Moisture-curing polyurethane hot-melt resin composition, adhesive, laminate, and method for bonding adherends.

Abstract

This disclosure provides a moisture-curing polyurethane hot-melt resin composition, etc., that can be applied in a fine line pattern and form a cured film with excellent adhesive strength and drop impact resistance. [Solution] A moisture-curing polyurethane hot-melt resin composition comprising a urethane prepolymer (i) having an isocyanate group, wherein the polyol (A) comprises at least a polyether polyol (a1) and a polyacrylic polyol (a2), and the polyamine (C) content is in the range of 0.1 parts by mass to 1.0 part by mass per 100 parts by mass of the urethane prepolymer (i).

Description

【Technical Field】 【0001】 The present invention relates to a moisture-curable polyurethane hot-melt resin composition. 【Background Art】 【0002】 A moisture-curable polyurethane hot-melt adhesive is an adhesive that exhibits the final adhesive strength through the moisture curing of isocyanate groups possessed by a urethane prepolymer as the main component. Since it is solvent-free, it is used as an environmentally friendly adhesive in various fields such as the construction field and the electronic device field. 【0003】 Among others, in electronic terminals such as smartphones and smartwatches, an adhesive used for joining components is required to have impact resistance against dropping so that components do not fall off when accidentally dropped during use. For example, Patent Document 1 discloses a moisture-curable polyurethane hot-melt adhesive excellent in impact resistance against dropping. 【Prior Art Documents】 【Patent Documents】 【0004】 【Patent Document 1】 Japanese Patent Application Laid-Open No. 2017-222776 【Summary of the Invention】 【Problems to be Solved by the Invention】 【0005】 With the miniaturization of electronic terminals and the enlargement of the device screens, the frame margins are becoming narrower and the bonding areas between components are becoming smaller. For example, an adhesive used for joining components such as a housing is required to be applied in a thin line using a dispenser. However, when the adhesive coating becomes thin, it becomes difficult to form a sufficient thickness of the adhesive, resulting in a problem that the adhesive strength and impact resistance decrease, and peeling or breakage of the adherent is likely to occur. 【0006】 The present disclosure provides a moisture-curing polyurethane hot-melt resin composition that can be applied in a fine line pattern and can form a cured film with excellent adhesive strength and drop impact resistance. [Means for solving the problem] 【0007】 In response to the above-mentioned problems, the inventors conducted diligent research and discovered that by using a moisture-curing polyurethane hot-melt resin composition with a predetermined composition, it is possible to form a narrow and thick coating film, which exhibits high adhesive strength and excellent drop impact resistance after curing. 【0008】 In other words, this disclosure includes the following embodiments. [1] A moisture-curing polyurethane hot-melt resin composition comprising a urethane prepolymer (i) having an isocyanate group, wherein the polyol (A) comprises at least a polyether polyol (a1) and a polyacrylic polyol (a2), and the polyamine (C) content is in the range of 0.1 parts by mass to 1.0 part by mass per 100 parts by mass of the urethane prepolymer (i). [2] The moisture-curing polyurethane hot melt resin composition described in [1] above, wherein the wetting spread index calculated by the method described below is 30 or less. (Wetting spread index) The moisture-curing polyurethane hot melt resin composition is heated and melted at 110°C for 30 minutes, and then applied in a straight line 25 mm long onto a polycarbonate (PC) plate (25 mm x 100 mm) using a dispenser needle with an inner diameter of 0.35 mm heated to 110°C at a processing speed of 50 mm / second. The line width after 5 seconds is W(5), and the line width after 180 seconds is W(180). The value is calculated using the following formula. Wetting spread index = ({W(180)-W(5)} / W(5))*100 [3] The moisture-curing polyurethane hot-melt resin composition according to [1] or [2] above, wherein the polyamine (C) is an aromatic polyamine. [4] The moisture-curing polyurethane hot melt resin composition according to any one of [1] to [3] above, wherein the polyether polyol (a1) contains a high molecular weight polyether polyol, and the content of the high molecular weight polyether polyol is in the range of 10 parts by mass to 50 parts by mass in 100 parts by mass of the raw material of the urethane prepolymer (i). [5] The moisture-curing polyurethane hot melt resin composition according to any one of [1] to [4] above, wherein the content of the polyacrylic polyol (a2) is in the range of 3 parts by mass to 20 parts by mass per 100 parts by mass of the raw material of the urethane prepolymer (i). [6] The moisture-curing polyurethane hot-melt resin composition according to any one of [1] to [5] above, wherein the polyol (A) further comprises at least one of polyester polyol (a3) ​​and polycarbonate polyol (a4). [7] The moisture-curing polyurethane hot-melt resin composition according to any one of [1] to [6] above, wherein the content of the polyisocyanate (B) is in the range of 10 parts by mass to 40 parts by mass in 100 parts by mass of the raw material of the urethane prepolymer (i). [8] An adhesive comprising the moisture-curing polyurethane hot-melt resin composition described in any of [1] to [7] above. [9] A laminate having at least a base material and a cured layer of a moisture-curing polyurethane hot-melt resin composition according to any of [1] to [7] above.

[10] A method for bonding adherends, comprising the steps of: melting a moisture-curing polyurethane hot melt resin composition according to any of [1] to [7] above, applying it to a first adherend using a dispenser to form a coating film; and bonding the first adherend and the second adherend via the coating film. [Effects of the Invention] 【0009】 The moisture-curing polyurethane hot-melt resin composition of this disclosure can be applied in a fine wire shape and can form a cured film with excellent adhesive strength and drop impact resistance. [Modes for carrying out the invention] 【0010】 I. Moisture-curing polyurethane hot-melt resin composition The moisture-curing polyurethane hot-melt resin composition of this disclosure (hereinafter sometimes abbreviated as "the resin composition of this disclosure") contains a urethane prepolymer (i) having isocyanate groups derived from a polyol (A), a polyisocyanate (B), and a polyamine (C), wherein the content of the polyamine (C) is in the range of 0.1 parts by mass to 1.0 part by mass per 100 parts by mass of the urethane prepolymer (i). 【0011】 According to the resin composition of this disclosure, by including a predetermined amount of polyamine in the urethane prepolymer (i), the cohesive force is improved while suppressing viscosity increase, enabling the formation of a narrow and thick cured film, and the cured film can exhibit flexibility and adhesive strength that can withstand impact from drops. 【0012】 The moisture-curing polyurethane hot-melt resin composition of this disclosure contains a urethane prepolymer (i) having isocyanate groups. The urethane prepolymer (i) having isocyanate groups is made from polyol (A), polyisocyanate (B), and polyamine (C) as raw materials (constituent materials). In other words, the urethane prepolymer (i) is a reaction product in which polyol (A), polyisocyanate (B), and polyamine (C) are essential reaction components. The raw materials (constituent materials) of the urethane prepolymer (i) and the reaction product may contain components other than polyol (A), polyisocyanate (B), and polyamine (C) to the extent that they do not impair the effects of the moisture-curing polyurethane hot-melt resin composition of this disclosure. 