JP7030139B2 - Two-component curable solvent-free adhesive and laminated film - Google Patents

Description

The present invention relates to a two-component curable solvent-free adhesive and a laminated film, and more particularly, a two-component curable solvent-free adhesive suitable as a laminate adhesive and a two-component curable solvent-free adhesive thereof. Regarding the laminated film obtained by using.

Laminated films, in which various films are attached with a laminated adhesive, are widely used in the field of packaging materials. In particular, a laminated film obtained by laminating a plastic film and a metal foil with a laminating adhesive has excellent light-shielding properties and barrier properties of gas and liquid, and is widely used as various packaging materials.

The laminating adhesive used for such a laminated film includes a diisocyanate group-terminated prepolymer which is a reaction product of xylylene diisocyanate and polyester diol, a polyisocyanate component containing an allophanate modified product of hexamethylene diisocyanate, and a polyester diol. A two-component curable solvent-free adhesive containing an acid-modified product of the above and a polyol component containing trimethylolpropane has been proposed, and further, 100 parts of the two-component curable solvent-free adhesive has no phosphoric acid. It has also been proposed to add .033 parts and 0.67 parts of γ-glycidoxypropyltrimethoxysilane (see, for example, Patent Document 1 (Example 1)).

Japanese Unexamined Patent Publication No. 2011-162656

On the other hand, in the two-component curable solvent-free adhesive described in Patent Document 1, it is necessary to remove unreacted xylylene diisocyanate in the polyisocyanate component by thin film distillation or the like from the viewpoint of work hygiene environment, which is troublesome. There is a problem that it takes.

On the other hand, since diphenylmethane diisocyanate has a relatively high vapor pressure, it is not necessary to remove unreacted diphenylmethane diisocyanate from the viewpoint of working hygiene environment.

However, depending on the residual ratio of unreacted diphenylmethane diisocyanate in the two-component curable solvent-free adhesive, an appropriate pot life cannot be obtained, and as a result, there is a problem that an appearance defect is caused.

Further, the two-component curable solvent-free adhesive is required to have low-temperature curability (room temperature curing property), and further, it is required to obtain a laminated film having excellent content resistance depending on the application.

INDUSTRIAL APPLICABILITY The present invention is a two-component curable type that can produce a laminated film having excellent production efficiency, an appropriate pot life, suppression of appearance defects, excellent low-temperature curability, and excellent content resistance. It is a laminated film obtained by using a solvent-based adhesive and its two-component curable solvent-free adhesive.

The present invention [1] is a two-component curable solvent-free adhesive containing a polyisocyanate component and a polyol component, wherein the polyisocyanate component is a reaction product of diphenylmethane diisocyanate and a polyol, and an isocyanate group-terminated prepolymer. , Unreacted diphenylmethane diisocyanate, the polyol component contains a polyester polyol having a number average molecular weight of 1000 or less, and the unreacted diphenylmethane with respect to 100 parts by mass of the two-component curable solvent-free adhesive. The diisocyanate is 20 parts by mass or more and 30 parts by mass or less, and contains 0.003 parts by mass or more and 0.030 parts by mass or less of phosphoric acid with respect to 100 parts by mass of the total amount of the two-component curable solvent-free adhesive. Contains a two-component curable solvent-free adhesive.

The present invention [2] contains 0.2 parts by mass or more and 5.0 parts by mass or less of a silane coupling agent with respect to 100 parts by mass of the total amount of the two-component curable solvent-free adhesive. ] Contains the two-component curable solvent-free adhesive described in.

The present invention [3] includes the two-component curable solvent-free adhesive according to the above [1] or [2], wherein the polyol component contains a trihydric or higher alcohol.

The present invention [4] includes a laminated film including an adhesive layer made of the two-component curable solvent-free adhesive according to any one of the above [1] to [3].

The two-component curable solvent-free adhesive of the present invention contains a polyisocyanate component and a polyol component, and further contains unreacted diphenylmethane diisocyanate and phosphoric acid in a predetermined ratio.

Therefore, the two-component curable solvent-free adhesive of the present invention has excellent production efficiency, has an appropriate pot life, can suppress appearance defects, has excellent low-temperature curability, and has content resistance. It is possible to manufacture an excellent laminated film.

Further, since the laminating film of the present invention contains the adhesive layer made of the above-mentioned two-component curable solvent-free adhesive, it is excellent in production efficiency, appearance and content resistance.

The two-component curable solvent-free adhesive of the present invention does not contain an organic solvent and water, but contains a polyisocyanate component and a polyol component. In the two-component curable solvent-free adhesive, the polyisocyanate component and the polyol component are individually prepared and mixed immediately before use.

The polyisocyanate component contains an isocyanate group-terminated prepolymer which is a reaction product of diphenylmethane diisocyanate and a polyol, and unreacted diphenylmethane diisocyanate.

Examples of the diphenylmethane diisocyanate include 4,4'-diphenylmethane diisocyanate, 2,4'-diphenylmethane diisocyanate, 2,2'-diphenylmethane diisocyanate and the like.

These diphenylmethane diisocyanates can be used alone or in combination of two or more.

The diphenylmethane diisocyanate preferably contains 4,4'-diphenylmethane diisocyanate and, if necessary, 2,4'-diphenylmethane diisocyanate and / or 2,2'-diphenylmethane diisocyanate. More preferably, the diphenylmethane diisocyanate contains 4,4'-diphenylmethane diisocyanate and 2,4'-diphenylmethane diisocyanate (liquid diphenylmethane diisocyanate). The ratio thereof is appropriately set according to the purpose and use.

Examples of the polyol include a low molecular weight polyol and a high molecular weight polyol.

Examples of the low molecular weight polyol include organic compounds having two or more hydroxyl groups in the molecule and having a molecular weight of 50 or more and 300 or less, preferably 400 or less.

Specific examples of the low molecular weight polyol include ethylene glycol, propylene glycol, 1,3-propanediol, 1,4-butylene glycol, 1,3-butylene glycol, 1,2-butylene glycol, and 1,5-. Pentandiol, 1,6-hexanediol, neopentylglycol, 3-methyl-1,5-pentanediol, 2,2,2-trimethylpentanediol, 3,3-dimethylolheptan, alcohol (C7-20) diol , 1,3- or 1,4-cyclohexanedimethanol and mixtures thereof, 1,3- or 1,4-cyclohexanediol and mixtures thereof, bisphenol hydride A, 1,4-dihydroxy-2-butene, 2 , 2-hydric alcohols such as 6-dimethyl-1-octene-3,8-diol, bisphenol A, diethylene glycol, triethylene glycol, dipropylene glycol, for example, trihydric alcohols such as glycerin, trimethylolpropane, triisopropanolamine, For example, tetrahydric alcohols such as tetramethylolmethane (pentaerythritol) and diglycerin, for example, pentahydric alcohols such as xylitol, for example, sorbitol, mannitol, aritol, iditol, darsitol, altritor, inositol, dipentaerythritol and the like 6 Hydrate alcohols, such as heptavalent alcohols such as persetol, such as octavalent alcohols such as sucrose, and the like can be mentioned.

These low molecular weight polyols can be used alone or in combination of two or more.

As the low molecular weight polyol, preferably, a trihydric alcohol is mentioned, and more preferably, trimethylolpropane is mentioned.

Examples of the high molecular weight polyol include high molecular weight compounds (preferably polymers) having two or more hydroxyl groups in the molecule and having a number average molecular weight of more than 300, preferably more than 400.

Specific examples of the high molecular weight polyols include polyether polyols, polyester polyols, polycarbonate polyols, polyurethane polyols, epoxy polyols, vegetable oil polyols, polyolefin polyols, acrylic polyols, vinyl monomer-modified polyols and the like.

Preferred examples of the high molecular weight polyol include a polyether polyol, a polyester polyol, and a polycarbonate polyol.

Examples of the polyether polyol include polyoxyalkylene polyol, polytrimethylene ether glycol, polytetramethylene ether polyol and the like.

