JP2021093422A - Encapsulating composition - Google Patents

Abstract

To provide an encapsulating composition which can maintain a high-adhesive force between adhered bodies even if it is used for the encapsulation of a hollow structure to be processed at a high temperature and has a high-humidity resistance.SOLUTION: An encapsulating composition of the present invention, contains: a (meth) acryl oligomer having (a-1): a bisphenol skeleton; and a (meth) acryl monomer having (a-2): a hydroxyl group, and contains (A): a radical curable resin, (B): a light radical polymerization initiator, and (C): a filler material (where a fumed silica is excluded) having at least one of the (a-1) component and the (a-2) component includes an acryloyl group.SELECTED DRAWING: None

Description

The present invention relates to a sealing composition containing a (meth) acrylic oligomer having a bisphenol skeleton, a (meth) acrylic monomer having a hydroxyl group, a photoradical polymerization initiator, and a filler.

Optical sensors such as camera image sensors and reading sensors are used by packaging semiconductors that integrate circuits. This package is a ceramic cavity that is a hollow structure in which a semiconductor is fixed in a cavity such as resin or ceramic, the upper part of the cavity is covered with glass or plastic, and the cavity and glass or plastic are bonded with a sealing composition. The type has been used conventionally.

As a sealing composition used for such a ceramic cavity type, a composition containing a urethane (meth) acrylate, a (meth) acrylic acid ester monomer, a photopolymerization initiator and a filler is known (for example, a patent). Reference 1).

On the other hand, in the assembly of optical sensors, solder reflow is increasingly performed when mounting on a substrate. This solder reflow reaches a high temperature of 240 to 260 ° C. At such a high temperature, the gas existing in the hollow portion expands, and floating or peeling may occur between the cavity and the glass or plastic.

As a sealing composition used for a ceramic cavity type that can be used for solder reflow, a composition containing an epoxy resin, a photocation initiator, a thermal cation initiator, and a specific filler is known (for example, Patent Document 2). reference).

Since the composition described in Patent Document 2 uses a cationically curable epoxy resin, the thick film curability was not sufficient.

If the cured product of the sealing composition between the cavity and the glass has high hygroscopicity, the moisture that has passed through the cured product becomes water droplets in the hollow portion of the package, which impairs the readability of the sensor. It has been confirmed that the composition of No. 2 has low hygroscopicity of the cured product of the sealing composition.

Japanese Unexamined Patent Publication No. 2001-163931 International Publication 2005/05/9002

However, recently, a chip size package type, which is a hollow structure in which glass or plastic is bonded to the outer periphery of a semiconductor with a sealing composition, has also been used. In the ceramic cavity type, the thickness of the cured product of the sealing composition is about 20 μm, whereas in the chip size package type, the thickness of the cured product of the sealing composition is about 150 μm. The cured product makes it easier for moisture to pass through. Therefore, the chip size package type is required to have higher moisture resistance.

Further, in the composition described in Patent Document 1, the urethane structure in urethane (meth) acrylate is hydrolyzed by moisture in the atmosphere, and the adhesive force is lowered and the airtightness is impaired, so that droplets are formed in the hollow portion. There was a problem that

Therefore, it is an object of the present invention to provide a sealing composition which can maintain a high adhesive force between adherends and has high moisture resistance even when used for sealing a hollow structure to be treated at a high temperature. To do.

〔式中、
Ａｒ^１は、以下から選択される２価の基であり、

Ｂ^１及びＢ^２は、独立に、置換されていてもよい炭素原子数１〜８のアルキレンであり、
Ｒ^１は、独立に、水素又はメチルであり、
Ｒ^２は、独立に、水素又はメチルであり、
ｍ１は、０〜３の整数であり、
ｍ２は、０〜３の整数である。〕
［３］（Ｂ）成分が、水素引き抜き型の光ラジカル重合開始剤である、［１］又は［２］の封止用組成物。
［４］更に、（Ｅ）：チキソ付与剤として、ヒュームドシリカを含む、［１］〜［３］のいずれかの封止用組成物。
［５］（Ａ）成分中の、（メタ）アクリルオリゴマーである（ａ−１）成分と、（メタ）アクリルモノマーである（ａ−２）成分との含有量の合計が７５〜１００質量％である、［１］〜［４］のいずれかの封止用組成物。
［６］（ａ−１）成分及び（ａ−２）成分の合計１００質量％に対して、（ａ−２）成分の含有量が２５〜３０質量％である、［１］〜［５］のいずれかに記載の封止用組成物。
［７］［１］〜［６］のいずれかに記載の封止用組成物のみからなる、光半導体及び光学的センサーからなる群より選択される、中空構造を有するパッケージ用の封止剤。 [1] (a-1): (meth) acrylic oligomer having a bisphenol skeleton, and (a-2): (meth) acrylic monomer having a hydroxyl group,
(A): At least one of the components (a-1) and (a-2) has an acryloyl group, (A): radical curable resin,
(B): Photoradical polymerization initiator, and (C): Filler (excluding fumed silica)
Containing composition for encapsulation.
[2] The sealing composition of [1], wherein the component (a-1) is represented by the following formula (1), and the component (a-2) is a hydroxyalkyl (meth) acrylate.

