JP7461171B2 - Polyurethane Laminate - Google Patents

Description

The present invention relates to a polyurethane laminate, and more specifically, to a polyurethane laminate having gas barrier properties.

As a film with excellent gas barrier properties, for example, a gas barrier composite film having a base film layer and a polyurethane layer obtained by applying a gas barrier polyurethane dispersion to the base film layer and drying it has been proposed. It has also been proposed to disperse a layered inorganic compound in the polyurethane layer in order to improve the gas barrier properties.

More specifically, such a gas barrier composite film includes a base material, a first layer laminated on the base material and made of a first polyurethane resin, and a layered inorganic compound laminated on the first layer. A polyurethane laminate has been proposed, comprising a second layer comprising a second polyurethane resin having a second polyurethane resin dispersed therein. Further, in the polyurethane laminate, an isocyanate obtained by reacting each of the first polyurethane resin and the second polyurethane resin with at least xylylene diisocyanate and/or hydrogenated xylylene diisocyanate and a diol having 2 to 6 carbon atoms. It has been proposed to generate it by reacting a group-terminated prepolymer with a chain extender containing a polyamine (see, for example, Patent Document 1).

Japanese Patent Application Publication No. 2015-44396

However, the film described in Patent Document 1 has a first layer laminated to the substrate that is a polyurethane layer with gas barrier properties, and therefore may not have sufficient adhesion. In particular, when a polyolefin film is used as the substrate, the substrate and the first layer may peel off.

The present invention is a polyurethane laminate that has excellent gas barrier properties and also has excellent adhesion to polyolefin substrates.

The present invention [1] includes a polyolefin base material, a first layer laminated on the polyolefin base material and made of a first polyurethane resin, and a second layer laminated on the first layer and made of a second polyurethane resin. The first polyurethane resin is a reaction product of a first isocyanate group-terminated prepolymer, which is a reaction product of a first isocyanate component and a first polyol component, and a first chain extender containing a polyamine. The first polyol component contains a polyester polyol having a number average molecular weight of 500 or more and an active hydrogen group-containing compound containing a hydrophilic group, and the second polyurethane resin contains a second isocyanate component and a second It is a reaction product of a second isocyanate group-terminated prepolymer, which is a reaction product of a polyol component, and a second chain extender containing a polyamine, and the second isocyanate component is xylylene diisocyanate and/or hydrogenated xylylene diisocyanate. The second polyol component contains a polyurethane laminate containing an isocyanate, a diol having 2 to 6 carbon atoms, and an active hydrogen group-containing compound containing a hydrophilic group.

The present invention [2] includes the polyurethane laminate described in [1] above, in which the active hydrogen group-containing compound containing a hydrophilic group in the first polyol component is an active hydrogen group-containing compound containing a nonionic group.

The present invention [3] includes the polyurethane laminate described in [2] above, in which the nonionic group is a polyoxyethylene group, and the content of the oxyethylene is 5% by mass or more and 40% by mass or less relative to the total amount of the first polyurethane resin.

The present invention [4] provides the polyurethane according to the above [1], wherein the active hydrogen group-containing compound containing a hydrophilic group in the first polyol component is an active hydrogen group-containing compound containing an anionic group. Contains a laminate.

The present invention [5] includes the polyurethane laminate according to any one of [1] to [4] above, in which the polyester polyol having a number average molecular weight of 500 or more in the first polyol component is a reaction product of a polybasic acid including an aromatic polycarboxylic acid and a polyhydric alcohol, and the content of the aromatic polycarboxylic acid relative to the total amount of the polybasic acid is 15 mass% or more.

The present invention [6] includes the polyurethane laminate described in any one of [1] to [5] above, in which the first isocyanate component contains an alicyclic polyisocyanate.

The present invention [7] includes the polyurethane laminate described in any one of [1] to [6] above, in which the first layer is an anchor coat layer.

The polyurethane laminate of the present invention has excellent gas barrier properties and also has excellent adhesion to polyolefin substrates.

FIG. 1 is a schematic diagram showing an embodiment of the polyurethane laminate of the present invention.

In FIG. 1, the polyurethane laminate 1 includes a polyolefin substrate 2, a first layer 3 laminated (placed) on the polyolefin substrate 2, and a second layer 4 laminated (placed) on the first layer 3.

The polyolefin substrate 2 is a substrate containing a polyolefin resin (e.g., polyethylene, polypropylene, propylene-ethylene copolymer, etc.). Examples of the substrate include substrates such as films, sheets, bottles, and cups. Preferably, the substrate is a film.

More specifically, the polyolefin base material 2 includes, for example, a film made of polyolefin resin (polyolefin film). Note that the polyolefin base material 2 may be a single-layer base material, or may be a base material (laminate) having multiple layers.

The polyolefin substrate 2 may be a non-oriented substrate, a uniaxially oriented substrate, or a biaxially oriented substrate. The polyolefin substrate 2 may be surface-treated (corona discharge treatment, etc.).

The polyolefin substrate 2 is preferably a biaxially oriented polyolefin film, and more preferably a biaxially oriented polypropylene film (OPP).

The thickness of the polyolefin base material 2 is, for example, 3 μm or more, preferably 5 μm or more, and is, for example, 500 μm or less, preferably 200 μm or less.

The first layer 3 is a polyurethane layer made of a first polyurethane resin.

The first polyurethane resin is a reaction product of a first isocyanate group-terminated prepolymer, which is a reaction product of a first isocyanate component and a first polyol component, and a first chain extender containing a polyamine.

From the viewpoint of manufacturing efficiency, the first layer 3 is preferably formed by applying a polyurethane dispersion (first dispersion) containing the first polyurethane resin to the polyolefin substrate 2 and drying it.

To prepare a polyurethane dispersion (first dispersion) containing a first polyurethane resin, the first polyurethane resin is synthesized as an aqueous polyurethane resin, and the resulting aqueous polyurethane resin is dispersed in water.

More specifically, in this method, for example, a first isocyanate component and a first polyol component are reacted to synthesize a first isocyanate group-terminated prepolymer.

The first isocyanate component is a component having a free isocyanate group, and includes, for example, a polyisocyanate monomer, a polyisocyanate derivative, and the like.

Examples of the polyisocyanate monomer include aromatic polyisocyanates, araliphatic polyisocyanates, and aliphatic polyisocyanates.

Examples of aromatic polyisocyanates include 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 mixtures thereof) (MDI), Examples include aromatic diisocyanates such as 4,4'-toluidine diisocyanate (TODI) and 4,4'-diphenyl ether diisocyanate.

Examples of aromatic aliphatic polyisocyanates include aromatic aliphatic diisocyanates such as xylylene diisocyanate (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'-diisocyanate-1,4-diethylbenzene.

Examples of aliphatic polyisocyanates 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 (HDI), 2,4,4- or 2,2,4-trimethylhexamethylene diisocyanate, and 2,6-diisocyanate methyl caproate.

Furthermore, aliphatic polyisocyanates include alicyclic polyisocyanates. Examples of alicyclic polyisocyanates include 1,3-cyclopentane diisocyanate, 1,3-cyclopentene diisocyanate, cyclohexane diisocyanate (1,4-cyclohexane diisocyanate, 1,3-cyclohexane diisocyanate), and isophorone diisocyanate (IPDI, 3-cyclohexane diisocyanate). isocyanatomethyl-3,5,5-trimethylcyclohexyl isocyanate), methylene bis(cyclohexyl isocyanate) (4,4'-, 2,4'- or 2,2'-methylene bis(cyclohexyl isocyanate, Trans, Trans-isocyanate) , Trans, Cis-form, Cis, Cis-form, or a mixture thereof)) (H ₁₂ MDI), methylcyclohexane diisocyanate (methyl-2,4-cyclohexane diisocyanate, methyl-2,6-cyclohexane diisocyanate), norbornane diisocyanate ( Alicyclic diisocyanates such as various isomers or mixtures thereof) (NBDI), bis(isocyanatomethyl)cyclohexane (1,3- or 1,4-bis(isocyanatomethyl)cyclohexane or mixtures thereof) (H ₆ XDI) can be mentioned.

These polyisocyanate monomers can be used alone or in combination of two or more. Preferable examples of the polyisocyanate monomer include alicyclic polyisocyanates.

Examples of polyisocyanate derivatives include multimers (e.g., dimers, trimers, pentamers, heptamers, etc.) of the above-mentioned polyisocyanate monomers (e.g., isocyanurate derivatives, iminooxadiazinedione derivatives). )), allophanate derivatives (e.g., allophanate derivatives produced by the reaction of the above-mentioned polyisocyanate monomers with known monohydric alcohols or dihydric alcohols (described later)), polyol derivatives (e.g., polyisocyanate monomers) and polyol derivatives (alcohol adducts) produced by the reaction with trihydric or higher alcohols (described later), biuret derivatives (e.g., produced by the reaction of the above-mentioned polyisocyanate monomer with water or amines) biuret derivatives, etc.), urea derivatives (e.g., urea derivatives produced by the reaction of the above-mentioned polyisocyanate monomers with diamines), oxadiazinetrione derivatives (e.g., the reaction between the above-mentioned polyisocyanate monomers and carbon dioxide), Examples include oxadiazinetrione produced by the reaction), carbodiimide derivatives (carbodiimide derivatives produced by the above-described decarboxylation condensation reaction of polyisocyanate monomers, etc.), uretdione derivatives, uretonimine derivatives, and the like.

Further examples of polyisocyanate derivatives include polymethylene polyphenyl polyisocyanate (crude MDI, polymeric MDI, polynuclear-containing diphenylmethane diisocyanate).

These polyisocyanate derivatives can be used alone or in combination of two or more.

The first isocyanate component may contain a polyisocyanate monomer alone, may contain a polyisocyanate derivative alone, or may contain both a polyisocyanate monomer and a polyisocyanate derivative. Preferably, the first isocyanate component contains a polyisocyanate monomer alone.

