KR100586135B1 - Polyisocyanate curing agents for laminate adhesive, laminate adhesive containing the same, and its use for film lamination - Google Patents

Abstract

The present invention relates to a polyisocyanate curing agent for a laminate adhesive having excellent heat resistance, durability, and adhesion to a metal-based film and a polyolefin film, a laminate adhesive containing the curing agent, and a method for use in film lamination of the adhesive. To provide. The present invention provides a polyisocyanate curing agent for a laminate adhesive containing a polyisocyanate having a hydrophilic polar group, a laminate adhesive containing the polyisocyanate curing agent and an active hydrogen compound, and a method for use in film lamination of the adhesive.

Description

Polyisocyanate curing agents for laminate adhesive, laminate adhesive containing the same, and its use for film lamination}             

The present invention relates to a polyisocyanate curing agent for a laminate adhesive having a hydrophilic polar group, a laminate adhesive containing the curing agent and a method for use in film lamination of the adhesive.

In recent years, as a packaging method, a composite flexible packaging has developed remarkably due to the strength of packaging, product protection, workability in packaging, propagation effect of packaging, reduction of packaging price due to mass supply and cheap supply of film, and the like.

Adhesives used for film lamination in such composite flexible packaging include resins (subjects) and poly-containing active hydrogen groups such as hydroxyl groups, which can be widely applied to various films because of excellent adhesion performance, durability and heat resistance. Two-component curable polyurethane adhesives composed of isocyanates (curing agents) have become mainstream.

For example, Japanese Patent Laid-Open No. 93-112766 discloses an adhesive using a polyurethane resin and a polyisocyanate curing agent, and an adhesive having a hydrophilic polar group introduced into the polyurethane resin. In addition, Japanese Patent Laid-Open No. 95-48429 discloses a polyisocyanate curing agent having a hydrophilic polar group introduced into a polyisocyanate.

However, when the polyisocyanate curing agent described in Japanese Patent Laid-Open No. 93-112766 uses a resin other than a polyurethane-based resin as a subject, adhesiveness with a metal foil, a metal vapor deposition film, and a polyolefin film becomes insufficient. Japanese Patent Laid-Open Publication No. 95-48429 also describes a water-based adhesive, but the water-based adhesive requires a lot of energy to scatter water.

The present invention seeks to provide a polyisocyanate curing agent for a laminate adhesive having excellent heat resistance, durability, and adhesion between a metal film and a polyolefin film, a laminate adhesive containing the curing agent, and a method of using the adhesive in film lamination.

That is, the present invention relates to a curing agent, an adhesive according to the following (1) to (3), and a method of use in lamination of the adhesive:

(1) a polyisocyanate curing agent for a non-aqueous laminate adhesive comprising a polyisocyanate having a hydrophilic polar group;

(2) a non-aqueous laminate adhesive comprising a polyisocyanate curing agent according to (1) and an active hydrogen compound;

(3) A method for use in film lamination of an adhesive containing a polyisocyanate curing agent according to (1) and an active hydrogen compound.

The polyisocyanate curing agent for the laminate adhesive of the present invention contains a polyisocyanate containing a hydrophilic polar group.

The polyisocyanate having a hydrophilic polar group can be easily obtained by reacting an organic polyisocyanate with a hydrophilic polar group-containing compound containing at least one active hydrogen group.

As organic polyisocyanate, well-known organic polyisocyanate and its modified body are mentioned.

Specific examples include 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, xylylene-1,4-diisocyanate, xylylene-1,3-diisocyanate, xylylene-1,2- Diisocyanate, 4,4'-diphenylmethane diisocyanate, 2,4'-diphenylmethane diisocyanate, 4,4'-diphenylether diisocyanate, 2-nitrodiphenyl-4,4'-diisocyanate, 2,2'-diphenylpropane-4,4'-diisocyanate, 3,3'-dimethyldiphenylmethane-4,4'-diisocyanate, 4,4'-diphenylpropanediisocyanate, m-phenylenedi Isocyanate, p-phenylene diisocyanate, naphthylene-1,4-diisocyanate, naphthylene-1,5-diisocyanate, 3,3'-dimethoxydiphenyl-4,4'-diisocyanate, tetramethylxylyl Aromatic diisocyanates such as rendiisocyanate; Aliphatic diisocyanates such as tetramethylene diisocyanate, hexamethylene diisocyanate, 3-methyl-1,5-pentane diisocyanate, and ridine diisocyanate; Alicyclic diisocyanates such as isophorone diisocyanate, hydrogenated tolylene diisocyanate, hydrogenated xylene diisocyanate, hydrogenated diphenylmethane diisocyanate; Polymers of adducts, biuret, carbodiimide, uretonimine, uretodione, isocyanurate and isocyanurate modifications thereof; And mixtures of two or more of them.

Among these, the isocyanurate modified body and the isocyanurate-uretodione modified body of hexamethylene diisocyanate which are excellent in durability, heat resistance, etc. are preferable.

Examples of the hydrophilic polar group in the hydrophilic polar group-containing compound having an active hydrogen group include nonionic polar groups, anionic polar groups, cationic polar groups and amphoteric polar groups. In the present invention, these hydrophilic polar groups may be used alone or in combination with different kinds of hydrophilic polar groups. In view of the stability of the obtained polyisocyanate curing agent for the laminate adhesive, a nonionic polar group is preferable as the hydrophilic polar group of the polyisocyanate curing agent of the present invention.

