JPH08291279A - Adhesive composition for laminate and production of laminated film - Google Patents

Abstract

PURPOSE: To obtain the subject composition having an excellent peeling adhesion strength, capable of curing in a short time at room temperature and excellent in productivity, working environment safety, etc., by compounding a specific polyurethane component, a uretedione-group dissociation catalyst and a coupling agent. CONSTITUTION: A polyurethane component is composed of a polyisocyanate compound component (A1 ) containing a uretedione group (a) and an isocyanurate group (b) and an active-hydrogen compound component (A2 ) having a molecular weight of 18-20000 and containing two or more than two active hydrogen groups (c) in a molecule. In the polyurethane component, an equivalent ratio of the group (c) to the isocyanate group (b) is >=1.0 and an equivalent ratio of (a)/(c) is 0.25-1.0. 100 pts.wt. of the polyurethane component (A) is compounded with 0.05-10.0 pts.wt. of a uretedione-group dissociation catalyst (B) and 0.05-10.0 pts.wt. of a coupling agent (C).

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laminating adhesive composition capable of laminating a plastic film, a metal foil or the like at room temperature in a short time, and a method for producing a laminated film. More specifically, the adhesive composition for lamination of the present invention contains at least a uretdione group and an active hydrogen group in a predetermined ratio, and further contains a polyurethane component containing an isocyanurate group, a uretdione group dissociation catalyst and a coupling agent. As an essential component, it is possible to cure by chain extension / crosslinking in a short time even at room temperature.
The present invention relates to a laminating adhesive composition containing no free polyisocyanate monomer and an isocyanate group-terminated compound, and a method for producing a laminated film.

[0002]

2. Description of the Related Art Recently, as a packaging method, composite flexible packaging is used because of its strength, product protection, workability at the time of packaging, advertising effect of packaging, large amount of plastic materials, and reduction of packaging cost due to inexpensive supply. Is developing significantly. A typical lamination method of the film used here is dry lamination suitable for a field requiring adhesive strength, heat resistance, and retort resistance. Currently, as an adhesive for dry laminating, active hydrogen groups such as hydroxyl groups are generally used because of their excellent adhesive performance, cold resistance, and heat resistance, and the wide range of application to various plastics, metal foils, and other base materials. A two-component polyurethane adhesive composed of a main agent having a curing agent and a curing agent having an isocyanate group has become the mainstream.

[0003]

However, current two-component polyurethane adhesives for lamination require a curing accelerating process called so-called aging because the curing reaction of the adhesives after film lamination is very slow. . Specifically, the laminated laminated film is 35 to 60 ° C.
It becomes necessary to cure the adhesive by aging it by storing it in the greenhouse for 3 to 5 days. At this time, since the degree of curing of the adhesive varies depending on the aging conditions, the adhesive strength of the laminated film may be affected. In this case, when aging is insufficient, delamination may occur due to poor curing of the adhesive. In particular, an aliphatic polyurethane adhesive requires a long reaction for curing. Therefore, there was a strong recognition that such an aging process is an indispensable step in the dry lamination process, and that a capital investment for installing a greenhouse for aging and a utility cost for the subsequent heat retention are naturally required. .

Further, the conventional two-component polyurethane-based adhesive for lamination is generally one in which a curing agent having an isocyanate group at the terminal of the molecular chain is added to the main agent, so that a free isocyanate monomer and an isocyanate group terminal are used. Since it contains a compound, it is not always preferable from the viewpoint of working environment. As described above, aging under heating, which is usually adopted in two-component polyurethane adhesives, is unnecessary, there is no scattering of substances such as blocked isocyanate blocking agents, and free isocyanate monomers and isocyanate groups are used. The development of a laminating adhesive that does not contain any terminal compounds in the system is revolutionary, and the development of such an adhesive is for capital investment to install a greenhouse for aging and subsequent heat retention. It does not require utility costs, etc., and further brings advantages such as improved productivity and shortened delivery time of products. Furthermore, it should be appreciated that lamination at room temperature is a very advantageous method for laminating films that are susceptible to thermal degradation. INDUSTRIAL APPLICABILITY The present invention is capable of completing a curing reaction at room temperature in a short time, does not include a free isocyanate monomer and an isocyanate group terminal compound at all, and is excellent in productivity, work environment, safety, etc. It is an object to provide an adhesive composition.

[0005]

Means for Solving the Problems As a result of intensive studies for solving the above-mentioned conventional problems, the present inventors have found that they contain at least a uretdione group and an active hydrogen group in a predetermined ratio, and further, isocyanurate. An adhesive composition comprising a polyurethane component containing a group, a uretdione group dissociation catalyst and a coupling agent can complete a curing reaction at room temperature in a short time, and a free isocyanate monomer and an isocyanate group terminal compound can be used. They have found that they can be an essential component of an adhesive composition for laminating that does not contain them, and have completed the present invention.

That is, the adhesive composition for lamination of the present invention comprises, as the polyisocyanate component (A), one or more polyisocyanate compounds (a1) containing at least a uretdione group and an isocyanurate group,
One or more active hydrogen compound components (B) having a molecular weight of 18 to 20,000 and containing two or more active hydrogen groups in the molecule, and an equivalent ratio of active hydrogen groups to isocyanate groups When the uretdione group and active hydrogen group are 1.0 or more, the equivalent ratio of uretdione group / active hydrogen group is 0.
25 to 1.0, a uretdione group dissociation catalyst 0.05 to 10.0 parts by weight, and a coupling agent 0.05 to 10.0 parts by weight based on 100 parts by weight of the polyurethane based component. It is characterized by containing.

