JP2023516834A - Adhesives, laminates, packaging materials - Google Patents

Abstract

To provide a solvent-free adhesive having a large initial cohesive force and suitable for solvent-free lamination. A polyisocyanate composition (A) and a polyol composition (B), wherein the polyol composition (B) comprises a crystalline polyester polyol (B1) having a melting point of 50° C. or higher and 70° C. or lower, and an average number of functional groups is 2.01 or more and 2.2 or less, and the amount of the polyester polyol (B1) in the total amount of the polyester polyol (B1) and the polyester polyol (B2) is 15 mass. % or more and 85% by mass or less and a polyester polyol (B2) content of 15% by mass or more and 85% by mass or less, a laminate and a packaging material obtained by using the same.

Description

TECHNICAL FIELD The present invention relates to an adhesive, a laminate obtained using the adhesive, a method for producing the laminate, and a packaging material.

Laminated films (sometimes called laminated films) used for various packaging materials, labels, etc. are laminated with a wide variety of plastic films, metal foils, papers, etc. to improve design, functionality, storage stability, convenience, Transportability is imparted, and in particular, packages formed by molding the laminated film into bags are used as packages for foods, medicines, detergents, and the like.

Conventional laminated film is coated with a two-component curing type adhesive in which a polyisocyanate compound and a polyol compound are dissolved in a volatile organic solvent. Most of them were obtained by a dry lamination method. However, in recent years, from the viewpoint of reducing the environmental load and improving the working environment, attention has been focused on two-component curing solvent-free adhesives in which polyisocyanate compounds and polyol compounds do not contain volatile organic solvents (patent Document 1, Patent Document 2).

JP 2014-159548 A Japanese Patent Application Laid-Open No. 2001-172602

Unlike solvent-based adhesives, polyisocyanate compounds and polyol compounds used in solvent-free adhesives must have a viscosity that allows coating without being diluted with an organic solvent, and their molecular weight is inevitably low. I have to. However, if the molecular weight of the polyisocyanate compound or polyol compound is reduced, the initial cohesive force will also become smaller, resulting in tunnel-like delamination from the edge of the laminate film (tunneling) and the adhesive surface of the wound laminate film slipping (winding slippage). ). It is conceivable to increase the molecular weight of the polyisocyanate compound and the polyol compound to some extent and apply them at a high temperature, but in this case the damage to the film increases.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a solvent-free adhesive which has a high initial cohesive force and is suitable for solvent-free lamination.

The present invention comprises a polyisocyanate composition (A) and a polyol composition (B), wherein the polyol composition (B) is a crystalline polyester polyol (B1) having a melting point of 50° C. or higher and 70° C. or lower. , and an amorphous polyester polyol (B2) having an average functional group number of 2.01 or more and 2.2 or less, and the blending of the polyester polyol (B1) in the total amount of the polyester polyol (B1) and the polyester polyol (B2) A two-component adhesive having an amount of 15% by mass or more and 85% by mass or less and a blending amount of polyester polyol (B2) of 15% by mass or more and 85% by mass or less, a laminate obtained using the same, and a packaging material. .

According to the present invention, it is possible to provide an adhesive that has a large initial cohesive force, suppresses tunneling and winding misalignment, and is suitable for solvent-free lamination.

<Adhesive>
The adhesive of the present invention is a two-component adhesive containing a polyisocyanate composition (A) and a polyol composition (B). The adhesive of the present invention will be described in detail below.

(Polyisocyanate composition (A))
The polyisocyanate composition (A) used in the adhesive of the present invention contains a polyisocyanate compound (A1). As the polyisocyanate compound (A1), conventionally known compounds can be used without particular limitation. Burettes, nurates, adducts, allophanates, carbodiimide-modified isocyanates, urethane prepolymers obtained by reacting polyisocyanates with polyols, and the like can be mentioned, and these can be used alone or in combination.

Examples of aromatic polyisocyanates include 2,2'-diphenylmethane diisocyanate, 2,4'-diphenylmethane diisocyanate, 4,4'-diphenylmethane diisocyanate, 1,3-phenylene diisocyanate, 4,4'-diphenyl diisocyanate, 1, 4-phenylene diisocyanate, 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, 4,4'-toluidine diisocyanate, 2,4,6-triisocyanatotoluene, 1,3,5-triisocyanatobenzene, diani Cydine diisocyanate, 4,4′-diphenylether diisocyanate, 4,4′,4″-triphenylmethane triisocyanate, and the like, but are not limited thereto.

The araliphatic polyisocyanate means an aliphatic isocyanate having one or more aromatic rings in the molecule, m- or p-xylylene diisocyanate, α, α, α', α'-tetramethyl xylylene diisocyanate etc., but not limited to these.

Aliphatic polyisocyanates include trimethylene diisocyanate, 1,2-propylene diisocyanate, tetramethylene diisocyanate, 1,3-butylene diisocyanate, 2,3-butylene diisocyanate, pentamethylene diisocyanate, hexamethylene diisocyanate, 2,4,4- Examples include, but are not limited to, trimethylhexamethylene diisocyanate, dodecamethylene diisocyanate, and the like.

Alicyclic polyisocyanates include isophorone diisocyanate, 1,3-cyclopentane diisocyanate, 1,3-cyclohexane diisocyanate, 1,4-cyclohexane diisocyanate, methyl-2,4-cyclohexane diisocyanate, and methyl-2,6-cyclohexane diisocyanate. , 4,4′-methylenebis(cyclohexylisocyanate), 1,4-bis(isocyanatomethyl)cyclohexane, and the like, but are not limited thereto.

Polyols used for synthesis of urethane prepolymers include, for example, ethylene glycol, propylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 3-methyl-1,5-pentanediol, Alkylene glycols such as 1,6-hexanediol, neopentyl glycol, methylpentanediol, dimethylbutanediol, butylethylpropanediol, 1,4-cyclohexanediol, 1,4-cyclohexanedimethanol;

Bisphenols such as bisphenol A, bisphenol F, hydrogenated bisphenol A, hydrogenated bisphenol F;
dimer diall;
bishydroxyethoxybenzene;
Polyalkylene glycols such as diethylene glycol, triethylene glycol, other polyethylene glycols, polypropylene glycol, polybutylene glycol;
Urethane bond-containing polyether polyol obtained by further polymerizing polyalkylene glycol with aromatic or aliphatic polyisocyanate;

Alkylene glycol or polyalkylene glycol and oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, fumaric acid, maleic acid, suberic acid, azelaic acid, sebacic acid, undecanedioic acid, dodecanedioic acid, tridecanedioic acid, etc. Obtained by reacting with at least one aromatic polyvalent carboxylic acid such as aliphatic dicarboxylic acid, orthophthalic acid, isophthalic acid, terephthalic acid, trimellitic acid, pyromellitic acid having a carbon atom number in the range of 2 to 13 a polyester polyol;
Polyester obtained by ring-opening polymerization reaction of cyclic ester compounds such as propiolactone, butyrolactone, ε-caprolactone, σ-valerolactone, β-methyl-σ-valerolactone, glycol, glycerin, trimethylolpropane, pentaerythritol, etc. and a polyester polyol which is a reaction product with a polyhydric alcohol.