As a nonionic polar group containing compound which has an active hydrogen group, poly (oxyalkylene) ether monool whose ethylene oxide unit is 50 mol% or more, and whose repeating number is preferably 3 to 90, more preferably 5 to 50. , Poly (oxyalkylene) ether polyol, poly (oxyalkylene) fatty acid ester monool, and the like. In this invention, poly (oxyalkylene) ether monool and poly (oxyalkylene) ether polyol are preferable, and poly (oxyalkylene) ether monool is more preferable.

As an initiator used in the production of the poly (oxyalkylene) ethermonol, methanol, ethanol, n-propanol, i-propanol, n-butanol, i-butanol, t-butanol, cyclohexanol, phenyl and the like Can be mentioned. As an initiator used for manufacture of a poly (oxyalkylene) ether polyol, ethylene glycol, propylene glycol, anilene, trimethylol propane, glycerin, etc. are mentioned. Among these, compounds having 5 or less carbon atoms, such as methanol, ethanol, ethylene glycol, and propylene glycol, are preferred because of good adhesion to metals, and methanol, ethanol and the like, which are monools having 5 or less carbon atoms, are more preferable.

In addition, as a fatty acid used for manufacture of the said poly (oxyalkylene) fatty acid ester monool, acetic acid, propionic acid, n-butyric acid, i-butyric acid, n- valeric acid, i- valeric acid, capronic acid, glycolic acid, Lactic acid, methoxyacetic acid, and the like. Among these fatty acids, compounds such as acetic acid, propionic acid, n-butyric acid, i-butyric acid, n-valeric acid and i-valeric acid having 5 or less carbon atoms are preferred because of good adhesion to metals.

Suitable examples of cationic polar group-containing compounds having an active hydrogen group are those prepared from organic acids and neutralizing agents having at least one active hydrogen group. Examples of the organic acid include a compound having a carboxyl group, sulfonic acid group, phosphoric acid group, phosphonic acid group, phosphinic acid group, thiosulfonic acid group, and the like, which organic acid group may be introduced on its own (independently) or provided as a chelating compound. It may be.

Specific examples of the organic acid having one or more active hydrogen groups include α-hydroxypropionic acid, hydroxysuccinic acid, dihydroxysuccinic acid, ε-hydroxypropane-1,2,3-tricarboxylic acid, hydroxyacetic acid, α- Hydroxy fatty acids which hydroxyated hydroxybutyric acid, hydroxystearic acid, and unsaturated fatty acids (for example, ricinoleic acid, ricinoelic acid, ricinostearic acid, salicylic acid, mandelic acid, oleic acid, linoleic acid); Diamine type amino acids such as glutamine, asparagine, lidine, diaminopropionic acid, ornithine and diaminobenzoic acid; Monoamine amino acids such as glycine, alanine, glutamic acid, taurine, aminocaproic acid, aminobenzoic acid and aminoisophthalic acid; Aminosulfonic acids such as sulfamic acid and diaminobenzenesulfonic acid; Carboxyl group-containing polyols such as 2,2-dimethylolpropionic acid, 2,2-dimethylolbutyric acid and 2,2-dimethylolvaleric acid; Chelate-like compounds such as adducts of iminodiacetic acid and glycidyl; Polyester polyols prepared using 5-sodium sulfoisophthalic acid and 5-potassium sulfoisophthalic acid; Polycaprolactone prepared using water and a carboxyl group-containing alcohol as an initiator; And transesterification of an active hydrogen group-containing polyester or an active hydrogen group-containing polycarbonate with a carboxyl group-containing alcohol.

In addition, half-chain mixtures having a carboxyl group and half-amide mixtures obtained by reacting long chain polyols, the aforementioned low molecular polyols with low molecular polyamines, and polycarboxylic acid anhydrides can also be used. In particular, when a polyol is added to an acid anhydride such as pyromellitic anhydride, two carbon acids are generated, and thus anionic polar groups can be introduced into the molecular chain of the polyester polyol. Phosphoric acid etc. are mentioned as another anionic polar group other than the anionic polar group mentioned above. Specifically, the long chain polyol is the aforementioned polyester polyol, polyether polyol, polycarbonate polyol, polyolefin polyol and the like.

As a neutralizing agent, ammonia, ethylamine, trimethylamine, triethylamine, triisopropylamine, tributylamine, triethanolamine, N-methyl diethanolamine, N-phenyl diethanolamine, monoethanolamine, dimethylethanolamine, Organic amines such as diethylethanolamine, morpholine, N-methylmorpholine and 2-amino-2-ethyl-1-propanol; Alkali metals such as lithium, potassium and sodium; Although inorganic alkalis, such as sodium hydroxide and potassium hydroxide, etc. are mentioned, In order to improve weather resistance and water resistance after drying, ammonia, trimethylamine, or triethylamine which dissociates easily by heat and is highly volatile is preferable.

These organic acids and neutralizing agents can be used individually or in mixture of 2 or more types, respectively.

Suitable examples of the cationic polar group-containing compound having an active hydrogen group include a tertiary amine having at least one active hydrogen group, and a neutralizing or quaternizing agent composed of an inorganic acid and an organic acid.

