JP4660677B2 - Solvent-free two-component curable adhesive composition - Google Patents

Description

【００６８】
【表２】

[0001]
BACKGROUND OF THE INVENTION
TECHNICAL FIELD The present invention relates to a solvent-free two-component curable adhesive for laminating and a laminating method, and more particularly, to a solvent-free two-component curable adhesive for laminating useful for producing packaging materials such as foods, beverages, and pharmaceuticals. The present invention relates to a laminating method.
[0002]
[Prior art]
Laminated composite films containing metal foil such as aluminum foil are widely used as packaging materials for foods, beverages, pharmaceuticals and the like. This laminated composite film can be obtained by bonding at least one surface of a metal foil and various plastic films with an adhesive.
[0003]
Specifically, when a film is bonded to both surfaces of a metal foil, first, the first plastic film is bonded to one surface of the metal foil with an adhesive (first laminating), wound up, and laminated composite After the film roll is manufactured, the composite film is drawn out from the roll, and another plastic film is bonded to the other surface of the metal foil (second laminating) to form a roll again. In addition, if necessary, another plastic film may be bonded together (third lami, fourth lami, etc.).
[0004]
Conventionally, as the adhesive for laminating, a two-component curable organic solvent-based adhesive in which at least one selected from polyester polyol, polyether polyol and polyurethane polyol and a polyisocyanate compound are used has been used. .
[0005]
In recent years, there has been a shift to solvent-free organic solvent adhesives in response to measures for labor environment and solvent regulations. Therefore, an adhesive composition in which a polyol component and a polyisocyanate component are blended has been used as a solventless laminate adhesive.
[0006]
However, with the conventional solvent-free adhesive, if the roll of the first laminate is left unattended, blocking occurs due to the adhesive passing through the fine pinholes of the metal foil, during the feeding of the composite film and the process of the second laminate Problems such as film cutting occur. This problem is more likely to occur as the thickness of a metal foil such as an aluminum foil becomes smaller. For example, when the tension at the time of winding after the end of the first lamination is increased, two solvent-free liquids are used. When the mold adhesive is cured at a high temperature, it is likely to occur due to a large amount of adhesive applied.
[0007]
[Problems to be solved by the invention]
Accordingly, an object of the present invention is to provide a solventless two-component curable adhesive composition for laminating and a laminating method that can prevent the occurrence of blocking due to leaching of the adhesive from the metal foil.
[0008]
Another object of the present invention is to provide a solventless two-component curable adhesive composition for laminating and a laminating method that can prevent blocking even when the thickness of a metal foil such as an aluminum foil is small.
[0009]
Still another object of the present invention is to provide a solventless two-component curable adhesive composition for laminating and a laminating method that can suppress the occurrence of blocking even when laminated under severe conditions.
[0010]
[Means for Solving the Problems]
As a result of intensive studies to achieve the above-mentioned object, the present inventors have used a solvent-free two-component curable laminate adhesive composition containing a polyol component and a polyisocyanate component and having a specific viscosity as a mixture. The inventors have found that blocking due to the leaching of the adhesive from the metal foil does not occur and completed the present invention.
[0011]
That is, the solventless two-component curable adhesive composition of the present invention includes a polyol component (A) and a polyisocyanate component (B), and at 80 ° C. immediately after mixing the component (A) and the component (B). The viscosity is 900 mPa · s or more. Component (A) may be a polyester polyol obtained from at least one polybasic acid selected from the group consisting of aromatic dicarboxylic acids and aliphatic dicarboxylic acids and a polyhydric alcohol. The number average molecular weight of the component (A) may be 800 or more (especially 800 to 5000), and the viscosity of the component (B) at 25 ° C. may be 20000 mPa · s or more (particularly 20000 to 1000000 mPa · s). . The component (B) is selected from a reaction product (B1) and a polyisocyanate derivative (B2) of at least one selected from a polyhydric alcohol, a polyester polyol, a polyether polyol, a polycarbonate polyol and a polyurethane polyol, and a polyisocyanate. At least one (particularly a component comprising a derivative of at least one diisocyanate selected from the group consisting of araliphatic diisocyanates, alicyclic diisocyanates and aliphatic diisocyanates), and having a plurality of isocyanate groups at the ends It's okay. The equivalent ratio (NCO / OH) of the isocyanate group of the component (B) to the hydroxyl group of the component (A) is about 0.4 to 10 (particularly 0.5 to 5). The viscosity at 80 ° C. within 5 minutes after mixing the component (A) and the component (B) is particularly preferably about 900 to 5000 mPa · s. The composition of the present invention may further contain an adhesion improver (especially a coupling agent, phosphorus oxyacid, epoxy resin, etc.). Furthermore, the composition of the present invention may be a composition for laminating a metal foil having a thickness of 5 to 15 μm and a plastic film.