Examples of the polyether polyol include a polyoxyalkylene polyol and a polytetramethylene ether polyol.

Examples of the polyoxyalkylene polyol include the above-mentioned low molecular weight polyol and an addition polymer of alkylene oxide using a known low molecular weight polyamine as an initiator.

Examples of the alkylene oxide include propylene oxide, ethylene oxide, butylene oxide and the like. In addition, these alkylene oxides can be used alone or in combination of two or more. Of these, propylene oxide and ethylene oxide are preferable. In addition, polyoxyalkylene polyols include, for example, polyethylene glycol, polypropylene glycol, random and / or block copolymers of propylene oxide and ethylene oxide.

Examples of the polytrimethylene ether glycol include glycols obtained by a polycondensation reaction of 1,3-propanediol derived from a plant component.

Examples of the polytetramethylene ether polyol include a ring-opening polymer obtained by cationic polymerization of tetrahydrofuran (polytetramethylene ether glycol (crystalline)), alkyl-substituted tetrahydrofuran in a polymerization unit such as tetrahydrofuran, and the above-mentioned divalent. Examples thereof include amorphous (non-crystalline) polytetramethylene ether glycol obtained by copolymerizing alcohol.

Examples of the polyester polyol include a polycondensate obtained by reacting a low molecular weight polyol with a polybasic acid under known conditions.

Examples of the low molecular weight polyol include the above-mentioned low molecular weight polyol, preferably a dihydric alcohol, and more preferably propylene glycol and neopentyl glycol.

Examples of the polybasic acid include oxalic acid, malonic acid, succinic acid, methylsuccinic acid, glutaric acid, adipic acid, 1,1-dimethyl-1,3-dicarboxypropane, and 3-methyl-3-ethylglutaric acid. , Azelaic acid, Sevacinic acid and other saturated aliphatic dicarboxylic acids (C11-13), such as maleic acid, fumaric acid, itaconic acid and other unsaturated aliphatic dicarboxylic acids, such as phthalic acid, isophthalic acid, terephthalic acid, toluene. Aromatic dicarboxylic acids such as dicarboxylic acids and naphthalenedicarboxylic acids, eg alicyclic dicarboxylic acids such as hexahydrophthalic acids, such as other carboxylic acids such as dimer acid, hydrogenated dimer acid, het acid, and their carboxylic acids. Acid anhydrides derived from acids such as oxalic acid anhydride, succinic acid anhydride, maleic acid anhydride, phthalic acid anhydride, 2-alkyl anhydride (C12-C18) succinic acid, tetrahydrophthalic acid anhydride, trimellitic acid anhydride, and further. Examples thereof include acid halides derived from these carboxylic acids and the like, such as oxalic acid dichloride, adipic acid dichloride, and sebacic acid dichloride.

These polybasic acids can be used alone or in combination of two or more.

Examples of the polybasic acid include saturated aliphatic dicarboxylic acid, aromatic dicarboxylic acid and acid anhydride, more preferably adipic acid, phthalic acid and phthalic anhydride, and further preferably adipic acid. Can be mentioned.

Further, as the polyester polyol, for example, a plant-derived polyester polyol, specifically, the above-mentioned low molecular weight polyol as an initiator, a hydroxyl group-containing vegetable oil fatty acid (for example, lysinoleic acid-containing castor oil fatty acid, 12-hydroxystearic acid). Examples thereof include vegetable oil-based polyester polyols obtained by subjecting a hydroxycarboxylic acid such as (hydrogenated sardine oil fatty acid, etc.) containing the above to a condensation reaction under known conditions.

Further, as the polyester polyol, for example, using the above-mentioned low molecular weight polyol (preferably dihydric alcohol) as an initiator, for example, lactones such as ε-caprolactone and γ-valerolactone, and for example, L-lactide, D- Examples thereof include polycaprolactone polyols and polyvalerolactone polyols obtained by ring-opening polymerization of lactides such as lactide, and lactone-based polyester polyols obtained by copolymerizing them with the above dihydric alcohol.

Examples of the polycarbonate polyol include a ring-opening polymer (crystalline) of ethylene carbonate using the above-mentioned low molecular weight polyol (preferably the above-mentioned dihydric alcohol) as an initiator, and for example, 1,4-butanediol, 1, Examples thereof include an amorphous polycarbonate polyol obtained by copolymerizing a dihydric alcohol such as 5-pentanediol, 3-methyl-1,5-pentanediol and 1,6-hexanediol with a ring-opening polymer.

These high molecular weight polyols can be used alone or in combination of two or more.

Preferred high molecular weight polyols include polyester polyols and polyether polyols.

The number average molecular weight of the high molecular weight polyol is, for example, more than 300, preferably more than 400, more preferably 500 or more, still more preferably 600 or more. Further, for example, it is 5000 or less, preferably 4000 or less, more preferably 2000 or less, and further preferably 1000 or less.

The number average molecular weight of the high molecular weight polyol can be measured by the GPC method (standard polystyrene conversion), and can be calculated in detail from the hydroxyl value and the average number of functional groups, as will be described later.

These polyols can be used alone or in combination of two or more.

As the polyol, a high molecular weight polyol is preferably mentioned, and more preferably, a combination of a polyether polyol and a polyester polyol can be mentioned.

When the polyether polyol and the polyester polyol are used in combination, the combination ratio thereof is, for example, 50 parts by mass or more, preferably 60 parts by mass or more of the polyether polyol with respect to 100 parts by mass of the total amount thereof. Yes, for example, 90 parts by mass or less, preferably 80 parts by mass or less. The polyester polyol is, for example, 10 parts by mass or more, preferably 20 parts by mass or more, and for example, 50 parts by mass or less, preferably 40 parts by mass or less.

By using these in combination, it is possible to achieve both the excellent coatability derived from the polyether polyol and the excellent adhesiveness derived from the polyester polyol.

Then, in order to obtain the isocyanate group-terminated prepolymer, the above-mentioned diphenylmethane diisocyanate and the polyol are reacted by a polymerization method (preferably bulk polymerization) such as bulk polymerization or solution polymerization.

In bulk polymerization, for example, the reaction temperature of diphenylmethane diisocyanate and the polyol under a nitrogen stream is, for example, 50 ° C. or higher, for example, 250 ° C. or lower, preferably 200 ° C. or lower, for example, 0.5 hour or longer, for example. , React for 15 hours or less.

In solution polymerization, diphenylmethane diisocyanate and a polyol are added to an organic solvent, and the reaction temperature is, for example, 50 ° C. or higher, for example, 120 ° C. or lower, preferably 100 ° C. or lower, for example, 0.5 hour or longer, for example. , React for 15 hours or less.

Examples of the organic solvent include ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone and cyclohexanone, for example, nitriles such as acetonitrile, and alkyl esters such as methyl acetate, ethyl acetate, butyl acetate and isobutyl acetate, for example, n-. Aliphatic hydrocarbons such as hexane, n-heptane, octane, eg, alicyclic hydrocarbons such as cyclohexane, methylcyclohexane, eg aromatic hydrocarbons such as toluene, xylene, ethylbenzene, eg, methylserosolve acetate. Glycol ether esters such as, ethyl cellosolve acetate, methyl carbitol acetate, ethyl carbitol acetate, ethylene glycol ethyl ether acetate, propylene glycol methyl ether acetate, 3-methyl-3-methoxybutyl acetate, ethyl-3-ethoxypropionate. Such as ethers such as diethyl ether, tetrahydrofuran, dioxane, for example, halogenated aliphatic hydrocarbons such as methyl chloride, methylene chloride, chloroform, carbon tetrachloride, methyl bromide, methylene iodide, dichloroethane, for example. Examples thereof include polar aprotons such as N-methylpyrrolidone, dimethylformamide, N, N'-dimethylacetamide, dimethylsulfoxide, and hexamethylphosphonylamide.

