Method for manufacturing laminates, laminates, packaging materials

Abstract

This invention provides a method for manufacturing laminates that can accommodate small-volume production and short delivery times. [Solution] A method for manufacturing a laminate comprising a first substrate, a printed layer, an adhesive layer which is a cured coating film of a two-component curable adhesive containing a polyol composition (X) and a polyisocyanate composition (Y), and a second substrate, wherein the laminate is arranged in this order, the method comprising the steps of: providing a printed layer on the first substrate by inkjet printing; applying a first coating agent on the printed layer; applying a second coating agent on the second substrate; and bonding the first substrate and the second substrate together so that the first coating agent and the second coating agent are in contact, wherein the first coating agent contains one of the polyol composition (X) and the polyisocyanate composition (Y), and the second coating agent contains the other of the polyol composition (X) and the polyisocyanate composition (Y).

Description

[Technical Field]

[0001] The present invention relates to a method for manufacturing a laminate, a laminate manufactured by said method, and a packaging material obtained by forming a bag from said laminate. [Background technology]

[0002] Flexible packaging materials used for food, pharmaceuticals, cosmetics, etc., are laminates formed by bonding plastic films together, or / or a plastic film with a metal-deposited film or metal foil. Generally, a laminate that can be used as flexible packaging material is obtained by bonding separately prepared materials such as plastic films, metal-deposited films, and metal foils to a plastic film that has a printed layer formed on it using an adhesive. Gravure printing and flexographic printing are widely used as methods for forming a printed layer on a plastic film. Both gravure printing and flexographic printing are printing methods that transfer ink to a pre-prepared plate, and are suitable for high-speed printing and mass production.

[0003] For the manufacture of laminates, a two-component curing urethane-based adhesive containing a polyol composition and a polyisocyanate composition is used. The adhesive application method has been either a dry lamination method, where the components are mixed immediately before application and applied to a plastic film; if the adhesive contains a volatile organic solvent, it is passed through an oven to evaporate the organic solvent; and another plastic film is bonded to the film; or a non-solvent lamination method, similar to the dry lamination method, is used, except that the step of evaporating the organic solvent is omitted if the adhesive does not contain an organic solvent. The polyol composition and polyisocyanate composition are designed to have a reactivity such that their viscosity does not increase excessively during application (maintaining a viscosity suitable for application). After bonding the films together, the adhesive reaction progresses and physical properties are exhibited by heating (aging) for several days (Patent Document 1). [Prior art documents] [Patent Documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2014-159548 [Overview of the Initiative] [Problems that the invention aims to solve]

[0005] In recent years, the flexible packaging materials market has seen a trend toward increased product variety and shorter product cycles, driven by changing and diversifying consumer needs. However, as long as the above-mentioned printing and lamination methods are employed, printing requires printing plates, making small-scale production unprofitable. Furthermore, the time required for plate creation and bonding makes it difficult to meet short delivery deadlines.

[0006] This invention has been made in view of these circumstances, and aims to provide a method for manufacturing laminates that can accommodate small-volume production and short delivery times. [Means for solving the problem]

[0007] The present invention relates to a method for manufacturing a laminate in which a first substrate, a printed layer, an adhesive layer which is a cured coating film of a two-component curable adhesive containing a polyol composition (X) and a polyisocyanate composition (Y), and a second substrate are arranged in this order, comprising the steps of: providing a printed layer on the first substrate by inkjet printing; applying a first coating agent on the printed layer; applying a second coating agent on the second substrate; and bonding the first substrate and the second substrate together so that the first coating agent and the second coating agent are in contact, wherein the first coating agent contains one of the polyol composition (X) and the polyisocyanate composition (Y), and the second coating agent contains the other of the polyol composition (X) and the polyisocyanate composition (Y). [Effects of the Invention]

[0008] According to the present invention, since no printing plate is required, it can be used for small-scale production and the printing process can be shortened. Furthermore, since the two-component curing adhesive is applied without mixing, the reactivity of the adhesive can be increased and the aging time can be shortened. Therefore, it is possible to provide a method for manufacturing laminates that can be used for small-scale production and meet short delivery times. [Brief explanation of the drawing]

[0009] [Figure 1] Figure 1 is a schematic diagram of a laminating apparatus 1 used in the manufacturing method of the laminate of the present invention. [Figure 2] Figure 2 is a schematic diagram showing the configuration of the first coating apparatus 12. [Figure 3] Figure 3 is a schematic diagram showing the configuration of the second coating apparatus 22. [Figure 4] Figure 4 is a schematic diagram showing another embodiment of the second coating apparatus 22. [Figure 5] Figure 5 is a schematic diagram showing the configuration of the laminator 30. [Modes for carrying out the invention]

[0010] <Method for manufacturing laminates> The present invention provides a method for manufacturing a laminate, comprising the steps of: providing a printed layer on a first substrate by inkjet printing; applying one component of a two-component curing adhesive onto the printed layer of the first substrate; applying the other component of a two-component curing adhesive to a second substrate; bonding the first substrate and the second substrate together via the two-component curing adhesive; and curing the two-component curing adhesive.

[0011] (base material) There are no particular restrictions on the first and second base materials used in the manufacture of the laminate, and they can be appropriately selected according to the application. 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 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.

[0012] Furthermore, it is also preferable to use biomass film made from materials containing biomass-derived components. Biomass film is sold by various companies, and for example, sheets listed in the biomass certified product list provided by the Japan Organic Resources Association can be used.

[0013] 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.

[0014] For example, as an alternative to polyethylene terephthalate films using conventional petroleum-based raw materials, films containing biomass polyesters such as biomass polyesters using ethylene glycol derived from biomass as a diol unit and dicarboxylic acids derived from fossil fuels as dicarboxylic acid units, biomass polyethylene terephthalate, etc. are known.

[0015] The dicarboxylic acid units of the biomass polyester use dicarboxylic acids derived from fossil fuels. As the dicarboxylic acid, aromatic dicarboxylic acids, aliphatic dicarboxylic acids, and their derivatives can be used without limitation. In addition to the above diol component and dicarboxylic acid component, a copolymer polyester obtained by adding a copolymerization component as a third component such as at least one polyfunctional compound selected from the group consisting of bifunctional oxycarboxylic acids, polyhydric alcohols having three or more functional groups, polycarboxylic acids having three or more functional groups and / or their anhydrides, and oxycarboxylic acids having three or more functional groups may also be used.

[0016] Also, for example, as an alternative to polyolefin films using conventional petroleum-based raw materials, biomass polyolefin films such as biomass polyethylene-based films containing polyethylene-based resins using ethylene glycol derived from biomass as a raw material, biomass polyethylene - polypropylene-based films, etc. are known. The polyethylene-based resin is not particularly limited except that a part of the raw material uses the ethylene glycol derived from biomass, and examples include homopolymers of ethylene, copolymers of ethylene and α-olefins having ethylene as a main component (ethylene-α-olefin copolymers containing 90% by mass or more of ethylene units), etc. These can be used alone or in combination of two or more.

[0017] 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.

[0018] 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.

[0019] 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.

[0020] 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.

[0021] 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.

[0022] 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.

[0023] 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.

[0024] Alternatively, inorganic vapor-deposited films such as metal vapor-deposited films with a metal layer such as aluminum, or transparent vapor-deposited films with laminated layers of metal oxides such as silica or alumina, or barrier films containing a gas barrier layer such as polyvinyl alcohol, ethylene-vinyl alcohol copolymer, or vinylidene chloride may be used. By using such films, a laminate can be made that has barrier properties against water vapor, oxygen, alcohol, inert gases, volatile organic substances (fragrances), etc.

[0025] 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.

[0026] (Printing layer) The printed layer is formed by inkjet printing on a first substrate or a second substrate, either directly or via a primer layer described later. The following description will focus on the case where the printed layer is formed on the first substrate, but the same procedure can be followed when the printed layer is formed on the second substrate instead of the first. The printing ink used to form the printed layer is not particularly limited and can be any conventionally known aqueous inkjet ink. Examples include a colored ink containing a pigment, an aqueous resin, and an aqueous solvent, or a clear ink containing an aqueous resin and an aqueous solvent but without a coloring pigment.

[0027] (Pigment) There are no particular restrictions on the pigments used; either inorganic or organic pigments may be used, and lake pigments and fluorescent pigments may also be used. Extender pigments may also be used in combination as needed. Examples of inorganic pigments include carbon black, titanium dioxide, iron oxide, red iron oxide, metal oxides such as chromium oxide, and pearlescent pigments. In particular, carbon black is preferred for black inks. Examples of carbon black include furnace black, thermal lamp black, acetylene black, and channel black.

[0028] Specific examples of organic pigments include azo pigments such as azo lake pigments, insoluble monoazo pigments, insoluble disazo pigments, and chelate azo pigments; and polycyclic pigments such as phthalocyanine pigments, perylene pigments, perinone pigments, anthraquinone pigments, quinacridone pigments, dioxazine pigments, thioindigo pigments, isoindolinone pigments, quinophthalone pigments, diketopyrrolopyrrole pigments, benzimidazolone pigments, and slene pigments. Examples of extender pigments include silica, calcium carbonate, and talc.

[0029] Furthermore, the use of self-dispersing pigments is also preferable. Examples of self-dispersing pigments include those obtained by physically or chemically treating the pigment to bond (graft) a dispersibility-imparting group, or an active species having a dispersibility-imparting group, to the surface of the pigment. Self-dispersing pigments can be produced, for example, by vacuum plasma treatment, oxidation treatment with hypohalite and / or hypohalite salts; oxidation treatment with ozone; a wet oxidation method in which the pigment surface is oxidized with an oxidizing agent in water; or by bonding p-aminobenzoic acid to the pigment surface to bond carboxyl groups via phenyl groups.

[0030] The hue is not particularly limited; achromatic pigments such as white, black, and gray, as well as chromatic pigments such as yellow, magenta, cyan, blue, red, orange, and green, can all be used.