As the tertiary amine having one or more active hydrogen groups, N, N-dimethylethanolamine, N, N-diethylethanolamine, N, N-dipropylethanolamine, N, N-diphenylethanolamine, N -Methyl-N-ethylethanolamine, N-methyl-N-phenylethanolamine, N, N-dimethylpropanolamine, N-methyl-N-ethylpropanolamine, N-methyldiethanolamine, N-ethyldiethanolamine , N-methyldipropanolamine, N-phenyldiethanolamine, N-phenyldipropanolamine, N-hydroxyethyl-N-hydroxypropyl-methylamine, N, N'-dihydroxyethylpiperidine, Triethanolamine, trisisopropanolamine, N-methyl-bis- (3-aminopropyl) -amine, N-methyl-bis- (2-aminopropyl) -amine, etc. are mentioned. Moreover, what added alkylene oxide to primary amines, such as ammonia and methylamine, and secondary amines, such as dimethylamine, can also be used.

Examples of the inorganic acid and organic acid include hydrochloric acid, acetic acid, lactic acid, cyanoacetic acid, phosphoric acid, sulfuric acid, and the like. Examples of the quaternizing agent include dimethyl sulfate, benzyl chloride, bromoacetamide, chloroacetamide, alkyl halides (for example, ethyl bromide, propyl bromide, and butyl bromide).

As a cationic polar group containing compound other than the compound mentioned above, a primary amine salt, a secondary amine salt, a tertiary amine salt, a pyridinium salt, etc. are mentioned.

As a positive polar group containing compound which has an active hydrogen group, the compound which has a positive polar group, such as a sulfobetaine group produced | generated by reacting a tertiary amino group containing polyol and a sultone, is mentioned.

The addition and reaction time of the neutralizing agent and the quaternizing agent in the anionic and cationic polar groups may be after the reaction of the organic polyisocyanate with an organic acid and / or tertiary amine having an active hydrogen group, and an organic acid having an active hydrogen group and / or After reacting the tertiary amine with the neutralizing and quaternizing agents, the reactant and the organic polyisocyanate can be reacted. In the case of a sulfonic acid group containing compound, it is preferable to neutralize before making it react with organic polyisocyanate.

In the polyisocyanate curing agent for the laminate adhesive of the present invention, the amount of the hydrophilic polar group introduced is as follows.

In the case of introducing a nonionic polar group, the content of ethylene oxide units is preferably 0.1 to 40% by weight, particularly 0.5 to 30% by weight, in terms of solid content relative to the polyisocyanate curing agent.

In the case of introducing anionic and cationic polar groups, the polar group is preferably 0.1 to 3.0 mmol / g, especially 0.15 to 2.9 mmol / g.

When the introduction amount of the hydrophilic polar group is less than the lower limit, the adhesiveness on the metal is likely to be insufficient. On the contrary, when the upper limit is exceeded, durability of the adhesive, particularly water resistance, tends to be insufficient.

In this invention, the hardening | curing agent for laminate adhesives can also be made to further react with the hydrophobic group containing compound which has an active hydrogen group as needed. As a hydrophobic group containing compound which has this active hydrogen group, methanol, ethanol, n-propanol, i-propanol, n-butanol, i-butanol, t-butanol, pentanol, hexanol, heptanol, octanol, 2-ethyl Low molecular monools such as hexanol, benzyl alcohol, cyclohexanol, alkylene glycol monoalkyl ether; Low molecular weight primary monoamines such as ethylamine, butylamine and aniline; Low molecular weight secondary monoamines such as diethylamine, dibutylamine and methylaniline; Active hydrogen group-containing polyesters; Active hydrogen group-containing polyethers having less than 50 mol% ethylene oxide units; Active hydrogen group-containing polycarbonates; Active hydrogen group-containing polyolefins; And esters of hydroxy higher fatty acids and hydroxy higher fatty acids having 6 or more carbon atoms.

In the reaction of the organic polyisocyanate with the active hydrogen group-containing compound, the reaction temperature is preferably 10 to 120 ° C, particularly 30 to 100 ° C. In addition, a hydrophobic group-containing compound having an active hydrogen group, which may be used as necessary, may be added at the same time or at another time of introduction of the hydrophilic polar group. In this case, a urethanation catalyst, such as dibutyltin dilaurate and triethylenediamine, can be added as needed.

The isocyanate group content of the polyisocyanate curing agent for the laminate adhesive thus obtained is preferably 5 to 50% by weight, particularly 10 to 40% by weight.

In the present invention, the average number of functional groups of the polyisocyanate curing agent for the laminate adhesive is preferably 2.0 to 5.0, particularly 2.0 to 4.0. If the average number of functional groups is less than 2.0, the crosslinking density becomes small and the adhesive strength tends to be insufficient. Moreover, when it exceeds 5.0, the crosslinking density of hardened | cured material will become large unnecessarily and the flexibility of an adhesive layer will become inadequate easily.

In the laminate adhesive of the present invention, the active hydrogen compound, which is a subject to be used in combination with a polyisocyanate curing agent, preferably contains at least one active hydrogen group in a molecule, and has a number average molecular weight of 500 to 100,000, especially a polymer activity of 1,000 to 80,000. Hydrogen compounds are preferred. For example, polyurethane-based resin, polyester-based resin, polyamide-based resin, acrylic-based resin, coumarone-based resin, melamine-based resin, urea-based resin, rodin-based resin, epoxy resin, Cellulose resins such as phenol resins, vinyl acetate-based resins and cellulose; natural resins such as starch and glue; and polyvinyl alcohols. Among them, polyurethane-based resins are preferable in consideration of adhesion, durability and the like in the base material.

The said polyurethane resin contains the polyurethane urea resin etc. which have a urethane bond and a urea bond other than the polyurethane resin which has a urethane bond.

In the molecule | numerator of a polyurethane-type resin, 1 or more, Preferably 2 or more active hydrogen groups (for example, hydroxyl group) are contained. A polyisocyanate curing agent for a laminate adhesive having a hydrophilic polar group is added to such a polyurethane-based resin and used as a two-component curable laminate adhesive.