The adhesive composition for lamination of the present invention contains, in the molecule, one or more polyisocyanate compounds (a1) containing at least a uretdione group and an isocyanurate group as the polyisocyanate component (A). One or more polyisocyanate monomer (a2) having two or more isocyanate groups, and an active hydrogen compound component having a molecular weight of 18 to 20,000 and containing two or more active hydrogen groups in the molecule (B 1) or 2 or more thereof, the equivalent ratio of the active hydrogen group to the isocyanate group is 1.0 or more, and the equivalent ratio of at least the uretdio group and the active hydrogen group is 0.25. A polyurethane component composed of ~ 1.0,
It is characterized by containing 0.05 to 10.0 parts by weight of a uretdione group dissociation catalyst and 0.05 to 10.0 parts by weight of a coupling agent with respect to 100 parts by weight of the polyurethane component.

Further, the polyisocyanate compound (a1) as the polyisocyanate component (A), which is a component of the adhesive composition for lamination of the present invention, comprises a polyisocyanate monomer and a bifunctional or higher functional polyol having a side chain. It is characterized in that the prepolymer reacted with an excess of groups contains uretdione groups and isocyanurate groups.

According to the present invention, the adhesive composition for laminating described above is applied to a first plastic film or a metal foil, dried, and then a second plastic film or a metal foil is attached thereto. The method for producing a laminated film is characterized in that the curing condition is 10 to 35 ° C. for 24 hours.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION First, a polyisocyanate compound used as a polyisocyanate component in the adhesive composition for lamination of the present invention will be described. The polyisocyanate compound (a1) of the polyisocyanate component (A) of the present invention contains at least a uretdione group and an isocyanurate group. As long as at least a uretdione group and an isocyanurate group are contained, one kind or a mixture of two or more kinds may be used. For example, a mixture of a uretdione group-containing polyisocyanate compound (dimer and polyuretdione body), an isocyanurate group-containing compound (trimer and polyisocyanurate body), and a uretdione group- and isocyanurate group-containing polyisocyanate compound, Good. The uretdione group content of the polyisocyanate compound (a1) is 8 to 25% by weight,
It is preferably 10 to 23% by weight. The isocyanurate group content is 1 to 24% by weight, preferably 3 to 20% by weight.

The polyisocyanate compound (a1)
Is a polyisocyanate compound containing, in addition to the uretdione group and the isocyanurate group, a group other than the uretdione group and the isocyanurate group derived from an isocyanate group, and may be one kind or a mixture of two or more kinds. Further, as the polyisocyanate constituting the polyisocyanate compound (a1), 1,6-hexamethylene diisocyanate is particularly suitable from the viewpoint that the produced polyisocyanate compound is in a liquid state and does not undergo yellowing.

Groups other than the uretdione group and isocyanurate group derived from the isocyanate group of the polyisocyanate compound (a1) include urethane group, urea group, carbodiimide group, uretonimine group, oxazolidone group,
Hydantoin groups and the like.

Of the polyisocyanate component (A), the polyisocyanate (a2) is a polyisocyanate having two or more isocyanate groups in the molecule, and contains a polymer thereof in addition to the free polyisocyanate monomer. The polyisocyanate (a2) can be used alone or as a mixture of two or more kinds.

The polyisocyanate compound (a of the present invention
1) As the polyisocyanate of the polyisocyanate (a2), in addition to the monomer of the free polyisocyanate, its polymer is contained. As the polyisocyanate monomer, aromatic, aliphatic or alicyclic compounds having at least two isocyanate groups in the molecule and modified products thereof are preferably used. Examples of the aromatic diisocyanate include 2,4- Tolylene diisocyanate, 2,6-tolylene diisocyanate, xylene-1,4-diisocyanate, xylene-1,3-
Diisocyanate, 4,4'-diphenylmethane diisocyanate (hereinafter abbreviated as MDI), 2,4'-diphenylmethane diisocyanate 4,4'-diphenyl ether diisocyanate, 2-nitrodiphenyl-4,4 '
-Diisocyanate, 2,2'-diphenylpropane-
4,4'-diisocyanate, 3,3'-dimethyldiphenylmethane-4,4'-diisocyanate, 4,4 '
-Diphenylpropane diisocyanate, m-phenylene diisocyanate, p-phenylene diisocyanate, naphthylene-1,4-diisocyanate, naphthylene-1,5-diisocyanate, 3,3'-dimethoxydiphenyl-4,4'-diisocyanate, etc. Examples of the diisocyanate include tetramethylene diisocyanate, hexamethylene diisocyanate (hereinafter abbreviated as HDI), lysine diisocyanate, and the like, and examples of the alicyclic diisocyanate include isophorone diisocyanate, hydrogenated tolylene diisocyanate, hydrogenated xylene diisocyanate, hydrogenated Diphenylmethane diisocyanate, tetramethyl xylene diisocyanate and the like, and modified products thereof include dimers, trimers and prepolymers of the above diisocyanates. Rimmer type modified products, carbodiimide modified products, may be exemplified a polymer of urea modified products and the like. The polyisocyanate compound (a1) also includes a polyisocyanate obtained by reacting a difunctional or higher functional polyol or the like with the diisocyanate or a polymer thereof, and a polyisocyanate that can be more preferably used is a polymer of polyisocyanate. And a polyisocyanate polyol adduct.

The polyisocyanate compound (a1), for example, the uretdione group-containing polyisocyanate compound and the uretdione group- and isocyanurate group-containing polyisocyanate compound, which are essential components in the present invention, are a dimerization reaction (uretdione reaction) of a polyisocyanate monomer, It is formed by a trimerization reaction (isocyanurate formation reaction) or the like, and specifically, for example, it can be produced as follows.

