JP4134605B2 - Active energy ray-curable adhesive composition - Google Patents

Description

【００１０】
（但し、式（１）において、Ｒ₁は水素原子またはメチル基、Ｒ₂はアルキレン基、ａおよびｂはそれぞれ独立に０〜５の整数である。）
本発明で使用する(Ａ)成分は、上記式（１）の通りトランス体である必要がある。同じ構造のジ（メタ）アクリレートであっても、シス体の場合は、得られる硬化物の硬度及び耐久性が不充分となってしまう。
Ｒ₂としてはメチレン基、エチレン基およびプロピレン基等の炭素数１〜４のアルキレン基が好ましい。ａ及びｂとしては、特にａ及びｂいずれも０であることが好ましい。
【００１１】
(Ａ)成分の具体例としては、式（１）において、Ｒ₁が水素原子、ａ及びｂがそれぞれ０であるトランス−ノルボルナンジメチロールジアクリレート、Ｒ₁がメチル基、Ｒ₂がエチレン基で、並びにａ及びｂがそれぞれ１である、トランス−ノルボルナンジメチロールエチレンオキサイド２モル変性物のジアクリレート等を挙げることができる。
【００１２】
本発明の接着剤組成物には、組成物の可撓性を上げるために、骨格が(Ａ)成分と類似し、相溶性に優れる下記一般式（２）、一般式（３）、または一般式（４）で示される分子中に１個のアクリロイル基を有する（メタ）アクリレート（Ｂ成分）を併用することが好ましい。
【００１３】
【化６】

【００１４】
（但し、式（２）で表されるジシクロペンタジエン骨格を有する（メタ）アクリレートにおいて、Ｒ₃は水素原子またはメチル基、Ｒ₄はメチレン基または基−ＣＨ₂ＣＨ₂Ｏ−あるいは−ＣＨ₂ＣＨ（ＣＨ₃）Ｏ−、ｃは０〜４の整数である。）
【００１５】
【化７】

【００１６】
（但し、式（３）で表されるトリシクロデカン骨格を有する（メタ）アクリレートにおいて、Ｒ₅は水素原子またはメチル基、Ｒ₆はメチレン基または基−ＣＨ₂ＣＨ₂Ｏ−あるいは−ＣＨ₂ＣＨ（ＣＨ₃）Ｏ−、ｄは０〜４の整数である。）
【００１７】
【化８】

