JP2015063579A - Moisture-curable polyurethane hot-melt resin composition, adhesive agent and laminate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a moisture-curable polyurethane hot-melt resin composition having high adhesiveness to various substrates including a polyamide and falling impact resistance.SOLUTION: There are provided: a moisture-curable polyurethane hot-melt resin composition comprising a polyurethane polymer having an isocyanate group obtained by reacting a polyol (A) containing a polyether polyol (A-1), a crystalline polyester polyol (A-2) and a polycarbonate polyol (A-3) with a xylylene diisocyanate (B); and an adhesive agent and a laminate using the same. The polyol (A) preferably further contains an amorphous polyester polyol (A-4).

Description

  The present invention relates to a moisture curable polyurethane hot melt resin composition, an adhesive using the same, and a laminate.

  Moisture-curing polyurethane urethane hot melt adhesives are solvent-free, so various researches have been made to date, focusing on fiber bonding and building material lamination, and are widely used in the industry as environmentally friendly adhesives. .

  In recent years, in response to the growing needs for lighter and thinner optical components, in the pasting of optical components, studies have been made to replace hot-melt adhesives with acrylic adhesives that have been the mainstream until now ( For example, see Patent Document 1.)

  However, as adherends (substrates) used for optical components, difficult-to-adhere substrates such as polyamide may be used, and a moisture-curable polyurethane hot melt adhesive is directly applied to these substrates. However, there was a problem that satisfactory adhesiveness could not be obtained.

Special table 2011-521040 gazette

  The problem to be solved by the present invention is to provide a moisture-curable polyurethane hot-melt resin composition that is excellent in adhesion to various substrates such as polyamide and in drop impact resistance.

  As the inventors of the present invention have been researching to solve the above-mentioned problems, the inventors have paid attention to polyols and polyisocyanates used as raw materials for urethane prepolymers, and have intensively studied to complete the present invention.

  That is, in the present invention, a polyol (A) containing a polyether polyol (A-1), a crystalline polyester polyol (A-2) and a polycarbonate polyol (A-3) is reacted with xylylene diisocyanate (B). The present invention provides a moisture-curable polyurethane hot-melt resin composition characterized by containing a urethane prepolymer having an isocyanate group, and an adhesive and a laminate obtained by using the moisture-curable polyurethane hot-melt resin composition.

The adhesive obtained using the moisture-curable polyurethane hot melt resin composition of the present invention,
Excellent adhesion to various base materials such as polyamide film, drop impact resistance, quick curing, flexibility, waterproofness, application workability (dischargeability) and shape retention, and open time (bondable time) Is also moderate.
Therefore, the adhesive obtained by using the moisture-curable polyurethane hot melt resin composition of the present invention can be suitably used not only for fiber bonding and building material lamination, but also for bonding optical members.

  The polyether polyol (A-1) is an essential component for imparting an appropriate melt viscosity and an appropriate open time after coating, and exhibiting excellent adhesiveness, waterproofness, flexibility and drop impact resistance. For example, polyethylene glycol, polypropylene glycol, polybutylene glycol, polytetramethylene glycol, ethylene oxide-modified polypropylene glycol and the like can be used. These polyether polyols may be used alone or in combination of two or more.

  As the number average molecular weight of the polyether polyol (A-1), the adhesiveness (particularly, the initial adhesive strength and the final adhesive strength) can be further improved, and the open time can be more easily adjusted. Is preferable, and it is more preferable that it is the range of 700-4,500. In addition, the number average molecular weight of the said polyether polyol (A-1) shows the value measured on condition of the following by gel permeation chromatography (GPC) method.

