JP6002984B2 - Resin composition for high solid type adhesive and adhesive - Google Patents

Description

  The present invention relates to a resin composition for a high solid type adhesive and an adhesive.

  Packaging materials such as food and beverages not only have functions such as strength, resistance to cracking, retort resistance, and heat resistance to protect the contents from various distribution, storage such as refrigeration and heat sterilization, etc. Various functions are required, such as excellent transparency so that the contents can be confirmed.

  On the other hand, when the bag is sealed by heat sealing, an unstretched polyolefin film having excellent heat processability is essential, but the unstretched polyolefin film has many functions that are insufficient as a packaging material.

  For this reason, composite flexible films in which different polymer materials are combined are widely used as the packaging material. In general, a composite flexible film is composed of a thermoplastic film layer as an outer layer having product protection, design properties, and various functions, and a thermoplastic film layer as a sealant layer. There is also a method in which a plastic plastic, an adhesive, and a thermoplastic for sealant layer are melt-extruded to form an unstretched laminated sheet and then stretched (see Patent Document 1, for example), but the adhesive is applied to the laminate film layer Thus, a dry laminating method for producing a multilayer film by adhering a sealant layer (for example, see Patent Document 2) is simple and has become mainstream. However, the adhesive used in this application generally has only a function of adhering between different films.

  In recent years, there has been a demand for further enhancement of functionality for multilayer films, with the aim of maintaining the flavor of food, retaining its contents, extending the consumption period by preventing oxidation, preventing the growth of microorganisms and molds, and deterioration of pigments. In such a case, it is widely performed that an inert gas such as nitrogen gas or carbon dioxide gas is enclosed in the package. In the case of such packages, an oxygen gas barrier function is required to prevent oxygen from entering. When imparting a barrier function to a multilayer film, unstretched polyolefin films used for the inner layer (sealant side) have poor gas barrier properties and are difficult to impart a barrier function by coating or vapor deposition. Therefore, a barrier function is often imparted to various films (polyester resins such as polyethylene terephthalate (hereinafter abbreviated as PET), polyamide resins, stretched polyolefin resins) used on the outer layer side.

  When a gas barrier function is imparted to these outer layer side films by coating, as a gas barrier coating material, vinylidene chloride having a high oxygen barrier property and a water vapor barrier property (that is, easily hindering mass transfer) has been frequently used. In addition to the problem that dioxin is generated during firing, there is a problem of yellowing when exposed to light. In addition, when a polyvinyl alcohol resin or an ethylene-polyvinyl alcohol copolymer is used as a gas barrier coating material, the gas barrier property under low humidity is high, but there is a problem that the gas barrier property under high humidity is inferior. On the other hand, a film in which a metal vapor deposition layer such as aluminum is provided as a gas barrier layer has a problem that it is opaque and the inside cannot be visually recognized, and the microwave oven cannot be used. Further, a film provided with a vapor deposition layer of a metal oxide such as silica or alumina as a gas barrier layer is expensive and has a problem that the gas barrier performance varies due to cracks and pinholes due to poor flexibility.

  On the other hand, a method of imparting a gas barrier function to an adhesive used at the time of lamination is also known. This method has an advantage that a multi-layer film for gas barrier can be produced without using a film having a special gas barrier function imparted by a process and configuration essential for producing a laminated film. On the other hand, the flexible molecular structure essential for adhesives generally has high gas permeability. For this reason, the adhesive ability and the gas barrier function are often in a trade-off relationship, and this elimination increases the technical difficulty.

  As a container using such a gas barrier barrier laminate film, for example, in Patent Document 3 and Patent Document 4, an epoxy layer between an outer layer thermoplastic film layer and a thermoplastic film layer serving as a sealant layer is used. A gas barrier laminate film bonded with an epoxy resin composition comprising a resin and an epoxy resin curing agent is described.

  However, an epoxy adhesive is hardly used as a laminate adhesive for multilayer films, while a reaction system of polyester polyol and polyisocyanate is most widely used. Therefore, in the case of switching the product number from a general-purpose adhesive, there has been a strong demand for non-epoxy adhesives from the viewpoints of commonality of solvents, mixing properties when materials remain, and the like. In addition, in the case of a bag-like container containing food as a content, materials other than epoxy-based materials have been demanded from the viewpoint of compound safety.

  Further, the adhesive may be required to further reduce the organic solvent during use. As an adhesive that does not use any organic solvent, a solventless laminating adhesive is known. In this case, a laminator dedicated to the solventless adhesive is required. Many solvent-free laminators are not widely used in Japan. Accordingly, there is a high need for an adhesive with a high resin content (high solid) that can use a dry laminator for solvent-based adhesives that is widely used in general and that requires little solvent. For example, Patent Document 5 discloses that a polyol component having a number average molecular weight of 10,000 or less and having 1.4 to 1.8 hydroxyl groups per molecule, and an isocyanate curing agent component, which require less use of an organic solvent. Although there is a description of a high solid type adhesive made of the above, there is no description that the adhesive has gas barrier properties.

  As described above, while the above barrier function is required, there is a strong demand for a low solvent due to the need for environmental load reduction such as improvement of working environment and regulation of VOC emission into the atmosphere. In addition, the present situation is that a gas barrier adhesive resin composition having a strong adhesive force and having the above functions has not been provided.

JP 2006-341423 A JP 2003-13032 A Japanese Patent No. 4092549 Japanese Patent No. 4366563 Japanese Patent No. 4530704

  The problems to be solved by the present invention include a resin composition for an adhesive that can reduce an environmental load due to the release of an organic solvent, can provide an adhesive having a gas barrier property, and a high adhesive force, and the composition. It is in providing the adhesive agent which hardens | cures.

The present inventors are adhesive resin compositions comprising a polyester polyol (A) having two or more hydroxyl groups and a polyisocyanate (B) having two or more isocyanate groups,
The above-mentioned problems have been solved by the resin composition for an adhesive, wherein the total solid content of the polyester polyol (A) and the polyisocyanate (B) is 50% by mass or more in the total mass of the resin composition for an adhesive. .

  According to the present invention, an environmental impact due to solvent discharge is reduced and a general-purpose dry laminator can be used, a gas barrier property, and an adhesive resin composition that can provide an adhesive having high adhesive strength, And an adhesive obtained by curing the composition.

[Polyester polyol having two or more hydroxyl groups (A)]
The polyester polyol (A) used in the present invention is a polyester polyol having two or more hydroxyl groups, which is obtained by polycondensation reaction between a polyvalent carboxylic acid and a polyhydric alcohol, and is an object of the present invention. There is no particular limitation as long as it can exhibit adhesiveness and gas barrier properties.

(Polyvalent carboxylic acid)
The polyester polyol (A) of the present invention is a polyvalent carboxylic acid component, specifically, an aliphatic polyvalent carboxylic acid such as succinic acid, adipic acid, azelaic acid, sebacic acid, dodecanedicarboxylic acid, etc. 1,3-cyclopentanedicarboxylic acid, 1,4-cyclohexanedicarboxylic acid and the like as the aromatic polyvalent carboxylic acid, and orthophthalic acid, terephthalic acid, isophthalic acid, pyromellitic acid, trimellitic as the aromatic polyvalent carboxylic acid 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 anhydrides or ester-forming derivatives of these dicarboxylic acids; p-hydroxybenzoic acid, p- (2 Polyhydroxy acids such as -hydroxyethoxy) benzoic acid and ester-forming derivatives of these dihydroxycarboxylic acids can be used alone or in a mixture of two or more. These acid anhydrides can also be used. Among them, succinic acid, 1,3-cyclopentanedicarboxylic acid, orthophthalic acid, an acid anhydride of orthophthalic acid, and isophthalic acid are preferable, and orthophthalic acid and its acid anhydride are more preferable in order to obtain gas barrier properties.

(Polyhydric alcohol component)
Specifically, the polyhydric alcohol used in the present invention includes, as the aliphatic diol, ethylene glycol, propylene glycol, butylene glycol, neopentyl glycol, cyclohexane dimethanol, 1,5-pentanediol, 3-methyl-1 , 5-pentanediol, 1,6-hexanediol, methylpentanediol, dimethylbutanediol, butylethylpropanediol, diethylene glycol, triethylene glycol, tetraethylene glycol, dipropylene glycol, tripropylene glycol, aromatic polyphenol , Hydroquinone, resorcinol, catechol, naphthalene diol, biphenol, bisphenol A, hisphenol F, tetramethylbiphenol, ethylene oxide De extension product, there can be mentioned hydrogenated alicyclic. In particular, the smaller the number of carbon atoms between oxygen atoms, the less likely the molecular chain to become excessively flexible and less oxygen permeation. Therefore, ethylene glycol, propylene glycol, butylene glycol, neopentyl glycol, and cyclohexane Methanol is preferred, and ethylene glycol is more preferred. The polycondensation reaction between the polyvalent carboxylic acid and the polyhydric alcohol can be performed by a known and commonly used method.

As the polyester polyol (A) having two or more hydroxyl groups of the present invention, more specifically,
A polyester polyol (A1) obtained by reacting a carboxylic acid anhydride or a polycarboxylic acid with a polyester polyol having three or more hydroxyl groups,
A polyester polyol (A2) having a polymerizable carbon-carbon double bond,
A polyester polyol (A3) having a glycerol skeleton,
A polyester polyol (A4) obtained by polycondensation of an ortho-oriented polyvalent carboxylic acid component and a polyhydric alcohol component,
-Polyester polyol (A5) having an isocyanuric ring,
Etc.
Hereinafter, each polyester polyol will be described.

[Polyester polyol (A1) obtained by reacting carboxylic acid anhydride or polycarboxylic acid with polyester polyol having 3 or more hydroxyl groups]
The polyester polyol (A1) used in the present invention has at least one carboxy group and two obtained by reacting a polyester polyol (I) having three or more hydroxyl groups with a carboxylic acid anhydride or a polyvalent carboxylic acid. It has the above hydroxyl groups. The polyester polyol (I) having three or more hydroxyl groups can be obtained by making a part of the polyvalent carboxylic acid or polyhydric alcohol trivalent or higher.

  As the polyhydric alcohol component and polyhydric alcohol component of the polyester polyol (A1), preferably, a polycarboxylic acid component containing at least one or more of orthophthalic acid and its anhydride, ethylene glycol, propylene glycol, butylene glycol, neopentyl Reacting a carboxylic acid anhydride or a polyvalent carboxylic acid with a polyester polyol (I) having three or more hydroxyl groups composed of a polyhydric alcohol component containing at least one selected from the group consisting of glycol and cyclohexanedimethanol And having at least one carboxy group and two or more hydroxyl groups.