When solution polymerization is adopted, the organic solvent is removed after the completion of the polymerization reaction, as will be described later.

Further, in the above-mentioned polymerization reaction, a known urethanization catalyst such as an amine or an organometallic compound can be added, if necessary.

Examples of the amines include tertiary amines such as triethylamine, triethylenediamine, bis- (2-dimethylaminoethyl) ether and N-methylmorpholine, and quaternary ammonium salts such as tetraethylhydroxylammonium, for example, imidazole. Examples thereof include imidazoles such as 2-ethyl-4-methylimidazole.

Examples of the organic metal compound include tin acetate, tin octylate (tin octylate), tin oleate, tin laurate, dibutyltin diacetate, dimethyltin dilaurate, dibutyltin dilaurate, dibutyltin dimercaptide, dibutyltin maleate, and dibutyl. Organic tin compounds such as tin dilaurate, dibutyl tin dineodecanoate, dioctyl tin dimercaptide, dioctyl tin dilaurylate, dibutyl tin dichloride, eg organic lead compounds such as lead octanoate, lead naphthenate, eg nickel naphthenate, etc. Examples thereof include organic nickel compounds, for example, organic cobalt compounds such as cobalt naphthenate, for example, organic copper compounds such as copper octate, for example, bismuth octanate (bismuth octylate), bismuth neodecanoate and the like, and the like. Preferred examples include tin octylate and bismuth octylate.

Further, examples of the urethanization catalyst include potassium salts such as potassium carbonate, potassium acetate and potassium octylate.

These urethanization catalysts can be used alone or in combination of two or more.

The addition ratio of the urethanization catalyst is, for example, 0.001 part by mass or more, preferably 0.01 part by mass or more, and for example, 1 part by mass or less, based on 10,000 parts by mass of the total amount of diphenylmethane diisocyanate and the polyol. It is preferably 0.5 parts by mass or less.

When an organic solvent is used in the above-mentioned polymerization reaction, the organic solvent is removed by a known removing means such as distillation or extraction to make it solvent-free.

The mixing ratio of the diphenylmethane diisocyanate and the polyol is preferably adjusted so that the remaining unreacted diphenylmethane diisocyanate has a ratio described later. More specifically, the equivalent ratio (isocyanate group / hydroxyl group) of the isocyanate group in the diphenylmethane diisocyanate to the hydroxyl group in the polyol is, for example, more than 4.0, preferably 4.1 or more, more preferably. It is 4.5 or more, more preferably 5.0 or more, and for example, less than 8.0, preferably 7.5 or less, more preferably 7.0 or less, still more preferably 6.5 or less. ..

On a mass basis, the amount of diphenylmethane diisocyanate is, for example, 52 parts by mass or more, preferably 55 parts by mass or more, preferably 65 parts by mass or less, preferably 65 parts by mass or more, based on 100 parts by mass of the total amount of the diphenylmethane diisocyanate and the polyol. , 60 parts by mass or less. The polyol is, for example, 35 parts by mass or more, preferably 40 parts by mass or more, and for example, 48 parts by mass or less, preferably 45 parts by mass or less.

This makes it possible to obtain an isocyanate group-terminated prepolymer.

The isocyanate group content (isocyanate group content) can be determined by a known method such as a titration method using di-n-butylamine or FT-IR analysis.

Further, the polyisocyanate component contains unreacted diphenylmethane diisocyanate.

The unreacted diphenylmethane diisocyanate is contained in the reaction product, for example, as an unreacted component in the production of the above-mentioned isocyanate group-terminated prepolymer.

Further, for example, the content of diphenylmethane diisocyanate can be adjusted by removing a part of unreacted diphenylmethane diisocyanate from the obtained reaction product by a distillation method, an extraction method or the like.

Further, for example, the content of diphenylmethane diisocyanate can be adjusted by separately adding diphenylmethane diisocyanate to the obtained reaction product.

Preferably, the equivalent ratio in the production of the above-mentioned isocyanate group-terminated prepolymer is adjusted so that the ratio of the unreacted diphenylmethane diisocyanate and the isocyanate group-terminated prepolymer is in the range described later, and the obtained reaction product is used as it is. Used as a polyisocyanate component.

The content ratio of unreacted diphenylmethane diisocyanate is, for example, 25 parts by mass or more, preferably 30 parts by mass or more, more preferably 32 parts by mass or more, and for example, with respect to 100 parts by mass of the total amount of the polyisocyanate component. It is 50 parts by mass or less, preferably 45 parts by mass or less, more preferably 40 parts by mass or less, and further preferably 35 parts by mass or less.

Further, the content ratio of the isocyanate group-terminated prepolymer is the above-mentioned balance, and is, for example, 50 parts by mass or more, preferably 55 parts by mass or more, and more preferably 60 parts by mass with respect to 100 parts by mass of the total amount of the polyisocyanate component. It is 5 parts by mass or more, more preferably 65 parts by mass or more, and for example, 75 parts by mass or less, preferably 70 parts by mass or less, and more preferably 68 parts by mass or less.

The content of unreacted diphenylmethane diisocyanate in the polyisocyanate component (including the reaction product in the production of the isocyanate group-terminated prepolymer) can be determined, for example, by HPLC measurement, and the above-mentioned isocyanate group-terminated. It can also be calculated as a theoretical concentration from the charging ratio of diphenylmethane diisocyanate and polyol in the production of prepolymer.

Further, the content of unreacted diphenylmethane diisocyanate is adjusted so as to be within a predetermined range with respect to the two-component curable solvent-free adhesive (that is, the total of the polyisocyanate component and the polyol component) described later.

More specifically, the content ratio of unreacted diphenylmethane diisocyanate is 100 parts by mass of a two-component curable solvent-free adhesive, which will be described later, from the viewpoint of suppressing appearance defects during low-temperature curing and improving the content resistance. 20 parts by mass or more, preferably 21 parts by mass or more, more preferably 22 parts by mass or more, 30 parts by mass or less, preferably 28 parts by mass or less, more preferably 25 parts by mass or less. be.

When the content ratio of unreacted diphenylmethane diisocyanate is within the above range, excellent coating appearance and low temperature curability can be obtained.

The content ratio of unreacted diphenylmethane diisocyanate in the two-component curable solvent-free adhesive can be determined, for example, by HPLC measurement, and is calculated as a theoretical concentration from the compounding ratio of the polyisocyanate component and the polyol component. You can also do it.

The isocyanate group equivalent of the polyisocyanate component is, for example, more than 210, preferably 230 or more, and for example, 320 or less, preferably 300 or less, preferably 250 or less.

The isocyanate group equivalent is synonymous with the amine equivalent, and can be determined by the method A or method B of JIS K 1603-1 (2007).

The polyol component contains a polyester polyol as an essential component.

Examples of the polyester polyol include the above-mentioned polyester polyol, and specific examples thereof include a polycondensate of a low molecular weight polyol and a polybasic acid, a plant-derived polyester polyol, and a lactone-based polyester polyol.

The polyester polyol preferably includes a polycondensate of a low molecular weight polyol and a polybasic acid.

Examples of the low molecular weight polyol include the above-mentioned low molecular weight polyol, preferably a dihydric alcohol, and more preferably diethylene glycol.

Examples of the polybasic acid include the above-mentioned polybasic acid, preferably a saturated aliphatic dicarboxylic acid and an aromatic dicarboxylic acid, and more preferably an adipic acid and a phthalic acid.

The method for polycondensing the low molecular weight polyol and the polybasic acid is not particularly limited, and a known method is adopted.

The number average molecular weight of the polyester polyol is 1000 or less, preferably 950 or less, more preferably 900 or less, still more preferably 850 or less, from the viewpoint of adjusting the viscosity in a solvent-free state. Further, for example, it is more than 300, preferably more than 400, more preferably 500 or more, still more preferably 600 or more.