Such mixtures are prepared from the corresponding polyisocyanate monomers and / or isocyanate-terminated compounds by known uretdione-formation catalysts such as triethylphosphine, dibutylethylphosphine, tributylphosphine, tri-n-propylphosphine, tria. In the presence of trialkylphosphines such as millphosphine, tribenzylphosphine, etc., or pyridine, etc., usually at a reaction temperature of 0 to 90 ° C., without a solvent, or with an inert solvent commonly used in the polyurethane industry, for example, toluene, xylene, etc. Aromatic solvents, ketone solvents such as methyl ethyl ketone and methyl isobutyl ketone, ester solvents such as ethyl acetate and butyl acetate, glycos such as propylene glycol methyl ether acetate and ethyl-3-ethoxypropionate. The presence of ether ester-based solvents, and in some cases, can be produced in a plasticizer polyol or DOP like liquid at the reaction temperature.

When 20 to 50 mol% of isocyanate groups in the isocyanate group content have reacted with this reaction solution, for example, a solution of phosphoric acid, methyl paratoluenesulfonate, sulfur or the like is added to form a uretdione-forming catalyst. Inactivate and stop the reaction. Depending on the type of polyisocyanate used, some may be crystallized and precipitated during this reaction process. In particular, aromatic polyisocyanates generally crystallize and separate from the reaction system.

The uretdione group-containing polyisocyanate compound (that is, dimer and poly-uretdione body), the isocyanurate group-containing polyisocyanate compound (that is, trimer and polyisocyanurate body) and the uretdione group are prepared by such a method. And a mixture of the isocyanurate group-containing polyisocyanate compound and the raw material polyisocyanate monomer. By removing the raw material polyisocyanate monomer from this mixture by thin film distillation or the like, a desired mixture of the uretdione group-containing polyisocyanate compound, the uretdione group- and isocyanurate group-containing polyisocyanate compound and the like can be obtained. The higher the temperature of the reaction during the production, and the lower the content of the polyisocyanate monomer at the time of stopping the reaction, the higher the production ratio of isocyanurate groups.
In addition, the larger the amount of catalyst such as triethylphosphine, the higher the uretdione group formation rate. By controlling these reaction conditions, a polyisocyanate compound containing a specific ratio of uretdione groups and isocyanurate groups can be obtained. Furthermore, when the polyisocyanate compound (a1) used in the present invention is partially reacted in advance with a bifunctional polyol having a side chain structure before forming a uretdione group and an isocyanurate group, the active hydrogen compound component ( It may be preferable in some cases, for example, because it may improve the compatibility with B) and the adhesiveness with various substrate films. The bifunctional polyol having a side chain structure used herein has at least two hydroxyl groups and at least one hydrocarbon group in the molecule, and has a total carbon number of at least one hydrocarbon group. Is 4-35, of which one or more branched hydrocarbon groups have a total carbon number of 2-33, and are dihydric alcohols such as neopentyl glycol and 3-methyl-1,5-pentanediol. , 2,2-diethyl-1,3-propanediol, 2-n-butyl-2-ethyl-1,3-propanediol, 2,2,4-trimethyl-1,3-pentanediol, 2-ethyl- 1,3-hexanediol, 2-
n-hexadecane-1,2-ethylene glycol, 2-
n-eicosane-1,2-ethylene glycol, 2,2
-Dimethyl-3-hydroxypropyl-2,2-dimethyl-3-hydroxypropionate, hydrogenated bisphenol A and the like. Also, two or more of the above dihydric alcohols can be used in combination.

When not only the uretdione group but also the isocyanurate structure is positively introduced, excellent heat resistance and durability can be exhibited. Further, in the case where the polyisocyanate compound molecule contains a certain ratio of isocyanurate group and / or other polymer in addition to the uretdione group, the isocyanurate group may cause gelling of the polyurethane-based organic compound. A branch point can be introduced.

Therefore, in the curing step when actually used as an adhesive, it is obtained from a conventionally known uretdione group-containing polyurethane compound by a dissociation reaction of the uretdione group of the adhesive composition for lamination and a subsequent reaction with an active hydrogen group. Excellent physical properties are exhibited in a short time and at a low reaction rate, as compared with those described above. As the polyisocyanate compound (a1) and the polyisocyanate (a2), in some cases, those containing an unreacted polyisocyanate monomer can be used as they are as the polyisocyanate component (A) as the main component in the present invention.

The uretdione group- and isocyanurate group-containing polyisocyanate compound and the like excluding unreacted polyisocyanate monomer are mixed with the polyisocyanate monomer, and the active hydrogen compound component ( The reaction with B) may be preferable in some cases because problems such as gelation do not occur during the production of polyurethane-based organic compounds, and it is effective in controlling reactivity and physical properties of expression. The isocyanate group equivalent ratio of the polyisocyanate compound (a1) and polyisocyanate (a2) excluding the unreacted polyisocyanate monomer is selected from polyisocyanate (a2) / polyisocyanate compound (a1) = 0 to 5.70, 0.
10 to 4.00 is preferable, and 0.15 to 3.00 is more preferable.

Active hydrogen compound component (B) in the present invention
Has a molecular weight of 18 to 20,000 and contains two or more active hydrogen groups in the molecule. For example, in addition to water, polyol, polyamines containing amino groups, urea resins, melamine resins, epoxy resins, polyester resins,
Those containing one kind or two or more kinds selected from acrylic resin, polyvinyl alcohol and the like are preferable. As this polyol, any polyol can be used as long as it contains an active hydrogen group, and since the polyisocyanate component (B) has an isocyanate group of two or more functional groups, it can be used in the production of a polyurethane-based organic compound. In order to prevent gelation, polyols having a low functional group number such as bifunctional are suitable.

