JP2019044005A - Moisture-curable hot melt adhesive and laminate - Google Patents

Abstract

To provide a moisture-curable adhesive capable of improving adhesive strength while maintaining moisture permeability.SOLUTION: The moisture-curable adhesive comprises a urethane prepolymer with an isocyanate group. The urethane prepolymer with the isocyanate group is a reaction product of a polyol (A) and a polyisocyanate (B). The polyol (A) comprises a polycarbonate polyol (a1) having a unit derived from a compound (d1) represented by general formula (1). [In general formula (1), n represents an integer from 2 to 7 inclusive.]SELECTED DRAWING: None

Description

  The present invention relates to a moisture-curable hot melt adhesive and a laminate obtained using the same.

  BACKGROUND ART Organic solvent-based resin compositions are conventionally used in various fields as, for example, adhesives and pressure-sensitive adhesives. However, since the organic solvent-based resin composition contains a large amount of organic solvent, it is harmful to human body, danger of ignition, environmental pollution such as water quality and air, productivity decline due to drying, recovery loss of solvent There were various problems such as energy burden for solvent recovery.

  Therefore, various solvent-free resin compositions have been studied as adhesives in place of organic solvent-based resin compositions. Among them, the moisture-curable urethane adhesive has excellent adhesion and is easy to adjust the adhesion time, and therefore, it is noted as being suitable for molding processing such as adhesion processing and sealing work requiring continuous production. Are collecting As such a moisture-curable urethane adhesive, for example, a polyester polyol obtained by reacting a polyol obtained by adding an alkylene oxide to bisphenol A, an aliphatic polycarboxylic acid and an aromatic polycarboxylic acid, a crystalline polyester polyol, and 2, A moisture-curable adhesive containing a urethane prepolymer obtained by reacting a polyisocyanate containing a polyoxyethylene glycol having a number average molecular weight of 000 to 25,000 with a polyisocyanate has been proposed (see Patent Document 1). )

Patent No. 4240158

  However, in the case of the conventionally known moisture-curable adhesive, the higher the moisture permeability, the lower the adhesive strength in some cases.

  An object of the present invention is to provide a moisture-curable adhesive capable of improving adhesive strength while maintaining moisture permeability.

  The present invention is a moisture-curable adhesive comprising a urethane prepolymer having an isocyanate group, wherein the urethane prepolymer having an isocyanate group is a reaction product of a polyol (A) and a polyisocyanate (B), The present invention relates to a moisture-curable adhesive wherein the polyol (A) comprises a polycarbonate polyol (a1) having a unit derived from a hydroxy compound (d1) represented by the general formula (1).

［一般式（１）中、ｎは、２以上７以下の整数を表す。］

[In general formula (1), n represents an integer of 2 or more and 7 or less. ]

  According to the moisture-curable adhesive of the present invention, it is possible to provide a cured product with improved adhesive strength while maintaining the moisture permeability.

  The moisture curable adhesive of the present invention comprises a urethane prepolymer having an isocyanate group. The isocyanate group is preferably present at the end of the urethane prepolymer having the isocyanate group. The urethane prepolymer having an isocyanate group is a reaction product of a polyol (A) and a polyisocyanate (B). The polyol (A) is a compound having two or more hydroxyl groups, and includes a polycarbonate polyol (a1) having a unit derived from a hydroxy compound (D).

The content of the polycarbonate polyol (a1) is preferably 10% by mass or more, more preferably 15% by mass or more, still more preferably 20% by mass or more, and 100% by mass or less in the polyol (A), preferably Is 90 mass% or less.
The hydroxy compound (D) is a compound having two or more hydroxy groups. As the hydroxy compound (D), one or more species can be used. For example, ethylene glycol, propylene glycol, butanediol, pentanediol, hexanediol, diethylene glycol, dipropylene glycol, triethylene glycol, tripropylene Diols such as glycol, polyethylene glycol and polypropylene glycol; and polyols such as trimethylolmethane, trimethylolpropane, ditrimethylolpropane, pentaerythritol and dipentaerythritol.

In particular, the hydroxy compound (D) includes the hydroxy compound (d1) represented by the general formula (1). The polycarbonate polyol (a1) is a unit derived from a hydroxy compound represented by the general formula (1) (d1) (-O - (- (CH 2) 2 O-) n -) By including the obtained Both moisture permeability and heat resistance of the cured product can be achieved.

