WO2018030435A1 - Adhesive composition, cured body, electronic component, and assembly component - Google Patents

Abstract

One purpose of the present invention is to provide an adhesive composition that exhibits superior adhesiveness and is easy to rework at low temperatures. Another purpose of the present invention is to provide a cured body of said adhesive composition, as well as an electronic component and assembly component comprising the cured body of said adhesive composition. The present invention is an adhesive composition containing a moisture-curing resin and a wax.

Description

Adhesive composition, cured body, electronic component and assembly component

The present invention relates to an adhesive composition that is excellent in adhesiveness and easy to rework at a low temperature. The present invention also relates to a cured product of the adhesive composition, and an electronic component and an assembly component having the cured product of the adhesive composition.

In recent years, liquid crystal display elements, organic EL display elements, and the like are widely used as display elements having features such as thinness, light weight, and low power consumption. In these display elements, a photocurable resin composition is usually used for sealing a liquid crystal or a light emitting layer, adhering various members such as a substrate, an optical film, and a protective film. Further, in the present age when mobile devices with various display elements such as mobile phones and portable game machines are widespread, downsizing of display elements is the most demanded issue.
However, with the miniaturization of the display element, the photocurable resin composition may be applied to a portion where light does not reach sufficiently. As a result, the photocurable resin composition applied to a portion where light does not reach Had the problem of insufficient curing. Therefore, a photothermosetting resin composition is used as a resin composition that can be sufficiently cured even when applied to a portion where light does not reach, and photocuring and thermosetting are also used in combination. There was a possibility of adversely affecting the elements and the like by heating.

In recent years, electronic components such as semiconductor chips have been required to be highly integrated and miniaturized. For example, a plurality of thin semiconductor chips can be bonded via an adhesive layer to form a stacked body of semiconductor chips. Has been done. Such a semiconductor chip laminate is, for example, a method in which an adhesive is applied on one semiconductor chip, and then the other semiconductor chip is laminated via the adhesive, and then the adhesive is cured. It is manufactured by a method of filling an adhesive between semiconductor chips held at intervals and then curing the adhesive.
As an adhesive used for bonding such electronic parts, for example, Patent Document 1 discloses a thermosetting adhesive containing an epoxy compound having a number average molecular weight of 600 to 1,000. However, the thermosetting adhesive as disclosed in Patent Document 1 is not suitable for bonding electronic components that may be damaged by heat.

As a method for curing a resin composition without heating at a high temperature, a method using a moisture curable resin composition has been studied. For example, Patent Document 2 discloses a moisture curable resin composition that is crosslinked and cured by reacting an isocyanate group in a resin with moisture (moisture) in air or an adherend. However, the thermosetting adhesive as disclosed in Patent Document 1 is not suitable for bonding electronic components that may be damaged by heat. In addition, since a thermosetting adhesive is likely to deteriorate in adhesive properties when a large load is applied for a long time, it is difficult to obtain a highly reliable adhesive.

JP 2000-178342 A Japanese Patent Laid-Open No. 2002-212534

Recently, the present inventors have come up with the idea of a new type of moisture curable resin composition imparted with reworkability. However, the moisture curable resin composition as described above has adhesiveness and reworkability (removability). ) Is difficult to achieve. In particular, when reworking is performed under high temperature conditions, there is a problem of damaging electronic components, etc., so that it does not require heating at high temperatures when fixed, and has excellent adhesiveness. It was necessary to study a resin composition that can be easily peeled off by heating.
An object of this invention is to provide the adhesive composition which is excellent in adhesiveness and is easy to rework at low temperature. The present invention also provides a cured product of the adhesive composition, and an electronic component and an assembly component having the cured product of the adhesive composition.

The present invention is an adhesive composition containing a moisture curable resin and a wax.
The present invention is described in detail below.

The present inventors have found that an adhesive composition having excellent adhesiveness and easy reworking at a low temperature can be obtained by blending a wax with a moisture curable resin composition, and the present invention has been completed. I came to let you.

The adhesive composition of the present invention contains a wax.
By containing the wax, the adhesive composition of the present invention is excellent in reworkability because the cured product is softened by heating during rework and the adhesive strength is significantly reduced.
In the present specification, the “wax” means an organic substance that is solid at 23 ° C. and becomes liquid when heated.

The preferable lower limit of the melting point of the wax is 50 ° C., and the preferable upper limit is 140 ° C. When the melting point of the wax is within this range, the resulting adhesive composition is more excellent in the effect of achieving both adhesiveness and reworkability. A more preferred lower limit of the melting point of the wax is 70 ° C., and a more preferred upper limit is 110 ° C.
The melting point of the wax is a temperature showing the peak top of the endotherm in the graph obtained by differential scanning calorimetry.

When the wax is present in the adhesive composition of the present invention in the form of fine particles (hereinafter also referred to as “wax fine particles”), the contact area between the resin and the wax becomes large, and the resulting adhesive composition has reworkability. This is preferable because it becomes more excellent.
The particle diameter of the wax fine particles is preferably as small as possible, and the preferable upper limit is 300 μm. When the particle diameter of the wax fine particles is 300 μm or less, the obtained adhesive composition is more excellent in reworkability. A more preferable upper limit of the particle diameter of the wax fine particles is 250 μm, a further preferable upper limit is 100 μm, a still more preferable upper limit is 50 μm, and a particularly preferable upper limit is 10 μm.
Moreover, there is no particular lower limit for the particle diameter of the wax fine particles, but a substantial lower limit is 0.1 μm.
The particle size of the wax fine particles is, for example, a scanning electron microscope, a laser microscope, a laser diffraction particle size distribution measuring device, a disk centrifugal particle size distribution measuring device, a number counting type when measuring wax fine particles as a raw material. It can be measured by a particle size distribution measuring device or the like. When measuring the wax fine particles present in the adhesive composition of the present invention, it can be measured by a scanning electron microscope, a transmission electron microscope, a laser microscope or the like. As a preferred measurement method, when measuring wax fine particles as a raw material, a method using a “laser diffraction particle size distribution measuring device”, and when measuring wax fine particles present in the adhesive composition of the present invention, This is a method using a “scanning electron microscope”.

Specific examples of the wax include, for example, olefinic wax or paraffinic wax such as polypropylene wax, polyethylene wax, microcrystalline wax, and oxidized polyethylene wax, and aliphatic such as carnauba wax, sazol wax, and montanic ester wax. Ester wax, deacidified carnauba wax, saturated aliphatic acid wax such as baltimic acid, stearic acid, montanic acid, unsaturated aliphatic acid wax such as pracidic acid, eleostearic acid, valinalic acid, Saturated alcohol wax or aliphatic alcohol wax such as stearyl alcohol, aralkyl alcohol, behenyl alcohol, carnauvir alcohol, seryl alcohol, melyl alcohol, and polyhydric alcohol such as sorbitol Wax, saturated fatty acid amide wax such as linoleic acid amide, oleic acid amide, lauric acid amide, methylene bis stearic acid amide, ethylene biscapric acid amide, ethylene bis lauric acid amide, hexamethylene bis stearic acid amide Saturated fatty acid bisamide wax such as ethylene bisoleic acid amide, hexamethylene bisoleic acid amide, N, N′-dioleyl adipic acid amide, N, N′-dioleyl sebacic acid amide, etc. Wax, aromatic bisamide waxes such as m-xylenebisstearic acid amide and N, N'-distearylisophthalic acid amide, graft modified waxes obtained by graft polymerization of vinyl monomers such as styrene onto polyolefins, behenic acid Monoglyceride Ester waxes obtained by reacting various fatty acids with polyhydric alcohols, methyl ester waxes obtained by hydrogenating vegetable oils and fats, and ethylene / vinyl acetate copolymer waxes with a high content of ethylene components And long-chain alkyl acrylate waxes such as saturated stearyl acrylate waxes such as acrylic acid, and aromatic acrylate waxes such as benzyl acrylate waxes. Of these, paraffin wax and sazol wax are preferable.

