Moisture-curing resin compositions and adhesives for electronic equipment

Abstract

A moisture-curable resin composition including a moisture-curable resin, and giving cured objects which have a shear bonding strength of 4 MPa or higher and an elongation at rupture of 600% or higher and have no glass transition point at temperatures of 10°C and higher.

Description

[Technical Field]

[0001] The present invention relates to a moisture-curing resin composition and an adhesive for electronic equipment made from a moisture-curing resin composition. [Background technology]

[0002] Traditionally, adhesive tapes have been commonly used to bond components of portable electronic devices such as smartphones. However, in recent years, moisture-curing resin compositions, which allow for automated production, have come to be used as adhesives. Moisture-curing resin compositions are being investigated for various properties. For example, Patent Document 1 describes a cured body of a photo-moisture-curing resin composition containing a radical polymerizable compound and a moisture-curing resin, which provides a cured body with excellent flexibility and reliability in high-temperature and high-humidity environments, and describes a storage modulus of 1.0 × 10⁻⁶ at 0°C. 7 The Pa is set to be greater than or equal to the storage modulus at 50°C, and the storage modulus at 50°C is 5.0 × 10⁻⁶. 6 It has been shown that it can be set to Pa or less. [Prior art documents] [Patent Documents]

[0003] [Patent Document 1] International Publication No. 2016 / 076407 [Overview of the project] [Problems that the invention aims to solve]

[0004] Incidentally, while portable electronic devices such as smartphones are subjected to significant impact when dropped, the adhesives used in these devices have a small bonding surface area. Furthermore, in recent years, with the miniaturization of electronic devices, the bonding parts have become thinner, resulting in an even smaller bonding surface area. However, conventional moisture-curing resin compositions do not have sufficient impact resistance, and if the bonding area is small, problems may occur such as the components fixed by the moisture-curing resin composition falling off when dropped.

[0005] Therefore, the object of the present invention is to provide a moisture-curable resin composition that can achieve sufficiently high impact resistance. [Means for solving the problem]

[0006] As a result of diligent research, the inventors have found that the above problems can be solved by ensuring that the shear adhesive strength and elongation at break of the cured product are above predetermined values, while also ensuring that the glass transition temperature does not occur in a temperature range of 10°C or higher. Based on this, the inventors have completed the present invention as follows. That is, the present invention provides the following [1] to

[26] . [1] A moisture-curing resin composition containing a moisture-curing resin (A), A moisture-curable resin composition wherein the cured product has a shear adhesive strength of 4 MPa or more, an elongation at break of 600% or more, and does not have a glass transition temperature in a temperature range of 10°C or higher. [2] The moisture-curable resin composition according to [1], wherein the cured product of the moisture-curable resin composition has a glass transition temperature in the temperature range of -20°C or more and less than 10°C. [3] The moisture-curable resin composition according to [1] or [2] above, wherein the cured product of the moisture-curable resin composition has a glass transition temperature in a temperature range of -45°C or lower. [4] A moisture-curing resin composition according to any one of the above [1] to [3], wherein the viscosity measured at 80°C and 20 rpm is 50 Pa·s or less. [5] A moisture-curable resin composition according to any one of the above [1] to [4], further comprising a radical polymerizable compound (B) and a photopolymerization initiator (Y). [6] A moisture-curable resin composition according to any one of the above [1] to [5], comprising 60 parts by mass or more of moisture-curable resin with respect to a total of 100 parts by mass of radical polymerizable compound (B) and moisture-curable resin (A). [7] The moisture-curing resin composition according to any one of the above [1] to [6], wherein the moisture-curing resin (A) is a moisture-curing urethane resin. [8] A moisture-curing resin composition according to any one of the above [1] to [7], used for application by a jet dispenser. [9] A moisture-curing resin composition according to any one of the above [1] to [8], wherein the viscosity measured at 80°C and 20 rpm is 30 Pa·s or less.

[10] The moisture-curable resin composition according to any one of the above [1] to [9], wherein the cured product of the moisture-curable resin composition has a storage modulus of 7 MPa or more and 50 MPa or less.

[11] The moisture-curable resin composition according to any one of the above [1] to

[10] , wherein the moisture-curable resin (A) is a moisture-curable urethane resin, and the moisture-curable urethane resin has at least one of a polyester skeleton, a polyether skeleton, a polyalkylene skeleton, and a polycarbonate skeleton.

[12] The moisture-curing resin composition according to

[11] , wherein the moisture-curing urethane resin has at least one of a polyester skeleton and a polyether skeleton.

[13] The moisture-curable resin composition according to any one of the above [1] to

[12] , wherein the moisture-curable resin (A) is a moisture-curable urethane resin, and the moisture-curable urethane resin is a reaction product of a polyol compound and a polyisocyanate compound.

[14] The moisture-curing resin composition according to

[13] above, wherein the polyol compound comprises a polyester polyol obtained from a polycarboxylic acid and a polyol.

[15] The moisture-curing resin composition according to

[13] or

[14] above, wherein the polyol compound comprises at least one selected from the group consisting of propylene glycol, ring-opening polymer compounds of tetrahydrofuran compounds, and ring-opening polymer compounds of tetrahydrofuran compounds having substituents.

[16] The moisture-curing resin composition according to any one of the above [1] to

[15] , wherein the weight-average molecular weight of the moisture-curing resin (A) is 1,000 or more and 100,000 or less.

[17] A moisture-curable resin composition according to any one of the above [1] to

[16] , further comprising at least a radical polymerizable compound (B).

[18] The moisture-curing resin composition according to

[17] above, wherein the radical polymerizable compound (B) comprises at least one selected from the group consisting of (meth)acrylic acid ester compounds, epoxy (meth)acrylate, and urethane (meth)acrylate.

[19] The moisture-curing resin composition according to

[17] or

[18] above, wherein the radical polymerizable compound (B) comprises at least one selected from the group consisting of urethane (meth)acrylate and alkyl (meth)acrylate.

[20] The moisture-curable resin composition according to any one of the above

[17] to

[19] , wherein the content of the radical polymerizable compound (B) is 20 parts by mass or more and 50 parts by mass or less with respect to 100 parts by mass of the total amount of moisture-curable resin (A) and radical polymerizable compound (B).

[21] The moisture-curable resin composition according to any one of the above

[17] to

[20] , further comprising a photopolymerization initiator (Y), wherein the content of the photopolymerization initiator (Y) is 0.01 parts by mass or more and 10 parts by mass or less per 100 parts by mass of the radical polymerizable compound.

[22] A moisture-curing resin composition according to any one of the above [1] to

[21] , further containing a crosslinking agent (X).

[23] An adhesive for electronic equipment comprising a moisture-curing resin composition as described in any one of the above items [1] to

[22] .

[24] A cured body of a moisture-curing resin composition as described in any one of the above items [1] to

[22] .

[25] A method of joining adherends by placing a moisture-curing resin composition described in any one of the above items [1] to

[22] between adherends.

[26] A method of applying the moisture-curing resin composition described in any one of the above items [1] to

[22] using a dispenser. [Effects of the Invention]

[0007] According to the present invention, it is possible to provide a moisture-curable resin composition that can achieve sufficiently high impact resistance. [Brief explanation of the drawing]

[0008] [Figure 1]It is a schematic diagram for explaining a method for measuring shear adhesion strength. [Figure 2] It is a schematic diagram for explaining a method for evaluating impact resistance.

Embodiments for Carrying Out the Invention

[0009] Hereinafter, the present invention will be described in detail. [Moisture-curable resin composition] The moisture-curable resin composition of the present invention is a composition containing a moisture-curable resin (A). The cured product of the moisture-curable resin composition of the present invention has a shear adhesion strength of 4 MPa or more, an elongation at break of 600% or more, and does not have a glass transition point in a temperature range of 10°C or higher. The moisture-curable resin composition of the present invention can ensure sufficiently high impact absorbency by adjusting so that both the storage elastic modulus and the elongation at break of the cured product are high as described above and the cured product does not have a glass transition point in a temperature range of 10°C or higher. Therefore, for example, even when used as an adhesive for fixing members constituting a portable electronic device or the like, when the portable electronic device or the like falls, problems such as the constituent members fixed by the moisture-curable resin composition of the present invention falling off are less likely to occur.

[0010] As described above, the moisture-curable resin composition of the present invention has at least a moisture-curable resin (A) and has moisture-curing properties. The moisture-curable resin composition has moisture-curing properties, making it easy to sufficiently increase the adhesive force. In addition, the moisture-curable resin composition of the present invention preferably contains a radically polymerizable compound (B) and a photopolymerization initiator (Y) in addition to the moisture-curable resin (A). In this case, the moisture-curable resin composition becomes a photo-moisture-curable resin composition that cures by light irradiation and moisture. Since the photo-moisture-curable resin composition has excellent adhesive performance even when cured without heating, it can prevent electronic components or the like in the adhesive part or around the adhesive part from being damaged by heating during curing and can provide excellent adhesive performance. A photo- and moisture-curable resin composition can be first cured with light to create a B-stage state with relatively low adhesive strength (tackiness), and then further cured by moisture by being left in the air or elsewhere, resulting in a cured product with sufficiently high adhesive strength.

[0011] (Shear bonding strength of the cured material) In the present invention, the shear adhesive strength of the cured product of the moisture-curable resin composition is 4 MPa or higher, as described above. If the shear adhesive strength is less than 4 MPa, the shock absorption cannot be sufficiently high, and when electronic devices are dropped, problems such as the components fixed by the moisture-curable resin composition of the present invention falling off are likely to occur. Furthermore, problems such as the inability to firmly bond components of electronic devices to each other are also likely to occur. The shear adhesive strength of the cured product of the moisture-curable resin composition is preferably 4.2 MPa or higher, and more preferably 5 MPa or higher, from the viewpoint of impact absorption and adhesion. Furthermore, although the shear adhesive strength of the cured product of the moisture-curable resin composition is not particularly limited, it is preferably 15 MPa or lower, more preferably 12 MPa or lower, and even more preferably 10 MPa or lower, from the viewpoint of easily increasing the elongation at break and easily lowering the glass transition temperature (Tg). The shear bond strength can be adjusted as appropriate depending on the type of moisture-curing resin (A), the type of radical polymerizable compound (B), and their respective content.

[0012] In this invention, the above-mentioned shear adhesive strength is measured by the following adhesion test. As shown in Figures 1(a) and (b), a moisture-curable resin composition 10 is applied to an aluminum substrate 11 to a width of 1.0 ± 0.1 mm, a length of 25 ± 2 mm, and a thickness of 0.4 ± 0.1 mm. A glass plate 12 is then placed on top of the moisture-curable resin composition 10 to prepare a sample 13 for adhesion testing. The adhesion test sample 13 is formed by bonding the aluminum substrate 11 and the glass plate 12 together by curing the moisture-curable resin composition 10. After the moisture-curable resin composition has cured, the prepared adhesion test sample 13 is left in a 25°C, 50% RH atmosphere for 25 minutes. Then, in a 25°C, 50% RH atmosphere, it is pulled in the shear direction S at a speed of 10 mm / min using a tensile testing machine, and the strength at which the aluminum substrate 11 and the glass plate 12 peel off is measured to determine the shear adhesion strength.

