TWI835897B - Curable resin composition and hardened body - Google Patents

Abstract

The curable resin composition of the present invention contains a free radical polymerizable compound. After the curable resin composition is applied by an air dispenser, it is irradiated with 365 nm ultraviolet rays at 1000 mJ/ ^cm2 by an LED lamp. After 16 hours in an environment of 25°C and 50% RH, the ratio of the coating height to the line width becomes 0.6 or more. After the ultraviolet rays at 365 nm are irradiated by an LED lamp at 1000 mJ/ ^cm2 , a load of 0.03 MPa is applied, and the thickness variation rate of the curable resin composition before and after the load is less than 40%.

Description

Curable resin composition and hardened body

The present invention relates to a curable resin composition and its cured product. For example, it relates to a curable resin composition used as an adhesive for electronic devices and its cured product.

In recent years, there has been a demand for high integration and miniaturization of electronic parts such as semiconductor chips. For example, there is a situation where a plurality of thin semiconductor chips are bonded together via an adhesive layer to form a laminate of semiconductor chips. In addition, in the modern era where various portable devices with display components such as mobile phones and portable game consoles are popular, it is required to miniaturize the display components. As a method of miniaturizing the display components, the image display portion is narrowed (hereinafter also referred to as "narrow edge design"). In the lamination or narrow edge design of small semiconductor chips, a technology for bonding is required by using an adhesive with a finer line width using a dispenser or the like.

A laminate of semiconductor wafers is produced, for example, by applying an adhesive to one semiconductor wafer, semi-hardening it by irradiating it with light, laminating another semiconductor wafer through the semi-hardened product, and placing the semiconductor wafers between them. The adhesive is temporarily adhered, and then the adhesive is completely hardened to join the wafers. Similarly, for narrow edge designs, methods of semi-hardening and then completely hardening the applied adhesive are also being studied. We are studying the use of light moisture curable resin compositions as adhesives for lamination of semiconductor wafers and narrow edge designs.

As a light moisture curable resin composition used as an adhesive, for example, as disclosed in Patent Document 1, a radical curable urethane resin composition containing a radical polymerizable unsaturated group, a moisture curable urethane prepolymer, and a thixotropic agent is known (for example, refer to Patent Document 1). Patent Document 1 indicates that by making the resin composition contain a predetermined amount of thixotropic agent, the adhesion with the substrate becomes good, and the resin collapse is also prevented. Prior Art Documents Patent Documents

Patent document 1: Japanese Patent Application Publication No. 2004-18621

[Problem to be solved by the invention]

However, for example, when a conventional light moisture curable resin composition is used as an adhesive for a casing of a mobile phone or the like, there is a problem of peeling between the adhesive and the casing. In addition, the applied adhesive must maintain a fixed gap between the adherends when a load is applied, such as in a semi-hardened state (ie, B-stage state) after light curing.

Therefore, an object of the present invention is to maintain a fixed gap between the adherends during lamination and to prevent peeling of the adherends from easily occurring. [Technical means to solve the problem]

The inventors of the present invention have studied and found that the casings used in mobile phones and the like sometimes have minute strains and uneven surfaces. Since the adhesive is applied along the uneven surfaces, cavities are generated when the parts are attached. Furthermore, the inventors of the present invention have further studied and found that the thickness variation rate after light curing is small, and after applying and curing the coating using a dispenser, the composition is adjusted so that the cured body has a specific shape, thereby solving the above-mentioned problem and completing the present invention. That is, the present invention provides the following [1] to [8]. [1] A curable resin composition comprising a radical polymerizable compound, wherein after the curable resin composition is applied by an air dispenser, the composition is irradiated with 365 nm ultraviolet light at 1000 mJ/ ^cm2 by an LED lamp, and after 16 hours in an environment of 25°C and 50% RH, a ratio of coating height to line width becomes greater than 0.6, and after the composition is irradiated with 365 nm ultraviolet light at 1000 mJ/ ^cm2 by an LED lamp, a load of 0.03 MPa is applied, and the thickness variation rate of the curable resin composition before and after the load is less than 40%. [2] The curable resin composition as described in [1] above, wherein the storage elastic modulus of the cured product of the curable resin composition is 500 MPa or less. [3] The curable resin composition as described in [1] or [2] above, which contains a moisture-curable resin. [4] The curable resin composition as described in any one of [1] to [3] above, wherein the viscosity measured at 25°C and 1 rpm using a cone plate viscometer is 100 Pa·s or more and 1000 Pa·s or less. [5] The curable resin composition as described in any one of [1] to [4] above, wherein the thixotropic index is 1.7 or more and 5.0 or less. [6] The curable resin composition as described in any one of [1] to [5] above, which contains a filler. [7] A curable resin composition as described in any one of [1] to [6] above, which is used as an adhesive for electronic devices. [8] A hardened body, which is a hardened body of the curable resin composition as described in any one of [1] to [7] above. [Effects of the Invention]

According to the curable resin composition of the present invention, the gap between the adherends is kept fixed, and the cavity between the adhesive and the adherend is reduced, so that the adherend is not easily peeled off.

The present invention is described in detail below. [Hardening resin composition] The hardening resin composition of the present invention contains a free radical polymerizable compound and satisfies both the first and second requirements below. The first requirement: After the hardening resin composition is applied using an air dispenser, it is irradiated with 365 nm ultraviolet light at 1000 mJ/ ^cm2 using an LED lamp, and then, after 16 hours in an environment of 25°C and 50% RH, the ratio of the coating height to the line width (hereinafter also referred to as the aspect ratio) becomes 0.6 or more. The second requirement: After the curable resin composition is irradiated with 365 nm ultraviolet light at 1000 mJ/ ^cm2 by an LED lamp, a load of 0.03 MPa is immediately applied, and the thickness change rate of the curable resin composition before and after the load is less than 40%. In addition, the coating conditions of the air distributor in the first requirement are as follows: gap 1.0 mm, nozzle inner diameter 0.4 mm, spray pressure 0.38 MPa, coating speed 1.0 mm/second, coating length 25 mm. In addition, in the measurement of the second requirement, the curable resin composition is coated with a width of 1 mm and a thickness of 0.2 mm, and the thickness change rate is measured in an environment of 25°C.

In the present invention, the aspect ratio after coating and curing is increased as shown in the first requirement. If the aspect ratio after coating and hardening becomes high, even if the adherend is strained and has minute unevenness, and the curable resin composition follows the irregularities, the number of cavities between the adherend and the adherend will become smaller. Therefore, peeling of the adhered body is less likely to occur. From the viewpoint of further reducing the cavity, the aspect ratio is preferably 0.60 or more, more preferably 0.70 or more, and still more preferably 0.80 or more. Moreover, the aspect ratio is not particularly limited, but from the viewpoint of easily maintaining a fixed distance between the gaps between the adherends after lamination, it is preferably 1.0 or less.

The coating conditions shown in the first requirement above are the curing properties after applying and curing the adhesive under the coating conditions in the first requirement above assuming standard coating conditions when applying the adhesive in narrow edge designs, etc. The shape of the resin composition represents the shape of the standard adhesive after application and hardening. Therefore, by adjusting the composition of the curable resin composition in such a way that it becomes the first requirement mentioned above, the cavity between the adhesive and the adherend can be reduced in a narrow edge design or the like.

Furthermore, in the present invention, as described above, if the aspect ratio is increased, generally speaking, the curable resin composition tends to be compressed between the adherends, and there is a situation where it is difficult to maintain the gap between the adherends at a fixed distance or more. However, as in the second requirement mentioned above, by setting the thickness variation rate to 40% or less, the gap can be maintained at a fixed distance or more. From the perspective of making the gap retention good, the thickness variation rate is preferably 30% or less, and more preferably 20% or less. Furthermore, from the perspective of gap retention, the smaller the thickness variation rate, the better, and it can be 0% or more, but from the perspective of ensuring the adhesion or close contact between the adherends, it is preferably 3% or more, and more preferably 7% or more. In the present invention, as described below, the first and second requirements can be satisfied by adjusting the type and blending amount of the radical polymerizable compound contained in the curable resin composition, and the blending amount of the filler, etc.