[In the formula,
Ar ¹ is a divalent group selected from the following,

B ¹ and B ² are independently optionally substituted alkylenes having 1 to 8 carbon atoms.
R ¹ is independently hydrogen or methyl and
R ² is independently hydrogen or methyl and
m1 is an integer from 0 to 3 and
m2 is an integer from 0 to 3. ]
[3] The sealing composition of [1] or [2], wherein the component (B) is a hydrogen abstraction type photoradical polymerization initiator.
[4] Further, (E): The sealing composition according to any one of [1] to [3], which contains fumed silica as a thixotropic agent.
[5] The total content of the component (a-1), which is a (meth) acrylic oligomer, and the component (a-2), which is a (meth) acrylic monomer, in the component (A) is 75 to 100% by mass. The sealing composition according to any one of [1] to [4].
[6] The content of the component (a-2) is 25 to 30% by mass with respect to the total of 100% by mass of the components (a-1) and (a-2) [1] to [5]. The sealing composition according to any one of.
[7] A sealing agent for a package having a hollow structure selected from the group consisting of an optical semiconductor and an optical sensor, which comprises only the sealing composition according to any one of [1] to [6].

According to the present invention, there is provided a sealing composition which can maintain a high adhesive force between adherends and has high moisture resistance even when used for sealing a hollow structure to be treated at a high temperature.

It is sectional drawing of the ceramic cavity type optical sensor. It is sectional drawing of the optical sensor of a chip size package type.

Hereinafter, preferred embodiments of the present invention will be described. As used herein, the term "(meth) acryloyl group" refers to an acryloyl group (CH ₂ = CH _2- C (= O)-) and a methacryloyl group (CH ₂ = CH (CH ₃ ) -C (= O)-). ) Includes at least one. "May be replaced" means "replacement or non-replacement".

The sealing composition of the present invention
(A-1): (meth) acrylic oligomer having a bisphenol skeleton, and (a-2): (meth) acrylic monomer having a hydroxyl group,
(A): At least one of the components (a-1) and (a-2) has an acryloyl group, (A): radical curable resin,
(B): Photoradical polymerization initiator, and (C): Filler (excluding fumed silica)
including.

[A: Radical curable resin]
The radical curable resin contains a (meth) acrylic oligomer having a (a-1) bisphenol skeleton and a (meth) acrylic monomer having a (a-2) hydroxyl group. At least one of the component (a-1) and the component (a-2) has an acryloyl group.

上記構造中、Ｒ^３及びＲ^４は、それぞれ独立に、水素、置換されていてもよい炭素数１〜２のアルキル基、又は置換されていてもよいフェニル基である。中でもＲ^３及びＲ^４がそれぞれ独立に、水素又はメチル基であることが好ましく、Ｒ^３及びＲ^４のいずれもがメチル基であることがより好ましい。 [(A-1) (meth) acrylic oligomer having a bisphenol skeleton]
The molecular weight of the (meth) acrylic oligomer is preferably 400 to 1100, more preferably 400 to 700.
Examples of the bisphenol skeleton of the (meth) acrylic oligomer include the following structures.

In the above structure, R ³ and R ⁴ are independently hydrogen, an alkyl group having 1 to 2 carbon atoms which may be substituted, or a phenyl group which may be substituted. Among these R ³ and R ⁴ are each independently, preferably a hydrogen or methyl group, and more preferably both of R ³ and R ⁴ are methyl groups.

The (meth) acrylic oligomer preferably has two (meth) acryloyl groups, that is, it preferably has (meth) acrylicloyl groups at both ends. When the number of (meth) acryloyl groups is 2, it is more excellent in heat resistance when exposed to a high temperature such as reflow. The (meth) acryloyl group is preferably formed by the reaction of epoxy and (meth) acrylic acid.

Examples of the structure other than both ends of the (meth) acrylic oligomer, that is, the main chain, are epoxy resin and polybutadiene from the viewpoint of adhesiveness, but epoxy resin is preferable. The main chain preferably has a hydroxyl group, and as the epoxy (meth) acrylate, an epoxy resin in which an epoxy reacts with (meth) acrylic acid to open a ring of an epoxy group and a hydroxyl group is formed is more preferable. The main chain may have an alkyloxy structure.