［一般式（１）中、ｎは、２以上７以下の整数を表す。］

[In general formula (1), n represents an integer of 2 or more and 7 or less. ]

  As the hydroxy compound (d1), one or more species can be used, and examples thereof include diethylene glycol, triethylene glycol, polyethylene glycol (preferably having a molecular weight of 160 to 360, more preferably a molecular weight of 190 to 330), etc. Be Among them, diethylene glycol and triethylene glycol are preferable from the viewpoint of further excellent moisture permeability and heat resistance.

  The content rate of the hydroxy compound (d1) is preferably 40% by mass or more, more preferably 60% by mass or more, preferably 100% by mass or less, more preferably 99% by mass in 100% by mass of the hydroxy compound (D) % Or less. When the content of the hydroxy compound (d1) is in the above range, the adhesive strength can be improved while maintaining the moisture permeability of the obtained cured product.

  Among them, the hydroxy compound (d1) preferably contains triethylene glycol and / or polyethylene glycol. In this case, the content of triethylene glycol and / or polyethylene glycol is preferably 100% by mass of the hydroxy compound (d1). Is 10% by mass or more, more preferably 20% by mass or more, preferably 100% by mass or less, more preferably 99% by mass or less. When the content of triethylene glycol and / or polyethylene glycol is in the above range, the adhesive strength can be highly improved while maintaining the moisture permeability of the obtained cured product.

  When the hydroxy compound (D) contains another hydroxy compound other than the hydroxy compound (d1), as the other hydroxy compound, butanediol, trimethylolol from the viewpoint of improving the adhesive strength while maintaining the moisture permeability. Propane is preferred.

The polycarbonate polyol (a1) can be produced by reacting the hydroxy compound (D) and the carbonate compound (E) in the presence of a polycarbonateation or transesterification catalyst which is optionally used.
In the reaction, titanium compounds such as titanium alcoholates such as tetramethyltitanate, tetraisopropyltitanate and tetrabutyltitanate, titanium phenolates such as tetraphenyltitanate may be allowed to coexist as a polycarbonateation or transesterification catalyst. A metal catalyst, an acid catalyst or the like may be used as the polycarbonate or ester catalyst.
The amount of the polycarbonateed or transesterification catalyst is preferably 0.001 parts by mass or more, more preferably 0.05 parts by mass or more, based on 100 parts by mass of the total of the hydroxy compound (D) and the carbonate compound (E). Preferably it is 1 mass part or less, More preferably, it is 0.5 mass part or less, More preferably, it is 0.3 mass part or less.
Further, as the polycarbonate polyol (a1), one obtained by using a known production method such as one obtained by reacting the hydroxy compound (D) with phosgene can be used.

  As said carbonate compound (E), 1 type (s) or 2 or more types can be used, For example, aliphatic carbonate and aromatic ring containing carbonate are mentioned. As aliphatic carbonates, saturated aliphatic carbonates such as dimethyl carbonate, diethyl carbonate, ethyl methyl carbonate, di-n-butyl carbonate, diisobutyl carbonate, ethyl n-butyl carbonate, ethyl isobutyl carbonate, etc .; ethylene carbonate, trimethylene carbonate, Tetramethylene carbonate, 1,2-propylene carbonate, 1,2-butylene carbonate, 1,3-butylene carbonate, 2,3-butylene carbonate, 1,2-pentylene carbonate, 1,3-pentylene carbonate, 1, Unsaturated aliphatic carbonates such as 4-pentylene carbonate, 1,5-pentylene carbonate, 2,3-pentylene carbonate and 2,4-pentylene carbonate It is below. Examples of the aromatic ring-containing carbonate include diphenyl carbonate and dibenzyl carbonate. Among them, saturated aliphatic carbonates such as dimethyl carbonate, ethyl methyl carbonate and diethyl carbonate; and aromatic carbonates such as diphenyl carbonate are preferable because urethane resin molded products having excellent chemical resistance can be obtained.

  The number average molecular weight of the polycarbonate polyol (a1) is preferably 500 or more, more preferably 1,000 or more, preferably 8,000 or less, more preferably 6,000 or less.

  The hydroxyl value of the polycarbonate polyol (a1) is preferably 10 mg KOH / g or more, more preferably 20 mg KOH / g or more, preferably 210 mg KOH / g or less, more preferably 120 mg KOH / g or less. The hydroxyl value is defined as the number of mg of potassium hydroxide corresponding to the hydroxyl group in 1 g of polycarbonate polyol, and represents a value measured in accordance with JIS K 1551-1: 2007.