A polyurethane resin is obtained by making an active hydrogen containing compound and organic polyisocyanate react by a well-known method.

The said active hydrogen group containing compound is what is called a long chain polyol and / or a chain extending agent. In the polyurethane-based resin of the present invention, it is preferable to contain 50 to 90% by weight of the long chain polyol.

Examples of the long-chain polyols include polyester polyols, polycarbonate polyols, polyether polyols, polyolefin polyols, animal and vegetable polyols, and copolyols thereof. These long chain polyols may be used alone or in combination of two or more thereof. The number average molecular weight of these long chain polyols is preferably 500 to 10,000. In the present invention, polyester polyol is preferable in consideration of adhesion, durability and the like.

As said polyester polyol, well-known succinic acid, adipic acid, sebacic acid, azelaic acid, terephthalic acid, isophthalic acid, orthophthalic acid, hexahydro terephthalic acid, hexahydroisophthalic acid, hexahydroorthophthalic acid, naphthalenedicarboxylic acid, trimellitic acid Polycarboxylic acids such as; Acid esters; Or at least one selected from acid anhydrides, ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,3-butanediol, 1,4-butanediol, 1,5-pentanediol, 1,6- Hexanediol, 3-methyl-1,5-pentanediol, neopentylglycol, 1,8-octanediol, 1,9-nonanediol, diethylene glycol, dipropylene glycol, 1,4-cyclohexanedimethanol; Ethylene oxide or propylene oxide adducts of bisphenol A; Low molecular polyols such as glycerin, trimethylolpropane and pentaerythritol; Low molecular polyamines such as hexamethylenediamine, xylenediamine and isophoronediamine; Polyester polyol or polyesteramide polyol obtained by dehydrating condensation reaction of 1 or more types chosen from low molecular weight amino alcohols, such as a monoethanolamine and a diethanolamine, is mentioned. In the low molecular polyols, low molecular polyamines and low molecular amino alcohols of the present invention, the term "low molecular weight" means that the number average molecular weight is less than 500.

Moreover, as an initiator of the said low molecular weight polyol, the lactone-type polyester polyol obtained by the ring-opening polymerization reaction of cyclic ester (lactone) monomer (for example, (epsilon) -caprolactone, (gamma) -valerolactone) is mentioned.

Examples of the polycarbonate polyol include those obtained by dealcoholization and dephenol reaction of the above low molecular weight polyol with diethylene carbonate, dimethyl carbonate, diethyl carbonate and diphenyl carbonate.

Examples of the polyether polyols include polyethylene glycol, polypropylene glycol, polytetramethylene ether glycol, and polyether polyols copolymerized with ethylene oxide, propylene oxide, tetrahydrofuran, and the like, and the aforementioned polyesters. And polyester ether polyols using polyols and polycarbonate polyols as initiators.

Examples of the polyolefin polyols include hydroxyl group-containing polybutadiene, hydrogenated hydroxyl group-containing polybutadiene, hydroxyl group-containing polyisoprene, hydrogenated hydroxyl group-containing polyisoprene, hydroxyl group-containing chlorinated polypropylene, and hydroxyl group-containing chlorinated polyethylene.

Examples of animal and vegetable oil-based polyols include castor oil-based polyols and silk fibroin.

In addition, if it has two or more active hydrogen groups other than a dimer acid polyol and a hydrogenated dimer acid polyol, polyester resin, polyamide resin, acrylic resin, coumarone resin, melamine resin, urea resin, rodin Fibrous resins such as resins, epoxy resins, phenol resins, cellulose, natural resins such as starch and glue, and resins such as polyvinyl alcohol can also be suitably used as long-chain polyols. The number average molecular weight of these resins is preferably 500 to 10,000.

The chain extender is generally a low molecular compound containing two or more active hydrogen groups in a molecule, and examples thereof include low molecular polyols, low molecular polyamines, low molecular amino alcohols, and the like, which may be used alone or in combination of two or more thereof. .

As organic polyisocyanate, the organic diisocyanate used for manufacture of the hardening | curing agent for laminate adhesives mentioned above, its modified body, etc. are mentioned.

In synthesizing the polyurethane-based resin, the molar ratio of the isocyanate group / active hydrogen group in the active hydrogen group-containing compound and the organic polyisocyanate is preferably from 0.6 / 1 to 1 / 0.6. When synthesizing a polyurethane-based resin, the average number of functional groups of the isocyanate groups in the organic polyisocyanate and the average number of functional groups of the active hydrogen groups in the active hydrogen group-containing compound are adjusted to determine the conditions that do not gel and each raw material is satisfied to satisfy these conditions. It is important to formulate. The blending ratio is based on the theory of gelation calculated by JP Flory, Khun et al., And in fact, by reacting at a blending ratio considering the reactivity ratio of the reactive hydrogen group-containing compound and the reactor contained in each molecule of the organic polyisocyanate, It can manufacture without gelatinizing urethane resin.

The synthesized polyurethane-based resin contains an active hydrogen group or an isocyanate group and preferably has a number average molecular weight of 800 to 100,000, particularly 1,000 to 80,000. When the number average molecular weight of synthesize | combined polyurethane resin is too big | large, resin viscosity is high and workability worsens. Moreover, when a number average molecular weight is too small, adhesive strength will run short.

