JP4034911B2

JP4034911B2 - Interlayer film for laminated glass and laminated glass

Info

Publication number: JP4034911B2
Application number: JP20765399A
Authority: JP
Inventors: 誠稲永; 隆信鈴木
Original assignee: Mitsubishi Plastics Inc
Current assignee: Mitsubishi Plastics Inc
Priority date: 1999-07-22
Filing date: 1999-07-22
Publication date: 2008-01-16
Anticipated expiration: 2019-07-22
Also published as: JP2001031451A

Description

【０００１】
【発明の属する技術分野】
本発明は、オートクレーブによる高温・高圧処理を必要とせず、室温で合わせ加工が可能な合わせガラス用中間膜及び合わせガラスに関するものである。
【０００２】
【従来の技術】
合わせガラスは、自動車用安全ガラス、公共施設や運動施設等のグレージング材、間仕切り、防犯用ドア等に広く用いられ、その構造としては、通常、複数枚の無機ガラス板（以下、「ガラス板」という）又は一部のガラス板を透明な合成樹脂板に替え、各々のガラス板同士又はガラス板と合成樹脂板の間に中間膜を介して合わせ加工した構成となっている。
【０００３】
このような中間膜としては、可塑剤により可塑化されたポリビニルブチラール（ＰＶＢ）が、ガラス板や合成樹脂板との優れた接着性、強靭な引張強度、高い透明性等を兼ね備えているため、最も一般的に用いられている。
【０００４】
しかしながら、上記ＰＶＢ樹脂からなる熱可塑性樹脂中間膜は、合わせガラスを製造する際、加熱仮接着した後、オートクレーブを用い高温・高圧条件下で行う必要があり、作業が煩雑になるという問題があった。
【０００５】
ここで、合わせガラスに合成樹脂板を使用したものでは、上記ＰＶＢ樹脂に使用した可塑剤が中間膜と合成樹脂板との界面に吹出し（ブリードアウト）、接着力を低下させたり、合成樹脂板の白化やクラックの原因になることがあり、さらにガラス板と合成樹脂板とでは線膨脹係数が異なるため高温条件下で合わせ加工した場合、合わせガラスが反ったり、割れ易いという問題があった。
【０００６】
上記問題点を解決するための手段として、ＰＶＢ樹脂に代えて、エチレン−（メタ）アクリル酸エステル共重合体を中間膜に使用することが提案され（特開平８一１８８４５３号公報）、また、液状樹脂をガラス板の間に注入した後、室温で硬化させる方法が提案されている（特開平７一２９０６４７号公報）。
【０００７】
【発明が解決しようとする課題】
しかしながら、エチレン−（メタ）アクリル酸エステル共重合体からなる中間膜を使用すると、オートクレーブ処理問題と、可塑剤による問題を解決できるが、真空条件下での仮接着工程と１１０℃以上の合わせ加工温度を必要とするために、合成樹脂板との合わせガラスでは、反りや割れの問題は解決できず、また、上記の液状樹脂を用いた方法では、室温で硬化させるので、反りや割れの問題を解決できるが、樹脂の注入方法や膜厚制御が容易でないという問題がある。
【０００８】
本発明は前記従来の問題点に鑑みてなされたものであって、その第１の目的は加熱仮接着、オートクレーブによる高温・高圧処理を必要とすることなく、室温で合わせ加工可能な合わせガラス用中間膜を提供することにあり、第２の目的はその中間膜を使用した合わせガラスを提供することにある。
【０００９】
【課題を解決するための手段】
前記第１の目的を達成するため、請求項１に記載の発明では、合わせガラス用中間膜において、ガラス板との接合後、気泡のない外観を得るために、下記（ａ）及び（ｂ）の粘弾性特性を有する感圧接着剤で形成された平面状の感圧接着剤層を少なくとも１層設けた。
【００１０】
（ａ）測定温度２０°Ｃ、周波数１Ｈｚでの貯蔵弾性率Ｇ’（１Ｈｚ）が５×１０³〜５×１０⁵Ｐａ（パスカル）。
（ｂ）基準温度２０°Ｃ、周波数１０^-7Ｈｚでの貯蔵弾性率Ｇ’（１０^-7Ｈｚ）が５×１０¹〜５×１０³Ｐａ。
【００１１】
粘弾性特性はレオメトリックス社製の粘弾性測定装置ダイナミックアナライザーＲＤＡIIを用いて以下の条件で測定した。
・温度：２０〜１５０°Ｃ
・角振動数：ω＝０．００５〜５００ｒａｄ／ｓｅｃ
・パラレルプレート：２５ｍｍφ
・歪み量：３％
ＲＡＤIIで２０°Ｃを基準温度として温度−時間換算のマスターカーブを作成し、（ａ）及び（ｂ）の周波数ｆ値はｆ（Ｈｚ）＝ω／（２π）より算出し、それぞれ貯蔵弾性率Ｇ’を読み取った。
【００１２】
請求項２に記載の発明では、請求項１に記載の発明において、前記中間膜は表裏両側に感圧接着剤層の接着面が存在する。
請求項３に記載の発明では、請求項１又は請求項２に記載の発明において、前記中間膜は接着面に離型フィルムが付着されている。
【００１３】
感圧接着剤層が１層の場合はその表裏両面に離型フィルムが貼付されて中間膜が形成される。また、中間膜の取扱い性（作業性）を良くするため、芯材として高剛性フィルムやシートを挟んで両側に感圧接着剤層が形成される場合は、感圧接着剤層が複数層形成される。
【００１４】
請求項４に記載の発明では、請求項１〜請求項３のいずれか一項に記載の発明において、前記（ａ）及び（ｂ）の粘弾性特性を有する感圧接着剤層の厚みが０．０５〜２ｍｍである。
【００１５】
請求項５に記載の発明では、請求項１〜請求項４のいずれか一項に記載の発明において、基準温度２０°Ｃ、周波数１０^-7Ｈｚでの貯蔵弾性率Ｇ’（１０^-7Ｈｚ）と、前記（ａ）及び（ｂ）の粘弾性特性を有する感圧接着剤層の厚みｔ（ｍｍ）との比：Ｇ’（１０^-7Ｈｚ）／ｔが２５〜１×１０⁵である。
【００１６】
請求項６に記載の発明では、請求項１〜請求項５のいずれか一項に記載の発明において、前記（ａ）及び（ｂ）の粘弾性特性を有する感圧接着剤がアクリル系感圧接着剤である。
【００１７】
また、第２の目的を達成するため、請求項７に記載の発明の合わせガラス板は、請求項１〜請求項６のいずれか一項に記載の中間膜を用いてガラス板同士、ガラス板と合成樹脂板又は合成樹脂板同士を少なくとも２枚接合してなる。
【００１８】
従って、請求項１に記載の発明では、中間膜が特定範囲の粘弾性特性を有する感圧接着剤で形成されることにより、合わせ加工後のガラス板及び感圧接着剤層自体の厚みの不均一による界面の凹凸を埋めるような流動（濡れ）が進行する。しかし、感圧接着剤層の経時的な寸法安定性は確保される。
【００１９】
請求項２に記載の発明では、請求項１に記載の発明において、前記中間膜は表裏両側に感圧接着剤層の接着面が存在するため、他の感圧接着剤を使用することなく当該中間膜を使用するだけで室温で合わせ加工を行うことができる。
【００２０】
請求項３に記載の発明では、請求項１又は請求項２に記載の発明において、中間膜は表裏両接着面に離型フィルムが付着されているため、中間膜同士を重ねて保管でき、中間膜の保管スペースが小さくて済む。また、使用時には離型フィルムを剥がすことにより簡単に接着面が露出する。
【００２１】
請求項４に記載の発明では、請求項１〜請求項３のいずれか一項に記載の発明において、感圧接着剤層の厚みが０．０５〜２ｍｍのため、ガラス板及び中間膜の表面の凹凸に確実に対応してガラス板に対する接着性が良好に確保されるとともに、感圧接着剤層を形成するための感圧接着剤の量が過多とならない。
【００２２】
請求項５に記載の発明では、請求項１〜請求項４のいずれか一項に記載の発明において、感圧接着剤の貯蔵弾性率Ｇ’（１０^-7Ｈｚ）の大きさでガラス板及び中間膜の表面の凹凸部への馴染み易さが変わるが、感圧接着剤の貯蔵弾性率Ｇ’（１０^-7Ｈｚ）と感圧接着剤層の厚みｔ（ｍｍ）との比：Ｇ’（１０^-7Ｈｚ）／ｔが２５〜１×１０⁵のため、馴染み易くなる。
【００２３】
請求項６に記載の発明では、請求項１請求項１〜請求項５のいずれか一項に記載の発明において、感圧接着剤がアクリル系感圧接着剤であるため、耐候性や透明性が良くなる。
【００２４】
請求項７に記載の発明の合わせガラス板は、請求項１〜請求項６のいずれか一項に記載の中間膜を用いてガラス板同士、ガラス板と合成樹脂板又は合成樹脂板同士を接合して構成されるため、オートクレーブを用いずに接合できる。
【００２５】
【発明の実施の形態】