The number average molecular weight of the polyester polyol can be measured by the GPC method, and can be calculated from the hydroxyl value and the average number of functional groups (the same applies hereinafter).

Preferably, the number average molecular weight of the polyester polyol is calculated from the hydroxyl value and the average number of functional groups by the following formula.

Number average molecular weight = hydroxyl value x average number of functional groups The hydroxyl value can be obtained from the acetylation method or the phthalation method based on the A method or the B method of JIS K 1557-1 (2007). Further, the average number of functional groups can be obtained from the charging ratio of each component constituting the polyester polyol and the number of functional groups.

Further, the polyol component may contain other high molecular weight polyols (high molecular weight polyols other than polyester polyols) and low molecular weight polyols as optional components.

Examples of other high molecular weight polyols include the above-mentioned polyether polyol and the above-mentioned polycarbonate polyol. Other high molecular weight polyols can be used alone or in combination of two or more.

Preferably, no other high molecular weight polyol is contained in the polyol component. In other words, the polyol component preferably contains the above-mentioned polyester polyol alone as a high molecular weight polyol.

Examples of the low molecular weight polyol include the above-mentioned low molecular weight polyol. The low molecular weight polyol can be used alone or in combination of two or more.

Preferred low molecular weight polyols include trihydric or higher alcohols. The trihydric or higher alcohol is a crosslinkable polyol, in other words, the polyol component preferably contains a crosslinkable polyol.

If the polyol component contains an alcohol having a valence of 3 or more, a two-component curable solvent-free adhesive having excellent low-temperature curability and content resistance can be obtained.

More specifically, the trihydric alcohol, for example, a trihydric alcohol such as glycerin, trimethylolpropane, triisopropanolamine, and a tetrahydric alcohol such as tetramethylolmethane (pentaerythritol) and diglycerin, for example, A pentahydric alcohol such as xylitol, for example, a hexahydric alcohol such as sorbitol, mannitol, aritol, iditol, darsitol, altritor, inositol, dipentaerythritol, for example, a heptavalent alcohol such as persetol, for example, an octavalent alcohol such as sucrose. Alcohol and the like can be mentioned.

These trihydric or higher alcohols can be used alone or in combination of two or more.

Examples of the trihydric or higher alcohol preferably include trihydric alcohol, more preferably glycerin and trimethylolpropane, and further preferably trimethylolpropane from the viewpoint of boil resistance.

The content ratio of the trivalent or higher alcohol is, for example, 0.1 part by mass or more, preferably 0.5 part by mass or more, and preferably 10 parts by mass or less, preferably 10 parts by mass or more, based on 100 parts by mass of the total amount of the polyol component. Is 5 parts by mass or less, more preferably 3 or less.

Further, the two-component curable solvent-free adhesive contains phosphoric acid.

More specifically, in a two-component curable solvent-free adhesive, either one or both of the polyisocyanate component and the polyol component contains phosphoric acid. Preferably, the polyol component contains phosphoric acid.

Examples of phosphoric acid include hypophosphoric acid, phosphoric acid, orthophosphoric acid, and hypophosphoric acid. In addition, examples of phosphoric acid include condensed phosphoric acid such as metaphosphoric acid, pyrophosphoric acid, tripolyphosphoric acid, polyphosphoric acid, and ultraphosphoric acid.

Further, as phosphoric acid, for example, a phosphate such as sodium or potassium or a condensed phosphate, for example, monomethyl orthophosphoric acid, monoethyl orthophosphoric acid, monopropyl orthophosphoric acid, monobutyl orthophosphate, mono-2-ethylhexyl orthophosphoric acid, Monoesters such as monophenyl orthophosphoric acid, monomethyl phosphite, monoethyl phosphite, monopropyl phosphite, monobutyl phosphite, mono-2-ethylhexyl phosphite, monophenyl phosphite, for example, orthophosphoric acid. Di-2-ethylhexyl, diphenyl orthophosphorate, trimethyl ortriate, triethyl orthophosphate, tripropyl orthophosphate, tributyl orthophosphate, tri-2-ethylhexyl orthophosphate, triphenyl orthophosphate, dimethyl phosphite, diethyl phosphite, Dipropyl phosphate, dibutyl phosphite, di-2-ethylhexyl phosphite, diphenyl phosphite, trimethyl phosphite, triethyl phosphite, tripropyl phosphite, tributyl phosphite, tri-triphosphate phosphite Examples thereof include di and triesters such as 2-ethylhexyl and triphenyl phosphite, and mono, di and triesters obtained from condensed phosphoric acid and alcohols.

These phosphoric acids can be used alone or in combination of two or more.

Phosphoric acid is preferably orthophosphoric acid.

The content ratio of phosphoric acid is 0.003 with respect to 100 parts by mass of the total amount of the two-component curable solvent-free adhesive from the viewpoint of suppressing poor appearance at low temperature curing and improving the content resistance. It is 0 parts by mass or more, preferably 0.005 parts by mass or more, more preferably 0.010 parts by mass or more, further preferably 0.012 parts by mass or more, and particularly preferably 0.014 parts by mass or more. .030 parts by mass or less, preferably 0.025 parts by mass or less, more preferably 0.020 parts by mass or less.

When phosphoric acid is contained in the polyol component, the amount of phosphoric acid is, for example, 0.005 part by mass or more, preferably 0.010 part by mass or more, based on 100 parts by mass of the total amount of the polyol component. It is preferably 0.030 parts by mass or more, more preferably 0.040 parts by mass or more, and for example, 0.090 parts by mass or less, preferably 0.070 parts by mass or less.

If the two-component curable solvent-free adhesive contains phosphoric acid in the above ratio, poor appearance can be suppressed, and low-temperature curability and content resistance can be improved.

Further, the two-component curable solvent-free adhesive preferably contains a silane coupling agent.

More specifically, in a two-component curable solvent-free adhesive, either one or both of the polyisocyanate component and the polyol component contains a silane coupling agent. Preferably, the polyol component contains a silane coupling agent.

The silane coupling agent is, for example, structural formula R-Si≡ (X) ₃ or R-Si≡ (R') (X) ₂ (in the formula, R is a vinyl group, an epoxy group, an amino group, an imino group, etc. It represents an organic group having an isocyanate group or a mercapto group, R'represents a lower alkyl group having 1 to 4 carbon atoms, and X represents a methoxy group, an ethoxy group or a chlor atom).

Specific examples of the silane coupling agent include chlorosilanes such as vinyltricrolsilane, for example, γ-glycidoxypropyltrimethoxysilane (also known as 3- (trimethoxysilyl) propylglycidyl ether) and γ-glycid. Epoxysilanes such as xypropyltriethoxysilane, β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, di (γ-glycidoxypropyl) dimethoxysilane, eg N-β- (aminoethyl) -γ- Aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, N-β- (aminoethyl) -γ-propylmethyldimethoxysilane, n- (dimethoxymethylsilylpropyl) ethylenediamine, n- (triethoxysilylpropyl) ethylenediamine, Aminosilanes such as N-phenyl-γ-aminopropyltrimethoxysilane, such as vinylsilanes such as vinyltriethoxysilane, such as isocyanatosilanes such as γ-isocyanatopropyltrimethoxysilane and γ-isocyanatopropyltriethoxysilane. Can be mentioned.

The silane coupling agent can be used alone or in combination of two or more.

The silane coupling agent preferably includes epoxysilane and aminosilane, more preferably epoxysilane, and particularly preferably γ-glycidoxypropyltrimethoxysilane (also known as 3- (trimethoxysilyl)). Propylglycidyl ether).

The content ratio of the silane coupling agent is, for example, 0.1 part by mass or more, preferably 0.15 part by mass or more, more preferably 0.1 part by mass, based on 100 parts by mass of the total amount of the two-component curable solvent-free adhesive. 0.2 parts by mass or more, for example, 15 parts by mass or less, preferably 10 parts by mass or less, more preferably 5.0 parts by mass or less, still more preferably 1.0 part by mass or less, still more preferably. It is 0.5 parts by mass or less, more preferably 0.4 parts by mass or less, and particularly preferably 0.3 parts by mass or less.

