JP2013100399A - Anchor coating agent - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an aqueous anchor coating agent having an excellent adhesion to either a polar base material or a nonpolar resin, also having such a level of moist heat resistance that does not cause any deterioration and a decrease in adhesiveness influenced by heat and water (moisture), or the like.SOLUTION: The anchor coating agent is an aqueous resin composition including an aqueous urethane resin (A), an aqueous polyolefin resin (B), an epoxy-based crosslinking agent (C), and an aqueous medium (D), wherein the aqueous urethane resin (A) and the aqueous polyolefin resin (B) have a functional group [X] capable of reacting with an epoxy group, and the anchor coating agent is used for making a laminate.

Description

  The present invention relates to an anchor coating agent useful for various uses including an anchor coating agent for extrusion lamination and a heat sealant.

PET film is widely used for food packaging materials and industrial materials. Similarly, polyolefin (film) typified by polypropylene is also used for general purposes.
In particular, polyolefin may be laminated with other films by extrusion lamination, and an anchor coating agent may be used in combination from the viewpoint of adhesion.
In the fields of food packaging materials and industrial materials, water-based and halogen-free types with low environmental impact are desired. In food packaging materials and industrial materials, high moisture and heat resistance (such as retort) may be required, but there is no extruded anchor coating agent that satisfies the above conditions (aqueous and halogen-free).

  An N, N dialkylallylamine polymer has been proposed as an aqueous anchor coating agent. In this case, the polyethyleneimine system can be diluted with water / alcohol, but has insufficient moisture and heat resistance (see, for example, Patent Document 1).

  In addition, there is an example using an aqueous dispersion of a chlorinated polyolefin resin, but the dispersion is an aqueous type, but contains a large amount of halogen and is not suitable for the purpose of the present invention (see, for example, Patent Document 2 or 3). .

  A dispersion using an acid-modified polyol and an organic polyisocyanate compound has also been proposed. However, in this case, a large amount of an organic solvent is mixed, which is not suitable for the purpose of the present invention (see, for example, Patent Document 4 or 5). .

JP 2000-282005 A JP-A-9-76500 JP 2010-111879 A JP 7-268308 A JP-A-5-263060

  Problems to be solved by the present invention include, for example, excellent adhesion to both polar substrates and nonpolar resins, and deterioration and adhesion due to the influence of heat, water (humidity), etc. It is an object to provide an aqueous anchor coating agent having a level of moisture and heat resistance that does not cause a decrease in the temperature.

  Further, the problem to be solved by the present invention is, for example, excellent adhesion to both a polar base material and a nonpolar resin, and deterioration and adhesion due to the influence of heat, water (humidity), etc. After forming a resin layer by applying a water-based anchor coating agent on the surface of a polar substrate and drying it, it is possible to form a cured resin layer having a level of moisture and heat resistance that does not cause deterioration of It is another object of the present invention to provide an anchor coating agent capable of extruding and laminating a nonpolar resin on the resin layer.

  While the present inventors have studied to solve the above-mentioned problems, the present inventors have studied based on a resin composition in which an aqueous urethane resin (A) and an aqueous polyolefin resin (B) are combined, and can be used in combination with the resin composition. Various combinations with different types of cross-linking agents were studied.

  Specifically, when an epoxy-based cross-linking agent is combined with the resin composition, a resin layer that does not deteriorate unexpectedly due to the influence of heat, water, or the like can be formed without impairing adhesion to the substrate. I found.

  That is, the present invention is an aqueous resin composition containing an aqueous urethane resin (A), an aqueous polyolefin resin (B), an epoxy crosslinking agent (C) and an aqueous medium (D), wherein the aqueous urethane resin (A ) And the aqueous polyolefin resin (B) have a functional group [X] capable of reacting with an epoxy group.

  The anchor coating agent of the present invention has excellent adhesion to substrates and olefin resins made of polyethylene terephthalate and the like widely used in the industry. For example, the anchor coating agent for extrusion lamination Can be used.

  In addition, since the anchor coating agent of the present invention can be suitably used as an anchor coating agent for extrusion lamination, the production efficiency of a laminate (composite member) obtained by laminating various substrates and resins can be remarkably improved. Is possible.

  The anchor coating agent of the present invention is an aqueous resin composition containing an aqueous urethane resin (A), an aqueous polyolefin resin (B), an epoxy-based crosslinking agent (C), an aqueous medium (D), and other additives as necessary. It is essential that the aqueous urethane resin (A) and the aqueous polyolefin resin (B) have a functional group [X] capable of reacting with an epoxy group.

  The anchor coating agent of the present invention uses, as the aqueous urethane resin (A) and the aqueous polyolefin resin (B), those having a functional group [X] capable of undergoing a crosslinking reaction with a functional group possessed by the crosslinking agent, The epoxy crosslinking agent (C) is used.

  The epoxy crosslinking agent (C) can react with the functional group [X] of the aqueous urethane resin (A) and the aqueous polyolefin resin (B) to form a crosslinked structure.