【００１８】
（但し、式（４）で表されるノルボルナン骨格を有する（メタ）アクリレートにおいて、Ｒ₇は水素原子またはメチル基である。）
【００１９】
本発明において、式（２）〜式（４）で示される（メタ）アクリレートのうち少なくとも１種からなる(Ｂ)成分が、(Ａ)、(Ｂ)および後記(Ｃ)成分の合計量１００質量部に対して、５〜３０質量部含まれていることが好ましい。この(Ｂ)成分は５質量部を下回ると十分な可撓性が得られず、３０質量部を超えると、接着力が不足してしまうため好ましくない。(Ｂ)成分の代わりに、たとえばメチル（メタ）アクリレート、エチル（メタ）アクリレート、ブチル（メタ）アクリレート等、他の分子中に１個の(メタ)アクリロイル基を有する（メタ）アクリレートを使用することもできるが、接着剤の凝集力が低下してしまうために、結果として耐久性のない接着剤となってしまうおそれがある。
【００２０】
本発明の接着剤組成物は、(Ａ)成分および(Ｂ)成分の他に、接着剤のベース樹脂としての物性を付与する目的で、分子の両末端に(メタ)アクリロイル基を有するウレタン（メタ）アクリレートおよび／またはエポキシ（メタ）アクリレート（Ｃ成分）を併用することが好ましい。
【００２１】
ウレタン（メタ）アクリレートの具体例としては、イソシアネート（例えば、トリレンジイソシアネート、ジフェニルメタンジイソシアネート、ヘキサメチレンジイソシアネート、キシリレンジイソシアネート、イソホロンジイソシアネートなど）と、ジオール（例えばエチレングリコール、プロピレングリコール、ヘキサメチレングリコール、ポリエチレングリコールなど）との付加反応生成物であるポリウレタンを骨格とし、分子末端に（メタ）アクリレートを付加させた、分子中に２個の（メタ）アクリロイル基を有するウレタン（メタ）アクリレートである。ウレタン（メタ）アクリレートの好ましい分子量は５００〜４０００である。その分子量が５００を下回ると接着力が不足し、逆に４０００を超えると接着剤の粘度を低下させるために希釈モノマーが必要となり、これらの添加が接着剤の物性を低下させてしまうおそれがある。
【００２２】
エポキシ（メタ）アクリレートは、公知のものが使用できる。これらは例えば、グリシジル基含有化合物と（メタ）アクリル酸との反応により合成される。グリシジル基含有化合物としては例えばビスフェノールＡ型樹脂、ビスフェノールＦ型樹脂、ビスフェノールＺ型樹脂、フェノールノボラック型エポキシ樹脂、クレゾールノボラック型エポキシ樹脂等が挙げられる。
(Ｃ)成分を配合する割合は、(Ａ)、(Ｂ)および(Ｃ)成分の合計量１００質量部に対して、５〜８５質量部の割合で使用されることが好ましい。含有量が５質量部を下回ると、接着剤としての凝集力と可撓性のバランスがとれなくなり、基材フィルムに対する接着剤も不足する。逆に８５質量部を超えると、接着剤としての強度が不足する場合がある。
【００２３】
本発明の接着剤組成物は、電子線、可視光線及び紫外線等の活性エネルギー線の照射により硬化するものであるが、膜厚の大きい樹脂シートを得るためには、可視光線又は紫外線硬化型とすることが好ましい。
可視光線又は紫外線硬化型組成物とする場合、組成物に光重合開始剤(Ｄ成分)を配合する。(Ｄ)成分を配合する場合の割合としては、(Ａ)、(Ｂ)および(Ｃ)成分の合計量１００質量部に対して０．０５〜１２質量部が好ましく、より好ましくは０．１〜２質量部である。
なお、電子線硬化型とする場合は、(Ｄ)成分を配合する必要は必ずしもない。 (Ｄ)成分の具体例としては、ベンゾイン、ベンゾインメチルエーテル及びベンゾインプロピルエーテル等のベンゾイン類；アセトフェノン、２，２−ジメトキシ−２−フェニルアセトフェノン、２，２−ジエトキシ−２−フェニルアセトフェノン、１，１−ジクロロアセトフェノン、１−ヒドロキシシクロヘキシルフェニルケトン、２−メチル−１−［４−（メチルチオ）フェニル］−２−モルフォリノ−プロパン−１−オン及びＮ，Ｎ−ジメチルアミノアセトフェノン等のアセトフェノン類；２−メチルアントラキノン、１−クロロアントラキノン及び２−アミルアントラキノン等のアントラキノン類；２，４−ジメチルチオキサントン、２，４−ジエチルチオキサントン、２−クロロチオキサントン及び２，４−ジイソプロピルチオキサントン等のチオキサントン類；アセトフェノンジメチルケタール及びベンジルジメチルケタール等のケタール類；ベンゾフェノン、メチルベンゾフェノン、４，４‘−ジクロロベンゾフェノン、４，４’−ビスジエチルアミノベンゾフェノン、ミヒラーズケトン及び４−ベンゾイル−４‘−メチルジフェニルサルファイド等のベンゾフェノン類；並びに２，４，６−トリメチルベンゾイルジフェニルホスフィンオキサイド等が挙げられる。
