JP6856175B2 - Two-component adhesive, polyisocyanate composition for two-component adhesive, laminate, packaging material - Google Patents

Description

The present invention relates to a two-component adhesive, a polyisocyanate composition for a two-component adhesive, a laminate, and a packaging material.

Packaging materials for foods and beverages have not only functions such as strength, resistance to cracking, retort resistance, and heat resistance to protect the contents from various distribution, storage such as refrigeration, and treatment such as heat sterilization. A wide variety of functions such as excellent transparency are required so that the contents can be confirmed.
On the other hand, when the bag is sealed by heat sealing, a non-stretched polyolefin film having excellent heat processability is indispensable, but the non-stretched polyolefin film has many functions lacking as a packaging material.

For this reason, a composite flexible film in which different types of polymer materials are combined is widely used as the packaging material. In general, a composite flexible film is composed of a thermoplastic film layer or the like which is an outer layer having various functions such as product protection and a thermoplastic film layer which is a sealant layer, and these are bonded together with a thermoplastic for the outer layer. , A method in which a three-layer melt-extruded adhesive and a thermoplastic for a sealant layer are formed to form an unstretched laminated sheet and then stretched (see, for example, Patent Document 1), or an adhesive is applied to a laminate film layer to form a sealant layer. A dry laminating method (see, for example, Patent Document 2) for producing a multilayer film by adhering is known.

In recent years, there has been a demand for higher functionality for multilayer films, and oxygen barrier properties that prevent the intrusion of oxygen from the outside in order to suppress oxidation, carbon dioxide barrier properties, and barrier properties for various aroma components are also required. .. In addition, as one of the methods to extend the expiration date and expiration date of food, in order to prevent the growth of microorganisms and molds that cause food deterioration and putrefaction, inert gas, ethyl alcohol evaporative material and ethyl alcohol It is widely practiced to enclose steam, together with food, in the packaging. In the case of such packaging, in order to maintain the state of food, a barrier function for preventing leakage of inert gas or ethyl alcohol is also required. As a method of imparting a barrier function to a multilayer film, a barrier function is imparted by coating various films (polyester resin such as polyethylene terephthalate (hereinafter abbreviated as PET), polyamide resin, stretched polyolefin resin) used on the outer layer side. A method of imparting a barrier function to an adhesive used at the time of laminating, a method of using a film on which silica, alumina, aluminum or the like is vapor-deposited, and the like are known.

When an alcohol barrier function is imparted to the outer layer film by coating, vinylidene chloride, which has high oxygen barrier properties and water vapor barrier properties (that is, easily hinders mass transfer), has been widely used as the barrier coating material, but it is discarded. In addition to problems such as the generation of dioxins during firing, there is also the problem of yellowing when exposed to light. Further, the polyvinyl alcohol resin and the ethylene-polyvinyl alcohol copolymer having an oxygen barrier function have a problem that the barrier property is further deteriorated under high humidity where the resin swells.

The method of imparting a gas barrier function to the adhesive used at the time of laminating has an advantage that a multilayer film for a gas barrier can be produced without using a film having a special gas barrier function due to the steps and configurations essential for producing the laminated film. have. On the other hand, the flexible molecular structure essential for adhesives generally has high gas permeability. Therefore, the adhesive ability and the gas barrier function are often in a trade-off relationship, and this elimination increases the technical difficulty.

Further, when the laminated film is applied to a food packaging material, the adhesive is also required to have resistance to heat and humidity during retort treatment and boiling treatment for sterilizing microorganisms adhering to and mixed in the food. If the heat resistance and adhesiveness of the adhesive are insufficient, the adhesive layer may peel off (delamination) during the retort treatment or boiling treatment.

Japanese Unexamined Patent Publication No. 2006-341423 Japanese Unexamined Patent Publication No. 2003-13032

The present invention has been made in view of such circumstances, and can be used for packaging materials mainly for foods and barrier films for electronic materials such as solar cells and display elements, and has excellent gas barrier function and heat resistance. It is an object of the present invention to provide a two-component adhesive, a polyisocyanate composition for the two-component type, a laminate, and a packaging material, which are also excellent in the above.

The present invention includes a polyol composition (A) and a polyisocyanate composition (B), and the polyol composition (A) is a polyvalent carboxylic acid (a1) containing an ortho-oriented polyvalent carboxylic acid. It contains a polyester polyol (A1) which is a reaction product with a valent alcohol (a2), and the polyisocyanate composition (B) is a polyester polyisocyanate (B1), a polyphenylene polymethylene polyisocyanate (B2), and a diphenylmethane diisocyanate (B2). A polyester polyol (B1') containing B3) and a polyester polyisocyanate (B1), which is a reaction product of a polyvalent carboxylic acid (b1) containing an aromatic polyvalent carboxylic acid and a polyhydric alcohol (b2). ) And diphenylmethane diisocyanate (B1 ″).

Further, the present invention relates to a polyisocyanate composition for such a two-component adhesive, a laminate obtained by using such a two-component adhesive, and a packaging material obtained by using the laminate.

According to the two-component adhesive of the present invention, it is possible to obtain a two-component adhesive having excellent gas barrier function and excellent heat resistance, the polyisocyanate composition for two-component type, a laminate, and a packaging material.

<Two-component adhesive>
The two-component adhesive of the present invention contains a polyol composition (A) and a polyisocyanate composition (B).

(Polyform composition (A))
The polyol composition (A) used in the present invention contains a resin (polyol) having substantially two or more hydroxyl groups. Since the time required for synthesis is short and the handling is easy, it is preferable to use a polyol having a number average molecular weight of 300 or more and 3000 or less, and more preferably 350 or more and 1000 or less. In the present invention, the number average molecular weight (Mn) is a value measured by gel permeation chromatography (GPC) under the following conditions.

Measuring device; HLC-8220GPC manufactured by Tosoh Corporation
Column; TSK-GUARDCOULUMN SuperHZ-L manufactured by Tosoh Corporation
+ TSK-GEL SuperHZM-M x 4 manufactured by Tosoh Corporation
Detector; RI (Differential Refractometer)
Data processing; Multi-station GPC-8020modelII manufactured by Tosoh Corporation
Measurement conditions; column temperature 40 ° C
Solvent tetrahydrofuran
Flow velocity 0.35 ml / min Standard; Monodisperse polystyrene sample; 0.2 mass% tetrahydrofuran solution in terms of resin solid content filtered through a microfilter (100 μl)

Examples of the polyol include a polyol having a polyester skeleton, a polyol having a polyurethane skeleton, a polyol having a polyether skeleton, and a polyol having an acrylic skeleton. Polyester, which is a polycondensate of polyvalent carboxylic acid (a1) and polyhydric alcohol (a2), in order to impart gas barrier properties to the adhesive and to make the gas barrier multilayer film described later have excellent heat resistance. It preferably contains a polyol (A1) having a skeleton. Hereinafter, the polyol (A1) having a polyester skeleton is also simply referred to as a polyester polyol (A1).

The polyvalent carboxylic acid (a1) preferably contains an ortho-oriented polyvalent carboxylic acid. Examples of the ortho-oriented polyvalent carboxylic acid include orthophthalic acid or its acid anhydride, naphthalene 2,3-dicarboxylic acid or its acid anhydride, naphthalene 1,2-dicarboxylic acid or its acid anhydride, and anthraquinone 2,3-dicarboxylic acid. Examples thereof include an acid or an acid anhydride thereof, and 2,3-anthracenecarboxylic acid or an acid anhydride thereof. These compounds may have a substituent on any carbon atom of the aromatic ring. Examples of the substituent include a chloro group, a bromo group, a methyl group, an ethyl group, an i-propyl group, a hydroxyl group, a methoxy group, an ethoxy group, a phenoxy group, a methylthio group, a phenylthio group, a cyano group, a nitro group and an amino group. Examples thereof include a phthalimide group, a carboxyl group, a carbamoyl group, an N-ethylcarbamoyl group, a phenyl group or a naphthyl group. Of these, it is preferable to use orthophthalic acid and orthophthalic anhydride. Two or more of these compounds may be used in combination.

The polyester polyol (A1) obtained by using an ortho-oriented polyvalent carboxylic acid as the polyvalent carboxylic acid (a1) is excellent in gas barrier property and adhesiveness. It is presumed that the reason why the gas barrier property is excellent is that the rotation of the polyester chain is suppressed by the skeleton derived from the ortho-oriented polyvalent carboxylic acid. It is presumed that the reason why the adhesiveness is excellent is that the polyester chain exhibits non-crystallinity due to the asymmetry, and sufficient substrate adhesion is imparted.