  The epoxy crosslinking agent (C) and the amount used are the epoxy crosslinking agent (C) based on the total amount of the functional group [X] of the aqueous urethane resin (A) and the aqueous polyolefin resin (B). Excellent moisture and heat resistance and excellent adhesion to various substrates when the mass ratio [mass of epoxy group / total amount of functional group [X]] is 5/1 to 1/5. It is preferable to achieve both, and it is more preferable to use in the range of 2/1 to 1/3.

  This makes it possible to form a layer having a strong crosslink density when cured by heating or the like, so that moisture resistance at a level that does not cause deterioration of the layer or decrease in adhesion, regardless of the influence of heat, water (humidity), etc. It becomes possible to achieve both thermal properties and excellent adhesion to various substrates.

  Examples of the functional group [X] include a carboxyl group, a hydroxyl group, and an amino group, and among them, a carboxyl group is preferable.

In addition, in order to make the said water-based urethane resin (A) and the said water-based polyolefin resin (B) exist stably in an aqueous medium (D), the urethane resin and polyolefin which have hydrophilic groups, such as an anionic group and a cationic group, When a resin is used, a carboxyl group or a carboxylate group as the hydrophilic group acts as the functional group [X] during the crosslinking reaction, and a part of the crosslinking agent (C). A crosslinking reaction may occur.
In particular, when a carboxyl group is used as the functional group [X], the aqueous urethane resin (A) preferably has an acid value of 2 to 50, and has an acid value of 5 to 35. It is preferable to use in order to improve adhesion to various substrates.
Moreover, as said aqueous polyolefin resin (B), it is preferable to use what has an acid value of 5-300, and it is more preferable to use what has an acid value of 10-250.

  The water-based urethane resin (A) and the water-based polyolefin resin (B) are preferably dispersed or dissolved independently in the water-based medium (D), but some of them are bonded to form resin particles. Alternatively, so-called core-shell type composite resin particles may be formed.

  Especially, it is preferable that the said water-based urethane resin (A) and the said water-based polyolefin resin (B) form a resin particle each independently, and are disperse | distributed in the said aqueous medium (D).

  The resin particles preferably have an average particle diameter in the range of 10 nm to 500 nm in order to improve the smoothness of the coating film that can be formed. The average particle diameter here refers to the average particle diameter on a volume basis measured by a dynamic light scattering method.

  The aqueous urethane resin (A) may be a mixture of two or more aqueous urethane resins having different compositions. Specifically, two or more aqueous urethane resins having different compositions of the polyol (a1) used for the production of the aqueous urethane resin can be used in combination.

  The mass ratio [(A) / (B)] of the aqueous urethane resin (A) and the aqueous polyolefin resin (B) is preferably in the range of 9/1 to 2/8, and 8/2 to 3 A range of / 7 is preferable for achieving both excellent heat and moisture resistance and excellent adhesion to various substrates.

  In addition, it is preferable that the water-based urethane resin (A) and the water-based polyolefin resin (B) are contained in the range of 5% by mass to 70% by mass with respect to the total amount of the anchor coating agent of the present invention. It is preferable for maintaining stable dispersion stability and coating workability.

  Moreover, the said water-based urethane resin (A) and the said water-based polyolefin resin (B) may have a hydrophilic group from a viewpoint of providing the favorable dispersion stability in the said aqueous medium (D). As the hydrophilic group, for example, an anionic group, a cationic group, and a nonionic group can be used, and it is more preferable to use an anionic group.

  As the anionic group, for example, a carboxyl group, a carboxylate group, a sulfonic acid group, a sulfonate group and the like can be used. Among them, a carboxylate group partially or wholly neutralized with a basic compound or the like It is preferable to use a sulfonate group for producing an aqueous resin having good water dispersibility.

  Moreover, as said cationic group, the thing etc. which neutralized the tertiary amino group or it using the acid compound and the quaternizing agent etc. can be used, for example.

  Examples of the nonionic group include polyoxyalkylene groups such as a polyoxyethylene group, a polyoxypropylene group, a polyoxybutylene group, a poly (oxyethylene-oxypropylene) group, and a polyoxyethylene-polyoxypropylene group. Can be used.

  The aqueous urethane resin (A) has the functional group [X] and can form a cured resin layer having both excellent heat and heat resistance and excellent adhesion to various substrates. Used to obtain

  As the water-based urethane resin (A), it is preferable to use a resin having a weight average molecular weight in the range of 10,000 to 100,000 from the viewpoint of imparting excellent adhesion and durability to polar substrates and nonpolar substrates. It is preferable to use one in the range of 20000 to 50000.

  Moreover, as said aqueous | water-based urethane resin (A), an aromatic ring structure is 200 mmol with respect to the whole aqueous | water-based urethane resin (A) from a viewpoint which raises the adhesiveness with respect to polar base materials with high surface polarity, such as a polyethylene terephthalate, further. / Kg to 9000 mmol / kg is preferably used. More preferably, the range is 350 mmol / kg to 8000 mmol / kg.