【0013】 <<Polyol (A)>> The polyol (A) described above preferably contains at least a polyether polyol (a1) and a polyacrylic polyol (a2) from the viewpoint that the cured product of the resin composition of this disclosure can exhibit and maintain good drop impact resistance and can demonstrate excellent adhesive strength in narrow widths. In particular, the polyol (A) preferably contains at least one of a polyester polyol (a3) ​​and a polycarbonate polyol (a4) in addition to the polyether polyol (a1) and polyacrylic polyol (a2), and the inclusion of a polyether polyol (a1) and a polyacrylic polyol (a2), as well as a polyester polyol (a3) ​​and a polycarbonate polyol (a4), is preferable from the viewpoint that it facilitates the formation of phase separation and is excellent in achieving both high drop impact resistance, high heat creep resistance, and high adhesion. 【0014】 <Polyether polyol (a1)> The above polyether polyol (a1) is a polyol having oxyalkylene units in its main chain. Examples of the above polyether polyol (a1) include polyethylene glycol, polypropylene glycol, polytetramethylene glycol, polyoxyethylene polyoxypropylene glycol, polyoxypropylene polyoxytetramethylene glycol, polyoxypropylene triol, etc. These may be used individually or in combination of two or more. Among these, from the viewpoint of improving the flexibility of the cured product of the resin composition of this disclosure and exhibiting excellent drop impact resistance, the above polyether polyol (a1) preferably contains one or more selected from the group consisting of polyethylene glycol, polypropylene glycol, and polyoxyethylene polyoxypropylene glycol. From the viewpoint of having better adhesive strength in addition to flexibility and drop impact resistance, it is preferable to contain at least polyoxyethylene polyoxypropylene glycol, and more preferably to contain polypropylene glycol and polyoxyethylene polyoxypropylene glycol. 【0015】 The above polyoxyethylene polyoxypropylene glycol is a polyether polyol having a polyoxyethylene group and a polyoxypropylene group. By using polyoxyethylene polyoxypropylene glycol as the polyether polyol (a1), the cured product (cured film) can be softened, and the impact resistance and adhesion can be enhanced. 【0016】 The above polyoxyethylene polyoxypropylene glycol can be produced, for example, by addition polymerization of an initiator composed of a compound having two or more active hydrogen atoms and an alkylene oxide such as ethylene oxide and propylene oxide. Specifically, it can be produced by batch mixing the above alkylene oxide or the like, or separately supplying and mixing them in the presence of the above initiator and reacting them. 【0017】 As the above initiator, for example, ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, trimethylolpropane, etc. can be used. In addition to ethylene oxide and propylene oxide, butylene oxide can be used in combination as needed as the above alkylene oxide. 【0018】 In the above polyoxyethylene polyoxypropylene glycol, the molar ratio [EO / PO] of the oxyethylene group (EO) to the oxypropylene group (PO) is preferably in the range of 5 / 95 to 90 / 10, and more preferably in the range of 5 / 95 to 50 / 50. 【0019】 The average functional group (hydroxyl group) number of the above polyoxyethylene polyoxypropylene glycol is preferably in the range of 1.5 to 3.0, and more preferably in the range of 1.5 to 2.5. 【0020】 The number average molecular weight of the polyether polyol (a1) is preferably in the range of 500 to 10,000, more preferably in the range of 750 to 9,000, and even more preferably in the range of 1,000 to 8,000. In particular, the polyether polyol (a1) preferably contains a polyether polyol with a number average molecular weight of 3,000 or more (hereinafter referred to as high molecular weight polyether polyol). By including a high molecular weight polyether polyol in the polyether polyol (a1), the drop impact resistance of the cured resin composition of this disclosure can be improved. The number average molecular weight of the high molecular weight polyether polyol is preferably in the range of 3,000 to 10,000, more preferably in the range of 3,500 to 9,000, and even more preferably in the range of 4,000 to 8,000. 【0021】 The number-average molecular weight of the above polyether polyol (a1) is shown as the value measured by gel permeation chromatography (GPC). The measurement conditions are those shown in the examples described later. 【0022】 The amount of the above-mentioned polyether polyol (a1) used is preferably in the range of 10 to 55 parts by mass, more preferably in the range of 15 to 50 parts by mass, and even more preferably in the range of 20 to 45 parts by mass, per 100 parts by mass of the raw materials constituting the urethane prepolymer (i). Among the above-mentioned polyether polyol (a1), it is preferably in the range of 10 to 50 parts by mass, more preferably in the range of 12 to 45 parts by mass, even more preferably in the range of 14 to 40 parts by mass, or in the range of 15 to 40 parts by mass, or 20 to 35 parts by mass, per 100 parts by mass of the raw materials constituting the urethane prepolymer (i). By setting the amount of high molecular weight polyether polyol in the raw materials constituting the urethane prepolymer (i) to the above range, the drop impact resistance of the resin composition of this disclosure can be further improved. 【0023】 The content of the polyether polyol (a1) in the polyol (A) is preferably in the range of 15% to 60% by mass, more preferably in the range of 20% to 55% by mass, and even more preferably in the range of 25% to 50% by mass, based on the total amount (100% by mass) of the polyol (A). 【0024】 Furthermore, the proportion of high molecular weight polyether polyol in the above polyether polyol (a1) is such that the amount of high molecular weight polyether polyol in the raw materials constituting the urethane prepolymer (i) is within the above range. Preferably, it is in the range of 40% to 100% by mass, more preferably in the range of 45% to 90% by mass, and even more preferably in the range of 50% to 80% by mass, out of 100% by mass of the total amount of the above polyether polyol (a1). By setting the amount of high molecular weight polyether polyol in the polyether polyol (a1) within the above range, it is possible to maintain adhesive strength while having excellent drop impact resistance. 【0025】 <Polyacrylic polyol (a2)> The above polyacrylic polyol (a2) can be, for example, a polymer of a (meth)acrylic compound that essentially contains a (meth)acrylic compound having a hydroxyl group. In this disclosure, "(meth)acrylic compound" refers to one or both of a methacrylic compound and an acrylic compound, and "(meth)acrylate" refers to one or both of a methacrylate and an acrylate. 【0026】 Examples of the above-mentioned (meth)acrylic compounds having a hydroxyl group include 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate (2-HBA), 3-hydroxypropyl (meth)acrylate (3-HPA), and 4-hydroxybutyl (meth)acrylate (4-HBA). These compounds may be used individually or in combination of two or more. Among the above-mentioned (meth)acrylic compounds having a hydroxyl group, 2-hydroxyethyl (meth)acrylate is preferred. 【0027】 Other (meth)acrylic compounds besides the above-mentioned (meth)acrylic compounds having a hydroxyl group include, for example, alkyl (meth)acrylates such as (meth)acrylic acid, methyl (meth)acrylate, ethyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, tert-butyl (meth)acrylate, neopentyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, octyl (meth)acrylate, stearyl (meth)acrylate, isostearyl (meth)acrylate, cetyl (meth)acrylate, lauryl (meth)acrylate, etc.; 2,2,2-trifluoroethyl (meth)acrylate, 2,2,3,3-tetrafluoropropyl (meth)acrylate, 1H,1H,5H-octafluoropentyl (meth)acrylate, 2- (Meth)acrylic compounds having a fluorine atom, such as (perfluorooctyl)ethyl (meth)acrylate; (meth)acrylic compounds having an alicyclic structure, such as isobornyl (meth)acrylate, cyclohexyl (meth)acrylate, sidiclopentanyl (meth)acrylate, and dicyclopentenyloxyethyl (meth)acrylate; (meth)acrylic compounds having an ether group, such as polyethylene glycol mono(meth)acrylate, methoxyethyl (meth)acrylate, methoxybutyl (meth)acrylate, methoxytriethylene glycol (meth)acrylate, and methoxypolyethylene glycol (meth)acrylate; benzyl (meth)acrylate, 2-ethyl-2-methyl-[1,3]-dioxolan-4-yl-methyl (meth)acrylate, and dimethylaminoethyl (meth)acrylate can be used. These compounds may be used individually or in combination of two or more. Among these, alkyl (meth)acrylate is preferred, and methyl (meth)acrylate and / or n-butyl (meth)acrylate are more preferred, as they provide even better adhesion and drop impact resistance. 