(Orthophthalic acid and its anhydride)
Orthophthalic acid and its anhydride have an asymmetric structure in the skeleton. Therefore, it is presumed that the rotation of the molecular chain of the resulting polyester is suppressed, and thus it is presumed that the gas barrier property is excellent. Further, it is presumed that due to this asymmetric structure, it exhibits non-crystallinity, imparts sufficient substrate adhesion, and is excellent in adhesion and gas barrier properties. Furthermore, when used as a dry laminate adhesive, the solvent solubility, which is essential, is also high, so that it has excellent handling characteristics.

(Polyvalent carboxylic acid and other components)
When synthesizing a polyester polyol (I) having three or more hydroxyl groups, when a branched structure is introduced by a polyvalent carboxylic acid component, it is necessary to have at least a part of a trivalent or higher carboxylic acid. Examples of these compounds include trimellitic acid and its acid anhydride, pyromellitic acid and its acid anhydride, etc. In order to prevent gelation during synthesis, trivalent or higher polyvalent carboxylic acids include three. Divalent carboxylic acids are preferred.
As other components, the polyester polyol (I) of the present invention may be copolymerized with other polyvalent carboxylic acid components as long as the effects of the present invention are not impaired. Specifically, as the aliphatic polyvalent carboxylic acid, succinic acid, adipic acid, azelaic acid, sebacic acid, dodecanedicarboxylic acid, etc., as the unsaturated bond-containing polyvalent carboxylic acid, maleic anhydride, maleic acid, Fumaric acid etc., 1,3-cyclopentanedicarboxylic acid, 1,4-cyclohexanedicarboxylic acid etc. as alicyclic polyvalent carboxylic acid, terephthalic acid, isophthalic acid, pyromellitic as aromatic polyvalent carboxylic acid Acid, 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 acids and anhydrides or ester-forming derivatives of these dicarboxylic acids; p-hydroxybenzoic acid, p- (2 Polyhydroxy acids such as -hydroxyethoxy) benzoic acid and ester-forming derivatives of these dihydroxycarboxylic acids can be used alone or in a mixture of two or more. Of these, succinic acid, 1,3-cyclopentanedicarboxylic acid, and isophthalic acid are preferable.

(Polyhydric alcohol component)
The polyhydric alcohol used in the present invention preferably contains at least one selected from the group consisting of ethylene glycol, propylene glycol, butylene glycol, neopentyl glycol, and cyclohexanedimethanol. Among them, ethylene glycol is most preferably used because it is presumed that the smaller the number of carbon atoms between oxygen atoms, the less the molecular chain becomes excessively flexible and the less oxygen permeates.

(Polyhydric alcohol and other ingredients)
When synthesizing a polyester polyol (I) having three or more hydroxyl groups, when a branched structure is introduced by a polyhydric alcohol component, it is necessary to have at least part of a trihydric or higher polyhydric alcohol. Examples of these compounds include glycerin, trimethylolpropane, trimethylolethane, tris (2-hydroxyethyl) isocyanurate, 1,2,4-butanetriol, pentaerythritol, and dipentaerythritol. In order to prevent gelation, trihydric alcohol is preferable as the trihydric or higher polyhydric alcohol.
As other components, in the present invention, the above-mentioned polyhydric alcohol component may be copolymerized with other polyvalent carboxylic acid components as long as the effects of the present invention are not impaired. Specifically, as the aliphatic diol, 1,5-pentanediol, 3-methyl-1,5-pentanediol, 1,6-hexanediol, methylpentanediol, dimethylbutanediol, butylethylpropanediol, diethylene glycol, Triethylene glycol, tetraethylene glycol, dipropylene glycol, tripropylene glycol, aromatic polyphenols, hydroquinone, resorcinol, catechol, naphthalene diol, biphenol, bisphenol A, hisphenol F, tetramethylbiphenol, and ethylene Examples thereof include an oxide extension product and a hydrogenated alicyclic group.

  Next, the reaction of the polyester polyol (I) of the present invention with a carboxylic acid anhydride or a polyvalent carboxylic acid is carried out as follows.

  That is, the polyester polyol (I) can be obtained by reacting a polyvalent carboxylic acid or an acid anhydride thereof with a hydroxyl group of the polyester polyol (I). The ratio between the polyester polyol (I) and the polyvalent carboxylic acid is that 1 or more hydroxyl groups of the polyester polyol (A) after the reaction are required, so that the polyvalent carboxylic acid is 1/3 of the hydroxyl groups of the polyester polyol (I). It is preferable to react with: Although there is no restriction | limiting in the carboxylic acid anhydride or polyhydric carboxylic acid used here, when gelatinization at the time of reaction with polyhydric carboxylic acid and polyester polyol (I) is considered, it is a bivalent or trivalent carboxylic acid anhydride. Is preferably used. Divalent carboxylic acid anhydrides include succinic anhydride, maleic anhydride, 1,2-cyclohexanedicarboxylic anhydride, 4-cyclohexene-1,2-dicarboxylic anhydride, 5-norbornene-2,3-dicarboxylic acid Anhydride, phthalic anhydride, 2,3-naphthalenedicarboxylic acid anhydride and the like can be used, and trimellitic acid anhydride and the like can be used as the trivalent carboxylic acid anhydride.

  The polyester polyol (A1) preferably has a hydroxyl value of 20 to 250 mgKOH / g and an acid value of 20 to 200 mgKOH / g. The hydroxyl value can be measured by the hydroxyl value measuring method described in JIS-K0070, and the acid value can be measured by the acid value measuring method described in JIS-K0070. When the hydroxyl value is smaller than 20 mgKOH / g, the molecular weight is too large, the viscosity becomes high, and good coating suitability cannot be obtained. On the other hand, when the hydroxyl value exceeds 250 mgKOH / g, the molecular weight becomes too small, so that the crosslinking density of the cured coating film becomes too high, and good adhesive strength cannot be obtained. When the acid value is less than 20 mgKOH / g, the interaction between molecules becomes small, and good gas barrier properties and good initial cohesive force cannot be obtained. On the contrary, when the acid value exceeds 200 mgKOH / g, the reaction between the polyester polyol (A) and the polyisocyanate (B) becomes too fast, and good coating suitability cannot be obtained.

[Polyester polyol (A2) having a polymerizable carbon-carbon double bond]
Further, examples of the polyester polyol (A2) of the present invention include those having a polymerizable carbon-carbon double bond in the molecule.
The polyester polyol (A2) used in the present invention is obtained by reacting a polyvalent carboxylic acid and a polyhydric alcohol, and has a polymerizable carbon-carbon double bond as a component of the polyvalent carboxylic acid and polyhydric alcohol. Can be used to introduce a polysynthetic carbon-carbon double bond into the molecule of the polyester polyol (A2).

(Polyvalent carboxylic acid)
The polyester polyol (A2) of the present invention is a polyvalent carboxylic acid component, specifically, an aliphatic polyvalent carboxylic acid such as succinic acid, adipic acid, azelaic acid, sebacic acid, dodecanedicarboxylic acid, etc. 1,3-cyclopentanedicarboxylic acid, 1,4-cyclohexanedicarboxylic acid and the like as the aromatic polyvalent carboxylic acid, and orthophthalic acid, terephthalic acid, isophthalic acid, pyromellitic acid, trimellitic as the aromatic polyvalent carboxylic acid 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 anhydrides or ester-forming derivatives of these dicarboxylic acids; p-hydroxybenzoic acid, p- ( Polybasic acids such as 2-hydroxyethoxy) benzoic acid and ester-forming derivatives of these dihydroxycarboxylic acids can be used alone or in a mixture of two or more. These acid anhydrides can also be used. Among them, succinic acid, 1,3-cyclopentanedicarboxylic acid, orthophthalic acid, an acid anhydride of orthophthalic acid, and isophthalic acid are preferable, and orthophthalic acid and its acid anhydride are more preferable in order to obtain barrier properties.

(Polyvalent carboxylic acid having a polymerizable carbon-carbon double bond)
Maleic anhydride, maleic acid, fumaric acid, 4-cyclohexene-1,2-dicarboxylic acid and acid anhydrides thereof as polyvalent carboxylic acids having a polymerizable carbon-carbon double bond in the polyvalent carboxylic acid, 3-methyl- Examples include 4-cyclohexene-1,2-dicarboxylic acid and its anhydride. Of these, maleic anhydride, maleic acid, and fumaric acid are preferred because it is presumed that the smaller the number of carbon atoms, the more the molecular chain does not become excessively flexible and the gas hardly permeates.

(Polyhydric alcohol component)
Specifically, the polyhydric alcohol used in the present invention includes, as the aliphatic diol, ethylene glycol, propylene glycol, butylene glycol, neopentyl glycol, cyclohexane dimethanol, 1,5-pentanediol, 3-methyl-1 , 5-pentanediol, 1,6-hexanediol, methylpentanediol, dimethylbutanediol, butylethylpropanediol, diethylene glycol, triethylene glycol, tetraethylene glycol, dipropylene glycol, tripropylene glycol, aromatic polyphenol , Hydroquinone, resorcinol, catechol, naphthalene diol, biphenol, bisphenol A, hisphenol F, tetramethylbiphenol, ethylene oxide De extension product, there can be mentioned hydrogenated alicyclic. In particular, the smaller the number of carbon atoms between oxygen atoms, the less likely the molecular chain to become excessively flexible and less oxygen permeation. Therefore, ethylene glycol, propylene glycol, butylene glycol, neopentyl glycol, and cyclohexane Methanol is preferable, and ethylene glucol is more preferable.

(Polyhydric alcohol with polymerizable carbon-carbon double bond)
Examples of the polyhydric alcohol having a polymerizable carbon-carbon double bond in the polyhydric alcohol include 2-butene-1,4-diol.

