JP4297297B2 - Volume hologram laminate and label for producing volume hologram laminate - Google Patents

Description

【００３２】
（東亜合成化学工業（株）製、商品名、アロニックス Ｍ−３１５）
【００３３】
【化２】

【００３４】
（東亜合成化学工業 (株）製、商品名、アロニックス Ｍ−３２５）、また、２，２′−ビス（4-アクリロキシ・ジエトキシフェニル) プロパン（新中村化学 (株）製、商品名、ＮＫエステル A-BPE-4 ）、テトラメチロールメタンテトラアクリレート（新中村化学 (株）製、商品名、ＮＫエステル A-TMMT）等が挙げられる。
なお、本発明ではアクリル系モノマー、メタクリル系モノマーを（メタ）アクリル系モノマーと呼称する。
【００３５】
必要に応じて添加される可塑剤としては、エチレングリコール、ジエチレングリコール、トリエチレングリコール、テトラエチレングリコール、グリセリン、トリメチロールプロパン等の多価アルコール類、およびこれらの多価アルコールの末端ヒドロキシル基がエーテル化、アセチル化等によりブロックされた誘導体、重量平均分子量２００〜２，０００、好ましくは２００〜６００のポリエチレングリコール、重量平均分子量３００〜２，０００、好ましくは３００〜１０００のポリプロピレングリコール等のポリアルキレングリコール類、フタル酸ジメチル（ＤＭＰ）、フタル酸ジエチル（ＤＥＰ）、フタル酸ジブチル（ＤＢＰ）、フタル酸ヘプチルノニル（ＨＮＰ）、フタル酸ジ−２−エチルヘキシル（ＤＯＰ）、フタル酸ジ−ｎ−オクチル（ＤＮＯＰ）、フタル酸ジ−ｉ−オクチル（ＤＣａｐＰ）、フタル酸（７９アルキル）（Ｄ７９Ｐ）、フタル酸ジ−ｉ−デシル（ＤＩＤＰ）、フタル酸ジトリデシル（ＤＴＤＰ）、フタル酸ジシクロヘキシル（ＤＣＨＰ）、フタル酸ブチルベンジル（ＢＤＰ）、エチルフタリルエチルグリコレート（ＥＰＥＧ）、ブチルフタリルブチルグリコレート（ＢＰＢＧ）等のフタル酸エステル系可塑剤、アジピン酸−ジ−２−エチルヘキシル（ＤＯＡ）、アジピン酸−ジ−（メチルシクロヘキシル）、アジピン酸ジイソデシル（ＤＩＤＡ）、アゼライン酸−ジ−ｎ−ヘキシル（ＤＮＨＺ）、アゼライン酸−ジ−２−エチルヘキシル（ＤＯＺ）、セバシン酸ジブチル（ＤＢＳ）、セバシン酸ジ−２−エチルヘキシル（ＤＯＳ）等の脂肪族二塩基酸エステル系可塑剤、クエン酸トリエチル（ＴＥＣ）、クエン酸トリブチル（ＴＢＣ）、アセチルクエン酸トリエチル（ＡＴＥＣ）、アセチルクエン酸トリブチル（ＡＴＢＣ）等のクエン酸エステル系可塑剤、エポキシ化大豆油等のエポキシ系可塑剤、リン酸トリブチル（ＴＢＰ）、リン酸トリフェニル（ＴＰＰ）、リン酸トリクレジル（ＹＣＰ）、リン酸トリプロピレングリコール等のリン酸エステル系可塑剤等のポリエステル系可塑剤等が挙げられる。
【００３６】
次に、開始剤系における光重合開始剤としては、１，３−ジ（ｔ−ブチルジオキシカルボニル）ベンゾフェノン、３，３′，４，４′−テトラキス（ｔ−ブチルジオキシカルボニル）ベンゾフェノン、Ｎ−フェニルグリシン、２，４，６−トリス（トリクロロメチル）−ｓ−トリアジン、３−フェニル−５−イソオキサゾロン、２−メルカプトベンズイミダゾール、また、イミダゾール二量体類等が例示される。光重合開始剤は、記録されたホログラムの安定化の観点から、ホログラム記録後に分解処理されるのが好ましい。例えば有機過酸化物系にあっては紫外線照射することにより容易に分解されるので好ましい。
【００３７】
増感色素としては、３５０〜６００ｎｍに吸収光を有するチオピリリウム塩系色素、メロシアニン系色素、キノリン系色素、スチリルキノリン系色素、ケトクマリン系色素、チオキサンテン系色素、キサンテン系色素、オキソノール系色素、シアニン染料、ローダミン染料、チオピリリウム塩系色素、ピリリウムイオン系色素、ジフェニルヨードニウムイオン系色素等が例示される。なお、３５０ｎｍ以下、または６００ｎｍ以上の波長領域に吸収光を有する増感色素であってもよい。
【００３８】
マトリックス・ポリマーとしては、ポリメタアクリル酸エステル又はその部分加水分解物、ポリ酢酸ビニル又はその加水分解物、ポリビニルアルコールまたはその部分アセタール化物、トリアセチルセルロース、ポリイソプレン、ポリブタジエン、ポリクロロプレン、シリコーンゴム、ポリスチレン、ポリビニルブチラール、ポリクロロプレン、ポリ塩化ビニル、塩素化ポリエチレン、塩素化ポリプロピレン、ポリ−Ｎ−ビニルカルバゾール又はその誘導体、ポリ−Ｎ−ビニルピロリドン又はその誘導体、スチレンと無水マレイン酸の共重合体またはその半エステル、アクリル酸、アクリル酸エステル、メタクリル酸、メタクリル酸エステル、アクリルアミド、アクリルニトリル、エチレン、プロピレン、塩化ビニル、酢酸ビニル等の共重合可能なモノマー群の少なくとも１つを重合成分とする共重合体等、またはそれらの混合物が用いられる。好ましくはポリイソプレン、ポリブタジエン、ポリクロロプレン、ポリビニルアルコール、またポリビニルアルコールの部分アセタール化物であるポリビニルアセタール、ポリビニルブチラール、ポリ酢酸ビニル、エチレン−酢酸ビニル共重合体、塩化ビニル−酢酸ビニル共重合体等、またはそれらの混合物が挙げられる。
【００３９】
記録されたホログラムの安定化工程として加熱によるモノマー移動の工程があるが、そのためにはこれらのマトリックス・ポリマーは、好ましくはガラス転移温度が比較的低く、モノマー移動を容易にするものであることが必要である。
【００４０】
光重合可能な化合物は、バインダー樹脂１００重量部に対して１０重量部〜１０００重量部、好ましくは１０重量部〜１００重量部の割合で使用される。
【００４１】
光重合開始剤は、バインダー樹脂１００重量部に対して１重量部〜１０重量部、好ましくは５重量部〜１０重量部の割合で使用される。
【００４２】
増感色素は、バインダー樹脂１００重量部に対して０．０１重量部〜１重量部、好ましくは０．０１重量部〜０．５重量部の割合で使用される。
【００４３】
その他、感光性材料成分としては、各種の非イオン系界面活性剤、陽イオン系界面活性剤、陰イオン系界面活性剤が挙げられる。
【００４４】
これらのホログラム記録材料は、アセトン、メチルエチルケトン、メチルイソブチルケトン、シクロヘキサノン、ベンゼン、トルエン、キシレン、クロルベンゼン、テトラヒドロフラン、メチルセロソルブ、エチルセロソルブ、メチルセロソルブアセテート、エチルセロソルブアセテート、酢酸エチル、１，４−ジオキサン、１，２−ジクロロエタン、ジクロルメタン、クロロホルム、メタノール、エタノール、イソプロパノール等、またはそれらの混合溶剤を使用し、固型分１５％〜２５％の塗布液とされる。ホログラム記録層の乾燥後膜厚としては、０．１μｍ〜５０μｍ、好ましくは５μｍ〜２０μｍである。
このような、ホログラム記録材料としては、例えばデュポン社製のオムニデックス３５２、７０６が挙げられる。
【００４５】
次に、粘着剤層３、４について説明する。粘着剤層としては、アクリル樹脂、アクリル酸エステル樹脂、またはこれらの共重合体が挙げられる。また、粘着剤層が、使用時にイソシアネート系架橋剤、金属キレート系架橋剤等を添加して架橋する、所謂二液架橋型粘着剤を使用して形成されることもできる。粘着剤層の厚みとしては、４μｍ〜２０μｍとするとよい。
【００４６】
本発明の体積ホログラム積層体は、粘着剤層３、４の少なくとも一方に（メタ）アクリル系モノマーを添加することを特徴とする。（メタ）アクリル系モノマーとしては、分子量が１００〜５，０００の低分子量成分であり、特に分子量が１００〜２，０００のものを使用するとよい。分子量が１００より小さいと揮発性となり好ましくなく、また、５，０００を越えると隣接層への移動性が少なくなり、添加の目的を達しない可能性がある。
