble azo pigments such as Laked C, Carmine 6B, and Bordeaux 10; various (copper) phthalocyanine pigments such as phthalocyanine blue and phthalocyanine green; various chlorinated dye lakes such as rhodamine lake and methyl violet lake; various mordant dyes such as quinoline lake and fast sky blue; various vat dyes such as anthraquinone pigments, thioindigo pigments, and perinone pigments; various quinacridone pigments such as Syncasia Red B; various dioxazine pigments such as dioxazine violet; various condensed azo pigments such as chromophthal; and aniline black.

[0083] Inorganic pigments include various chromates such as lead yellow, zinc chromate, and molybdate orange; various ferrocyanide compounds such as Prussian blue; various metal oxides such as titanium dioxide, zinc oxide, mapo yellow, iron oxide, red iron oxide, chrome green oxide, and zirconium oxide; various sulfides or selenides such as cadmium yellow, cadmium red, and mercury sulfide; various sulfates such as barium sulfate and lead sulfate; various silicates such as calcium silicate and ultramarine; various carbonates such as calcium carbonate and magnesium carbonate; various phosphates such as cobalt violet and manganese purple; various metal powder pigments such as aluminum powder, gold powder, silver powder, copper powder, bronze powder, and brass powder; metal flake pigments and mica flake pigments; metallic pigments and pearl pigments such as mica flake pigments coated with metal oxides and mica-like iron oxide pigments; graphite, carbon black, etc.

[0084] Examples of plastic pigments include "Grandeur PP-1000" and "PP-2000S" manufactured by DIC Corporation.

[0085] The pigments used can be selected appropriately depending on the purpose, but for example, inorganic oxides such as titanium dioxide and zinc oxide are preferred as white pigments because they have excellent durability, weather resistance, and design properties, and carbon black is preferred as a black pigment.

[0086] The amount of pigment added is, for example, 1 to 400 parts by mass per 100 parts by mass of the total non-volatile content of the polyisocyanate composition (X) and the polyol composition (Y), and is more preferably 10 to 300 parts by mass to improve adhesion and blocking resistance.

[0087] (Plasticizer) Examples of plasticizers include phthalate-based plasticizers, fatty acid-based plasticizers, aromatic polycarboxylic acid-based plasticizers, phosphate-based plasticizers, polyol-based plasticizers, epoxy-based plasticizers, polyester-based plasticizers, and carbonate-based plasticizers.

[0088] Examples of phthalate-based plasticizers include phthalate ester plasticizers such as dimethyl phthalate, diethyl phthalate, dibutyl phthalate, diisobutyl phthalate, dihexyl phthalate, diheptyl phthalate, di-(2-ethylhexyl) phthalate, di-n-octyl phthalate, dinonyl phthalate, diisononyl phthalate, didecyl phthalate, diisodecyl phthalate, ditridecyl phthalate, diundecyl phthalate, dilauryl phthalate, distearyl phthalate, diphenyl phthalate, dibenzyl phthalate, butylbenzyl phthalate, dicyclohexyl phthalate, octyldecyl phthalate, dimethyl isophthalate, di-(2-ethylhexyl) isophthalate, and diisooctyl isophthalate, as well as tetrahydrophthalate ester plasticizers such as di-(2-ethylhexyl)tetrahydrophthalate, di-n-octyltetrahydrophthalate, and diisodecyltetrahydrophthalate.

[0089] Examples of fatty acid-based plasticizers include adipic acid-based plasticizers such as di-n-butyl adipate, di-(2-ethylhexyl) adipate, diisodecyl adipate, diisononyl adipate, di(C6-C10 alkyl) adipate, and dibutyldiglycol adipate; azelaic acid-based plasticizers such as di-n-hexyl azelate, di-(2-ethylhexyl) azelate, and diisooctyl azelate; and di-n-butyl sebacate, di-(2 Sebacate-based plasticizers such as -ethylhexyl) sebacate and diisononyl sebacate; maleic acid-based plasticizers such as dimethyl maleate, diethyl maleate, di-n-butyl maleate, and di-(2-ethylhexyl) maleate; fumaric acid-based plasticizers such as di-n-butyl fumarate and di-(2-ethylhexyl) fumarate; monomethyl itaconate, monobutyl itaconate, dimethyl itaconate, diethyl itaconate, dibutyrate Examples of plasticizers include itaconic acid-based plasticizers such as ruitaconate and di-(2-ethylhexyl)itaconate; stearic acid-based plasticizers such as n-butyl stearate, glycerin monostearate, and diethylene glycol distearate; oleic acid-based plasticizers such as butyl oleate, glyceryl monooleate, and diethylene glycol monooleate; citrate-based plasticizers such as triethyl citrate, tri-n-butyl citrate, acetyl triethyl citrate, acetyl tributyl citrate, and acetyl tri-(2-ethylhexyl) citrate; ricinoleic acid-based plasticizers such as methylacetyl ricinoleate, butylacetyl ricinoleate, glyceryl monoricinoleate, and diethylene glycol monoricinoleate; and other fatty acid-based plasticizers such as diethylene glycol monolaurate, diethylene glycol diperargonate, and pentaerythritol fatty acid esters.

[0090] Examples of aromatic polycarboxylic acid plasticizers include trimellitic acid plasticizers such as tri-n-hexyl trimellitate, tri-(2-ethylhexyl) trimellitate, tri-n-octyl trimellitate, triisooctyl trimellitate, triisononyl trimellitate, tridecyl trimellitate, and triisodecyl trimellitate, as well as pyromellitic acid plasticizers such as tetra-(2-ethylhexyl) pyromelitate and tetra-n-octyl pyromelitate.

[0091] Examples of phosphate-based plasticizers include triethyl phosphate, tributyl phosphate, tri-(2-ethylhexyl) phosphate, tributoxyethyl phosphate, triphenyl phosphate, octyldiphenyl phosphate, cresyldiphenyl phosphate, cresylphenyl phosphate, tricresyl phosphate, trixylenyl phosphate, tris(chloroethyl) phosphate, tris(chloropropyl) phosphate, tris(dichloropropyl) phosphate, and tris(isopropylphenyl) phosphate.

[0092] Examples of polyol-based plasticizers include glycol-based plasticizers such as diethylene glycol dibenzoate, dipropylene glycol dibenzoate, triethylene glycol dibenzoate, triethylene glycol di-(2-ethyl butyrate), triethylene glycol di-(2-ethylhexoate), and dibutylmethylene bisthioglycolate, as well as glycerin-based plasticizers such as glycerol monoacetate, glycerol triacetate, and glycerol tributyrate.