Measuring device: High-speed GPC device (“HLC-8220GPC” manufactured by Tosoh Corporation)
Column: The following columns manufactured by Tosoh Corporation were connected in series.
"TSKgel G5000" (7.8 mm ID x 30 cm) x 1 "TSKgel G4000" (7.8 mm ID x 30 cm) x 1 "TSKgel G3000" (7.8 mm ID x 30 cm) x 1 “TSKgel G2000” (7.8 mm ID × 30 cm) × 1 detector: RI (differential refractometer)
Column temperature: 40 ° C
Eluent: Tetrahydrofuran (THF)
Flow rate: 1.0 mL / min Injection amount: 100 μL (tetrahydrofuran solution with a sample concentration of 0.4 mass%)
Standard sample: A calibration curve was prepared using the following standard polystyrene.

(Standard polystyrene)
"TSKgel standard polystyrene A-500" manufactured by Tosoh Corporation
"TSKgel standard polystyrene A-1000" manufactured by Tosoh Corporation
"TSKgel standard polystyrene A-2500" manufactured by Tosoh Corporation
"TSKgel standard polystyrene A-5000" manufactured by Tosoh Corporation
"TSKgel standard polystyrene F-1" manufactured by Tosoh Corporation
"TSKgel standard polystyrene F-2" manufactured by Tosoh Corporation
"TSKgel standard polystyrene F-4" manufactured by Tosoh Corporation
"TSKgel standard polystyrene F-10" manufactured by Tosoh Corporation
"TSKgel standard polystyrene F-20" manufactured by Tosoh Corporation
"TSKgel standard polystyrene F-40" manufactured by Tosoh Corporation
"TSKgel standard polystyrene F-80" manufactured by Tosoh Corporation
"TSKgel standard polystyrene F-128" manufactured by Tosoh Corporation
"TSKgel standard polystyrene F-288" manufactured by Tosoh Corporation
"TSKgel standard polystyrene F-550" manufactured by Tosoh Corporation

  The glass transition temperature (Tmg) of the polyether polyol (A-1) is preferably in the range of −70 to 0 ° C. from the viewpoint of further improving the drop impact resistance, and is −50 to −10 ° C. More preferably, it is the range. In addition, the glass transition temperature of the said polyether polyol (A-1) shows the value measured by DSC based on JISK7121-1987, and specifically, the said (A -1) was added, the temperature was raised to (Tmg + 50 ° C.) at a rate of temperature increase of 10 ° C./minute, held for 3 minutes, then rapidly cooled, and the intermediate glass transition temperature (Tmg) read from the obtained differential heat curve Indicates.

  The crystalline polyester polyol (A-2) is an essential component for imparting excellent waterproofness, adhesiveness (particularly initial adhesive strength), open time and drop impact resistance, and has, for example, a hydroxyl group. A reaction product of a compound and a polybasic acid can be used. In the present invention, the crystallinity means that the peak of crystallization heat or heat of fusion can be confirmed in DSC (Differential Scanning Calorimetry) measurement based on JIS K 7121, and the non-crystalline property means the peak. Indicates an item that cannot be confirmed.

  Examples of the compound having a hydroxyl group include ethylene glycol, propylene glycol, butanediol, pentanediol, hexanediol, heptanediol, octanediol, nonanediol, decanediol, trimethylolpropane, trimethylolethane, and glycerin. Can do. These compounds may be used alone or in combination of two or more. Among these, it is preferable to use butanediol, hexanediol, octanediol, and decanediol from the viewpoint of improving crystallinity and further improving waterproofness and adhesiveness.

  Examples of the polybasic acid include oxalic acid, malonic acid, succinic acid, adipic acid, sebacic acid, azelaic acid, 1,12-dodecanedicarboxylic acid, and the like. These polybasic acids may be used alone or in combination of two or more.

  The number average molecular weight of the crystalline polyester polyol (A-2) is preferably in the range of 500 to 6,000, and in the range of 1,000 to 5,000, from the viewpoint of waterproofness and adhesiveness. It is more preferable. In addition, the number average molecular weight of the said crystalline polyester polyol (A-2) shows the value obtained by measuring similarly to the number average molecular weight of the said polyether polyol (A-1).