The first isocyanate component is preferably an aliphatic polyisocyanate or an aromatic polyisocyanate, more preferably an aliphatic polyisocyanate, even more preferably an alicyclic polyisocyanate, and particularly preferably an aliphatic polyisocyanate. , isophorone diisocyanate.

The first polyol component contains a high molecular weight polyol as an essential component.

The high molecular weight polyol is a compound having two or more hydroxyl groups and a number average molecular weight of 400 or more, preferably 500 or more, for example, 10,000 or less.

The high molecular weight polyol contains at least a polyester polyol having a number average molecular weight of 500 or more. In other words, the first polyol component contains a polyester polyol having a number average molecular weight of 500 or more.

A polyester polyol having a number average molecular weight of 500 or more can be obtained, for example, as a polycondensate of a polybasic acid and a polyhydric alcohol.

Examples of the polybasic acid include aliphatic polycarboxylic acids, aromatic polycarboxylic acids, and other carboxylic acids.

Examples of aliphatic polycarboxylic acids include saturated aliphatic polycarboxylic acids such as oxalic acid, malonic acid, succinic acid, methylsuccinic acid, glutaric acid, adipic acid, 1,1-dimethyl-1,3-dicarboxypropane, 3-methyl-3-ethylglutaric acid, azelaic acid, and sebacic acid; unsaturated aliphatic dicarboxylic acids such as maleic acid, fumaric acid, and itaconic acid; and alicyclic dicarboxylic acids such as hexahydrophthalic acid. These may be used alone or in combination of two or more kinds. Examples of aliphatic polycarboxylic acids include preferably adipic acid and sebacic acid, and more preferably sebacic acid.

Examples of the aromatic polycarboxylic acid include aromatic dicarboxylic acids such as orthophthalic acid, isophthalic acid, terephthalic acid, toluene dicarboxylic acid, and naphthalene dicarboxylic acid. These can be used alone or in combination of two or more. Preferably, the aromatic polycarboxylic acid is isophthalic acid.

Examples of other carboxylic acids include dimer acid, hydrogenated dimer acid, and het acid. These can be used alone or in combination of two or more.

Furthermore, as polybasic acids, acid anhydrides (for example, oxalic anhydride, succinic anhydride, maleic anhydride) derived from the above carboxylic acids (aliphatic polycarboxylic acids, aromatic polycarboxylic acids, and other carboxylic acids) acids, phthalic anhydride, 2-alkyl (C12-C18) succinic anhydride, tetrahydrophthalic anhydride, trimellitic anhydride, etc.) and acid halides derived from the above carboxylic acids (for example, oxalic acid dichloride, adipine acid dichloride, sebacic acid dichloride, etc.). These can be used alone or in combination of two or more.

These polybasic acids can be used alone or in combination of two or more types.

From the viewpoint of adhesion, the polybasic acid preferably contains an aromatic polycarboxylic acid. The polybasic acid more preferably contains an aliphatic polycarboxylic acid and an aromatic polycarboxylic acid, even more preferably contains an aliphatic dicarboxylic acid and an aromatic dicarboxylic acid, and particularly preferably consists of an aliphatic dicarboxylic acid and an aromatic dicarboxylic acid.

When the polybasic acid contains an aromatic polycarboxylic acid, from the viewpoint of adhesion, the content ratio of the aromatic polycarboxylic acid to the total amount of the polybasic acid is, for example, 5% by mass or more, preferably 15% by mass or more. % by mass or more, more preferably 30% by mass or more, still more preferably 40% by mass or more, for example, 100% by mass or less, preferably 90% by mass or less, more preferably 70% by mass or less, even more preferably is 50% by mass or less. Note that the content ratio of the aromatic polycarboxylic acid can also be adjusted to an appropriate value, for example, by mixing multiple types of polyester polyols.

Polyhydric alcohols are compounds that have two or more hydroxyl groups in their molecules. Examples of polyhydric alcohols include ethylene glycol, propylene glycol, 1,3-propanediol, 1,4-butylene glycol, 1,3-butylene glycol, 1,2-butylene glycol, 1,5-pentanediol, neo Pentyl glycol, 1,6-hexanediol, 3-methyl-1,5-pentanediol, 2,2,2-trimethylpentanediol, 3,3-dimethylolheptane, alkane (C7-20) diol, 1,3 - or 1,4-cyclohexanedimethanol and mixtures thereof, 1,3- or 1,4-cyclohexanediol and mixtures thereof, hydrogenated bisphenol A, 1,4-dihydroxy-2-butene, 2,6-dimethyl -1-octene-3,8-diol, bisphenol A, dihydric alcohols such as diethylene glycol, triethylene glycol, dipropylene glycol, trihydric alcohols such as glycerin, trimethylolpropane, triisopropanolamine, e.g. tetramethylol Tetrahydric alcohols such as methane (pentaerythritol), diglycerin, pentahydric alcohols such as xylitol, hexahydric alcohols such as sorbitol, mannitol, allitol, iditol, dulcitol, altritol, inositol, dipentaerythritol, e.g. , heptahydric alcohols such as perseitol, and octahydric alcohols such as sucrose.

These polyhydric alcohols can be used alone or in combination of two or more.

As the polyhydric alcohol, from the viewpoint of adhesion and gas barrier properties, preferably, a dihydric alcohol is used, and more preferably, ethylene glycol, neopentyl glycol, 1,6-hexanediol, and a combination of two or more of these are used. When two or more types are used in combination, the ratio of the combination is appropriately set according to the purpose and application.

In the production of polyester polyol, for example, a polybasic acid and a polyhydric alcohol are mixed and heated in the presence of a known ester catalyst and organic solvent to cause a dehydration condensation reaction. In such a reaction, the reaction recipe and reaction conditions are appropriately set so that the number average molecular weight of the resulting polyester polyol falls within the range described below.

The ratio of polybasic acid to polyhydric alcohol is, for example, 0.8 moles or more, preferably 0.9 moles or more, and for example, 1.2 moles or less, preferably 1.1 moles or less, of hydroxyl groups of the polyhydric alcohol per mole of carboxyl groups of the polybasic acid. The reaction temperature is, for example, 100°C or more, preferably 150°C or more, and for example, 300°C or less, preferably 250°C or less. The reaction time is, for example, 1 hour or more, preferably 10 hours or more, and for example, 30 hours or less, preferably 20 hours or less.

This results in a polyester polyol, which is a polycondensation product of a polybasic acid and a polyhydric alcohol.

In addition, examples of the polyester polyol include polycondensates of polybasic acids and polyhydric alcohols, as well as polyester polyols derived from plants.

Examples of plant-derived polyester polyols include vegetable oil-based polyester polyols obtained by condensing hydroxycarboxylic acids such as hydroxyl group-containing vegetable oil fatty acids (e.g., castor oil fatty acids containing ricinoleic acid, hydrogenated castor oil fatty acids containing 12-hydroxystearic acid, etc.) under known conditions using the above-mentioned polyhydric alcohols as initiators.

Furthermore, examples of polyester polyols include lactone-based polyester polyols. Lactone-based polyester polyols are produced by using, for example, the above-mentioned polyhydric alcohol (preferably dihydric alcohol) as an initiator, and lactones such as ε-caprolactone and γ-valerolactone, for example, L-lactide and D-lactone. It can be obtained by ring-opening polymerization of lactides such as lactide. Specific examples of the lactone-based polyester polyol include polycaprolactone polyol, polyvalerolactone polyol, and further include copolymerized lactone-based polyester polyols obtained by copolymerizing them with the above-mentioned polyhydric alcohols.

Preferably, the polyester polyol includes a polycondensate of a polybasic acid and a polyhydric alcohol, and/or a lactone polyester polyol, and more preferably a polycondensate of a polybasic acid and a polyhydric alcohol. It will be done.

The number average molecular weight of the polyester polyol (number average molecular weight measured by GPC using standard polystyrene as a calibration curve) is 500 or more, preferably 800 or more, more preferably 1000 or more, even more preferably 1500 or more, and particularly preferably 1800 or more, and is, for example, 10000 or less, preferably 8000 or less, more preferably 6000 or less, even more preferably 4000 or less, and particularly preferably 2500 or less.

The hydroxyl value of the polyester polyol (based on JIS K 1557-1 (2007) Method A or B) is, for example, 30 mgKOH/g or more, preferably 56 mgKOH/g or more, and, for example, 300 mgKOH/g or less, preferably 100 mgKOH/g or less.

Moreover, the high molecular weight polyol can also contain high molecular weight polyols (hereinafter referred to as other high molecular weight polyols) other than the above-mentioned polyester polyols as an optional component.

Other high molecular weight polyols include, for example, polyether polyols, polycarbonate polyols, polyurethane polyols, epoxy polyols, vegetable oil polyols, polyolefin polyols, acrylic polyols, and vinyl monomer modified polyols.

Examples of polyether polyols include polyoxyalkylene polyols and polytetramethylene ether polyols.

Polyoxyalkylene polyol is, for example, an addition polymer of alkylene oxide such as propylene oxide or ethylene oxide using the above-mentioned polyhydric alcohol or a known polyamine compound as an initiator.

Alkylene oxides can be used alone or in combination of two or more types.

Examples of the polyoxyalkylene polyol include polyoxyethylene glycol, polyoxypropylene glycol, and polyethylene polypropylene glycol (random or block copolymer).

Examples of polytetramethylene ether polyols include ring-opening polymers obtained by cationic polymerization of tetrahydrofuran, and amorphous (non-crystalline) polymers obtained by copolymerizing polymerized units such as tetrahydrofuran with alkyl-substituted tetrahydrofuran or the above dihydric alcohol. Polytetramethylene ether glycol, etc.

Amorphous (non-crystalline) means that it is liquid at room temperature (25°C).

Examples of polycarbonate polyols include ring-opening polymers of ethylene carbonate using the above-mentioned polyhydric alcohols (preferably dihydric alcohols) as initiators, and amorphous polycarbonate polyols obtained by copolymerizing the above-mentioned dihydric alcohols with the ring-opening polymers.