【0028】 The number-average molecular weight of the above acrylic polyol (a2) is preferably in the range of 5,000 to 100,000, and more preferably in the range of 10,000 to 30,000, from the viewpoint of obtaining even better drop impact resistance and adhesive properties. The number-average molecular weight of the above acrylic polyol (a2) is shown as the value measured by gel permeation chromatography (GPC). The measurement conditions are those described in the examples below. 【0029】 The glass transition temperature of the above acrylic polyol (a2) is preferably in the range of 40°C to 120°C, and more preferably in the range of 50°C to 90°C, in order to obtain even better drop impact resistance and adhesion. The glass transition temperature of the above acrylic polyol (a2) is shown as the value measured by DSC in accordance with JIS K 7121-1987. Specifically, the above polyacrylic polyol (a2) is placed in a differential scanning calorimeter, heated to (Tg + 50°C) at a heating rate of 10°C / min, held for 3 minutes, then rapidly cooled, and the midpoint glass transition temperature (Tmg) read from the obtained differential thermal curve is shown. 【0030】 The amount of acrylic polyol (a2) used is preferably in the range of 3 to 20 parts by mass, more preferably in the range of 4 to 18 parts by mass, and even more preferably in the range of 5 to 15 parts by mass, based on 100 parts by mass of the raw materials constituting the urethane prepolymer (i), in order to obtain even better drop impact resistance and adhesion. The above amount may also be in the range of 5 to 20 parts by mass, 7 to 18 parts by mass, or 10 to 15 parts by mass. 【0031】 The content of the acrylic polyol (a2) in the polyol (A) is preferably in the range of 3% to 35% by mass, more preferably in the range of 4% to 30% by mass, and even more preferably in the range of 5% to 25% by mass, based on the total amount (100% by mass) of the polyol (A), in order to obtain even better drop impact resistance and adhesion. 【0032】 <Polyester polyol (a3)> The above polyol (a) preferably contains polyester polyol (a3) ​​in order to obtain excellent adhesion due to cohesive force. 【0033】 The above polyester polyol (a3) ​​may be crystalline or amorphous, and a combination of crystalline and amorphous polyester polyols may be used. In particular, the above polyester polyol (a3) ​​preferably contains a crystalline polyester polyol from the viewpoint of suppressing foaming during moisture curing. In this disclosure, "crystalline" refers to a material in which a peak of crystallization heat or fusion heat can be confirmed in a DSC (differential scanning calorimeter) measurement in accordance with JIS K 7121:2012, and "amorphous" refers to a material in which the above peak cannot be confirmed. 【0034】 The above polyester polyol (a3) ​​preferably includes a crystalline polyester polyol (hereinafter sometimes referred to as a highly crystalline polyester polyol) whose melting point on the 2nd run of a DSC (differential scanning calorimetry) is 53°C or higher. The highly crystalline polyester polyol preferably has a melting point on the 2nd run of a DSC (differential scanning calorimetry) of 53°C or higher, and more preferably in the range of 55°C to 100°C, and more preferably in the range of 60°C to 80°C. The melting point and crystallinity of the crystalline polyester polyol can be adjusted by selecting raw material monomers, copolymerization composition, average molecular weight, etc. 【0035】 The proportion of crystalline polyester polyol in the above polyester polyol (a3) ​​is preferably in the range of 30% to 100% by mass, more preferably in the range of 40% to 100% by mass, and even more preferably in the range of 50% to 100% by mass, based on 100% by mass of the above polyester polyol (a3). By setting the proportion of crystalline polyester polyol in the polyester polyol (a3) ​​within the above range, the cured product of the resin composition of this disclosure can exhibit good adhesive strength (normal strength). In particular, the proportion of highly crystalline polyester polyol in the above polyester polyol (a3) ​​is preferably in the range of 5% to 70% by mass, more preferably in the range of 7% to 60% by mass, and even more preferably in the range of 9% to 50% by mass, based on 100% by mass of the above polyester polyol (a3). By setting the proportion of highly crystalline polyester polyol in the above polyester polyol (a3) ​​within the above range, the adhesive strength of the cured product of the resin composition of this disclosure can be increased while maintaining heat creep resistance and drop impact resistance. The proportion of the highly crystalline polyester polyol may be in the range of 5% to 100% by mass, 10% to 80% by mass, or 15% to 60% by mass out of 100% by mass of polyester polyol (a3). 【0036】 The above polyester polyol (a3) ​​can be, for example, a reaction product (condensate) of a compound having a hydroxyl group and a polybasic acid; polycaprolactone polyol, etc. 【0037】 As the above-mentioned compounds having hydroxyl groups, compounds having two or more hydroxyl groups are preferred, and for example, ethylene glycol, propylene glycol, butanediol, pentanediol, hexanediol, heptanediol, octanediol, nonanediol, decanediol, trimethylolpropane, trimethylolethane, glycerin, etc. can be used. These compounds may be used individually or in combination of two or more. Among these, it is preferable to use one or more selected from the group consisting of butanediol, hexanediol, octanediol, and decanediol, in order to enhance crystallinity and obtain even better adhesion. 【0038】 Examples of the polybasic acids mentioned above include oxalic acid, malonic acid, succinic acid, adipic acid, sebacic acid, azelaic acid, and dodecanedioic acid. These compounds may be used individually or in combination of two or more. Among these, one or more selected from the group consisting of succinic acid, adipic acid, sebacic acid, and dodecanedioic acid are preferred because they enhance crystallinity and provide even better adhesion. 【0039】 As the caprolactone polyol mentioned above, for example, a reaction product of a compound having two or more hydroxyl groups and ε-caprolactone can be used. 【0040】 Among polyester polyols (a3), highly crystalline polyester polyols are not particularly limited as long as they are combinations of polyhydric alcohols and polybasic acids whose melting point in the 2nd run of a DSC (differential scanning calorimeter) falls within the range described above, but the following compounds can be given as examples. • A condensate of ethylene glycol and sebacic acid with a number-average molecular weight of 3000 or more. • A condensate of 1,3-propanediol with a number-average molecular weight of 3500 or more and sebacic acid. • A condensate of 1,4-butanediol with a number-average molecular weight of 3500 or more and sebacic acid. • A condensate of 1,6-hexanediol with a number-average molecular weight of 3000 or more and sebaciac acid. • A condensate of 1,6-hexanediol with a number-average molecular weight of 3000 or more and dodecanediic acid. • A condensate of 1,6-hexanediol with a number-average molecular weight of 4000 or more and adipic acid. • A condensate of 1,4-butanediol with a number-average molecular weight of 4000 or more and adipic acid. However, highly crystalline polyester polyols are not limited to these example compounds. 