The said polyol (A) is a compound which has a 2 or more hydroxyl group, and the range which does not impair the effect of this invention may contain the polyalkylene polyol (a2) which has an oxyethylene unit. The oxyethylene units _{(-O-CH 2 CH 2 -} ) polyalkylene polyol (a2) containing a may be a homopolymer consisting only of oxyethylene units, oxyethylene units and having three or more carbon atoms (preferably May be a copolymer having 3 to 4) oxyethylene units.

  The weight average molecular weight of the polyalkylene polyol (a2) is preferably 1,000 or more, more preferably 2,000 or more, preferably 20,000 or less, more preferably 10,000 or less, further preferably 5, or less. It is less than 000.

  The content of the polyalkylene polyol (a2) is preferably 2% by mass or more, more preferably 10% by mass or more, preferably 50% by mass or less, more preferably 45% by mass or less in the polyol (A). It is.

  The polyol (A) may contain another polyol (a3) other than the polycarbonate polyol (a1) and the polyalkylene polyol (a2). Examples of the other polyol (a3) include polycarbonate polyols other than the polycarbonate polyol (a1), polyether polyols other than the polyalkylene polyol (a2), and polyester polyols.

  As polycarbonate polyols other than the said polycarbonate polyol (a1), the polycarbonate polyol compound etc. which have a unit derived from the said other hydroxy compound, and do not have a unit derived from the said hydroxy compound (d1) are mentioned, for example.

  As polyether polyols other than the said polyalkylene polyol (a2), 1 type, or 2 or more types can be used, For example, 1 type or 2 or more types of a compound which has 2 or more of active hydrogen atoms are used as an initiator. The compound etc. which carried out addition polymerization of the alkylene oxide are mentioned. Examples of the compound having two or more active hydrogen atoms include propylene glycol, trimethylene glycol, 1,3-butanediol, 1,4-butanediol, 1,6-hexanediol, neopentyl glycol, glycerin and di- Glycerin, trimethylolethane, trimethylolpropane, water, hexanetriol and the like can be mentioned. Moreover, as said alkylene oxide, a propylene oxide, a butylene oxide, a styrene oxide, epichlorohydrin, tetrahydrofuran etc. are mentioned, for example.

  As said polyester polyol, 1 type (s) or 2 or more types can be used, For example, the reaction product of polycarboxylic acid and a polyol, polylactone polyol, etc. can be used.

As the polycarboxylic acid, one or more kinds can be used. For example, aromatic polys such as orthophthalic acid, isophthalic acid, terephthalic acid, trimellitic acid, pyromellitic acid, biphenyl dicarboxylic acid, naphthalene dicarboxylic acid and the like Carboxylic acid; ethylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,8 Straight-chain aliphatic polyols such as 9-nonanediol, 1,10-decanediol, 1,12-dodecanediol, diethylene glycol, triethylene glycol, triethylene glycol, tetraethylene glycol; neopentyl glycol, 1,3-butanediol , 2,2-diethyl-1,3- Lopane diol, 2,2-diethylpropanediol, 3-methyl-1,5-pentanediol, 2-ethyl-2-butyl-1,3-propanediol, 2-methyl-1,8-octanediol, 2,4 -Branched-chain aliphatic polyols such as diethyl-1,5-pentanediol, trimethylolethane, trimethylolpropane and pentaerythritol; alicyclic polyols such as cyclopentanediol, cyclohexanediol and cyclohexanedimethanol; hydrogenated bisphenol A, An alkylene oxide adduct of hydrogenated bisphenol F; a polymer obtained by ring-opening polymerization of a lactone compound such as γ-butyrolactone and ε-butyrolactone to the above linear aliphatic or alicyclic polyol, and the like can be mentioned. Among them, aromatic polycarboxylic acids such as orthophthalic acid and terephthalic acid; and aliphatic polycarboxylic acids such as adipic acid, sebacic acid, decanedioic acid and dodecanedioic acid are more preferable.
As said polycarboxylic acid, you may use acid derivatives, such as lower alkyl ester derivatives, such as a methyl ester, an acid anhydride, and an acid halide, for example.