以下、本発明を具体化した一実施の形態を説明する。
図１に示すように、中間膜１は感圧接着剤層２と、その表裏両接着面に付着された離型フィルム３とから構成されている。感圧接着剤層２は下記（ａ）及び（ｂ）の粘弾性特性を有する感圧接着剤で構成されている。（ａ）測定温度２０°Ｃ、周波数１Ｈｚでの貯蔵弾性率Ｇ’（１Ｈｚ）が５×１０³〜５×１０⁵Ｐａ（パスカル）。（ｂ）基準温度２０°Ｃ、周波数１０^-7Ｈｚでの貯蔵弾性率Ｇ’（１０^-7Ｈｚ）が５×１０¹〜５×１０³Ｐａ。
【００２６】
感圧接着剤層２は厚みｔが０．０５〜２ｍｍが好ましい。厚みが０．０５ｍｍ未満では接着性が劣り易くなり、２ｍｍを超えるとコスト面で問題がある。厚みが０．０５〜２ｍｍであれば、ガラス板同士、ガラス板と合成樹脂板又は合成樹脂板同士を接合して合わせガラスを製造する際、ガラス板、合成樹脂板及び感圧接着剤層２自身の表面の凹凸に確実に対応してガラス板及び合成樹脂板に対する接着性が良好に確保されるとともに、感圧接着剤層２を形成するための感圧接着剤の量が過多とならない。
【００２７】
感圧接着剤の基準温度２０°Ｃ、周波数１０^-7Ｈｚでの貯蔵弾性率Ｇ’（１０^-7Ｈｚ）と、感圧接着剤層２の厚みｔ（ｍｍ）との比：Ｇ’（１０^-7Ｈｚ）／ｔが２５〜１×１０⁵に設定されている。
【００２８】
従来の合わせガラス用中間膜は、加熱溶融させ２枚のガラス板の凹凸を埋めるようなホットメルトタイプであるのに対して、本発明の中間膜は室温で接着可能な粘弾性特性を有する感圧接着剤を用いたものである。
【００２９】
本発明の中間膜に用いる感圧接着剤では、長時間域の貯蔵弾性率を特定の範囲で制御することで適度に緩和する。従って、合わせ加工時に変形した感圧接着剤は、合わせ後に厚みの凹凸に馴染んで緩和し、気泡のない合わせ外観を得ることができる。
【００３０】
即ち、周波数１０^-7Ｈｚの貯蔵弾性率Ｇ’（１０^-7Ｈｚ）が５×１０¹〜５×１０³Ｐａの範囲であることが重要である。貯蔵弾性率Ｇ’（１０^-7Ｈｚ）が５×１０¹Ｐａ未満では流動しすぎて合わせガラス加工後、中間膜がはみ出たり、ガラス板等がずれるという問題があり、５×１０³Ｐａを超えると合わせガラスに加工後、硬すぎて中間膜の僅かな厚みむらの凹凸により、凹部に気泡が発生するという問題がある。また、貯蔵弾性率Ｇ’（１Ｈｚ）が５×１０³〜５×１０⁵Ｐａの範囲であることも、常温貼り合わせ加工において重要である。即ち、貯蔵弾性率Ｇ’（１Ｈｚ）が５×１０³Ｐａ以下である場合は、貼り合わせ直後の形状保持が難しく、貯蔵弾性率Ｇ’（１Ｈｚ）が５×１０⁵Ｐａ以上である場合は、ガラス板又は合成樹脂板との濡れ性が悪く十分な接着力を確保できない。
【００３１】
感圧接着剤層２を形成する感圧接着剤は、前記粘弾性特性を満足するものであれば適宜選択できるが、耐候性及び透明性の良いアクリル系感圧接着剤を用いるのが好ましい。アクリル系感圧接着剤としてはエチレンとα，β不飽和カルボン酸を含有した（メタ）アクリル酸エステル共重合体に金属化合物等を添加して金属イオン架橋したアイオノマー樹脂がある。金属化合物としては、亜鉛イオン、ナトリウムイオンなどを有するアセチルアセトン金属錯体、金属酸化物、脂肪酸金属塩等を用いる。アイオノマー樹脂は既にイオン架橋したものを使用してもよいが、中間膜の製造時に共重合体へ金属化合物を添加してイオン架橋させたものの方が好ましい。
【００３２】
次に前記中間膜１を使用して合わせガラスを製造する方法を図２に従って説明する。合わせ加工には種々の方法があるが、オートクレーブを用いずに接合できる次の方法が好適である。合わせガラスはガラス板同士、ガラス板と合成樹脂板又は合成樹脂板同士を接合する場合とがあるが、この実施の形態ではガラス板と合成樹脂板とを接合する。
【００３３】
図２（ａ）に示すように、先ずガラス板４又は合成樹脂板５のいずれか一方（この実施の形態ではガラス板４）に、片面の離型フィルム３を剥がした中間膜１をニップロール６と駆動ゴムロール７間で、初めて接触するようにロール間へ搬入し、ガラス板４の表面に中間膜１を貼付する。次に残りの離型フィルム３を剥がし、図２（ｂ）に示すように、中間膜１が貼付されたガラス板４を中間膜１を介して合成樹脂板５と接触させずに向かい合わせ、２枚の板の端部をニップロール６と駆動ゴムロール７間で、初めて接触するようにニップロール６に挟んで両方の板を連続して接合させると、合わせガラス８が完成する。
【００３４】
この方法では、ニップロール６の線圧力により、合成樹脂板５と中間膜１の間に気泡をかみ込むことなく接着できる。つまり、線圧力によって短時間で与えられた中間膜１の歪みは回復しようとするため、まだ接着されていないニップロール直前の合成樹脂板５を僅かに湾曲させ、２枚の板の間に隙間を常に生じさせ気抱を押出すことができる。上記方法は、本発明の中間膜１の粘弾性特性を利用することで、従来の減圧脱泡・仮接着及びオートクレーブによる高温・高圧処理が不要となり、室温での作業が可能となり、得られる合わせガラス８も気泡が入らず品質上優れたものとなる。
【００３５】
以下、実施例及び比較例により、更に詳しく説明する。
（実施例１）
アクリル酸エステル共重合体を金属化合物で架橋させ、表裏両面に離型フィルム３を貼付した厚さ１．０ｍｍのアクリル系感圧接着シートを中間膜１として用いた。
【００３６】
前記アクリル酸エステル共重合体は、ｎ−ブチルアクリレート：７８．４重量％、２−エチルヘキシルアクリレート：１９．６重量％及びアクリル酸：２．０重量％を共重合させたもので、アクリル酸エステル共重合体のＧＰＣで測定した分子量及び分子量分布は、重量平均分子量（ＭＷ）：２．２７×１０⁶、重量平均分子量（ＭＷ）／数平均分子量（ＭＮ）：３．６であった。
【００３７】
前記アクリル系感圧接着シートはアクリル酸エステル共重合体１００重量部に対し、金属化合物としてアセチルアセトン亜鉛塩：０．５重量部及びアセチルアセトンアルミ塩：０．７重量部を溶融攪拌した後、離型フィルム間に所定厚み（１．０ｍｍ）でシート状に成形して得た。
【００３８】
市販のフロートガラス板（厚さ３ｍｍ、幅２００ｍｍ、長さ３００ｍｍ）の一方の面に、片面の離型フィルムを剥がした中間膜をニップロールと駆動ゴムロール間で、初めて接触するようにロール間へ搬入させ、紙圧力：ｌｋｇｆ／ｃｍ、速度：５ｍ／分）で貼った後、残りの雛型フィルムを剥がした。
【００３９】
次に前記中間膜を貼ったガラス板を中間膜を介して市販のポリカーボネート板（厚さ２ｍｍ、幅２００ｍｍ、長さ３００ｍｍ、ＵＶカット、ハードコート処理）を接触させずに向かい合わせ、２枚の板の端部をニップロールと駆動ゴムロール間で、初めて接触するようにニップロール（線圧力：２０ｋｇｆ／ｃｍ、速度０．５ｍ／分）に挟んで合わせガラスを得た。
【００４０】
（実施例２）
実施例１で得た未架橋のアクリル酸エステル共重合体を酢酸エチルで固形分４０重量％に調整した溶液：１００重量部に対し、架橋剤としてトリレンジイソシアネート（ＴＤＩ）を酢酸エチルで２５重量％に調整した溶液：２．０重量部を混合攪拌して、離型フィルムに任意の厚みに塗工し、溶剤を乾燥後、重ね合わせて厚み１．０ｍｍの感圧接着剤層が離型フィルム間に挟まれた中間膜を得た。この中間膜を使用し、実施例１と同様の条件で合わせガラスを作製した。
【００４１】
（比較例１）
実施例１で得た未架橋のアクリル酸エステル共重合体を酢酸エチルで固形分４０重量％に調整した溶液：１００重量部に対し、架橋剤としてトリレンジイソシアネート（ＴＤＩ）を酢酸エチルで２５重量％に調整した溶液：９．０重量部を混合攪拌して、離型フィルムに任意の厚みに塗工し、溶剤を乾燥後、重ね合わせて厚み１．０ｍｍの感圧接着剤層が離型フィルム間に挟まれた中間膜を得た。この中間膜を使用し、実施例１と同様の条件で合わせガラスを作製した。
【００４２】
（比較例２）
実施例１で得た未架橋のアクリル酸エステル共重合体を離型フィルム間にシート状に成形して厚み１．０ｍｍの中間膜を得た。合わせガラスの作製方法は実施例１と同様の条件で行った。
【００４３】
次に前記実施例及び比較例により得られた各々の合わせガラスを用いて、下記の項目について評価した。結果を表１に示した。問題がなかったものは（○）で示している。
【００４４】
［合わせ直後］：合わせガラス作製直後の外観（気泡、剥離、板のずれ、中間膜のはみ出し等の有無）を観察した。
［合わせ後１日］：合わせガラス作製後から合わせガラスを４５°に傾斜させた状態で４０°Ｃ×１日後の外観（気泡、剥離、板のずれ、中間膜のはみ出し等の有無）を観察した。
観察した。
【００４５】
【表１】