【0041】 The number-average molecular weight of the above polyester polyol (a3) ​​is preferably in the range of 500 to 10,000, and more preferably in the range of 1,000 to 6,000, from the standpoint of obtaining even better adhesion. In particular, the number-average molecular weight of highly crystalline polyester polyols is preferably in the range of 3,000 to 8,500, and more preferably in the range of 3,500 to 6,000. The number-average molecular weight of the above polyester polyol (a3) ​​is shown as the value measured by gel permeation chromatography (GPC). The measurement conditions are those described in the examples below. 【0042】 The amount of polyester polyol (a3) ​​used is 0% by mass or more in 100 parts by mass of the raw materials constituting the urethane prepolymer (i). In particular, the resin composition of this disclosure is preferably in the range of 5 to 50 parts by mass, and more preferably in the range of 10 to 40 parts by mass, in order to obtain even better adhesion. In particular, the amount of crystalline polyester polyol used, especially the amount of highly crystalline polyester polyol used, is preferably 15 parts by mass or less in 100 parts by mass of the raw materials constituting the urethane prepolymer (i), preferably in the range of 1.5 to 15 parts by mass, and more preferably in the range of 3 to 10 parts by mass. By setting the amount of highly crystalline polyester polyol used within the above range, the resin composition of this disclosure has good drop impact resistance and heat creep resistance, and foaming during moisture curing is sufficiently suppressed, thereby further increasing the adhesive strength. If the amount of highly crystalline polyester polyol used is too high, the drop impact resistance and heat creep resistance of the resin composition of this disclosure may decrease. 【0043】 The content of the polyester polyol (a3) ​​in the polyol (A) is 0% by mass or more of the total amount of polyol (A) (100% by mass), and in order to obtain even better adhesion, the range of 11% by mass to 55% by mass, more preferably 13% by mass to 50% by mass, and even more preferably 15% by mass to 45% by mass of the total amount of polyol (A) (100% by mass). 【0044】 <Polycarbonate polyol (a4)> The polyol (a) above preferably includes a polycarbonate polyol (a4) from the viewpoint of making the resin composition of this disclosure more likely to form phase separation and further improving thixotropy and heat creep resistance. The polycarbonate polyol (a4) above can be, for example, a reaction product of a compound having two or more hydroxyl groups with a carbonate ester and / or phosgene. 【0045】 Examples of compounds having two or more hydroxyl groups include propanediol, butanediol, pentanediol, hexanediol, decanediol, caprolactone, cyclohexanedimethanol, 3-methyl-1,5-pentanediol, neopentyl glycol, isosorbide, and the like. These compounds may be used individually or in combination of two or more. 【0046】 Examples of the above-mentioned carbonate esters include dimethyl carbonate, diethyl carbonate, diphenyl carbonate, ethylene carbonate, and propylene carbonate. These compounds may be used individually or in combination of two or more. 【0047】 The above polycarbonate polyol (a4) may be crystalline or amorphous, and a combination of crystalline and amorphous polycarbonate polyols may be used. In particular, from the viewpoint of suppressing foaming during moisture curing, it is preferable to include a crystalline polycarbonate polyol. 【0048】 Furthermore, the polycarbonate polyol (a4) may be liquid or solid at room temperature. In this disclosure, "liquid at room temperature" means that the polycarbonate polyol (a4) is liquid or viscous, exhibiting fluidity at 23°C. 【0049】 The number-average molecular weight of the above polycarbonate polyol (a4) is preferably in the range of 500 to 10,000, and more preferably in the range of 700 to 4,000, from the standpoint of obtaining even better adhesion. The number-average molecular weight of the above polycarbonate polyol (a4) is shown as the value measured by gel permeation chromatography (GPC). The measurement conditions are those described in the examples below. 【0050】 The amount of polycarbonate polyol (a4) used is 0% by mass or more per 100 parts by mass of the raw materials constituting the urethane prepolymer (i). In particular, from the standpoint of enhancing the thixotropy of the resin composition of this disclosure and obtaining even better heat creep resistance, the amount is preferably in the range of 3 to 30 parts by mass, more preferably in the range of 5 to 27 parts by mass, and even more preferably in the range of 7 to 24 parts by mass per 100 parts by mass of the raw materials constituting the urethane prepolymer (i). The amount of polycarbonate polyol (a4) used may also be in the range of 5 to 30 parts by mass, 10 to 27 parts by mass, or 15 to 24 parts by mass per 100 parts by mass of the raw materials constituting the urethane prepolymer (i). 【0051】 The content of the polycarbonate polyol (a4) in the polyol (A) is 0% by mass or more, and in particular, from the perspective of obtaining even better adhesion, it is preferably in the range of 0% to 35% by mass, more preferably in the range of 5% to 30% by mass, and even more preferably in the range of 10% to 25% by mass, based on the total amount of polyol (A) (100% by mass). 【0052】 <Other polyols> The polyol (A) described above may be used in combination with other polyols as needed. Examples of other polyols include polybutadiene polyol, dimer ol, etc. These polyols may be used individually or in combination of two or more. 【0053】 <Polyol (A)> The total content of polyether polyol (a1) and polyacrylic polyol (a2) in the total amount of polyol (A) can be in the range of 30% to 100% by mass, preferably in the range of 30% to 90% by mass, and more preferably in the range of 40% to 80% by mass, based on 100% by mass of the total amount of polyol (A). 【0054】 The total proportion of crystalline polyol in the total amount of polyol (A) is preferably in the range of 10 to 70 parts by mass, preferably in the range of 10 to 60 parts by mass, preferably in the range of 15 to 60 parts by mass, and preferably in the range of 15 to 50 parts by mass, per 100 parts by mass of the total amount of polyol (A). 【0055】 The amount of polyol (A) used (total content) in 100 parts by mass of the raw materials constituting the urethane prepolymer (i) is not particularly limited as long as the effects of the resin composition of this disclosure can be achieved. For example, the amount of polyol (A) can be 50 parts by mass or more in 100 parts by mass of the raw materials constituting the urethane prepolymer (i), preferably 60 parts by mass or more, more preferably 65 parts by mass or more, and even more preferably 70 parts by mass or more. Furthermore, the upper limit of the amount of polyol (A) used (total content) in the urethane prepolymer (i) is not particularly limited as long as the effects of the resin composition of this disclosure can be achieved. For example, it can be 90 parts by mass or less, preferably 85 parts by mass or less, and more preferably 80 parts by mass or less. 【0056】 <<Polyisocyanate (B)>> As the above polyisocyanate (B), for example, aromatic polyisocyanates such as polymethylene polyphenyl polyisocyanate, diphenylmethane diisocyanate, carbodiimide-modified diphenylmethane diisocyanate isocyanate, phenylene diisocyanate, tolylene diisocyanate, and naphthalene diisocyanate can be used; and aliphatic or alicyclic polyisocyanates such as hexamethylene diisocyanate, lysine diisocyanate, cyclohexane diisocyanate, isophorone diisocyanate, dicyclohexylmethane diisocyanate, xylylene diisocyanate, and tetramethylxylylene diisocyanate can be used. Among these, aromatic polyisocyanates are preferred, and diphenylmethane diisocyanate is more preferred, as they provide even better reactivity and adhesion. 