  As the polyol, ethylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, Linear aliphatic polyols such as 1,9-nonanediol, 1,10-decanediol, 1,12-dodecanediol, diethylene glycol, triethylene glycol, triethylene glycol and tetraethylene glycol; neopentyl glycol, 1,3- Butanediol, 2,2-diethyl-1,3-propanediol, 2,2-diethylpropanediol, 3-methyl-1,5-pentanediol, 2-ethyl-2-butyl-1,3-propanediol, 2-Methyl-1,8-octanediol, 2,4-diethyl- , 5-pentanediol, trimethylol ethane, trimethylol propane, etc. branched chain aliphatic polyols such as pentaerythritol and the like. Examples of the alicyclic polyol include alicyclic polyols such as cyclopentanediol, cyclohexanediol, cyclohexanedimethanol, hydrogenated bisphenol A, alkylene oxide adduct of hydrogenated bisphenol F, ethylene glycol in the aromatic polycarboxylic acid, Compounds obtained by adding alkylene glycol such as propylene glycol, tetramethylene glycol, neopentyl glycol, etc .; aromatic polyols such as bisphenol A, bisphenol F, benzenediol; aromatics such as 1,4-bis (β-hydroxyethoxy) benzene The compound etc. which made the alkylene glycol be added to the polyol are mentioned. Among them, aliphatic polyols such as ethylene glycol, 1,6-hexanediol, neopentyl glycol and the like are preferable.

  The equivalent ratio of the hydroxyl group of the polyol to the carboxyl group of the polycarboxylic acid (ie, [OH / COOH equivalent ratio)] is preferably 1.02 or more, more preferably 1.05 or more on a molar basis. Preferably it is 1.50 or less, More preferably, it is 1.30 or less If the said [OH / COOH equivalent ratio] is the said range, the polyol of a hydroxyl end can be produced more.

  The number average molecular weight of the polyester polyol is preferably 500 or more, more preferably 1,000 or more, still more preferably 2,000 or more, preferably 10 or more, from the viewpoint of improving the balance of physical properties such as strength and elongation. It is 000 or less, more preferably 8,000 or less, further preferably 6,000 or less.

  Examples of the polycaprolactone polyol include polylactone polyols obtained by ring-opening polymerization of lactone monomers such as α-acetolactone, β-propiolactone, γ-butyrolactone, ε-caprolactone, δ-valerolactone and the like. .

  The said polyisocyanate (B) is a compound which has 2 or more of isocyanate groups, 1 type, or 2 or more types can be used, For example, aliphatic polyisocyanate, alicyclic polyisocyanate, aromatic polyisocyanate is mentioned. Be

  Examples of the aliphatic polyisocyanate include hexamethylene diisocyanate (HDI), dimer acid diisocyanate, norbornene diisocyanate, lysine diisocyanate, tetramethyl xylylene diisocyanate and the like.

  Examples of the alicyclic polyisocyanate include isophorone diisocyanate (IPDI), hydrogenated diphenylmethane diisocyanate (hydrogenated MDI), hydrogenated xylylene diisocyanate (hydrogenated XDI), cyclohexane diisocyanate, dicyclohexylmethane diisocyanate, isophorone diisocyanate and the like. Be

  As the aromatic polyisocyanate, one or more kinds can be used, and, for example, phenylene diisocyanate, tolylene diisocyanate (TDI; its 2, 4 or 2 or 6 or their mixture), diphenylmethane diisocyanate ( MDI; its 4,4 ', 2,4' or 2,2 'or a mixture thereof, crude MDI), 1,5-naphthalene diisocyanate (NDI), xylylene diisocyanate (XDI), tetramethylxylene Aromatic diisocyanates such as diisocyanates; Polyphenylenepolymethylene polyisocyanates, formalin condensates of methylene diphenyl diisocyanates, and aromatic polymers having three or more isocyanate groups such as carbodiimide-modified diphenylmethane diisocyanates Such as isocyanate, and the like.

  The equivalent ratio ([NCO / OH equivalent ratio)] of the isocyanate group of the polyisocyanate (B) to the hydroxyl group of the polyol (A) is the melting temperature and workability of the moisture-curable adhesive, film properties and speed From the viewpoint of curability and the like, the molar ratio is preferably 1.1 or more, more preferably 1.2 or more, and preferably 4 or less, more preferably 3 or less.

  The isocyanate group content of the urethane prepolymer having an isocyanate group is preferably 1% by mass or more, more preferably 1.5% by mass or more, preferably 8% by mass or less, more preferably 7% by mass or less, and further Preferably it is 6 mass% or less.