表１の結果から明らかなように、本発明の中間膜を用いた場合、室温での合わせ加工が可能で外観上満足できる合わせガラスを得ることができるのに対し、粘弾性特性が本発明の周波数で測定した貯蔵弾性率の範囲外である感圧接着剤から構成された中間膜を用いた合わせガラスでは、観察項目のいずれかを満足することができないことが判る。
【００４６】
この実施の形態では次の効果を有する。
（１）中間膜１が感圧接着剤層２と離型フィルム３とで構成され、中間膜は表裏両側に感圧接着剤層２の接着面が存在する構成のため、離型フィルム３を剥がして使用することにより、加熱仮接着、オートクレーブによる高温・高圧処理を必要とすることなく、室温でガラス板４同士、ガラス板４と合成樹脂板５あるいは合成樹脂板５同士の合わせ加工が可能となる。
【００４７】
（２）長時間域の貯蔵弾性率が特定の範囲にあるため、合わせ加工時に変形した感圧接着剤層が、合わせ後に厚みの凹凸に馴染んで緩和し、気泡のない合わせ外観を得ることができる。
【００４８】
（３）感圧接着剤層２の厚みが０．０５〜２ｍｍのため、ガラス板４、合成樹脂板５及び中間膜１の表面の凹凸に確実に対応してガラス板４及び合成樹脂板５に対する接着性が良好に確保されるとともに、感圧接着剤層２を形成するための感圧接着剤の量が過多とならない。
【００４９】
（４）感圧接着剤の貯蔵弾性率Ｇ’（１０^-7Ｈｚ）の大きさでガラス板４、合成樹脂板５及び中間膜１の表面の凹凸部への馴染み易さが変わるが、感圧接着剤の貯蔵弾性率Ｇ’（１０^-7Ｈｚ）と感圧接着剤層２の厚みｔ（ｍｍ）との比：Ｇ’（１０^-7Ｈｚ）／ｔが２５〜１×１０⁵のため、馴染み易くなる。
【００５０】
（５）感圧接着剤がアクリル系感圧接着剤であるため、耐候性や透明性が良くなる。
（６）中間膜１は表裏両接着面に離型フィルム３が貼付された構成のため、一方の離型フィルム３を剥がした状態で先ずガラス板４及び合成樹脂板５の一方に作業性良く貼付でき、次に他方の離型フィルム３を剥がしてガラス板４及び合成樹脂板５の他方に作業性良く貼付できる。また、感圧接着剤を直接ガラス板４又は合成樹脂板５に塗布して感圧接着剤層２を形成する場合に比較して、所定の厚さに形成するのが容易になる。
【００５１】
実施の形態は前記に限定されるものではなく、例えば、次のように具体化してもよい。
○ 中間膜１は感圧接着剤層２が１層に限らず、例えば、図３（ａ）に示すように、フィルム、シートあるいは繊維で形成された網状のものを芯材９とし、その両側に感圧接着剤層２が形成された構成としてもよい。この場合、剛性の高い二軸延伸ポリエチレンテレフタレートフィルムなどを用いると特に中間膜１の取扱い性（作業性）が良くなる。また、中間膜１の両側にガラス板４を貼り合わせた構成の合わせガラス８を製造する場合、図３（ｂ）に示すように、中間膜１の芯材９としてポリカーボネート板等の板材、あるいはポリウレタン，ポリビニルブチラール，エチレン−酢酸ビニル共重合体などからなる伸びの大きいフィルムを使用してもよい。この場合、合わせガラス８の耐衝撃性や耐貫通性が向上する。即ち、本願発明では中間膜１とはある程度の可撓性を有する薄い平面状のものを意味する。
【００５２】
○ 前記粘弾性特性を有する感圧接着剤層２は少なくとも１層存在すればよく、中間膜１の構成として、例えば、図４（ａ）に示すように、前記粘弾性特性を有する感圧接着剤層２と本発明以外の感圧接着剤層１０又は中間膜とが２層に積層されたもの、感圧接着剤層２と板、シート、フィルム、繊維等の平面状の補強材１１とが２層に積層されたものとしてもよい。また、図４（ｃ）に示すように、感圧接着剤層２を挟んで両側に本発明以外の感圧接着剤層１０又は中間膜が積層された構成としてもよい。
【００５３】
本願発明の感圧接着剤層２以外の感圧接着剤層１０（あるいは合わせる板）の表面に凹凸がある場合、本願発明以外の感圧接着剤層１０のみでは比較例にあるように、貼り合わせ後に弾性回復して気泡を生じるが、本願発明の感圧接着剤層２が１層以上存在すれば、図５に示すように、表裏層の本願発明以外の感圧接着剤層１０の凹凸１２が内部、即ち本願発明の感圧接着剤層２で緩和され、気泡の発生が防止される。
【００５４】
中間膜１の外面に感圧接着剤層２又は感圧接着剤層１０がない構成の場合、室温で合わせ加工するには合わせる板の面に感圧接着剤を塗布して合わせ加工を行う。また、加熱は必要とするがオートクレーブを必要とするような高温・高圧の条件は不要な接着剤（例えば、従来のエチレン−（メタ）アクリル酸エステル共重合体のような接着剤）を使用して合わせ加工を行ってもよい。この場合、加熱接着で貼り合わせを行っても、本願発明の感圧接着剤層２が存在することによって、両側の板の線膨張率の相違による寸法変化を吸収し、反り等を防ぐことができる。
【００５５】
本願発明の感圧接着剤層２と他の感圧接着剤層１０とを積層した場合、ガラス板４あるいは合成樹脂板５と感圧接着剤層との界面接着強度を調整することができる。即ち、本願発明の感圧接着剤よりガラス板４あるいは合成樹脂板５に対する接着強度が大きな感圧接着剤層１０でガラス板４あるいは合成樹脂板５に対する接着強度を確保し、合わせ加工時の変形応力の緩和を本願発明の感圧接着剤層２が受け持つことで適正な接着力の中間膜が得られる。
【００５６】
○ 中間膜１を使用して合わせガラス８を製造する方法として、ガラス板４及び合成樹脂板５の一方に中間膜１を貼付して感圧接着剤層２を形成し、次いで他方のガラス板４又は合成樹脂板５を感圧接着剤層２の上に載置した状態で減圧タンク内にいれ、タンク内を減圧にして感圧接着剤層２とガラス板４又は合成樹脂板５との間に残存する空気層を排出した後、プレスして貼り合わせてもよい。
【００５７】
○ 中間膜１を構成する感圧接着剤を直接ガラス板４又は合成樹脂板５の表面に塗布して所定の厚さの感圧接着剤層２を形成してもよい。しかし、離型フィルム３に挟んだ状態でシート状に形成する方が、所定の厚さの感圧接着剤層２を形成するのが容易になる。
【００５８】
○ 合わせガラスを構成するガラス板及び合成樹脂板の合計枚数は２枚に限らず、３枚以上としてもよい。
○ 合成樹脂板５としてＰＣ板に代えて、アクリル板、硬質ポリ塩化ビニル板、ポリエステル板などを使用してもよい。
【００５９】
○ また、表裏両側に感圧接着剤層の接着面が存在する構成の中間膜の場合は、他の感圧接着剤を使用せずに表面の離型フィルムを剥がすだけで、合わせ加工ができる。従って、そのような構成の中間膜は太陽電池の表面保護ガラスとシリコンセルとの間の接着、充填材料等の加熱を嫌う用途に好適に用いることができる。
【００６０】
前記実施の形態から把握できる請求項記載以外の技術的思想（発明）について、以下にその効果とともに記載する。
（１）請求項２に記載の発明において、前記感圧接着剤層はフィルム状の芯材の両面に形成されている。この場合、中間膜の取扱い性（作業性）が良くなる。
【００６１】
（２）請求項６に記載の発明において、前記合成樹脂板にはポリカーボネート板が使用されている。この場合、厚みが薄くて耐衝撃性及び耐熱性に優れた板を入手し易く、合わせガラスの薄肉化に寄与する。
【００６２】
【発明の効果】
以上詳述したように請求項１〜請求項７に記載の発明によれば、加熱仮接着、オートクレーブによる高温・高圧処理を必要とすることなく、室温でガラス板同士あるいはガラス板と合成樹脂板との合わせ加工が可能となる。
【００６３】
請求項２に記載の発明によれば、他の感圧接着剤を使用することなく当該中間膜を使用するだけで室温で合わせ加工を行うことができる。また、太陽電池の表面保護ガラスとシリコンセルとの間の接着、充填材料等の加熱を嫌う用途に好適に用いることができる。
【００６４】
請求項３に記載の発明によれば、合わせガラスを製造する際、ガラス板又は合成樹脂板の表面に感圧接着剤層を作業性良く所定の厚さに形成することができる。
【００６５】
請求項４に記載の発明によれば、感圧接着剤層のガラス板及び合成樹脂板に対する接着性が良好に確保されるとともに、感圧接着剤層を形成するための感圧接着剤の量が過多とならない。
【００６６】
請求項５に記載の発明によれば、ガラス板、合成樹脂板及び中間膜の表面の凹凸部へ感圧接着剤が馴染み易くなる。
請求項６に記載の発明によれば、耐候性や透明性が良くなる。
【図面の簡単な説明】
【図１】中間膜の模式断面図。
【図２】合わせガラスの製造方法の一例を示す工程概略図。
【図３】（ａ）は別の実施の形態の中間膜の模式断面図、（ｂ）は別の実施の形態の中間膜を使用して製造した合わせガラスの模式断面図。
【図４】別の実施の形態の中間膜の模式断面図。
【図５】別の実施の形態の中間膜の作用を説明する模式断面図。
【符号の説明】
１…中間膜、２…感圧接着剤層、３…離型フィルム、４…ガラス板、５…合成樹脂板、８…合わせガラス。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an interlayer film for laminated glass and laminated glass that can be laminated at room temperature without requiring high-temperature and high-pressure treatment by an autoclave.
[0002]
[Prior art]
Laminated glass is widely used for safety glass for automobiles, glazing materials for public facilities and sports facilities, partitions, security doors, etc., and usually has a plurality of inorganic glass plates (hereinafter “glass plates”). Or a part of the glass plate is replaced with a transparent synthetic resin plate, and each glass plate or the glass plate and the synthetic resin plate are combined and processed through an intermediate film.
[0003]
As such an intermediate film, polyvinyl butyral (PVB) plasticized with a plasticizer combines excellent adhesion with a glass plate or a synthetic resin plate, tough tensile strength, high transparency, etc. Most commonly used.
[0004]
However, the thermoplastic resin intermediate film made of the PVB resin has a problem in that it is necessary to carry out under high temperature and high pressure conditions using an autoclave after temporary heating and bonding, when manufacturing laminated glass. It was.
[0005]
Here, in the case where a synthetic resin plate is used for the laminated glass, the plasticizer used in the PVB resin blows out to the interface between the intermediate film and the synthetic resin plate to reduce the adhesive force, or the synthetic resin plate. In addition, the glass plate and the synthetic resin plate have different linear expansion coefficients, so that when laminated together under high temperature conditions, the laminated glass is warped or easily broken.
[0006]
As a means for solving the above problems, it has been proposed to use an ethylene- (meth) acrylic acid ester copolymer as an intermediate film instead of PVB resin (Japanese Patent Laid-Open No. Hei 8-188453), There has been proposed a method in which a liquid resin is injected between glass plates and then cured at room temperature (Japanese Patent Application Laid-Open No. 7-290647).
[0007]
[Problems to be solved by the invention]