The polyvalent carboxylic acid (a1) may contain a polyvalent carboxylic acid other than the ortho-oriented polyvalent carboxylic acid as long as the effects of the present invention are not impaired. Specifically, aliphatic polyvalent carboxylic acids such as succinic acid, adipic acid, azelaic acid, sebacic acid, and dodecandicarboxylic acid; unsaturated bond-containing polyvalent carboxylic acids such as maleic anhydride, maleic acid, and fumaric acid; , 3-Cyclopentanedicarboxylic acid, 1,4-cyclohexanedicarboxylic acid and other alicyclic polyvalent carboxylic acids; terephthalic acid, isophthalic acid, pyromellitic acid, trimellitic acid, 1,4-naphthalenedicarboxylic acid, 2,5 -Naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, 1,8-naphthalic acid, biphenyldicarboxylic acid, diphenylic acid and its acid anhydride, 1,2-bis (phenoxy) ethane-p, p'-dicarboxylic acid and Aromatic polyvalent carboxylic acids such as acid anhydrides or ester-forming derivatives of these dicarboxylic acids, p-hydroxybenzoic acid, p- (2-hydroxyethoxy) benzoic acid and ester-forming derivatives of these dihydroxycarboxylic acids Can be mentioned. Two or more of these compounds may be used in combination. Of these, succinic acid, adipic acid, 1,3-cyclopentanedicarboxylic acid, isophthalic acid, 2,6-naphthalenedicarboxylic acid, 1,8-naphthalic acid, and diphenic acid are preferable.

The ratio of the ortho-oriented polyvalent carboxylic acid to the polyvalent carboxylic acid (a1) is appropriately adjusted according to the required gas barrier property, but is preferably 70% by mass or more. The total amount of the polyvalent carboxylic acid (a1) may be an ortho-oriented polyvalent carboxylic acid.

Conventionally known polyhydric alcohols (a2) can be used without particular limitation, and specifically, ethylene glycol, propylene glycol, butylene glycol, neopentyl glycol, cyclohexanedimethanol, 1,5-pentanediol, 3-. Aliphatics such as methyl-1,5-pentanediol, 1,6-hexanediol, methylpentanediol, dimethylbutanediol, butylethylpropanediol, diethylene glycol, triethylene glycol, tetraethylene glycol, dipropylene glycol, and tripropylene glycol. Diols; trifunctional or higher functional alcohols such as glycerin, trimethylolpropane, trimethylolethane, 1,2,4-butanetriol, pentaerythritol, dipentaerythritol; hydroquinone, resorcinol, catechol, naphthalenediol, biphenol, bisphenol A , Bisphenol F, tetramethylbiphenol, and aromatic polyhydric phenols such as ethylene oxide extenders and hydrogenated alicyclic groups. Two or more of these compounds may be used in combination. It is presumed that the smaller the number of carbon atoms between oxygen atoms, the less flexible the molecular chain is and the more difficult it is for oxygen to permeate. Therefore, it is composed of ethylene glycol, propylene glycol, butylene glycol, neopentyl glycol, and cyclohexanedimethanol. It is preferable to contain at least one selected from the group, and it is particularly preferable to use ethylene glycol.

Alternatively, the polyhydric alcohol (a2) may contain a polyhydric alcohol having a polymerizable carbon-carbon double bond such as 2-butene-1,4-diol. In this case, the gas barrier property can be improved by cross-linking between the polymerizable double bonds.

The polyhydric alcohol (a2) contains an alkylene oxide adduct of isocyanuric acid such as 1,3,5-tris (2-hydroxyethyl) isocyanuric acid and 1,3,5-tris (2-hydroxypropyl) isocyanuric acid. You may.

The isocyanul ring is highly polar and does not form hydrogen bonds. Generally, as a method for improving adhesiveness, a method of blending a highly polar functional group such as a hydroxyl group, a urethane bond, a ureido bond, or an amide bond is known. However, resins having these bonds tend to form intermolecular hydrogen bonds and may impair the solubility in organic solvents such as ethyl acetate and 2-butanone, which are often used in solvent-based adhesives. Since the polyester polyol (A1) having a ring does not impair its solubility, it can be easily diluted with an organic solvent.

Further, since the isocyanul ring is trifunctional, the polyester polyol (A1) having a polyester skeleton having the isocyanul ring as the center of the resin skeleton and having a structure derived from an ortho-oriented polyvalent carboxylic acid in its branched chain has a high crosslink density. Can be obtained. It is presumed that by increasing the crosslink density, the gap through which a gas such as oxygen passes can be reduced. As described above, it is presumed that the isocyanul ring has high polarity and a high crosslink density without forming an intermolecular hydrogen bond, so that gas barrier properties and adhesiveness can be ensured.

The glass transition temperature of the polyester polyol (A1) is preferably −30 ° C. or higher and 80 ° C. or lower, more preferably 0 ° C. or higher and 60 ° C. or lower, and further preferably 25 ° C. or higher and 60 ° C. or lower. If the glass transition temperature exceeds 80 ° C., the flexibility of the polyester polyol (A1) near room temperature is low, so that the adhesion to the substrate is poor and the adhesiveness may be lowered. On the other hand, if the temperature is lower than -30 ° C, the molecular motion of the polyester polyol (A1) at around room temperature is intense, so that sufficient gas barrier properties may not be obtained.

The polyester polyol (A1) is a polyester obtained by converting a polyester polyol, which is a reaction product of a polyvalent carboxylic acid (a1) and a polyhydric alcohol (a2), into a number average molecular weight of 1000 to 15000 by urethane elongation due to a reaction with a diisocyanate compound. It may be a polyurethane polyol. Since the urethane-extended polyester polyol (A1) has a molecular weight component of a certain level or more and a urethane bond, it has excellent gas barrier properties, excellent initial cohesive force, and is excellent as an adhesive for laminating.

The hydroxyl value of the polyester polyol (A1) is preferably 20 mgKOH / g or more and 400 mgKOH / g or less. If the hydroxyl value is less than 20 mgKOH / g, the viscosity of the polyester polyol (A1) becomes high, and good coating suitability may not be obtained. When the hydroxyl value exceeds 400 mgKOH / g, the crosslink density of the cured coating film becomes too high, and good adhesive strength may not be obtained. The hydroxyl value of the polyester polyol (A1) can be measured by the hydroxyl value measuring method described in JIS-K0070.

The acid value of the polyester polyol (A1) is preferably 200 mgKOH / g or less. If the acid value exceeds 200 mgKOH / g, the reaction with polyisocyanate may be too rapid and good coating suitability may not be obtained. The lower limit of the acid value of the polyester polyol (A1) is not particularly limited, and may be 0 mgKOH / g. The acid value of the polyester polyol (A1) can be measured by the acid value measuring method described in JIS-K0070.

When the adhesive of the present invention is a solvent-free type, the polyester polyol (A1) is preferably linear. In the present specification, the fact that the polyester polyol (A1) is linear means that the raw materials of the polyester polyol (polyvalent carboxylic acid (a1) and polyhydric alcohol (a2)) are all composed of bifunctional compounds. For example, as the polyhydric alcohol (a2), a polyester polyol (A1) prepared by using a bifunctional alcohol having a branched alkyl group such as neopentyl glycol is linearly contained. As a result, it is possible to suppress an increase in the viscosity of the polyester polyol (A1) and obtain an adhesive having excellent coatability.

When the adhesive of the present invention is a solvent type, the viscosity of the polyol composition (A) can be adjusted by an organic solvent, so that the polyester polyol (A1) does not necessarily have to be linear.

In the polyol composition (A), in addition to the polyester polyol (A1), other components such as low molecular weight alcohol, organic solvent, viscosity modifier, silane coupling agent, defoaming agent, tackifier and the like are added as required. It may be included.

Low molecular weight alcohols include ethylene glycol, glycerin, 1,3-butanediol, 1,4-butanediol, 2-methylpentane-2,4-diol, 3-methyl1,5-pentanediol, diacetin, and caprylic acid. Examples thereof include propyl, castor oil, polyethylene glycol and polypropylene glycol.

Examples of the organic solvent include toluene, xylene, methylene chloride, tetrahydrofuran, methyl acetate, ethyl acetate, n-propyl acetate, n-butyl acetate, acetone, methyl ethyl ketone (MEK), cyclohexanone, toluol, xylol, n-hexane, cyclohexane and the like. Can be mentioned.

Examples of the viscosity modifier include dimethyl phthalate, dibutyl phthalate, dimethoxyethyl phthalate, dioctyl phthalate, diphenyl phthalate, triacetin, propyl dicaprylate, and propylene carbonate.

Examples of the silane coupling agent include γ-aminopropyltriethoxysilane, γ-aminopropyltrimethoxysilane, N-β (aminoethyl) -γ-aminopropyltrimethoxysilane, and N-β (aminoethyl) -γ. Aminosilanes such as −aminopropyltrimethyldimethoxysilane, N-phenyl-γ-aminopropyltrimethoxysilane; β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-gly Epoxysilanes such as sidoxypropyltriethoxysilane and glycidoxyoctyltrimethoxysilane; vinyltris (β-methoxyethoxy) silane, vinyltriethoxysilane, vinyltrimethoxysilane, octenyltrimethoxysilane, γ-methacryloxypropyltri Vinyl silanes such as methoxysilane and methacryloxyoctyltrimethoxysilane; polymer-type epoxysilanes in which multiple alkoxysilyl groups and multiple epoxy groups are introduced into the polymer skeleton, and multiple alkoxysilyl groups and multiple amino groups introduced into the polymer skeleton. Polymer-type silane coupling agents such as polymer-type aminosilanes; hexamethyldisilazane, γ-mercaptopropyltrimethoxysilane, 3-isocyanuppropyltriethoxysilane and the like can be mentioned. Two or more of these silane coupling agents may be used in combination.