Among the waxes that are commercially available, for example, HS crystal 6100, HS crystal 7100 (both manufactured by Toyokuni Seiyaku), H1, H1N6, C105, H105, C80, SPRAY30, SPRAY105 (all are Sasol). ), ParaffinWax-155, ParaffinWax-150, ParaffinWax-145, ParaffinWax-140, HNP-3, HNP-9, HNP-51, SP-0165, Hi-Mic-2095, Hi-Mic-1090, Hi- Mic-1080, Hi-Mic-1070, NPS-6010, FT115, SX105, FNP-0090 (all manufactured by Nippon Seiwa Co., Ltd.) and the like.

A preferable lower limit of the content of the wax in 100 parts by weight of the adhesive composition of the present invention is 1 part by weight, and a preferable upper limit is 50 parts by weight. When the content of the wax is within this range, the resulting adhesive composition is more excellent in the effect of achieving both adhesiveness and reworkability. The more preferable lower limit of the wax content is 3 parts by weight, the more preferable upper limit is 40 parts by weight, the still more preferable lower limit is 5 parts by weight, and the still more preferable upper limit is 30 parts by weight.

The adhesive composition of the present invention contains a moisture curable resin.
Examples of the moisture curable resin include a moisture curable urethane resin and a hydrolyzable silyl group-containing resin. Especially, it is preferable that it is a moisture hardening type urethane resin.
The moisture curable urethane resin has a urethane bond and an isocyanate group, and the isocyanate group in the molecule is cured by reacting with moisture in the air or the adherend.

The moisture curable urethane resin may have only one isocyanate group in one molecule, or may have two or more. Especially, it is preferable to have an isocyanate group at both ends of the main chain of the molecule.

The moisture curable urethane resin 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 polyol compound and the polyisocyanate compound is usually [NCO] / [OH] = 2.0 to 2 in terms of the molar ratio of the hydroxyl group (OH) in the polyol compound to the isocyanate group (NCO) in the polyisocyanate compound. .5 in the range.

As a polyol compound used as a raw material for the moisture curable urethane resin, a known polyol compound usually used in the production of polyurethane can be used. For example, polyester polyol, polyether polyol, polyalkylene polyol, polycarbonate polyol Etc. These polyol compounds may be used independently and may be used in combination of 2 or more type.

Examples of the polyester polyol include a polyester polyol obtained by reaction of a polyvalent carboxylic acid and a polyol, and a poly-ε-caprolactone polyol obtained by ring-opening polymerization of ε-caprolactone.

Examples of the polyvalent carboxylic acid used as a raw material for the polyester polyol include terephthalic acid, isophthalic acid, 1,5-naphthalic acid, 2,6-naphthalic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, and suberin. Examples include acid, azelaic acid, sebacic acid, decamethylene dicarboxylic acid, dodecamethylene dicarboxylic acid and the like.

Examples of the polyol used as a raw material for the polyester polyol include ethylene glycol, propylene glycol, 1,3-propanediol, 1,4-butanediol, neopentyl glycol, 1,5-pentanediol, and 1,6-hexane. Diol, diethylene glycol, cyclohexanediol, etc. are mentioned.

Examples of the polyether polyol include ethylene glycol, propylene glycol, ring-opening polymer of tetrahydrofuran, ring-opening polymer of 3-methyltetrahydrofuran, and random copolymers or block copolymers of these or derivatives thereof, bisphenol Type polyoxyalkylene modified products.

The modified bisphenol-type polyoxyalkylene is a polyether polyol obtained by addition reaction of alkylene oxide (for example, ethylene oxide, propylene oxide, butylene oxide, isobutylene oxide, etc.) to the active hydrogen portion of the bisphenol-type molecular skeleton, A random copolymer or a block copolymer may be used. The modified bisphenol-type polyoxyalkylene preferably has one or more alkylene oxides added to both ends of the bisphenol-type molecular skeleton. It does not specifically limit as a bisphenol type, A type, F type, S type etc. are mentioned, Preferably it is bisphenol A type.

Examples of the polyalkylene polyol include polybutadiene polyol, hydrogenated polybutadiene polyol, and hydrogenated polyisoprene polyol.

Examples of the polycarbonate polyol include polyhexamethylene carbonate polyol and polycyclohexane dimethylene carbonate polyol.

As the polyisocyanate compound used as a raw material for the moisture-curable urethane resin, an aromatic polyisocyanate compound and an aliphatic polyisocyanate compound are preferably used.
Examples of the aromatic polyisocyanate compound include diphenylmethane diisocyanate, a liquid modified product of diphenylmethane diisocyanate, polymeric MDI, tolylene diisocyanate, naphthalene-1,5-diisocyanate, and the like.
Examples of the aliphatic polyisocyanate compound include hexamethylene diisocyanate, trimethylhexamethylene diisocyanate, lysine diisocyanate, norbornane diisocyanate, transcyclohexane-1,4-diisocyanate, isophorone diisocyanate, hydrogenated xylylene diisocyanate, hydrogenated diphenylmethane diisocyanate, and cyclohexane. Examples include diisocyanate, bis (isocyanatemethyl) cyclohexane, dicyclohexylmethane diisocyanate, and the like.
Among the above polyisocyanate compounds, diphenylmethane diisocyanate and modified products thereof are preferable from the viewpoint of low vapor pressure, low toxicity, and ease of handling.
The said polyisocyanate compound may be used independently and may be used in combination of 2 or more type.

Moreover, it is preferable that the said moisture hardening type urethane resin is obtained using the polyol compound which has a structure represented by following formula (1). By using a polyol compound having a structure represented by the following formula (1), it is possible to obtain a composition excellent in adhesiveness and a cured product that is flexible and has good elongation, and a phase with a radical polymerizable compound described later. Excellent solubility.
Among these, those using a polyether polyol composed of a ring-opening polymerization compound of propylene glycol, a tetrahydrofuran (THF) compound, or a ring-opening polymerization compound of a tetrahydrofuran compound having a substituent such as a methyl group are preferable.

In the formula (1), R represents a hydrogen atom, a methyl group, or an ethyl group, l is an integer of 0 to 5, m is an integer of 1 to 500, and n is an integer of 1 to 10. . l is preferably from 0 to 4, m is preferably from 50 to 200, and n is preferably from 1 to 5.
The case where l is 0 means that the carbon bonded to R is directly bonded to oxygen.

In the hydrolyzable silyl group-containing resin, the hydrolyzable silyl group in the molecule is cured by reacting with moisture in the air or in the adherend.
The hydrolyzable silyl group-containing resin may have only one hydrolyzable silyl group in one molecule, or may have two or more. Especially, it is preferable to have a hydrolyzable silyl group at both ends of the main chain of the molecule.