[0031] Pigments may be used individually or in combination of two or more types. When using two or more types in combination, pigments of the same hue may be used, or pigments of different hues may be used. The printing ink used in this invention can be a mixture of multiple pigments to bring the hue and color development of the printed material within a suitable range. For example, to a black ink using carbon black, a small amount of one or more pigments selected from cyan, magenta, orange, and brown pigments can be added to improve the color at low print density.

[0032] For printing inks other than white, considering color development, inkjet printability, and storage stability of the printing ink, the colorant content is preferably 2% to 20% by mass, more preferably 2.5% to 15% by mass, and particularly preferably 3% to 10% by mass, based on the total amount of printing ink. For white printing inks, considering opacity, inkjet printability, and storage stability of the printing ink, the colorant content is preferably 5% to 40% by mass, and more preferably 8% to 30% by mass, based on the total amount of printing ink.

[0033] Water-based resins are resins that can be dissolved or dispersed in aqueous solvents. Examples of water-based resins include vinyl resins, urethane resins, and polyesters.

[0034] Vinyl resin is a homopolymer or copolymer of ethylenically unsaturated monomers. Examples of monomer arrangements constituting the copolymer include random copolymers, alternating copolymers, block copolymers, and graft copolymers, all of which are preferably used. There are no particular restrictions on the polymerization method; conventionally known methods can be used.

[0035] Known ethylenically unsaturated monomers can be used alone or in combination, including acrylic acid, methacrylic acid, carboxymethyl (meth)acrylate, carboxyethyl (meth)acrylate, acryloyloxyethyl succinic acid, methacryloyloxyethyl succinic acid, acryloyloxyethyl phthalic acid, methacryloyloxyethyl phthalic acid, acryloyloxyisobutyric acid, methacryloyloxyisobutyric acid, crotonic acid, itaconic acid, maleic acid, fumaric acid, citraconic acid, 2-sulfoethyl (meth)acrylate, acryloyloxyethyl phosphonic acid, methacryloyloxyethyl phosphonic acid, 2-(phosphonooxy)ethyl (meth)acrylate, vinyl sulfonic acid, styrene carboxylic acid, styrene sulfonic acid, styrene phosphonic acid, and other ethylenically unsaturated monomers having acid groups.

[0036] Ethylene-unsaturated monomers having hydroxyl groups, such as hydroxyethyl methacrylate, hydroxyethyl acrylate, and 4-hydroxybutyl acrylate.

[0037] Styrene monomers such as styrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, α-methylstyrene, p-ethylstyrene, 2,4-dimethylstyrene, pn-butylstyrene, p-tert-butylstyrene, pn-hexylstyrene, p-methoxystyrene, p-phenylstyrene, etc.

[0038] Alkyl-containing (meth)acrylic monomers such as methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, butyl (meth)acrylate, isobutyl (meth)acrylate, pentyl (meth)acrylate, hexyl (meth)acrylate, octyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, nonyl (meth)acrylate, decyl (meth)acrylate, lauryl (meth)acrylate, myristyl (meth)acrylate, cetyl (meth)acrylate, stearyl (meth)acrylate, behenyl (meth)acrylate, tetratriacontanoyl (meth)acrylate, hexatriacontanoyl (meth)acrylate, etc.

[0039] Alkylene oxide chain-containing (meth)acrylic monomers such as (poly)ethylene glycol mono(meth)acrylate, (poly)propylene glycol mono(meth)acrylate, (poly)butylene glycol mono(meth)acrylate, (poly)(ethylene glycol-propylene glycol) mono(meth)acrylate, (poly)ethylene glycol mono(meth)acrylate monomethyl ether, (poly)ethylene glycol mono(meth)acrylate monobutyl ether, (poly)ethylene glycol mono(meth)acrylate monooctyl ether, (poly)ethylene glycol mono(meth)acrylate monobenzyl ether, (poly)ethylene glycol mono(meth)acrylate monophenyl ether, (poly)ethylene glycol mono(meth)acrylate monohexadecyl ether, (poly)ethylene glycol mono(meth)acrylate monooctadecyl ether, etc.

[0040] Aromatic ring-containing (meth)acrylic monomers such as phenyl (meth)acrylate, benzyl (meth)acrylate, and phenoxyethyl (meth)acrylate,

[0041] Amino group-containing (meth)acrylic monomers such as dimethylaminoethyl (meth)acrylate and diethylaminoethyl (meth)acrylate, Examples include polyfunctional (meth)acrylic monomers such as diethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, neopentyl glycol di(meth)acrylate, and trimethylolpropane tri(meth)acrylate. Note that "(meth)acrylic" refers to at least one selected from "acrylic" and "methacrylic".

[0042] Conventional methods known as these can be used to make vinyl resin aqueous, and are not particularly limited. Examples include using an ethylenically unsaturated monomer having an acidic group as the ethylenically unsaturated monomer and neutralizing the acidic group after polymerization, using an unsaturated monomer having a hydrophilic group, or using an emulsifier. It is preferable to use a method that introduces and neutralizes an acidic group into the vinyl resin. Examples of neutralizing agents used to neutralize acidic groups include lithium hydroxide, sodium hydroxide, potassium hydroxide, ammonia, and various amines.

[0043] When introducing an acid group into a vinyl resin using an ethylenically unsaturated monomer having an acid group, the acid value of the vinyl resin can be adjusted as appropriate considering the discharge stability, but as an example, it is preferable to have an acid value of 10 mg KOH / g or more and 60 mg KOH / g or less. The acid value of an aqueous resin may be calculated from the constituent units of the aqueous resin, or it may be measured experimentally. An example of an experimental measurement method is to use a potentiometric automatic titrator to titrate the sample solution with a potassium hydroxide ethanol solution (0.1 mol / L), and after the titration is complete, calculate the acid value from the amount of ethanol solution added until the endpoint is reached.

[0044] It is preferable that the ethylenically unsaturated monomer contains an ethylenically unsaturated monomer having a hydroxyl group, as this results in the vinyl resin having a hydroxyl group, which reacts with isocyanate, a component of the adhesive, when forming the adhesive layer described later, thereby improving the adhesion between the printed layer and the adhesive layer. When introducing hydroxyl groups into a vinyl resin using an ethylenically unsaturated monomer having hydroxyl groups, the hydroxyl value of the vinyl resin can be adjusted as appropriate considering discharge stability, drying properties, laminate strength, etc., but as an example, it is preferable to have a value of 3 mg KOH / g or more and 50 mg KOH / g or less.

[0045] The hydroxyl value of aqueous resins can be calculated from each constituent unit of the aqueous resin, similar to the acid value, or it can be measured experimentally. An example of an experimental measurement method is to add an acetylation reagent (25% by mass pyridine solution of acetic anhydride) to the sample, heat to acetylate, allow to cool, add water to hydrolyze the acetic anhydride, then add ethanol as a solvent, and titrate the sample solution with a potassium hydroxide ethanol solution (0.5 mol / L) using a potentiometric automatic titrator similar to the one used for acid value. After the titration is complete, the hydroxyl value is calculated from the amount of ethanol solution added until the endpoint is reached.

[0046] Because of its excellent discharge stability, it is also preferable to include a styrene monomer as the ethylenically unsaturated monomer.

[0047] The weight-average molecular weight of the vinyl resin can be adjusted as appropriate, taking into consideration factors such as discharge stability, blocking resistance, and adhesive strength, but as an example, it is preferably between 2,000 and 200,000.

[0048] Examples of vinyl resins include acrylic resins such as acrylic acid-acrylic acid ester copolymers; styrene-acrylic resins such as styrene-acrylic acid copolymers, styrene-methacrylic acid copolymers, styrene-methacrylic acid-acrylic acid ester copolymers, styrene-α-methylstyrene-acrylic acid copolymers, and styrene-α-methylstyrene-acrylic acid-acrylic acid ester copolymers; styrene-maleic acid copolymers, styrene-maleic anhydride copolymers, vinylnaphthalene-acrylic acid copolymers, and the like.

[0049] Urethane resins can be synthesized from polyhydric alcohols and polyisocyanates, and acid group-containing polyols, chain extenders, and reaction inhibitors can be used in combination as needed.

[0050] Polyhydric alcohols used in the synthesis of urethane resins include aliphatic diols such as ethylene glycol, diethylene glycol, propylene glycol, 1,3-propanediol, 1,2,2-trimethyl-1,3-propanediol, 2,2-dimethyl-3-isopropyl-1,3-propanediol, 1,4-butanediol, 1,3-butanediol, 3-methyl-1,3-butanediol, 1,5-pentanediol, 3-methyl-1,5-pentanediol, neopentyl glycol, 1,6-hexanediol, 1,4-bis(hydroxymethyl)cyclohesane, and 2,2,4-trimethyl-1,3-pentanediol;

[0051] Trimethylolethane, trimethylolpropane, glycerin, hexanetriol, pentaerythritol, and other trifunctional or more aliphatic polyols;

[0052] Polyether polyols obtained by ring-opening polymerization of aliphatic diols or polyols with various cyclic ether-containing compounds such as ethylene oxide, propylene oxide, tetrahydrofuran, ethyl glycidyl ether, propyl glycidyl ether, butyl glycidyl ether, phenyl glycidyl ether, and allyl glycidyl ether;

[0053] Examples include polyester polyols, which are reaction products of at least one selected from the aliphatic diols, aliphatic polyols, and polyether polyols mentioned above with a polycarboxylic acid. One or more of these can be used in combination. Polycarboxylic acids used in the synthesis of polyester polyols include aliphatic dicarboxylic acids such as succinic acid, adipic acid, azelaic acid, sebacic acid, dodecanedicarboxylic acid, maleic anhydride, fumaric acid, 1,3-cyclopentanedicarboxylic acid, and 1,4-cyclohexanedicarboxylic acid; Aromatic dicarboxylic acids such as orthophthalic acid, isophthalic acid, terephthalic acid, 1,4-naphthalenedicarboxylic acid, 2,5-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, naphthalic acid, biphenyldicarboxylic acid, and 1,2-bis(phenoxy)ethane-p,p'-dicarboxylic acid; and anhydrides or ester-forming derivatives of these aliphatic or dicarboxylic acids; Examples include p-hydroxybenzoic acid, p-(2-hydroxyethoxy)benzoic acid and ester-forming derivatives of their dihydroxycarboxylic acids, and polybasic acids such as dimer acids, which can be used individually or in combination of two or more.

