Laminate

Abstract

In the polyurethane dispersion in which a polyurethane resin is dispersed in water, the polyurethane resin is a reaction product obtained by reacting at least a polyisocyanate component with an active hydrogen group-containing component, the polyisocyanate component contains a polyisocyanate compound having a carbon ring and at least one isocyanate group directly bonded to the carbon ring in a proportion of 90 mass% or more relative to the total amount of the polyisocyanate component, and the active hydrogen group-containing component contains a diol having 2 to 4 carbon atoms and an active hydrogen group-containing compound having a hydrophilic group.

Description

[Technical field]

[0001] The present invention relates to polyurethane dispersions and laminates. [Background technology]

[0002] Conventionally, films made of polyvinylidene chloride or vinylidene chloride copolymer (hereinafter abbreviated as PVDC) have been known as films with excellent oxygen gas barrier properties, but PVDC generates harmful gases when burned.

[0003] For this reason, films made of polyvinyl alcohol or ethylene-vinyl alcohol copolymers have been used, but the gas barrier properties of these films are sometimes insufficient.

[0004] In view of this, a laminate has been proposed as a film having excellent gas barrier properties, which includes a substrate such as a resin film and a polyurethane layer obtained by applying a polyurethane dispersion onto the substrate and drying it.

[0005] The polyurethane dispersion is, for example, a polyurethane dispersion in which a polyurethane resin obtained by reacting an isocyanate group-terminated prepolymer with a chain extender is dispersed in water. More specifically, a polyurethane dispersion has been proposed in which the isocyanate group-terminated prepolymer is obtained by at least reacting a polyisocyanate component containing xylylene diisocyanate and / or hydrogenated xylylene diisocyanate with a polyol component containing a diol having 2 to 6 carbon atoms, a low molecular weight polyol having a valence of 3 or more, and an active hydrogen group-containing compound containing a hydrophilic group, the chain extender contains a primary amino group or an alkoxysilyl compound having a primary amino group and a secondary amino group, and the molar ratio of hydroxyl groups in the low molecular weight polyol having a valence of 3 or more to the total molar ratio of hydroxyl groups in the polyol component is less than 25%. It has also been proposed that a deposition film in which a metal oxide is deposited on a plastic film is used as the substrate in the laminate, and a polyurethane layer is laminated on the metal deposition layer (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0006] [Patent Document 1] JP 2017-222863 A Summary of the Invention [Problem to be solved by the invention]

[0007] On the other hand, such laminates are required to maintain excellent gas barrier properties even after high-temperature sterilization (retort treatment) depending on the application.

[0008] However, when the polyurethane layer described in Patent Document 1 is laminated on a metal vapor deposition film, the polyurethane layer may deform and deteriorate (whiten, expand, etc.) when the resulting laminate is subjected to high-temperature sterilization treatment (retort treatment), and the metal vapor deposition layer may be damaged depending on the deformation, etc. As a result, the above laminate may not be able to obtain sufficient gas barrier properties after high-temperature sterilization treatment (retort treatment).

[0009] The present invention relates to a polyurethane dispersion that can give a laminate that has excellent gas barrier properties even after high-temperature sterilization (retort treatment), and a laminate obtained by using the polyurethane dispersion. [Means for solving the problem]

[0010] The present invention [1] provides a polyurethane dispersion in which a polyurethane resin is dispersed in water, the polyurethane resin being a reaction product of at least a polyisocyanate component and an active hydrogen group-containing component, the polyisocyanate component containing a polyisocyanate compound having a carbon ring and at least one isocyanate group directly bonded to the carbon ring in a proportion of 90 mass% or more based on the total amount of the polyisocyanate component, and the active hydrogen group-containing component containing a diol having 2 to 4 carbon atoms, and an active hydrogen group-containing compound containing a hydrophilic group.

[0011] The present invention [2] includes the polyurethane dispersion according to the above [1], in which the polyisocyanate compound contains isophorone diisocyanate.

[0012] The present invention [3] further includes the polyurethane dispersion according to the above [1] or [2], which contains a crosslinking agent.

[0013] The present invention [4] includes a laminate comprising a first polyurethane layer containing a dried product of the polyurethane dispersion described in any one of the above [1] to [3], and an inorganic layer arranged so as to be in contact with at least one surface of the first polyurethane layer.

[0014] The present invention [5] includes the laminate according to the above [4], in which the inorganic layer contains aluminum oxide and / or silicon oxide.

[0015] The present invention [6] further comprises the laminate according to the above [4] or [5], further comprising a second polyurethane layer on the surface of the first polyurethane layer opposite the surface in contact with the inorganic layer, the second polyurethane resin being a reaction product of at least a second polyisocyanate component containing xylylene diisocyanate and / or hydrogenated xylylene diisocyanate, and a second active hydrogen group-containing component containing a diol having 2 to 4 carbon atoms, and an active hydrogen group-containing compound having a hydrophilic group. Effect of the Invention

[0016] In the polyurethane dispersion of the present invention, the active hydrogen group-containing component contains a diol having 2 to 4 carbon atoms, and an active hydrogen group-containing compound that contains a hydrophilic group.

[0017] A polyurethane dispersion obtained by using such an active hydrogen group-containing component can provide a polyurethane layer having excellent gas barrier properties.

[0018] Furthermore, in the polyurethane dispersion of the present invention, the polyisocyanate component contains a polyisocyanate compound having a carbon ring and an isocyanate group directly bonded to the carbon ring in a proportion of 90 mass % or more based on the total amount of the polyisocyanate component.

[0019] In such polyurethane dispersions, since an isocyanate group is directly bonded to a carbon ring in the polyisocyanate component, the degree of freedom of the isocyanate group and the degree of freedom of the urethane bond in the polyurethane resin are limited.

[0020] As a result, deformation and deterioration of the polyurethane layer due to high-temperature sterilization treatment (retort treatment) can be suppressed, and even if the polyurethane layer is laminated on the inorganic layer, damage to the inorganic layer can be suppressed.

[0021] Furthermore, in the laminate of the present invention, since the dried product of the above-mentioned polyurethane dispersion is laminated onto the inorganic layer, deformation and deterioration of the polyurethane layer due to high-temperature sterilization treatment (retort treatment) can be suppressed, and the laminate maintains excellent gas barrier properties even after high-temperature sterilization treatment (retort treatment). [Brief description of the drawings]

[0022] [Figure 1] FIG. 1 is a schematic diagram showing an embodiment of the laminate of the present invention. [Diagram 2] FIG. 2 is a schematic diagram showing another embodiment of the laminate of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0023] The polyurethane dispersion of the present invention can be obtained by dispersing a polyurethane resin (aqueous polyurethane resin) in water.

[0024] The polyurethane resin is a reaction product obtained by reacting at least a polyisocyanate component with an active hydrogen group-containing component.

[0025] The polyisocyanate component contains a polyisocyanate compound as a main component (for example, at a ratio of 90% by mass or more, preferably 95% by mass or more, based on the total amount of the polyisocyanate component).

[0026] Preferably, the polyisocyanate component consists of a polyisocyanate compound.

[0027] A polyisocyanate compound is an organic compound having two or more isocyanate groups.

[0028] As the polyisocyanate compound, preferably, an organic compound having two isocyanate groups (diisocyanate compound) is used.

[0029] The polyisocyanate compound contains, as an essential component, a polyisocyanate compound having a carbon ring and at least one isocyanate (-NCO) group directly bonded to the carbon ring (hereinafter, referred to as a "carbon ring-directly bonded NCO compound").

[0030] That is, the polyisocyanate component contains a polyisocyanate compound, and the polyisocyanate compound contains an NCO compound directly bonded to a carbon ring as an essential component.

[0031] In other words, the polyisocyanate component contains NCO compounds directly attached to a carbon ring.

[0032] The carbocyclic NCO compound is an organic compound having a carbocyclic ring and two or more isocyanate groups, and further, at least one of the two or more isocyanate groups is directly bonded to the carbocyclic ring.

[0033] The NCO compound directly bonded to a carbon ring is preferably a diisocyanate compound having a carbon ring and two isocyanate groups, and further, at least one of the two isocyanate groups is directly bonded to the carbon ring.

[0034] In the carbocyclic ring-directly bonded NCO compound, the carbocyclic ring is a cyclic hydrocarbon group, and examples thereof include an aromatic ring, an alicyclic ring, and an unsaturated carbocyclic ring.

[0035] More specific examples of the carbocyclic ring include aromatic rings such as a benzene ring, alicyclic rings such as a cyclopentane ring and a cyclohexane ring, and unsaturated carbocyclic rings such as a cyclohexene ring.

[0036] The number of these carbocyclic rings contained in one molecule of the carbocyclic ring-directly-bonded NCO compound may be singular (one) or plural (two or more).

[0037] In addition, when the number of carbocycles contained in one molecule of the carbocycle-directly-bonded NCO compound is multiple, the carbocycle may be a polycyclic carbocycle in which multiple carbocycles are condensed to share one side, or a multiple carbocycle in which a bridged ring is formed between any carbons in the carbocycle. More specifically, such a carbocycle may be an aromatic polycyclic carbocycle such as a naphthalene ring, or an alicyclic multiple carbocycle such as a norbornene ring.

[0038] The number of carbon rings contained in one molecule of the carbocyclic NCO compound is preferably singular (one).

[0039] In a carbocyclic NCO compound, an isocyanate group directly bonded to a carbocyclic ring refers to an isocyanate (-NCO) group in which the nitrogen atom is single-bonded to a carbon atom constituting the carbocyclic ring.

[0040] When the NCO compound directly bonded to a carbocyclic ring has two or more carbocyclic rings, it is sufficient that at least one isocyanate group is directly bonded to at least one of the carbocyclic rings.

[0041] In other words, the NCO compound directly bonded to a carbocyclic ring is sufficient as long as it contains a carbocyclic ring to which at least one isocyanate group is directly bonded, and may contain a carbocyclic ring to which no isocyanate group is bonded, or a carbocyclic ring to which an isocyanate group is indirectly bonded (e.g., via an alkylene group, an arylene group, etc.), or may contain an isocyanate group that is not directly bonded to a carbocyclic ring.

[0042] More specifically, examples of the NCO compound directly bonded to a carbon ring include NCO compound monomers directly bonded to a carbon ring, such as aromatic polyisocyanates having an aromatic ring to which an isocyanate group is directly bonded (aromatic ring-directly bonded NCO compound) and alicyclic polyisocyanates having an alicyclic ring to which an isocyanate group is directly bonded (alicyclic ring-directly bonded NCO compound).

[0043] Examples of aromatic polyisocyanates include aromatic diisocyanates such as tolylene diisocyanate (2,4- or 2,6-tolylene diisocyanate or a mixture thereof) (TDI), phenylene diisocyanate (m-, p-phenylene diisocyanate or a mixture thereof), 1,5-naphthalene diisocyanate (NDI), 4,4'-diphenyl diisocyanate, diphenylmethane diisocyanate (4,4'-, 2,4'-, or 2,2'-diphenylmethane diisocyanate or a mixture thereof) (MDI), 4,4'-toluidine diisocyanate (TODI), and 4,4'-diphenyl ether diisocyanate.

[0044] Examples of alicyclic polyisocyanates include 1,3-cyclopentane diisocyanate, 1,3-cyclopentene diisocyanate, 1,4-cyclohexane diisocyanate, 1,3-cyclohexane diisocyanate, 3-isocyanatomethyl-3,5,5-trimethylcyclohexyl isocyanate (also known as isophorone diisocyanate) (IPDI), methylene bis(cyclohexyl isocyanate) (also known as bis(isocyanatocyclohexyl)methane) (4,4'-, 2,4'-, or 2,2'-methylene bis(cyclohexyl isocyanate) their trans,trans-isomer, trans,cis-isomer, cis,cis-isomer, or mixtures thereof) (H 12 alicyclic diisocyanates such as methylcyclohexane diisocyanate (methyl-2,4-cyclohexane diisocyanate, methyl-2,6-cyclohexane diisocyanate) and the like.

[0045] The NCO compound directly bonded to a carbocyclic ring also includes derivatives of the above monomers (NCO compound monomers directly bonded to a carbocyclic ring).

[0046] Examples of the derivatives of the above monomers include polymers of the above monomers (e.g., dimers, trimers (e.g., isocyanurate-modified products, iminooxadiazinedione-modified products), pentamers, heptamers, etc.), allophanate-modified products (e.g., allophanate-modified products produced by the reaction of the above monomers with low-molecular-weight polyols described below), polyol-modified products (e.g., polyol-modified products (alcohol adducts) produced by the reaction of the above monomers with low-molecular-weight polyols described below), biuret-modified products, Examples of the modified monomer include aryl groups (e.g., biuret modified monomers produced by the reaction of the above-mentioned monomers with water or amines), urea modified monomers (e.g., urea modified monomers produced by the reaction of the above-mentioned monomers with diamines), oxadiazinetrione modified monomers (e.g., oxadiazinetrione modified monomers produced by the reaction of the above-mentioned monomers with carbon dioxide), carbodiimide modified monomers (carbodiimide modified monomers produced by the decarboxylation condensation reaction of the above-mentioned monomers), uretdione modified monomers, and uretonimine modified monomers.

[0047] These derivatives can be used alone or in combination of two or more kinds.

[0048] These carbocyclic NCO compounds can be used alone or in combination of two or more kinds.