Furthermore, as shown in the first requirement above, in the measurement of the aspect ratio, the curable resin composition is irradiated with light. Therefore, when measuring the aspect ratio, the curable resin composition is photocured by polymerizing the radically polymerizable compound. In addition, since the curable resin composition is left to stand for a predetermined time after being irradiated with light, it is further cured by moisture when it has moisture curability as described below. On the other hand, the thickness change rate in the second requirement is measured immediately after light irradiation. Therefore, even in the case of moisture curability described below, the thickness change rate of the curable resin composition in a so-called B-stage state in which it is light-cured but not moisture-cured is measured.

(Storage elastic modulus) The storage elastic modulus of the cured product of the curable resin composition of the present invention at 25°C is preferably 500 MPa or less. If the storage elastic modulus of the hardened material is 500 MPa or less, it will be easier to absorb impacts acting on the adherend. In addition, the cavities during bonding can also be easily reduced. From the viewpoint of impact absorption and reduction of cavities during bonding, the storage elastic modulus is preferably 100 MPa or less, more preferably 50 MPa or less, and still more preferably 10 MPa or less. Moreover, from the viewpoint of imparting a certain mechanical strength to the hardened material, the storage elastic modulus is preferably 0.1 MPa or more, more preferably 1 MPa or more. In addition, the storage elastic modulus is determined by measuring the cured product by irradiating the curable resin composition with a mercury lamp at 3000 mJ/cm ² and then leaving it in an environment of 23°C and 50RH%. Obtained in 3 days. In addition, the detailed measurement method of the storage elastic modulus is shown in the Examples mentioned later.

(viscosity) The viscosity of the curable resin composition of the present invention is preferably 100 Pa·s or more and 1000 Pa·s or less. When the viscosity is within the above range, when the curable resin composition is applied to an adherend, the workability and applicability are good, and the aspect ratio can be easily increased. In addition, when applying with a dispenser, it is easy to apply with a thin line width. From these viewpoints, the viscosity is more preferably 200 Pa·s or more, further preferably 300 Pa·s or more, and further preferably 800 Pa·s or less, further preferably 600 Pa·s or less. Furthermore, in this manual, the so-called viscosity refers to the viscosity measured at 1 rpm and 25°C using a cone-plate (E-type) viscometer.

(TI value) The curable resin composition of the present invention preferably has a thixotropic index (TI value) of 1.7 or more. If the TI value is 1.7 or more, the fluidity during coating becomes high. On the other hand, the fluidity can be reduced after coating, so the coating properties can be improved and the above-mentioned aspect ratio can be increased. From this point of view, the TI value is more preferably 2.0 or more, further preferably 2.5 or more, and still more preferably 3.0 or more. Moreover, from the viewpoint of practicality, the TI value is preferably 5.0 or less, more preferably 4.7 or less, and still more preferably 4.5 or less. Furthermore, in this specification, the above-mentioned thixotropic index (TI value) means the viscosity measured using a cone and plate viscometer at 25°C and 1 rpm divided by the viscosity measured using a cone and plate viscometer at 25°C and 1 rpm. The value is obtained from the viscosity measured at 10 rpm. The above-mentioned storage elastic modulus, viscosity, and TI value can be determined by appropriately changing the types and amounts of each component used in the radically polymerizable compound and moisture-curable resin, and the types of additives such as fillers, as described in detail below. Adjust according to the quantity and quantity.

The curable resin composition of the present invention preferably contains a moisture-curable resin in addition to the radical polymerizable compound. Here, the curable resin composition contains a moisture-curable resin to become a light-moisture-curable resin composition that cures by light irradiation and moisture. Since the curable resin composition contains a moisture-curable resin in addition to the radical polymerizable compound, it can be cured even without heating. Therefore, when the curable resin composition is cured, damage to the bonding part or the electronic parts around the bonding part due to heating can be prevented. In addition, by having a moisture-curable resin, it is easy to improve the bonding strength after complete curing. The light-moisture curable resin composition is first cured by light, for example, to a B-stage state, which gives a relatively low adhesive force (viscosity), and then further cured by moisture in the air, etc., to become a cured product with sufficient adhesive force. In this way, the objects to be bonded can be temporarily bonded before being formally bonded.

＜Radically polymerizable compound＞ The radically polymerizable compound contained in the curable resin composition may be a photopolymerizable radically polymerizable compound, and is not particularly limited as long as it is a compound having a radically polymerizable functional group in the molecule. Among these, compounds having an unsaturated double bond as a radically polymerizable functional group are preferred, and compounds having a (meth)acrylyl group (hereinafter, also referred to as "(meth)acrylic compounds") are particularly preferred.

Examples of the (meth)acrylic compound include (meth)acrylate compounds, epoxy (meth)acrylates, (meth)acrylic acid amine esters, and the like. In addition, (meth)acrylic acid urethanes do not have residual isocyanate groups. In addition, in this specification, "(meth)acrylyl" means acrylyl or (meth)acrylyl, "(meth)acrylate" means acrylate or methacrylate, and others are similar. The terminology is also the same.

The above-mentioned (meth)acrylate compound may be monofunctional, difunctional, or trifunctional or higher. Examples of the monofunctional (meth)acrylate compounds include: alkyl (meth)acrylates such as methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, t-butyl (meth)acrylate, n-octyl (meth)acrylate, isooctyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, isononyl (meth)acrylate, isodecyl (meth)acrylate, lauryl (meth)acrylate, isotetradecyl (meth)acrylate, and stearyl (meth)acrylate; (meth)acrylates having an alicyclic structure such as cyclohexyl (meth)acrylate, 4-t-butylcyclohexyl (meth)acrylate, 3,3,5-trimethylcyclohexyl (meth)acrylate, isoborneol (meth)acrylate, and dicyclopentenyl (meth)acrylate; and 2-hydroxyethyl (meth)acrylate, ( meth)acrylate, 2-hydroxypropyl (meth)acrylate, (meth)acrylethylene-butylamide, 2-hydroxybutyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, etc.; alkoxyalkyl (meth)acrylates such as 2-methoxyethyl (meth)acrylate, 2-ethoxyethyl (meth)acrylate, 2-butoxyethyl (meth)acrylate, etc.; alkoxyethylene glycol (meth)acrylates such as methoxyethylene glycol (meth)acrylate and ethoxyethylene glycol (meth)acrylate; polyoxyethylene (meth)acrylates such as methoxydiethylene glycol (meth)acrylate, methoxytriethylene glycol (meth)acrylate, methoxypolyethylene glycol (meth)acrylate, ethylcarbitol (meth)acrylate, ethoxydiethylene glycol (meth)acrylate, ethoxytriethylene glycol (meth)acrylate, ethoxypolyethylene glycol (meth)acrylate, etc.

In addition, the (meth)acrylate compound may have an aromatic ring, for example, (meth)acrylate phenylalkyl esters such as benzyl (meth)acrylate and 2-phenylethyl (meth)acrylate; (meth)acrylate phenoxyalkyl esters such as phenoxyethyl (meth)acrylate, etc. Further, it may be a (meth)acrylate having multiple benzene rings such as a fluorene skeleton and a biphenyl skeleton, specifically, fluorene-type (meth)acrylate, ethoxylated o-phenylphenol acrylate, etc. In addition, phenoxypolyethylene (meth)acrylates such as phenoxydiethylene glycol (meth)acrylate, phenoxypolyethylene glycol (meth)acrylate, nonylphenoxydiethylene glycol (meth)acrylate, nonylphenoxypolyethylene glycol (meth)acrylate, etc. can also be listed. Furthermore, examples of the (meth)acrylate compound having an aromatic ring include phthalimide acrylates such as N-acryloxyethylphthalimide.