(Polyol composition (B))
The polyol composition (B) used in the adhesive of the present invention comprises a crystalline polyester polyol (B1) having a melting point of 50° C. or higher and 70° C. or lower and an average functional group number of 2.01 or higher and 2.2 or lower. and an amorphous polyester polyol (B2).

(Polyester polyol (B1))
The polyester polyol (B1) has crystallinity and a melting point of 50° C. or higher and 70° C. or lower. In the present specification, having crystallinity means that the polyester polyol (B1) has a melting point and a heat of fusion of 0.1 J/g or more. When the melting point is less than 50°C, sufficient initial cohesive strength is difficult to develop, and when it exceeds 70°C, the coating suitability may deteriorate.

The melting point and heat of fusion of the polyester polyol (B1) are measured as follows.
Using a differential scanning calorimeter (DSC-7000 manufactured by SII Nanotechnology Co., Ltd., hereinafter referred to as DSC), 5 mg of a sample was heated from 30° C. to T ₁ ° C. at a rate of 10° C./min under a nitrogen stream of 20 mL/min. After heating, it is held for 10 minutes and then cooled to T2 _° C at 10°C/min to remove the heat history. After holding at T ₂ ° C. for 5 minutes, the temperature was again raised to T ₃ ° C. at 10 ° C./min to measure the DSC curve, and the maximum peak temperature of the endothermic curve observed in the second heating step was taken as the melting point. , the heat of fusion is calculated from the area of the portion surrounded by this maximum peak and baseline.

T ₂ < T ₃ ≤ T ₁ , T ₂ is sufficiently lower than the glass transition temperature of the crystalline polyester polyol (B1), and T ₁ and T ₃ are at least 30°C lower than the melting point of the crystalline polyester polyol (B1) or higher temperature. As an example, T ₁ is 200° C., T ₂ is -80° C., and T ₃ is 200° C., but these are appropriately adjusted according to the sample to be measured.

Polyester polyol (B1) is a reaction product of a monomer composition containing polyhydric carboxylic acid and polyhydric alcohol. Polyvalent carboxylic acids used in the synthesis of the polyester polyol (B1) include oxalic acid, malonic acid, succinic acid, succinic anhydride, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, and fumaric acid. , maleic acid, maleic anhydride, itaconic acid, aliphatic polybasic acids such as dimer acid;
Aliphatic polybasic acids such as dimethyl malonate, diethyl malonate, dimethyl succinate, dimethyl glutarate, dimethyl adipate, diethyl pimelate, diethyl sebacate, dimethyl fumarate, diethyl fumarate, dimethyl maleate, and diethyl maleate Alkyl ester of;

1,1-cyclopentanedicarboxylic acid, 1,2-cyclopentanedicarboxylic acid, 1,3-cyclopentanedicarboxylic acid, 1,2-cyclohexanedicarboxylic acid, 1,3-cyclohexanedicarboxylic acid, 1,4-cyclohexanedicarboxylic acid , tetrahydrophthalic anhydride, 4-methylhexahydrophthalic anhydride, hexahydrophthalic anhydride, cyclohexane-1,2,4-tricarboxylic acid-1,2-anhydride, hymic anhydride, hetic anhydride, etc. family polybasic acid;

orthophthalic acid, terephthalic acid, isophthalic acid, phthalic anhydride, 1,4-naphthalenedicarboxylic acid, 2,5-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, 2,3-naphthalenedicarboxylic anhydride, naphthalic acid, trimellitic acid, trimellitic anhydride, pyromellitic acid, pyromellitic anhydride, biphenyldicarboxylic acid, 1,2-bis(phenoxy)ethane-p,p'-dicarboxylic acid, benzophenonetetracarboxylic acid, benzophenonetetracarboxylic acid di aromatic polybasic acids such as anhydrides, 5-sodium sulfoisophthalic acid, tetrachlorophthalic anhydride, and tetrabromophthalic anhydride;
dimethyl terephthalic acid, methyl esters of aromatic polybasic acids such as dimethyl 2,6-naphthalenedicarboxylate;

From the group consisting of adipic acid, sebacic acid, dodecanedicarboxylic acid, terephthalic acid, isophthalic acid, orthophthalic acid, and phthalic anhydride, since it can increase the crystallinity of the polyester polyol (B1) and further improve the initial cohesive strength. It is preferable to use one or more selected polybasic acids.

The polyhydric alcohol may be a diol or a trifunctional or higher polyol, and examples of the diol include ethylene glycol, diethylene glycol, propylene glycol, 1,3-propanediol, 1,2,2-trimethyl-1,3-propanediol, 2,2-dimethyl-3-isopropyl-1,3-propanediol, 1,4-butanediol, 1,3-butanediol, 3-methyl-1,3-butanediol, 1,5-pentanediol, 3 -methyl 1,5-pentanediol, neopentyl glycol, 1,6-hexanediol, 1,4-bis(hydroxymethyl)cyclohexane, 2,2,4-trimethyl-1,3-pentanediol, dimer diol, etc. aliphatic diols;

Ether glycols such as polyoxyethylene glycol and polyoxypropylene glycol;
Modified poly(s) obtained by ring-opening polymerization of aliphatic diols with various cyclic ether bond-containing compounds such as ethylene oxide, propylene oxide, tetrahydrofuran, ethyl glycidyl ether, propyl glycidyl ether, butyl glycidyl ether, phenyl glycidyl ether, and allyl glycidyl ether. ether diol;

Lactone-based polyester polyols obtained by polycondensation reaction of aliphatic diols with various lactones such as lactanoids and ε-caprolactone;
Bisphenols such as bisphenol A and bisphenol F;
Alkylene oxide adducts of bisphenols obtained by adding ethylene oxide, propylene oxide, etc. to bisphenols such as bisphenol A and bisphenol F can be mentioned.

Tri- or higher functional polyols include aliphatic polyols such as trimethylolethane, trimethylolpropane, glycerin, hexanetriol, and pentaerythritol;
Modified polyols obtained by ring-opening polymerization of aliphatic polyols with various cyclic ether bond-containing compounds such as ethylene oxide, propylene oxide, tetrahydrofuran, ethyl glycidyl ether, propyl glycidyl ether, butyl glycidyl ether, phenyl glycidyl ether, and allyl glycidyl ether. ether polyols;
Examples include lactone-based polyester polyols obtained by polycondensation reaction of aliphatic polyols with various lactones such as ε-caprolactone.

One selected from the group consisting of ethylene glycol, propanediol, butanediol, neopentyl glycol, hexanediol, octanediol and decanediol, since it can enhance the crystallinity of the polyester polyol (B1) and further improve the initial cohesive strength. It is preferable to use the above compounds.