When the silane coupling agent is contained in the polyol component, the silane coupling agent is, for example, 0.3 parts by mass or more, preferably 0.5 part by mass, based on 100 parts by mass of the total amount of the polyol component. More than 40 parts by mass, for example, 40 parts by mass or less, preferably 20 parts by mass or less, more preferably 10 parts by mass or less, still more preferably 5 parts by mass or less, still more preferably 1.5 parts by mass or less, in particular. It is preferably 1.0 part by mass or less.

If the two-component curable solvent-free adhesive contains the silane coupling agent in the above ratio, the content resistance can be further improved, and further, excellent boil resistance can be obtained. In particular, if both the content ratio of the silane coupling agent and the content ratio of phosphoric acid are adjusted to the above ranges, it is possible to improve the content resistance to citrus fruit juice (orange juice, etc.). can.

Further, one or both of the polyisocyanate component and the polyol component may contain, for example, a defoaming agent, an epoxy resin, a catalyst, a coatability improver, a leveling agent, and a stabilizer (antioxidant, if necessary). Additives such as UV absorbers), plasticizers, surfactants, pigments, fillers, organic or inorganic fine particles, and antifungal agents can be appropriately added.

The blending amount of the additive is appropriately determined depending on the purpose and use thereof.

In the two-component curable solvent-free adhesive, the above-mentioned polyol component (main agent) and the above-mentioned polyisocyanate component (curing agent) are prepared and blended at the time of use.

The blending ratio of the polyisocyanate component and the polyol component is, for example, 0.5 or more as the equivalent ratio (NCO / OH) of the isocyanate group of the polyisocyanate component to the hydroxyl group of the polyol component from the viewpoint of improving the adhesiveness. It is preferably 0.6 or more, for example, 5 or less, preferably 3 or less.

Further, the mixing ratio of the polyisocyanate component and the polyol component is such that the polyol component is, for example, 30 parts by mass or more, preferably 40 parts by mass or more, and for example, 100 parts by mass or less with respect to 100 parts by mass of the polyisocyanate component. It is preferably 80 parts by mass or less, more preferably 70 parts by mass or less.

Then, the two-component curable solvent-free adhesive is formulated as described above, and then coated on the adherend by a known laminator.

Examples of the adherend include a plastic film and a barrier layer.

That is, the two-component curable solvent-free adhesive is used as a laminating adhesive for laminating a plastic film or a barrier layer to produce a composite film.

Preferably, the two-component curable solvent-free adhesive is used for adhering the plastic film and the barrier film.

Examples of the plastic film include olefin polymers (for example, polyethylene, polypropylene, etc.), polyester polymers (for example, polyalkylene terephthalates such as polyethylene terephthalate and polybutylene terephthalate, polyalkylene naphthalates, and their polyalkylene allylates. Unit-based copolyester, etc.), polyamide-based polymer (eg, nylon 6, nylon 66, etc.), vinyl-based polymer (eg, polyvinyl chloride, ethylene-vinyl acetate copolymer, ethylene-vinyl alcohol) Examples thereof include a film made of a polymer such as (polymer, etc.).

Examples of the plastic film include a film made of an olefin polymer, and more preferably a polyethylene film and a polypropire film.

As the plastic film, either an unstretched film (unstretched polyethylene, unstretched polypropylene, etc.) or a uniaxially or biaxially stretched film (biaxially stretched polypropylene, biaxially stretched polyalkylene terephthalate, nylon, etc.) is used. Can be done.

The plastic film preferably includes an unstretched film, and more preferably an unstretched polyethylene film and an unstretched polypropylene film.

Further, the plastic film can be prepared as various coextruded films or a composite film in which plastic films are previously bonded to each other.

The thickness of the plastic film is not particularly limited, but is, for example, 5 μm or more, preferably 10 μm or more, and for example, 200 μm or less, preferably 100 μm or less.

The barrier film is a film having a barrier property against gas or liquid, and examples thereof include a metal film and an inorganic vapor-deposited film.

Examples of the metal film include a metal foil made of aluminum, stainless steel, iron, copper, lead and the like. The metal film preferably includes a metal foil made of aluminum.

The thickness of the metal film is, for example, 5 μm or more, preferably 10 μm or more, for example, 100 μm or less, preferably 20 μm or less, and more preferably 15 μm or less.

The inorganic vapor-deposited film is a plastic film in which an inorganic layer is vapor-deposited on at least one surface.

The inorganic layer can be formed by vapor deposition, sputtering, a sol-gel method, or the like. The inorganic layer is made of, for example, a simple substance such as titanium, aluminum, or silicon, or an inorganic compound (oxide or the like) containing an element thereof. Preferably, a vapor-deposited film obtained by vapor-depositing alumina alone, silica alone, or both alumina and silica can be mentioned.

Further, in the inorganic vapor-deposited film, examples of the plastic film on which the inorganic layer is vapor-deposited include the same as above, and specifically, an olefin-based polymer, a polyester-based polymer, a polyamide-based polymer, and a vinyl-based heavy weight. Examples thereof include a film made of a polymer such as a coalescence. As the plastic film on which the inorganic layer is vapor-deposited, a film made of a polyester-based polymer is preferable, and a film made of polyethylene terephthalate is more preferable.

The inorganic vapor-filmed film is formed by a combination of the above-mentioned inorganic layer and the above-mentioned plastic film. The inorganic vapor-deposited film preferably includes a polyethylene terephthalate film on which alumina is vapor-deposited.

As the barrier film, an inorganic vapor-deposited film is preferable.

When an inorganic thin-film film is used as the barrier film, the surface to be attached to the plastic film may be either one surface (inorganic layer) or the other surface (plastic film) of the inorganic vapor-film film. Preferably, the inorganic layer in the inorganic vapor deposition film is attached to the plastic film.

In addition, the plastic film and the barrier film can have an overcoat layer, if necessary. Further, the plastic film and the barrier film may be subjected to various treatments such as corona discharge treatment and primer treatment, if necessary.

Then, a laminated film is obtained by adhering these films (plastic film, barrier film, etc.) via an adhesive layer made of the above-mentioned two-component curable solvent-free adhesive.

More specifically, in the production of a laminated film, first, an adhesive containing a polyisocyanate component and a polyol component is applied to the surface of either a plastic film or a barrier film.

Then, the coated surface is attached to the surface of the other barrier film or plastic film, and then cured and cured at room temperature or under heating.

As the laminated film, a barrier film and a plastic film may be attached (primary laminating) to prepare a primary laminated composite film, and further, another surface may be formed on at least one surface of the primary laminated composite film. It is also possible to attach a plastic film (secondary laminating) to produce a secondary laminating composite film.

In primary laminating, usually either one of the barrier film or the plastic film is sent out from the sending roll, the other is attached, wound on the winding roll, and if necessary, heated and cured (for example, 25 to 60). Curing at ℃).

In the secondary laminating, usually, the primary laminating composite film is sent out from the winding roll, another plastic film is attached, the film is wound on the winding roll, and if necessary, it is heated and cured.

In the production of the secondary laminating composite film, the two-component curable solvent-free adhesive of the present invention may be used in both the primary laminating and the secondary laminating, or the primary laminating and the secondary laminating may be used. It is also possible to use the two-component curable solvent-free adhesive of the present invention in either one and the other adhesive in the other.

The laminating temperature (coating temperature) is, for example, 35 ° C. or higher, preferably 40 ° C. or higher. If it can be laminated, there is no upper limit of temperature, but it is usually 100 ° C. or lower, preferably 90 ° C. or lower, and more preferably 85 ° C. or lower.