A known defoaming agent can be used and is not particularly limited, but as an example, a part of the methyl group of dimethylpolysiloxane or dimethylpolysiloxane is carbinol group, polyether group, and has 2 or more carbon atoms. Examples thereof include silicone-based defoamers modified with an alkyl group, an epoxy group, an amino group and the like, long-chain alcohols such as octyl alcohol, and sorbitan derivatives such as sorbitan monooleate.

Examples of the tackifier include a rosin-based or rosin ester-based tackifier, a terpene-based or terpene-phenol-based tackifier, a saturated hydrocarbon resin, a kumaron-based tackifier, a kumaron-inden-based tackifier, and a styrene resin-based tackifier. Examples thereof include a pressure-sensitive adhesive, a xylene resin-based pressure-sensitive adhesive, a phenol-resin-based pressure-sensitive adhesive, and a petroleum resin-based pressure-sensitive adhesive. These may be used in combination of two or more.

(Polyisocyanate composition (B))
The polyisocyanate composition (B) of the present invention contains a polyester polyisocyanate (B1), a polyphenylene polymethylene polyisocyanate (B2), and a diphenylmethane diisocyanate (B3).

The polyester polyisocyanate (B1) is a polyester polyol (B1') which is a reaction product of a polyvalent carboxylic acid (b1) containing an aromatic ring polyvalent carboxylic acid and a polyhydric alcohol (b2), and a diphenylmethane diisocyanate (diphenylmethane diisocyanate). It is a reaction product with B1'').

As the aromatic polyvalent carboxylic acid used as the polyvalent carboxylic acid (b1), conventionally known ones can be used without particular limitation, and specifically, orthophthalic acid, terephthalic acid, isophthalic acid, pyromellitic acid and trimellitic acid. , 1,4-Naphthalenedicarboxylic acid, 2,5-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, naphthalic acid, biphenyldicarboxylic acid, 1,2-bis (phenoxy) ethane-p, p'-dicarboxylic acid and Polyvalent carboxylic acids such as these dicarboxylic acids; carboxylic acid anhydrides such as phthalic acid anhydride, 2,3-naphthalenedicarboxylic acid anhydride, trimellitic anhydride, pyromellitic anhydride; dimethylterephthalic acid, 2,6-naphthalenedicarboxylic acid Examples thereof include ester-forming derivatives of polyvalent carboxylic acids such as dimethyl acid. Two or more of these compounds may be used in combination.

Among them, the ortho-oriented polyvalent carboxylic acid, particularly orthophthalic acid and its acid anhydride, can suppress the increase in the viscosity of the polyester polyol (B1') as compared with the case where other aromatic polyvalent carboxylic acids are used, and the present invention This is preferable because it can prevent deterioration of coatability when the adhesive is a solvent-free type. On the other hand, when the adhesive of the present invention is a solvent type, the viscosity of the polyisocyanate composition (B) can be adjusted by an organic solvent, so this is not the case.

As the polyvalent carboxylic acid (b1), other polyvalent carboxylic acids may be used in combination with the aromatic polyvalent carboxylic acid. Conventionally known polyvalent carboxylic acids can be used without particular limitation, and oxalic acid, malonic acid, ethylmalonic acid, dimethylmalonic acid, succinic acid, dimethylsuccinic acid, maleic acid, fumaric acid, and glutaric acid can be used in combination. , Adiponic acid, Pimelli acid, Sveric acid, Azelaic acid, Sebasic acid, Dodecandicarboxylic acid, 1,3-Cyclopentanedicarboxylic acid, 1,4-Cyclohexanedicarboxylic acid, 4-Cyclohexendicarboxylic acid, 3-Methyl-4-cyclohexene Examples thereof include 1,2-dicarboxylic acids, acid anhydrides and methyl esterified products thereof, and they can be used alone or in combination of two or more. It is preferable to use an aliphatic multivalent carboxylic acid having 8 or less carbon atoms in the portion excluding the carboxyl group.

The ratio of the aromatic polyvalent carboxylic acid in the polyvalent carboxylic acid (b1) is appropriately adjusted depending on the type of the aromatic polyvalent carboxylic acid used, the degree of gas barrier property required for the adhesive, and the coatability. 5% by mass or more, and the total amount of the polyvalent carboxylic acid (b1) may be an aromatic polyvalent carboxylic acid. By containing the aromatic multivalent carboxylic acid, the gas barrier property of the adhesive can be surely improved, so that it is more preferably 10% by mass or more. As the content of the aromatic polyvalent carboxylic acid increases, the coatability in the solvent-free type tends to decrease. Therefore, the proportion of the aromatic polyvalent carboxylic acid in the polyvalent carboxylic acid (b1) is 50% by mass. It is more preferably less than or equal to 40% by mass or less. When the adhesive of the present invention is a solvent type, the viscosity of the polyisocyanate composition (B) can be adjusted by an organic solvent, so this is not limited to this, and the aromatic polyvalent carboxylic acid in the polyvalent carboxylic acid (b1) is not limited to this. The ratio of may be 100% by mass.

As the polyhydric alcohol (b2), the same one as the polyhydric alcohol (a2) can be used, and it can be used alone or in combination of two or more. The polyhydric alcohol (b2) is preferably at least one selected from the group consisting of ethylene glycol, neopentyl glycol, and 2-methyl-1,3-propanediol.

The polyester polyol (B1'), which is a precursor of the polyester polyisocyanate (B1), is obtained by esterifying the above-mentioned multivalent carboxylic acid (b1) and polyhydric alcohol (b2) by a known and commonly used method.

The number average molecular weight of the polyester polyol (B1') is preferably 300 or more and 3000 or less, and more preferably 400 or more and 2000 or less. This makes it possible to obtain an adhesive having excellent gas barrier properties and coatability.

When the adhesive of the present invention is a solvent-free type, the polyester polyol (B1') is preferably linear. In the present specification, the fact that the polyester polyol (B1') is linear means that all the components (polyvalent carboxylic acid (b1) and polyhydric alcohol (b2)) used for its synthesis are bifunctional compounds. To say. For example, as the polyhydric alcohol (b2), a polyester polyol prepared by using a bifunctional alcohol having a branched alkyl group such as neopentyl glycol is contained linearly. As a result, it is possible to suppress an increase in the viscosity of the polyester polyisocyanate (B1), which will be described later, and to obtain an adhesive having excellent coatability.

When the adhesive of the present invention is a solvent type, the viscosity of the polyisocyanate composition (B) can be adjusted by an organic solvent, so that the polyester polyol (B1') does not necessarily have to be linear.

The diphenylmethane diisocyanate (B1'') to be reacted with the polyester polyol (B1') is 2,2'-diphenylmethane diisocyanate (hereinafter also referred to as 2,2'-MDI) and 2,4'-diphenylmethane diisocyanate (hereinafter 2,4'). It may be either −MDI) or 4,4′-diphenylmethane diisocyanate (hereinafter, also referred to as 4,4′-MDI), or two or more thereof may be used in combination. Preferably, the diphenylmethane diisocyanate (B1'') comprises 4,4'-MDI. It is preferable that 4,4'-MDI is 50% by mass or more, more preferably 75% by mass or more of diphenylmethane diisocyanate (B1 ″).

The polyester polyisocyanate (B1) contains a polyester polyol (B1') and a diphenylmethane diisocyanate (B1 ″), and the isocyanate group of the diphenylmethane diisocyanate (B1 ″) is excessive with respect to the hydroxyl group of the polyester polyol (B1 ′). It is obtained by reacting at a rate by a known and conventional method.

The polyisocyanate composition (B) of the present invention contains polyphenylene polymethylene polyisocyanate (B2). Polyphenylene polymethylene polyisocyanate is a diphenylmethane diisocyanate (MDI) -based polynuclear condensate. Mixtures of polyphenylene polymethylene polyisocyanate and MDI are also referred to as Polymeric MDI and Crude MDI. As the polyphenylene polymethylene polyisocyanate (B2), a commercially available polypeptide MDI may be used, but in that case, only the MDI-based polynuclear condensate is treated as the polyphenylene polymethylene polyisocyanate (B2).

Polyphenylene polymethylene polyisocyanate (B2) is obtained by converting an amino group of a condensation mixture (polyamine) obtained by a condensation reaction of aniline and formalin into an isocyanate group by phosgenation or the like. By changing the raw material composition ratio and reaction conditions at the time of condensation, the nucleus distribution and isomer composition ratio of the finally obtained polyphenylene polymethylene polyisocyanate (B2) can be controlled.

Further, polyphenylene polymethylene polyisocyanate (B2) is used for reaction conditions, separation conditions, etc., such as a reaction solution after conversion to an isocyanate group, removal of a solvent from the reaction solution, and a canned solution obtained by distilling and separating a part of MDI. It may be a mixture of several different types. Commercially available polyvinyl MDI may be used.