【００４７】
（メタ）アクリル系モノマーとしては、体積ホログラム層の項で記載したアクリル系モノマー、メタクリル系モノマーが挙げられるが、好ましくは、メトキシポリエチレングリコールメタクリレート（重量平均分子量４００）、メトキシジエチレングリコール（メタ）アクリレート、ポリエチレングリコールジ（メタ）アクリレート（重量平均分子量２００）、トリメチロールプロパントリ（メタ）アクリレート等が例示される。
【００４８】
（メタ）アクリル系モノマーは、体積ホログラム層を構成する成分と相溶性を有する物質を選択するのが好ましい。また、体積ホログラム層中に移行して記録された干渉縞を完全に破壊したり、また、記録再生を不能としないものであることが要求される。
【００４９】
（メタ）アクリル系モノマーは、上記の粘着剤と共に有機溶剤中に溶解・分散され、例えば剥離紙上に塗布乾燥されて粘着剤層とされるが、粘着剤層中に２重量％〜２０重量％、好ましくは５重量％〜１５重量％であり、２０重量％を越えると粘着性を阻害するので好ましくない。
【００５０】
本発明にあっては、（メタ）アクリル系モノマーが添加された粘着剤層が体積ホログラム層に積層されると、その詳細な理由は不明であるが、（メタ）アクリル系モノマーがホログラム記録された体積ホログラム層に移行し、体積ホログラム層を膨潤させる機能を有し、得られる再生波長を記録波長より長波長側にシフトさせることができるので、照明光源の輝線等の所望の再生波長に制御することを可能とする。
【００５１】
粘着剤層における記録波長シフト物質の含有量と、体積ホログラム層における再生波長との関係については、以下のような実験的手法により定めるとよい。
【００５２】
（波長シフト量の、光重合可能な化合物添加量依存性）
ホログラム記録フイルム：ＰＥＴフイルム／体積ホログラム層／ポリ塩化ビニルフイルム（デュポン社製「 Omnidex 706 」）
粘着フイルム：下記組成
・アクリル系粘着剤（日本カーバイド社製「ニッセツＰＥ−１１８」）
・・・１００重量部
・メチルエチルケトン ・・・ ３０重量部
・トルエン ・・・ １５重量部
・酢酸エチル ・・・ １５重量部
に対して、トリメチロールプロパントリアクリレート（ＴＭＰＴＡ）の添加量を相違させて添加して種々のＴＭＰＴＡ濃度の粘着剤を調製し、ＰＥＴフイルムに乾燥膜厚で１５μｍ塗布し、それぞれ粘着フイルムを作製する。
【００５３】
まず、ホログラム記録フイルムに４８８ｎｍの特定波長のアルゴンレーザーでホログラム記録した後、そのポリ塩化ビニルフイルムを剥離し、ホログラム面に粘着フイルムを粘着剤層側から貼着する。
【００５４】
得られたＰＥＴフイルム／体積ホログラム層／粘着剤層／ＰＥＴフイルムについて、実際の加工プロセスにおける条件である１４０℃で１５分間ベイクした後、島津製作所製「ＵＶ−２１００ＰＣ」を使用して、分光透過率を測定し、そのピーク波長を測定し、記録波長４８８ｎｍからのシフト量（ピーク波長−４８８ｎｍ＝Δλ）を計算する。
【００５５】
その測定結果を図３に示す。なお、図３には、ＴＭＰＴＡ濃度の単位は、１０^-4モルであり、アクリル系粘着剤１ｇ当たりの添加量である。図３に示すように、粘着剤層にＴＭＰＴＡの添加量０のものは、Δλはマイナスであり、体積ホログラム層から粘着剤層へ未反応モノマーや可塑剤等が移動し、体積ホログラム層が収縮し短波長側へ再生波長がシフトしたことがわかる。また、ＴＭＰＴＡの添加量が増大するとΔλが大となり、再生波長が長波長側にシフトする。
【００５６】
また、本発明にあっては、（メタ）アクリル系モノマーが添加された粘着剤層が体積ホログラム層に積層されると、その詳細な理由は不明であるが、その再生波長の制御を可能とすると同時に、その再生波長バンドを広げる作用があることを見出した。すなわち、本発明の体積ホログラム積層体は、照明光源の輝線がシャープな波長を有しているとしてもそれに対応させることができ、明るいホログラムを安定して得ることができる。
【００５７】
また、本発明の体積ホログラム積層体にあっては、第１粘着剤層および／または第２粘着剤層中に添加される移動成分の含有量を、体積ホログラム層における含有量とバランスさせ、両粘着剤層と体積ホログラム層との間で（メタ）アクリル系モノマー以外の移動成分の移動を生じないものとしておくと、より再生波長を安定したものとできる。
【００５８】
これらの移動成分としては、体積ホログラム層の構成材料として記載した光重合可能な化合物や可塑剤等が挙げられるが、これらの移動成分は体積ホログラム層の構成成分と同一でも相違していてもよいが、移動成分として（メタ）アクリル系モノマーを選択する場合には、上述した本発明における添加成分である（メタ）アクリル系モノマーの添加量を勘案して添加されるとよい。
【００５９】
また、移動成分としては、粘着付与剤（タッキファイヤー）、界面活性剤、ポリアルキレングリコール等も挙げられる。これらの移動成分は、分子量が１００〜５，０００の低分子量成分であり、特に分子量が１００〜２，０００のものを使用するとよい。分子量が１００より小さいと揮発性となり好ましくなく、また、５，０００を越えると隣接層への移動性が少なくなり、添加の目的を達しない可能性がある。また、粘着剤層に含有させる移動成分は、体積ホログラム層を構成する成分と相溶性を有する物質を選択するのが好ましく、また、体積ホログラム層中に移行して記録された干渉縞を完全に破壊したり、また、記録再生を不能としないものであることが要求される。
【００６０】
また、粘着剤層に含有させる移動成分は、粘着剤層中に上記した添加成分である（メタ）アクリル系モノマーと合わせその粘着性を損なわない程度に含有されるとよく、合計量が２０重量％以下とされるとよいが、その含有量は、体積ホログラム層における移動成分の含有量との関係、また、所望する再生波長との関係から適宜設定されるとよい。
【００６１】
次に、表面保護フイルム６は、透明性を有し、ポリエチレンフイルム、ポリプロピレンフイルム、ポリ弗化エチレン系フイルム、ポリ弗化ビニリデンフイルム、ポリ塩化ビニルフイルム、ポリ塩化ビニリデンフイルム、エチレン−ビニルアルコールフイルム、ポリビニルアルコールフイルム、ポリメチルメタクリレートフイルム、ポリエーテルスルホンフイルム、ポリエーテルエーテルケトンフイルム、ポリアミドフイルム、テトラフルオロエチレン−パーフルオロアルキルビニルエーテル共重合フイルム、ポリエチレンテレフタレートフイルム等のポリエステルフイルム、ポリイミドフイルム等の樹脂が例示され、膜厚としては２μｍ〜２００μｍ、好ましくは１０μｍ〜５０μｍである。
【００６２】
体積ホログラム積層体において体積ホログラム層が粘着性を有する場合、基材上に、粘着剤層、体積ホログラム層、表面保護フイルムとする場合がある。表面保護フイルムには、一般に、可塑剤が含有されており、この場合においても、粘着剤層、体積ホログラム層、表面保護フイルムの各層間で移動成分を勘案しそのバランスを調整するとよい。
【００６３】
なお、図示はしないが、表面保護フイルム上には、表面保護フイルム表面の保護性を高める目的で、必要に応じてハードコート処理が施されてもよい。ハードコート処理は、例えばシリコーン系、含フッ素シリコーン系、メラミンアルキッド系、ウレタン−アクリレート系（紫外線硬化型）等をディッピング塗布、スプレー塗布、ロールコート塗布法により、膜厚１μｍ〜５０μｍ、好ましくは３μｍ〜２５μｍに塗布するとよい。
【００６４】
更に、同様に、図示しないが、表面保護フイルム６表面又はハードコート処理面には、離型処理が施されていてもよい。離型処理は、フッ素系離型剤、シリコーン系離型剤、ステアリン酸塩系離型剤、ワックス系離型剤等をディッピング塗布、スプレー塗布、ロールコート塗布法により行なうとよい。
【００６５】