  By reacting the polyol (A) with the polyisocyanate (B), a urethane prepolymer having an isocyanate group contained in the moisture-curable adhesive of the present invention can be produced. The reaction temperature is preferably 80 ° C. or more and 130 ° C. or less, and the reaction time is preferably 1 hour or more and 10 hours or less. The reaction atmosphere may be a dry air atmosphere or a closed atmosphere as long as it does not mix with water, and an inert gas atmosphere such as nitrogen and argon is preferable in the case of the reaction described above; In the case, it is preferable to remove the solvent during or after the reaction.

  A catalyst may be coexistent in the reaction. Examples of the catalyst include transition metal compound catalysts such as titanium tetrabutoxide, dibutyltin oxide, dibutyltin dilaurate, tin 2-ethyl caproate, zinc naphthenate, cobalt naphthenate, zinc 2-ethyl capronate, molybdenum glycolate And iron chloride, zinc chloride and the like, and an amine catalyst such as triethylamine, tributylamine, triethylenediamine, benzyl dibutylamine and the like.

  The moisture-curable adhesive of the present invention includes, in addition to the urethane prepolymer having an isocyanate group, a crystal nucleating agent, a foam stabilizer, an antioxidant, a defoamer, an ultraviolet absorber, an abrasive, a filler, a pigment, and a dye. Colorants, thickeners, surfactants, flame retardants, plasticizers, lubricants, antistatic agents, heat stabilizers, tackifiers, curing catalysts, stabilizers, fluorescent brighteners, silane coupling agents, waxes, etc. And a blending resin such as a thermoplastic resin and a thermosetting resin.

  The melt viscosity of the moisture-curable adhesive of the present invention is preferably 500 mPa · s or more, more preferably 1,000 mPa · s or more, preferably 50,000 mPa · s or less, more preferably at a measurement temperature of 120 ° C. It is 30,000 mPa · s or less. When the melt viscosity is in the above range, it is effective to improve the workability at the time of processing and prevent appearance defects such as air stagnation.

  The processing temperature of the moisture-curable adhesive of the present invention is at least the melting point of the resin composition, preferably 80 ° C. or more and 130 ° C. or less, more preferably 100 ° C. or more and 120 ° C. or less. When the processing temperature is in the above range, it is difficult to cause problems in operation, the operation efficiency is good, and deterioration, decomposition, gelation and the like of the resin composition can be suppressed.

  A laminate using the moisture-curable adhesive of the present invention is also included in the technical scope of the present invention.

  The thickness of the cured product layer of the moisture-curable adhesive of the present invention is preferably 10 μm or more and 5000 μm or less.

  As a method of obtaining an adhesive layer using the moisture curing type adhesive agent of this invention, the base material and a sheet | seat or a film are bonded together, for example, and the method of carrying out moisture curing is mentioned.

  As a method of bonding a base material and a sheet, a film or the like by using the moisture-curable adhesive of the present invention, for example, the moisture-curable adhesive is melted by heating to a range of 60 to 150 ° C. It coats on a substrate using a coater, a spray coater, a T-die coater, a knife coater etc., and pastes the said sheet etc. together to the application side, or it coats on the said sheet etc using a roll coater etc. A method may be used in which the base material is attached to the coated surface, and pressure bonding is appropriately performed according to the shape of the base material by a method such as a roll press, flat press, belt press or the like. After the pressure bonding, it may be aged for 1 to 7 days, if necessary.

  The moisture-curable adhesive of the present invention includes the electric and electronic parts manufacturing industry, the automobile manufacturing industry, the semiconductor parts manufacturing industry, the shoe manufacturing industry, the timber processing industry, the building materials industry, the bookbinding industry, the metal industry in addition to the building materials and fibers field. It can be used in a wide range of fields such as resin processing industry.

  Hereinafter, the present invention will be more specifically described by way of examples.

Synthesis Example 1: Synthesis of Polycarbonate Polyol (1)
In a four-necked flask equipped with a thermometer, a stirrer, an inert gas inlet and a reflux condenser, 50 parts by mass of diethylene glycol, 50 parts by mass of triethylene glycol and 152 parts by mass of diphenyl carbonate are charged, and tetraisopropyl titanate is used as a polycarbonateation catalyst. 0.01 mass% was added, reacted at 200 ° C. for 5 hours, and then reacted under reduced pressure for 10 hours to obtain polycarbonate polyol (1). The hydroxyl value of this polycarbonate polyol (1) was 55 mg KOH / g.