[0013] Here, when preparing samples for adhesion testing, the curing conditions for the moisture-curable resin composition should be such that the moisture-curable resin composition of the present invention is fully cured. Samples should be prepared under the following conditions depending on the curing mechanism. In the case of a moisture-curing resin composition (but without thermosetting or photocuring properties), the composition was applied to an aluminum substrate using a dispenser to a width of 1.0 ± 0.1 mm, a length of 25 ± 2 mm, and a thickness of 0.4 ± 0.1 mm. A glass plate was then bonded to the aluminum substrate, and a 100 g weight was placed on it for 10 seconds to allow it to adhere. After removing the weight, the mixture was left to moisture-cur for 7 days at 25°C and 50% RH to obtain a sample for adhesion evaluation. In the case of a photo-moisture-curable resin composition, first, using a dispenser, the resin is applied to an aluminum substrate to a width of 1.0 ± 0.1 mm, a length of 25 ± 2 mm, and a thickness of 0.4 ± 0.1 mm. Then, under conditions of 25°C and 50% RH, it is cured with a UV-LED (wavelength 365 nm) at a rate of 1000 mJ / cm². 2 The material is photocured by irradiation. Then, a glass plate is bonded to an aluminum substrate, a 100g weight is placed on it for 10 seconds to allow it to adhere, and after removing the weight, it is left to cure by moisture at 25°C and 50% RH for 7 days to obtain a sample for adhesion evaluation.

[0014] (Elongation at break of hardened material) In the present invention, the cured product of the moisture-curable resin composition has a breaking elongation of 600% or more. If the breaking elongation is less than 600%, the impact resistance will be insufficient, and if an electronic device or the like is subjected to a large impact such as dropping, problems such as peeling off the components fixed by the moisture-curable resin composition of the present invention will occur. From the viewpoint of sufficiently increasing impact resistance, the breaking elongation is preferably 700% or more, more preferably 800% or more, and even more preferably 900% or more. Furthermore, while the above-mentioned elongation at break is not particularly limited, from the viewpoint of easily increasing the shear bonding strength, it is preferably 1500% or less, more preferably 1300% or less, and even more preferably 1150% or less. The elongation at break can be adjusted as appropriate depending on the type of moisture-curable resin (A), the type of radical polymerizable compound (B), and their respective content. The elongation at break of the cured material is measured by the following method: A moisture-curable resin composition is poured into a dumbbell-shaped (Type 6 as defined in "JIS K6251") silicone rubber mold with a hole, and cured to obtain a Type 6 dumbbell-shaped test piece (cured sample). For moisture-curable resin compositions (but not thermosetting or photocuring), the curing conditions are as follows: moisture curing is performed by leaving the material at 25°C and 50RH% for 7 days. For photo-moisture-curable resin compositions, curing is performed at 25°C and 50RH% using a UV-LED (wavelength 365nm) at 1000mJ / cm². 2 The material is photocured by irradiation, and then moisture-cured by leaving it at 25°C and 50RH% for 7 days. The resulting test specimens are then pulled at a tensile speed of 50 mm / min using a tensile testing machine in a 25°C environment, and the elongation at break is measured.

[0015] (Glass transition temperature of hardened material) In the present invention, the cured product of the moisture-curable resin composition does not have a glass transition temperature in the temperature range of 10°C or higher. If the glass transition temperature is in the temperature range of 10°C or higher, even if the elongation at break and shear adhesive strength are set to a certain value or higher as described above, the impact resistance cannot be sufficiently high. Therefore, when an impact is applied, such as by dropping, problems such as peeling off the components fixed by the moisture-curable resin composition of the present invention may occur. The principle that impact resistance cannot be sufficiently high when the glass transition temperature is in the temperature range of 10°C or higher is not clear, but it is thought to be because the ability to follow high-speed deformation decreases, resulting in a decrease in impact resistance.

[0016] The cured product of the moisture-curable resin composition of the present invention preferably has a glass transition temperature (hereinafter also referred to as "Tg1") in a temperature range of -20°C or higher and less than 10°C. Having a glass transition temperature in the above temperature range makes it easier to lower the viscosity and improve coatability, and to maintain good shape retention after coating. From these viewpoints, the glass transition temperature (Tg1) is more preferably -10°C or higher, even more preferably -5°C or higher, and even more preferably 9°C or lower.

[0017] Furthermore, in the present invention, the cured product of the moisture-curable resin composition may, from the viewpoint of impact resistance, have a glass transition temperature (hereinafter also referred to as "Tg2") in a temperature range of -30°C or lower, but it is preferable that the glass transition temperature (Tg2) be in a temperature range of -45°C or lower. Having a glass transition temperature in a temperature range of -45°C or lower allows for excellent impact resistance even when the viscosity is lowered to improve coatability. From the viewpoint of coatability and impact resistance, it is more preferable that the cured product of the moisture-curable resin composition of the present invention has a glass transition temperature (Tg2) in a temperature range of -50°C or lower. The glass transition temperature (Tg2) is not particularly limited, but may be, for example, -80°C or higher, -75°C or higher, or -70°C or higher.

[0018] Furthermore, it is preferable that the cured product of the moisture-curable resin composition of the present invention has both of the above glass transition temperatures (Tg1, Tg2). Having these two glass transition temperatures (Tg1, Tg2) allows for a good balance of impact resistance, coatability, and shape retention. In this invention, by including a radical polymerizable compound (B) in addition to a moisture-curable resin (A) and making them immiscible, it becomes easier to obtain a product that has the two glass transition points described above. The method for making them immiscible is not particularly limited, and the types of moisture-curable resin (A) and radical polymerizable compound (B) can be appropriately selected. However, if a moisture-curable resin (A) having a polyether skeleton is used, it is easier for it to become immiscible with the radical polymerizable compound (B), and the cured product is more likely to have two glass transition points.

[0019] Furthermore, the glass transition temperature (Tg1) on the higher temperature side can be adjusted to the desired range described above by appropriately selecting the components of the radical polymerizable compound (B). Similarly, the glass transition temperature (Tg2) on the lower temperature side can be adjusted to the desired range described above by appropriately selecting the type of moisture-curable resin (A), etc. Therefore, by appropriately adjusting the components of the radical polymerizable compound (B), it is possible to avoid having a glass transition temperature in the temperature range above 10°C, as described above. Furthermore, the cured product of the moisture-curing resin composition may have three or more glass transition points, as long as the temperature is below 10°C. The glass transition point is defined as the temperature at which the maximum loss tangent (tanδ) obtained by dynamic viscoelasticity measurement occurs, specifically the temperature at which the maximum value attributable to micro-Brownian motion appears. This measurement should be performed on a cured sample prepared from a moisture-curing resin composition using a dynamic viscoelasticity measuring device. The detailed procedure for preparing the cured sample is described later.

[0020] (Storage modulus) In the present invention, the cured product of the moisture-curable resin composition preferably has a storage modulus of 7 MPa or more and 50 MPa or less. When the storage modulus is within the above range, it tends to have excellent impact resistance. It also tends to have high adhesive strength. From these viewpoints, the storage modulus is preferably 8 MPa or more, more preferably 9 MPa or more, and preferably 40 MPa or less, more preferably 20 MPa or less. The storage modulus can be adjusted as appropriate depending on the type of moisture-curing resin (A), the type of radical polymerizable compound (B), and their respective content.

[0021] In this invention, the storage modulus of the cured product is measured by the following method. A moisture-curing resin composition is poured into a Teflon® mold measuring 3 mm in width, 30 mm in length, and 1 mm in thickness, and cured to obtain a cured sample. The dynamic viscoelasticity of the obtained cured sample is measured using a dynamic viscoelasticity measuring device in the range of -100 to 150°C, and the storage modulus at 25°C is determined.

[0022] Furthermore, for the preparation of cured samples for measuring the glass transition temperature and storage modulus, the curing of moisture-curable resin compositions only needs to be fully cured. However, the curing method should be as follows, depending on the curing mechanism. For example, in the case of photo-moisture-curable resin compositions, a UV-LED (wavelength 365 nm) is used, and ultraviolet light is applied at 1000 mJ / cm² in an environment of 25°C and 50 RH%. 2 The process involves photocuring by irradiation, followed by moisture curing by leaving the material in an environment of 25°C and 50% RH for 7 days. In the case of moisture-curable resin compositions (that are not thermosetting or photocurable), the process is carried out in the same manner as above, except that the photocuring step is omitted.

[0023] (Viscosity of moisture-curing resin compositions) The viscosity of the moisture-curable resin composition of the present invention, as measured at 80°C and 20 rpm, is preferably 50 Pa·s or less. By reducing the viscosity to 50 Pa·s or less, the coatability is improved, and the moisture-curable resin composition can be applied in a fine line onto the substrate using various coating devices, particularly jet dispensers. Therefore, it can be suitably used for portable electronic devices and the like. Furthermore, the viscosity of the moisture-curable resin composition of the present invention, measured at 80°C and 20 rpm, is more preferably 30 Pa·s or less, even more preferably 20 Pa·s or less, and even more preferably 15 Pa·s or less, from the above viewpoint. By adjusting the viscosity to 20 Pa·s or less, and especially 15 Pa·s or less, it can be applied in a fine line with high coating accuracy using a jet dispenser or the like. In addition, the above viscosity is not particularly limited, but from the viewpoint of the ability to maintain a certain shape of the moisture-curable resin composition after application (shape retention), for example, 0.5 Pa·s or more is preferred, 1.0 Pa·s or more is more preferred, and 2.0 Pa·s or more is even more preferred.

[0024] Next, the components used in the moisture-curing resin composition of the present invention will be described.

[0025] (Moisture-curing resin (A)) The moisture-curable resin composition contains a moisture-curable resin (A). Examples of moisture-curable resin (A) used in the present invention include moisture-curable urethane resin, hydrolyzable silyl group-containing resin, and moisture-curable cyanoacrylate resin. Among these, moisture-curable urethane resin and hydrolyzable silyl group-containing resin are preferred, and moisture-curable urethane resin is more preferred. Using a moisture-curable urethane resin makes it easier to improve the elongation at break of the cured product.

[0026] Moisture-curing urethane resins have isocyanate groups in addition to urethane bonds. Moisture-curing urethane resins harden when the isocyanate groups in the molecule react with moisture in the air or on the adherend. Moisture-curing urethane resins may have only one isocyanate group per molecule, or two or more. In particular, it is preferable that the molecule has isocyanate groups at both ends of the main chain.

[0027] Moisture-curing urethane resins can be obtained by reacting a polyol compound having two or more hydroxyl groups in one molecule with a polyisocyanate compound having two or more isocyanate groups in one molecule. The reaction between the above polyol compound and the polyisocyanate compound is usually carried out in the range of [NCO] / [OH] = 2.0 to 2.5, where the molar ratio of hydroxyl groups (OH) in the polyol compound to isocyanate groups (NCO) in the polyisocyanate compound is in the range of [NCO] / [OH].