However, the use of an intermediate film made of an ethylene- (meth) acrylic acid ester copolymer can solve the autoclave treatment problem and the plasticizer problem. Because of the need for temperature, the laminated glass with a synthetic resin plate cannot solve the problem of warping and cracking, and the method using the above liquid resin is cured at room temperature. However, there is a problem that the resin injection method and the film thickness control are not easy.
[0008]
The present invention has been made in view of the above-mentioned conventional problems. The first object of the present invention is for laminated glass that can be laminated at room temperature without requiring high-temperature and high-pressure treatment by heat temporary bonding or autoclave. The second object is to provide a laminated glass using the intermediate film.
[0009]
[Means for Solving the Problems]
To achieve the first object, in the invention according to claim 1, in the interlayer film for a laminated glass, after the bonding of the glass plate, in order to obtain the appearance have the name of the bubble, following (a) and ( At least one planar pressure-sensitive adhesive layer formed of the pressure-sensitive adhesive having the viscoelastic property of b) was provided.
[0010]
(A) Storage elastic modulus G ′ (1 Hz) at a measurement temperature of 20 ° C. and a frequency of 1 Hz is 5 × 10 ^{3 to} 5 × 10 ⁵ Pa (pascal).
(B) Storage elastic modulus G ′ (10 ⁻⁷ Hz) at a reference temperature of 20 ° C. and a frequency of 10 ⁻⁷ Hz is 5 × 10 ^{1 to} 5 × 10 ³ Pa.
[0011]
The viscoelastic properties were measured under the following conditions using a viscoelasticity measuring apparatus dynamic analyzer RDAII manufactured by Rheometrics.
・ Temperature: 20 ~ 150 ° C
Angular frequency: ω = 0.005 to 500 rad / sec
・ Parallel plate: 25mmφ
・ Distortion amount: 3%
Create a temperature-time converted master curve with 20 ° C as the reference temperature in RADII, and calculate the frequency f value of (a) and (b) from f (Hz) = ω / (2π) G 'was read.
[0012]
According to a second aspect of the present invention, in the first aspect of the present invention, the intermediate film has pressure-sensitive adhesive layer adhesive surfaces on both sides.
According to a third aspect of the present invention, in the first or second aspect of the present invention, a release film is attached to the adhesive surface of the intermediate film.
[0013]
When the pressure-sensitive adhesive layer is a single layer, release films are attached to both the front and back surfaces to form an intermediate film. In addition, in order to improve the handleability (workability) of the interlayer film, when pressure sensitive adhesive layers are formed on both sides with a highly rigid film or sheet as the core material, multiple pressure sensitive adhesive layers are formed. Is done.
[0014]
In the invention according to claim 4, in the invention according to any one of claims 1 to 3, the thickness of the pressure-sensitive adhesive layer having the viscoelastic properties (a) and (b) is 0. 0.05 to 2 mm.
[0015]
In the invention described in claim 5, claims 1 in the invention described in any one of claim 4, the reference temperature 20 ° C, the storage modulus G at the frequency 10 ^{^-7} Hz '(10 ^-7 Hz ) And the thickness t (mm) of the pressure-sensitive adhesive layer having the viscoelastic properties (a) and (b): G ′ (10 ⁻⁷ Hz) / t is 25 to 1 × 10 ⁵ is there.
[0016]
In the invention according to claim 6, in the invention according to any one of claims 1 to 5, the pressure-sensitive adhesive having the viscoelastic properties of (a) and (b) is an acrylic pressure-sensitive adhesive. It is an adhesive.
[0017]
Moreover, in order to achieve the second object, the laminated glass plate of the invention according to claim 7 is formed by using the interlayer film according to any one of claims 1 to 6, and between the glass plates. And at least two sheets of synthetic resin plates or synthetic resin plates.
[0018]
Therefore, in the invention described in claim 1, since the interlayer film is formed of a pressure-sensitive adhesive having a specific range of viscoelastic characteristics, the thickness of the glass plate and the pressure-sensitive adhesive layer itself after the processing is not increased. Flow (wetting) proceeds to fill the unevenness of the interface due to uniformity. However, the dimensional stability over time of the pressure sensitive adhesive layer is ensured.
[0019]
In the invention according to claim 2, in the invention according to claim 1, since the intermediate film has adhesive surfaces of the pressure-sensitive adhesive layer on both sides, the intermediate film can be used without using another pressure-sensitive adhesive. The alignment process can be performed at room temperature simply by using the intermediate film.
[0020]
In the invention according to claim 3, in the invention according to claim 1 or claim 2, since the release film is adhered to both the front and back adhesive surfaces, the intermediate film can be stored in an overlapping manner. The storage space for the membrane is small. In use, the adhesive surface is easily exposed by peeling the release film.
[0021]
In the invention according to claim 4, in the invention according to any one of claims 1 to 3, since the thickness of the pressure-sensitive adhesive layer is 0.05 to 2 mm, the surfaces of the glass plate and the interlayer film As a result, the adhesiveness to the glass plate can be ensured satisfactorily, and the amount of the pressure sensitive adhesive for forming the pressure sensitive adhesive layer is not excessive.
[0022]
In invention of Claim 5, in the invention as described in any one of Claims 1-4, a glass plate and the magnitude | size of the storage elastic modulus G '(10 ^<-7> Hz) of a pressure sensitive adhesive are used. Although the familiarity with the uneven portion on the surface of the intermediate film changes, the ratio between the storage elastic modulus G ′ (10 ⁻⁷ Hz) of the pressure-sensitive adhesive and the thickness t (mm) of the pressure-sensitive adhesive layer: G ′ Since (10 ⁻⁷ Hz) / t is 25 to 1 × 10 ⁵ , it becomes easy to become familiar.