[0054] Polyisocyanates used in the synthesis of urethane resins include aromatic diisocyanates such as phenylenediisocyanate, tolylenediisocyanate, diphenylmethanediisocyanate, and naphthalenediisocyanate, as well as aliphatic or aliphatic cyclic structure-containing diisocyanates such as hexamethylenediisocyanate, lysinediisocyanate, cyclohexanediisocyanate, isophoronediisocyanate, dicyclohexylmethanediisocyanate, xylylenediisocyanate, and tetramethylxylylenediisocyanate, which can be used alone or in combination of two or more.

[0055] Examples of acid group-containing polyols include hydroxycarboxylic acids such as dimethylolpropionic acid, dimethylolbutanoic acid, citric acid, and malic acid, as well as carboxyl group-containing aliphatic polyols obtained by reacting a lower polyol with succinic acid, adipic acid, etc., such as succinic acid, and adipic acid, in such a way that two hydroxyl groups and one or more carboxyl groups remain in the molecule; and carboxyl group-containing aromatic polyols obtained by reacting a lower polyol with phthalic acid, trimellitic acid, pyromellitic acid, or their anhydrides, in such a way that two hydroxyl groups and one or more carboxyl groups remain in the molecule.

[0056] Chain elongators include diamines such as ethylenediamine, 1,2-propanediamine, 1,6-hexamethylenediamine, piperazine, 2,5-dimethylpiperazine, isophoronediamine, 4,4'-dicyclohexylmethanediamine, 3,3'-dimethyl-4,4'-dicyclohexylmethanediamine, and 1,4-cyclohexanediamine; N-hydroxymethylaminoethylamine, N-hydroxyethylaminoethylamine, N-hydroxypropylaminopropylamine, N-ethylaminoethylamine, and N-methylaminopropyl Examples include propylamine; diethylenetriamine, dipropylenetriamine, triethylenetetramine; hydrazine, N,N'-dimethylhydrazine, 1,6-hexamethylenebishydrazine; succinate dihydrazide, adipic acid dihydrazide, glutarate dihydrazide, sebacate dihydrazide, isophthalate dihydrazide; β-semicarbazide propionate hydrazide, 3-semicarbazide-propylcarbasic acid ester, semicarbazide-3-semicarbazidemethyl-3,5,5-trimethylcyclohexane, etc.

[0057] Reaction inhibitors include alkylamines such as n-propylamine, n-butylamine, and N,N-di-n-butylamine; alkanolamines such as monoethanolamine and diethanolamine; hydrazines such as hydrazine, alkyldihydrazine, and alkyldihydrazide; and monoalcohols such as methanol and ethanol.

[0058] Examples of methods for producing urethane resin include reacting a polyhydric alcohol, a polyisocyanate, and an acid group-containing polyol together to form urethane; reacting a polyhydric alcohol and a polyisocyanate under conditions that result in an excess of isocyanate groups, followed by the reaction with an acid group-containing polyol; reacting a polyhydric alcohol and a polyisocyanate under conditions that result in an excess of isocyanate groups, followed by the reaction with an acid group-containing polyol and a chain extender under conditions that result in an excess of isocyanate groups, and then the reaction with a reaction stopper; and reacting a polyhydric alcohol and a polyisocyanate under conditions that result in an excess of isocyanate groups, followed by the reaction of an acid group-containing polyol, a chain extender, and a reaction stopper together.

[0059] Conventional known methods can be used to make urethane resin aqueous, and are not particularly limited. Examples include a method in which an acid group-containing polyol is used as a raw material for the urethane resin to introduce an acid group into the urethane resin and neutralize the acid group after polymerization, a method in which a compound having a hydrophilic group is used as a raw material for the urethane resin, or a method in which an emulsifier is used. It is preferable to use a method in which an acid group is introduced into the urethane resin and then neutralized. Examples of neutralizing agents used to neutralize acidic groups include lithium hydroxide, sodium hydroxide, potassium hydroxide, ammonia, and various amines.

[0060] The acid value of the urethane resin can be adjusted as appropriate, taking into consideration factors such as discharge stability, but one example is between 5 mg KOH / g and 100 mg KOH / g.

[0061] The weight-average molecular weight of the urethane resin can be adjusted as appropriate, taking into consideration factors such as discharge stability, but as an example, it is between 2,000 and 100,000.

[0062] Water-based resins may be used alone, or two or more resins with different roles may be used in combination. For example, one resin may have parts with excellent affinity for pigments and parts with excellent affinity for water-based solvents, and may play the role of dispersing pigments in the water-based solvent (also called a pigment dispersion resin), while another resin may play the role of adhering to the substrate after the water-based solvent dries (also called a binder resin). When using two or more resins in combination, for example, vinyl resin and urethane resin may be used in combination, or two or more types of vinyl resins may be used in combination, or two or more types of urethane resins may be used in combination.

[0063] A pigment dispersion resin, which plays the role of dispersing pigments in an aqueous solvent, may be partially crosslinked with a crosslinking agent. Any crosslinking agent well known for such applications can be used without particular limitations.

[0064] The content of the aqueous resin can be adjusted as appropriate depending on the viscosity behavior, the components used in combination, and the desired ink properties, but as an example, it is 1% to 20% by mass of the total amount of printing ink.

[0065] Examples of aqueous solvents include water or aqueous organic solvents, which may be used alone or in combination of two or more. In this specification, an aqueous organic solvent refers to one that dissolves in 100 ml of water at 25°C in quantities of 10 ml or more. Examples of such aqueous solvents include polyhydric alcohols such as 1,2-ethanediol, 1,2-propanediol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, 1,2-pentanediol, 1,5-pentanediol, 1,2-hexanediol, 2,2-dimethyl-1,3-propanediol, 2-methyl-1,3-propanediol, 2-ethyl-2-methyl-1,3-propanediol, 3-methyl-1,3-butanediol, 3-methyl-1,5-pentanediol, 2-methyl-2-propyl-1,3-propanediol, 2-methylpentane-2,4-diol, 2-ethyl-1,3-hexanediol, diethylene glycol, dipropylene glycol, and glycerin.

[0066] Glycol monoalkyl ethers such as diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monopropyl ether, diethylene glycol monobutyl ether, triethylene glycol monomethyl ether, triethylene glycol monoethyl ether, triethylene glycol monobutyl ether, tetraethylene glycol monomethyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monopropyl ether, dipropylene glycol monomethyl ether, dipropylene glycol monopropyl ether, dipropylene glycol monobutyl ether, tripropylene glycol monomethyl ether, etc.; glycol ethers such as diethylene glycol diethyl ether, diethylene glycol isopropyl methyl ether, diethylene glycol butyl methyl ether, triethylene glycol dimethyl ether, triethylene glycol butyl methyl ether, tetraethylene glycol dimethyl ether, etc.

[0067] Examples include cyclic amide compounds such as 2-pyrrolidone, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, N-vinyl-2-pyrrolidone, N-butyl-2-pyrrolidone, and 5-methyl-2-pyrrolidone.

[0068] Printing inks may also preferably contain surfactants. Suitable surfactants include siloxane-based, acetylene-based, acrylic-based, fluorine-based, and polyoxyalkylene alkyl ether-based surfactants. One or more types may be used in combination, and it is preferable to use at least one of a siloxane-based surfactant and an acetylene-based surfactant.

[0069] The amount of surfactant added can be adjusted as appropriate, but as an example, it is 0.05% to 5.0% by mass, and more preferably 0.1% to 3.0% by mass, relative to the total amount of printing ink.

[0070] Surfactants in printing inks play various roles, including ensuring the dispersion stability of pigments and preventing ink from bleeding.

[0071] Printing inks may contain components other than those listed above. Examples of such components include viscosity modifiers, defoamers, preservatives, fungicides, rust inhibitors, pH adjusters, infrared absorbers, ultraviolet absorbers, waxes, drying inhibitors, and penetrating agents.

[0072] The pigments in printing inks can be dispersed in an aqueous solvent using general-purpose pigment dispersants, pigment dispersion resins, or surfactants. Furthermore, when using self-dispersing pigments, they can be dispersed in an aqueous solvent without the need for general-purpose pigment dispersants, pigment dispersion resins, or surfactants.

[0073] As general-purpose pigment dispersants, for example, acrylic resins such as the aforementioned acrylic acid-acrylic acid ester copolymers; styrene-acrylic resins such as styrene-acrylic acid copolymers, styrene-methacrylic acid copolymers, styrene-methacrylic acid-acrylic acid ester copolymers, styrene-α-methylstyrene-acrylic acid copolymers, and styrene-α-methylstyrene-acrylic acid-acrylic acid ester copolymers; aqueous resins such as styrene-maleic acid copolymers, styrene-maleic anhydride copolymers, and vinylnaphthalene-acrylic acid copolymers, or their salts, polyvinyl alcohols, and polyvinylpyrrolidones may also be used. Commercially available products may also be used.

[0074] Printing ink may be manufactured by mixing all raw materials at once, but more efficiently, for example, a pigment dispersion can be prepared by pre-mixing and dispersing the pigment with a general-purpose pigment dispersant, a pigment dispersion resin, or a surfactant, and the aqueous solvent, and then additives such as the binder resin, drying inhibitor, penetrating agent, and surfactant are mixed into it. The mixing and dispersion method used to prepare the pigment dispersion is not particularly limited and can be any known dispersion method.

[0075] The viscosity of the printing ink can be adjusted as needed, but one example is 2.0 to 20.0 mPa·s. The pH of printing ink can be adjusted as needed, but one example is 7.0 to 11.0.