Although the number average molecular weight of the polyester polyol (B1) is not particularly limited, it is preferably 500 or more and 3,000 or less as an example. The number average molecular weight (Mn) in the present invention is a value measured by gel permeation chromatography (GPC) under the following conditions.

Measuring device; HLC-8320GPC manufactured by Tosoh Corporation
Column; TSKgel 4000HXL, TSKgel 3000HXL, TSKgel 2000HXL, TSKgel 1000HXL manufactured by Tosoh Corporation
Detector; RI (differential refractometer)
Data processing; Multi-station GPC-8020modelII manufactured by Tosoh Corporation
Measurement conditions; Column temperature 40°C
Solvent Tetrahydrofuran
Flow rate 0.35 ml/min Standard; Monodisperse polystyrene Sample; 0.2% by mass tetrahydrofuran solution in terms of resin solid content filtered through a microfilter (100 μl)

(Polyester polyol (B2))
The polyester polyol (B2) is an amorphous polyester polyol having an average functional group number of 2.01 or more and 2.2 or less. The average functional group number of the polyester polyol (B2) is a value obtained by weight-averaging the functional group numbers of the respective monomers used in the synthesis of the polyester polyol (B2). If the average number of functional groups is less than 2.01, the heat seal strength will decrease. If it exceeds 2.2, gelation tends to occur, and production difficulty increases.

The polyester polyol (B2) is a reaction product of a monomer composition containing a polycarboxylic acid and a polyhydric alcohol, and the monomer composition is trifunctional or more capable of reacting with at least one of the polyhydric carboxylic acid and the polyhydric alcohol. containing compounds of Tri- or higher-functional compounds include polyvalent carboxylic acids such as trimellitic acid, trimellitic anhydride, pyromellitic acid, pyromellitic anhydride, and trimeric acid, glycerin, trimethylolpropane, pentaerythritol, dipentaerythritol, and polyglycerin. , polyhydric alcohols such as sorbitol, and esters of tri- or more functional alcohols and monocarboxylic acids such as glycerin fatty acid esters. These can be used singly or in combination of two or more.

It is preferable to use a compound having a large number of functional groups (for example, a compound having 5 or more functional groups) such as dipentaerythritol, polyglycerin, or sorbitol as the tri- or higher functional compound, because the heat seal strength is improved.

As other polyhydric carboxylic acids and polyhydric alcohols used in the synthesis of the polyester polyol (B2), those similar to those used for the polyester polyol (B1) can be used. Although the number average molecular weight of the polyester polyol (B2) is not particularly limited, it is 500 or more and 5000 or less as an example.

In the adhesive of the present invention, the blending amount of the polyester polyol (B1) in the total amount of the polyester polyol (B1) and the polyester polyol (B2) is 15% by mass or more and 85% by mass or less, and the blending amount of the polyester polyol (B2) is 15% by mass or more and 85% by mass or less. As a result, an adhesive having an excellent balance between initial cohesive strength and heat seal strength can be obtained. It is preferable that the blending amount of the polyester polyol (B1) in the total amount is 45% by mass or more and 85% by mass or less, and the blending amount of the polyester polyol (B2) is 15% by mass or more and 55% by mass or less, because the initial cohesive strength is high.

(Other polyols (B3))
The polyol composition (B) may contain a polyol (B3) other than the polyester polyol (B1) and the polyester polyol (B2). Examples of such polyols (B3) include ethylene glycol, propylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 3-methyl-1,5-pentanediol, 1, 6-hexanediol, neopentyl glycol, methylpentanediol, dimethylbutanediol, butylethylpropanediol, diethylene glycol, triethylene glycol, tetraethylene glycol, dipropylene glycol, tripropylene glycol, bishydroxyethoxybenzene, 1,4-cyclohexane Glycols such as diols, 1,4-cyclohexanedimethanol, triethylene glycol;

trifunctional or tetrafunctional aliphatic alcohols such as glycerin, trimethylolpropane, pentaerythritol;
bisphenols such as bisphenol A, bisphenol F, hydrogenated bisphenol A, and hydrogenated bisphenol F; dimer diol;
Polyether polyols obtained by addition polymerization of alkylene oxides such as ethylene oxide, propylene oxide, butylene oxide, styrene oxide, epichlorohydrin, tetrahydrofuran, and cyclohexylene in the presence of polymerization initiators such as glycols and trifunctional or tetrafunctional aliphatic alcohols. ;
A polyether urethane polyol obtained by further increasing the molecular weight of a polyether polyol with the aromatic or aliphatic polyisocyanate;
Castor oil, dehydrated castor oil, hydrogenated castor oil which is a hydrogenated castor oil, castor oil-based polyols such as adducts of 5 to 50 mol of alkylene oxide of castor oil, various vegetable oils, and mixtures thereof.

The blending amount of the polyol (B3) is not particularly limited, but is, for example, 40% by mass or less of the total amount of the polyester polyol (B1), the polyester polyol (B2), and the polyol (B3).

The polyisocyanate composition (A) and the polyol composition (B) are the ratio of the number of moles [NCO] of isocyanate groups contained in the polyisocyanate composition to the number of moles [OH] of hydroxyl groups contained in the polyol composition. [NCO]/[OH] is preferably blended in the range of 1.0 to 3.0.

(Other components of adhesive)
The adhesive of the present invention may contain components other than the polyisocyanate composition (A) and the polyol composition (B). Specifically, catalysts, acid group-containing compounds, adhesion promoters, pigments, plasticizers, leveling agents, inorganic fine particles such as colloidal silica and alumina sol, polymethyl methacrylate organic fine particles, defoaming agents, anti-sagging agents. , wetting and dispersing agents, viscosity modifiers, ultraviolet absorbers, metal deactivators, peroxide decomposers, flame retardants, reinforcing agents, plasticizers, lubricants, rust inhibitors, fluorescent brighteners, inorganic heat rays Absorbents, flame retardants, antistatic agents, dehydrating agents, known and commonly used thermoplastic elastomers, tackifiers, phosphoric compounds, melamine resins, reactive elastomers and the like may also be included. It may be contained in either or both of the polyisocyanate composition (A) and the polyol composition (B), or may be prepared separately from these and added to the polyisocyanate composition (A ), may be used by mixing with the polyol composition (B). Each component will be described below.

(catalyst)
The adhesive of the present invention can accelerate the curing reaction by using a catalyst as necessary. The catalyst is not particularly limited as long as it promotes the urethanization reaction between the polyisocyanate composition (A) and the polyol composition (B), and includes metal catalysts, amine catalysts, aliphatic cyclic amide compounds, and titanium chelates. Complexes and the like are exemplified.