  The glass transition temperature of the crystalline polyester polyol (A-2) is preferably in the range of 40 to 130 ° C. from the viewpoint of further improving the adhesiveness (particularly the initial adhesive strength). In addition, the glass transition temperature of the said crystalline polyester polyol (A-2) shows the value obtained by measuring similarly to the said polyether polyol (A-1).

  The amount of the crystalline polyester polyol (A-2) used is 30 to 500 parts by mass with respect to 100 parts by mass of the polyether polyol (A-1) in terms of flexibility, adhesiveness and open time. The range is preferable, and the range of 50 to 400 parts by mass is more preferable.

  Moreover, as said crystalline polyester polyol (A-2), a polycaprolactone polyol can also be used. As said polycaprolactone polyol, what reacted the compound which has the above-mentioned hydroxyl group, and (epsilon) -caprolactone can be used, for example.

  When polycaprolactone polyol is used as (A-2), the number average molecular weight is preferably in the range of 20,000 to 200,000.

  The polycarbonate polyol (A-3) is an essential component for imparting excellent adhesion to polyamide, and is obtained, for example, by reacting a carbonate and / or phosgene with the above-mentioned compound having a hydroxyl group. Things can be used.

  As the carbonate ester, for example, methyl carbonate, dimethyl carbonate, ethyl carbonate, diethyl carbonate, cyclocarbonate, diphenyl carbonate and the like can be used. These compounds may be used alone or in combination of two or more.

  The number average molecular weight of the polycarbonate polyol (A-3) is preferably in the range of 500 to 5,000, more preferably in the range of 1,000 to 4,000, from the viewpoint of adhesiveness. In addition, the number average molecular weight of the said polycarbonate polyol (A-3) shows the value obtained by measuring similarly to the number average molecular weight of the said polyether polyol (A-1).

  As a glass transition temperature of the said polycarbonate polyol (A-3), it is preferable that it is the range of -30-20 degreeC from the point which can improve fall impact resistance and adhesiveness further. In addition, the glass transition temperature of the said polycarbonate polyol (A-3) shows the value obtained by measuring similarly to the said polyether polyol (A-1).

  The amount of the polycarbonate polyol (A-3) used is preferably in the range of 50 to 1,000 parts by mass with respect to 100 parts by mass of the polyether polyol (A-1) from the viewpoint of adhesiveness. The range of 100 to 800 parts by mass is more preferable.

  The polyol (A) contains the polyether polyol (A-1), the crystalline polyester polyol (A-2) and the polycarbonate polyol (A-3) as essential components. It is preferable to contain (A-4). By containing the amorphous polyester polyol (A-4), the thixotropy of the moisture-curable polyurethane hot melt resin composition of the present invention is reduced without impairing adhesiveness and drop impact resistance, which will be described later. Even when a discharge device having a small diameter such as a dispenser is used, excellent discharge properties can be obtained.

  As the amorphous polyester polyol (A-4), for example, a reaction product of a compound having a hydroxyl group and a polybasic acid can be used.

  Examples of the compound having a hydroxyl group include ethylene glycol, propylene glycol, 1,4-butanediol, pentanediol, 2,4-diethyl-1,5-pentanediol, 3-methyl-1,5-pentanediol, Hexanediol, neopentyl glycol, hexamethylene glycol, glycerin, trimethylolpropane, bisphenol A, bisphenol F, and alkylene oxide adducts thereof can be used. These compounds may be used alone or in combination of two or more. Among these, it is preferable to use an alkylene oxide adduct of bisphenol A from the viewpoint that adhesiveness (particularly, initial adhesive strength) and dischargeability can be further improved. The number of moles of the alkylene oxide added is preferably in the range of 2 to 10 moles, more preferably in the range of 4 to 8 moles.

  Examples of the polybasic acid include adipic acid, glutaric acid, pimelic acid, suberic acid, dimer acid, sebacic acid, undecanedicarboxylic acid, hexahydroterephthalic acid, phthalic acid, phthalic anhydride, isophthalic acid, terephthalic acid and the like. Can be used. These polybasic acids may be used alone or in combination of two or more. Among these, it is preferable to use sebacic acid and isophthalic acid from the viewpoint that adhesiveness (particularly, initial adhesive strength) and dischargeability can be further improved.