式中、Ａｒ^１は、以下から選択される２価の基である。

これらの中でも、接着力の観点から、Ａｒ^１は、ビスフェノールＡ、ビスフェノールＦがより好ましく、ビスフェノールＡがさらに好ましい。 As the (meth) acrylic oligomer having a bisphenol skeleton, a compound represented by the structural formula of the following formula (1) is preferable.

In the formula, Ar ¹ is a divalent group selected from the following.

Among these, from the viewpoint of adhesive strength, Ar ¹ is more preferably bisphenol A or bisphenol F, and even more preferably bisphenol A.

In the formula, B ¹ and B ² are alkylenes having 1 to 8 carbon atoms which may be substituted independently. The alkylene having 1 to 8 carbon atoms is linear or branched, and is methylene, ethylene, ethylidene (ethane-1,1-diyl), trimethylene, propylene (propane-1,2-diyl), propyridene (propyriden). Propane-1,1-diyl), isopropylidene (propane-2,2-diyl), tetramethylene, butylidene (butane-1,1-diyl), isobutylidene (2-methylpropane-1,1-diyl), penta Examples thereof include methylene, 2-methylpentane-1,5-diyl, hexamethylene, 2-ethylhexane-1,6-diyl, heptamethylene, octamethylene and the like. Among these, propylene and ethylene are preferable from the viewpoint of achieving both the flexibility of the cured product and the heat-resistant adhesiveness.

The alkylene having 1 to 8 carbon atoms may have a substituent such as halogen, alkyl, or alkoxy, but preferably does not have a substituent.

R ¹ is independently hydrogen or methyl. When the component (a-2) described later does not have an acryloyl group, it is hydrogen.
R ² is independently hydrogen or methyl.

m1 is an integer of 0 to 3, with an integer of 0 to 1 being more preferred.
m2 is an integer of 0 to 3, with an integer of 0 to 1 being more preferred.
When m1 and m2 are integers of 1 or more, the component (a-1) becomes flexible.
When m1 and m2 are integers of 0, the moisture resistance is excellent.
The (meth) acrylic oligomer having a bisphenol skeleton may be used alone or in combination of two or more.

Since the oligomer represented by the formula (1) has a hydroxyl group in the side chain, when polymerized with the component (a-2) having a hydroxyl group, the polymer has a large number of hydroxyl groups, and the adhesion between the adherends is increased. It is considered that it can be improved and the permeation of water can be suppressed. Therefore, the airtightness of the hollow structure is ensured.

[(A-2) (meth) acrylic monomer having a hydroxyl group]
The (meth) acrylic monomer having a hydroxyl group is preferably an aliphatic or hydroxyalkyl (meth) acrylate having an alkyl group having an alicyclic structure, and more preferably a hydroxyalkyl (meth) acrylate having an aliphatic alkyl group. Further, the (meth) acrylic monomer having a hydroxyl group does not contain a bisphenol skeleton.

Examples of the (meth) acrylic monomer having a hydroxyl group include hydroxyalkyls such as 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, and 4-hydroxybutyl (meth) acrylate. (Meta) acrylate; and 2- (meth) acryloyloxyethyl-2-hydroxypropylphthalate, 2-hydroxy-3- (meth) acryloyloxypropyl (meth) acrylate, caprolactone-modified 2-hydroxyethyl (meth) acrylate , Cyclohexanedimethanol Mono (meth) acrylate and other hydroxyl group-containing (meth) acrylates other than hydroxyalkyl (meth) acrylates. Among these, hydroxyalkyl (meth) acrylate is preferable, 2-hydroxybutyl (meth) acrylate and 4-hydroxybutyl (meth) acrylate are more preferable, and 4-hydroxybutyl (meth) acrylate is further preferable. The (meth) acrylic monomer having a hydroxyl group may be used alone or in combination of two or more.

When the component (a-1) does not contain an acryloyl group, the component (a-2) is an acrylic monomer having a hydroxyl group.
That is, at least one of the component (a-1) and the component (a-2) has an acryloyl group. Since one of them has an acryloyl group, it maintains sufficient adhesive strength even when exposed to high temperature conditions such as solder reflow, for example, 240 to 260 ° C., and does not cause floating or peeling. In particular, from the viewpoint of achieving both heat resistance and moisture resistance, it is preferable that the component (a-2) has an acryloyl group, and both the component (a-1) and the component (a-2) have an acryloyl group. preferable.

The ratio of the acrylic component in the curable resin (acrylate component / curable resin) is preferably 20 to 100% by mass, more preferably 75 to 100% by mass. The mass of the curable resin was the total mass of the component (a-1) and the component (a-2).