When producing a polyurethane-based resin, a conventional known method, that is, a solution reaction method in which a raw material is dissolved in an organic solvent and reacted, a solvent-free reaction method in which each raw material is sufficiently mixed and reacted under a solvent, and the like can be used.

In addition, a one-shot method for reacting an active hydrogen group-containing compound and an organic polyisocyanate at once, and an isocyanate group terminal prepolymer is first synthesized by excessively reacting an isocyanate group in an active hydrogen group-containing compound and an organic polyisocyanate first. Then, it can synthesize | combine by a well-known method, such as the initial polymer method which makes an active hydrogen group containing compound react.

In the case of the one-shot method, the ratio of isocyanate group / active hydrogen group is preferably 0.5 to 2.0, particularly 0.8 to 1.5. If it is less than 0.5, the molecular weight of polyurethane-based resin will become small too much, and a fault arises in durability. When it exceeds 2.0, there will be many isocyanates which are not involved in the reaction when synthesizing the resin.

In the case of the prepolymer method, the ratio of isocyanate group / active hydrogen group when synthesizing the prepolymer is preferably 1.1 to 5.0, in particular 1.5 to 4.0. If it is less than 1.1, the molecular weight of the prepolymer is too large to make it difficult to proceed with the subsequent reaction process. When it exceeds 5.0, adhesiveness will become inadequate.

Examples of the active hydrogen group-containing compound to be reacted after synthesizing the isocyanate group terminal prepolymer include the aforementioned polyols, polyamines, aminoalcohols and the like. Moreover, if necessary, monoamines, such as ethylamine, diethylamine, and aniline; And some terminal blockers such as monools such as methanol and ethanol.

When synthesizing an isocyanate group terminal prepolymer and a polyurethane-based resin, additives (for example, catalysts and stabilizers) commonly used in the production of polyurethane-based resins can be used. As such a catalyst, tertiary amines, such as triethylamine and triethylenediamine; Metal salts such as potassium acetate and zinc stearate; And organometallic compounds such as dibutyltin laurate and dibutyltin oxide. Examples of the stabilizer include ultraviolet stabilizers such as substituted benzotriazoles and thermal oxidation stabilizers such as phenol derivatives. The reaction temperature at the time of urethanization is 10-120 degreeC, especially 30-100 degreeC is preferable.

The hardening | curing agent for laminate adhesives of this invention, and the additives and adjuvant used conventionally for a general adhesive agent can be mix | blended with the hardening | curing agent for laminate adhesives as needed. For example, pigments, dyes, coupling agents, blockers, dispersion stabilizers, viscosity modifiers, leveling agents, gelling agents, light stabilizers, antioxidants, UV absorbers, heat resistance enhancers, plasticizers, antistatic agents , Reinforcing materials, catalysts, thixotropic agents, antibacterial agents, fungicides, lubricants, inorganic and organic fillers. The compounding method uses well-known methods, such as stirring and dispersion | distribution.

In addition, in the present invention, an organic solvent may be used in combination to improve viscosity adjustment and wettability. As an organic solvent, Aromatic solvents, such as toluene, xylene, and a sol (aromatic hydrocarbon solvent manufactured by Cosmo Petroleum Co., Ltd.), and Solvetso (aromatic hydrocarbon solvent manufactured by Exxon Chemical Company); Ketone solvents such as acetone, methyl ethyl ketone, ethyl isobutyl ketone and cyclohexanone; Alcohol solvents such as methanol, ethanol and isopropanol; Ester solvents such as ethyl acetate, butyl acetate and isobutyl acetate; Glycol ether ester solvents such as ethylene glycol ethyl ether acetate, propylene glycol methyl ether acetate, 3-methyl-3-methoxybutyl acetate, and ethyl-3-ethoxypropionate; Ether solvents, such as tetrahydrofuran and dioxane, etc. are mentioned. These solvents can be used individually or in mixture of 2 or more types.

As for the compounding ratio of the active hydrogen compound and polyisocyanate hardening | curing agent which are the subject, 1-200 weight part (ratio converted into solid content) with respect to 100 weight part of active hydrogen compounds, Especially 5-180 weight part polyisocyanate hardener is preferable. If the amount of the polyisocyanate curing agent used is too small, the durability of the crosslinked resin is insufficient, and if too large, the flexibility of the crosslinked resin is insufficient.

In the polyurethane resin used for the laminate adhesive of the present invention, other resins of 1,000 parts by weight or less may be blended with respect to 100 parts by weight of the polyurethane resin. Examples of other resins include polyamide resins, polyester resins, acrylic resins, epoxy resins, polyvinyl chloride resins, cellulose-based resins such as ethylene-vinyl acetate resins, nitrile resins, nitrocellulose, and petroleum resins.

 Since the laminate adhesive of the present invention is excellent in adhesion, durability, etc. in various base materials, it can be used in various fields as an adhesive such as film lamination, plywood, furniture, automobiles, railways, electrical appliances, non-woven fabrics, shoes, bags, etc. , Especially for film lamination. Moreover, since adhesiveness in metal and polyolefin is favorable, it is useful as an adhesive agent in lamination of metal foil, a metal vapor deposition film, a polyolefin film, etc.

Films used for lamination include stretched polypropylene, unstretched polypropylene, polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthylate, polybutylene naphthylate, nylon, low density polyethylene, medium density Polymer films such as polyethylene, high density polyethylene, ethylene-vinyl acetate copolymer, ethylene-vinyl alcohol copolymer, polyvinyl chloride, polyvinyl alcohol, polystyrene, polycarbonate, polyvinylidene chloride and cellophane; The film in which metals, such as metal foil (for example, aluminum and copper), aluminum, copper, etc. were vapor-deposited on the polymeric film, paper, the film which polymer-coated to these, etc. are mentioned.