Examples of polyols include polyester polyols, polyester amide polyols, polyether polyols, polyether ester polyols, polycarbonate polyols and the like, but polyester polyols are particularly suitable. Among these polyols, examples of polyester polyols and polyester amide polyols include succinic acid, adipic acid (hereinafter abbreviated as AA), sebacic acid, azelaic acid, terephthalic acid (hereinafter abbreviated as TP), and isophthalic acid (hereinafter abbreviated as IP). , Dicarboxylic acids such as hexahydroterephthalic acid and hexahydroisophthalic acid, their acid esters and acid anhydrides, and ethylene glycol, 1,3-propylene glycol, 1,2-propylene glycol (hereinafter 1,2-
Abbreviated as PG), 1,4-butylene glycol (hereinafter, 1,
4-BG), 1,5-pentane glycol, 1,
6-hexane glycol (hereinafter abbreviated as 1,6-HG),
3-methyl-1,5-pentane glycol, 2-butyl-2-ethyl-1,3-propanediol, 2-ethyl-1,3-hexanediol, neopentyl glycol, 1,8-octane glycol, 1, 9-nonanediol, diethylene glycol, cyclohexane-1,4
-Diol, cyclohexane-1,4-dimethanol,
Dimer acid diol, trimethylolpropane (hereinafter T
Abbreviated as MP), glycerin, hexanetriol, N,
N, N ', N'-tetrakis (2-hydroxypropyl) ethylenediamine, glycol such as ethylene oxide or propylene oxide adduct of bisphenol A, or hexamethylenediamine, tolylenediamine, xylenediamine, isophoronediamine, ethylenediamine, mono It can be obtained by a dehydration condensation reaction with a diamine such as ethanolamine or isopropanoltriamine, triamine or aminoalcohol alone or a mixture thereof.

Furthermore, polyesters such as lactone-based polyester polyols obtained by ring-opening polymerization of cyclic ester (ie, lactone) monomers such as ε-caprolactone, alkyl-substituted ε-caprolactone, δ-valerolactone, and alkyl-substituted δ-valerolactone. There is a polyol. There is a close relationship between the adhesive strength of the base film and the type of polyester polyol, and it is necessary to select the polyester polyol according to the type of base film used. For adhesion of polyethylene terephthalate film and polyolefin film which are widely used, phthalic acid type polyester polyols such as TP and IP and / or polyester amide polyols such as isophorone diamine and monoethanol amine are suitable.

As the polyether polyol, for example,
Examples thereof include polyethylene glycol, polypropylene ether polyol, polytetramethylene ether polyol and the like. Examples of the polyether / ester polyol include polyester polyols produced from the above polyether polyol and the above-mentioned dicarboxylic acid or acid anhydride. Polycarbonate polyols are obtained, for example, from the reaction of hexane glycol, 3-methyl-1,5-pentanediol, 1,4-cyclohexanedimethanol and the like with diethyl carbonate and diphenyl carbonate.
80, Nipporan 981 (manufactured by Nippon Polyurethane Industry Co., Ltd.) and the like.

Further, the monomolecular diols and triols mentioned as the raw materials of the polyester polyol, that is, ethylene glycol, 1,3-propylene glycol, 1,
2-PG, 1,4-BG, 1,5-pentane glycol, 1,6-HG, 3-methyl-1,5-pentane glycol, neopentyl glycol, 2-butyl-2-ethyl-1,3- Propanediol, 1,8-octane glycol, 1,9-nonanediol, diethylene glycol, cyclohexane-1,4-diol, cyclohexane-1,4-dimethanol, dimer acid diol, T
MP, glycerin, hexanetriol, quadrol or ethylene oxide or propylene oxide adduct of bisphenol A can also be used in the present invention as the polyol.

Examples of polyamines containing amino groups and the like include short-chain diamines, triamines, aromatic diamines, and polyether polyamines in which the ends of polyethers are amino groups. Further, urea resin, melamine resin, epoxy resin, polyester resin, acrylic resin, polyvinyl alcohol and the like are generally known in the polyurethane industry, and if they contain two or more active hydrogen groups, the active hydrogen compound component (b ) Can be used in whole or in part.

The molecular weight of these active hydrogen compound components (B) is 18 to 20,000, and particularly 62 to 10.0.
00 is preferable. If the molecular weight is too high, the amount of uretdione groups, isocyanurate groups, urethane groups, etc. introduced decreases, and the toughness and strong cohesive force of the polyurethane resin decrease, which is not preferable. If the molecular weight is too small, the polyurethane resin tends to become brittle, which is not preferable. The molecular weight must be appropriately selected depending on the application, and it is preferable to use a low molecular weight one in order to increase the heat resistance and cohesive energy of the adhesive.

Next, the production of the polyurethane-based component (organic compound), which is an essential component of the adhesive composition for lamination of the present invention, comprises the above polyisocyanate component (A) and the active hydrogen compound component (B). At least a uretdione group obtained by reacting the polyisocyanate component (A) with an excess of active hydrogen groups in the active hydrogen compound component (B) in an equivalent ratio of more than 1.0. The active hydrogen group is contained in an equivalent ratio of uretdione group / active hydrogen group = 0.25 to 1.0.

The above-mentioned active hydrogen group excess condition is a condition necessary for the produced polyurethane organic compound to have an active hydrogen group without leaving an isocyanate group, and is actually a polyisocyanate derived from the isocyanurate group content or the like. Depending on the average number of functional groups of the component (A) and the average number of functional groups of the active hydrogen compound component (B) due to introduction of triol and the like,
It is important to determine the conditions under which gelation does not occur during the production of the polyurethane precursor, mix so as to satisfy this condition, and keep the reaction under the temperature condition at which the uretdione group opens to cause the reaction. The mixing ratio is J. P. Flory, Khu
According to the gelation theory in which n and the like are theoretically calculated, in practice, by reacting at a blending ratio taking into account the reactivity ratios of the reactive groups contained in each molecule of the components (a) and (b), The polyurethane-based organic compound can be produced without gelation and does not contain a free isocyanate monomer and an isocyanate group-terminated compound.