The polyphenylene polymethylene polyisocyanate (B2) preferably has an NCO% of 32% or more and 33.0% or less, more preferably 32.2% or more and 32.8% or less, and 32.6% or more and 32. It is more preferably 0.4% or less. This makes it possible to obtain an adhesive having excellent adhesiveness and heat resistance.

The polyisocyanate composition (B) of the present invention contains diphenylmethane diisocyanate (B3). The diphenylmethane diisocyanate (B3) may be any of 2,2'-MDI, 2,4'-MDI, and 4,4'-MDI, or two or more of them may be used in combination. Preferably, the diphenylmethane diisocyanate (B3) comprises 4,4'-MDI. It is preferable that 50% by mass or more of the diphenylmethane diisocyanate (B3) is 4,4'-MDI, and more preferably 75% by mass or more is 4,4'-MDI.

As the diphenylmethane diisocyanate (B3), the diphenylmethane diisocyanate (B1 ″) remaining without reacting with the polyester polyol (B1 ′) may be used as it is when preparing the polyester polyisocyanate (B1), or the polyisocyanate composition. It may be added when adjusting (B). Commercially available polypeptide MDI is a mixture of polyphenylene polymethylene polyisocyanate (B2) and MDI, and this MDI can also be used as diphenylmethane diisocyanate (B3).

The polyisocyanate composition (B) of the present invention may further contain an aliphatic isocyanate (B4) having a plurality of isocyanate groups. By using the aliphatic isocyanate (B4) in combination, the storage stability of the polyisocyanate composition (B) can be improved. Aliphatic isocyanates include butane-1,4-diisocyanate, hexamethylene diisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, 2,4,4-trimethylhexamethylene diisocyanate, xylylene diisocyanate, and m-tetramethylxylylene diisocyanate. Aliphatic diisocyanate compounds such as isocyanate;

Alicyclic diisocyanate compounds such as cyclohexane-1,4-diisocyanate, isophorone diisocyanate, lysine diisocyanate, dicyclohexylmethane-4,4'-diisocyanate, 1,3-bis (isocyanatemethyl) cyclohexane, and methylcyclohexanediisocyanate;

Adduct-modified polyisocyanate obtained by reacting a compound in which a part of the isocyanate group of these diisocyanate compounds is modified with carbodiimide, an isocyanurate-modified polyisocyanate compound of the diisocyanate compound, or a diisocyanate compound and a compound having two or more active hydrogen groups. Examples thereof include compounds, biuret-modified polyisocyanate compounds of diisocyanate compounds, allophanate-modified compounds of diisocyanate compounds, and uretdione-modified compounds of diisocyanate compounds.

Compounds having two or more active hydrogen groups that are reaction raw materials for adduct-modified polyisocyanate compounds include, for example, ethylene glycol, propylene glycol, 1,3-propanediol, 1,2,2-trimethyl-1,3-propane. Diol, 2,2-dimethyl-3-isopropyl-1,3-propanediol, 1,4-butanediol, 1,3-butanediol, 3-methyl-1,3-butanediol, 1,5-pentanediol , 3-Methyl 1,5-pentanediol, neopentyl glycol, 1,6-hexanediol, 1,4-bis (hydroxymethyl) cyclohesane, 2,2,4-trimethyl-1,3-pentanediol, trimethylol Examples thereof include propane, glycerol, erythritol, pentaerythritol, sorbitol, diethanolamine, triethanolamine, and alkylene oxide adducts of these compounds. Polyester polyol (B1') may be used. Two or more of these compounds may be used in combination.

Among them, as the aliphatic isocyanate (B4), at least one selected from the group consisting of hexamethylene diisocyanate, xylylene diisocyanate, isocyanurate-modified products of these diisocyanates, adduct-modified products, biuret-modified products, allophanate-modified products, and uretdione-modified products is selected. It is preferable to use it. Two or more of these compounds may be used in combination.

The aliphatic isocyanate (B4) may be allowed to coexist with the diphenylmethane diisocyanate (B1 ″) when the polyester polyisocyanate (B1) is prepared, or may be mixed after the adjustment. Even if the polyester polyisocyanate (B1) is prepared in the presence of the aliphatic isocyanate (B4), the diphenylmethane diisocyanate (B1 ″) preferentially reacts with the polyester polyol (B1 ′).

The polyisocyanate composition (B) may contain an isocyanate compound (B5) other than the above-mentioned (B1) to (B4) as long as the effect of the present invention is not impaired. Specific examples of such isocyanate compounds include 1,5-naphthylene diisocyanate, 4,4'-diphenyldimethylmethane diisocyanate, 4,4'-dibenzyl diisocyanate, dialkyldiphenylmethane diisocyanate, tetraalkyldiphenylmethane diisocyanate, and 1, , 3-phenylenediocyanate, 1,4-phenylenediocyanate, tolylene diisocyanate and other aromatic diisocyanate compounds, carbodiimide modified products of these diisocyanate compounds, isocyanurate modified products, adduct modified products, biuret modified products, allophanate modified products, uretdione modified products The body etc. can be mentioned. As the compound having two or more active hydrogen groups as a reaction raw material of the adduct modified product, the same compound as the aliphatic diisocyanate (B4) can be used. Two or more of these compounds may be used in combination.

The blending amount of the isocyanate compound (B5) is preferably limited to 10% by mass or less of the total amount of the isocyanate compounds (B1) to (B5), and more preferably 5% by mass or less.

The mass-based compounding ratio (B1): (B2) of the polyester polyisocyanate (B1) and the polyphenylene polymethylene polyisocyanate (B2) in the polyisocyanate composition (B) is 2: 1 to 10: 1. preferable. More preferably, it is 2.5: 1 to 7: 1.

The mass-based compounding ratio (B1): (B3) of the polyester polyisocyanate (B1) and the diphenylmethane diisocyanate (B3) in the polyisocyanate composition (B) is preferably 1: 1 to 2: 1. When it is 1.2: 1 to 1.8: 1, the coating suitability in the case of using a solvent-free adhesive becomes better.

When the polyisocyanate composition (B) contains an aliphatic isocyanate (B4), the mass-based compounding ratio (B1) of the polyester polyisocyanate (B1) and the aliphatic isocyanate (B4) in the polyisocyanate composition (B): (B4) is preferably 4: 1 or less. More preferably, it is 5: 1 to 7: 1.

By setting the blending ratio of the isocyanate compounds (B1) to (B4) in the polyisocyanate composition (B) within the above range, the crosslink density in the cured coating film of the two-component adhesive of the present invention is made suitable. It can be an adhesive having excellent adhesive strength, gas barrier property, and heat resistance.

The ratio of the isocyanate compounds (B1) to (B5) contained in the polyisocyanate composition (B) can be appropriately adjusted. The ratio of the polyester polyisocyanate (B1) to the total amount of the isocyanate compound contained in the polyisocyanate composition (B) is preferably 40% by mass or more and 65% by mass or less, and 45% by mass or more and 60% by mass or less. Is more preferable.

The ratio of polyphenylene polymethylene polyisocyanate (B2) to the total amount of the isocyanate compound contained in the polyisocyanate composition (B) is preferably 5% by mass or more and 30% by mass or less, and 7% by mass or more and 20% by mass or less. More preferably.

The ratio of diphenylmethane diisocyanate (B3) to the total amount of the isocyanate compound contained in the polyisocyanate composition (B) is preferably 15% by mass or more and 45% by mass or less, and preferably 20% by mass or more and 40% by mass or less. More preferred.

The ratio of the aliphatic isocyanate (B4) to the total amount of the isocyanate compound contained in the polyisocyanate composition (B) is preferably 15% by mass or less, and the aliphatic isocyanate (B4) may not be contained. More preferably, the proportion of the aliphatic isocyanate (B4) is 5% by mass or more and 10% by mass or less.

By setting the blending amount of the isocyanate compounds (B1) to (B4) in the polyisocyanate composition (B) within the above range, the crosslink density in the cured coating film of the two-component adhesive of the present invention is made suitable. It can be an adhesive having excellent adhesive strength, gas barrier property, and heat resistance.

The polyisocyanate composition (B) may further contain an organic solvent and a viscosity modifier. As the organic solvent and the viscosity modifier, the same ones used for the polyol composition (A) can be used.

(adhesive)
The adhesive of the present invention is a two-component adhesive containing the polyol composition (A) and the polyisocyanate composition (B) of the present invention, and is suitable for film laminating applications. Further, the adhesive of the present invention may be used in either a solvent type or a solventless type.

In the present specification, the solvent-based adhesive is a method in which an adhesive is applied to a base material, then heated in an oven or the like to volatilize the organic solvent in the coating film, and then bonded to another base material, so-called dry. A form used in the laminating method. Either one or both of the polyol composition (A) and the polyisocyanate composition (B) contains the above-mentioned organic solvent. In the case of the solvent type, the organic solvent used as the reaction medium in the production of the constituent components of the polyol composition (A) or the polyisocyanate composition (B) may be further used as a diluent in coating.