  Moreover, in the said polyester polyol (A2), although the polymerizable double bond was introduce | transduced into the polyester polyol (A2) by using the polyhydric carboxylic acid and polyhydric alcohol which have a polymerizable carbon-carbon double bond, It may be a reaction between a polyester polyol having a carboxylic acid having a polymerizable double bond, or a carboxylic acid anhydride. As the carboxylic acid in this case, a carboxylic acid having a polymerizable double bond such as maleic acid, maleic anhydride or fumaric acid, an unsaturated fatty acid such as oleic acid or sorbic acid, or the like can be used. The polyester polyol in this case is preferably a polyester polyol having two or more hydroxyl groups, but it is more preferable to have three or more hydroxyl groups in consideration of molecular elongation due to crosslinking with polyisocyanate. When the polyester polyol has one or two hydroxyl groups, the polyester polyol (A2) obtained by reacting a carboxylic acid having a polysynthetic double bond has 0 or 1 hydroxyl group, and reacts with the polyisocyanate (B). It becomes difficult to cause molecular elongation due to, and it becomes difficult to obtain properties such as laminate strength, seal strength, and heat resistance as an adhesive.

  The polyester polyol (A2) preferably has a hydroxyl value of 20 to 250 mgKOH / g and an acid value of 0 to 200 mgKOH / g. The hydroxyl value can be measured by the hydroxyl value measuring method described in JIS-K0070, and the acid value can be measured by the acid value measuring method described in JIS-K0070. When the hydroxyl value is smaller than 20 mgKOH / g, the molecular weight is too large, the viscosity becomes high, and good coating suitability cannot be obtained. On the other hand, when the hydroxyl value exceeds 250 mgKOH / g, the molecular weight becomes too small, so that the crosslinking density of the cured coating film becomes too high, and good adhesive strength cannot be obtained.

  Moreover, it has the characteristics that the monomer component which has a polymerizable carbon-carbon double bond is 5-60 mass parts with respect to 100 mass parts of all the monomer components which comprise polyester polyol (A2).

  If it is lower than this range, the number of crosslinking points between the polymerizable double bonds decreases, and it becomes difficult to obtain a barrier property. This is not preferable because it is difficult to be performed.

  In the present application, the monomer component amount (double bond component ratio) having a polymerizable carbon-carbon double bond in the polyester polyol (A2) is calculated using the formula (a).

  Here, the monomer refers to the polyvalent carboxylic acid and polyhydric alcohol.

  Moreover, as polyester polyol (A2) of this invention, the well-known usual drying oil which has a carbon-carbon double bond, or semi-drying oil can be mentioned.

[Polyester polyol having glycerol skeleton (A3)]
Examples of the polyester polyol (A3) of the present invention further include a polyester polyol having a glycerol skeleton represented by the general formula (1).

(In Formula (1), R < ₁ > -R < ₃ > is respectively independently a hydrogen atom or General formula (2).

(In the formula (2), n represents an integer of 1 to 5, and X represents an optionally substituted 1,2-phenylene group, 1,2-naphthylene group, 2,3-naphthylene group, 2 Represents an arylene group selected from the group consisting of 1,3-anthraquinonediyl group and 2,3-anthracenediyl group, and Y represents an alkylene group having 2 to 6 carbon atoms). However, at least one of R _{1 to} R ₃ represents a group represented by the general formula (2). )

In the general formula (1), at least one of R ₁ , R ₂ and R ₃ needs to be a group represented by the general formula (2). Among them, it is preferable that all of R ₁ , R ₂ and R ₃ are groups represented by the general formula (2).

_Further, R 1, any one of _{R 2} and _{R 3} is a group represented by the general formula (2) _compound, R 1, _{R 2,} and any two of the general formula _{R 3} (2) Any two or more compounds of the compound represented by the general formula (2) and the compound in which all of R ₁ , R ₂ and R ₃ are groups represented by the general formula (2) are mixed. Also good.

  X is selected from the group consisting of 1,2-phenylene group, 1,2-naphthylene group, 2,3-naphthylene group, 2,3-anthraquinonediyl group, and 2,3-anthracenediyl group, The arylene group which may have is represented. When X is substituted with a substituent, it may be substituted with one or more substituents, which are attached to any carbon atom on X that is different from the free radical. Examples of the substituent include chloro group, bromo group, methyl group, ethyl group, i-propyl group, hydroxyl group, methoxy group, ethoxy group, phenoxy group, methylthio group, phenylthio group, cyano group, nitro group, amino group, Examples thereof include a phthalimide group, a carboxyl group, a carbamoyl group, an N-ethylcarbamoyl group, a phenyl group, and a naphthyl group.

  In the general formula (2), Y represents ethylene group, propylene group, butylene group, neopentylene group, 1,5-pentylene group, 3-methyl-1,5-pentylene group, 1,6-hexylene group, methylpentylene. Represents an alkylene group having 2 to 6 carbon atoms, such as a len group or a dimethyl butylene group; Among them, Y is preferably a propylene group or an ethylene group, and most preferably an ethylene group.

  The polyester resin compound having a glycerol skeleton represented by the general formula (1) is essential for glycerol, an aromatic polyvalent carboxylic acid in which the carboxylic acid is substituted in the ortho position, or an anhydride thereof, and a polyhydric alcohol component. Obtained by reacting as a component.

  The aromatic polyvalent carboxylic acid in which the carboxylic acid is substituted in the ortho position or its anhydride include orthophthalic acid or its anhydride, naphthalene 2,3-dicarboxylic acid or its anhydride, naphthalene 1,2-dicarboxylic acid or its An anhydride, anthraquinone 2,3-dicarboxylic acid or its anhydride, 2,3-anthracene carboxylic acid or its anhydride, etc. are mentioned. These compounds may have a substituent on any carbon atom of the aromatic ring. Examples of the substituent include chloro group, bromo group, methyl group, ethyl group, i-propyl group, hydroxyl group, methoxy group, ethoxy group, phenoxy group, methylthio group, phenylthio group, cyano group, nitro group, amino group, Examples thereof include a phthalimide group, a carboxyl group, a carbamoyl group, an N-ethylcarbamoyl group, a phenyl group, and a naphthyl group.

  Examples of the polyhydric alcohol component include alkylene diols having 2 to 6 carbon atoms. For example, diols such as ethylene glycol, propylene glycol, butylene glycol, neopentyl glycol, 1,5-pentanediol, 3-methyl-1,5-pentanediol, 1,6-hexanediol, methylpentanediol, dimethylbutanediol, etc. Can be illustrated.

The content of the glycerol backbone in this application, with respect to gas barrier adhesive organic resin composition total solids of the mass of the present application, residues obtained by removing R ₁ to R ₃ in the general formula (1) (C _{The amount of 3} H ₅ O ₃ = 89.07) is calculated using equation (b).

P: represents a polyester polyol (A3) having a glycerol skeleton.

  The present invention is characterized by having a glycerol residue of 5% by mass or more in the organic resin composition for gas barrier adhesives in order to exhibit high gas barrier properties.

(Method for calculating mass of solid content of organic resin composition for adhesive)
The mass excluding the mass of the diluent solvent, the mass of the volatile component contained in the curing agent, and the inorganic component from the mass part of the resin composition for adhesive is defined as the mass of the total solid content of the organic resin for adhesive.

  On the other hand, the aromatic polyvalent carboxylic acid in which the acyl group, which is a raw material of the polyester component, is substituted in the ortho position, or its anhydride has an asymmetric structure. Therefore, it is presumed that the rotation of the molecular chain of the resulting polyester is suppressed, and thus it is presumed that the gas barrier property is excellent. In addition, it is presumed that due to this asymmetric structure, the crystallinity that inhibits the adhesion to the substrate is low, so that it exhibits high solubility in solvents such as ethyl acetate and methyl ethyl ketone and is excellent in gas barrier properties.

(Polyhydric alcohol)
In the polyester polyol (A3) used in the present invention, a polyhydric alcohol component other than an alkylene diol having 2 to 6 carbon atoms may be copolymerized as a polyhydric alcohol as long as the effects of the present invention are not impaired. Specifically, aliphatic polyhydric alcohols such as glycerol, erythritol, pentaerythritol, dipentaerythritol, diethylene glycol, triethylene glycol, tetraethylene glycol, dipropylene glycol, tripropylene glycol, tetraethylene glycol, tripropylene glycol, Cycloaliphatic polyhydric alcohols such as cyclohexanedimethanol and tricyclodecanedimethanol, aromatic polyhydric phenols such as hydroquinone, resorcinol, catechol, naphthalene diol, biphenol, bisphenol A, hisphenol F, tetramethylbiphenol, or the like Examples thereof include ethylene oxide elongated products and hydrogenated alicyclic groups.

(Polyvalent carboxylic acid)
The polyester polyol (A3) of the present invention essentially comprises an aromatic polyvalent carboxylic acid in which the carboxylic acid is substituted in the ortho position or an anhydride thereof as the polyvalent carboxylic acid component, but in a range not impairing the effects of the present invention. Other polyvalent carboxylic acid components may be copolymerized. Specifically, as the aliphatic polyvalent carboxylic acid, succinic acid, adipic acid, azelaic acid, sebacic acid, dodecanedicarboxylic acid, etc., as the unsaturated bond-containing polyvalent carboxylic acid, maleic anhydride, maleic acid, Fumaric acid etc., 1,3-cyclopentanedicarboxylic acid, 1,4-cyclohexanedicarboxylic acid etc. as alicyclic polyvalent carboxylic acid, terephthalic acid, isophthalic acid, pyromellitic as aromatic polyvalent carboxylic acid Acid, trimellitic acid, 1,4-naphthalenedicarboxylic acid, 2,5-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, naphthalic acid, biphenyldicarboxylic acid, diphenic acid and its anhydride, 1,2-bis ( Phenoxy) ethane-p, p′-dicarboxylic acid and anhydrides or ester-forming derivatives of these dicarboxylic acids; Polybasic acids such as droxybenzoic acid, p- (2-hydroxyethoxy) benzoic acid and ester-forming derivatives of these dihydroxycarboxylic acids can be used alone or in a mixture of two or more.

  Of these, succinic acid, 1,3-cyclopentanedicarboxylic acid, isophthalic acid, 2,6-naphthalenedicarboxylic acid, 1,8-naphthalic acid, and diphenic acid are preferable.

[Polyester polyol (A4) obtained by polycondensation of ortho-oriented polyvalent carboxylic acid component and polyhydric alcohol component]
The polyester polyol (A4) used in the present invention comprises a polyvalent carboxylic acid component containing at least one orthophthalic acid and its anhydride, ethylene glycol, propylene glycol, butylene glycol, neopentyl glycol, and cyclohexanedimethanol. It consists of a polyhydric alcohol component containing at least one selected from the group. In particular, a polyester polyol having a content of 70 to 100% by mass of the orthophthalic acid and its anhydride with respect to all the components of the polyvalent carboxylic acid is preferable.