本発明の体積ホログラム積層体における体積ホログラム層は、記録波長としては単一波長でホログラム記録してもよく、また、二種以上の波長でカラーホログラム記録されてもよい。また、（メタ）アクリル系モノマーを粘着剤層に添加することにより、記録波長に対して再生波長をシフトさせることができる。
【００６６】
単一波長でホログラム記録する場合には、得られる再生波長域の半値幅を３０ｎｍ以上、好ましくは３５ｎｍ以上のものとでき、また、二種以上の波長でカラーホログラム記録する場合には、得られる各再生波長域の半値幅を２０ｎｍ以上、好ましくは２５ｎｍ以上のものとできる。
【００６７】
本発明の体積ホログラム積層体は、その再生波長を照明光源の輝線波長に合わせ込み、制御をすることが可能であると共に、再生バンドを広域化できるので、照明光源下で明るいホログラム像を再生することができる。
【００６８】
次に、本発明の体積ホログラム積層体作製用ラベルについて、その断面の層構成を図２に示す。図中、１０は体積ホログラム積層体作製用ラベル、１１は剥離紙であり、図１と同一符号は同一内容を示す。
【００６９】
本発明の体積ホログラム積層体作製用ラベルは、上述した体積ホログラム積層体の作製に使用されるものであり、図２に示す如く、剥離紙１１上に第１粘着剤層３、体積ホログラム層５、第２粘着剤層４、表面保護フイルム６を積層したものである。
【００７０】
剥離紙１１としては、通常使用される剥離紙の他に、ポリエチレンテレフタレートフイルム表面をフッ素系離型剤、シリコーン系離型剤により離型処理した離型性フィルムを使用してもよく、また、剥離紙の粘着剤層側でない面には、ラベルの横からはみ出した粘着剤によるブロッキングを避けるために剥離処理を施しておくとよい。また、積層体を適宜の大きさで剥離紙から剥離できるように、積層体は所謂「半抜き加工」されていてもよく、また、剥離紙にミシン目等の切れ目を入れておいてもよい。
【００７１】
ラベル１０は、剥離紙１１を剥離した後、第１粘着剤層３側から、基材上に積層され、図１に示される体積ホログラム積層体が作製される。
【００７２】
【実施例】
以下、本発明を実施例により説明する。
（実施例１）
（透明保護フイルム／第２粘着剤層／シリコンセパレータの作製）
シリコンセパレータ（東京セロファン（株）製「ＳＰ−ＰＥＴ０５」膜厚５０μｍ）上に、下記組成
・アクリル系粘着剤（日本カーバイド社製「ニッセツＰＥ−１１８」）
・・・１００重量部
・メチルエチルケトン ・・・ ３０重量部
・トルエン ・・・ １５重量部
・酢酸エチル ・・・ １５重量部
・イソシアネート系架橋剤（日本カーバイド社製「ニッセツＣＫ−１０１」）
・・・ １６重量部
の粘着剤溶液を、直ちに乾燥後膜厚１５μｍとなるようにコンマコーターで塗布した。これにポリエチレンテレフタレートフイルム（東レ（株）製「ルミラーＴ−６０、膜厚５０μｍ）をラミネートした。
【００７３】
（シリコンセパレータＡ／第１粘着剤層／シリコンセパレータＢの作製）
シリコンセパレータＡ（東京セロファン（株）製「ＳＰ−ＰＥＴ０５」膜厚５０μｍ）上に、下記組成
・アクリル系粘着剤（日本カーバイド社製「ニッセツＰＥ−１１８」）
・・・１００重量部
・メチルエチルケトン ・・・ ３０重量部
・トルエン ・・・ １５重量部
・酢酸エチル ・・・ １５重量部
・メトキシポリエチレングリコールメタクリレート（重量平均分子量４００、新中村化学工業（株）製） ・・・ １０重量部
の粘着剤溶液を、直ちに乾燥後膜厚１５μｍとなるようにコンマコーターで塗布した。これにシリコンセパレータＢ（東京セロファン（株）製「ＳＰ−ＰＥＴ０２」膜厚５０μｍ）をラミネートした。
【００７４】
（ホログラム記録フイルムの作製）
ポリエチレンテレフタレートフイルム（ＰＥＴフィルム：５０μｍ）／ホログラム記録材料／ポリ塩化ビニルフィルムの積層体からなるホログラム記録フイルム（オムニデックス７０６；デュポン社製）にリップマンホログラムを４８８ｎｍアルゴンレーザーで記録した。
【００７５】
（ホログラム積層体の作製）
上記で得たホログラム記録フイルムのポリ塩化ビニルフイルムを剥離し、また、上記で得たシリコンセパレータＡ／第１粘着剤層／シリコンセパレータＢからシリコンセパレータＡを剥離して、両者をラミネートし、ＰＥＴフイルム／体積ホログラム層／第１粘着剤層／シリコンセパレータＢを得た。
【００７６】
この積層体からＰＥＴフイルムを剥離し、また、上記で得た透明保護フイルム／第２粘着剤層／シリコンセパレータのシリコンセパレータを剥離して両者をラミネートし、透明保護フイルム／第２粘着剤層／ホログラム記録材料／第１粘着剤層／シリコンセパレータＢからなる本発明の体積ホログラム積層体ラベルを得た。
【００７７】
このラベルを１４０℃で１５分加熱し、分光特性を評価したところ、その再生波長は４９８ｎｍであり、記録波長とのΔλは＋１０ｎｍであり、また、半値幅は４３ｎｍであった。
【００７８】
（比較例）
実施例１における第１粘着剤層形成材料において、メトキシポリエチレングリコールメタクリレートを除いた他は同様にして体積ホログラム積層体作製用ラベルを作製し、同様に、その分光特性を評価したところ、その再生波長は４７２ｎｍであり、また、半値幅は２６ｎｍであった。
【００７９】
（実施例２）
実施例１における、ホログラム記録フイルムにかえて、ＰＥＴフィルム／ホログラム記録材料／ＰＥＴフィルムからなるホログラム記録フイルム（ＨＲＦ８００ｘ００１；デュポン社製）に、４７６ｎｍ、５３２ｎｍ、６４７ｎｍのそれぞれの波長を持ったレーザーを使用して、カラーリップマンホログラムを記録した。
【００８０】
得られたホログラム記録フイルムを使用して、実施例１同様に、透明保護フイルム／第２粘着剤層／ホログラム記録材料／第１粘着剤層／シリコンセパレータＢからなる本発明の体積ホログラム積層体ラベルを得た。
【００８１】
このラベルを１４０℃で１５分加熱し、分光特性を評価したところ、その再生波長は、それぞれ、４８７ｎｍ、５４４ｎｍ、６５５ｎｍとなり、記録波長とのΔλは＋１２ｎｍ、＋１２ｎｍ、＋８ｎｍであり、また、半値幅はそれぞれ、２１ｎｍ、２３ｎｍ、２７ｎｍとなった。
【００８２】
【発明の効果】
本発明の体積ホログラム積層体及び体積ホログラム積層体作製用ラベルは、所望の再生波長に制御することが可能であると共に、再生バンドを広域化できるので、照明光源下で明るいホログラム像を再生することができる。
【図面の簡単な説明】
【図１】 本発明の体積ホログラム積層体をその断面図で説明するための図である。
【図２】 本発明の体積ホログラム積層体作製用ラベルをその断面図で説明するための図である。
【図３】 粘着剤層におけるトリメチロールプロパントリアクリレート添加量と得られた体積ホログラム層における記録波長からの波長シフト量との関係を説明するための図である。
【符号の説明】
１は体積ホログラム積層体、２は基材、３は第１粘着剤層、４は第２粘着剤層、５は体積ホログラム層、６は表面保護フイルム、１０は体積ホログラム積層体作製用ラベル、１１は剥離シートである。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a volume hologram laminate and a label for producing a volume hologram laminate capable of widening the reproduction band of diffracted light, and a volume suitable as a color filter in a monochromatic or full color hologram or liquid crystal optical element. The present invention relates to a hologram laminate and a volume hologram laminate production label.