  The number average molecular weight of the amorphous polyester polyol (A-4) is preferably in the range of 500 to 5,000 from the viewpoint of further improving adhesiveness (particularly, initial adhesive strength) and dischargeability. The range of 1,000 to 4,000 is more preferable, and the range of 1,000 to 3,000 is more preferable.

  The glass transition temperature of the amorphous polyester polyol (A-4) is in the range of −50 to −10 ° C. from the viewpoint of further improving adhesiveness (particularly, initial adhesive strength) and dischargeability. preferable. In addition, the glass transition temperature of the said amorphous polyester polyol (A-4) shows the value measured similarly to the glass transition temperature of the said polyether polyol (A-1).

  As the usage-amount of the said amorphous polyester polyol (A-4), it is 10 with respect to 100 mass parts of said polyether polyol (A-1) from the point of adhesiveness (especially initial stage adhesive strength) and discharge property. It is preferable that it is the range of -500 mass parts, and the range of 50-300 mass parts is more preferable.

  The polyol (A) may contain other polyols such as polyacryl polyol, polybutadiene polyol, and dimer diol, if necessary.

  The xylylene diisocyanate (B) is an essential component particularly for imparting adhesion to polyamide and drop impact resistance, such as o-xylylene diisocyanate, m-xylylene diisocyanate, p-xylylene diisocyanate. Can be used. These xylylene diisocyanates may be used alone or in combination of two or more. Among these, m-xylylene diisocyanate is preferably used from the viewpoint of easy availability of raw materials.

  When obtaining the said urethane prepolymer, you may use together other polyisocyanate with the said xylylene diisocyanate (B) as needed.

  Examples of the other polyisocyanates include polymethylene polyphenyl polyisocyanate, diphenylmethane diisocyanate, carbodiimide-modified diphenylmethane diisocyanate isocyanate, phenylene diisocyanate, tolylene diisocyanate, and naphthalene diisocyanate; hexamethylene diisocyanate, lysine diisocyanate, cyclohexane Aliphatic or alicyclic polyisocyanates such as diisocyanate, isophorone diisocyanate, dicyclohexylmethane diisocyanate, and hydrogenated xylylene diisocyanate can be used. These polyisocyanates may be used alone or in combination of two or more. Among these, diphenylmethane diisocyanate is preferable from the viewpoint of reactivity and adhesiveness.

  The urethane prepolymer is obtained by reacting the polyol (A) with the xylylene diisocyanate (B), and reacts with moisture present in the air or in the base material to which the urethane prepolymer is applied. It has an isocyanate group that forms a crosslinked structure. Adhesiveness is manifested by moisture curing of the isocyanate group.

  As a method for producing the urethane prepolymer, for example, an isocyanate contained in the xylylene diisocyanate (B) is heated after dropping the mixture of the polyol (A) into a reaction vessel containing the xylylene diisocyanate (B). The method of manufacturing by making it react on conditions that group becomes excess with respect to the hydroxyl group which the said polyol (A) has is mentioned.

  When producing the urethane prepolymer, the equivalent ratio ([isocyanate group / hydroxyl group]) of the isocyanate group of the xylylene diisocyanate (B) and the hydroxyl group of the polyol (A) is 1.1-5. A range is preferable from the viewpoint of adhesiveness and drop impact resistance, and a range of 1.5 to 3 is more preferable.

  The isocyanate group content (hereinafter abbreviated as “NCO%”) of the urethane prepolymer obtained by the above method is in the range of 1.5 to 8% from the viewpoint of further improving the adhesiveness. Preferably, the range of 1.7-5 is more preferable, and the range of 1.8-3 is still more preferable. In addition, NCO% of the said urethane prepolymer shows the value measured by the potentiometric titration method based on JISK1603-1.