[0028] Moisture-curing urethane resins may have a polyester skeleton, a polyether skeleton, a polyalkylene skeleton, a polycarbonate skeleton, etc., and among these, from the viewpoint of increasing the elongation at break and improving impact resistance, it is preferable to have at least one of a polyester skeleton and a polyether skeleton, and it may also have both. When a moisture-curing urethane resin has both a polyester skeleton and a polyether skeleton, it may have both in one molecule, but it is preferable to use a moisture-curing urethane resin having a polyester skeleton and a moisture-curing urethane resin having a polyether skeleton in combination. Furthermore, from the viewpoint of improving impact resistance, making it easier to create a low-viscosity composition, and easily creating two or more glass transition temperatures, it is more preferable that the moisture-curing urethane resin is a moisture-curing urethane resin having a polyether skeleton.

[0029] The type of skeleton a moisture-curing urethane resin has is determined by the polyol compound used. Examples of polyol compounds used as raw materials for moisture-curing urethane resins include polyester polyols, polyether polyols, polyalkylene polyols, and polycarbonate polyols. By using each of these, moisture-curing urethane resins can have a polyester skeleton, a polyether skeleton, a polyalkylene skeleton, and a polycarbonate skeleton, respectively. Therefore, at least one polyol compound selected from polyester polyols and polyether polyols is preferred, with polyether polyols being more preferred. These polyol compounds may be used individually or in combination of two or more.

[0030] Examples of the above-mentioned polyester polyols include polyester polyols obtained by the reaction of a polycarboxylic acid with a polyol, and poly-ε-caprolactone polyols obtained by ring-opening polymerization of ε-caprolactone. Examples of polycarboxylic acids that serve as raw materials for polyester polyols include terephthalic acid, isophthalic acid, 1,5-naphthalic acid, 2,6-naphthalic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, decamethylenedicarboxylic acid, and dodecamethylenedicarboxylic acid. Examples of polyols used as raw materials for polyester polyols include ethylene glycol, propylene glycol, 1,3-propanediol, 1,4-butanediol, neopentyl glycol, 1,5-pentanediol, 1,6-hexanediol, diethylene glycol, and cyclohexanediol.

[0031] Examples of polyether polyols include ring-opened polymers of ethylene glycol, propylene glycol, and tetrahydrofuran, ring-opened polymers of 3-methyltetrahydrofuran, and random copolymers or block copolymers of these or their derivatives, as well as bisphenol-type polyoxyalkylene modified products. Here, the bisphenol-type polyoxyalkylene modified product is a polyether polyol obtained by adding an alkylene oxide (e.g., ethylene oxide, propylene oxide, butylene oxide, isobutylene oxide, etc.) to the active hydrogen portion of the bisphenol-type molecular skeleton. The polyether polyol may be a random copolymer or a block copolymer. Preferably, the above bisphenol-type polyoxyalkylene modified product has one or more alkylene oxides added to both ends of the bisphenol-type molecular skeleton. The bisphenol type is not particularly limited, and examples include type A, type F, type S, etc., with bisphenol type A being preferred.

[0032] Examples of polyalkylene polyols include polybutadiene polyols, hydrogenated polybutadiene polyols, and hydrogenated polyisoprene polyols. Examples of polycarbonate polyols include polyhexamethylene carbonate polyol and polycyclohexanedimethylene carbonate polyol.

[0033] The polyol used as a raw material for moisture-curing urethane resin preferably has an average molecular weight of 500 or more, more preferably 1500 or more, even more preferably 2500 or more, preferably 15000 or less, more preferably 8000 or less, and even more preferably 4000 or less. By setting the average molecular weight of the polyol to be above the above lower limit, the glass transition temperature (especially Tg2) can be lowered. Furthermore, by keeping it within the above range, the shear adhesive strength and elongation at break can be improved in a balanced manner. The average molecular weight can be determined by measuring the hydroxyl value (mgKOH / g) and using the following formula. Number-average molecular weight = Hydroxyl value × N × 1,000 / 56.11 N: Average number of functional groups in polyols The hydroxyl value should be measured according to JIS K 1557-1.

[0034] Moisture-curing urethane resins are preferably obtained using a polyol compound having the structure represented by the following formula (1). By using a polyol compound having the structure represented by the following formula (1), it becomes easier to achieve high elongation at break while maintaining good shear bonding strength. Furthermore, it becomes easier to adjust the storage modulus to the desired range described above. In particular, polyether polyols made from propylene glycol, ring-opening polymers of tetrahydrofuran (THF) compounds, or ring-opening polymers of tetrahydrofuran compounds having substituents such as methyl groups are preferred. Ring-opening polymers of tetrahydrofuran compounds are more preferred, and polytetramethylene ether glycol is particularly preferred. Polytetramethylene ether glycol has a linear structure, which makes it easier to improve adhesive strength. Furthermore, it is preferable to use propylene glycol in combination with polytetramethylene ether glycol as the polyol compound. Therefore, the moisture-curing urethane resin may contain both a moisture-curing urethane resin obtained from polytetramethylene ether glycol and a moisture-curing urethane resin obtained from propylene glycol.

[0035] [ka] In formula (1), R represents a hydrogen atom, a methyl group, or an ethyl group, l is an integer from 0 to 5, m is an integer from 1 to 500, and n is an integer from 1 to 10. l is preferably between 0 and 4. Note that when l is 0, it means that the carbon bonded to R is directly bonded to oxygen. Here, m is preferably 20 to 300, and more preferably 30 to 100. By setting m to be above the lower limit, the glass transition temperature (especially Tg2) can be lowered. Furthermore, by setting m within the above range, the shear bonding strength and fracture elongation can be improved in a balanced manner. Furthermore, among the above, it is more preferable that the sum of n and l is 1 or more, more preferable that it is 2 or more, even more preferable that it is between 3 and 6, and most preferable that it is 3. Furthermore, R is more preferably a hydrogen atom or a methyl group, and a hydrogen atom is particularly preferred. Therefore, the structural unit represented by formula (1) is preferably a linear chain. The linear structure of the structural unit represented by formula (1) allows for high shear adhesion strength. Furthermore, the moisture-curing urethane resin obtained from the linear polyether polyol described above, such as the moisture-curing urethane resin obtained from polytetramethylene ether glycol, is preferably 50% to 100% by mass, and more preferably 70% to 100% by mass, based on the total amount of moisture-curing resin (A).

[0036] Aromatic polyisocyanate compounds and aliphatic polyisocyanate compounds are preferably used as polyisocyanate compounds that serve as raw materials for moisture-curing urethane resins. Examples of aromatic polyisocyanate compounds include diphenylmethane diisocyanate, liquid modified diphenylmethane diisocyanate, polymeric MDI, tolylene diisocyanate, and naphthalene-1,5-diisocyanate. Examples of aliphatic polyisocyanate compounds include hexamethylene diisocyanate, trimethylhexamethylene diisocyanate, lysine diisocyanate, norbornane diisocyanate, transcyclohexane-1,4-diisocyanate, isophorone diisocyanate, hydrogenated xylylene diisocyanate, hydrogenated diphenylmethane diisocyanate, cyclohexane diisocyanate, bis(isocyanate-methyl)cyclohexane, and dicyclohexylmethane diisocyanate. Among the polyisocyanate compounds, diphenylmethane diisocyanate and its modified products are preferred from the viewpoint of being able to achieve high adhesive strength after complete curing. Polyisocyanate compounds may be used individually or in combination of two or more.

[0037] The moisture-curable urethane resin may also preferably contain a compound having a urethane bond, an isocyanate group, and a reactive double bond at its terminal (hereinafter also referred to as "reactive double bond-containing urethane resin"). By including the above reactive double bond-containing urethane resin as the moisture-curable urethane resin, the cured product is more likely to have a glass transition temperature in the temperature range of -20°C to less than 10°C, and the impact resistance of the cured product is improved. In this specification, "terminal" refers to the end of the main chain. Furthermore, although the above reactive double bond is a radical polymerizable group, in this specification, the above reactive double bond-containing urethane resin is treated as a moisture-curable urethane resin and not a radical polymerizable compound.

[0038] In reactive double-bond-containing urethane resins, it is preferable that the proportion of isocyanate groups in the structure is 0.8% by mass or less. When the proportion of isocyanate groups in the structure is 0.8% by mass or less, it is easier to improve impact resistance. More preferably, in reactive double-bond-containing urethane resins, the proportion of isocyanate groups in the structure is 0.5% by mass or less. Furthermore, from the viewpoint of moisture curing properties, it is preferable that in reactive double-bond-containing urethane resins, the proportion of isocyanate groups in the structure is 0.1% by mass or more.

[0039] The content of the reactive double bond-containing urethane resin is preferably 0.5 parts by mass or more, more preferably 1 part by mass or more, and preferably 20 parts by mass or less, per 100 parts by mass of the moisture-curable urethane resin. When the content of the reactive double bond-containing urethane resin is within the above range, it exhibits excellent impact resistance and moisture-curing properties.

[0040] The hydrolyzable silyl group-containing resin used in this invention hardens when the hydrolyzable silyl groups within the molecule react with moisture in the air or on the adherend. A hydrolyzable silyl group-containing resin may have only one hydrolyzable silyl group per molecule, or it may have two or more. In particular, it is preferable that the molecule has hydrolyzable silyl groups at both ends of the main chain. Furthermore, the above-mentioned hydrolyzable silyl group-containing resin does not include those having isocyanate groups.

[0041] A hydrolyzable silyl group is represented by the following formula (2). [ka] In formula (2), R 1 Each of these independently comprises an alkyl group having 1 to 20 carbon atoms, which may be substituted, an aryl group having 6 to 20 carbon atoms, an aralkyl group having 7 to 20 carbon atoms, or -OSiR 2 3(R 2 Each of the three elements is independently a hydrocarbon group having 1 to 20 carbon atoms (represented by the formula (2)). In formula (2), each of the three elements is independently a hydroxyl group or a hydrolyzable group. Furthermore, in formula (2), a is an integer from 1 to 3.

[0042] The above hydrolyzable groups are not particularly limited and include, for example, halogen atoms, alkoxy groups, alkenyloxy groups, aryloxy groups, acyloxy groups, ketoxymate groups, amino groups, amide groups, acid amide groups, aminooxy groups, mercapto groups, etc. Among these, halogen atoms, alkoxy groups, alkenyloxy groups, and acyloxy groups are preferred due to their high activity. Furthermore, alkoxy groups such as methoxy groups and ethoxy groups are more preferred because they are milder in hydrolysis and easier to handle, with methoxy groups and ethoxy groups being even more preferred. In addition, from the viewpoint of safety, ethoxy groups and isopropenoxy groups are preferred, as the compounds eliminated by the reaction are ethanol and acetone, respectively.

[0043] The above-mentioned hydroxyl groups or hydrolyzable groups can be bonded to one silicon atom in a range of 1 to 3 groups. If two or more of the above-mentioned hydroxyl groups or hydrolyzable groups are bonded to one silicon atom, those groups may be the same or different.