When a polymer film is surface-treated, such as corona discharge treatment, adhesive force improves and it becomes a preferable film. In addition, the polymer coating film needs to consider the kind, quantity, and surface characteristics of the coated polymer.

As the lamination method using the laminate adhesive of the present invention, wet lamination, dry lamination, hot melt lamination, extrusion lamination, non-solvent lamination and the like can be applied.

The coating amount of the laminate adhesive is preferably from 0.5 to 10 g / m 2, particularly from 1 to 8 g / m 2, as the resin powder. If the coating amount is out of this range, the adhesive strength is likely to be insufficient.

After apply | coating an adhesive agent to a film, it is left to stand for a fixed time as needed and adhere | attached. Thereafter, if necessary, pressure or heating is performed to accelerate the curing reaction. At this time, preferable pressure is 0.01-2 Mpa per unit area or unit length, and preferable temperature is 40-150 degreeC.

In this way, not only two films are laminated but also three or more films are laminated.

Example

Although an Example demonstrates this invention in detail below, this invention is limited to an Example and is not interpreted. In the Synthesis Examples, Examples and Comparative Examples, "parts" and "%" refer to "parts by weight" and "% by weight" unless otherwise specified.

Synthesis of Polyisocyanate Curing Agent

Synthesis Example 1

Into a reactor equipped with a stirring device, a thermometer, a reflux condenser, and a nitrogen gas inlet tube, 86 parts of C-HX, which is an isocyanurate-modified type of hexamethylene diisocyanate, and 14 parts of monool (1) were added thereto at 70 ° C. It was made to react for 3 hours and the polyisocyanate hardener A was obtained. The isocyanate group content of A was 16.8%.

Synthesis Example 2

98 parts of MR-200 which is a mixture of diphenylmethane diisocyanate and polymethylene polyphenylene polyisocyanate, and 2 parts of monools (2) are thrown into the apparatus similar to the synthesis example 1, and it is made to react at 70 degreeC for 3 hours, Polyisocyanate curing agent B was obtained. The isocyanate group content of B was 30.3%.

Synthesis Example 3

86 parts of C-HX, 10 parts of monools (3) and 4 parts of monools (4) were added to the same apparatus as in Synthesis example 1, and reacted at 70 degreeC for 3 hours, and the polyisocyanate hardening | curing agent C was obtained. . Isocyanate group content of C was 17.7%.

Synthesis Example 4

98 parts of IPDI was added to the same apparatus as in Synthesis example 1, and the mixture was heated to 50 ° C. Thereafter, 2 parts of polyol (1) was added and reacted at 70 ° C for 3 hours to obtain a polyisocyanate curing agent D. The isocyanate group content of D was 37.0%.

Synthesis Example 5

Into the same apparatus as in Synthesis Example 1, 3,000 parts of HDI, 6 parts of trioctylphosphine of the uretodiolation and isocyanurate catalyst were added, and the mixture was heated to 65 to 70 ° C. without stirring and 6 at the same temperature. The reaction was time. Then 3.5 parts of phosphoric acid was added and the reaction was stopped to obtain a pale yellow reaction product having an isocyanate group content of 30.3%. Unreacted HDI was removed from the reaction product by distillation of thin film at 120 ° C. and 0.01 Torr to obtain a uretodione-modified HDI. The isocyanate group content of the product was 18.7%, and it was confirmed from the FT-IR and C ¹³ -NMR that the isocyanate group, uretodione group and isocyanurate group were present in this product. The product was heated to 180 ° C. to dissociate the uretodione group, and to determine the total amount of isocyanate groups generated by dissociating the isocyanate group and the uretodione group from the beginning, the isocyanate group content was 30.8%. The isocyanate group content produced by dissociation of the uretodione group was 12.1%. In addition, the content of isocyanurate group was 19.2%.

Subsequently, 86 parts of said uretodione-modified HDI and 14 parts of monools (1) were thrown into the apparatus similar to the synthesis example 1, and it was made to react at 70 degreeC for 3 hours, and the polyisocyanate hardener E was obtained. Isocyanate group content of E was 14.7%.

Synthesis Examples 1 to 5 are shown in Table 1 below.

Synthesis Example One 2 3 4 5 Organic Polyisocyanate (part) C-HX MR-200 IPDI Uretodione Modified HDI  86   98  86    98     86 Compound having a hydrophilic polar group and an active hydrogen group (part) Monool (1) Monool (2) Monool (3) Polyol (1)  14   2    10     2  14 Compound (part) monool (4) having a hydrophobic group and an active hydrogen group  4 Name of polyisocyanate curing agent A B C D E Isocyanate Group Content (%) 16.8 30.3 17.7 37.0 14.7

Each item in Table 1 is as follows:

C-HX: Coronate HX (manufactured by Nippon Polyurethane Co., Ltd., isocyanate group content = 21.3%);

MR-200: myrionate MR-200 (manufactured by Nippon Polyurethane Co., Ltd., isocyanate group content = 31.0%);

IPDI: isophorone diisocyanate;

HDI: hexamethylene diisocyanate;

Monool (1): Monool (number average molecular weight 400) which added EO (ethylene oxide) / PO (propylene oxide) to MeOH (methanol, initiator) so that molar ratio might be 100/0;

Monool (2): Monool (number average molecular weight 700) which added EO / PO to EtOH (ethanol, initiator) so that molar ratio might be 80/20;

Monool (3): Monool (number average molecular weight 1,000) which added EO / PO to MeOH (initiator) so that molar ratio might be 90/10;

Monool (4): ricinoleic acid methyl ester;

Polyol (1): Diol (number average molecular weight 1,000) which added EO / PO to EG (ethylene glycol, initiator) so that molar ratio might be 90/10.