The hydrolyzable silyl group is represented by the following formula (2).

In formula (2), each R ¹ independently represents an optionally 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 , —OSiR ² ₃ (wherein R ² is each independently a hydrocarbon group having 1 to 20 carbon atoms). Moreover, in Formula (2), X is a hydroxyl group or a hydrolysable group each independently. In the formula (2), a is an integer of 1 to 3.

The hydrolyzable group is not particularly limited, and examples thereof include a hydrogen atom, a halogen atom, an alkoxy group, an alkenyloxy group, an aryloxy group, an acyloxy group, a ketoximate group, an amino group, an amide group, an acid amide group, an aminooxy group, A mercapto group etc. are mentioned. Among them, a halogen atom, an alkoxy group, an alkenyloxy group and an acyloxy group are preferable because of high activity, and an alkoxy group such as a methoxy group and an ethoxy group is more preferable because of its mild hydrolyzability and easy handling. An ethoxy group is more preferable. From the viewpoint of safety, an ethoxy group and an isopropenoxy group, in which the compounds eliminated by the reaction are ethanol and acetone, respectively, are preferable.

The hydroxy group or the hydrolyzable group can be bonded in the range of 1 to 3 to one silicon atom. When two or more of the hydroxy groups or the hydrolyzable groups are bonded to one silicon atom, these groups may be the same or different.

A in formula (2) is preferably 2 or 3, and particularly preferably 3, from the viewpoint of curability. From the viewpoint of storage stability, a is preferably 2.

R ¹ in the above formula (2) is, for example, an alkyl group such as a methyl group or an ethyl group, a cycloalkyl group such as a cyclohexyl group, an aryl group such as a phenyl group, an aralkyl group such as a benzyl group, or a trimethylsiloxy group. Chloromethyl group, methoxymethyl group and the like. Of these, a methyl group is preferable.

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 Group, (ethoxymethyl) dimethoxysilyl group, (1-methoxyethyl) dimethoxysilyl group, (aminomethyl) dimethoxysilyl group, (N, N-dimethylaminomethyl) dimethoxysilyl group, (N, N-diethylaminomethyl) dimethoxy Silyl group, (N N- diethylaminomethyl) diethoxysilyl group, (N- (2-aminoethyl) aminomethyl) dimethoxy silyl group, (acetoxymethyl) dimethoxy silyl group, and (acetoxymethyl) diethoxysilyl group.

Examples of the hydrolyzable silyl group-containing resin include a hydrolyzable silyl group-containing (meth) acrylic resin, a molecular chain terminal or an organic polymer having a hydrolyzable silyl group at the molecular chain terminal site, and a 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 hydrolyzable silyl group-containing (meth) acrylic acid ester and (meth) acrylic acid alkyl ester in the main chain.

Examples of the hydrolyzable silyl group-containing (meth) acrylic acid ester include 3- (trimethoxysilyl) propyl (meth) acrylate, 3- (triethoxysilyl) propyl (meth) acrylate, and (meth) acrylic. 3- (methyldimethoxysilyl) propyl acid, 2- (trimethoxysilyl) ethyl (meth) acrylate, 2- (triethoxysilyl) ethyl (meth) acrylate, 2- (methyldimethoxysilyl) (meth) acrylate Examples thereof include ethyl, trimethoxysilylmethyl (meth) acrylate, triethoxysilylmethyl (meth) acrylate, methyl (meth) acrylate (methyldimethoxysilyl), and the like.

Examples of the (meth) acrylic acid alkyl ester include methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, isopropyl (meth) acrylate, and n- (meth) acrylate. Butyl, isobutyl (meth) acrylate, tert-butyl (meth) acrylate, n-pentyl (meth) acrylate, n-hexyl (meth) acrylate, cyclohexyl (meth) acrylate, n- (meth) acrylate Heptyl, n-octyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, n-nonyl (meth) acrylate, n-decyl (meth) acrylate, n-dodecyl (meth) acrylate, (meth) Examples include stearyl acrylate.

As a method for producing the hydrolyzable silyl group-containing (meth) acrylic resin, specifically, for example, a hydrolyzable silicon group-containing (meth) acrylic acid ester system described in International Publication No. 2016/035718 Examples include a polymer synthesis method.

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 least at either the end of the main chain or the end of the side chain.
The backbone structure of the main chain is not particularly limited, and examples thereof include saturated hydrocarbon polymers, polyoxyalkylene polymers, (meth) acrylic acid ester polymers, and the like.

Examples of the polyoxyalkylene polymer include polyoxyethylene structure, polyoxypropylene structure, polyoxybutylene structure, polyoxytetramethylene structure, polyoxyethylene-polyoxypropylene copolymer structure, polyoxypropylene-poly Examples include polymers having an oxybutylene copolymer structure.

As a method for producing the organic polymer having a hydrolyzable silyl group at the molecular chain terminal or the molecular chain terminal part, specifically, for example, as described in International Publication No. 2016/035718, Examples thereof include a method for synthesizing an organic polymer having a crosslinkable silyl group only at a molecular chain terminal site. In addition, as another method for producing an organic polymer having a hydrolyzable silyl group at the molecular chain terminal or molecular chain terminal part, for example, a reactive silicon group-containing compound described in International Publication No. 2012/117902 Examples include a method for synthesizing a polyoxyalkylene polymer.

As a method for producing the hydrolyzable silyl group-containing polyurethane resin, for example, when a polyurethane resin is produced by reacting a polyol compound and a polyisocyanate compound, a silyl group-containing compound such as a silane coupling agent is further added. The method of making it react is mentioned. Specific examples include a method for synthesizing a urethane oligomer having a hydrolyzable silyl group described in JP-A-2017-48345.

Examples of the silane coupling agent include vinyltrichlorosilane, vinyltriethoxysilane, vinyltris (β-methoxy-ethoxy) silane, β- (3,4-epoxycyclohexyl) -ethyltrimethoxysilane, and γ-glycidoxy. Propyltrimethoxysilane, 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-isocyanatopropyl Trimethoxysilane, 3-isocyanate propyl triethoxysilane, and the like. Of these, γ-mercaptopropyltrimethoxysilane, 3-isocyanatopropyltrimethoxysilane, and 3-isocyanatopropyltriethoxysilane are preferable. These silane coupling agents may be used alone or in combination of two or more.

Furthermore, the moisture curable resin may have a radical polymerizable functional group.
The radical polymerizable functional group that the moisture curable resin may have is preferably a group having an unsaturated double bond, and more preferably a (meth) acryloyl group from the viewpoint of reactivity.
The moisture curable resin having a radical polymerizable functional group is not included in the radical polymerizable compound described later, and is treated as a moisture curable resin.

The weight average molecular weight of the moisture curable resin is not particularly limited, but a preferable lower limit is 800 and a preferable upper limit is 10,000. When the weight-average molecular weight of the moisture curable resin is within this range, the resulting adhesive composition has excellent flexibility without excessively high crosslinking density upon curing, and also has excellent coating properties. . The more preferable lower limit of the weight average molecular weight of the moisture curable resin is 2000, the more preferable upper limit is 8000, the still more preferable lower limit is 2500, and the further preferable upper limit is 6000.
In addition, the said weight average molecular weight is a value calculated | required by polystyrene conversion by measuring with a gel permeation chromatography (GPC) in this specification. Examples of the column for measuring the weight average molecular weight in terms of polystyrene by GPC include Shodex LF-804 (manufactured by Showa Denko KK). Moreover, tetrahydrofuran etc. are mentioned as a solvent used by GPC.