In addition, polyurethane polyols can be obtained as polyester polyurethane polyols, polyether polyurethane polyols, polycarbonate polyurethane polyols, or polyester polyether polyurethane polyols by reacting the above polyester polyols, polyether polyols, and/or polycarbonate polyols with polyisocyanates in such a ratio that the equivalent ratio (OH/NCO) of hydroxyl groups (OH) to isocyanate groups (NCO) exceeds 1.

Examples of epoxy polyols include those obtained by reacting the above-mentioned polyhydric alcohols with polyfunctional halohydrins such as epichlorohydrin and β-methylepichlorohydrin.

Examples of the vegetable oil polyol include hydroxyl group-containing vegetable oils such as castor oil and coconut oil. Examples include castor oil polyols and ester-modified castor oil polyols obtained by reacting castor oil fatty acids with polypropylene polyols.

Examples of polyolefin polyols include polybutadiene polyols and partially saponified ethylene-vinyl acetate copolymers.

Examples of the acrylic polyol include copolymers obtained by copolymerizing a hydroxyl group-containing acrylate and a copolymerizable vinyl monomer that is copolymerizable with the hydroxyl group-containing acrylate.

Furthermore, acrylic polyols include, for example, silicone polyols and fluorine polyols.

Examples of silicone polyols include modified polysiloxane polyols in which hydroxyl groups are introduced into dialkylpolysiloxanes, and examples of copolymerizable vinyl monomers used in copolymerization of the above-mentioned acrylic polyols, such as γ-methacryloxypropyltrimethoxysilane. Examples include acrylic polyols blended with silicone compounds containing vinyl groups.

An example of a fluorine polyol is an acrylic polyol that is blended with a fluorine compound containing a vinyl group, such as tetrafluoroethylene or chlorotrifluoroethylene, as a copolymerizable vinyl monomer in the copolymerization of the acrylic polyol described above.

The vinyl monomer modified polyol can be obtained by reacting the above-mentioned high molecular weight polyol with a vinyl monomer.

Other high molecular weight polyols can be used alone or in combination of two or more types.

The number average molecular weight (number average molecular weight measured by GPC using standard polystyrene as a calibration curve) of the other high molecular weight polyol is 500 or more, preferably 800 or more, more preferably 1000 or more, still more preferably 1500 or more, especially It is preferably 1,800 or more, for example, 10,000 or less, preferably 8,000 or less, more preferably 6,000 or less, still more preferably 4,000 or less, particularly preferably 2,500 or less.

The high molecular weight polyol preferably does not contain other high molecular weight polyols and is composed of the above-mentioned polyester polyol having a number average molecular weight of 500 or more.

The content ratio of the high molecular weight polyol (preferably a polyester polyol having a number average molecular weight of 500 or more) is, for example, 10 parts by mass or more, preferably 20 parts by mass or more, based on 100 parts by mass of the total amount of the first polyol component. Preferably, it is 50 parts by mass or more, for example, 95 parts by mass or less, preferably 90 parts by mass or less.

Moreover, the first polyol component contains an active hydrogen group-containing compound containing a hydrophilic group as an essential component.

An active hydrogen group-containing compound that contains a hydrophilic group is a compound that contains a hydrophilic group such as a nonionic group or an ionic group, and an active hydrogen group such as an amino group or a hydroxyl group. Specific examples of such compounds include active hydrogen group-containing compounds that contain a nonionic group, and active hydrogen group-containing compounds that contain an ionic group.

The active hydrogen group-containing compound containing a nonionic group contains a nonionic group and an active hydrogen group.

Examples of nonionic groups include polyoxyethylene groups.

Examples of the active hydrogen group-containing compound containing a polyoxyethylene group include polyoxyethylene glycol, one end-capped polyoxyethylene glycol, and a polyol containing a polyoxyethylene side chain.

Polyols containing polyoxyethylene side chains are compounds that contain polyoxyethylene groups in the side chains and have two or more hydroxyl groups, and can be synthesized as follows:

That is, first, the above-mentioned diisocyanate and one end-blocked polyoxyethylene glycol (for example, an alkoxypolyoxyethylene monool one end-blocked with an alkyl group having 1 to 4 carbon atoms, with a number average molecular weight of 200 to 6,000, preferably 300 to 3000) in a ratio such that the isocyanate groups of the diisocyanate are in excess of the hydroxyl groups of the one-end-blocked polyoxyethylene glycol, and if necessary, unreacted diisocyanate is removed to form polyoxyethylene glycol. An ethylene chain-containing monoisocyanate is obtained.

Next, the polyoxyethylene chain-containing monoisocyanate and a dialkanolamine (such as diethanolamine) are subjected to a urea-forming reaction in such a ratio that the amount of isocyanate groups of the polyoxyethylene group-containing monoisocyanate is approximately equal to the amount of secondary amino groups of the dialkanolamine.

As diisocyanates for obtaining polyols containing polyoxyethylene side chains, preference is given to aliphatic diisocyanates such as hexamethylene diisocyanate (HDI), 1,4- or 1,3-bis(isocyanatomethyl)cyclohexane (H ₆ XDI), 3-isocyanatomethyl-3,5,5-trimethylcyclohexyl isocyanate (also known as isophorone diisocyanate) (IPDI), 4,4'-methylenebis(cyclohexylisocyanate) (H ₁₂ MDI), 2,6-bis( Examples include alicyclic diisocyanates such as isocyanatomethyl)norbonane (NBDI).

These active hydrogen group-containing compounds containing nonionic groups can be used alone or in combination of two or more kinds. As the active hydrogen group-containing compound containing a nonionic group, a preferred example is an active hydrogen group-containing compound containing a polyoxyethylene group, and more preferably, a polyol containing a polyoxyethylene side chain.

By using a polyol containing polyoxyethylene side chains, the first polyurethane resin can be made to have a relatively high molecular weight, making it possible to obtain a first layer 3 that has excellent physical properties.

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, 400 or more, preferably 500 or more, more preferably 600 or more, and for example, 10,000 or less, preferably 8,000 or less, more preferably 6,000 or less.

An active hydrogen group-containing compound containing an ionic group includes, for example, an anionic group such as a carboxylic acid, a cationic group such as a quaternary amine, and two or more active hydrogen groups such as a hydroxyl group or an amino group. Preferably, compounds having both an anionic group and two or more hydroxyl groups (active hydrogen group-containing compounds containing an anionic group) are mentioned, and more preferably, compounds having a carboxylic acid and two or more hydroxyl groups. and (active hydrogen group-containing compounds containing carboxyl groups (for example, carboxyl group-containing polyols)).

Examples of carboxy group-containing polyols include 2,2-dimethylol acetic acid, 2,2-dimethylol lactic acid, 2,2-dimethylol propionic acid, 2,2-dimethylol butanoic acid, 2,2-dimethylol butyric acid, 2, Examples include polyhydroxyalkanoic acids such as 2-dimethylolvaleric acid. These can be used alone or in combination of two or more.

The active hydrogen group-containing compound containing an ionic group can be used alone or in combination of two or more kinds. As the active hydrogen group-containing compound containing an ionic group, preferably, an active hydrogen group-containing compound containing an anionic group is used, more preferably, a carboxy group-containing polyol is used, and particularly preferably, a polyhydroxyalkanoic acid is used.

The active hydrogen group-containing compound containing a hydrophilic group can be used alone or in combination.

From the viewpoint of adhesion, it is preferable to use a compound containing an active hydrogen group that contains a nonionic group alone as the active hydrogen group-containing compound that contains a hydrophilic group.

In other words, by using an active hydrogen group-containing compound that contains a nonionic group, the glass transition temperature of the first polyurethane resin can be lowered, and therefore the adhesion between the first layer 3 made of the first polyurethane resin and the polyolefin substrate 2 can be improved.

Furthermore, if the glass transition temperature of the first polyurethane resin is relatively low, if the second layer 4 (described later) is relatively hard (for example, a layered inorganic compound (described later) may be added to the second layer 4 (described later). 1), the stress generated in the second layer 4 (described later) can be alleviated by the first layer 3 (see FIG. 1).

On the other hand, from the viewpoint of gas barrier properties, it is preferable to use an active hydrogen group-containing compound containing an anionic group alone.

The content ratio of the active hydrogen group-containing compound containing a hydrophilic group is, for example, 1 part by mass or more, preferably 5 parts by mass or more, and, for example, 80 parts by mass or less, preferably 50 parts by mass or less, per 100 parts by mass of the total amount of the first polyol component.

When the hydrophilic group contains a polyoxyethylene group, the content of the active hydrogen group-containing compound that contains the hydrophilic group is preferably adjusted appropriately so that the content of oxyethylene in the first polyurethane resin falls within the range described below.

Further, when a carboxyl group is included as a hydrophilic group, the content ratio of the active hydrogen group-containing compound containing a hydrophilic group is preferably adjusted as appropriate so that the acid value in the first polyurethane resin is within the range described below. Ru.

The first polyol component may also contain other polyols (polyols other than the high molecular weight polyols and the active hydrogen group-containing compounds that contain hydrophilic groups) as optional components.

Examples of other polyols include low molecular weight polyols.

The low molecular weight polyol is a compound having two or more hydroxyl groups and a molecular weight of 60 or more and less than 400, preferably 300 or less. Examples of the low molecular weight polyol include the above-mentioned polyhydric alcohols.

Further, examples of the low molecular weight polyol include polyalkylene oxide having a number average molecular weight of less than 400. Examples of such polyalkylene oxide include polyethylene glycol, polypropylene glycol, polyethylene polypropylene glycol (random or block copolymer), and the like.

The low molecular weight polyols can be used alone or in combination of two or more.

As the low molecular weight polyol, preferably, a dihydric alcohol is used, more preferably, polyethylene glycol, and even more preferably, triethylene glycol is used.

When a low molecular weight polyol is blended, the blending ratio is, for example, 20 parts by mass or less, preferably 10 parts by mass or less, and more preferably 5 parts by mass or less, per 100 parts by mass of the total amount of the first polyol component.