[0076] The printed layer is formed on the substrate by inkjet printing using printing inks as exemplified above. The printing ink may be used in a single color, or multiple color inks may be combined depending on the application. The combination of color inks is not particularly limited, but for example, a full-color image can be obtained by using three colors: cyan, magenta, and yellow. In addition to these three colors, black ink may also be used, or further color inks such as orange, green, and violet may be combined. By using white ink in combination, it is possible to provide opacity to the contents. Alternatively, clear ink that does not contain coloring components can be used in combination. When multiple color inks are used in combination, for example, after printing with printing inks of cyan, magenta, yellow, black, and other hues, a white underprint is applied to the entire surface with white ink.

[0077] The printed layer can be printed using either a single-pass or multi-pass printing method, but single-pass printing is preferred. A single-pass printing method involves scanning a stationary substrate with the inkjet head only once, or passing the substrate under a fixed inkjet head only once. The same ink is never printed again on top of the ink already printed on the substrate. In a multi-pass printing method, the inkjet head scans the substrate multiple times.

[0078] When printing using a single-pass printing method, the drop volume of printing ink can be adjusted as appropriate, but it is preferable to have a volume of 0.6 to 60 pL as an example. The thickness of the printed layer varies depending on the pattern being printed, but as an example, it is between 0.2 μm and 20 μm.

[0079] After printing, a step may be provided to heat the printing ink to accelerate drying and curing. There are no particular restrictions on the heating method, and conventionally known methods such as heat drying, hot air drying, infrared (e.g., wavelength 700nm to 2500nm) drying, microwave drying, and drum drying can be used. These methods can also be used in combination. Heating is preferably performed within 20 seconds after printing, and more preferably within 10 seconds.

[0080] Prior to the formation of the printed layer, it is preferable that the substrate is subjected to surface treatment such as corona treatment or plasma treatment.

[0081] Prior to the formation of the printed layer, it is also preferable that a primer layer be provided on the substrate. The primer layer is formed, for example, by applying a primer containing a water-soluble metal salt onto the substrate. Such a primer disrupts the dispersion state of the pigment contained in the printing ink that lands on the primer layer, causing it to aggregate, and / or insolubilizes the aqueous resin in an aqueous solvent, thereby thickening the printing ink. This prevents bleeding and color unevenness between ink droplets, improving print quality. Furthermore, improvements in the adhesion, blocking resistance, and lamination suitability of the printed material can also be expected.

[0082] The water-soluble metal salt preferably contains one or more selected from metal salts and cationic polymer compounds. It is preferable to use a metal salt, Ca 2+ Mg 2+ Zn 2+ , and Al 3+ It is preferable to include a salt of one or more polyvalent metal ions selected from the group consisting of the following. The content of the water-soluble metal salt is preferably 0.5 to 25% by mass, and more preferably 1 to 20% by mass, based on the total amount of primer.

[0083] The primer may contain, in addition to the water-soluble metal salt, an aqueous resin, an aqueous solvent, a surfactant, a pH adjuster, an antifoaming agent, a thickener, a preservative, and the like. The aqueous solvent, surfactant, pH adjuster, antifoaming agent, thickener, and preservative can be used in the same way as those exemplified for use in printing inks.

[0084] Examples of aqueous resins include chlorinated polyolefin emulsions, hydrazine derivatives, acrylic emulsions, vinyl acetate emulsions, etc., and one or more of these can be used in combination.

[0085] As a chlorinated polyolefin emulsion, polyolefin resin is chlorinated to produce chlorine Examples include chlorinated polyolefin resins that have been further emulsified using emulsifiers, etc. The chlorinated polyolefin emulsion may be acid-modified with (anhydride) maleic acid, etc., in which case a basic compound is added to the system before use. Examples of polyolefin resins include polypropylene resin and polyethylene resin, and the degree of chlorination (chlorine content) is preferably 1 to 40% by mass, and more preferably 10 to 30% by mass, relative to the total resin. Two or more types of chlorinated polyolefin emulsions may be used in combination. The content of the chlorinated polyolefin emulsion is not particularly limited, but as an example, it is preferably 0.5 to 10% by mass, and more preferably 1 to 5% by mass, in terms of solid content in the primer.

[0086] Examples of hydrazine derivatives include compounds represented by the following formula (1) (where n is an integer from 1 to 10), compounds represented by the following formula (2) (where m is an integer from 1 to 4), maleic acid dihydrazide, fumaric acid dihydrazide, itaconic acid dihydrazide, etc., and one or more of these can be used in combination. The content of the hydrazine derivative is not particularly limited, but as an example, it is preferably 0.5 to 10% by mass in the primer, and more preferably 1 to 5% by mass.

[0087] [ka]

[0088] [ka]

[0089] Examples of at least one emulsion selected from the group consisting of acrylic emulsions and vinyl acetate emulsions include acrylic copolymers, styrene-acrylic copolymers, acrylic-vinyl acetate copolymers, and acrylic-vinyl chloride copolymers, which are emulsified using basic compounds, emulsifiers, etc. Examples of usable vinyl acetate emulsions include vinyl acetate-vinyl alcohol copolymers, vinyl chloride-vinyl acetate copolymers, α-olefin-vinyl acetate copolymers, etc., obtained by saponifying vinyl acetate and a portion thereof, which are emulsified using emulsifiers, etc. It is more preferable that these have a glass transition temperature of 0 to 50°C.

[0090] A small amount selected from the group consisting of acrylic emulsions and vinyl acetate emulsions. The content of at least one type is not particularly limited, but it is preferably 0.5 to 10% by mass in solid terms, and more preferably 1 to 5% by mass, in the primer.

[0091] The primer can be applied using conventional coating equipment such as inkjet printers, roll coaters, bar coaters, spray coaters, and gravure coaters.

[0092] The first substrate, on which the printing layer is applied, is wound up and sent to a later process.

[0093] (adhesive layer) The adhesive layer is a layer that bonds the first substrate, on which the printed layer is provided, to the second substrate. The adhesive layer is provided by a two-component curing adhesive containing a polyisocyanate composition (X) and a polyol composition (Y).

[0094] The polyisocyanate composition (X) comprises a polyisocyanate compound (A) having multiple isocyanate groups. The polyisocyanate compound (A) is not particularly limited and includes aromatic diisocyanates, aromatic aliphatic diisocyanates, aliphatic diisocyanates, alicyclic diisocyanates, and biuret, nurate, adduct, allophanate, carbodiimide modified, uretdione modified forms of these diisocyanates, as well as urethane prepolymers obtained by reacting these polyisocyanates with polyols, etc. These can be used individually or in combination.

[0095] Examples of aromatic diisocyanates include, but are not limited to, 2,2'-diphenylmethane diisocyanate, 2,4'-diphenylmethane diisocyanate, 4,4'-diphenylmethane diisocyanate, polymethylene polyphenyl polyisocyanate (also called polymeric MDI or crude MDI), 1,3-phenylenediisocyanate, 4,4'-diphenyl diisocyanate, 1,4-phenylenediisocyanate, 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, 4,4'-toluidine diisocyanate, 2,4,6-triisocyanate toluene, 1,3,5-triisocyanate benzene, dianisidine diisocyanate, 4,4'-diphenyl ether diisocyanate, and 4,4',4"-triphenylmethane triisocyanate.

[0096] 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).

[0097] Examples of aliphatic diisocyanates include trimethylene diisocyanate, tetramethylene diisocyanate, hexamethylene diisocyanate (also known as HDI), pentamethylene diisocyanate, 1,2-propylene diisocyanate, 2,3-butylene diisocyanate, 1,3-butylene diisocyanate, dodecamethylene diisocyanate, and 2,4,4-trimethylhexamethylene diisocyanate, but are not limited to these.

[0098] 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'-methylenebis(cyclohexyl isocyanate), and 1,4-bis(isocyanate-methyl)cyclohexane.

[0099] Examples of low molecular weight polyols used in the synthesis of adducts, or high molecular weight polyols used in the synthesis of urethane prepolymers, include alkylene 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, 1,4-cyclohexanediol, and 1,4-cyclohexanedimethanol;

[0100] Bisphenols such as bisphenol A, bisphenol F, hydrogenated bisphenol A, and hydrogenated bisphenol F; Dimer All; Bishydroxyethoxybenzene; Diethylene glycol, triethylene glycol, other polyethylene glycols, polypropylene glycol, polybutylene glycol, and other polyalkylene glycols; Polyalkylene glycols further increased in molecular weight with aromatic or aliphatic polyisocyanates, resulting in urethane-bonded polyether polyols;

[0101] A polyester polyol obtained by reacting the above-mentioned alkylene glycol or polyalkylene glycol with at least one aliphatic dicarboxylic acid having 2 to 13 carbon atoms, such as oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, fumaric acid, maleic acid, suberic acid, azelaic acid, sebacic acid, undecanediic acid, dodecanediic acid, and tridecanediic acid, or an aromatic polycarboxylic acid such as orthophthalic acid, isophthalic acid, terephthalic acid, trimellitic acid, and pyromellitic acid; Examples include polyester polyols, which are reaction products of polyesters obtained by ring-opening polymerization reactions of cyclic ester compounds such as propiolactone, butyrolactone, ε-caprolactone, σ-valerolactone, and β-methyl-σ-valerolactone with polyhydric alcohols such as glycol, glycerin, trimethylolpropane, and pentaerythritol.

[0102] The isocyanate composition (X) preferably has a viscosity of 300 mPa·s to 10,000 mPa·s at 50°C, and more preferably 450 mPa·s to 8,000 mPa·s. The viscosity of the polyisocyanate composition (X) in this application was determined using a rotational viscometer with a cone-plate of 1° and a diameter of 50 mm, and a shear rate of 100 sec. -1 The values ​​were measured at 50°C ± 1°C. The viscosity of the isocyanate composition (X) can be adjusted by the polyisocyanate compound (A) used and its amount.

[0103] The polyol composition (Y) contains a polyol (B) having multiple hydroxyl groups. Examples of polyol (B) include polyether polyol (B1), polyester polyol (B2), vegetable oil polyol (B3), polyurethane polyol (B4), etc., and can be used individually or in combination.

[0104] Examples of polyether polyols (B1) 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. It is preferable to use polypropylene polyols.