The preferable lower limit of the content of the moisture curable resin in 100 parts by weight of the adhesive composition of the present invention is 20 parts by weight, and the preferable upper limit is 90 parts by weight. When the content of the moisture curable resin is within this range, the resulting adhesive composition is more excellent in moisture curability while maintaining excellent weather resistance and flexibility of the cured product. The minimum with more preferable content of the said moisture curable resin is 30 weight part, and a more preferable upper limit is 70 weight part.

In order to further improve the effect of achieving both adhesiveness and reworkability, the present inventors aim to increase the amount of wax per unit area that is in contact with the adherend, so that The thickness of the adhesive layer containing the agent composition was studied. FIG. 1 is a schematic view showing the adhesion state of an adherend by the adhesive composition of the present invention when (a) the thickness of the adhesive layer is small and (b) large.
As shown in FIG. 1, the greater the thickness 3 of the adhesive layer made of the adhesive composition 2 that adheres the adherend 1, the greater the amount of wax 5 present in the adhesive composition 2 per unit area 4. Become. Therefore, the effect which makes adhesiveness and rework property compatible is improved more by making the thickness 3 of the contact bonding layer into the thickness as large as the adhesiveness can be maintained. In this case, in order to maintain the thickness 3 of the adhesive layer, it is preferable to perform photocuring as a pretreatment. Therefore, in order to develop photocurability, the adhesive composition of the present invention preferably contains a radical polymerizable compound and a photo radical polymerization initiator. That is, by containing the radically polymerizable compound and the photoradical polymerization initiator, photocurability and moisture curability are ensured, and both cohesion and reworkability are more effective. Such an adhesive composition of the present invention can be suitably used especially for an adhesive used for a sealant for a display element or a case connection of a narrow frame design.

The radical polymerizable compound is not particularly limited as long as it is a radical polymerizable compound having photopolymerizability and is a compound having a radical polymerizable functional group in the molecule. Among them, a compound having an unsaturated double bond as a radical polymerizable functional group is suitable, and a compound having a (meth) acryloyl group (hereinafter also referred to as “(meth) acrylic compound”) is particularly preferable from the viewpoint of reactivity. Is preferred.
In the present specification, the “(meth) acryloyl” means acryloyl or methacryloyl, and the “(meth) acryl” means acryl or methacryl.

Examples of the (meth) acrylic compound include (meth) acrylic acid ester compounds, epoxy (meth) acrylates, urethane (meth) acrylates, and the like.
In the present specification, the “(meth) acrylate” means acrylate or methacrylate. Moreover, the said urethane (meth) acrylate does not have a residual isocyanate group.

Examples of monofunctional compounds among the (meth) acrylic acid ester compounds include phthalimide acrylates such as N-acryloyloxyethyl hexahydrophthalimide, various imide (meth) acrylates, methyl (meth) acrylate, and 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, isomyristyl (meth) acrylate, stearyl (meth) acrylate, cyclohexyl (meth) acrylate Rate, isobornyl (meth) acrylate, dicyclopentenyl (meth) acrylate, benzyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, 4 -Hydroxybutyl (meth) acrylate, 2-methoxyethyl (meth) acrylate, 2-ethoxyethyl (meth) acrylate, 2-butoxyethyl (meth) acrylate, methoxyethylene glycol (meth) acrylate, methoxypolyethylene glycol (meth) acrylate , Ethyl carbitol (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, 2-phenoxyethyl (meth) acrylate, phenoxydiethylene glycol (meta Acrylate, phenoxypolyethylene glycol (meth) acrylate, 2,2,2-trifluoroethyl (meth) acrylate, 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) Examples include acryloyloxyethyl-2-hydroxypropyl phthalate, glycidyl (meth) acrylate, 2- (meth) acryloyloxyethyl phosphate, and the like.

Examples of the bifunctional compound among the (meth) acrylic acid ester compounds include 1,3-butanediol di (meth) acrylate, 1,4-butanediol di (meth) acrylate, and 1,6-hexane. Diol 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, poly Lopylene glycol di (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 isocyanuric acid 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, polybutadiene diol (Meth) acrylate.

Further, among the above (meth) acrylic acid ester compounds, those having three or more functions include, for example, 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, glycerol tri (meth) acrylate, propylene oxide-added glycerol tri (meth) acrylate, Tris (meth) acryloyloxyethyl phosphate, ditrimethylolpropane tetra (meth) acrylate, pentaerythritol tetra Meth) acrylate, dipentaerythritol penta (meth) acrylate, dipentaerythritol hexa (meth) acrylate.

Examples of the epoxy (meth) acrylate include those obtained by reacting an epoxy compound and (meth) acrylic acid in the presence of a basic catalyst according to a conventional method.

Examples of the epoxy compound as a raw material for synthesizing the epoxy (meth) acrylate include bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, and 2,2′-diallyl bisphenol 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 epoxy resin, orthocresol novolac epoxy resin, dicyclopentadiene novolac epoxy resin, biphenyl novolac epoxy resin, naphtha Ren phenol novolak type epoxy resin, glycidyl amine type epoxy resin, alkyl polyol type epoxy resin, rubber modified epoxy resin, glycidyl ester compounds, bisphenol A type episulfide resins.

Examples of commercially available epoxy (meth) acrylates include EBECRYL860, EBECRYL3200, EBECRYL3201, EBECRYL3412, EBECRYL3600, EBECRYL3700, EBECRYL3701, EBECRYL3702, EBECRY370R ), EA-1010, EA-1020, EA-5323, EA-5520, EA-CHD, EMA-1020 (all manufactured by Shin-Nakamura Chemical Co., Ltd.), epoxy ester M-600A, epoxy ester 40EM, epoxy ester 70PA, Epoxy ester 200PA, Epoxy ester 80MF 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 And Denacol acrylate DA-911 (all manufactured by Nagase ChemteX Corporation).

The urethane (meth) acrylate can be obtained, for example, by reacting a (meth) acrylic acid derivative having a hydroxyl group with an isocyanate compound in the presence of a catalytic amount of a tin-based compound.

Examples of the isocyanate compound include 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, tolidine diisocyanate, xylylene diisocyanate (XDI), hydrogenated XDI, lysine diisocyanate, triphenylmethane triisocyanate, tris (isocyanatophenyl) thiophosphate, tetramethylxylylene diene Isocyanate, 1,6,11-undecane triisocyanate and the like.

As the isocyanate compound, a chain-extended isocyanate compound obtained by a reaction between a polyol and an excess of an isocyanate compound can also be used.
Examples of the polyol include ethylene glycol, propylene glycol, glycerin, sorbitol, trimethylolpropane, carbonate diol, polyether diol, polyester diol, and polycaprolactone diol.