The solvent-free adhesive is a so-called non-solvent laminating method in which the adhesive is applied to a base material and then bonded to another base material without the process of heating in an oven or the like to volatilize the organic solvent. The form used. Neither the polyol composition (A) nor the polyisocyanate composition (B) substantially contains the above-mentioned organic solvent. The constituent components of the polyol composition (A) or the polyisocyanate composition (B) and the organic solvent used as the reaction medium in the production of the raw material thereof could not be completely removed, and the polyol composition (A) or the polyisocyanate composition (A) or the polyisocyanate composition ( When a small amount of organic solvent remains in B), it is understood that the organic solvent is substantially not contained. Further, when the polyol composition (A) contains a low molecular weight alcohol, the low molecular weight alcohol reacts with the polyisocyanate composition (B) and becomes a part of the coating film, so that it is not necessary to volatilize after coating. Therefore, such a form is also treated as a solvent-free adhesive.

The adhesive of the present invention is used by mixing the polyol composition (A) and the polyisocyanate composition (B) immediately before coating on the base material. The polyol composition (A) and the polyisocyanate composition (B) are equivalent ratios of the hydroxyl groups contained in the polyol composition (A) to the isocyanate groups contained in the polyisocyanate composition (B) [NCO] / [ OH] is preferably blended so as to be 0.5 to 4. If [NCO] / [OH] exceeds 4, excess isocyanate groups may bleed out from the cured coating film of the adhesive, and if it is less than 0.5, the adhesive strength may be insufficient.

The adhesive of the present invention includes inorganic fillers such as silica, alumina, aluminum flakes and glass flakes, coupling agents such as silane coupling agents and titanium coupling agents, antioxidants, heat stabilizers, ultraviolet absorbers and antistatic agents. It may contain various additives such as an inhibitor, a lubricant, an antiblocking agent, a colorant, and a crystal nucleating agent. Various thermoplastic resins such as acrylic resin, ketone resin, epoxy resin, and polyester resin may be blended for the purpose of adjusting the glass transition temperature of the cured coating film of the adhesive. These various additives and thermoplastic resins may be added in advance to either or both of the polyol composition (A) and the polyisocyanate composition (B), or the polyol composition (A) and the poly. It may be added when mixing with the isocyanate composition (B).

<Laminated body>
The laminate of the present invention can be obtained, for example, by laminating a plurality of films by a dry laminating method or a non-solvent laminating method using the adhesive of the present invention. The laminated laminate has excellent gas barrier properties and can be used as a gas barrier laminate. The film to be used is not particularly limited, and a film suitable for the intended use can be appropriately selected. For example, for food packaging, polyethylene terephthalate (PET) film, polystyrene film, polyamide film, polyacrylonitrile film, polyethylene film (LLDPE: low density polyethylene film, HDPE: high density polyethylene film) and polypropylene film (CPP: unstretched). Polypropylene film, OPP: biaxially stretched polypropylene film) and other polyolefin films, polyvinyl alcohol films, ethylene-vinyl alcohol copolymer films and the like can be mentioned.

The film may be stretched. As a stretching treatment method, one plate is to melt-extrude the resin by an extrusion film forming method or the like to form a sheet, and then perform simultaneous biaxial stretching or sequential biaxial stretching. Further, in the case of sequential biaxial stretching, it is common to first perform longitudinal stretching treatment and then lateral stretching. Specifically, a method of combining longitudinal stretching using the speed difference between rolls and transverse stretching using a tenter is often used.

Alternatively, a film in which a metal oxide such as aluminum or a metal oxide such as silica or alumina is laminated, or a barrier film containing a gas barrier layer such as polyvinyl alcohol, an ethylene / vinyl alcohol copolymer, or vinylidene chloride is used in combination. May be good. By using such a film, it is possible to obtain a laminated body having a barrier property against water vapor, oxygen, alcohol, an inert gas, a volatile organic compound (fragrance) and the like.

Various surface treatments such as flame treatment and corona discharge treatment may be performed on the surface of the film, if necessary, so that an adhesive layer without defects such as film breakage and repelling is formed.

Alternatively, the laminate of the present invention is obtained by applying the adhesive of the present invention as an adhesive (anchor coating agent) to a film with a laminator, performing a curing reaction, and then laminating a polymer material melted by an extruder. Can be obtained (extruded lamination method). As the film, the same film as that used in the above-mentioned dry laminating method and non-solvent laminating method can be used. As the polymer material to be melted, a polyolefin resin such as a low density polyethylene resin, a linear low density polyethylene resin, or an ethylene-vinyl acetate copolymer resin is preferable.

As a more specific structure of the laminated body,
(1) Base film 1 / Adhesive layer 1 / Sealant film (2) Base film 1 / Adhesive layer 1 / Metal vapor deposition unstretched film (3) Base film 1 / Adhesive layer 1 / Metal vapor deposition stretched film (4) Transparent vapor-deposited stretched film / adhesive layer 1 / sealant film (5) Base film 1 / adhesive layer 1 / base film 2 / adhesive layer 2 / sealant film (6) Base film 1 / adhesive layer 1 / metal vapor-deposited stretched film / Adhesive layer 2 / Sealant film (7) Base film 1 / Adhesive layer 1 / Transparent vapor-deposited stretched film / Adhesive layer 2 / Sealant film (8) Base film 1 / Adhesive layer 1 / Metal layer / Adhesive layer 2 / Sealant Film (9) Base film 1 / Adhesive layer 1 / Base film 2 / Adhesive layer 2 / Metal layer / Adhesive layer 3 / Sealant film (10) Base film 1 / Adhesive layer 1 / Metal layer / Adhesive layer 2 / Examples thereof include, but are not limited to, a base film 2 / an adhesive layer 3 / a sealant film.

Examples of the base film 1 used in the configuration (1) include an OPP film, a PET film, and a nylon film. Further, as the base film 1, a film having a gas barrier property and a coating for improving ink acceptability when providing a printing layer described later may be used. Examples of commercially available products of the coated base film 1 include K-OPP film and K-PET film. The adhesive layer 1 is a cured coating film of the adhesive of the present invention. Examples of the sealant film include a CPP film and an LLDPE film. A printing layer may be provided on the surface of the base film 1 on the adhesive layer 1 side (when a coated film is used as the base film 1, the surface of the coating layer on the adhesive layer 1 side). The printing layer is formed by various printing inks such as gravure ink, flexo ink, offset ink, stencil ink, and inkjet ink by a general printing method conventionally used for printing on a polymer film.

Examples of the base film 1 used in the configurations (2) and (3) include an OPP film and a PET film. The adhesive layer 1 is a cured coating film of the adhesive of the present invention. As the metal-deposited unstretched film, a VM-CPP film in which a metal such as aluminum is vapor-deposited on a CPP film is used, and as a metal-deposited stretched film, a VM-OPP film in which a metal such as aluminum is vapor-deposited on an OPP film is used. Can be done. A printing layer may be provided on the surface of the base film 1 on the adhesive layer 1 side in the same manner as in the configuration (1).

Examples of the transparent vapor-deposited stretched film used in the configuration (4) include a film obtained by subjecting silica or alumina vapor deposition to an OPP film, PET film, nylon film or the like. A film coated on the vapor-deposited layer may be used for the purpose of protecting the inorganic vapor-deposited layer of silica or alumina. The adhesive layer 1 is a cured coating film of the adhesive of the present invention. Examples of the sealant film are the same as those in the configuration (1). A printing layer may be provided on the surface of the transparent vapor-deposited stretched film on the adhesive layer 1 side (in the case of using a coating on the inorganic thin-film film, the surface on the adhesive layer 1 side of the coating layer). The method of forming the print layer is the same as that of the configuration (1).

Examples of the base film 1 used in the configuration (5) include a PET film and the like. Examples of the base film 2 include a nylon film and the like. At least one of the adhesive layer 1 and the adhesive layer 2 is a cured coating film of the adhesive of the present invention. Examples of the sealant film are the same as those in the configuration (1). A printing layer may be provided on the surface of the base film 1 on the adhesive layer 1 side in the same manner as in the configuration (1).

Examples of the base film 1 of the configuration (6) include those similar to the configurations (2) and (3). Examples of the metal-deposited stretched film include a VM-OPP film and a VM-PET film in which a metal such as aluminum is vapor-deposited on an OPP film or a PET film. At least one of the adhesive layer 1 and the adhesive layer 2 is a cured coating film of the adhesive of the present invention. Examples of the sealant film are the same as those in the configuration (1). A printing layer may be provided on the surface of the base film 1 on the adhesive layer 1 side in the same manner as in the configuration (1).

Examples of the base film 1 of the configuration (7) include a PET film and the like. Examples of the transparent vapor-deposited stretched film include those similar to the configuration (4). At least one of the adhesive layers 1 and 2 is a cured coating film of the adhesive of the present invention. Examples of the sealant film are the same as those in the configuration (1). A printing layer may be provided on the surface of the base film 1 on the adhesive layer 1 side in the same manner as in the configuration (1).

