JP4273739B2 - RESIN COMPOSITION FOR DIELECTRIC HEAT-ADJUSTING, HOT-MELT ADHESIVE, ADHESIVE METHOD FOR ADHESIVE MATERIAL, ADHESIVE RESIN COMPOSITION AND ADHESIVE COMPOSITE USED AS A HOT-MELT ADHESIVE ADHESIVE - Google Patents

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【０１８０】
【表２】

【０１８１】
ここで、表１および表２において、
＊１：ＰＯ−１は、シラン変性Ｇ１９７（ポリエチレン共重合ブレンド物からなるポリオレフィン系樹脂、クレハエラストマー（株）製、融点１０５℃）を表わす。
＊２：ＰＯ−２は、シラン変性Ｇ１０１９（ポリエチレン共重合ブレンド物からなるポリオレフィン系樹脂、クレハエラストマー（株）製、融点１２０℃）を表わす。
＊３：Ｆｅ１００は、ＡＳＣ１００（鉄粉、ヘガネス社製、平均粒径１００μｍ、体積抵抗率（ρ）１．４×１０^-5Ω・ｃｍ）を表わす。
＊４：Ｆｅ２００は、ＫＩＰ３００（鉄粉、川崎製鉄（株）製、平均粒径２００μｍ、体積抵抗率（ρ）１．６×１０^-6Ω・ｃｍ）を表わす。
＊５：Ｃｕ１００は、ＣＥ−６（銅粉、福田金属箔粉工業（株）製、平均粒径１００μｍ、体積抵抗率（ρ）１．７×１０^-6Ω・ｃｍ）を表わす。
＊６：ＣＦは、ＨＴＡ（炭素繊維、東邦レーヨン（株）製、平均長さ３ｍｍ、体積抵抗率（ρ）１．５×１０^-3Ω・ｃｍ）を表わす。
＊７：ＰＯ−３は、エバフレックスＥＥＡ Ａ７０９（エチレンエチルアクリレート樹脂からなるポリオレフィン系樹脂、三井・デュポンポリケミカル（株）製、融点５６℃）を表わす。
＊８：ＰＯ−４は、ＴＰＸ（ポリメチルペンテンからなるポリオレフィン系樹脂、三井石油化学（株）製、融点２６５℃）を表わす。
＊９：ＳＧＦ０５は、日東紡績（株）製の体積抵抗率１０¹²Ω・ｃｍのミルドファイバーを表わす。
【０１８２】
＜分析および評価用サンプルの作製＞
まず、実施例１〜１２および比較例１〜４において得られたホットメルト接着剤のペレットを用いて、下記の成形方法を用いてそれぞれ接着剤プレートを作製し、また特性分析および性能評価に必要となる被接着材プレートを下記の成形方法を用いて作製した。
【０１８３】
（ｉ）接着剤プレートの成形
実施例１〜１２および比較例１〜４において得られたホットメルト接着剤のペレットを、バレルをホッパー側から１８０−２００−２００℃に温度調節した射出成形機に投入して、４０℃に温度調節されたテストピース金型に射出し、それぞれ１００×１００×１ｍｍ、１００×１００×３ｍｍの二種類のサイズの接着剤プレートを得た。
【０１８４】
（ｉｉ）被接着材プレートの成形
１４０℃にて３時間乾燥した３０質量％ガラス繊維強化変性ポリブチレンテレフタレート（東洋紡績（株）製、ＥＭＣ４３０）のペレットを、バレルをホッパー側から２５０−２６０−２６０℃に温度調節した射出成形機のホッパーに投入して、ＡＳＴＭ Ｄ６３８記載のＴＹＰＥ Ｉ（厚み３．２ｍｍのダンベル型）の引張テストピースを成形した。
【０１８５】
＜特性分析と性能評価＞
次に、上記のようにして得られた、実施例１〜１２および比較例１〜４のホットメルト接着剤からなる接着剤プレート、上記の被接着材プレートおよび表３に示すその他の各種被接着材プレートを用いて、下記の分析方法および評価方法に従って、実施例１〜１２および比較例１〜４において得られたホットメルト接着剤の性能評価を行なった。結果を表１〜表３に示す。
【０１８６】
（ｉ）誘電正接および誘電損失係数の測定
まず、実施例１〜１２および比較例１〜４のホットメルト接着剤からなる接着剤プレートのうち、１００×１００×３ｍｍのサイズの接着剤プレートから８×８×３ｍｍのサイズの試験片を切り出した。次に、高周波誘電加熱装置（パール工業（株）製、インピーダンスアナライザー）に接続された端子面積Ｄｓが５ｃｍ²の導体端子間に、当該試験片を挟んで固定した。そして、当該試験片に周波数４０ＭＨｚの高周波電荷Ｑを２３℃条件下で与えて端子間の電位差Ｖを測定し、端子間の電位差Ｖから静電容量Ｃｓと誘電正接（ｔａｎδ）を測定した。
【０１８７】
また、真空中の誘電率ε₀を８．８５×１０^-14Ｆ／ｃｍとして下記の式（Ｉ）より誘電損失係数ε・ｔａｎδを求めた。
ε・ｔａｎδ＝Ｃｓ×Ｄｓ／（ε₀×Ｓ）・・・（Ｉ）
（ｉｉ）接着強度
上記のようにして得られたガラス繊維強化ポリブチレンテレフタレート樹脂成形品（東洋紡績（株）製、ＥＭＣ４３０）からなる被接着材プレートを、長さ方向の中央にて切断し、１２．７×２５．４×３．２ｍｍの被接着材プレート片を得た。
【０１８８】
次いで、実施例１〜１２および比較例１〜４のホットメルト接着剤からなる接着剤プレートのうち、１００×１００×１ｍｍのサイズの接着剤プレートから１２．７×２５．４×３ｍｍのサイズの試験片を切出して、当該被接着材プレート片の直線部分に重ね合わせた。
【０１８９】
そして、図２に示すように、得られた接着剤プレート３ａ，３ｂ−被接着材プレート５ａ，５ｂの複合体を重ねて、３３×１００×３ｍｍのガラス板１の両端に直線状に、軸を合わせた状態で固定し、当該接着強度評価用複合体１００を得た。
【０１９０】
続いて、高周波誘電加熱装置（パール工業（株）製、商品名インピーダンスアナライザー）に接続された端子面積Ｄｓが５ｃｍ²の導体端子間に、当該接着強度評価用複合体１００を挟んで固定した。そして、当該接着強度評価用複合体を２０ｍｍφのエアシリンダーで２ｋｇ／ｃｍ ² 加圧した状態で、当該接着強度評価用複合体に、発振時間としてそれぞれ表１〜３において選ばれる１分、５分または２０分間にわたり周波数４０ＭＨｚの高周波電圧を印加して当該接着強度評価用複合体を加熱後、エアブローで１分冷却して接着強度評価用試験片とした。
【０１９１】
こうして得られた接着強度評価用試験片を２３℃、５０％ＲＨに調節された試験室に５時間以上放置した。そして、図２に示すように、５０℃に温度調節された恒温槽を備えた万能引張試験機ＵＴＭＩ型（（株）オリエンテック製）のチャックに、接着強度評価用複合体１００を引張剪断変形軸が垂直になるような状態で固定し、５ｍｍ／分の変形速度で引張方向７ａ，７ｂに引張剪断することにより、当該接着強度評価用試験片の５０℃における接着強度を測定した。
【０１９２】
表１〜表２に示される結果から、実施例１〜１２のホットメルト接着剤は、融点が８０〜２００℃の範囲にあるポリオレフィン系樹脂と、体積抵抗率が１０^-2Ω・ｃｍ以下の導電物質とを含有しており、樹脂組成物全体に対する当該導電物質の含有量が１〜３０容量％の範囲にあるため、誘電正接が０．０３以上となっており、その結果５０℃と比較的高温における接着強度も比較例１〜４のホットメルト接着剤に比べて優れていることがわかる。
【０１９３】
＜実施例１３〜１８＞
本発明のホットメルト接着剤について、他の被接着材との接着強度を調べるために、実施例３のホットメルト接着剤から得られる上記の接着剤プレートを、表３に示した各種被接着材プレート上面側と下面側との間に挿置して、上記の特性分析と性能評価の項目における（ｉｉ）接着強度の測定方法と同様にして、実施例３のホットメルト接着剤と他の被接着材との接着強度およびを測定した。結果を表３に示す。
【０１９４】
【表３】

【０１９５】
ここで、表３において、セラミック板は東芝セラミックス（株）製電磁調理器用セラミックス板、アルミ板は古河アルミニウム工業（株）製サッシ用アルミニウム板、ポリアミド樹脂板は東洋紡績（株）製東洋紡ナイロンＴ−４０２（ガラス繊維強化ポリアミド樹脂）からなる板、ＰＰＳ板は東洋紡績（株）製東洋紡ＰＰＳＴＳ４０１（ガラス繊維強化ポリフェニレンサルファイド樹脂）からなる板を表わす。また、サイズはいずれも１２×１５０×５ｍｍである。
【０１９６】
表３に示される結果より、実施例３のホットメルト接着剤は、ガラスおよびガラス繊維強化ポリブチレンテレフタレート樹脂のみならず、幅広い被接着材に対して優れた接着強度を有することがわかる。
【０１９７】
＜被接着用樹脂組成物＞
以下、別の実施例を挙げて本発明の被接着用樹脂組成物をより詳細に説明するが、本発明はこれらに限定されるものではない。
【０１９８】
＜実施例２１〜３４、比較例２１〜３０＞
まず、表４および表５に示す樹脂、改質材、無機充填材の組合せに基づいて、それらの所定量（質量部）を計量後、予備混合した。この予備混合体を、それぞれシリンダー温度をＴｍ＋３０℃に調節した直径３０ｍｍφの同方向２軸押出機のホッパーに投入し、スクリュー回転数１００ｒｐｍにて溶融混練してペレットを得た。得られた各々のペレットのうち、ポリエステル系樹脂および／またはポリフェニレンサルファイド系樹脂を含有するペレットは１４０℃で３時間、ポリアミド系樹脂を含有するペレットは１２０℃で２時間、ポリアセタール系樹脂および／またはポリオレフィン系樹脂を含有するペレットは８０℃で１時間乾燥し、評価用サンプルを得た。
【０１９９】
そして、下記の特性分析と性能評価の方法により得られた評価用サンプルの性能を評価した。その結果を併せて表４および表５に示す。
【０２００】
【表４】

【０２０１】
【表５】

【０２０２】
表４および表５中の略号は次の通りである。
ＰＢＴ：ポリブチレンテレフタレート（東洋紡績（株）製、バイロペットＥＭＣ７００、１ＭＨｚにおける誘電正接：０．０４、４０ＭＨｚにおける誘電正接：０．０３）
ＰＥＴ：ポリエチレンテレフタレート（東洋紡績（株）製、バイロペットＥＭＣ５００−０１、１ＭＨｚにおける誘電正接：０．０３、４０ＭＨｚにおける誘電正接：０．０３）
ＰＯＭ：ポリオキチメチレン（ポリプラスチックス（株）製、ジュラコンＭ９０Ｓ、１ＭＨｚにおける誘電正接：０．００６、４０ＭＨｚにおける誘電正接：０．００５）
ＰＡ６：ポリアミド６（東洋紡績（株）製、東洋紡ナイロンＴ８００、１ＭＨｚにおける誘電正接：０．０９、４０ＭＨｚにおける誘電正接：０．０８）
ＰＰ：ポリプロピレン（（株）グランドポリマー製、Ｅ７０００、１ＭＨｚにおける誘電正接：０．００２、４０ＭＨｚにおける誘電正接：０．００３）
ＲＡ：エポキシ変性ポリエチレン（日本ポリオレフィン（株）製、レキスパールＲＡ３１５０）
ＭＰ：無水マレイン酸変性ポリプロピレン（グランドポリマー（株）製、ＭＭＰ００６）
ガラス繊維：旭ファイバーグラス（株）製、０３ＪＡ４２９
ウイスカー：６チタン酸カリウム（大塚化学（株）製、テイスモーＤ）
ＭＷ：タルク（林化成（株）製、＃５０００Ａ）
ＩＯ：アイオノマー樹脂（三井・デユポンポリケミカル（株）製、ハイミラン１７０７）
ＭＤ：アルキルジベンジリデンソルビトール（新日本理化（株）、ゲルオールＭＤ）
＜特性分析と性能評価＞
次に、上記のようにして得られた、実施例２１〜３４および比較例２１〜３０の被接着用樹脂組成物のペレットを用いて、下記の分析方法および評価方法に従って、実施例２１〜３４および比較例２１〜３０において得られた被接着用樹脂組成物のペレットの性能評価を行なった。結果を表４および表５に示す。
【０２０３】
（ｉ)融点および結晶化温度
まず、被接着用樹脂組成物のペレットから１０ｍｇサンプルを切削採取しアルミパンに封入する。次いで、切削採取したサンプルをＤＳＣ（示差走査熱量計）の試料容器にセットする。そして、窒素ガス６０ｃｍ³／分を流しながら、２０℃／分の昇温速度にて昇温するのに必要な熱量の標準側との差を自動記録した。得られた記録に基づいて、吸熱ピーク温度を融点（Ｔｍ）とした。その後、Ｔｍより３０℃高い温度まで昇温して５分間保持した。続いて、１０℃／分の降温速度にて降温し、標準側との熱量差を自動記録し、発熱ピーク温度を結晶化発熱ピーク温度（Ｔｃ）とした。
【０２０４】
（ｉｉ）曲げ強度
溶融樹脂温度がＴｍ＋２０℃になるように設定された射出成形機により被接着用樹脂組成物のペレットを溶融した後に、表面温度が５０℃に温度調節された金型を使用して、厚さ６．４ｍｍ×幅１２．７ｍｍ×長さ１２７ｍｍの短冊をエッジゲートにより、射出時間１５秒、冷却１５秒にて射出成形後、１４０℃で１時間熱処理をして曲げ試験片とした。
【０２０５】
この試験片を２３℃、ＲＨ５０％の試験室にて２０時間保管後、スパン長１００ｍｍ、クロスヘッド速度３ｍｍ／ｍｉｎに設定した万能引張試験機によりＡＳＴＭ Ｄ７９０に準じて曲げ試験を行い、曲げ強度を計算により求めた。
【０２０６】
（ｉｉｉ）接着強度
溶融樹脂温度がＴｍ＋２０℃になるように設定された射出成形機により被接着用樹脂組成物のペレットを溶融した後に、表面温度が５０℃に温度調節された試験片金型を使用して、ＡＳＴＭ Ｄ６３８規定のＴＹＰＥ １成形品を射出時間１５秒、冷却１５秒にて射出成形後、１４０℃で１時間熱処理して被接着材プレートを得た。この被接着材プレートを長さ方向の中央部で切断した。
【０２０７】
そして、図２に示すように、この切断された被接着材プレート５ａ，５ｂの直線部分１２．７ｍｍ×２５．４ｍｍに、１００ｍｍ×１００ｍｍ×１ｍｍのホットメルト接着剤プレートから１２．７ｍｍ×２５．４ｍｍの接着剤プレート３ａ，３ｂをカットして重合わせた。このラップ部分を、３３ｍｍ×１００ｍｍ×３ｍｍのガラス板１の両端に直線状にセットした。
【０２０８】
そして、これを２０ｍｍφのエアシリンダーで０．２ＭＰａ加圧した状態で、高周波誘電加熱装置（パール工業（株）製）にて1分間加熱後、０〜３分間の範囲で冷却時間を変えた試験片を作製し、接着強度評価用複合体１００とした。
【０２０９】
次いで、接着強度評価用複合体１００を２３℃、５０％ＲＨに調節された試験室に５時間以上放置した。続いて、図２に示すように、万能引張試験機ＵＴＭＩ型（（株）オリエンテック製）のチャックに、ガラス板１の両端に接着した、被接着材プレート５ａ，５ｂ−接着剤プレート３ａ，３ｂからなる接着強度評価用複合体１００をセットし、５ｍｍ／分の変形速度で引張方向７ａ，７ｂに向け引張せん断することにより、５０℃における接着強度を測定した。
【０２１０】
そして、接着後の冷却過程でのズレが発生すると、被接着材間の密着性が低下し接着強度が低下する現象に基づき、接着強度の冷却時間変化からズレが発生しない必要冷却時間を判断した。
【０２１１】
表４および表５に示されるように、実施例２１〜３４の被接着用樹脂組成物においては、短時間の冷却時間で、ホットメルト接着剤との優れた接着強度が得られているのに対し、比較例２１〜３０の被接着用樹脂組成物においては、長時間の冷却時間を設けても、ホットメルト接着剤との優れた接着強度が得られないことがわかる。
【０２１２】
＜接着複合体およびその解体方法＞
以下、さらに別の実施例を挙げて本発明の接着複合体および接着複合体の解体方法をより詳細に説明するが、本発明はこれらに限定されるものではない。
【０２１３】
＜各種実験材料の作製＞
実施例および比較例中における各種材料は以下の方法により作製した。
【０２１４】
（ｉ）被接着材プレートの作製
３０％質量のガラス繊維強化ポリブチレンテレフタレート（東洋紡績（株）製、ＥＭＣ４３０）を加工して、厚さ３.２ｍｍ ＡＳＴＭ Ｄ６３８ ＴＹＰＥ１の被接着材プレートを作製した。
【０２１５】
（ｉｉ）ガラス板の作製
厚さ３．４ｍｍの自動車の窓用ガラスを３０ｍｍ×８０ｍｍに切断し、試験用ガラス板を作製した。
【０２１６】
（ｉｉｉ）ポリオレフィン系接着剤Ｉの作製
シラン変性Ｇ１９７（ポリエチレン共重合ブレンド物からなるポリオレフィン系樹脂、クレハエラストマー（株）製、融点１０５℃）に、粒径１００μｍの鉄粉（ヘガネス社製、ＡＳＣ１００）を６０質量％配合して作製した。
【０２１７】
（ｉｖ）ポリオレフィン系接着剤ＩＩの作製
シラン変性Ｇ１９７（ポリエチレン共重合ブレンド物からなるポリオレフィン系樹脂、クレハエラストマー（株）製、融点１０５℃）に、炭素繊維（東邦レーヨン（株）製、ＨＴＡ、平均長さ３ｍｍ）を１０質量％配合して作製した。
【０２１８】
（ｖ）ポリオレフィン系接着剤ＩＩＩの作製
シラン変性Ｇ１９７（ポリエチレン共重合ブレンド物からなるポリオレフィン系樹脂、クレハエラストマー（株）製、融点１０５℃）をそのまま用いた。
【０２１９】
（ｖｉ）接着剤シートの作製
上記のポリオレフィン系接着剤Ｉ、ＩＩ、ＩＩＩのバレルを、それぞれホッパー側から１８０−２００−２００℃に温度調整した射出成形機に投入して、４０℃に温度調節されたテストピース金型に射出し、それぞれ１００ｍｍ×１００ｍｍ×１ｍｍ、１００ｍｍ×１００ｍｍ×３ｍｍの二種類のサイズの接着剤シートを作製した。
【０２２０】
＜実施例４１〜４３、比較例４１〜４５＞
表６および表７に示す組合せからなる、実施例４１〜４３、比較例４１〜４５の接着複合体を作製し、それぞれの接着複合体の有する特性と性能について、下記の特性分析と性能評価の方法により測定した。その結果を、表６および表７に併せて示す。
【０２２１】
ここで、比較例４１〜４５については、誘電加熱により解体することができなかった。そのため、比較のために、比較例４２〜４５の加熱炉１４０℃における解体時間を表７に示した。
【０２２２】
【表６】