Examples of the (meth) acrylic acid derivative having a hydroxyl group include divalent alcohols such as ethylene glycol, propylene glycol, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, and polyethylene glycol. Mono (meth) acrylates, mono (meth) acrylates or di (meth) acrylates of trivalent alcohols such as trimethylolethane, trimethylolpropane, and glycerin, and epoxy (meth) acrylates such as bisphenol A type epoxy (meth) acrylates ) Acrylate and the like.

Examples of commercially available urethane (meth) acrylates include M-1100, M-1200, M-1210, M-1600 (all manufactured by Toagosei Co., Ltd.), EBECRYL230, EBECRYL270, EBECRYL4858, EBECRYL8402, EBECRYL8411, EBECRYL8412, EBECRYL8413, EBECRYL8804, EBECRYL8803, EBECRYL8807, EBECRYL9260, EBECRYL1290, EBECRYL5129, EBECRYL4842, EBECRYL210, EBECRYL4827, EBECRYL6700, EBECRYL220, EBECRYL2220, KRM7735, KRM-8295 (both manufactured by Daicel Orunekusu, Inc. ), 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 are manufactured by Negami Kogyo Co., Ltd.), 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, UA-W2A (all Shin-Nakamura Manabu Industries, Ltd.), AI-600, AH-600, AT-600, UA-101I, UA-101T, UA-306H, UA-306I, UA-306T (all manufactured by Kyoeisha Chemical Co., Ltd.).

In addition, other radical polymerizable compounds other than those described above can be used as appropriate.
Examples of the other radical polymerizable compounds include N, N-dimethyl (meth) acrylamide, N- (meth) acryloylmorpholine, N-hydroxyethyl (meth) acrylamide, N, N-diethyl (meth) acrylamide, N -(Meth) acrylamide compounds such as isopropyl (meth) acrylamide, N, N-dimethylaminopropyl (meth) acrylamide, styrene, α-methylstyrene, N-vinyl-2-pyrrolidone, N-vinyl-ε-caprolactam, etc. A vinyl compound etc. are mentioned.

The radical polymerizable compound preferably contains a monofunctional radical polymerizable compound and a polyfunctional radical polymerizable compound from the viewpoint of adjusting curability. By containing the monofunctional radical polymerizable compound and the polyfunctional radical polymerizable compound, the resulting adhesive composition is more excellent in curability and tackiness. Of these, urethane (meth) acrylate is preferably used in combination with the monofunctional radical polymerizable compound as the polyfunctional radical polymerizable compound. The polyfunctional radically polymerizable compound is preferably bifunctional or trifunctional, and more preferably bifunctional.

When the radical polymerizable compound contains the monofunctional radical polymerizable compound and the polyfunctional radical polymerizable compound, the content of the polyfunctional radical polymerizable compound is the same as the monofunctional radical polymerizable compound and the polyfunctional radical polymerizable compound. A preferable lower limit is 2 parts by weight and a preferable upper limit is 45 parts by weight with respect to a total of 100 parts by weight with the functional radical polymerizable compound. When the content of the polyfunctional radically polymerizable compound is within this range, the resulting adhesive composition is more excellent in curability and tackiness. The minimum with more preferable content of the said polyfunctional radically polymerizable compound is 5 weight part, and a more preferable upper limit is 35 weight part.

The preferable lower limit of the content of the radical polymerizable compound in 100 parts by weight of the adhesive composition of the present invention is 10 parts by weight, and the preferable upper limit is 80 parts by weight. When the content of the radical polymerizable compound is within this range, the resulting adhesive composition is excellent in both photocurability and moisture curability. The minimum with more preferable content of the said radically polymerizable compound is 30 weight part, and a more preferable upper limit is 60 weight part.

Examples of the photo radical polymerization initiator include benzophenone compounds, acetophenone compounds, acylphosphine oxide compounds, titanocene compounds, oxime ester compounds, benzoin ether compounds, thioxanthones, and the like.

Examples of commercially available photo radical polymerization initiators include IRGACURE 184, IRGACURE 369, IRGACURE 379, IRGACURE 651, IRGACURE 784, IRGACURE 819, IRGACURE 907, IRGACURE 2959, IRGACURE OXE01, and Benzylin TPO, all manufactured by BALGIN SPO. Benzoin ethyl ether, benzoin isopropyl ether (both manufactured by Tokyo Chemical Industry Co., Ltd.) and the like.

The content of the photo radical polymerization initiator is preferably 0.01 parts by weight and preferably 10 parts by weight with respect to 100 parts by weight of the radical polymerizable compound. When the content of the photo radical polymerization initiator is within this range, the resulting adhesive composition is more excellent in photocurability and storage stability. The minimum with more preferable content of the said radical photopolymerization initiator is 0.1 weight part, and a more preferable upper limit is 5 weight part.

The adhesive composition of the present invention preferably contains a filler.
By containing the filler, the adhesive composition of the present invention has suitable thixotropy and can sufficiently retain the shape after coating.

The filler preferably has a primary particle diameter with a preferred lower limit of 1 nm and a preferred upper limit of 50 nm. When the primary particle diameter of the filler is within this range, the resulting adhesive composition is more excellent in applicability and shape retention after application. The more preferable lower limit of the primary particle diameter of the filler is 5 nm, the more preferable upper limit is 30 nm, the still more preferable lower limit is 10 nm, and the still more preferable upper limit is 20 nm.
The primary particle size of the filler can be measured by dispersing the filler in a solvent (water, organic solvent, etc.) using NICOMP 380ZLS (manufactured by PARTICS SIZING SYSTEMS).
Further, the filler may be present as secondary particles (a collection of a plurality of primary particles) in the adhesive composition of the present invention, and the preferred lower limit of the particle diameter of such secondary particles is 5 nm, A preferable upper limit is 500 nm, a more preferable lower limit is 10 nm, and a more preferable upper limit is 100 nm. The particle diameter of the secondary particles of the filler can be measured by observing the adhesive composition of the present invention or a cured product thereof using a transmission electron microscope (TEM).

As the filler, an inorganic filler is preferable, and examples thereof include silica, talc, titanium oxide, zinc oxide, calcium carbonate and the like. Among these, silica is preferable because the resulting adhesive composition is excellent in ultraviolet transmittance. These fillers may be used alone or in combination of two or more.

The filler is preferably subjected to a hydrophobic surface treatment. By the hydrophobic surface treatment, the resulting adhesive composition is more excellent in shape retention after application.
Examples of the hydrophobic surface treatment include silylation treatment, alkylation treatment, and epoxidation treatment. Especially, since it is excellent in the effect which improves shape retainability, a silylation process is preferable and a trimethylsilylation process is more preferable.

Examples of the method for treating the filler with a hydrophobic surface include a method for treating the surface of the filler with a surface treatment agent such as a silane coupling agent.
Specifically, for example, the trimethylsilylated silica is prepared by synthesizing silica by a method such as a sol-gel method and spraying hexamethyldisilazane in a state where the silica is fluidized, or in an organic solvent such as alcohol or toluene. After adding silica, hexamethyldisilazane, and water, it can be produced by a method of evaporating and drying water and an organic solvent with an evaporator.

The preferable lower limit of the content of the filler in 100 parts by weight of the adhesive composition of the present invention is 1 part by weight, and the preferable upper limit is 20 parts by weight. When the content of the filler is within this range, the obtained adhesive composition is more excellent in applicability and shape retention after application. The more preferred lower limit of the content of the filler is 2 parts by weight, the more preferred upper limit is 15 parts by weight, the still more preferred lower limit is 3 parts by weight, the still more preferred upper limit is 10 parts by weight, and the particularly preferred lower limit is 4 parts by weight. .