[0093] Examples of epoxy plasticizers include epoxidized soybean oil, epoxybutyl stearate, di-2-ethylhexyl epoxyhexahydrophthalate, diisodecyl epoxyhexahydrophthalate, epoxy triglycerides, octyl epoxidized oleate, and decyl epoxidized oleate.

[0094] Examples of polyester-based plasticizers include adipic acid-based polyesters, sebaciate-based polyesters, and phthalate-based polyesters.

[0095] Examples of carbonate-based plasticizers include propylene carbonate and ethylene carbonate.

[0096] Other plasticizers include partially hydrogenated terphenyl, adhesive plasticizers, and polymerizable plasticizers such as diallyl phthalate, acrylic monomers, and oligomers. These plasticizers can be used individually or in combination of two or more.

[0097] (Phosphate compounds) Examples of phosphate compounds include phosphoric acid, pyrophosphate, triphosphate, methyl acid phosphate, ethyl acid phosphate, butyl acid phosphate, dibutyl phosphate, 2-ethylhexyl acid phosphate, bis(2-ethylhexyl) phosphate, isododecyl acid phosphate, butoxyethyl acid phosphate, oleyl acid phosphate, tetracosyl acid phosphate, 2-hydroxyethyl methacrylate acid phosphate, and polyoxyethylene alkyl ether phosphate.

[0098] (Form of adhesive) The two-component curing adhesive of the present invention is used in a solvent-free form. In this specification, a "solvent-free" adhesive refers to an adhesive in which the polyisocyanate composition (X) and polyol composition (Y) substantially do not contain esters such as ethyl acetate, butyl acetate, and cellosolve acetate, ketones such as acetone, methyl ethyl ketone, isobutyl ketone, and cyclohexanone, ethers such as tetrahydrofuran and dioxane, aromatic hydrocarbons such as toluene and xylene, halogenated hydrocarbons such as methylene chloride and ethylene chloride, and highly soluble organic solvents such as dimethyl sulfoxide and dimethyl sulfamide, particularly ethyl acetate or methyl ethyl ketone, and is used in a method of bonding with another substrate without going through a step of heating in an oven or the like to volatilize the solvent after coating the substrate, so-called non-solvent laminating method. If trace amounts of organic solvent remain in a polyisocyanate composition (X) or polyol composition (Y) due to incomplete removal of components or organic solvents used as reaction media during the manufacturing of their raw materials, it is considered that the composition is substantially free of organic solvents. Furthermore, if the polyol composition (Y) contains low molecular weight alcohol, the low molecular weight alcohol reacts with the polyisocyanate composition (X) to become part of the coating film, and therefore does not need to be volatilized after coating. Consequently, this form is also treated as a solvent-free adhesive, and the low molecular weight alcohol is not considered an organic solvent.

[0099] The two-component curing adhesive of the present invention is preferably formulated so that the ratio [NCO] / [OH] of the number of moles of isocyanate groups [NCO] contained in the polyisocyanate composition (X) to the number of moles of hydroxyl groups [OH] contained in the polyol composition (Y) is between 1.0 and 5.0. This makes it possible to obtain appropriate curing properties regardless of the ambient humidity during coating.

[0100] <Other uses> The polyisocyanate composition (X) described above is suitable as a solvent-free, two-component curing adhesive for bonding a plastic film to a substrate having a metal foil such as aluminum foil or a metal vapor-deposited layer such as aluminum, but it can also be used for other applications. For example, it can be used as a two-component curing coating agent in combination with a composition containing a compound that is reactive with isocyanate groups (isocyanate reactive composition). Such a coating agent exhibits excellent adhesion to metal substrates such as steel plates.

[0101] The compounds that react with isocyanate groups are not particularly limited and can be those that are conventionally known. Examples include polyols such as polyester polyols, polyether polyols, polycarbonate polyols, and acrylic polyols; compounds having epoxy groups such as bisphenol A type epoxy resins; compounds having primary or secondary amino groups; polyolefins modified with compounds having acidic groups and polymerizable unsaturated groups such as maleic anhydride and (meth)acrylic acid; and compounds having acidic groups such as copolymers of compounds having acidic groups and polymerizable unsaturated groups with compounds having unsaturated double bonds. One or more of these can be used in combination.

[0102] <Laminate> The laminate of the present invention can be obtained, for example, by a method having a two-component mixing step in which a polyisocyanate composition (X) and a polyol composition (Y) are mixed in advance, applied to a first substrate, then laminated onto the coated surface with a second substrate, and the adhesive layer is cured; or by a method having a two-component fractional coating step in which the polyisocyanate composition (X) and the polyol composition (Y) are applied separately to the first and second substrates, respectively, and then the first and second substrates are laminated by bringing the respective coated surfaces into contact and pressing them together, and the adhesive layer is cured. There are no particular restrictions on the film used, and a film can be appropriately selected according to the application.

[0103] For example, for food packaging, examples include 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), ethylene vinyl alcohol copolymer, and gas barrier heat-seal films such as polyolefin films, polyvinyl alcohol films, and ethylene-vinyl alcohol copolymer films, which have an olefin-based heat-sealable resin layer on one or both sides of a gas barrier resin such as polyvinyl alcohol.

[0104] Furthermore, it is also preferable to use biomass films, biodegradable films, or recycled plastic films formed from materials containing biomass-derived components, biodegradable components, or recycled components. Biomass films, biodegradable films, and recycled plastic films are sold by various companies. In addition, films certified in each country can be used, such as film sheets listed in the biomass certified product list of the Japan Organic Resources Association, films listed in the Eco Mark certified product list of the Japan Environment Association, and films bearing the symbol mark set by the Japan Bioplastics Association.

[0105] (Biomass film) A well-known example of a biomass film is one that uses biomass-derived ethylene glycol as a raw material. Biomass-derived ethylene glycol is made from ethanol (biomass ethanol) produced from biomass. For example, biomass-derived ethylene glycol can be obtained by conventionally known methods, such as a method that produces ethylene glycol via ethylene oxide from biomass ethanol. Alternatively, commercially available biomass ethylene glycol may be used; for example, the biomass ethylene glycol commercially available from India Glycol can be suitably used.

[0106] For example, as an alternative to conventional polyethylene terephthalate films using petroleum-based raw materials, films containing biomass polyesters, biomass polyethylene terephthalate, etc., which use biomass-derived ethylene glycol as the diol unit and fossil fuel-derived dicarboxylic acid as the dicarboxylic acid unit are known.

[0107] The dicarboxylic acid units in biomass polyesters use dicarboxylic acids derived from fossil fuels. Aromatic dicarboxylic acids, aliphatic dicarboxylic acids, and their derivatives can be used without restriction as dicarboxylic acids. Furthermore, in addition to the diol and dicarboxylic acid components mentioned above, a copolymerized polyester may also be obtained by adding a copolymerizing component as a third component, such as a bifunctional oxycarboxylic acid or at least one polyfunctional compound selected from the group consisting of trifunctional or more polyhydric alcohols, trifunctional or more polyhydric acids and / or their anhydrides, and trifunctional or more oxycarboxylic acids, in order to form a crosslinked structure.