【０２２３】
【表７】

【０２２４】
＜特性分析と性能評価＞
次に、上記のようにして得られた、実施例４１〜４３および比較例４１〜４５の接着複合体を用いて、下記の分析方法および評価方法に従って、実施例４１〜４３および比較例４１〜４５において得られた接着複合体の性能評価を行なった。結果を表６および表７に示す。
【０２２５】
（ｉ）誘電正接の測定
まず、１００ｍｍ×１００ｍｍ×３ｍｍのポリオレフィン系接着剤Ｉ、ＩＩ、ＩＩＩのシートから８ｍｍ×８ｍｍ×３ｍｍのサイズの試験片を切出した。次に、高周波誘電加熱装置（パール工業（株）製、インピーダンスアナライザー）に接続された端子面積Ｄｓが５ｃｍ²の導体端子間に、当該試験片を挟んで固定した。そして、当該試験片に周波数４０ＭＨｚの高周波電荷Ｑを２３℃条件下で与えて端子間の電位差Ｖを測定し、端子間の電位差Ｖから誘電正接を測定した。
【０２２６】
（ｉｉ）接着強度の測定
図２に示すように、被接着材プレート５ａ，５ｂの直線部分の１２．７ｍｍ×２５．４ｍｍに、厚さ１ｍｍのポリオレフィン系接着剤Ｉ、ＩＩ、ＩＩＩのシートから１２.７ｍｍ×２５．４ｍｍの接着剤プレート３ａ，３ｂをカットして重合わせた。このラップ部分を３０ｍｍ×８０ｍｍのガラス板１の両端に直線状にセットした。これをクリップ（（株）ライオン事務器製、ＮＯ．１１１）に挟み、１４０℃で２０分間処理して、接着強度評価用複合体１００を作製した。
【０２２７】
次いで、図２に示すように、加熱炉付テンシロンＵＴＭ１型のチャックに、上記の接着強度評価用複合体１００をセットし、５ｍｍ／分の速度で引張方向７ａ，７ｂの方向に引張せん断することにより接着強度を測定した。なお、試験温度は２３℃にて実施した。
【０２２８】
（ｉｖ）誘電加熱解体時間および１４０℃解体時間の測定
誘電加熱解体時間は、高周波誘電加熱装置（パール工業（株）製、インピーダンスアナライザー）に接続された、端子面積が５ｃｍ²の導体端子間に、表６および表７に示した各種接着複合体を挿入し、周波数４０ＭＨｚの高周波電圧を２３℃条件下で、いろいろな発振時間で印加し、接着層を溶融させ、被接着材を剥離するまでの時間を測定して求めた。また、１４０℃解体時間は、表７に示した各種接着複合体を１４０℃の高温槽に設置して、接着層を溶融させ、被接着材を剥離するまでの時間を測定して求めた。
【０２２９】
表６および表７に示されるように、実施例４１〜４３の接着複合体は、優れた接着強度を有する一方で、短時間の誘電加熱解体時間で接着層を溶融させ被接着材を剥離可能であるのに対し、比較例４１〜４５の接着複合体は、１４０℃の高温で処理しても、非常に長時間の誘電加熱解体時間を経てようやく接着層を溶融させ被接着材を剥離可能であることがわかる。すなわち、従来の加熱炉１４０℃における解体に比較し、本発明の実施例による接着複合体の解体時間は大幅に短縮されていることがわかる。
【０２３０】
今回開示された実施の形態および実施例はすべての点で例示であって制限的なものではないと考えられるべきである。本発明の範囲は上記した説明ではなくて特許請求の範囲によって示され、特許請求の範囲と均等の意味および範囲内でのすべての変更が含まれることが意図される。
【０２３１】
【発明の効果】
上記の結果より、本発明の誘電加熱接着用樹脂組成物は、非常に短時間の高周波電圧の印加により加熱溶融させることができ、比較的高温でも優れた接着強度を有する。そのため、本発明の誘電加熱接着用樹脂組成物は、高周波電圧を印加することにより加熱溶融する性質を有するホットメルト接着剤のバインダとして好適に使用可能である。
【０２３２】
また、本発明のホットメルト接着剤は、非常に短時間の高周波電圧の印加により加熱溶融させることができ、比較的高温でも優れた接着強度を有する。そのため、本発明のホットメルト接着剤を用いることにより、従来のホットメルトタイプ接着剤では必要とされていた加熱炉を用いる必要がなく、ホットメルト接着剤を用いる製品の製造設備のコンパクト化、製造工程の簡略化が可能となり、製造ラインの生産性を著しく高めることができる。また、本発明のホットメルト接着剤をシート状に成形して用いることにより、大型部材同士の接着工程においても、非常に短時間の高周波電圧の印加により均一で優れた接着強度を得ることができる。
【０２３３】
そして、本発明の被接着材同士の接着方法は、非常に短時間の高周波電圧の印加により優れた接着強度を実現することができる。そのため、本発明の被接着材同士の接着方法を用いることにより、従来のホットメルトタイプ接着剤を用いた接着方法では必要とされていた加熱炉を用いる必要がなく、ホットメルト接着剤を用いた接着方法により製造される製品の製造設備のコンパクト化、製造工程の簡略化が可能となり、製造ラインの生産性を著しく高めることができる。また、本発明の被接着材同士の接着方法を用いることにより、大型部材同士の接着工程においても、非常に短時間の高周波電圧の印加により均一で優れた接着強度を得ることができる。
【０２３４】
また、上記の結果より、本発明の被接着用樹脂組成物は、ホットメルト接着剤による接着の際に、ホットメルト接着剤の加熱により溶融あるいは軟化し難く、かつ短時間に再硬化して優れた接着性を示す、ホットメルト接着剤の被接着材として用いられる被接着用樹脂組成物である。
【０２３５】
さらに、上記の結果より、本発明の接着複合体は、加熱炉を使用することなく高周波電圧の印加により短時間に解体ができ、被接着体の材質が良好に再使用できる、高周波電圧を印加することにより解体可能な、接着複合体である。
【０２３６】
そして、上記の結果より、本発明の接着複合体の解体方法は、上記の接着複合体の接着部分のみを効率的に加熱することにより、解体時におけるエネルギー、時間および労力を省力化することができる、接着複合体の解体方法である。
【０２３７】
したがって、本発明の接着複合体の解体方法は、加熱炉を使用せず、また短時間に解体が可能なうえに、接着層のみが選択的に加熱溶融されるため、解体に要するエネルギーの省力化が実現できる。また、本発明の接着複合体の解体方法は、材料の破損や劣化の度合いが低いため、大型部材の回収が可能となり、産業界に寄与すること大である。
【図面の簡単な説明】
【図１】 本発明の接着複合体の解体方法の概略を示すステップ図である。
【図２】 接着複合体の接着強度の測定方法の一例を示す概略図である。
【符号の説明】
１ ガラス板、３ａ，３ｂ 接着剤プレート、５ａ，５ｂ 被接着材プレート、７ａ，７ｂ 引張方向、１００ 接着強度評価用複合体。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a resin composition for dielectric heating adhesion. More specifically, the present invention can be heated and melted by applying a high-frequency voltage for a short time without using a heating furnace, and is the same or different material selected from the group consisting of glass, ceramics, metals, and resins. The present invention relates to a resin composition for dielectric heating adhesion that is excellent in adhesive strength at a relatively high temperature when used for bonding between each other.
[0002]
The present invention also relates to a hot melt adhesive containing the resin composition for dielectric heating adhesion of the present invention. Furthermore, the present invention relates to a method for bonding an adherend using the resin composition for dielectric heating bonding of the present invention.
[0003]
And this invention relates to the resin composition for to-be-adhered used as a to-be-adhered material of the hot-melt-adhesive of this invention.
[0004]
The present invention also relates to an adhesive composite comprising the hot melt adhesive of the present invention and an adherend. Furthermore, the present invention relates to a method for disassembling the adhesive composite of the present invention.
[0005]
[Prior art]
In recent years, the progress of the function of adhesives has been remarkable, and adhesives are used in many fields such as electricity, machinery, civil engineering, architecture, wood, paper, textiles, and chemistry. In addition, with the advancement of the function of adhesives, adhesives that have been used as secondary materials in the past have recently been used for bonding main materials of important structural parts. For example, adhesives are often used in places where reliability is required, such as bonding between brake linings of automobiles and bonding of honeycomb structures for aircraft lightweight reinforcement measures.
[0006]
Using adhesives instead of screws, nails, welding, etc., which have been used for general purposes, can simplify the manufacturing process and often achieve significant cost savings. If an adhesive is used, the product can be reduced in weight. And if this weight reduction by adhesives is applied to automobiles, railway vehicles, airplanes, etc., it will indirectly contribute to labor saving of motive energy, and moreover, carbon dioxide that may indirectly cause global environmental problems This will contribute to the reduction of emissions. Therefore, the importance of adhesives is increasing in each industrial field.
[0007]
As described above, the same or different materials selected from the group consisting of large glass, ceramics, metals, and resins, such as those used in the fields of automobiles, railway vehicles, aircraft, civil engineering and architecture In the past, in order to improve the adhesion and / or durability of the bonding, a primer is applied to the surface of the adherend before applying the adhesive, and the primer is dried and / or cured. Later, an adhesive was applied to the surface of the primer coating, and the adhesive was often dried and / or cured to bond the adherends together.
[0008]
However, when chemical pretreatment of the adherend is performed using a primer, it takes a long time to dry the solvent contained in the primer and / or adhesive and to cure the primer and / or adhesive. There was a problem, and there was a problem that the use of solvents adversely affects the work environment and the global environment.
[0009]
Therefore, in order to solve the above problems, hot melt adhesives have been widely used industrially recently. Hot melt adhesives contain little or no solvent and therefore have little adverse effect on the work environment and the global environment, have low risk of ignition, and are easy to handle because they are solid at room temperature. In addition, it can be said to be an adhesive suitable for high-speed and large-scale processing by automation since it solidifies as soon as it is left after melting and bonding.
[0010]
However, a general hot melt adhesive has a drawback that the required performance is often not obtained because of low adhesive strength at high temperatures. In addition, when a high-temperature type hot melt adhesive is used, a large heating furnace is necessary because the melting point of the adhesive is high, and thus the manufacturing cost must be increased accordingly. In addition, when a hot melt adhesive is used, a cycle of a heating process and a cooling process is necessary, and there are major obstacles in industrialization, and there is no choice but to put it into practical use.
[0011]
Therefore, in order to obtain an adhesive having the advantages of the hot melt adhesive as described above and overcoming the disadvantages as described above, many efforts have been made to develop a hot melt adhesive in various fields. Yes. The adhesive containing the resin composition for dielectric heating adhesion in the present invention is a kind of hot melt adhesive, and is heated and melted by applying a high frequency voltage in a state where the adhesive is interposed between the adherends. Then, it has a function of bonding the materials to be bonded together by being cooled and solidified thereafter. In the case of using the adhesive containing the resin composition for dielectric heating adhesion of the present invention, an applicator having a large heating furnace is not required. The bonding process can be simplified. Therefore, productivity can be greatly improved by using an adhesive containing the resin composition for dielectric heating adhesion of the present invention.
[0012]
Here, high-frequency heat generation is considered to be due to heat generation due to molecular friction based on molecular polarization, and generally the heat generation efficiency due to the application of high-frequency voltage of a thermoplastic resin is the dielectric constant (ε), dielectric loss tangent ( tan δ) and the dielectric loss coefficient {(ε) × (tan δ)}, which is the product of these, are considered to be superior. Among thermoplastic resins, polyolefin resins mainly composed of hydrocarbon bonds, such as polyethylene resins and polypropylene resins, are non-polar and therefore have low dielectric constant (ε) and dielectric loss tangent (tan δ) for high-frequency heating. Is considered unsuitable.
[0013]
On the other hand, polyolefin resin is excellent in toughness, impact resistance, flexibility, workability, transparency, acid resistance, alkali resistance, low permeability to water, thermal stability, electrical insulation, etc. Since it exhibits high viscosity, it can be said that it has properties suitable as a binder resin for adhesives. In addition, since the polyolefin-based resin is the most mass-produced resin in the world, it is excellent in that it is easily available and inexpensive. Therefore, there is a strong demand for the development of a technology that makes it possible to use a polyolefin-based resin as a binder resin for a hot-melt adhesive capable of dielectric heating.
[0014]
In fact, in order to overcome the above-mentioned problems while taking advantage of the excellent properties of polyolefin resins, technology that mixes polyolefin resins with highly polar resins such as polyvinyl chloride resin and dielectric loss in thermoplastic resins A technique for blending an inorganic substance having a large coefficient (for example, see Patent Document 1) and a technique for blending a ferroelectric material in a thermoplastic resin (for example, see Patent Document 2) have been proposed. However, due to insufficient heat generation, it takes too much time for heating and is not practical. Polyvinyl chloride resin is harder to handle during construction due to its higher specific gravity than polyolefin resin, and incineration may produce substances that adversely affect the human body and the global environment, including dioxin. There's a problem.
[0015]
In addition, since the amount of heat generated by dielectric heating to which a high frequency voltage is applied is completely insufficient, electromagnetic induction heating using induction heating of a conductor with a high frequency coil by blending a ferromagnetic material is also used (for example, However, since the efficiency of induction heating of such a composite is low, when the heat capacity of the material to be bonded is insufficient compared to the heat capacity of the adhesive, the adhesive is raised to a temperature necessary for bonding. Takes a long time, so the productivity is low, and at present it is not in a stage where it can be put into practical use.
[0016]
Furthermore, a film is disclosed in which an electromagnetic wave absorber such as ferrite is blended or applied to a nonpolar resin film such as a polyolefin resin (see, for example, Patent Document 4). Further, a thermoplastic resin composition in which a high-frequency or microwave sensitizer in which 3 to 30 parts by mass of a liquid polar substance is adsorbed to 2 to 20 parts by mass of an inorganic other porous powder is added to 100 parts by mass of a thermoplastic resin. (For example, refer to Patent Document 5). However, even if these techniques are used, the polyolefin resin can be heated and melted in a sufficiently short time, and it is not yet possible to use it as a resin composition for dielectric heating adhesion having sufficiently strong adhesiveness. .
[0017]
And ultra high molecular weightpolyethyleneIn addition, a technique of adding a radio frequency sensitizer such as zinc oxide, bentonite, and an alkali metal or alkaline earth metal aluminosilicate and a substance suitable for improving radio frequency sensitivity is disclosed (for example, Patent Documents). 6). Moreover, the technique which adds the radio frequency energy sensitizer which consists of a composition which mix | blended 4-10 mass% N-ethyltoluene sulfonamide with the thermoplastic polymer is disclosed (for example, refer patent document 7). Furthermore, the technique of mix | blending 20-200 mass parts inorganic powder which has crystal water with 100 mass parts of polyolefin resin is disclosed (for example, refer patent document 8). Q. X. Nguyen, R.A. Gauvin, Y.M. The technique of adding sodium aluminosilicate to ultra high molecular weight polyethylene, as disclosed in Belanger; ANTEC '91, p2245-2247, is generally well known. As commercially available microwave sensitizers, those manufactured by STRUKTOL (USA), FREQUON (trade name), and the like are well known. However, even if these techniques are used, it is still possible to heat and melt polyolefin resin in a sufficiently short time, and it is still not possible to use it as a resin composition for dielectric heating adhesion having sufficiently strong adhesiveness. It is.
[0018]
Further, it is well known that among polyolefin resins, ethylene copolymers having a polar group such as ethylene-vinyl acetate copolymer and ethylene-methyl acrylate copolymer can be fused at high temperature. And the technique which mixes polyamide, a vinyl polymer, polyester, or polyurethane with a propylene-alpha-olefin block copolymer is disclosed (for example, refer patent document 9).
[0019]
Further, a resin composition is disclosed in which a propylene polymer and an ethylene copolymer composed of ethylene and an unsaturated carboxylic acid and / or an unsaturated carboxylic acid derivative are blended (see, for example, Patent Document 10). . However, at present, these copolymers are insufficient in terms of adhesiveness and time required for heating.
[0020]
Here, as described above, in order to shorten the bonding process time of the material to be bonded, if an adhesion method that performs rapid heating using a hot melt adhesive is selected, not only the hot melt adhesive but also the material to be bonded can be obtained. Since it takes time to re-harden the material to be bonded after being softened or melted, there was a problem in practical use. In particular, when the heat capacity of the adherend is insufficient compared to the heat capacity of the hot melt adhesive, it takes a long time to raise the hot melt adhesive to the temperature required for bonding, so the productivity becomes low and practical. Not right.
[0021]
Therefore, as the heating rate of the hot melt adhesive is accelerated as described above, there has been an increasing demand for the development of a material that can withstand high-speed heating and solidification of the adherend. Therefore, in recent years, although there are still few examples, several companies etc. have started working on the development of such a material to be bonded for hot melt adhesives.
[0022]
For example, a technique for an interior material including a packing resin layer made of polyethylene terephthalate that is attached to a base material such as a door trim with high adhesiveness by a hot melt adhesive is disclosed (for example, Patent Documents). 11). However, this technique is only intended to improve the adhesion with a general hot melt adhesive, and this document does not describe a hot melt adhesive capable of high frequency dielectric heating.
[0023]
Moreover, until now, wastes of various parts assembled using conventionally known adhesives such as those in the automobile industry and the home appliance industry have been discarded after being crushed because it is difficult to peel off the bonded portions. For this reason, in spite of the demand for promotion of recycling in all industries, various materials constituting waste of various parts cannot be separated and reused or recycled.
[0024]
In order to overcome such problems, in some parts, the use of a hot melt adhesive is attempted, and the hot melt adhesive is heated and melted to peel off the material to be bonded. Achieved results. However, in a part assembled using a conventionally known hot melt adhesive, it is necessary to perform high temperature processing on the entire assembled part in a heating furnace, so the cost due to the necessity of a large heating furnace. There is a certain limit to the effect of promoting reuse due to the increase in the quality of materials and the deterioration of the quality of recycled parts due to heating.
[0025]
Also, in order to disassemble a part assembled with a conventionally known hot melt adhesive, a cycle of a heating process and a cooling process is necessary, and it is necessary to heat up to a part other than the bonded part, resulting in poor heating efficiency. It becomes a big obstacle to industrialization. Therefore, a method for disassembling a part assembled with a conventionally known hot melt adhesive has not been put into practical use in earnest.
[0026]
Therefore, in order to overcome such problems, the parts to be bonded are peeled off by induction heating of the parts bonded with a hot melt adhesive containing a thermoplastic resin composition containing a heating element that generates heat by high frequency induction. Dismantling methods have been developed (see, for example, Patent Document 12). However, it is necessary to insert a metal into the thermoplastic resin composition in advance as a heating element, and it cannot be said that the heating efficiency is sufficient.
[0027]
[Patent Document 1]
JP 52-68273 A
[0028]
[Patent Document 2]
JP 54-161645 A
[0029]
[Patent Document 3]
JP 62-132983 A
[0030]
[Patent Document 4]
Japanese Patent Laid-Open No. 6-182876
[0031]
[Patent Document 5]
JP-A-6-228368
[0032]
[Patent Document 6]
Japanese Patent Publication No. 5-42982
[0033]
[Patent Document 7]
JP-A-2-182419
[0034]
[Patent Document 8]
JP-A-2-129243
[0035]
[Patent Document 9]
Japanese Patent Publication No. 8-193150
[0036]
[Patent Document 10]
Japanese Patent Laid-Open No. 10-273568
[0037]
[Patent Document 11]
JP 2001-58382 A
[0038]
[Patent Document 12]
JP 2002-144341 A
[0039]
[Problems to be solved by the invention]
Based on the above situation, the object of the present invention is to provide a resin composition for dielectric heating adhesion that can be heated and melted by applying a high-frequency voltage for a very short time and has excellent adhesive strength even at a relatively high temperature. It is.
[0040]
Another object of the present invention is to provide a hot melt adhesive that can be heated and melted by applying a high-frequency voltage for a very short time and has excellent adhesive strength even at a relatively high temperature.
[0041]
Another object of the present invention is to provide a method for bonding materials to be bonded that can realize excellent bonding strength by applying a high-frequency voltage for a very short time.
[0042]
In addition, another object of the present invention is to provide a hot melt adhesive that is not easily melted or softened by heating of the hot melt adhesive and re-cured in a short time and exhibits excellent adhesiveness. An object of the present invention is to provide an adherend resin composition used as an adherend for a melt adhesive.
[0043]
Further, another object of the present invention is to dismantle in a short time by applying a high-frequency voltage without using a heating furnace, and to dismantle by applying a high-frequency voltage in which the material of the adherend can be reused well. It is possible to provide an adhesive composite.
[0044]
Another problem of the present invention is that the above-mentioned adhesive complex can save energy, time, and labor during disassembly by efficiently heating only the bonded portion of the above-mentioned adhesive complex. Is to provide a method of dismantling.
[0045]
[Means for Solving the Problems]
In order to provide the above-described dielectric heating adhesive resin composition, hot-melt adhesive, and a method for adhering materials to be bonded, the present inventors include a conductive substance in a polyolefin resin and a dielectric resin of the polyolefin resin. The idea of increasing the tangent was obtained, and extensive studies were conducted using various conductive materials. At the end of the study, the volume resistivity is 10^-2It has been found that the dielectric loss tangent of the polyolefin resin can be increased by containing a conductive substance having a resistance of Ω · cm or less, and the dielectric heat-bonding resin composition of the present invention, the hot melt adhesive, and the adhesion between the adherends Completed the method.
[0046]
That is, the dielectric heating adhesive resin composition of the present invention has a polyolefin resin having a melting point in the range of 80 to 200 ° C. and a volume resistivity of 10^-2A conductive material that is Ω · cm or less, the content of the conductive material is in the range of 1 to 30% by volume, and the dielectric loss tangent at 23 ° C. is 0.03 or more at a frequency of 40 MHz. Features.
[0047]
Here, it is more desirable that the content of the conductive material is in the range of 5 to 25% by volume. In addition, the dielectric heat-bonding resin composition of the present invention preferably has a dielectric loss tangent of 0.1 or more at 23 ° C. at a frequency of 40 MHz.
[0048]