  As the viscosity of the urethane prepolymer, the melt viscosity at 125 ° C. is preferably in the range of 1,000 to 50,000 mPa · s, more preferably in the range of 2,000 to 10,000 mPa · s. The range of 4,200 to 7,000 mPa · s is more preferable. The melt viscosity at 125 ° C. of the urethane prepolymer indicates a value measured with a cone plate viscometer (manufactured by ICI).

  The moisture-curable polyurethane hot melt resin composition of the present invention contains the urethane prepolymer as an essential component, but may contain other additives as necessary.

  Examples of the other additives include a curing catalyst, a light stabilizer, an antioxidant, a tackifier, a plasticizer, a stabilizer, a filler, a dye, a pigment, and a silane coupling agent. These additives may be used alone or in combination of two or more. Among these, it is preferable to use a curing catalyst from the viewpoint that the rapid curability can be further improved.

  Examples of the curing catalyst include compounds having a nitrogen atom such as triethylamine, triethylenediamine, N-methylmorpholine; metal salts such as potassium acetate, zinc stearate, tin octylate; dibutyltin dilaurate, stannous octoate, dibutyl Organometallic compounds such as tin diacetate, dibutyltin marker butide, dibutyltin thiocarboxylate, dibutyltin dimaleate, dioctyltin markerbutide and dioctyltin thiocarboxylate; compounds represented by the following general formula (1) can be used. These curing catalysts may be used alone or in combination of two or more. Among these, it is preferable to use a compound represented by the following general formula (1) from the viewpoint that the fast curability can be further improved without impairing the adhesiveness and the drop impact resistance.

（式中、Ｒ^１及びＲ^２はそれぞれ独立に水素原子又はアルキル基を表し、ｎはそれぞれ独立に１〜６の整数を表す。）

(In the formula, R ¹ and R ² each independently represent a hydrogen atom or an alkyl group, and n independently represents an integer of 1 to 6)

  Among the compounds represented by the general formula (1), the curing catalyst includes 2,2′-dimorpholinodiethyl ether and di (2,6-dimethylmorpholinoethyl) from the viewpoint that the rapid curability can be further improved. It is preferable to use ether.

  As the usage-amount of the said curing catalyst, it is preferable that it is the range of 0.001-5 mass parts with respect to 100 mass parts of said urethane prepolymers from the point of quick-curing property, and 0.05-2 mass parts. A range is more preferred.

  The adhesive obtained by using the moisture-curable polyurethane hot melt resin composition of the present invention has adhesiveness to various base materials including polyamide, drop impact resistance, waterproofness, flexibility, fast curability, It is excellent in coating workability (dischargeability), shape retention after coating, and open time, and can be suitably used not only for fiber bonding and building material lamination but also for bonding optical members.

  As an aspect used for bonding of the said optical member, sealing agents, such as a mobile phone, a personal computer, a game machine, television, a car navigation system, a camera speaker, are mentioned, for example.

  In the case of performing the bonding, for example, the moisture-curable polyurethane hot melt resin composition is heated and melted in the range of 50 to 130 ° C., the composition is applied onto a substrate, and then the composition is heated. A laminate can be obtained by pasting the other substrate on top.

  Examples of the substrate include glass, polyamide resin, acrylic resin, urethane resin, silicon resin, epoxy resin, fluorine resin, polystyrene resin, polyester resin, polysulfone resin, polyarylate resin, polyvinyl chloride resin, polyvinylidene chloride, Norbornene resin, polyolefin resin, polyimide resin, alicyclic polyimide resin, cellulose resin, PC (polycarbonate), PBT (polybutylene terephthalate), modified PPE (polyphenylene ether), PEN (polyethylene naphthalate), PET (polyethylene terephthalate) , Lactic acid polymer, ABS resin, AS resin and the like can be used. Further, the substrate may be subjected to corona treatment, plasma treatment, primer treatment or the like, if necessary.