(Ｄ)成分は単独で使用しても、２種以上を併用しても良い。
(Ｄ)成分には、必要に応じて光増感剤を併用することができる。光増感剤としては、Ｎ，Ｎ−ジメチルアミノ安息香酸エチルエステル、Ｎ，Ｎ−ジメチルアミノ安息香酸イソアミルエステル、トリエチルアミン及びトリエタノールアミン等が挙げられる。
【００２４】
本発明の接着剤組成物には、その他の成分として、金属材料等への接着力を高める目的で、例えば（メタ）アクリロイルオキシエチルホスフェート、ビス（メタ）アクリロイルオキシエチルホスフェート等のリン酸基を含有する化合物を添加することも可能である。ただし、これらは接着剤組成物との相溶性があまり良好ではないため、(Ａ)、(Ｂ)および(Ｃ)成分の合計量１００質量部に対して、１０質量部を超えないことが好ましい。また、必要に応じて、シランカップリング剤、重合禁止剤等を添加することもできる。
【００２５】
シランカップリング剤としては、例えば、γ−（２−アミノエチル）アミノプロピルトリメトキシシラン、γ−メタクリロキシプロピルトリメトキシシラン、γ−メルカプトプロピルトリメトキシシラン等が挙げられる。
【００２６】
重合禁止剤としては、例えば、ハイドロキノン、ハイドロキノンモノメチルエーテル、ｔ−ブチルカテコール、ｐ−ベンゾキノン等が挙げられる。
【００２７】
シランカップリング剤、重合禁止剤等の使用量は、(Ａ)、(Ｂ)および(Ｃ)成分の合計量１００質量部に対して、１０質量部までの範囲で使用することが好ましい。
【００２８】
本発明の接着剤組成物において、電子線で硬化させる場合には、(Ｄ)成分を用いる必要はなく、その他の活性エネルギー線を使用する場合には、常法に従い、各成分(Ａ)〜(Ｄ)を混合することにより得ることができる。
【００２９】
本発明の接着剤組成物の使用方法としては、金属薄膜層などが施されたポリカーボネート等の基材に本組成物を塗布した後、貼合わせ用基材のポリカーボネートなどを被せ、活性エネルギー線を照射する。
基材としては、ポリカーボネート、ポリメチルメタクリレート等の成形樹脂加工品、金属薄膜が施されたポリカーボネート、フィルム等が挙げられる。
【００３０】
【実施例】
以下に本発明を実施例および比較例を挙げ説明するが、本発明は以下の実施例によって制限されるものではない。なお、以下において、部はすべて質量部を示す。
【００３１】
○実施例１〜同４、比較例１及び２
表１に示す組成で、式（１）で表されるジ（メタ）アクリレート（Ａ成分）、分子中に１個の(メタ)アクリロイル基を有する（メタ）アクリレート（Ｂ成分）、ウレタン（メタ）アクリレートおよび／またはエポキシ(メタ)アクリレート（Ｃ成分）、および光重合開始剤（Ｄ成分）を混合し、活性エネルギー線硬化型接着剤組成物を調製した。この接着剤組成物を、スピンコーターを用いて、ＰＣ基板、アルミニウムを蒸着したＰＣ基板に厚さ５μｍで塗布した。さらにその上から、ポリカーボネートを被せた。次に、コンベアスピード５ｍ／分、出力１６０Ｗ／ｃｍの高圧水銀ランプで０．８Ｊ／ｃｍ²の条件で紫外線照射を１０回行った。
【００３２】
このようにして得られた硬化塗膜を施した試験材料を用いて、以下の項目について評価した。その結果を表１に示す。実施例２〜４、および比較例１〜２の結果もあわせて表１に示す。
【００３３】
○評価
（１）接着性試験
基板上に組成物を塗布したさらにその上から、ポリカーボネートのテストピース（日本テストパネル工業株式会社製：3.0mm×25mm×100mm）をかぶせて活性エネルギー線照射を行い、引っ張りせん断接着強度を測定した。
（２）耐久性試験
アルミニウムを蒸着したPC基板上に得られた硬化物を、８０℃温水中で２４時間静置した後に、アルミニウム基板の外観に異常がないかを観察し、異常のないものを○、外観が変化したものを×とした。
【００３４】
【表１】