Synthesis Example 2 Synthesis of Polycarbonate Polyol (2)
In a four-necked flask equipped with a thermometer, a stirrer, an inert gas inlet and a reflux condenser, 70 parts by mass of diethylene glycol, 30 parts by mass of polyethylene glycol ("PEG # 200" manufactured by NOF Corporation), and 153 parts by mass of diphenyl carbonate Were added, 0.01% by mass of tetraisopropyl titanate was added as a polycarbonate conversion catalyst, reacted at 200 ° C. for 5 hours, and then reacted under reduced pressure for 10 hours to obtain polycarbonate polyol (2). The hydroxyl value of this polycarbonate polyol (2) was 57 mg KOH / g.

Synthesis Example 3: Synthesis of Polycarbonate Polyol (3)
50 parts by mass of triethylene glycol, 50 parts by mass of 1,4-butanediol and 173 parts by mass of diphenyl carbonate are charged into a four-necked flask equipped with a thermometer, a stirrer, an inert gas inlet and a reflux condenser, and a polycarbonate conversion catalyst 0.01% by mass of tetraisopropyl titanate was added thereto, reacted at 200 ° C. for 5 hours, and then reacted under reduced pressure for 10 hours to obtain polycarbonate polyol (3). The hydroxyl value of this polycarbonate polyol (3) was 37 mg KOH / g.

Synthesis Example 4 Synthesis of Polycarbonate Polyol (4)
In a four-necked flask equipped with a thermometer, a stirrer, an inert gas inlet and a reflux condenser, 20 parts by mass of triethylene glycol, 80 parts by mass of 1,4-butanediol and 127 parts by mass of diethyl carbonate are charged Then, 0.01 mass% of tetraisopropyl titanate was added, reacted at 120 ° C. for 10 hours, then reacted at 190 ° C. for 2 hours, and then reacted under reduced pressure for 10 hours to obtain polycarbonate polyol (4). The hydroxyl value of this polycarbonate polyol (4) was 38 mg KOH / g.

Synthesis Example 5 Synthesis of Moisture-Curable Polyurethane Adhesive (X-1) In a reaction apparatus having a stirrer, a reflux tube, and a thermometer, 99 parts by mass of polycarbonate polyol (1) and PET-1 (manufactured by Mitsui Chemicals Polyurethanes Co., Ltd .: 1 part by mass of T-700) was added, and dehydration was performed until the water content became 0.05% by mass or less under reduced pressure conditions. Then, after cooling to a container temperature of 70 ° C., 28 parts by mass of 4,4′-diphenylmethane diisocyanate is added, the temperature is raised to 100 ° C., and the reaction is carried out for about 3 hours until the isocyanate group content becomes constant. A moisture-curable polyurethane adhesive (X-1) containing the urethane prepolymer of 4.1 was obtained.

Synthesis Example 6 Synthesis of Moisture-Curable Polyurethane Adhesive (X-2) In a reaction apparatus having a stirrer, a reflux tube, and a thermometer, 17 parts by mass of polycarbonate polyol (1) and PEG # 4000 (manufactured by NOF Corporation) 40 21 parts by mass, 21 parts by mass of PES-1 (manufactured by DIC: MX-2913), 21 parts by mass of PES-2 (manufactured by DIC: MX-2906), and 1 part by mass of PET-1 (manufactured by Mitsui Chemicals Polyurethanes, Inc .: T-700) In addition, dehydration was performed until the water content became 0.05 mass% or less under reduced pressure conditions. Then, after cooling to a container temperature of 70 ° C., 27 parts by mass of 4,4′-diphenylmethane diisocyanate is added, and the temperature is raised to 100 ° C. to react for about 3 hours until the isocyanate group content becomes constant, NCO% A moisture-curable polyurethane adhesive (X-2) containing a urethane prepolymer of 4.0 was obtained.

Synthesis Example 7 Synthesis of Moisture-Curable Polyurethane Adhesive (X-3) In a reaction apparatus having a stirrer, a reflux tube, and a thermometer, 28 parts by mass of polycarbonate polyol (1) and PEG # 4000 (manufactured by NOF Corporation) 28 21 parts by mass, 21 parts by mass of PES-1 (manufactured by DIC: MX-2913), 21 parts by mass of PES-2 (manufactured by DIC: MX-2906), and 1 part by mass of PET-1 (manufactured by Mitsui Chemicals Polyurethanes, Inc .: T-700) In addition, dehydration was performed until the water content became 0.05 mass% or less under reduced pressure conditions. Then, after cooling to a container temperature of 70 ° C., 28 parts by mass of 4,4′-diphenylmethane diisocyanate is added, the temperature is raised to 100 ° C., and the reaction is carried out for about 3 hours until the isocyanate group content becomes constant. A moisture-curable polyurethane adhesive (X-3) containing a urethane prepolymer of 4.0 was obtained.