[0023]
In the invention according to claim 6, since the pressure-sensitive adhesive is an acrylic pressure-sensitive adhesive in the invention according to any one of claims 1 to 1, weather resistance and transparency Will be better.
[0024]
A laminated glass plate according to a seventh aspect of the present invention is a method of joining glass plates, a glass plate and a synthetic resin plate or synthetic resin plates using the intermediate film according to any one of the first to sixth aspects. Therefore, it can be joined without using an autoclave.
[0025]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of the present invention will be described.
As shown in FIG. 1, the intermediate film 1 is composed of a pressure-sensitive adhesive layer 2 and a release film 3 attached to both the front and back adhesive surfaces. The pressure sensitive adhesive layer 2 is composed of a pressure sensitive adhesive having the following viscoelastic properties (a) and (b). (A) Storage elastic modulus G ′ (1 Hz) at a measurement temperature of 20 ° C. and a frequency of 1 Hz is 5 × 10 ^{3 to} 5 × 10 ⁵ Pa (pascal). (B) Storage elastic modulus G ′ (10 ⁻⁷ Hz) at a reference temperature of 20 ° C. and a frequency of 10 ⁻⁷ Hz is 5 × 10 ^{1 to} 5 × 10 ³ Pa.
[0026]
The pressure sensitive adhesive layer 2 preferably has a thickness t of 0.05 to 2 mm. If the thickness is less than 0.05 mm, the adhesion tends to be inferior, and if it exceeds 2 mm, there is a problem in cost. When the thickness is 0.05 to 2 mm, the glass plate, the synthetic resin plate, and the pressure-sensitive adhesive layer 2 are produced when the laminated glass is produced by joining the glass plates, the glass plate and the synthetic resin plate or the synthetic resin plates. Adhesiveness to the glass plate and the synthetic resin plate is reliably ensured corresponding to the unevenness of its own surface, and the amount of the pressure sensitive adhesive for forming the pressure sensitive adhesive layer 2 is not excessive.
[0027]
Ratio of storage elastic modulus G ′ (10 ⁻⁷ Hz) at a reference temperature of 20 ° C. and a frequency of 10 ⁻⁷ Hz of the pressure-sensitive adhesive to a thickness t (mm) of the pressure-sensitive adhesive layer 2: G ′ ( 10 ⁻⁷ Hz) / t is set to 25 to 1 × 10 ⁵ .
[0028]
The conventional interlayer film for laminated glass is a hot-melt type in which the unevenness of two glass plates is filled by heating and melting, whereas the interlayer film of the present invention has a viscoelastic property that can be bonded at room temperature. A pressure adhesive is used.
[0029]
The pressure-sensitive adhesive used for the interlayer film of the present invention moderates moderately by controlling the storage elastic modulus for a long period of time within a specific range. Therefore, the pressure-sensitive adhesive deformed during the mating process can be adjusted to the thickness unevenness after the mating and relaxed to obtain a mated appearance without bubbles.
[0030]
That is, it is important that the storage elastic modulus G ′ (10 ⁻⁷ Hz) at a frequency of 10 ⁻⁷ Hz is in the range of 5 × 10 ^{1 to} 5 × 10 ³ Pa. After glass processing combined excessively fluidized storage elastic modulus G '(10 ^-7 Hz) is less than 5 × 10 ¹ Pa, or protruding intermediate film, there is a problem that the glass plate or the like is deviated, a 5 × 10 ³ Pa When exceeding, there is a problem that bubbles are generated in the concave portion due to the unevenness of the slight thickness unevenness of the intermediate film after being processed into the laminated glass. Further, it is also important in normal temperature bonding processing that the storage elastic modulus G ′ (1 Hz) is in the range of 5 × 10 ^{3 to} 5 × 10 ⁵ Pa. That is, when the storage elastic modulus G ′ (1 Hz) is 5 × 10 ³ Pa or less, it is difficult to maintain the shape immediately after bonding, and when the storage elastic modulus G ′ (1 Hz) is 5 × 10 ⁵ Pa or more. In addition, the wettability with the glass plate or the synthetic resin plate is poor and sufficient adhesive force cannot be secured.
[0031]
The pressure-sensitive adhesive forming the pressure-sensitive adhesive layer 2 can be appropriately selected as long as it satisfies the viscoelastic properties, but it is preferable to use an acrylic pressure-sensitive adhesive having good weather resistance and transparency. As an acrylic pressure sensitive adhesive, there is an ionomer resin obtained by adding a metal compound or the like to a (meth) acrylic acid ester copolymer containing ethylene and an α, β unsaturated carboxylic acid to crosslink the metal ions. As the metal compound, an acetylacetone metal complex having a zinc ion, a sodium ion, or the like, a metal oxide, a fatty acid metal salt, or the like is used. As the ionomer resin, an ionically crosslinked resin may be used. However, an ionomer resin obtained by adding a metal compound to the copolymer during the production of the intermediate film is more preferable.
[0032]
Next, a method for producing a laminated glass using the intermediate film 1 will be described with reference to FIG. There are various methods for the joining process, but the following method is preferable because it can be joined without using an autoclave. In some cases, the laminated glass joins the glass plates, and the glass plate and the synthetic resin plate or the synthetic resin plates. In this embodiment, the glass plate and the synthetic resin plate are joined.
[0033]