【００３５】
なお、表１における略号は以下の意味を示す。
ｔ−ＮＤＭＤＡ：trans-ノルボルナンジメチロールジアクリレート
ＦＡ−５１３Ａ：日立化成工業(株)製 トリシクロデカニルアクリレート
ＴＣＤＭＡ：トリシクロデカンメチロールアクリレート
ＦＡ−５１１Ａ：日立化成工業(株)製 ジシクロペンテニルアクリレート
ＮＭＡ：ノルボルナンメチロールアクリレート
Ｍ−１３１０：東亞合成(株)製 ウレタンアクリレート
Ｍ−１６００：東亞合成(株)製 ウレタンアクリレート
エポキシエステル３００２Ａ：共栄社化学(株)製 ビスフェノールＡのプロピレンオキサイド2mol付加物ジグリシジルエーテルのアクリル酸付加物
ＨＣＰＫ：１−ヒドロキシシクロヘキシルフェニルケトン
ＢＤＭＫ：ベンジルジメチルケタール
Ｍ−２４０：東亞合成(株)製 ポリエチレングリコールジアクリレート
Ｍ−４０８：東亞合成(株)製 ジトリメチロールプロパンテトラアクリレート
【００３６】
実施例からも明らかなように、本発明の活性エネルギー線硬化型接着剤組成物は接着性が良好であり、さらに高温・高湿下における硬化膜の耐久性ならびに基材の保護効果に優れるものであった。一方、比較例２の接着性試験ではテストピースが全く接着せず、引張りせん断強度は計測不能もあった。このように比較例に示したものでは、十分な接着力ならびに耐久性を得ることができない。
【００３７】
【発明の効果】
本発明の接着剤組成物は、紫外線、可視光線、電子線などの活性エネルギー線で硬化させることにより、ポリカーボネートのようなプラスチック、およびアルミニウム等に対して優れた接着性を示す。また、高温・高湿下でも安定した接着力および基板の保護に優れた効果を示すものである。本発明により得られる活性エネルギー線硬化型接着剤組成物は、特にプラスチック、金属への接着性や基板の保護効果を要求されるような、例えば光ディスク用接着剤、特にDVD等の張り合わせ用の接着剤として有用なものである。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an active energy ray-curable adhesive composition, and the adhesive composition obtained by the present invention has an adhesive force, workability, paintability, and high temperature and high humidity as compared with conventional techniques. It is an adhesive composition having excellent durability.
[0002]
[Prior art]
A thermosetting adhesive containing an organic solvent such as toluene, xylene, ethyl acetate, butyl acetate or the like is usually used for laminating films such as production of film laminates and vinyl chloride resin metal laminates. However, in recent years, the working environment is contaminated by organic solvents, and when a thin film is used due to the heat-curing type, the base film is thermally deformed, resulting in a “rippling” appearance on the surface. For this reason, the problem that the laminate of a smooth finish cannot be obtained has arisen.
[0003]
As a method for solving the problems of the adhesive, an active energy ray-curable adhesive that does not require heating without a solvent has been proposed. For example, Japanese Patent Publication No. 2-7346 discloses an adhesive composition comprising a urethane polyacrylate having a molecular weight of 500 to 8000, a polyester diacrylate, a monofunctional polymer, and a phosphorus-containing monomer. Further, JP-A-2-132172 discloses an adhesive in which a vinyl chloride resin and a linear polyurethane resin are dissolved in an acrylate monomer.
[0004]
However, even if the above-mentioned adhesive has sufficient initial adhesive strength, the workability of the article after film adhesion is insufficient. Among the above adhesives, those containing a resin and those using high molecular weight oligomers increase the viscosity of the adhesive, and require an expensive coating machine for coating, or use a roll coater for coating. There is a disadvantage that the work is not successful. Further, when curing with an electron beam, since the curability of the adhesive is relatively poor, it is necessary to irradiate a large amount of electron beams. Therefore, there is a problem that the base film or the resin is deteriorated and the heat resistance is lowered, so that it cannot be used. In order to solve this problem, there is a method of blending polyfunctional oligomers and / or monomers, but the adhesive thus obtained has poor durability, and cannot withstand use at high temperatures and high humidity, for example.
By the way, optical discs such as compact discs, magneto-optical recording discs, DVDs, etc., which have been increasingly used in recent years, have a metal thin film layer formed by vapor deposition or sputtering on a transparent substrate such as polycarbonate. . This metal thin film layer easily deteriorates due to the influence of oxygen and moisture in the atmosphere, and is particularly susceptible to high temperature and high humidity. When bonding a substrate provided with this metal thin film layer to a transparent substrate, there is a demand for a bonding adhesive that can be protected with high reliability and has excellent durability.
[0005]
[Problems to be solved by the invention]
An object of this invention is to provide the active energy ray hardening-type adhesive composition excellent in sclerosis | hardenability, the adhesive force after hardening, workability, and durability.
[0006]
[Means for Solving the Problems]
As a result of intensive studies to solve the above-mentioned problems, the inventor has found that an adhesive composition containing di (meth) acrylate having a specific structure is curable, adhesive strength after curing, workability, and durability. It has been found that it has excellent properties and has achieved the above-mentioned problems.
[0007]
That is, this invention is an active energy ray hardening-type adhesive composition characterized by including the di (meth) acrylate shown by the said General formula (1).
A preferred embodiment of the present invention is a di (meth) acrylate (component A) having a structure represented by the general formula (1), and one (meth) acryloyl in the molecule represented by the general formulas (2) to (4). Group (meth) acrylate (B component), urethane (meth) acrylate and / or epoxy (meth) acrylate (C component) having a (meth) acryloyl group at both ends of the molecule, and photopolymerization initiator (D component) The ratio of the components (A) to (C) is 10 to 80% by mass of the component (A), 5 to 30% by mass of the component (B), and 5 to 85% by mass of the component (C). It is an active energy ray-curable adhesive composition obtained by blending 0.05 to 12 parts by mass of component (D) with respect to 100 parts by mass of the total amount of the mixture.
The present invention will be described in detail below.
In the present specification, acrylate or methacrylate is represented as (meth) acrylate, and acrylic acid and methacrylic acid are represented as (meth) acrylic acid.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
The di (meth) acrylate (component A) used in the present invention is a di (meth) acrylate having a norbornane skeleton represented by the following general formula (1).
[0009]
[Chemical formula 5]