(Polyvalent carboxylic acid and other components)
The polyester polyol (A4) of the present invention essentially comprises the above-mentioned orthophthalic acid and its anhydride as a polyvalent carboxylic acid component. However, other polyvalent carboxylic acid components may be copolymerized within a range that does not impair the effects of the present invention. May be. Specifically, as the aliphatic polyvalent carboxylic acid, succinic acid, adipic acid, azelaic acid, sebacic acid, dodecanedicarboxylic acid, etc., as the unsaturated bond-containing polyvalent carboxylic acid, maleic anhydride, maleic acid, Fumaric acid etc., 1,3-cyclopentanedicarboxylic acid, 1,4-cyclohexanedicarboxylic acid etc. as alicyclic polyvalent carboxylic acid, terephthalic acid, isophthalic acid, pyromellitic as aromatic polyvalent carboxylic acid Acid, 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 acids and anhydrides or ester-forming derivatives of these dicarboxylic acids; p-hydroxybenzoic acid, p- (2 Polyhydroxy acids such as -hydroxyethoxy) benzoic acid and ester-forming derivatives of these dihydroxycarboxylic acids can be used alone or in a mixture of two or more. Of these, succinic acid, 1,3-cyclopentanedicarboxylic acid, and isophthalic acid are preferable.

  Examples of the polyhydric alcohol component and other components include those described above.

[Polyester polyol having an isocyanuric ring (A5)]
The polyester polyol (A) of the present invention more preferably includes a polyester polyol (A5) having an isocyanuric ring represented by the following general formula (3).

(In General Formula (3), R _{1 to} R ₃ are each independently — (CH ₂ ) _n1 —OH (where n1 represents an integer of 2 to 4), or General Formula (4)

(In General Formula (4), n2 represents an integer of 2 to 4, n3 represents an integer of 1 to 5, and X represents a 1,2-phenylene group, a 1,2-naphthylene group, or a 2,3-naphthylene group. , 2,3-anthraquinonediyl group, and 2,3-anthracenediyl group, an arylene group which may have a substituent, and Y represents an alkylene group having 2 to 6 carbon atoms. Represent)
Represents a group represented by However, at least one of R ₁ , R ₂ and R ₃ is a group represented by the general formula (4))

In the general formula (3), the alkylene group represented by — (CH ₂ ) _n1 — may be linear or branched. n1 is preferably 2 or 3, and most preferably 2.

In the said General formula (4), n2 represents the integer of 2-4, n3 represents the integer of 1-5.
X is selected from the group consisting of 1,2-phenylene group, 1,2-naphthylene group, 2,3-naphthylene group, 2,3-anthraquinonediyl group, and 2,3-anthracenediyl group, and has a substituent. Represents an arylene group which may be substituted.

  When X is substituted with a substituent, it may be substituted with one or more substituents, which are attached to any carbon atom on X that is different from the free radical. Examples of the substituent include chloro group, bromo group, methyl group, ethyl group, i-propyl group, hydroxyl group, methoxy group, ethoxy group, phenoxy group, methylthio group, phenylthio group, cyano group, nitro group, amino group, Examples thereof include a phthalimide group, a carboxyl group, a carbamoyl group, an N-ethylcarbamoyl group, a phenyl group, and a naphthyl group.

  The substituent of X is preferably a hydroxyl group, a cyano group, a nitro group, an amino group, a phthalimide group, a carbamoyl group, an N-ethylcarbamoyl group, or a phenyl group, preferably a hydroxyl group, a phenoxy group, a cyano group, a nitro group, or a phthalimide group. A phenyl group is most preferred.

  In the general formula (4), Y represents ethylene group, propylene group, butylene group, neopentylene group, 1,5-pentylene group, 3-methyl-1,5-pentylene group, 1,6-hexylene group, methylpentylene. Represents an alkylene group having 2 to 6 carbon atoms, such as a len group or a dimethyl butylene group; Among them, Y is preferably a propylene group or an ethylene group, and most preferably an ethylene group.

In the general formula (3), at least one of R ₁ , R ₂ and R ₃ is a group represented by the general formula (4). Among these, it is preferable that all of R ₁ , R ₂ and R ₃ are groups represented by the general formula (4).

_Further, R 1, _{R 2,} and the compound any one of _{R 3} is a group represented by the general formula _(4), R 1, _{R 2} and any two of the general formula _{R 3} (4) Any two or more compounds of the compound represented by the formula and the compound in which all of R ₁ , R ₂ and R ₃ are groups represented by the general formula (4) are mixed. Also good.

  The polyester polyol (A5) having an isocyanuric ring represented by the general formula (3) includes a triol having an isocyanuric ring, an aromatic polyvalent carboxylic acid in which the carboxylic acid is substituted at the ortho position, or an anhydride thereof, It is obtained by reacting a monohydric alcohol component as an essential component.

  Examples of the triol having an isocyanuric ring include alkylene oxide adducts of isocyanuric acid such as 1,3,5-tris (2-hydroxyethyl) isocyanuric acid and 1,3,5-tris (2-hydroxypropyl) isocyanuric acid. Etc.

  In addition, aromatic polyvalent carboxylic acids in which the carboxylic acid is substituted in the ortho position or anhydrides thereof include orthophthalic acid or its anhydride, naphthalene 2,3-dicarboxylic acid or its anhydride, naphthalene 1,2-dicarboxylic acid. Or its anhydride, anthraquinone 2,3-dicarboxylic acid or its anhydride, 2,3-anthracene carboxylic acid or its anhydride, etc. are mentioned. These compounds may have a substituent on any carbon atom of the aromatic ring.

  Examples of the substituent include chloro group, bromo group, methyl group, ethyl group, i-propyl group, hydroxyl group, methoxy group, ethoxy group, phenoxy group, methylthio group, phenylthio group, cyano group, nitro group, amino group, Examples thereof include a phthalimide group, a carboxyl group, a carbamoyl group, an N-ethylcarbamoyl group, a phenyl group, and a naphthyl group.

  Examples of the polyhydric alcohol component include alkylene diols having 2 to 6 carbon atoms. For example, diols such as ethylene glycol, propylene glycol, butylene glycol, neopentyl glycol, 1,5-pentanediol, 3-methyl-1,5-pentanediol, 1,6-hexanediol, methylpentanediol, dimethylbutanediol, etc. Can be illustrated.

  Among them, 1,3,5-tris (2-hydroxyethyl) isocyanuric acid or 1,3,5-tris (2-hydroxypropyl) isocyanuric acid is used as the triol compound having an isocyanuric ring, and the carboxylic acid is in the ortho position. Polyester polyol compounds having an isocyanuric ring using orthophthalic anhydride as the aromatic polyvalent carboxylic acid substituted with or an anhydride thereof and ethylene glycol as the polyhydric alcohol are particularly excellent in gas barrier properties and adhesion. .

  The isocyanuric ring is highly polar and trifunctional. Therefore, the entire system can be made highly polar and the crosslinking density can be increased. From such a viewpoint, it is preferable to contain 5 mass% or more of the isocyanuric ring with respect to the total solid content of the adhesive resin.

  The reason why the adhesive of the present invention having an isocyanuric ring can secure gas barrier properties and dry laminate adhesiveness is presumed as follows.

  The isocyanuric ring is highly polar and does not form hydrogen bonds. In general, as a technique for improving adhesiveness, a method in which a highly polar functional group such as a hydroxyl group, a urethane bond, a ureido bond or an amide bond is blended is known, but a resin having these bonds forms intermolecular hydrogen bonds. Easily and may damage the solubility in ethyl acetate and 2-butanone solvent often used in dry laminate adhesives, but polyester resins with an isocyanuric ring do not impair the solubility and can be easily diluted It is.

  In addition, since the isocyanuric ring is trifunctional, a polyester polyol compound having the isocyanuric ring as the center of the resin skeleton and a polyester skeleton having a specific structure in the branched chain can obtain a high crosslinking density. It is presumed that the gap through which a gas such as oxygen can be reduced by increasing the crosslinking density. Thus, since the isocyanuric ring is highly polar and does not form an intermolecular hydrogen bond and a high crosslink density is obtained, it is presumed that gas barrier properties and dry laminate adhesiveness can be secured.

The content of isocyanuric rings in this application should be noted, with respect to the adhesive resin total solid mass of the present application, except for _R 1 to R ₃ in the general formula (3) residues _{(C 3} N ₃ O 3 = 126 .05) is calculated using equation (c).

P: represents a polyester polyol (A5) having an isocyanuric ring.

(Adhesive resin composition organic mass total mass calculation method)
The mass excluding the mass of the diluent solvent, the mass of the volatile component contained in the curing agent, and the inorganic component from the mass part of the resin composition for a gas barrier adhesive is defined as the mass of the total organic resin solid content for the adhesive.

  The polyester polyol having an isocyanuric ring can be obtained by a known polyester production method. Specifically, it can be synthesized by a production method in which the reaction is carried out while removing produced water from the system at a reaction temperature of 200 to 220 ° C. in the presence of a catalyst.

  As a specific example, after the triol having an isocyanuric ring used as a raw material, an aromatic polycarboxylic acid in which the carboxylic acid is substituted in the ortho position, or an anhydride thereof, and a polyhydric alcohol component are collectively charged Then, the temperature is increased while stirring and mixing to cause a dehydration condensation reaction. 1 mgKOH / g or less by the acid value measurement method described in JIS-K0070, and the hydroxyl value ZmgKOH / g obtained by the hydroxyl value measurement method described in JIS-K0070 is the value on the right side of the following formula (d) (mgKOH / The target polyester polyol can be obtained by continuing the reaction until it falls within ± 5% of g).

(In formula (d), Mn represents the set number average molecular weight of a predetermined trifunctional polyester resin.)

  Alternatively, each raw material may be reacted in multiple stages. Moreover, you may prepare so that a hydroxyl value may enter into less than +/- 5%, adding the diol component which volatilized at reaction temperature.