[0044] In formula (2) above, a is preferably 2 or 3 from the viewpoint of curability, and particularly preferably 3. Furthermore, from the viewpoint of storage stability, a is preferably 2. In addition, R in the above formula (2) 1 Examples thereof include alkyl groups such as methyl group and ethyl group, cycloalkyl groups such as cyclohexyl group, aryl groups such as phenyl group, aralkyl groups such as benzyl group, trimethylsiloxy group, chloromethyl group, methoxymethyl group and the like. Among them, a methyl group is preferable.

[0045] Examples of the hydrolyzable silyl group include methyldimethoxysilyl group, trimethoxysilyl group, triethoxysilyl group, tris(2-propenyloxy)silyl group, triacetoxysilyl group, (chloromethyl)dimethoxysilyl group, (chloromethyl)diethoxysilyl group, (dichloromethyl)dimethoxysilyl group, (1-chloroethyl)dimethoxysilyl group, (1-chloropropyl)dimethoxysilyl group, (methoxymethyl)dimethoxysilyl group, (methoxymethyl)diethoxysilyl group, (ethoxymethyl)dimethoxysilyl group, (1-methoxyethyl)dimethoxysilyl group, (aminomethyl)dimethoxysilyl group, (N,N-dimethylaminomethyl)dimethoxysilyl group, (N,N-diethylaminomethyl)dimethoxysilyl group, (N,N-diethylaminomethyl)diethoxysilyl group, (N-(2-aminoethyl)aminomethyl)dimethoxysilyl group, (acetoxymethyl)dimethoxysilyl group, (acetoxymethyl)diethoxysilyl group and the like.

[0046] Examples of the hydrolyzable silyl group-containing resin include hydrolyzable silyl group-containing (meth)acrylic resin, organic polymer having a hydrolyzable silyl group at the molecular chain terminal or molecular chain terminal site, hydrolyzable silyl group-containing polyurethane resin and the like. The hydrolyzable silyl group-containing (meth)acrylic resin preferably has a repeating structural unit derived from a hydrolyzable silyl group-containing (meth)acrylate ester and / or (meth)acrylic acid alkyl ester in the main chain.

[0047] Examples of hydrolyzable silyl group-containing (meth)acrylic acid esters include 3-(trimethoxysilyl)propyl (meth)acrylate, 3-(triethoxysilyl)propyl (meth)acrylate, 3-(methyldimethoxysilyl)propyl (meth)acrylate, 2-(trimethoxysilyl)ethyl (meth)acrylate, 2-(triethoxysilyl)ethyl (meth)acrylate, 2-(methyldimethoxysilyl)ethyl (meth)acrylate, trimethoxysilylmethyl (meth)acrylate, triethoxysilylmethyl (meth)acrylate, and (methyldimethoxysilyl)methyl (meth)acrylate. Examples of the alkyl (meth)acrylate esters mentioned above include methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, tert-butyl (meth)acrylate, n-pentyl (meth)acrylate, n-hexyl (meth)acrylate, cyclohexyl (meth)acrylate, n-heptyl (meth)acrylate, n-octyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, n-nonyl (meth)acrylate, n-decyl (meth)acrylate, n-dodecyl (meth)acrylate, and stearyl (meth)acrylate. Specific examples of methods for producing hydrolyzable silyl group-containing (meth)acrylic resins include the synthesis method for hydrolyzable silicon group-containing (meth)acrylic acid ester polymers described in International Publication No. 2016 / 035718.

[0048] The organic polymer having a hydrolyzable silyl group at the end of the molecular chain or at the end of the molecular chain has a hydrolyzable silyl group at at least one of the ends of the main chain and the ends of the side chains. The skeletal structure of the main chain described above is not particularly limited and examples include saturated hydrocarbon polymers, polyoxyalkylene polymers, (meth)acrylic acid ester polymers, and the like.

[0049] Examples of the polyoxyalkylene polymers mentioned above include polymers having a polyoxyethylene structure, a polyoxypropylene structure, a polyoxybutylene structure, a polyoxytetramethylene structure, a polyoxyethylene-polyoxypropylene copolymer structure, or a polyoxypropylene-polyoxybutylene copolymer structure. A specific method for producing the above-mentioned organic polymer having hydrolyzable silyl groups at the molecular chain ends or molecular chain terminal sites is the method for synthesizing organic polymers having crosslinkable silyl groups only at the molecular chain ends or molecular chain terminal sites, as described in International Publication No. 2016 / 035718. Another method for producing the above-mentioned organic polymer having hydrolyzable silyl groups at the molecular chain ends or molecular chain terminal sites is the method for synthesizing reactive silicon group-containing polyoxyalkylene polymers, as described in International Publication No. 2012 / 117902.

[0050] Methods for producing the above-mentioned hydrolyzable silyl group-containing polyurethane resin include, for example, a method in which a silyl group-containing compound, such as a silane coupling agent, is further reacted when a polyol compound and a polyisocyanate compound are reacted to produce a polyurethane resin. Specifically, examples include the method for synthesizing a urethane oligomer having a hydrolyzable silyl group described in Japanese Patent Application Publication No. 2017-48345.

[0051] Examples of the silane coupling agents mentioned above include vinyltrichlorosilane, vinyltriethoxysilane, vinyltris(β-methoxyethoxy)silane, β-(3,4-epoxycyclohexyl)-ethyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, γ-methacryloxypropyltrimethoxysilane, N-(β-aminoethyl)-γ-aminopropyltrimethoxysilane, N-(β-aminoethyl)-γ-aminopropyltrimethyldimethoxysilane, N-phenyl-γ-aminopropyltrimethoxysilane, γ-chloropropyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-aminopropyltrimethoxysilane, 3-isocyanatetopropyltrimethoxysilane, and 3-isocyanatetopropyltriethoxysilane. Among these, γ-mercaptopropyltrimethoxysilane, 3-isocyanatetopropyltrimethoxysilane, and 3-isocyanatetopropyltriethoxysilane are preferred. These silane coupling agents may be used individually or in combination of two or more.

[0052] Furthermore, the moisture-curing urethane resin may have both isocyanate groups and hydrolyzable silyl groups. It is preferable to first obtain a moisture-curing urethane resin having both isocyanate groups using the method described above, and then react the moisture-curing urethane resin with a silane coupling agent. The details of the moisture-curable urethane resin having an isocyanate group are as described above. The silane coupling agent used for moisture curing can be appropriately selected from those listed above, but from the viewpoint of reactivity with the isocyanate group, it is preferable to use a silane coupling agent having an amino group or a mercapto group. Specific examples of preferred silane coupling agents include N-(β-aminoethyl)-γ-aminopropyltrimethoxysilane, N-(β-aminoethyl)-γ-aminopropyltrimethyldimethoxysilane, N-phenyl-γ-aminopropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, γ-aminopropyltrimethoxysilane, and 3-isocyanatetopropyltrimethoxysilane.

[0053] Furthermore, moisture-curable resin (A) may have radical polymerizable functional groups other than moisture-curable urethane resin. Preferred radical polymerizable functional groups are those having a reactive double bond, and (meth)acryloyl groups are particularly preferred from the viewpoint of reactivity. Note that moisture-curable resins having radical polymerizable functional groups other than moisture-curable urethane resin are not included in the radical polymerizable compound (B) described later, and are treated as moisture-curable resins. The moisture-curing resin (A) may be selected from the various resins described above and used alone, or two or more may be used in combination.

[0054] The weight-average molecular weight of the moisture-curing resin (A) is not particularly limited, but is preferably 1,000 to 100,000, more preferably 2,000 to 70,000, and even more preferably 3,000 to 50,000. In this specification, the above weight-average molecular weight is determined by measuring it by gel permeation chromatography (GPC) and converting it to polystyrene equivalent. A Shodex LF-804 (manufactured by Showa Denko Corporation) is an example of a column used when measuring the weight-average molecular weight in polystyrene equivalent by GPC. Tetrahydrofuran is an example of a solvent used in GPC.

[0055] (Radical polymerizable compound (B)) The moisture-curable resin composition preferably further contains a radical polymerizable compound (B). The radical polymerizable compound (B) is not particularly limited as long as it is a radical polymerizable compound having a radical polymerizable functional group in its molecule. The radical polymerizable compound (B) is preferably a compound having an unsaturated double bond as the radical polymerizable functional group, and is particularly preferably a compound having a (meth)acryloyl group (hereinafter also referred to as "(meth)acrylic compound"). In the present invention, by using a (meth)acrylic compound, it becomes easier to adjust the above-mentioned storage modulus and elongation at break to within a predetermined range.

[0056] Examples of (meth)acrylic compounds include (meth)acrylic acid ester compounds, epoxy (meth)acrylates, and urethane (meth)acrylates. Among these, (meth)acrylic acid ester compounds are preferred, and it is also preferable to use (meth)acrylic acid ester compounds and urethane (meth)acrylates in combination. Furthermore, the urethane (meth)acrylate does not contain residual isocyanate groups. Furthermore, in this specification, "(meth)acryloyl group" means acryloyl group or methacryloyl group, and "(meth)acrylate" means acrylate or methacrylate, and the same applies to other similar terms.

[0057] The above (meth)acrylic acid ester compound may be monofunctional, bifunctional, or trifunctional or more, but it is preferably monofunctional. Examples of monofunctional (meth)acrylic acid ester compounds include methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, t-butyl (meth)acrylate, n-pentyl (meth)acrylate, n-hexyl (meth)acrylate, n-octyl (meth)acrylate, isooctyl (meth)acrylate, and 2-ethylhexyl (meth)acrylate. Alkyl(meth)acrylates with approximately 1 to 18 carbon atoms, such as isononyl(meth)acrylate, isodecyl(meth)acrylate, lauryl(meth)acrylate, myristyl(meth)acrylate, tridecyl(meth)acrylate, isomiristyl(meth)acrylate, cetyl(meth)acrylate, stearyl(meth)acrylate, isostearyl(meth)acrylate, cyclohexyl(meth)acrylate, 4-tert-butylcyclohexyl(meth)acrylate, 3,3,Alicyclic (meth)acrylates such as 5-trimethylcyclohexyl (meth)acrylate, isobornyl (meth)acrylate, dicyclopentanyl (meth)acrylate, dicyclopentenyl (meth)acrylate, and 1-adamantyl (meth)acrylate; hydroxyalkyl (meth)acrylates such as 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, and 4-hydroxybutyl (meth)acrylate; and alkoxyalkyl (meth)acrylates such as 2-methoxyethyl (meth)acrylate, 2-ethoxyethyl (meth)acrylate, and 2-butoxyethyl (meth)acrylate. Examples include alkoxyethylene glycol (meth)acrylates such as methyl(meth)acrylate, methoxyethylene glycol (meth)acrylate, and ethoxyethylene glycol (meth)acrylate; polyoxyethylene-based (meth)acrylates such as methoxydiethylene glycol (meth)acrylate, methoxytriethylene glycol (meth)acrylate, methoxypolyethylene glycol (meth)acrylate, ethyl carbitol (meth)acrylate, ethoxydiethylene glycol (meth)acrylate, ethoxytriethylene glycol (meth)acrylate, and ethoxypolyethylene glycol (meth)acrylate.