[0049] As the carbon ring directly bonded NCO compound, preferably, aromatic polyisocyanate and alicyclic polyisocyanate are used, more preferably, alicyclic polyisocyanate is used, and further preferably, isophorone diisocyanate (IPDI) is used.

[0050] In other words, the carbocyclic NCO compound preferably contains isophorone diisocyanate (IPDI).

[0051] The carbocyclic NCO compounds can also be classified according to the number of carbocyclic rings.

[0052] More specifically, examples of NCO compounds directly bonded to a carbocyclic ring include NCO compounds directly bonded to a carbocyclic ring having one carbocyclic ring (hereinafter, referred to as a single-carbocyclic ring-directed NCO compound) and NCO compounds directly bonded to a carbocyclic ring having multiple carbocyclic rings (hereinafter, referred to as a multiple-carbocyclic ring-directed NCO compound).

[0053] Examples of the NCO compound directly bonded to a single carbon ring include polyisocyanate compounds having one carbon ring, one isocyanate group directly bonded to the carbon ring, and the remaining isocyanate groups bonded to the carbon ring directly and / or via an alkylene group.

[0054] Specific examples of such NCO compounds directly bonded to a single carbon ring include polyisocyanate compounds having one aromatic ring, one isocyanate group directly bonded to the aromatic ring, and the remaining isocyanate groups directly bonded to the aromatic ring. More specific examples include tolylene diisocyanate (TDI), phenylene diisocyanate, etc.

[0055] In addition, examples of the NCO compound directly bonded to a single carbon ring include polyisocyanate compounds having one alicyclic ring, one isocyanate group directly bonded to the alicyclic ring, and the remaining isocyanate groups bonded to the alicyclic ring via alkylene groups. More specifically, examples of the polyisocyanate compounds include isophorone diisocyanate (IPDI).

[0056] These NCO compounds directly bonded to a single carbon ring can be used alone or in combination of two or more kinds.

[0057] As the single carbon ring directly bonded NCO compound, preferably, tolylene diisocyanate (TDI) and isophorone diisocyanate (IPDI) are used, and more preferably, isophorone diisocyanate (IPDI) is used.

[0058] On the other hand, examples of the NCO compound directly bonded to multiple carbon rings include polyisocyanate compounds having two or more carbon rings, one of the isocyanate groups directly bonded to one of the carbon rings, and the remaining isocyanate groups bonded to one of the carbon rings directly and / or via an alkylene group.

[0059] A specific example of such a multi-carbon ring directly-bonded NCO compound is a polyisocyanate compound having two aromatic rings, one of which isocyanate group is directly bonded to one of the aromatic rings, and the remaining isocyanate group is directly and / or via an alkylene group to one of the aromatic rings. More specifically, for example, diphenylmethane diisocyanate (MDI) can be mentioned.

[0060] Further, as the multiple carbon ring directly bonded NCO compound, specifically, there can be mentioned a polyisocyanate compound having two alicyclic rings, one of the isocyanate groups being directly bonded to one of the alicyclic rings, and the remaining isocyanate group being directly bonded to one of the alicyclic rings and / or via an alkylene group. More specifically, for example, methylenebis(cyclohexylisocyanate)(H 12 MDI) etc.

[0061] These polycarbonate ring-directed NCO compounds can be used alone or in combination of two or more kinds.

[0062] As the multi-carbon ring directly bonded NCO compound, preferred are diphenylmethane diisocyanate (MDI), methylene bis(cyclohexyl isocyanate) (H 12 MDI), and more preferably methylene bis(cyclohexyl isocyanate) (H 12 MDI) are examples.

[0063] These carbocyclic NCO compounds can be used alone or in combination of two or more kinds.

[0064] As the carbon ring-directed NCO compound, from the viewpoint of improving heat resistance, a single carbon ring-directed NCO compound (preferably TDI, IPDI) and a multiple carbon ring-directed NCO compound (preferably H 12 Use in combination with MDI is also recommended.

[0065] The ratio of these compounds to be used together is as follows: a single carbon ring directly bonded NCO compound (preferably TDI, IPDI) and a multiple carbon ring directly bonded NCO compound (preferably H 12 The amount of the single carbon ring directly bonded NCO compound (preferably TDI, IPDI) is, for example, 50 parts by mass or more, preferably 60 parts by mass or more, more preferably 70 parts by mass or more, and even more preferably 80 parts by mass or more, and for example, 95 parts by mass or less, preferably 90 parts by mass or less, based on 100 parts by mass of the total amount of the single carbon ring directly bonded NCO compound (preferably H 12 MDI) is, for example, 5 parts by mass or more, preferably 10 parts by mass or more, and for example, 50 parts by mass or less, preferably 40 parts by mass or less, more preferably 30 parts by mass or less, and even more preferably 20 parts by mass or less.

[0066] Furthermore, the polyisocyanate component may contain, in addition to the NCO compound directly bonded to a carbon ring, a polyisocyanate compound that does not have an isocyanate group directly bonded to a carbon ring (hereinafter, a non-NCO compound directly bonded to a carbon ring), as necessary.

[0067] Examples of the non-carbon ring directly bonded NCO compound include non-carbon ring directly bonded NCO compound monomers such as chain aliphatic polyisocyanates having no carbon ring (hereinafter referred to as chain NCO compounds) and carbocyclic indirectly bonded polyisocyanates having a carbon ring but no isocyanate group directly bonded to the carbon ring (hereinafter referred to as carbocyclic indirect NCO compounds).

[0068] Examples of the chain NCO compound include chain aliphatic diisocyanates such as trimethylene diisocyanate, 1,2-propylene diisocyanate, butylene diisocyanate (tetramethylene diisocyanate, 1,2-butylene diisocyanate, 2,3-butylene diisocyanate, 1,3-butylene diisocyanate), 1,5-pentamethylene diisocyanate (PDI), 1,6-hexamethylene diisocyanate (also known as hexamethylene diisocyanate) (HDI), 2,4,4- or 2,2,4-trimethylhexamethylene diisocyanate, and 2,6-diisocyanate methylcaprate.

[0069] Examples of the carbocyclic indirect NCO compounds include aromatic aliphatic diisocyanates in which an isocyanate group is indirectly bonded to an aromatic ring, such as xylylene diisocyanate (1,2-, 1,3-, or 1,4-xylylene diisocyanate or a mixture thereof (XDI)), tetramethyl xylylene diisocyanate (1,3- or 1,4-tetramethyl xylylene diisocyanate or a mixture thereof) (TMXDI), and ω,ω'-diisocyanato-1,4-diethylbenzene. Examples of such diisocyanates include alicyclic aliphatic diisocyanates in which an isocyanate group is indirectly bonded to an alicyclic ring, such as bis(isocyanatomethyl)cyclohexane (hydrogenated xylylene diisocyanate (1,2-, 1,3-, or 1,4-hydrogenated xylylene diisocyanate or a mixture thereof) (H6XDI) and norbornane diisocyanate (2,5- or 2,6-bis(isocyanatomethyl)bicyclo[2.2.1]heptane or a mixture thereof) (NBDI).

[0070] Non-carbocyclic direct NCO compounds also include derivatives of the same types as those mentioned above.

[0071] Examples of the derivatives include polymers of non-carbon ring-directed NCO compound monomers, allophanate-modified products, polyol-modified products, biuret-modified products, urea-modified products, oxadiazinetrione-modified products, carbodiimide-modified products, uretdione-modified products, and uretonimine-modified products.

[0072] The derivatives can be used alone or in combination of two or more kinds.

[0073] These non-carbocyclic directly bonded NCO compounds can be used alone or in combination of two or more kinds.

[0074] The content of the non-carbon ring directly bonded NCO compound is 10 mass % or less, preferably 5 mass % or less, more preferably 1 mass % or less, and even more preferably 0 mass % based on the total amount of the carbon ring directly bonded NCO compound and the non-carbon ring directly bonded NCO compound (total amount of the polyisocyanate compound).

[0075] In addition, the content of the NCO compounds directly bonded to a carbocyclic ring is 90% by mass or more, preferably 95% by mass or more, more preferably 99% by mass or more, and even more preferably 100% by mass, based on the total amount of the NCO compounds directly bonded to a carbocyclic ring and the NCO compounds directly bonded to a non-carbocyclic ring (total amount of the polyisocyanate compounds).

[0076] In other words, the polyisocyanate compound in the polyisocyanate component preferably comprises a carbon ring-directed NCO compound.

[0077] The content of the NCO compound directly bonded to a carbon ring is 90% by mass or more, preferably 95% by mass or more, and more preferably 99% by mass or more, based on the total amount of the polyisocyanate component.

[0078] On the other hand, the content of the non-carbon ring directly bonded NCO compound is 10 mass % or less, preferably 5 mass % or less, and more preferably 1 mass % or less, based on the total amount of the polyisocyanate component.

[0079] When the content ratio of the carbocyclic NCO compound and the non-carbocyclic NCO compound is within the above range, excellent resistance to high-temperature sterilization treatment (retort treatment) and gas barrier properties can be obtained.

[0080] The active hydrogen group-containing component may be a polyol component.

[0081] The polyol component contains, as essential components, a diol having 2 to 4 carbon atoms and an active hydrogen group-containing compound that contains a hydrophilic group.

[0082] The diol having 2 to 4 carbon atoms has a molecular weight (number average) of 40 or more and less than 300, preferably less than 400, and is an organic compound having 2 to 4 carbon atoms and two hydroxyl groups. Specific examples of the diol include alkanediols (alkylene glycols having 2 to 4 carbon atoms) such as ethylene glycol, propylene glycol, 1,3-propanediol, 1,4-butylene glycol, 1,3-butylene glycol, and 1,2-butylene glycol, ether diols having 2 to 4 carbon atoms such as diethylene glycol, and alkene diols having 2 to 4 carbon atoms such as 1,4-dihydroxy-2-butene.

[0083] These diols having 2 to 4 carbon atoms can be used alone or in combination of two or more kinds.

[0084] As the diol having 2 to 4 carbon atoms, from the viewpoint of gas barrier properties, preferably, an alkanediol having 2 to 4 carbon atoms, more preferably, ethylene glycol is used.

[0085] The mixing ratio of the diol having 2 to 4 carbon atoms per 100 parts by mass of the total amount of the polyol components is, for example, 20 parts by mass or more, preferably 30 parts by mass or more, and for example, 80 parts by mass or less, preferably 70 parts by mass or less.

[0086] The active hydrogen group-containing compound containing a hydrophilic group is a compound that contains a hydrophilic group such as a nonionic group or an ionic group and contains two or more active hydrogen groups such as amino groups or hydroxyl groups. Specific examples of the active hydrogen group-containing compound include a nonionic group-containing compound and an ionic group-containing compound.

[0087] Examples of the active hydrogen group-containing compound containing a nonionic group include polyoxyethylene glycol, one-end blocked polyoxyethylene glycol, and polyols containing polyoxyethylene side chains.

[0088] The polyol containing a polyoxyethylene side chain is an organic compound containing a polyoxyethylene group in the side chain and having two or more hydroxyl groups, and can be synthesized as follows.

[0089] That is, first, the above-mentioned diisocyanate and one-end-capped polyoxyethylene glycol (for example, an alkoxypolyoxyethylene monool one end of which is capped with an alkyl group having 1 to 4 carbon atoms and having a number average molecular weight of 200 to 6000, preferably 300 to 3000) are subjected to a urethane reaction at a ratio in which the isocyanate groups of the diisocyanate are in excess relative to the hydroxyl groups of the one-end-capped polyoxyethylene glycol, and if necessary, the unreacted diisocyanate is removed to obtain a polyoxyethylene chain-containing monoisocyanate.

[0090] Next, the polyoxyethylene chain-containing monoisocyanate and a dialkanolamine (eg, diethanolamine, etc.) are reacted to form a urea at a ratio such that the amount of the isocyanate group of the polyoxyethylene group-containing monoisocyanate is approximately equal to the amount of the secondary amino group of the dialkanolamine.

[0091] In the active hydrogen group-containing compound containing a nonionic group, the number average molecular weight of the nonionic group, specifically, the polyoxyethylene group, is, for example, 600 to 6,000.

[0092] As the diisocyanate for obtaining a polyol containing a polyoxyethylene side chain, preferably, an aliphatic diisocyanate such as hexamethylene diisocyanate (HDI), 1,4- or 1,3-bis(isocyanatomethyl)cyclohexane (H6XDI), 3-isocyanatomethyl-3,5,5-trimethylcyclohexyl isocyanate (also known as isophorone diisocyanate) (IPDI), 4,4'-methylenebis(cyclohexyl isocyanate) (H 12 Examples of suitable diisocyanates include alicyclic diisocyanates such as 2,6-bis(isocyanatomethyl)norbonane (NBDI).

[0093] The active hydrogen group-containing compound containing an ionic group is, for example, an organic compound having both an anionic group such as carboxylic acid or a cationic group such as a quaternary amine and two or more active hydrogen groups such as hydroxyl groups or amino groups, and preferably an organic compound having both an anionic group and two or more hydroxyl groups, and more preferably an organic compound having both a carboxylic acid and two hydroxyl groups (an active hydrogen group-containing compound containing a carboxy group (for example, a carboxy group-containing polyol, etc.)).

[0094] Examples of carboxy group-containing polyols include polyhydroxyalkanoates (dihydroxyalkanoates) such as 2,2-dimethylolacetic acid, 2,2-dimethylollactic acid, 2,2-dimethylolpropionic acid (also known as dimethylolpropionic acid), 2,2-dimethylolbutanoic acid, 2,2-dimethylolbutyric acid, and 2,2-dimethylolvaleric acid, and preferably 2,2-dimethylolpropionic acid.