Examples of the base film 1 of the configuration (8) include a PET film and the like. Examples of the metal layer include aluminum foil. At least one of the adhesive layers 1 and 2 is a cured coating film of the adhesive of the present invention. Examples of the sealant film are the same as those in the configuration (1). A printing layer may be provided on the surface of the base film 1 on the adhesive layer 1 side in the same manner as in the configuration (1).

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

When the laminate of the present invention contains at least one of a metal vapor-deposited film, a transparent vapor-deposited film, and a metal layer, the metal-deposited layer, the transparent vapor-deposited layer, and the adhesive layer in contact with the metal layer are the cured coating film of the adhesive of the present invention. Is preferable.

When the adhesive of the present invention is a solvent type, the adhesive of the present invention is applied to a film material as a base material using a roll such as a gravure roll, and the organic solvent is volatilized by heating in an oven or the like. The other base material is bonded to obtain the laminate of the present invention. It is preferable to perform an aging treatment after laminating. The aging temperature is preferably room temperature to 80 ° C., and the aging time is preferably 12 to 240 hours.

When the adhesive of the present invention is a solvent-free type, the adhesive of the present invention, which has been preheated to about 40 ° C. to 100 ° C. in advance, is applied to the film material as a base material using a roll such as a gravure roll. , Immediately attach the other base material to obtain the laminate of the present invention. It is preferable to perform an aging treatment after laminating. The aging temperature is preferably room temperature to 70 ° C., and the aging time is preferably 6 to 240 hours.

When the adhesive of the present invention is used as an adhesive auxiliary, the adhesive auxiliary of the present invention is applied to a film material as a base material using a roll such as a gravure roll, and the organic solvent is volatilized by heating in an oven or the like. After that, the laminate of the present invention is obtained by laminating the polymer material melted by an extruder.

The amount of adhesive applied is adjusted as appropriate. In the case of a solvent-based adhesive, for example, the solid content is adjusted to be ^{1 g / m 2} or more and 10 g / m ² or less, preferably 1 g / m ² or more and 5 g / m ^{2 or less.} In the case of a solvent-free adhesive, the amount of the adhesive applied is, for example, 1 g / m ² or more and 10 g / m ² or less, preferably 1 g / m ² or more and 5 g / m ² or less.

When the adhesive of the present invention is used as an adhesive auxiliary, the coating amount is, for example, 0.03 g / m ² or more and 0.09 g / m ² or less (solid content).

The laminate of the present invention may further contain another film or base material in addition to the above-mentioned configurations (1) to (10). As the other base material, in addition to the above-mentioned stretched film, unstretched film, and transparent vapor-deposited film, a porous base material such as paper, wood, or leather can also be used. The adhesive used when bonding other substrates may or may not be the adhesive of the present invention.

<Packaging material>
The laminate of the present invention can be used as a multi-layer packaging material for the purpose of protecting foods, pharmaceuticals and the like. When used as a multi-layer packaging material, its layer structure may change depending on the contents, usage environment, and usage pattern.

The packaging material of the present invention is obtained by using the laminate of the present invention, laminating the surfaces of the sealant films of the laminate so as to face each other, and then heat-sealing the peripheral end portions thereof. As a bag-making method, the laminate of the present invention is bent or overlapped so that the inner layer surface (the surface of the sealant film) faces each other, and the peripheral end thereof is, for example, a side seal type or a two-way seal type. There are three-way seal type, four-way seal type, envelope-attached seal type, gassho-attached seal type, fold-attached seal type, flat-bottom seal type, square-bottom seal type, gusset type, and other heat-seal methods. Be done. The packaging material of the present invention can take various forms depending on the contents, the environment of use, and the form of use. Free-standing packaging materials (standing pouches), etc. are also possible. As a heat sealing method, a known method such as a bar seal, a rotary roll seal, a belt seal, an impulse seal, a high frequency seal, and an ultrasonic seal can be used.

After filling the packaging material of the present invention with the contents from the opening, the opening is heat-sealed to produce a product using the packaging material of the present invention. The contents to be filled include rice confectionery, bean confectionery, nuts, biscuits / cookies, wafer confectionery, marshmallows, pies, half-baked cakes, candy, snack confectionery and other confectionery, bread, snack noodles, instant noodles, dried noodles, pasta. , Sterile packaged rice, elephant, porridge, packaged rice, staples such as cereal foods, pickles, boiled beans, natto, miso, frozen tofu, tofu, licked mushrooms, konjac, processed wild vegetables, jams, peanut cream, salads, frozen Processed agricultural products such as vegetables and processed potatoes, processed livestock products such as hams, bacon, sausages, processed chicken products, and confectionery products, fish meat hams and sausages, marine products, kamaboko, glue, boiled vegetables, sardines, salted foods, Processed marine products such as smoked salmon and spicy cod roe, peaches, tangerines, pineapples, apples, pears, cherries and other fruit meats, corn, asparagus, mushrooms, onions, carrots, radishes, potatoes and other vegetables, hamburgers, meat Prepared foods such as balls, fried fishery products, gyoza, croquette and other frozen side dishes, chilled side dishes, butter, margarine, cheese, cream, instant creamy powder, dairy products such as baby-prepared powdered milk, liquid seasonings, retorts Examples include foods such as curry and pet food. The packaging material of the present invention can also be used as a packaging material for cigarettes, disposable body warmers, pharmaceuticals such as infusion packs, cosmetics, and vacuum heat insulating materials.

Alternatively, the packaging material of the present invention may be a lid material using the laminate of the present invention.

Hereinafter, the present invention will be described with reference to Examples and Comparative Examples, but the present invention is not limited thereto. The composition and other values are based on mass unless otherwise specified.

<Preparation of polyol composition (A)>
(Polyform composition A-1)
In a polyester reaction vessel equipped with a stirrer, nitrogen gas introduction tube, Snyder tube, and condenser, 92.00 parts of ethylene glycol, 118.50 parts of phthalic anhydride, 29.23 parts of adipic acid, and 0.01 part of titanium tetraisopropoxide. Was charged and gradually heated so that the temperature of the upper part of the rectification tube did not exceed 100 ° C. to maintain the internal temperature at 220 ° C. When the acid value became 1 mgKOH / g or less, the esterification reaction was terminated to obtain a polyester polyol having a number average molecular weight of 500. The hydroxyl value was 224.4. Further, while heating at 60 ° C., 42.92 parts of triacetin was added and stirred for 1 hour to obtain a polyol composition A-1.

(Polypoly composition A-2)
64.00 parts of diethylene glycol, 24.00 parts of 2-methyl-1,3-propanediol, 12.00 parts of trimethylolpropane, adipic acid in a polyester reaction vessel equipped with a stirrer, a nitrogen gas introduction tube, a snyder tube, and a condenser. 100.00 parts were charged and gradually heated so that the temperature of the upper part of the rectification tube did not exceed 100 ° C. to maintain the internal temperature at 240 ° C. When the acid value became 1 mgKOH / g or less, the esterification reaction was terminated to obtain a polyester polyol having a number average molecular weight of 600. The hydroxyl value was 187.0. The obtained polyester polyol was used as the polyol composition A-2.

<Preparation of polyisocyanate composition (B)>
(Polyisocyanate Composition B-1)
79.10 parts of ethylene glycol, 74.06 parts of phthalic anhydride, 73.07 parts of adipic acid and 0.01 parts of titanium tetraisopropoxide in a polyester reaction vessel equipped with a stirrer, a nitrogen gas introduction tube, a snyder tube, and a condenser. Was charged and gradually heated so that the temperature of the upper part of the rectification tube did not exceed 100 ° C. to maintain the internal temperature at 220 ° C. When the acid value became 1 mgKOH / g or less, the esterification reaction was terminated to obtain a polyester intermediate B-1'with a number average molecular weight of 800.

Put 115.73 parts of 4,4'-diphenylmethane diisocyanate and 25.88 parts of isocyanurate modified hexamethylene diisocyanate into a reaction vessel equipped with a stirrer, a nitrogen gas introduction tube, a cooling condenser, and a dropping funnel and heat to 70 ° C. The mixture was stirred while stirring, and 90 parts of the polyester intermediate B-1'92.00 was added dropwise using a dropping funnel over 2 hours, and the mixture was further stirred for 4 hours. After confirming that the urethanization reaction was completed, 21.63 parts of polyphenylene polymethylene polyisocyanate and 13.83 parts of diphenylmethane diisocyanate were added and stirred for 1 hour, and 115.32 parts of ethyl acetate was added and stirred for 1 hour. , Polyisocyanate composition B-1 was obtained. The NCO% measured according to JIS-K1603 was 11.8%.

(Polyisocyanate Composition B-2)
33.64 parts of ethylene glycol, 67.67 parts of neopentyl glycol, 44.99 parts of phthalic anhydride, and 103.58 parts of adipic acid are charged in a polyester reaction vessel equipped with a stirrer, a nitrogen gas introduction pipe, a snider pipe, and a condenser. , The internal temperature was maintained at 220 ° C. by gradually heating so that the temperature of the upper part of the rectification tube did not exceed 100 ° C. When the acid value became 1 mgKOH / g or less, the esterification reaction was terminated to obtain a polyester intermediate B-2'with a number average molecular weight of 1600.