  Examples of the method for applying the moisture-curable polyurethane hot melt resin composition to the substrate include a method using a roll coater, spray coater, T-tie coater, knife coater, comma coater, etc .; dispenser, inkjet printing, screen Examples of the method include coating by a method such as printing and offset printing. In particular, the latter application method is preferable because the moisture-curable polyurethane hot melt resin composition can be precisely applied in a small amount on the base material to be applied, so that a loss such as punching does not occur. . Further, according to this coating method, the moisture curable polyurethane hot melt resin composition is continuously formed on the base material in various shapes such as dotted, linear, triangular, square, round, and curved. Or it can form intermittently.

  The thickness of the adhesive layer using the moisture-curable polyurethane hot melt resin composition can be set according to the intended use, but can be preferably set in the range of approximately 10 μm to 5 mm.

  The aging conditions after the bonding can be appropriately determined within a range of a temperature of 20 to 80 ° C., a relative humidity of 50 to 90%, and 0.5 to 5 days.

  Hereinafter, the present invention will be described in more detail with reference to examples.

[Example 1]
To a four-necked flask equipped with a thermometer, stirrer, inert gas inlet and reflux condenser, polycarbonate polyol ("Duranol T4672" manufactured by Asahi Kasei Chemicals Corporation, number average molecular weight; 2,000, Tmg; 10 ° C, Hereinafter, abbreviated as “T4672”.) 60 parts by mass, polytetramethine glycol (number average molecular weight; 2,000, Tmg; −50 ° C., hereinafter abbreviated as “PTMG2000”), 10 parts by mass, crystalline PEs-1 (Reaction of 1,6-hexanediol and sebacic acid, Tmg; 65 ° C., number average molecular weight; 3,500) 15 parts by mass were charged, and the water content was 0.05 mass at 100 ° C. under reduced pressure. It dehydrated until it became less than%.
Next, after cooling to 70 ° C. in the container, 13.2 parts by mass of xylylene diisocyanate (hereinafter abbreviated as “XDI”) and 0.03 parts by mass of tin octylate were added, and the temperature was raised to 100 ° C. It was made to react for about 3 hours until NCO group content rate became fixed, and the urethane prepolymer which has an isocyanate group was obtained, and it was set as the moisture hardening type polyurethane hot-melt resin composition.

[Examples 2-7, Comparative Examples 1-4]
A moisture-curable polyurethane hot melt resin composition was obtained in the same manner as in Example 1 except that the type and / or amount of polyol and the type and / or amount of polyisocyanate were changed as shown in Tables 1 and 2.

[Example 8]
A four-necked flask equipped with a thermometer, a stirrer, an inert gas inlet and a reflux condenser was charged with 30 parts by mass of T4672, 10 parts by mass of PTMG2000, and 27 parts by mass of crystalline PEs-1, and was amorphous. 20 parts by mass of reactive PEs-1 (a reaction product of 6 mol adduct of bisphenol A alkylene oxide, isophthalic acid and sebacic acid, Tmg; 10 ° C, number average molecular weight; 2,000) was charged at 100 ° C under reduced pressure. Dehydration was performed until the water content was 0.05% by mass or less under the conditions.
Next, after cooling to 70 ° C in the container, 13 parts by mass of XDI and 0.03 part by mass of tin octylate were added, the temperature was raised to 100 ° C, and the reaction was continued for about 3 hours until the NCO group content became constant. Thus, a urethane prepolymer having an isocyanate group was obtained. Next, 0.15 parts by mass of 2,2′-dimorpholinodiethyl ether was added to obtain a moisture-curable polyurethane hot melt resin composition.

[Adhesion evaluation method]
The moisture curable polyurethane hot melt resin compositions obtained in Examples and Comparative Examples were melted at 120 ° C. and applied on a 200 μm thick corona-treated PET with a roll coater at 100 μm, and a polyamide sheet (thickness 2 mm). ) And left in a thermostat bath at 23 ° C. and 65% RH for 3 days, respectively, and then the 180 ° C. peel strength (N / inch) was measured according to JIS K-7311.