In the resin composition for dielectric heating adhesion of the present invention, the volume resistivity of this conductive material is 10^-FourIt is preferable that it is below Ω · cm. Further, the conductive material includes iron, copper, silver, an alloy containing iron as a main component, an alloy containing copper as a main component, an alloy containing silver as a main component, carbon, and an inorganic compound containing carbon as a main component. It is desirable to contain one or more materials selected from
[0049]
The conductive material preferably has one or more shapes selected from the group consisting of powder, granule, granule, needle, fiber, and scale. At this time, it is desirable that the conductive material has an average particle diameter in the range of 10 to 500 μm. Further, it is recommended that the conductive material be contained in a state of being uniformly dispersed in the resin composition for dielectric heating adhesion.
[0050]
In addition, the conductive material may have one or more shapes selected from the group consisting of a net shape, a thin film shape, a string shape, and a rod shape. At this time, the resin composition for dielectric heating adhesion of the present invention may have a structure in which a layer containing this conductive substance and a layer containing a resin composition containing a polyolefin resin are laminated. Here, it is preferable that the resin composition for dielectric heating bonding of the present invention is formed into a thin film.
[0051]
Furthermore, it is preferable that the resin composition for dielectric heat bonding of the present invention is heated and melted by applying a high-frequency voltage, and then solidified by cooling to exhibit adhesiveness. In this case, the resin composition for dielectric heating adhesion of the present invention is applied with a high-frequency voltage in the range of 1 to 5000 MHz and a high-frequency output in the range of 0.1 to 100 kW in the range of 1 to 1000 seconds. It is desirable to melt by heating.
[0052]
Moreover, the hot-melt adhesive of the present invention is characterized by containing the resin composition for dielectric heating adhesion.
[0053]
And the adhesion method of the to-be-adhered material of this invention is a range whose frequency is 1 to 5000 MHz with respect to the said hot-melt-adhesive pinched | interposed between to-be-adhered materials, and the range of 0.1-100 kW high frequency output Including a step of heating and melting by applying the high frequency voltage in the range of 1 to 1000 seconds.
[0054]
In order to solve the above-mentioned problems, the inventors of the present invention provide a resin composition that is difficult to melt or soften by heating because of its high melting point, and that is easily re-cured in a short time because of its high crystallization exothermic peak temperature. The idea that it should be used as an adhesive for hot melt adhesives was obtained, and extensive studies were conducted using various types of resin compositions. And after the examination, the present inventors are a resin composition for adhesion containing a crystalline thermoplastic resin and having a bending strength at 23 ° C. in the range of 100 to 400 MPa, and this crystalline heat The plastic resin has a melting point in the range of 150 to 350 ° C., and the difference between this melting point and the crystallization exothermic peak temperature in the temperature lowering process from the molten state at a temperature lowering rate of 10 ° C./min is 0 to 70 ° C. Adhesives using crystalline thermoplastic resins in the range of 1 are difficult to melt or soften by heating and are easy to re-harden, so they are suitable for use as hot melt adhesives. As a result, the resin composition for adhesion of the present invention was completed.
[0055]
That is, the adherend resin composition of the present invention is an adherend resin composition used as an adherend of a hot melt adhesive, and the adherend resin composition contains a crystalline thermoplastic resin. In addition, the resin composition for adhesion having a bending strength at 23 ° C. in the range of 100 to 400 MPa, and the crystalline thermoplastic resin has a melting point in the range of 150 to 350 ° C. It is a resin composition for adhesion, which is a crystalline thermoplastic resin having a difference from the crystallization exothermic peak temperature in the temperature lowering process from the molten state at a rate of 10 ° C./min in the range of 0 to 70 ° C. .
[0056]
Here, it is preferable that the resin composition for adhesion of the present invention has a dielectric loss tangent in a range of 0 to 0.1 at 23 ° C. at a frequency of 40 MHz.
[0057]
Moreover, it is preferable that this crystalline thermoplastic resin contains a polyester-type resin. Furthermore, it is more desirable that the crystalline thermoplastic resin contains a polyester resin and a polyolefin resin.
[0058]
And it is recommended that the resin composition for adhesion of this invention contains 1 or more types of crystal nucleating agents chosen from the group which consists of a fatty-acid metal salt, a benzoate, a sorbitol type compound, a talc, and a clay. Moreover, it is preferable that the resin composition for adhesion of this invention contains 1 or more types of reinforcing agents chosen from the group which consists of a fibrous reinforcing material, a coupling agent, and a mineral reinforcing material.
[0059]
Moreover, it is desirable for the resin composition for adhesion of the present invention to have an adhesive strength of 1.0 to 10 MPa with a hot melt adhesive that melts by high-frequency dielectric heating. Here, the hot melt adhesive has a polyolefin resin having a melting point in the range of 80 to 200 ° C. and a volume resistivity of 10^-2A hot melt adhesive having a dielectric loss tangent of 0.03 or more at 23 ° C. at a frequency of 40 MHz, and containing the conductive substance in the hot melt adhesive. It is recommended that the amount be in the range of 1-30% by volume.
[0060]
In addition, the present inventors provide a hot melt adhesive that contains a dielectric heating adhesive resin composition and is heated and melted by applying a high-frequency voltage, in order to provide the above-mentioned adhesive composite and the method for disassembling the adhesive composite. The idea is to use an adhesive composite comprising an adhesive and an adherend bonded to the bonded portion by this hot melt adhesive, and an adhesive composed of various types of hot melt adhesives and adherends. The composite body was prototyped and earnestly studied. And after the examination, the present inventors have a polyolefin resin having a melting point in the range of 60 to 200 ° C. and a volume resistivity of 10^-2And a conductive material having a resistance of Ω · cm or less, a dielectric loss tangent at 23 ° C. at a frequency of 40 MHz of 0.03 or more, and a conductive composition of 1 to 30% by volume of the conductive material. Can be disassembled in a short time by applying a high-frequency voltage without using a heating furnace, and the material of the adherend can be reused well, dismantling by applying a high-frequency voltage The present inventors have found that an adhesive complex can be obtained, and completed the adhesive complex and the method for disassembling the adhesive complex of the present invention.
[0061]
That is, the adhesive composite of the present invention is an adhesive composite comprising a hot melt adhesive and an adherend bonded at the joint by the hot melt adhesive. A hot-melt adhesive containing a heat-bonding resin composition and heated and melted by applying a high-frequency voltage. This dielectric heat-bonding resin composition has a melting point in the range of 60 to 200 ° C. And the volume resistivity is 10^-2A dielectric material having a dielectric loss tangent under a condition of 23 ° C. at a frequency of 40 MHz of 0.03 or more, and the dielectric heating adhesion of the conductive material. The content in the resin composition for use is an adhesive composite that can be disassembled by applying a high-frequency voltage in the range of 1 to 30% by volume.
[0062]
Here, it is preferable that the dielectric loss tangent of the dielectric heating adhesive resin composition at 23 ° C. at a frequency of 40 MHz is 0.1 or more.
[0063]
The volume resistivity of this conductive material is 10^-FourIt is desirable that it is below Ω · cm. Further, the conductive material includes iron, copper, silver, an alloy containing iron as a main component, an alloy containing copper as a main component, an alloy containing silver as a main component, carbon, and an inorganic compound containing carbon as a main component. It is recommended to contain one or more materials selected from
[0064]
The conductive material has one or more shapes selected from the group consisting of powder, granules, granules, needles, fibers, scales, and the dielectric heating adhesive resin composition. It is preferable that it is contained in a uniformly dispersed state.
[0065]
Further, it is desirable that the dielectric loss tangent of the adherend at a frequency of 40 MHz under the condition of 23 ° C. is in the range of 0 to 0.1. Furthermore, it is recommended that the dielectric loss tangent of the resin composition for dielectric heating adhesion at a frequency of 40 MHz is larger than twice the dielectric loss tangent of the adherend at a frequency of 40 MHz.
[0066]
The method for disassembling an adhesive composite according to the present invention includes a step of heating and melting the hot melt adhesive by applying the high-frequency voltage to the joint, and peeling the adherend at the joint. A step of disassembling the above-mentioned adhesive complex.
[0067]
Here, in the step of heating and melting, the high frequency voltage having a frequency in the range of 1 to 5000 MHz and a high frequency output of 0.1 to 100 kW is applied to the joint portion in a range of 1 to 1000 seconds. Preferably, the step of applying is included.
[0068]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described in more detail with reference to embodiments.
[0069]
<Resin heating adhesive resin composition>
First, the resin composition for dielectric heating adhesion will be described.
[0070]
Here, in the present specification, the resin composition for dielectric heating adhesion is a hot melt having the property of adhering materials to be bonded by heating and melting by applying a high frequency voltage and then solidifying by cooling. The resin composition which can be used suitably as a binder of an adhesive shall be pointed out.
[0071]
Next, the dielectric loss tangent (tan δ) of the resin composition for dielectric heating adhesion of the present invention will be described.
[0072]
Here, the dielectric loss tangent (tan δ) refers to the loss factor (tan δ) of the complex dielectric constant. Generally, the heat generation efficiency due to the application of the high frequency voltage of the thermoplastic resin is the dielectric constant (ε), the dielectric loss tangent (tan δ) and these It is considered that the larger the dielectric loss coefficient {(ε) × (tan δ)}, which is the product of
[0073]
The dielectric tangent (tan δ) of the resin composition for dielectric heating adhesion of the present invention at 23 ° C. at a frequency of 40 MHz (hereinafter simply referred to as (tan δ) of the resin composition for dielectric heating bonding of the present invention) is It must be 0.03 or more, preferably 0.1 or more. When the dielectric loss tangent (tan δ) of the resin composition for dielectric heating adhesion of the present invention is less than 0.03, there is a problem that heat generation is poor and the hot melt adhesive does not melt or heating for a long time is required. Because.
[0074]
Next, the polyolefin resin (hereinafter simply referred to as the polyolefin resin used in the present invention) used in the dielectric heating adhesive resin composition of the present invention will be described.
[0075]
Here, in general, an olefin means an unsaturated hydrocarbon having one carbon-carbon double bond and high reactivity, with ethylene and propylene being representative examples. In general, a polyolefin-based resin refers to a resin produced by a polymerization reaction of an olefin monomer, with polyethylene and polypropylene being representative examples.
[0076]
The polyolefin resin used in the present invention is not particularly limited as long as required characteristics are satisfied, and conventionally known polyolefin resins and diene resins can be used. Specific examples of the polyolefin resin include a polyethylene resin, a polypropylene resin, a polyethylene copolymer resin, a polypropylene copolymer resin, an ethylene-propylene copolymer resin, and an ethylene-α olefin copolymer resin.
[0077]
Here, as the polyolefin resin used in the present invention, one or two or more of the aforementioned polyolefin resins can be mixed and used at the same time. In addition, there may be a doubt that the diene resin may not be included in the polyolefin resin. However, in the present specification, the term “polyolefin resin” includes a diene resin for convenience of explanation.
[0078]
In addition, the polyolefin resin used in the present invention includes vinyl acetate, methacrylic acid, acrylic acid, methyl methacrylate, ethyl acrylate, butyl acrylate, methacrylate, and the like in a range of 3 to 50 mol% of the entire polyolefin resin. It is preferable to contain as a copolymerization component. When the monomer component content is less than 3 mol%, the adhesion tends to decrease. When the monomer component content exceeds 50 mol%, the heat resistance of the polyolefin resin is lost. It may be broken.
[0079]
And it is preferable that the polyolefin-type resin used for this invention contains the monomer containing a carboxylic anhydride group, an epoxy group, a hydroxyl group, an isocyanate group, a silanol group etc. as a copolymerization component or a graft polymerization component. Among the above-mentioned monomers, unsaturated carboxylic acid and glycidyl methacrylate are particularly preferable as the copolymer component, and maleic anhydride is particularly preferable as the graft polymerization component.
[0080]
When the above-mentioned functional group is introduced into the polyolefin resin used in the present invention, when the material to be bonded of the hot melt adhesive of the present invention is a reinforced thermoplastic resin, the hot melt adhesive of the present invention and the reinforcement Adhesiveness with a thermoplastic resin can be improved.
[0081]
And the melting point of the polyolefin-type resin used for this invention needs to exist in the range of 80-200 degreeC, and if it exists in the range of 90 to 180 degreeC, it is more preferable. When the melting point is less than 80 ° C., there is a problem that the adhesive strength at a high temperature of the adhesive containing the polyolefin resin is insufficient, and when the melting point exceeds 200 ° C., the polyolefin resin is contained. There is a problem that it takes too much time to melt the adhesive.
[0082]
Here, the content of the polyolefin resin in the resin composition for dielectric heating adhesion of the present invention is preferably in the range of 70 to 99% by volume, and more preferably in the range of 75 to 95% by volume. When the content of the polyolefin resin is less than 70% by volume, the flowability at the time of molding tends to decrease or the adhesive strength tends to decrease, and when the content of the polyolefin resin exceeds 99% by volume, the high frequency There is a tendency not to melt by heating.
[0083]
Subsequently, a conductive material (hereinafter simply referred to as a conductive material used in the present invention) used in the resin composition for dielectric heating adhesion of the present invention will be described. Here, in this specification, the conductive substance is a general term for substances having conductivity, and the material thereof is not limited.
[0084]
Here, in general, induction heating generates random eddy current in a conductor to be heated by electromagnetic induction and generates heat by resistance, while dielectric heating applies voltage to a nonconductor to generate internal owing to molecular polarization. Use frictional heat. In general, the above-mentioned degree of internal friction is evaluated in the form of dielectric loss tangent (tan δ).
[0085]
The volume resistivity (ρ) is 10 in the dielectric heating adhesive resin composition of the present invention.^-2When a conductive material having a resistance of Ω · cm or less is blended, the dielectric loss tangent (tan δ) of the resin composition with respect to the application of the high frequency voltage increases to 0.03 or more, and the dielectric loss tangent (tan δ) and dielectric constant (ε) The dielectric loss coefficient {(ε) × (tan δ)} that is the product of
[0086]
Here, the volume resistivity (ρ) is 10^-2A conductive substance having a very small dielectric loss tangent (tan δ) of 0.0001 or less is generally blended with a polyolefin resin having a dielectric loss tangent (tan δ) of 0.01 to 0.03. It can be said that the increase of the dielectric loss tangent (tan δ) to 0.03 or more is a result that has not been predicted from conventional technical common sense.
[0087]
In high-frequency heating, if the dielectric loss coefficient {(ε) × (tan δ)} is large, the heat generation amount is also large, so that the volume resistivity (ρ) is 10^-2In the resin composition for dielectric heating adhesion of the present invention in which the dielectric loss tangent (tan δ) is increased to 0.03 or more by containing a conductive material of Ω · cm or less, the rate of temperature rise with respect to application of a high frequency voltage is increased. Get faster. As a result, the time required for melting the hot melt adhesive of the present invention containing the resin composition is also shortened.
[0088]
Here, the volume resistivity (ρ) of the conductive material used in the present invention is 10^-2Must be Ω · cm or less, 10^-FourIt is preferable if it is Ω · cm or less. The volume resistivity (ρ) of the conductive material is 10^-2If it exceeds Ω · cm, the dielectric loss tangent hardly rises, and there is a problem that heating takes time.
[0089]
The material of the conductive material used in the present invention is not particularly limited, and is conductive and has a volume resistivity (ρ) of 10^-2Any substance that is Ω · cm or less can be used. As a specific example of the material of the conductive material used in the present invention, the volume resistivity (ρ) is 10^-2Iron, copper, silver, an alloy containing iron as a main component (hereinafter simply referred to as an iron-based alloy), an alloy containing copper as a main component (hereinafter simply referred to as a copper-based alloy), Examples thereof include an alloy containing silver as a main component (hereinafter simply referred to as a silver-based alloy), carbon, and an inorganic compound containing carbon as a main component (hereinafter simply referred to as a carbon-based compound).
[0090]
Among the conductive materials described above, iron or iron-based alloys such as α iron, β iron, γ iron, and carbon steel, carbon or carbon-based compounds such as carbon fiber and carbon black, and the like are used for the dielectric heating of the present invention. This is particularly preferable from the viewpoint of the influence on the resin contained in the adhesive resin composition and the economical aspect. Furthermore, the conductive materials described above may be used singly or in combination of two or more.
[0091]
The content of the conductive material used in the present invention relative to the entire resin composition for dielectric heating adhesion of the present invention (hereinafter simply referred to as the content of the conductive material used in the present invention) needs to be in the range of 1 to 30% by volume. If it exists in the range of 5-25 volume%, it is more preferable if it exists in the range of 7-20 volume%.
[0092]
Here, when the content of the conductive material of the present invention is less than 1% by volume, the hot melt adhesive containing the resin composition for dielectric heating bonding of the present invention has insufficient heat generation under high-frequency voltage application conditions and can be bonded. If a long time is required to increase the temperature and the content of the conductive material of the present invention exceeds 30% by volume, the adhesive strength of the hot melt adhesive containing the resin composition for dielectric heating adhesion of the present invention is insufficient. To do.
[0093]
The shape of the conductive material of the present invention is not particularly limited, and may be any shape that can be contained in the resin composition for dielectric heating adhesion of the present invention, and contains the resin composition for dielectric heating adhesion of the present invention. It is selected from shapes suitable for the bonding method applied to hot melt adhesives. Specific examples of the shape of the conductive material of the present invention include powder, granules, granules, needles, fibers, scales, nets, thin films, strings, rods, and the like. Here, the shape of the conductive material of the present invention may be one or two or more of the above shapes at the same time.
[0094]
The above-mentioned shapes such as powder, granule, granule, needle, fiber and scale are used as the shape of the conductive material of the present invention used for kneading into the resin composition for dielectric heating adhesion of the present invention. Often done. At this time, in order to uniformly heat the hot melt adhesive containing the resin composition for dielectric heating adhesion of the present invention by applying a high frequency voltage, the above-mentioned conductive material is uniformly dispersed in the resin composition. It is preferable that it is contained in such a state.
[0095]