[0095] These active hydrogen group-containing compounds containing a hydrophilic group can be used alone or in combination.

[0096] As the active hydrogen group-containing compound containing a hydrophilic group, preferably, an active hydrogen group-containing compound containing an ionic group is used, more preferably, a carboxy group-containing polyol is used, further preferably, a polyhydroxyalkanoic acid is used, and particularly preferably, a dihydroxyalkanoic acid is used.

[0097] By blending polyhydroxyalkanoic acid, it is possible to further improve the water dispersibility, gas barrier property, adhesion to the substrate, and transparency.

[0098] The mixing ratio of the active hydrogen group-containing compound that contains a hydrophilic group is, for example, 20 parts by mass or more, preferably 30 parts by mass or more, and for example, 50 parts by mass or less, preferably 45 parts by mass or less, relative to 100 parts by mass of the total amount of the polyol component.

[0099] The polyol component may further contain, as optional components, other low molecular weight polyols (low molecular weight polyols excluding diols having 2 to 4 carbon atoms and active hydrogen group-containing compounds containing hydrophilic groups) and high molecular weight polyols.

[0100] Other low molecular weight polyols include, for example, diols (dihydric alcohols) having 5 or more carbon atoms, and low molecular weight polyols having three or more hydric acids.

[0101] Examples of diols (dihydric alcohols) having 5 or more carbon atoms include alkanediols having 5 to 20 carbon atoms, such as 1,5-pentanediol, 1,6-hexanediol, neopentyl glycol, 3-methyl-1,5-pentanediol, and 1,3- or 1,4-cyclohexanediol; 2,6-dimethyl-1-octene-3,8-diol, 1,3- or 1,4-cyclohexanedimethanol, and mixtures thereof; hydrogenated bisphenol A, bisphenol A; and ether diols having 5 or more carbon atoms, such as triethylene glycol and dipropylene glycol.

[0102] Examples of diols (dihydric alcohols) having 5 or more carbon atoms include divalent polyalkylene oxides having a number average molecular weight of 400 or less. Such polyalkylene oxides can be obtained, for example, by addition reaction of alkylene oxides such as ethylene oxide and / or propylene oxide with the above-mentioned dihydric alcohols as an initiator, as polyethylene glycols (polyoxyethylene ether glycols), polypropylene glycols (polyoxypropylene ether glycols), polyethylene polypropylene glycols (random or block copolymers), etc. In addition, examples of polytetramethylene ether glycols having a number average molecular weight of 400 or less obtained by ring-opening polymerization of tetrahydrofuran, etc., can also be mentioned.

[0103] The trivalent or higher low molecular weight polyol has a number average molecular weight of 40 or more and less than 300, preferably less than 400, and is an organic compound having three or more hydroxyl groups in one molecule. Examples of such low molecular weight polyols include trivalent alcohols (low molecular weight triols) such as glycerin, 2-methyl-2-hydroxymethyl-1,3-propanediol, 2,4-dihydroxy-3-hydroxymethylpentane, 1,2,6-hexanetriol, trimethylolpropane, and 2,2-bis(hydroxymethyl)-3-butanol, tetravalent alcohols such as tetramethylolmethane (pentaerythritol) and diglycerin, pentavalent alcohols such as xylitol, hexavalent alcohols such as sorbitol, mannitol, allitol, iditol, dulcitol, altritol, inositol, and dipentaerythritol, heptavalent alcohols such as perseitol, and octavalent alcohols such as sucrose.

[0104] Examples of the trivalent or higher low molecular weight polyol include trivalent or higher polyalkylene oxides having a number average molecular weight of 40 or more and less than 300, preferably less than 400. Such polyalkylene oxides can be obtained as polyethylene polyols, polypropylene polyols, polyethylene polypropylene polyols (random or block copolymers), etc., by addition reaction of alkylene oxides such as ethylene oxide and / or propylene oxide with the above-mentioned trivalent or higher low molecular weight polyols or known polyamines as an initiator.

[0105] These trivalent or higher low molecular weight polyols can be used alone or in combination of two or more kinds.

[0106] As the trihydric or higher low molecular weight polyol, preferably, a trihydric alcohol (low molecular weight triol) or a tetrahydric alcohol is used, more preferably, a trihydric alcohol (low molecular weight triol) is used, and further preferably, trimethylolpropane or glycerin is used.

[0107] These other low molecular weight polyols (low molecular weight polyols excluding the above-mentioned diols having 2 to 4 carbon atoms and active hydrogen group-containing compounds containing a hydrophilic group) can be used alone or in combination of two or more kinds.

[0108] As the other low molecular weight polyol, preferably, a low molecular weight polyol having a valence of 3 or more is used, more preferably, a low molecular weight polyol having a valence of 3. When the polyol component contains a low molecular weight polyol having a valence of 3 or more (more preferably, a low molecular weight polyol having a valence of 3), the heat resistance can be improved in combination with the NCO compound directly bonded to the carbon ring.

[0109] When other low molecular weight polyols (low molecular weight polyols excluding the above-mentioned diols having 2 to 4 carbon atoms and the active hydrogen group-containing compounds containing hydrophilic groups) are contained, the content ratio thereof is, for example, 30 parts by mass or less, preferably 20 parts by mass or less, more preferably 10 parts by mass or less, and for example, 1 part by mass or more, relative to 100 parts by mass of the total amount of the polyol components.

[0110] Furthermore, when a trihydric or higher low-molecular-weight polyol is used as the other low-molecular-weight polyol, the combined ratio of the diol having 2 to 4 carbon atoms and the trihydric or higher low-molecular-weight polyol is, for example, 1 part by mass or more, preferably 5 parts by mass or more, and for example, 20 parts by mass or less, preferably 10 parts by mass or less, per 100 parts by mass of the total amount of the diol having 2 to 4 carbon atoms and the trihydric alcohol.

[0111] The high molecular weight polyol is a compound having two or more hydroxyl groups and a number average molecular weight (number average molecular weight measured by GPC using standard polystyrene as a calibration curve) of 300 or more, preferably 400 or more, and examples thereof include polyether polyols (e.g., polyoxyalkylene polyols, polytetramethylene ether polyols, etc.), polyester polyols (e.g., adipic acid-based polyester polyols, phthalic acid-based polyester polyols, lactone-based polyester polyols, etc.), polycarbonate polyols, polyurethane polyols (e.g., polyols obtained by urethane-modifying polyether polyols, polyester polyols, polycarbonate polyols, etc. with polyisocyanates), epoxy polyols, vegetable oil polyols, polyolefin polyols, acrylic polyols, vinyl monomer-modified polyols, etc.

[0112] These high molecular weight polyols can be used alone or in combination of two or more kinds.

[0113] In addition, if the high molecular weight polyol is contained in an excessive amount in the active hydrogen group-containing component, it causes a decrease in gas barrier properties, and therefore, from the viewpoint of suppressing the decrease in gas barrier properties, the content ratio of the high molecular weight polyol in the active hydrogen group-containing component is limited to a predetermined value or less.

[0114] More specifically, the content of high molecular weight polyol (i.e., high molecular weight polyol having a number average molecular weight of 300 or more) is 40 mass % or less, preferably 30 mass % or less, more preferably 20 mass % or less, even more preferably 10 mass % or less, still more preferably 5 mass % or less, and particularly preferably 2 mass % or less, based on the total amount of active hydrogen group-containing components.

[0115] In particular, when a high molecular weight polyol having a number average molecular weight of 1000 or more is contained in an active hydrogen group-containing component in excess, it significantly reduces the gas barrier properties. Therefore, from the viewpoint of suppressing the reduction in the gas barrier properties, the content of the high molecular weight polyol in the active hydrogen group-containing component is limited to a predetermined value or less.

[0116] More specifically, the content of the high molecular weight polyol having a number average molecular weight of 1000 or more is 40 mass % or less, preferably 30 mass % or less, more preferably 20 mass % or less, even more preferably 10 mass % or less, still more preferably 5 mass % or less, and particularly preferably 2 mass % or less, relative to the total amount of the active hydrogen group-containing component.

[0117] In other words, the active hydrogen group-containing component allows the inclusion of the high molecular weight polyol in the above-mentioned ratio.

[0118] From the viewpoint of gas barrier properties, the active hydrogen group-containing component (polyol component) preferably does not contain a high molecular weight polyol.

[0119] The polyol component more preferably comprises the above-mentioned diol having 2 to 4 carbon atoms, an active hydrogen group-containing compound containing a hydrophilic group, and a trivalent or higher low-molecular-weight polyol, or comprises a diol having 2 to 4 carbon atoms and an active hydrogen group-containing compound containing a hydrophilic group.

[0120] The active hydrogen group-containing component may further include an amino group-containing component in addition to the polyol component.

[0121] Examples of the amino group-containing component include amino group-containing compounds such as aromatic polyamines, araliphatic polyamines, alicyclic polyamines, aliphatic polyamines, amino alcohols, polyoxyethylene group-containing polyamines, primary amino groups, or alkoxysilyl compounds having primary amino groups and secondary amino groups (hereinafter sometimes referred to as amino group-containing alkoxysilyl compounds), hydrazine or derivatives thereof.

[0122] Examples of aromatic polyamines include 4,4'-diphenylmethanediamine and tolylenediamine.

[0123] Araliphatic polyamines include, for example, 1,3- or 1,4-xylylenediamine or mixtures thereof.

[0124] Examples of alicyclic polyamines include 3-aminomethyl-3,5,5-trimethylcyclohexylamine (also known as isophoronediamine), 4,4'-dicyclohexylmethanediamine, 2,5(2,6)-bis(aminomethyl)bicyclo[2.2.1]heptane, 1,4-cyclohexanediamine, 1-amino-3-aminomethyl-3,5,5-trimethylcyclohexane, bis-(4-aminocyclohexyl)methane, diaminocyclohexane, 3,9-bis(3-aminopropyl)-2,4,8,10-tetraoxaspiro[5,5]undecane, 1,3- and 1,4-bis(aminomethyl)cyclohexane, and mixtures thereof.

[0125] Examples of the aliphatic polyamine include ethylenediamine, propylenediamine, 1,3-propanediamine, 1,4-butanediamine, 1,5-pentanediamine, 1,6-hexamethylenediamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, 1,2-diaminoethane, 1,2-diaminopropane, and 1,3-diaminopentane.

[0126] Examples of amino alcohols include 2-((2-aminoethyl)amino)ethanol (also known as N-(2-aminoethyl)ethanolamine), 2-((2-aminoethyl)amino)-1-methylpropanol (also known as N-(2-aminoethyl)isopropanolamine), and the like.

[0127] Examples of polyoxyethylene group-containing polyamines include polyoxyalkylene ether diamines such as polyoxyethylene ether diamine. More specific examples include PEG#1000 diamine manufactured by Nippon Oil & Fats Co., Ltd., and Jeffamine ED-2003, EDR-148, and XTJ-512 manufactured by Huntsman Co., Ltd.

[0128] Examples of alkoxysilyl compounds having a primary amino group or a primary amino group and a secondary amino group (amino group-containing alkoxysilyl compounds) include alkoxysilyl compounds having a primary amino group such as γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, and N-phenyl-γ-aminopropyltrimethoxysilane; N-β(aminoethyl)γ-aminopropyltrimethoxysilane (also known as N-2-(aminoethyl)-3-aminopropyltrimethoxysilane); Examples of alkoxysilyl compounds having primary and secondary amino groups include N-β(aminoethyl)γ-aminopropyltriethoxysilane (also known as N-2-(aminoethyl)-3-aminopropyltriethoxysilane), N-β(aminoethyl)γ-aminopropylmethyldimethoxysilane (also known as N-2-(aminoethyl)-3-aminopropylmethyldimethoxysilane), and N-β(aminoethyl)γ-aminopropylmethyldiethoxysilane (also known as N-2-(aminoethyl)-3-aminopropylmethyldiethoxysilane).

[0129] Examples of hydrazine or its derivatives include hydrazine (including hydrates), succinic acid dihydrazide, and adipic acid dihydrazide.

[0130] These amino group-containing components can be used alone or in combination of two or more kinds.

[0131] As the amino group-containing component, preferably, an amino alcohol or an amino group-containing alkoxysilyl compound is used, and more preferably, 2-((2-aminoethyl)amino)ethanol (also known as N-(2-aminoethyl)ethanolamine) or N-β(aminoethyl)γ-aminopropyltrimethoxysilane (also known as N-2-(aminoethyl)-3-aminopropyltrimethoxysilane) is used.

[0132] As the amino group-containing component, more preferably, amino alcohol is used alone, and amino alcohol and amino group-containing alkoxysilyl compound are used in combination, and particularly preferably, amino alcohol and amino group-containing alkoxysilyl compound are used in combination.When these are used in combination, from the viewpoint of gas barrier property, the amino alcohol is, for example, 50 parts by mass or more, preferably 60 parts by mass or more, more preferably 70 parts by mass or more, and for example, 95 parts by mass or less, preferably 90 parts by mass or less, more preferably 85 parts by mass or less, based on the total amount of 100 parts by mass of amino alcohol and amino group-containing alkoxysilyl compound.In addition, the amino group-containing alkoxysilyl compound is, for example, 5 parts by mass or more, preferably 10 parts by mass or more, more preferably 15 parts by mass or more, and for example, 50 parts by mass or less, preferably 40 parts by mass or less, more preferably 30 parts by mass or less.