Synthesis of Polyurethane Resin

Synthesis Example 6

186 parts of polyol A and 350 parts of ethyl acetate were thrown into the reactor equipped with the stirrer, the thermometer, the nitrogen sealing tube, and the cooler, and it melt | dissolved at 30 degreeC. Subsequently, 83 parts of IPDI and 0.03 part of DBTDL were added and reacted at 70 ° C for 3 hours. Subsequently, after cooling this reaction liquid to 30 degreeC, the previously prepared amine liquid which consists of 29 parts IPDA and 2 parts MEA in 350 parts MEK was thrown in, and it reacted, and obtained polyurethane-based resin PU-1 of 30% of solid content. It was.

Synthesis Example 7

246 parts of polyol B, 13 parts of NPG, and 200 parts of ethyl acetate were thrown into the apparatus similar to the synthesis example 6, and it melt | dissolved at 30 degreeC. Subsequently, 41 parts of TDI and 0.03 parts of DBTDL were added and reacted at 80 ° C for 4 hours. Since the viscosity increased as the urethanation reaction proceeded, 150 parts of ethyl acetate were added several times. When the peak of the isocyanate group disappeared in the infrared absorption analysis, 350 parts of ethyl acetate was further added and diluted to obtain a polyurethane resin PU-2 having a solid content of 30%.

Synthesis Example 8

179 parts of polyol B, 89 parts of polyol C, and 200 parts of ethyl acetate were thrown into the apparatus similar to the synthesis example 1, and it melt | dissolved at 30 degreeC. Then, 32 parts of H ₆ XDI and 0.03 parts of DBTDL were added and reacted at 80 ° C. Since the viscosity increased as the urethanation reaction proceeded, 150 parts of ethyl acetate were added several times. When the peak of the isocyanate group disappeared in the infrared absorption analysis, 350 parts of ethyl acetate was further added and diluted to obtain a polyurethane resin PU-3 having a solid content of 30%.

Synthesis Example 9

778 parts of polyol D were thrown into the apparatus similar to the synthesis example 1, and it heated at 50 degreeC. Subsequently, 222 parts of MDI was added and it reacted at 80 degreeC. The reaction was terminated when the peak of the isocyanate group disappeared in the infrared absorption analysis to obtain a polyurethane-based resin PU-4 having a solid content of 100%.

Synthesis Examples 6 to 9 are shown in Table 2 below.

Synthesis Example 6 7 8 9 Long chain polyol (part) Polyol A Polyol B Polyol C Polyol D  186   246   179 89     778 Chain extender (part) IPDA NPG  29   13 Organic Polyisocyanate (part) IPDI TDI H ₆ XDI MDI  83   41    32     222 Reaction stopper (part) MEA  2 Urethane Catalyst (Part) DBTDL  0.03  0.03  0.03 Solvent (part) Ethyl acetate MEK  350 350  700  700 Solid content (% by weight) 30 30 30 100 Polyurethane-based resin PU-1 PU-2 PU-3 PU-4

Each item in Table 2 is as follows:

Polyol A: polyesterdiol obtained from 3-methyl-1,5-pentanediol and adipic acid (number average molecular weight = 1,000);

Polyol B: polyesterdiol obtained from 1/1 mole ratio of ethylene glycol / neopentyl glycol and 1/1 mole ratio of adipic acid / isophthalic acid (number average molecular weight = 2,000);

Polyol C: rodin-based diol (KE-601, manufactured by Goten Chemical Co., Ltd., number average molecular weight = 1,000);

Polyol D: polyesterdiol obtained from 3-methyl-1,5-pentanediol and adipic acid (number average molecular weight = 500);

IPDA: isophoronediamine;

NPG: neopentylglycol;

IPDI: isophorone diisocyanate;

TDI: 2,4-tolylene diisocyanate;

H ₆ XDI: hydrogenated xylene diisocyanate;

MDI: 4,4'-diphenylmethane diisocyanate;

MEA: monoethanolamine;

DBTDL: dibutyltin dilaurate;

MEK: methyl ethyl ketone.

<Adhesion test -1>

Formulation of Adhesive

The adhesives AD-1 to AD-8 were prepared by blending the compounding ratios shown in Table 3 below. The compounding ratio disclosed in Table 3 is the numerical value converted into total solid.

Polyurethane-based resin Polyisocyanate curing agent PU-1 PU-2 PU-3 A B C D E C-L C-HL C-HX AD-1 100 15 AD-2 100 15 AD-3 100 15 AD-4 100 15 AD-5 50 50 15 AD-6 100 15 AD-7 100 15 AD-8 100 15

Each item in Table 3 is as follows:

C-L: adduct-modified curing agent of tolylene diisocyanate (Coronate L from Nippon Polyurethane Co., Ltd., solid content = 75%);

C-HL: adduct-modified curing agent of hexamethylene diisocyanate (Coronate HL from Nippon Polyurethane Co., Ltd., solid content = 75%);

C-HX: isocyanurate modified type curing agent of hexamethylene diisocyanate (Coronate HX, Nippon Polyurethane Co., Ltd., solid content = 100%).