When the conductive material of the present invention is one or more selected from the group consisting of powder, granule, granule, needle, fiber, and scale, the average particle size of the conductive material is 1 to 2 It is preferably in the range of 500 μm, and more preferably in the range of 2 to 300 μm. When the average particle size of the conductive material is less than 10 μm, there is a tendency to cause poor dispersion when blended in an adhesive, and when the average particle size of the conductive material exceeds 500 μm, the adhesive strength tends to decrease. There is.
[0096]
It is recommended that the above-mentioned shapes such as a net shape, a thin film shape, a string shape, and a rod shape are used as the shape of the conductive material of the present invention inserted (embedded) in the resin composition for dielectric heating bonding of the present invention. At this time, in order to uniformly heat the hot melt adhesive containing the resin composition for dielectric heating adhesion of the present invention by applying a high frequency voltage, the above-mentioned conductive material is uniformly distributed in the resin composition. It is preferable that it is contained in such a state.
[0097]
In addition, the layer containing the conductive material used in the present invention having the above-described net shape, thin film shape, string shape, rod shape, and the like and the layer containing the polyolefin resin used in the present invention are laminated. Is also recommended. At this time, in order to uniformly heat the hot melt adhesive containing the resin composition for dielectric heating adhesion of the present invention by applying a high frequency voltage, the layer containing the conductive material used in the present invention is a thin sheet. It is desirable that the layer containing the polyolefin-based resin used in the present invention is in contact with an area as wide as possible.
[0098]
In addition, the shape of the resin composition for dielectric heating adhesion of the present invention is not particularly limited, and a suitable shape can be used depending on the application, but in general, the handling is easy, and the production method However, it is preferable to have a thin-film shape in that it can be applied to a variety of shapes of adherends.
[0099]
Furthermore, other components that can be contained in the resin composition for dielectric heating adhesion of the present invention will be described.
[0100]
The dielectric heating adhesive resin composition of the present invention preferably has a silanol group and / or a reactive functional group. Further, the resin composition for dielectric heating adhesion of the present invention is modified with a crosslinking agent having a silanol group and / or a reactive functional group, so that a silanol group and / or a reactive functional group is added to the terminal of the resin contained. More preferably, it has a group. Thus, by having a silanol group and / or a reactive functional group, the adhesiveness between the resin composition for dielectric heating adhesion of the present invention and glass can be improved.
[0101]
Specific examples of the crosslinking agent include γ-aminopropyltriethoxysilane, β- (3,4-epoxycyclohexyl) -ethyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-methacryloxypropyltri. Examples include methoxysilane and N-β- (aminoethyl) -γ-aminopropyltrimethoxysilane.
[0102]
In addition, the resin composition for dielectric heating adhesion of the present invention is various additives such as conventionally known heat stabilizers, weathering agents, hydrolysis resistances, pigments and the like within a range that does not impair the effects of the present invention, depending on applications. May be contained.
[0103]
Specific examples of the heat stabilizer include antioxidants such as hindered phenol antioxidants, thioether antioxidants, phosphite antioxidants, phosphate antioxidants, and combinations thereof. Specific examples of the weathering agent described above include extender pigments such as carbon black, and antioxidants such as benzophenone, triazole antioxidants, and hindered amine antioxidants. Furthermore, specific examples of the aforementioned hydrolysis-resistant agent include carbodiimide compounds, bisoxazoline compounds, epoxy compounds, and isocyanate compounds. As specific examples of the above-mentioned pigments, conventionally known heat-resistant pigments such as polyolefin resins can be suitably used.
[0104]
<Method for producing resin composition for dielectric heating adhesion>
When the conductive material used in the present invention is in the form of powder, granule, granule, needle, fiber, scale, etc., the conductive material used in the present invention and other materials are used in the polyolefin resin used in the present invention. And kneading under the condition of heating until the polyolefin resin melts using an extruder, kneader, roll, etc., and then molding into any shape using a conventionally known resin molding method By this, the resin composition for dielectric heating adhesion of this invention can be obtained.
[0105]
In addition, when the conductive material used in the present invention is in the shape of the net, thin film, string, rod or the like, the conductive material used in the present invention and other components are added to the polyolefin resin used in the present invention. , After melt-kneading under heating conditions using an extruder, kneader, roll, etc., the polyolefin resin containing the conductive material is inserted into a mold of any shape, and a conventionally known injection molding method The resin composition for dielectric heating adhesion of the present invention can also be obtained by molding using.
[0106]
Further, when the conductive material used in the present invention is in the shape of the above-mentioned network, thin film, string, rod or the like, the conductive material used in the present invention and other components are added to the polyolefin resin used in the present invention. After the melt kneading under heating conditions using an extruder, kneader, roll or the like, a layer containing the conductive material and a layer containing the polyolefin resin used in the present invention are formed into a conventionally known resin molding method. The resin composition for dielectric heating adhesion of the present invention can also be obtained by laminating or sandwich-molding using.
[0107]
<Hot melt adhesive>
The hot melt adhesive of the present invention contains the resin composition for dielectric heating adhesion of the present invention. That is, in the hot melt adhesive of the present invention, the dielectric heat bonding resin composition of the present invention exhibits a function as a binder.
[0108]
Here, in this specification, a hot melt adhesive refers to an adhesive that melts by heating and then solidifies by cooling to exhibit adhesiveness.
[0109]
Moreover, the resin composition for dielectric heating adhesion of this invention can also be used as it is as the hot-melt-adhesive of this invention. However, the hot melt adhesive of the present invention may contain other components in addition to the dielectric heating adhesive resin composition of the present invention as long as the effects of the present invention are not impaired depending on the application.
[0110]
Furthermore, the hot melt adhesive of the present invention preferably contains the resin composition for dielectric heating adhesion of the present invention in the range of 30 to 100% by mass, and more preferably in the range of 45 to 100% by mass. When the content of the resin composition for dielectric heating adhesion of the present invention is less than 30% by mass, sufficient heat generation cannot be obtained, and it tends to require a long time for heating.
[0111]
The material to be bonded to which the hot melt adhesive of the present invention is applied is not particularly limited, and any material that can be generally used as a material to be bonded can be suitably used. Specific examples of the adherend to which the hot melt adhesive of the present invention is applied include glass, ceramics, metal, resin, wood, paper, and the like.
[0112]
However, in order to heat and melt the hot melt adhesive of the present invention by applying a high frequency voltage, it is desirable that the adherend does not contain moisture. In addition, when a metal is used as the material to be bonded, it is difficult to heat and melt the hot melt adhesive of the present invention by applying a high frequency voltage when using a material to be bonded containing both sides of the bonding surface. Therefore, it is not preferable.
[0113]
Further, when a resin is used as the adherend, both the thermosetting resin and the thermoplastic resin can be used as the adherend. When the hot melt adhesive of the present invention is used in combination with an appropriate adherend, only the adhesive layer is selectively heated by application of a high frequency voltage, so that a thermoplastic resin having a melting point of 200 ° C. or lower is used. In this case, the present invention can be preferably applied. Depending on the material of the adherend, the polyolefin resin contained in the hot melt adhesive of the present invention reacts with the material of the adherend when heated by applying a high frequency voltage, and the polyolefin resin In some cases, a functional group is introduced into the reaction, but such a reaction is preferable in order to increase the adhesive strength.
[0114]
<Adhesion method of adherend using hot melt adhesive>
The method for adhering the adherend using the hot melt adhesive of the present invention is not particularly limited, and a conventionally known bonding method using a hot melt adhesive can be used. That is, the hot melt adhesive of the present invention is first formed by a method such as extruding into a sheet using a T die, injection molding a plate using a mold, or press forming a sheet. At this time, the temperature of the roll or mold is preferably adjusted to 65 ° C. or lower.
[0115]
However, as a method of bonding the adherend using the hot melt adhesive of the present invention, a high frequency voltage is applied to the hot melt adhesive of the present invention sandwiched between the adherends to heat and melt, and then cooled. Therefore, it is preferable to use an adhesion method including a step of solidifying the hot melt adhesive. By using such an adhesion method, the manufacturing process can be simplified without the need for a heating furnace or the like, and thus productivity can be improved.
[0116]
As a specific example of the method of adhering the adherend using the hot melt adhesive of the present invention, the following series of steps may be mentioned.
[0117]
(I) Glass plate / hot melt adhesive of the present invention / thermoplastic resin molded product, glass plate / hot melt adhesive of the present invention / glass plate, ceramic plate / hot melt adhesive of the present invention / thermoplastic resin molded product A combination of an adhesive / adhesive / adherent material selected from the group consisting of a thermoplastic resin molded article / hot melt adhesive of the present invention / thermoplastic resin molded article, A process of pressing between the upper electrode and the lower electrode.
[0118]
(Ii) A step of applying a high-frequency voltage from the high-frequency oscillator of the high-frequency voltage applying device between the electrodes to cause the hot melt adhesive of the present invention to generate dielectric heat. During the process, when the temperature of the hot melt adhesive rises as time passes and becomes equal to or higher than the melting point of the hot melt adhesive, the hot melt adhesive flows and adheres to the adherend.
[0119]
(Iii) The high-frequency voltage is turned off in a state where the hot melt adhesive and the adherend are bonded, and the composite made of the adherend / adhesive / adherent is cooled by cooling or air blowing.
[0120]
In this way, the composite bonded and bonded under the heating condition above the melting point of the hot melt adhesive of the present invention is used under the temperature condition below the melting point of the hot melt adhesive.
[0121]
Here, in the above-mentioned step (ii), the high-frequency output of the high-frequency voltage is preferably in the range of 0.1 to 100 kW, and more preferably in the range of 0.5 to 20 kW. When the high-frequency output of the high-frequency voltage is less than 0.1 kW, the heating takes time due to insufficient heat generation, so that the adhesive does not melt and cannot be bonded, and when the high-frequency output of the high-frequency voltage exceeds 100 kW, This is because the adhesive tends to generate heat excessively and thermally decompose.
[0122]
In the above-mentioned step (ii), the frequency of the high frequency voltage applied to the adhesive layer is preferably in the range of 1 to 5000 MHz, and more preferably in the range of 5 to 1000 MHz. When the frequency of the high frequency voltage is less than 1 MHz, there is a tendency that the adhesive strength cannot be obtained due to insufficient melting, and when the frequency of the high frequency voltage exceeds 5000 MHz, the adhesive tends to generate excessive heat and thermally decompose. Because.
[0123]
Furthermore, in the above-mentioned step (ii), the application time of the high frequency voltage applied to the adhesive layer is preferably in the range of 1 to 1000 seconds, and more preferably in the range of 10 to 500 seconds. If the application time of the high-frequency voltage is less than 10 seconds, the adhesion state tends to be unstable, and if the application time of the high-frequency voltage exceeds 1000 seconds, the adhesive tends to generate excessive heat and thermally decompose. Because there is.
[0124]
When a high frequency voltage is applied to the hot melt adhesive of the present invention, only the adhesive layer is heated by high frequency dielectric heating, so that it is not necessary to treat the entire material to be bonded in a heating furnace, and a large material to be bonded is bonded. It is especially effective when. In addition, since only the adhesive layer can be selectively heated by applying a high frequency voltage, the hot melt adhesive of the present invention can be used in an assembly process of a product including a part having a low heat resistance as a part of the adherend. Use is effective.
[0125]
Therefore, members using the hot melt adhesive of the present invention as an adhesive include automobiles, electrical equipment, industrial machinery, office equipment, information processing equipment, civil engineering and building materials, paper products, clothing, and chemical products. It is suitably used in the manufacturing process and can contribute to the improvement of the productivity of the product and the reduction of the manufacturing cost.
[0126]
<Adhesive resin composition>
The resin composition for adhesion of the present invention used as a material to be adhered to a hot melt adhesive has a melting point in the range of 150 to 350 ° C., and a molten state under the condition of the melting point and the temperature decreasing rate of 10 ° C./min. The crystalline thermoplastic resin in which the difference from the crystallization exothermic peak temperature in the temperature lowering process from 0 to 70 ° C. is contained, and the bending strength at 23 ° C. needs to be in the range of 100 to 400 MPa.
[0127]
Here, the melting point (Tm) and the crystallization exothermic peak temperature (Tc) are measured using a differential scanning calorimeter. Heating is performed at a rate of temperature increase of 20 ° C./min in a nitrogen atmosphere, and the temperature of the melting endotherm is set to Tm (° C.). Thereafter, the temperature was lowered at a rate of 10 ° C./min, and the crystallization exothermic peak temperature was defined as Tc (° C.). As the difference between Tm and Tc is smaller, crystallization starts even when the degree of supercooling is small, and the crystallization rate is faster.
[0128]
The difference between Tm and Tc is naturally 0 ° C. or more, and when heated to a temperature exceeding Tm, the interface between the hot melt adhesive and the resin composition to be bonded partially melts and solidifies. Adhesive strength is improved. Furthermore, the difference between Tm and Tc needs to be 70 ° C. or less, and preferably 50 ° C. or less. If this difference exceeds 70 ° C., it takes a long time for the molten resin composition to be bonded to recrystallize and solidify. Therefore, it is preferable to use it as a material for the material to be bonded to the hot melt adhesive. Absent.
[0129]
And this Tm needs to be 150 degreeC or more, it is preferable that it is 160 degreeC or more, and if it is 200 degreeC or more especially, it is more preferable. The Tm needs to be 350 ° C. or lower when a heat-resistant crystalline thermoplastic resin is used, and is preferably 270 ° C. or lower when a normal crystalline thermoplastic resin is used. When this Tm is less than 150 ° C., the heat resistance of the adherend resin composition may be insufficient. Moreover, when this Tm exceeds 350 degreeC, it may become difficult to shape | mold with a general purpose molding machine.
[0130]
The dielectric loss tangent of the resin composition for adhesion of the present invention under the condition of 23 ° C. at a frequency of 40 MHz is naturally 0 or more, but preferably 0.1 or less, particularly 0.05 or less. More preferable. Since the resin composition for adhesion having a dielectric loss tangent of 0.1 or less is difficult to be heated even when a high frequency voltage is applied, the temperature difference from the hot melt adhesive of the present invention that is subjected to high frequency dielectric heating can be increased. A wide range of conditions is preferable.
[0131]
<Crystalline thermoplastic resin used for resin composition for adhesion>
Moreover, it is preferable that the resin composition for adhesion of this invention contains a polyester-type resin as a crystalline thermoplastic resin. This is because polyester resins have high strength and rigidity and high dimensional change stability. This is also because the polyester resin has a low water absorption and a low dielectric loss tangent.
[0132]
Furthermore, it is preferable that the resin composition for adhesion of the present invention contains a polyester resin and a polyolefin resin as the crystalline thermoplastic resin. This is because by containing a polyolefin resin in addition to the polyester resin, the adhesiveness to the hot melt adhesive tends to be dramatically improved.
[0133]
In addition, it is preferable that the content rate of the crystalline thermoplastic resin in the resin composition for adhesion of this invention is 60 mass% or more, and it is more preferable if it is especially 65 mass% or more. The content is preferably 99% by mass or less, and more preferably 98% by mass or less. When this content is less than 60% by mass, the strength and rigidity are greatly reduced and tend to be deformed or broken during use, and when this content exceeds 99% by mass, the adhesive strength decreases. This is because there is a tendency.
[0134]
The content of the polyester resin in the crystalline thermoplastic resin of the present invention is preferably 60% by mass or more, and more preferably 70% by mass or more. The content is preferably 99% by mass or less, and more preferably 98% by mass or less. When this content is less than 60% by mass, the strength and rigidity are greatly reduced and tend to be deformed or broken during use, and when this content exceeds 99% by mass, the adhesive strength decreases. This is because there is a tendency.
[0135]
The content of the polyolefin resin in the crystalline thermoplastic resin of the present invention is preferably 1% by mass or more, more preferably 2% by mass or more. The content is preferably 40% by mass or less, and more preferably 30% by mass or less. This is because when the content is less than 1% by mass, the adhesive strength tends to decrease, and when the content exceeds 40% by mass, the rigidity and strength tend to decrease.
[0136]
Here, the crystalline thermoplastic resin used in the present invention is not limited to polyester resins and polyolefin resins, and has a melting point in the range of 150 to 350 ° C. Any crystalline thermoplastic resin having a difference from the crystallization exothermic peak temperature in the temperature lowering process from the molten state under the condition of ° C./min in the range of 0 to 70 ° C. may be used.
[0137]
Specific examples of the crystalline thermoplastic resin used in the present invention include polyalkylene terephthalate resins, polyamide resins, polyacetal resins, polypropylene resins, and polyphenylene sulfide resins. When these resins are used, a resin composition to which a crystal nucleating agent is added is preferable.
[0138]
More preferable specific examples include polybutylene terephthalate resin, polyethylene terephthalate resin, polypropylene terephthalate resin, polybutylene naphthalate resin, polyamide 6 resin, polyamide 66 resin, polyamide MXD6 resin, polyacetal resin, Examples thereof include modified polyacetal resins, polyphenylene sulfide resins, and copolymer resins thereof.
[0139]
Of these, polyacetal resins, polybutylene terephthalate resins, and polyethylene terephthalate resins are particularly preferred because of their low dielectric loss tangent. In particular, polybutylene terephthalate resins and their copolymer resins, polybutylene terephthalate resins and polymer alloys of polyethylene terephthalate resins, etc., have high strength and high crystallization speed, and have a lower dielectric loss tangent than other resins. The temperature rise of the adherend during bonding is suppressed, and it is most preferable because it is easy to handle.
[0140]