[0108] Furthermore, 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, which contain polyethylene resins made from biomass-derived ethylene glycol, are also known. The polyethylene resin is not particularly limited except for the use of biomass-derived ethylene glycol as part of the raw materials. Examples 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). These can be used individually or in combination of two or more types.

[0109] The α-olefin constituting the copolymer of ethylene and α-olefin is not particularly limited, and examples 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. Among these, 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 even less likely for damage such as punctures or tears to occur when the films rub against each other, and has a density of 0.910 to 0.925 g / cm³. 3 A linear low-density polyethylene resin is more preferable.

[0110] Biomass films are also available that use biomass raw materials classified by the biomass plasticity level specified in ISO 16620 or ASTM D6866. Radioactive carbon-14C exists in the atmosphere at a rate of 1 in 10¹² atoms, and this rate does not change even in atmospheric carbon dioxide. Therefore, this rate does not change in plants that fix carbon dioxide through photosynthesis. For this reason, 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 proportion of plant-derived resin in the resin, i.e., the biomass plasticity level, can be determined.

[0111] Examples of plant-derived low-density polyethylene (PPE) biomass plastics with a biomass plastic content of 80% or more, preferably 90% or more, as defined by ISO 16620 or ASTM D6866, include Braskem's product names "SBC818," "SPB608," "SBF0323HC," "STN7006," "SEB853," and "SPB681," and films made from these materials can be suitably used.

[0112] Films and sheets containing biomass raw materials such as starch and polylactic acid are also known. These can be selected and used as appropriate depending on the application.

[0113] The biomass film may be a laminate formed by stacking multiple biomass films, or it may be a laminate formed by combining a conventional petroleum-based film with a biomass film. Furthermore, these biomass films may be unstretched or stretched films, and their manufacturing method is not limited.

[0114] (Biodegradable film) Well-known biodegradable films include those made from readily available biodegradable resins. Examples include polycaprolactone, polyvinyl alcohol, polyamide, cellulose ester, lactic acid-based polyester resin, aliphatic polyester resin, or aliphatic aromatic polyester resin. These biodegradable resins may be used individually or in combination of two or more. Among these, aliphatic polyester resin or aliphatic aromatic polyester resin is preferred. Aliphatic polyester resins include aliphatic polyesters obtained by polycondensation reactions of aliphatic diols and aliphatic dicarboxylic acids. Examples of aliphatic diols include ethylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,4-cyclohexanediol, and 1,4-cyclohexanedimethanol. These may be used individually or in mixtures. Among these, 1,4-butanediol is preferred. Examples of aliphatic dicarboxylic acids include oxalic acid, succinic acid, glutanoic acid, adipic acid, sebacic acid, suberic acid, and dodecanedioic acid, and their derivatives, such as acid anhydrides, may also be used. Among these, succinic acid or succinic anhydride, or mixtures of these with adipic acid, are preferred. Specifically, examples include polybutylene succinate (PBS) obtained from 1,4-butanediol and succinic acid (e.g., BioPBS from PPT MCC Biochem), and polybutylene succinate adipate (PBSA) obtained by copolymerizing PBS with adipic acid.

[0115] Aliphatic aromatic polyester resins include copolymers containing aliphatic dicarboxylic acid units, aromatic dicarboxylic acid units, and linear aliphatic and / or alicyclic diol units. The diol component that provides the diol units usually has 2 to 10 carbon atoms, and examples include ethylene glycol, 1,3-propanediol, 1,4-butanediol, and 1,4-cyclohexanedimethanol. Among these, diols with 2 to 4 carbon atoms are preferred, with ethylene glycol and 1,4-butanediol being preferred, and 1,4-butanediol being even more preferred. The dicarboxylic acid component that provides the dicarboxylic acid units usually has 2 to 10 carbon atoms, and examples include succinic acid, adipic acid, suberic acid, sebacic acid, and dodecanedioic acid. Among these, succinic acid or adipic acid are preferred. Examples of aromatic dicarboxylic acid components that provide aromatic dicarboxylic acid units include terephthalic acid, isophthalic acid, and naphthalenedicarboxylic acid. Among these, terephthalic acid and isophthalic acid are preferred, with terephthalic acid being even more preferred. Specifically, examples include PBAT (for example, Ecoflex manufactured by B.A.S.F.), which is a copolymer of 1,4-butanediol, adipic acid, and terephthalic acid.

[0116] Other examples include aliphatic polyester copolymers obtained from hydroxyalkanoic acid and polycarboxylic acid, such as poly(3-hydroxyalkanoate) (in particular, poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH) (e.g., Aonirex manufactured by Kaneka Corporation) and polylactic acid (PLA) (e.g., REVODE manufactured by Kaisei Biomaterials Co., Ltd., and Ingeo manufactured by NatureWorks Inc.).

[0117] The biodegradable film may be a laminate formed by stacking multiple biodegradable films, or a laminate formed by combining a conventional petroleum-based film with a biodegradable film. Furthermore, these biodegradable films may be unstretched or stretched films, and their manufacturing method is not limited.

[0118] The film may be stretched. A common stretching method involves melting and extruding the resin into a sheet using methods such as extrusion film formation, followed by simultaneous biaxial stretching or sequential biaxial stretching. In the case of sequential biaxial stretching, it is common to first perform longitudinal stretching, followed by transverse stretching. Specifically, a method combining longitudinal stretching using the speed difference between rolls and transverse stretching using a tenter is frequently used.

[0119] Various surface treatments, such as flame treatment or corona discharge treatment, may be applied to the film surface as needed to ensure that an adhesive layer free from defects such as film breakage or repulsion is formed.

[0120] Alternatively, a film containing a vapor-deposited layer of metal such as aluminum, a metal oxide such as silica or alumina, or a barrier film containing a gas barrier layer such as polyvinyl alcohol, ethylene-vinyl alcohol copolymer, or vinylidene chloride may be used in combination. By using such films, a laminate can be made that has barrier properties against water vapor, oxygen, alcohol, inert gases, volatile organic compounds (fragrances), etc.

[0121] As for the paper, any known paper substrate can be used without particular limitation. Specifically, it is manufactured using known papermaking natural fibers such as wood pulp and papermaking machines, 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 pulps that have been chemically modified. As for the type of pulp, chemical pulps produced by sulfate pulping, acidic, neutral, and alkaline sulfite pulping, soda salt pulping, etc., as well as gland pulp, chemigland pulp, thermomechanical pulp, etc. can be used. In addition, various commercially available fine papers, coated papers, backing papers, impregnated papers, cardboard, and paperboard can also be used.