[0012]
The present invention also includes a method of laminating a metal foil and a plastic film using the above composition.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
[(A) Polyol component]
As the polyol component, for example, at least one selected from polyester polyol, polyether polyol, polycarbonate polyol, polyurethane polyol and the like can be used, and the viscosity at 80 ° C. immediately after mixing the component (A) and the component (B) is used. As long as is 900 mPa · s or more, the form (linear, branched, etc.) of the polyol component is not particularly limited.
[0014]
Polyester polyol is a conventional esterification reaction, that is, a condensation reaction between a polybasic acid and a polyhydric alcohol, a transesterification reaction between an alkyl ester of a polybasic acid and a polyhydric alcohol, a lactone and a polyhydric alcohol and / or a polyhydric alcohol. It can be obtained by a ring-opening polymerization reaction with a basic acid.
[0015]
Polybasic acids or alkyl esters thereof include aliphatic dicarboxylic acids such as succinic acid, adipic acid, azelaic acid, sebacic acid, dodecanedioic acid and dimer acid, and alicyclic dicarboxylic acids such as hexahydrophthalic acid and tetrahydrophthalic acid. Aromatic dicarboxylic acids such as phthalic acid, isophthalic acid, terephthalic acid, etc., or dialkyls thereof (for example, C _1-6 Alkyl ester), or a mixture thereof.
[0016]
Examples of the polyhydric alcohol include alkanediol (ethylene glycol, propylene glycol, 1,4-butanediol, 1,3-butanediol, 2-methyl-1,3-propanediol, 1,5-pentanediol, 3 -Methyl-1,5-pentanediol, 2,4-diethyl-1,5-pentanediol, 1,6-hexanediol, neopentyl glycol, 3,3'-dimethylolheptane, 1,9-nonanediol, C such as 1,10-decanediol, 12-hydroxystearyl alcohol, hydrogenated dimer diol _2-40 Poly (oxy-C) such as alkane or aliphatic low molecular diol), polyoxyalkylene glycol (diethylene glycol, triethylene glycol, polyoxyethylene glycol, dipropylene glycol, polyoxypropylene glycol, polyoxytetramethylene glycol) _2-4 Alkylene) glycol or C _2-4 An alkylene oxide copolymer, etc.), an alkylene oxide adduct of bisphenol A or hydrogenated bisphenol A, a polyol (glycerin, trimethylolpropane, pentaerythritol, sorbitol, etc.), or a mixture thereof.
[0017]
Examples of the lactone include C such as ε-caprolactone, δ-valerolactone, and β-methyl-δ-valerolactone. _3-14 Examples include lactones.
[0018]
Polyether polyols include alkylene oxides (e.g., ethylene oxide, propylene oxide, butylene oxide, tetrahydrofuran, 3-methyltetrahydrofuran, oxetane compounds such as C). _2-5 Homopolymers or copolymers of (alkylene oxide).
[0019]
The polycarbonate polyol includes at least one selected from the above polyhydric alcohol, the above polyester polyol, the above polyether polyol, and a short chain dialkyl carbonate (for example, di-C such as dimethyl carbonate, diethyl carbonate, etc.). _1-4 And polycarbonate diols obtained by reaction with alkyl carbonates).