Measurement of adhesive strength

Example 1

AD-1, corona treated PET film (film thickness: 12μ), aluminum foil (aluminum thickness: 7μ), corona treated CPP film (film thickness: 70μ) were placed in a dry laminator. To the corona treated surface of the corona treated PET film, AD-1 was applied using a gravure roll so that the coating amount was 3.5 g / m 2 as a dry amount. After apply | coating an adhesive agent, after passing through the drying furnace set to 80 degreeC, aluminum foil was adhere | attached by the adhesive roll on the conditions of 100 degreeC and 0.3 Mpa. Subsequently, AD-1 was apply | coated to the aluminum foil surface so that application amount might be 3.5 g / m <2> by dry amount. After apply | coating an adhesive agent, after passing through the drying furnace set to 80 degreeC, the corona treatment surface of the corona-treated CPP was adhere | attached with the adhesive roll on the conditions of 100 degreeC and 0.3 Mpa. The film speed was 50 m / min. After lamination, it was left at 40 ° C. for 3 days to obtain laminate film A.

The laminated film A was cut to 15 mm width, and the T-type peeling test was done in the measurement atmosphere of 300 mm / min of tensile speed, 25 degreeC, and 50% relative humidity.

Further, laminate film A was sealed by sealing three sides for 1 second at 180 ° C. and 0.3 MPa with the CPP side inward, and ketchup / salad oil / vinegar was mixed in a weight ratio of 1/1/1. The liquid was added and sealed by sealing under the same conditions as above. After boiling at 120 ° C for 30 minutes, a T-type peeling test (sample width: 15 mm, tensile strength: 300 mm / min, measurement atmosphere: 25 ° C., 50% relative humidity) was performed.

Examples 2 to 5, Comparative Examples 1 to 3

Using AD-2 to AD-8, laminate films were prepared and tested in the same manner as in Example 1.

The test results of Examples 1 to 5 and Comparative Examples 1 to 3 are shown in Table 4 below.

glue Peel Strength (gf / 15mm) Peel strength after retort (gf / 15 mm) PET / Al Al / CPP PET / Al Al / CPP Example One AD-1 400 PETf 1200 Alf 400 PETf 1100 Alf 2 AD-2 360 PETf  970 Alf 380 PETf 1050 Alf 3 AD-3 380 PETf 1080 Alf 400 PETf 1050 Alf 4 AD-4 400 PETf 1100 Alf 390 PETf 1100 Alf 5 AD-5 370 PETf 1000 Alf 350 PETf 1000 Alf Comparative example One AD-6 400 PETf  740 Alf 280 590 2 AD-7 380 PETf  680 Alf 250 580 3 AD-8 390 PETf  750 Alf 260 640

Each item in Table 4 is as follows:

PET: polyethylene terephthalate;

Al: aluminum foil;

CPP: unstretched polypropylene;

PETf: PET Material Destruction

Alf: Destruction of Al

<Adhesion test-2>

Formulation of Adhesive

It mix | blended in the compounding ratio shown in Table 5, and prepared adhesive AD-9-AD-12.

Measurement of adhesive strength

Example 6

The AD-9 was warmed to 60 ° C. and coated on a corona treated surface of a corona treated PET film (film thickness: 12 μ) with a roll coater such that the coating amount was 2.0 g / m 2. After applying the adhesive, the aluminum foil surface of the unstretched polypropylene film (film thickness: 60 mu) on which aluminum was deposited was adhered with an adhesive roll at 100 占 폚 and 0.3 MPa. The film speed was 50 m / min. After lamination, it was left to stand at 40 ° C for 3 days to obtain laminate film I.

The laminated film I was cut into 15 mm width as it was, and the T-type peeling test was done in the measurement atmosphere of 300 mm / min of tensile speed, 25 degreeC, and 50% relative humidity.

Example 7, Comparative Example 4 and Comparative Example 5

AD-10 to AD-12 were also manufactured in the same manner as in Example 6, and a laminate film was tested.

The test results of Example 6 and Example 7, Comparative Example 4 and Comparative Example 5 are shown in Table 5 below.

glue subject Hardener Peel Strength (gf / 15mm) PES PU-4 A C-HX PET / VM-CPP Example 6 AD-9 100 70 370 PETf 7 AD-10 100 70 390 PETf Comparative example 4 AD-11 100 70 250 5 AD-12 100 70 280

In Table 5, each item is as follows:

PES: polyesterdiol obtained from 30/70 molar ratio of ethylene glycol / neopentyl glycol and 60/40 molar ratio of isophthalic acid / sebacic acid (number average molecular weight = 1,000);

C-HX: isocyanurate modified type curing agent of hexamethylene diisocyanate (Coronate HX available from Nippon Polyurethane Co., Ltd.);

PET: polyethylene terephthalate;

VM-CPP: aluminum deposited unstretched polypropylene film;

PETf: Destruction of PET material.

As described above, the present invention can provide a polyisocyanate curing agent for a non-aqueous laminate adhesive having excellent heat resistance, durability, and adhesion between a metal film and a polyolefin film, and a non-aqueous laminate adhesive containing the curing agent. The adhesive can be suitably used for film lamination.

Claims (3)

A polyisocyanate curing agent for a non-aqueous laminate adhesive, characterized by containing a polyisocyanate having a hydrophilic polar group. A non-aqueous laminate adhesive comprising a polyisocyanate curing agent according to claim 1 and an active hydrogen compound. A film laminate, wherein the film is laminated using a non-aqueous laminate adhesive containing a polyisocyanate curing agent according to claim 1 and an active hydrogen compound.