The adhesive composition of the present invention may contain a light shielding agent.
By containing the said light-shielding agent, the adhesive composition of this invention becomes the thing excellent in light-shielding property, For example, when it uses for a display element, it can prevent light leakage. In addition, the display device manufactured using the adhesive composition of the present invention blended with the above light-shielding agent has a high contrast without leaking light, because the adhesive composition has sufficient light-shielding properties, and excellent Image display quality.
In the present specification, the “light-shielding agent” means a material having an ability of hardly transmitting light in the visible light region.

Examples of the light-shielding agent include iron oxide, titanium black, aniline black, cyanine black, fullerene, carbon black, and resin-coated carbon black. Further, the light-shielding agent does not have to be black, and materials such as silica, talc, titanium oxide, and the like mentioned as fillers can be used as long as they have the ability to hardly transmit light in the visible light region. Included in the light shielding agent. Of these, titanium black is preferable.

Titanium black is a substance having a higher transmittance in the vicinity of the ultraviolet region, particularly for light having a wavelength of 370 to 450 nm, compared to the average transmittance for light having a wavelength of 300 to 800 nm.
That is, the above-described titanium black sufficiently shields light having a wavelength in the visible light region, thereby providing light shielding properties to the adhesive composition of the present invention, while having a property of transmitting light having a wavelength in the vicinity of the ultraviolet region. It is an agent. Therefore, the photo-curing property of the adhesive composition of the present invention can be improved by using a photo-radical polymerization initiator that can initiate a reaction with light having a wavelength (370 to 450 nm) that increases the transmittance of the titanium black. Can be increased. On the other hand, the light shielding agent contained in the adhesive composition of the present invention is preferably a highly insulating material, and titanium black is also suitable as the highly insulating light shielding agent.
The titanium black preferably has an optical density (OD value) of 3 or more, and more preferably 4 or more. The titanium black preferably has a blackness (L value) of 9 or more, more preferably 11 or more. The higher the light shielding property of the titanium black, the better. There is no particular upper limit to the OD value of the titanium black, but it is usually 5 or less.

The above-mentioned titanium black exhibits a sufficient effect even if it is not surface-treated, but the surface is treated with an organic component such as a coupling agent, silicon oxide, titanium oxide, germanium oxide, aluminum oxide, zirconium oxide Surface-treated titanium black such as those coated with an inorganic component such as magnesium oxide can also be used. Especially, what is processed with the organic component is preferable at the point which can improve insulation more.

Examples of commercially available titanium black include 12S, 13M, 13M-C, 13R-N (all manufactured by Mitsubishi Materials Corporation), Tilak D (manufactured by Ako Kasei Co., Ltd.), and the like.

The preferable lower limit of the specific surface area of the titanium black is 5 m ² / g, the preferable upper limit is 40 m ² / g, the more preferable lower limit is 10 m ² / g, and the more preferable upper limit is 25 m ² / g.
Moreover, the preferable lower limit of the sheet resistance of the titanium black is 10 ⁹ Ω / □ when mixed with a resin (70% blending), and the more preferable lower limit is 10 ¹¹ Ω / □.

In the adhesive composition of the present invention, the primary particle diameter of the light-shielding agent is appropriately selected depending on the application, such as the distance between the substrates of the display element or the like, but a preferred lower limit is 30 nm and a preferred upper limit is 500 nm. When the primary particle diameter of the light-shielding agent is within this range, the resulting adhesive composition is excellent in applicability to the substrate and workability without greatly increasing viscosity and thixotropy. The more preferable lower limit of the primary particle diameter of the light shielding agent is 50 nm, and the more preferable upper limit is 200 nm.
The primary particle diameter of the light shielding agent can be measured in the same manner as the primary particle diameter of the filler.

The minimum with preferable content of the said light-shielding agent in 100 weight part of adhesive compositions of this invention is 0.05 weight part, and a preferable upper limit is 10 weight part. When the content of the light-shielding agent is within this range, the obtained adhesive composition is superior in light-shielding properties while maintaining excellent drawing properties, adhesion to a substrate, and strength after curing. Become. The more preferable lower limit of the content of the light shielding agent is 0.1 parts by weight, the more preferable upper limit is 2 parts by weight, and the still more preferable upper limit is 1 part by weight.

The adhesive composition of the present invention may further contain additives such as a colorant, an ionic liquid, a solvent, metal-containing particles, and a reactive diluent as necessary.

As a method for producing the adhesive composition of the present invention, for example, using a mixer such as a homodisper, a homomixer, a universal mixer, a planetary mixer, a kneader, a three roll, a moisture curable resin, a wax, And a method of mixing a radically polymerizable compound and a radical photopolymerization initiator and additives to be added as necessary.

The adhesive composition of the present invention preferably has a water content of 100 ppm or less. When the water content is 100 ppm or less, the reaction between the moisture curable resin and water during storage can be suppressed, and the adhesive composition is more excellent in storage stability. The water content is more preferably 80 ppm or less.
The water content can be measured by a Karl Fischer moisture measuring device.

In the adhesive composition of the present invention, the preferable lower limit of the viscosity measured at 25 ° C. and 1 rpm using a cone plate viscometer is 50 Pa · s, and the preferable upper limit is 1000 Pa · s. When the viscosity is within this range, the workability when the adhesive composition is applied to an adherend such as a substrate is improved. A more preferable lower limit of the viscosity is 80 Pa · s, a more preferable upper limit is 500 Pa · s, and a still more preferable upper limit is 400 Pa · s.
In addition, when the viscosity of the adhesive composition of this invention is too high, applicability | paintability can be improved by heating at the time of application | coating.

The preferable lower limit of the thixotropic index of the adhesive composition of the present invention is 1.3, and the preferable upper limit is 5.0. When the thixotropic index is within this range, the workability when the adhesive composition is applied to an adherend such as a substrate is improved. The more preferable lower limit of the thixotropic index is 1.5, and the more preferable upper limit is 4.0.
In the present specification, the thixotropic index is a viscosity measured at 25 ° C. and 1 rpm using a cone plate viscometer, and measured at 25 ° C. and 10 rpm using a cone plate viscometer. It means the value divided by the viscosity.

In the adhesive composition of the present invention, the optical density (OD value) of a cured product having a thickness of 1 mm after curing is preferably 1 or more. When the OD value is 1 or more, the light shielding property is excellent, and when used in a display element, leakage of light can be prevented and high contrast can be obtained. The OD value is more preferably 1.5 or more.
The higher the OD value, the better. However, if too much light-shielding agent is blended to increase the OD value, workability will decrease due to thickening, so that it balances the blending amount of the light-shielding agent. The preferable upper limit of the OD value of the cured product is 4.
In addition, the OD value after hardening of the said adhesive composition can be measured using an optical densitometer.

The adhesive composition of the present invention can be easily peeled off by heating during rework after curing.
The preferable lower limit of the heating temperature during the rework is 60 ° C., and the preferable upper limit is 120 ° C. When the heating temperature is within this range, the peeling can be easily performed without damaging the electronic component or the like. A more preferable lower limit of the heating temperature during the rework is 75 ° C., and a more preferable upper limit is 110 ° C.