  The aqueous urethane resin (A) has the functional group [X] and can form a cured resin layer having both excellent heat and heat resistance and excellent adhesion to various substrates. Used to obtain

  The aqueous urethane resin (A) can be produced, for example, by reacting a polyol (a1), a polyisocyanate (a2), and, if necessary, a chain extender.

  As said polyol (a1), polyester polyol, polycarbonate polyol, polyether polyol, polyolefin polyol etc. can be used individually or in combination of 2 or more, for example.

  Of these, polyester polyols and polycarbonate polyols are preferably used, and aromatic structure-containing polyester polyols and polycarbonate polyols are more preferably used.

  The aromatic structure-containing polyester polyol is preferably used, for example, when it is desired to enhance the adhesion of polyethylene terephthalate to a polar substrate having a high surface polarity. On the other hand, the polycarbonate polyol is preferably used for imparting durability at a level that can prevent deterioration of the substrate and the cured resin layer.

  Examples of the polyester polyol include those obtained by an esterification reaction of a low molecular weight polyol and a polycarboxylic acid, polyesters obtained by a ring-opening polymerization reaction of a cyclic ester compound such as ε-caprolactone, and copolymers of these. Polymerized polyester or the like can be used.

  Examples of the low molecular weight polyol include ethylene glycol, propylene glycol, 1,4-butanediol, 1,6-hexanediol, diethylene glycol, neopentyl glycol, and 1,3-butane having a molecular weight of about 50 to 300. Aliphatic polyols such as diols, aliphatic cyclic structure-containing polyols such as cyclohexanedimethanol, bisphenol compounds such as bisphenol A and bisphenol F, and aromatic structure-containing polyols such as alkylene oxide adducts thereof can be used. .

  Examples of the polycarboxylic acid include aliphatic polycarboxylic acids such as succinic acid, adipic acid, sebacic acid, and dodecanedicarboxylic acid, and aromatic polycarboxylic acids such as terephthalic acid, isophthalic acid, phthalic acid, and naphthalenedicarboxylic acid. , And their anhydrides or ester-forming derivatives can be used.

  An aromatic structure-containing polyester polyol that can be used as the polyester polyol is produced by using, for example, a combination of the low molecular weight polyol and the polycarboxylic acid that has an aromatic structure in one or both of them. Can do.

  Specifically, the aromatic structure-containing polyester polyol includes aliphatic polyols such as ethylene glycol, diethylene glycol, and 1,4-butanediol, and aromatic polycarboxylic acids such as terephthalic acid, isophthalic acid, and phthalic acid. It is preferable to use what is obtained by combining reaction. It can also be produced by reacting an aromatic structure-containing polyol such as bisphenol A with the aliphatic polycarboxylic acid.

  The aromatic structure-containing polyester polyol has an aromatic ring structure in the range of 300 mmol / Kg to 10,000 mmol / Kg with respect to the total amount of the aromatic structure-containing polyester polyol, particularly from the viewpoint of improving adhesion to a polar substrate. It is preferable to use a material having a high surface polarity, such as a polyethylene terephthalate substrate, without impairing the excellent heat and moisture resistance.

  As said polyester polyol, it is preferable to use what has the number average molecular weight of the range of 200-5000. Above all, the aromatic structure-containing polyester polyol has a number average of 250 to 3000 in order to improve adhesion to a polar substrate having a high surface polarity such as a polyethylene terephthalate substrate without impairing excellent heat and moisture resistance. It is preferable to use one having a molecular weight.

  The polyester polyol, preferably the aromatic structure-containing polyester polyol, is 10% by mass to 90% with respect to the total mass of the polyol (a1) and the polyisocyanate (a2) used in the production of the aqueous urethane resin (A) of the present invention. It is preferable to use in the range of mass% in order to improve the adhesion to polar substrates having a high surface polarity such as a polyethylene terephthalate substrate without impairing the excellent heat and moisture resistance.

  Moreover, as a polycarbonate polyol which can be used for the said polyol (a1), what is obtained by making carbonate ester and a polyol react, for example, what is obtained by making phosgene, bisphenol A, etc. react can be used. .

  As the carbonate ester, methyl carbonate, dimethyl carbonate, ethyl carbonate, diethyl carbonate, cyclocarbonate, diphenyl carbonate, or the like can be used.

  Examples of the polyol that can react with the carbonate ester include ethylene glycol, diethylene glycol, 1,2-propylene glycol, dipropylene glycol, 1,4-butanediol, 1,5-pentanediol, and 3-methyl-1,5. -Pentanediol, 1,4-cyclohexanediol, 1,6-hexanediol, cyclohexanedimethanol and other relatively low molecular weight diols having a molecular weight of 50 to 2000, polyethylene glycol, polypropylene glycol, polyhexamethylene adipate, etc. Polyester polyols or the like can be used.

  Among them, it is possible to use a polycarbonate polyol obtained by reacting 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol alone or in combination with two or more carbonates with ethylene-acetic acid. It is preferable for providing adhesion to a nonpolar substrate made of vinyl resin or polypropylene.