In addition, when these resins are used, the object of the present invention can be sufficiently achieved even if a bottle recovery product is used, which is preferable from the viewpoint of social demands for promoting a recycling society. The shape of the resin used in the present invention may be virgin flakes or pellets, but may be flakes obtained by pulverizing bottle collection products, or flakes melted in an extruder and pelletized. The shape is not limited.
[0141]
Here, among the copolymer components of the polyester-based resin contained in the crystalline thermoplastic resin used in the present invention, the glycol component is not particularly limited. For example, ethylene glycol, 1,3- Examples include propylene glycol, butanediol, neopentyl glycol, cyclohexane dimethanol, diethylene glycol, polyethylene glycol, polytetramethylene glycol, and polylactone.
[0142]
Moreover, it is preferable to use a terephthalic acid as a main component as an acid component among the copolymerization components of the polyester-type resin contained in the crystalline thermoplastic resin used for this invention. However, known acid components other than terephthalic acid, for example, naphthalenedicarboxylic acid, isophthalic acid, adipic acid, sebacic acid and the like can be suitably used in addition to terephthalic acid. In addition, when these publicly known acid components other than terephthalic acid exceed 20 mol%, the crystallinity of the crystalline thermoplastic resin used in the present invention is reduced, and moldability and rigidity are lowered, which is not preferable.
[0143]
Furthermore, as a polyester resin contained in the crystalline thermoplastic resin used in the present invention, a polyester resin having a high terminal acid value, a polyester resin in which an acid component having a polar group or a glycol component is copolymerized Are also preferably used.
[0144]
In addition, in order to make the dielectric loss tangent of the resin composition for adhesion of the present invention under the condition of 23 ° C. at a frequency of 40 MHz in the range of 0 to 0.1, it is contained in the crystalline thermoplastic resin used in the present invention. It is preferable that the dielectric loss tangent of the polyester-based resin is 0.2 or less. In this case, since the polyester-based resin contained in the crystalline thermoplastic resin used in the present invention is not easily heated even when a high-frequency voltage is applied, the hot-melt adhesive of the present invention that is subjected to high-frequency dielectric heating The temperature difference between the two can be increased.
[0145]
<Bending strength of resin composition for adhesion>
The bending strength at 23 ° C. of the adherend resin composition of the present invention needs to be 100 MPa or more, and preferably 150 MPa or more. The bending strength is generally 300 MPa or less. When the bending strength is 100 MPa or less, the adherend made of the adherend resin composition is deformed by the load or heat during bonding, and the object of the present invention is not achieved.
[0146]
Therefore, the resin composition for adhesion of the present invention preferably contains a fibrous reinforcing material and / or a mineral reinforcing material in order to improve the bending strength and impact resistance of the bonded material. It is even more preferable if a coupling agent is further contained in addition to the material and / or the mineral reinforcing material.
[0147]
The fibrous reinforcing material is not particularly limited. For example, glass fibers, carbon fibers, acicular wollastonite, and inorganic fibers including whiskers such as calcium titanate and aluminum borate, Examples include heat-resistant organic fibers such as aramid fibers and polyphenylene sulfide fibers. Of these fibrous reinforcing materials, glass fibers, acicular wollastonite, aramid fibers, and the like are particularly preferable. Further, the fiber diameter of these fibrous reinforcing materials is preferably 1 to 30 microns, and more preferably 6 to 20 microns.
[0148]
Furthermore, the mineral reinforcing material is not particularly limited, and examples thereof include talc, clay, wollastonite, silica, calcium carbonate and mica.
[0149]
In addition, the coupling agent is not particularly limited. For example, an epoxy coupling agent, an acrylic coupling agent, a urethane coupling agent, a silane coupling agent, a titanate coupling agent, and the like. Is mentioned. In particular, when the hot melt adhesive contains a polyester resin, the resin composition for adhesion of the present invention includes an epoxy coupling agent and an acrylic coupling for improving adhesion with the polyester resin. Containing polyester agent, urethane coupling agent, silane coupling agent, and chemically bonded polyester resin and fibrous reinforcement and / or mineral reinforcement by being treated with these coupling agents Is preferably formed.
[0150]
The amount of these reinforcing materials is preferably 5 parts by mass or more, particularly 10 parts by mass or more with respect to 100 parts by mass of the crystalline thermoplastic resin used in the resin composition for adhesion of the present invention. More preferable. Moreover, it is preferable that this compounding quantity is 150 mass parts or less, and it is more preferable if it is especially 100 mass parts or less. When the blending amount is less than 5 parts by mass, the effect of improving the strength tends to be small. When the blending amount exceeds 150 parts by mass, the resin fraction in the resin composition to be bonded is reduced and hot melt is reduced. There exists a tendency for adhesiveness with an adhesive agent to fall.
[0151]
<Crystal nucleating agent>
The adherend resin composition of the present invention preferably contains a crystal nucleating agent. By containing the crystal nucleating agent, the difference between Tm and Tc of the crystalline thermoplastic resin contained in the resin composition for adhesion of the present invention can be reduced, so that the crystallization speed can be increased. Because. The crystal nucleating agent that can be suitably used in the present invention is not particularly limited, and examples thereof include fatty acid metal salts, benzoates, sorbitol-based crystal nucleating agents, talc, and clay.
[0152]
The content of the crystal nucleating agent contained in the adhesive resin composition of the present invention with respect to 100 parts by mass of the entire adhesive resin composition is preferably 0.1 parts by mass or more, particularly 0.5 mass. It is more preferable if it is at least part. The content is preferably 50 parts by mass or less, and more preferably 40 parts by mass or less. When the content is less than 0.1 parts by mass, the crystallization promoting effect by the crystal nucleating agent tends to be small, and when the content exceeds 50 parts by mass, the resin composition for adhesion is used as a material. There exists a tendency for the intensity | strength and adhesive strength of a to-be-adhered material to fall.
[0153]
Further, a hot melt adhesive that can be suitably used for bonding an adherend made of the resin composition for adhesion of the present invention is a hot melt adhesive that melts by high-frequency dielectric heating. The adhesive strength between the agent and the resin composition for adhesion of the present invention is preferably 1.0 or more, and usually 10 MPa or less under general conditions. When this adhesive strength is less than 1.0 MPa, there is a tendency to cause adhesion peeling during use.
[0154]
<Hot-melt adhesive for resin composition for adhesion>
The hot melt adhesive that can be suitably used for bonding an adherend made of the adhesive resin composition of the present invention is not particularly limited, and conventionally known hot melt adhesives can be used. The above-described hot melt adhesive of the present invention is preferably used because it can be heated and melted by applying a high-frequency voltage for a very short time and has excellent adhesive strength even at a relatively high temperature.
[0155]
In addition, among the hot melt adhesives of the present invention described above, the use of a hot melt adhesive containing a polyolefin resin having a melting point in a specific range may cause deformation or heating of the adhesive resin composition of the present invention. This is preferable in order to achieve excellent adhesive strength without modification. Here, the melting point in the specific range is preferably 80 ° C. or higher, and more preferably 90 ° C. or higher. Moreover, it is preferable that melting | fusing point of this specific range is 150 degrees C or less, and if it is especially 145 degrees C or less, it is more preferable.
[0156]
Although it does not specifically limit as resin contained in the hot-melt-adhesive which can be used suitably for adhesion | attachment of the to-be-adhered material which uses the resin composition for to-be-adhered of this invention as a material, Polyolefin-type resin, polyamide-type resin, polyester Based resins and the like. Among these hot melt adhesives, the polyolefin resin, which includes a polar group and a reactive functional group, is used for adhesion of an adhesive material made of the resin composition for adhesion of the present invention. A hot melt adhesive containing a resin polymer alloy product is particularly preferred.
[0157]
<Adhesive material made of the resin composition for adhesion>
Moreover, the adherend which uses the resin composition for adherend of this invention as a material is used suitably for adhesion | attachment of a dissimilar material. Although it does not specifically limit as a counterpart material, For example, glass, a metal, wood, a thermosetting resin molded product, etc. are mentioned. Among these, glass, metal, wood and the like are particularly preferably used as the counterpart material.
[0158]
As a welding method by heating a conventionally known hot-melt adhesive or the hot-melt adhesive of the present invention, which can be suitably used for bonding an adherend made of the resin composition for bonding of the present invention, spin welding is used. When using frictional heating such as vibration welding or ultrasonic welding, or when using high-frequency heating such as dielectric heating or induction heating, the material to be bonded is also partially heated. It is required to perform in a short time. Therefore, when using such a welding method, it is particularly effective to use an adherend made of the adherend resin composition of the present invention.
[0159]
Furthermore, you may add a conventionally well-known additive to the resin composition for adhesion of this invention in the range which does not impair the characteristic of this invention as needed. Such an additive is not particularly limited, and examples thereof include a heat resistance stabilizer, an antifungal agent, a hydrolysis resistance, and a pigment. Examples of the heat-resistant stabilizer include hindered phenol stabilizers, thioether stabilizers, phosphite stabilizers, and combinations thereof. Examples of the anti-glare agent include carbon black, benzophenone weathering agent, triazole weathering agent, hindered amine weathering agent, and the like. In addition, examples of the hydrolysis resistance include carbodiimide, bisoxazoline, epoxy, and isocyanate compounds. Moreover, as said pigment, the heat-resistant pigment normally used in an engineering plastics type polymer etc. can be used conveniently, for example.
[0160]
And the resin composition for adhesion of this invention can be manufactured by knead | mixing said each component using apparatuses, such as a single screw extruder, a twin screw extruder, and a kneader. There are no particular restrictions on the type of kneading machine and the kneading conditions used here.
[0161]
In addition, the method of molding the adherend resin composition of the present invention obtained by the above-described production method into an adherend is not particularly limited, but is generally injection molding. The mold temperature in the case of injection molding is preferably in the range of 30 to 150 ° C. The shape of the adherend is not particularly limited.
[0162]
<Adhesive complex>
When an adhesive composite comprising a hot melt adhesive and an adherend is manufactured using the hot melt adhesive of the present invention described above, the adhesive composite can be easily decomposed by applying a high frequency voltage. It becomes an adhesive composite that can be used. This is because the hot melt adhesive of the present invention has a property that can be heated and melted by applying a high-frequency voltage for a very short time.
[0163]
That is, the adhesive composite of the present invention comprises the hot melt adhesive of the present invention and an adherend bonded to the bonded portion by the hot melt adhesive, and the hot melt adhesive is a dielectric heating adhesive resin. A hot-melt adhesive containing a composition and heated and melted by applying a high-frequency voltage. The resin composition for dielectric heat-bonding comprises a polyolefin resin having a melting point in the range of 60 to 200 ° C., and volume resistance. Rate is 10^-2A dielectric heat tangent resin composition having a dielectric loss tangent at 23 ° C. at a frequency of 40 MHz of 0.03 or more, and the dielectric heat bond of the conductive material. Since the content in the resin composition for use is in the range of 1 to 30% by volume, it can be disassembled by applying a high-frequency voltage.
[0164]
In the adhesive composite of the present invention, when there are a plurality of the above-mentioned adherends, at least one of them is preferably an adherend made of the adherend resin composition of the present invention. . This is because the adherend made of the resin composition for adherence of the present invention is difficult to melt or soften by heating of the hot melt adhesive and re-cures in a short time when bonded by the hot melt adhesive. This is because the adhesive composite can be easily disassembled and the decomposed material to be reused can be easily reused.
[0165]
<Disassembly method of the adhesive complex>
In the method for disassembling an adhesive composite of the present invention, as shown in FIG. 1, the hot melt adhesive is heated and melted by applying the high-frequency voltage to the joint portion of the adhesive composite (S101). And a step (S102) of peeling off the adherend at the joint.
[0166]
In addition, in the step of heating and melting (S101), the high frequency voltage having a frequency in the range of 1 to 5000 MHz and a high frequency output of 0.1 to 100 kW is applied to the joint portion for 1 to 1000 seconds. The step of applying in a range (S103) is included.
[0167]
Here, when the adhesive composite of the present invention is disassembled using the method of disassembling the adhesive composite of the present invention, the heating method is local heating, so a large heating furnace is not required, and the mechanical force is low. Therefore, even if the material to be bonded is easily damaged or has a large shape, the possibility of damage is reduced. Therefore, by using both the adhesive complex of the present invention and the method of disassembling the adhesive complex of the present invention, the cost for the method of disassembling the adhesive complex can be reduced, and workability and the recycling rate can be improved.
[0168]
The method for disassembling an adhesive composite according to the present invention is particularly effective when there are a plurality of materials to be bonded and at least one of them is a material to be bonded made of glass or ceramic. In this case, the resin contained in the resin composition for dielectric heating adhesion of the present invention, which is a component constituting the hot melt adhesive of the present invention provided in the adhesive composite of the present invention, has a silane group, a titanate group, etc. By being introduced, the adhesiveness between the adherend made of glass and the hot melt adhesive of the present invention is further improved, and it is preferable because the adhesive composite of the present invention is not degraded.
[0169]
Examples of the monomer containing the silane group, titanate group, and the like include silane compounds and titanate compounds. Specific examples include γ-aminopropyltriethoxysilane, β- (3,4-epoxycyclohexyl). ) -Ethyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-methacryloxypropyltrimethoxysilane, N-β- (aminoethyl) -γ-aminopropyltrimethoxysilane, acylate titanate, phosphate titanate And alcoholate titanates.
[0170]
Here, the method for disassembling the adhesive composite of the present invention is not particularly limited, but for example, it is suitably used for disassembling the adhesive composite of the present invention having the following structure. Specifically, the present invention is obtained by bonding any one or more combinations selected from the group consisting of a glass plate, a ceramic plate, a resin composition molded article, a metal plate, and a wooden plate with the hot melt adhesive of the present invention. It can be used to dismantle the adhesive complex.
[0171]
To further illustrate, glass plate / hot melt adhesive of the present invention / glass plate, glass plate / hot melt adhesive of the present invention / resin composition molded article, glass plate / hot melt adhesive of the present invention / metal plate, heat Plastic resin composition molded article / hot melt adhesive of the present invention / resin composition molded article, metal plate / hot melt adhesive of the present invention / metal plate, metal plate / hot melt adhesive of the present invention / resin composition molded It is used for disassembling the adhesive composite of the present invention comprising a combination of products.
[0172]
The specific method for disassembling the adhesive composite of the present invention is not particularly limited. For example, first, the joint portion of the adhesive composite of the present invention is placed between the electrodes, By applying a high-frequency AC electric field, the heating element (conductive substance) in the hot melt adhesive of the present invention is dielectrically heated. Then, with the passage of time, the temperature of the hot melt adhesive of the present invention rises, and when the temperature exceeds the melting point, the hot melt adhesive of the present invention flows and the materials to be bonded are separated. Then, by turning off the alternating current in the peeled state in this way, or by taking out the material to be peeled off from the adhesive composite of the present invention out of the electric field, moving and cooling, or cooling with air or the like, The adhesive composite of the present invention can be disassembled. The method for disassembling the adhesive composite of the present invention melts the hot melt adhesive of the present invention at a temperature not lower than the melting point of the hot melt adhesive of the present invention and not higher than the melting point or decomposition temperature of the adherend. Is preferably performed.
[0173]
Here, when the method for disassembling the adhesive composite of the present invention is used, only the joint portion of the adhesive composite of the present invention is heated by high-frequency dielectric heating. Therefore, it is not necessary to treat the entire bonded composite of the present invention in a heating furnace, and it is possible to reduce energy consumed during disassembly.
[0174]
When the method for disassembling the adhesive composite of the present invention is used, only the joint portion of the adhesive composite of the present invention can be selectively heated. Therefore, when the adhesive composite of the present invention has a large shape, or when the adhesive composite of the present invention includes a part of the adherend that includes a portion having low heat resistance, the disassembly method of the adhesive composite of the present invention is It is particularly effective. In addition, the method for disassembling an adhesive composite according to the present invention is a member assembled by adhering a material to be bonded with the hot melt adhesive according to the present invention, and thus was used for automobiles, electricity, OA equipment, building materials, and the like. Even when recovered later, it can be easily disassembled and reused while minimizing deformation and modification of the adherend.
[0175]
【Example】
<Resin Heat Adhesive Resin Composition, Hot Melt Adhesive, Adhesive Method for Adhering Material>
EXAMPLES Hereinafter, examples will be given to describe the method for bonding a dielectric heating adhesive resin composition, a hot melt adhesive, and an adherend of the present invention in more detail, but the present invention is not limited to these.
[0176]
<Example 1>
First, the polyolefin resin and conductive powder shown in Table 1 were premixed at the blending ratio shown in Table 1. Next, the preliminary mixture was supplied to the hopper of a twin-screw extruder PCM30φ (manufactured by Ikekai Tekko Co., Ltd.) whose temperature was adjusted to 170-180-180 ° C. from the hopper side, and melt mixed at a screw rotation speed of 60 rpm. And after cooling the strand extruded from the twin-screw extruder in the water bath, it cut | disconnected and obtained the pellet of the hot-melt-adhesive containing a conductive substance.
[0177]
<Examples 2 to 12>
First, the polyolefin resin and conductive powder shown in Table 1 were premixed at the mixing ratios shown in Table 1, respectively. Next, in the same manner as in Example 1, hot melt adhesive pellets were obtained from the preliminary mixture.
[0178]
<Comparative Examples 1-4>
First, the polyolefin resin and conductive powder shown in Table 2 were premixed in the mixing ratios shown in Table 2, respectively. Next, in the same manner as in Example 1, hot melt adhesive pellets were obtained from the preliminary mixture.
[0179]
[Table 1]