Metal-based catalysts include metal complex-based, inorganic metal-based, and organic metal-based catalysts. As the metal complex catalyst, a group consisting of Fe (iron), Mn (manganese), Cu (copper), Zr (zirconium), Th (thorium), Ti (titanium), Al (aluminum), Co (cobalt) Examples include acetylacetonate salts of metals selected from the above, such as iron acetylacetonate, manganese acetylacetonate, copper acetylacetonate, zirconia acetylacetonate and the like. From the point of view of toxicity and catalytic activity, iron acetylacetonate (Fe(acac) ₃ ) or manganese acetylacetonate (Mn(acac) ₂ ) are preferred.

Examples of inorganic metal catalysts include those selected from Sn, Fe, Mn, Cu, Zr, Th, Ti, Al, Co, and the like.

Organometallic catalysts include organozinc compounds such as zinc octylate, zinc neodecanoate, and zinc naphthenate; , dioctyltin dilaurate, dibutyltin oxide, dibutyltin dichloride and other organic tin compounds, nickel octylate, nickel naphthenate and other organic nickel compounds, cobalt octylate, cobalt naphthenate and other organic cobalt compounds, bismuth octylate, neodecanoic acid Examples include organic bismuth compounds such as bismuth and bismuth naphthenate, and titanium compounds such as tetraisopropyloxytitanate, dibutyltitanium dichloride, tetrabutyltitanate and butoxytitanium trichloride.

Amine catalysts include triethylenediamine, 2-methyltriethylenediamine, quinuclidine, 2-methylquinuclidine, N,N,N',N'-tetramethylethylenediamine, N,N,N',N'-tetramethyl Propylenediamine, N,N,N',N'',N''-pentamethyldiethylenetriamine, N,N,N',N'',N''-pentamethyl-(3-aminopropyl)ethylenediamine, N,N,N', N″,N″-pentamethyldipropylenetriamine, N,N,N′,N′-tetramethylhexamethylenediamine, bis(2-dimethylaminoethyl)ether, dimethylethanolamine, dimethylisopropanolamine, dimethylaminoethoxyethanol , N,N-dimethyl-N'-(2-hydroxyethyl)ethylenediamine, N,N-dimethyl-N'-(2-hydroxyethyl)propanediamine, bis(dimethylaminopropyl)amine, bis(dimethylaminopropyl) isopropanolamine, 3-quinuclidinol, N,N,N',N'-tetramethylguanidine, 1,3,5-tris(N,N-dimethylaminopropyl)hexahydro-S-triazine, 1,8-diazabicyclo[5 .4.0]undecene-7, N-methyl-N′-(2-dimethylaminoethyl)piperazine, N,N′-dimethylpiperazine, dimethylcyclohexylamine, N-methylmorpholine, N-ethylmorpholine, 1-methyl imidazole, 1,2-dimethylimidazole, 1-isobutyl-2-methylimidazole, 1-dimethylaminopropylimidazole, N,N-dimethylhexanolamine, N-methyl-N'-(2-hydroxyethyl)piperazine, 1- (2-hydroxyethyl)imidazole, 1-(2-hydroxypropyl)imidazole, 1-(2-hydroxyethyl)-2-methylimidazole, 1-(2-hydroxypropyl)-2-methylimidazole and the like.

Aliphatic cyclic amide compounds include, for example, δ-valerolactam, ε-caprolactam, ω-enanthollactam, η-capryllactam, β-propiolactam and the like. Among these, ε-caprolactam is more effective in accelerating hardening.

The titanium chelate complex is a compound whose catalytic activity is enhanced by irradiation with ultraviolet rays, and a titanium chelate complex having an aliphatic or aromatic diketone as a ligand is preferable from the viewpoint of excellent curing acceleration effect. Further, in the present invention, in addition to aromatic or aliphatic diketones, those having alcohols having 2 to 10 carbon atoms as ligands are preferred from the viewpoint that the effects of the present invention are more pronounced.

These catalysts can be used alone or in combination of two or more. The amount of the catalyst compounded is preferably 0.001 to 3 parts by mass, more preferably 0.01 to 2 parts by mass, per 100 parts by mass of the total solid content of the polyisocyanate composition (A) and the polyol composition (B). is more preferable.

(acid group-containing compound)
The acid group-containing compound includes cyclic aliphatic acid anhydrides, aromatic acid anhydrides, unsaturated carboxylic acid anhydrides, and the like, and can be used singly or in combination of two or more. More specifically, for example, phthalic anhydride, trimellitic anhydride, pyromellitic anhydride, benzophenonetetracarboxylic anhydride, dodecenylsuccinic anhydride, polyadipic anhydride, polyazelaic anhydride, polysebacic acid Anhydride, poly(ethyloctadecanedioic anhydride), poly(phenylhexadecanedioic anhydride), tetrahydrophthalic anhydride, methyltetrahydrophthalic anhydride, methylhexahydrophthalic anhydride, hexahydrophthalic anhydride , methylhimic acid anhydride, trialkyltetrahydrophthalic anhydride, methylcyclohexene dicarboxylic acid anhydride, methylcyclohexene tetracarboxylic acid anhydride, ethylene glycol bistrimellitate dianhydride, het acid anhydride, nadic acid anhydride, methyl nadic anhydride, 5-(2,5-dioxotetrahydro-3-furanyl)-3-methyl-3-cyclohexane-1,2-dicarboxylic anhydride, 3,4-dicarboxy-1,2, 3,4-tetrahydro-1-naphthalenesuccinic dianhydride, 1-methyl-dicarboxy-1,2,3,4-tetrahydro-1-naphthalenesuccinic dianhydride and the like.

As the acid anhydride, the above-described compound modified with glycol may be used. Glycols that can be used for modification include alkylene glycols such as ethylene glycol, propylene glycol and neopentyl glycol; and polyether glycols such as polyethylene glycol, polypropylene glycol and polytetramethylene ether glycol. Furthermore, two or more of these glycols and/or copolymerized polyether glycols of polyether glycols can also be used.

A copolymer of a carboxylic acid having an unsaturated double bond and an aromatic vinyl compound may be used as the acid group-containing compound. Carboxylic acids having unsaturated double bonds include, for example, maleic anhydride. Examples of aromatic vinyl compounds include styrene, α-methylstyrene, divinylbenzene and the like.

The amount of the acid group-containing compound to be blended can be appropriately adjusted according to the purpose, but as an example, it is 0.1% by mass or more and 10% by mass or less of the solid content mass of the polyol composition (B).

(adhesion promoter)
Examples of adhesion promoters include coupling agents such as silane coupling agents, titanate coupling agents and aluminum coupling agents, and epoxy resins.

Silane coupling agents include γ-aminopropyltriethoxysilane, γ-aminopropyltrimethoxysilane, N-β (aminoethyl)-γ-aminopropyltrimethoxysilane, N-β (aminoethyl)-γ-amino Aminosilanes such as propyltrimethyldimethoxysilane and N-phenyl-γ-aminopropyltrimethoxysilane; β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxy epoxysilanes such as propyltriethoxysilane; vinylsilanes such as vinyltris(β-methoxyethoxy)silane, vinyltriethoxysilane, vinyltrimethoxysilane, γ-methacryloxypropyltrimethoxysilane; hexamethyldisilazane, γ-mercaptopropyltri methoxysilane and the like.