  Examples of the catalyst used in the reaction include acids such as tin-based catalysts such as monobutyltin oxide and dibutyltin oxide, titanium-based catalysts such as tetra-isopropyl-titanate and tetra-butyl-titanate, and zirconia-based catalysts such as tetra-butyl-zirconate. A catalyst is mentioned. It is preferable to use a combination of the titanium-based catalyst such as tetra-isopropyl-titanate and tetra-butyl-titanate, which has high activity for ester reaction, and the zirconia catalyst. The catalyst amount is used in an amount of 1-1000 ppm, more preferably 10-100 ppm, based on the total mass of the reaction raw material used. If it is less than 1 ppm, it is difficult to obtain an effect as a catalyst, and if it exceeds 1000 ppm, the subsequent urethanization reaction tends to be inhibited.

  The number average molecular weight of these polyester polyols (A) is particularly preferably from 450 to 5,000 because a crosslinking density with an excellent balance between adhesion and gas barrier function can be obtained. More preferably, the number average molecular weight is 500 to 3000. Further, as the curing agent, polyisocyanate described below is most preferable, can give an appropriate reaction time, and is particularly excellent in adhesive strength and gas barrier function. When the molecular weight is less than 450, the cohesive force of the adhesive at the time of coating becomes too small, causing the problem that the film shifts during lamination or the bonded film rises. Conversely, if the molecular weight is higher than 5000, The problem is that the viscosity at the time of construction is too high to be applied, and that the lamination is impossible due to low adhesiveness. The number average molecular weight was obtained by calculation from the obtained hydroxyl value and the number of functional groups of the designed hydroxyl group.

  The polyester polyol (A) used in the present invention preferably has a glass transition temperature in the range of -30 ° C to 80 ° C. More preferably, it is 0 degreeC-60 degreeC. More preferably, it is 25 degreeC-60 degreeC. When the glass transition temperature is too higher than 80 ° C., the flexibility of the polyester polyol near room temperature is lowered, and thus the adhesiveness to the substrate may be deteriorated due to poor adhesion to the substrate. On the other hand, when the temperature is too lower than −30 ° C., there is a possibility that sufficient gas barrier properties may not be obtained due to intense molecular motion of the polyester polyol near normal temperature.

  Furthermore, a polyol having a number average molecular weight of 1000 to 15000 by urethane elongation by reaction of the polyester polyol (A) with a diisocyanate compound may be used as an adhesive. Since the polyol has a certain molecular weight component and a urethane bond, the polyol has excellent gas barrier properties, excellent initial cohesive force, and is further excellent as an adhesive used during lamination.

(Adhesive hardener)
The curing agent used in the present invention is not particularly limited as long as it is a curing agent capable of reacting with the hydroxyl group of the polyester polyol (A), and known curing agents such as polyisocyanates and epoxy compounds can be used. Among these, it is preferable to use polyisocyanate from the viewpoints of adhesiveness and retort resistance.

  Polyisocyanate compounds include aromatic and aliphatic diisocyanates and trivalent or higher polyisocyanates, which may be either low molecular compounds or high molecular compounds. For example, tetramethylene diisocyanate, hexamethylene diisocyanate, toluene diisocyanate, diphenylmethane diisocyanate, hydrogenated diphenylmethane diisocyanate, xylylene diisocyanate, hydrogenated xylylene diisocyanate, isophorone diisocyanate or trimers of these isocyanate compounds, and excess of these isocyanate compounds Amounts and, for example, ethylene glycol, propylene glycol, metaxylylene alcohol, 1,3-bishydroxyethylbenzene, 1,4-bishydroxyethylbenzene, trimethylolpropane, glycerol, pentaerythritol, erythritol, sorbitol, ethylenediamine, monoethanolamine, Diethanolamine, triethanol Examples include adducts obtained by reacting low molecular active hydrogen compounds such as amines and metaxylylenediamines and their alkylene oxide adducts, various polyester resins, polyether polyols, and high molecular active hydrogen compounds of polyamides. .

  The isocyanate compound may be a blocked isocyanate. As the isocyanate blocking agent, for example, phenols such as phenol, thiophenol, methylthiophenol, ethylthiophenol, cresol, xylenol, resorcinol, nitrophenol, chlorophenol, acetoxime, methyl ethyl ketoxime, cyclohexanone oxime oximes, methanol, Alcohols such as ethanol, propanol and butanol; halogen-substituted alcohols such as ethylene chlorohydrin and 1,3-dichloro-2-propanol; tertiary alcohols such as t-butanol and t-pentanol; Examples include lactams such as caprolactam, δ-valerolactam, γ-butyrolactam, β-propylolactam, and other aromatic amines, imides, acetylacetate. , Acetoacetic ester, active methylene compounds such as malonic acid ethyl ester, mercaptans, imines, ureas, and also such as diaryl compounds sodium bisulfite. The blocked isocyanate can be obtained by subjecting the above isocyanate compound and the isocyanate blocking agent to an addition reaction by a known and appropriate method.

  Among them, xylylene diisocyanate, aromatic diisocyanate of toluene diisocyanate, and hydrogenated xylylene diisocyanate are preferable, and metaxylylene diisocyanate and metahydrogenated xylylene diisocyanate are most preferable.

  The glass transition temperature of the cured coating film of the polyester polyol (A) and polyisocyanate (B) of the present invention is preferably in the range of −30 ° C. to 80 ° C. More preferably, it is 0 degreeC-70 degreeC. More preferably, it is 25 degreeC-70 degreeC. When the glass transition temperature is higher than 80 ° C., the flexibility of the cured coating film near room temperature becomes low, and thus the adhesiveness to the substrate may be deteriorated due to poor adhesion to the substrate. On the other hand, when it is lower than −30 ° C., there is a possibility that sufficient gas barrier properties may not be obtained due to intense molecular motion of the cured coating film at around room temperature.

  Among them, the curing agent is preferably a polyisocyanate having an aromatic ring, and if it is a polyisocyanate containing the metaxylene skeleton, the gas barrier property is improved not only by hydrogen bonding of the urethane group but also by π-π stacking of aromatic rings. It is preferable because it can be improved.

  Examples of the polyisocyanate containing a metaxylene skeleton include xylene diisocyanate trimer, burette synthesized by reaction with amine, and adduct formed by reaction with alcohol. The adduct body is more preferable because the solubility of the polyisocyanate in the organic solvent used for the dry laminate adhesive is easily obtained. As the adduct, an adduct obtained by reacting with an alcohol appropriately selected from the above low molecular active hydrogen compounds can be used. Among them, addition of ethylene oxide of trimethylolpropane, glycerol, triethanolamine, metaxylenediamine, etc. Adduct bodies with objects are particularly preferred.

  In the polyester polyol (A) and the polyisocyanate (B) curing agent, the ratio of the polyester polyol (A) and the curing agent is such that the hydroxyl group of the polyester polyol (A) and the reaction component of the curing agent are 1 / 0.5. It is preferable to mix | blend so that it may become ~ 1/10 (equivalent ratio), More preferably, it is 1 / 1-1 / 5. If the curing agent component is excessive beyond this range, the excess curing agent component may be left out and bleed out from the adhesive layer after bonding. On the other hand, if the curing agent component is insufficient, the adhesive strength is insufficient. There is a fear.

  Moreover, when carboxylic acid remains in the terminal of the polyester polyol (A) used by this invention, an epoxy compound may also be used together with polyisocyanate (B) as a hardening | curing agent. Examples of epoxy compounds include diglycidyl ether of bisphenol A and oligomers thereof, diglycidyl ether of hydrogenated bisphenol A and oligomers thereof, orthophthalic acid diglycidyl ester, isophthalic acid diglycidyl ester, terephthalic acid diglycidyl ester, and p-oxybenzoic acid diacid. Glycidyl ester, tetrahydrophthalic acid diglycidyl ester, hexahydrophthalic acid diglycidyl ester, succinic acid diglycidyl ester, adipic acid diglycidyl ester, sebacic acid diglycidyl ester, ethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, 1 , 4-Butanediol diglycidyl ether, 1,6-hexanediol diglycidyl ether and polyalkylene glycol Cole diglycidyl ethers, trimellitic acid triglycidyl ester, triglycidyl isocyanurate, 1,4-diglycidyloxybenzene, diglycidyl propylene urea, glycerol triglycidyl ether, trimethylolethane triglycidyl ether, trimethylolpropane triglycidyl ether , Pentaerythritol tetraglycidyl ether, triglycidyl ether of glycerol alkylene oxide adduct, and the like.

  When an epoxy compound is used in combination as a curing agent, a general-purpose known epoxy curing accelerator may be appropriately added for the purpose of accelerating the curing so long as the gas barrier property that is the object of the present invention is not impaired.

  A known polymerization catalyst can be used as a catalyst for promoting polymerization of a polymerizable carbon-double bond. Examples of the polymerization catalyst include transition metal complexes. Although a transition metal complex will not be specifically limited if it is a compound provided with the capability to oxidatively polymerize a polymerizable double bond, A various metal or its complex can be used. For example, metals such as cobalt, manganese, lead, calcium, cerium, zirconium, zinc, iron, copper, octyl acid, naphthenic acid, neodecanoic acid, stearic acid, resin acid, tall oil fatty acid, tung oil fatty acid, linseed oil fatty acid, A salt with soybean oil fatty acid or the like can be used. 0-10 mass parts is preferable with respect to polyester polyol (A), and, as for a transition metal complex, More preferably, it is 0-3 mass parts.

  The said hardening | curing agent can also use together the well-known hardening | curing agent or accelerator selected according to the kind. Examples of the adhesion promoter include silane coupling agents such as hydrolyzable alkoxysilane compounds, titanate coupling agents, aluminum coupling agents, and epoxy resins. Silane coupling agents and titanate coupling agents are also preferred in terms of improving the adhesive to various film materials.

(Adhesive and biological components)
If the resin component of the adhesive in the present invention contains a non-petroleum component, particularly a plant-derived component, it is preferable to be an environment-friendly material in addition to a low VOC material. In particular, as a monomer for synthesizing polyester polyol (A), ethylene glycol, glycerin, propylene glycol, butylene glycol and the like as polyhydric alcohol components, and succinic acid as a polyvalent carboxylic acid are currently commercially available at an industrial level. ing. When these monomers are used, the gas barrier function is also high and particularly preferable.

(Adhesive and other ingredients)
The adhesive of this invention may mix | blend various additives in the range which does not impair gas barrier property. Examples of additives include inorganic fillers such as silica, alumina, aluminum flakes, and glass flakes, stabilizers (antioxidants, heat stabilizers, ultraviolet absorbers, etc.), plasticizers, antistatic agents, lubricants, and antiblocking agents. Examples include agents, colorants, fillers, crystal nucleating agents and the like.