The cured product of the adhesive composition of the present invention is also one aspect of the present invention.
When the moisture-curable urethane resin is contained in the adhesive composition of the present invention before curing, the cured body of the present invention has a urea bond and / or a urethane bond. The component contained in the cured product of the present invention is a component contained in the adhesive composition of the present invention and a component that has been changed by a chemical reaction or the like when the adhesive composition of the present invention is cured.

The cured product of the present invention is suitable when the wax is present in the cured product in the above-described wax fine particles because the contact area between the resin and the wax is increased and the reworkability is improved.
The smaller the particle diameter of the wax fine particles in the cured body, the better. The preferred upper limit is 300 μm. When the particle diameter of the wax fine particles is 300 μm or less, the reworkability is improved. A more preferable upper limit of the particle diameter of the wax fine particles in the cured body is 250 μm, a further preferable upper limit is 100 μm, a still more preferable upper limit is 50 μm, and a particularly preferable upper limit is 10 μm.
The preferred lower limit of the particle diameter of the wax fine particles in the cured product is not particularly limited, but the substantial lower limit is 0.1 μm.
In addition, the particle diameter of the wax fine particles in the cured body can be measured by observing the cut surface of the cured body using a scanning electron microscope, a transmission electron microscope, a laser microscope, or the like. As a preferable measurement method, a cross section of the cured body is exposed using a cryomicrotome, the cross section is observed using a scanning electron microscope, the particle diameter of 50 randomly selected particles is measured, and an average value is obtained. The method of calculating is mentioned.

The cured product of the present invention has a storage elastic modulus change rate ((high temperature side storage elastic modulus) / (low temperature side storage elastic modulus)) of temperatures of 60 ° C. or higher and 130 ° C. or lower. It is preferable that the change rate of the storage elastic modulus in is 0.6 or less. When the rate of change in the storage elastic modulus is 0.6 or less, the cured product of the present invention is excellent in adhesion stability at the time of adhesion, and has an excellent rework workability because the adhesive force is reduced at the time of rework. A more preferable upper limit of the change rate of the storage elastic modulus is 0.55, and a more preferable upper limit is 0.45.

The cured body of the present invention has an energy amount per unit time at the peak top of the endotherm of the cured body in differential scanning calorimetry A, an energy amount per unit time of the moisture curable resin at the measurement temperature of A, When the amount of energy per unit time of the wax at the measurement temperature of A is C and the content of the wax in the cured product is X wt%, it is preferable that the following formula is satisfied.
(AB) / (C × X / 100) ≧ 50
By satisfy | filling the said Formula, the hardening body of this invention will be excellent by rework property.
A more preferred lower limit of (AB) / (C × X / 100) is 60, and a more preferred lower limit is 70.

An electronic component having a cured product of the adhesive composition of the present invention is also one aspect of the present invention. The adhesive composition of the present invention has the excellent effects described above, particularly in electronic parts that require downsizing. In the electronic component of the present invention, the adhesive composition of the present invention is mainly used for bonding adherends.

Examples of adherends that can be bonded using the adhesive composition of the present invention include various adherends such as metal, glass, and plastic.
Examples of the shape of the adherend include a film shape, a sheet shape, a plate shape, a panel shape, a tray shape, a rod (rod-like body) shape, a box shape, and a housing shape.

Examples of the metal include steel, stainless steel, aluminum, copper, nickel, chromium, and alloys thereof.
Examples of the glass include alkali glass, non-alkali glass, and quartz glass.
Examples of the plastic include polyolefin resins such as high density polyethylene, ultra high molecular weight polyethylene, isotactic polypropylene, syndiotactic polypropylene, and ethylene propylene copolymer resin, nylon 6 (N6), nylon 66 (N66), Nylon 46 (N46), Nylon 11 (N11), Nylon 12 (N12), Nylon 610 (N610), Nylon 612 (N612), Nylon 6/66 copolymer (N6 / 66), Nylon 6/66/610 Polymer (N6 / 66/610), nylon MXD6 (MXD6), nylon 6T, nylon 6 / 6T copolymer, nylon 66 / PP copolymer, polyamide 66 resin such as nylon 66 / PPS copolymer, polybutylene Terephthalate (PBT), polyethylene Rephthalate (PET), polyethylene isophthalate (PEI), PET / PEI copolymer, polyarylate (PAR), polybutylene naphthalate (PBN), liquid crystal polyester, polyoxyalkylene diimide diacid / polybutylene terephthalate copolymer, etc. Aromatic polyester resins, polyacrylonitrile (PAN), polymethacrylonitrile, acrylonitrile / styrene copolymer (AS), methacrylonitrile / styrene copolymer, polynitrile such as methacrylonitrile / styrene / butadiene copolymer Resin, polycarbonate, polymethacrylate resin such as polymethyl methacrylate (PMMA), polyethyl methacrylate, ethylene / vinyl acetate copolymer (EVA), polyvinyl alcohol (PVA), vinyl alcohol And polyvinyl resins such as vinyl / ethylene copolymer (EVOH), polyvinylidene chloride (PVDC), polyvinyl chloride (PVC), vinyl chloride / vinylidene chloride copolymer, vinylidene chloride / methyl acrylate copolymer, and the like. .

Examples of the adherend include a composite material having a metal plating layer on the surface, and examples of the base material for plating the composite material include the metal, glass, and plastic described above.
Furthermore, examples of the adherend include materials in which a passivation film is formed by passivating a metal surface. Examples of the passivating treatment include heat treatment and anodizing treatment. . In particular, in the case of an aluminum alloy or the like whose material is an international aluminum alloy name in the 6000 series, the adhesiveness can be improved by performing a sulfuric acid alumite treatment or a phosphoric acid alumite treatment as the passivation treatment.

In addition, the first substrate, the second substrate, and a cured product of the adhesive composition of the present invention are included, and at least a part of the first substrate includes at least a part of the second substrate and the above-described second substrate. An assembly part joined through a cured body of the adhesive composition is also one aspect of the present invention.
The first substrate and the second substrate each preferably include at least one electronic component.

ADVANTAGE OF THE INVENTION According to this invention, the adhesive composition which is excellent in adhesiveness and can be easily reworked at low temperature can be provided. Moreover, according to this invention, the electronic component and assembly component which have the hardening body of this adhesive composition, and the hardening body of this adhesive composition can be provided.

(A) It is a schematic diagram which shows the adhesion state of the to-be-adhered body by the adhesive composition of this invention in case the thickness of an adhesive layer is small and (b) large. (A) is a schematic diagram which shows the case where the sample for rework property evaluation is seen from the top, (b) is a schematic diagram which shows the case where the sample for rework property evaluation is seen from the side.

Hereinafter, the present invention will be described in more detail with reference to examples. However, the present invention is not limited to these examples.

(Synthesis example 1 (production of moisture-curing urethane resin))
As a polyol compound, 100 parts by weight of polytetramethylene ether glycol (manufactured by Mitsubishi Chemical Corporation, “PTMG-2000”) and 0.01 part by weight of dibutyltin dilaurate were placed in a 500-mL separable flask and subjected to vacuum (20 mmHg The following was stirred for 30 minutes at 100 ° C. and mixed. After that, normal pressure was applied and 26.5 parts by weight of diphenylmethane diisocyanate (manufactured by Nisso Shoji Co., Ltd., “Pure MDI”) was added as a polyisocyanate compound. Molecular weight 2700) was obtained.