The polyurethane organic compound is in a molten state,
In a bulk state, or as required, an inert solvent commonly used in the polyurethane industry, for example, an aromatic hydrocarbon solvent such as toluene and xylene, an ester solvent such as ethyl acetate and butyl acetate, a ketone solvent such as methyl ethyl ketone and cyclohexanone. , Ethylene glycol ethyl ether acetate, propylene glycol methyl ether acetate, ethyl-3-ethoxypropionate and other glycol ether ester solvents, tetrahydrofuran, dioxane and other ether solvents, dimethylformamide, dimethylacetone, N-methylpyrrolidone, furfural Using one or more polar solvents such as
Temperature conditions at which the uretdione group does not open, preferably 10
It can be produced by uniformly mixing and reacting each component at 0 ° C. or less in the above-mentioned blending condition range. As the reaction device, any device may be used as long as the above-mentioned homogeneous reaction can be achieved, and examples thereof include a reaction kettle equipped with a stirring device, a kneader, and a mixing and kneading device such as a uniaxial or multiaxial extrusion reactor. In order to accelerate the reaction, a metal catalyst such as dibutyltin dilaurate or a tertiary amine catalyst such as triethylamine, which is commonly used in the production of polyurethane, can be used as a catalyst.

The polyurethane-based organic compound produced in this manner is the polyisocyanate compound (a
1) and (a2) may contain a group derived from an isocyanate group such as an isocyanurate group, a urethane group, a carbodiimide group, a uretonimine group, an oxazolidone group and a hydantoin group in addition to the uretdione group and the active hydrogen group. Substantially free of isocyanate group, uretdione group and active hydrogen group
Active hydrogen group = 0.25-1.0, preferably 0.35-
It must be contained in a ratio of 0.75.

This is a regulation of the equivalent ratio when the uretdione group is ring-opened by heating or the like. When the ratio of the uretdione group to the active hydrogen group is set to a ratio at which the concentration of the uretdione group becomes excessive, the present invention can be used. The adhesive composition includes a cross-linking / chain extension due to a reaction with moisture in the environment, a urethane bond, a reaction to an allophanate or a buret due to a reaction with a urea bond, and a polymerization reaction with an isocyanate group alone, such as carbodiimidization and isocyanate. It can be chain extended and / or crosslinked by nurate formation or the like, or can be a thermoplastic polymer resin when the active hydrogen groups are excessive.

Next, the compounding of the laminating adhesive composition of the present invention will be described. In the adhesive composition for laminating containing the polyurethane-based organic compound as a main component, the uretdione group of the polyurethane-based organic compound, the active hydrogen group of the polyurethane-based organic compound and the active hydrogen compound mixed at the time of blending the adhesive composition The equivalent ratio of active hydrogen groups to total active hydrogen groups is uretdione groups / total active hydrogen groups = 0.25 to 1.0, preferably 0.35 to 0.7.
5, an active hydrogen compound such as one or more selected from the above-mentioned polyols, amino group-containing polyamines, urea resins, melamine resins, epoxy resins, polyester resins, acrylic resins, polyvinyl alcohols, etc. You may mix | blend the active hydrogen compound containing.

The equivalent ratio of uretdione groups to total active hydrogen groups in the adhesive composition for lamination containing the active hydrogen compound of the present invention is in the range of uretdione groups / total active hydrogen groups = 0.5 to 1.0. When the uretdione group concentration is excessive, crosslinking / chain extension due to reaction with moisture in the environment, urethane bond, reaction with allophanate or buret due to reaction with urea bond, and polymerization reaction with isocyanate alone, for example, carbodiimidization It is also possible to chain extend and / or crosslink by isocyanurate formation, or conversely, when the active hydrogen group excess condition is set in the range of uretdione group / total active hydrogen group = 0.25 to 0.5, It can be a thermoplastic polymer resin.

In the adhesive composition of the present invention, the uretdione group contained therein is dissociated, and a polyurethane resin is formed by chain extension and / or cross-linking curing reaction with an active hydrogen group to give excellent adhesive properties and excellent adhesive properties. It is considered that coatability and workability are also exhibited. The adhesive composition of the present invention does not have to completely react with the uretdione group in the case where the uretdione group remains to provide excellent adhesive properties even if the uretdione group remains. The polyurethane-based organic compound described above may be in a liquid state, a solid state, a powdered state, or the like in a normal state, and in order to improve the function as an adhesive, the polyurethane-based organic compound as an essential component may be added as necessary. , Anti-gelling agents such as ester / urethane exchange reaction inhibitors, antioxidants, UV absorbers, hydrolysis inhibitors, dyes, pigments, leveling agents, flame retardants, viscosity modifiers to prevent gelation during storage Add flowability improver, plasticizer, thixotropic agent, filler, etc. to make an adhesive. The adhesive composition of the present invention prepared here may be in a liquid state, a solid state, a powder state or the like in a normal state.

Next, the uretdione group dissociation catalyst blended in the present invention will be described. It is the uretdione group dissociation catalyst that imparts a practical curing rate at room temperature to the adhesive composition for lamination of the present invention. Since the uretdione group dissociation catalyst can lower the dissociation temperature of the uretdione group of the polyurethane-based organic compound, the curing of the resin proceeds more rapidly at room temperature as compared to when the catalyst is not added. The degree of decrease in the dissociation temperature of the uretdione group and the subsequent curing rate largely depend on the type and amount of the catalyst to be added, but by appropriately selecting these, it is practical even in the temperature range near room temperature. It is possible to obtain a high curing rate.