Furthermore, as monofunctional (meth)acrylate compounds, there can also be listed: tetrahydrofurfuryl (meth)acrylate, alkoxylated tetrahydrofurfuryl (meth)acrylate, cyclic trihydroxymethylpropane formal (meth)acrylate, (meth)acrylate (3-ethyl-3-oxacyclobutyl)methyl ester and other (meth)acrylates having a heterocyclic structure; various imide (meth)acrylates, (meth)acrylate 2,2,2-trifluoroethyl ester, (meth)acrylate 2,2,3,3-tetrafluoro Propyl ester, 1H,1H,5H-octafluoropentyl (meth)acrylate, dimethylaminoethyl (meth)acrylate, diethylaminoethyl (meth)acrylate, 2-(meth)acryloyloxyethyl succinic acid, 2-(meth)acryloyloxyethyl hexahydrophthalic acid, N-acryloyloxyethyl hexahydrophthalimide, 2-(meth)acryloyloxyethyl phthalate-2-hydroxypropyl phthalate, glycidyl (meth)acrylate, 2-(meth)acryloyloxyethyl phosphate, etc. In addition, as the various imide (meth)acrylates mentioned above, in addition to the above-mentioned phthalimide acrylates and hexahydrophthalimides such as N-acryloxyethyl hexahydrophthalimide, there can be listed: phthalimide acrylates such as (meth)acryloxy phthalimide; maleimide acrylates such as maleimide (meth)acrylate; and various acrylimides having an imide group and a (meth)acryl group.

Examples of bifunctional (meth)acrylate 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 Ester, polyethylene glycol di(meth)acrylate, dipropylene glycol di(meth)acrylate, tripropylene glycol di(meth)acrylate, polypropylene glycol di(meth)acrylate, ethylene oxide addition Bisphenol A di(meth)acrylate, propylene oxide addition to bisphenol A di(meth)acrylate, ethylene oxide addition to bisphenol F di(meth)acrylate, di(meth)acrylic acid Dimethylol dicyclopentadienyl ester, neopentyl glycol di(meth)acrylate, ethylene oxide modified isocyanate di(meth)acrylate, (meth)acrylic acid (2- Hydroxy-3-(meth)acryloxy)propyl ester, carbonate diol di(meth)acrylate, polyether diol di(meth)acrylate, polyester diol di(meth)acrylate ester, polycaprolactone diol di(meth)acrylate, polybutadiene diol di(meth)acrylate, etc.

In addition, examples of the trifunctional or higher-functional (meth)acrylate compounds include trihydroxymethylpropane tri(meth)acrylate, ethylene oxide-added trihydroxymethylpropane tri(meth)acrylate, propylene oxide-added trihydroxymethylpropane tri(meth)acrylate, caprolactone-modified trihydroxymethylpropane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, ethylene oxide-added trimerized isocyanate tri(meth)acrylate, glycerol tri(meth)acrylate, propylene oxide-added glycerol tri(meth)acrylate, tri(meth)acryloyloxyethyl phosphate, di-trihydroxymethylpropane tetra(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol penta(meth)acrylate, and dipentaerythritol hexa(meth)acrylate.

As the above-mentioned (meth)acrylate compound, a monofunctional (meth)acrylate compound is preferred, and among these, those having an alicyclic structure or an aromatic ring are preferred as described below. Preferable examples of the (meth)acrylate having an alicyclic structure include: (meth)acrylic acid 4-tert-butylcyclohexyl ester, (meth)acrylic acid 3,3,5-trimethylacrylate Hexahydrophthalamides such as cyclohexyl ester, isocamphenyl (meth)acrylate, dicyclopentenyl (meth)acrylate, N-acryloxyethyl hexahydrophthalamide, etc. Amines, etc. Preferable examples of the (meth)acrylate compound having an aromatic ring include phenoxyalkyl (meth)acrylate, phthalimide acrylates, and the like. Moreover, it is also preferable that the monofunctional (meth)acrylate compound contains a (meth)acrylate having a acyl imide group. As the (meth)acrylate having an amide group, as mentioned above, in addition to hexahydrophthalimide acrylates and phthalimide acrylates, butylene glycol can also be cited Imide acrylates, maleimide acrylates, acrylimines, etc.

As the above-mentioned epoxy (meth) acrylate, for example, there can be cited those obtained by the reaction of epoxy compounds and (meth) acrylic acid. Here, the reaction of epoxy compounds and (meth) acrylic acid can be carried out in the presence of an alkaline catalyst according to a conventional method. The epoxy (meth) acrylate may be monofunctional or multifunctional such as bifunctional, but is preferably multifunctional. Examples of epoxy compounds used as raw materials for synthesizing the epoxy (meth) acrylate 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 addition 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, o-cresol novolac type epoxy resin, dicyclopentadiene novolac type epoxy resin, biphenyl novolac type epoxy resin, naphthol novolac type epoxy resin, glycidylamine type epoxy resin, alkyl polyol type epoxy resin, rubber modified epoxy resin, glycidyl ester compound, bisphenol A type epoxy resin, etc.

Examples of commercially available epoxy (meth)acrylates include EBECRYL860, EBECRYL3200, EBECRYL3201, EBECRYL3412, EBECRYL3600, EBECRYL3700, EBECRYL3701, EBECRYL3702, EBECRYL3703, EBECRYL3800, EBECRYL6040, and EBECRYL RDX63182 (all manufactured by Daicel Allnex); EA-1010, EA-1020, EA-5323, EA-5520, EACHD, and EMA-1020 (all manufactured by Shin-Nakamura Chemical Industries, Ltd.); EPOXY ESTER M-600A, EPOXY ESTER 40EM, EPOXY ESTER 70PA, EPOXY ESTER 200PA, and 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 Chemicals Co., Ltd.), etc.

(Meth)acrylic acid amine ester can be used, for example, what is obtained by reacting a (meth)acrylic acid derivative having a hydroxyl group and an isocyanate compound. Here, the reaction between the isocyanate compound and the (meth)acrylic acid derivative may use a catalytic amount of a tin-based compound or the like as a catalyst. The (meth)acrylic acid amine ester may be monofunctional or polyfunctional such as bifunctional, but is preferably bifunctional. Examples of the isocyanate compound used to obtain (meth)acrylic amine ester include isophorone diisocyanate, 2,4-toluene diisocyanate, 2,6-toluene diisocyanate, hexamethylene diisocyanate, and trisocyanate. Methylhexamethylene diisocyanate, diphenylmethane-4,4'-diisocyanate (MDI), hydrogenated MDI, polymerized MDI, 1,5-naphthalene diisocyanate, norbornane diisocyanate, bentoluidine diisocyanate , styrene diisocyanate (XDI), hydrogenated , 6,11-Undecane triisocyanate and other polyisocyanate compounds. Furthermore, as the isocyanate compound, a chain-extended polyisocyanate compound obtained by the reaction of a polyol and an excess isocyanate compound can also be used. Here, examples of the polyol include ethylene glycol, 1,2-propanediol, glycerol, sorbitol, trimethylolpropane, carbonate diol, polyether diol, polyester diol, and polycaprolactone. Esterdiol etc.

Examples of the (meth)acrylic acid derivative having a hydroxyl group include mono(meth)acrylates of diols such as ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,3-butylene glycol, 1,4-butylene glycol, and polyethylene glycol; mono(meth)acrylates or di(meth)acrylates of triols such as trihydroxymethylethane, trihydroxymethylpropane, and glycerol; and epoxy(meth)acrylates such as bisphenol A epoxy(meth)acrylate.

Among the above-mentioned (meth) acrylate amines, commercially available ones include, for example, M-1100, M-1200, M-1210, and M-1600 (all manufactured by Toa Gosei Co., Ltd.); EBECRYL230, EBECRYL270, EBECRYL8402, EBECRYL8411, EBECRYL8412, EBECRYL8413, EBECRYL8804, EBECRYL8803, EBECRYL8807, EBECRYL9270, EBECRYL210, EBECRYL4827, EBECRYL6700, EBECRYL220, and EBECRYL2220 (all manufactured by Daicel Allnex Co., Ltd.); Artresin UN-9000H, Artresin UN-9000A, Artresin UN-7100, Artresin UN-1255, and Artresin UN-330, Artresin UN-3320HB, Artresin UN-1200TPK, Artresin SH-500B (all manufactured by Negami Industries); 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-440 0, UA-5201P, UA-7100, UA-7200, UA-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), etc.

As the radically polymerizable compound, other radically polymerizable compounds other than those mentioned above can also be suitably used. Examples of other radically polymerizable compounds include N,N-dimethyl(meth)acrylamide, N-(meth)acrylamide, and N-hydroxyethyl(meth)acrylamide. Amine, N,N-diethyl(meth)acrylamide, N-isopropyl(meth)acrylamide, N,N-dimethylaminopropyl(meth)acrylamide, etc. (methyl base) acrylamide compounds; vinyl compounds such as styrene, α-methylstyrene, N-vinyl-2-pyrrolidinone, N-vinyl-ε-caprolactam, etc.