Further, at the time of laminating (coating), for example, the adhesive can be heated to adjust the viscosity to an appropriate level. When heating, the temperature is, for example, 35 to 100 ° C, preferably 35 to 90 ° C, and more preferably 40 to 80 ° C. The viscosity of the adhesive in that case is, for example, 4000 to 8000, preferably 5000 to 7500 at 50 ° C. If the heating is set to 100 ° C. or lower, the reaction between the polyisocyanate component and the polyol component can be suppressed before coating, so that excessive thickening can be prevented and good workability can be ensured.

The amount of the two-component curable solvent-free adhesive applied is, for example, 0.5 to 5 g / m ² , preferably 1 to 5 g / m ² , and more preferably 1.5 to 4 in each laminating step. It is .5 g / m ² .

Further, as the laminating device in which the two-component curing type solvent-free adhesive is used, either a forward transfer type coating device or a reverse transfer type coating device (reverse coater) can be used.

Such a two-component curable solvent-free adhesive contains a polyisocyanate component and a polyol component, and further contains unreacted diphenylmethane diisocyanate and phosphoric acid in a predetermined ratio.

Therefore, the above-mentioned two-component curable solvent-free adhesive has excellent production efficiency, has an appropriate pot life, can suppress appearance defects, has excellent low-temperature curability, and has excellent content resistance. Can produce excellent laminated films.

Therefore, according to the two-component curable solvent-free adhesive of the present invention, laminated films in various industrial fields such as foods, beverages, pharmaceuticals and quasi-drugs can be suitably obtained.

Further, the present invention is a laminate film (primary laminate film, secondary laminate film, etc.) obtained by using the above-mentioned two-component curable solvent-free adhesive, that is, the above-mentioned two-component curable solvent-free adhesive. Includes a laminated film with an adhesive layer consisting of.

Since such a laminated film contains an adhesive layer made of the above-mentioned two-component curable solvent-free adhesive, it is excellent in production efficiency, appearance and content resistance.

Next, the present invention will be described with reference to Examples and Comparative Examples, but the present invention is not limited to the following examples. In addition, "part" and "%" are based on mass unless otherwise specified. In addition, specific numerical values such as the compounding ratio (content ratio), physical property values, parameters, etc. used in the following description are the compounding ratios corresponding to them described in the above-mentioned "form for carrying out the invention" (forms for carrying out the invention). Substitute the upper limit value (value defined as "less than or equal to" or "less than") or the lower limit value (value defined as "greater than or equal to" or "excess") such as content ratio), physical property value, parameter, etc. be able to.

<Polyisocyanate component>
Production Example 1 (Production of Polyesterdiol A)
614 g of adipic acid, 477 g of neopentyl glycol, and 87 g of propylene glycol were charged into a reactor and subjected to an esterification reaction at 160 to 220 ° C. under a nitrogen stream.

Then, after distilling the predetermined water, 0.01 g of tin octylate was added as a catalyst, and the esterification reaction was carried out at 180 to 220 ° C. under a nitrogen stream to obtain polyester diol A.

The polyester diol A had an average number of functional groups of 2.0, a hydroxyl group equivalent of 400, and a number average molecular weight of 800.

Production Example 2 (Production of Polyisocyanate Component A-1)
Polyester diol A 110 g, polypropylene glycol (trade name D-1000, molecular weight 1000, manufactured by Mitsui Kagaku SKC Polyurethane (hereinafter the same)) 320 g, and luplanate MI (liquid diphenylmethane diisocyanate (MDI), manufactured by BASF (hereinafter the same)) 571 g. Was charged into a reactor and subjected to a urethanization reaction at 70 to 80 ° C. under a nitrogen stream to obtain a polyisocyanate component A-1.

The unreacted diphenylmethane diisocyanate concentration (theoretical concentration) in the polyisocyanate component A-1 was 34.3%, and the isocyanate group equivalent (based on JIS K 1603-1 (2007) A method (hereinafter the same)) was 274. rice field.

Production Example 3 (Production of Polyisocyanate Component A-2)
116 g of polyester diol A, 339 g of D-1000 (polypropylene glycol, molecular weight 1000), and 544 g of ruplanate MI (diphenylmethane diisocyanate) were charged in a reactor and subjected to a urethanization reaction at 70 to 80 ° C. under a nitrogen stream to cause a polyisocyanate component A-2. Got

The unreacted diphenylmethane diisocyanate concentration (theoretical concentration) in the polyisocyanate component A-2 was 30.3%, and the isocyanate group equivalent was 295.

Production Example 4 (Production of Polyisocyanate Component A-3)
94 g of polyester diol A, 273 g of D-1000 (polypropylene glycol, molecular weight 1000), and 633 g of ruplanate MI (diphenylmethane diisocyanate) were charged in a reactor and subjected to a urethanization reaction at 70 to 80 ° C. under a nitrogen stream to cause a polyisocyanate component A-3. Got

The unreacted diphenylmethane diisocyanate concentration (theoretical concentration) in the polyisocyanate component A-3 was 43.9%, and the isocyanate group equivalent was 233.

Production Example 5 (Production of Polyisocyanate Component A-4)
124 g of polyester diol A, 361 g of D-1000 (polypropylene glycol, molecular weight 1000), and 515 g of ruplanate MI (diphenylmethane diisocyanate) were charged in a reactor and subjected to a urethanization reaction at 70 to 80 ° C. under a nitrogen stream to cause a polyisocyanate component A-4. Got

The unreacted diphenylmethane diisocyanate concentration (theoretical concentration) in the polyisocyanate component A-4 was 25.8%, and the isocyanate group equivalent was 323.

Production Example 6 (Production of Polyisocyanate Component A-5)
82 g of polyester diol A, 238 g of D-1000 (polypropylene glycol, molecular weight 1000), and 680 g of ruplanate MI (diphenylmethane diisocyanate) were charged in a reactor and subjected to a urethanization reaction at 70 to 80 ° C. under a nitrogen stream to cause a polyisocyanate component A-5. Got

The unreacted diphenylmethane diisocyanate concentration (theoretical concentration) in the polyisocyanate component A-5 was 51.0%, and the isocyanate group equivalent was 210.

Table 1 shows the compounding formulation of each polyisocyanate component and the equivalent ratio R (NCO / OH) of the isocyanate group in the diphenylmethane diisocyanate to the hydroxyl group in the polyol.

Production Example 7 (Production of Polyisocyanate Component A-6)
124 g of polyester diol A, 361 g of D-1000 (polypropylene glycol, molecular weight 1000), and 515 g of TDI (toluene diisocyanate) were charged in a reactor and subjected to a urethanization reaction at 70 to 80 ° C. under a nitrogen stream. Then, the unreacted toluene diisocyanate was removed upstream of the thin film to obtain a polyisocyanate component A-6.

The unreacted toluene diisocyanate (TDI) concentration (theoretical concentration) in the polyisocyanate component A-6 was 0.1%, and the isocyanate group equivalent was 574.

Table 1 shows the compounding formulation of each polyisocyanate component and the equivalent ratio R (NCO / OH) of the isocyanate group in the diphenylmethane diisocyanate to the hydroxyl group in the polyol.

<Polycarbonate component>
Production Example 8 (Production of Polyesterdiol B)
221 g of phthalic acid, 327 g of adipic acid, and 587 g of diethylene glycol were charged into a reactor and subjected to an esterification reaction at 160 to 220 ° C. under a nitrogen stream.

Then, after distilling the predetermined water, 0.01 g of tin octylate was added as a catalyst, and the esterification reaction was carried out at 180 to 220 ° C. under a nitrogen stream to obtain polyester diol B.

The polyester diol B had an average number of functional groups of 2.0, a hydroxyl group equivalent of 375, and a number average molecular weight of 700.

Production Example 9 (Production of polyol component B-1)
980 g of polyester diol B and 10 g of trimethylolpropane were charged into a reactor, and the mixture was stirred and mixed at 80 ° C. under a nitrogen stream for 60 minutes.