(Plate-like inorganic compound)
In the resin composition for adhesives of this invention, you may contain a plate-shaped inorganic compound.
When a plate-like inorganic compound is used in the present invention, it has an effect of improving the laminate strength and gas barrier properties of an adhesive obtained by curing a resin composition for an adhesive.

  When a plate-like inorganic compound is used in combination, the laminate strength and barrier properties are improved due to the plate shape. The charge between the layers of the plate-like inorganic compound does not greatly affect the barrier property directly, but the dispersibility to the resin composition is greatly inferior with the ionic inorganic compound or the swellable inorganic compound with respect to water, and the amount added is increased. As a result, the resin composition becomes thicker and thixotropic. On the other hand, in the case of being uncharged (nonionic) or non-swelling with respect to water, even if the addition amount is increased, it is difficult to become thickened or thixotropic, so that the coating suitability can be ensured. Examples of the plate-like inorganic compound used in the present invention include, for example, hydrous silicate (phyllosilicate mineral etc.), kaolinite-serpentine clay mineral (halloysite, kaolinite, ende Light, dickite, nacrite, etc., antigolite, chrysotile, etc.), pyrophyllite-talc group (pyrophyllite, talc, kerorai, etc.), smectite group clay minerals (montmorillonite, beidellite, nontronite, saponite, hectorite, Sauconite, stevensite, etc.), vermiculite group clay minerals (vermiculite etc.), mica or mica group clay minerals (muscovite, phlogopite etc. mica, margarite, tetrasilic mica, teniolite, etc.), chlorite group (kukeite, sudite) , Clinocroix, sha Site Nimaito etc.), hydrotalcite, tabular barium sulfate, boehmite, and aluminum polyphosphate and the like. These minerals may be natural clay minerals or synthetic clay minerals. An inorganic layered compound is used individually or in combination of 2 or more types.

Moreover, it is preferable that the plate-like inorganic compound used in the present invention is nonionic without intercalation.

  Examples of the plate-like inorganic compound used in the present invention include kaolinite-serpentine clay minerals (such as halloysite, kaolinite, enderite, dickite, nacrite, antigolite and chrysotile), and pyrophyllite. -The talc family (pyrophyllite, talc, kerolai, etc.) can be mentioned.

  Moreover, it is preferable that the plate-shaped inorganic compound used by this invention is non-swelling with respect to water.

  Examples of the plate-like inorganic compound used in the present invention include kaolinite-serpentine clay minerals (such as halloysite, kaolinite, enderite, dickite, nacrite, antigolite and chrysotile), and pyrophyllite. -Talc group (Pyrophyllite, Talc, Kerolai, etc.), Mica or Mica clay mineral (Mica, such as muscovite, phlogopite, etc.), Margarite, Tetrasilic mica, Teniolite, etc., Chlorite group (Kukueite, Sudokuite, (Clinochlor, chamosite, nimite, etc.), hydrotalcite, plate-like barium sulfate and the like.

  The average particle diameter in the present invention means a particle diameter having the highest appearance frequency when the particle size distribution of a certain plate-like inorganic compound is measured with a light scattering measurement device. The average particle diameter of the plate-like inorganic compound used in the present invention is not particularly limited, but is preferably 0.1 μm or more, and more preferably 1 μm or more. If the average particle size is 0.1 μm or less, the length of the long side is short, which causes a problem that it is difficult to improve the gas barrier function without lengthening the detour path of oxygen molecules. The side with a large average particle diameter is not particularly limited. When defects such as streaks occur on the coated surface by containing a large plate-like inorganic compound by the laminating method, a material having an average particle diameter of preferably 100 μm or less, more preferably 20 μm or less is used.

The aspect ratio of the plate-like inorganic compound used in the present invention is preferably higher in order to improve the barrier ability due to the maze effect of the gas component molecules. Specifically, it is preferably 3 or more, more preferably 10 or more, and most preferably 40 or more. Moreover, although the content rate of a plate-shaped inorganic compound is arbitrary, it is preferable that it is 50 mass parts or less. If the amount exceeds 50 parts by mass, the laminating operation may be difficult or the adhesive force may be insufficient.
The content of the inorganic compound (PWC of the blended grains) can be obtained from the following formula (e).

  A known dispersion method can be used as a method of dispersing the inorganic compound described in the present invention in the adhesive resin composition. For example, an ultrasonic homogenizer, a high-pressure homogenizer, a paint conditioner, a ball mill, a roll mill, a sand mill, a sand grinder, a dyno mill, a disperse mat, a nano mill, an SC mill, a nanomizer, and the like can be mentioned, and even more preferably, a high shear force is generated. Examples of equipment that can be used include Henschel mixer, pressure kneader, Banbury mixer, planetary mixer, two-roll, three-roll. One of these may be used alone, or two or more devices may be used in combination.

  Moreover, as a method for improving the acid resistance of the adhesive layer, a known acid anhydride can be used in combination as an additive. Examples of the acid anhydride include phthalic acid anhydride, succinic acid anhydride, het acid anhydride, hymic acid anhydride, maleic acid anhydride, tetrahydrophthalic acid anhydride, hexahydraphthalic acid anhydride, tetraprom phthalic acid Anhydride, tetrachlorophthalic anhydride, trimellitic anhydride, pyromellitic anhydride, benzophenotetracarboxylic anhydride, 2,3,6,7-naphthalenetetracarboxylic dianhydride, 5- (2 , 5-oxotetrahydrofuryl) -3-methyl-3-cyclohexene-1,2-dicarboxylic anhydride, styrene maleic anhydride copolymer and the like.

  Moreover, you may add the compound etc. which have an oxygen trap function further as needed. Examples of the compound having an oxygen scavenging function include low molecular organic compounds that react with oxygen such as hindered phenols, vitamin C, vitamin E, organic phosphorus compounds, gallic acid, pyrogallol, cobalt, manganese, nickel, iron, Examples include transition metal compounds such as copper.

  Moreover, in order to improve the adhesiveness with respect to various film materials immediately after application | coating, you may add tackifiers, such as a xylene resin, a terpene resin, a phenol resin, and a rosin resin, as needed. When adding these, the range of 0.01-5 mass parts is preferable with respect to 100 mass parts of total amounts of an epoxy resin and an epoxy resin hardening | curing agent.

  Moreover, an active energy ray can also be used as a method of reacting a polymerizable double bond. A known technique can be used as the active energy ray, and it can be cured by irradiation with ionizing radiation such as electron beam, ultraviolet ray, or γ ray. In the case of curing with ultraviolet rays, a known ultraviolet irradiation device equipped with a high pressure mercury lamp, an excimer lamp, a metal halide lamp or the like can be used.

  In the case of curing by irradiating with ultraviolet rays, if necessary, 0.1 to 20 parts by mass of a light (polymerization) initiator that generates radicals and the like by irradiation with ultraviolet rays with respect to 100 parts by mass of the polyester polyol (A). It is preferable to add a certain amount.

  Radical-generating photo (polymerization) initiators include hydrogen abstraction types such as benzyl, benzophenone, Michler's ketone, 2-chlorothioxanthone, 2,4-diethylthioxanthone, benzoin ethyl ether, diethoxyacetophenone, benzylmethyl ketal, hydroxy Examples include photocleavage types such as cyclohexyl phenyl ketone and 2-hydroxy-2-methylphenyl ketone. These can be used alone or in combination.

(Resin composition for high solid adhesive)
The resin composition for an adhesive of the present invention is a high solid type in which the total solid content of the polyester polyol (A) and the polyisocyanate (B) is 50% by mass or more in the total mass of the resin composition for an adhesive. It has the characteristics.

The mass% contained in the total amount of the resin composition for the adhesive suppresses the use of an organic solvent, and is preferably as high as possible for reducing the environmental load. However, generally, when it exceeds 80 mass%, the viscosity is improved in coating. Too much is not preferable.
In addition, if it is 50% by mass or less in the total resin composition mass, the volatile components contained must be removed, and a large amount of used organic solvent is generated, which is preferable from the viewpoint of reducing environmental burden. There is no gas barrier property.
For this reason, 50-80 mass% can be mentioned as a preferable range.

  Here, calculation of the solid content of the polyester polyol (A) and the polyisocyanate (B) is based on the mass calculation method of the solid content of the organic resin composition for an adhesive described above.

(Gas barrier function)
The resin composition for adhesives of the present invention has a gas barrier function against various gases. Examples of the gas that can be shut off include oxygen, inert gas, alcohol, and scent components.
(Target inert gas)
The inert gas that is intended to be blocked by the multilayer film of the present invention is inert to foods and is less likely to cause general chemical changes, and thus prevents contact of oxygen and water vapor around foods, etc. It is a gas useful for maintaining the flavor of food, maintaining its contents, and preventing oxidation. Specifically, in addition to nitrogen and carbon dioxide, helium, neon, argon, krypton, xenon, and radon rare gases can be exemplified. Of these, nitrogen, argon, and carbon dioxide are widely used as the inert gas.

(Target alcohol)
The alcohol targeted for blocking by the multilayer film of the present invention is a material generally classified as an alcohol having a structure in which a hydroxyl group is bonded to an alkyl chain in at least one place. There is no particular limitation. Moreover, monohydric alcohol or polyhydric alcohol can be used. Examples of the monohydric alcohol include methanol, ethanol, 1-propanol, 2-propanol, butanol, pentanol, neopentyl glycol, hexanol, benzyl alcohol, allyl alcohol, and cyclohexanol. Examples of the polyhydric alcohol include ethylene glycol, propanediol, butanediol, glycerin, and trimethylpropane. Furthermore, in addition to amino alcohols such as N, N-diethylethanolamine, N, N-dimethylethanolamine, N-methyldiethanolamine and N-ethylethanolamine, alcohol compounds containing ether groups such as diethylene glycol and triethylene glycol Etc. can also be used.

  Moreover, as the state of the alcohol compound, a material that is a gas to a liquid in a normal temperature region is preferable because of high effectiveness of the present invention.

Furthermore, the multilayer film of the present invention can be used as a scent component barrier multilayer film. The scent component to be used in the present invention is a scent contained in sanitary products including pet scents, shampoos, rinses, detergents, softeners, soaps, etc. Insect repellents, fragrances, hair dyes, perfumes, pesticides, various organic solvents, and the like can be suitably used for flexible packaging materials in fields where it is desired to prevent the release of low-molecular components.
Moreover, since the multilayer film of this invention has water vapor | steam barrier property, it can be used as a water vapor | steam barrier multilayer film.