[0002]
[Prior art]
Conventionally, a volume hologram laminate generally has a configuration in which an adhesive layer, a volume hologram layer, an adhesive layer, and a transparent protective film are laminated in this order on a substrate, and the volume hologram is formed on an identification card or the like as a substrate. Although it is being used for recording a face image on a layer or as a color filter in a liquid crystal optical element, when reproducing a hologram recorded on a volume hologram layer, if the reproduction band of diffracted light is narrow, There is a problem that the illumination light source to be used is limited, and as a countermeasure to such a problem, the reproduction band of the diffracted light is widened by providing a tuning film or the like adjacent to the volume hologram layer. However, there is a problem that the film thickness of the volume hologram laminate is increased.
[0003]
[Problems to be solved by the invention]
It is an object of the present invention to provide a volume hologram laminate and a label for producing a volume hologram laminate that can broaden the reproduction band of diffracted light and obtain a bright hologram.
[0004]
[Means for Solving the Problems]
The volume hologram laminate of the present invention is a volume hologram laminate in which a first pressure-sensitive adhesive layer, a volume hologram layer, a second pressure-sensitive adhesive layer, and a surface protective film are sequentially laminated on a substrate. The second pressure-sensitive adhesive layer is an acrylic pressure-sensitive adhesive layer made of an acrylic resin, an acrylic ester resin, or a copolymer thereof, and (meth) acrylic monomer is contained in the layer in an amount of 2% by weight to 20% by weight. is, Rutotomoni is assumed that adhesive in the adhesive layer is not inhibited, the volume hologram layer is a hologram recording in a single-wavelength light, and wherein the half-value width of the reproduction wavelength region is 30nm or more.
[0005]
The volume hologram laminate of the present invention is a volume hologram laminate in which a first pressure-sensitive adhesive layer, a volume hologram layer, a second pressure-sensitive adhesive layer, and a surface protective film are sequentially laminated on a substrate. / Or the second pressure-sensitive adhesive layer is an acrylic pressure-sensitive adhesive layer made of an acrylic resin, an acrylate resin, or a copolymer thereof, and the (meth) acrylic monomer is 2 wt% to 20 wt% in the layer. % is contained, is intended to tack in the adhesive layer is not inhibited Rutotomoni, volume hologram layer is a color hologram recording at two or more wavelengths light, that their half-width of the reproduction wavelength range is 20nm or more It is characterized by.
[0006]
The pressure-sensitive adhesive layer is a two-component cross-linking pressure-sensitive adhesive that is cross-linked by adding a cross-linking agent during use.
[0007]
The volume hologram layer is made of a photopolymerizable compound and is hologram-recorded.
[0008]
The volume hologram laminate production label of the present invention is a volume hologram laminate production label in which a first pressure-sensitive adhesive layer, a volume hologram layer, a second pressure-sensitive adhesive layer, and a surface protective film are sequentially laminated on a release sheet. The first and / or second pressure-sensitive adhesive layer is an acrylic pressure-sensitive adhesive layer made of an acrylic resin, an acrylate resin, or a copolymer thereof, and (meth) acrylic monomer is 2 wt% in the layer. % to 20 wt% are contained, Rutotomoni is assumed that adhesive is not inhibited in the adhesive layer, the half-value width of the reproduction wavelength band of the hologram recorded in the volume hologram layer is characterized in that at 30nm or more.
[0009]
The volume hologram laminate production label of the present invention is a volume hologram laminate production label in which a first pressure-sensitive adhesive layer, a volume hologram layer, a second pressure-sensitive adhesive layer, and a surface protective film are sequentially laminated on a release sheet. The first and / or second pressure-sensitive adhesive layer is an acrylic pressure-sensitive adhesive layer made of an acrylic resin, an acrylic ester resin, or a copolymer thereof, and a (meth) acrylic monomer is contained in the layer. 2 wt% to 20 wt% is contained, is not intended to be inhibited sticky in the adhesive layer Rutotomoni are color hologram recorded in the volume hologram layer is two or more wavelength light, their half-width of the reproduction wavelength region Is 20 nm or more.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
The volume hologram laminate of the present invention is shown in a sectional view in FIG. In the figure, 1 is a volume hologram laminate, 2 is a substrate, 3 is a first pressure-sensitive adhesive layer, 4 is a second pressure-sensitive adhesive layer, 5 is a volume hologram layer, and 6 is a surface protective film.
[0011]
As the substrate 2 in the volume hologram laminate of the present invention, a film or sheet made of paper, synthetic paper, synthetic resin or metal can be used, such as a sheet shape such as an examination card, a card shape such as an ID card, It can take various forms such as a booklet such as a passport, and is used as a base material on which a volume hologram body in which a face photograph, landscape, etc. are recorded in a single color or full color is recorded. Moreover, when setting it as the color filter of a liquid crystal display element, the glass substrate and electrode layer in a liquid crystal cell become a base material.
[0012]
Further, in FIG. 1, the volume hologram laminate of the present invention shows a configuration in which a volume hologram layer 5 is laminated on a substrate 2 via a first pressure-sensitive adhesive layer 3. It is good also as a structure which laminated | stacked the layer 5 through the double-sided adhesive tape.
[0013]
The volume hologram layer 5 is a film in which an interference fringe corresponding to the wavefront of light from an object is recorded in the layer in the form of transmittance modulation and refractive index modulation after coating a volume hologram recording material on a support film. It may be a color hologram that reproduces two or more colors, or it may be a monochromatic hologram, and it can be easily produced by replicating and exposing and developing a volume hologram original plate for duplication. is there.
[0014]
The volume hologram layer 5 is a photosensitive material for use in dry volume phase hologram recording comprising a matrix polymer, a photopolymerizable compound, a photopolymerization initiator, a sensitizing dye, a plasticizer added as necessary, and a surfactant. Material.
[0015]
Examples of the photopolymerizable compound include photopolymerization having at least one ethylenically unsaturated bond in one molecule as described later, photocrosslinkable monomers, oligomers, prepolymers, and mixtures thereof. Examples thereof include unsaturated carboxylic acids and salts thereof, esters of unsaturated carboxylic acids and aliphatic polyhydric alcohol compounds, and amide bonds of unsaturated carboxylic acids and aliphatic polyvalent amine compounds.
[0016]
Specific examples of unsaturated carboxylic acid monomers include acrylic acid, methacrylic acid, itaconic acid, crotonic acid, isocrotonic acid, maleic acid, and their halogen-substituted unsaturated carboxylic acids such as chlorinated unsaturated carboxylic acids, brominated Examples thereof include unsaturated carboxylic acids and fluorinated unsaturated carboxylic acids. Examples of unsaturated carboxylic acid salts include sodium and potassium salts of the aforementioned acids.