[0180]
[Table 2]

[0181]
Here, in Table 1 and Table 2,
* 1: PO-1 represents silane-modified G197 (polyolefin resin made of polyethylene copolymer blend, manufactured by Kureha Elastomer Co., Ltd., melting point 105 ° C.).
* 2: PO-2 represents silane-modified G1019 (polyolefin resin made of polyethylene copolymer blend, manufactured by Kureha Elastomer Co., Ltd., melting point 120 ° C.).
* 3: Fe100 is ASC100 (iron powder, manufactured by Höganäs, average particle size 100 μm, volume resistivity (ρ) 1.4 × 10^-FiveΩ · cm).
* 4: Fe200 is KIP300 (iron powder, manufactured by Kawasaki Steel Corporation, average particle size 200 μm, volume resistivity (ρ) 1.6 × 10^-6Ω · cm).
* 5: Cu100 is CE-6 (copper powder, manufactured by Fukuda Metal Foil Powder Industry Co., Ltd., average particle size 100 μm, volume resistivity (ρ) 1.7 × 10^-6Ω · cm).
* 6: CF is HTA (carbon fiber, manufactured by Toho Rayon Co., Ltd., average length 3 mm, volume resistivity (ρ) 1.5 × 10^-3Ω · cm).
* 7: PO-3 represents EVAFLEX EEA A709 (polyolefin resin made of ethylene ethyl acrylate resin, manufactured by Mitsui DuPont Polychemical Co., Ltd., melting point 56 ° C.).
* 8: PO-4 represents TPX (polyolefin resin composed of polymethylpentene, manufactured by Mitsui Petrochemical Co., Ltd., melting point 265 ° C.).
* 9: SGF05 is a volume resistivity of 10 manufactured by Nitto Boseki Co., Ltd.¹²Represents Ω · cm milled fiber.
[0182]
<Preparation of samples for analysis and evaluation>
First, using the hot melt adhesive pellets obtained in Examples 1 to 12 and Comparative Examples 1 to 4, adhesive plates were prepared using the following molding methods, and required for characteristic analysis and performance evaluation. The to-be-adhered material plate used was produced using the following molding method.
[0183]
(I) Molding of adhesive plate
The hot melt adhesive pellets obtained in Examples 1 to 12 and Comparative Examples 1 to 4 were charged into an injection molding machine in which the temperature of the barrel was adjusted from 180 to 200 to 200 ° C. from the hopper side, and the temperature was increased to 40 ° C. Injection into the adjusted test piece molds yielded adhesive plates of two sizes of 100 × 100 × 1 mm and 100 × 100 × 3 mm, respectively.
[0184]
(Ii) Molding of adherend plate
Injection molding machine in which pellets of 30% by mass glass fiber reinforced modified polybutylene terephthalate (EMC430, manufactured by Toyobo Co., Ltd.) dried at 140 ° C. for 3 hours are temperature-controlled from 250 to 260 to 260 ° C. from the hopper side. The tensile test piece of TYPE I (dumbbell type with a thickness of 3.2 mm) described in ASTM D638 was molded.
[0185]
<Characteristic analysis and performance evaluation>
Next, the adhesive plates composed of the hot melt adhesives of Examples 1 to 12 and Comparative Examples 1 to 4 obtained as described above, the above-mentioned adhesive material plates, and other various adherends shown in Table 3 Using the material plate, the performance evaluation of the hot melt adhesives obtained in Examples 1 to 12 and Comparative Examples 1 to 4 was performed according to the following analysis method and evaluation method. The results are shown in Tables 1 to 3.
[0186]
(I) Measurement of dielectric loss tangent and dielectric loss factor
First, among the adhesive plates made of the hot melt adhesives of Examples 1 to 12 and Comparative Examples 1 to 4, a test piece having a size of 8 × 8 × 3 mm was cut out from an adhesive plate having a size of 100 × 100 × 3 mm. It was. Next, the terminal area Ds connected to the high frequency dielectric heating device (made by Pearl Industry Co., Ltd., impedance analyzer) is 5 cm.²The test piece was sandwiched and fixed between the conductor terminals. Then, a high frequency charge Q having a frequency of 40 MHz was applied to the test piece under the condition of 23 ° C., the potential difference V between the terminals was measured, and the capacitance Cs and the dielectric loss tangent (tan δ) were measured from the potential difference V between the terminals.
[0187]
In addition, dielectric constant ε in vacuum₀8.85 × 10^-14The dielectric loss coefficient ε · tan δ was determined from the following formula (I) as F / cm.
ε · tan δ = Cs × Ds / (ε₀× S) (I)
(Ii) Adhesive strength
The adherend material plate made of the glass fiber reinforced polybutylene terephthalate resin molded article (EMC430, manufactured by Toyobo Co., Ltd.) obtained as described above was cut at the center in the length direction, and 12.7 × 25 A 4 × 3.2 mm adherend plate piece was obtained.
[0188]
Next, among the adhesive plates made of the hot melt adhesives of Examples 1 to 12 and Comparative Examples 1 to 4, from the adhesive plate having a size of 100 × 100 × 1 mm, the size of 12.7 × 25.4 × 3 mm was used. The test piece was cut out and superimposed on the straight portion of the adherend plate piece.
[0189]
Then, as shown in FIG. 2, the obtained adhesive plates 3a, 3b-adhered material plates 5a, 5b are overlapped, and linearly formed on both ends of a 33 × 100 × 3 mm glass plate 1 with a shaft Were fixed together to obtain the composite 100 for evaluating adhesive strength.
[0190]
Subsequently, the terminal area Ds connected to the high frequency dielectric heating device (trade name Impedance Analyzer, manufactured by Pearl Industry Co., Ltd.) is 5 cm.²The adhesive strength evaluation composite 100 was sandwiched and fixed between the conductor terminals. Then, the composite for evaluating the adhesive strength is 2 kg with a 20 mmφ air cylinder./ Cm ² In a pressed state, a high frequency voltage of 40 MHz is applied to the composite for evaluating adhesive strength for 1 minute, 5 minutes, or 20 minutes selected as Tables 1 to 3 as the oscillation time, and the composite for evaluating adhesive strength is applied. After heating the body, it was cooled by air blow for 1 minute to obtain a test piece for evaluating adhesive strength.
[0191]
The test piece for adhesive strength evaluation thus obtained was left in a test room adjusted to 23 ° C. and 50% RH for 5 hours or more. And as shown in FIG. 2, the universal tensile testing machine UTMI type (equipped with a thermostat adjusted to 50 ° C. (Orientec Co., Ltd.The composite 100 for evaluating the adhesive strength is fixed to the chuck of the product manufactured in the state where the tensile shear deformation axis is vertical, and is tensile-sheared in the tensile directions 7a and 7b at a deformation speed of 5 mm / min. The adhesive strength at 50 ° C. of the test piece for strength evaluation was measured.
[0192]
From the results shown in Tables 1 and 2, the hot melt adhesives of Examples 1 to 12 have a polyolefin resin having a melting point of 80 to 200 ° C. and a volume resistivity of 10^-2Ω · cm or less of the conductive material, and since the content of the conductive material with respect to the entire resin composition is in the range of 1 to 30% by volume, the dielectric loss tangent is 0.03 or more. Results It can be seen that the adhesive strength at a relatively high temperature of 50 ° C. is also superior to the hot melt adhesives of Comparative Examples 1 to 4.
[0193]
<Examples 13 to 18>
In order to investigate the adhesive strength of the hot melt adhesive of the present invention with other adherends, the adhesive plates obtained from the hot melt adhesive of Example 3 were used as the various adherends shown in Table 3. It is inserted between the upper surface side and the lower surface side of the plate, and the hot-melt adhesive of Example 3 and other coatings are measured in the same manner as (ii) the method for measuring the adhesive strength in the above-mentioned characteristics analysis and performance evaluation items. The adhesive strength with the adhesive was measured. The results are shown in Table 3.
[0194]
[Table 3]