[0058] Furthermore, the (meth)acrylic acid ester compound may have an aromatic ring, for example, benzyl (meth)acrylate, phenylalkyl (meth)acrylate such as 2-phenylethyl (meth)acrylate, and phenoxyalkyl (meth)acrylate such as phenoxyethyl (meth)acrylate. Moreover, it may be a (meth)acrylate having multiple benzene rings such as a fluorene skeleton or a biphenyl skeleton, specifically, fluorene-type (meth)acrylate and ethoxylated o-phenylphenol acrylate. Furthermore, other examples include phenoxypolyoxyethylene-based (meth)acrylates such as phenoxydiethylene glycol (meth)acrylate, phenoxypolyethylene glycol (meth)acrylate, nonylphenoxydiethylene glycol (meth)acrylate, and nonylphenoxypolyethylene glycol (meth)acrylate.

[0059] Furthermore, monofunctional (meth)acrylic acid ester compounds include heterocyclic (meth)acrylates such as tetrahydrofurfuryl (meth)acrylate, alkoxylated tetrahydrofurfuryl (meth)acrylate, cyclic trimethylolpropaneformal (meth)acrylate, and 3-ethyl-3-oxetanylmethyl (meth)acrylate, as well as phthalimide acrylates such as N-acryloyloxyethylhexahydrophthalimide, various imide (meth)acrylates, and 2,2,2-trifluoroethyl (meth)acrylate. Other examples include phosphates, 2,2,3,3-tetrafluoropropyl (meth)acrylate, 1H,1H,5H-octafluoropentyl (meth)acrylate, dimethylaminoethyl (meth)acrylate, diethylaminoethyl (meth)acrylate, 2-(meth)acryloyloxyethyl succinic acid, 2-(meth)acryloyloxyethyl hexahydrophthalic acid, 2-(meth)acryloyloxyethyl-2-hydroxypropyl phthalate, glycidyl (meth)acrylate, 2-(meth)acryloyloxyethyl phosphate, etc.

[0060] Examples of bifunctional (meth)acrylic acid ester compounds include 1,3-butanediol di(meth)acrylate, 1,4-butanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, 1,9-nonanediol di(meth)acrylate, 1,10-decanediol di(meth)acrylate, 2-n-butyl-2-ethyl-1,3-propanediol di(meth)acrylate, ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, tetraethylene glycol di(meth)acrylate, polyethylene glycol di(meth)acrylate, dipropylene glycol di(meth)acrylate, tripropylene glycol di(meth)acrylate, polypropylene glycol di(meth)acrylate. Examples include meth)acrylate, ethylene oxide-added bisphenol A di(meth)acrylate, propylene oxide-added bisphenol A di(meth)acrylate, ethylene oxide-added bisphenol F di(meth)acrylate, dimethylol dicyclopentadienyl di(meth)acrylate, neopentyl glycol di(meth)acrylate, ethylene oxide-modified isocyanurate di(meth)acrylate, 2-hydroxy-3-(meth)acryloyloxypropyl(meth)acrylate, carbonate diol di(meth)acrylate, polyether diol di(meth)acrylate, polyester diol di(meth)acrylate, polycaprolactone diol di(meth)acrylate, and polybutadiene diol di(meth)acrylate.

[0061] Furthermore, examples of (meth)acrylic acid ester compounds with three or more functionalities include trimethylolpropane tri(meth)acrylate, ethylene oxide-added trimethylolpropane tri(meth)acrylate, propylene oxide-added trimethylolpropane tri(meth)acrylate, caprolactone-modified trimethylolpropane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, ethylene oxide-added isocyanuric acid tri(meth)acrylate, glycerin tri(meth)acrylate, propylene oxide-added glycerin tri(meth)acrylate, tris(meth)acryloyloxyethyl phosphate, ditrimethylolpropane tetra(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol penta(meth)acrylate, and dipentaerythritol hexa(meth)acrylate.

[0062] Examples of the epoxy (meth)acrylates mentioned above include those obtained by reacting an epoxy compound with (meth)acrylic acid. The reaction between the epoxy compound and (meth)acrylic acid should be carried out according to conventional methods, such as in the presence of a basic catalyst. The epoxy (meth)acrylate may be monofunctional or polyfunctional (e.g., difunctional). Examples of epoxy compounds that serve as raw materials for synthesizing the above epoxy (meth)acrylates include bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, 2,2'-diallylbisphenol A type epoxy resin, hydrogenated bisphenol type epoxy resin, propylene oxide-added bisphenol A type epoxy resin, resorcinol type epoxy resin, biphenyl type epoxy resin, sulfide type epoxy resin, diphenyl ether type epoxy resin, dicyclopentadiene type epoxy resin, naphthalene type epoxy resin, phenol novolac type epoxy resin, orthocresol novolac type epoxy resin, dicyclopentadiene novolac type epoxy resin, biphenyl novolac type epoxy resin, naphthalenephenol novolac type epoxy resin, glycidylamine type epoxy resin, alkyl polyol type epoxy resin, rubber-modified epoxy resin, glycidyl ester compounds, bisphenol A type episulfide resin, and the like.

[0063] Examples of commercially available epoxy (meth)acrylates include EBECRYL860, EBECRYL3200, EBECRYL3201, EBECRYL3412, EBECRYL3600, EBECRYL3700, EBECRYL3701, EBECRYL3702, EBECRYL3703, EBECRYL3800, EBECRYL6040, and EBECRYL Examples include RDX63182 (all manufactured by Daicel Ornex Co., Ltd.), EA-1010, EA-1020, EA-5323, EA-5520, EACHD, EMA-1020 (all manufactured by Shin Nakamura Chemical Industry Co., Ltd.), epoxy ester M-600A, epoxy ester 40EM, epoxy ester 70PA, epoxy ester 200PA, epoxy ester 80MFA, epoxy ester 3002M, epoxy ester 3002A, epoxy ester 1600A, epoxy ester 3000M, epoxy ester 3000A, epoxy ester 200EA, epoxy ester 400EA (all manufactured by Kyoeisha Chemical Co., Ltd.), Denacol acrylate DA-141, Denacol acrylate DA-314, Denacol acrylate DA-911 (all manufactured by Nagase ChemteX Co., Ltd.), etc.

[0064] For example, urethane (meth)acrylate can be obtained by reacting an isocyanate compound with a (meth)acrylic acid derivative having a hydroxyl group. Here, a catalytic amount of a tin-based compound or the like is preferable as a catalyst for the reaction between the isocyanate compound and the (meth)acrylic acid derivative. The urethane (meth)acrylate may be monofunctional or polyfunctional, such as difunctional.

[0065] Examples of isocyanate compounds used to obtain urethane (meth)acrylates include polyisocyanate compounds such as isophorone diisocyanate, 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, hexamethylene diisocyanate, trimethylhexamethylene diisocyanate, diphenylmethane-4,4'-diisocyanate (MDI), hydrogenated MDI, polymeric MDI, 1,5-naphthalene diisocyanate, norbornane diisocyanate, tollidine diisocyanate, xylylene diisocyanate (XDI), hydrogenated XDI, lysine diisocyanate, triphenylmethane triisocyanate, tris(isocyanatephenyl)thiophosphate, tetramethylxylylene diisocyanate, and 1,6,11-undecane triisocyanate.

[0066] Furthermore, as the isocyanate compound, a chain-extended polyisocyanate compound obtained by the reaction of a polyol with an excess isocyanate compound can also be used. Examples of polyols include ethylene glycol, propylene glycol, glycerin, sorbitol, trimethylolpropane, carbonate diol, polyether diol, polyester diol, and polycaprolactone diol.

[0067] Furthermore, to obtain monofunctional urethane (meth)acrylates as isocyanate compounds, for example, monoisocyanates can be used. Specific examples of monoisocyanates include alkane monoisocyanates such as butane isocyanate, hexane isocyanate, and decane isocyanate, and aliphatic monoisocyanates such as cyclopentane isocyanate, cyclohexane isocyanate, and isophorone monoisocyanate. The isocyanate compound used to obtain urethane (meth)acrylate may be used alone or in combination of two or more types.

[0068] Examples of (meth)acrylic acid derivatives having the above-mentioned hydroxyl group include mono(meth)acrylates of dihydric alcohols such as ethylene glycol, propylene glycol, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, and polyethylene glycol; mono(meth)acrylates or di(meth)acrylates of trihydric alcohols such as trimethylolethane, trimethylolpropane, and glycerin; and epoxy(meth)acrylates such as bisphenol A type epoxy(meth)acrylate. The (meth)acrylic acid derivative used to obtain urethane (meth)acrylate may be used alone or in combination of two or more types.

[0069] Polyfunctional urethane (meth)acrylates can be obtained by reacting a polyisocyanate compound with a (meth)acrylic acid derivative having a hydroxyl group. Furthermore, monofunctional urethane (meth)acrylates can be obtained by reacting a monoisocyanate compound with a (meth)acrylic acid derivative having a hydroxyl group. However, urethane (meth)acrylates obtained by reacting a monoisocyanate compound with a dihydric alcohol mono(meth)acrylate are preferred, and a preferred specific example is 1,2-ethanediol 1-acrylate 2-(N-butylcarbamate).

[0070] Commercially available urethane (meth)acrylates include, for example, M-1100, M-1200, M-1210, M-1600 (all manufactured by Toagosei Co., Ltd.), EBECRYL230, EBECRYL270, EBECRYL8402, EBECRYL8411, EBECRYL8412, EBECRYL8413, EBECRYL8804, EBECRYL8803, EBECRYL8807, EBECRYL9270, E BECRYL210, EBECRYL4827, EBECRYL6700, EBECRYL220, EBECRYL2220 (all manufactured by Daicel Ornex Co., Ltd.), Art Resin UN-9000H, Art Resin UN-9000A, Art Resin UN-7100, Art Resin UN-1255, Art Resin UN-330, Art Resin UN-3320HB, Art Resin UN-1200TPK, Art Resin SH-500B (all) Manufactured by Negami Kogyo), U-2HA, U-2PHA, U-3HA, U-4HA, U-6H, U-6LPA, U-6HA, U-10H, U-15HA, U-122A, U-122P, U-108, U-108A, U-324A , U-340A, U-340P, U-1084A, U-2061BA, UA-340P, UA-4100, UA-4000, UA-4200, UA-4400, UA-5201P, UA-7100, UA-7200, U Examples include A-W2A (all manufactured by Shin Nakamura Chemical Industry Co., Ltd.), AI-600, AH-600, AT-600, UA-101I, UA-101T, UA-306H, UA-306I, UA-306T (all manufactured by Kyoeisha Chemical Co., Ltd.), CN-902, CN-973, CN-9021, CN-9782, CN-9833 (all manufactured by Arkema), Viscoat #216 (manufactured by Osaka Organic Chemical Industry Co., Ltd.), and GENOMER 1122 (manufactured by Rahn). The (meth)acrylic compounds described above may be used individually or in combination of two or more.