[0133] The amino group-containing component is preferably used as a chain extender in the prepolymer method described below.

[0134] When the active hydrogen group-containing component contains both a polyol component and an amino group-containing component, the content of the polyol component is, for example, 40 parts by mass or more, preferably 50 parts by mass or more, and, for example, 95 parts by mass or less, preferably 85 parts by mass or less, relative to 100 parts by mass of the total amount of the active hydrogen group-containing components. The content of the amino group-containing component is, for example, 5 parts by mass or more, preferably 15 parts by mass or more, and, for example, 60 parts by mass or less, preferably 50 parts by mass or less.

[0135] In the reaction between the polyisocyanate component and the active hydrogen group-containing component, a known method such as a one-shot method or a prepolymer method is used. Preferably, the prepolymer method is used.

[0136] In the one-shot method, for example, the above-mentioned components are formulated (mixed) so that the equivalent ratio (NCO / active hydrogen group) of the isocyanate group in the polyisocyanate component to the active hydrogen group (hydroxyl group, amino group) in the active hydrogen group-containing component is, for example, 0.8 or more, preferably 0.9 or more, for example, 1.2 or less, preferably 1.1 or less, and a curing reaction is carried out by a known polymerization method such as bulk polymerization (described later) or solution polymerization (described later) at, for example, room temperature to 250°C, preferably room temperature to 200°C, for example, 5 minutes to 72 hours, preferably 4 to 24 hours.

[0137] In the prepolymer method, first, a polyisocyanate component containing a carbon ring-directed NCO compound is reacted with at least a portion of the active hydrogen group-containing component (active hydrogen group-containing component (polyol component) other than a chain extender), preferably a diol having 2 to 4 carbon atoms, and an active hydrogen group-containing compound containing a hydrophilic group to synthesize an isocyanate group-terminated prepolymer.

[0138] In this reaction, the equivalent ratio (isocyanate group / active hydrogen group) of the isocyanate group in the polyisocyanate component to the total amount of the active hydrogen group in a part of the active hydrogen group-containing component, preferably the active hydrogen group (hydroxyl group) in the polyol component, is, for example, 1.2 or more, preferably 1.3 or more, for example, 3.0 or less, preferably 2.5 or less. In this method, the above components are reacted by a known polymerization method such as bulk polymerization or solution polymerization, preferably solution polymerization, which is easier to adjust the reactivity and viscosity.

[0139] In bulk polymerization, for example, the above components are mixed in a nitrogen atmosphere and reacted at a reaction temperature of 75 to 85° C. for about 1 to 20 hours.

[0140] In the solution polymerization, for example, the above components are mixed in an organic solvent (solvent) under a nitrogen atmosphere and reacted at a reaction temperature of 20 to 80° C. for about 1 to 20 hours.

[0141] Examples of the organic solvent include those which are inactive to isocyanate groups and highly hydrophilic, such as acetone, methyl ethyl ketone, ethyl acetate, tetrahydrofuran, acetonitrile, and N-methylpyrrolidone.

[0142] In the above polymerization, if necessary, a reaction catalyst such as an amine-based, tin-based, or lead-based catalyst may be added, and unreacted polyisocyanate (including NCO compounds directly bonded to a carbon ring) may be removed from the resulting isocyanate-terminated prepolymer by a known method such as distillation or extraction.

[0143] In the above polymerization, for example, when an ionic group is contained, a neutralizing agent is preferably added to neutralize the ionic group to form a salt of the ionic group.

[0144] When the ionic group is an anionic group, examples of the neutralizing agent include conventional bases, such as organic bases (for example, tertiary amines (trialkylamines having 1 to 4 carbon atoms, such as trimethylamine and triethylamine, alkanolamines, such as dimethylethanolamine, methyldiethanolamine, triethanolamine and triisopropanolamine, and heterocyclic amines, such as morpholine)), inorganic bases (ammonia, alkali metal hydroxides (lithium hydroxide, sodium hydroxide, potassium hydroxide, etc.), alkaline earth metal hydroxides (magnesium hydroxide, calcium hydroxide, etc.), and alkali metal carbonates (sodium carbonate, potassium carbonate, etc.)). These bases can be used alone or in combination of two or more.

[0145] The neutralizing agent is added in a ratio of 0.4 equivalents or more, preferably 0.6 equivalents or more, and for example, 1.2 equivalents or less, preferably 1 equivalent or less, per equivalent of the anionic group.

[0146] The isocyanate-terminated prepolymer obtained in this manner is a polyurethane prepolymer having at least one, and preferably two or more, free isocyanate groups at its molecular terminal, and the isocyanate group content (isocyanate group content calculated as solid content excluding solvent) is, for example, 0.3 mass% or more, preferably 0.5 mass% or more, and more preferably 1.0 mass% or more, and for example, 15 mass% or less, preferably 12 mass% or less, and more preferably 10 mass% or less.

[0147] The average functionality of the isocyanate groups is, for example, 1.5 or more, preferably 1.9 or more, more preferably 2.0 or more, and still more preferably 2.1 or more, and for example, 3.0 or less, preferably 2.5 or less.

[0148] When the average functionality of the isocyanate group is within the above range, a stable polyurethane dispersion can be obtained, and adhesion to the substrate, gas barrier properties, and the like can be ensured.

[0149] The number average molecular weight (number average molecular weight measured by GPC using standard polystyrene as a calibration curve) is, for example, 500 or more, preferably 800 or more, and for example, 10,000 or less, preferably 5,000 or less.

[0150] Thereafter, in this method, the isocyanate-terminated prepolymer obtained as described above is reacted with the remainder of the active hydrogen group-containing component, i.e., a chain extender, preferably an amino group-containing component, in, for example, water to obtain a polyurethane dispersion of a polyurethane resin.

[0151] To react the isocyanate-terminated prepolymer with a chain extender in water, for example, the isocyanate-terminated prepolymer is first added to water to disperse the isocyanate-terminated prepolymer in water, and then a chain extender is added thereto to extend the chain of the isocyanate-terminated prepolymer by the chain extender.

[0152] To disperse the isocyanate-terminated prepolymer in water, the isocyanate-terminated prepolymer is added to 100 to 1,000 parts by mass of water with stirring to 100 parts by mass of the isocyanate-terminated prepolymer.

[0153] Thereafter, the chain extender is dropped into the water in which the isocyanate-terminated prepolymer is dispersed under stirring so that the equivalent ratio of the active hydrogen groups (amino groups and hydroxyl groups) of the chain extender to the isocyanate groups of the isocyanate-terminated prepolymer (active hydrogen groups / isocyanate groups) is, for example, 0.6 to 1.2.

[0154] The chain extender is reacted by dropping, and after the dropwise addition is completed, the reaction is completed, for example, at room temperature while continuing to stir. The reaction time until the reaction is completed is, for example, 0.1 hours or more and, for example, 10 hours or less.

[0155] Conversely, water can be added to the isocyanate-terminated prepolymer to disperse the isocyanate-terminated prepolymer in water, and then a chain extender can be added thereto to extend the chains of the isocyanate-terminated prepolymer with the chain extender.

[0156] In this method, the organic solvent and water can be removed as necessary, and further, water can be added to adjust the solid content concentration.

[0157] The solids concentration of the polyurethane dispersion of the obtained polyurethane resin is, for example, 10 mass% or more, preferably 15 mass% or more, more preferably 20 mass% or more, and for example, 60 mass% or less, preferably 50 mass% or less, more preferably 40 mass% or less.

[0158] In addition, the sum of the urethane group concentration and urea group concentration of the polyurethane resin in the polyurethane dispersion is, for example, 25 mass% or more, preferably 30 mass% or more, more preferably 33 mass% or more, and for example, 50 mass% or less, preferably 47 mass% or less, more preferably 45 mass% or less, and even more preferably 40 mass% or less.

[0159] The total of the urethane group concentration and the urea group concentration can be calculated from the charging ratio of the raw material components.

[0160] Moreover, from the viewpoints of gas barrier properties and resistance to high-temperature sterilization treatment (retort treatment), the polyurethane dispersion preferably contains a crosslinking agent (curing agent).

[0161] Examples of the crosslinking agent include crosslinking curing agents such as epoxy curing agents, melamine curing agents, carbodiimide curing agents, aziridine curing agents, oxazoline curing agents, isocyanate curing agents, etc. Among these, more specific examples of the isocyanate curing agent include water-dispersible isocyanate curing agents (for example, blocked isocyanates (for example, tolylene diisocyanate-based blocked isocyanates, hexamethylene diisocyanate-based blocked isocyanates, xylylene diisocyanate-based blocked isocyanates, hydrogenated xylylene diisocyanate-based blocked isocyanates, etc.), unblocked polyisocyanates containing hydrophilic groups, etc.).

[0162] When a crosslinking agent is blended, the blending ratio of the crosslinking agent, in terms of solid content, per 100 parts by mass of the polyurethane resin is, for example, 0.1 parts by mass or more, preferably 1 part by mass or more, and for example, 50 parts by mass or less, preferably 30 parts by mass or less.

[0163] Furthermore, various additives can be blended into the polyurethane dispersion as necessary. Examples of the additives include silane coupling agents, alkoxysilane compounds, stabilizers (antioxidants, heat stabilizers, ultraviolet absorbers, etc.), plasticizers, antistatic agents, lubricants, antiblocking agents, surfactants, dispersion stabilizers, colorants (pigments, dyes, etc.), fillers, colloidal silica, inorganic particles, inorganic oxide particles, and crystal nucleating agents.

[0164] The additives may be blended in advance with each of the raw material components described above, or may be blended with the isocyanate-terminated prepolymer or polyurethane resin after synthesis, or may be blended simultaneously with the blending of these components.

[0165] The mixing ratio of the additives is not particularly limited and may be appropriately set depending on the purpose and application.

[0166] If necessary, a thermoplastic resin having gas barrier properties may be blended within a range in which the gas barrier properties are not impaired.

[0167] Examples of thermoplastic resins having gas barrier properties include polyvinyl alcohol, ethylene-vinyl alcohol copolymers, polyvinylidene chloride or vinylidene chloride copolymers, starch, polysaccharides such as cellulose, and the like.

[0168] In such a polyurethane dispersion, the active hydrogen group-containing component contains a diol having 2 to 4 carbon atoms, and an active hydrogen group-containing compound that contains a hydrophilic group.

[0169] A polyurethane dispersion obtained by using such an active hydrogen group-containing component can provide a polyurethane layer having excellent gas barrier properties.

[0170] Furthermore, in the polyurethane dispersion of the present invention, the polyisocyanate component contains a polyisocyanate compound having a carbon ring and an isocyanate group directly bonded to the carbon ring in a proportion of 90 mass % or more based on the total amount of the polyisocyanate component.

[0171] In such polyurethane dispersions, since an isocyanate group is directly bonded to a carbon ring in the polyisocyanate component, the degree of freedom of the isocyanate group and the degree of freedom of the urethane bond in the polyurethane resin are limited.

[0172] As a result, deformation and deterioration of the polyurethane layer due to high-temperature sterilization treatment (retort treatment) can be suppressed, and even if the polyurethane layer is laminated on the inorganic layer, damage to the inorganic layer can be suppressed.

[0173] Furthermore, in the laminate of the present invention, since the dried product of the above-mentioned polyurethane dispersion is laminated onto the inorganic layer, deformation and deterioration of the polyurethane layer due to high-temperature sterilization treatment (retort treatment) can be suppressed, and the laminate maintains excellent gas barrier properties even after high-temperature sterilization treatment (retort treatment).

[0174] Therefore, the above polyurethane dispersion can be suitably used in the production of a laminate having a polyurethane layer as a gas barrier layer.

[0175] In FIG. 1, the laminate 1 includes a substrate 2 and a polyurethane layer 3 laminated on the substrate 2.

[0176] The substrate 2 includes an inorganic layer 4 as an essential layer.

[0177] More specifically, the base material 2 includes only the inorganic layer 4, or includes the inorganic layer 4 and a resin layer 5 supporting the inorganic layer 4 from the lower surface.

[0178] Preferably, the substrate 2 includes an inorganic layer 4 and a resin layer 5 supporting the inorganic layer 4 .

[0179] In other words, the substrate 2 includes the resin layer 5 and the inorganic layer 4 laminated on the resin layer 5 .

[0180] The resin layer 5 is formed, for example, from a plastic (for example, a thermoplastic resin, a thermosetting resin, etc.), and is preferably formed from a thermoplastic resin.

[0181] Examples of thermoplastic resins include polyolefin resins (e.g., polyethylene, polypropylene, propylene-ethylene copolymers, etc.), polyester resins (e.g., polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, etc.), polyamide resins (e.g., Nylon 6 (registered trademark), Nylon 66 (registered trademark), polymetaxylylene adipamide, etc.), vinyl resins (e.g., polyvinyl alcohol, ethylene-vinyl alcohol copolymers, polystyrene, polyvinyl acetate, etc.), acrylic resins (e.g., polymethyl methacrylate, polyacrylonitrile, etc.), polycarbonate resins (e.g., bisphenol A polycarbonate, etc.), and cellulose resins (e.g., cellophane, cellulose acetate, etc.). Preferred are polyolefin resins, polyester resins, and polyamide resins. More preferred are polypropylene, polyethylene terephthalate, and Nylon 6 (registered trademark).

[0182] The resin layer 5 is made of a single layer or a laminate of the same or two or more types of materials.