In the present invention, as a free radical polymerizable compound, it is preferred to use a relatively low viscosity compound as described above, for example, it is preferred to use a monofunctional (meth)acrylate compound. If a low viscosity compound is used, as described below, even if the content of the filler is relatively large, the viscosity of the curable resin composition can be low, and the coating property is good. From the above viewpoints, as described above, as a monofunctional (meth)acrylate compound, it is preferred to have at least one of an aromatic ring and an alicyclic structure, and it is also preferred to use a (meth)acrylate compound having an aromatic ring and a (meth)acrylate compound having an alicyclic structure. The content of the monofunctional (meth)acrylate compound having at least one of an aromatic ring and an alicyclic structure is preferably 30% by mass or more, and more preferably 50% by mass or more, based on the total amount of the radical polymerizable compound. There is no particular restriction, but the upper limit is preferably 100% by mass. In addition, as described above, when the radical polymerizable compound contains a (meth)acrylate having an amide group, the content of the (meth)acrylate having an amide group is preferably 5% by mass or more, more preferably 12% by mass or more, and further preferably 24% by mass or more, based on the total amount of the radical polymerizable compound. In addition, the content of the (meth)acrylate having an amide group is preferably 50% by mass or less, and more preferably 40% by mass or less, based on the total amount of the radical polymerizable compound. Furthermore, the (meth)acrylate having an imide group may have an aromatic ring, an alicyclic structure, or neither, but is preferably monofunctional.

<Moisture-curing resin> As the moisture-curing resin used in the present invention, for example, moisture-curing urethane resins, resins containing hydrolyzable silyl groups, moisture-curing cyanoacrylate resins, etc. are listed. Moisture-curing urethane resins and resins containing hydrolyzable silyl groups are preferred, and moisture-curing urethane resins are more preferred. Moisture-curing urethane resins have isocyanate groups. Moisture-curing urethane resins are hardened by the reaction of isocyanate groups in the molecule with moisture in the air or in the adherend. Moisture-curing urethane resins may have only one isocyanate group in one molecule, or may have two or more. Among them, it is preferred to have isocyanate groups at both ends of the main chain of the molecule.

Moisture-curable urethane resin can be obtained by reacting a polyol compound having two or more hydroxyl groups in one molecule and a polyisocyanate compound having two or more isocyanate groups in one molecule. The reaction between the above-mentioned polyol compound and the polyisocyanate compound is usually based on the molar ratio of the hydroxyl group (OH) in the polyol compound and the isocyanate group (NCO) in the polyisocyanate compound [NCO]/[OH]=2.0~ within the range of 2.5.

As the polyol compound as the raw material of the moisture-curable urethane resin, the well-known polyol compounds commonly used for the production of polyurethane can be used, for example, polyester polyol, polyether polyol, polyalkylene polyol, polycarbonate polyol, etc. These polyol compounds can be used alone or in combination of two or more. As the above-mentioned polyester polyol, for example, polyester polyol obtained by the reaction of polycarboxylic acid and polyol, poly-ε-caprolactone polyol obtained by ring-opening polymerization of ε-caprolactone, etc. can be listed. As the above-mentioned polycarboxylic acid as the raw material of polyester polyol, for example, terephthalic acid, isophthalic acid, 1,5-naphthalene dicarboxylic acid, 2,6-naphthalene dicarboxylic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, sebacic acid, dodecanedicarboxylic acid, etc. can be listed. Examples of the polyols used as the raw materials of the polyester polyol include ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,4-butylene glycol, neopentyl glycol, 1,5-pentanediol, 1,6-hexanediol, diethylene glycol, and cyclohexanediol.

Examples of polyether polyols include ethylene glycol, 1,2-propanediol, ring-opened polymers of tetrahydrofuran, ring-opened polymers of 3-methyltetrahydrofuran, and random copolymers of these or their derivatives. Or block copolymer, bisphenol type polyoxyalkylene modified body, etc. Here, the bisphenol-type polyoxyalkylene modification system combines the activity of alkylene oxide (for example, ethylene oxide, propylene oxide, butylene oxide, epoxy isobutane, etc.) and the bisphenol-type molecular skeleton. Polyether polyol obtained by addition reaction of hydrogen part. The polyether polyol can be a random copolymer or a block copolymer. The above-mentioned bisphenol-type polyoxyalkylene modified body preferably 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 A type, F type, S type, etc., and bisphenol A type is preferred.

Examples of polyalkylene polyols include polybutadiene polyol, hydrogenated polybutadiene polyol, hydrogenated polyisoprene polyol, etc. Examples of polycarbonate polyols include polyhexamethylene carbonate polyol, polycyclohexane dimethylene carbonate polyol, etc.

As the polyisocyanate compound that becomes the raw material of the moisture-curing urethane resin, an aromatic polyisocyanate compound or an aliphatic polyisocyanate compound is preferably used. As the aromatic polyisocyanate compound, for example, diphenylmethane diisocyanate, a liquid modified product of diphenylmethane diisocyanate, polymeric MDI, toluene diisocyanate, naphthalene-1,5-diisocyanate, etc. can be listed. Examples of aliphatic polyisocyanate compounds include hexamethylene diisocyanate, trimethyl hexamethylene diisocyanate, lysine diisocyanate, norbornane diisocyanate, trans-cyclohexane-1,4-diisocyanate, isophorone diisocyanate, hydrogenated stubyl diisocyanate, hydrogenated diphenylmethane diisocyanate, cyclohexane diisocyanate, di(isocyanatomethyl)cyclohexane, and dicyclohexylmethane diisocyanate. As polyisocyanate compounds, diphenylmethane diisocyanate and its modified products are preferred from the viewpoint of improving the adhesion after full curing. Polyisocyanate compounds may be used alone or in combination of two or more.

The moisture-curable urethane resin is preferably obtained by using a polyol compound having a structure represented by the following formula (1). By using a polyol compound having a structure represented by the following formula (1), a curable resin composition having excellent adhesion and a soft cured product having good elongation can be obtained, and the compatibility with the free radical polymerizable compound is excellent. In addition, the storage elastic modulus can be easily adjusted to the required range mentioned above. Among them, it is preferred to use a polyether polyol composed of a ring-opening polymer compound of 1,2-propylene glycol, a tetrahydrofuran (THF) compound, or a ring-opening polymer compound of a tetrahydrofuran compound having a methyl group or the like as a substituent. In addition, a ring-opening polymer compound of a tetrahydrofuran compound is more preferred, and polytetramethylene ether glycol is particularly preferred.

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 0 to 4, m is preferably 50 to 200, and n is preferably 1 to 5. Furthermore, the case where l is 0 means that the carbon bonded to R is directly bonded to oxygen. Among the above, the total of n and l is more preferably 1 or more, and more preferably 3 to 6. Moreover, R is more preferably a hydrogen atom or a methyl group, and particularly preferably a hydrogen atom.

The hydrolyzable silicon group-containing resin used in the present invention is hardened by reacting with the hydrolyzable silicon group in the molecule and the moisture in the air or in the adherend. The resin containing a hydrolyzable silicon group may have only one hydrolyzable silicon group per molecule, or may have two or more. Among them, those having hydrolyzable silicon groups at both ends of the main chain of the molecule are preferred. In addition, the above-mentioned resin containing a hydrolyzable silicon group does not include those having an isocyanate group.

The hydrolyzable silyl group is represented by the following formula (2). In formula (2), ^R1 is independently a substituted alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, an aralkyl group having 7 to 20 carbon atoms, or a _{triorganosiloxy} group represented by ^-OSiR23 ( ^R2 is independently a alkyl group having 1 to 20 carbon atoms). In formula (2), X is independently a hydroxyl group or a hydrolyzable group. In formula (2), a is an integer of 1 to 3.