[0105] Polyester polyols (B2) are reaction products of polyhydric alcohols and polyhydric carboxylic acids. The polyhydric alcohol used in the synthesis of polyester polyols (B2) may be a diol or a polyol with three or more functionalities. Examples of diols include aliphatic diols such as ethylene glycol, diethylene glycol, propylene glycol, 1,3-propanediol, 1,2,2-trimethyl-1,3-propanediol, 2,2-dimethyl-3-isopropyl-1,3-propanediol, 1,4-butanediol, 1,3-butanediol, 3-methyl-1,3-butanediol, 1,5-pentanediol, 3-methyl-1,5-pentanediol, neopentyl glycol, 1,6-hexanediol, 1,4-bis(hydroxymethyl)cyclohesane, and 2,2,4-trimethyl-1,3-pentanediol.

[0106] Ether glycols such as polyoxyethylene glycol and polyoxypropylene glycol; Modified polyetherdiols obtained by ring-opening polymerization of aliphatic diols with various cyclic ether-containing compounds such as ethylene oxide, propylene oxide, tetrahydrofuran, ethyl glycidyl ether, propyl glycidyl ether, butyl glycidyl ether, phenyl glycidyl ether, and allyl glycidyl ether;

[0107] Lactone-based polyester polyols obtained by polycondensation reactions of aliphatic diols with various lactones such as lactanoides and ε-caprolactone;

[0108] Bisphenols such as bisphenol A and bisphenol F;

[0109] Examples include alkylene oxide adducts of bisphenols obtained by adding ethylene oxide, propylene oxide, etc., to bisphenols such as bisphenol A and bisphenol F.

[0110] Polyols with three or more functions include aliphatic polyols such as trimethylolethane, trimethylolpropane, glycerin, hexanetriol, and pentaerythritol;

[0111] Modified polyether polyols obtained by ring-opening polymerization of aliphatic polyols with various cyclic ether-containing compounds such as ethylene oxide, propylene oxide, tetrahydrofuran, ethyl glycidyl ether, propyl glycidyl ether, butyl glycidyl ether, phenyl glycidyl ether, and allyl glycidyl ether;

[0112] Examples include lactone-based polyester polyols obtained by polycondensation reactions between aliphatic polyols and various lactones such as ε-caprolactone.

[0113] Polycarboxylic acids used in the synthesis of polyester polyol (B2) include aliphatic dicarboxylic acids such as succinic acid, adipic acid, azelaic acid, sebacic acid, dodecanedicarboxylic acid, maleic anhydride, fumaric acid, 1,3-cyclopentanedicarboxylic acid, and 1,4-cyclohexanedicarboxylic acid; aromatic dicarboxylic acids such as orthophthalic acid, isophthalic acid, terephthalic acid, 1,4-naphthalenedicarboxylic acid, 2,5-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, naphthalic acid, biphenyldicarboxylic acid, and 1,2-bis(phenoxy)ethane-p,p'-dicarboxylic acid; anhydrides or ester-forming derivatives of these aliphatic or dicarboxylic acids; and polybasic acids such as p-hydroxybenzoic acid, p-(2-hydroxyethoxy)benzoic acid and ester-forming derivatives of these dihydroxycarboxylic acids, and dimer acids.

[0114] Examples of vegetable oil polyols (B3) 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.

[0115] Polyurethane polyols (B4) are reaction products of low-molecular-weight or high-molecular-weight polyols and polyisocyanates. As low-molecular-weight polyols, those similar to the polyhydric alcohols exemplified as raw materials for polyester polyols (B2) can be used. Examples of high-molecular-weight polyols include polyether polyols (B1) and polyester polyols (B2). As polyisocyanates, those similar to those used for polyisocyanates (A) can be used.

[0116] The polyol (B) preferably contains at least one of the following: polyether polyol (B1), polyester polyol (B2), and vegetable oil polyol (B3).

[0117] The number-average molecular weight of polyol (B) is not particularly limited, but is preferably between 300 and 4000 as an example. The number-average molecular weight used herein is the value measured by gel permeation chromatography (GPC) under the following conditions.

[0118] Measuring device: HLC-8320GPC, manufactured by Tosoh Corporation. Columns; manufactured by Tosoh Corporation: TSKgel 4000HXL, TSKgel 3000HXL, TSKgel 2000HXL, TSKgel 1000HXL Detector; RI (Differential Refractometer) Data processing; Tosoh Corporation Multi-Station GPC-8020 model II Measurement conditions: Column temperature 40°C Solvent: tetrahydrofuran Flow rate 0.35ml / min Standard; monodisperse polystyrene Sample: 100 μl of a tetrahydrofuran solution containing 0.2% by mass (based on resin solids content) filtered through a microfilter.

[0119] The polyol composition (Y) may also preferably contain a non-aromatic amine compound (C) having one or more amino groups. In this specification, an amino group means an NH2 group or an NHR group (where R is an alkyl group or aryl group which may have a functional group).

[0120] As the amine compound (C), 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,

[0121] 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,

[0122] Amine compounds (C1) having multiple amino groups, such as bis(aminomethyl)cyclohexane, diaminodicyclohexylmethane, isophoronediamine, mensendiamine, bis(cyanoethyl)diethylenetriamine, 1,4-bis-(8-aminopropyl)-piperazine, 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.

[0123] Primary or secondary alkanolamines (C2) such as monoethanolamine, monoisopropanolamine, monobutanolamine, N-methylethanolamine, N-ethylethanolamine, N-methylpropanolamine, diethanolamine, and diisopropanolamine,

[0124] Examples include primary or secondary amines (C3) such as ethylamine, octylamine, laurylamine, myristylamine, stearylamine, oleylamine, diethylamine, dibutylamine, and distearylamine.

[0125] The amount of amine compound (C) is preferably adjusted so that the amine value of the polyol composition (Y) is between 1 mg KOH / g and 100 mg KOH / g, and more preferably between 20 mg KOH / g and 80 mg KOH / g.

[0126] 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, and there are no particular restrictions; it can be calculated using known methods. If the chemical structure of amine compound (C) 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 amine compound (C) is unknown, it can be measured according to known amine value measurement methods, for example, JIS K7237-1995.

[0127] The polyol composition (Y) may further contain a monool compound (D) having one alcoholic hydroxyl group. The main chain of the monool compound (D) is not particularly limited and examples include vinyl resins, acrylic resins, polyesters, epoxy resins, urethane resins, etc., all having one hydroxyl group. Aliphatic alcohols, alkylalkylene glycols, etc., can also be used. The main chain of the monool compound (D) 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.

[0128] Specific examples of such monool compounds (D) 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.

[0129] 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.

[0130] Aromatic aliphatic monools such as benzyl alcohol,

[0131] 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.

[0132] The amount of monool compound (D) is adjusted as appropriate. When the adhesive used in the present invention contains monool compound (D), for example, it is 30% by mass or less of the total amount of the adhesive.

[0133] The polyol composition (Y) preferably has a viscosity of 50 mPa·s or more and 180 mPa·s or less at 50°C. The viscosity of the polyol composition (Y) can be adjusted by the polyol (B) skeleton or by plasticizers, etc., as described later. When adjusting with the polyol (B) skeleton, for example, the viscosity can be reduced by using polypropylene glycol or polyester polyols obtained by the reaction of aliphatic carboxylic acids with polyols. Alternatively, the viscosity can be increased by using polyester polyols obtained by the reaction of aromatic carboxylic acids with polyols.

[0134] The adhesive used in the present invention may contain components other than those described above. The 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 the polyol composition (Y) immediately before application of the adhesive. Examples of such components include catalysts, acid anhydrides, coupling agents, pigments, plasticizers, phosphoric acid compounds, and hydroxycarboxylic acids.

[0135] Examples of catalysts include metal catalysts, amine catalysts, and aliphatic cyclic amide compounds, and one or more of these can be used in combination. 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.

[0136] Examples of inorganic metal catalysts include those selected from Sn, Fe, Mn, Cu, Zr, Th, Ti, Al, Co, and the like.

[0137] 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.

[0138] 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.

[0139] 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.

[0140] It is preferable to use an organometallic catalyst, and it is preferable to use at least one selected from organozinc compounds, organotin compounds, and organobismuth compounds, with organotin compounds being preferable. The amount of organometallic catalyst is preferably 0.005% by mass or more and 1.0% by mass or less of the total amount of adhesive. If the organometallic catalyst is an organozinc compound, the amount is preferably 0.05% by mass or more and 1.0% by mass or less of the total amount of adhesive. If the organometallic catalyst is an organotin compound, the amount is preferably 0.005% by mass or more and 0.5% by mass or less of the total amount of adhesive. If the organometallic catalyst is an organobismuth compound, the amount is preferably 0.05% by mass or more and 1.0% by mass or less of the total amount of adhesive.

[0141] Examples of acid anhydrides include cyclic aliphatic acid anhydrides, aromatic acid anhydrides, and unsaturated carboxylic acid anhydrides, and one or more can be used in combination. More specifically, for example, phthalic anhydrides, trimellitic anhydrides, pyromellitic anhydrides, benzophenonetetracarboxylic anhydrides, dodecenyl succinic anhydrides, polyadipic anhydrides, polyazelaic anhydrides, polysebacic anhydrides, poly(ethyloctadecanediic acid) anhydrides, poly(phenylhexadecanedioic acid) anhydrides, tetrahydrophthalic anhydrides, methyltetrahydrophthalic anhydrides, methylhexahydrophthalic anhydrides, hexahydrophthalic anhydrides, methylhymic anhydrides, trialkyltetrahydrophthalic anhydrides, Examples include 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, and 1-methyl-dicarboxy-1,2,3,4-tetrahydro-1-naphthalenesuccinic acid dianhydride.

[0142] Furthermore, the above-mentioned compounds modified with glycol may be used as acid anhydrides. 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. Moreover, copolymer polyether glycols of two or more of these glycols and / or polyether glycols may also be used.

[0143] Examples of coupling agents include silane coupling agents, titanate-based coupling agents, and aluminum-based coupling agents.