[0183] The shape of the resin layer 5 is not particularly limited, and examples thereof include a film shape, a sheet shape, a bottle shape, a cup shape, etc. A film shape is preferable.

[0184] The resin layer 5 may be a non-stretched substrate, or a uniaxially or biaxially stretched substrate, and the resin layer 5 may be subjected to a surface treatment (corona discharge treatment, etc.), an anchor coat treatment, or an undercoat treatment.

[0185] As the resin layer 5, preferably, a film formed from a thermoplastic resin is used, and more preferably, a polyethylene terephthalate film is used.

[0186] The thickness of the resin layer 5 is not particularly limited, but is, for example, 5 μm or more, preferably 10 μm or more, and for example, 200 μm or less, preferably 100 μm or less.

[0187] The inorganic layer 4 is a layer made of an inorganic material, and more specifically, a thin film made of an inorganic material.

[0188] Examples of inorganic materials include inorganic substances containing metals such as magnesium, calcium, and barium in Group 2 of the Periodic Table (based on the IUPAC Periodic Table of the Elements (version date 22 June 007); the same applies below), titanium and zirconium in Group 4, aluminum and indium in Group 13, and silicon, germanium, and tin in Group 14, such as inorganic oxides containing metal oxides such as magnesium oxide, titanium oxide, aluminum oxide, indium oxide, silicon oxide, and tin oxide, and inorganic nitride oxides such as silicon oxynitride.

[0189] From the viewpoint of gas barrier properties and production efficiency, aluminum, silicon and oxides thereof are preferable. Furthermore, a plurality of these metals and their oxides may be combined to form a layer made of a metal and / or a metal oxide.

[0190] From the viewpoints of gas barrier properties and production efficiency, it is more preferable that the inorganic layer 4 contains aluminum oxide and / or silicon oxide.

[0191] The inorganic layer 4 is formed on one surface of the resin layer 5 by, for example, a deposition method (vacuum deposition method, EB deposition method, etc.), a sputtering method, an ion plating method, a lamination method, a plasma vapor phase growth method (CVD method), or the like.

[0192] From the viewpoint of productivity, preferably, a vapor deposition method is used, and more preferably, a vacuum deposition method is used In other words, the inorganic layer 4 is preferably an inorganic vapor deposition layer.

[0193] For example, in the vacuum deposition method, the heating method of the vacuum deposition apparatus is preferably an electron beam heating method, a resistance heating method, or an induction heating method.

[0194] The thickness of the inorganic layer 4 is appropriately selected depending on the type and configuration of the inorganic material, and is, for example, 1 nm or more, preferably 2 nm or more, and for example, 500 nm or less, preferably 300 nm or less.

[0195] The thickness of the substrate 2 (the total thickness of the resin layer 5 and the inorganic layer 4) is, for example, 5 μm or more, preferably 10 μm or more, and for example, 200 μm or less, preferably 100 μm or less.

[0196] The polyurethane layer 3 is formed from the above-mentioned polyurethane resin (the aqueous polyurethane resin contained in the polyurethane dispersion), and more specifically, the polyurethane layer 3 is a dried product of the above-mentioned polyurethane dispersion.

[0197] From the viewpoint of manufacturing efficiency, such a polyurethane layer 3 is preferably formed by applying and drying a polyurethane dispersion containing the above-mentioned polyurethane resin to the surface of the inorganic layer 4 (the surface opposite to the contact surface of the inorganic layer 4 with the resin layer 5).

[0198] More specifically, to form the polyurethane layer 3, a coating agent (coating liquid) is prepared by adjusting the concentration of the polyurethane dispersion obtained by the above method, and the obtained coating agent is applied onto the inorganic layer 4 and dried.

[0199] The concentration of the polyurethane dispersion can be adjusted by a known method, for example, by adding or removing water or a known organic solvent.

[0200] Furthermore, for example, a mono-ol can be added to the coating agent in order to impart wettability to the inorganic layer 4 or to dilute the coating agent.

[0201] Examples of monools include methanol, ethanol, propanol, isopropanol, butanol, 2-ethylhexyl alcohol, other alkanols (C5 to C38) and aliphatic unsaturated alcohols (C9 to C24), alkenyl alcohols, 2-propen-1-ol, alkadienols (C6 to C8), and 3,7-dimethyl-1,6-octadien-3-ol.

[0202] These monools can be used alone or in combination of two or more kinds.

[0203] As the monool, preferably, 2-propanol is used.

[0204] The mixing ratio of the monol is, for example, 1 part by mass or more, preferably 2 parts by mass or more, and for example, 50 parts by mass or less, preferably 35 parts by mass or less, in 100 parts by mass of the coating agent, the concentration of which is adjusted as necessary.

[0205] The solids concentration of the coating agent is, for example, 0.5 mass % or more, preferably 1 mass % or more, and for example, 30 mass % or less, preferably 25 mass % or less.

[0206] The method for applying the coating agent is not particularly limited, and examples thereof include known coating methods such as gravure coating, reverse coating, roll coating, bar coating, spray coating, air knife coating, and dipping.

[0207] Alternatively, the coating may be carried out in-line when the substrate 2 is produced.

[0208] Specifically, when the substrate 2 is in the form of a film, after uniaxial stretching in the longitudinal direction during film formation, a coating agent can be applied and dried by a gravure coating method or the like, and then a biaxial stretching process can be performed to provide the polyurethane layer 3 on the inorganic layer 4.

[0209] Furthermore, when the substrate 2 is bottle-shaped, a coating agent can be applied to the preform before blow molding by a dipping method or the like, dried, and then blow molded to provide the polyurethane layer 3 on the inorganic layer 4.

[0210] The drying conditions are such that the drying temperature is, for example, 40° C. or more, preferably 50° C. or more, more preferably 90° C. or more, and for example, 200° C. or less, preferably 180° C. or less, more preferably 150° C. or less, and the drying time is, for example, 0.1 minutes or more, preferably 0.2 minutes or more, and for example, 10 minutes or less, preferably 5 minutes or less.

[0211] As a result, a polyurethane layer 3 made of a polyurethane resin (dried product of a polyurethane dispersion) can be formed on the inorganic layer 4.

[0212] The thickness of the polyurethane layer 3 is, for example, 0.05 g / m2 as the laminated amount of polyurethane resin (after drying). 2 More than 0.1 g / m 2 More preferably, 0.2 g / m 2 or more, for example, 10 g / m 2 Preferably, 7 g / m or less 2 Less than 5 g / m 2 More preferably, 3 g / m or less 2 More preferably, 2 g / m 2 Below, particularly preferably 1 g / m 2 The following is the result.

[0213] Then, as described above, by forming the polyurethane layer 3 on the inorganic layer 4 of the substrate 2, the laminate 1 including the substrate 2 (inorganic layer 4) and the polyurethane layer 3 can be obtained.

[0214] The laminate 1 has a thickness of, for example, 5 μm or more, preferably 10 μm or more, and for example, 1 mm or less, preferably 0.5 mm or less.

[0215] If necessary, the obtained laminate 1 may be aged, for example, at 30 to 60° C. for about 2 to 5 days.

[0216] The laminate 1 includes the above-mentioned polyurethane layer 3 , and also includes an inorganic layer 4 disposed so as to be in contact with one surface of the polyurethane layer 3 .

[0217] That is, in such a laminate 1, the dried product of the above-mentioned polyurethane dispersion is laminated onto the inorganic layer 4, so that deformation and deterioration of the polyurethane layer 3 due to high-temperature sterilization treatment (retort treatment) can be suppressed, and the gas barrier properties are excellent even after the high-temperature sterilization treatment (retort treatment).

[0218] In addition, in the laminate 1, a layered inorganic compound can be dispersed in the polyurethane layer 3 in order to improve the gas barrier property.

[0219] Specifically, for example, a mixture of the above-mentioned polyurethane dispersion and a layered inorganic compound can be applied to the inorganic layer 4 of the substrate 2 and dried to form a polyurethane layer 3 in which the layered inorganic compound is dispersed.

[0220] Examples of the layered inorganic compound include a swellable layered inorganic compound, a non-swellable layered inorganic compound, etc. From the viewpoint of gas barrier properties, a swellable layered inorganic compound is preferable.

[0221] The swelling layered inorganic compound is a clay mineral that consists of extremely thin unit crystals and has the property of coordinating or absorbing a solvent between the unit crystal layers and swelling.

[0222] Specific examples of the swellable layered inorganic compound include hydrated silicates (such as phyllosilicate minerals), kaolinite group clay minerals (such as halloysite, kaolinite, endelite, dickite, and nacrite), antigorite group clay minerals (such as antigorite and chrysotile), smectite group clay minerals (such as montmorillonite, beidellite, nontronite, saponite, hectorite, sauconite, and stevensite), vermiculite group clay minerals (such as vermiculite), mica or mica group clay minerals (such as muscovite and phlogopite, margarite, tetrasilylic mica, and taeniolite), and synthetic mica.

[0223] These swelling layered inorganic compounds may be natural clay minerals or synthetic clay minerals, and may be used alone or in combination of two or more kinds. Preferred examples include smectite clay minerals (such as montmorillonite), mica clay minerals (such as water-swelling mica), and synthetic mica, and more preferred examples include synthetic mica.

[0224] The average particle size of the layered inorganic compound is, for example, 50 nm or more, preferably 100 nm or more, and usually 100 μm or less, for example, 75 μm or less, preferably 50 μm or less. The aspect ratio of the layered inorganic compound is, for example, 10 or more, preferably 20 or more, more preferably 100 or more, and for example, 5000 or less, preferably 4000 or less, more preferably 3000 or less.

[0225] To form the polyurethane layer 3 in which the layered inorganic compound is dispersed, for example, the polyurethane dispersion and the layered inorganic compound are mixed together to prepare a hybrid coating agent, which is then applied onto the inorganic layer 4 of the substrate 2 and dried.

[0226] To prepare the mixture (hybrid coating agent), first, the layered inorganic compound is dispersed in water, and then, a polyurethane dispersion (containing a polyurethane resin) is added to the dispersion.

[0227] The blending ratio of the polyurethane resin and the layered inorganic compound is 0.1 parts by mass or more, preferably 1 part by mass or more, and for example, 50 parts by mass or less, preferably 30 parts by mass or less, of the layered inorganic compound per 100 parts by mass of the total mass of the polyurethane resin and the layered inorganic compound.

[0228] When the blending ratio of the polyurethane resin to the layered inorganic compound is within the above range, the gas barrier properties are maintained, and the adhesion to the substrate, transparency, and cost reduction can be improved.

[0229] The total concentration of the polyurethane resin and the layered inorganic compound in the obtained mixture (hybrid coating agent) is, for example, 0.1 mass% or more, preferably 0.5 mass% or more, and for example, 15 mass% or less, preferably 12 mass% or less.

[0230] In the mixture (hybrid coating agent), since the layered inorganic compound may undergo secondary aggregation, it is preferable to disperse or mix the layered inorganic compound in a solvent and then disperse the compound using a mechanical forced dispersion process in which a shear force acts, such as a dispersion process using a homomixer, colloid mill, jet mill, kneader, bead mill, sand mill, ball mill, three-roll mill, ultrasonic dispersion device, or the like.

[0231] The method for applying the hybrid coating agent is not particularly limited, and may be any of the known coating methods described above.

[0232] The drying conditions are such that the drying temperature is, for example, 40° C. or more, preferably 50° C. or more, and for example, 200° C. or less, preferably 180° C. or less, and the drying time is, for example, 0.1 minute or more, preferably 0.2 minute or more, and for example, 10 minutes or less, preferably 5 minutes or less.

[0233] As a result, a polyurethane layer 3 made of a polyurethane resin (dried product of a polyurethane dispersion) and a layered inorganic compound can be formed on the inorganic layer 4 of the substrate 2.

[0234] The thickness of the polyurethane layer 3 is, for example, 0.1 g / m2 as the lamination amount of the polyurethane resin and the layered inorganic compound (after drying). 2 More than 0.2 g / m 2 More preferably, 0.6 g / m 2 or more, for example, 10 g / m 2 Preferably, 7 g / m or less 2 Less than 5 g / m 2 The following is the result.

[0235] Then, as described above, the polyurethane layer 3 is formed on the inorganic layer 4 of the substrate 2, whereby the laminate 1 can be obtained.

[0236] The laminate 1 has a thickness of, for example, 5 μm or more, preferably 10 μm or more, and for example, 1 mm or less, preferably 0.5 mm or less.

[0237] In addition, in the laminate 1, the mass proportion of the layered inorganic compound relative to 100 parts by mass of the total amount of the polyurethane layer 3 is, for example, 0.1 parts by mass or more, preferably 0.2 parts by mass or more, and more preferably 1 part by mass or more, and for example, 90 parts by mass or less, preferably 70 parts by mass or less, and more preferably 50 parts by mass or less.

[0238] When the mass proportion of the layered inorganic compound is within the above range, adhesion to the substrate and transparency can be improved, and the blending proportion of the layered inorganic compound can be reduced, thereby improving cost.

[0239] If necessary, the obtained laminate 1 may be aged, for example, at 30 to 60° C. for about 2 to 5 days.

[0240] Such a laminate 1 includes a polyurethane layer 3 obtained by using the above-mentioned polyurethane dispersion, and further includes a layered inorganic compound dispersed in the polyurethane layer 3, and therefore has particularly excellent gas barrier properties.

[0241] The laminate 1 thus obtained not only has excellent gas barrier properties, but also has excellent adhesion to the inorganic layer 4, and furthermore, can maintain the gas barrier properties and adhesion even after high-temperature sterilization treatment.