(Adhesive form)
The adhesive of the present invention needs to be a solvent type. The solvent for the adhesive may be used as a reaction medium during the production of the polyester polyol and the curing agent. Furthermore, it is used as a diluent during painting. Solvents that can be used include, for example, esters such as ethyl acetate, butyl acetate and cellosolve acetate, ketones such as acetone, methyl ethyl ketone, isobutyl ketone and cyclohexanone, ethers such as tetrahydrofuran and dioxane, and aromatic hydrocarbons such as toluene and xylene. , Halogenated hydrocarbons such as methylene chloride and ethylene chloride, dimethyl sulfoxide, dimethyl sulfoamide and the like. Of these, it is usually preferable to use ethyl acetate or methyl ethyl ketone.

  The adhesive of the present invention can be used as an adhesive for various applications that require gas barrier properties against polymers, paper, metals, etc. as a gas barrier adhesive.

  Hereinafter, an adhesive for film lamination will be described as one of specific applications.

  The adhesive of the present invention can be used as an adhesive for film lamination. Since the laminated film is excellent in gas barrier properties, it can be used as a gas barrier laminated film.

The film for lamination used in the present invention is not particularly limited, and a thermoplastic resin film can be appropriately selected according to a desired application. For example, for food packaging, 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: Polyolefin film such as biaxially stretched polypropylene film), polyvinyl alcohol film, ethylene-vinyl alcohol copolymer film, and the like. These may be subjected to stretching treatment. As the stretching treatment method, it is common to perform simultaneous biaxial stretching or sequential biaxial stretching after the resin is melt-extruded by extrusion film forming method or the like to form a sheet. Further, in the case of sequential biaxial stretching, it is common to first perform longitudinal stretching and then perform lateral stretching. Specifically, a method of combining longitudinal stretching using a speed difference between rolls and transverse stretching using a tenter is often used. However, when a transparent vapor-deposited film having a high gas barrier property is used on both sides of the adhesive, polymerization of the polymerizable double bond of the polyester polyol (A2) as an adhesive component may be inhibited and good barrier properties may not be exhibited. is there. Therefore, as the oxygen barrier property of the laminated film for gas barrier, it is preferable that the oxygen permeability of at least one laminate film is 0.1 cc / m ² · day · atm or more.

  The adhesive of the present invention can be preferably used as an adhesive for laminated films formed by bonding a plurality of the same or different resin films. The resin film may be appropriately selected depending on the purpose. For example, when used as a packaging material, the outermost layer is a thermoplastic resin film selected from PET, OPP, and polyamide, and the innermost layer is unstretched polypropylene. (Hereinafter abbreviated as CPP), a composite film consisting of two layers using a thermoplastic resin film selected from a low density polyethylene film (hereinafter abbreviated as LLDPE), or an outermost layer selected from, for example, PET, polyamide and OPP A three-layer composite using a thermoplastic resin film, a thermoplastic resin film that forms an intermediate layer selected from OPP, PET, and polyamide, and a thermoplastic resin film that forms an innermost layer selected from CPP and LLDPE Heat to form an outermost layer selected from a film, for example, OPP, PET, polyamide Selected from a plastic film, a thermoplastic film forming a first intermediate layer selected from PET and nylon, and a thermoplastic film forming a second intermediate layer selected from PET and polyamide, LLDPE, and CPP A composite film composed of four layers using a thermoplastic resin film forming the innermost layer can be preferably used as a food packaging material as a gas barrier film.

  Moreover, you may perform various surface treatments, such as a flame treatment and a corona discharge treatment, as needed so that the adhesive layer without defects, such as a film | membrane piece and a repellency, may be formed in the film surface.

After the adhesive of the present invention is applied to one of the thermoplastic resin films, the other thermoplastic resin film is stacked and bonded together by lamination to obtain the laminated film for gas barrier of the present invention. As the lamination method, known lamination such as dry lamination, non-solvent lamination, extrusion lamination, etc. can be used.
Specifically, in the dry lamination method, the adhesive of the present invention is applied to one of the base films by the gravure roll method, and the other base film is stacked and bonded by dry lamination (dry lamination method). The temperature of the laminate roll is preferably about room temperature to 60 ° C.

  Moreover, it is preferable that the laminated | multilayer film for gas barriers of this invention perform aging after preparation. If polyisocyanate is used as a curing agent, the aging condition is from room temperature to 80 ° C., for 12 to 240 hours, during which adhesive strength is generated.

  Since the adhesive of the present invention is characterized by having a high gas barrier property, the laminate film formed by the adhesive is a PVDC coat layer, a polyvinyl alcohol (PVA) coat layer, an ethylene-vinyl alcohol copolymer ( EVOH) Film layer, metaxylylene adipamide film layer, inorganic vapor deposited film layer deposited with alumina, silica, etc. .

  In the present invention, in order to provide an even higher barrier function, a film in which a vapor-deposited layer of a metal such as aluminum or a metal oxide such as silica or alumina is laminated, polyvinyl alcohol, or ethylene / vinyl alcohol as necessary. A gas barrier function may be further increased by using a barrier film containing a gas barrier layer such as a polymer or vinylidene chloride in combination.

  Next, the present invention will be specifically described with reference to examples and comparative examples. Unless otherwise indicated, “part” and “%” are based on mass.

(Production Example 1) Production Example of Polyester Polyol (A): Gly (OPAEG) 2MA The present polyester is the main agent of an adhesive having the structures of polyesters (A1), (A2), (A3), and (A4). In a polyester reaction vessel equipped with a stirrer, a nitrogen gas introduction tube, a rectification tube, a water separator, etc., 1316.8 parts of phthalic anhydride, 573.9 parts of ethylene glycol, 409.3 parts of glycerin and titanium tetraisopropoxide are added. An amount corresponding to 100 ppm with respect to the total amount of the polyvalent carboxylic acid and the polyhydric alcohol was charged, and the inner temperature was maintained at 220 ° C. by gradually heating so that the rectifying tube upper temperature did not exceed 100 ° C. When the acid value reached 1 mgKOH / g or less, the esterification reaction was terminated to obtain a polyester polyol having a hydroxyl value of 339.9 mgKOH / g. Next, the temperature was lowered to 120 ° C., and 421.8 parts of maleic anhydride was added thereto, and maintained at 120 ° C. The esterification reaction was terminated when the acid value was approximately half of the acid value calculated from the charged amount of maleic anhydride, and the number average molecular weight was about 520, the hydroxyl value was 216.6 mgKOH / g, and the acid value was 96.2 mgKOH / g. A polyester polyol was obtained. Polyester polyol (A) Number of functional groups designed per molecule: 2 hydroxyl groups, 1 carboxy group.

Production Example 2 Production Example of Polyester Polyol (A): THEI (OPAEG) 3 This polyester is the main agent of an adhesive having the structure of polyester (A5).
In a polyester reaction vessel equipped with a stirrer, a nitrogen gas introduction tube, a rectification tube, a water separator, etc., 1136.5 parts of phthalic anhydride, 495.3 parts of ethylene glycol, 668.1 tris (2-hydroxyethyl) isocyanurate Part and titanium tetraisopropoxide are charged in an amount corresponding to 100 ppm with respect to the total amount of polyvalent carboxylic acid and polyhydric alcohol, and gradually heated so that the upper temperature of the rectification tube does not exceed 100 ° C. The temperature was kept 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 about 860, a hydroxyl value of 195.4 mgKOH / g, and an acid value of 0.9 mgKOH / g. Polyester polyol (A) Designed number of functional groups per molecule: hydroxyl groups: 3 and carboxy groups: 0.

(Production Example 3) Production Example of Polyester Polyol (A): OPAEG This polyester is a main agent of an adhesive having a structure of polyester (A4).
In a polyester reaction vessel equipped with a stirrer, a nitrogen gas introduction tube, a rectification tube, a water separator, etc., 148.1 parts of phthalic anhydride, 84.2 parts of ethylene glycol derived from plant components, and 0.03 of titanium tetraisopropoxide The inner temperature was maintained at 205 ° C. by gradually heating so that the temperature of the upper part of the rectifying tube did not exceed 100 ° C. When the acid value became 1 mgKOH / g or less, the esterification reaction was terminated to obtain an amorphous polyester polyol having a number average molecular weight of 600. This polyester polyol had a hydroxyl value of 190 mgKOH / g and an acid value of 1.0 mgKOH / g. The number of functional groups designed per molecule of the polyester polyol is: hydroxyl group: 2 and carboxy group: 0.

(Curing agent for adhesive)
“Takenate D-110N” made by Mitsui Chemicals (trimethylolpropane adduct of metaxylylene diisocyanate, non-volatile content 75% by mass) and “Takenate 500” made by Mitsui Chemicals (metaxylylene diisocyanate 100% by mass) are used alone or in combination. Used. These used amounts (compounding ratios) are shown in Table 1 with respect to the polyester polyol (A) used.

(Examples 1 to 5) High-solid type adhesive for gas barrier multilayer film According to the blending ratio of Examples 1 to 5 in Table 1, polyester polyol and curing agent were mixed to obtain a solvent-type adhesive. The adhesive was applied and laminated by the following coating method 1 to obtain a laminated film for gas barrier of the present invention. The mica used for some adhesives is mica powder “HM6040” (produced by Heng Hao, muscovite / non-swelling, interlayer ionic, plate-like, average particle size / 20 μm, aspect ratio / about 100). It is. The nonvolatile component content of each example and each evaluation result are shown in Table 1.

(Comparative Example 1)
Dick Dry LX-703VL (manufactured by DIC Graphics: polyester polyol, non-volatile content / about 62%), which is a solvent-based laminating adhesive main agent, and a solvent-based adhesive curing agent are mixed as shown in Table 2, A solvent-type adhesive was obtained. The adhesive was applied and laminated by the following coating method 1 to obtain a comparative film for the present invention.