  The polycarbonate polyol having a number average molecular weight in the range of 500 to 4000 can be adhered to a nonpolar substrate made of ethylene-vinyl acetate resin, polypropylene, or the like without impairing excellent heat and heat resistance. It is preferable when providing.

  The polycarbonate polyol is used in the range of 10% by mass to 90% by mass with respect to the total mass of the polyol (a1) and the polyisocyanate (a2) used in the production of the aqueous urethane resin (A) of the present invention. It is preferable for imparting adhesion to a nonpolar substrate made of ethylene-vinyl acetate resin, polypropylene, or the like without impairing the excellent heat and moisture resistance.

  Moreover, as said polyether polyol which can be used for the said polyol (a1), the thing which carried out the addition polymerization of the alkylene oxide, for example by using 1 type, or 2 or more types of the compound which has 2 or more of active hydrogen atoms as an initiator is used. can do.

  Examples of the initiator include ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, trimethylene glycol, 1,3-butanediol, 1,4-butanediol, 1,6-hexanediol, bisphenol A, glycerin, and triglyceride. Methylolethane, trimethylolpropane and the like can be used.

  Examples of the alkylene oxide include ethylene oxide, propylene oxide, butylene oxide, styrene oxide, epichlorohydrin, and tetrahydrofuran.

  In addition, as the polyolefin polyol that can be used for the polyol (a1), for example, polyethylene polyol, polypropylene polyol, polyisobutene polyol, hydrogenated (hydrogenated) polybutadiene polyol, and hydrogenated (hydrogenated) polyisoprene polyol are used. Can do.

  Moreover, as said polyol (a1), from a viewpoint of providing favorable water dispersion stability to the said water-based urethane resin (A), it can use combining a hydrophilic group containing polyol other than what was mentioned above.

  As the hydrophilic group-containing polyol, for example, an anionic group-containing polyol other than the above-described polyol, a cationic group-containing polyol, and a nonionic group-containing polyol can be used. Especially, it is preferable to use an anionic group containing polyol or a cationic group containing polyol, and it is more preferable to use an anionic group containing polyol.

  As the anionic group-containing polyol, for example, a carboxyl group-containing polyol or a sulfonic acid group-containing polyol can be used.

  Examples of the carboxyl group-containing polyol include 2,2′-dimethylolpropionic acid, 2,2′-dimethylolbutanoic acid, 2,2′-dimethylolbutyric acid, 2,2′-dimethylolvaleric acid, and the like. Among them, it is preferable to use 2,2′-dimethylolpropionic acid. Moreover, the carboxyl group-containing polyester polyol obtained by making the said carboxyl group-containing polyol and various polycarboxylic acids react can also be used.

  Examples of the sulfonic acid group-containing polyol include dicarboxylic acids such as 5-sulfoisophthalic acid, sulfoterephthalic acid, 4-sulfophthalic acid, and 5 [4-sulfophenoxy] isophthalic acid, and salts thereof, and the aromatic structure-containing polyester. The polyester polyol obtained by making it react with the low molecular weight polyol illustrated as what can be used for manufacture of a polyol (a2) can be used.

  The carboxyl group-containing polyol or sulfonic acid group-containing polyol is preferably used in the range where the acid value of the urethane resin (C) is 10 to 70, more preferably 10 to 50. In addition, the acid value said by this invention is the theoretical value computed based on the usage-amount of acid group containing compounds, such as a carboxyl group containing polyol used for manufacture of the said urethane resin (C).

  The anionic groups are preferably partially or wholly neutralized with a basic compound or the like in order to exhibit good water dispersibility.

  Examples of basic compounds that can be used for neutralizing the anionic group include organic amines having a boiling point of 200 ° C. or higher, such as ammonia, triethylamine, morpholine, monoethanolamine, and diethylethanolamine, NaOH, KOH, and LiOH. A metal hydroxide containing etc. can be used. The basic compound is preferably used in the range of basic compound / anionic group = 0.5 to 3.0 (molar ratio) from the viewpoint of improving the water dispersion stability of the resulting coating agent. It is more preferable to use in the range which becomes 0.9-2.0 (molar ratio).

  Further, as the cationic group-containing polyol, for example, a tertiary amino group-containing polyol can be used. Specifically, N-methyl-diethanolamine, a compound having two epoxies in one molecule, and a secondary amine. A polyol obtained by reacting with can be used.

  It is preferable that a part or all of the cationic group is neutralized with an acidic compound such as formic acid, acetic acid, propionic acid, succinic acid, glutaric acid, tartaric acid and adipic acid.

  Further, the tertiary amino group as the cationic group is preferably partly or entirely quaternized. As the quaternizing agent, for example, dimethyl sulfate, diethyl sulfate, methyl chloride, ethyl chloride and the like can be used, and dimethyl sulfate is preferably used.

  Further, as the nonionic group-containing polyol, polyalkylene glycol having a structural unit derived from ethylene oxide can be used.

  The hydrophilic group-containing polyol is preferably used in the range of 0.3% by mass to 10.0% by mass with respect to the total amount of the polyol (a1) used in the production of the aqueous urethane resin (A).