The total content of the component (a-1), which is a (meth) acrylic oligomer, and the component (a-2), which is a (meth) acrylic monomer, in the component (A) is the viewpoint of heat resistance and moisture resistance. Therefore, 75 to 100% by mass is preferable, and 100% by mass is more preferable.

From the viewpoint of heat resistance, the content of the component (a-2) is preferably 10 to 30% by mass with respect to the total of 100% by mass of the component (a-1) and the component (a-2), and is 20 to 30% by mass. % Is more preferable, and 25 to 30% by mass is further preferable.

From the viewpoint of adhesiveness, the component (A) is preferably 50 to 90% by mass, more preferably 60 to 90% by mass, and even more preferably 70 to 80% by mass with respect to 100% by mass of the sealing composition.

[(B) Photoradical polymerization initiator]
The photoradical polymerization initiator is not particularly limited as long as it is a compound that generates radicals by irradiation with light. Examples of the photoradical polymerization initiator include benzoins, acetophenones, benzophenones, benzosverones, xanthones, thioxanthones, α-acyloxime esters, phenylglycilates, benzyls, azo compounds, and diphenyl sulfide compounds. , Acylphosphine oxide compounds, benzoin ethers, anthraquinones and the like. Specifically, the photoradical polymerization initiator is 1- [4- (2-hydroxyethoxy) phenyl] -2-hydroxy-2-methyl-1-propane-1-one, 1-hydroxy-cyclohexyl-phenyl-. Ketone, benzophenone, 2,2-dimethoxy-1,2-diphenylethane-1-one, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, 2,4,6-trimethylbenzoylphenylethoxyphosphine oxide, 2-benzyl- 2-Dimethylamino-1- (4-morpholinophenyl) butanone-1,2-hydroxy-2-methyl-1-phenyl-propane-1-one, 2-methyl-1- [4-methylthio] phenyl] -2 -Morholinopropan-1-one, oligo [2-hydroxy-2-methyl-1- [4- (1-methylvinyl) phenyl] propanone], oligo [2-hydroxy-2-methyl-1- [4- ( 1-Methylvinyl) phenyl] propanone], benzoin methyl ether, benzoin ethyl ether, benzoin isobutyl ether, benzoin isopropyl ether, bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide, oligo 2-hydroxy-2-methyl -1- [4- (1-methylvinyl) phenyl] propanol, oligo 2-hydroxy-2-methyl-1- [4- (1-methylvinyl) phenyl] propanol, 2-hydroxy-2-methyl-1- Phenyl-1-propanone, isopropylthioxanthone, methyl o-benzoylbenzoate, [4- (methylphenylthio) phenyl] phenylmethane, 2,4-diethylthioxanthone, 2-chlorothioxanthone, benzophenone, ethylanthraquinone, benzophenone ammonium salt, Thioxanthone ammonium salt, bis (2,6-dimethoxybenzoyl) -2,4,4-trimethyl-pentylphosphine oxide, bis (2,6-dimethoxybenzoyl) -2,4,4-trimethyl-pentylphosphine oxide, 2, 4,6-trimethylbenzophenone, 4,4'-bis (diethylamino) benzophenone, 4-methylbenzophenone, 1,4-dibenzoylbenzene, 10-butyl-2-chloroacrydone, 2,2'bis (o-chlorophenyl) ) 4,5,4', 5'-tetrakis (3,4,5-trimethoxyphenyl) 1,2'-biimidazole, 2,2'bis (o-chlorophenyl) ) 4,5,4', 5'-Tetraphenyl-1,2'-biimidazole, 4-benzoyldiphenyl ether, acrylicized benzophenone, bis (η5-2,4-cyclopentadiene-1-yl) -bis (2) , 6-Difluoro-3- (1H-pyrrole-1-yl) -phenyl) titanium, o-methylbenzoylbenzoate, p-dimethylaminobenzoic acid ethyl ester, p-dimethylaminobenzoic acid isoamylethyl ester, active tertiary amine , Carbazole / phenyl group photopolymerization initiator, aclysin type photopolymerization initiator, triazine type photopolymerization initiator, benzoyl type photopolymerization initiator and the like. Among these, hydrogen abstraction type photoradical polymerization initiators are preferable from the viewpoint of outgas, and examples of hydrogen abstraction type photoradical polymerization initiators include benzophenones, dibenzosverones, anthraquinones, xanthones, and thioxanthones. Specific examples thereof include 2,4-diethylthioxanthone, 4,4'-bis (diethylamino) benzophenone, and 4-methylbenzophenone. The photoradical polymerization initiator may be used alone or in combination of two or more.

From the viewpoint of curability, the component (B) is preferably 0.1 to 2 parts by mass, more preferably 0.5 to 2 parts by mass, and 0.7 to 2 parts by mass with respect to 100 parts by mass of the component (A). Is even more preferable.