[0122] More specifically, the configuration of the laminate is as follows: (1) Substrate 1 / Adhesive layer 1 / Sealant film (2) Substrate 1 / Adhesive layer 1 / Metal vapor-deposited unstretched film (3) Substrate 1 / Adhesive layer 1 / Metal vapor-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 vapor-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 Examples include, but are not limited to, those listed above.

[0123] Examples of substrates 1 used in composition (1) include MDOPE film, OPE film, OPP film, PET film, nylon film, and paper. Alternatively, a substrate 1 coated with a coating for purposes such as improving gas barrier properties or ink receptivity when providing the printing layer described later may be used. 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. The printing layer may be provided on the side of the substrate 1 facing the adhesive layer 1 (or, if a coated substrate film 1 is used, on the side of the coating layer facing the adhesive layer 1) or on the side opposite to 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 general printing methods conventionally used for printing on polymer films and paper.

[0124] Examples of substrate 1 used in configurations (2) and (3) include MDOPE film, OPE film, OPP film, PET film, paper, etc. The adhesive layer 1 is a cured coating of the adhesive of the present invention. Examples of unstretched metal-deposited films include CPP film, LLDPE film, VM-CPP film, VM-LLDPE film, etc., which are gas barrier heat seal films with metal deposition of aluminum or the like. Examples of stretched metal-deposited films include VM-MDOPE film, VM-OPE film, VM-OPP film, etc., which are MDOPE film, OPE film, or OPP film with metal deposition of aluminum or the like. A printed layer may be provided on any surface of the substrate 1 in the same manner as in configuration (1).

[0125] Examples of transparent vapor-deposited stretched films used in configuration (4) include MDOPE films, OPE films, OPP films, PET films, nylon films, etc., on which silica or alumina vapor deposition has been applied. Films with a coating applied to the vapor-deposited layer may also be used for purposes such as protecting the inorganic vapor-deposited layer of silica or alumina. The adhesive layer 1 is a cured coating film of the adhesive of the present invention. The sealant film is the same as that of configuration (1). A printed layer may be provided on the side of the transparent vapor-deposited stretched film facing the adhesive layer 1 (or, if a film with a coating applied to the inorganic vapor-deposited layer is used, on the side of the coating layer facing the adhesive layer 1). The method for forming the printed layer is the same as in configuration (1).

[0126] Examples of substrate 1 used in configuration (5) include PET film and paper. Examples of substrate 2 include nylon film. At least one of adhesive layer 1 and adhesive layer 2 is a cured coating film of the adhesive of the present invention. Examples of sealant film are the same as those in configuration (1). A printed layer may be provided on any surface of substrate 1 in the same manner as in configuration (1).

[0127] The base material 1 of configuration (6) is the same as that of configurations (2) and (3). Examples of metal vapor-deposited stretched films include VM-MDOPE film, VM-OPE film, VM-OPP film, and VM-PET film, which are obtained by vapor deposition of aluminum or other metal onto MDOPE film, OPE film, OPP film, or PET film. At least one of adhesive layer 1 and adhesive layer 2 is a cured coating film of the adhesive of the present invention. Examples of sealant films are the same as those of configuration (1). A printed layer may be provided on any surface of the base material 1 in the same manner as in configuration (1).

[0128] Examples of the substrate 1 in configuration (7) include PET film and paper. Examples of the transparent vapor-deposited stretched film include those the same as in configuration (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 the same as in configuration (1). A printed layer may be provided on any surface of the substrate 1 in the same manner as in configuration (1).

[0129] Examples of the base material 1 in configuration (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 are the same as those in configuration (1). A printed layer may be provided on any surface of the base material 1 in the same manner as in configuration (1).

[0130] Examples of base material 1 in configurations (9) and (10) include PET film and paper. Examples of base material 2 include nylon film. Examples of metal layers include aluminum foil. At least one layer of adhesive layers 1, 2, and 3 is a cured coating of the adhesive of the present invention. Examples of sealant films are the same as those in configuration (1). A printed layer may be provided on any surface of base material 1 in the same manner as in configuration (1).

[0131] Since the adhesive of the present invention has excellent adhesion to metal substrates and metal vapor-deposited layers, when the laminate includes at least one of a metal vapor-deposited film, a transparent vapor-deposited film, and a metal layer, it is preferable that the adhesive layer in contact with the metal vapor-deposited layer, the transparent vapor-deposited layer, and the metal layer, and especially the adhesive on the sealant film side of these layers, is a cured coating of the adhesive of the present invention.

[0132] Furthermore, since the adhesive of the present invention has excellent retort resistance, especially when it contains acidic components, it is also preferable to use it as an adhesive layer in laminates used to contain such contents, for example, in configuration examples (8) to (10).

[0133] The laminate of the present invention may further include other films or substrates in addition to the above-described configurations (1) to (10). As other substrates, in addition to the stretched film, unstretched film, and transparent vapor-deposited film described above, porous substrates such as paper, wood, and leather, as described later, may also be used. The adhesive used when bonding the other substrates may be the adhesive of the present invention or not.

[0134] The "other layer" may contain known additives and stabilizers, such as antistatic agents, easy-adhesion coating agents, plasticizers, lubricants, and antioxidants. The "other layer" may also have its surface pretreated by corona treatment, plasma treatment, ozone treatment, chemical treatment, solvent treatment, etc., to improve adhesion when laminated with other materials.

[0135] The laminate of the present invention can be suitably used in a variety of applications, such as packaging materials for food, pharmaceuticals, and household goods; lids; paper tableware such as paper straws, paper napkins, paper spoons, paper plates, and paper cups; protective wall materials; roofing materials; solar 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 injection molding simultaneous decoration methods; and packaging materials for laundry detergents, kitchen detergents, bath detergents, bath soaps, liquid shampoos, liquid conditioners, and the like.

[0136] <Packaging material> The laminate of the present invention can be used as a multilayer packaging material for the purpose of protecting food, pharmaceuticals, and other products. When used as a multilayer packaging material, the layer configuration may be changed depending on the contents, usage environment, and usage form. Furthermore, the packaging of the present invention may be appropriately provided with an easy-open treatment or resealing means.