[0010]
(However, in Formula (1), R < ₁ > is a hydrogen atom or a methyl group, R < ₂ > is an alkylene group, a and b are the integers of 0-5 each independently.)
The component (A) used in the present invention needs to be a trans form as shown in the above formula (1). Even if di (meth) acrylate having the same structure, in the case of a cis form, the hardness and durability of the obtained cured product are insufficient.
R ₂ is preferably an alkylene group having 1 to 4 carbon atoms such as a methylene group, an ethylene group or a propylene group. As a and b, it is particularly preferable that both a and b are 0.
[0011]
As a specific example of the component (A), in formula (1), R ₁ is a hydrogen atom, a and b are each 0 trans-norbornane dimethylol diacrylate, R ₁ is a methyl group, R ₂ is an ethylene group And a diacrylate of trans-norbornane dimethylol ethylene oxide 2 mol modified product in which a and b are each 1.
[0012]
In the adhesive composition of the present invention, in order to increase the flexibility of the composition, the skeleton is similar to the component (A) and has excellent compatibility with the following general formula (2), general formula (3), or general formula It is preferable to use together (meth) acrylate (B component) having one acryloyl group in the molecule represented by the formula (4).
[0013]
[Chemical 6]

[0014]
(However, in the (meth) acrylate having a dicyclopentadiene skeleton represented by the formula (2), R ₃ is a hydrogen atom or a methyl group, R ₄ is a methylene group or a group —CH ₂ CH ₂ O— or —CH _2. CH (CH ₃ ) O—, c is an integer of 0 to 4.)
[0015]
[Chemical 7]