To synthesize the first isocyanate-terminated prepolymer, the above components are mixed in an equivalent ratio (isocyanate group/hydroxyl group) of the isocyanate groups of the first isocyanate component to the hydroxyl groups of the first polyol component that exceeds 1, preferably 1.1 to 10, and more preferably 1.1 to 2.0. The above components are then reacted by a known polymerization method such as bulk polymerization or solution polymerization, preferably solution polymerization, which allows easier adjustment of reactivity and viscosity.

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.

In solution polymerization, for example, the above components are blended into an organic solvent under a nitrogen atmosphere and reacted at a reaction temperature of 20 to 80° C. for about 1 to 20 hours. Examples of the organic solvent include acetone, methyl ethyl ketone, ethyl acetate, tetrahydrofuran, and acetonitrile, which are inert toward isocyanate groups and highly hydrophilic.

This polymerization reaction is carried out until the isocyanate group content in the reaction solution becomes 15% by mass or less, preferably 10% by mass or less, more preferably 5% by mass or less.

In addition, in the above polymerization, for example, an amine-based, tin-based, or lead-based reaction catalyst may be added as necessary, and unreacted first polymer may be added from the obtained first isocyanate group-terminated prepolymer. Isocyanates can also be removed by known methods such as distillation or extraction.

For example, when an anionic group is included as a hydrophilic group, it is preferable to add a neutralizing agent to neutralize the hydrophilic group and form a salt of the anionic group.

Neutralizing agents include conventional bases, such as organic bases (e.g., tertiary amines (trialkylamines having 1 to 4 carbon atoms, such as trimethylamine and triethylamine, alkanolamines such as dimethylethanolamine, methyldiethanolamine, triethanolamine and triisopropanolamine, heterocyclic amines such as morpholine, etc.)), inorganic bases (ammonia, alkali metal hydroxides (lithium hydroxide, sodium hydroxide, potassium hydroxide, etc.), alkaline earth metal hydroxides (magnesium hydroxide, calcium hydroxide, etc.), alkali metal carbonates (sodium carbonate, potassium carbonate, etc.)). These bases can be used alone or in combination of two or more.

The neutralizing agent is added in a proportion of 0.4 equivalent or more, preferably 0.6 equivalent or more, and, for example, 1.2 equivalent or less, preferably 1 equivalent or less, per equivalent of anionic group. Add with

The first isocyanate-terminated prepolymer thus obtained is a polyurethane prepolymer having two or more free isocyanate groups at its molecular terminals, and the content of the isocyanate groups (isocyanate group content calculated as solid content excluding solvent) is, for example, 0.3% by mass or more, preferably 0.5% by mass or more, more preferably 1.0% by mass or more, and, for example, 15% by mass or less, preferably 12% by mass or less, more preferably 10% by mass or less, more preferably 5% by mass or less.

The average number of functional groups of the isocyanate groups is, for example, 1.5 or more, preferably 1.9 or more, more preferably 2.0 or more, and is, for example, 3.0 or less, preferably 2.5 or less.

Further, 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 is, for example, 10,000 or less, preferably 5,000 or less. .

When a polyoxyethylene group is included as a hydrophilic group, the content ratio (feeding ratio) of oxyethylene is determined from the viewpoint of improving adhesion and gas barrier properties, and further improving the storage stability of the first dispersion. For example, 1% by mass or more, preferably 5% by mass or more, more preferably 10% by mass or more, even more preferably 12% by mass or more, even more preferably, based on the total amount of the first isocyanate group-terminated prepolymer, 15% by mass or more, for example, 50% by mass or less, preferably 45% by mass or less, more preferably 40% by mass or less, still more preferably 30% by mass or less, particularly preferably 20% by mass or less. .

When the hydrophilic group contains a carboxy group, the acid value of the first isocyanate-terminated prepolymer (based on JIS K 1557-5 (2007)) is, from the viewpoint of improving the storage stability of the first dispersion, for example, 1 mgKOH/g or more, preferably 5 mgKOH/g or more, more preferably 8 mgKOH/g or more, even more preferably 10 mgKOH/g or more, even more preferably 14 mgKOH/g or more, and particularly preferably 15 mgKOH/g or more, and from the viewpoint of improving the adhesion (lamination strength), for example, 70 mgKOH/g or less, preferably 50 mgKOH/g or less, more preferably 45 mgKOH/g or less, even more preferably 40 mgKOH/g or less, even more preferably 35 mgKOH/g or less, even more preferably 30 mgKOH/g or less, even more preferably 24 mgKOH/g or less, and particularly preferably 20 mgKOH/g or less.

Next, in this method, the first isocyanate-terminated prepolymer obtained above is reacted with a first chain extender, for example, in water, to obtain a polyurethane dispersion of the first polyurethane resin.

The first chain extender contains polyamine as an essential component.

Examples of polyamines include aromatic polyamines, araliphatic polyamines, alicyclic polyamines, aliphatic polyamines, amino alcohols, primary amino groups, or alkoxysilyls having a primary amino group and a secondary amino group. compounds, polyoxyethylene group-containing polyamines, and the like.

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

Examples of the araliphatic polyamine include 1,3- or 1,4-xylylene diamine or mixtures thereof.

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.

Examples of aliphatic polyamines include ethylenediamine, propylenediamine, 1,3-propanediamine, 1,4-butanediamine, 1,5-pentanediamine, 1,6-hexamethylenediamine, hydrazine (including hydrates), diethylenetriamine, triethylenetetramine, tetraethylenepentamine, 1,2-diaminoethane, 1,2-diaminopropane, and 1,3-diaminopentane.

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), etc.

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

Examples of polyoxyethylene group-containing polyamines include polyoxyalkylene ether diamines such as polyoxyethylene ether diamine. More specifically, examples include PEG #1000 diamine manufactured by NOF, and Jeffamine ED-2003, EDR-148, and XTJ-512 manufactured by Huntsman.

These polyamines can be used alone or in combination of two or more.

Preferable examples of the polyamine include aliphatic polyamines, amino alcohols, and alkoxysilyl compounds having a primary amino group and a secondary amino group. More preferably, aliphatic polyamines are used alone; Also included is the combined use of alcohol and an alkoxysilyl compound having a primary amino group and a secondary amino group.

In order to react the first isocyanate group-terminated prepolymer and the first chain extender in water, for example, first, by adding the first isocyanate group-terminated prepolymer to water, the first isocyanate group-terminated prepolymer is added to water. After dispersing, a first chain extender is added thereto to chain extend the first isocyanate group-terminated prepolymer with the first chain extender.

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

Then, the first chain extender is dropped into the water in which the first isocyanate-terminated prepolymer is dispersed, while stirring, so that the equivalent ratio (active hydrogen group/isocyanate group) of the active hydrogen groups (amino group and hydroxyl group) of the first chain extender to the isocyanate groups of the first isocyanate-terminated prepolymer is, for example, 0.6 to 1.2, preferably 0.7 to 0.9.

The first chain extender is reacted by dropping the first chain extender, and after the dropwise addition is completed, the reaction is completed at room temperature, for example, with further stirring. The reaction time until the reaction is completed is, for example, 0.1 hour or more and, for example, 10 hours or less.

Note that, contrary to the above, water is added to the first isocyanate group-terminated prepolymer to disperse the first isocyanate group-terminated prepolymer in water, and then the first chain extender is added thereto to form the first isocyanate group-terminated prepolymer. It is also possible to chain extend the isocyanate group-terminated prepolymer using a first chain extender.

Thereby, a first polyurethane resin can be obtained, and a first dispersion in which the first polyurethane resin is dispersed in water can be obtained. Moreover, in this method, the organic solvent and water can be removed as necessary, and furthermore, water can be added to adjust the solid content concentration.

Moreover, the first dispersion can contain various additives as necessary. Examples of additives include silane coupling agents, alkoxysilane compounds, stabilizers (antioxidants, heat stabilizers, ultraviolet absorbers, etc.), plasticizers, antistatic agents, lubricants, antiblocking agents, surfactants, Examples include dispersion stabilizers, colorants (pigments, dyes, etc.), fillers, colloidal silica, inorganic particles, inorganic oxide particles, crystal nucleating agents, and the like.

The additives may be mixed in advance with each of the raw material components, or may be mixed with the first isocyanate-terminated prepolymer or the first polyurethane resin after synthesis, or may be mixed simultaneously with the mixing of each of these components. The mixing ratio of the additives is not particularly limited and may be set appropriately depending on the purpose and application.

The sum of the urethane group concentration and the urea group concentration of the first polyurethane resin is, as a calculated charge value, for example, 5% by mass or more, preferably 8% by mass or more, and for example, 30% by mass or less, preferably 20% by mass or less.

In addition, when the polyester polyol is a reaction product of a polybasic acid containing an aromatic polycarboxylic acid and a polyhydric alcohol, the content ratio of aromatic rings derived from the aromatic polycarboxylic acid (preparation calculation value) is For example, it is 5% by mass or more, preferably 15% by mass or more, more preferably 30% by mass or more, still more preferably 40% by mass or more, and for example 100% by mass, based on the total amount of the first polyurethane resin. It is preferably less than 90% by weight, more preferably less than 80% by weight, even more preferably less than 70% by weight.

When the hydrophilic group contains a polyoxyethylene group, the content ratio of oxyethylene (feed ratio) is, from the viewpoint of improving adhesion and gas barrier properties and further improving the storage stability of the first dispersion, for example, 3% by mass or more, preferably 5% by mass or more, more preferably 10% by mass or more, and even more preferably 13% by mass or more, relative to the total amount of the first polyurethane resin, and for example, 40% by mass or less, preferably 30% by mass or less, more preferably 25% by mass or less, and even more preferably 18% by mass or less.

When a carboxyl group is included as a hydrophilic group, the acid value (according to JIS K 1557-5 (2007)) of the first polyurethane resin is, for example, 5 mgKOH/g or more, preferably 10 mgKOH/g or more, for example, 40 mgKOH /g or less, preferably 20mgKOH/g or less.