Then, the temperature is lowered to 60 ° C., 9 g of 3- (trimethoxysilyl) propylglycidyl ether (silane coupling agent) and 0.45 g of orthophosphoric acid (hereinafter, simply referred to as phosphoric acid) are added, and the mixture is stirred and mixed for 30 minutes. The polyol component B-1 was obtained.

Production Example 10 (Production of polyol component B-2)
980 g of polyester diol B and 10 g of glycerin were charged into a reactor, and the mixture was stirred and mixed at 80 ° C. under a nitrogen stream for 60 minutes.

Then, the temperature is lowered to 60 ° C., 9 g of 3- (trimethoxysilyl) propylglycidyl ether (silane coupling agent) and 0.45 g of orthophosphoric acid (hereinafter, simply referred to as phosphoric acid) are added, and the mixture is stirred and mixed for 30 minutes. The polyol component B-2 was obtained.

Production Example 11 (Production of polyol component B-3)
980 g of polyester diol B and 10 g of trimethylolpropane were charged into a reactor, and the mixture was stirred and mixed at 80 ° C. under a nitrogen stream for 60 minutes.

Then, the temperature is lowered to 60 ° C., 4.5 g of 3- (trimethoxysilyl) propylglycidyl ether (silane coupling agent) and 0.45 g of phosphoric acid are added, and the mixture is stirred and mixed for 30 minutes, and the polyol component B-3 is added. Got

Production Example 12 (Production of polyol component B-4)
980 g of polyester diol B and 10 g of trimethylolpropane were charged into a reactor, and the mixture was stirred and mixed at 80 ° C. under a nitrogen stream for 60 minutes.

Then, the temperature is lowered to 60 ° C., 97.9 g of 3- (trimethoxysilyl) propylglycidyl ether (silane coupling agent) and 0.49 g of phosphoric acid are added, and the mixture is stirred and mixed for 30 minutes to obtain the polyol component B-4. Obtained.

Production Example 13 (Production of polyol component B-5)
980 g of polyester diol B and 10 g of trimethylolpropane were charged into a reactor, and the mixture was stirred and mixed at 80 ° C. under a nitrogen stream for 60 minutes.

Then, the temperature is lowered to 60 ° C., 9 g of 3- (trimethoxysilyl) propylglycidyl ether (silane coupling agent) and 0.85 g of phosphoric acid are added, and the mixture is stirred and mixed for 30 minutes to obtain polyol component B-5. rice field.

Production Example 14 (Production of polyol component B-6)
980 g of polyester diol B and 10 g of trimethylolpropane were charged into a reactor, and the mixture was stirred and mixed at 80 ° C. under a nitrogen stream for 60 minutes.

Then, the temperature is lowered to 60 ° C., 9 g of 3- (trimethoxysilyl) propylglycidyl ether (silane coupling agent) and 0.30 g of phosphoric acid are added, and the mixture is stirred and mixed for 30 minutes to obtain polyol component B-6. rice field.

Production Example 15 (Production of polyol component B-7)
980 g of polyester diol B and 10 g of trimethylolpropane were charged into a reactor, and the mixture was stirred and mixed at 80 ° C. under a nitrogen stream for 60 minutes.

Then, the temperature is lowered to 60 ° C., 9 g of 3- (trimethoxysilyl) propylglycidyl ether (silane coupling agent) and 0.10 g of phosphoric acid are added, and the mixture is stirred and mixed for 30 minutes to obtain polyol component B-6. rice field.

Production Example 16 (Production of polyol component B-8)
980 g of polyester diol B and 10 g of trimethylolpropane were charged into a reactor, and the mixture was stirred and mixed at 80 ° C. under a nitrogen stream for 60 minutes.

Then, the temperature is lowered to 60 ° C., 9 g of 3- (trimethoxysilyl) propylglycidyl ether (silane coupling agent) and 1.0 g of phosphoric acid are added, and the mixture is stirred and mixed for 30 minutes to obtain polyol component B-8. rice field.

Production Example 17 (Production of polyol component B-9)
980 g of polyester diol B and 10 g of trimethylolpropane were charged into a reactor, and the mixture was stirred and mixed at 80 ° C. under a nitrogen stream for 60 minutes.

Then, the temperature is lowered to 60 ° C., 9 g of 3- (trimethoxysilyl) propylglycidyl ether (silane coupling agent) and 0.05 g of phosphoric acid are added, and the mixture is stirred and mixed for 30 minutes to obtain polyol component B-9. rice field.

Production Example 18 (Production of polyol component B-10)
980 g of polyester diol B and 10 g of trimethylolpropane were charged into a reactor, and the mixture was stirred and mixed at 80 ° C. under a nitrogen stream for 60 minutes.

Then, the temperature is lowered to 60 ° C., 533 g of 3- (trimethoxysilyl) propylglycidyl ether (silane coupling agent) and 0.69 g of orthophosphoric acid (hereinafter, simply referred to as phosphoric acid) are added, and the mixture is stirred and mixed for 30 minutes. The polyol component B-10 was obtained.

The formulation of each polyol component is shown in Table 2.

<Two-component curable solvent-free adhesive>
By combining each polyisocyanate component and each polyol component obtained above in a predetermined number of parts (parts by mass), a two-component curable solvent-free adhesive of each Example and each Comparative Example was prepared.

Further, the unreacted diphenylmethane diisocyanate (MDI) concentration, the phosphoric acid concentration, and the silane coupling agent concentration in the obtained two-component curable solvent-free adhesive were calculated based on the blending ratio. Further, these two-component curable solvent-free adhesives were used to measure the change in the viscosity of the compounding liquid over time, and the results are shown in Tables 3 to 6.

Evaluation Using each two-component curable solvent-free adhesive, composite films were prepared by the methods described below, and then the physical characteristics of each composite film were evaluated.

The results are shown in Tables 3 to 6.

<Preparation of composite film A>
Two liquids by mixing 10 parts by weight of Takelac A-310 (polyol component, manufactured by Mitsui Chemicals) and 1 part by weight of Takenate A-3 (polyisocyanate component, manufactured by Mitsui Chemicals) and diluting with ethyl acetate. A mold organic solvent-based adhesive was prepared.

Then, a polyethylene terephthalate film (thickness 12 μm, Lumirer P60, manufactured by Toray Film Processing Co., Ltd.) and an aluminum foil (thickness 9 μm, manufactured by Toyo Aluminum K.K.) are first laminated with a two-component organic solvent-based adhesive. A laminated composite film was produced.

Next, using a solvent-free laminator (non-sol laminator TNS-400-200 manufactured by Okazaki Machinery Co., Ltd.) on the surface of the aluminum foil of the primary laminated composite film (A), the two liquids of each example and each comparative example are used. A curable solvent-free adhesive was applied (coating temperature 50 ° C., coating amount of about 2.0 g / m ² , coating speed of 150 m / min).

Then, an unstretched polyethylene film (thickness 40 μm, linear low-density polyethylene film TUX-HC (manufactured by Mitsui Chemicals Toshiro Co., Ltd.)) was bonded to the coated surface to prepare a laminated composite film A. Then, the laminated composite film A was cured at 40 ° C. for 2 days to cure the two-component curable solvent-free adhesive.

<Evaluation: Orange juice resistance test>
Using the laminated composite film A obtained as described above, a bag having a size of 6.5 × 17.5 cm was produced. The bag was prepared by heat sealing, and the unstretched polyethylene film was on the inside and the polyethylene terephthalate film was on the outside.

The bag was filled with ponjuice (100% fruit juice) as the content. After storing the bag in a thermostat at 50 ° C. for 2 weeks, the contents were taken out, and the adhesive strength between the aluminum foil and the unstretched polyethylene film was measured in an environment of 25 ° C., a test piece width of 15 mm, a tensile speed of 300 mm / min, and so on. It was measured by a T-type peeling test. The results are shown in Tables 3 to 6.