[0020]
The polyurethane polyol can be obtained by reacting at least one selected from the polyhydric alcohol, the polyester polyol, the polyether polyol, the polycarbonate polyol and the like with a polyisocyanate.
[0021]
Examples of the polyisocyanate include polyisocyanate monomers and derivatives thereof that are usually used in the production of polyurethane.
[0022]
Examples of the polyisocyanate monomer include aromatic diisocyanate, araliphatic diisocyanate, alicyclic diisocyanate, and aliphatic diisocyanate.
[0023]
Examples of the aromatic diisocyanate include m- or p-phenylene diisocyanate or a mixture thereof, 4,4'-diphenyl diisocyanate, 1,5-naphthalene diisocyanate (NDI), 4,4'-, 2,4'- or 2 2,2'-diphenylmethane diisocyanate or mixtures thereof (MDI), 2,4- or 2,6-tolylene diisocyanate or mixtures thereof (TDI), 4,4'-toluidine diisocyanate (TODI), 4,4'-diphenyl ether diisocyanate Etc. can be exemplified.
[0024]
Examples of the araliphatic diisocyanate include 1,3- or 1,4-xylylene diisocyanate or a mixture thereof (XDI), 1,3- or 1,4-tetramethylxylylene diisocyanate or a mixture thereof (TMXDI), ω , Ω′-diisocyanate-1,4-diethylbenzene and the like.
[0025]
Examples of the alicyclic diisocyanate include 1,3-cyclopentene diisocyanate, 1,4-cyclohexane diisocyanate, 1,3-cyclohexane diisocyanate, 3-isocyanate methyl-3,5,5-trimethylcyclohexyl isocyanate (isophorone diisocyanate; IPDI). 4,4'-, 2,4'- or 2,2'-dicyclohexylmethane diisocyanate or mixtures thereof (hydrogenated MDI), methyl-2,4-cyclohexanediisocyanate, methyl-2,6-cyclohexanediisocyanate, 1, Examples thereof include 3- or 1,4-bis (isocyanatomethyl) cyclohexane or a mixture thereof (hydrogenated XDI).
[0026]
Examples of the aliphatic diisocyanate include trimethylene diisocyanate, tetramethylene diisocyanate, hexamethylene diisocyanate (HDI), pentamethylene diisocyanate, 1,2-, 2,3- or 1,3-butylene diisocyanate, 2,4,4- Alternatively, 2,2,4-trimethylhexamethylene diisocyanate and the like can be exemplified.
[0027]
Examples of the polyisocyanate monomer derivatives include multimers (dimers, trimers, etc.) of the above polyisocyanate monomers, modified multimers (modified dimers, modified trimers). Etc.), for example, a biuret modified product produced by reaction of the polyisocyanate monomer with water, an allophanate modified product produced by reaction with a polyhydric alcohol, oxadia produced by reaction with carbon dioxide gas, etc. A gintrione etc. can be illustrated.
[0028]
In addition, when a component (A) is a polyurethane polyol, the terminal hydroxy polyurethane whose equivalent ratio (NCO / OH) of the isocyanate group of the polyisocyanate component with respect to the hydroxyl group of a polyol component is less than 1 can be used.
[0029]
Among these polyols, polyester polyols, particularly, aromatic dicarboxylic acids (for example, isophthalic acid, terephthalic acid or their alkyl esters) and aliphatic dicarboxylic acids (for example, adipic acid, sebacic acid, azelaic acid, etc.) At least one polybasic acid selected from the group (especially a polybasic acid combining an aromatic dicarboxylic acid and an aliphatic dicarboxylic acid) and a polyhydric alcohol (for example, ethylene glycol, diethylene glycol, 1,4-butanediol, Polyester polyols obtained from 1,3-butanediol, neopentyl glycol, 1,6-hexanediol and the like are preferred.