Synthesis Example 8 Synthesis of Moisture-Curable Polyurethane Adhesive (X-4) In a reaction apparatus having a stirrer, a reflux tube, and a thermometer, 28 parts by mass of polycarbonate polyol (2) and PEG # 4000 (manufactured by NOF Corp.) 28 21 parts by mass, 21 parts by mass of PES-1 (manufactured by DIC: MX-2913), 21 parts by mass of PES-2 (manufactured by DIC: MX-2906), and 1 part by mass of PET-1 (manufactured by Mitsui Chemicals Polyurethanes, Inc .: T-700) In addition, dehydration was performed until the water content became 0.05 mass% or less under reduced pressure conditions. Then, after cooling to a container temperature of 70 ° C., 28 parts by mass of 4,4′-diphenylmethane diisocyanate is added, the temperature is raised to 100 ° C., and the reaction is carried out for about 3 hours until the isocyanate group content becomes constant. A moisture-curable polyurethane adhesive (X-4) containing a urethane prepolymer of 3.9 was obtained.

Synthesis Example 9 Synthesis of Moisture-Curable Polyurethane Adhesive (X-5) In a reaction apparatus having a stirrer, a reflux pipe, and a thermometer, 28 parts by mass of polycarbonate polyol (3) and PEG # 4000 (manufactured by NOF Corporation) 28 21 parts by mass, 21 parts by mass of PES-1 (manufactured by DIC: MX-2913), 21 parts by mass of PES-2 (manufactured by DIC: MX-2906), and 1 part by mass of PET-1 (manufactured by Mitsui Chemicals Polyurethanes, Inc .: T-700) In addition, dehydration was performed until the water content became 0.05 mass% or less under reduced pressure conditions. Then, after cooling to a container temperature of 70 ° C., 27 parts by mass of 4,4′-diphenylmethane diisocyanate is added, and the temperature is raised to 100 ° C. to react for about 3 hours until the isocyanate group content becomes constant, NCO% A moisture-curable polyurethane adhesive (X-5) containing the urethane prepolymer of 4.1 was obtained.

Synthesis Example 10 Synthesis of Moisture-Curable Polyurethane Adhesive (X-6) In a reaction apparatus having a stirrer, a reflux tube, and a thermometer, 28 parts by mass of polycarbonate polyol (4) and PEG # 4000 (manufactured by NOF Corporation) 28 21 parts by mass, 21 parts by mass of PES-1 (manufactured by DIC: MX-2913), 21 parts by mass of PES-2 (manufactured by DIC: MX-2906), and 1 part by mass of PET-1 (manufactured by Mitsui Chemicals Polyurethanes, Inc .: T-700) In addition, dehydration was performed until the water content became 0.05 mass% or less under reduced pressure conditions. Then, after cooling to a container temperature of 70 ° C., 27 parts by mass of 4,4′-diphenylmethane diisocyanate is added, and the temperature is raised to 100 ° C. to react for about 3 hours until the isocyanate group content becomes constant, NCO% A moisture-curable polyurethane adhesive (X-6) containing the urethane prepolymer of 4.1 was obtained.

Synthesis Example 11 Synthesis of Moisture-Curable Polyurethane Adhesive (X′-1) In a reaction apparatus having a stirrer, a reflux tube, and a thermometer, 57 parts by mass of PEG # 4000 (manufactured by Nippon Oil & Fats Co., Ltd.) and PES-1 (DIC) Product: 21 parts by mass of MX-2913), 21 parts by mass of PES-2 (manufactured by DIC: MX-2906), and 1 part by mass of PET-1 (manufactured by Mitsui Chemicals Polyurethanes: T-700) It dehydrated until the rate became 0.05 mass% or less. Then, after cooling to a container temperature of 70 ° C., 27 parts by mass of 4,4′-diphenylmethane diisocyanate is added, and the temperature is raised to 100 ° C. to react for about 3 hours until the isocyanate group content becomes constant, NCO% A moisture-curable polyurethane adhesive (X'-1) containing a urethane prepolymer of 4.2 was obtained.