【0057】 From the viewpoint of improving the drop impact resistance and heat creep resistance of the resin composition of this disclosure, the amount of polyisocyanate (B) used is preferably in the range of 10 to 40 parts by mass, more preferably in the range of 13 to 35 parts by mass, even more preferably in the range of 15 to 35 parts by mass, even more preferably in the range of 15 to 30 parts by mass, and even more preferably in the range of 20 to 30 parts by mass, per 100 parts by mass of the raw materials constituting the urethane prepolymer (i). If the amount of polyisocyanate (B) used is too high, drop impact resistance will be difficult to obtain, and if it is too low, heat creep resistance will be difficult to obtain. 【0058】 <<Polyamine (C)>> In the resin composition of this disclosure, the polyamine (C) content is in the range of 0.1 parts by mass to 1.0 parts by mass per 100 parts by mass of the urethane prepolymer (i), with a preferred range of 0.15 parts by mass to 0.7 parts by mass, and a more preferred range of 0.2 parts by mass to 0.5 parts by mass. 【0059】 The polyamine (C) described above is not particularly limited as long as it is a compound having two or more amino groups in its molecule, and for example, aliphatic polyamines, alicyclic polyamines, aromatic polyamines, etc., can be used. One type of polyamine may be used alone, or two or more types may be used in combination. 【0060】 Examples of the above-mentioned aliphatic polyamines include ethylenediamine, propylenediamine, butylenediamine, diethylenetriamine, triethylenetriamine, triethylenetetramine, tetraethylenepentamine, pentaethylenehexamine, hexamethylenediamine, trimethylhexamethylenediamine, 1,2-propanediamine, iminobispropylamine, methyliminobispropylamine, and 1,5-diamino-2-methylpentane (MPMD). These may be used individually or in combination of two or more. 【0061】 Examples of the above-mentioned alicyclic polyamines include isophorone diamine (IPDA), norbornane diamine, 1,2-cyclohexanediamine, 1,3-cyclohexanediamine, 1,4-cyclohexanediamine, 4,4'-methylenebis(cyclohexylamine), and piperazine. These may be used individually or in combination of two or more. 【0062】 The above aromatic polyamines include 1,4-diaminobenzene, 1,3-diaminobenzene, 1,2-diaminobenzene, 1,5-diaminonaphthalene, 1,8-diaminonaphthalene, 2,3-diaminonaphthalene, 2,6-diaminotoluene, 2,4-diaminotoluene, 3,4-diaminotoluene, 4,4'-diaminodiphenylmethane, 3,4'-diaminodiphenyl ether, 4,4'-diaminodiphenyl ether, 4,4'-diamino-1,2-diphenylethane, and 3,3'-diaminodiphenylmethane. Examples of aromatic diamines include 3,4'-diaminodiphenylmethane, 4,4'-diaminobenzophenone, 4,4'-diaminodiphenylsulfone, 3,3'-diaminobenzophenone, 3,3'-diaminodiphenylsulfone, bisanilinefluorene (BAF), 4,4'-methylenebis(2-ethyl-6-methylaniline), 4,4'-methylenebis(2-ethylaniline), 4,4'-methylenebis(2,6-diethylaniline), and 4,4'-methylenebis(2,6-diisopropylaniline). These may be used individually or in combination of two or more. 【0063】 In particular, the polyamine (C) mentioned above is preferably an aromatic diamine because it readily exhibits a wetting spread suppression effect even with a small amount of addition. 【0064】 The number-average molecular weight (Mn) of the polyamine (C) is preferably in the range of 100 to 1000, and more preferably in the range of 150 to 500. The number-average molecular weight of the polyamine (C) is shown as the value measured by gel permeation chromatography (GPC). The measurement conditions are those shown in the examples described later. 【0065】 <<Urethane prepolymer (i)>> The above urethane prepolymer (i) is obtained by reacting the above polyol (A), the above polyisocyanate (B), and the above polyamine (C). The above urethane prepolymer (i) has isocyanate groups at the polymer ends or within the molecule that can react with moisture present in the air or in the housing or adherend to which the urethane prepolymer is applied to form a crosslinked structure. 【0066】 The method for producing the above-mentioned urethane prepolymer (i) is not particularly limited, but for example, it can be produced by mixing the above-mentioned polyol (A) and the above-mentioned polyamine (C), dehydrating them by heating under reduced pressure, then adding the above-mentioned polyisocyanate (B) dropwise and heating, and reacting under conditions in which the isocyanate groups of the polyisocyanate (B) are in excess of the hydroxyl groups of the polyol (A). 【0067】 The equivalent ratio ([active hydrogen group] / [isocyanate group]) of the hydroxyl group of polyol (A) and the amino group of polyamine (C) (hereinafter, the above hydroxyl group and amino group are referred to as active hydrogen groups) and the isocyanate group of polyisocyanate (B) is preferably in the range of 0.25 to 0.70 in molar ratio, more preferably in the range of 0.30 to 0.65, and even more preferably in the range of 0.35 to 0.60. Furthermore, the equivalent ratio ([hydroxyl group] / [amino group]) of the hydroxyl group of polyol (A) and the amino group of polyamine (C) is preferably in the range of 22 to 140 in molar ratio, more preferably in the range of 25 to 120, and even more preferably in the range of 30 to 100. 【0068】 The isocyanate group content (hereinafter abbreviated as "NCO%") of the above urethane prepolymer (i) is preferably in the range of 1.5% to 7% by mass, and more preferably in the range of 1.8% to 5% by mass, from the viewpoint of obtaining even better drop impact resistance, heat creep resistance, and adhesion. The NCO% of the above urethane prepolymer (i) is the value measured by potentiometric titration in accordance with JIS K 1603-1:2007. 【0069】 The above urethane prepolymer (i) requires the above polyol (A), the above polyisocyanate (B), and the above polyamine (C) as essential raw materials, but may also contain any other raw materials as needed. In the raw materials (100% by mass) constituting the above-mentioned urethane prepolymer (i), the total content of the above-mentioned polyol (A), the above-mentioned polyisocyanate (B), and the above-mentioned polyamine (C) is preferably 90% by mass or more, more preferably 95% by mass or more, and particularly preferably 100% by mass. 【0070】 <<Moisture-curing polyurethane hot-melt resin composition>> The moisture-curing polyurethane hot-melt resin composition of this disclosure comprises the above-mentioned urethane prepolymer (i) as an essential component, but may also contain other additives as needed. Examples of these other additives include antioxidants, tackifiers, plasticizers, stabilizers, fillers, dyes, pigments, fluorescent whitening agents, silane coupling agents, waxes, etc. These additives may be used individually or in combination of two or more. 【0071】 The moisture-curing polyurethane hot melt resin composition of this disclosure may contain 50% by mass or more, 60% by mass or more, or 70% by mass or more, or 100% by mass or less, 99% by mass or less, 95% by mass or less, 90% by mass or less, or 80% by mass or less, based on the total amount (100% by mass) of the moisture-curing polyurethane hot melt resin composition. The moisture-curing polyurethane hot melt resin composition of this disclosure preferably contains urethane prepolymer (i) as a main component, and may contain only urethane prepolymer (i). 【0072】 The resin composition of this disclosure preferably has an E'(25) / E'(60) ratio of 1.0 to 10.0, more preferably 1.2 to 9.5, even more preferably 1.2 to 9.0, even more preferably 1.5 to 9.0, and even more preferably 1.5 to 8.0. The resin composition of this disclosure can achieve both excellent drop impact resistance and excellent heat creep resistance by having an E'(25) / E'(60) ratio of 1.5 to 8.0 within the above range, i.e., by having a small difference between E'(25) and E'(60). 【0073】 The resin composition of this disclosure preferably has a storage modulus E'(25) of the cured product at 25°C in the range of 30 MPa to 150 MPa, more preferably in the range of 35 MPa to 135 MPa, and even more preferably in the range of 40 MPa to 120 MPa. By having a storage modulus E'(25) of the cured product at 25°C in the above range, the resin composition of this disclosure can have excellent drop impact resistance while maintaining adhesive strength. 