[0030]
These components (A) can be used alone or in combination of two or more. The number average molecular weight of the component (A) is 800 or more (for example, 800 to 5000), preferably about 800 to 3000 (for example, 850 to 2000). When the number average molecular weight is less than 800, the adhesive component passes through the pinhole of the metal foil, and blocking tends to occur in the first laminate. In particular, when the viscosity of the component (B) at 25 ° C. is less than 20000 mPa · s, the number average molecular weight of the component (A) is preferably 800 or more. On the other hand, when the number average molecular weight exceeds 5000, the viscosity becomes too high, and coating may be difficult.
[0031]
[(B) Polyisocyanate component]
The (B) polyisocyanate component is not particularly limited as long as it has a plurality of isocyanate groups at the terminal and the viscosity at 80 ° C. immediately after mixing the component (A) and the component (B) is 900 mPa · s or more. . Among them, a derivative of at least one diisocyanate selected from the group consisting of araliphatic diisocyanates (for example, XDI), alicyclic diisocyanates (for example, IPDI) and aliphatic diisocyanates (for example, HDI) (for example, Dimer, trimer, trimer obtained by modifying or reacting a part of NCO group with monool or polyol, modified biuret, modified allophanate, in particular, part of NCO group is monool (for example, t- C such as butanol _1-6 A component containing a trimer or biuret modified by modification or reaction with an alcohol) or a polyol (for example, a polyol such as alkanediol or polyoxyalkylene glycol) is preferred. Furthermore, the component (B) is a reaction product of a terminal isocyanate group-containing oligomer (at least one selected from the above polyhydric alcohol, the above polyester polyester, the above polyether polyol, the above polycarbonate polyol, the above polyurethane polyol, etc.) and a polyisocyanate. Etc.), in particular, it may contain a reaction product of a polyester polyol and a polyisocyanate.
[0032]
In addition, the said terminal isocyanate group containing oligomer should just have the equivalent ratio (NCO / OH) of the isocyanate group of the polyisocyanate component with respect to the hydroxyl group of a polyol component exceeding 1, Preferably it is 1.5-3, More preferably, it is 1.7. What is necessary is just about ~ 3 (for example, 2 to 2.5).
[0033]
A component (B) can be used individually or in combination of 2 or more types. The viscosity of the component (B) at 25 ° C. is 20000 mPa · s or more (for example, 20000 to 1000000 mPa · s), preferably about 20000 to 500000 mPa · s. When the viscosity at 25 ° C. of the component (B) is less than 20000 mPa · s, the adhesive component passes through the pinhole of the metal foil, and blocking tends to occur in the first laminate. In particular, when the number average molecular weight of the component (A) is less than 800, the viscosity of the component (B) at 25 ° C. is preferably 20000 mPa · s or more, and the number average molecular weight of the component (A) is less than 800. Even if it exists, blocking can be prevented effectively. On the other hand, if the viscosity exceeds 1,000,000 mPa · s, coating may be difficult.
[0034]
In the present invention, the number average molecular weight of the component (A) may be 800 or more, or the viscosity of the component (B) at 25 ° C. may be 20000 mPa · s or more, but the number average molecular weight of the component (A) is It is preferable that the viscosity of the component (B) at 25 ° C. is 800 or more and 20000 mPa · s or more.
[0035]
By blending the component (A) and the component (B), the solvent-free two-component curable laminate adhesive of the present invention can be obtained. The mixing ratio of the component (A) and the component (B) is such that the equivalent ratio (NCO / OH) of the isocyanate group of the component (B) to the hydroxyl group of the component (A) is 0.4 to 10, preferably 0.5. Can be selected from a range of about ˜5, particularly about 0.6˜2.5.