The above-mentioned hydrolyzable group is not particularly limited, and examples thereof include: halogen atom, alkoxy group, alkenyloxy group, aryloxy group, acyloxy group, ketoximate group, amine group, amide group, and acyl group. Amine group, amineoxy group, sulfhydryl group, etc. Among them, in terms of higher activity, a halogen atom, an alkoxy group, an alkenyloxy group, and a acyloxy group are preferred. Moreover, from the viewpoint of stable hydrolyzability and ease of handling, an alkoxy group such as a methoxy group or an ethoxy group is more preferred, and a methoxy group or an ethoxy group is still more preferred. Moreover, from the viewpoint of safety, it is preferable that the compounds released by the reaction are the ethoxy group and the isopropyleneoxy group of ethanol and acetone, respectively.

The number of the hydroxyl group or the hydrolyzable group may be bonded to one silicon atom in the range of 1 to 3. When the number of the hydroxyl group or the hydrolyzable group is bonded to one silicon atom is 2 or more, the groups may be the same or different.

From the viewpoint of curability, a in the above formula (2) is preferably 2 or 3, and particularly preferably 3. From the viewpoint of storage stability, a is preferably 2. Examples of R ¹ in the above formula (2) include alkyl groups such as methyl and ethyl; cycloalkyl groups such as cyclohexyl; aryl groups such as phenyl; aralkyl groups such as benzyl; trimethylsiloxy, chloromethyl, and methoxymethyl. Among them, methyl is preferred.

Examples of the hydrolyzable silicon group include methyldimethoxysilyl group, trimethoxysilyl group, triethoxysilyl group, tris(2-propenoxy)silyl group, and triethoxysilyl group. base, (chloromethyl)dimethoxysilyl, (chloromethyl)diethoxysilyl, (dichloromethyl)dimethoxysilyl, (1-chloroethyl)dimethoxy Silyl, (1-chloropropyl)dimethoxysilyl, (methoxymethyl)dimethoxysilyl, (methoxymethyl)diethoxysilyl, (ethoxymethyl (1-methoxyethyl)dimethoxysilyl, (aminomethyl)dimethoxysilyl, (N,N-dimethylaminomethyl )dimethoxysilyl, (N,N-diethylaminomethyl)dimethoxysilyl, (N,N-diethylaminomethyl)diethoxysilyl, (N -(2-Aminoethyl)aminomethyl)dimethoxysilyl, (acetyloxymethyl)dimethoxysilyl, (acetyloxymethyl)diethoxysilyl wait.

Examples of the resin containing a hydrolyzable silicon group include (meth)acrylic resin containing a hydrolyzable silicon group, an organic polymer having a hydrolyzable silicon group at the end of the molecular chain or at the end of the molecular chain, and an organic polymer containing a hydrolyzable silicon group. Polyurethane resin, etc. The (meth)acrylic resin containing a hydrolyzable silicon group preferably has a repeating structural unit derived from (meth)acrylate and/or alkyl (meth)acrylate containing a hydrolyzable silicon group in the main chain.

Examples of the (meth)acrylate containing a hydrolyzable silicon group include: (meth)acrylic acid 3-(trimethoxysilyl)propyl ester, (meth)acrylic acid 3-(triethoxysilyl)propyl Propyl ester, 3-(methyldimethoxysilyl)propyl (meth)acrylate, 2-(trimethoxysilyl)ethyl (meth)acrylate, 2-(triethyl)acrylate Oxysilyl)ethyl ester, (meth)acrylic acid 2-(methyldimethoxysilyl)ethyl ester, (meth)acrylic acid trimethoxysilyl methyl ester, (meth)acrylic acid triethoxy Silyl methyl ester, (meth)acrylic acid (methyldimethoxysilyl) methyl ester, etc. Examples of the alkyl (meth)acrylate include: (methyl)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth)acrylate, (meth)acrylate n-butyl methacrylate, isobutyl (meth)acrylate, tert-butyl (meth)acrylate, n-pentyl (meth)acrylate, n-hexyl (meth)acrylate, cyclo(meth)acrylate Hexyl ester, n-heptyl (meth)acrylate, n-octyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, n-nonyl (meth)acrylate, n-decyl (meth)acrylate , n-dodecyl (meth)acrylate, stearyl (meth)acrylate, etc.

Specific examples of the method for producing a hydrolyzable silicon group-containing (meth)acrylic resin include a hydrolyzable silicon group-containing (meth)acrylate polymer described in International Publication No. 2016/035718. Synthetic methods, etc. The above-mentioned organic polymer having a hydrolyzable silicon group at the end of the molecular chain or at the end of the molecular chain has a hydrolyzable silicon group at at least one of the end of the main chain and the end of the side chain. The skeleton structure of the main chain is not particularly limited, and examples thereof include saturated hydrocarbon polymers, polyoxyalkylene polymers, (meth)acrylate polymers, and the like.

As the above-mentioned polyoxyalkylene polymer, for example, there can be listed: polymers having a polyoxyethylene structure, a polyoxypropylene structure, a polyoxybutylene structure, a polyoxytetramethylene structure, a polyoxyethylene-polyoxypropylene copolymer structure, a polyoxypropylene-polyoxybutylene copolymer structure, etc. As a method for producing the above-mentioned organic polymer having a hydrolyzable silyl group at the molecular chain end or at the molecular chain end portion, specifically, for example, the method for synthesizing an organic polymer having a cross-linkable silyl group only at the molecular chain end or at the molecular chain end portion described in International Publication No. 2016/035718 can be listed. In addition, as another method for producing the above-mentioned organic polymer having a hydrolyzable silyl group at the molecular chain end or at the molecular chain end portion, for example, there can be cited the method for synthesizing a polyoxyalkylene polymer containing a reactive silyl group described in International Publication No. 2012/117902.

An example of a method for producing the hydrolyzable silicon group-containing polyurethane resin is a method of reacting a polyol compound and a polyisocyanate compound to produce a polyurethane resin, and then reacting a silicon group-containing compound such as a silane coupling agent. Specific examples include a method for synthesizing an urethane oligomer having a hydrolyzable silicon group described in Japanese Patent Application Laid-Open No. 2017-48345.

Examples of the silane coupling agent include vinyltrichlorosilane, vinyltriethoxysilane, vinyltris(β-methoxy-ethoxy)silane, and β-(3,4-epoxy silane). Hexyl)-ethyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, γ-methacryloxypropyl Trimethoxysilane, N-(β-aminoethyl)-γ-aminopropyltrimethoxysilane, N-(β-aminoethyl)-γ-aminopropyltrimethyldimethyl Oxysilane, N-phenyl-γ-aminopropyltrimethoxysilane, γ-chloropropyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-aminopropyltrimethoxysilane , 3-isocyanatopropyltrimethoxysilane, 3-isocyanatopropyltriethoxysilane, etc. Among them, γ-mercaptopropyltrimethoxysilane, 3-isocyanatopropyltrimethoxysilane, and 3-isocyanatopropyltriethoxysilane are preferred. These silane coupling agents can be used alone, or two or more types can be used in combination.

Furthermore, the moisture-curable urethane resin may have both an isocyanate group and a hydrolyzable silyl group. The moisture-curable urethane resin having both an isocyanate group and a hydrolyzable silyl group is preferably manufactured in the following manner: first, a moisture-curable urethane resin having an isocyanate group is obtained by the above method, and then a silane coupling agent is reacted with the moisture-curable urethane resin. Furthermore, the details of the moisture-curable urethane resin having an isocyanate group are as described above. Furthermore, as the silane coupling agent that reacts with the moisture-curing urethane resin, any of the above-listed ones may be appropriately selected, but from the viewpoint of reactivity with isocyanate groups, it is preferred to use a silane coupling agent having an amino group or a butyl group. Preferred specific examples include: N-(β-aminoethyl)-γ-aminopropyltrimethoxysilane, N-(β-aminoethyl)-γ-aminopropyltrimethyldimethoxysilane, N-phenyl-γ-aminopropyltrimethoxysilane, γ-butylpropyltrimethoxysilane, γ-aminopropyltrimethoxysilane, 3-isocyanatepropyltrimethoxysilane, and the like.

Furthermore, the moisture-curable resin may have a radically polymerizable functional group. As a radically polymerizable functional group that the moisture-curable resin may have, a group having an unsaturated double bond is preferred, and in terms of reactivity, a (meth)acrylyl group is particularly preferred. In addition, the moisture-curable resin having a radically polymerizable functional group is not included in the above-mentioned radically polymerizable compound, and is treated as a moisture-curable resin.