[0195]
Here, in Table 3, the ceramic plate is a ceramic plate for an electromagnetic cooker manufactured by Toshiba Ceramics Co., Ltd., the aluminum plate is an aluminum plate for a sash manufactured by Furukawa Aluminum Co., Ltd., and the polyamide resin plate is a Toyobo Nylon T manufactured by Toyobo Co., Ltd. A plate made of -402 (glass fiber reinforced polyamide resin) and a PPS plate represent a plate made of Toyobo PPSTS401 (glass fiber reinforced polyphenylene sulfide resin) manufactured by Toyobo Co., Ltd. The size is 12 × 150 × 5 mm.
[0196]
From the results shown in Table 3, it can be seen that the hot melt adhesive of Example 3 has excellent adhesive strength not only for glass and glass fiber reinforced polybutylene terephthalate resin, but also for a wide range of materials to be bonded.
[0197]
<Adhesive resin composition>
Hereinafter, although another Example is given and the resin composition for adhesion of this invention is demonstrated in detail, this invention is not limited to these.
[0198]
<Examples 21-34, Comparative Examples 21-30>
First, based on the combinations of resins, modifiers, and inorganic fillers shown in Tables 4 and 5, their predetermined amounts (Parts by mass) Was weighed and premixed. The preliminary mixture was put into a hopper of a twin screw extruder having a diameter of 30 mm and adjusted to a cylinder temperature of Tm + 30 ° C., and melt-kneaded at a screw rotation speed of 100 rpm to obtain pellets. Among the obtained pellets, a pellet containing a polyester resin and / or a polyphenylene sulfide resin is 140 ° C. for 3 hours, a pellet containing a polyamide resin is 120 ° C. for 2 hours, a polyacetal resin and / or The pellet containing the polyolefin resin was dried at 80 ° C. for 1 hour to obtain a sample for evaluation.
[0199]
And the performance of the sample for evaluation obtained by the following characteristic analysis and the method of performance evaluation was evaluated. The results are also shown in Table 4 and Table 5.
[0200]
[Table 4]

[0201]
[Table 5]