[0036]
[Additive]
If necessary, an additive may be added to the adhesive composition of the present invention. Examples of additives include coupling agents (silane coupling agents, titanium coupling agents, particularly silane coupling agents), phosphorus oxygen acids (orthophosphoric acid, metaphosphoric acid, polyphosphoric acid, etc.) or derivatives thereof, epoxy resins, and the like. The at least 1 type of adhesive improvement agent selected from these can be illustrated. The silane coupling agent has at least an alkoxysilyl group (particularly C _1-2 An alkoxysilyl group) and a functional group such as an isocyanate group, a polymerizable group (for example, a vinyl group, a (meth) acryloyl group), a glycidyl group, an N-substituted amino group, a carboxyl group, a mercapto group. May be. Epoxy resins include glycidyl ether type epoxy resins (bisphenol A type, F type, AD type bisphenol type epoxy resins, bromine-containing epoxy resins, phenol and cresol type epoxy resins, etc.), cyclic aliphatic epoxy resins, glycidyl ester types. An epoxy resin, a glycidylamine type epoxy resin, a heterocyclic epoxy resin, etc. can be illustrated, and a bisphenol type epoxy resin (especially a bisphenol A type epoxy resin) is usually used. The number average molecular weight of such an additive is usually 700 or less, preferably about 80 to 600 (for example, 100 to 600).
[0037]
In addition, as additives, catalysts for adjusting the curing reaction, coating property improvers, leveling agents, antifoaming agents, stabilizers such as antioxidants and UV absorbers, plasticizers, surfactants, color pigments, Organic or inorganic fine particles may be added.
[0038]
These additives can be contained in a proportion of about 0.001 to 5 parts by weight, preferably about 0.01 to 5 parts by weight with respect to 100 parts by weight of component (A). If the amount of the additive used (especially the total amount) is less than 0.001 part by weight, the effect of the additive is difficult to appear. If the amount exceeds 5 parts by weight, the additive is taken down by the additive when the molecular weight is low. The adhesive passes through the pinhole of the metal foil, and blocking is likely to occur in the first lami.
[0039]
[Solvent-free two-component curing adhesive composition]
The solvent-free two-component curable laminate adhesive composition of the present invention obtained by blending the above components can be used for laminating a metal foil and a plastic film with an ordinary solvent-free laminator.
[0040]
The viscosity at 80 ° C. immediately after mixing the component (A) and the component (B) is 900 mPa · s or more (900 to 10000 mPa · s), preferably 900 to 5000 mPa · s, more preferably about 900 to 3000 mPa · s. Range. If the viscosity is too low, the initial cohesive force is weak and may cause delaminating. If the viscosity is too high, coating may be difficult and appearance may be deteriorated. In the present invention, “immediately after mixing” means within 5 minutes after uniform mixing.
[0041]
[Lamination method]
The adhesive composition of the present invention is useful for laminating a metal foil and a plastic film. Examples of the metal foil include a spreadable metal foil (aluminum foil, gold foil, etc.). The thickness of the metal foil is about 5 to 100 μm, preferably about 5 to 20 μm, more preferably about 5 to 15 μm (particularly about 5 to 10 μm).
[0042]
Examples of the plastic film include olefin polymers (for example, polyethylene and polypropylene), polyester polymers (for example, polyalkylene terephthalates such as polyethylene terephthalate and polybutylene terephthalate, polyalkylene naphthalates, and polyalkylene arylates thereof. Copolyesters having units as main components), polyamide polymers (for example, nylon 6, nylon 66, etc.), vinyl polymers (for example, polyvinyl chloride, ethylene-vinyl acetate copolymer, ethylene-vinyl alcohol copolymer) A film composed of a polymer or the like). These plastic films may be unstretched films (unstretched polyethylene, polypropylene, etc.) or uniaxial or biaxially stretched films (biaxially stretched polypropylene, polyalkylene terephthalate, nylon, etc.). Further, as the plastic film, various coextruded films and a laminated composite film in which the plastic films are bonded together with another adhesive may be used. The thickness of the plastic film is usually about 5 to 200 μm. The surface of the plastic film (the coated or non-coated surface of the adhesive composition) may be subjected to a surface treatment such as a corona discharge treatment, or a primer layer such as an anchor coating agent may be formed. The plastic film may be printed.