[Drop impact resistance evaluation method]
Moisture curable polyurethane hot melt resin compositions obtained in Examples and Comparative Examples were melted at 120 ° C. and dispensed with a 0.6 mm inner diameter dispenser needle (“VALVE MASTER ME-5000VT”, Musashi Engineering, preheated to 120 ° C. Applied to a polyamide sheet (thickness 2 mm: 5 cm × 5 cm) at a discharge pressure of 0.3 MPa and a speed of 50 mm / sec. The plates were bonded and left for 3 days at 23 ° C. and 65% RH.
Next, with a DuPont drop impact tester, the presence or absence of peeling of the base material was visually observed under the condition that the impact was applied five times at a load of 300 g and a height of 30 cm through an impact core from an acrylic plate. Judgment was made as follows.
“T”: no peeling occurred.
“F”: Peeling occurred.

[Ejection evaluation method]
Moisture-curable polyurethane hot melt resin compositions obtained in Examples and Comparative Examples were melted to 120 ° C. and dispensed with a 0.6 mmΦ inner diameter dispenser needle (“VALVE MASTER ME-5000VT”, Musashi Engineering, preheated to 120 ° C. The discharge performance was determined as follows based on the coating amount (g) when discharged for 10 seconds at a discharge pressure of 0.3 MPa and a speed of 50 mm / second.
“A”; 0.4 g or more and less than 0.5 g “B”; 0.1 g or more and less than 0.4 g “C”; less than 0.1 g

Abbreviations in Tables 1 and 2 will be described.
"T5652": Polycarbonate polyol ("Duranol T5652" manufactured by Asahi Kasei Chemicals Corporation, Tmg; -10 ° C, number average molecular weight; 2,000)
"PPG2000"; polypropylene glycol, Tmg; -56 ° C, number average molecular weight; 2,000
"Crystalline PEs-2": 1,6-hexanediol and adipic acid reacted, number average molecular weight; 2,000, Tmg; 45 ° C

  It turned out that Examples 1-8 which are the moisture hardening type polyurethane hot-melt resin compositions of this invention have the outstanding adhesiveness with respect to polyamide, and drop impact resistance. Moreover, although Examples 4-8 are the aspects which further used the amorphous polyester polyol as a raw material of a urethane prepolymer, it turned out that it is excellent also in discharge property in addition to adhesiveness and drop impact resistance.

  On the other hand, although the comparative example 1 is an aspect which does not contain polyether polyol (A-1) as a raw material of a urethane prepolymer, the adhesiveness with respect to polyamide and the drop impact resistance were unsatisfactory.

  Although the comparative example 2 is an aspect which does not contain polycarbonate polyol (A-3) as a raw material of a urethane prepolymer, the adhesiveness with respect to polyamide was unsatisfactory.

  Comparative Examples 3 and 4 are embodiments in which diphenylmethane diisocyanate was used in place of xylylene diisocyanate (B) as a raw material for the urethane prepolymer, but the drop impact resistance was poor.

Claims (6)

An isocyanate group obtained by reacting a polyol (A) containing a polyether polyol (A-1), a crystalline polyester polyol (A-2) and a polycarbonate polyol (A-3) with xylylene diisocyanate (B). A moisture-curable polyurethane hot-melt resin composition comprising a urethane prepolymer. The moisture-curable polyurethane hot melt resin composition according to claim 1, wherein the polyol (A) further contains an amorphous polyester polyol (A-4). The moisture-curable polyurethane hot melt resin composition according to claim 2, wherein the amorphous polyester polyol (A-4) is obtained by reacting an alkylene oxide adduct of bisphenol A with a polybasic acid. An adhesive obtained by using the moisture-curable polyurethane hot melt resin composition according to any one of claims 1 to 3. A laminate comprising at least a base material (i) made of polyamide and an adhesive layer (ii) made of an adhesive according to claim 4. The laminate according to claim 5, which has an adhesive layer (ii) on a base material (i) made of polyamide.