[0242] Therefore, the laminate 1 is suitable for use in the field of gas barrier films, specifically, in packaging films for food and medicine, food packaging containers (including bottles), optical films, industrial films, etc., and is particularly suitable for use as a food packaging film for contents that require high-temperature sterilization treatment such as boiling sterilization and retort sterilization, or heat treatment such as cooking.

[0243] In addition, the above-mentioned coating agent or hybrid coating agent can be mixed with a colorant such as a pigment to prepare a printing ink, which can be applied to plastic films, paper, various containers, etc., and can also be suitably used as a printed film or printed body.

[0244] In the above explanation, the inorganic layer 4 is arranged in contact with only one surface of the polyurethane layer 3, but in the laminate 1, it is sufficient that the inorganic layer 4 is arranged in contact with at least one surface of the polyurethane layer 3, and for example, the inorganic layer 4 may be arranged in contact with both surfaces of the polyurethane layer 3.

[0245] Furthermore, in this laminate 1, another polyurethane layer 6 can be laminated on the surface of the polyurethane layer 3 as shown in FIG.

[0246] Hereinafter, the polyurethane layer 3 disposed in contact with the inorganic layer 4 will be referred to as a first polyurethane layer 3. The polyurethane dispersion and the polyurethane resin used in forming the first polyurethane layer 3 will be referred to as a first polyurethane dispersion and a first polyurethane resin, respectively.

[0247] In the following, the polyurethane layer 6 laminated on the first polyurethane layer 3 is referred to as a second polyurethane layer 6. In addition, the following polyurethane dispersion and the following polyurethane resin used in forming the second polyurethane layer 6 are referred to as a second polyurethane dispersion and a second polyurethane resin, respectively.

[0248] 2, the laminate 1 includes a first polyurethane layer 3 containing a first polyurethane resin, and a substrate 2 arranged such that an inorganic layer 4 is in contact with one surface of the first polyurethane layer 3. Furthermore, the laminate 1 has a second polyurethane layer 6 laminated on the other surface of the first polyurethane layer 3 opposite the surface in contact with the inorganic layer 4.

[0249] The second polyurethane layer 6 is a dried product of a second polyurethane dispersion containing a second polyurethane resin.

[0250] The second polyurethane resin is a reaction product obtained by at least reacting a second polyisocyanate component with a second active hydrogen group-containing component.

[0251] The second polyisocyanate component contains the second polyisocyanate compound as a main component (for example, at a ratio of 90% by mass or more, preferably 95% by mass or more, based on the total amount of the second polyisocyanate component).

[0252] Preferably, the second polyisocyanate component consists of a second polyisocyanate compound.

[0253] The second polyisocyanate compound contains, for example, xylylene diisocyanate and / or hydrogenated xylylene diisocyanate.

[0254] Xylylene diisocyanate (XDI) includes, as structural isomers, 1,2-xylylene diisocyanate (o-XDI), 1,3-xylylene diisocyanate (m-XDI), and 1,4-xylylene diisocyanate (p-XDI).

[0255] These xylylene diisocyanates can be used alone or in combination of two or more kinds. As the xylylene diisocyanate, preferred are 1,3-xylylene diisocyanate and 1,4-xylylene diisocyanate, and more preferred are 1,3-xylylene diisocyanate.

[0256] In addition, examples of hydrogenated xylylene diisocyanate (also known as bis(isocyanatomethyl)cyclohexane) (H6XDI) include 1,2-hydrogenated xylylene diisocyanate (1,2-bis(isocyanatomethyl)cyclohexane, o-H6XDI), 1,3-hydrogenated xylylene diisocyanate (1,3-bis(isocyanatomethyl)cyclohexane, m-H6XDI), and 1,4-hydrogenated xylylene diisocyanate (1,4-bis(isocyanatomethyl)cyclohexane, p-H6XDI) as structural isomers.

[0257] These hydrogenated xylylene diisocyanates can be used alone or in combination of two or more. Preferred hydrogenated xylylene diisocyanates include 1,3-hydrogenated xylylene diisocyanate and 1,4-hydrogenated xylylene diisocyanate, and more preferably 1,3-hydrogenated xylylene diisocyanate.

[0258] Furthermore, the xylylene diisocyanate and / or hydrogenated xylylene diisocyanate includes the same derivatives as those mentioned above.

[0259] Examples of the derivatives include multimers of xylylene diisocyanate and / or hydrogenated xylylene diisocyanate, allophanate modified products, polyol modified products, biuret modified products, urea modified products, oxadiazinetrione modified products, carbodiimide modified products, uretdione modified products, and uretonimine modified products.

[0260] The derivatives can be used alone or in combination of two or more kinds.

[0261] As the second polyisocyanate compound, preferably, xylylene diisocyanate is used.

[0262] Furthermore, the second polyisocyanate component can contain other polyisocyanates as necessary.

[0263] Examples of other polyisocyanates include polyisocyanates such as aromatic polyisocyanates, araliphatic polyisocyanates (excluding xylylene diisocyanate), aliphatic polyisocyanates, and alicyclic polyisocyanates (excluding hydrogenated xylylene diisocyanate).

[0264] Examples of aromatic polyisocyanates include aromatic diisocyanates such as tolylene diisocyanate (2,4- or 2,6-tolylene diisocyanate or a mixture thereof) (TDI), phenylene diisocyanate (m-, p-phenylene diisocyanate or a mixture thereof), 4,4'-diphenyl diisocyanate, 1,5-naphthalene diisocyanate (NDI), diphenylmethane diisocyanate (4,4'-, 2,4'-, or 2,2'-diphenylmethane diisocyanate or a mixture thereof) (MDI), 4,4'-toluidine diisocyanate (TODI), and 4,4'-diphenyl ether diisocyanate.

[0265] Examples of the aromatic aliphatic polyisocyanates (excluding xylylene diisocyanate) include aromatic aliphatic diisocyanates such as tetramethyl xylylene diisocyanate (1,3- or 1,4-tetramethyl xylylene diisocyanate or a mixture thereof) (TMXDI) and ω,ω'-diisocyanate-1,4-diethylbenzene.

[0266] Examples of the aliphatic polyisocyanate include aliphatic diisocyanates such as trimethylene diisocyanate, 1,2-propylene diisocyanate, butylene diisocyanate (tetramethylene diisocyanate, 1,2-butylene diisocyanate, 2,3-butylene diisocyanate, 1,3-butylene diisocyanate), 1,5-pentamethylene diisocyanate (PDI), 1,6-hexamethylene diisocyanate (also known as hexamethylene diisocyanate) (HDI), 2,4,4- or 2,2,4-trimethylhexamethylene diisocyanate, and 2,6-diisocyanate methylcaprate.

[0267] Examples of alicyclic polyisocyanates (excluding hydrogenated xylylene diisocyanate) include 1,3-cyclopentane diisocyanate, 1,3-cyclopentene diisocyanate, cyclohexane diisocyanate (1,4-cyclohexane diisocyanate, 1,3-cyclohexane diisocyanate), 3-isocyanatomethyl-3,5,5-trimethylcyclohexyl isocyanate (also known as isophorone diisocyanate) (IPDI), methylene bis(cyclohexyl isocyanate) (also known as bis(isocyanatocyclohexyl)methane) (4,4'-, 2,4'-, or 2,2'-methylene bis(cyclohexyl isocyanate) their trans,trans-isomer, trans,cis-isomer, cis,cis-isomer, or mixtures thereof) (H 12Examples of the diisocyanate include alicyclic diisocyanates such as methylcyclohexane diisocyanate (methyl-2,4-cyclohexane diisocyanate, methyl-2,6-cyclohexane diisocyanate), and norbornane diisocyanate (various isomers or a mixture thereof) (NBDI). Preferably, 4,4'-methylenebis(cyclohexyl isocyanate) is used.

[0268] Other polyisocyanates include derivatives of the same types listed above.

[0269] These other polyisocyanates can be used alone or in combination of two or more kinds. Preferred are aromatic aliphatic polyisocyanates and alicyclic polyisocyanates, more preferably alicyclic polyisocyanates, and even more preferably bis(isocyanatocyclohexyl)methane.

[0270] When other polyisocyanates (polyisocyanates other than xylylene diisocyanate and hydrogenated xylylene diisocyanate) are blended, the content of xylylene diisocyanate and hydrogenated xylylene diisocyanate (the total amount of them when used in combination) relative to the total amount of the second polyisocyanate component is, for example, 50 mass% or more, preferably 60 mass% or more, more preferably 80 mass% or more, and for example, 99 mass% or less.

[0271] As the second polyisocyanate component, a combination of xylylene diisocyanate and bis(isocyanatocyclohexyl)methane is more preferable.

[0272] By using xylylene diisocyanate and bis(isocyanatocyclohexyl)methane in combination, it is possible to obtain a polyurethane dispersion with excellent water dispersibility and a small average particle size without impairing the gas barrier properties.

[0273] When xylylene diisocyanate and bis(isocyanatocyclohexyl)methane are used in combination, the amount of xylylene diisocyanate is, for example, 60 parts by mass or more, preferably 70 parts by mass or more, more preferably 80 parts by mass or more, and, for example, 95 parts by mass or less, preferably 93 parts by mass or less, more preferably 90 parts by mass or less, relative to 100 parts by mass of the total amount of xylylene diisocyanate and bis(isocyanatocyclohexyl)methane (preferably the second polyisocyanate component). Also, the amount of bis(isocyanatocyclohexyl)methane is, for example, 5 parts by mass or more, preferably 7 parts by mass or more, more preferably 10 parts by mass or more, and, for example, 40 parts by mass or less, preferably 30 parts by mass or less, more preferably 20 parts by mass or less.

[0274] The second active hydrogen group-containing component preferably includes the same polyol component as above, and the same amino group-containing compound as above.

[0275] That is, the second active hydrogen group-containing component preferably contains a second polyol component similar to the above polyol component, more specifically, contains a diol having 2 to 4 carbon atoms and the above active hydrogen group-containing compound having a hydrophilic group.

[0276] The diol having 2 to 4 carbon atoms is preferably an alkanediol having 2 to 4 carbon atoms, and more preferably ethylene glycol.

[0277] The mixing ratio of the diol having 2 to 4 carbon atoms, relative to 100 parts by mass of the total amount of the second polyol component, is, for example, 20 parts by mass or more, preferably 30 parts by mass or more, more preferably 50 parts by mass or more, and for example, 80 parts by mass or less, preferably 70 parts by mass or less.

[0278] As the active hydrogen group-containing compound containing a hydrophilic group, preferably, an active hydrogen group-containing compound containing an ionic group is used, more preferably, a carboxy group-containing polyol is used, and further preferably, a polyhydroxyalkanoic acid is used.

[0279] The mixing ratio of the active hydrogen group-containing compound that contains a hydrophilic group, relative to 100 parts by mass of the total amount of the second polyol component, is, for example, 20 parts by mass or more, preferably 25 parts by mass or more, and more preferably 30 parts by mass or more, and for example, 50 parts by mass or less, preferably 45 parts by mass or less, and more preferably 40 parts by mass or less.

[0280] The second polyol component may further contain other low molecular weight polyols (such as the above-mentioned diols (dihydric alcohols) having 5 or more carbon atoms, the above-mentioned low molecular weight polyols having three or more hydric atoms, etc.) or the above-mentioned high molecular weight polyols.

[0281] Preferably, the second polyol component contains other low molecular weight polyols.

[0282] As the other low molecular weight polyol, preferably, a low molecular weight polyol having a valence of three or more is used.

[0283] When other low molecular weight polyols are blended, the blending ratio is, for example, 30 parts by mass or less, preferably 20 parts by mass or less, more preferably 10 parts by mass or less, per 100 parts by mass of the total amount of the second polyol component, and for example, 1 part by mass or more.

[0284] Furthermore, when a trihydric or higher low-molecular-weight polyol is used as the other low-molecular-weight polyol, the combined ratio of the diol having 2 to 4 carbon atoms and the trihydric or higher low-molecular-weight polyol is, for example, 1 part by mass or more, preferably 5 parts by mass or more, and for example, 20 parts by mass or less, preferably 10 parts by mass or less, per 100 parts by mass of the total amount of the diol having 2 to 4 carbon atoms and the trihydric alcohol.

[0285] From the viewpoint of gas barrier properties, the second active hydrogen group-containing component (second polyol component) preferably does not contain a high molecular weight polyol.

[0286] More preferably, the second polyol component comprises the above-mentioned diol having 2 to 4 carbon atoms, an active hydrogen group-containing compound containing a hydrophilic group, and a trivalent or higher low-molecular-weight polyol.

[0287] Furthermore, when the second polyurethane layer 6 is laminated on the surface of the first polyurethane layer 3 as in this laminate 1 (see FIG. 2), it is particularly preferable that the polyol component (second polyol component) used as a raw material for producing the second polyurethane layer 6 contains a low-molecular-weight polyol having a valence of three or more. On the other hand, the polyol component (first polyol component) used as a raw material for producing the first polyurethane layer 3 does not preferably contain a low-molecular-weight polyol having a valence of three or more.

[0288] In this way, if the polyol component used as a raw material for producing the second polyurethane layer 6 contains a low-molecular-weight polyol having a valence of three or more, and the polyol component used as a raw material for producing the first polyurethane layer 3 does not contain a low-molecular-weight polyol having a valence of three or more, heat resistance can be improved.