Titanate-based coupling agents include, for example, tetraisopropoxytitanium, tetra-n-butoxytitanium, butyl titanate dimer, tetrastearyl titanate, titanium acetylacetonate, titanium lactate, tetraoctylene glycol titanate, titanium lactate, tetrastearoxy Titanium etc. are mentioned.

Examples of aluminum-based coupling agents include acetoalkoxyaluminum diisopropylate.

As the epoxy resin, generally commercially available epibis type, novolac type, β-methyl epichloro type, cyclic oxirane type, glycidyl ether type, glycidyl ester type, polyglycol ether type, glycol ether type, epoxidized fatty acid ester type, poly Various epoxy resins such as carboxylic acid ester type, aminoglycidyl type, resorcinol type, triglycidyl tris(2-hydroxyethyl) isocyanurate, neopentyl glycol diglycidyl ether, 1,6-hexanediol diglycidyl ether, acryl glycidyl compounds such as ether, 2-ethylhexyl glycidyl ether, phenyl glycidyl ether, phenol glycidyl ether, pt-butylphenyl glycidyl ether, diglycidyl adipate, o-diglycidyl phthalate, glycidyl methacrylate, butyl glycidyl ether; mentioned.

(pigment)
Pigments are not particularly limited, and include extender pigments, white pigments, black pigments, gray pigments, red pigments, brown pigments, green pigments, blue pigments, and pigments described in the 1970 edition of Handbook of Paint Raw Materials (edited by the Japan Paint Manufacturers Association). Examples include organic pigments such as metal powder pigments, luminescent pigments, and pearlescent pigments, inorganic pigments, and plastic pigments.

Extender pigments include, for example, precipitated barium sulfate, rice flour, precipitated calcium carbonate, calcium bicarbonate, Kansui stone, alumina white, silica, hydrous fine silica (white carbon), ultrafine anhydrous silica (Aerosil), silica sand (silica sand), talc, precipitated magnesium carbonate, bentonite, clay, kaolin, loess, and the like.

Specific examples of organic pigments include various insoluble azo pigments such as Benzidine Yellow, Hansa Yellow and Laked 4R; soluble azo pigments such as Laked C, Carmine 6B and Bordeaux 10; various (copper) pigments such as phthalocyanine blue and phthalocyanine green. Phthalocyanine pigments; various chlorine dyeing lakes such as rhodamine lake and methyl violet lake; various mordant pigments such as quinoline lake and fast sky blue; various pigments such as anthraquinone pigments, thioindigo pigments and perinone pigments vat dye-based pigments; various quinacridone-based pigments such as Cincasia Red B; various dioxazine-based pigments such as dioxazine violet; various condensed azo pigments such as chromophtal;

Examples of inorganic pigments include various chromates such as yellow lead, zinc chromate, molybdate orange; various ferrocyanic compounds such as Prussian blue; Various metal oxides such as zirconium oxide; various sulfides and selenides such as cadmium yellow, cadmium red, and mercury sulfide; various sulfates such as barium sulfate and lead sulfate; various types of silicon such as calcium silicate and ultramarine blue. acid salts; various carbonates such as calcium carbonate and magnesium carbonate; various phosphates such as cobalt violet and manganese purple; various metal powder pigments such as aluminum powder, gold powder, silver powder, copper powder, bronze powder and brass powder; These metal flake pigments and mica flake pigments; metallic pigments and pearl pigments such as mica-like iron oxide pigments and mica-like iron oxide pigments coated with metal oxides; graphite, carbon black and the like.

Examples of plastic pigments include "Glandol PP-1000" and "PP-2000S" manufactured by DIC Corporation.

The pigment to be used may be appropriately selected according to the purpose. For example, inorganic oxides such as titanium oxide and zinc oxide are preferably used as white pigments because they are excellent in durability, weather resistance, and design. Carbon black is preferably used as the pigment.

The amount of the pigment compounded is, for example, 1 to 400 parts by mass with respect to 100 parts by mass of the total solid content of the polyisocyanate composition (A) and the polyol composition (B). 10 to 300 parts by mass is more preferable.

(Plasticizer)
Examples of plasticizers include phthalic acid-based plasticizers, fatty acid-based plasticizers, aromatic polycarboxylic acid-based plasticizers, phosphoric acid-based plasticizers, polyol-based plasticizers, epoxy-based plasticizers, polyester-based plasticizers, and carbonate-based plasticizers. plasticizers, and the like.

Examples of phthalic plasticizers include dimethyl phthalate, diethyl phthalate, dibutyl phthalate, diisobutyl phthalate, dihexyl phthalate, diheptyl phthalate, di-(2-ethylhexyl) phthalate, di-n-octyl phthalate, dinonyl phthalate, diisononyl phthalate, didecyl phthalate, diisodecyl phthalate, ditridecyl phthalate, diundecyl phthalate, dilauryl phthalate, distearyl phthalate, diphenyl phthalate, dibenzyl phthalate, butylbenzyl phthalate, dicyclohexyl phthalate, octyldecyl phthalate, dimethyl isophthalate, Phthalic ester plasticizers such as di-(2-ethylhexyl) isophthalate and diisooctyl isophthalate, tetrahydro phthalates such as di-(2-ethylhexyl) tetrahydrophthalate, di-n-octyltetrahydrophthalate and diisodecyltetrahydrophthalate Examples include phthalate plasticizers.

Examples of fatty acid-based plasticizers include adipic acids such as di-n-butyl adipate, di-(2-ethylhexyl) adipate, diisodecyl adipate, diisononyl adipate, di(C6-C10 alkyl) adipate, and dibutyl diglycol adipate. azelaic acid plasticizers such as di-n-hexyl azelate, di-(2-ethylhexyl) azelate, diisooctyl azelate, di-n-butyl sebacate, di-(2- ethylhexyl) sebacate, diisononyl sebacate and other sebacic acid plasticizers, e.g. , di-n-butyl fumarate, di-(2-ethylhexyl) fumarate and other fumaric acid plasticizers such as monomethyl itaconate, monobutyl itaconate, dimethyl itaconate, diethyl itaconate, dibutyl itaconate, Itaconic acid plasticizers such as di-(2-ethylhexyl) itaconate, stearic acid plasticizers such as n-butyl stearate, glycerin monostearate, diethylene glycol distearate, butyl oleate, glyceryl monooleate, Oleic acid plasticizers such as diethylene glycol monooleate, citric acid such as triethyl citrate, tri-n-butyl citrate, acetyltriethyl citrate, acetyltributyl citrate, acetyl tri-(2-ethylhexyl) citrate ricinoleic acid plasticizers such as methyl acetyl ricinoleate, butyl acetyl ricinoleate, glyceryl monoricinoleate, diethylene glycol monoricinoleate, and diethylene glycol monolaurate, diethylene glycol dipelargonate, pentaerythritol fatty acid esters, etc. and other fatty acid-based plasticizers.