Further, the solid content concentration of the first dispersion is, for example, 10% by mass or more, preferably 15% by mass or more, more preferably 20% by mass or more, and, for example, 60% by mass or less, preferably, It is 50% by mass or less, more preferably 40% by mass or less.

The pH of the first dispersion (based on JIS Z 8802 (2011)) is, for example, 5 or more, preferably 6 or more, and, for example, 8 or less, preferably 7.5 or less.

The viscosity of the first dispersion at 25°C (based on JIS K 7117 (1999)) is, for example, 3 mPa·s or more, preferably 5 mPa·s or more, and, for example, 100 mPa·s or less, preferably 50 mPa·s or less.

The average particle size of the first dispersion (measurement method: in accordance with the examples described below) is, for example, 10 nm or more, preferably 20 nm or more, and, for example, 500 nm or less, preferably 300 nm or less.

The first dispersion is used as an anchor coating agent. That is, the first layer 3, which serves as an anchor coating layer, is formed from the first dispersion.

More specifically, to form the first layer 3, for example, the concentration of the first dispersion obtained by the above method is adjusted to prepare an anchor coating agent (AC agent). The obtained anchor coating agent is then applied onto the polyolefin substrate 2 and dried.

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

In addition, a hardener can be added to the anchor coating agent if necessary.

Examples of the curing agent include epoxy curing agents, melamine curing agents, carbodiimide curing agents, aziridine curing agents, oxazoline curing agents, and isocyanate curing agents. Among these, isocyanate curing agents are more specifically water-dispersible isocyanate curing agents (e.g., blocked isocyanates (e.g., tolylene diisocyanate-based blocked isocyanates, hexamethylene diisocyanate-based blocked isocyanates, xylylene diisocyanates). Examples include blocked isocyanates based on hydrogenated xylylene diisocyanate, unblocked polyisocyanates containing hydrophilic groups, etc.

When blending a curing agent, the blending ratio is, for example, 0.1 part by mass or more, preferably 1 part by mass, of the curing agent in terms of solid content per 100 parts by mass of the solid content of the first polyurethane resin. The amount is at least 50 parts by mass, and preferably at most 30 parts by mass.

The method for applying the anchor coating agent is not particularly limited, and examples include known coating methods such as gravure coating, reverse coating, roll coating, bar coating, spray coating, air knife coating, and dipping. can be mentioned.

It may also be applied in-line when preparing the polyolefin substrate 2.

Specifically, when the polyolefin base material 2 is in the form of a film, after uniaxial stretching in the longitudinal direction during film formation, an anchor coating agent is applied and dried by a gravure coating method or the like, and then biaxial stretching is performed. A layer 3 can be provided on the polyolefin substrate 2.

In addition, when the polyolefin substrate 2 is bottle-shaped, an anchor coating agent can be applied to the preform before blow molding by a dipping method or the like, dried, and then the first layer 3 can be provided on the polyolefin substrate 2 by blow molding.

Further, regarding the drying conditions, the drying temperature is, for example, 40°C or higher, preferably 50°C or higher, and, for example, 200°C or lower, preferably 180°C or lower. Further, 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.

This allows a first layer 3 made of a first polyurethane resin to be formed as an anchor coat layer on top of the polyolefin substrate 2.

The thickness of the first layer 3, in terms of the amount of lamination of the first polyurethane resin (after drying), is, for example, 0.05 g/ ^m2 or more, preferably 0.1 g/ ^m2 or more, and more preferably 0.2 g/ ^m2 or more, and for example, 5 g/ ^m2 or less, preferably 3 g/ ^m2 or less, more preferably 1.0 g/ ^m2 or less, and even more preferably 0.6 g/ ^m2 or less.

The second layer 4 is a polyurethane layer made of a second polyurethane resin.

The second polyurethane resin is a reaction product of a second isocyanate group-terminated prepolymer, which is a reaction product of a second isocyanate component and a second polyol component, and a second chain extender containing a polyamine.

Note that, from the viewpoint of manufacturing efficiency, the second layer 4 is preferably formed by applying a polyurethane dispersion (second dispersion) containing a second polyurethane resin to the first layer 3 and drying it. .

To prepare a polyurethane dispersion (second dispersion) containing a second polyurethane resin, the second polyurethane resin is synthesized as an aqueous polyurethane resin, and the resulting aqueous polyurethane resin is dispersed in water.

More specifically, in this method, for example, a second isocyanate component and a second polyol component are reacted to synthesize a second isocyanate group-terminated prepolymer.

The second isocyanate component contains xylylene diisocyanate and/or hydrogenated xylylene diisocyanate as essential components.

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

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

In addition, as hydrogenated xylylene diisocyanate (also known as bis(isocyanatomethyl)cyclohexane) (H ₆ XDI), 1,2-hydrogenated xylylene diisocyanate (o-H ₆ Examples of structural isomers include isocyanate (m-H ₆ XDI) and 1,4-hydrogenated xylylene diisocyanate (p-H ₆ XDI).

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

Xylylene diisocyanate and/or hydrogenated xylylene diisocyanate also include their derivatives.

Examples of derivatives of xylylene diisocyanate and/or hydrogenated xylylene diisocyanate include derivatives similar to the polyisocyanate derivatives described above. More specifically, examples include multimers of xylylene diisocyanate and/or hydrogenated xylylene diisocyanate, allophanate derivatives, polyol derivatives, biuret derivatives, urea derivatives, oxadiazinetrione derivatives, carbodiimide derivatives, uretdione derivatives, and uretonimine derivatives. These derivatives can be used alone or in combination of two or more types.

As the second isocyanate component, a combination of xylylene diisocyanate and hydrogenated xylylene diisocyanate is preferably used.

Adhesion can be improved by using xylylene diisocyanate and hydrogenated xylylene diisocyanate together.

When xylylene diisocyanate and hydrogenated xylylene diisocyanate are used in combination, the proportion of xylylene diisocyanate relative to 100 parts by mass of the total of xylylene diisocyanate and hydrogenated 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. The proportion of hydrogenated xylylene diisocyanate 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.

The second isocyanate component may also contain, as an optional component, a polyisocyanate other than xylylene diisocyanate and hydrogenated xylylene diisocyanate (hereinafter referred to as other polyisocyanates).

Examples of other polyisocyanates include the aromatic polyisocyanates described above, the aromatic aliphatic polyisocyanates described above (excluding xylylene diisocyanate), the aliphatic polyisocyanates described above, and the alicyclic polyisocyanates described above (excluding hydrogenated xylylene diisocyanate). In addition, the other polyisocyanates include the same derivatives as those described above.

These other polyisocyanates can be used alone or in combination of two or more types.

When the second isocyanate component contains another polyisocyanate, the content is, for example, 30 parts by mass or less, preferably 20 parts by mass or less, per 100 parts by mass of the total amount of the second isocyanate component.

The second isocyanate component preferably does not contain any other polyisocyanate and consists of xylylene diisocyanate and/or hydrogenated xylylene diisocyanate.

The second polyol component contains a low molecular weight polyol as an essential component.

The low molecular weight polyol contains a diol (dihydric alcohol) having 2 to 6 carbon atoms as an essential component.

The diol having 2 to 6 carbon atoms is an organic compound having 2 to 6 carbon atoms and having two hydroxyl groups, and specifically includes, for example, ethylene glycol, propylene glycol, 1,3-propanediol, 1,4- Butylene glycol, 1,3-butylene glycol, 1,2-butylene glycol, 1,5-pentanediol, 1,6-hexanediol, neopentyl glycol, 3-methyl-1,5-pentanediol, 1,3- or alkanediols having 2 to 6 carbon atoms such as 1,4-cyclohexanediol, ether diols having 2 to 6 carbon atoms such as diethylene glycol, triethylene glycol, dipropylene glycol, for example 1,4-dihydroxy-2- Examples include alkenediols having 2 to 6 carbon atoms such as butene.

These diols having 2 to 6 carbon atoms can be used alone or in combination of two or more.

As the diol having 2 to 6 carbon atoms, from the viewpoint of gas barrier properties, preferably, an alkanediol having 2 to 6 carbon atoms, more preferably, ethylene glycol, is used.

The content of the diol having 2 to 6 carbon atoms is, for example, 20 parts by mass or more, preferably 40 parts by mass or more, more preferably 50 parts by mass or more, and for example, 90 parts by mass or less, preferably 80 parts by mass or less, relative to 100 parts by mass of the total amount of the second polyol component.

Furthermore, the low molecular weight polyol may further contain, as an optional component, a low molecular weight polyol other than the above-mentioned diols having 2 to 6 carbon atoms (hereinafter referred to as other low molecular weight polyols).

Other low molecular weight polyols include, for example, alkane-1,2-diol having 7 to 20 carbon atoms, 2,6-dimethyl-1-octene-3,8-diol, 1,3- or 1,4-cyclohexane Dihydric alcohols having 7 or more carbon atoms such as dimethanol and mixtures thereof, hydrogenated bisphenol A, bisphenol A, trihydric alcohols such as glycerin, trimethylolpropane, e.g. tetramethylolmethane (pentaerythritol), diglycerin Tetrahydric alcohols such as, for example, pentahydric alcohols such as xylitol, hexahydric alcohols such as sorbitol, mannitol, allitol, iditol, dulcitol, altritol, inositol, dipentaerythritol, heptahydric alcohols such as perseitol, Examples include octahydric alcohols such as sucrose.

Other examples of low molecular weight polyols include polyalkylene oxides having a number average molecular weight of less than 400. Examples of such polyalkylene oxides include polyethylene glycol, polypropylene glycol, and polyethylene polypropylene glycol (random or block copolymers).

Other low molecular weight polyols can be used alone or in combination of two or more.

Other low molecular weight polyols are preferably trihydric alcohols, more preferably glycerin and trimethylolpropane.

When other low molecular weight polyols (excluding the above-mentioned diols having 2 to 6 carbon atoms) are blended, the blending ratio is, 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 second polyol component.