[0289] Furthermore, the second active hydrogen group-containing component can further contain the amino group-containing component described above as the second amino group-containing component, in addition to the second polyol component.

[0290] The second amino group-containing component is preferably an amino alcohol or an amino group-containing alkoxysilyl compound, and more preferably 2-((2-aminoethyl)amino)ethanol (also known as N-(2-aminoethyl)ethanolamine) or N-β(aminoethyl)γ-aminopropyltrimethoxysilane (also known as N-2-(aminoethyl)-3-aminopropyltrimethoxysilane).

[0291] As the second amino group-containing component, more preferably, amino alcohol is used alone, and amino alcohol and amino group-containing alkoxysilyl compound are used in combination, and particularly preferably, amino alcohol and amino group-containing alkoxysilyl compound are used in combination.When these are used in combination, from the viewpoint of gas barrier properties, the amino alcohol is, for example, 50 parts by mass or more, preferably 60 parts by mass or more, more preferably 66 parts by mass or more, and for example, 95 parts by mass or less, preferably 90 parts by mass or less, more preferably 85 parts by mass or less, relative to the total amount of 100 parts by mass of amino alcohol and amino group-containing alkoxysilyl compound.In addition, the amino group-containing alkoxysilyl compound is, for example, 5 parts by mass or more, preferably 10 parts by mass or more, more preferably 15 parts by mass or more, and for example, 50 parts by mass or less, preferably 40 parts by mass or less, more preferably 30 parts by mass or less.

[0292] The secondary amino group-containing component is preferably used as a chain extender in the prepolymer method.

[0293] When the second active hydrogen group-containing component has both the second polyol component and the second amino group-containing component, the content ratio of the second polyol component is, for example, 50 parts by mass or more, preferably 60 parts by mass or more, and, for example, 80 parts by mass or less, preferably 70 parts by mass or less, relative to 100 parts by mass of the total amount of the active hydrogen group-containing components. The content ratio of the second amino group-containing component is, for example, 5 parts by mass or more, preferably 10 parts by mass or more, and, for example, 40 parts by mass or less, preferably 30 parts by mass or less.

[0294] In the reaction between the second polyisocyanate component and the second active hydrogen group-containing component, a known method such as the one-shot method or the prepolymer method is used.

[0295] Preferably, the second polyurethane dispersion containing the second polyurethane resin is obtained by a method similar to the prepolymer method described above.

[0296] More specifically, in the one-shot method, for example, the above-mentioned components are formulated (mixed) so that the equivalent ratio (NCO / active hydrogen group) of the isocyanate group in the second polyisocyanate component to the active hydrogen group (hydroxyl group, amino group) in the second active hydrogen group-containing component is, for example, 0.8 or more, preferably 0.9 or more, for example, 1.2 or less, preferably 1.1 or less, and a curing reaction is carried out by a known polymerization method such as the above-mentioned bulk polymerization or the above-mentioned solution polymerization, for example, at room temperature to 250°C, preferably room temperature to 200°C, for example, for 5 minutes to 72 hours, preferably 4 to 24 hours.

[0297] In the prepolymer method, first, the second polyisocyanate component is reacted with at least a part of the second active hydrogen group-containing component (the active hydrogen group-containing component other than the chain extender (second polyol component)) to synthesize an isocyanate group-terminated prepolymer.

[0298] In this reaction, the equivalent ratio (isocyanate group / active hydrogen group) of the isocyanate group in the second polyisocyanate component to the total amount of the active hydrogen group in the part of the second active hydrogen group-containing component, preferably the active hydrogen group (hydroxyl group) in the second polyol component, is, for example, 1.2 or more, preferably 1.3 or more, for example, 3.0 or less, preferably 2.5 or less. In this method, the above components are reacted by a known polymerization method such as the above bulk polymerization or the above solution polymerization, preferably solution polymerization, which is easier to adjust the reactivity and viscosity.

[0299] In the above polymerization, a reaction catalyst such as an amine-based, tin-based, or lead-based catalyst may be added as necessary, and unreacted polyisocyanate can be removed from the resulting isocyanate-terminated prepolymer by a known method such as distillation or extraction.

[0300] In the above polymerization, for example, when an ionic group is contained, it is preferable to neutralize the ionic group by adding the above-mentioned neutralizing agent to form a salt of the ionic group.

[0301] Thereafter, in this method, the isocyanate-terminated prepolymer obtained as described above is reacted with the remainder of the second active hydrogen group-containing component, i.e., a chain extender, preferably an amino group-containing component, in, for example, water to obtain a second polyurethane dispersion of a second polyurethane resin.

[0302] To react the isocyanate-terminated prepolymer with a chain extender in water, the chain extender is added dropwise to the water in which the isocyanate-terminated prepolymer is dispersed under stirring in the same manner as described above, so that the equivalent ratio of the active hydrogen groups (amino groups and hydroxyl groups) of the chain extender to the isocyanate groups of the isocyanate-terminated prepolymer (active hydrogen groups / isocyanate groups) is, for example, 0.6 to 1.2.

[0303] It is also possible to add water to the isocyanate-terminated prepolymer to disperse the isocyanate-terminated prepolymer in water, and then add a chain extender thereto to extend the chains of the isocyanate-terminated prepolymer with the chain extender.

[0304] In this method, the organic solvent and water can be removed as necessary, and further, water can be added to adjust the solid content concentration.

[0305] The solids concentration of the second polyurethane dispersion of the obtained second polyurethane resin is, for example, 10 mass% or more, preferably 15 mass% or more, more preferably 20 mass% or more, and for example, 60 mass% or less, preferably 50 mass% or less, more preferably 45 mass% or less.

[0306] In addition, the sum of the urethane group concentration and urea group concentration of the second polyurethane resin in the second polyurethane dispersion is, for example, 25 mass% or more, preferably 30 mass% or more, more preferably 33 mass% or more, and for example, 50 mass% or less, preferably 47 mass% or less, more preferably 45 mass% or less.

[0307] In addition, the second polyurethane dispersion may contain the above-mentioned crosslinking agent (curing agent) if necessary.

[0308] When a crosslinking agent is blended, the blending ratio of the crosslinking agent, in terms of solid content, per 100 parts by mass of the second polyurethane resin is, for example, 0.1 parts by mass or more, preferably 1 part by mass or more, and for example, 50 parts by mass or less, preferably 30 parts by mass or less.

[0309] Furthermore, the second polyurethane dispersion may contain various additives as necessary. Examples of the additives include silane coupling agents, alkoxysilane compounds, stabilizers (antioxidants, heat stabilizers, ultraviolet absorbers, etc.), plasticizers, antistatic agents, lubricants, antiblocking agents, surfactants, dispersion stabilizers, colorants (pigments, dyes, etc.), fillers, colloidal silica, inorganic particles, inorganic oxide particles, and crystal nucleating agents.

[0310] The additives may be blended in advance with each of the raw material components described above, or may be blended with the isocyanate-terminated prepolymer or the second polyurethane resin after synthesis, or may be blended simultaneously with the blending of these components.

[0311] The mixing ratio of the additives is not particularly limited and may be appropriately set depending on the purpose and application.

[0312] Furthermore, the second polyurethane dispersion may contain a thermoplastic resin having gas barrier properties, if necessary, within the range in which the gas barrier properties are not impaired.

[0313] Examples of thermoplastic resins having gas barrier properties include polyvinyl alcohol, ethylene-vinyl alcohol copolymers, polyvinylidene chloride or vinylidene chloride copolymers, starch, polysaccharides such as cellulose, and the like.

[0314] Then, such a second polyurethane dispersion is applied to the surface of the first polyurethane layer 3 and dried, thereby forming the second polyurethane layer 6.

[0315] More specifically, to form the second polyurethane layer 6, the concentration of the second polyurethane dispersion is adjusted by the above-mentioned method to prepare a second coating agent (second coating liquid), and the obtained second coating agent is applied onto the first polyurethane layer 3 and dried.

[0316] Furthermore, in order to impart wettability to the first polyurethane layer 3 or to dilute the coating agent, for example, the above-mentioned mono-ol can be added in the above-mentioned ratio to the second coating agent.

[0317] The solids concentration of the second coating agent is, for example, 0.5 mass % or more, preferably 1 mass % or more, and for example, 30 mass % or less, preferably 25 mass % or less.

[0318] The method for applying the second coating agent is not particularly limited, and may be the same as the above.

[0319] The drying conditions are such that the drying temperature is, for example, 40° C. or more, preferably 50° C. or more, more preferably 80° C. or more, and for example, 200° C. or less, preferably 180° C. or less, more preferably 150° C. or less, and the drying time is, for example, 0.1 minutes or more, preferably 0.2 minutes or more, and for example, 10 minutes or less, preferably 5 minutes or less.

[0320] This allows the second polyurethane layer 6 made of the second polyurethane resin to be formed on the first polyurethane layer 3.

[0321] Furthermore, in the laminate 1, a layered inorganic compound can also be dispersed in the second polyurethane layer 6 in order to improve the gas barrier properties.

[0322] The thickness of the second polyurethane layer 6 is, for example, 0.05 g / m2 as the lamination amount of the second polyurethane resin (after drying). 2 More than 0.1 g / m 2 More preferably, 0.2 g / m 2 or more, for example, 10 g / m 2 Preferably, 7 g / m or less 2 Less than 5 g / m 2 More preferably, 3 g / m or less 2 More preferably, 2 g / m or less 2 Below, particularly preferably 1 g / m 2 The following is the result.

[0323] Then, as described above, a polyurethane layer 3 is formed on the inorganic layer 4 of the substrate 2, and then a second polyurethane layer 6 is formed on the first polyurethane layer 3, thereby obtaining a laminate 1 in which the substrate 2 (inorganic layer 4), the first polyurethane layer 3 and the second polyurethane layer 6 are laminated in sequence.

[0324] The laminate 1 has a thickness of, for example, 5 μm or more, preferably 10 μm or more, and for example, 1 mm or less, preferably 0.5 mm or less.

[0325] If necessary, the obtained laminate 1 may be aged, for example, at 30 to 60° C. for about 2 to 5 days.

[0326] The laminate 1 thus obtained also comprises the above-mentioned polyurethane layer 3 , and also comprises an inorganic layer 4 disposed so as to be in contact with one surface of the polyurethane layer 3 .

[0327] In other words, in such a laminate 1, the dried product of the above-mentioned polyurethane dispersion is laminated onto the inorganic layer 4, so that deformation and deterioration of the first polyurethane layer 3 due to high-temperature sterilization treatment (retort treatment) can be suppressed, and the gas barrier properties are excellent even after the high-temperature sterilization treatment (retort treatment).

[0328] Furthermore, in the laminate 1, the second polyurethane layer 6 is further formed on the first polyurethane layer 3, and therefore it is possible to develop particularly excellent gas barrier properties.

[0329] Furthermore, since the second polyurethane layer 6 ensures gas barrier properties, the formulation of the first polyurethane layer 3 can be designed with an emphasis on suppressing deformation and deterioration due to high-temperature sterilization treatment (retort treatment).

[0330] As a result, it is possible to achieve a particularly good balance between gas barrier properties and resistance to high-temperature sterilization treatment (retort treatment).

[0331] In the above description, the first polyurethane layer 3 (and the second polyurethane layer 6 which is laminated as required) is laminated only on the surface of the substrate 2; however, for example, although not shown, the first polyurethane layer 3 (and the second polyurethane layer 6 which is laminated as required) may be laminated on both the front and back surfaces of the substrate 2, and further, may be laminated over the entire surface of the front and / or back surface of the substrate 2, or may be laminated only on a portion of the surface.

[0332] Since such a laminate 1 has excellent gas barrier properties and resistance to high-temperature sterilization treatment (retort treatment), it can be laminated with the above-mentioned thermoplastic resin film (e.g., unstretched polypropylene film, etc.) as necessary to be suitably used in various packaging applications requiring gas barrier properties, specifically, packaging films for food and medicine, food packaging containers (including bottles), optical films, industrial films, etc., and is particularly suitably used as a food packaging film for contents that require high-temperature sterilization treatment such as boiling sterilization and retort sterilization, and heat treatment such as cooking.

[0333] In addition, the above-mentioned coating agent or hybrid coating agent can be mixed with a colorant such as a pigment to prepare a printing ink, which can be applied to plastic films, paper, various containers, etc., and can also be suitably used as a printed film or printed body. EXAMPLES

[0334] Next, the present invention will be described based on examples and comparative examples, but the present invention is not limited thereto. Note that "parts" and "%" are based on mass unless otherwise specified. In addition, the specific numerical values ​​of the blending ratio (content ratio), physical property values, parameters, etc. used in the following description can be replaced with the upper limit value (a numerical value defined as "less than or equal to" or "less than") or lower limit value (a numerical value defined as "more than or equal to" or "exceeding") of the corresponding blending ratio (content ratio), physical property values, parameters, etc. described in the above "Form for carrying out the invention".

[0335] 1. The polyurethane layer is a single layer. <Preparation of Polyurethane Dispersion (PUD-A)> Reference examples 1~3 and Comparative Examples 1 to 6 (PUD-A1 to A9) According to the formulation shown in Table 1, a polyisocyanate component, a polyol component, and methyl ethyl ketone (MEK) as a solvent were mixed and reacted under a nitrogen atmosphere at 65 to 70°C until a predetermined NCO% (2 to 11%) was reached, to obtain a reaction liquid containing an isocyanate-terminated prepolymer.