[0202]
Abbreviations in Table 4 and Table 5 are as follows.
PBT: Polybutylene terephthalate (Toyobo Co., Ltd., Viropet EMC700, dielectric loss tangent at 1 MHz: 0.04, dielectric loss tangent at 40 MHz: 0.03)
PET: Polyethylene terephthalate (Toyobo Co., Ltd., Viropet EMC500-01, dielectric loss tangent at 1 MHz: 0.03, dielectric loss tangent at 40 MHz: 0.03)
POM: Polyoxymethylene (manufactured by Polyplastics Co., Ltd., Duracon M90S, dielectric loss tangent at 1 MHz: 0.006, dielectric loss tangent at 40 MHz: 0.005)
PA6: Polyamide 6 (Toyobo Co., Ltd., Toyobo Nylon T800, dielectric loss tangent at 1 MHz: 0.09, dielectric loss tangent at 40 MHz: 0.08)
PP: Polypropylene (manufactured by Grand Polymer Co., Ltd., E7000, dielectric loss tangent at 1 MHz: 0.002, dielectric loss tangent at 40 MHz: 0.003)
RA: Epoxy-modified polyethylene (Nippon Polyolefin Co., Ltd., Lexpearl RA3150)
MP: maleic anhydride modified polypropylene (MMP006, manufactured by Grand Polymer Co., Ltd.)
Glass fiber: Asahi Fiber Glass Co., Ltd., 03JA429
Whisker: Potassium 6 titanate (manufactured by Otsuka Chemical Co., Ltd., Teismo D)
MW: Talc (Hayashi Kasei Co., Ltd., # 5000A)
IO: ionomer resin (Mitsui, Deyupon Polychemical Co., Ltd., High Milan 1707)
MD: Alkyl dibenzylidene sorbitol (Shin Nippon Rika Co., Ltd., Gelol MD)
<Characteristic analysis and performance evaluation>
Next, using the pellets of the resin compositions for adhesion of Examples 21 to 34 and Comparative Examples 21 to 30 obtained as described above, Examples 21 to 34 were performed according to the following analysis method and evaluation method. And the performance evaluation of the pellet of the to-be-adhered resin composition obtained in Comparative Examples 21-30 was performed. The results are shown in Tables 4 and 5.
[0203]
(I) Melting point and crystallization temperature
First, a 10 mg sample is cut and collected from the pellet of the resin composition for adhesion and enclosed in an aluminum pan. Next, the cut and collected sample is set in a DSC (differential scanning calorimeter) sample container. And nitrogen gas 60cm^ThreeThe difference in the amount of heat required to raise the temperature at a rate of temperature increase of 20 ° C./min was automatically recorded while flowing / min. Based on the records obtained, the endothermic peak temperature was determined as the melting point (Tm). Then, it heated up to 30 degreeC temperature higher than Tm, and hold | maintained for 5 minutes. Subsequently, the temperature was decreased at a rate of temperature decrease of 10 ° C./min, the difference in calorie from the standard side was automatically recorded, and the exothermic peak temperature was defined as the crystallization exothermic peak temperature (Tc).
[0204]
(Ii) Bending strength
After melting the pellets of the resin composition for adhesion using an injection molding machine set so that the molten resin temperature becomes Tm + 20 ° C., a thickness of 6 is used using a mold whose surface temperature is adjusted to 50 ° C. A strip of 0.4 mm × width 12.7 mm × length 127 mm was injection-molded with an edge gate at an injection time of 15 seconds and cooling of 15 seconds, and then heat-treated at 140 ° C. for 1 hour to obtain a bending test piece.
[0205]
This specimen was stored in a test room at 23 ° C. and 50% RH for 20 hours, and then subjected to a bending test according to ASTM D790 using a universal tensile testing machine set to a span length of 100 mm and a crosshead speed of 3 mm / min. Obtained by calculation.
[0206]
(Iii) Adhesive strength
After melting pellets of the resin composition to be bonded by an injection molding machine set so that the molten resin temperature becomes Tm + 20 ° C., a test piece mold whose surface temperature was adjusted to 50 ° C. was used to make ASTM A D638-defined TYPE 1 molded product was injection molded at an injection time of 15 seconds and cooled for 15 seconds, and then heat treated at 140 ° C. for 1 hour to obtain an adherend plate. This adherend plate was cut at the center in the length direction.
[0207]
Then, as shown in FIG. 2, 12.7 mm × 25 mm from the hot melt adhesive plate of 100 mm × 100 mm × 1 mm is applied to the straight portion 12.7 mm × 25.4 mm of the cut material plates 5a and 5b. The 4 mm adhesive plates 3a and 3b were cut and overlapped. This lap portion was set linearly on both ends of a glass plate 1 of 33 mm × 100 mm × 3 mm.
[0208]
And the test which changed the cooling time in the range of 0 to 3 minutes after heating this for 1 minute with the high frequency dielectric heating device (made by Pearl Industry Co., Ltd.) in the state pressurized 0.2MPa with the air cylinder of 20mmφ. A piece was prepared and used as a composite 100 for evaluating adhesive strength.
[0209]
Subsequently, the composite 100 for evaluating adhesive strength was left in a test room adjusted to 23 ° C. and 50% RH for 5 hours or more. Subsequently, as shown in FIG. 2, the universal tensile testing machine UTMI type (Orientec Co., Ltd.The composite 100 for bonding strength evaluation composed of the adherend plates 5a and 5b and the adhesive plates 3a and 3b bonded to both ends of the glass plate 1 is set on the chuck of the product (made), and pulled at a deformation rate of 5 mm / min. The adhesive strength at 50 ° C. was measured by tensile shearing in the directions 7a and 7b.
[0210]
Then, when a deviation occurs in the cooling process after bonding, the necessary cooling time in which the deviation does not occur is determined from the change in the cooling time of the bonding strength based on the phenomenon that the adhesion between the adherends decreases and the bonding strength decreases. .
[0211]
As shown in Table 4 and Table 5, in the resin compositions for adhesion of Examples 21 to 34, excellent adhesive strength with a hot melt adhesive was obtained in a short cooling time. On the other hand, in the resin compositions for adhesion of Comparative Examples 21 to 30, it is understood that excellent adhesive strength with the hot melt adhesive cannot be obtained even when a long cooling time is provided.
[0212]
<Adhesive complex and disassembly method thereof>
Hereinafter, although another Example is given and the adhesive complex of this invention and the disassembly method of an adhesive composite are demonstrated in detail, this invention is not limited to these.
[0213]
<Production of various experimental materials>
Various materials in Examples and Comparative Examples were produced by the following methods.
[0214]
(I) Production of adherend plate
30% glass fiber reinforcedPolybutyleneTerephthalate (Toyobo Co., Ltd., EMC430) was processed to produce a 3.2 mm thick ASTM D638 TYPE 1 adherend plate.
[0215]
(Ii) Production of glass plate
A glass window for automobiles having a thickness of 3.4 mm was cut into 30 mm × 80 mm to produce a glass plate for testing.
[0216]
(Iii) Preparation of polyolefin adhesive I
A silane-modified G197 (polyolefin resin made of a polyethylene copolymer blend, manufactured by Kureha Elastomer Co., Ltd., melting point 105 ° C.) was prepared by blending 60% by mass of iron powder having a particle size of 100 μm (ASC100, manufactured by Höganäs). .
[0217]
(Iv) Preparation of polyolefin adhesive II
Silane-modified G197 (polyolefin resin made of polyethylene copolymer blend, manufactured by Kureha Elastomer Co., Ltd., melting point 105 ° C.) and 10% by mass of carbon fiber (manufactured by Toho Rayon Co., Ltd., HTA, average length 3 mm) And produced.
[0218]
(V) Production of polyolefin adhesive III
Silane-modified G197 (polyolefin resin made of polyethylene copolymer blend, manufactured by Kureha Elastomer Co., Ltd., melting point 105 ° C.) was used as it was.
[0219]
(Vi) Production of adhesive sheet
The barrels of the polyolefin adhesives I, II, and III are respectively introduced from the hopper side into an injection molding machine adjusted to 180-200-200 ° C. and injected into a test piece mold adjusted to 40 ° C. Then, adhesive sheets of two kinds of sizes of 100 mm × 100 mm × 1 mm and 100 mm × 100 mm × 3 mm were produced.
[0220]
<Examples 41 to 43, Comparative Examples 41 to 45>
The adhesive composites of Examples 41 to 43 and Comparative Examples 41 to 45 having the combinations shown in Tables 6 and 7 were prepared, and the characteristics and performances of the respective adhesive composites were evaluated by the following characteristic analysis and performance evaluation. Measured by the method. The results are also shown in Table 6 and Table 7.
[0221]
Here, Comparative Examples 41 to 45 could not be disassembled by dielectric heating. Therefore, for comparison, Table 7 shows the dismantling time in the heating furnace 140 ° C. of Comparative Examples 42 to 45.
[0222]
[Table 6]

[0223]
[Table 7]

[0224]
<Characteristic analysis and performance evaluation>
Next, using the adhesive composites of Examples 41 to 43 and Comparative Examples 41 to 45 obtained as described above, Examples 41 to 43 and Comparative Examples 41 to 43 were performed according to the following analysis method and evaluation method. The performance of the adhesive composite obtained in 45 was evaluated. The results are shown in Table 6 and Table 7.
[0225]
(I) Measurement of dielectric loss tangent
First, a test piece having a size of 8 mm × 8 mm × 3 mm was cut out from a sheet of polyolefin adhesives I, II and III of 100 mm × 100 mm × 3 mm. Next, the terminal area Ds connected to the high frequency dielectric heating device (made by Pearl Industry Co., Ltd., impedance analyzer) is 5 cm.²The test piece was sandwiched and fixed between the conductor terminals. And the high frequency electric charge Q of frequency 40MHz was given to the said test piece on 23 degreeC conditions, the potential difference V between terminals was measured, and the dielectric loss tangent was measured from the potential difference V between terminals.
[0226]
(Ii) Measurement of adhesive strength
As shown in FIG. 2, 12.7 mm × 25.4 mm of the straight portion of the adherend plate 5a, 5b and 12.7 mm × 25.4 mm from the 1 mm thick polyolefin adhesive I, II, III sheet. The adhesive plates 3a and 3b were cut and overlapped. This lap portion was set linearly on both ends of a 30 mm × 80 mm glass plate 1. This was sandwiched between clips (manufactured by Lion Corporation, NO. 111) and treated at 140 ° C. for 20 minutes to produce a composite 100 for evaluating adhesive strength.
[0227]
Next, as shown in FIG. 2, the adhesive strength evaluation composite 100 is set on a Tensilon UTM1 chuck with a heating furnace, and tensile shear is performed in the directions of the tensile directions 7a and 7b at a speed of 5 mm / min. Was used to measure the adhesive strength. The test temperature was 23 ° C.
[0228]
(Iv) Measurement of dielectric heating disassembly time and 140 ° C disassembly time
Dielectric heating disassembly time is 5 cm for the terminal area connected to a high frequency dielectric heating device (impedance analyzer, manufactured by Pearl Industry Co., Ltd.)²The various adhesive composites shown in Table 6 and Table 7 are inserted between the conductor terminals, and a high frequency voltage of 40 MHz is applied at 23 ° C. for various oscillation times to melt the adhesive layer and adhere The time until the material was peeled was measured and determined. In addition, the 140 ° C. disassembly time was obtained by installing the various adhesive composites shown in Table 7 in a high temperature bath of 140 ° C., measuring the time until the adhesive layer was melted, and the adherend was peeled off.
[0229]
As shown in Tables 6 and 7, while the adhesive composites of Examples 41 to 43 have excellent adhesive strength, the adhesive layer can be melted and the material to be bonded can be peeled off in a short time by dielectric heating. In contrast, the adhesive composites of Comparative Examples 41 to 45 can melt the adhesive layer and peel the adherend only after a very long dielectric heating and dismantling time, even when processed at a high temperature of 140 ° C. It can be seen that it is. That is, it can be seen that the disassembly time of the bonded composite according to the example of the present invention is significantly shortened as compared with the disassembly at a conventional heating furnace of 140 ° C.
[0230]
It should be understood that the embodiments and examples disclosed herein are illustrative and non-restrictive in every respect. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.
[0231]
【The invention's effect】
From the above results, the resin composition for dielectric heating adhesion of the present invention can be heated and melted by applying a high-frequency voltage for a very short time, and has excellent adhesive strength even at a relatively high temperature. Therefore, the resin composition for dielectric heating adhesion of the present invention can be suitably used as a binder for a hot melt adhesive having the property of being heated and melted by applying a high frequency voltage.
[0232]
The hot melt adhesive of the present invention can be heated and melted by applying a high-frequency voltage for a very short time, and has excellent adhesive strength even at a relatively high temperature. Therefore, by using the hot melt adhesive of the present invention, it is not necessary to use a heating furnace that is required in the conventional hot melt type adhesive, and the manufacturing equipment for products using the hot melt adhesive is made compact and manufactured. The process can be simplified, and the productivity of the production line can be significantly increased. In addition, by using the hot melt adhesive of the present invention after being formed into a sheet shape, uniform and excellent adhesive strength can be obtained by applying a high-frequency voltage for a very short time even in the bonding process between large members. .
[0233]
And the adhesion | attachment method of the to-be-adhered materials of this invention can implement | achieve the outstanding adhesive strength by the application of the high frequency voltage for a very short time. Therefore, by using the bonding method between the adherends of the present invention, it is not necessary to use a heating furnace that is required in the bonding method using the conventional hot melt type adhesive, and the hot melt adhesive is used. The manufacturing equipment for products manufactured by the bonding method can be made compact and the manufacturing process can be simplified, and the productivity of the manufacturing line can be remarkably increased. In addition, by using the bonding method between adherends of the present invention, uniform and excellent bonding strength can be obtained by applying a high-frequency voltage for a very short time even in a bonding process between large members.
[0234]
Further, from the above results, the resin composition for adhesion of the present invention is excellent in being hard to melt or soften by heating of the hot melt adhesive and re-cured in a short time when bonded by the hot melt adhesive. It is the resin composition for to-be-adhered used as a to-be-adhered material of a hot-melt-adhesive which shows the adhesiveness.
[0235]
Furthermore, from the above results, the bonded composite of the present invention can be disassembled in a short time by applying a high-frequency voltage without using a heating furnace, and the high-frequency voltage applied so that the material of the adherend can be reused well. It is an adhesive complex that can be disassembled by doing.
[0236]
From the above results, the method of disassembling the adhesive composite of the present invention can save energy, time and labor during disassembly by efficiently heating only the adhesive part of the adhesive composite. This is a method for disassembling an adhesive complex.
[0237]
Therefore, the method for disassembling the adhesive composite of the present invention does not use a heating furnace, can be disassembled in a short time, and only the adhesive layer is selectively heated and melted, saving energy required for disassembly. Can be realized. In addition, since the method for disassembling an adhesive composite according to the present invention has a low degree of material breakage and deterioration, it is possible to collect large-sized members and contribute to the industry.
[Brief description of the drawings]
FIG. 1 is a step diagram showing an outline of a method for disassembling an adhesive composite according to the present invention.
FIG. 2 is a schematic view showing an example of a method for measuring the adhesive strength of an adhesive composite.
[Explanation of symbols]
1 Glass plate, 3a, 3b Adhesive plate, 5a, 5b Adhered material plate, 7a, 7b Tensile direction, 100 Composite for evaluating adhesive strength.

Claims (16)

It contains a polyolefin resin having a melting point of 80 to 200 ° C. and a conductive material having a volume resistivity of 10 ⁻² Ω · cm or less, and the content of the conductive material with respect to the entire resin composition is 1 to 30. A resin composition for dielectric heating bonding of a material to be bonded, in which at least one has a dielectric loss tangent of 0.03 or more at a frequency of 40 MHz and a 23 ° C. condition at a frequency of 40 MHz, which is made of glass or ceramic .   2. The resin composition for dielectric heating bonding according to claim 1, wherein a dielectric loss tangent at 23 ° C. at a frequency of 40 MHz is 0.1 or more. 3. The resin composition for dielectric heating adhesion according to claim 1, wherein the conductive material has a volume resistivity of 10 ⁻⁴ Ω · cm or less.   The conductive material is selected from the group consisting of iron, copper, silver, an alloy containing iron as a main component, an alloy containing copper as a main component, an alloy containing silver as a main component, carbon, and an inorganic compound containing carbon as a main component. The resin composition for dielectric heating bonding according to any one of claims 1 to 3, wherein the resin composition contains one or more materials.   The conductive material has one or more shapes selected from the group consisting of powder, granule, granule, needle, fiber, and scale, and is uniformly dispersed in the resin composition for dielectric heating adhesion The resin composition for dielectric heating bonding according to any one of claims 1 to 4, wherein the resin composition is contained in a state of being made.   The resin composition for dielectric heating adhesion according to any one of claims 1 to 5, wherein the resin composition is heated and melted by applying a high-frequency voltage and then solidified by cooling and exhibits adhesiveness.   The frequency is in the range of 1 to 5000 MHz, the high frequency voltage in the range of 0.1 to 100 kW is applied in the range of 1 to 1000 seconds, and the mixture is heated and melted. The resin composition for dielectric heating adhesion in any one.   A hot melt adhesive containing the resin composition for dielectric heating adhesion according to claim 1.   The hot melt adhesive according to claim 8 sandwiched between the adherends, the frequency is in the range of 1 to 5000 MHz, and the high frequency voltage in the range of high frequency output 0.1 to 100 kW is 1 to 1000. A method for adhering an adherend, comprising a step of heating and melting by applying in a range of seconds. An adhesive composite comprising a hot-melt adhesive and at least one bonded at the joint by the hot-melt adhesive is a glass or ceramic material , wherein the hot-melt adhesive is a dielectric A hot-melt adhesive containing a heat-bonding resin composition and heated and melted by applying a high-frequency voltage, the dielectric heat-bonding resin composition having a melting point in the range of 60 to 200 ° C. And a conductive material having a volume resistivity of 10 ⁻² Ω · cm or less, and a dielectric tangent at 23 ° C. at a frequency of 40 MHz is 0.03 or more. The content of the conductive material in the dielectric heating adhesive resin composition is in the range of 1 to 30% by volume, and can be disassembled by applying a high-frequency voltage. Body. The adhesive composite according to claim 10 , wherein the dielectric tangent of the resin composition for dielectric heating adhesion at a frequency of 40 MHz under a condition of 23 ° C is 0.1 or more. The adhesion composite according to claim 10 or 11 whose volume resistivity of said conductive material is 10 <^-4> ohm * cm or less. The conductive material is selected from the group consisting of iron, copper, silver, an alloy containing iron as a main component, an alloy containing copper as a main component, an alloy containing silver as a main component, carbon, and an inorganic compound containing carbon as a main component. The adhesive composite according to any one of claims 10 to 12 , comprising one or two or more materials. The conductive material has one or more shapes selected from the group consisting of powder, granule, granule, needle, fiber, and scale, and is uniform in the resin composition for dielectric heating adhesion The adhesive composite according to any one of claims 10 to 13 , which is contained in a dispersed state. The adhesion composite according to any one of claims 10 to 14 , wherein a dielectric loss tangent at 23 ° C at a frequency of 40 MHz of the adherend is in a range of 0 to 0.1. The adhesive composite according to any one of claims 10 to 15 , wherein a dielectric loss tangent of the resin composition for dielectric heating adhesion at a frequency of 40 MHz is greater than twice a dielectric loss tangent of the adherend at a frequency of 40 MHz.

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