(Coating and aging methods)
Using a bar coater, the solvent-type adhesive was coated with a polyethylene terephthalate (PET) film having a thickness of 12 μm so that the coating amount was 5.0 g / m ² (solid content) (“E-5102, manufactured by Toyobo Co., Ltd.). )) Is applied to the corona-treated surface, the diluted solvent is volatilized and dried with a dryer set at a temperature of 70 ° C., and the adhesive surface of the PET film on which the adhesive is applied and the unstretched polypropylene with a coating surface thickness of 70 μm A corona-treated surface of a (CPP) film (“ZK93KM” manufactured by Toray Industries, Inc.) was laminated to prepare a composite film having a layer configuration of PET film / adhesive layer / CPP film. Next, the composite film was aged at 40 ° C. for 3 days to cure the adhesive, and a laminated film for gas barrier using the high solid type gas barrier adhesive of the present invention was obtained.

(Evaluation method)
(1) Adhesive strength The laminated film for gas barrier that has been aged is cut into a width of 15 mm in parallel with the coating direction, and between the PET film and the CPP film using a Tensilon universal testing machine manufactured by Orientec Co., Ltd. The tensile strength at the time of peeling by the 180 ° peeling method was defined as the adhesive strength at an atmosphere temperature of 25 ° C. and a peeling speed of 300 mm / min. The unit of adhesive strength was N / 15 mm.

(2) Oxygen permeability Under the atmosphere of 23 ° C. and 90% RH, the aging-completed laminated film for the barrier is compliant with JIS-K7126 (isobaric method) using an oxygen permeability measuring device OX-TRAN2 / 21MH manufactured by Mocon. Measured with Note that RH represents humidity. In addition, the measured value on these conditions of the PET film used by each Example and the comparative example was 100 cc / m < ² > * day * atm. Further, the CPP film exceeded the measurement range of 400 cc / m ² · day · atm in this measuring apparatus and did not substantially have a barrier function.

(3) Measurement of coating viscosity The viscosity of the adhesive solution immediately before coating lamination prepared in various examples and comparative examples was measured immediately after mixing the main agent and curing agent with a RICOSHA Zahn cup viscometer # 3. It was. If the number of seconds until the adhesive completely passes by the viscometer falls within the range of 13 to 20 seconds, it means that the solvent-type adhesive has coating laminate suitability.

Table 1 shows the composition of the adhesive and the evaluation results for the film of each Example, and Table 2 shows the results of Comparative Example 1.

As described above, in Examples 1 to 5, the non-volatile component ratio is as high as 54% by mass or more, and it is suitable for coating suitability with a dry laminator in addition to being a low-VOC type adhesive that has little solvent volatilized during coating lamination. It had a Zahn cup viscosity in the range. In addition to having a high oxygen barrier function, the laminate strength was also sufficiently practical. On the other hand, when using the general-purpose adhesive shown in the comparative example, in order to make the viscosity range suitable for coating, it was necessary to reduce the non-volatile component to 30% by mass and also the oxygen permeability was high, It did not have a gas barrier function.

The adhesive of the present invention has a strong adhesive force and gas barrier property while achieving a low VOC at the time of laminating. Therefore, it can be used as an adhesive for film laminating that can be used for food packaging materials having excellent environmental compatibility. Is possible. Specific applications include packaging materials for various foods and beverages, as well as fragrances such as foods and teas with various fragrances and oxygen-degrading components, shampoos, rinses, detergents, softeners, soaps, etc. Including sanitary fields, pet food, insect repellents, fragrances, hair dyes, perfumes, pesticides, various organic solvents, etc. . Furthermore, it can also be used as a coating material that can impart gas barrier properties by means such as coating, spraying, dipping, and dripping to a material that is desired to impart gas barrier properties centered on oxygen other than soft packaging materials. For example, it is suitable for use in applications where gas barrier properties such as oxygen are desired, such as adhesives for protective films for solar cells, adhesives for gas barrier substrates for display elements, adhesives for building materials, adhesives for industrial materials, etc. it can.

Claims (24)

A resin composition for an adhesive comprising a polyester polyol (A) having two or more hydroxyl groups and a polyisocyanate (B) having two or more isocyanate groups,
The total solid content of the polyester polyol (A) and the polyisocyanate (B) is an adhesive resin composition characterized by being 50% by mass or more in the total mass of the adhesive resin composition,
The polyester polyol (A) is selected from the group consisting of a polyvalent carboxylic acid component containing at least one of ortho-oriented aromatic dicarboxylic acids or anhydrides, ethylene glycol, propylene glycol, butylene glycol , cyclohexane dimethanol , and glycerin. The resin composition for adhesive agents which is a polyester polyol (A4) obtained by polycondensing the polyhydric alcohol component containing at least 1 sort (s). Ortho-oriented aromatic dicarboxylic acid or its anhydride is orthophthalic acid or its anhydride, naphthalene 2,3-dicarboxylic acid or its anhydride, naphthalene 1,2-dicarboxylic acid or its anhydride, anthraquinone 2,3-dicarboxylic acid 2. The resin composition for an adhesive according to claim 1, which is at least one polyvalent carboxylic acid selected from the group consisting of an anhydride thereof, and 2,3-anthracene dicarboxylic acid or an anhydride thereof, or an anhydride thereof. The resin composition for an adhesive according to claim 1 or 2, wherein the content of the ortho-oriented aromatic dicarboxylic acid or its anhydride is 70 to 100% by mass with respect to all the components of the polyvalent carboxylic acid. The polyester polyol (A1) is a polyester polyol (A1) having at least one carboxy group and two or more hydroxyl groups obtained by reacting a carboxylic acid anhydride or polycarboxylic acid with a polyester polyol having three or more hydroxyl groups. The resin composition for adhesives according to claim 1. The resin composition for an adhesive according to claim 4, wherein the polyester polyol (A1) has a hydroxyl value of 20 to 250 and an acid value of 0 to 200. The resin composition for adhesives according to claim 1, wherein the polyester polyol (A) is a polyester polyol (A2) having a polymerizable carbon-carbon double bond in the molecule. The resin composition for an adhesive according to claim 6, wherein the monomer component having a polymerizable carbon-carbon double bond constituting the polyester polyol (A2) is maleic acid, maleic anhydride, or fumaric acid. The adhesive component according to claim 6 or 7, wherein the monomer component having a polymerizable carbon-carbon double bond is 5 to 60 parts by mass with respect to 100 parts by mass of all monomer components constituting the polyester polyol (A2). Resin composition. The resin composition for an adhesive according to claim 1, wherein the polyester polyol (A) is a polyester polyol (A3) represented by the general formula (1).

(In Formula (1), R < ₁ > -R < ₃ > is respectively independently a hydrogen atom or General formula (2).

(In the formula (2), n represents an integer of 1 to 5, and X represents an optionally substituted 1,2-phenylene group, 1,2-naphthylene group, 2,3-naphthylene group, 2 Represents an arylene group selected from the group consisting of 1,3-anthraquinonediyl group and 2,3-anthracenediyl group, and Y represents an alkylene group having 2 to 6 carbon atoms). However, at least one of R _{1 to} R ₃ represents a group represented by the general formula (2). ) The resin composition for adhesives of Claim 9 which contains 5 mass% or more of glycerol residues of the polyester polyol (A3) represented by the said General formula (1) in a polyester resin composition. The resin composition for adhesives according to claim 1, wherein the polyester polyol (A) is a polyester polyol (A5) having an isocyanuric ring represented by the general formula (3).

(In General Formula (3), R _{1 to} R ₃ are each independently — (CH ₂ ) _n1 —OH (where n1 represents an integer of 2 to 4), or General Formula (4)

(In General Formula (4), n2 represents an integer of 2 to 4, n3 represents an integer of 1 to 5, and X represents a 1,2-phenylene group, a 1,2-naphthylene group, or a 2,3-naphthylene group. , 2,3-anthraquinonediyl group, and 2,3-anthracenediyl group, an arylene group which may have a substituent, and Y represents an alkylene group having 2 to 6 carbon atoms. Represents a group represented by: However, at least one of R ₁ , R ₂ and R ₃ is a group represented by the general formula (4). ) Polyisocyanate (B)
A monomer (C) selected from the group consisting of hexamethylene diisocyanate, isophorone diisocyanate, and metaxylylene diisocyanate,
A polyfunctional polyisocyanate compound (D) selected from the group consisting of isocyanurate, burette and allophanate derived from the monomer (C), or the polyester polyol (A), trimethylolpropane, and glycerin. and bifunctional or polyfunctional polyol compound selected from the group, according to any of the monomer (C) or claim 1-11 polyisocyanates obtainable by reaction of a multifunctional polyisocyanate compound (D) Resin composition for adhesives.
The resin composition for an adhesive according to any one of claims 1 to 12, wherein the polyisocyanate (B) contains a polyisocyanate having an aromatic ring or an aliphatic ring. The resin composition for an adhesive according to claim 13, wherein the polyisocyanate having an aromatic ring is metaxylene diisocyanate or a reaction product of metaxylene diisocyanate and an alcohol having two or more hydroxyl groups. The resin composition for adhesives in any one of Claims 1-14 in which the resin composition for adhesives contains crystalline polyester further. The adhesion according to any one of claims 1 to 15, wherein the adhesive resin composition further comprises a plate-like inorganic compound (E) that is nonionic between layers or non-swellable with respect to water. Agent resin composition. When the total mass of the polyester polyol (A), polyisocyanate (B), and plate-like inorganic compound (E) is 100 parts by mass, the content of the plate-like inorganic compound (E) is 5 to 50 parts by mass. Item 17. A resin composition for an adhesive according to Item 16. The resin composition for adhesives according to claim 16 or 17, wherein the plate-like inorganic compound (E) contains particles having a particle size of 0.1 µm or more. The resin composition for oxygen barrier adhesives in which the resin composition for adhesives in any one of Claims 1-18 has an oxygen barrier property. The resin composition for oxygen barrier adhesives is
When the coating amount of the cured coating film obtained from the polyester polyol (A) and the polyisocyanate (B) is about 5 g / m ² , the oxygen permeability of the cured coating film at 23 ° C. and 90% humidity is 50 cc / m ^2. The resin composition for oxygen barrier adhesives according to claim 19, wherein the resin composition is not more than day · atm. 19. The adhesive resin composition obtained by dissolving a polyester polyol (A) in a ketone solvent, an ester solvent, or a mixed solvent containing a ketone solvent or an ester solvent. A resin composition for an adhesive according to claim 1. The adhesive agent which hardens the resin composition for adhesive agents in any one of Claims 1-18. An oxygen barrier adhesive obtained by curing the resin composition for an oxygen barrier adhesive according to claim 19 or 20. The adhesive according to claim 22 or 23, which is used as an adhesive for film lamination.