  Moreover, as said polyol (a1), other polyol can be used as needed besides the above-mentioned polyol.

  Examples of the other polyol include ethylene glycol, diethylene glycol, 1,2-propylene glycol, dipropylene glycol, 1,4-butanediol, 1,5-pentanediol, 3-methyl-1,5-pentanediol, , 4-cyclohexanediol, 1,6-hexanediol, cyclohexanedimethanol and other relatively low molecular weight polyols can be used.

  Examples of the polyisocyanate (a2) capable of reacting with the polyol (a1) include 4,4′-diphenylmethane diisocyanate, 2,4′-diphenylmethane diisocyanate, carbodiimide-modified diphenylmethane diisocyanate, crude diphenylmethane diisocyanate, phenylene diisocyanate, tolylene diisocyanate, Contains aromatic polyisocyanates such as naphthalene diisocyanate, aliphatic polyisocyanates such as hexamethylene diisocyanate, lysine diisocyanate, xylylene diisocyanate, tetramethylxylylene diisocyanate, cycloaliphatic diisocyanate, dicyclohexylmethane diisocyanate, isophorone diisocyanate, etc. Polyisocyanate It is possible to use.

  For example, the aqueous urethane resin (A) is prepared by reacting the polyol (a1) with the polyisocyanate (a2) in the absence of a solvent or in the presence of an organic solvent, and then the urethane. When there is a hydrophilic group in the resin, a neutralized part or all of the hydrophilic group as necessary is mixed with the aqueous medium (D) to make it aqueous. It can be produced by mixing and reacting with a chain extender.

  In the reaction of the polyol (a1) and the polyisocyanate (a2), for example, the equivalent ratio of the isocyanate group of the polyisocyanate (a2) to the hydroxyl group of the polyol (a1) is 0.8 to 2.5. Preferably, it is carried out in the range of 0.9 to 1.5.

  Examples of the organic solvent that can be used for producing the aqueous urethane resin (A) include ketones such as acetone and methyl ethyl ketone; ethers such as tetrahydrofuran and dioxane; acetates such as ethyl acetate and butyl acetate; Nitriles such as acetonitrile; amides such as dimethylformamide and N-methylpyrrolidone can be used alone or in combination of two or more.

  As the aqueous urethane resin (A) used in the present invention, those having a weight average molecular weight in the range of 10,000 to 100,000 can be used. From the viewpoint of improving the adhesion to a polar substrate or a nonpolar substrate, the aqueous urethane resin (A ) May be used to increase the molecular weight.

  As the chain extender that can be used when the aqueous urethane resin (A) is produced, polyamine, other active hydrogen atom-containing compounds, and the like can be used.

  Examples of the polyamine include ethylenediamine, 1,2-propanediamine, 1,6-hexamethylenediamine, piperazine, 2,5-dimethylpiperazine, isophoronediamine, 4,4′-dicyclohexylmethanediamine, and 3,3′-. Diamines such as dimethyl-4,4′-dicyclohexylmethanediamine, 1,4-cyclohexanediamine; N-hydroxymethylaminoethylamine, N-hydroxyethylaminoethylamine, N-hydroxypropylaminopropylamine, N-ethylaminoethylamine, N-methylaminopropylamine; diethylenetriamine, dipropylenetriamine, triethylenetetramine; hydrazine, N, N′-dimethylhydrazine, 1,6-hexamethylenebishydrazine; Razide, adipic acid dihydrazide, glutaric acid dihydrazide, sebacic acid dihydrazide, isophthalic acid dihydrazide; β-semicarbazide propionic acid hydrazide, 3-semicarbazide-propyl-carbazate, semicarbazide-3-semicarbazide methyl-3,5 5-Trimethylcyclohexane can be used, and ethylenediamine is preferably used.

  Examples of the other active hydrogen-containing compound include ethylene glycol, diethylene recall, triethylene glycol, propylene glycol, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, hexamethylene glycol, and sucrose. Glycols such as methylene glycol, glycerin and sorbitol; phenols such as bisphenol A, 4,4′-dihydroxydiphenyl, 4,4′-dihydroxydiphenyl ether, 4,4′-dihydroxydiphenylsulfone, hydrogenated bisphenol A, hydroquinone , And water can be used alone or in combination of two or more thereof within a range in which the storage stability of the coating agent of the present invention is not lowered.

  The chain extender is preferably used, for example, in a range where the equivalent ratio of the amino group and excess isocyanate group of the polyamine is 1.9 or less (equivalent ratio), 0.3 to 1.0 (equivalent It is more preferable to use it in the range of the ratio.

  The aqueous urethane resin (A) produced by the above method can be made aqueous, for example, by the following method.

  [Method 1] After neutralizing or quaternizing some or all of the hydrophilic groups of the aqueous urethane resin obtained by reacting the polyol (a1) with the polyisocyanate (a2), A method in which the aqueous urethane resin (A) is dispersed in water by dispersing and then chain-extending using the chain extender.