[0144] Examples of silane coupling agents include aminosilanes such as γ-aminopropyltriethoxysilane, γ-aminopropyltrimethoxysilane, N-β(aminoethyl)-γ-aminopropyltrimethoxysilane, N-β(aminoethyl)-γ-aminopropyltrimethyldimethoxysilane, and N-phenyl-γ-aminopropyltrimethoxysilane; epoxysilanes such as β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, and γ-glycidoxypropyltriethoxysilane; vinylsilanes such as vinyltris(β-methoxyethoxy)silane, vinyltriethoxysilane, vinyltrimethoxysilane, and γ-methacryloxypropyltrimethoxysilane; and hexamethyldisilazane and γ-mercaptopropyltrimethoxysilane.

[0145] 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.

[0146] Examples of aluminum-based coupling agents include acetalkoxyaluminum diisopropylate.

[0147] 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).

[0148] 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.

[0149] 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.

[0150] 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.

[0151] Examples of plastic pigments include "Grandeur PP-1000" and "PP-2000S" manufactured by DIC Corporation.

[0152] 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.

[0153] 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 polyol composition (X) and the polyisocyanate composition (Y), and is more preferably 10 to 300 parts by mass to improve adhesion and blocking resistance.

[0154] 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.

[0155] 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.

[0156] 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.

[0157] 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.

[0158] 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.

[0159] 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.

[0160] 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.

[0161] Examples of polyester-based plasticizers include adipic acid-based polyesters, sebaciate-based polyesters, and phthalate-based polyesters.

[0162] Examples of carbonate-based plasticizers include propylene carbonate and ethylene carbonate.

[0163] 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.

[0164] 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.

[0165] It is also preferable to include at least one selected from the group consisting of 2,2-dimethylolacetic acid, 2,2-dimethylolpropionic acid, 2,2-dimethylolbutanoic acid, and 2,2-dimethylolpentanoic acid, as this provides good adhesion to the metal substrate. The amount of hydroxycarboxylic acid is preferably 0.1% by mass or more, more preferably 0.5% by mass or more, preferably 10% by mass or less, and more preferably 2.5% by mass or less of the polyol composition (Y).

[0166] The adhesive used in the present invention is solvent-free. In this specification, "solvent-free" adhesive refers to an adhesive whose 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 which 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.

[0167] The adhesive used in the present invention is preferably formulated such that the ratio of the number of moles [NCO] of isocyanate groups contained in the polyisocyanate composition (X) to the amount of molars of active hydrogen groups (hydroxyl groups or amino groups) contained in the polyol composition (Y), [NCO] / [OH+NH], is 1.0 to 3.0. This makes it possible to obtain appropriate curing properties regardless of the ambient humidity during coating.

[0168] (laminate) Next, the first substrate on which the printed layer is provided and the second substrate are bonded together using the adhesive described above to obtain a laminate. The laminating apparatus 1 used in the laminate manufacturing method of the present invention comprises a first coating section 10, a second coating section 20, and a laminator 30. The first coating section 10 comprises a first unwinding section 11 for dispensing a first substrate W1 on which the above-mentioned printed layer is provided, and a first coating apparatus 12 for coating the first substrate W1 dispensed from the first unwinding section 11 with one of the above-mentioned polyisocyanate composition (X) and polyol composition (Y). The second coating section 20 comprises a second unwinding section 21 for dispensing a second substrate W2, and a second coating apparatus 22 for coating the second substrate W2 dispensed from the second unwinding section 21 with the composition of the above-mentioned polyisocyanate composition (X) and polyol composition (Y) that was not coated on the first substrate W1. Hereinafter, among the polyisocyanate composition (X) and polyol composition (Y), the composition coated by the first coating apparatus 12 will be referred to as the first coating agent, and the composition coated by the second coating apparatus 22 will be referred to as the second coating agent. The first coating agent is, for example, the polyisocyanate composition (X), and the second coating agent is, for example, the polyol composition (Y). The first substrate W1 is rotatably mounted on the first unwinding section 11, and the second substrate W2 is rotatably mounted on the second unwinding section 21.

[0169] The first coating apparatus 12 and the second coating apparatus 22 can each be equipped with various coating devices such as a spray coater, direct gravure coater, (micro) chamber doctor coater, gravure kiss reverse coater, offset gravure coater, bar coater, roll kiss coater, reverse roll coater, slot die coater, air doctor coater, forward rotation roll coater, blade coater, knife coater, vacuum die coater, spin coater, and dipping coater. The following description will focus on the case where a roll coater is used as the first coating apparatus 11 and an offset gravure coater is used as the second coating apparatus 21.

[0170] Figure 2 is a schematic diagram showing the main parts of the first coating apparatus 12. As shown in Figure 2, the first coating apparatus 12 is a four-roll squeeze-roll type roll coater and includes an application roll 121, a doctor roll 122, a metering roll 123, a coating roll 124, a backing roll 125, and a cooling roll 126. These rolls are arranged so that their rotation axes are parallel to each other. The area opposite the application roll 121 and the doctor roll 122 is the liquid reservoir 120, from which the first coating agent is supplied from a supply device (not shown). Weir plates 127 are positioned at both ends of the liquid reservoir 120.

[0171] Roll coaters can be of the gap type or nip type, and both can be used as preferred. When the roll coater is a gap type, the outer surface of the application roll 121 and the outer surface of the doctor roll 122 are positioned with a small gap of 50 to 200 μm. For example, by adjusting this gap, the amount of the first coating agent applied to the first substrate W1 can be adjusted. When the roll coater is a gap type, both the application roll 121 and the doctor roll 122 are rolls with outer surfaces made of metal (non-elastic material).

[0172] In a nip-type roll coater, the outer circumference of the application roll 121 is covered with an elastic material such as rubber, and one roll is pressed against the other roll and deformed. The contact area between the two rolls is called the nip, and the thickness and uniformity of the coating can be controlled as the coating passes through the nip. The nip type is preferable because it makes it easier to make the amount of the first coating applied in the width direction of the first substrate W1 (the direction intersecting the conveying direction of the first substrate W1) more uniform.

[0173] The weir plate 127 is positioned to prevent the first coating agent from flowing down from both ends of the application roll 121 and doctor roll 122. The shape of the weir plate 127 can be adjusted as appropriate. Conventional known materials can be used as the material. A scraper may also be positioned outside the weir plate 127. The scraper scrapes off any first coating agent that has leaked beyond the weir plate 127.

[0174] The doctor roll 122 is equipped with a temperature control unit (not shown) to maintain the first coating agent stored in the liquid reservoir 120 at a constant temperature (e.g., 25-100°C) and stabilize its viscosity. As a result, the outer surface of the doctor roll 122 is kept at a constant temperature.

[0175] As shown in Figure 2, the application roll 121 and the doctor roll 122 rotate downward in the liquid reservoir 120, thereby applying the first coating agent to the outer surface of the doctor roll 122.

[0176] The metering roll 123 receives the first coating applied to the outer surface of the doctor roll 122. The outer surface of the metering roll 123 is made of an elastic material such as rubber and is pressed against the outer surface of the doctor roll 122. The metering roll 123 also functions as a roller that adjusts the application width of the first coating to match the first substrate W1.

[0177] The first composition applied to the outer surface of the metering roll 123 is transferred to the coating roll 124. The outer surface of the coating roll 124 is made of a metal material and is pressed against the outer surface of the metering roll 123. Similar to the doctor roll 122, it is preferable that the temperature of the outer surface of the coating roll 124 is kept constant by a temperature control unit (not shown). This stabilizes the viscosity of the first coating agent applied to the first substrate W1. The temperature of the outer surface of the coating roll 124 can be adjusted as appropriate, but as an example, it is 40°C to 90°C. 50°C to 80°C is preferred to reduce the inclusion of air bubbles when applying the first coating agent to the first substrate.

[0178] The backing roll 125 holds and conveys the first substrate W1 between itself and the coating roll 124, and assists in the transfer of the first composition applied to the outer surface of the coating roll 124 to the first substrate W1. The outer surface of the backing roll 125 is formed of an elastic material such as rubber.

[0179] It is preferable that the angle formed between the first substrate W1 before it passes between the coating roll 124 and the backing roll 125 and the first substrate W1 after it passes is set to be obtuse.

[0180] The cooling roll 126 is a roll with a cooling device (not shown) and its outer surface is made of metal. The cooling roll 126 is intended to prevent the backing roll 125 from overheating. The temperature of the outer surface of the cooling roll 126 is maintained at, for example, 15 to 35°C.

[0181] When the laminating device 1 starts operating, the first substrate W1 is fed from the first unwinding unit 11 to the first coating device 12, where each roll starts rotating. The first coating agent stored in the liquid reservoir 120 is applied to the surface of the doctor roll 122 by the rotation of the application roll 121 and doctor roll 122, and is then sequentially transferred to the metering roll 123 and coating roll 124. The first coating agent transferred to the coating roll 124 is transferred onto the printed layer printed on the first substrate W1, which is transported between the coating roll 124 and the backing roll 125. The first coating unit 12 then feeds the first substrate W1 coated with the first coating agent to the laminator 30.

[0182] At this time, the amount of the first coating applied to the first substrate W1 can be adjusted by varying the rotation speeds of the doctor roll 122, metering roll 123, and coating roll 124. For example, the rotation speeds are adjusted to decrease in the order of coating roll 124, metering roll 123, and doctor roll 122. The transport speed of the first substrate W1 can be, for example, 30 to 300 m / min, and preferably 100 to 250 m / min. The amount of the first coating applied is adjusted as appropriate, but is generally 0.3 to 3.0 g / m². 2 Preferably, and more preferably, 0.3 to 2.0 g / m² 2 That is the case.

[0183] Figure 3 is a schematic diagram showing the main parts of the second coating apparatus 22. The second coating apparatus 22 applies the second coating agent to the second substrate W2 delivered from the second unwinding section 21. The second coating apparatus 22 includes a gravure roll 221, an offset roll 222, a chamber doctor 223, an impression cylinder 224, a coating liquid tank 225, a pump 226, and a temperature controller 227.