Put 115.73 parts of 4,4'-diphenylmethane diisocyanate and 25.88 parts of isocyanurate modified hexamethylene diisocyanate into a reaction vessel equipped with a stirrer, a nitrogen gas introduction tube, a cooling condenser, and a dropping funnel and heat to 70 ° C. The mixture was stirred while stirring, and 116.00 parts of the polyester intermediate B-2'116.00 was added dropwise using a dropping funnel over 2 hours, and the mixture was further stirred for 4 hours. After confirming that the urethanization reaction was completed, 23.85 parts of polyphenylene polymethylene polyisocyanate and 15.25 parts of diphenylmethane diisocyanate were added and stirred for 1 hour to obtain a polyisocyanate composition B-2. The NCO% measured according to JIS-K1603 was 17.0%.

(Polyisocyanate Composition B-3)
31.47 parts of ethylene glycol, 67.85 parts of neopentyl glycol, 22.04 parts of isophthalic acid, 127.04 parts of adipic acid are charged in a polyester reaction vessel equipped with a stirrer, a nitrogen gas introduction pipe, a snider pipe, and a condenser. , The internal temperature was maintained at 240 ° C. by gradually heating so that the temperature of the upper part of the rectification tube did not exceed 100 ° C. When the acid value became 1 mgKOH / g or less, the esterification reaction was terminated to obtain a polyester polyol intermediate B-3'with a number average molecular weight of 1600.

Put 115.73 parts of 4,4'-diphenylmethane diisocyanate in a reaction vessel equipped with a stirrer, a nitrogen gas introduction tube, a cooling condenser, and a dropping funnel, and stir while heating at 70 ° C. to stir the polyester intermediate B-3'116. 00 parts were added dropwise using a dropping funnel over 2 hours, and the mixture was further stirred for 4 hours. After confirming that the urethanization reaction was completed, 23.91 parts of polyphenylene polymethylene polyisocyanate and 15.28 parts of diphenylmethane diisocyanate were added and stirred for 1 hour to obtain a polyisocyanate composition B-3. The NCO% measured according to JIS-K1603 was 16.2%.

(Polyisocyanate Composition B-4)
Put 115.73 parts of 4,4'-diphenylmethane diisocyanate and 25.88 parts of isocyanurate modified hexamethylene diisocyanate into a reaction vessel equipped with a stirrer, a nitrogen gas introduction tube, a cooling condenser, and a dropping funnel and heat to 70 ° C. While stirring, 116.00 parts of the polyester intermediate B-3'116.00 was added dropwise using a dropping funnel over 2 hours, and the mixture was further stirred for 4 hours. After confirming that the urethanization reaction was completed, 23.91 parts of polyphenylene polymethylene polyisocyanate and 15.28 parts of diphenylmethane diisocyanate were added and stirred for 1 hour to obtain a polyisocyanate composition B-4. The NCO% measured according to JIS-K1603 was 17.0%.

(Polyisocyanate Composition B-5)
Put 115.73 parts of 4,4'-diphenylmethane diisocyanate and 25.88 parts of biuret modified hexamethylene diisocyanate into a reaction vessel equipped with a stirrer, nitrogen gas introduction tube, cooling condenser, and dropping funnel and heat to 70 ° C. After stirring, 116.00 parts of the polyester intermediate B-3'116.00 was added dropwise using a dropping funnel over 2 hours, and the mixture was further stirred for 4 hours. After confirming that the urethanization reaction was completed, 23.91 parts of polyphenylene polymethylene polyisocyanate and 15.28 parts of diphenylmethane diisocyanate were added and stirred for 1 hour to obtain a polyisocyanate composition B-5. The NCO% measured according to JIS-K1603 was 17.1%.

(Polyisocyanate Composition B-6)
Put 115.73 parts of 4,4'-diphenylmethane diisocyanate and 25.88 parts of isocyanurate modified hexamethylene diisocyanate into a reaction vessel equipped with a stirrer, a nitrogen gas introduction tube, a cooling condenser, and a dropping funnel and heat to 70 ° C. While stirring, 116.00 parts of the polyester intermediate B-3'116.00 was added dropwise using a dropping funnel over 2 hours, and the mixture was further stirred for 4 hours. After confirming that the urethanization reaction was completed, 39.00 parts of luplanate MM103 (a mixture of a carbodiimide-modified product of 4,4'-diphenylmethane diisocyanate and 4,4'-diphenylmethane diisocyanate) was added and stirred for 1 hour. A polyisocyanate composition B-6 was obtained. The NCO% measured according to JIS-K1603 was 16.8%.

(Polyisocyanate Composition B-7)
A polyester reaction vessel equipped with a stirrer, a nitrogen gas introduction tube, a snyder tube, and a condenser was charged with 144.42 parts of diethylene glycol, 162.51 parts of adipic acid, and 0.02 parts of titanium tetraisopropoxide, and the temperature of the upper part of the rectification tube was raised. The internal temperature was maintained at 220 ° C. by gradually heating so as not to exceed 100 ° C. When the acid value became 1 mgKOH / g or less, the esterification reaction was terminated to obtain a polyester intermediate B-7'with a number average molecular weight of 1400.

Put 115.73 parts of 4,4'-diphenylmethane diisocyanate and 25.88 parts of isocyanurate modified hexamethylene diisocyanate into a reaction vessel equipped with a stirrer, a nitrogen gas introduction tube, a cooling condenser, and a dropping funnel and heat to 70 ° C. While stirring, 100 parts of the polyester intermediate B-7'111.00 was added dropwise using a dropping funnel over 2 hours, and the mixture was further stirred for 4 hours. After confirming that the urethanization reaction was completed, 23.39 parts of polyphenylene polymethylene polyisocyanate and 14.96 parts of diphenylmethane diisocyanate were added and stirred for 1 hour to obtain a polyisocyanate composition B-7. The NCO% measured according to JIS-K1603 was 16.8%.

(Polyisocyanate Composition B-8)
Put 115.73 parts of 4,4'-diphenylmethane diisocyanate and 25.88 parts of isocyanurate modified hexamethylene diisocyanate into a reaction vessel equipped with a stirrer, a nitrogen gas introduction tube, a cooling condenser, and a dropping funnel and heat to 70 ° C. While stirring, 56.50 parts of polypropylene glycol (molecular weight of about 1000) and 56.50 parts of polypropylene glycol (molecular weight of about 2000) were added dropwise using a dropping funnel over 2 hours, and the mixture was further stirred for 4 hours. After confirming that the urethanization reaction was completed, 23.39 parts of polyphenylene polymethylene polyisocyanate and 15.26 parts of diphenylmethane diisocyanate were added and stirred for 1 hour to obtain a polyisocyanate composition B-8. The NCO% measured according to JIS-K1603 was 16.7%.

(Polyisocyanate Composition B-9)
48.16 parts of ethylene glycol, 62.98 parts of 2-methyl-1,3-propanediol, and 129.69 parts of adipic acid were charged in a polyester reaction vessel equipped with a stirrer, a nitrogen gas introduction pipe, a snyder pipe, and a condenser. The internal temperature was maintained at 220 ° C. by gradually heating so that the temperature of the upper part of the rectification tube did not exceed 100 ° C. When the acid value became 1 mgKOH / g or less, the esterification reaction was terminated to obtain a polyester intermediate B-9'with a number average molecular weight of 600.

Put 119.05 parts of ruplanate MI (mixture of 4,4'-diphenylmethane diisocyanate and 2,4'-diphenylmethane diisocyanate) in a reaction vessel equipped with a stirrer, a nitrogen gas introduction tube, a cooling condenser, and a dropping funnel and bring the temperature to 70 ° C. The mixture was stirred while heating, and a part of polyester intermediate B4'81.63 was added dropwise using a dropping funnel over 2 hours, and the mixture was further stirred for 4 hours to obtain a polyisocyanate composition B-9. The NCO% measured according to JIS-K1603 was 14.5%.

<Adhesive adjustment>
(Example 1)
The polyol composition (A-1) and the polyisocyanate composition (B-1) were mixed in the formulations shown in Table 1 to obtain the adhesive of Example 1.
(Example 2)-(Example 5)
The adhesive of Example 2-5 was obtained in the same manner as in Example 1 except that the polyol composition and the polyisocyanate composition to be used and their formulations were shown in Table 1.

(Comparative Example 1)-(Comparative Example 5)
The adhesive of Comparative Example 1-5 was obtained in the same manner as in Example 1 except that the polyol composition and the polyisocyanate composition to be used and their formulations were shown in Table 2.