[0016]
(However, in the (meth) acrylate having a tricyclodecane skeleton represented by the formula (3), R ₅ is a hydrogen atom or a methyl group, R ₆ is a methylene group or a group —CH ₂ CH ₂ O— or —CH _2. CH (CH ₃ ) O—, d is an integer of 0 to 4.)
[0017]
[Chemical 8]

[0018]
(However, in the (meth) acrylate having a norbornane skeleton represented by the formula (4), R ₇ is a hydrogen atom or a methyl group.)
[0019]
In this invention, (B) component which consists of at least 1 sort (s) among (meth) acrylate shown by Formula (2)-Formula (4) is the total amount of (A), (B), and a postscript (C) component 100. It is preferable that 5-30 mass parts is contained with respect to the mass part. When the component (B) is less than 5 parts by mass, sufficient flexibility cannot be obtained, and when it exceeds 30 parts by mass, the adhesive force is insufficient, which is not preferable. Instead of the component (B), a (meth) acrylate having one (meth) acryloyl group in another molecule such as methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, or the like is used. However, since the cohesive force of the adhesive is reduced, there is a possibility that the adhesive may be inadequate as a result.
[0020]
In addition to the components (A) and (B), the adhesive composition of the present invention is a urethane having (meth) acryloyl groups at both ends of the molecule for the purpose of imparting physical properties as a base resin of the adhesive ( It is preferable to use meth) acrylate and / or epoxy (meth) acrylate (C component) in combination.
[0021]
Specific examples of urethane (meth) acrylates include isocyanates (eg, tolylene diisocyanate, diphenylmethane diisocyanate, hexamethylene diisocyanate, xylylene diisocyanate, isophorone diisocyanate) and diols (eg, ethylene glycol, propylene glycol, hexamethylene glycol, polyethylene). It is a urethane (meth) acrylate having two (meth) acryloyl groups in the molecule, in which the polyurethane, which is an addition reaction product with glycol or the like, is used as a skeleton and (meth) acrylate is added to the molecular terminal. The preferable molecular weight of urethane (meth) acrylate is 500-4000. If the molecular weight is less than 500, the adhesive strength is insufficient. Conversely, if it exceeds 4000, a dilution monomer is required to reduce the viscosity of the adhesive, and these additions may reduce the physical properties of the adhesive. .
[0022]
A well-known thing can be used for epoxy (meth) acrylate. These are synthesized, for example, by a reaction between a glycidyl group-containing compound and (meth) acrylic acid. Examples of the glycidyl group-containing compound include bisphenol A type resin, bisphenol F type resin, bisphenol Z type resin, phenol novolac type epoxy resin, cresol novolac type epoxy resin and the like.
The proportion of the component (C) is preferably 5 to 85 parts by mass with respect to 100 parts by mass of the total amount of the components (A), (B) and (C). When the content is less than 5 parts by mass, the cohesive force as an adhesive and flexibility cannot be balanced, and the adhesive for the base film is insufficient. Conversely, if it exceeds 85 parts by mass, the strength as an adhesive may be insufficient.
[0023]
The adhesive composition of the present invention is cured by irradiation with active energy rays such as an electron beam, visible light, and ultraviolet rays. In order to obtain a resin sheet having a large film thickness, It is preferable to do.
When a visible light or ultraviolet curable composition is used, a photopolymerization initiator (component D) is added to the composition. (D) As a ratio in the case of mix | blending component, 0.05-12 mass parts is preferable with respect to 100 mass parts of total amounts of (A), (B), and (C) component, More preferably, it is 0.1. ˜2 parts by mass.
In addition, when setting it as an electron beam curing type, it is not necessarily required to mix | blend (D) component. Specific examples of the component (D) include benzoins such as benzoin, benzoin methyl ether and benzoin propyl ether; acetophenone, 2,2-dimethoxy-2-phenylacetophenone, 2,2-diethoxy-2-phenylacetophenone, 1, Acetophenones such as 1-dichloroacetophenone, 1-hydroxycyclohexyl phenyl ketone, 2-methyl-1- [4- (methylthio) phenyl] -2-morpholino-propan-1-one and N, N-dimethylaminoacetophenone; 2 Anthraquinones such as methyl anthraquinone, 1-chloroanthraquinone and 2-amylanthraquinone; 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, 2-chlorothioxanthone and 2,4-diisopropylthioxa Thioxanthones such as Tone; ketals such as acetophenone dimethyl ketal and benzyl dimethyl ketal; benzophenone, methylbenzophenone, 4,4′-dichlorobenzophenone, 4,4′-bisdiethylaminobenzophenone, Michler's ketone and 4-benzoyl-4′-methyl Benzophenones such as diphenyl sulfide; and 2,4,6-trimethylbenzoyldiphenylphosphine oxide.