[0071] Furthermore, as the radical polymerizable compound (B), (meth)acrylic compounds or vinyl compounds other than the (meth)acrylic acid ester compounds described above may be used in combination. Such compounds include (meth)acrylic compounds having a cyclic structure such as (meth)acryloylmorpholine, and vinyl compounds having a cyclic structure such as N-vinyl-2-pyrrolidone and N-vinyl-ε-caprolactam. In addition, (meth)acrylamide compounds such as N,N-dimethyl(meth)acrylamide, N-hydroxyethyl(meth)acrylamide, N,N-diethyl(meth)acrylamide, N-isopropyl(meth)acrylamide, and N,N-dimethylaminopropyl(meth)acrylamide can also be used.

[0072] As the radical polymerizable compound (B), from the viewpoint of easily increasing shear adhesive strength, it is preferable to use at least one selected from urethane (meth)acrylate and alkyl (meth)acrylate among the above, and these may be used in combination, but it is more preferable to use at least alkyl (meth)acrylate. The urethane (meth)acrylate is not particularly limited, but is contained in an amount of, for example, 1 to 30 parts by mass, preferably 5 to 25 parts by mass, per 100 parts by mass of the total amount of the moisture-curable resin (A) and the radical polymerizable compound (B). Furthermore, the alkyl (meth)acrylate is not particularly limited, but is contained in an amount of, for example, 5 to 40 parts by mass, preferably 10 to 30 parts by mass, based on 100 parts by mass of the total amount of the moisture-curable resin (A) and the radical polymerizable compound (B).

[0073] In the present invention, the radical polymerizable compound (B) is appropriately selected and adjusted so that the cured product does not have a glass transition temperature within a temperature range of 10°C or higher. For example, the radical polymerizable compound (B) preferably contains a compound with a low glass transition temperature (Tg) when it is formed as a homopolymer (a low-Tg compound, for example, a compound whose Tg is less than 0°C, preferably -10°C or lower, more preferably -20°C or lower, and even more preferably -30°C or lower). Furthermore, it is also preferable to use, in addition to the low-Tg compound, a compound with a high glass transition temperature (Tg) when formed as a homopolymer (high-Tg compound, where the Tg is, for example, 0°C or higher, preferably 10°C or higher, more preferably 20°C or higher) to such an extent that the cured product does not have a glass transition temperature within a temperature range of 10°C or higher. Using a high-Tg compound tends to improve shear adhesion strength.

[0074] Examples of low Tg compounds include alkyl acrylates such as butyl acrylate (Tg=-55°C), octyl acrylate (Tg=-65°C), isooctyl acrylate (Tg=-55°C), 2-ethylhexyl acrylate (Tg=-70°C), isononyl acrylate (Tg=-55°C), isodecyl acrylate (Tg=-60°C), lauryl acrylate (Tg=-30°C), and tridecyl acrylate (Tg=-55°C). These may be used individually or in combination of two or more. Furthermore, as the radical polymerizable compound (B), it is preferable to use an alkyl (meth)acrylate such as stearyl acrylate (Tg=35°C) as a high Tg compound, but alicyclic structure-containing (meth)acrylic compounds such as isobornyl acrylate (Tg=88°C) or amide group-containing vinyl monomers such as N-acryloyloxyethyl hexahydrophthalimide (Tg=56°C) may also be used. These may be used individually or in combination of two or more. The Tg values ​​in parentheses for each of the above compounds represent the glass transition temperature when the compound is a homopolymer. Furthermore, the radical polymerizable compound (B) may also preferably contain urethane (meth)acrylate as described above. The urethane (meth)acrylate may be monofunctional or polyfunctional, but it is preferable that it contains at least monofunctional material. Using monofunctional urethane (meth)acrylate makes it easier to increase the shear bond strength. In addition, the urethane (meth)acrylate may be the low-Tg compound or the high-Tg compound described above.

[0075] (Resin component content) The content of moisture-curable resin (A) in the moisture-curable resin composition may be, for example, 50 parts by mass or more, but preferably 60 parts by mass or more, based on 100 parts by mass of the total amount of moisture-curable resin (A) and radical polymerizable compound (B). A content of 60 parts by mass or more tends to increase the elongation at break, making it easier to improve impact resistance. Furthermore, the content of the moisture-curable resin (A) may be 100 parts by mass or less, but is preferably 80 parts by mass or less, more preferably 75 parts by mass or less, and even more preferably 70 parts by mass or less. By limiting the content of the moisture-curable resin (A) to 80 parts by mass or less, the content of the radical polymerizable compound (B) becomes above a certain amount, which lowers the viscosity and improves the coatability. In addition, the shape retention after coating tends to be good. On the other hand, the content of the radical polymerizable compound (B) may be, for example, 50 parts by mass or less, but preferably 40 parts by mass or less, based on 100 parts by mass of the total amount of the moisture-curable resin (A) and the radical polymerizable compound (B). Furthermore, the radical polymerizable compound (B) does not have to be contained in the moisture-curable resin composition, and therefore, the above content of the radical polymerizable compound (B) may be 0 parts by mass or more, but preferably 20 parts by mass or more, more preferably 25 parts by mass or more, and even more preferably 30 parts by mass or more.

[0076] The total amount of moisture-curable resin (A) and radical polymerizable compound (B) is, for example, 60% by mass or more, preferably 70% by mass or more, more preferably 75% by mass or more, based on the total amount of the moisture-curable resin composition, and may be 100% by mass or less, but is preferably 99% by mass or less, and even more preferably 97% by mass or less, in order to include other components such as photopolymerization initiators. Note that the total amount of the moisture-curable resin composition is based on the total amount of solids contained in the moisture-curable resin composition. For example, if the moisture-curable resin composition contains a solvent to dilute the composition, the amount of components excluding the solvent will be the total amount of the moisture-curable resin composition.

[0077] (Crosslinking agent (X)) The moisture-curable resin composition of the present invention may contain a crosslinking agent (X). The inclusion of a crosslinking agent (X) enhances the elongation at break and storage modulus, thereby improving adhesive performance and impact resistance. The crosslinking agent (X) is preferably a compound having a functional group that can react with at least one of the above-mentioned moisture-curable resin (A) and radical polymerizable compound (B) when the moisture-curable resin composition cures. Specifically, a compound having an isocyanate group is an example. Such a compound is a polyisocyanate compound having two or more isocyanate groups in one molecule. Furthermore, the crosslinking agent (X) is preferably included in the moisture-curable resin composition when the moisture-curable resin composition contains a radical polymerizable compound (B).

[0078] Examples of polyisocyanate compounds used as crosslinking agents (X) include aromatic polyisocyanate compounds and aliphatic polyisocyanate compounds. Examples of aromatic polyisocyanate compounds include diphenylmethane diisocyanate, liquid modified diphenylmethane diisocyanate, polymeric MDI, tolylene diisocyanate, and naphthalene-1,5-diisocyanate. Examples of aliphatic polyisocyanate compounds include hexamethylene diisocyanate, trimethylhexamethylene diisocyanate, lysine diisocyanate, norbornane diisocyanate, transcyclohexane-1,4-diisocyanate, isophorone diisocyanate, hydrogenated xylylene diisocyanate, hydrogenated diphenylmethane diisocyanate, cyclohexane diisocyanate, bis(isocyanate-methyl)cyclohexane, and dicyclohexylmethane diisocyanate. As for the polyisocyanate compound, aromatic polyisocyanate compounds are preferred from the viewpoint of increasing the storage modulus and improving adhesive performance, diphenylmethane diisocyanate and its modified products and polymeric MDI are more preferred, and diphenylmethane diisocyanate is even more preferred. Polyisocyanate compounds may be used individually or in combination of two or more.

[0079] The crosslinking agent (X) content in the moisture-curable resin composition is preferably 0.4 parts by mass or more and 10 parts by mass or less per 100 parts by mass of the total amount of moisture-curable resin (A) and radical polymerizable compound (B). By setting the crosslinking agent (X) content to 0.4 parts by mass or more, even when using radical polymerizable compound (B), it becomes easier to achieve a fracture elongation of a predetermined value or higher, and it also becomes easier to improve adhesive strength and other properties. On the other hand, by setting it to 10 parts by mass or less, it is possible to ensure a certain amount or more of moisture-curable resin (A) and radical polymerizable compound (B), making it easier to increase fracture elongation and other properties, and resulting in superior impact resistance. From the above viewpoint, the crosslinking agent content is more preferably 0.8 parts by mass or more, even more preferably 1.0 part by mass or more, even more preferably 6 parts by mass or less, and even more preferably 5 parts by mass or less.

[0080] (Photopolymerization initiator (Y)) When using the above-mentioned radical polymerizable compound (B), the moisture-curable resin composition of the present invention preferably contains a photopolymerization initiator (Y) in order to ensure photocurability. Examples of photopolymerization initiators (Y) include photoradical polymerization initiators. Specifically, these include benzophenone compounds, acetophenone compounds such as α-aminoalkylphenone and α-hydroxyalkylphenone, acylphosphine oxide compounds, titanocene compounds, oxime ester compounds, benzoin ether compounds, and thioxanthones. Among these, acetophenone compounds are preferred, and α-aminoalkylphenone is more preferred, from the viewpoint of easily adjusting the elongation at break and storage modulus within a predetermined range. Examples of commercially available photopolymerization initiators include IRGACURE184, IRGACURE369, IRGACURE379, IRGACURE379EG, IRGACURE651, IRGACURE784, IRGACURE819, IRGACURE907, IRGACURE2959, IRGACURE OXE01, and Lucilin TPO (all manufactured by BASF), as well as benzoin methyl ether, benzoin ethyl ether, and benzoin isopropyl ether (all manufactured by Tokyo Chemical Industry Co., Ltd.).

[0081] The content of the photopolymerization initiator (Y) in the moisture-curable resin composition is preferably 0.01 parts by mass to 10 parts by mass, more preferably 0.5 parts by mass to 5 parts by mass, per 100 parts by mass of the radical polymerizable compound. By having the photopolymerization initiator (Y) content within this range, the resulting moisture-curable resin composition exhibits excellent photocurability and storage stability. Furthermore, within this range, the radical polymerizable compound (B) is moderately cured, making it easier to adjust the shear adhesion strength, elongation at break, and other properties to within a predetermined range.

[0082] (Filler) The moisture-curing resin composition of the present invention may contain a filler. By including a filler, the moisture-curing resin composition of the present invention will have suitable thixotropy and will be able to sufficiently maintain its shape after application. Particulate fillers may be used. Inorganic fillers are preferred as fillers, such as silica, talc, titanium dioxide, zinc oxide, and calcium carbonate. Among these, silica is preferred because the resulting moisture-curable resin composition has excellent ultraviolet transmittance. The fillers may also be subjected to hydrophobic surface treatments such as silylation, alkylation, or epoxidation. The filler may be used alone or in combination of two or more types. The filler content is, for example, 1 to 30 parts by mass, preferably 2 to 25 parts by mass, and more preferably 5 to 15 parts by mass, based on 100 parts by mass of the total amount of moisture-curable resin (A) and radical polymerizable compound (B). A filler content of 1 part by mass or more makes it easier to maintain the shape well after application. Furthermore, a filler content of 30 parts by mass or less makes it easier to adjust the viscosity within an appropriate range, resulting in good coatability.