The moisture-curable resin can be appropriately selected from the above various resins and one type can be used alone, or two or more types can be used in combination. When two or more types are used in combination, for example, it is preferable to use two or more types of urethane resins in combination, and more preferably, a moisture-curable urethane resin containing a hydrolyzable silicon group and the above-mentioned urethane bond and isocyanate are used in combination. Based on moisture-hardening urethane resin.

The weight average molecular weight of the moisture-curing resin is not particularly limited, but the preferred lower limit is 800, and the preferred upper limit is 30,000. If the weight average molecular weight is within this range, it is easy to adjust the storage elastic modulus, viscosity, etc. of the curable composition to the above range. The weight average molecular weight of the moisture-curing resin has a more preferred lower limit of 2,000, a more preferred upper limit of 25,000, a further preferred lower limit of 2,500, and a further preferred upper limit of 20,000. In addition, in this specification, the above weight average molecular weight is measured by gel permeation chromatography (GPC) and is calculated by polystyrene conversion. As a column for measuring the weight average molecular weight converted to polystyrene by GPC, Shodex LF-804 (manufactured by Showa Denko K.K.) can be cited. In addition, as a solvent used in GPC, tetrahydrofuran can be mentioned.

In the curable resin composition, the total content of the radical polymerizable compound and the moisture curable resin is preferably 60 parts by mass or more, more preferably 75 parts by mass or more, based on 100 parts by mass of the curable resin composition. Preferably it is 80 parts by mass or more. Moreover, the total content may be 100 parts by mass or less relative to the total amount of the curable resin composition, but is preferably 98 parts by mass or less, and further preferably 95 parts by mass or less. If the total content of the radically polymerizable compound and the moisture-curable resin is within a predetermined range, the aspect ratio, thickness change rate, etc. can be easily adjusted within the above range. Furthermore, in the present invention, the curable resin composition may not contain moisture curable resin. In this case, the above total content means the content of the radical polymerizable compound alone.

When the curable resin composition contains a moisture-curable resin, the mass ratio of the moisture-curable resin to the radical polymerizable compound is preferably 0.3 to 6, more preferably 0.5 to 4, and even more preferably 0.75 or more and 3 or less. In the present invention, by setting the blending amounts of the radically polymerizable compound and the moisture-curable resin within the above range, a certain hardness is imparted in the B-stage state, and the thickness change rate can be easily adjusted within the above range. . In addition, it is easy to increase the adhesion force when completely cured by moisture curing, and it is also easy to adjust the above-mentioned storage elastic modulus to a desired range.

Furthermore, in the present invention, as mentioned above, in order to lower the storage elastic modulus of the cured material, the cured material may contain a component that lowers the elastic modulus. Specific examples of such components include, as radically polymerizable compounds, (meth)phenoxyalkyl acrylate, (meth)alkyl acrylate, furfuryl (meth)acrylate, and polyether acrylic acid. Ester acrylic acid amine ester, etc. Furthermore, examples of the moisture-curable resin include moisture-curable urethane resins derived from polyether polyols. In the present invention, any one of the radically polymerizable compound or the moisture-curable resin may contain a component that lowers the elastic modulus, but both may contain a component that lowers the elastic modulus.

(filler) The curable resin composition of the present invention preferably contains a filler. By containing a filler, the TI value and viscosity of the curable resin composition of the present invention can be easily adjusted to fall within the above ranges. In addition, the shape retention after coating is good and the aspect ratio can be increased. As the filler, particulate ones may be used. The primary particle size of the filler is preferably from 1 nm to 100 nm. By setting the primary particle diameter of the filler within this range, the cured resin composition obtained has good coating properties. In addition, it has excellent shape retention after coating and can easily increase the above-mentioned aspect ratio. The primary particle size of the filler is more preferably 3 nm or more and 80 nm or less, and further preferably 5 nm or more and 50 nm or less. In addition, the primary particle size of the filler can be measured by dispersing the filler in a solvent (water, organic solvent, etc.) using a particle size distribution measuring device such as NICOMP 380ZLS (manufactured by PARTICLE SIZING SYSTEMS).

As the filler, an inorganic filler is preferred, and examples thereof include silicon oxide, talc, titanium oxide, zinc oxide, aluminum oxide, calcium carbonate, and the like. Among them, silicon oxide is preferred in that the obtained optical moisture curable resin composition has excellent ultraviolet transmittance.

The filler is preferably hydrophobically surface treated. By hydrophobic surface treatment, the obtained cured resin composition has good shape retention after coating and can easily increase the above-mentioned aspect ratio. Examples of hydrophobic surface treatment include silanization treatment, alkylation treatment, epoxidation treatment, and the like. Among them, from the viewpoint of increasing the aspect ratio, silanization treatment is preferred, and trimethylsilylation treatment is more preferred.

Examples of a method of hydrophobic surface treatment of a filler include a method of treating the surface of the filler using a surface treatment agent such as a silane coupling agent. For example, the above-mentioned trimethylsilylated silicon oxide can be produced by, for example, the following method: synthesizing silicon oxide using a sol-gel method or the like, and spraying hexamethyldisilonitrogen in a mist state while the silicon oxide is flowing. alkane; add silicon oxide to an organic solvent such as alcohol, toluene, and then add hexamethyldisilazane and water, and then use an evaporator to evaporate the water and the organic solvent to dryness.

The content of the filler is, for example, 5 parts by mass or more, preferably 8 parts by mass or more, based on 100 parts by mass of the curable resin composition. By making it 8 parts by mass or more, from the viewpoint of workability and coating properties, the above-mentioned low-viscosity compound can be used as the radical polymerizable compound or the moisture-curable resin, and the shape stability after coating can also be improved. The aspect ratio described above tends to become larger. From these viewpoints, the content of the filler is preferably 9 parts by mass or more, more preferably 10 parts by mass or more. Moreover, from the viewpoint of coating properties, adhesiveness, etc., the content of the filler is preferably 25 parts by mass or less, more preferably 20 parts by mass or less, and still more preferably 16 parts by mass based on 100 parts by mass of the curable resin composition. parts by mass or less. One type of filler may be used alone, or two or more types may be used in combination.

(Photoradical polymerization initiator) In order to ensure photocurability, the curable resin composition of the present invention preferably contains a photoradical polymerization initiator. Examples of photoradical polymerization initiators include: benzophenone compounds, α-aminoalkylphenone, α-hydroxyalkylphenone and other acetophenone compounds; acylphosphine oxide compounds; diocene titanium compounds; oxime ester compounds; benzoin ether compounds; 9-oxysulfide etc. Among them, from the viewpoint of easily adjusting the viscosity value and storage elastic modulus to the specified range, acetophenone compounds are preferred, and α-aminoalkylphenone is more preferred. Commercially available ones among the above-mentioned photoradical polymerization initiators include, for example, IRGACURE184, IRGACURE369, IRGACURE379, IRGACURE379EG, IRGACURE651, IRGACURE784, IRGACURE819, IRGACURE907, IRGACURE2959, IRGACURE OXE01, Lucirin TPO (all manufactured by BASF); benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether (all manufactured by Tokyo Chemical Industry Co., Ltd.), etc.

The content of the photo-radical polymerization initiator in the curable resin composition is preferably 0.01 to 10 parts by mass, and more preferably 0.5 to 5 parts by mass, relative to 100 parts by mass of the radical polymerizable compound. By making the content of the photo-radical polymerization initiator within this range, the obtained curable resin composition has excellent photocurability and storage stability. In addition, by setting it within the above range, the photo-radical polymerizable compound is appropriately cured, and the above storage elastic modulus, aspect ratio, and thickness change rate are easily adjusted to within the specified range.