Component (D) may be used alone or in combination of two or more.
A photosensitizer can be used in combination with the component (D) as necessary. Examples of the photosensitizer include N, N-dimethylaminobenzoic acid ethyl ester, N, N-dimethylaminobenzoic acid isoamyl ester, triethylamine, and triethanolamine.
[0024]
In the adhesive composition of the present invention, as an additional component, for the purpose of enhancing the adhesion to a metal material or the like, for example, a phosphate group such as (meth) acryloyloxyethyl phosphate or bis (meth) acryloyloxyethyl phosphate is added. It is also possible to add a compound to be contained. However, since these are not very compatible with the adhesive composition, it is preferable not to exceed 10 parts by mass with respect to 100 parts by mass of the total amount of the components (A), (B) and (C). . Moreover, a silane coupling agent, a polymerization inhibitor, etc. can also be added as needed.
[0025]
Examples of the silane coupling agent include γ- (2-aminoethyl) aminopropyltrimethoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane, and the like.
[0026]
Examples of the polymerization inhibitor include hydroquinone, hydroquinone monomethyl ether, t-butylcatechol, p-benzoquinone and the like.
[0027]
The amount of the silane coupling agent, polymerization inhibitor, etc. used is preferably in the range of up to 10 parts by mass with respect to 100 parts by mass of the total amount of components (A), (B) and (C).
[0028]
In the adhesive composition of the present invention, when curing with an electron beam, it is not necessary to use the component (D), and when using other active energy beams, each component (A) to It can be obtained by mixing (D).
[0029]
As a method of using the adhesive composition of the present invention, after applying this composition to a substrate such as a polycarbonate provided with a metal thin film layer or the like, the substrate is covered with a polycarbonate or the like for bonding, and active energy rays are applied. Irradiate.
Examples of the base material include molded resin processed products such as polycarbonate and polymethyl methacrylate, polycarbonates and films provided with metal thin films, and the like.
[0030]
【Example】
The present invention will be described below with reference to examples and comparative examples, but the present invention is not limited by the following examples. In the following, all parts represent parts by mass.
[0031]
Examples 1 to 4 and Comparative Examples 1 and 2
In the composition shown in Table 1, di (meth) acrylate (A component) represented by formula (1), (meth) acrylate (B component) having one (meth) acryloyl group in the molecule, urethane (meta ) Acrylate and / or epoxy (meth) acrylate (C component) and a photopolymerization initiator (D component) were mixed to prepare an active energy ray-curable adhesive composition. This adhesive composition was applied to a PC substrate and a PC substrate on which aluminum was vapor-deposited with a thickness of 5 μm using a spin coater. Further, polycarbonate was put on the top. Next, ultraviolet irradiation was performed 10 times under the condition of 0.8 J / cm ² with a high-pressure mercury lamp having a conveyor speed of 5 m / min and an output of 160 W / cm.
[0032]
The following items were evaluated using the test materials with the cured coating film thus obtained. The results are shown in Table 1. The results of Examples 2 to 4 and Comparative Examples 1 and 2 are also shown in Table 1.
[0033]
○ Evaluation (1) Adhesion test After applying the composition onto the substrate, the test piece of polycarbonate (made by Nippon Test Panel Industry Co., Ltd .: 3.0mm x 25mm x 100mm) is applied to the active energy beam. The tensile shear bond strength was measured.
(2) Durability test The cured product obtained on the PC substrate on which aluminum was deposited was allowed to stand for 24 hours in 80 ° C. warm water, and then observed for abnormalities in the appearance of the aluminum substrate. Was marked with ◯, and the appearance changed with x.
[0034]
[Table 1]