[0043]
Lamination may be performed by laminating a plastic film on at least one surface of the metal foil, or laminating (by secondary lamination) on both surfaces. Usually, after compounding with a first lami, the film is wound on a take-up roll and cured if necessary, and then the composite film is unwound from the roll and second-laminated, wound on the take-up roll, and cured if necessary. In the first laminate, an adhesive composition is usually applied to a plastic film and bonded to a metal foil such as an aluminum foil. In addition, by the time of the second lamination, this laminated composite film may be heated and cured (for example, cured at 25 to 60 ° C.) in order to cure the adhesive. May be performed. Although blocking tends to occur when heated and cured, the adhesive composition of the present invention does not generate blocking even when heated and cured after the end of the first lamination. In addition, what is necessary is just to use the adhesive composition of this invention at least in the 1st lamination process, and the adhesives after the 2nd lamination can use not only a solvent-free type | system | group but solvent-type, water-type other adhesives for lamination.
[0044]
When laminating the adhesive composition (at the time of coating), the adhesive composition is heated within a range of about 50 to 100 ° C. (preferably 50 to 90 ° C., more preferably 50 to 80 ° C.). It is preferable to make the viscosity as high as possible. The appropriate viscosity is about 100 to 5000 mPa · s, preferably about 300 to 3000 mPa · s at a predetermined temperature in the above range. In addition, when the heating exceeds 100 ° C., heat is generated due to the reaction of the components (A) and (B) before coating, and the viscosity increases at an accelerated rate, so that the appearance of the laminated composite film is deteriorated. There is.
[0045]
In addition, the application amount of the adhesive composition of the present invention is 0.5 to 5 g / m in each lamination step. ² , Preferably 1 to 3 g / m ² More preferably, 1.5-2 g / m ² Degree. Application amount is 0.5g / m ² If the amount is less than 1, the adhesiveness is not sufficiently exhibited, and the appearance may be deteriorated, and the coating amount is 5 g / m. ² Exceeding this may cause the adhesive to leak out from the end of the film, which may hinder the production of the laminated composite film.
[0046]
【The invention's effect】
In the present invention, even when a laminated composite film containing a metal foil such as an aluminum foil having a small thickness is produced using a solvent-free two-component curing adhesive, blocking occurs due to leakage of the adhesive from the metal foil. Can be effectively prevented.
[0047]
【Example】
Hereinafter, the present invention will be described in more detail based on examples, but the present invention is not limited to these examples.
[0048]
[Production Example 1]
291.56 g of dimethyl terephthalate, 748.32 g of isophthalic acid, 368.22 g of ethylene glycol, 100.01 g of neopentyl glycol, 340.43 g of 1,6-hexanediol, and 0.18 g of zinc acetate were charged into the reactor, respectively, under a nitrogen stream. The esterification reaction was performed at 180 to 220 ° C. After distilling a predetermined amount of water and methanol, 282.61 g of azelaic acid was added, and esterification was performed at 180 to 220 ° C. to obtain a polyester polyol a having a number average molecular weight of about 900.
[0049]
[Production Example 2]
272.1 g of dimethyl terephthalate, 698.64 g of isophthalic acid, 329.55 g of ethylene glycol, 89.51 g of neopentyl glycol, 304.68 g of 1,6-hexanediol, and 0.165 g of zinc acetate were charged into the reactor, respectively, under a nitrogen stream. The esterification reaction was performed at 180 to 220 ° C. After distilling a predetermined amount of water and methanol, 263.85 g of azelaic acid was added and an esterification reaction was performed at 180 to 220 ° C. to obtain a polyester polyol b having a number average molecular weight of about 1100.
[0050]
[Production Example 3]
199.32 g of dimethyl terephthalate, 511.57 g of isophthalic acid, 237.5 g of ethylene glycol, 64.5 g of neopentyl glycol, 219.57 g of 1,6-hexanediol, and 0.12 g of zinc acetate were charged into the reactor, respectively, under a nitrogen stream. The esterification reaction was performed at 180 to 220 ° C. After distilling a predetermined amount of water and methanol, 193.2 g of azelaic acid was added and an esterification reaction was performed at 180 to 220 ° C. to obtain a polyester polyol c having a number average molecular weight of about 1200.