[(C) Filler]
The filler is not particularly limited, and examples thereof include known inorganic fillers and organic fillers. As inorganic fillers, calcium carbonate, magnesium carbonate, barium sulfate, magnesium sulfate, aluminum silicate, titanium oxide, alumina, zinc oxide, silicon dioxide, kaolin, talc, glass beads, sericite jar, bentonite, aluminum nitride, and nitrided Silicon is mentioned. Examples of the organic filler include polymethyl methacrylate, polystyrene, copolymers obtained by copolymerizing the monomers constituting these with other monomers, polyester fine particles, polyurethane fine particles, and rubber fine particles, and among these, adhesion From the viewpoint of properties, an inorganic filler is preferable, silicon dioxide, glass beads and talc are more preferable, and talc is further preferable. The filler may be used alone or in combination of two or more.
The filler does not contain fumed silica. This is because it is used as a thixotropic agent.

From the viewpoint of adhesiveness with respect to 100 parts by mass of the component (A), the component (C) is preferably 10 to 50 parts by mass, more preferably 20 to 40 parts by mass, and even more preferably 25 to 35 parts by mass.

[Other ingredients]
((D) Coupling agent)
A coupling agent can be added to the sealing composition of the present invention for the purpose of further improving the adhesiveness. Coupling agents include silane coupling agents such as vinyltrimethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyl. Diethoxysilane, 3-glycidoxypropyltriethoxysilane, p-styryltrimethoxysilane, 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropylmethyldiethoxysilane, 3 − Methacryloxypropyltriethoxysilane, 3-acryloxypropyltrimethoxysilane, N-2- (aminoethyl) -3-aminopropylmethyldimethoxysilane, N-2- (aminoethyl) -3-aminopropyltrimethoxysilane , N-2- (aminoethyl) -3-aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-triethoxysilyl-N- (1,3-dimethyl-butylidene) ) Ppropylamine, N-phenyl-3-aminopropyltrimethoxysilane, 3-ureidopropyltriethoxysilane, 3-chloropropyltrimethoxysilane, 3-mercaptopropyl, methyldimethoxysilane, 3-mercaptopropyltrimethoxysilane, bis Examples thereof include (triethoxysilylpropyl) tetrasulfide and 3-isocyanuspropyltriethoxysilane. The coupling agent may be used alone or in combination of two or more.
From the viewpoint of adhesiveness, the component (D) is preferably 0.5 to 3 parts by mass, more preferably 1 to 2 parts by mass with respect to 100 parts by mass of the component (A).

((E) Thixotropy)
The sealing composition of the present invention may contain a thixotropy-imparting agent for the purpose of improving coatability and the like. The thixo-imparting agent is not particularly limited, and examples thereof include fine particle silica such as fumed silica, fine particle alumina, and aliphatic amide, and fumed silica is preferable from the viewpoint of coatability. The thixotropy may be used alone or in combination of two or more.
From the viewpoint of coatability, the component (E) is preferably 3 to 20 parts by mass, more preferably 5 to 15 parts by mass with respect to 100 parts by mass of the component (A).

(Thermal radical polymerization initiator)
The sealing composition of the present invention may contain a thermal radical polymerization initiator. The thermal radical polymerization initiator is not particularly limited as long as it is a compound that generates radicals by heating, and examples thereof include organic peroxides.

The organic peroxide may be any organic compound containing a peroxy group (-O-O-), for example, diacyl peroxides, hydroperoxides, dialkyl peroxides, peroxyketals, peroxyesters, peroxycarbonates. And so on.

Specific examples of organic peroxides include diacyl peroxides such as dilauroyl peroxide, dibenzoyl peroxide, bis-3,5,5-trimethylhexanoyl peroxide; 1,1,3,3-tetramethylbutylhydro. Hydroperoxides such as peroxides, cumene hydroperoxides (eg, Kayakumen H manufactured by Chemicals Aguzo), t-butyl hydroperoxides; t-hexylperoxy2-ethylhexanoate, dicumylperoxides, 2,5-dimethyl. -2,5-di (t-butylperoxy) hexane, 1,3-bis (t-butylperoxyisopropyl) benzene, t-butylcumyl peroxide, di-t-butyl peroxide, 2,5-dimethyl-2, Dialkyl peroxides such as 5-di (t-butylperoxy) hexin-3; 2,2-bis (4,5-di-t-butylperoxycyclohexyl) propane, 1,1-di-t-butylperoxycyclohexane Peroxyketals such as 2,2-di-t-butylperoxybutane; 1,1,3,3-tetramethylbutylperoxyneodecanoate, α-cumylperoxyneodecanoate, t-butyl Peroxyneodecanoate, t-butylperoxyneoheptanoate, t-butylperoxypivalate, 1,1,3,3-tetramethylbutylperoxy2-ethylhexanoate, t-amylperoxy2-ethylhexanoate Ate, t-butylperoxy2-ethylhexanoate, di-t-butylperoxyhexahydroterephthalate, t-amylperoxy3,5,5-trimethylhexanoate, t-butylperoxyacetate, t-butylperoxybenzoate, Peroxyesters such as t-hexylperoxybenzoate, t-amylperoxybenzoate; di-2-ethylhexylperoxydicarbonate, diisopropylperoxydicarbonate, t-butylperoxyisopropylcarbonate, t-butylperoxy2-ethylhexyl carbonate, 1, Examples thereof include peroxy carbonates such as 6-bis (t-butylperoxycarbonyloxy) hexane. The thermal radical polymerization initiator may be used alone or in combination of two or more.