[0035]
In addition, the symbol in Table 1 has the following meaning.
t-NDMDA: trans-norbornane dimethylol diacrylate FA-513A: manufactured by Hitachi Chemical Co., Ltd. Tricyclodecanyl acrylate TCDMA: tricyclodecane methylol acrylate FA-511A: manufactured by Hitachi Chemical Co., Ltd. dicyclopentenyl acrylate NMA : Norbornane methylol acrylate M-1310: Urethane acrylate M-1600, manufactured by Toagosei Co., Ltd .: Urethane acrylate epoxy ester 3002A, manufactured by Toagosei Co., Ltd. Propylene oxide 2 mol adduct diglycidyl ether of bisphenol A Acrylic acid adduct HCPK: 1-hydroxycyclohexyl phenyl ketone BDK: benzyl dimethyl ketal M-240: manufactured by Toagosei Co., Ltd. Polyethylene glycol diacrylate M-408: Toago Ditrimethylolpropane tetraacrylate manufactured by Synthetic Co., Ltd. [0036]
As is clear from the examples, the active energy ray-curable adhesive composition of the present invention has good adhesion, and is excellent in the durability of the cured film and the protective effect of the substrate under high temperature and high humidity. Met. On the other hand, in the adhesion test of Comparative Example 2, the test piece did not adhere at all, and the tensile shear strength could not be measured. Thus, in what was shown in the comparative example, sufficient adhesive force and durability cannot be obtained.
[0037]
【The invention's effect】
The adhesive composition of the present invention exhibits excellent adhesion to plastics such as polycarbonate, aluminum, and the like by curing with active energy rays such as ultraviolet rays, visible rays, and electron beams. In addition, it exhibits an excellent effect for stable adhesion and substrate protection even under high temperature and high humidity. The active energy ray-curable adhesive composition obtained by the present invention is particularly suitable for bonding to plastics and metals, such as adhesives for optical discs, particularly DVDs, etc. It is useful as an agent.

Claims (4)

An active energy ray-curable adhesive composition comprising di (meth) acrylate (A component) represented by the following general formula (1).

(In general formula (1), R ₁ is a hydrogen atom or a methyl group, R ₂ is an alkylene group, and a and b are each independently an integer of 0 to 5.) Along with the component (A), a (meth) acrylate (component B) having one (meth) acryloyl group in the molecule represented by the following general formula (2), general formula (3) or general formula (4) An active energy ray-curable adhesive composition comprising:

(In the general formula (2), R ₃ is a hydrogen atom or a methyl group, R ₄ is a methylene group or a group —CH ₂ CH ₂ O— or —CH ₂ CH (CH ₃ ) O—, and c is an integer of 0 to 4. .)

(In the general formula (3), R ₅ is a hydrogen atom or a methyl group, R ₆ is a methylene group or a group —CH ₂ CH ₂ O— or —CH ₂ CH (CH ₃ ) O—, and d is an integer of 0 to 4. .)

(In the general formula (4), R ₇ is a hydrogen atom or a methyl group.) Along with the (A) component and the (B) component, urethane (meth) acrylate or epoxy (meth) acrylate having a (meth) acryloyl group at both ends of the molecule and having a number average molecular weight of 500 to 4000 is included. An active energy ray-curable adhesive composition characterized by the above. Along with the component (A) and the component (B), urethane (meth) acrylate and epoxy (meth) acrylate having a (meth) acryloyl group at both ends of the molecule and having a number average molecular weight of 500 to 4000 are included. An active energy ray-curable adhesive composition characterized by the above.