As shown in FIG. 2 (a), first, the intermediate film 1 from which the release film 3 on one side is peeled off is applied to either the glass plate 4 or the synthetic resin plate 5 (in this embodiment, the glass plate 4). And between the drive rubber rolls 7 so as to be in contact with each other for the first time, and the intermediate film 1 is stuck on the surface of the glass plate 4. Next, the remaining release film 3 is peeled off, and as shown in FIG. 2 (b), the glass plate 4 with the intermediate film 1 attached is faced to the synthetic resin plate 5 through the intermediate film 1 without being brought into contact therewith, Laminated glass 8 is completed when both plates are continuously joined with the end portions of the two plates sandwiched between the nip roll 6 and the nip roll 6 and the drive rubber roll 7 so as to contact each other for the first time.
[0034]
In this method, the linear pressure of the nip roll 6 allows adhesion without interposing bubbles between the synthetic resin plate 5 and the intermediate film 1. In other words, since the distortion of the intermediate film 1 applied in a short time due to the linear pressure tries to recover, the synthetic resin plate 5 just before the nip roll that has not yet been bonded is slightly curved, and a gap is always generated between the two plates. The feeling can be pushed out. By utilizing the viscoelastic characteristics of the interlayer film 1 of the present invention, the conventional vacuum defoaming / temporary bonding and high-temperature / high-pressure treatment by an autoclave are not required, and it is possible to work at room temperature. The glass 8 is also excellent in quality without bubbles.
[0035]
Hereinafter, the present invention will be described in more detail with reference to examples and comparative examples.
Example 1
An acrylic pressure-sensitive adhesive sheet having a thickness of 1.0 mm in which an acrylic ester copolymer was cross-linked with a metal compound and a release film 3 was attached to both front and back surfaces was used as the intermediate film 1.
[0036]
The acrylic acid ester copolymer is obtained by copolymerizing n-butyl acrylate: 78.4% by weight, 2-ethylhexyl acrylate: 19.6% by weight and acrylic acid: 2.0% by weight. The molecular weight and molecular weight distribution measured by GPC of the copolymer were weight average molecular weight (MW): 2.27 × 10 ⁶ , weight average molecular weight (MW) / number average molecular weight (MN): 3.6.
[0037]
The acrylic pressure-sensitive adhesive sheet was prepared by melting and stirring acetylacetone zinc salt: 0.5 part by weight and acetylacetone aluminum salt: 0.7 part by weight as metal compounds with respect to 100 parts by weight of the acrylic ester copolymer. It was obtained by forming into a sheet shape with a predetermined thickness (1.0 mm) between the films.
[0038]
On one side of a commercially available float glass plate (thickness 3 mm, width 200 mm, length 300 mm), the intermediate film from which the release film on one side has been peeled is transferred between the nip roll and the drive rubber roll so as to be in contact for the first time The paper was stuck at a paper pressure of 1 kgf / cm and a speed of 5 m / min), and the remaining template film was peeled off.
[0039]
Next, the glass plate on which the intermediate film is pasted faces each other without contacting a commercially available polycarbonate plate (thickness 2 mm, width 200 mm, length 300 mm, UV cut, hard coat treatment) via the intermediate film. A laminated glass was obtained by sandwiching the end of the plate between the nip roll and the driving rubber roll so as to contact the nip roll (linear pressure: 20 kgf / cm, speed 0.5 m / min) for the first time.
[0040]
(Example 2)
A solution in which the uncrosslinked acrylate copolymer obtained in Example 1 was adjusted to a solid content of 40% by weight with ethyl acetate: 25 parts by weight of tolylene diisocyanate (TDI) as a crosslinking agent in ethyl acetate with respect to 100 parts by weight Solution adjusted to%: 2.0 parts by weight are mixed and stirred, applied to a release film to an arbitrary thickness, and after drying the solvent, a pressure-sensitive adhesive layer having a thickness of 1.0 mm is released. An intermediate film sandwiched between the films was obtained. Using this interlayer film, a laminated glass was produced under the same conditions as in Example 1.
[0041]
(Comparative Example 1)
A solution in which the uncrosslinked acrylate copolymer obtained in Example 1 was adjusted to a solid content of 40% by weight with ethyl acetate: 25 parts by weight of tolylene diisocyanate (TDI) as a crosslinking agent in ethyl acetate with respect to 100 parts by weight A solution adjusted to%: 9.0 parts by weight of the mixture was mixed and stirred, applied to a release film to an arbitrary thickness, dried after the solvent was overlaid, and a pressure-sensitive adhesive layer having a thickness of 1.0 mm was released. An intermediate film sandwiched between the films was obtained. Using this interlayer film, a laminated glass was produced under the same conditions as in Example 1.
[0042]
(Comparative Example 2)
The uncrosslinked acrylate copolymer obtained in Example 1 was formed into a sheet between release films to obtain an interlayer film having a thickness of 1.0 mm. The method for producing the laminated glass was performed under the same conditions as in Example 1.
[0043]
Next, the following items were evaluated using each laminated glass obtained in the examples and comparative examples. The results are shown in Table 1. Items with no problems are indicated by (○).
[0044]
[Immediately after the lamination]: The appearance immediately after the production of the laminated glass (the presence or absence of bubbles, peeling, plate displacement, protrusion of the intermediate film, etc.) was observed.
[1 day after lamination]: After the laminated glass was produced, the appearance (in the presence or absence of bubbles, peeling, deviation of the plate, protrusion of the intermediate film, etc.) after 40 ° C × 1 day was observed with the laminated glass inclined at 45 ° did.
Observed.
[0045]
[Table 1]