The low molecular weight polyol preferably contains a diol having 2 to 6 carbon atoms and another low molecular weight polyol, and more preferably contains a diol having 2 to 6 carbon atoms and a trihydric alcohol. By containing a diol having 2 to 6 carbon atoms and a trihydric alcohol, the first polyurethane resin can be made to have a high molecular weight, and an improvement in coating film strength can be expected.

When containing a diol having 2 to 6 carbon atoms and a trihydric alcohol, the proportion thereof is such that the trihydric alcohol is, for example, based on 100 parts by mass of the diol having 2 to 6 carbon atoms and the trihydric alcohol. The amount is 0.1 part by mass or more, preferably 1 part by mass or more, and for example, 20 parts by mass or less, preferably 10 parts by mass or less.

Moreover, the second polyol component contains an active hydrogen group-containing compound containing a hydrophilic group as an essential component.

Examples of active hydrogen group-containing compounds that contain hydrophilic groups include the active hydrogen group-containing compounds that contain hydrophilic groups described above as the first polyol component, and more specifically, examples of active hydrogen group-containing compounds that contain nonionic groups described above, and active hydrogen group-containing compounds that contain ionic groups described above, etc.

These active hydrogen group-containing compounds containing hydrophilic groups can be used alone or in combination of two or more.

From the viewpoint of gas barrier properties, the active hydrogen group-containing compound containing a hydrophilic group preferably includes an active hydrogen group-containing compound containing an ionic group, and more preferably an active hydrogen group-containing compound containing an anionic group. Examples include group-containing compounds, more preferably carboxy group-containing polyols, particularly preferably polyhydroxyalkanoic acids.

The content ratio of the active hydrogen group-containing compound containing a hydrophilic group is, for example, 10 parts by mass or more, preferably 20 parts by mass or more, more preferably 25 parts by mass, based on 100 parts by mass of the total amount of the second polyol component. For example, it is 50 parts by mass or less, preferably 40 parts by mass or less.

The second polyol component may also contain the above-mentioned high molecular weight polyol as an optional component, provided that the excellent effects of the present invention are not impaired.

When a high molecular weight polyol is blended, the blending ratio is, for example, 20 parts by mass or less, preferably 10 parts by mass or less, and more preferably 5 parts by mass or less of high molecular weight polyol per 100 parts by mass of the total amount of the second polyol component.

The second polyol component preferably does not contain a high molecular weight polyol, and is composed of the above-mentioned low molecular weight polyol and the above-mentioned active hydrogen group-containing compound that contains a hydrophilic group.

In order to synthesize the second isocyanate group-terminated prepolymer, each of the above components is preferably added in a ratio exceeding 1 in the equivalent ratio of the second isocyanate group to the hydroxyl group of the second polyol component (isocyanate group/active hydrogen group). is blended in a ratio of 1.1 to 10, more preferably 1.1 to 2.0. Then, the above-mentioned components are reacted by a known polymerization method such as bulk polymerization or solution polymerization, preferably by solution polymerization, which allows easier adjustment of reactivity and viscosity.

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.

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

This polymerization reaction is carried out until the isocyanate group content in the reaction solution is 15% by mass or less, preferably 10% by mass or less.

In addition, in the above polymerization, the above catalyst may be added as necessary, and unreacted second polyisocyanate can be removed from the obtained second isocyanate group-terminated prepolymer by a known method such as distillation or extraction. It can also be removed by the following method.

For example, when an anionic group is included as a hydrophilic group, preferably, the above-mentioned neutralizing agent is added in the above-mentioned ratio to neutralize and form a salt of the anionic group.

The second isocyanate-terminated prepolymer thus obtained is a polyurethane prepolymer having two or more free isocyanate groups at its molecular terminals, and the content of the isocyanate groups (isocyanate group content calculated as solid content excluding solvent) is, for example, 0.3% by mass or more, preferably 0.5% by mass or more, more preferably 1.0% by mass or more, and, for example, 15% by mass or less, preferably 12% by mass or less, more preferably 10% by mass or less.

Further, the average number of functional groups of the isocyanate group is, for example, 1.5 or more, preferably 1.9 or more, more preferably 2.0 or more, and, for example, 3.0 or less, preferably 2.5. It is as follows.

If the average number of functional groups of the isocyanate groups is within the above range, a stable dispersion of the second polyurethane resin can be obtained, and adhesion to the substrate, gas barrier properties, etc. can be ensured.

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.

Next, in this method, the second isocyanate group-terminated prepolymer obtained above and a second chain extender are reacted, for example, in water to obtain a polyurethane dispersion of the second polyurethane resin.

The second chain extender contains the above polyamine as an essential component.

Specific examples of polyamines include the above-mentioned aromatic polyamines, the above-mentioned araliphatic polyamines, the above-mentioned alicyclic polyamines, the above-mentioned aliphatic polyamines, the above-mentioned amino alcohols, the above-mentioned alkoxysilyl compounds, and the above-mentioned polyoxyethylene group-containing polyamines. These polyamines can be used alone or in combination of two or more kinds. A preferred example of the polyamine is an amino alcohol.

The method of reacting the second isocyanate group-terminated prepolymer and the second chain extender in water is the same as described above. For example, first, the second isocyanate group-terminated prepolymer is added to water to disperse the second isocyanate group-terminated prepolymer in water, and then the second chain extender is added thereto at the above ratio to disperse the second isocyanate group-terminated prepolymer into water. The isocyanate group-terminated prepolymer is chain-extended using a second chain extender. Note that, on the contrary, water is added to the second isocyanate group-terminated prepolymer to disperse the second isocyanate group-terminated prepolymer in water, and then a second chain extender is added thereto to form the second isocyanate group-terminated prepolymer. It is also possible to chain extend the isocyanate group-terminated prepolymer using a second chain extender.

Thereby, a second polyurethane resin can be obtained, and a second dispersion in which the second polyurethane resin is dispersed in water can be obtained. Moreover, in this method, the organic solvent and water can be removed as necessary, and furthermore, water can be added to adjust the solid content concentration.

Moreover, the second dispersion can contain various additives as necessary. Examples of additives include silane coupling agents, alkoxysilane compounds, stabilizers (antioxidants, heat stabilizers, ultraviolet absorbers, etc.), plasticizers, antistatic agents, lubricants, antiblocking agents, surfactants, Examples include dispersion stabilizers, colorants (pigments, dyes, etc.), fillers, colloidal silica, inorganic particles, inorganic oxide particles, crystal nucleating agents, and the like. Additionally, examples of additives include thermoplastic resins having gas barrier properties (for example, polyvinyl alcohol, ethylene-vinyl alcohol copolymers, polyvinylidene chloride or vinylidene chloride copolymers, starch, polysaccharides such as cellulose, etc.). .

The additives may be added in advance to each of the raw material components, or may be added to the second isocyanate-terminated prepolymer or the second polyurethane resin after synthesis, or may be added simultaneously when these components are mixed. The mixing ratio of the additives is not particularly limited and may be set appropriately depending on the purpose and application.

The total value of the urethane group concentration and the urea group concentration of the second polyurethane resin is, for example, 20% by mass or more, preferably 25% by mass or more, and is, for example, 50% by mass or less, preferably is 45% by mass or less.

The solids concentration of the second dispersion is, for example, 10% by mass or more, preferably 15% by mass or more, more preferably 20% by mass or more, and, for example, 60% by mass or less, preferably 50% by mass or less, more preferably 45% by mass or less.

Further, the pH of the second dispersion is, for example, 5 or more, preferably 6 or more, more preferably 7 or more, still more preferably 8 or more, and, for example, 11 or less, preferably 10 or less. be.

The viscosity of the second dispersion at 25° C. is, for example, 3 mPa·s or more, preferably 5 mPa·s or more, and is, for example, 2000 mPa·s or less, preferably 1000 mPa·s or less.

The average particle diameter of the second dispersion is, for example, 10 nm or more, preferably 20 nm or more, and is, for example, 500 nm or less, preferably 300 nm or less, more preferably 200 nm or less, and even more preferably 100 nm. It is as follows.

In addition, in the second layer 4, the second polyurethane resin may also contain a layered inorganic compound.

Examples of the layered inorganic compound include swellable layered inorganic compounds and non-swellable layered inorganic compounds. From the viewpoint of gas barrier properties, swellable layered inorganic compounds are preferred.

Swellable layered inorganic compounds are clay minerals that consist of extremely thin unit crystals and have the property of coordinating or absorbing and swelling with a solvent between the unit crystal layers.

Specific examples of swellable layered inorganic compounds 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.

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

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.

In order to form the second layer 4, a layered inorganic compound is preferably dispersed in the second dispersion obtained above to prepare a barrier coating agent (mixture). Then, the obtained barrier coating agent is applied onto the first layer 3 and dried.

The method of mixing the second dispersion and the layered inorganic compound is not particularly limited, but for example, the second dispersion is added to a dispersion of the layered inorganic compound dispersed in water.

Since there is a risk of secondary aggregation of the layered inorganic compound in the mixture (barrier coating agent), when preparing a dispersion liquid in which the layered inorganic compound is dispersed in water, it is preferable to disperse the layered inorganic compound first, and then to 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, etc.

The blending ratio of the second polyurethane resin and the layered inorganic compound is such that the amount of the layered inorganic compound is 0.1 part by mass or more, preferably 1 part by mass, based on 100 parts by mass of the total mass of the second polyurethane resin and the layered inorganic compound. For example, it is 50 parts by mass or less, preferably 30 parts by mass or less, more preferably 10 parts by mass or less.

When the blending ratio of the second polyurethane resin and the layered inorganic compound is within the above range, gas barrier properties can be maintained and adhesion can be improved.

The total concentration of the second polyurethane resin and the layered inorganic compound in the resulting mixture (barrier coating agent) is, for example, 0.1% by mass or more, preferably 0.5% by mass or more, and, for example, 15% by mass or more. % or less, preferably 12% by mass or less.