(Moisture curing accelerating catalyst) The hardening resin composition may contain a moisture curing accelerating catalyst for accelerating the moisture curing reaction of the moisture curing resin. By using the moisture curing accelerating catalyst, the hardening resin composition becomes one with better moisture curability, and the adhesion can be further improved. Specifically, as the moisture curing accelerating catalyst, for example, tin compounds such as di-n-butyltin dilaurate, di-n-butyltin diacetate, and stannous octoate; amine compounds such as triethylamine, U-CAT651M (manufactured by San-Apro Ltd.), U-CAT660M (manufactured by San-Apro Ltd.), U-CAT2041 (manufactured by San-Apro Ltd.), 1,4-diazabicyclo[2.2.2]octane, and 2,6,7-trimethyl-1,4-diazabicyclo[2.2.2]octane; zinc compounds such as zinc octanoate and zinc cycloalkanoate; zirconium tetraacetylpyruvate, copper cycloalkanoate, and cobalt cycloalkanoate, etc. can be used. The content of the moisture curing accelerating catalyst is preferably 0.01 to 10 parts by mass, and more preferably 0.1 to 7 parts by mass, relative to 100 parts by mass of the curable resin composition. By making the content of the moisture curing accelerating catalyst within this range, the storage stability of the curable resin composition is not deteriorated and the effect of accelerating the moisture curing reaction is excellent.

(Coupling agent) The curable resin composition may contain a coupling agent. By containing a coupling agent, it is easy to improve the adhesion. As coupling agents, for example, silane coupling agents, titanium ester coupling agents, zirconate coupling agents, etc. can be listed. Among them, silane coupling agents are preferred in terms of the excellent effect of improving adhesion. The above coupling agents can be used alone or in combination of two or more. The content of the coupling agent is preferably 0.05 mass parts to 5 mass parts, and more preferably 0.2 mass parts to 3 mass parts, relative to 100 mass parts of the curable resin composition. By making the content of the coupling agent within these ranges, various physical properties are not affected and the adhesion is improved. In addition to the above-mentioned components, the curable resin composition may also contain other additives such as wax particles, ionic liquid, coloring agent, foaming particles, expanding particles, reactive diluents, etc.

The curable resin composition of the present invention may be diluted with a solvent as needed. When the curable resin composition is diluted with a solvent, the mass of the curable resin composition is based on the solid content, that is, the mass excluding the solvent.

As a method for producing the curable resin composition of the present invention, there can be listed a method of mixing a radical polymerizable compound, a moisture curable resin, and other additives such as a photo radical polymerization initiator and a filler as required using a mixer. Examples of the mixer include a homogeneous disperser, a homomixer, a universal mixer, a planetary mixer (planetary stirring device), a kneader, and a three-roll grinder.

[How to use curable resin composition] The curable resin composition of the present invention is cured and used in the form of a cured body. The curable resin composition of the present invention is at least photocured by light irradiation. The curable resin composition of the present invention, for example, can join the adherends by being cured while being disposed between the adherends. At this time, it is sufficient to apply the resin composition to one adherend, and then overlap the other adherend on the one adherend through the applied curable resin composition.

Moreover, in the case of the optical moisture curing type, it is sufficient to perform photocuring by irradiation with light to achieve, for example, a B-stage state (semi-cured state), and then further curing by moisture to completely cure it. . Here, when the optical moisture curing type curable resin composition is disposed between the adherends to join the adherends, it is applied to one adherend and then irradiated with light. For photohardening, for example, to achieve a B-stage state, another adherend can be overlapped on the photocured curable resin composition, and the adherends can be temporarily bonded with a moderate adhesive force (initial adhesive force). Thereafter, the curable resin composition in the B-stage state is completely cured by curing the moisture curable resin with moisture, and the adherends overlapped via the curable resin composition are joined with sufficient adhesion force.

The application of the curable resin composition to the adherend is preferably performed using a dispenser. Examples of the dispenser include air dispensers, jet dispensers, Mono pump dispensers, screw dispensers, handgun dispensers, etc., but are not particularly limited. In addition, the light irradiated during photocuring can be light that cures the free radical polymerizable compound, and is not particularly limited, but is preferably ultraviolet light. In addition, when the curable resin composition is completely cured by moisture, it can be left in the atmosphere for a specified time.

The curable resin composition of the present invention is preferably used as an adhesive for electronic equipment. Therefore, the adherend is not particularly limited, but is preferably various parts constituting the electronic equipment. Various parts constituting the electronic equipment include electronic parts, substrates with electronic parts mounted thereon, and more specifically, various electronic parts provided on display elements, substrates with electronic parts mounted thereon, semiconductor chips, and the like. The material of the adherend may be any one of metal, glass, plastic, and the like. Furthermore, the shape of the adherend is not particularly limited, and may include, for example, film, sheet, plate, panel, disk, rod (rod-shaped body), box, shell, and the like.

For example, the curable resin composition of the present invention is used in the interior of electronic equipment, etc., for example, to bond substrates to substrates to obtain assembled parts. The assembled part obtained in this way has a first substrate, a second substrate, and the hardened body of the present invention, and at least a part of the first substrate is joined to at least a part of the second substrate through the hardened body. Furthermore, it is preferable that at least one electronic component is mounted on the first substrate and the second substrate respectively.

In addition, the curable resin composition of the present invention is preferably used for narrow edge applications. For example, in various portable devices with display components such as smart phones, portable game consoles, etc., an adhesive is applied on a narrow square frame-shaped substrate (i.e., narrow edge), and a display panel, touch panel, etc. are assembled through the adhesive. In the present invention, a curable resin composition is used as the adhesive. Furthermore, the curable resin composition of the present invention is preferably used for semiconductor chip applications. The curable resin composition of the present invention is used in semiconductor chip applications, for example, to bond semiconductor chips to each other.

In semiconductor chips or narrow edge applications, the adhesive needs to be applied to a narrow width of, for example, 0.2 to 2 mm, preferably 0.3 to 1.0 mm. The curable resin composition of the present invention can be applied to such a narrow width because it has the above-mentioned various properties (TI value, viscosity, etc.). Moreover, even if it is applied to a narrow width, by satisfying the first requirement, the cavity between the curable resin composition and the adherend is reduced, so it is not easy to produce peeling of the adherend. Furthermore, by satisfying the second requirement, even if a load is applied to the curable resin composition, the thickness will not change significantly, so the gap between the adherends can be maintained fixed. Implementation Example

The present invention will be further described in detail through examples, but the present invention is not limited by these examples in any way.

In this example, various physical properties were measured and evaluated in the following manner. ＜Viscosity, and TI value＞ The viscosity was measured using a cone-plate viscometer (trade name: TVE-35, manufactured by Toki Industrial Co., Ltd.) at 1 rpm and 25°C. In addition, the TI value is the value obtained by dividing the viscosity measured at 25°C and 1 rpm by the viscosity measured at 25°C and 10 rpm using the same cone and plate viscometer.

<Storage elastic modulus> The curable resin composition is poured into a Teflon (registered trademark) mold with a width of 3 mm, a length of 30 mm, and a thickness of 1 mm, and is hardened to obtain a hardened body. The hardening of the curable resin composition is carried out as follows: photohardening by irradiation with a mercury lamp at 3000 mJ/ ^cm2 , and then left for 3 days in an environment of 23°C and 50RH% to allow moisture to be removed. Gas hardening. Using the obtained hardened body, the dynamic viscoelasticity was measured in the range of -100°C to 150°C using a dynamic viscoelasticity measuring device (manufactured by IT Meter. and Control, Inc., trade name: "DVA-200") to find out The storage elastic modulus at room temperature (25°C) is given. The measurement conditions are that the deformation mode is tensile, the set strain is 1%, the measurement frequency is 1 Hz, and the temperature rise rate is 5°C/min.

<Aspect ratio> Use an air distributor ("SHOTMASTER200DS", manufactured by Musashi High-tech Co., Ltd.) to coat a polycarbonate substrate (trade name: "Iupilon GSH2010LR-Y082 GF10%", manufactured by Mitsubishi Engineering-Plastics) and heat it to 50℃ resin. The coating conditions are as follows: the gap is 1.0 mm, the inner diameter of the nozzle is 0.4 mm, the spray pressure is 0.38 MPa, the speed is 1.0 mm/second, and the coating length is 25 mm. Use an LED lamp (trade name "EXECURE H-1VC2", manufactured by HOYA CANDEO OPTRONICS, head unit "H-1VH-01" used) to apply 1000 mJ/cm ² to the curable resin composition 5 seconds after completion of coating. Irradiated with 365 nm ultraviolet light. Next, after leaving it in an environment of 25°C and 50% RH for 16 hours, the width (maximum width) and height of the cured resin were measured using a laser microscope (trade name "VK-X200", manufactured by Keyence Corporation) (Maximum height), calculate the ratio of the height of the hardened object to the width as the aspect ratio.