Examples of aromatic polycarboxylic acid-based plasticizers include tri-n-hexyl trimellitate, tri-(2-ethylhexyl) trimellitate, tri-n-octyl trimellitate, triisooctyl trimellitate, and triisononyl. trimellitate, tridecyl trimellitate, triisodecyl trimellitate and other trimellitic acid plasticizers, e.g., tetra-(2-ethylhexyl) pyromellitate, tetra-n-octyl pyromellitate and other pyromellitic acid plasticizers plasticizers, and the like.

Phosphate plasticizers include, for example, triethyl phosphate, tributyl phosphate, tri-(2-ethylhexyl) phosphate, tributoxyethyl phosphate, triphenyl phosphate, octyldiphenyl phosphate, cresyldiphenyl phosphate, cresylphenyl phosphate, trichlé Zyl phosphate, trixylenyl phosphate, tris(chloroethyl) phosphate, tris(chloropropyl) phosphate, tris(dichloropropyl) phosphate, tris(isopropylphenyl) phosphate and the like.

Examples of polyol plasticizers include diethylene glycol dibenzoate, dipropylene glycol dibenzoate, triethylene glycol dibenzoate, triethylene glycol di-(2-ethylbutyrate), triethylene glycol di-(2-ethylhexoate ), glycol-based plasticizers such as dibutylmethylene bisthioglycolate, and glycerin-based plasticizers such as glycerol monoacetate, glycerol triacetate, and glycerol tributyrate.

Examples of epoxy plasticizers include epoxidized soybean oil, epoxybutyl stearate, di-2-ethylhexyl epoxyhexahydrophthalate, diisodecyl epoxyhexahydrophthalate, epoxy triglyceride, epoxidized octyl oleate, and epoxidized decyl oleate. etc.

Examples of polyester plasticizers include adipic acid-based polyesters, sebacic acid-based polyesters, and phthalic acid-based polyesters.

Carbonate-based plasticizers include propylene carbonate and ethylene carbonate.

Other plasticizers include partially hydrogenated terphenyl, adhesive plasticizers, diallyl phthalate, and polymerizable plasticizers such as acrylic monomers and oligomers. These plasticizers can be used alone or in combination of two or more.

(Form of adhesive)
The adhesive of the present invention is used in solventless form. In this specification, the term "solvent-free" adhesive means that the polyisocyanate composition (A) and the polyol composition (B) are esters such as ethyl acetate, butyl acetate and cellosolve acetate, acetone, methyl ethyl ketone and isobutyl ketone. , ketones such as cyclohexanone, ethers such as tetrahydrofuran and dioxane, aromatic hydrocarbons such as toluene and xylene, halogenated hydrocarbons such as methylene chloride and ethylene chloride, soluble hydrocarbons such as dimethylsulfoxide and dimethylsulfamide. A method that substantially does not contain expensive organic solvents, especially ethyl acetate or methyl ethyl ketone, and after applying an adhesive to a base material, attaches it to another base material without going through the process of heating in an oven or the like to volatilize the solvent. , refers to the form of the adhesive used in the so-called non-solvent lamination method. The constituent components of the polyisocyanate composition (A) or the polyol composition (B) and the organic solvent used as the reaction medium during the production of the raw materials cannot be completely removed, resulting in the polyisocyanate composition (A) or the polyol composition ( If a small amount of organic solvent remains in B), it is understood that the organic solvent is not substantially contained. Moreover, when the polyol composition (B) contains a low-molecular-weight alcohol, the low-molecular-weight alcohol reacts with the polyol composition (B) and becomes part of the coating film, so it is not necessary to volatilize after coating. Such forms are therefore also treated as solventless adhesives and low molecular weight alcohols are not considered organic solvents.

Unlike solvent-based adhesives, solvent-free adhesives must have a viscosity that allows coating without being diluted with an organic solvent. If the viscosity is low at a lower temperature, it is preferable because it is excellent in low-temperature processability. · less than s (viscosity in this specification refers to a value measured using a rotational viscometer, cone plate: 1° x diameter 50 mm, shear rate: 100 sec ^-1 , 70°C ± 1°C). The adhesive of the present invention has excellent initial cohesive strength while being within a practical viscosity range.

As will be described later, the solvent-free adhesive is heated to about 40° C. to 100° C. when it is applied to the film, and then the temperature drops while it is laminated with another film and wound up. At this time, a part of the polyester polyol (B1) is crystallized to increase the cohesive force of the adhesive coating film, so that the adhesive has a viscosity suitable for non-solvent lamination and excellent initial cohesive force.

Also, when only the polyester polyol (B1) is used as the polyol composition (B), the heat-sealing property is lowered, but this can be improved by using the polyester polyol (B2) together with the polyester polyol (B1) in a specific proportion. solved. When the polyester polyol (B1) is used alone, the compatibility with the polyisocyanate compound (A1), which is amorphous, is poor, the adhesion to the film is lowered, and the heat seal strength is weakened. By using the amorphous polyester polyol (B2) together here, the compatibility of the polyisocyanate compound (A1), the polyester polyol (B1), and the polyester polyol (B2) and the adhesion to the film are improved, and the adhesion is improved. This is probably because the crosslink density of the cured coating film of the agent increases.

<Laminate>
The laminate of the present invention is obtained by laminating a first substrate and a second substrate with the two-liquid curing adhesive of the present invention and curing the adhesive. The substrate used is preferably a plastic film that is commonly used in laminates. For example, as the first base material, polyethylene terephthalate (hereinafter abbreviated as PET) film, nylon (hereinafter abbreviated as Ny) film, biaxially oriented polypropylene (hereinafter abbreviated as OPP) film, metal such as aluminum or the like is added to these films. , vapor-deposited films provided with vapor-deposited layers of inorganic oxides such as silica and alumina, and aluminum foils. In addition, as the second base material, sealant films such as unstretched polypropylene (hereinafter abbreviated as CPP) film, linear low density polyethylene (hereinafter abbreviated as LLDPE) film, and a sealant film provided with a metal deposition layer such as aluminum A vapor-deposited sealant film and the like are included. Paper can also be used as the substrate. Examples of paper include natural paper and synthetic paper. A printed layer may be provided on the outer surface or the inner surface side of the substrate layer and the paper layer, if necessary. The printing layer can be provided by printing solvent type, water-based type, active energy ray-curable printing ink, or the like by a known method such as gravure printing, flexographic printing, offset printing, or inkjet printing.

Laminates obtained in this manner are industrially used as packaging materials for filling detergents and medicines, such as flexible packaging films and flexible packaging materials (packages whose shape is formed by putting contents in them). be able to. Specific uses include detergents and chemicals such as liquid laundry detergents, liquid kitchen detergents, liquid bath detergents, liquid bath soaps, liquid shampoos, and liquid conditioners.