[0184] The gravure roll 221 is a metal roll rotatably supported by the second coating apparatus 22 and rotationally driven by a drive device (not shown). Multiple recesses (gravure patterns) are formed on the surface of the gravure roll 221, for example, by laser engraving. The amount of coating liquid applied to the surface of the gravure roll 221 can be adjusted by changing the volume, aperture ratio, depth, etc. of these recesses. The gravure pattern applied to the surface of the gravure roll 121 is not particularly limited, but since continuous cell shapes such as diagonal lines tend to cause thickness unevenness, a hole-type pattern is preferably used. More preferably, a honeycomb pattern is used. As an example, the gravure pattern applied to the gravure roll 121 has a line count of 100 to 2000 lines / inch and a plate depth of 1 to 120 μm.

[0185] As shown in Figure 3, the chamber doctor 223 is a container comprising a storage section 223a for storing a second coating agent, a plate-shaped doctor blade 223b, a plate-shaped sealing plate 223c, and a pair of side plates 223d. The chamber doctor 223 is positioned radially to one side of the gravure roll 221 and opens toward the gravure roll 221. The storage section 223a is sealed by the doctor blade 223b, the sealing plate 223c, the pair of side plates 223d, and the gravure roll 221, and a portion of the outer surface of the gravure roll 221 is immersed in the second coating agent stored in the storage section 223a.

[0186] The doctor blade 223b protrudes from the upper end of the opening of the storage section 223a toward the gravure roll 221, and its tip is pressed against the outer circumferential surface of the gravure roll 221, sealing the downstream side of the storage section 223a in the direction of roll rotation. The doctor blade 223b scrapes off and measures excess second coating material adhering to the outer circumferential surface of the gravure roll 221 as the gravure roll 221 rotates. In this embodiment, the doctor blade 223b is installed so as to be in the opposite direction to the rotation direction of the gravure roll 221. This allows for more accurate measurement of the second coating material. The material of the doctor blade 223b is not particularly limited and may be metal such as stainless steel or resin.

[0187] The seal plate 223c protrudes from the lower end of the opening of the storage section 223a toward the gravure roll 221. The tip of the seal plate 223c is pressed against the outer circumferential surface of the gravure roll 221, sealing the upstream side of the storage section 223a in the direction of roll rotation. The material of the seal plate 223c is not particularly limited and may be, for example, a resin such as polyester.

[0188] The side plates 223d are attached to both sides of the chamber doctor 223, that is, to both ends in the rotation axis direction of the gravure roll 221. The side of the side plate 223d facing the gravure roll 221 has an arc shape that follows the gravure roll 221 and is pressed against the gravure roll 221.

[0189] The chamber doctor 223 may also be equipped with a temperature control means, separate from the temperature controller 227 described later, to heat the second coating liquid stored in the storage section 223a and maintain it at a constant temperature, for example, 20 to 60°C. This can further stabilize the viscosity of the second coating liquid during coating and improve the coating quality.

[0190] The offset roll 222 is a rubber roll that is rotatably supported on the second coating apparatus 22 so as to be parallel to the gravure roll 221 and is rotationally driven by a drive device (not shown). The offset roll 222 is positioned so as to be in contact with the outer surface of the gravure roll 221, and the second coating applied to the outer surface of the gravure roll 221 is transferred to it.

[0191] When applying a second coating agent to a second substrate W2 via a rubber offset roll 222, there is little risk of damaging the second substrate W2 (especially the vapor-deposited layer if the second substrate has one) even if there is a difference between the transport speed of the second substrate W1 and the peripheral speed of the offset roll 222. Therefore, it becomes possible to adjust the amount of the second coating agent applied to the second substrate W2 by adjusting the speed ratio of the gravure roll 221 to the transport speed of the second substrate W2 to 30-100%. Consequently, it becomes unnecessary to use multiple gravure rolls 222 with different line counts, and manufacturing costs can be reduced. The transport speed of the second substrate W2 is the same as the transport speed of the first substrate W1.

[0192] The diameter of the offset roll 222 is not particularly limited, but is, for example, 60 to 250 mm in diameter, preferably 60 to 200 mm, and more preferably 60 to 120 mm. The diameters of the gravure roll 221 and impression cylinder 224 are similar. Generally, a smaller diameter for the offset roll 222 is preferable because it reduces mist, but this may cause the offset roll 222 to bend. The diameter should be appropriately selected within a range that does not cause problems due to deformation of the offset roll 222.

[0193] Besides the arrangement shown in Figure 3, various configurations are possible for the gravure roll 221, offset roll 222, and impression cylinder 223. For example, as shown in Figure 4(A), the gravure roll 221, offset roll 222, and impression cylinder 224 may be arranged horizontally. Alternatively, as shown in Figure 4(B), the gravure roll 221 and offset roll 222 may be placed below the impression cylinder 224. Furthermore, by inverting Figure 4(B), the gravure roll 221 and offset roll 222 may be placed above the impression cylinder 224. Arranging them linearly so that they are sandwiched between the gravure roll 221 and the impression cylinder 224, as shown in Figure 3 and Figure 4(A), is preferable because it can suppress bending even if the diameter of the offset roll 222 is small.

[0194] In Figure 3, the gravure roll 221 is positioned to rotate from the bottom to the top of the chamber doctor 223, but this is not the only configuration. For example, as shown in Figure 4(C), the gravure roll 221 may be positioned to rotate from the top to the bottom of the chamber doctor 223. In this case, the doctor blade 223b is positioned below the chamber doctor 223, which is downstream in the direction of roll rotation.

[0195] The rotation direction of the gravure roll 221 may be either forward rotation, which is the same direction as the rotation direction of the offset roll 222 as shown in Figure 3, or reverse rotation, which is the opposite direction to the rotation direction of the offset roll 222. Similarly, the rotation direction of the offset roll 222 may be either forward rotation, which is the same direction as the conveying direction of the second substrate W2 as shown in Figure 3, or reverse rotation, which is the opposite direction to the conveying direction of the second substrate W2.

[0196] The impression cylinder 224 is a roll that clamps and conveys the second substrate W2 between itself and the offset roll 222. The impression cylinder 224 presses the second substrate W2 against the offset roll 222, transferring the second coating applied to the outer surface of the offset roll 222 to the second substrate W2. The material of the impression cylinder 224 is not particularly limited, and for example, rubber or metal can be used. If the transferability of the second coating is to be improved, it should be made of rubber, and if the tension control of the second substrate W2 is to be made easier and the bending of the roll is to be suppressed, it should be made of metal such as aluminum or iron, or carbon. The surface treatment can be selected from chrome plating, ceramic, etc., taking into consideration the coating conditions.

[0197] The impression cylinder 224 may be equipped with a drive device (not shown). The drive device may be used to rotate the impression cylinder 224 and adjust the speed ratio between the offset roll 222 and the impression cylinder 224. This allows for adjustment of the appearance of the surface coated with the second coating liquid.

[0198] The coating liquid tank 225 is a container for storing the second coating agent. As shown in Figure 3, the coating liquid tank 225 is connected via piping to a pump 226 that flows the second coating agent into the chamber doctor 223. The coating liquid tank 225 is also connected to the chamber doctor 223 via piping, and any second coating agent that overflows from the storage section 223a of the chamber doctor 223 is collected in the coating liquid tank 225.

[0199] Pump 226 is connected via piping to the coating liquid tank 225 and the chamber doctor 223, and supplies the second coating agent stored in the coating liquid tank 225 to the storage section 223a of the chamber doctor 223. Pump 226 can be, for example, a sine pump, or any pump capable of handling the second coating agent which has been heated for temperature control.

[0200] The temperature regulator 227 adjusts the temperature of the second coating agent stored in the coating liquid tank 225 to, for example, 20 to 60°C. Thereby, the temperature of the second coating agent is kept constant, and the viscosity of the second coating agent is stabilized to a viscosity suitable for coating. Further, since the second coating device 22 according to the present embodiment includes a sealed chamber doctor 223, the temperature and viscosity of the second coating agent can be further stabilized. The temperature regulator 227 is, for example, a water temperature regulator that heats water, which is a heat medium, with a heater and circulates it around the second coating agent stored in the coating liquid tank 225.

[0201] Either one or both of the path through which the second coating agent flows into the chamber doctor 223 and the path through which the second coating agent overflowing from the storage portion 223a of the chamber doctor 223 is recovered into the coating liquid tank 225 may be provided with degassing means (not shown). Examples of the degassing means include a hollow fiber membrane module, a centrifugal degassing device, an ultrasonic degassing device, and the like. Thereby, the amount of bubbles in the second coating agent can be reduced, and streaks and entrainment of bubbles during coating can be suppressed.

[0202] The pipe connecting the coating liquid tank 225 and the chamber doctor 223 and the pipe connecting the pump 226 and the chamber doctor 223 may each be provided with means for adjusting the temperature of the pipe. Thereby, the viscosity of the second coating agent can be further stabilized, and the coating quality can be improved.

[0203] When the operation of the laminating device 1 is started, the second base material W2 is sent from the second unwinding portion 21 to the second coating device 22, and each roll starts to rotate in the second coating device 22. The second coating agent stored in the chamber doctor 223 is transferred to the second base material W2 via the gravure roll 221 and the offset roll 222. The coating amount of the second coating agent transferred to the second base material W2 is appropriately adjusted according to the purpose, but 0.3 to 3.0 g / m 2 is preferable, and more preferably 0.3 to 2.0 g / m 2 is used. The second coating section 22 sends the first base material W2 coated with the second coating agent to the laminator 30.

[0204] The laminator 30 includes a bonding section 31 and a winding section 32. Figure 5 is a schematic diagram showing the main parts of the bonding section 31. As shown in Figure 5, the bonding section 31 includes a pair of laminating rolls 311 and 312, a cooling roll 313, and a backing roll 314. One of the laminating rolls 311 and 312, for example, laminating roll 311, has a metal outer surface, while the other, for example, laminating roll 312, has an elastic material such as rubber on its outer surface, and one roll is pressed against the other roll and deformed.

[0205] The first substrate W1, delivered from the first coating section 12, and the second substrate W2, delivered from the second coating section 22, pass between two opposing laminating rolls 311 and 312 with the coated surfaces of the first and second coating liquids in contact. The pressure from the two laminating rolls 311 and 312 causes the first substrate W1 and the second substrate W2 to bond together. This initiates the reaction between the first and second coating liquids.