【0074】 Furthermore, the resin composition of this disclosure preferably has a storage modulus E'(60) of the cured product at 60°C in the range of 10 MPa to 50 MPa, more preferably in the range of 11 MPa to 45 MPa, and even more preferably in the range of 12 MPa to 40 MPa. The resin composition of this disclosure can have excellent heat creep resistance if the storage modulus E'(60) of the cured product at 60°C is within the above range. 【0075】 The resin composition of this disclosure preferably has a peak top temperature of the loss tangent tanδ of the cured resin composition of -15°C or lower, more preferably -18°C or lower, and even more preferably -20°C or lower. The cured resin composition of this disclosure exhibits improved stress relaxation at room temperature and superior drop impact resistance due to the peak top temperature of the loss tangent tanδ being within the above range. Furthermore, the lower limit of the peak top temperature of the loss tangent tanδ of the cured resin composition of this disclosure is not particularly limited, but a lower limit is preferable, for example, -70°C or higher is preferred, and -50°C or higher is more preferred. 【0076】 The storage modulus E'(25) and E'(60) at 25°C and 60°C of the cured moisture-curing polyurethane hot-melt resin composition are defined as follows: A sheet of the cured moisture-curing polyurethane hot-melt resin composition with a thickness of 100 μm is prepared by heating and melting the moisture-curing polyurethane hot-melt resin composition at 110°C, molding it to a thickness of 100 μm using a roll coater, and leaving it in a constant temperature and humidity chamber at 23°C and 50% RH for 72 hours. The storage modulus and loss tangent of this sheet are measured using a viscoelasticity measuring device (DMS6100, manufactured by SII Nanotechnology Co., Ltd.) under the following conditions. The storage modulus at 25°C is defined as E'(25) [MPa] and the storage modulus at 60°C is defined as E'(60) [MPa]. The temperature at which the loss tangent tanδ measured by the above method peaks below 25°C is defined as the peak top temperature of the loss tangent tanδ of the cured resin composition [°C]. (conditions) Temperature range: -100 to 200°C Heating rate: 5°C / min Frequency: 1Hz Mode: Tensile mode 【0077】 The resin composition of this disclosure preferably has a thixotropy index (TI) in the range of 1.11 to 1.80, more preferably in the range of 1.13 to 1.75, even more preferably in the range of 1.15 to 1.70, and may also be in the range of 1.20 to 1.65, or in the range of 1.25 to 1.60. The thixotropy index (TI) can be used as an indicator of compatibility, and when the thixotropy index (TI) of the resin composition of this disclosure is within the above range, a significant phase separation state between a soft segment such as a polyol and a hard segment such as an isocyanate can be formed within the resin composition of this disclosure after moisture curing, thereby achieving both excellent drop impact resistance and excellent heat creep resistance. 【0078】 The thixotropy index (TI) of the moisture-curing polyurethane hot-melt resin composition is defined as the thixotropy index (TI) at 110°C. After heating a cone-plate viscometer CV-1 (manufactured by Toa Kogyo Co., Ltd.) to 110°C, the moisture-curing polyurethane hot-melt resin composition, heated and melted at 110°C, was placed between the cone and plate, and the melt viscosity η5 and η5 were measured at rotor rotation speeds of 5 rpm and 50 rpm. 50 The value was calculated by measuring [the value] and using the following formula. Thixotropy index (TI) = (Melting viscosity η5 at 5 rpm) / (Melting viscosity η at 50 rpm) 50 ) 【0079】 The moisture-curing polyurethane hot-melt resin composition of this disclosure, by containing a predetermined composition, can form a narrow and thick cured film layer. Specifically, the wettability index of the moisture-curing polyurethane hot-melt resin composition of this disclosure is preferably 30 or less, more preferably 1.0 to 20, and even more preferably 1.0 to 15. By having the wettability index within the above range, the decrease in film thickness and widening of the line width of the coating film of the moisture-curing polyurethane hot-melt resin composition of this disclosure over time can be suppressed, and the application of a narrow, thick film is possible. Furthermore, high adhesive strength and excellent drop impact resistance can be exhibited after curing. 【0080】 The wettability index of a moisture-curing polyurethane hot melt resin composition is calculated using the following formula, when the moisture-curing polyurethane hot melt resin composition is heated and melted at 110°C for 30 minutes, and then applied in a straight line of 25 mm in length on a polycarbonate (PC) plate (size 25 mm x 100 mm) using a dispenser needle with an inner diameter of 0.35 mm heated to 110°C at a processing speed of 50 mm / second, with the line width after 5 seconds being W(5) and the line width after 180 seconds being W(180). Wetting spread index = ({W(180)-W(5)} / W(5))*100 【0081】 The moisture-curing polyurethane hot-melt resin composition of this disclosure can be particularly suitably used as an adhesive for assembling electronic materials. 【0082】 II. Adhesives The adhesive of this disclosure comprises the moisture-curing polyurethane hot-melt resin composition of this disclosure. Details of the moisture-curing polyurethane hot-melt resin composition contained in the adhesive of this disclosure are as described in section I. Moisture-curing polyurethane hot-melt resin composition above. 【0083】 III. Laminates The laminate of the present disclosure comprises at least a substrate and a cured layer of the moisture-curable polyurethane hot-melt resin composition of the present disclosure. 【0084】 Examples of the above-mentioned substrates include resin films such as acrylic resins, urethane resins, silicone resins, epoxy resins, fluororesins, polystyrene resins, polyester resins, polysulfone resins, polyarylate resins, polyvinyl chloride resins, polyvinylidene chloride, cycloolefin resins, polyolefin resins, polyimide resins, alicyclic polyimide resins, cellulose resins, PC (polycarbonate), PBT (polybutylene terephthalate), modified PPE (polyphenylene ether), PEN (polyethylene naphthalate), PET (polyethylene terephthalate), lactic acid polymers, ABS resins, and AS resins; wood-based substrates such as MDF, plywood, and particleboard; fiber-based substrates such as nonwoven fabrics, woven fabrics, and knitted fabrics; and metal substrates such as stainless steel, aluminum, copper, iron, chromium, zinc, duralumin, die-cast metals, and alloys thereof. The above-mentioned substrates may be subjected to surface treatments such as corona treatment, plasma treatment, and primer treatment as needed. If the laminate of the present disclosure has two or more substrates, the two or more substrates may be of the same type or different types. 【0085】 The cured layer described above is a layer obtained by curing the moisture-curable polyurethane hot-melt resin composition of this disclosure. Details of the moisture-curable polyurethane hot-melt resin composition used to form the cured layer, and preferred physical properties of the cured layer, are as described in section "I. Moisture-curable polyurethane hot-melt resin composition" above. 【0086】 The line width and film thickness of the cured layer are not particularly limited, but the line width of the cured layer is preferably in the range of 0.2 mm to 2.0 mm, more preferably in the range of 0.3 mm to 1.5 mm, and even more preferably in the range of 0.5 mm to 1.0 mm. The film thickness of the cured layer is preferably 50% or more of the line width, more preferably 60% or more, and even more preferably 70% or more. The upper limit of the size of the film thickness of the cured layer (ii) relative to the line width is not particularly limited, but for example it can be 300% or less, preferably 200% or less, more preferably 150% or less, and even more preferably 100% or less. 