  [Method 2] Aqueous urethane resin obtained by reacting polyol (a1) and polyisocyanate (a2) and a chain extender similar to the above are charged in a reaction vessel in a batch or divided, and chain extension is performed. A water-based urethane resin (A) is produced by reacting, and then neutralizing or quaternizing some or all of the hydrophilic groups in the obtained water-based urethane resin (A). How to squeeze

  In [Method 1] to [Method 2], an emulsifier may be used as necessary. In addition, when water is dissolved or dispersed, a machine such as a homogenizer may be used as necessary.

  Examples of the emulsifier include nonionic emulsifiers such as polyoxyethylene nonylphenyl ether, polyoxyethylene lauryl ether, polyoxyethylene styryl phenyl ether, polyoxyethylene sorbitol tetraoleate, and polyoxyethylene / polyoxypropylene copolymer. Fatty acid salts such as sodium oleate, alkyl sulfates, alkylbenzene sulfonates, alkyl sulfosuccinates, naphthalene sulfonates, polyoxyethylene alkyl sulfates, alkane sulfonate sodium salts, sodium alkyl diphenyl ether sulfonates, etc. Anionic emulsifiers; Cationic emulsifiers such as alkylamine salts, alkyltrimethylammonium salts, and alkyldimethylbenzylammonium salts. It is. Among these, from the viewpoint of maintaining the excellent storage stability of the coating agent of the present invention, it is basically preferable to use an anionic or nonionic emulsifier.

  The aqueous urethane resin (A) aqueous dispersion in which the aqueous urethane resin (A) obtained by the above method is dispersed in the aqueous medium (D) is obtained by adding the aqueous urethane resin (A) to the total amount of the aqueous dispersion. The anchor coating agent that improves the ease of preparation of the anchor coating agent of the present invention and has both excellent heat and moisture resistance and excellent adhesion to various substrates. It is preferable when preparing.

  Next, the aqueous polyolefin resin (B) used for production of the anchor coating agent of the present invention will be described.

  Examples of the aqueous polyolefin resin (B) used in the present invention include homopolymers and copolymers such as ethylene, propylene, 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene and 1-nonene. Among them, those having a functional group [X] can be used, specifically, polyethylene, polypropylene, polybutadiene, ethylene-propylene copolymer, natural rubber, synthetic isopropylene rubber, ethylene-vinyl acetate copolymer. Among them, it is essential to use those having a functional group [X] capable of reacting with the epoxy group or isocyanate group of the crosslinking agent (C). When the aqueous polyolefin resin (B) is a copolymer, it may be a random copolymer or a block copolymer.

  Examples of the functional group [X] of the aqueous polyolefin resin (B) include a carboxyl group and the like, as in the functional group [X] of the aqueous urethane resin (A). preferable. The functional group [X] may be the same functional group as the hydrophilic group of the aqueous polyolefin resin (B). Specifically, when a carboxyl group or a carboxylate group which is an anionic group is used as the hydrophilic group, the carboxyl group or the like may act as the functional group [X] during the crosslinking reaction.

  Examples of the aqueous polyolefin resin (B) having a carboxyl group as the functional group [X] include those obtained by reacting the polyolefin resin exemplified above with an unsaturated carboxylic acid, and reacting with a vinyl monomer. It is preferable to use so-called modified polyolefin resins such as those obtained or chlorinated.

  For example, a carboxyl group as the functional group [X] can be introduced into the aqueous polyolefin resin (B) by reacting the polyolefin resin with an unsaturated dicarboxylic acid such as maleic anhydride.

  Examples of the unsaturated dicarboxylic acid include maleic acid, fumaric acid, itaconic acid, citraconic acid, and anhydrides thereof, and unsaturated dicarboxylic acid esters (butyl maleate, dibutyl maleate, butyl itaconate, etc.). One or more of these can be used. Of these, maleic anhydride is preferred.

  The aqueous polyolefin resin (B) modified with the unsaturated carboxylic acid has an acid value in the range of 5 to 250 to prevent deterioration of the cured resin layer due to the influence of heat, water (humidity) or the like. And it is preferable when preventing the fall of the adhesiveness with respect to various base materials.

  The modification of the polyolefin resin can be performed, for example, by reacting the polyolefin resin as described above with an unsaturated dicarboxylic acid such as maleic acid or the like.

  Moreover, as said water-based polyolefin resin (B), in order to prevent deterioration of the resin cured layer by influence of heat, water (humidity), etc., and to prevent the adhesiveness fall with respect to various base materials, the weight average of 20000-500000 It is preferable to use one having a molecular weight. In addition, the said weight average molecular weight points out the value measured using gel permeation chromatography (GPC).

Next, the epoxy crosslinking agent (C) used in the present invention will be described.
In the present invention, the use of the epoxy-based crosslinking agent (C) is important in obtaining an anchor coating agent that achieves both excellent heat and heat resistance and excellent adhesion to various substrates. Use in combination with the epoxy-based crosslinking agent (C) is more preferable for preventing deterioration of the cured resin layer due to the influence of heat, water (humidity) and the like, and preventing deterioration of adhesion to various substrates.