Synthesis Example 12 Synthesis of Moisture-Curable Polyurethane Adhesive (X′-2) In a reaction device having a stirrer, a reflux tube, and a thermometer, 21 parts by mass of PES-1 (manufactured by DIC: MX-2913) and PES- Add 78 parts by mass of 2 (DIC: MX-2906) and 1 part by mass of PET-1 (Mitsui Chemical Polyurethanes: T-700), and dehydrate under a reduced pressure condition until the water content becomes 0.05 mass% or less did. Next, 26 parts by mass of 4,4′-diphenylmethane diisocyanate is added after cooling to a container temperature of 70 ° C., and the temperature is raised to 100 ° C. to react for about 3 hours until the isocyanate group content becomes constant, NCO% A moisture-curable polyurethane adhesive (X'-2) containing a urethane prepolymer of 3.9 was obtained.

Example 1
The moisture-curable polyurethane adhesive (X-1) obtained in Synthesis Example 5 is heated and melted at 110 ° C., coated on a 100 μm thick PET (polyethylene terephthalate) film at a thickness of 80 μm, The same PET film was placed and bonded to obtain a laminate. In addition, a moisture curable polyurethane adhesive (X-1) is heated and melted at 110 ° C., and after applying a thickness of 80 μm on a release paper using a knife coater heated at 110 ° C., moisture curing treatment (temperature 23) The film was prepared by leaving the film for 3 days in a constant temperature and humidity chamber with a relative humidity of 65%.

[Examples 2 to 6, Comparative Examples 1 and 2]
A laminate and a film (Y-were prepared in the same manner as in Example 1 except that moisture-curable polyurethane adhesives (X-2) to (X-6), (X'-1) and (X'-2) were used. 2) to (Y-6), (Y'-1) and (Y'-2) were obtained.

[Method of evaluating adhesion strength]
After curing the laminates obtained in Examples and Comparative Examples for 10 days under conditions of 23 ° C. and 50% humidity, the laminate is exfoliated at a rate of 200 mm / min in the direction of 180 ° with respect to the width of 25 mm. The peel strength was measured and evaluated as follows.
剥離; Peeling strength is 15 N / 25 mm or more.
Good: Peeling strength is 10 N / 25 mm or more and less than 15 N / 25 mm.
X: Peeling strength is less than 10 N / 25 mm.

[Measuring method of moisture permeability]
Using the films obtained in Examples and Comparative Examples as test specimens, the moisture permeability is measured by the measurement method specified in JIS L-1099 A-1.
○; 1,000 g / m ² -24 h or more
△; 750g / m ^{2 -24h} or 1000g / m ^{2 -24h} less ×: 750 g / m less than ² -24H

  The moisture-curable adhesives of Examples 1 to 6 were the moisture-curable adhesives of the present invention, and were able to improve the adhesive strength while maintaining the humidity.

  On the other hand, the moisture-curable adhesive of Comparative Example 1 is formed using a polyol not containing a polycarbonate polyol (a1) having a unit derived from the hydroxy compound (d1) represented by the general formula (1) It was inferior in adhesive strength.

  The moisture-curable adhesive of Comparative Example 2 is formed using a polyol not containing a polycarbonate polyol (a1) having a unit derived from the hydroxy compound (d1) represented by the general formula (1). And was poor in moisture permeability.

Claims (5)

A moisture curable adhesive comprising a urethane prepolymer having an isocyanate group, the adhesive comprising:
The urethane prepolymer having an isocyanate group is a reactant of a polyol (A) and a polyisocyanate (B),
A moisture-curable adhesive, wherein the polyol (A) comprises a polycarbonate polyol (a1) having a unit derived from a hydroxy compound (d1) represented by the general formula (1).

[In general formula (1), n represents an integer of 2 or more and 7 or less. ]   The moisture curable adhesive according to claim 1, wherein the content of the polycarbonate polyol (a1) is 10% by mass or more in the polyol (A).   The moisture curable adhesive according to claim 1 or 2, wherein the number average molecular weight of the polycarbonate polyol (a1) is 500 or more and 8,000 or less.   The moisture curable adhesive according to any one of claims 1 to 3, wherein the content of the compound (d1) is 40% by mass or more in the hydroxy compound (D) which is a raw material of the polycarbonate polyol (a1). .   A laminate having a cured product layer of the moisture-curable adhesive according to any one of claims 1 to 4.