(Photosensitizer)
The sealing composition of the present invention may further contain a photosensitizer in order to increase the sensitivity to light during photocuring.

(Other resins)
The sealing composition may contain other resins. Examples of other resins include conventional resins having unsaturated groups and / or epoxy groups used as the main agent of conventional sealing compositions, and resins having neither unsaturated groups nor epoxy groups. .. Here, the "unsaturated group" means an ethylenically unsaturated group and / or an acetylene unsaturated group. Other resins preferably have a hydroxyl group. Other resins may be used alone or in combination of two or more.
The other resin is preferably 0 to 50% by mass, more preferably 0% by mass, based on 100% by mass of the sealing composition.

(Other monomers)
The sealing composition may contain other monomers. Examples of other monomers include monomers having an unsaturated group. Other monomers preferably have a hydroxyl group. Other monomers may be used alone or in combination of two or more.
When the other monomer is contained, it is preferably 0 to 30% by mass, more preferably 0% by mass, based on 100% by mass of the sealing composition.

[Composition]
The sealing composition is obtained by mixing each component at room temperature using an apparatus such as a planetary mixer.

The sealing composition is used after being cured by irradiation with energy rays such as ultraviolet rays. It is used by applying heat as needed.

[Use]
The sealing composition of the present invention is suitably used for sealing semiconductor packages such as optical sensors and optical semiconductors.
As the types of semiconductor packages, FIG. 1 shows a ceramic cavity type, and FIG. 2 shows a chip size package type.
As shown in FIG. 1, in the ceramic cavity type, the sealing composition is used to bond the cavity 4 to the glass plate or plastic plate 1. The thickness of the cured product 2 of the sealing composition in this type is usually about 5 to 30 μm. As shown in FIG. 2, in the chip size package type, the sealing composition is used to bond the semiconductor 3 to the glass plate or the plastic plate 1. The thickness of the cured product 2 of the sealing composition in this type is usually about 100 to 200 μm.
Since the sealing composition has excellent moisture resistance, it is difficult for moisture to permeate even if the cured product is thick, so that it is suitably used for a chip size package type.
In addition to the above applications, the sealing composition is also used as a sealing material for display elements, light amount adjusting elements, focus variable elements, light modulation elements, and the like.

Next, specific embodiments of the present invention will be described in more detail with reference to Examples, but the present invention is not limited to these examples.

エポキシエステル３０００ＭＫ：下記構造の化合物（共栄社化学株式会社製）

エポキシエステル３００２Ａ（Ｎ）：下記構造の化合物（共栄社化学株式会社製）

エポキシエステル３００２Ｍ（Ｎ）：下記構造の化合物（共栄社化学株式会社製）

ＥＸＡ８０６７ハーフエステル：下記構造の化合物（ｎ＝１〜３）

２−ヒドロキシブチルメタクリレート：ライトエステルＨＯＢ（Ｎ）（共栄社化学株式会社製）
４−ヒドロキシブチルアクリレート：４−ＨＢＡ（大阪有機化学工業株式会社製）
３−メタクリロキシプロピルトリメトキシシラン：ＫＢＭ−５０３（信越化学株式会社製）
１−ヒドロキシシクロヘキシルフェニルケトン：Ｏｍｎｉｒａｄ１８４（ＩＧＭ Ｒｅｓｉｎｓ Ｂ．Ｖ．製）
ビス（２，４，６−トリメチルベンゾイル）フェニルホスフィンオキサイド：Ｏｍｎｉｒａｄ８１９（ＩＧＭ Ｒｅｓｉｎｓ Ｂ．Ｖ．製）
２，４−ジエチルチオキサントン：ＤＥＴＸ−Ｓ（日本化薬株式会社製）
タルク：ＳＧ−９５ＳＫ（日本タルク株式会社製）
ヒュームドシリカ：ＴＧ−３０８Ｆ（ＣＡＢＯＴ株式会社製） Epoxy ester 3000A: Compound with the following structure (manufactured by Kyoeisha Chemical Co., Ltd.)