[0017]
Specific examples of the monomer of an ester of an aliphatic polyhydric alcohol compound and an unsaturated carboxylic acid include acrylic acid esters such as ethylene glycol diacrylate, triethylene glycol diacrylate, 1,3-butanediol diacrylate, tetra Methylene glycol diacrylate, propylene glycol diacrylate, neopentyl glycol diacrylate, trimethylolpropane triacrylate, trimethylolpropane tri (acryloyloxypropyl) ether, trimethylolethane triacrylate, hexanediol diacrylate, 1,4-cyclohexanediol Diacrylate, tetraethylene glycol diacrylate, pentaerythritol diacrylate, pentaerythritol triac Rate, pentaerythritol tetraacrylate, dipentaerythritol diacrylate, dipentaerythritol triacrylate, dipentaerythritol tetraacrylate, dipentaerythritol hexaacrylate, sorbitol triacrylate, sorbitol tetraacrylate, sorbitol pentaacrylate, sorbitol hexaacrylate, tri (acryloyl) Oxyethyl) isocyanurate, polyester acrylate oligomer, 2-phenoxyethyl acrylate, 2-phenoxyethyl methacrylate, phenol ethoxylate monoacrylate, 2- (p-chlorophenoxy) ethyl acrylate, p-chlorophenyl acrylate, phenyl acrylate, 2-phenyl Ethyl acrylate , (2-acryloxy ethyl) ether of bisphenol A, ethoxylated bisphenol A diacrylate, 2- (1-naphthyloxy) ethyl acrylate, o- biphenyl methacrylate, and the like o- biphenyl acrylate.
[0018]
Methacrylic acid esters include tetramethylene glycol dimethacrylate, triethylene glycol dimethacrylate, neopentyl glycol dimethacrylate, trimethylolpropane trimethacrylate, trimethylolethane trimethacrylate, ethylene glycol dimethacrylate, 1,3-butanediol dimethacrylate, Hexanediol dimethacrylate, pentaerythritol dimethacrylate, pentaerythritol trimethacrylate, pentaerythritol tetramethacrylate, dipentaerythritol dimethacrylate, dipentaerythritol hexamethacrylate, sorbitol trimethacrylate, sorbitol tetramethacrylate, bis- [p- (3-methacryloxy 2-hydroxyp Epoxy) phenyl] dimethyl methane, bis - [p- (acryloxy ethoxy phenyl] dimethyl methane, 2,2-bis (4-methacryloyloxy) propane, there is methacrylic acid-2-naphthyl and the like.
[0019]
Itaconic acid esters include ethylene glycol diitaconate, propylene glycol diitaconate, 1,3-butanediol diitaconate, 1,4-butanediol diitaconate, tetramethylene glycol diitaconate, pentaerythritol diitaconate, Examples include sorbitol tetritaconate.
[0020]
Examples of crotonic acid esters include ethylene glycol dicrotonate, tetramethylene glycol dicrotonate, pentaerythritol dicrotonate, and sorbitol tetracrotonate.
[0021]
Examples of isocrotonic acid esters include ethylene glycol diisocrotonate, pentaerythritol diisocrotonate, and sorbitol tetraisocrotonate.
[0022]
Examples of maleic acid esters include ethylene glycol dimaleate, triethylene glycol dimaleate, pentaerythritol dimaleate, and sorbitol tetramaleate.
[0023]
Examples of the halogenated unsaturated carboxylic acid include 2,2,3,3-tetrafluoropropyl acrylate, 1H, 1H, 2H, 2H-heptadecafluorodecyl acrylate, 2,2,3,3-tetrafluoropropyl methacrylate, 1H , 1H, 2H, 2H-heptadecafluorodecyl methacrylate, -2,4,6-tribromophenyl methacrylate, dibromoneopentyl dimethacrylate (trade name: NK ester DBN, manufactured by Shin-Nakamura Chemical Co., Ltd.), dibromo Propyl acrylate (trade name: NK ester A-DBP, manufactured by Shin-Nakamura Chemical Co., Ltd.), dipromopropyl methacrylate (trade name: NK ester DBP, manufactured by Shin-Nakamura Chemical Co., Ltd.), methacrylic acid chloride, methacrylic acid -2,4,6-trichlorophenyl, p-chlorostyrene , Methyl 2-chloro acrylate, ethyl-2-chloro acrylate, n- butyl-2-chloro acrylate, tribromophenol acrylate, tetrabromo phenol acrylate.
[0024]
Specific examples of amide monomers of unsaturated carboxylic acids and aliphatic polyvalent amine compounds include methylene bisacrylamide, methylene bismethacrylamide, 1,6-hexamethylene bisacrylamide, and 1,6-hexamethylene bismethacrylamide. , Diethylenetriamine trisacrylamide, xylylene bisacrylamide, xylylene bismethacrylamide, N-phenylmethacrylamide, diacetone acrylamide and the like.
[0025]
Other examples include polyisocyanate compounds having two or more isocyanate groups in one molecule described in JP-B-48-41708, and the following general formula
CH ₂ = C (R) COOCH ₂ CH (R ′) OH
(Wherein R and R ′ represent hydrogen or a methyl group.)
And vinyl urethane compounds containing two or more polymerizable vinyl groups in one molecule to which a vinyl monomer containing a hydroxyl group represented by the formula (1) is added.
[0026]
Also, urethane acrylates described in JP-A-51-37193, JP-A-48-64183, JP-B-49-43191, JP-B-52-30490, respectively. Polyfunctional acrylates and methacrylates such as polyester acrylates, epoxy resins and (meth) acrylic acid can be mentioned.
[0027]
Furthermore, the Japan Adhesion Association Vol. No. 20, No. 7, pages 300 to 308, those introduced as photocurable monomers and oligomers can also be used.
[0028]
In addition, as a monomer containing phosphorus, mono (2-acryloyloxyethyl) acid phosphate (trade name: Light Ester PA, manufactured by Kyoeisha Yushi Chemical Co., Ltd.), mono (2-methacryloyl ethyl) acid phosphate (Product name: Light Ester PM, manufactured by Kyoeisha Yushi Chemical Co., Ltd.), and product name: Lipoxy VR-60 (manufactured by Showa Polymer Co., Ltd.), product name: Lipoxy VR- 90 (manufactured by Showa Polymer Co., Ltd.) and the like.
[0029]
Moreover, brand name: NK ester M-230G (made by Shin-Nakamura Chemical Co., Ltd.) and brand name: NK ester 23G (made by Shin-Nakamura Chemical Co., Ltd.) are also mentioned.
[0030]
Furthermore, triacrylates having the following structural formula:
[0031]
[Chemical 1]

[0032]
(Product name, Aronix M-315, manufactured by Toa Gosei Chemical Co., Ltd.)
[0033]
[Chemical formula 2]

[0034]
(Trade name, Aronix M-325, manufactured by Toa Gosei Chemical Industry Co., Ltd.), and 2,2'-bis (4-acryloxy-diethoxyphenyl) propane (trade name, NK manufactured by Shin-Nakamura Chemical Co., Ltd.) Ester A-BPE-4), tetramethylolmethane tetraacrylate (manufactured by Shin-Nakamura Chemical Co., Ltd., trade name, NK ester A-TMMT) and the like.
In the present invention, acrylic monomers and methacrylic monomers are referred to as (meth) acrylic monomers.
[0035]
As plasticizers added as necessary, polyhydric alcohols such as ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, glycerin and trimethylolpropane, and the terminal hydroxyl groups of these polyhydric alcohols are etherified. , Derivatives blocked by acetylation, polyethylene glycol having a weight average molecular weight of 200 to 2,000, preferably 200 to 600, polyalkylene glycol such as polypropylene glycol having a weight average molecular weight of 300 to 2,000, preferably 300 to 1,000 Dimethyl phthalate (DMP), diethyl phthalate (DEP), dibutyl phthalate (DBP), heptylnonyl phthalate (HNP), di-2-ethylhexyl phthalate (DOP), di-n-phthalate Cutyl (DNOP), di-i-octyl phthalate (DCapP), phthalic acid (79 alkyl) (D79P), di-i-decyl phthalate (DIDP), ditridecyl phthalate (DTDP), dicyclohexyl phthalate (DCHP) Phthalate plasticizers such as butyl benzyl phthalate (BDP), ethyl phthalyl ethyl glycolate (EPEG), butyl phthalyl butyl glycolate (BPBG), adipic acid-di-2-ethylhexyl (DOA), adipine Acid-di- (methylcyclohexyl), diisodecyl adipate (DIDA), azelaic acid-di-n-hexyl (DNHZ), azelaic acid-di-2-ethylhexyl (DOZ), dibutyl sebacate (DBS), dibasic sebacate Aliphatic dibase such as 2-ethylhexyl (DOS) Ester plasticizers, citrate plasticizers such as triethyl citrate (TEC), tributyl citrate (TBC), triethyl citrate (ATEC), tributyl acetyl citrate (ATBC), and epoxies such as epoxidized soybean oil And polyester plasticizers such as phosphate plasticizers such as tributyl phosphate (TBP), triphenyl phosphate (TPP), tricresyl phosphate (YCP), and tripropylene glycol phosphate.