[0051]
[Production Example 4]
A reactor was charged with 223.19 g of dimethyl terephthalate, 572.84 g of isophthalic acid, 338.77 g of ethylene glycol, 92.01 g of neopentyl glycol, 313.2 g of 1,6-hexanediol, and 0.15 g of zinc acetate. The esterification reaction was performed at 180 to 220 ° C. After distilling a predetermined amount of water and methanol, 216.34 g of azelaic acid was added and an esterification reaction was performed at 180 to 220 ° C. to obtain a polyester polyol d having a number average molecular weight of about 500.
[0052]
[Production Example 5]
The reactor was charged with 720.68 g of isophthalic acid, 193.96 g of ethylene glycol, 262.28 g of neopentyl glycol, 378.76 g of 1,6-hexanediol, 150.14 g of diethylene glycol, and 0.18 g of zinc acetate, respectively, and 180 ° under nitrogen flow. The esterification reaction was performed at ˜220 ° C. After distilling a predetermined amount of water, 326.6 g of azelaic acid was added and an esterification reaction was performed at 180 to 220 ° C. to obtain a polyester polyol e having a number average molecular weight of about 450.
[0053]
[Production Example 6]
292.5 g of polyester polyol e obtained in Production Example 5 and 122.21 g of xylylene diisocyanate were charged into a reactor, respectively, and a urethanization reaction was performed at 70 to 80 ° C. in a nitrogen stream. Thereafter, unreacted xylylene diisocyanate was removed by Smith distillation to obtain polyisocyanate f having a viscosity of 470000 mPa · s at 25 ° C.
[0054]
[Production Example 7]
325 g of polyester polyol d obtained in Production Example 4 and 1223.21 g of xylylene diisocyanate were charged into a reactor, and urethanization reaction was performed at 70 to 80 ° C. under a nitrogen stream. Thereafter, unreacted xylylene diisocyanate was removed by Smith distillation to obtain polyisocyanate g having a viscosity of 730000 mPa · s at 25 ° C.
[0055]
[Production Example 8]
Polyisocyanate f500 g obtained in Production Example 6 and 500 g of a polyisocyanate component (Takeda D-177N, Takeda Pharmaceutical Co., Ltd., a modified product of an aliphatic polyisocyanate trimer) were added at 50 ° C. in a nitrogen atmosphere. And a polyisocyanate component A having a viscosity of 7500 mPa · s at 25 ° C. was obtained.
[0056]
[Production Example 9]
Polyisocyanate f600 g obtained in Production Example 6 and 300 g of a polyisocyanate component (Takeda D-177N, Takeda Pharmaceutical Co., Ltd., a modified product of a trimer of aliphatic polyisocyanate) at 50 ° C. in a nitrogen atmosphere. To obtain a polyisocyanate component B having a viscosity of 32,500 mPa · s at 25 ° C.
[0057]
[Production Example 10]
The polyisocyanate f 750 g obtained in Production Example 6 and 250 g of a polyisocyanate component (Takeda D-177N, Takeda Pharmaceutical Co., Ltd., a modified product of an aliphatic polyisocyanate trimer) were added at 50 ° C. in a nitrogen atmosphere. And a polyisocyanate component C having a viscosity of 68300 mPa · s at 25 ° C. was obtained.
[0058]
[Production Example 11]
The polyisocyanate g 750 g obtained in Production Example 7 and 250 g of a polyisocyanate component (Takeda D-170N, Takeda Pharmaceutical Co., Ltd., Takeda Pharmaceutical Co., Ltd.), which is a modified product of an aliphatic polyisocyanate trimer, were added at 50 ° C. in a nitrogen atmosphere. And a polyisocyanate component D having a viscosity of 100000 mPa · s at 25 ° C. was obtained.
[0059]
[Production Example 12]
750 g of a biuret-modified aromatic aliphatic polyisocyanate produced by removing solvent from Takenate A-14 (manufactured by Takeda Pharmaceutical Co., Ltd.) and a polyisocyanate component which is a modified trimer of aliphatic polyisocyanate (trimer) Takeda Pharmaceutical Co., Ltd., Takenate D-177N) (250 g) was uniformly mixed at 50 ° C. in a nitrogen atmosphere to obtain a polyisocyanate component E having a viscosity of 25000 mPa · s at 25 ° C.