【0087】 One method for forming the above-mentioned cured layer is to melt the moisture-curing polyurethane hot-melt resin composition of this disclosure at 50°C to 130°C, coat it onto a substrate, and then moisture-cur the coating film. Examples of methods for coating the moisture-curing polyurethane hot-melt resin composition include using a roll coater, spray coater, T-die coater, knife coater, comma coater, etc. 【0088】 Furthermore, in this disclosure, since the cured layer can be formed in a narrow and thick film, a method of applying the moisture-curing polyurethane hot melt resin composition by dispensing it from a dispenser is preferably used as the coating method. In this case, the moisture-curing polyurethane hot melt resin composition may be supplied in a container such as a syringe. 【0089】 A method for manufacturing the laminate according to the present disclosure includes coating one substrate with the moisture-curing polyurethane hot-melt resin composition according to the present disclosure, further bonding another substrate onto the coating of the resin composition, and aging for 0.5 to 3 days at a temperature of 20°C to 80°C and a relative humidity of 50% to 90%. Through this aging, the coating of the resin composition becomes a cured layer, and a laminate is obtained in which the two substrates are joined via the cured layer, and the final adhesive strength can be obtained. 【0090】 IV.Electronic equipment The electronic device of this disclosure has two components joined together via a cured layer of the moisture-curing polyurethane hot-melt resin composition described in section I. Moisture-curing polyurethane hot-melt resin composition above. 【0091】 Details of the moisture-curing polyurethane hot-melt resin composition constituting the cured layer in the electronic device of this disclosure, and the method for obtaining the cured layer, are the same as those described in sections "I. Moisture-curing polyurethane hot-melt resin composition" to "III. Laminate" above, and therefore will not be explained here. 【0092】 Furthermore, the components of the electronic device described herein are not particularly limited and include, for example, a housing, a protective panel for an information display unit, an image display module, a display panel component, a semiconductor element, a light-emitting element, an electronic circuit board, a power supply (battery), and the like. 【0093】 V. Method of bonding the substrate The method for bonding adherends according to this disclosure comprises the steps of: melting the moisture-curing polyurethane hot melt resin composition described in section I. Moisture-curing polyurethane hot melt resin composition above, applying it to a first adherend to form a coating film; and bonding the first adherend to a second adherend via the coating film. 【0094】 In the adhesion method of the present disclosure, the method of applying the moisture-curing polyurethane hot melt resin composition is not particularly limited, but a method of application by dispensing from a dispenser is preferred because the resin composition can be applied in a narrow width and thick film. The moisture-curing polyurethane hot melt resin composition is preferably melted at 50°C to 130°C before dispensing. The above moisture-curing polyurethane hot melt resin composition may be supplied in a container such as a syringe. 【0095】 The above-mentioned adherend is not particularly limited, and general-purpose adherends such as metal adherends (specifically SUS, aluminum, etc.), resin adherends, and glass adherends can be used. Specifically, the materials of each adherend are those of the base material exemplified in the section "III. Laminates" above. 【0096】 This disclosure is not limited to the embodiments described above. The embodiments described above are illustrative, and any configuration that is substantially identical to the technical idea described in the claims of this disclosure and produces similar effects is included within the technical scope of this disclosure. [Examples] 【0097】 The present disclosure will be explained in more detail below with reference to examples and comparative examples. 【0098】 [Examples 1-6, Comparative Examples 1-4] In a four-necked flask equipped with a thermometer, stirrer, inert gas inlet, and reflux condenser, the polyol and polyamine raw materials shown in Table 1 were charged in the amounts (parts by mass) indicated in the same table, and dehydrated by heating under reduced pressure at 90°C until the moisture content was 0.05% by mass or less. Next, after cooling the temperature in the reaction vessel to 60°C, diphenylmethane diisocyanate (hereinafter abbreviated as "MDI") was added in the amount (parts by mass) shown in Table 1, and the temperature was raised to 110°C. The reaction was carried out for about 3 hours until the isocyanate group content became constant, thereby obtaining urethane prepolymers (i-1) to (i-10) having isocyanate groups, which were then used as moisture-curable polyurethane hot-melt resin compositions (1) to (10). 【0099】 The abbreviations in Table 1 indicate the following materials. PO(1): Polypropylene glycol, number average molecular weight; 1000, average number of functional groups; 2 PO(2): Polyoxyethylene polyoxypropylene glycol, number-average molecular weight: 4000, EO / PO molar ratio: 10 / 90, average number of functional groups: 2 Ac(1): Polyacrylic polyol obtained by reacting methyl methacrylate, n-butyl methacrylate, and 2-hydroxyethyl methacrylate, number average molecular weight: 20000, glass transition temperature: 70°C. PC(1): Amorphous polycarbonate polyol derived from 1,4-butanediol and 1,6-hexanediol as glycol raw materials, number average molecular weight; 2000 PC(2): A crystalline polycarbonate polyol derived from 1,6-hexanediol as a glycol raw material, with a number-average molecular weight of 2000. PEs(1): Amorphous polyester polyol obtained by reacting neopentyl glycol and adipic acid; number average molecular weight: 2000 Amorphous polyester polyol obtained by reacting PEs(2):2-methyl-1,3-propanediol with adipic acid; number average molecular weight: 2000 Crystalline polyester polyol obtained by reacting PEs(3):1,4-butanediol with adipic acid; number average molecular weight: 1000 Crystalline polyester polyol obtained by reacting PEs(4):1,4-butanediol with adipic acid; number average molecular weight: 2000 Crystalline polyester polyol obtained by reacting PEs(5):1,6-hexanediol with adipic acid; number average molecular weight: 2000 Crystalline polyester polyol obtained by reacting PEs(6):1,6-hexanediol and dodecanediic acid; number average molecular weight: 3500 PA(1):4,4-Diaminodiphenylmethane PA(2):4,4-Methylenebis[N-(1-methylpropyl)aniline] 【0100】 [Method for measuring number-average molecular weight] The number-average molecular weights of the polyols used in the preparation of the urethane prepolymers in the examples and comparative examples are those measured by gel permeation chromatography (GPC) under the following conditions. 【0101】 Measurement device: High-speed GPC device (HLC-8220GPC manufactured by Tosoh Corporation) Columns: The following columns manufactured by Tosoh Corporation were used, connected in series. "TSKgel G5000" (7.8mm I.D. x 30cm) x 1 "TSKgel G4000" (7.8mm I.D. x 30cm) x 1 "TSKgel G3000" (7.8mm I.D. x 30cm) x 1 "TSKgel G2000" (7.8mmI.D. x 30cm) x 1 Detector: RI (Differential Refractometer) Column temperature: 40℃ Eluent: Tetrahydrofuran (THF) Flow rate: 1.0mL / min Injection volume: 100 μL (tetrahydrofuran solution with a sample concentration of 0.4% by mass) Standard samples: Calibration curves were prepared using the following standard polystyrene samples. 【0102】 (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. 【0103】 [Table 1] 【0104】 <Rating> The moisture-curing polyurethane hot-melt resin compositions of the examples and comparative examples were evaluated as follows. The evaluation results are shown in Tables 2 and 3. 【0105】 [1. Normal strength and thermal strength] A moisture-curing polyurethane hot melt resin composition was heated to 110°C for 30 minutes to melt it. Using a dispenser needle with an inner diameter of 0.35 mm (SHOT MASTER 300DS dispenser manufactured by Musashi Engineering Co., Ltd.) heated to 110°C, the composition was applied in a straight line 25 mm long onto a polycarbonate (PC) plate (25 mm x 100 mm) at a processing speed of 50 mm / second. 