  Examples of the epoxy crosslinking agent (C) include bisphenol A epichlorohydrin type epoxy resin, ethylene glycidyl ether, polyethylene glycol diglycidyl ether, glycerin diglycidyl ether, glycerin triglycidyl ether, 1,6-hexanediol glycidyl ether, Trimethylolpropane triglycidyl ether, diglycidyl aniline, diamine glycidyl amine, N, N, N ′, N′-tetraglycidyl-m-xylylenediamine, 1,3-bis (N, N′-diamine glycidylaminomethyl) Cyclohexane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-glycidoxypropylmethyldimethyl Use hydrolyzable silyl group-containing epoxy-based crosslinking agent (c1-1) such as xylsilane, 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltriethoxysilane can do.

  Among them, the use of the hydrolyzable silyl group-containing epoxy-based crosslinking agent (c1-1) prevents deterioration of the cured resin layer due to the influence of heat, water (humidity), etc. More preferable for preventing the decrease, 3-glycidoxypropyltriethoxysilane, 3-glycidoxypropyltrimethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane and 2- (3,4) It is more preferable to use one or more selected from the group consisting of -epoxycyclohexyl) ethyltriethoxysilane.

Next, the aqueous medium (D) used in the present invention will be described.
Examples of the aqueous medium (D) used in the present invention include water, an organic solvent miscible with water, and a mixture thereof. Examples of the organic solvent miscible with water include alcohols such as methanol, ethanol, n- and isopropanol; ketones such as acetone and methyl ethyl ketone; polyalkylene glycols such as ethylene glycol, diethylene glycol and propylene glycol; Alkyl ethers; lactams such as N-methyl-2-pyrrolidone, and the like. In the present invention, only water may be used, a mixture of water and an organic solvent miscible with water may be used, or only an organic solvent miscible with water may be used. From the viewpoint of safety and load on the environment, water alone or a mixture of water and an organic solvent miscible with water is preferable, and only water is particularly preferable.

  The aqueous medium (D) is contained in the range of 30% by mass to 90% by mass with respect to the total amount of the anchor coating agent of the present invention, which improves the workability of the anchor coating agent of the present invention. , It is preferable for achieving both adhesion and heat-and-moisture resistance.

  The anchor coating agent of the present invention comprises, for example, an aqueous dispersion of the aqueous urethane resin (A) obtained by the above method, an aqueous dispersion of the aqueous polyolefin resin (B), and the epoxy crosslinking agent (C). It can be manufactured by supplying and mixing all at once or divided. The crosslinking agent (C) may be mixed with an aqueous dispersion of the aqueous urethane resin (A) or an aqueous dispersion of the aqueous polyolefin resin (B).

  The anchor coating agent of the present invention obtained by the above method may contain other additives as required in addition to the above-described components.

  Examples of the additive include an antioxidant, a light-resistant agent, a plasticizer, a film-forming aid, a leveling agent, a foaming agent, a thickener, a colorant, a flame retardant, other aqueous resins, and various fillers. It can be used within a range that does not impair the effect.

  As the additive, for example, a surfactant can be used from the viewpoint of further improving the dispersion stability of the anchor coating agent of the present invention. However, since the surfactant may reduce the adhesion and water resistance of the resulting coating, 20 parts by mass with respect to a total of 100 parts by mass of the aqueous urethane resin (A) and the aqueous polyolefin resin (B). It is preferable to use in the following ranges, and it is preferable not to use as much as possible.

  Since the anchor coating agent of the present invention can form a cured product layer having excellent adhesion to a substrate and excellent heat and moisture resistance, it is used for coating agents, adhesives, heat sealants and the like that coat the surface of various substrates. be able to. In particular, since the anchor coating agent of the present invention has excellent adhesion to both polar substrates and nonpolar substrates, in addition to the anchor coating agent for extrusion lamination of polar substrates and nonpolar resins. Can also be suitably used for adhesives and heat sealants between polar and nonpolar substrates.

  Examples of the substrate capable of forming a film or an adhesive layer using the coating agent, adhesive, or heat sealant of the present invention include various plastics and films thereof, metal, glass, paper, and wood. Specifically, a polyethylene terephthalate base material etc. are mentioned as a polar base material. Moreover, as a nonpolar resin and a nonpolar base material, ethylene-vinyl acetate resin, polyethylene, a polypropylene etc. are mentioned, for example.

  Examples of the method for applying the anchor coating agent of the present invention to the substrate surface include a spray method, a curtain coater method, a flow coater method, a roll coater method, a brush coating method, and a dipping method.

  Hereinafter, the present invention will be specifically described with reference to Examples and Comparative Examples.

<Preparation of aqueous urethane resin>
[Preparation Example 1]
While introducing nitrogen gas in a reactor equipped with a thermometer, a nitrogen gas inlet tube, and a stirrer, 830 parts by mass of terephthalic acid, 830 parts by mass of isophthalic acid, 374 parts by mass of ethylene glycol, 604 parts by mass of neopentyl glycol and dibutyltin After 0.5 parts by mass of oxide was charged and esterified at 180 to 230 ° C. for 5 hours, a polycondensation reaction was carried out at 260 ° C. for 6 hours until the acid value was less than 1, whereby an acid value of 0.2 and a hydroxyl value of 74. 5 polyester polyol A was obtained.