The laminate of the present invention is prepared by applying the adhesive of the present invention heated to about 40° C. to 100° C. to a film material serving as a base material using a roll such as a gravure roll, and then immediately applying the other base material. By laminating, the laminate of the present invention is obtained. It is preferable to perform an aging treatment after lamination. The aging temperature is preferably room temperature to 70° C., and the aging time is preferably 6 to 240 hours.
The coating amount of the adhesive is appropriately adjusted, and is, for example, 1 g/m ² or more and 5 g/m ² or less, preferably 1 g/m 2 ^or more and 3 g/m ² or less.

<Packaging material>
The packaging material of the present invention is formed by molding the laminate into a bag shape. Specifically, the laminated body is heat-sealed to form a packaging material. In addition, when considering the use as a packaging material, the required performance (easily tearable and hand-cutting), the rigidity and durability required as a packaging material (for example, impact resistance, pinhole resistance, etc.), Other layers may be laminated as desired. It is usually used with a substrate layer, a paper layer, a sealant layer, a non-woven fabric layer, and the like. A well-known method can be used as a method of laminating other layers. For example, an adhesive layer may be provided between other layers and laminated by a dry lamination method, a heat lamination method, a heat sealing method, an extrusion lamination method, or the like.

As a specific laminate structure, the first plastic film layer/adhesive layer/second plastic film layer, which can be suitably used for general packaging materials, lid materials, refill containers, etc., A second plastic film that can be suitably used for a substrate layer/adhesive layer/first plastic film layer/adhesive layer/second plastic film layer, a paper container, a paper cup, etc., in which the layer is a barrier layer. Layer/paper layer/adhesive layer/first plastic film layer/adhesive layer/second plastic film layer, second plastic film layer/paper layer/polyolefin resin layer/base layer/first plastic film layer/ Adhesive layer/second plastic film layer, paper layer/first plastic film layer/adhesive layer/sealant layer, second plastic film layer/adhesive layer/first plastic film layer that can be suitably used for a tube container, etc. plastic film layer/adhesive layer/second plastic film layer and the like. These laminates may have a printed layer, a topcoat layer, and the like, if necessary.

The first plastic film layer is, for example, polyester resin films such as polyethylene terephthalate (PET), polyethylene naphthalate (PEN), and polylactic acid (PLA); polyolefin resin films such as polypropylene; polystyrene resin films; Polyamide resin films such as p-xylylene adipamide (MXD6 nylon); polycarbonate resin films; polyacrylonitrile resin films; polyimide resin films; Ethylene-vinyl alcohol copolymer/nylon 6) and mixtures are used. Among them, those having mechanical strength and dimensional stability are preferable. In particular, among these, films arbitrarily stretched in biaxial directions are preferably used.

In addition, the first plastic film layer is a soft metal foil such as an aluminum foil in order to impart a barrier function, as well as a vapor deposition layer such as aluminum vapor deposition, silica vapor deposition, alumina vapor deposition, silica-alumina binary vapor deposition; vinylidene chloride resin , denatured polyvinyl alcohol, ethylene-vinyl alcohol copolymer, MXD nylon, or the like.

A conventionally known sealant resin can be used as the second plastic film layer. For example, polyethylene such as low density polyethylene (LDPE), linear low density polyethylene (LLDPE) and high density polyethylene (HDPE), acid-modified polyethylene, polypropylene (PP), acid-modified polypropylene, copolymerized polypropylene, ethylene-vinyl acetate Copolymers, ethylene-(meth)acrylic acid ester copolymers, ethylene-(meth)acrylic acid copolymers, polyolefin resins such as ionomers, and the like can be mentioned. Among them, polyethylene-based resins are preferable from the viewpoint of low-temperature sealability, and polyethylene is particularly preferable because it is inexpensive. The thickness of the sealant layer is not particularly limited, but is preferably in the range of 10 to 60 μm, more preferably in the range of 15 to 40 μm, in consideration of processability to packaging materials and heat sealability. In addition, by providing the sealant layer with unevenness having a height difference of 5 to 20 μm, it is possible to provide the sealant layer with slipperiness and tearability of the packaging material.

Examples of the paper layer include natural paper and synthetic paper. A printed layer may be provided on the outer surface or the inner surface side of the substrate layer and the paper layer, if necessary.

The "other layer" may contain known additives and stabilizers such as antistatic agents, easy adhesion coating agents, plasticizers, lubricants and antioxidants. In addition, the "other layer" is a pretreatment such as corona treatment, plasma treatment, ozone treatment, chemical treatment, solvent treatment, etc., on the surface of the film in order to improve adhesion when laminated with other materials. may

Embodiments of the packaging material of the present invention include a three-side seal bag, a four-side seal bag, a gusset packaging bag, a pillow packaging bag, a gobel-top type bottomed container, a tetra classic, a Bruck type, a tube container, a paper cup, a lid material, and the like. There are various. Moreover, the packaging material of the present invention may be appropriately provided with an easy-opening treatment or resealing means.

The packaging material of the present invention can be used industrially as a packaging material mainly filled with foods, detergents and medicines. Specific uses include detergents and chemicals such as liquid laundry detergents, liquid kitchen detergents, liquid bath detergents, liquid bath soaps, liquid shampoos, liquid conditioners, and pharmaceutical tablets.

Hereinafter, the present invention will be described in more detail with specific synthesis examples and examples, but the present invention is not limited to these examples. In the following examples, "parts" and "%" represent "mass parts" and "mass%", respectively, unless otherwise specified.

<Adjustment of polyisocyanate composition (A)>
A polyisocyanate composition (A) was obtained by mixing a nurate form of isophorone diisocyanate and a nurate form of hexamethylene diisocyanate at a ratio of 1:4.

<Preparation of polyol composition (B)>
(Synthesis Example 1) Synthesis of polyester polyol (B1-1) 47.5 parts of 1,6 hexanediol was added to a 2-liter four-necked glass flask equipped with a stirring blade, temperature sensor, nitrogen gas inlet tube and rectifying column. 52.5 parts by mass of adipic acid were charged. The temperature was gradually raised to 220°C while performing dehydration reaction under normal pressure nitrogen stream, and the reaction was continued at 220°C. After confirming that the top temperature of the rectifying column has become 80° C. or lower, the rectifying column is removed, the condenser is switched to a glass condenser, a line is connected from the nitrogen gas introduction pipe to a vacuum pump, and the pressure is reduced to a predetermined level under a reduced pressure of 50 Torr. A condensation reaction was carried out until oxidation was reached to obtain a polyester polyol (B1-1). Table 1 shows the average functional group number, acid value, hydroxyl value and melting point of the polyester polyol (B1-1).

(Synthesis Example 2), (Comparative Synthesis Example 1)
Polyester polyols (B1-2) and (BH1-1) were obtained in the same manner as in (Synthesis Example 1) except that the raw materials shown in Table 1 were used. Table 1 shows the average functional group number, acid value, hydroxyl value and melting point of the polyester polyols (B1-2) and (BH1-1).