60 seconds after application, another PC plate (25 mm x 100 mm) was placed on top with a 0.15 mm spacer in between, and the two plates were bonded together so that the overlap joint length of the moisture-curing polyurethane hot melt resin composition was 1 mm. Subsequently, the laminate was left in a constant temperature and humidity chamber at 23°C and 50% humidity for 72 hours to obtain a laminate for measuring normal strength and thermal strength. Furthermore, the moisture-curing polyurethane hot-melt resin composition of Comparative Example 2 had too high a viscosity to be dispensed from the dispenser. 【0106】 The laminate obtained above was measured at a 23°C environment using a benchtop precision universal testing machine (Shimadzu Corporation, Autograph AGS-5kNX) at a tensile speed of 10 mm / min. The maximum breaking strength was divided by the area of ​​the moisture-curing polyurethane hot-melt resin composition to determine the normal strength [MPa]. Furthermore, the obtained laminate was measured at a 60°C environment in the same manner as above. The maximum breaking strength was divided by the area of ​​the moisture-curing polyurethane hot-melt resin composition to determine the hot strength [MPa]. 【0107】 [2. Drop impact resistance] A moisture-curing polyurethane hot-melt resin composition was heated to 110°C for 30 minutes to melt it. Using a dispenser needle with an inner diameter of 0.35 mm (SHOT MASTER 300DS dispenser manufactured by Musashi Engineering Co., Ltd.) heated to 110°C, the mixture was applied in a 1-inch circular pattern onto a polycarbonate (PC) plate (size 50 mm x 90 mm) with a 10 mm diameter hole in the center, at a processing speed of 50 mm / second. 60 seconds after application, another polycarbonate (PC) plate (size 50 mm x 50 mm) was bonded on top with a 0.15 mm spacer in between. The laminate was then left in a constant temperature and humidity chamber at 23°C and 50% RH for 72 hours to obtain a laminate used for measuring drop impact resistance. Furthermore, the moisture-curing polyurethane hot-melt resin composition of Comparative Example 2 had too high a viscosity to be dispensed from the dispenser. 【0108】 The laminate obtained above was subjected to a DuPont drop impact tester, where it was subjected to impacts three times each at a load of 200g and a height of 5cm through a PC board with a 10mm diameter hole in the center, via an impact core. If no delamination of the PC board occurred, the impact was increased by 5cm and the presence or absence of delamination was visually observed, and the height [cm] at which delamination of the PC board occurred was measured. 【0109】 [3. Thixotropy (Thixotropy Index (TI))] A cone-plate viscometer CV-1 (manufactured by Toa Kogyo Co., Ltd.) was heated to 110°C. A moisture-curing polyurethane hot-melt resin composition, heated and melted at 110°C, was placed between the cone and plate, and the melt viscosity was measured at rotor rotation speeds of 5 rpm and 50 rpm. The thixotropy index (TI) was calculated using the following formula. Thixotropy index (TI) = (Melting viscosity at 5 rpm) / (Melting viscosity at 50 rpm) 【0110】 [4. Storage modulus E'(25) and E'(60), and tanδ peak top temperature] A moisture-curing polyurethane hot-melt resin composition, heated and melted at 110°C, was molded to a thickness of 100 μm using a roll coater. The molded product was then left in a constant temperature and humidity chamber at 23°C and 50% RH for 72 hours to obtain a 100 μm thick molded product. The storage modulus and loss tangent of this molded product were measured using a viscoelasticity analyzer (DMS6100, SII Nanotechnology Co., Ltd.) under the following conditions. The storage modulus at 25°C was defined as E'(25) [MPa], and the storage modulus at 60°C as E'(60) [MPa]. The temperature at which the loss tangent tanδ peaks below 25°C was defined as the tanδ peak top temperature [°C]. (conditions) Temperature range: -100 to 200°C Heating rate: 5°C / min Frequency: 1Hz Mode: Tensile mode 【0111】 [5. Wetting Spread Index] A moisture-curing polyurethane hot-melt resin composition was heated and melted at 110°C for 30 minutes. Using a dispenser needle with an inner diameter of 0.35 mm heated to 110°C, the melted resin was applied in a 25 mm long straight line onto a polycarbonate (PC) plate (size 25 mm x 100 mm) at a processing speed of 50 mm / second. The line width after 5 seconds from application was defined as W(5), and the line width after 180 seconds from application was defined as W(180). The value calculated from the following formula was defined as the wetting spread index. Wetting spread index = ({W(180)-W(5)} / W(5))*100 Furthermore, the moisture-curing polyurethane hot-melt resin composition of Comparative Example 2 had too high a viscosity to be dispensed from the dispenser. 【0112】 [Table 2] 【0113】 [Table 3]

Claims

[Claim 1] It contains a urethane prepolymer (i) having an isocyanate group, which is made from at least a polyol (A), a polyisocyanate (B), and a polyamine (C) as raw materials. The polyol (A) comprises at least a polyether polyol (a1) and a polyacrylic polyol (a2), A moisture-curing polyurethane hot-melt resin composition in which the content of the polyamine (C) is in the range of 0.1 parts by mass to 1.0 part by mass per 100 parts by mass of the urethane prepolymer (i). [Claim 2] The moisture-curing polyurethane hot-melt resin composition according to claim 1, wherein the wetting spread index calculated by the method described below is 30 or less. (Wetting spread index) The moisture-curing polyurethane hot melt resin composition is heated and melted at 110°C for 30 minutes, and then applied in a straight line 25 mm long onto a polycarbonate (PC) plate (25 mm x 100 mm) using a dispenser needle with an inner diameter of 0.35 mm heated to 110°C at a processing speed of 50 mm / second. The line width after 5 seconds is W(5), and the line width after 180 seconds is W(180). The value is calculated using the following formula. Wetting spread index = ({W(180) - W(5)} / W(5)) * 100 [Claim 3] The moisture-curing polyurethane hot-melt resin composition according to claim 1, wherein the polyamine (C) is an aromatic polyamine. [Claim 4] The polyether polyol (a1) includes a high molecular weight polyether polyol, The moisture-curing polyurethane hot-melt resin composition according to claim 1, wherein the content of the high molecular weight polyether polyol is in the range of 10 to 50 parts by mass in 100 parts by mass of the raw material of the urethane prepolymer (i). [Claim 5] The moisture-curing polyurethane hot-melt resin composition according to claim 1, wherein the content of the polyacrylic polyol (a2) is in the range of 3 parts by mass to 20 parts by mass in 100 parts by mass of the raw material for the urethane prepolymer (i). [Claim 6] The moisture-curing polyurethane hot-melt resin composition according to claim 1, wherein the polyol (A) further comprises at least one of polyester polyol (a3) ​​and polycarbonate polyol (a4). [Claim 7] The moisture-curing polyurethane hot-melt resin composition according to claim 1, wherein the content of the polyisocyanate (B) is in the range of 10 parts by mass to 40 parts by mass in 100 parts by mass of the raw material for the urethane prepolymer (i). [Claim 8] An adhesive containing the moisture-curing polyurethane hot-melt resin composition according to any one of claims 1 to 7. [Claim 9] A laminate comprising at least a base material and a cured layer of a moisture-curing polyurethane hot-melt resin composition according to any one of claims 1 to 7. [Claim 10] A step of melting the moisture-curing polyurethane hot melt resin composition according to any one of claims 1 to 7, and applying it to a first adherend using a dispenser to form a coating film, A step of bonding the first adherend and the second adherend via the coating film, A method for adhering an object, comprising the following features.

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