[0083] (Coupling agent) The moisture-curing resin composition may contain a coupling agent. The inclusion of a coupling agent makes it easier to improve adhesion. Examples of coupling agents include silane coupling agents, titanate coupling agents, and zirconate coupling agents. Among these, silane coupling agents are preferred due to their excellent effect in improving adhesion. The above coupling agents may be used individually or in combination of two or more types. The coupling agent content is preferably 0.05 parts by mass to 5 parts by mass, more preferably 0.2 parts by mass to 2 parts by mass, and even more preferably 0.5 parts by mass to 1.5 parts by mass, based on 100 parts by mass of the total amount of moisture-curable resin (A) and radical polymerizable compound (B). By keeping the coupling agent content within these ranges, the adhesive strength can be improved without significantly affecting other physical properties.

[0084] The moisture-curable resin composition of the present invention may be diluted with a solvent as needed. When the moisture-curable resin composition is diluted with a solvent, the parts by mass of the moisture-curable resin composition are based on the solids content, that is, the parts by mass excluding the solvent. Furthermore, the moisture-curing resin composition may also contain additives other than those mentioned above, such as wax particles, metal-containing particles, light-shielding agents, colorants, reactive diluents, and moisture-curing accelerating catalysts.

[0085] A method for producing a moisture-curable resin composition involves mixing the components of the composition using a mixer. For example, this method involves mixing a moisture-curable resin (A), a radical polymerizable compound (B), and, if necessary, a crosslinking agent (X), a photopolymerization initiator (Y), a filler, a coupling agent, and other additives. Examples of mixers include homodispers, homomixers, universal mixers, planetary mixers, kneaders, and three-roll mixers.

[0086] [Method of using moisture-curing resin composition] The moisture-curable resin composition of the present invention is cured and used as a cured product. If the moisture-curable resin composition of the present invention is photocurable, thermocurable, or both, it is preferable to first cure it by photocuring, thermocuring, or both by light irradiation or heating to reach, for example, a B-stage state (partially cured state), and then further cure it with moisture to achieve full curing. The moisture-curable resin composition of the present invention is preferably photo-moisture-curable. Therefore, it is preferable to cure it by light irradiation to reach a B-stage state (partially cured state), and then further cure it with moisture to achieve full curing.

[0087] Here, when the moisture-curing resin composition is placed between adherends to join them, it is preferable to apply it to one adherend, then cure it by light irradiation or other means to reach a B-stage state, for example, and then place the other adherend on top of the moisture-curing resin composition that has hardened to the B-stage state, thereby temporarily bonding the adherends together with an appropriate adhesive force (initial adhesive force). Subsequently, the moisture-curing resin composition in the B-stage state is cured by moisture to fully harden, and the adherends that have been placed together are joined with sufficient adhesive force via the moisture-curing resin composition.

[0088] Here, the light irradiated during photocuring is not particularly limited as long as it is light that cures the radical polymerizable compound (B), but ultraviolet light is preferred. Furthermore, when heat curing, the temperature is not particularly limited as long as it is the temperature at which the thermosetting resin cures, but for example, it is preferable to heat it to a temperature of 60°C or higher but less than 120°C, more preferably less than 100°C. In addition, when curing the moisture-curable resin composition by moisture, it is sufficient to leave it in the atmosphere for a predetermined time.

[0089] Furthermore, it is preferable to apply the moisture-curable resin composition to the substrate using a dispenser. Examples of dispensers include air dispensers, jet dispensers, monopump dispensers, screw dispensers, and handgun dispensers, but among these, jet dispensers are preferred. In the present invention, by keeping the viscosity within the predetermined range as described above, it is possible to apply the moisture-curable resin composition by jet dispenser in a fine wire shape, for example, 1 mm or less, preferably about 0.1 to 0.7 mm, with good applicability. In addition, with a jet dispenser, for example, the moisture-curable resin composition can be heated to about 70 to 100°C before application.

[0090] The moisture-curable resin composition of the present invention is preferably used as an adhesive for electronic devices. More preferably, it is used as an adhesive for portable electronic devices. More specifically, portable electronic devices include mobile phones such as smartphones and tablet devices. When these portable electronic devices are accidentally dropped during use, the components to which the adhesive is applied may detach. However, when the moisture-curable resin composition of the present invention is used as an adhesive for portable electronic devices, the cured product of the moisture-curable resin composition of the present invention has excellent impact resistance, making it difficult for the adhesive to detach. In electronic devices, the adherend is not particularly limited, but can be, for example, various components that make up the electronic device. Examples of various components that make up the electronic device include electronic components, or substrates on which electronic components are attached, and more specifically, various electronic components provided on display elements, substrates on which electronic components are attached, semiconductor chips, etc. In other words, the present invention also provides electronic components that include a cured product of a moisture-curable resin composition. The material of the adherend can be any of the following: metal, glass, plastic, etc. The shape of the adherend is not particularly limited and can be, for example, film, sheet, plate, panel, tray, rod, box, or housing.

[0091] The moisture-curable resin composition of the present invention exhibits excellent impact resistance because the cured product of the moisture-curable resin composition has shear adhesive strength and elongation at break that are above predetermined values, while not having a glass transition temperature in a temperature range of 10°C or higher. Therefore, even when the coating width or bonding area of ​​the moisture-curable resin composition of the present invention is small, the adherend will not peel off, for example, when a large impact is applied to the adherend. Therefore, it is suitable for use as an adhesive for joining semiconductor chips with small bonding areas, and as an adhesive for display devices, such as display devices for portable electronic devices, particularly for mobile phones such as smartphones, where the application width tends to be small. [Examples]

[0092] The present invention will be described in more detail by reference to examples, but the present invention is not limited in any way by these examples.

[0093] In this embodiment, various physical properties were measured and performance was evaluated as follows. (Shear bond strength) Adhesion test samples were prepared from the moisture-curable resin compositions obtained in each example and comparative example according to the method described in the specification. The adhesive strength of the prepared adhesion test samples was measured at 25°C using the method described in the specification.

[0094] (Storage modulus) Cured samples were prepared from moisture-curable resin compositions according to the method described in the specification, and the storage modulus of the cured samples at 25°C was measured using a dynamic viscoelasticity measuring device (manufactured by IT Measurement Control Co., Ltd., product name "DVA-200"). The measurement conditions were tensile deformation mode, set strain of 1%, measurement frequency of 1 Hz, and heating rate of 5°C / min.

[0095] (Elongation at break) Test specimens were prepared from the moisture-curing resin composition according to the method described in the specification. They were then pulled at a speed of 50 mm / min until fracture using a tensile testing machine (manufactured by A&D Company, Limited, trade name "TENSILON"), and the elongation at fracture at 25°C was measured.

[0096] (viscosity) The moisture-curing resin compositions obtained in each example and comparative example were subjected to a cone-plate viscometer (Toki Sangyo Co., Ltd., "VISCOMETER TV-22", cone rotor "3 o The viscosity was measured at 80°C under the conditions of a rotation speed of 20 rpm using ×R7.7.

[0097] (Glass transition temperature) Each cured product obtained from the moisture-curable resin compositions in each example and comparative example was cured using the method described in the specification, and cut into pieces with a width of 3 mm, a length of 20 mm, and a thickness of 0.8 mm. The dynamic viscoelasticity of the cut cured products was measured in the range of -100°C to 100°C using a dynamic viscoelasticity measuring device (IT Measurement Control Co., Ltd., "DVA-200") under the conditions of deformation mode: tension, set strain of 1%, measurement frequency of 1 Hz, and heating rate of 5°C / min, and the temperature at which the loss tangent (tanδ) was maximized was determined as the glass transition point.

[0098] (Impact resistance test) Figure 2 shows an overview of the impact resistance adhesion test. As shown in Figure 2(a), a 2mm thick polycarbonate plate 3 was prepared with a rectangular hole 2 measuring 38mm x 50mm in the center. The outer dimensions were 46mm x 61mm and the inner dimensions were 44mm x 59mm. Moisture-curing resin composition 1 was applied to the polycarbonate plate 3 in a rectangular frame shape with a coating width of 1mm, surrounding the rectangular hole 2. Using a UV-LED (wavelength 365nm), ultraviolet light was applied at 1000mJ / cm² in an environment of 25°C and 50%RH. 2 The moisture-curing resin composition 1 was photocured by irradiation. Subsequently, a polycarbonate sheet 4 measuring 50 mm x 75 mm and 4 mm thick was attached to a polycarbonate sheet 3 via the semi-cured moisture-curing resin composition 1 to assemble the test specimen. The polycarbonate sheet 4 and the rectangular frame-shaped moisture-curing resin composition 1 were aligned at their central positions. Subsequently, the polycarbonate sheet 3 was inverted from the state shown in Figure 2(a) and positioned so that it rested on top of the polycarbonate sheet 4. With a pressure of 5 kgf applied from the polycarbonate sheet 3 side, the moisture-curing resin composition 1 was left at room temperature (23°C) and 50% RH for 24 hours to allow it to moisture-cur, and the polycarbonate sheet 4 and the polycarbonate sheet 3 were bonded together with the fully cured moisture-curing resin composition 1. Next, as shown in Figure 2(b), the fabricated test specimen was fixed to the support base 5, and a 300g iron ball 6, sized to pass through the rectangular hole 2, was dropped from a height of 20mm so that it would pass through the rectangular hole 2. The iron ball was dropped repeatedly under the same conditions, and the impact resistance was determined according to the following evaluation criteria. AA: Even after dropping the steel ball 80 times, the polycarbonate sheet did not peel off. A: The polycarbonate sheet peeled off after dropping the steel ball 40 to less than 80 times. B: The polycarbonate sheet peeled off after dropping the steel ball 20 to less than 40 times. B: The polycarbonate sheet peeled off after dropping the steel ball less than 20 times.

[0099] (Evaluation of fine wire coating properties) Using a jet dispenser ("PICO Pulse," manufactured by Nordson), the moisture-curing resin composition was heated to 80°C and applied to an aluminum substrate to a width of 0.5 mm and a length of 25 ± 2 mm. The condition during and after application was observed and evaluated according to the following evaluation criteria. A: The coating was applied uniformly with no variation in line width, resulting in good coating performance. B: Although some variation occurred in line width, the moisture-curing composition could be applied without any practical problems. C: The water-curing composition could not be completely dispensed from the jet dispenser, resulting in practical application problems.