(Synthesis Example 3) Synthesis of polyester polyol (B2-1) Into a 2-liter four-necked glass flask equipped with a stirring blade, a temperature sensor, a nitrogen gas inlet tube and a rectifying column, 3.2 parts by mass of ethylene glycol, 9.3 parts by mass of diethylene glycol, 13.6 parts by mass of neopentyl glycol, 9.3 parts by mass of 1,6-hexanediol, 9.1 parts by mass of trimethylolpropane, 25.2 parts by mass of adipic acid, and 26.0 parts by mass of isophthalic acid and 4.3 parts by mass of sebacic acid were charged. The temperature was gradually raised to 250° C. while performing a dehydration reaction under a normal pressure nitrogen stream, and the reaction was continued at 250° C. for 3 hours. After confirming that the top temperature of the rectifying column became 80°C or less, the temperature was cooled to 240°C. The rectifying column was removed and switched to a glass condenser, and a line was connected from the nitrogen gas introduction pipe to a vacuum pump, and condensation reaction was carried out under a reduced pressure of 50 Torr until a predetermined oxidation was reached to obtain a polyester polyol (B2-1). . Table 2 shows the tri- or more functional glycol fraction, average functional group number, acid value and hydroxyl value of the polyester polyol (B2-1).

(Synthesis Example 4)-(Synthesis Example 6), (Comparative Synthesis Example 2)
Polyester polyols (B2-2) to (B2-4) and (BH2-1) were obtained in the same manner as in (Synthesis Example 3) except that the raw materials shown in Table 2 were used. Table 2 shows the trifunctional or higher glycol fraction, average functional group number, acid value and hydroxyl value of polyester polyols (B2-2) to (B2-4) and (BH2-1).

<Preparation of adhesive>
An adhesive of Example 1 was prepared by mixing polyester polyol (B1-1): 1.1 parts, polyester polyol (B2-1): 2.5 parts, and polyisocyanate composition (A): 2 parts. Adhesives of Examples and Comparative Examples were prepared in the same manner except that the polyester polyols (B1) and (B2) used and their blending amounts were changed as shown in Table 3-6.
In the table, (B1)/(B2) indicates the blending amount of polyester polyol (B1) and the blending amount of polyester polyol (B2) in the total amount of polyester polyol (B1) and polyester polyol (B2) ( % by mass). Comparative Examples 1-7 are left blank because they do not contain at least one or both of the polyester polyols (B1) and (B2).

<Production of evaluation sample>
(Evaluation sample 1)
An adhesive was applied to a PET film having a thickness of 50 μm so that the coating amount was 2.0 g/m ² , and then the adhesive-coated surface and the PET film having a thickness of 50 μm were laminated. Immediately after the bonding, a piece having an adhesive surface of 10 mm×10 mm was cut out and used as an evaluation sample 1 .

(Evaluation sample 2)
An adhesive is applied to a nylon film with a thickness of 15 μm so that the coating amount is 2.0 g / m ² , and then the adhesive coated surface and a linear low density polyethylene film (LLDPE) with a thickness of 60 μm are separated. pasted together. Aging was performed at 40° C./3 days, and a sample 2 for evaluation was obtained.

<Evaluation>
(70°C blending viscosity)
The viscosities at 70° C. of the adhesives of Examples and Comparative Examples immediately after being adjusted according to the formulations in Tables 3-6 were measured with a rotational viscometer and evaluated according to the following four levels. A practical level is less than 1100 mPa·s.
◎: Less than 700 mPa s ○: 700 mPa s or more and less than 1100 mPa s △: 1100 mPa s or more and less than 1500 mPa s
×: 1500 mPa s or more

(initial cohesive strength)
Using an Instron type tensile tester, the shear strength of the evaluation sample 1 was measured under the conditions of an atmospheric temperature of 25° C. and a peel rate of 5 mm/min, and the results are summarized in Table 3-6. The practical level is 1N/100m ² or more.

(Heat seal strength)
The sealant film surfaces of the evaluation sample 2 were heat-sealed using a 10 mm wide seal bar under the conditions of 180° C., 10 N/cm ² and 1 second. The tensile strength (N/15 mm) between the sealant films was measured under the conditions of an ambient temperature of 25° C., a peeling speed of 300 mm/min, and a T-type, and evaluated in the following four stages, and summarized in Table 3-6.
◎: 55 N / 15 mm or more ○: 50 N / 15 mm or more and less than 55 N / 15 mm △: 40 N / 15 mm or more and less than 50 N / 15 mm ×: less than 40 N / 15 mm

As is clear from the examples, the adhesive of the present invention had a good balance of initial cohesive strength and heat seal strength. On the other hand, Comparative Example 1 containing no polyester polyol (B1), Comparative Examples 2 and 8 with a small amount, and Comparative Examples 6 and 7 using a crystalline polyester polyol with a too low melting point exhibit sufficient initial cohesive strength. didn't. Further, in Comparative Examples 3, 4, and 5 in which a polyester polyol having an average number of functional groups of 2 was used in combination, and in Comparative Example 9 in which the amount of the polyester polyol (B2) was small, sufficient heat seal strength was not exhibited.

Claims (6)

A polyisocyanate composition (A) and a polyol composition (B),
The polyol composition (B) comprises a crystalline polyester polyol (B1) having a melting point of 50° C. or higher and 70° C. or lower and an amorphous polyester polyol having an average functional group number of 2.01 or higher and 2.2 or lower ( B2) and
The blending amount of the polyester polyol (B1) in the total amount of the polyester polyol (B1) and the polyester polyol (B2) is 15% by mass or more and 85% by mass or less, and the blending amount of the polyester polyol (B2) in the total amount. A two-component adhesive with an amount of 15% by mass or more and 85% by mass or less. The blending amount of the polyester polyol (B1) in the total amount is 45% by mass or more and 85% by mass or less, and the blending amount of the polyester polyol (B2) is 15% by mass or more and 55% by mass or less. 2 liquid type adhesive. The polyester polyol (B2) is a reaction product of a monomer composition containing a polyhydric carboxylic acid and a polyhydric alcohol, and the monomer composition can react with at least one of the polyhydric carboxylic acid and the polyhydric alcohol. 2. The two-part adhesive according to claim 1, which contains a penta- or higher-functional compound. The ratio [NCO]/[OH] of the number of moles [NCO] of the isocyanate groups contained in the polyisocyanate composition (A) and the number of moles [OH] of the hydroxyl groups contained in the polyol composition (B) is 1. .0 to 3.0, the two-component adhesive according to claim 1. A first base material, a second base material, and an adhesive layer that bonds the first description and the second base material, and the adhesive layer is any one of claims 1 to 4. A laminate which is a cured coating film of the two-component adhesive according to 1. A packaging material comprising the laminate according to claim 5 .