Epoxy ester 3000MK: Compound with the following structure (manufactured by Kyoeisha Chemical Co., Ltd.)

Epoxy ester 3002A (N): Compound with the following structure (manufactured by Kyoeisha Chemical Co., Ltd.)

Epoxy ester 3002M (N): Compound with the following structure (manufactured by Kyoeisha Chemical Co., Ltd.)

EXA8067 Half Ester: Compound with the following structure (n = 1-3)

2-Hydroxybutyl methacrylate: Light ester HOB (N) (manufactured by Kyoeisha Chemical Co., Ltd.)
4-Hydroxybutyl acrylate: 4-HBA (manufactured by Osaka Organic Chemical Industry Co., Ltd.)
3-methacryloxypropyltrimethoxysilane: KBM-503 (manufactured by Shin-Etsu Chemical Co., Ltd.)
1-Hydroxycyclohexylphenyl ketone: Omnirad184 (manufactured by IGM Resins VV)
Bis (2,4,6-trimethylbenzoyl) phenylphosphine oxide: Omnirad 819 (manufactured by IGM Resins BV)
2,4-Diethylthioxanthone: DETX-S (manufactured by Nippon Kayaku Co., Ltd.)
Talc: SG-95SK (manufactured by Japan Talc Co., Ltd.)
Fumed silica: TG-308F (manufactured by CABOT Corporation)

[Synthesis Example 1] EXA8067 Half Ester Bisphenol A Type Epoxy Resin (EXA-8067, manufactured by DIC Corporation) 480.0 g, Methacrylic Acid (manufactured by Tokyo Chemical Industry Co., Ltd.) 86.1 g, and Triphenylphosphine (Tokyo Chemical Industry Co., Ltd.) (Manufactured by the company) 500 mg was mixed and stirred at 100 ° C. for 6 hours. 554.8 g of EXA8067 half ester of a pale yellow transparent viscous substance was obtained.

[Examples 1 to 8 and Comparative Examples 1 to 3]
A sealing composition was produced by blending the components shown in Table 1 at the blending ratio shown in Table 1, and the test pieces obtained using each of the produced compositions were evaluated based on the following evaluation test methods. The results are shown in Table 1. The unit of the blending amount of each component in Table 1 is a mass part.

[Creation of test piece]
Using borosilicate glass (“D263Teco” manufactured by Matsunami Glass Industry Co., Ltd.), glass plates A: 10.0 mm × 10.0 mm × 0.5 mm and glass plates B: 13.6 mm × 13 which are two sizes of glass plates. .6 mm × 0.5 mm was prepared. On the glass plate B, 2 mg each of the sealing compositions obtained in Examples 1 to 8 and Comparative Examples 1 to 3 was used with a needle made of a precision nozzle having an inner diameter of 200 μm, and the size of the center was 9 mm square and the line width was 250 to 250. It was applied at 300 μm. Glass A was attached to the center of glass B using a jig. The bonded glass was irradiated with ultraviolet rays of 200 mW / cm ² for 30 seconds, the sealing composition was photocured, and then heat-cured at 120 ° C. for 30 minutes to prepare a test piece. The actual thickness of the cured product was 150 to 160 μm.

[Heat resistance test (1)]
On a hot plate set at 180 ° C., the test piece was heat-pressed for 5 minutes while being pressurized with a weight of 550 g. After hot pressing, the test pieces were stored at room temperature, and the next day, the states of the glass plates A and B were judged according to the following criteria.
〇: There is no floating or peeling between the glass plate A and the glass plate B.
Δ: There is a float between the glass plate A and the glass plate B, but there is no peeling.
X: There is peeling between the glass plate A and the glass plate B.
Note that "floating" means a state in which the glass plate A and the glass plate B are not completely in close contact with each other, but the inside and the outside of the adhesive are blocked from each other, and "peeling" means the glass plate A. And the glass plate B are peeled off, and the insulation between the inside and the outside of the adhesive is not maintained.

[Heat resistance test (2)]
The test piece was placed in a reflow oven, heated, heated at 180 ° C. for 150 seconds, further heated at 250 to 260 ° C. for 25 seconds, and then lowered. After reflow, the test pieces were stored at room temperature, and the next day, the states of the glass plates A and B were judged according to the following criteria.
〇: There is no floating or peeling between the glass plate A and the glass plate B.
Δ: There is a float between the glass plate A and the glass plate B, but there is no peeling.
X: There is peeling between the glass plate A and the glass plate B.