Moreover, the above-mentioned curing agent can also be blended into the barrier coating agent, if necessary. Preferably, the curing agent is a water-dispersible isocyanate curing agent.

When the above curing agent is blended, the blending ratio is, for example, 0.1 part by mass or more in terms of solid content, with respect to 100 parts by mass of the total solid content of the second polyurethane resin. Preferably, it is 1 part by mass or more, and for example, 50 parts by mass or less, preferably 30 parts by mass or less.

Further, the method for applying the barrier coating agent is not particularly limited, and the above-mentioned known coating methods may be used.

The drying conditions are as follows: drying temperature is, for example, 40°C or higher, preferably 50°C or higher, and, for example, 200°C or lower, preferably 180°C or lower; and drying time is, for example, 0.1 minutes or higher, preferably 0.2 minutes or higher, and, for example, 10 minutes or lower, preferably 5 minutes or lower.

Thereby, the second layer 4 made of the second polyurethane resin (including a layered inorganic compound if necessary) can be formed on the first layer 3.

The thickness of the second layer 4, expressed as the amount of lamination of the second polyurethane resin (containing a layered inorganic compound as necessary) (after drying), is, for example, 0.1 g/ ^m2 or more, preferably 0.2 g/ ^m2 or more, and more preferably 0.6 g/ ^m2 or more, and for example, 10 g/ ^m2 or less, preferably 7 g/ ^m2 or less, and more preferably 3 g/ ^m2 or less.

Then, as described above, by forming the first layer 3 on the polyolefin base material 2 and forming the second layer 4 on the first layer 3, the polyurethane laminate 1 can be obtained.

The thickness of the polyurethane laminate 1 is, for example, 5 μm or more, preferably 10 μm or more, and is, for example, 1 mm or less, preferably 0.5 mm or less.

Further, in the polyurethane laminate 1, the total thickness of the first layer 3 and the second layer 4 is, for example, 0.1 g/m ² or more, preferably 0.2 g/m ² or more, as the amount of lamination after drying. , more preferably 0.8 g/m ² or more, and, for example, 20 g/m ² or less, preferably 15 g/m ² or less, more preferably 10 g/m ² or less, and even more preferably 5 g/m 2 or less. ^m2 or less.

The thickness ratio of the first layer 3 to the second layer 4 is, based on height (μm), for example, 1% or more, preferably 2% or more, and for example, 50% or less, preferably 20% or less, of the total thickness of the first layer 3 and the second layer 4. The thickness ratio of the second layer 4 is, for example, 50% or more, preferably 80% or more, and for example, 99% or less, preferably 98% or less.

The thickness of the second layer 4 is thicker than that of the first layer 3, and is, for example, 0.8 times or more, preferably 1.0 times or more, more preferably 1.5 times or more, and usually 5 times or less, the thickness of the first layer 3.

The mass ratio of the first layer 3 and the second layer 4 is, relative to the total mass of 100 parts by mass, for example, 0.01 parts by mass or more, preferably 0.1 parts by mass or more, more preferably 0.2 parts by mass or more, and even more preferably 10 parts by mass or more of the first layer 3, and for example, 60 parts by mass or less, preferably 50 parts by mass or less, more preferably 30 parts by mass or less, and even more preferably 20 parts by mass or less of the second layer 4. The mass of the second layer 4 is, for example, 40 parts by mass or more, preferably 50 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, 99.99 parts by mass or less, preferably 99.9 parts by mass or less, more preferably 99.8 parts by mass or less, and even more preferably 90 parts by mass or less.

If the mass ratio of the first layer 3 and the second layer 4 is within the above range, a polyurethane laminate 1 with excellent adhesiveness and gas barrier properties can be obtained.

In the polyurethane laminate 1, the mass ratio of the layered inorganic compound 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, per 100 parts by mass of the total of the mass of the first layer 3 and the mass of the second layer 4, and is, for example, 90 parts by mass or less, preferably 70 parts by mass or less, and more preferably 50 parts by mass or less.

If the mass ratio of the layered inorganic compound is within the above range, a polyurethane laminate 1 with excellent adhesion and gas barrier properties can be obtained.

Further, if necessary, the obtained polyurethane laminate 1 may be cured, for example, at 30 to 50° C. for about 2 to 5 days.

The polyurethane laminate 1 obtained in this manner has excellent gas barrier properties and excellent adhesion to polyolefin substrates.

Therefore, the polyurethane laminate 1 is suitably used in the field of gas barrier films, specifically, food packaging films, optical films, industrial films, and the like. Further, the polyurethane laminate 1 is suitably used, for example, in the printing field. That is, a barrier coating agent containing the second polyurethane resin is impregnated with a coloring agent such as a pigment to prepare a printing ink, and this is applied to a plastic film, paper, various containers, etc. to create a printing film or printed material. It can also be suitably used as

In the above embodiment, the first layer 3 and the second layer 4 are laminated over the entire surface of one side of the polyolefin substrate 2 in the thickness direction, but the present invention is not limited to this. For example, although not shown, the first layer 3 and the second layer 4 can be laminated over both sides of the polyolefin substrate 2 in the thickness direction, or even partially. The first layer 3 and/or the second layer 4 can be laminated on the first layer 3 and the second layer 4. The first layer 3 may be formed by in-line coating during the production of each thermoplastic film.

Next, the present invention will be explained based on Examples and Comparative Examples, but the present invention is not limited to the following Examples. Note that "parts" and "%" are based on mass unless otherwise specified. In addition, specific numerical values such as blending ratios (content ratios), physical property values, parameters, etc. used in the following description are the corresponding blending ratios (content ratios) described in the above "Detailed Description" Substitute with the upper limit value (value defined as "less than" or "less than") or lower limit value (value defined as "more than" or "exceeding") of the corresponding description, such as content percentage), physical property value, parameter, etc. be able to.

<Synthesis Examples 1 to 9: Synthesis of polyester polyol>
In a reaction vessel equipped with a thermometer, a nitrogen gas inlet tube, and a stirrer, a polybasic acid and a polyhydric alcohol were charged with nitrogen gas according to the recipe shown in Table 1. Furthermore, stannous octoate (Stannoct, Mitsubishi Chemical Corporation) was charged as a catalyst according to the recipe shown in Table 1.

Then, the above components were subjected to a polycondensation reaction at the reaction temperature and reaction time shown in Table 1 until the acid value became 1 or less. Thereby, a polyester polyol was obtained.

Number average molecular weight of polyester polyol (number average molecular weight measured by GPC using standard polystyrene as a calibration curve), hydroxyl value (based on method A or method B of JIS K 1557-1 (2007)), and acid value (JIS K 1557-1) 5 (2007)) are shown in Table 1.

Further, Table 1 shows the proportion of aromatic polycarboxylic acid in the polybasic acid used in the synthesis of polyester polyol.

<Production Examples 1 to 41: First Dispersion>
First dispersions were prepared according to the formulations shown in Tables 2 to 8.

That is, the first isocyanate component, the first polyol component, and the solvent (acetonitrile) are mixed according to the recipe shown in the table, and the isocyanate group content of the reaction solution is about 2.4% by mass at 65 to 70°C in a nitrogen atmosphere. The reaction was allowed to occur until . As a result, a first isocyanate group-terminated prepolymer was obtained.

In this reaction, the equivalent ratio (isocyanate group/hydroxyl group) of the isocyanate group of the first isocyanate component to the hydroxyl group of the first polyol component was as described in the table.

Then, the solution of the first isocyanate-terminated prepolymer was cooled to 40°C. In addition, for those using 2,2-dimethylolpropionic acid as the active hydrogen group-containing compound containing a hydrophilic group, triethylamine was added to neutralize it according to the formula shown in the table.

Thereafter, the first isocyanate group-terminated prepolymer was dispersed in ion-exchanged water according to the recipe shown in the table. An aqueous solution in which the first chain extender was dissolved in ion-exchanged water was added thereto to cause a chain extension reaction.

In this reaction, the equivalent ratio (active hydrogen group/isocyanate group) of the active hydrogen group (amino group and hydroxyl group) of the first chain extender to the isocyanate group of the first isocyanate group-terminated prepolymer is 0.8. there were.

After the chain extension reaction, the mixture was aged for 1 hour, and then methyl ethyl ketone and ion-exchanged water were distilled off using an evaporator, and the product was prepared with ion-exchanged water so that the solid content was 30% by mass. As a result, dispersions (PUD 1 to 32) of the first polyurethane resin were obtained.

In addition, the pH of PUD (based on JIS Z 8802 (2011)), the viscosity at 25°C (based on JIS K 7117 (1999)), the average particle diameter (measured with Coulter Counter N5 (manufactured by Beckman)), , the total value of the urethane group concentration and the urea group concentration (preparation calculation value) is shown in Tables 2 to 8.

The oxyethylene group concentration of the first polyurethane resin was measured using the following method and is shown in the table.

A certain amount of tetrachloroethane dissolved in deuterated chloroform was added as an internal standard substance to 0.5 g of the first polyurethane resin, and further deuterated chloroform was added to make the total volume 5 mL. The oxyethylene group concentration was determined by ¹ H-NMR (JNM-AL400 manufactured by JEOL) measurement of this solution.

<Manufacture example 42: Second dispersion>
As the second isocyanate component, 169.9 parts by mass of 1,3-xylylene diisocyanate (m-XDI) (trade name: Takenate 500, manufactured by Mitsui Chemicals) and 1,3-bis(isocyanatomethyl)cyclohexane (m-XDI) were used as the second isocyanate component. -H ₆ XDI) (trade name: Takenate 600, manufactured by Mitsui Chemicals) 29.2 parts by mass was prepared.

Further, as the second polyol component, 35.9 parts by mass of ethylene glycol, 3.4 parts by mass of trimethylolpropane, and 18.2 parts by mass of dimethylolpropionic acid were prepared.