[0036]
Next, as photopolymerization initiators in the initiator system, 1,3-di (t-butyldioxycarbonyl) benzophenone, 3,3 ′, 4,4′-tetrakis (t-butyldioxycarbonyl) benzophenone, Examples thereof include N-phenylglycine, 2,4,6-tris (trichloromethyl) -s-triazine, 3-phenyl-5-isoxazolone, 2-mercaptobenzimidazole, and imidazole dimers. The photopolymerization initiator is preferably decomposed after hologram recording from the viewpoint of stabilization of the recorded hologram. For example, organic peroxides are preferable because they are easily decomposed by irradiation with ultraviolet rays.
[0037]
Sensitizing dyes include thiopyrylium salt dyes having absorption light at 350 to 600 nm, merocyanine dyes, quinoline dyes, styrylquinoline dyes, ketocoumarin dyes, thioxanthene dyes, xanthene dyes, oxonol dyes, cyanine Examples include dyes, rhodamine dyes, thiopyrylium salt dyes, pyrylium ion dyes, and diphenyliodonium ion dyes. A sensitizing dye having absorption light in a wavelength region of 350 nm or less or 600 nm or more may be used.
[0038]
As the matrix polymer, polymethacrylate or partial hydrolyzate thereof, polyvinyl acetate or hydrolyzate thereof, polyvinyl alcohol or partial acetalized product thereof, triacetyl cellulose, polyisoprene, polybutadiene, polychloroprene, silicone rubber, Polystyrene, polyvinyl butyral, polychloroprene, polyvinyl chloride, chlorinated polyethylene, chlorinated polypropylene, poly-N-vinylcarbazole or a derivative thereof, poly-N-vinylpyrrolidone or a derivative thereof, a copolymer of styrene and maleic anhydride or Its half-ester, acrylic acid, acrylic ester, methacrylic acid, methacrylic ester, acrylamide, acrylonitrile, ethylene, propylene, vinyl chloride, vinyl acetate, etc. Copolymers and at least one polymerizable component of ability monomer group, or a mixture thereof is used. Preferably polyisoprene, polybutadiene, polychloroprene, polyvinyl alcohol, polyvinyl acetal which is a partial acetalized product of polyvinyl alcohol, polyvinyl butyral, polyvinyl acetate, ethylene-vinyl acetate copolymer, vinyl chloride-vinyl acetate copolymer, etc. Or a mixture thereof.
[0039]
As a process for stabilizing the recorded hologram, there is a process of monomer transfer by heating. For this purpose, these matrix polymers preferably have a relatively low glass transition temperature and facilitate monomer transfer. is necessary.
[0040]
The photopolymerizable compound is used in a proportion of 10 to 1000 parts by weight, preferably 10 to 100 parts by weight, based on 100 parts by weight of the binder resin.
[0041]
The photopolymerization initiator is used in a proportion of 1 to 10 parts by weight, preferably 5 to 10 parts by weight, based on 100 parts by weight of the binder resin.
[0042]
The sensitizing dye is used in a proportion of 0.01 to 1 part by weight, preferably 0.01 to 0.5 part by weight, based on 100 parts by weight of the binder resin.
[0043]
In addition, examples of the photosensitive material component include various nonionic surfactants, cationic surfactants, and anionic surfactants.
[0044]
These hologram recording materials are acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, benzene, toluene, xylene, chlorobenzene, tetrahydrofuran, methyl cellosolve, ethyl cellosolve, methyl cellosolve acetate, ethyl cellosolve acetate, ethyl acetate, 1,4-dioxane. 1,2-dichloroethane, dichloromethane, chloroform, methanol, ethanol, isopropanol, or a mixed solvent thereof is used to form a coating solution having a solid content of 15% to 25%. The film thickness after drying of the hologram recording layer is 0.1 μm to 50 μm, preferably 5 μm to 20 μm.
Examples of such a hologram recording material include Omnidex 352 and 706 manufactured by DuPont.
[0045]
Next, the adhesive layers 3 and 4 will be described. Examples of the pressure-sensitive adhesive layer include acrylic resins, acrylic ester resins, and copolymers thereof. The pressure-sensitive adhesive layer can also be formed using a so-called two-component cross-linking pressure-sensitive adhesive that is cross-linked by adding an isocyanate-based cross-linking agent, a metal chelate-based cross-linking agent or the like at the time of use. The thickness of the pressure-sensitive adhesive layer is preferably 4 μm to 20 μm.
[0046]
The volume hologram laminate of the present invention is characterized in that a (meth) acrylic monomer is added to at least one of the pressure-sensitive adhesive layers 3 and 4. As the (meth) acrylic monomer, a low molecular weight component having a molecular weight of 100 to 5,000, particularly a monomer having a molecular weight of 100 to 2,000 may be used. If the molecular weight is less than 100, it becomes volatile, which is not preferable, and if it exceeds 5,000, the mobility to the adjacent layer decreases, and the purpose of addition may not be achieved.
[0047]
Examples of the (meth) acrylic monomer include acrylic monomers and methacrylic monomers described in the volume hologram layer, preferably methoxypolyethylene glycol methacrylate (weight average molecular weight 400), methoxydiethylene glycol (meth) acrylate, Examples thereof include polyethylene glycol di (meth) acrylate (weight average molecular weight 200) and trimethylolpropane tri (meth) acrylate.
[0048]
As the (meth) acrylic monomer, it is preferable to select a substance having compatibility with the components constituting the volume hologram layer. Further, it is required that the interference fringes recorded by moving into the volume hologram layer are not completely destroyed, or recording / reproduction is not disabled.
[0049]
The (meth) acrylic monomer is dissolved and dispersed in an organic solvent together with the above-mentioned pressure-sensitive adhesive. For example, it is coated and dried on a release paper to form a pressure-sensitive adhesive layer. The pressure-sensitive adhesive layer contains 2% by weight to 20% by weight. The content is preferably 5 to 15% by weight, and if it exceeds 20% by weight, the tackiness is inhibited, which is not preferable.
[0050]
In the present invention, when the pressure-sensitive adhesive layer to which the (meth) acrylic monomer is added is laminated on the volume hologram layer, the detailed reason is unknown, but the (meth) acrylic monomer is recorded on the hologram. The volume hologram layer has a function to swell the volume hologram layer, and the obtained reproduction wavelength can be shifted to the longer wavelength side than the recording wavelength, so it can be controlled to the desired reproduction wavelength such as the bright line of the illumination light source. It is possible to do.
[0051]
The relationship between the content of the recording wavelength shift substance in the pressure-sensitive adhesive layer and the reproduction wavelength in the volume hologram layer may be determined by the following experimental method.
[0052]
(Dependence of wavelength shift amount on amount of compound capable of photopolymerization)
Hologram recording film: PET film / volume hologram layer / polyvinyl chloride film ("Omnidex 706" manufactured by DuPont)
Adhesive film: The following composition and acrylic adhesive ("Nissetsu PE-118" manufactured by Nippon Carbide)
・ ・ ・ 100 parts by weight ・ Methyl ethyl ketone ・ ・ ・ 30 parts by weight ・ Toluene ・ ・ ・ 15 parts by weight ・ Ethyl acetate ・ ・ ・ To 15 parts by weight, the addition amount of trimethylolpropane triacrylate (TMPTA) is different. Add pressure-sensitive adhesives with various TMPTA concentrations, apply 15 μm of dry film thickness on the PET film, and prepare adhesive films respectively.