However, for example, the amount of catalyst added is 0. 0 with respect to 100 parts by weight of the resin solid content of the polyurethane organic compound.
When the amount is less than 05 parts by weight, the effect of accelerating the curing reaction due to the addition of the catalyst is difficult to appear. Further, when it exceeds 10.0 parts by weight, there are adverse effects such that the curing speed is too fast, coating becomes difficult, and hydrolysis of the adhesive composition after curing may be promoted. Absent.

Therefore, the addition amount of the uretdione group dissociation catalyst is 0.05 to 10.0 parts by weight, preferably 0.1% to 100 parts by weight of the resin solid content of the polyurethane organic compound.
It is desirable that the amount be 1% to 5.0 parts by weight.

The uretdione group dissociation catalyst described here is
Transesterification catalysts, urethanization catalysts, blocked isocyanate dissociation catalysts, include those generally known as isocyanurate formation catalysts, specifically dibutyltin dilaurate, tin-based catalysts such as stannas octoate,
Triethylenediamine, triethylamine, N, N,
N ', N'-tetramethylpropylenediamine, N,
N, N ', N'-tetrakis (2-hydroxypropyl) ethylenediamine, N-methylmorpholine, 1,2
-Dimethylimidazole, 1,5-diaza-bicyclo (4,3,0) nonene-5,1,8-diazabicyclo (5,4,0) -undecene-7 (hereinafter abbreviated as DBU), of these amine-based catalysts Various amine salt catalysts such as borane salt, DBU phenol salt, DBU octylate salt, DBU carbonate salt, magnesium naphthenate, lead naphthenate,
Carboxylates such as CH ₃ COO ⁻ K ⁺ , trialkylphosphines such as triethylphosphine and tribenzylphosphine, alkoxides such as CH ₃ ONa,
Examples include zinc-based organometallic catalysts. Of these, DBU and various acid salts of DBU can be preferably used in consideration of the catalytic effect and the stability of the adhesive composition after addition.

Examples of the coupling agent used in the present invention include silane coupling agents, titanate coupling agents, aluminum coupling agents and the like. The amount of the coupling agent added is 0.05 to 10.0 with respect to 100 parts by weight of the resin solid content of the polyurethane organic compound.
Parts by weight are preferred. Furthermore, it is preferably 0.1 to 2.0 parts by weight. The addition amount shown here is calculated in consideration of the coating area of the base film of the coupling agent, the coating efficiency, and the like, in consideration of the balance between the adhesive force and the price.

Examples of the silane coupling agent include vinylsilane compounds such as γ- (methacryloxypropyl) trimethoxysilane and vinyltriethoxysilane, and β-.
Epoxysilane compounds such as (3,4-epoxycyclohexyl) ethyltrimethoxysilane and γ-glycidoxypropyltrimethoxysilane, γ-aminopropyltriethoxysilane and N-β (aminoethyl) γ-aminopropylmethyldimex An aminosilane compound such as silane and a mercaptosilane compound such as γ-mercaptopropyltrimethoxysilane can be preferably used.

Examples of titanate coupling agents include tetra-n-butoxytitanium, tetraisopropoxytitanium, bis [2-[(2-aminoethyl) amino] ethanolate] [2-[(2-aminoethyl) amino). Ethanolate-0] (2-propanolate) titanium, tris (isooctadecanoate-0) (2-propanolate) titanium, bis (ditridecylphosphite-
0 ") tetrakis (2-propanolate) dihydrogen titanate, bis (dioctyl phosphite-0")
Tetrakis (2-propanolate) dihydrogen titanate, tris (dioctyl phosphite-0 ″) (2
-Propanolate) Titanium, Bis (dioctylphosphite-0 ") [1,2-ethanediolate (2-)
--0,0 '] titanium, tris (dodecylbenzene sulfonate-0) (2-propanolate) titanium, tetrakis [2,2-bis [(2-propenyloxy) methyl] -1-butanolate titanate and the like. As a product, Plenact KR TTS, KR
46B, KR 55, KR 41B, KR 38S,
KR 138S, KR 238S, 338X, KR 1
2, KR 44, KR9SA, KR 34S (all manufactured by Ajinomoto Co., Inc.) and the like can be preferably used.

As the aluminum-based coupling agent,
Acetoalkoxyaluminum diisopropylate and the like can be mentioned, and as a commercial product, Planeact AL-M (manufactured by Ajinomoto Co., Inc.) can be preferably used.

Of the above coupling agents, epoxysilane, aminosilane, phosphoric acid titanate and the like are preferable in view of improving the adhesive strength to polyethylene terephthalate film, nylon film, polyolefin film and the like which are widely used.

The plastic film used for laminating in the present invention is a stretched polypropylene (hereinafter referred to as O
PP, abbreviated polypropylene (hereinafter abbreviated as CPP), polyester (hereinafter abbreviated as PET), nylon (hereinafter abbreviated as NY), low density polyethylene (hereinafter abbreviated as PE), high density polyethylene (hereinafter abbreviated as HDPE) ,
Ethylene-vinyl acetate copolymer (hereinafter abbreviated as EVA), polyvinyl alcohol (hereinafter abbreviated as PVA), ethylene vinyl alcohol copolymer (hereinafter abbreviated as EVOH), polystyrene (hereinafter abbreviated as PS), polycarbonate (hereinafter PC)
Abbreviated), polyvinylidene chloride (hereinafter abbreviated as PVDC), polyvinyl chloride (hereinafter abbreviated as PVC), aluminum, copper, paper and the like, and films coated with these. These plastic films are
It is preferable to perform an appropriate surface treatment such as corona discharge treatment before laminating in order to improve the adhesive force. Also,
Since the polymer-coated film may cause problems such as generation of bubbles and reduction in adhesive strength, it is necessary to consider in advance the type of polymer to be coated, the coating amount, surface characteristics, and the like.