As is apparent from the results of Table 1, when the interlayer film of the present invention is used, a laminated glass that can be laminated at room temperature and can be satisfied in appearance can be obtained, while the viscoelastic characteristics of the present invention are It can be seen that any of the observation items cannot be satisfied with the laminated glass using the interlayer film composed of the pressure-sensitive adhesive that is outside the range of the storage elastic modulus measured by the frequency.
[0046]
This embodiment has the following effects.
(1) The intermediate film 1 is composed of a pressure-sensitive adhesive layer 2 and a release film 3, and the intermediate film has a structure in which the adhesive surfaces of the pressure-sensitive adhesive layer 2 exist on both front and back sides. By stripping and using, it is possible to align glass plates 4 and between glass plates 4 and synthetic resin plates 5 or synthetic resin plates 5 at room temperature without requiring high-temperature and high-pressure treatment by heat temporary bonding or autoclave. It becomes.
[0047]
(2) Since the long-term storage elastic modulus is in a specific range, the pressure-sensitive adhesive layer deformed during the laminating process is relaxed in conformity with the thickness unevenness after the laminating, and a bonded appearance without bubbles is obtained. it can.
[0048]
(3) Since the thickness of the pressure-sensitive adhesive layer 2 is 0.05 to 2 mm, the glass plate 4 and the synthetic resin plate 5 surely correspond to the irregularities on the surfaces of the glass plate 4, the synthetic resin plate 5 and the intermediate film 1. As a result, the amount of the pressure-sensitive adhesive for forming the pressure-sensitive adhesive layer 2 is not excessive.
[0049]
(4) The ease of fitting to the uneven portions on the surface of the glass plate 4, the synthetic resin plate 5 and the intermediate film 1 changes depending on the size of the storage elastic modulus G ′ (10 ⁻⁷ Hz) of the pressure-sensitive adhesive. Ratio of storage elastic modulus G ′ (10 ⁻⁷ Hz) of pressure adhesive and thickness t (mm) of pressure sensitive adhesive layer 2: G ′ (10 ⁻⁷ Hz) / t is 25 to 1 × 10 ⁵ Therefore, it becomes easy to become familiar.
[0050]
(5) Since the pressure sensitive adhesive is an acrylic pressure sensitive adhesive, weather resistance and transparency are improved.
(6) Because the intermediate film 1 has a structure in which the release film 3 is adhered to both the front and back adhesive surfaces, the first release film 3 is peeled off, and the glass film 4 and the synthetic resin plate 5 are first provided with good workability. Next, the other release film 3 can be peeled off and attached to the other of the glass plate 4 and the synthetic resin plate 5 with good workability. Moreover, it becomes easier to form the pressure-sensitive adhesive to a predetermined thickness as compared with the case where the pressure-sensitive adhesive layer 2 is formed by directly applying the pressure-sensitive adhesive to the glass plate 4 or the synthetic resin plate 5.
[0051]
The embodiment is not limited to the above, and may be embodied as follows, for example.
The intermediate film 1 is not limited to the pressure-sensitive adhesive layer 2, but for example, as shown in FIG. 3 (a), a net-like material formed of a film, a sheet, or a fiber is used as a core 9, and both sides thereof Alternatively, the pressure-sensitive adhesive layer 2 may be formed. In this case, when a highly biaxially stretched polyethylene terephthalate film or the like is used, the handleability (workability) of the intermediate film 1 is particularly improved. Further, when producing a laminated glass 8 having a configuration in which the glass plates 4 are bonded to both sides of the intermediate film 1, as shown in FIG. 3B, a plate material such as a polycarbonate plate or the like as the core material 9 of the intermediate film 1, or A film having a large elongation made of polyurethane, polyvinyl butyral, ethylene-vinyl acetate copolymer or the like may be used. In this case, the impact resistance and penetration resistance of the laminated glass 8 are improved. That is, in the present invention, the intermediate film 1 means a thin flat film having a certain degree of flexibility.
[0052]
○ At least one pressure-sensitive adhesive layer 2 having the viscoelastic property may be present, and as the structure of the intermediate film 1, for example, as shown in FIG. The adhesive layer 2 and the pressure-sensitive adhesive layer 10 or intermediate film other than the present invention laminated in two layers, the pressure-sensitive adhesive layer 2 and a planar reinforcing material 11 such as a plate, sheet, film, fiber, etc. May be laminated in two layers. Moreover, as shown in FIG.4 (c), it is good also as a structure by which the pressure sensitive adhesive layer 10 or intermediate films other than this invention were laminated | stacked on both sides on both sides of the pressure sensitive adhesive layer 2. As shown in FIG.
[0053]
When the surface of the pressure-sensitive adhesive layer 10 other than the pressure-sensitive adhesive layer 2 of the present invention (or a plate to be combined) has irregularities, the pressure-sensitive adhesive layer 10 other than the present invention alone is attached as in the comparative example. When the pressure-sensitive adhesive layer 2 of the present invention is present in one or more layers, as shown in FIG. 5, the unevenness of the pressure-sensitive adhesive layer 10 other than the present invention of the front and back layers as shown in FIG. 12 is relaxed in the inside, that is, the pressure-sensitive adhesive layer 2 of the present invention, and generation of bubbles is prevented.
[0054]
In the case where the pressure sensitive adhesive layer 2 or the pressure sensitive adhesive layer 10 is not provided on the outer surface of the intermediate film 1, the pressure sensitive adhesive is applied to the surface of the plate to be mated for mating at room temperature. Also, use an adhesive that requires heating but does not require high-temperature and high-pressure conditions that require an autoclave (for example, an adhesive such as a conventional ethylene- (meth) acrylate copolymer). Processing may be performed. In this case, even if bonding is performed by heat bonding, the presence of the pressure-sensitive adhesive layer 2 of the present invention absorbs a dimensional change due to a difference in linear expansion coefficient between the plates on both sides, and prevents warping and the like. it can.
[0055]
When the pressure-sensitive adhesive layer 2 and the other pressure-sensitive adhesive layer 10 of the present invention are laminated, the interface adhesive strength between the glass plate 4 or the synthetic resin plate 5 and the pressure-sensitive adhesive layer can be adjusted. That is, the pressure-sensitive adhesive layer 10 having a greater adhesive strength to the glass plate 4 or the synthetic resin plate 5 than the pressure-sensitive adhesive of the present invention ensures the adhesive strength to the glass plate 4 or the synthetic resin plate 5 and is deformed during the laminating process. The pressure-sensitive adhesive layer 2 of the present invention takes charge of stress relaxation, whereby an intermediate film having an appropriate adhesive force can be obtained.
[0056]
○ As a method of manufacturing the laminated glass 8 using the intermediate film 1, the pressure sensitive adhesive layer 2 is formed by attaching the intermediate film 1 to one of the glass plate 4 and the synthetic resin plate 5, and then the other glass plate 4 or the synthetic resin plate 5 is placed on the pressure-sensitive adhesive layer 2 and placed in the vacuum tank, and the pressure in the tank is reduced to reduce the pressure-sensitive adhesive layer 2 and the glass plate 4 or the synthetic resin plate 5. After the air layer remaining in between is discharged, it may be pressed and bonded.
[0057]
O The pressure sensitive adhesive which comprises the intermediate film 1 may be apply | coated directly on the surface of the glass plate 4 or the synthetic resin board 5, and the pressure sensitive adhesive layer 2 of predetermined thickness may be formed. However, it is easier to form the pressure-sensitive adhesive layer 2 having a predetermined thickness when it is formed in the form of a sheet sandwiched between the release films 3.
[0058]
○ The total number of glass plates and synthetic resin plates constituting the laminated glass is not limited to two, and may be three or more.
○ Instead of the PC plate, the synthetic resin plate 5 may be an acrylic plate, a hard polyvinyl chloride plate, a polyester plate, or the like.
[0059]
○ In addition, in the case of an intermediate film with a pressure sensitive adhesive layer on both the front and back sides, it can be processed by simply peeling off the surface release film without using any other pressure sensitive adhesive. . Therefore, the intermediate film having such a structure can be suitably used for applications that dislike heating between the surface protective glass of the solar cell and the silicon cell, filling material, and the like.
[0060]
The technical ideas (inventions) other than the claims that can be grasped from the embodiment will be described below together with the effects thereof.
(1) In the invention described in claim 2, the pressure-sensitive adhesive layer is formed on both surfaces of a film-like core material. In this case, the handleability (workability) of the intermediate film is improved.
[0061]
(2) In the invention according to claim 6, a polycarbonate plate is used for the synthetic resin plate. In this case, it is easy to obtain a plate having a small thickness and excellent impact resistance and heat resistance, which contributes to thinning of the laminated glass.
[0062]
【The invention's effect】
As described above in detail, according to the invention described in claims 1 to 7, the glass plates or the glass plates and the synthetic resin plates are used at room temperature without requiring high-temperature and high-pressure treatment by heat temporary bonding and autoclave. Can be combined.
[0063]
According to the second aspect of the present invention, the alignment process can be performed at room temperature only by using the intermediate film without using another pressure-sensitive adhesive. Moreover, it can use suitably for the use which dislikes the adhesion | attachment between the surface protection glass of a solar cell, and a silicon cell, heating of a filling material, etc.
[0064]
According to invention of Claim 3, when manufacturing a laminated glass, a pressure sensitive adhesive layer can be formed in the predetermined | prescribed thickness with sufficient workability | operativity on the surface of a glass plate or a synthetic resin board.
[0065]
According to the invention described in claim 4, the adhesiveness of the pressure-sensitive adhesive layer to the glass plate and the synthetic resin plate is ensured, and the amount of the pressure-sensitive adhesive for forming the pressure-sensitive adhesive layer. Is not excessive.
[0066]
According to invention of Claim 5, a pressure sensitive adhesive becomes easy to adjust to the uneven | corrugated | grooved part of the surface of a glass plate, a synthetic resin board, and an intermediate film.
According to the invention described in claim 6, weather resistance and transparency are improved.
[Brief description of the drawings]
FIG. 1 is a schematic cross-sectional view of an intermediate film.
FIG. 2 is a process schematic diagram showing an example of a method for producing a laminated glass.
3A is a schematic cross-sectional view of an intermediate film of another embodiment, and FIG. 3B is a schematic cross-sectional view of a laminated glass manufactured using the intermediate film of another embodiment.
FIG. 4 is a schematic cross-sectional view of an intermediate film according to another embodiment.
FIG. 5 is a schematic cross-sectional view illustrating the operation of an intermediate film according to another embodiment.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Intermediate film, 2 ... Pressure sensitive adhesive layer, 3 ... Release film, 4 ... Glass plate, 5 ... Synthetic resin plate, 8 ... Laminated glass.