[0336] Next, the resulting reaction solution was cooled to 40° C., and then neutralized with triethylamine (TEA).

[0337] The reaction solution was then dispersed in ion-exchanged water using a homodisper, and an aqueous amine solution prepared by dissolving 2-((2-aminoethyl)amino)ethanol in ion-exchanged water was added as a chain extender. Furthermore, N-2-(aminoethyl)-3-aminopropyltrimethoxysilane (trade name: KBM-603, manufactured by Shin-Etsu Chemical Co., Ltd.) was added as a chain extender as necessary.

[0338] Thereafter, the reaction was carried out for 1 hour, and methyl ethyl ketone and ion-exchanged water were distilled off using an evaporator. The solid content was adjusted to 25% by mass with ion-exchanged water, thereby obtaining Polyurethane Dispersions-A1 to A9 (PUD-A1 to A9).

[0339] The total urethane group concentration and urea group concentration calculated by charging calculation are shown in Table 1.

[0340] [Table 1]

[0341] Details of the abbreviations in the table are given below. m-XDI: Takenate 500, 1,3-xylylene diisocyanate, m-XDI, manufactured by Mitsui Chemicals (non-carbon ring-directed NCO compound) IPDI: Vestanat IPDI, isophorone diisocyanate, IPDI, manufactured by Evonik (NCO compound directly bonded to a carbon ring) TDI: Cosmonate T-80, 2,4-tolylene diisocyanate, TDI, manufactured by Mitsui Chemicals (NCO compound directly bonded to a carbon ring) H6XDI: Takenate 600, 1,3-bis(isocyanatomethyl)cyclohexane, 1,3-H6XDI, manufactured by Mitsui Chemicals (non-carbon ring-directed NCO compound) NBDI: Bis(isocyanatomethyl)norbornane, NBDI, manufactured by Mitsui Chemicals (non-carbon ring-directed NCO compound) H12MDI:VestanatH 12 MDI, 4,4'-methylenebis(cyclohexyl isocyanate, Evonik (NCO compound directly bonded to a carbon ring) EG: Ethylene glycol TMP: Trimethylolpropane DMPA: Dimethylolpropionic acid U-7020: Takelac U-7020, polyester polyol, number average molecular weight 2000, manufactured by Mitsui Chemicals U-9025: Takelac U-9025 (polyester polyol, number average molecular weight 2500, manufactured by Mitsui Chemicals, Inc. MEK: Methyl ethyl ketone TEA: Triethylamine AEA: 2-((2-aminoethyl)amino)ethanol KBM-603: N-2-(aminoethyl)-3-aminopropyltrimethoxysilane (product name: KBM-603, manufactured by Shin-Etsu Chemical Co., Ltd.) <Preparation of coating solution> Preparation Examples 1 to 21 (Coating Agents A1 to A21) According to the recipes shown in Tables 2 and 3, polyurethane dispersions (PUD) were mixed with a magnetic stirrer, ion-exchanged water and isopropanol were gradually added thereto, and a crosslinking agent was further added and stirred as necessary. Coating agents A1 to A21 were thus obtained.

[0342] [Table 2]

[0343] [Table 3]

[0344] Details of the abbreviations in the table are given below. IPA: Isopropanol Takenate WD-726: Water-dispersible polyisocyanate (crosslinking agent), solids concentration 80% by mass, manufactured by Mitsui Chemicals KBM-403: 3-glycidoxypropyltrimethoxysilane (crosslinking agent), manufactured by Shin-Etsu Chemical Co., Ltd. Carbodilite V-02: Polycarbodiimide compound (crosslinking agent), manufactured by Nisshinbo Chemical Co., Ltd. <Creating a laminate> Example 4 11, Reference example 12 and Comparative Examples 7 to 18 ·Laminates-A1~A21 According to the formulations shown in Tables 4 and 5, the coating agent obtained in each preparation example was applied to the alumina-deposited surface of an alumina-deposited PET film (Barrierox 1011HG (#12), manufactured by Toray Advanced Film Co., Ltd.) as a substrate in a dry thickness of 0.5 g / m.2 The substrate was then placed in a drying oven set at 110°C and dried for 1 minute to form a polyurethane layer on the alumina deposition surface of the substrate. The substrate was then left to cure at 50°C for 2 days.

[0345] As a result, laminates A1 to A21 were obtained in which a polyurethane layer was laminated on the alumina-deposited surface of the substrate.

[0346] <<Evaluation>> <Creating laminate film> A mixture of Takelac A-310 (manufactured by Mitsui Chemicals) and Takenate A-3 (manufactured by Mitsui Chemicals) was applied as a dry lamination adhesive to the polyurethane layer of each laminate to a dry thickness of 3 g / m. 2 The coating was applied using a bar coater so that the coating became smooth, and then dried using a dryer.

[0347] Thereafter, an unstretched polypropylene film (Tocello CP RXC-22 (CPP film, #60), manufactured by Mitsui Chemicals Tocello Co., Ltd.) was laminated onto each laminate via the above adhesive, and cured at 40° C. for 3 days to obtain a laminate film.

[0348] <Hot water sterilization (retort) test> The laminate film was sterilized with hot water at 120°C for 30 minutes under a pressure of 0.2 MPa. The appearance was then visually evaluated to confirm the presence or absence of whitening. Those that did not show whitening were rated as "○".

[0349] <Measurement of adhesion (lamination strength)> For each laminate film before and after the retort test, the lamination strength between the substrate (alumina vapor-deposited surface) and the polyurethane layer of each laminate was measured by a T-peel test (15 mm width) in accordance with JIS K 6854. If the alumina vapor-deposited PET film was cut during the measurement, it was marked as "MF."

[0350] <Oxygen transmission rate (OTR) measurement> For each laminate film before and after the retort test, oxygen permeability was measured at 20°C and 80% relative humidity (80% RH) using an oxygen permeability measuring device (OX-TRAN2 / 20, manufactured by MOCON). 2 The oxygen transmission rate (OTR) per day and per atmosphere was measured.

[0351] In addition, the rate of change in OTR before and after the retort test (OTR after retort test / OTR before retort test) was calculated.

[0352] [Table 4]

[0353] [Table 5]

[0354] 2. Two polyurethane layers <Preparation of Polyurethane Dispersion (PUD)> reference Examples 13 to 15 and Comparative Examples 19 to 20 (PUD-B1 to B5) According to the formulation shown in Table 6, a polyisocyanate component, a polyol component, and methyl ethyl ketone (MEK) or acetonitrile as a solvent were mixed and reacted under a nitrogen atmosphere at 65 to 70°C until a predetermined NCO% (6 to 11% or less) was reached, to obtain a reaction liquid containing an isocyanate-terminated prepolymer.

[0355] Next, the resulting reaction solution was cooled to 40° C., and then neutralized with triethylamine (TEA).

[0356] The reaction solution was then dispersed in ion-exchanged water using a homodisper, and an aqueous amine solution prepared by dissolving 2-((2-aminoethyl)amino)ethanol in ion-exchanged water was added as a chain extender. Furthermore, N-2-(aminoethyl)-3-aminopropyltrimethoxysilane (trade name: KBM-603, manufactured by Shin-Etsu Chemical Co., Ltd.) was added as a chain extender as necessary.

[0357] Thereafter, the reaction was carried out for 1 hour, and methyl ethyl ketone and ion-exchanged water were removed by distillation using an evaporator. The solid content was adjusted to 25% by mass with ion-exchanged water, thereby obtaining Polyurethane Dispersions-B1 to B5 (PUD-B1 to B5).

[0358] The total urethane group concentration and urea group concentration calculated by charging calculation are shown in Table 6.

[0359] [Table 6]

[0360] The abbreviations in the table are the same as above.

[0361] <Preparation of coating solution> Preparation Examples 22 to 35 (Coating Agents B1 to B14) According to the recipes shown in Tables 7 and 8, polyurethane dispersions (PUD) were mixed with a magnetic stirrer, and ion-exchanged water and isopropanol were gradually added thereto, and further, a crosslinking agent was added as necessary and stirred. Thus, coating agents B1 to B14 were obtained.

[0362] [Table 7]

[0363] [Table 8]

[0364] The abbreviations in the table are the same as above.

[0365] In the table, Bhydur 3100 refers to a water-dispersible polyisocyanate (crosslinking agent, Bayhydur 3100, manufactured by Bayer).

[0366] <Creating a laminate> referenceExamples 16 to 23 and Comparative Examples 21 to 31 ·Laminated body-B1~B19 According to the formulations shown in Tables 9 and 10, the coating agent obtained in each preparation example was applied to the alumina-deposited surface of an alumina-deposited PET film (Barrierox 1011HG (#12), manufactured by Toray Advanced Film Co., Ltd.) as a substrate in a dry thickness of 0.5 g / m. 2 The substrate was then placed in a drying oven set at 110°C and dried for 1 minute to form a first polyurethane layer on the alumina vapor deposition surface of the substrate. The substrate was then cured at 50°C for 2 days.

[0367] Furthermore, according to the formulations shown in Tables 9 and 10, the coating agent obtained in each preparation example was applied to the surface of the first polyurethane layer to a dry thickness of 0.5 g / m 2 The coated layer was then placed in a drying oven set at 110°C and dried for 1 minute to form a second polyurethane layer on the surface of the first polyurethane layer. The coated layer was then left to cure at 50°C for 2 days.

[0368] As a result, a first polyurethane layer was laminated on the alumina-deposited surface of the substrate, and further, a second polyurethane layer was laminated on the first polyurethane layer, thereby obtaining laminates B1 to B19.

[0369] <<Evaluation>> <Creating laminate film> A mixture of Takelac A-310 (manufactured by Mitsui Chemicals) and Takenate A-3 (manufactured by Mitsui Chemicals) was applied as a dry lamination adhesive to the polyurethane layer of each laminate to a dry thickness of 3 g / m. 2 The coating was applied using a bar coater so that the coating became smooth, and then dried using a dryer.

[0370] Thereafter, an unstretched polypropylene film (Tocello CP RXC-22 (CPP film, #60), manufactured by Mitsui Chemicals Tocello Co., Ltd.) was laminated onto each laminate via the above adhesive, and cured at 40° C. for 3 days to obtain a laminate film.

[0371] <Hot water sterilization (retort) test> The laminate film was subjected to hot water sterilization treatment at 120° C. for 30 minutes under a pressure of 0.2 MPa.

[0372] <Measurement of adhesion (lamination strength)> For each laminate film before and after the retort test, the lamination strength between the substrate (alumina vapor-deposited surface) and the first polyurethane layer of each laminate was measured by a T-peel test (15 mm width) in accordance with JIS K 6854. If the alumina vapor-deposited PET film was cut during the measurement, it was marked as "MF".

[0373] <Oxygen transmission rate (OTR) measurement> For each laminate film before and after the retort test, oxygen permeability was measured at 20°C and 80% relative humidity (80% RH) using an oxygen permeability measuring device (OX-TRAN2 / 20, manufactured by MOCON). 2 The oxygen transmission rate (OTR) per day and per atmosphere was measured.

[0374] In addition, the rate of change in OTR before and after the retort test (OTR after retort test / OTR before retort test) was calculated.

[0375] [Table 9]

[0376] [Table 10]

[0377] The above invention is provided as an exemplary embodiment of the present invention, but this is merely an example and should not be interpreted as being limited. Modifications of the present invention that are obvious to those skilled in the art are included in the scope of the following claims. [Industrial Applicability]

[0378] The polyurethane dispersion and laminate of the present invention are suitably used for, for example, packaging films for food and medicine, food packaging containers (including bottles), optical films, industrial films, and the like. [Explanation of symbols]

[0379] 1. Laminate 2 Base material 3 Polyurethane layer

Claims

1. A method for producing a coating composition comprising: a first polyurethane layer including a dried polyurethane dispersion; and an inorganic layer disposed in contact with at least one surface of the first polyurethane layer; The polyurethane dispersion is a polyurethane dispersion obtained by dispersing a polyurethane resin in water, The polyurethane resin is a reaction product obtained by reacting at least a polyisocyanate component with an active hydrogen group-containing component, The polyisocyanate component is A polyisocyanate compound having a carbon ring and at least one isocyanate group directly bonded to the carbon ring is contained in a proportion of 90 mass% or more based on the total amount of the polyisocyanate component, The polyisocyanate compound contains isophorone diisocyanate, The active hydrogen group-containing component contains a polyol component, The polyol component contains a diol having 2 to 4 carbon atoms, an active hydrogen group-containing compound containing a hydrophilic group, and a trivalent or higher low molecular weight polyol, the ratio of the diol having 2 to 4 carbon atoms is 30 parts by mass or more and 80 parts by mass or less with respect to 100 parts by mass of the total amount of the polyol component; A laminate comprising:

2. The polyurethane dispersion further contains a crosslinking agent.

2. The laminate according to claim 1 .

3. The inorganic layer contains aluminum oxide and / or silicon oxide.

2. The laminate according to claim 1 .

4. a second polyurethane layer including a dried product of a second polyurethane dispersion containing a second polyurethane resin on a surface of the first polyurethane layer opposite to the surface of the first polyurethane layer in contact with the inorganic layer, The second polyurethane resin is a reaction product obtained by reacting at least a second polyisocyanate component containing xylylene diisocyanate and / or hydrogenated xylylene diisocyanate with a second active hydrogen group-containing component containing a diol having 2 to 4 carbon atoms and an active hydrogen group-containing compound containing a hydrophilic group.

2. The laminate according to claim 1 .

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