[0206] The two laminate rolls 311 and 312 are kept from being excessively heated by the heat from the adhesives (first coating agent and second coating agent) by a temperature control unit (not shown) that maintains a constant temperature on their outer surfaces. It is preferable that the temperature of the outer surfaces be set to 40 to 80°C, more preferably 40 to 60°C. The pressure applied from the two laminate rolls 311 and 312 to the first substrate W1 and the second substrate W2 is, for example, 0.05 to 0.5 MPa.

[0207] The cooling roll 313 is equipped with a cooling device (not shown) and its outer surface is made of metal. The laminate that has passed between the two laminating rolls 311 and 312 is conveyed through 313 to the winding section 32. The temperature of the outer surface of the cooling roll 126 is maintained at, for example, 15 to 35°C.

[0208] The backing roll 314 is positioned so that its outer surface is in contact with the outer surface of the laminating roll 312. The backing roll 314 also presses the laminating roll 312 against the laminating roll 311. The outer surface of the backing roll 314 is made of an elastic material such as rubber.

[0209] The winding section 32 winds up the laminate formed by bonding the first base material W1 and the second base material W2 at the bonding section 31. The wound laminate is stored (aged) at room temperature (25°C) to 50°C for 3 to 72 hours. By appropriately selecting and setting the aging conditions, the adhesive hardens sufficiently and the practical properties of the adhesive layer are achieved.

[0210] In Figure 1, the laminator 30 is positioned between the first coating section 10 and the second coating section 20, but this is not limited to this arrangement. The second coating section 20 may be positioned between the first coating section 10 and the laminator 30, or the first coating section 10 may be positioned between the second coating section 20 and the laminator 30. By optimizing the layout of each part, the laminating device 1 can be miniaturized.

[0211] The laminating apparatus 1 applies the amount of the first coating agent (g / m²) between the first coating section 10 and the laminator 30. 2 The device may be equipped with a measuring device to measure the amount of the second coating agent applied, and a measuring device may be provided between the second coating section 20 and the laminator 30 to measure the amount of the second coating agent applied. A measuring device may be provided between the bonding section 31 and the winding section 32 to measure the total amount of the first and second coating agents applied. Conventional measuring devices can be used for these devices, for example, an infrared spectrophotometer. Alternatively, a means for measuring the weight of the first coating agent (or second coating agent) applied within a certain period may be provided separately, and the amount of the first coating agent (or second coating agent) applied may be calculated by dividing the weight by the area of ​​the first substrate W1 to which the first coating agent (or second coating agent) was applied within that period.

[0212] If the laminating device 1 is equipped with means for measuring the application amount of the first coating agent and the second coating agent, by linking it with controllers that control the rotation speed of each roll of the first coating device 12 and the second coating device 22, the rotation speed of each roll can be controlled based on the measured application amount, thereby maintaining the application amounts of the first coating agent and the second coating agent at predetermined appropriate values, and the physical properties of the adhesive can be made suitable.

[0213] In the above description, the first coating agent is described as containing a polyisocyanate composition (X), i.e., a polyisocyanate compound (A), but does not contain compounds having active hydrogen groups such as a polyol compound (B) or an amine compound (C), and the second coating agent is described as containing a polyol composition (Y), i.e., a polyol compound (B) and an amine compound (C), but does not contain a polyisocyanate compound (A). However, the explanation is not limited to these examples. The second coating agent may further contain either or both a monool compound (D) and a catalyst. Alternatively, the first coating agent may contain either or both a polyol compound (B) and a monool compound (D) in addition to the polyisocyanate compound (A).

[0214] In all embodiments, the second coating agent does not contain polyisocyanate compound (A). When an inorganic filler is used, if the first coating agent contains a compound having an active hydrogen group, it may be included in either the first or second coating agent. If the first coating agent does not contain a compound having an active hydrogen group, it is added to the second coating agent. It goes without saying that these coating agents may appropriately contain each component of the adhesive described above. These first and second coating agents are combined as appropriate depending on the purpose.

[0215] The laminate produced in this manner may be further bonded to other substrates. Known methods for laminating other substrates may be used, such as dry lamination, non-solvent lamination, heat lamination, heat sealing, or extrusion lamination, or a method having a two-component fractional coating process may be used. The adhesive used in this process may or may not be that of the present invention. Other substrates similar to those described above can be used.

[0216] <Laminate> Examples of the structure of a laminate produced by the manufacturing method of the present invention include: (1) Substrate 1 / Printing layer / Adhesive layer 1 / Sealant film (2) Substrate 1 / Printing layer / Adhesive layer 1 / Metal vapor deposition unstretched film (3) Substrate 1 / Printing layer / Adhesive layer 1 / Metal vapor-deposited stretched film (4) Transparent vapor-deposited stretched film / Printed layer / Adhesive layer 1 / Sealant film (5) Substrate 1 / Printing layer / Adhesive layer 1 / Substrate 2 / Adhesive layer 2 / Sealant film (6) Substrate 1 / Printing layer / Adhesive layer 1 / Metal vapor-deposited stretched film / Adhesive layer 2 / Sealant film (7) Substrate 1 / Printing layer / Adhesive layer 1 / Transparent vapor-deposited stretched film / Adhesive layer 2 / Sealant film (8) Substrate 1 / Printing layer / Adhesive layer 1 / Metal layer / Adhesive layer 2 / Sealant film (9) Substrate 1 / Printing layer / Adhesive layer 1 / Substrate 2 / Adhesive layer 2 / Metal layer / Adhesive layer 3 / Sealant film (10) Substrate 1 / Printing layer / 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.

[0217] Examples of substrate 1 used in composition (1) include MDOPE film, OPE film, OPP film, PET film, nylon film, and paper. Alternatively, a substrate 1 coated for purposes such as improving gas barrier properties may be used. Commercially available coated substrate films 1 include K-OPP film and K-PET film. The printing layer and adhesive layer 1 are as described above. Examples of sealant films include CPP film, LLDPE film, and gas barrier heat-seal film.

[0218] Examples of substrates 1 used in components (2) and (3) include MDOPE film, OPE film, OPP film, PET film, and paper. The printing layer and adhesive layer 1 are as described above. 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 such as aluminum. Examples of stretched metal-deposited films include VM-MDOPE film, VM-OPE film, and VM-OPP film, which are MDOPE film, OPE film, and OPP film with metal deposition such as aluminum.

[0219] Examples of transparent vapor-deposited stretched films used in configuration (4) include MDOPE film, OPE film, OPP film, PET film, nylon film, 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 printing layer and adhesive layer 1 are as described above. The sealant film is the same as that used in configuration (1).

[0220] Examples of substrate 1 used in composition (5) include PET film and paper. Examples of substrate 2 include nylon film. The printing layer and adhesive layer 1 are as described above. The sealant film is the same as that used in composition (1).

[0221] The base material 1 of composition (6) is the same as that of compositions (2) and (3). Examples of metal-deposited stretched films include VM-MDOPE film, VM-OPE film, VM-OPP film, and VM-PET film, which are obtained by depositing metal such as aluminum onto MDOPE film, OPE film, OPP film, or PET film. The printing layer and adhesive layer 1 are as described above. The sealant film is the same as that of composition (1).

[0222] Examples of the substrate 1 in composition (7) include PET film and paper. Examples of the transparent vapor-deposited stretched film include those the same as in composition (4). The printing layer and adhesive layer 1 are as described above. Examples of the sealant film include those the same as in composition (1).

[0223] Examples of the base material 1 in composition (8) include PET film and paper. Examples of the metal layer include aluminum foil. The printing layer and adhesive layer 1 are as described above. Examples of the sealant film are the same as those in composition (1).

[0224] 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. The printing layer and adhesive layer 1 are as described above. Examples of sealant film are the same as those in configuration (1).

[0225] <Packaging material> The laminate described above can be suitably used as packaging material, particularly as packaging material for food packaging. The packaging material is formed by molding the laminate described above into a bag shape and heat-sealing it. Various forms of packaging material exist, such as three-sided sealed bags, four-sided sealed bags, gusseted bags, pillow bags, bottomed containers with a bell-top design, Tetra Classic, Brück type, tube containers, paper cups, and lids. The packaging material may also be provided with an easy-open treatment or resealing mechanism as appropriate.

[0226] The packaging material of the present invention can be suitably used not only for food applications but also as a packaging material for filling detergents and pharmaceuticals. Specific applications include laundry liquid detergents, dishwashing liquid detergents, bath liquid detergents, bath liquid soaps, liquid shampoos, liquid conditioners, and pharmaceutical tablets. It can also be used as a secondary packaging material for packaging the above-mentioned containers.

Claims

1. A method for manufacturing a laminate comprising a first substrate, a printed layer, an adhesive layer which is a cured coating film of a two-component curable adhesive containing a polyol composition (X) and a polyisocyanate composition (Y), and a second substrate, arranged in this order, A step of applying a printed layer to the first substrate by inkjet printing, The process involves applying a first coating agent onto the printed layer, The process involves applying a second coating agent onto a second substrate, The process includes a step of bonding the first substrate and the second substrate together such that the first coating agent and the second coating agent come into contact with each other, A method for producing a laminate, wherein the first coating agent comprises one of the polyol composition (X) and the polyisocyanate composition (Y), and the second coating agent comprises the other of the polyol composition (X) and the polyisocyanate composition (Y).

2. The method for manufacturing a laminate according to claim 1, wherein the first substrate is subjected to corona treatment or plasma treatment prior to the step of providing the printed layer.

3. The method for manufacturing a laminate according to claim 1, wherein a primer layer is provided on the first substrate prior to the step of providing the printed layer.

4. The method for producing a laminate according to claim 1, wherein the first coating agent comprises a polyisocyanate composition (Y).

5. A laminate manufactured by the method for manufacturing a laminate according to any one of claims 1 to 4.

6. A packaging material obtained by forming a bag from the laminate described in claim 5.

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