The "blending ratio of the isocyanate compound" in Tables 1 and 2 refers to the polyester polyisocyanate (B1), the polyphenylene polymethylene polyisocyanate (B2), and the diphenylmethane diisocyanate (B3) in the isocyanate compound contained in the polyisocyanate composition (B). The compounding ratio (%) of the aliphatic isocyanate (B4). Since the polyisocyanate compositions B-7 to B-9 do not contain a compound corresponding to the polyester polyisocyanate (B1), the blending ratio is not entered in the corresponding column. The remaining amount (51.66% by mass) of the polyisocyanate composition B-7 excluding the isocyanate compounds (B2) to (B4) is the reaction product of the polyester intermediate B-7'and diphenylmethane diisocyanate (B1''). Is a polyester polyisocyanate. Similarly, the remaining amount (51.38% by mass) of the polyisocyanate composition B-8 excluding the isocyanate compounds (B2) to (B4) is the reaction product of polypropylene glycol and diphenylmethane diisocyanate (B1 ″). It is a polyether polyisocyanate, and the remaining amount (59.46% by mass) obtained by removing the isocyanate compounds (B2) to (B4) from the polyisocyanate composition B-9 is polyester intermediate B-9'and diphenylmethane diisocyanate (B1'). It is a polyester polyisocyanate which is a reaction product with').

<Manufacturing of laminate>
(Example 1)
Using a bar coater, the adhesive of Example 1 was applied to the printed surface of an OPP film (“P2161” manufactured by Toyobo Co., Ltd.) having a thickness of 20 μm so as to ^{have a coating film amount of 2.0 g / m 2 (solid content).} And dried by volatilizing the diluting solvent with a dryer set at a temperature of 70 ° C. Next, the adhesive surface of the OPP film coated with the adhesive and the vapor-deposited surface of an aluminum-deposited CPP film (manufactured by Toray Industries, Inc .: 2203, thickness 30 μm) were bonded together. Aging was carried out at 40 ° C. for 2 days to obtain a laminate A of Example 1. Next, the OPP film is a 15 μm nylon film (RT type of “Emblem ON” manufactured by Unitika Ltd.), and the aluminum-deposited CPP film is a 60 μm LLDPE film (“TUX-HC” manufactured by Mitsui Chemicals Tohcello Co., Ltd.). The laminated body B of Example 1 was obtained in the same manner as the laminated body A except that it was changed.

(Example 2)
The adhesive of Example 2 was heated to about 40 ° C., and a solvent-free test coater (manufactured by Polytype) was used on the printed surface of an OPP film (“P2161” manufactured by Toyo Spinning Co., Ltd.) having a thickness of 20 μm. Apply so that the coating film amount is 2.0 g / m ² (solid content), and then attach the vapor-deposited surface of the aluminum-deposited CPP film (manufactured by Toray Co., Ltd .: 2203, thickness 30 μm) and the adhesive-coated surface. Matched. Aging was carried out at 40 ° C. for 2 days to obtain a laminate A of Example 2. Next, the OPP film is a 15 μm nylon film (RT type of “Emblem ON” manufactured by Unitika Ltd.), and the aluminum-deposited CPP film is a 60 μm LLDPE film (“TUX-HC” manufactured by Mitsui Chemicals Tohcello Co., Ltd.). The laminated body B of Example 2 was obtained in the same manner as the laminated body A except that it was changed.

(Example 3)-(Example 5), (Comparative Example 1)-(Comparative Example 5)
Laminated bodies A and B of Examples 3-5 and Comparative Example 1-5 were obtained in the same manner as in Example 2 except that the adhesive was changed.

(Adhesive strength)
The aging-finished laminate A is cut to a width of 15 mm in parallel with the coating direction of the adhesive, and the atmosphere temperature is placed between the OPP film and the CPP film using a Tencilon universal testing machine manufactured by Orientec Co., Ltd. The peeling speed was set to 300 mm / min at 25 ° C., and the tensile strength when peeled by the 180 degree peeling method was defined as the adhesive strength. The unit is N / 15 mm.

(Oxygen permeability)
The obtained laminate A was adjusted to a size of 10 cm × 10 cm, and OX-TRAN2 / 21 (manufactured by Mocon Co., Ltd .: oxygen permeability measuring device) was used, and according to JIS-K7126 (isopressure method), 23 ° C. 0% RH. Oxygen permeability was measured in the atmosphere of. Note that RH represents humidity. The results are summarized in Tables 1 and 2. The unit is cc / m ² , day, atm.

(Boil resistance)
The obtained laminate B was adjusted to a size of 15 cm × 30 cm, bent so that LLDPE was on the inside, and heat-sealed at 1 atm at 180 ° C. for 1 second to prepare a pouch. The contents were filled with 1/1/1 sauce (meat sauce: vegetable oil: vinegar = 1: 1: 1) and treated with hot water at 98 ° C. for 1 hour. When the pouch after the treatment showed peeling between the nylon film and the LLDPE film, it was judged as x, and when the peeling did not occur, it was judged as ◯.

As is clear from Examples and Comparative Examples, the laminate obtained by using the adhesive of the present invention was excellent in adhesive strength, gas barrier property, and boil resistance. On the other hand, the laminate obtained by using the adhesive of the comparative example could not achieve both gas barrier property and boil resistance at a satisfactory level.

Claims (13)

Containing a polyol composition (A) and a polyisocyanate composition (B),
The polyol composition (A) is a polyester polyol (A1) which is a reaction product of a polyvalent carboxylic acid (a1) containing an ortho-oriented polyvalent carboxylic acid (a1') and a polyhydric alcohol (a2). Including
The polyisocyanate composition (B) is a polyester polyisocyanate (B1) and
With polyphenylene polymethylene polyisocyanate (B2),
Contains diphenylmethane diisocyanate (B3),
The polyester polyisocyanate (B1) is a polyester polyol (B1') which is a reaction product of a polyvalent carboxylic acid (b1) containing an aromatic polyvalent carboxylic acid and a polyhydric alcohol (b2), and a diphenylmethane diisocyanate (diphenylmethane diisocyanate). B1 '') reaction products der of is, the polyisocyanate composition (B) ratio of the polyester polyisocyanate based on the total amount of the isocyanate compound (B1) containing the is 65 wt% or less than 40 wt%, wherein the poly proportion of polyphenylene polymethylene polyisocyanate (B2) is 30 mass% or more and 5 mass%, 2 liquid ratio is characterized der Rukoto than 45 wt% to 15 wt% of the diphenylmethane diisocyanate (B3) Mold adhesive. The two-component adhesive according to claim 1, wherein the diphenylmethane diisocyanate (B1'') contains 4,4'-diphenylmethane diisocyanate. The two-component adhesive according to claim 2, wherein the ratio of 4,4'-diphenylmethane diisocyanate to the diphenylmethane diisocyanate (B1 ″) is 50% by mass or more and 100% by mass or less. The two-component adhesive according to any one of claims 1 to 3, wherein the ratio of the aromatic polyvalent carboxylic acid to the polyvalent carboxylic acid (b1) is 5% by mass or more and 50% by mass or less. The two-component adhesive according to any one of claims 1 to 4, wherein the multivalent carboxylic acid (b1) contains an ortho-oriented polyvalent carboxylic acid (b1'). The two-component adhesive according to any one of claims 1 to 5, wherein the diphenylmethane diisocyanate (B3) contains 4,4'-diphenylmethane diisocyanate. The two-component adhesive according to claim 6, wherein the ratio of 4,4'-diphenylmethane diisocyanate to the diphenylmethane diisocyanate (B3) is 50% by mass or more and 100% by mass or less. The two-component adhesive according to any one of claims 1 to 7, wherein the polyisocyanate composition contains an aliphatic isocyanate (B4). The aliphatic isocyanate (B4) is at least one selected from the group consisting of hexamethylene diisocyanate, xylylene diisocyanate, isocyanurate-modified products of these diisocyanates, adduct-modified products, biuret-modified products, allophanate-modified products, and uretdione-modified products. The two-component adhesive according to claim 8, which comprises. The mass-based compounding ratio (B1): (B2) of the polyester polyisocyanate (B1) and the polyphenylene polymethylene polyisocyanate (B2) in the polyisocyanate composition (B) is 2: 1 to 10: 1. Any one of claims 1 to 9, wherein the mass-based compounding ratio (B1): (B3) of the polyester polyisocyanate (B1) and the diphenylmethane diisocyanate (B3) is 1: 1 to 2: 1. The two-component adhesive according to the section. The mass-based compounding ratio (B1): (B2) of the polyester polyisocyanate (B1) and the polyphenylene polymethylene polyisocyanate (B2) in the polyisocyanate composition (B) is 2: 1 to 10: 1. The polyisocyanate composition (B) has a mass-based compounding ratio (B1): (B3) of the polyester polyisocyanate (B1) and the diphenylmethane diisocyanate (B3) of 1: 1 to 2: 1. The method according to any one of claims 8 or 9, wherein the mass-based compounding ratio (B1): (B4) of the polyester polyisocyanate (B1) and the aliphatic isocyanate (B4) is 4: 1 or less. Two-component adhesive. A laminate containing a cured coating film of the two-component adhesive according to any one of claims 1 to 11. A packaging material using the laminate according to claim 12.