Tables 3 to 6 also show the state of the laminated composite film A after the T-type peeling test. Specifically, "PE Nobi" indicates that the unstretched polyethylene film was stretched after the test, and "AL / Ad" indicates that the unstretched polyethylene film was peeled off between the aluminum foil and the adhesive layer.

Similarly, the heat seal strength was measured. The results are shown in Tables 3 to 6.

Tables 3 to 6 also show the state of the laminated composite film A after the heat seal strength test. Specifically, "Film gilet" means that the unstretched polyethylene film was cut after the test, and "△ peeling" means that the unstretched polyethylene film was peeled off from the adhesive layer and floated like a square mountain. Show that.

<Preparation of composite film B>
Aluminum-deposited polyethylene terephthalate (PET) film (thickness 12 μm, VMPET, manufactured by Toray Film Processing Co., Ltd.) using a solvent-free laminator (manufactured by Okazaki Kikai Kogyo Co., Ltd., non-sol laminator TNS-400-200) on the aluminum vapor-deposited surface. The two-component curable solvent-free adhesive of Examples and Comparative Examples was applied (coating temperature 50 ° C., coating amount of about 1.5 g / m ² , coating speed of 150 m / min). Then, a polyethylene terephthalate film (thickness 12 μm, E-5102, manufactured by Toray Film Processing Co., Ltd.) was bonded to the coated surface to prepare a primary laminated composite film (B).

Next, a solvent-free laminator (manufactured by Okazaki Kikai Kogyo Co., Ltd., non-sol laminator TNS-400-200) was used on the back surface of the primary laminated composite film (B) E-5102, and each example and each comparative example were used. A liquid-curable solvent-free adhesive was applied (coating temperature 50 ° C., coating amount of about 2.0 g / m2, coating speed of 150 m / min).

Then, an unstretched polyethylene film (thickness 40 μm, linear low-density polyethylene film TUX-HC (manufactured by Mitsui Chemicals Toshiro Co., Ltd.)) was bonded to the coated surface to prepare a laminated composite film B. Then, the laminated composite film B was cured at 40 ° C. for 2 days to cure the two-component curable solvent-free adhesive.

<Evaluation: Content resistance (alkali) resistance test>
Using the laminated composite film B obtained as described above, a bag having a size of 6.5 × 17.5 cm was produced. The bag was prepared by heat sealing, and the unstretched polyethylene film was on the inside and the aluminum-deposited polyethylene terephthalate film was on the outside.

The bag was filled with Kao Attack (weakly alkaline liquid detergent) as the contents. After storing the bag in a thermostat at 50 ° C. for 2 weeks, the contents were taken out, and the adhesive strength between the polyethylene terephthalate film (E-5102) and the unstretched polyethylene film was measured in a 25 ° C. environment with a test piece width of 15 mm. It was measured by a T-type peeling test with a tensile speed of 300 mm / min. The results are shown in Tables 3 to 6.

Similarly, the heat seal strength was measured. The results are shown in Tables 3 to 6.

Tables 3 to 6 also show the state of the laminated composite film B after the T-type peeling test. Specifically, "PET surface layer peeling" means that the adhesive layer and the unstretched polyethylene film are peeled off on the surface layer of the polyethylene terephthalate film (E-5102).

Similarly, the heat seal strength was measured. The results are shown in Tables 3 to 6.

Tables 3 to 6 also show the state of the laminated composite film B after the heat seal strength test. Specifically, "Film gilet" indicates that the unstretched polyethylene film was cut after the test.

<Evaluation: Coating appearance>
The laminated appearance of the primary laminated composite film (B) obtained as described above was observed and evaluated according to the following criteria.
◯: No bubbles and / or yuzu skin were confirmed, and the appearance was good.
Δ: Very few bubbles were confirmed.
X: Significant air bubbles and / or citron skin were confirmed.

<Preparation of composite film C>
Each example and each comparison using a solvent-free laminator (Non-sol laminator TNS-400-200, manufactured by Okazaki Kikai Kogyo Co., Ltd.) on the inner surface of a nylon (NY) film (thickness 15 μm, emblem ONBC, manufactured by Unitika Ltd.). The example two-component curable solvent-free adhesive was applied (coating temperature 50 ° C., coating amount about 1.5 g / m ² , coating speed 150 m / min). Then, an unstretched polyethylene film (thickness 40 μm, linear low-density polyethylene film TUX-HC (manufactured by Mitsui Chemicals Toshiro Co., Ltd.)) was bonded to the coated surface to prepare a laminated composite film C. Then, the laminated composite film C was cured at 40 ° C. for 2 days to cure the two-component curable solvent-free adhesive.

<Evaluation: Content resistance (boil) resistance test>
Using the laminated composite film C obtained as described above, a bag having a size of 6.5 × 17.5 cm was produced. The bag was prepared by heat sealing, and the unstretched polyethylene film was on the inside and the nylon film was on the outside.

The bag was filled with water / oil (volume ratio 9/1) as the contents. The bag was boiled in hot water at 100 ° C. for 30 minutes, then the contents were taken out, and the adhesive strength between the nylon / unstretched polyethylene film was adjusted to a test piece width of 15 mm and a tensile speed of 300 mm / min under a 25 ° C. environment. It was measured by a T-type peeling test. The results are shown in Tables 3 to 6.

Similarly, the heat seal strength was measured. The results are shown in Tables 3 to 6.

Tables 3 to 6 also show the state of the laminated composite film C after the T-type peeling test. Specifically, "PE cut" indicates that the unstretched polyethylene film was cut after the test, and "NY / ad" means that the nylon film and the adhesive interface were peeled off after the test. ..

Similarly, the heat seal strength was measured. The results are shown in Tables 3 to 6.

Tables 3 to 6 also show the state of the laminated composite film C after the heat seal strength test. Specifically, "PE / PE" indicates that the unstretched polyethylene films were peeled off after the test.

<Evaluation: Coating appearance>
The laminated appearance of the primary laminated composite film (C) obtained as described above was observed and evaluated according to the following criteria.
◯: No bubbles and / or yuzu skin were confirmed, and the appearance was good.
Δ: Very few bubbles were confirmed.
X: Significant air bubbles and / or citron skin were confirmed.

The above invention has been provided as an exemplary embodiment of the present invention, but this is merely an example and should not be construed in a limited manner. Modifications of the present invention that are apparent to those skilled in the art are included in the claims below.

The two-component curable solvent-free adhesive and laminated film of the present invention can be suitably used in various industrial fields such as foods, beverages, pharmaceuticals and quasi-drugs.

Claims (3)

A two-component curable solvent-free adhesive containing a polyisocyanate component, a polyol component , and a silane coupling agent .
The polyisocyanate component is
It contains diphenylmethane diisocyanate and an isocyanate group-terminated prepolymer which is a reaction product of a polyol, and unreacted diphenylmethane diisocyanate.
The polyol component is
It contains a polyester polyol having a number average molecular weight of 1000 or less and an alcohol having a trivalent value or more .
The unreacted diphenylmethane diisocyanate is 20 parts by mass or more and 30 parts by mass or less with respect to 100 parts by mass of the two-component curing type solventless adhesive.
The silane coupling agent is 0.1 part by mass or more and 15 parts by mass or less with respect to 100 parts by mass of the two-component curing type solventless adhesive.
The amount of the trivalent or higher alcohol is 0.1 parts by mass or more and 10 parts by mass or less with respect to 100 parts by mass of the polyol component.
The two-component curable solvent-free adhesive is characterized by containing 0.003 parts by mass or more and 0.030 parts by mass or less of phosphoric acid with respect to 100 parts by mass of the total amount of the two-component curable solvent-free adhesive. glue. The first aspect of the present invention is characterized in that the silane coupling agent is contained in an amount of 0.2 parts by mass or more and 5.0 parts by mass or less with respect to 100 parts by mass of the total amount of the two-component curing type solventless adhesive. The described two-component curable solvent-free adhesive. A laminated film comprising an adhesive layer made of the two-component curable solvent-free adhesive according to claim 1 or 2 .