[0137] As an example of a specific embodiment of the packaging material of the present invention, a packaging material made by forming a bag from a laminate having a sealant film, such as the laminate configuration examples (1), (4) to (10) described above. The laminate is folded or overlapped so that the inner layers (sealant film surfaces) face each other, and the peripheral edges are heat-sealed to form a bag. Methods for forming the bag include heat sealing methods such as side seal type, two-side seal type, three-side seal type, four-side seal type, envelope seal type, gusset seal type, pleated seal type, flat-bottom seal type, square-bottom seal type, gusset type, and other heat-seal types. The packaging material of the present invention can take various forms depending on the contents, usage environment, and usage form. Self-standing packaging materials (standing pouches) are also possible. Known heat sealing methods include bar seal, rotary roll seal, belt seal, impulse seal, high-frequency seal, and ultrasonic seal.

[0138] Products using the packaging material of the present invention are manufactured by filling the packaging material with contents through its opening and then heat-sealing the opening. Examples of contents that can be filled include, for example, food products such as rice crackers, bean snacks, nuts, biscuits / cookies, wafers, marshmallows, pies, semi-baked cakes, candies, and snack foods; staple foods such as bread, instant noodles, dried noodles, pasta, aseptically packaged rice, rice porridge, packaged mochi, and cereal foods; processed agricultural products such as pickles, boiled beans, natto, miso, frozen tofu, tofu, enoki mushrooms, konjac, processed wild vegetables, jams, peanut cream, salads, frozen vegetables, and processed potato products; processed livestock products such as ham, bacon, sausages, processed chicken products, and corned beef; and fish ham. Examples of processed seafood products include sausages, processed seafood products, fish cakes, seaweed, preserved foods, dried bonito flakes, salted seafood, smoked salmon, and spicy cod roe; fruits such as peaches, oranges, pineapples, apples, pears, and cherries; vegetables such as corn, asparagus, mushrooms, onions, carrots, radishes, and potatoes; frozen and chilled prepared foods such as hamburgers, meatballs, fried seafood, dumplings, and croquettes; dairy products such as butter, margarine, cheese, cream, instant creamy powder, and infant formula; liquid seasonings; retort curry; and pet food.

[0139] Furthermore, as a non-food product, it can be used as a packaging material for various items such as cigarettes, disposable hand warmers, pharmaceuticals such as intravenous fluid packs, liquid laundry detergent, liquid dish soap, liquid bath detergent, liquid bath soap, liquid shampoo, liquid conditioner, cosmetics such as lotions and emulsions, vacuum insulation materials, and batteries. [Examples]

[0140] The present invention will be described in more detail below with reference to specific synthesis examples and embodiments, but the present invention is not limited to these embodiments. In the following examples, "parts" and "%" represent "parts by mass" and "mass%", respectively, unless otherwise specified.

[0141] <Preparation of polyisocyanate composition (X)> (Polyisocyanate composition (X-1)) In a reaction vessel equipped with a stirrer, thermometer, nitrogen gas inlet tube, rectification column, and moisture separator, 72 parts by mass of ethylene glycol, 158 parts by mass of diethylene glycol, 225 parts by mass of neopentyl glycol, 110 parts by mass of hexane glycol, 219 parts by mass of adipic acid, 46 parts by mass of sebaciic acid, and 280 parts by mass of isophthalic acid were charged under nitrogen gas introduction. The temperature was gradually increased under atmospheric pressure and nitrogen flow, and the reaction was carried out to 250°C while dehydration was performed, and the reaction was carried out at 250°C for 2 hours. After confirming that the contents were clear and the top temperature of the rectification column was below 80°C, the temperature was reduced to 240°C, the rectification column was switched to a condenser, a line was connected to a vacuum pump, and the reaction was continued under reduced pressure of 30-60 Torr until the predetermined acid value and viscosity were reached, yielding polyester polyol (PES-1). The acid value of the reaction product (PES-1) was 0.8 mg KOH / g, and the hydroxyl value was 265.0 mg KOH / g.

[0142] In a reaction vessel equipped with a stirrer, thermometer, nitrogen gas inlet tube, and condenser, 550 parts of xylylene diisocyanate (XDI) and 42.8 parts by mass of 5-(2,5-dioxotetrahydro-3-furanyl)-3-methyl-3-cyclocarboxylic acid anhydride (DIC Epiclon B-4500) were charged. The mixture was heated to 90°C while stirring under a nitrogen gas stream, and stirring continued at 90°C until the liquid became clear. Once clear, the temperature was reduced to 60°C. Subsequently, 450 parts by mass of polyester polyol (PES-1) were added, taking care to avoid exothermic reaction. The mixture was then heated to 80°C and reacted at 80°C for 2 hours. Next, using a thin-film distillation apparatus, the reaction product of XDI and polyester polyol, a urethane prepolymer, was purified at a pressure of approximately 0.02 Torr and a temperature of 160°C until the amount of XDI in the urethane prepolymer was 0.05% by mass of the solid content, thereby obtaining polyurethane polyisocyanate (A1-1). The NCO% of polyurethane polyisocyanate (A1-1) was 7.6%.

[0143] 1000 parts of hexamethylene diisocyanate (HDI) were added to a reaction vessel equipped with a stirrer, thermometer, nitrogen gas inlet tube, and condenser, and heated to 60°C while stirring. 0.5 parts of quaternary ammonium salt were added dropwise, and when the desired refractive index was reached, a deactivator was added as needed to terminate the reaction. Next, using a thin-film distillation apparatus, the isocyanate derivative (A2-1) was obtained by purifying the nurate product of HDI, which was a reaction product of HDI, at a pressure of approximately 0.02 Torr and a temperature of 160°C until the amount of HDI in the nurate was 0.05% by mass of the solid content. The NCO% of the isocyanate derivative (A2-1) was 21.8%.

[0144] In a reaction vessel equipped with a stirrer, thermometer, and nitrogen gas inlet tube, 700 parts by mass of polyurethane polyisocyanate (A1-1) and 300 parts by mass of isocyanate derivative (A2-1) were charged, and the mixture was heated to 60°C while stirring under a nitrogen gas stream. Stirring was continued at 60°C until the liquid became clear, and then the temperature was lowered to obtain polyisocyanate composition (X-1). The NCO% of polyisocyanate composition (X-1) was 12.3%, the residual XDI was 0.04%, and the residual HDI was 0.04% by mass. Furthermore, the calculated acid value when the acid anhydride group in polyisocyanate composition (X-1) was ring-opened was 25.5 mgKOH / g.