[0053]
First, hologram recording is performed on the hologram recording film with an argon laser having a specific wavelength of 488 nm, the polyvinyl chloride film is peeled off, and the adhesive film is attached to the hologram surface from the adhesive layer side.
[0054]
The obtained PET film / volume hologram layer / adhesive layer / PET film was baked for 15 minutes at 140 ° C., which is the condition in the actual processing process, and then spectral transmission was performed using “UV-2100PC” manufactured by Shimadzu Corporation. The rate is measured, the peak wavelength is measured, and the shift amount from the recording wavelength of 488 nm (peak wavelength −488 nm = Δλ) is calculated.
[0055]
The measurement results are shown in FIG. In FIG. 3, the unit of TMPTA concentration is 10 ⁻⁴ mol, which is the amount added per gram of acrylic pressure-sensitive adhesive. As shown in FIG. 3, when the amount of TMPTA added to the pressure-sensitive adhesive layer is 0, Δλ is negative, unreacted monomers and plasticizers move from the volume hologram layer to the pressure-sensitive adhesive layer, and the volume hologram layer contracts. It can be seen that the reproduction wavelength has shifted to the short wavelength side. Further, when the amount of TMPTA added increases, Δλ increases, and the reproduction wavelength shifts to the longer wavelength side.
[0056]
In the present invention, when the pressure-sensitive adhesive layer to which the (meth) acrylic monomer is added is laminated on the volume hologram layer, the detailed reason is unknown, but the reproduction wavelength can be controlled. At the same time, it has been found that it has the effect of expanding the reproduction wavelength band. That is, the volume hologram laminate of the present invention can cope with the bright line of the illumination light source having a sharp wavelength, and can stably obtain a bright hologram.
[0057]
Further, in the volume hologram laminate of the present invention, the content of the moving component added in the first pressure-sensitive adhesive layer and / or the second pressure-sensitive adhesive layer is balanced with the content in the volume hologram layer. If the movement of the moving component other than the (meth) acrylic monomer is not caused between the pressure-sensitive adhesive layer and the volume hologram layer, the reproduction wavelength can be further stabilized.
[0058]
Examples of these moving components include photopolymerizable compounds and plasticizers described as the constituent material of the volume hologram layer. These moving components may be the same as or different from the constituent components of the volume hologram layer. However, when a (meth) acrylic monomer is selected as the moving component, it is preferable to add it in consideration of the addition amount of the (meth) acrylic monomer which is the additive component in the present invention described above.
[0059]
In addition, examples of the moving component include tackifiers, surfactants, polyalkylene glycols, and the like. These transfer components are low molecular weight components having a molecular weight of 100 to 5,000, and those having a molecular weight of 100 to 2,000 are particularly preferable. If the molecular weight is less than 100, it becomes volatile, which is not preferable, and if it exceeds 5,000, the mobility to the adjacent layer decreases, and the purpose of addition may not be achieved. Moreover, it is preferable to select a substance having compatibility with the component constituting the volume hologram layer as the moving component to be contained in the pressure-sensitive adhesive layer. In addition, the interference fringes recorded by moving into the volume hologram layer are completely removed. It is required not to be destroyed or to make recording and reproduction impossible.
[0060]
Moreover, the moving component contained in the pressure-sensitive adhesive layer is preferably contained in the pressure-sensitive adhesive layer together with the (meth) acrylic monomer which is the above-described additive component, so that the adhesiveness is not impaired, and the total amount is 20 wt. However, the content is preferably set appropriately from the relationship with the content of the moving component in the volume hologram layer and the relationship with the desired reproduction wavelength.
[0061]
Next, the surface protective film 6 has transparency, and includes a polyethylene film, a polypropylene film, a polyfluorinated ethylene film, a polyvinylidene fluoride film, a polyvinyl chloride film, a polyvinylidene chloride film, an ethylene-vinyl alcohol film, Examples include polyvinyl alcohol film, polymethylmethacrylate film, polyethersulfone film, polyetheretherketone film, polyamide film, tetrafluoroethylene-perfluoroalkylvinylether copolymer film, polyester film such as polyethylene terephthalate film, and resin such as polyimide film. The film thickness is 2 μm to 200 μm, preferably 10 μm to 50 μm.
[0062]
When the volume hologram layer has adhesiveness in the volume hologram laminate, an adhesive layer, a volume hologram layer, or a surface protective film may be formed on the substrate. In general, the surface protective film contains a plasticizer. In this case as well, it is preferable to adjust the balance of the adhesive layer, the volume hologram layer, and the surface protective film in consideration of moving components.
[0063]
Although not shown, a hard coat treatment may be performed on the surface protective film as necessary for the purpose of enhancing the protection of the surface protective film surface. The hard coat treatment is, for example, a silicone type, fluorine-containing silicone type, melamine alkyd type, urethane-acrylate type (ultraviolet ray curable type), etc. by dipping coating, spray coating, roll coating method, film thickness of 1 μm to 50 μm, preferably 3 μm It is good to apply to ˜25 μm.
[0064]
Further, similarly, although not shown, a release treatment may be applied to the surface of the surface protective film 6 or the hard coat treated surface. The mold release treatment may be performed by dipping coating, spray coating, or roll coating coating with a fluorine-based release agent, a silicone-based release agent, a stearate-based release agent, a wax-based release agent, or the like.
[0065]
The volume hologram layer in the volume hologram laminate of the present invention may perform hologram recording with a single wavelength as the recording wavelength, or may perform color hologram recording with two or more wavelengths. Further, by adding a (meth) acrylic monomer to the pressure-sensitive adhesive layer, the reproduction wavelength can be shifted with respect to the recording wavelength.
[0066]
When holographic recording is performed at a single wavelength, the half-value width of the obtained reproduction wavelength region can be 30 nm or more, preferably 35 nm or more, and is obtained when recording color holograms at two or more wavelengths. The full width at half maximum of each reproduction wavelength region can be 20 nm or more, preferably 25 nm or more.
[0067]
The volume hologram laminate of the present invention can be controlled by adjusting its reproduction wavelength to the emission line wavelength of the illumination light source and can broaden the reproduction band, so that a bright hologram image is reproduced under the illumination light source. be able to.
[0068]
Next, the layer structure of the cross section of the volume hologram laminate production label of the present invention is shown in FIG. In the figure, 10 is a label for producing a volume hologram laminate, 11 is a release paper, and the same reference numerals as those in FIG.
[0069]
The volume hologram laminate production label of the present invention is used for producing the volume hologram laminate described above. As shown in FIG. 2, the first pressure-sensitive adhesive layer 3 and the volume hologram layer 5 are formed on the release paper 11. The second pressure-sensitive adhesive layer 4 and the surface protective film 6 are laminated.
[0070]
As the release paper 11, in addition to the release paper normally used, a release film obtained by releasing the surface of the polyethylene terephthalate film with a fluorine release agent or a silicone release agent may be used. The surface of the release paper that is not on the pressure-sensitive adhesive layer side may be subjected to a release treatment in order to avoid blocking by the pressure-sensitive adhesive protruding from the side of the label. In addition, the laminate may be so-called “half-punched” so that the laminate can be peeled off from the release paper at an appropriate size, and the release paper may have cuts such as perforations. .
[0071]
After the release paper 11 is peeled off, the label 10 is laminated on the base material from the first pressure-sensitive adhesive layer 3 side, and the volume hologram laminate shown in FIG. 1 is produced.
[0072]
【Example】
Hereinafter, the present invention will be described with reference to examples.