<Thickness variation rate> An aluminum substrate (length 72 mm, width 52 mm, thickness 2 mm) was prepared, and a curable resin composition was applied on one surface of the substrate along the outer edge of the substrate all around. The curable resin composition was applied in such a way that the line width became 1 mm and the thickness became 0.2 mm. Next, the applied curable resin composition was irradiated with 365 nm ultraviolet light at 1000 mJ/ ^cm2 using an LED lamp to photocure it. Thereafter, a glass substrate of the same size as the aluminum substrate was superimposed on the photocured curable resin composition in an environment of 25°C and a weight of 280 g was applied, thereby applying a load of 0.03 MPa and measuring the thickness variation rate. If the thickness of the curable resin composition before the glass substrates are stacked is A, and the thickness of the curable resin composition after the glass substrates are stacked and a weight of 280 g is applied for 10 seconds is B, the thickness change rate is measured by (AB)/A×100. In addition, as an evaluation of the gap forming property, the thickness change rate is evaluated as AA when it is 30% or less, A when it is more than 30% and less than 40%, and B when it is more than 40%. In addition, the thickness of the curable resin composition was measured by observation using a digital microscope (trade name "KH-7800", manufactured by HIROX Corporation).

<Cavity during bonding> Prepare an aluminum substrate (length 72 mm, width 52 mm, thickness 2 mm), and apply a curable resin composition to the substrate in a manner that the outer circumference becomes 70 mm × 48 mm. The curable resin composition is applied in a manner that the line width becomes 0.4 mm. Next, the applied curable resin composition is irradiated with 365 nm ultraviolet light at 1000 mJ/cm ² using an LED lamp to photocure it. Thereafter, a glass substrate of the same size as the aluminum substrate is superimposed on the photocured curable resin composition and a 200 g weight is applied for 10 seconds. The test piece was observed using a digital microscope (trade name: "KH-7800", manufactured by HIROX Corporation), and the evaluation was B if there was even one cavity, and A if there was no cavity.

Moisture-curable urethane resin A was produced 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") as a polyol compound and 0.01 parts by mass of dibutyltin dilaurate were charged to a capacity of 500 mL. In a separable flask, mix under vacuum (below 20 mmHg) at 100°C for 30 minutes. Then, the pressure was adjusted to normal, and 26.5 parts by mass of diphenylmethane diisocyanate (manufactured by Nisso Corporation, trade name "Pure MDI") as a polyisocyanate compound was added, and the mixture was stirred at 80° C. for 3 hours to react. , to obtain a moisture-hardening urethane resin (weight average molecular weight: 2700).

Moisture-curable urethane resin B was prepared according to the following Synthesis Example 2. [Synthesis Example 2] 100 parts by mass of polycaprolactone (manufactured by Daicel, trade name "PLACCEL H1P") as a polyol compound and 0.01 parts by mass of dibutyltin dilaurate were placed in a 500 mL separable flask and stirred at 100°C for 30 minutes under vacuum (less than 20 mmHg) to mix. Thereafter, 5.3 parts by mass of diphenylmethane diisocyanate (manufactured by Nissou Shoji, trade name "Pure MDI") as a polyisocyanate compound was added to the mixture under normal pressure, and the mixture was stirred at 80°C for 3 hours to react to obtain a moisture-curable urethane resin (weight average molecular weight of 12,000).

The components other than the moisture-curable urethane resin used in each embodiment and comparative example are as follows. Monofunctional acrylate 1: phenoxyethyl acrylate (manufactured by Kyoeisha Chemical Co., Ltd., "Light acrylate PO-A") Monofunctional acrylate 2: isoborneol acrylate (manufactured by Daicel Allnex, "IBOAB") Monofunctional acrylate 3: N-acryloyloxyethyl hexahydroxylphenyl dimethamide (manufactured by Toagosei Co., Ltd., "ARONIX M-140") Photoradical polymerization initiator: 2-benzyl-2-dimethylamino-1-(4-oxoformylphenyl)-butanone-1-(manufactured by BASF, "IRGACURE369") Moisture curing accelerator: U-CAT660M (manufactured by San-Apro Ltd.) Filler: trimethylsilylated silica (manufactured by Japan Aerosil Co., Ltd., "R812", primary particle size 7 nm)

[Examples 1 to 6, Comparative Examples 1 to 3] According to the blending ratio described in Table 1, stir each material using a planetary stirring device ("Defoaming Mixing Taro" manufactured by Thinky Corporation) at a temperature of 50°C, and then mix uniformly using a ceramic three-roller mill at a temperature of 50°C. , and the curable resin compositions of Examples 1 to 6 and Comparative Examples 1 to 3 were obtained.

[Table 1] Embodiment Comparison Example 1 2 3 4 5 6 1 2 3 Composition (mass) Moisture-hardening resin Moisture-hardening urethane resin A 44 60 44 62 48 67 Moisture-hardening urethane resin B 44 44 44 Free radical polymerizable compounds Monofunctional acrylate 1 29 15 29 twenty four 32 twenty four Monofunctional acrylate 2 29 29 36 Monofunctional acrylate 3 15 9 15 15 15 5 15 15 Photoradical polymerization initiator 1 1 1 1 1 1 1 1 1 Moisture Hardening Catalyst 1 1 1 1 1 1 1 1 1 Filler 10 14 10 10 10 7 3 3 7 Total 100 100 100 100 100 100 100 100 100 Physical properties Viscosity (Pa·s (1 rpm)) 342 525 381 490 518 350 62 98 362 Trigger index 2.8 3.9 2.9 3.2 3.2 2.7 1.6 1.3 2.6 Thickness change rate before and after loading (%) 18 26 6 15 3 38 4 10 42 Aspect Ratio 0.71 0.92 0.72 0.76 0.85 0.62 0.34 0.3 0.61 Storage elastic modulus at 25℃ (MPa) 8 10 86 98 250 15 210 6 16 Gap Formation AA AA AA AA AA A AA AA B Cavity during bonding A A A A A A B B A

As shown in Examples 1 to 6 above, the curable resin composition can reduce the cavity during bonding by making the aspect ratio of the coating and curing to be 0.6 or more, so it is not easy to produce peeling. In addition, even if a load is applied, the thickness change rate is small, so it is easy to form a fixed gap between the adherends despite the large longitudinal and transverse ratios. In contrast, in Comparative Examples 1 to 3, the curable resin composition has a relatively small longitudinal and transverse ratio after coating and curing, so it is impossible to reduce the cavity during bonding and peeling is easy to occur.

without

without

Claims (8)

A curable resin composition containing a radically polymerizable compound is prepared by using an air dispenser with a gap of 1.0 mm, an inner diameter of a nozzle of 0.4 mm, a discharge pressure of 0.38 MPa, and a coating speed of 1.0 mm/second. After coating the above-mentioned curable resin composition with a coating length of 25mm, use an LED lamp to irradiate 365nm ultraviolet light at 1000mJ/ ^cm2 , and leave it in an environment of 25℃ and 50%RH for 16 hours. At this time, the coating height is relative to The line width ratio becomes 0.6 or more, and after irradiating ultraviolet light of 365nm with an LED lamp at 1000mJ/ ^cm2 , a load is applied at 0.03MPa, and the thickness change rate of the above-mentioned curable resin composition before and after the load is 40% or less; wherein , the measurement conditions of the thickness change rate are to apply the curable resin composition with a width of 1 mm and a thickness of 0.2 mm, and measure it in an environment of 25°C. The curable resin composition according to claim 1, wherein the storage elastic modulus of the cured product of the curable resin composition is 500 MPa or less. The hardening resin composition as described in claim 1 or 2 contains a moisture-hardening resin. The viscosity of the curable resin composition as described in claim 1 or 2, measured using a cone-type viscometer at 25°C and 1 rpm, is 100 Pa. s or more and 1000 Pa. s or less. The curable resin composition according to claim 1 or 2 has a thixotropic index of 1.7 or more and 5.0 or less. The hardening resin composition as described in claim 1 or 2, which contains a filler. The curable resin composition according to claim 1 or 2, which is used as an adhesive for electronic devices. A hardened body, which is a hardened body of the hardening resin composition described in any one of claims 1 to 7.