[0145] (Polyisocyanate composition (X-2)) In a reaction vessel equipped with a stirrer, thermometer, nitrogen gas inlet tube, and condenser, 785 parts of tolylene diisocyanate (TDI) and 30 parts of 5-(2,5-dioxotetrahydro-3-furanyl)-3-methyl-3-cyclocarboxylic acid anhydride (DIC Epiclon B-4500) were charged. The mixture was heated to 90°C while stirring under a nitrogen gas stream, and stirring continued at 90°C until the liquid became clear. Once clear, the temperature was reduced to 60°C. Subsequently, 535 parts of bifunctional polypropylene glycol (AGC Exenol 420) were added, taking care to avoid exothermic reaction. The mixture was then heated to 80°C and reacted at 80°C for 2 hours. Next, using a thin-film distillation apparatus, the TDI in the urethane prepolymer, which is the reaction product of TDI and polypropylene glycol, was purified at a pressure of approximately 0.02 Torr and a temperature of 160°C until the TDI content in the solids was 0.04% by mass, thereby obtaining polyisocyanate composition (X-2). The NCO% of polyisocyanate composition (X-2) was 11.2%. Furthermore, the calculated acid value when the acid anhydride group in polyisocyanate composition (X-1) was opened was 25.5 mgKOH / g.

[0146] (Polyisocyanate composition (X-3)) In a reaction vessel equipped with a stirrer, thermometer, nitrogen gas inlet tube, and condenser, 550 parts of xylylene diisocyanate (XDI) and 7.1 parts of 5-(2,5-dioxotetrahydro-3-furanyl)-3-methyl-3-cyclocarboxylic acid anhydride (DIC Epiclon B-4500) were charged. The mixture was heated to 90°C while stirring under a nitrogen gas stream, and stirring continued at 90°C until the liquid became clear. Once clear, the temperature was reduced to 60°C. Subsequently, 450 parts of polyester polyol (PES-1) were added, taking care to avoid exothermic reactions. The mixture was then heated to 80°C and reacted at 80°C for 2 hours. Next, using a thin-film distillation apparatus, the reaction product of XDI and polyester polyol, a urethane prepolymer, was purified at a pressure of approximately 0.02 Torr and a temperature of 160°C until the amount of XDI in the urethane prepolymer was 0.05% by mass of the solid content, thereby obtaining polyurethane polyisocyanate (A1-2). The NCO% of polyurethane polyisocyanate (A1-2) was 7.6%.

[0147] In a reaction vessel equipped with a stirrer, thermometer, and nitrogen gas inlet tube, 700 parts by mass of polyurethane polyisocyanate (A1-2) and 300 parts by mass of isocyanate derivative (A2-1) were charged, and the mixture was heated to 60°C while stirring under a nitrogen gas stream. Stirring was continued at 60°C until the liquid became clear, and then the temperature was lowered to obtain polyisocyanate composition (X-3). The NCO% of polyisocyanate composition (X-3) was 12.3%, the residual XDI was 0.04% by mass, and the residual HDI was 0.04% by mass. The acid value (calculated value) of polyisocyanate composition (X-3) at the time of ring opening of the acid anhydride group was 4.2 mgKOH / g.

[0148] (Polyisocyanate composition (X-4)) In a reaction vessel equipped with a stirrer, thermometer, nitrogen gas inlet tube, and condenser, 785 parts of tolylene diisocyanate (TDI) and 5 parts by mass of pyromellitic anhydride were charged. The mixture was heated to 90°C while stirring under a nitrogen gas stream, and stirring continued at 90°C until the liquid became clear. Once clear, the temperature was reduced to 60°C. Subsequently, 535 parts by mass of bifunctional polypropylene glycol (AGC Exenol 420) was added, taking care to avoid exothermic reactions. The mixture was then heated to 80°C and reacted at 80°C for 2 hours. Next, using a thin-film distillation apparatus, the TDI in the urethane prepolymer, which is the reaction product of TDI and polypropylene glycol, was purified at a pressure of approximately 0.02 Torr and a temperature of 160°C until the TDI content in the solids was 0.04% by mass, thereby obtaining polyurethane polyisocyanate (A1-3), which was used as polyisocyanate composition (X-4). The NCO% of polyisocyanate composition (X-4) was 11.2%. Furthermore, the calculated acid value when the acid anhydride group in the polyisocyanate composition (X-4) was ring-opened was 5.1 mg KOH / g.

[0149] (Polyisocyanate composition (X-5)) In a reaction vessel equipped with a stirrer, thermometer, nitrogen gas inlet tube, and condenser, 550 parts by mass of xylylene diisocyanate (XDI) and 30 parts by mass of 5-(2,5-dioxotetrahydro-3-furanyl)-3-methyl-3-cyclocarboxylic acid anhydride (DIC Epiclon B-4500) were charged. The mixture was heated to 90°C while stirring under a nitrogen gas stream, and stirring continued at 90°C until the liquid became clear. Once clear, the temperature was reduced to 60°C. Subsequently, 450 parts by mass of polyester polyol (PES-1) were added, taking care to avoid exothermic reaction. The mixture was then heated to 80°C and reacted at 80°C for 2 hours. Next, using a thin-film distillation apparatus, the reaction product of XDI and polyester polyol, a urethane prepolymer, was purified at a pressure of approximately 0.02 Torr and a temperature of 160°C until the amount of XDI in the urethane prepolymer was 1.40% by mass of the solid content, thereby obtaining polyurethane polyisocyanate (A1-4). The NCO% of polyurethane polyisocyanate (A1-4) was 7.6%.

[0150] In a reaction vessel equipped with a stirrer, thermometer, and nitrogen gas inlet tube, 700 parts by mass of polyurethane polyisocyanate (A1-4) and 300 parts by mass of isocyanate derivative (A2-1) were charged, and the mixture was heated to 60°C while stirring under a nitrogen gas stream. Stirring was continued at 60°C until the liquid became clear, and then the temperature was lowered to obtain polyisocyanate composition (X-5). The NCO% of polyisocyanate composition (X-5) was 12.3%, the residual XDI was 1.00%, and the residual HDI was 0.04%. The acid value (calculated value) at the ring-opening of the acid anhydride group in polyisocyanate composition (X-5) was 25.5 mgKOH / g.

[0151] (Polyisocyanate composition (X-6)) In a reaction vessel equipped with a stirrer, thermometer, and nitrogen gas inlet tube, 800 parts by mass of isocyanate derivative (A2-1), 200 parts by mass of isophorone diisocyanate nurate (EVONIK VESTANAT T-1890 / 100 NCO% 17.3), and 30 parts by mass of 5-(2,5-dioxotetrahydro-3-furanyl)-3-methyl-3-cyclocarboxylic acid anhydride (DIC Epiclon B-4500) were charged, and the mixture was heated to 130°C while stirring under a nitrogen gas stream. Stirring was continued at 130°C until the liquid became clear, and then the temperature was lowered to obtain polyisocyanate composition (X-6). The NCO% of polyisocyanate composition (X-6) was 20.9%, and the residual HDI was 0.04%. Furthermore, the calculated acid value at the time of ring-opening of the acid anhydride group in the polyisocyanate composition (X-6) was 25.5 mg KOH / g.