[Moisture resistance test]
The state of the glass plates A and B after the test piece was placed at 85 ° C. and 85% RH for 100 hours was judged according to the following criteria.
〇: There is no floating or peeling between the glass plate A and the glass plate B.
Δ: There is a float between the glass plate A and the glass plate B, but there is no peeling.
X: There is peeling between the glass plate A and the glass plate B.
[Maximum droplet size]
After each of the heat resistance test (1), heat resistance test (2), and moisture resistance test, the size of the droplets existing between the glass plate A and the glass plate B is determined by measuring the size of the droplets existing between the glass plate A and the glass plate B. ) Was measured, and the maximum size of the droplet was judged according to the following criteria.
⊚: The maximum size of the droplet existing between the glass plate A and the glass plate B is 2 μm or less.
◯: The maximum size of the droplet existing between the glass plate A and the glass plate B is more than 2 μm and less than 5 μm.
Δ: The maximum size of the droplet existing between the glass plate A and the glass plate B is more than 5 μm and 10 μm or less.
X: The maximum size of the droplet existing between the glass plate A and the glass plate B exceeds 10 μm.
Table 1 also shows the maximum size (maximum size) of the droplet.

<Measurement of composition characteristics (storage elastic modulus and Tg)>
A 0.5 × 5 × 50 mm plate-shaped cured product was prepared by irradiating the sealing composition with ultraviolet rays of ^{6000 mJ / cm 2 using} a metal halide lamp (manufactured by Eye Graphics, GCS-401GX). The dynamic viscoelasticity of this plate-shaped cured product was measured using a measuring device "DMS-6100" (manufactured by SII), and E'(storage elastic modulus) and E'(loss elastic modulus) were determined. From tan δ = E'' / E', the peak top temperature of tan δ was defined as Tg.

The results are shown in Table 1.

The sealant of the example was excellent in heat resistance and moisture resistance.
Comparing Example 3 and Example 4, when the component (a-2) was an acrylate monomer, the moisture resistance was more excellent.
Comparing Example 4 and Example 5, when the component (a-1) was an acrylate oligomer, it was superior in moisture resistance.
Comparing Examples 3 and 6 and Examples 4 and 7, when the component (B) was a hydrogen abstraction type photopolymerization initiator, it was superior in moisture resistance.
Comparing Example 1 and Example 8, when the amount of the hydroxyl group of the component (a-1) was large, the heat resistance was superior.
By comparing Examples 1 and 2 with Example 3, the content of the component (a-2) was 25% by weight with respect to the total of 100% by weight of the components (a-1) and (a-2). In the above cases, the heat resistance was superior.

On the other hand, the encapsulant of Comparative Example 1 was inferior in moisture resistance because it did not contain a filler.
The encapsulant of Comparative Example 2 was inferior in heat resistance because neither the oligomer nor the monomer had an acryloyl group.
The encapsulant of Comparative Example 3 was inferior in heat resistance because neither the oligomer nor the monomer had an acryloyl group and the oligomer was monofunctional.

1: Glass plate or plastic plate 2: Cured product of sealing composition 3: Semiconductor 4: Cavity

Claims (7)

(A-1): (meth) acrylic oligomer having a bisphenol skeleton, and (a-2): (meth) acrylic monomer having a hydroxyl group,
(A): At least one of the components (a-1) and (a-2) has an acryloyl group, (A): radical curable resin,
(B): Photoradical polymerization initiator, and (C): Filler (excluding fumed silica)
Containing composition for encapsulation. The sealing composition according to claim 1, wherein the component (a-1) is represented by the following formula (1), and the component (a-2) is a hydroxyalkyl (meth) acrylate.

[In the formula,
Ar ¹ is a divalent group selected from the following,

B ¹ and B ² are independently optionally substituted alkylenes having 1 to 8 carbon atoms.
R ¹ is independently hydrogen or methyl and
R ² is independently hydrogen or methyl and
m1 is an integer from 0 to 3 and
m2 is an integer from 0 to 3. ] The sealing composition according to claim 1 or 2, wherein the component (B) is a hydrogen abstraction type photoradical polymerization initiator. (E): The sealing composition according to any one of claims 1 to 3, which contains fumed silica as a thixotropic agent. The total content of the component (a-1), which is a (meth) acrylic oligomer, and the component (a-2), which is a (meth) acrylic monomer, in the component (A) is 75 to 100% by mass. The sealing composition according to any one of claims 1 to 4. Any one of claims 1 to 5, wherein the content of the component (a-2) is 25 to 30% by mass with respect to the total of 100% by mass of the component (a-1) and the component (a-2). The sealing composition according to. A sealing agent for a package having a hollow structure selected from the group consisting of an optical semiconductor and an optical sensor, which comprises only the sealing composition according to any one of claims 1 to 6.

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