Claims

After bonding the glass plate, in order to obtain the appearance have the name of the bubble, following (a) and a planar pressure sensitive adhesive layer formed with a pressure sensitive adhesive having a viscoelastic property of the (b) at least An interlayer film for laminated glass, wherein one layer is provided.
(A) Storage elastic modulus G ′ (1 Hz) at a measurement temperature of 20 ° C. and a frequency of 1 Hz is 5 × 10 ^{3 to} 5 × 10 ⁵ Pa (pascal).
(B) Storage elastic modulus G ′ (10 ⁻⁷ Hz) at a reference temperature of 20 ° C. and a frequency of 10 ⁻⁷ Hz is 5 × 10 ^{1 to} 5 × 10 ³ Pa.

The interlayer film for laminated glass according to claim 1, wherein the interlayer film has adhesive surfaces of pressure-sensitive adhesive layers on both sides.

The interlayer film for laminated glass according to claim 1 or 2, wherein a release film is attached to the adhesive surface of the interlayer film.

The interlayer film for laminated glass according to any one of claims 1 to 3, wherein a thickness of the pressure-sensitive adhesive layer having the viscoelastic properties (a) and (b) is 0.05 to 2 mm.

The storage elastic modulus G ′ (10 ⁻⁷ Hz) at a reference temperature of 20 ° C. and a frequency of 10 ⁻⁷ Hz, and the thickness t (mm) of the pressure-sensitive adhesive layer having the viscoelastic properties (a) and (b) above. ): G ′ (10 ⁻⁷ Hz) / t is 25 to 1 × 10 ^{5. The} interlayer film for laminated glass according to claim 1, wherein G ′ (10 ⁻⁷ Hz) / t is 25 to 1 × 10 ⁵ .

The interlayer film for laminated glass according to any one of claims 1 to 5, wherein the pressure-sensitive adhesive having viscoelastic properties (a) and (b) is an acrylic pressure-sensitive adhesive.

Laminated glass formed by bonding at least two glass plates, glass plates and synthetic resin plates or synthetic resin plates using the interlayer film according to any one of claims 1 to 6.