[0152] (Polyisocyanate composition (X-7)) In a reaction vessel equipped with a stirrer, thermometer, nitrogen gas inlet tube, and condenser, 550 parts by mass of xylylene diisocyanate (XDI) was charged. The mixture was heated to 90°C while stirring under a nitrogen gas stream, and stirring continued at 90°C until the liquid became clear. Once clear, the temperature was reduced to 60°C. Subsequently, 450 parts by mass of polyester polyol (PES-1) was charged, taking care to avoid exothermic reactions. The mixture was then heated to 80°C and reacted at 80°C for 2 hours. Next, using a thin-film distillation apparatus, the reaction product of XDI and polyester polyol, a urethane prepolymer, was purified to a solid content of 0.05% by mass of XDI until the XDI content in the urethane prepolymer was 0.05% by mass. This yielded polyurethane polyisocyanate (A1-5). The NCO% of polyurethane polyisocyanate (A1-5) was 7.6%.

[0153] In a reaction vessel equipped with a stirrer, thermometer, and nitrogen gas inlet tube, 700 parts by mass of polyurethane polyisocyanate (A1-5) and 300 parts by mass of isocyanate derivative (A2-1) were charged, and the mixture was heated to 60°C while stirring under a nitrogen gas stream. Stirring was continued at 60°C until the liquid became clear, and then the temperature was lowered to obtain polyisocyanate composition (X-7). The NCO% of polyisocyanate composition (X-7) was 12.3%, the residual XDI was 0.04%, and the residual HDI was 0.04%.

[0154] (Polyisocyanate composition (X-8)) 785 parts by mass of tolylene diisocyanate (TDI) were charged into a reaction vessel equipped with a stirrer, thermometer, nitrogen gas inlet tube, and condenser. The mixture was heated to 90°C while stirring under a nitrogen gas stream, and stirring continued at 90°C until the liquid became clear. Once clear, the temperature was lowered to 60°C. Subsequently, 535 parts by mass of bifunctional polypropylene glycol (AGC Exenol 420) were charged, taking care to avoid exothermic reactions. The mixture was then heated to 80°C and reacted at 80°C for 2 hours. Next, using a thin-film distillation apparatus, the TDI in the urethane prepolymer, which is the reaction product of TDI and polypropylene glycol, was purified at a pressure of approximately 0.02 Torr and a temperature of 160°C until the TDI content in the solids was 0.04% by mass, thereby obtaining polyurethane polyisocyanate (A1-6), which was used as polyisocyanate composition (X-8). The NCO% of polyisocyanate composition (X-8) was 11.2%.

[0155] <Preparation of polyol composition (Y)> (Polyol composition (Y-1)) In a reaction vessel equipped with a stirrer, thermometer, nitrogen gas inlet tube, rectification tube, and moisture separator, 400 parts by mass of propylene glycol, 80 parts by mass of trimethylolpropane, 700 parts by mass of adipic acid, and 0.1 parts by mass of titanium tetraisopropoxide were charged under nitrogen gas introduction. 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 250°C. The esterification reaction was terminated when the acid value became 1 mg KOH / g or less, and polyol composition (Y-1) was obtained. The hydroxyl value of polyol composition (Y-1) was 152 mg KOH / g.

[0156] (Polyol composition (Y-2)) Castor oil (manufactured by Ito Oil Co., Ltd.) was used as the polyol composition (Y-2).

[0157] (Polyol composition (Y-3)) In a reaction vessel equipped with a stirrer, thermometer, nitrogen gas inlet tube, rectification tube, and moisture separator, 540 parts of 3-methylpentanediol, 460 parts of isophthalic acid, and 0.1 parts of titanium tetraisopropoxide were charged under nitrogen gas introduction. 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 250°C. The esterification reaction was terminated when the acid value fell to 1 mg KOH / g or less to obtain polyester polyol (C1). The hydroxyl value of polyester polyol (C1) was 224 mg KOH / g.

[0158] In a reaction vessel equipped with a stirrer, 300 parts by mass of polyester polyol (C1), 400 parts by mass of polypropylene glycol (AGC, exenol 420), 120 parts by mass of polypropylene polyol (AGC, exenol 430), and 0.5 parts by mass of dibutyltin dilaurate were charged, and the mixture was heated to 60°C while stirring. Stirring was continued at 60°C until the liquid became clear, and then polyoxypropylene triamine (Huntsman, Jeffermin T-403) was added, and stirring was continued at 60°C until the liquid became clear to obtain polyol composition (Y-3). The hydroxyl value of polyol composition (Y-3) was 227.2 mg KOH / g, and the amine value was 60.7 mg KOH / g.

[0159] (Polyol composition (Y-4)) In a reaction vessel equipped with a stirrer, 950 parts by mass of polyester polyol (C1) and 50 parts by mass of 5-(2,5-dioxotetrahydro-3-furanyl)-3-methyl-3-cyclocarboxylic anhydride (DIC Epiclon B-4500) were charged, and the mixture was heated to 90°C while stirring. Stirring was continued at 90°C until the liquid became clear, and then the temperature was lowered to obtain polyol composition (Y-4). The hydroxyl value of polyol composition (Y-4) was 152 mgKOH / g, and the acid value at the time of ring opening of the acid anhydride group was 42.5 mgKOH / g.

[0160] <Manufacturing of evaluation samples> (Example 1) The adhesive of Example 1 was prepared by stirring and mixing 1.4 parts of polyisocyanate composition (X-1) and 0.6 parts of polyol composition (Y-1). 2.0 g / m² of the adhesive of Example 1 was applied to a PET film (Toyobo Co., Ltd., E5102, 12 μm). 2 The adhesive was applied to the aluminum foil (9 μm) and pressed with a nip roll (50°C). Subsequently, 2.0 g / m of the adhesive from Example 1 was applied to the aluminum foil. 2 The material was applied in this manner and then pressed with a CPP film (Toray Film Processing Co., Ltd., Trefan ZK-207, 70 μm) using a nip roll (50°C). After aging at 40°C for 3 days, a PET / Al / CPP laminate 1 was obtained.

[0161] Laminate 1 was cut to 100mm x 200mm, folded so that the CPP film was on the inside, and heat-sealed at 1 atm, 210°C, and 1 second to create a pouch. A test piece was created by filling it with 1 / 1 / 1 sauce (meat sauce:vegetable oil:vinegar = 1:1:1) as the contents.

[0162] (Examples 2-4) Evaluation samples for Examples 2 to 4 were obtained in the same manner as in Example 1, except that the adhesives shown in Table 1 were used.