Then, the second isocyanate component, the second polyol component, and 115.8 parts by mass of methyl ethyl ketone as a solvent are mixed, and the isocyanate group content of the reaction solution becomes 6.79% by mass or less at 65 to 70°C in a nitrogen atmosphere. I reacted until. In this way, a second isocyanate group-terminated prepolymer was synthesized.

In this reaction, the equivalent ratio of the isocyanate groups of the second isocyanate component to the hydroxyl groups of the second polyol component (isocyanate groups/hydroxyl groups) was 1.4.

Then, the solution of the second isocyanate-terminated prepolymer was cooled to 40°C and neutralized with 13.6 parts by mass of triethylamine.

Then, the second isocyanate-terminated prepolymer was dispersed in ion-exchanged water. An aqueous solution of 29.8 parts by mass of 2-((2-aminoethyl)amino)ethanol as a second chain extender dissolved in 59.6 parts by mass of ion-exchanged water was added thereto, and a chain extension reaction was carried out.

In this reaction, the equivalent ratio (isocyanate group/active hydrogen group) of the isocyanate groups of the second isocyanate-terminated prepolymer to the active hydrogen groups (amino groups and hydroxyl groups) of the second chain extender was 0.95.

After the chain extension reaction, the mixture was allowed to mature for 1 hour, after which the methyl ethyl ketone and ion-exchanged water were removed using an evaporator, and the mixture was adjusted with ion-exchanged water so that the solid content was 30% by mass. This resulted in a dispersion of the second polyurethane resin (second PUD).

The pH of the second PUD (based on JIS Z 8802 (2011)) is 8.5, the viscosity at 25°C (based on JIS K 7117 (1999)) is 15 mPa・s, and the average particle diameter (based on Coulter Measured with Counter N5 (manufactured by Beckman)) was 80 nm. Further, the total value of the urethane group concentration and the urea group concentration (preparation calculation value) was 40.7% by mass.

<Preparation Example 1: Anchor Coating Agent 1 (AC-1)>
According to Tables 9 to 11, 3.83 parts by mass of PUD and 16.17 parts by mass of ion-exchanged water were mixed and stirred at room temperature for 20 minutes to obtain an anchor coating agent (AC-1) having a solids concentration of 6.7% by mass.

<Preparation Example 2: Anchor Coating Agent 2 (AC-2)>
According to Tables 9 to 11, 6.70 parts by mass of PUD and 13.30 parts by mass of ion-exchanged water were mixed and stirred at room temperature for 20 minutes to obtain an anchor coating agent (AC-2) having a solids concentration of 6.7% by mass.

<Preparation example 3: Barrier coating agent 1 (BC-1)>
4.00 parts by mass of synthetic mica (trade name: MEB-3, manufactured by Co-op Chemical, solid content concentration 8% by mass) was mixed with 12.16 parts by mass of ion-exchanged water at room temperature for 20 minutes with stirring to form a dispersion. I got it.

Next, 3.66 parts by mass of the second PUD was added to the obtained dispersion according to Tables 9 to 11, and mixed for 30 minutes at room temperature.

Thereafter, 0.18 parts by mass of Takenate WD-725 (water-dispersible isocyanate curing agent, manufactured by Mitsui Chemicals, solid content concentration 100% by mass) was added as a hardening agent, and the solid content concentration was increased by mixing for 20 minutes. A barrier coating agent (BC-1) containing 8.0% by mass was obtained.

In addition, the content rate of the layered inorganic compound in the solid content of the barrier coating agent was 20% by mass.

<Preparation example 3: Barrier coating agent 2 (BC-2)>
13.84 parts by mass of ion-exchanged water and 1.42 parts by mass of synthetic mica (trade name: NTS-5, manufactured by Topy Industries, solid content concentration 6% by mass) were mixed at room temperature for 20 minutes with stirring to form a dispersion. I got it.

Next, 4.59 parts by mass of the second PUD was added to the resulting dispersion according to Tables 9 to 11, and mixed at room temperature for 30 minutes.

Thereafter, 0.17 parts by mass of Takenate WD-725 (water-dispersible isocyanate curing agent, manufactured by Mitsui Chemicals, solid content concentration 100% by mass) was added as a hardening agent, and the solid content concentration was increased by mixing for 20 minutes. A barrier coating agent (BC-2) containing 8.0% by mass was obtained.

In addition, the content rate of the layered inorganic compound in the solid content of the barrier coating agent was 5.3% by mass.

<Examples 1 to 39 and Comparative Examples 1 to 5: Polyurethane laminate>
According to Tables 9 to 12, an anchor coating agent was applied to a polyolefin base material (polypropylene film, biaxially oriented polypropylene film (OPP), trade name: Pylene Film-OT P2161, manufactured by Toyobo Co., Ltd., thickness 20 μm) using a bar coater. After drying at 90°C for 1 minute and 30 seconds, it was cured at 50°C for 2 days. As a result, a first layer (anchor coat layer) having a thickness of 0.5 g/m ² was obtained.

Next, a barrier coating agent was applied to the first layer (anchor coating layer) of the film according to Tables 9 to 12 using a bar coater, and the film was dried at 90° C. for 1 minute and 30 seconds. This resulted in a second layer (barrier coating layer) having a thickness of 1.0 g/ ^m2 .

Thereby, a polyurethane laminate was obtained.

<Evaluation>
Regarding the polyurethane laminate, oxygen permeability (gas barrier property), laminate strength (adhesion), and AC agent stability were measured by the following methods. The results are also shown in the table.

(1) Oxygen Permeability Measurement Using an oxygen permeability measuring device (OX-TRAN2/20, manufactured by MOCON), the oxygen permeability per m ² , day, and atmospheric pressure at 20° C. and 80% relative humidity (80% RH) of each polyurethane laminate was measured.

(2) Lamination strength Each polyurethane laminate was coated with dry laminating adhesives (Takenate A-626 (isocyanate adhesive, manufactured by Mitsui Chemicals) and Takenate A-65 (isocyanate adhesive, manufactured by Mitsui Chemicals). A-626/Takenate A-65 in a ratio of 10/1) was applied to a dry thickness of 3.0 g/ ^m2 , and a polypropylene film (unstretched polypropylene film for retorts, Product name: RXC-22, manufactured by Mitsui Chemicals Tohcello Co., Ltd. (thickness 60 μm)) were laminated and cured at 40°C for 3 days. It was measured by a peel test.

(3) Stability of AC agent After storing the anchor coating agent (AC agent) at room temperature for 6 months, the presence or absence of sediment was observed.

○: No sediment was observed.

△: A small amount of sediment was observed.

×: A large amount of sediment was observed.

The details of the abbreviations in the table are given below.

IPDI: Isophorone diisocyanate H ₁₂ MDI: 4,4'-methylenebis(cyclohexyl isocyanate)
HDI: Hexamethylene diisocyanate H ₆ XDI: 1,3-bis(isocyanatomethyl)cyclohexane XDI: 1,3-xylylene diisocyanate PES: Polyester polyol (polyester polyol obtained in each synthesis example)
Plaxel 200: Trade name, polycaprolactone polyol (abbreviated as PCL), number average molecular weight 2000, manufactured by Daicel Chemical Co., Ltd. PTG2000NS: Trade name, polytetramethylene ether glycol (abbreviated as PTG), number average molecular weight 2000, manufactured by Hodogaya Chemical Co., Ltd. UH200: Product name, polycarbonate diol (PC), ETERNACOLL UH-200, manufactured by Ube Industries TEG: triethylene glycol DHD1000S: polyoxyethylene side chain-containing diol, manufactured by Mitsui Chemicals, molecular weight 1000, oxyethylene content 76.0% by mass
AN: Acetonitrile KBM603: Product name, N-2-(aminoethyl)-3-aminopropyltrimethoxysilane, manufactured by Shin-Etsu Chemical Co., Ltd. AEA: 2-((2-aminoethyl)amino)ethanol EDA: Ethylenediamine Broken material: Material Destruction (base material damaged during peeling)

1 Polyurethane laminate 2 Base material 3 First layer 4 Second layer

Claims (7)

a polyolefin base material,
a first layer laminated on the polyolefin base material and made of a first polyurethane resin;
a second layer laminated on the first layer and made of a second polyurethane resin;
The first polyurethane resin is a reaction product of a first isocyanate group-terminated prepolymer, which is a reaction product of a first isocyanate component and a first polyol component, and a first chain extender containing a polyamine,
The first polyol component contains a polyester polyol having a number average molecular weight of 500 or more and an active hydrogen group-containing compound containing a hydrophilic group,
The second polyurethane resin is a reaction product of a second isocyanate group-terminated prepolymer, which is a reaction product of a second isocyanate component and a second polyol component, and a second chain extender containing a polyamine,
The second isocyanate component contains xylylene diisocyanate and/or hydrogenated xylylene diisocyanate,
A polyurethane laminate, wherein the second polyol component contains a diol having 2 to 6 carbon atoms and an active hydrogen group-containing compound containing a hydrophilic group. In the first polyol component,
2. The polyurethane laminate according to claim 1, wherein the active hydrogen group-containing compound containing a hydrophilic group is an active hydrogen group-containing compound containing a nonionic group. the nonionic group is a polyoxyethylene group,
The polyurethane laminate according to claim 2, wherein the content of the oxyethylene is 5% by mass or more and 40% by mass or less based on the total amount of the first polyurethane resin. In the first polyol component,
2. The polyurethane laminate according to claim 1, wherein the active hydrogen group-containing compound containing a hydrophilic group is an active hydrogen group-containing compound containing an anionic group. In the first polyol component,
The polyester polyol having a number average molecular weight of 500 or more is a reaction product of a polybasic acid containing an aromatic polycarboxylic acid and a polyhydric alcohol,
The polyurethane laminate according to any one of claims 1 to 4, wherein the content of the aromatic polycarboxylic acid is 15% by mass or more with respect to the total amount of the polybasic acid. The polyurethane laminate according to any one of claims 1 to 5, wherein the first isocyanate component contains an alicyclic polyisocyanate. The polyurethane laminate according to any one of claims 1 to 6, wherein the first layer is an anchor coat layer.

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