Example 1
(Preparation of transparent protective film / second adhesive layer / silicon separator)
On the silicon separator (Tokyo Cellophane Co., Ltd. “SP-PET05” film thickness of 50 μm), the following composition and acrylic adhesive (“Nissetsu PE-118” manufactured by Nippon Carbide)
・ ・ ・ 100 parts by weight ・ Methyl ethyl ketone ・ ・ ・ 30 parts by weight ・ Toluene ・ ・ ・ 15 parts by weight ・ Ethyl acetate ・ ・ ・ 15 parts by weight ・ Isocyanate-based crosslinking agent (“Nissetsu CK-101” manufactured by Nippon Carbide)
... 16 parts by weight of the pressure-sensitive adhesive solution was immediately applied with a comma coater so as to have a film thickness of 15 μm after drying. A polyethylene terephthalate film (“Lumirror T-60, film thickness 50 μm) manufactured by Toray Industries, Inc. was laminated to this.
[0073]
(Production of silicon separator A / first adhesive layer / silicon separator B)
On the silicon separator A (“SP-PET05” film thickness 50 μm manufactured by Tokyo Cellophane Co., Ltd.), the following composition and acrylic adhesive (“Nissetsu PE-118” manufactured by Nippon Carbide)
... 100 parts by weight, methyl ethyl ketone ... 30 parts by weight, toluene ... 15 parts by weight, ethyl acetate ... 15 parts by weight, methoxypolyethylene glycol methacrylate (weight average molecular weight 400, manufactured by Shin-Nakamura Chemical Co., Ltd.) 10 parts by weight of the pressure-sensitive adhesive solution was immediately applied with a comma coater so that the film thickness was 15 μm after drying. This was laminated with a silicon separator B (“SP-PET02” film thickness 50 μm, manufactured by Tokyo Cellophane Co., Ltd.).
[0074]
(Production of hologram recording film)
A Lippmann hologram was recorded with a 488 nm argon laser on a hologram recording film (Omnidex 706; manufactured by DuPont) consisting of a laminate of polyethylene terephthalate film (PET film: 50 μm) / hologram recording material / polyvinyl chloride film.
[0075]
(Production of hologram laminate)
The polyvinyl chloride film of the hologram recording film obtained above was peeled off, and the silicon separator A was peeled off from the silicon separator A / first adhesive layer / silicon separator B obtained above, and both were laminated, and PET Film / volume hologram layer / first pressure-sensitive adhesive layer / silicon separator B was obtained.
[0076]
The PET film is peeled off from this laminate, and the transparent protective film / second pressure-sensitive adhesive layer / silicon separator of the silicon separator obtained above is peeled off and laminated to form a transparent protective film / second pressure-sensitive adhesive layer / A volume hologram laminate label of the present invention consisting of hologram recording material / first pressure-sensitive adhesive layer / silicon separator B was obtained.
[0077]
When this label was heated at 140 ° C. for 15 minutes and spectral characteristics were evaluated, the reproduction wavelength was 498 nm, Δλ with respect to the recording wavelength was +10 nm, and the half-value width was 43 nm.
[0078]
(Comparative example)
A volume hologram laminate production label was produced in the same manner as in the first pressure-sensitive adhesive layer forming material in Example 1 except that methoxypolyethylene glycol methacrylate was removed. Similarly, when the spectral characteristics were evaluated, the reproduction wavelength was obtained. Was 472 nm and the full width at half maximum was 26 nm.
[0079]
(Example 2)
Instead of the hologram recording film in Example 1, a laser having a wavelength of 476 nm, 532 nm, and 647 nm was used for a hologram recording film (HRF800x001; manufactured by DuPont) made of PET film / hologram recording material / PET film. A color Lippmann hologram was recorded.
[0080]
Using the obtained hologram recording film, the volume hologram laminate label of the present invention comprising transparent protective film / second adhesive layer / hologram recording material / first adhesive layer / silicon separator B as in Example 1. Got.
[0081]
When this label was heated at 140 ° C. for 15 minutes and spectral characteristics were evaluated, the reproduction wavelengths were 487 nm, 544 nm, and 655 nm, respectively, and Δλ with respect to the recording wavelength was +12 nm, +12 nm, and +8 nm, and the half-value width. Were 21 nm, 23 nm, and 27 nm, respectively.
[0082]
【The invention's effect】
The volume hologram laminate and the volume hologram laminate production label of the present invention can be controlled to a desired reproduction wavelength and can broaden the reproduction band, so that a bright hologram image can be reproduced under an illumination light source. Can do.
[Brief description of the drawings]
FIG. 1 is a diagram for explaining a volume hologram laminate of the present invention in a sectional view thereof.
FIG. 2 is a view for explaining a volume hologram laminate production label of the present invention in a sectional view thereof.
FIG. 3 is a diagram for explaining the relationship between the addition amount of trimethylolpropane triacrylate in the pressure-sensitive adhesive layer and the amount of wavelength shift from the recording wavelength in the obtained volume hologram layer.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 is a volume hologram laminated body, 2 is a base material, 3 is a 1st adhesive layer, 4 is a 2nd adhesive layer, 5 is a volume hologram layer, 6 is a surface protection film, 10 is a label for volume hologram laminated body production, 11 is a release sheet.

Claims (6)

In a volume hologram laminate in which a first pressure-sensitive adhesive layer, a volume hologram layer, a second pressure-sensitive adhesive layer, and a surface protective film are sequentially laminated on a substrate, the first and / or second pressure-sensitive adhesive layer is an acrylic resin, An acrylic pressure-sensitive adhesive layer made of an acrylic ester resin or a copolymer thereof, wherein (meth) acrylic monomer is contained in the layer in an amount of 2 to 20% by weight , and the adhesiveness in the pressure-sensitive adhesive layer is Rutotomoni is not intended to be inhibited, the volume hologram layer is a hologram recording in a single-wavelength light, the volume hologram laminate, characterized in that the half-value width of the reproduction wavelength region is 30nm or more. In a volume hologram laminate in which a first pressure-sensitive adhesive layer, a volume hologram layer, a second pressure-sensitive adhesive layer, and a surface protective film are sequentially laminated on a substrate, the first and / or second pressure-sensitive adhesive layer is an acrylic resin, An acrylic pressure-sensitive adhesive layer made of an acrylic ester resin or a copolymer thereof, wherein (meth) acrylic monomer is contained in the layer in an amount of 2 to 20% by weight , and the adhesiveness in the pressure-sensitive adhesive layer is Rutotomoni is not intended to be inhibited, are color hologram recorded in the volume hologram layer is two or more wavelength light, the volume hologram laminate their half-width of the reproduction wavelength region, characterized in that at 20nm or more.   The volume hologram laminate according to claim 1 or 2, wherein the pressure-sensitive adhesive layer is a two-component cross-linking pressure-sensitive adhesive that is cross-linked by adding a cross-linking agent during use.   The volume hologram laminate according to any one of claims 1 to 3, wherein the volume hologram layer is made of a photopolymerizable compound and is hologram-recorded. In the label for producing a volume hologram laminate, in which a first pressure-sensitive adhesive layer, a volume hologram layer, a second pressure-sensitive adhesive layer, and a surface protective film are sequentially laminated on a release sheet, the first and / or second pressure-sensitive adhesive layers are An acrylic pressure-sensitive adhesive layer made of an acrylic resin, an acrylic ester resin, or a copolymer thereof, wherein (meth) acrylic monomer is contained in the layer in an amount of 2 to 20% by weight . Rutotomoni is assumed that adhesive is not inhibited, the volume hologram laminate produced label, wherein the half-value width of the reproduction wavelength band of the hologram recorded in the volume hologram layer is 30nm or more. In the label for producing a volume hologram laminate, in which a first pressure-sensitive adhesive layer, a volume hologram layer, a second pressure-sensitive adhesive layer, and a surface protective film are sequentially laminated on a release sheet, the first and / or second pressure-sensitive adhesive layers are An acrylic pressure-sensitive adhesive layer made of an acrylic resin, an acrylic ester resin, or a copolymer thereof, wherein (meth) acrylic monomer is contained in the layer in an amount of 2 to 20% by weight . Rutotomoni is assumed that adhesive is not inhibited, are color hologram recorded in the volume hologram layer is two or more wavelength light, the volume hologram laminate their half-width of the reproduction wavelength region, characterized in that at 20nm or more Production label.

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