[0163] (Example 5) A polyisocyanate composition (X-1) was applied to a PET film, and a polyol composition (Y-3) was applied to an aluminum foil. The PET and aluminum foil were then pressed together using a nip roll (50°C). The application amounts of the polyisocyanate composition (X-1) and polyol composition (Y-3) were 1.4 g / m² each. 2 0.6g / m 2 Next, the polyisocyanate composition (X-1) was applied to the aluminum foil, and the polyol composition (Y-3) was applied to the CPP film. After aging at 40°C for 3 days, a PET / Al / CPP laminate 1 was obtained. The application amounts of the polyisocyanate composition (X-1) and polyol composition (Y-3) were 1.4 g / m² each. 2 0.6g / m 2 That was the case.

[0164] A test piece filled with contents was prepared in the same manner as in Example 1, except that laminate 1 prepared in Example 5 was used.

[0165] (Comparative Examples 1-4) Evaluation samples for Comparative Examples 1 to 4 were obtained in the same manner as in Example 1, except that the adhesives shown in Table 2 were used. (Comparative Examples 5 and 6) Evaluation samples for Comparative Examples 5 and 6 were obtained using the same method as Example 5, except that the adhesives shown in Table 2 were used.

[0166] <Rating> (Normal adhesive strength) The adhesive strength (N / 15mm) between the aluminum foil and CPP film of laminate 1 was measured using a tensile testing machine at a 25°C atmosphere with a peeling speed of 300 mm / min, employing a T-type peeling method. The results were evaluated on a five-point scale and summarized in Tables 1 and 2. 5: Adhesive strength of 4N / 15mm or more 4: Adhesion strength of 3N / 15mm or more and less than 4N / 15mm 3: Adhesion strength of 2N / 15mm or more and less than 3N / 15mm 2: Adhesion strength less than 2N / 15mm 1: Delamination occurred before adhesive strength measurement.

[0167] (Retort resistance level 1) Test pieces were retorted using a shower-type retort sterilization device (Flavor Ace, manufactured by Hisaka Works) at 121°C for 30 minutes. After retorting, the test pieces were opened and their adhesive strength was measured in the same manner as for normal adhesive strength. The results are summarized in Tables 1 and 2.

[0168] (Retort resistance level 2) Test pieces were retorted using a shower-type retort sterilization device (Flavor Ace, manufactured by Hisaka Works) at 121°C for 30 minutes. After retorting, the test pieces were stored at 50°C for 4 weeks, then opened and their adhesive strength was measured in the same manner as for normal adhesive strength. The results are summarized in Tables 1 and 2.

[0169] [Table 1]

[0170] [Table 2]

Claims

1. The material comprises a polyisocyanate composition (X) and a polyol composition (Y), The polyisocyanate composition (X) comprises a polyurethane polyisocyanate (A1), which is a reaction product of a polyisocyanate (l) and a polyol (m), and an acid anhydride (B), wherein the polyisocyanate (l) does not contain 4,4'-diphenylmethane diisocyanate, the acid value derived from the acid anhydride (B) in the polyisocyanate composition (X) is 1 mg KOH / g or more and 100 mg KOH / g or less, and the content of diisocyanate monomer in the polyisocyanate composition (X) is 0.1% by mass or less. A method for producing a polyisocyanate composition (X) used in a two-component, solvent-free adhesive, wherein the polyol composition (Y) contains a polyol (C), A method for producing the polyisocyanate composition (X) obtained by heating a composition containing the polyurethane polyisocyanate (A1) and the acid anhydride (B).

2. The manufacturing method according to claim 1, wherein the polyisocyanate (l) is at least one selected from aromatic diisocyanates, aromatic aliphatic diisocyanates, and alicyclic diisocyanates.

3. The manufacturing method according to claim 1, wherein the acid anhydride (B) is a non-aromatic carboxylic acid anhydride.

4. The polyol (C) includes polyester polyol (C1), The manufacturing method according to claim 1, wherein the content of the polyester polyol (C1) in the polyol (C) is 20% by mass or more.

5. The method for producing the product according to claim 4, wherein the polyester polyol (C1) is a reaction product of a polyhydric alcohol and a polyhydric carboxylic acid, and the polyhydric carboxylic acid includes an aromatic polyhydric carboxylic acid.

6. The manufacturing method according to claim 4, wherein the hydroxyl value of the polyester polyol (C1) is 20 mg KOH / g or more and 400 mg KOH / g or less.

7. The manufacturing method according to claim 1, wherein the polyol (C) comprises a polyether polyol (C2).

8. The manufacturing method according to claim 7, wherein the hydroxyl value of the polyether polyol (C2) is 20 mg KOH / g or more and 400 mg KOH / g or less.

9. The manufacturing method according to claim 1, wherein the polyisocyanate (l) is at least one selected from toluene diisocyanate, xylene diisocyanate, and isophorone diisocyanate.

10. The manufacturing method according to claim 1, wherein the heating step is a step of heating the polyurethane polyisocyanate (A1) and the acid anhydride (B) to 50°C to 150°C.

11. The manufacturing method according to claim 1, wherein the heating step is a step of removing the polyisocyanate (l) from a composition comprising the polyurethane polyisocyanate (A1), the polyisocyanate (l), and the acid anhydride (B) using a distillation apparatus.

12. Polyurethane polyisocyanate (A1), which is a reaction product of polyester polyol (l) and polyisocyanate (m), It contains acid anhydride (B), The polyisocyanate (l) does not contain 4,4'-diphenylmethane diisocyanate. The acid value derived from the aforementioned acid anhydride (B) is 1 mg KOH / g or more and 100 mg KOH / g or less. The content of diisocyanate monomer is 0.1% by mass or less. It does not contain solvents, A method for producing a polyisocyanate composition, comprising the step of heating a composition containing the polyurethane polyisocyanate (A1) and the acid anhydride (B).

13. The method for producing a polyisocyanate composition according to claim 12, wherein the heating step is a step of heating the polyurethane polyisocyanate (A1) and the acid anhydride (B) to 50°C to 150°C.

14. The method for producing a polyisocyanate composition according to claim 12, wherein the heating step is a step of removing the polyisocyanate (l) from a composition comprising the polyurethane polyisocyanate (A1), the polyisocyanate (l), and the acid anhydride (B) using a distillation apparatus.

15. A method for manufacturing a laminate, comprising the step of bonding a first substrate and a second substrate via a two-component curing adhesive, wherein the two-component curing adhesive comprises a polyisocyanate composition (X) and a polyol composition (Y), and the polyisocyanate composition (X) is obtained by the manufacturing method described in any one of claims 1 to 11.

16. The method for manufacturing a laminate according to claim 15, wherein the first substrate is a metal foil.

17. The method for manufacturing a laminate according to claim 15, wherein the first substrate has a metal vapor deposition layer.

18. A method for manufacturing a packaging material, comprising the step of forming a bag from the laminate described in claim 15.

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