[0100] (Shape retention evaluation) Furthermore, in the evaluation of the fine-line coating properties described above, the moisture-curing resin composition coated on the substrate was subjected to 365nm ultraviolet light from an LED lamp at 1000mJ / cm² under conditions of 25°C and 50%RH, 5 seconds after the completion of coating. 2 The material was irradiated. Next, after being left for 16 hours in an environment of 25°C and 50% RH, the width (maximum width) and height (maximum height) of the cured material were measured using a laser microscope (product name "VK-X200", manufactured by Keyence Corporation). The ratio of the height to the width of the cured material was calculated as the aspect ratio. The shape retention was evaluated based on the calculated aspect ratio according to the following evaluation criteria. A: Aspect ratio of 0.4 or higher B: Aspect ratio less than 0.4

[0101] The components used in the examples and comparative examples were as follows: (Moisture-curing resin (A)) Moisture-curing urethane resin 1 (PTMG) was prepared according to the following synthesis example 1. [Synthesis Example 1] 100 parts by mass of polytetramethylene ether glycol (manufactured by Mitsubishi Chemical Corporation, trade name "PTMG-2000", average molecular weight 2000) and 0.01 parts by mass of dibutyltin dilaurate were placed in a 500 mL separable flask and stirred under vacuum (20 mmHg or less) at 100 °C for 30 minutes to mix. Then, under atmospheric pressure, 26.5 parts by mass of diphenylmethane diisocyanate (manufactured by Nisso Shoji Co., Ltd., trade name "Pure MDI") was added as the polyisocyanate compound, and the mixture was stirred at 80 °C for 3 hours to obtain moisture-curable urethane resin 1 (weight-average molecular weight 2700).

[0102] Moisture-curing urethane resin 2 (PTMG) was prepared according to the following synthesis example 2. [Synthesis Example 2] 100 parts by mass of polytetramethylene ether glycol (Mitsubishi Chemical Corporation, "PTMG-3000", average molecular weight 3000) as the polyol compound and 0.01 parts by mass of dibutyltin dilaurate were placed in a 500 mL separable flask and stirred under vacuum (20 mmHg or less) at 100°C for 30 minutes to mix. Then, under atmospheric pressure, 17.5 parts by mass of diphenylmethane diisocyanate (Nisso Shoji Co., Ltd., "Pure MDI") as the polyisocyanate compound were added and stirred at 80°C for 3 hours to react and obtain moisture-curable urethane resin 2 (weight-average molecular weight 3500).

[0103] Moisture-curing urethane resin 3 (PPG) was prepared according to the following synthesis example 3. [Synthesis Example 3] 100 parts by mass of polypropylene glycol (Asahi Glass Co., Ltd., "EXCENOL 2020", average molecular weight 2000) as the polyol compound and 0.01 parts by mass of dibutyltin dilaurate were placed in a 500 mL separable flask and stirred under vacuum (20 mmHg or less) at 100 °C for 30 minutes to mix. Then, under atmospheric pressure, 26.5 parts by mass of diphenylmethane diisocyanate (Nisso Shoji Co., Ltd., "Pure MDI") as the polyisocyanate compound were added and stirred at 80 °C for 3 hours to react, yielding a moisture-curable urethane resin 3 (weight-average molecular weight 2900) having isocyanate groups at both ends.

[0104] The moisture-curing urethane resin 4 (polyester) was prepared according to the following synthesis example 4. [Synthesis Example 4] 100 parts by mass of polyester polyol (Kuraray Polyol P-5010 (manufactured by Kuraray Co., Ltd.), a condensate of adipic acid and 3-methyl-1,5-pentadiol) as the polyol compound and 0.01 parts by mass of dibutyltin dilaurate were placed in a 500 mL separable flask and stirred under vacuum (20 mmHg or less) at 100 °C for 30 minutes to mix. Then, under atmospheric pressure, 10.5 parts by mass of diphenylmethane diisocyanate (manufactured by Nisso Shoji Co., Ltd., trade name "Pure MDI") as the polyisocyanate compound were added and the mixture was stirred at 80 °C for 3 hours to obtain a moisture-curable urethane resin 4 (weight-average molecular weight 5700) having isocyanate groups at both ends.

[0105] The moisture-curing urethane resin 5 (polycarbonate) was prepared according to the following synthesis example 5. [Synthesis Example 5] 100 parts by mass of polycarbonate diol (manufactured by Kuraray, trade name "Kuraraypolyol C-1090") and 0.01 parts by mass of dibutyltin dilaurate were placed in a 500 mL separable flask. The flask was mixed under vacuum (20 mmHg or less) by stirring at 100 °C for 30 minutes. Then, the pressure was reduced to atmospheric pressure, and 50 parts by mass of diphenylmethane diisocyanate (manufactured by Nisso Shoji, trade name "Pure MDI") was added as the polyisocyanate compound. The mixture was reacted by stirring at 80 °C for 3 hours to obtain a PC-framed aromatic-terminated urethane having a polycarbonate (PC) backbone with aromatic isocyanate groups at both ends. The weight-average molecular weight of the obtained PC-framed aromatic-terminated urethane was 6000.

[0106] Furthermore, 100 parts by mass of polycarbonate diol (manufactured by Kuraray Co., Ltd., product name "Kuraraypolyol C-1090") and 0.01 parts by mass of dibutyltin dilaurate were placed in a 500 mL separable flask as polyol compounds. The flask was stirred under vacuum (20 mmHg or less) at 100 °C for 30 minutes to mix. After that, the pressure was reduced to atmospheric pressure, and 115 parts by mass of "Duranate A201H" (product name) manufactured by Asahi Kasei Corporation as an aliphatic polyisocyanate compound was added and the mixture was stirred at 80 °C for 3 hours to react and obtain a PC-skeleton aliphatic-terminated urethane having a polycarbonate (PC) skeleton with aliphatic isocyanate groups at both ends. The weight-average molecular weight of the obtained PC-skeleton aliphatic-terminated urethane was 7000. 35 parts by mass of the obtained PC-skeleton aromatic-terminated urethane and 30 parts by mass of the PC-skeleton aliphatic-terminated urethane were mixed to obtain moisture-curable urethane resin 5.

[0107] The components other than the moisture-curing urethane resin used in the examples and comparative examples were as follows: (Radical polymerizable compound (B)) Urethane acrylate (monofunctional): Rahn, "GENOMER1122", Tg: -3℃ Difunctional Urethane Acrylate: Manufactured by Daicel Ornex, product name "EBECRYL8411", difunctional, weight-average molecular weight 12000, diluted with 20% by mass of isovonyl acrylate (IBOA), urethane acrylate (Tg: -18℃) content 80% by mass Phenoxyethyl acrylate: Manufactured by Kyoeisha Chemical Co., Ltd., product name "Light Acrylate PO-A", monofunctional, Tg: 5℃ Lauryl acrylate: Manufactured by Kyoeisha Chemical Co., Ltd., product name "Light Acrylate LA", monofunctional, Tg -30℃ Isobornyl acrylate: Manufactured by Kyoeisha Chemical Co., Ltd., product name "IB-XA", monofunctional, Tg: 94℃ Tridecyl acrylate: manufactured by Sartomer, product name "SR489D", monofunctional, Tg: -55℃ Stearyl acrylate: Manufactured by Sartomer, product name "SR257", monofunctional, Tg: 35℃ Arronix M-140: Manufactured by Toagosei Co., Ltd., product name "Arronix M-140", N-acryloyloxyethylhexahydrophthalimide

[0108] (Crosslinking agent (X)) Diphenylmethane diisocyanate (Photopolymerization initiator (Y)) 2-Benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butanone-1 (BASF, "IRGACURE369") (Coupling agent) 3-Acryloxypropyltrimethoxysilane: Manufactured by Shin-Etsu Chemical Co., Ltd., product name "KBM-5103" (Filler) Silicone-treated silica: Manufactured by Nippon Aerosil Co., Ltd., product name "RY300"

[0109] [Examples 1-9, Comparative Examples 1-4] According to the formulations listed in Table 1, each material was stirred at 50°C using a planetary agitator (Sinky Co., Ltd., "Awatori Rentaro"), and then uniformly mixed at 50°C using a ceramic three-roll roller to obtain the moisture-curing resin compositions of Examples 1-9 and Comparative Examples 1-4.

[0110] [Table 1] *Note that Table 1 shows all the measured glass transition temperatures.

[0111] As shown in the above examples, by increasing both the shear adhesive strength and elongation at break of the cured product, and by not having a glass transition temperature in the temperature range of 10°C or higher, excellent impact resistance was achieved. In contrast, in Comparative Examples 1, 2, and 4, either the shear adhesive strength or elongation at break of the cured product was not high enough, and therefore the impact resistance was not sufficiently high. In Comparative Example 3, although both the shear adhesive strength and elongation at break of the cured product were high, the presence of a glass transition temperature in the temperature range of 10°C or higher prevented the impact resistance from being sufficiently high. [Explanation of symbols]

[0112] 1.10 Moisture-curing resin compositions 2 rectangular hole 3, 4 Polycarbonate sheet 5 Support stand 6 Iron balls 11 Aluminum substrate 12 glass plates 13. Samples for adhesion testing

Claims

1. A photo-moisture-curable resin composition comprising a moisture-curable resin (A), a radical polymerizable compound (B), and a photopolymerization initiator (Y), The moisture-curing resin (A) is a moisture-curing urethane resin having at least one of a polyester skeleton and a polyether skeleton. The radical polymerizable compound (B) comprises at least one selected from the group consisting of urethane (meth)acrylate and alkyl (meth)acrylate, The photo-moisture-curable resin composition wherein the cured product has a shear adhesive strength of 4 MPa or more, which is the strength at which the aluminum substrate and the glass plate are separated, a fracture elongation of 600% or more, and does not have a glass transition temperature in a temperature range of 10°C or higher.

2. The photo-moisture-curable resin composition according to claim 1, wherein the cured product of the photo-moisture-curable resin composition has a glass transition temperature in a temperature range of -20°C or more and less than 10°C.

3. The photo-moisture-curable resin composition according to claim 1 or 2, wherein the cured product of the photo-moisture-curable resin composition has a glass transition temperature in a temperature range of -45°C or lower.

4. A photo-moisture-curable resin composition according to any one of claims 1 to 3, wherein the viscosity measured at 80°C and 20 rpm is 50 Pa·s or less.

5. The photo-moisture-curable resin composition according to any one of claims 1 to 4, wherein the radical polymerizable compound (B) comprises a compound whose glass transition temperature (Tg) when it is a homopolymer is less than 0°C.

6. The photo-moisture-curable resin composition according to any one of claims 1 to 5, comprising 60 parts by mass or more of the moisture-curable resin (A) with respect to a total of 100 parts by mass of the radical polymerizable compound (B) and the moisture-curable resin (A).

7. The photo-moisture-curing resin composition according to any one of claims 1 to 6, wherein the moisture-curing resin (A) comprises a moisture-curing urethane resin having a polyether skeleton.

8. A photo- and moisture-curable resin composition according to any one of claims 1 to 7, for use in application by a jet dispenser.

9. An adhesive for electronic equipment comprising a photo- and moisture-curable resin composition according to any one of claims 1 to 8.

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