Next, a method of laminating films will be described.
The laminating adhesive of the present invention can be used by known laminating methods such as dry lamination, hot melt lamination, and extrusion lamination. The laminated films can complete the curing reaction by aging at room temperature for about 1 day.

[0048]

EXAMPLES Examples and comparative examples of the present invention will now be described in detail, but the present invention is not limited to these examples. Unless otherwise specified, "parts" and "%" in the examples mean "parts by weight" and "% by weight", respectively. In addition, the uretdione group content and the isocyanurate group content in the examples are obtained by converting each functional group into an isocyanate group content.

[Synthesis of Polyisocyanate Component (a1)] Synthesis Example 1 A reactor equipped with a stirrer, a thermometer, a nitrogen seal tube and a cooler was charged with HDI (manufactured by Nippon Polyurethane Industry Co., Ltd., having an isocyanate group content of 49.9%). 3000 parts of solid content 100%) and 23 parts of 2-n-butyl-2-ethyl-1,3-propanediol are charged, the inside of the reactor is replaced with nitrogen, and the reaction temperature is heated to 60 to 70 ° C while stirring. Then, the mixture was reacted at the same temperature for 3 hours. The isocyanate content of the reaction liquid at this time was 49.1%. Next, 6.0 parts of tributylphosphine was charged as a catalyst and stirred at 65 to 70 ° C.
And react at the same temperature for 6 hours, and then add phosphoric acid 3.5.
The reaction was stopped by adding parts. Isocyanate group content 3
A 0.3% pale yellow reaction product solution was obtained. Unreacted HDI was removed from this reaction product solution by distillation. The product had an isocyanate group content of 21.1%, and FT-IR and ¹³ C-NMR confirmed that the product had isocyanate groups, uretdione groups and isocyanurate groups. The isocyanate group content was 37.5%, which was obtained by reacting with dibutylamine (hereinafter abbreviated as DBA) at the boiling point of propylene glycol methyl ether acetate (hereinafter abbreviated as PGM-Ac), which is a high-boiling solvent, and back titrating with an aqueous hydrochloric acid solution. Therefore, the content of isocyanate groups produced by the dissociation of uretdione groups was 16.4%. The isocyanurate group content was 12.5%. This uretdione group- and isocyanurate group-containing polyisocyanate compound is designated as polyisocyanate A.

Synthesis Example 2 In a reactor equipped with a stirrer, a thermometer, a nitrogen seal tube and a condenser, 3000 parts of HDI (manufactured by Nippon Polyurethane Industry Co., Ltd., isocyanate group content 49.9%, solid content 100%) and a catalyst were used. Tributylphosphine (6.5 parts) was charged, the reaction was carried out at 50 to 55 ° C. for 8 hours while stirring, and then 1.9 parts of phosphoric acid was added to stop the reaction. The product had an isocyanate group content of 37.3%, FT-IR and ¹³
From C-NMR, it was confirmed that an isocyanate group, a uretdione group and an isocyanurate group were present in this product. Isocyanate group content determined by reacting with DBA at the boiling point of PGM-Ac and back titrating with an aqueous solution of hydrochloric acid 44.
5%, and thus the content of isocyanate groups formed by dissociation of uretdione groups was 7.2%. The isocyanurate group content was 5.5%. This uretdione group- and isocyanurate group-containing polyisocyanate compound is designated as polyisocyanate B.

[Synthesis of Polyurethane Organic Compound] Example 1 In a reactor equipped with a stirrer, a thermometer, a nitrogen seal tube and a condenser, polyisocyanate A (isocyanate group content 21.1%, uretdione group content 16. 4%, isocyanurate group content 12.5%) 100 parts, MDI 189 parts, and aromatic polyester diol of molecular weight 2000 (IP
/ TP / AA = 5/5/1 molar ratio and NPG / HG / EG
= 2/1/2 mole ratio polyester, hereinafter PES
-A)), 681 parts of hexamethylene adipate diol having a molecular weight of 2000, 3026 parts of toluene and 4540 parts of ethyl acetate were added, and the mixture was reacted at 70 ° C. After 3 hours, it was confirmed by FT-IR that the absorption peaks of the isocyanurate group and the uretdione group did not change from those at the start of the reaction, and that the absorption peak of only the isocyanate group disappeared, the urethanization was completed, and the polyurethane organic compound was removed. Obtained. To this, 38 parts of aminosilane, KBE903 (manufactured by Shin-Etsu Chemical Co., Ltd.) was added.

Example 2 Polyisocyanate B synthesized in Reference Synthesis Example 2 was placed in a reactor equipped with a stirrer, a thermometer, a nitrogen seal tube and a condenser.
(Isocyanate group content 37.3%, uretdione group content 7.2%, isocyanurate group content 5.5%) 100
Parts and molecular weight 2000 PES-A489 parts and molecular weight 20
3-methyl-1,5-pentane adipate diol of 00, 350 parts of ethylene glycol and 5 parts of ethyl acetate
089 parts was added and the reaction was carried out at 70 ° C. 5 hours later, FT
In -IR, absorption of isocyanurate group and uretdione group did not change from that at the start of the reaction, absorption of only isocyanate group disappeared and urethanization was completed, and a polyurethane organic compound was obtained. To this, 16 parts of epoxysilane, KBM303 (manufactured by Shin-Etsu Chemical Co., Ltd.) was added.