(Examples 1 to 6, Comparative Example 1)
In accordance with the blending ratio described in Table 1, each material was stirred with a planetary stirrer (“Shinky Co., Ltd.,“ Awatori Netaro ”), and then uniformly mixed with a ceramic three roll. To 6 and Comparative Example 1 were obtained.

<Evaluation>
The following evaluation was performed about each adhesive composition obtained by the Example and the comparative example. The results are shown in Table 1.

(Reworkability)
Each adhesive composition obtained in Examples and Comparative Examples was applied to a polycarbonate substrate with a width of about 2 mm using a dispensing apparatus. Thereafter, UV-LED (wavelength 365 nm) is used to irradiate the adhesive composition with ultraviolet rays of 1000 mJ / cm ² , a glass plate is bonded to the polycarbonate substrate, a weight of 20 g is placed, and it is allowed to stand overnight to cure moisture. Thus, a sample for evaluating reworkability was obtained.
FIG. 2 is a schematic diagram showing the reworkability evaluation sample as viewed from above (FIG. 2A), and a schematic diagram showing the reworkability evaluation sample as viewed from the side (FIG. 2B). showed that.
The prepared sample for reworkability evaluation was pulled at a rate of 5 mm / sec in the shearing direction using a tensile tester (manufactured by Shimadzu Corporation, “Ez-Graph”) at 25 ° C. and 100 ° C., and a polycarbonate substrate and a glass plate The strength (adhesion strength) at the time of peeling was measured. As a result, when the ratio of the adhesive strength at 100 ° C. to the adhesive strength at 25 ° C. ((adhesive strength at 100 ° C.) / (Adhesive strength at 25 ° C.)) was 0.3 or less, “◎” Rework as 0.3 when 0.5 and less than “○”, when 0.5 and 0.7 or less as “△”, and when 0.7 is exceeded as “×” Sex was evaluated.

(Change rate of storage modulus)
Each adhesive composition obtained in Examples and Comparative Examples was poured into a Teflon (registered trademark) mold having a width of 3 mm, a length of 30 mm, and a thickness of 1 mm, and ultraviolet rays were 1000 mJ / mm using a UV-LED (wavelength 365 nm). After photocuring by irradiating cm ^2, it was cured by moisture by leaving it for 3 days to obtain a cured product.
Using the dynamic viscoelasticity measuring device (“DVA-200” manufactured by IT Measurement Control Co., Ltd.), the obtained cured product was subjected to deformation mode: tensile, set strain: 1%, measurement frequency: 1 Hz, temperature increase rate: The dynamic viscoelasticity was measured in the range of 40 ° C. to 150 ° C. under the condition of 5 ° C./min, and the storage elastic modulus at each temperature was determined. About the obtained storage elastic modulus, the change rate of this storage elastic modulus in the temperature interval of 10 degreeC with the largest variation | change_quantity of storage elastic modulus among the temperatures of 60 degreeC or more and 130 degrees C or less was computed by the following formula.
Change rate of storage elastic modulus = (storage elastic modulus on high temperature side) / (storage elastic modulus on low temperature side)

(Influence of wax on calorimetry)
A differential scanning calorimeter (TA Instruments Co., Ltd.) was used for the cured product of each adhesive composition obtained in the same manner as in the above-mentioned “(change ratio of storage elastic modulus)” and the wax alone used in each adhesive composition. Manufactured by DSC Q100), and the change in heat quantity due to temperature change was measured. The amount of energy per unit time at the peak top of the endotherm of the cured product is A, the amount of energy per unit time of the moisture curable resin at the measurement temperature of A is B, and the amount of energy per unit time of the wax at the measurement temperature of A. The energy amount was C and the wax content in the cured product was X wt%, and the degree of influence of the wax on calorimetry was calculated by the following formula.
Effect of wax on calorimetry = (AB) / (C × X / 100)
In addition, the measurement of the said calorie | heat amount change was implemented on the following measurement conditions, and the obtained measured value was set to A, B, and C, respectively.
<Measurement conditions>
Atmosphere: Nitrogen (flow rate 40 mL / min)
Temperature increase rate: 10 ° C / min
Sample amount: 10mg
In addition, since the adhesive composition obtained in Comparative Example 1 does not contain wax, this evaluation was not performed.

ADVANTAGE OF THE INVENTION According to this invention, the adhesive composition which is excellent in adhesiveness and can be easily reworked at low temperature can be provided. Moreover, according to this invention, the electronic component and assembly component which have the hardening body of this adhesive composition, and the hardening body of this adhesive composition can be provided.

DESCRIPTION OF SYMBOLS 1 Adherent 2 Adhesive composition 3 Adhesive layer thickness 4 Unit area 5 Wax 6 Polycarbonate substrate 7 Adhesive composition 8 Glass plate

Claims (13)

1. An adhesive composition comprising a moisture curable resin and a wax.
2. The adhesive composition according to claim 1, wherein the wax has a melting point of 50 ° C. or higher and 140 ° C. or lower.
3. The adhesive composition according to claim 1 or 2, wherein the content of the wax in 100 parts by weight of the adhesive composition is 1 part by weight or more and 50 parts by weight or less.
4. The adhesive composition according to claim 1, wherein the wax is present in the adhesive composition as fine particles.
5. The adhesive composition according to claim 4, wherein a particle diameter of the fine particles is 300 μm or less.
6. The adhesive composition according to claim 1, wherein the moisture curable resin is a moisture curable urethane resin.
7. The adhesive composition according to claim 1, 2, 3, 4, 5 or 6, comprising a radical polymerizable compound and a photo radical polymerization initiator.
8. A cured product of the adhesive composition according to claim 4, 5, 6, or 7,
   A cured body, wherein a particle diameter of the fine particles in the cured body is 300 μm or less.
9. A cured product of the adhesive composition according to claim 1, 2, 3, 4, 5, 6 or 7,
   Change in storage elastic modulus at a temperature interval of 10 ° C. where the rate of change in storage elastic modulus ((storage elastic modulus on high temperature side) / (storage elastic modulus on low temperature side)) is the largest among the temperatures of 60 ° C. or higher and 130 ° C. or lower. A cured product having a ratio of 0.6 or less.
10. A cured product of the adhesive composition according to claim 1, 2, 3, 4, 5, 6 or 7,
    The amount of energy per unit time at the peak top of the endotherm of the cured product in differential scanning calorimetry is A, the amount of energy per unit time of the moisture curable resin at the measurement temperature of A is wax, and the wax at the measurement temperature of A When the energy amount per unit time of C is C and the wax content in the cured body is X wt%, the cured body satisfies the following formula.
    (AB) / (C × X / 100) ≧ 50
11. An electronic component comprising a cured product of the adhesive composition according to claim 1, 2, 3, 4, 5, 6 or 7.
12. A first substrate, a second substrate, and a cured product of the adhesive composition according to claim 1, 2, 3, 4, 5, 6 or 7,
    At least a part of the first substrate is joined to at least a part of the second substrate via a cured body of the adhesive composition.
13. 13. The assembly component according to claim 12, wherein each of the first substrate and the second substrate has at least one electronic component.

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