  After dehydrating 1000 parts by weight of the polyester polyol A at 100 ° C. under reduced pressure, cooling to 80 ° C., adding 690 parts by weight of methyl ethyl ketone, sufficiently stirring and dissolving, adding 77 parts by weight of 2,2′-dimethylolpropionic acid, Further, 209 parts by mass of hexamethylene diisocyanate was added and reacted at 75 ° C. for 8 hours.

  After confirming that the mass ratio of unreacted isocyanate groups remaining in the reaction mixture became 0.1 mass% or less, the mixture was cooled to 50 ° C., 58 parts by mass of triethylamine and 5100 parts by mass of water were added, and the pressure was reduced. Then, methyl ethyl ketone was removed at a temperature of 40 to 60 ° C., and the concentration was adjusted by adding water to obtain a composition (I) having a nonvolatile content of 20 mass% in which an aqueous urethane resin was dispersed in water.

[Preparation Example 2]
While introducing nitrogen gas in a reactor equipped with a thermometer, a nitrogen gas inlet tube, and a stirrer, 1000 parts by mass of modified polyolefin (Porestar VS-1236 made by Starlight PMC) was added, and stirred and melted at 80 ° C. for 3 hours. Next, the mixture was cooled to 50 ° C., neutralized by adding 180 parts by mass of triethylamine, and then water-solubilized by adding 2153 parts by mass of water to obtain a composition (III) having a nonvolatile content of 30% by mass.

Examples 1-3
The following raw materials were mixed with a preparation solution as shown in Table 1, a coating film was formed on the polyester film under the following coating conditions, and then laminated.
Aqueous urethane resin: Resin produced in Preparation Example 1 Aqueous olefin resin: Resin produced in Preparation Example 2
Epoxy crosslinking agent: Watersol WSA-950 (NV100%), manufactured by DIC Corporation
PET film: E5100 50μ (Toyobo)

Coating conditions Apply the adjustment liquid with bar coater # 4 and dry at 100 ° C for 30 seconds.

Extrusion laminating test The corona-treated surface of Tosero TUX-HC-60 (manufactured by Tosero) and the above coated surface were combined and laminated with a heat sealer (210 ° C., 0.1 MPa, 10 seconds).

  Moisture and heat resistance test conditions: 105 ° C, 100%, 24 hours (pressure cooker)

Comparative Examples 1 and 2
Evaluation was performed in the same manner as in Example 1 except that 100 parts of each of the aqueous urethane resin and the aqueous polyolefin resin were used alone.
Comparative Example 3
Evaluation was performed in the same manner as in Example 1 except that 60.0 parts of an aqueous urethane resin and 40.0 parts of an aqueous polyolefin resin were blended and no epoxy crosslinking agent was used.

Claims (8)

An aqueous resin composition comprising an aqueous urethane resin (A), an aqueous polyolefin resin (B), an epoxy crosslinking agent (C) and an aqueous medium (D), wherein the aqueous urethane resin (A) and the aqueous polyolefin resin ( An anchor coating agent, wherein B) has a functional group [X] capable of reacting with an epoxy group. Ratio of epoxy group mass of epoxy crosslinking agent (C) to total amount of functional group [X] of water-based urethane resin (A) and water-based polyolefin resin (B) [total material of epoxy groups The anchor coating agent according to claim 1, wherein the amount / the total amount of the functional group [X] is 5/1 to 1/5. The anchor coating agent according to claim 1, wherein the epoxy crosslinking agent (C) is a hydrolyzable silyl group-containing epoxy crosslinking agent (c1-1). The anchor coating agent according to claim 1, wherein the aqueous urethane resin (A) has at least one selected from the group consisting of a carboxyl group, a carboxylate group, a sulfonic acid group, and a sulfonate group as a hydrophilic group. . The water-based urethane resin (A) includes a polyol (a1) containing at least one selected from the group consisting of an aromatic ring structure-containing polyester polyol and a polycarbonate polyol, and an aromatic ring structure or an aliphatic cyclic structure-containing polyisocyanate. The anchor coating agent according to claim 1, which is obtained by reacting the polyisocyanate (a2) to be contained. The resin layer formed by apply | coating the anchor coating agent as described in any one of Claims 1-5 to the surface of a polar base material and drying is provided, and a nonpolar resin is extruded and laminated on the resin layer. A laminate characterized by the above. A cured resin layer formed by applying and drying the anchor coating agent according to any one of claims 1 to 5 is provided on the surface of the polar substrate (I), and the surface of the cured resin layer is nonpolar. The laminated body obtained by mounting base material (II) and then heating at 80 to 180 degreeC. The laminate according to claim 7, wherein the polar substrate is a polyethylene terephthalate substrate, and the nonpolar resin is an olefin resin.