[0060]
[Examples and Comparative Examples]
The polyester polyols a to c obtained in the above production examples, the polyisocyanate components A to E, and the following various additives were blended as shown in Table 1 to prepare a laminating adhesive. Next, using the obtained adhesive for laminating, a composite film was produced by the following method, and each composite film was evaluated for blocking by the following method. The results are shown in Table 2.
[0061]
[Various additives]
Silane coupling agent: Shin-Etsu Chemical Co., Ltd., KBE-403
Silane coupling agent: Shin-Etsu Chemical Co., Ltd., KBE-603
・ Phosphoric acid: Wako Pure Chemical Industries, Ltd.
[0062]
[Polyol component used in Comparative Example]
・ Polyol component: Takeda Pharmaceutical Co., Ltd., Takelac A-660
Polyol component: Takelac A-658, manufactured by Takeda Pharmaceutical Company Limited.
[0063]
[Polyisocyanate component used in comparative example]
・ Polyisocyanate component: Takenate A-70HN, manufactured by Takeda Pharmaceutical Company Limited
Polyisocyanate component: Takenate A-65 manufactured by Takeda Pharmaceutical Company Limited.
[0064]
[Production of composite film]
The coating amount of the adhesives for laminating examples and comparative examples on a nylon film with a solventless laminator is 1.5-2 g / m. ² It apply | coated so that it might become, and it bonded together with aluminum foil. Thereafter, the rolls of these bonded films were cured at 40 ° C. for 1 day to prepare a composite film consisting of two layers of nylon film (thickness 15 μm) / aluminum foil (7 μm).
[0065]
[Evaluation of blocking]
The produced composite film roll was rewound by 50 m by a machine and evaluated according to the following criteria depending on whether or not peeling sound was generated when the roll was rewound.
[0066]
○: No sound
×: Sound is generated
[0067]
[Table 1]

[0068]
[Table 2]

Claims (10)

It contains a polyol component (A) and a polyisocyanate component (B) containing a trimer of aliphatic diisocyanate or a modified product thereof , and the viscosity at 80 ° C. immediately after mixing the component (A) and the component (B) is 900 mPa A solvent-free two-component curable adhesive composition that is at least s.   The composition according to claim 1, wherein the number average molecular weight of the component (A) is 800 or more.   The composition according to claim 1, wherein the viscosity of component (B) at 25 ° C is 20000 mPa · s or more. Component (B), have a plurality of isocyanate groups to end end The composition of claim 1 wherein further comprising the following component (B1).
(B1) Reaction product of polyisocyanate with at least one selected from polyhydric alcohol, polyester polyol, polyether polyol, polycarbonate polyol and polyurethane polyol   The composition according to claim 1, wherein the equivalent ratio (NCO / OH) of the isocyanate group of the component (B) to the hydroxyl group of the component (A) is 0.4 to 10. Polyol component obtained from at least one polybasic acid selected from the group consisting of an aromatic dicarboxylic acid and an aliphatic dicarboxylic acid and a polyhydric alcohol, and having a number average molecular weight of 800-5000 (polyol component) A composition comprising A) and a polyisocyanate component (B) containing an aliphatic diisocyanate trimer or a modified product thereof and having a viscosity at 25 ° C. of 20,000 to 1,000,000 mPa · s. ) Of the isocyanate group of the component (B) to the hydroxyl group (NCO / OH) is 0.5 to 5 and at 80 ° C. within 5 minutes after mixing the component (A) and the component (B). A solvent-free two-component curable adhesive composition having a viscosity of 900 to 5000 mPa · s.   The composition according to claim 1 for laminating a metal foil having a thickness of 5 to 15 µm and a plastic film.   The composition of claim 1 further comprising an adhesion improver.   The composition according to claim 8, wherein the adhesion improver is at least one selected from the group consisting of a coupling agent, phosphorus oxyacid, and an epoxy resin.   A method of laminating a metal foil and a plastic film using the composition according to claim 1.