Example 3 Polyisocyanate A synthesized in Reference Synthesis Example 1 was placed in a reactor equipped with a stirrer, a thermometer, a nitrogen seal tube and a condenser.
(Isocyanate group content 21.1%, uretdione group content 16.4%, isocyanurate group content 12.5%) 1
00 parts and isophorone diisocyanate 167 parts and PES
-A1588 parts and 3-methyl-1,5 with a molecular weight of 6000
1360 parts of pentane adipate diol and 3200 parts of ethyl acetate were added and reacted at 70 ° C. 5 hours later
In FT-IR, the absorption of isocyanurate group and uretdione group did not change from that at the start of the reaction, the absorption of only isocyanate group disappeared and the urethane formation was completed, and a polyurethane organic compound was obtained. To this was added 48 parts of a titanate-based coupling agent, Planeact KR138S (manufactured by Ajinomoto).

Comparative Example 1 255 parts of MDI, 681 parts of hexamethylene adipate diol having a molecular weight of 2000, 3026 parts of toluene and 4540 parts of ethyl acetate were added to a reactor equipped with a stirrer, a thermometer, a nitrogen seal tube and a condenser, and 70 parts The reaction was carried out at ° C. After 3 hours, it was confirmed by FT-IR that the isocyanate group had disappeared, and a polyurethane organic compound was obtained.
Aminosilane, KBE903 (made by Shin-Etsu Chemical Co., Ltd.)
38 parts were added.

Comparative Example 2 In a reactor equipped with a stirrer, a thermometer, a nitrogen seal tube and a condenser, 80 parts of HDI and PES-A4 having a molecular weight of 2000 were used.
89 parts and 350 parts of 3-methyl-1,5-pentane adipate diol having a molecular weight of 2000 and 350 parts of ethylene glycol
And 1089 parts of ethyl acetate were added, and the mixture was reacted at 70 ° C. After 5 hours, it was confirmed by FT-IR that the isocyanate group had disappeared, and a polyurethane organic compound was obtained.
To this, 16 parts of epoxysilane, KBM303 (manufactured by Shin-Etsu Chemical Co., Ltd.) was added.

Comparative Example 3 50 parts of HDI and 1 of isophorone diisocyanate were placed in a reactor equipped with a stirrer, a thermometer, a nitrogen seal tube and a condenser.
67 and 12,000 parts of PES-A having a molecular weight of 2000, 1360 parts of 3-methyl-1,5-pentane adipate diol having a molecular weight of 6000 and 3200 parts of ethyl acetate were added, and
The reaction was performed at 0 ° C. After 5 hours, it was confirmed by FT-IR that the isocyanate group had disappeared, and a polyurethane organic compound was obtained. 48 parts of Preact KR138S (manufactured by Ajinomoto Co.), a titanate coupling agent, was added thereto.

[Evaluation of Adhesive Strength] In Examples 1 to 3 and Comparative Examples 1 to 3, peeling adhesive strength from various adherends was measured under the following adhesive conditions. The results are shown in Table 1. Added catalyst: DBU phenol salt Added amount of catalyst: 0.4 part relative to solid content of polyurethane organic compound resin Solid content of adhesive: 25% (diluted with ethyl acetate) Application amount: 3.0 g / m ² dry Temperature: 80 ° C. Drying time: 30 seconds Aging condition: 25 ° C. × 1 day Peeling adhesion strength: According to JIS K 6854. T-type peel test Tension speed 200 mm / min

[0058]

[Table 1]

[0059]

As described above, it was found that the laminating adhesive composition of the present invention has a good peel adhesion strength to various adherends at room temperature in a short time. Furthermore, the adhesive composition for lamination of the present invention is a system containing no free polyisocyanate monomer and isocyanate group-terminated compound. Therefore, according to the present invention, it is possible to provide a laminating adhesive composition which can be cured at room temperature for a short time and is excellent in productivity, work environment safety and the like.

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Claims (4)

[Claims] 1. A polyisocyanate component (A),
A polyisocyanate compound (a1) containing at least a uretdione group and an isocyanurate group, and a molecular weight of 1
An active hydrogen compound component (B) having a molecular weight of 8 to 20,000 and containing two or more active hydrogen groups in the molecule, and the equivalent ratio of active hydrogen groups to isocyanate groups is 1.0 or more, and uretdione Group and active hydrogen group are uretdione groups /
A polyurethane-based component having an active hydrogen group equivalent ratio of 0.25 to 1.0, and uretdione group dissociation catalyst 0.05 to 10 parts by weight per 100 parts by weight of the polyurethane-based component.
An adhesive composition for laminating comprising 0 part by weight and 0.05 to 10.0 parts by weight of a coupling agent. 2. As the polyisocyanate component (A),
A polyisocyanate compound (a1) containing at least a uretdione group and an isocyanurate group and 2 in the molecule
A polyisocyanate (a2) having at least two isocyanate groups and an active hydrogen compound component (B) having a molecular weight of 18 to 20,000 and containing at least two active hydrogen groups in the molecule, based on the isocyanate groups. And an equivalent ratio of active hydrogen groups is 1.0 or more, and a polyurethane-based component composed of at least an uretdione group and an active hydrogen group in an equivalent ratio of uretdione groups / active hydrogen groups of 0.25 to 1.0,
An adhesive composition for laminating characterized by containing 0.05 to 10.0 parts by weight of a uretdione group dissociation catalyst and 0.05 to 10.0 parts by weight of a coupling agent with respect to 100 parts by weight of the polyurethane-based component. Stuff. 3. A polyisocyanate compound (a1) as the polyisocyanate component (A) comprises a prepolymer obtained by reacting a polyisocyanate monomer and a bifunctional or more functional polyol having a side chain in excess of an isocyanate group, and a uretdione group and an isocyanate. It contains a nurate group, The adhesive composition for lamination of Claims 1-2 characterized by the above-mentioned. 4. The adhesive composition for laminating according to claim 1, 2, or 3 is applied to a first plastic film or metal foil and dried, and then a second plastic film or metal foil is applied thereto. Curing condition after bonding is 10-3
A method for producing a laminated film, which is at 5 ° C. for 24 hours.