JP4170747B2 - Transfer foil having a light diffraction layer - Google Patents

Description

【００１８】
ここで、６個のＲ₁は夫々互いに独立して水素原子またはメチル基を表わし、Ｒ₂は炭素数が１〜１６個の炭化水素基を表わし、ＸおよびＹは直鎖状または分岐鎖状のアルキレン基を表わす。ｌ、ｍ、ｎ、ｏ及びｐの合計を１００とした場合に、ｌは２０〜９０、ｍは０〜８０、ｎは０〜５０、ｏ＋ｐは１０〜８０、ｐは０〜４０の整数である。
【００１９】
上記式（１）で表わされるウレタン変性アクリル系樹脂は、例えば、好ましい１例として、メタクリル酸メチル２０〜９０モルとメタクリル酸０〜５０モルと２−ヒドロキシエチルメタクリレート１０〜８０モル、Ｚとしてイソボルニルメタクリレート０〜８０モルとを共重合して得られるアクリル共重合体であって、該共重合体中に存在している水酸基にメタクリロイルオキシエチルイソシアネート（２−イソシアネートエチルメタクリレート）を反応させて得られる樹脂である。
【００２０】
従って、上記メタクリロイルオキシエチルイソシアネートが共重合体中に存在している全ての水酸基に反応している必要はなく、共重合体中の２−ヒドロキシエチルメタクリレート単位の水酸基の少なくとも１０モル％以上、好ましくは５０モル％以上がメタクリロイルオキシエチルイソシアネートと反応していればよい。上記の２−ヒドロキシエチルメタクリレートに代えて又は併用して、Ｎ−メチロールアクリルアミド、Ｎ−メチロールメタクリルアミド、２−ヒドロキシエチルアクリレート、２−ヒドロキシエチルメタクリレート、２−ヒドロキシプロピルアクリレート、２−ヒドロキシプロピルメタクリレート、４−ヒドロキシブチルアクリレート、４−ヒドロキシブチルメタクリレート等の水酸基を有するモノマーも使用することができる。
【００２１】
以上の如く、水酸基含有アクリル系樹脂中に存在している水酸基を利用して、分子中に多数のメタクリロイル基を導入したウレタン変性アクリル系樹脂を主成分とする樹脂組成物によって、例えば、回析格子等を形成する場合には、硬化手段として紫外線や電子線等の電離放射線が使用でき、しかも高架橋密度でありながら柔軟性および耐熱性等に優れた回析格子等を形成することができる。
【００２２】
（光回折層の形成）剥離層２２、保護層２３、光回折層２４の形成は、上述したそれぞれの材料を溶剤に溶解または分散させて、適宜添加剤を添加するなどした組成物を、印刷またはコーティング法で、少なくとも１部に塗布し乾燥して、塗膜を形成すれば良い。また、電離放射線で架橋する硬化性樹脂は、そのままの無溶剤、または溶剤へ分散若しくは溶解した組成物インキを、印刷またはコーティング法で、少なくとも１部に塗布し、必要に応じて乾燥し、後述するように表面凹凸パターン（光回折パターン）を複製（エンボスともいう）した後に、電離放射線を照射して硬化して形成する。乾燥後の厚さとしては、剥離層２２は、通常、０．０１μｍ〜５．０μｍ程度、好ましくは０．５μｍ〜３．０μｍ程度である。該厚さは薄ければ薄い程良いが、０．１μｍ以上であればより良い成膜が得られて剥離力が安定する。保護層２３の厚さは１μｍ〜１０μｍ程度、光回折層２４の厚さは０．１μｍ〜１０μｍ程度である。
【００２３】
印刷方法としては、グラビア印刷、スクリーン印刷などが適用できる。コーティング方法としては、ロールート、リバースロールコート、グラビアコート、リバースグラビアコート、バーコート、ロッドコ−ト、キスコート、ナイフコート、ダイコート、コンマコート、フローコート、スプレーコートなどのコーティング方法が適用できる。
【００２４】
（光回折＝凹凸パターン）光回折層２４には、回折画像を有する転写部１０３とタイミングマーク１０１とを設け、該タイミングマーク１０１は転写部１０３（回折画像を有する）と相関する位置関係にあるようにする。即ち、図１（Ａ）のように、１つの転写部１０３に対して１つのタイミングマーク１０１を設け、該タイミングマーク１０１は転写部１０３（回折画像を有する）と１：１の相関する位置関係にあるようにする。従って、タイミングマーク１０１をセンサで読み取って、対応している転写部１０３の位置関係を認識して、該転写部１０３を被転写体の所定の位置へ転写できる。
【００２５】
そして、光回折層２４の転写部１０３は、２次元または３次元画像を再生可能な表面凹凸パターン（光回折パターン、回折画像）をが形成したものである。この表面凹凸パターンとしては、物体光と参照光との光の干渉による干渉縞の光の強度分布が凹凸模様で記録されたホログラムや回折格子が適用できる。この表面凹凸パターンは光回折パターンを形成しており、光が照射されると光を回折して、回折画像を再生し目視できるようになる。
また、光回折層２４のタイミングマーク１０１は、転写部１０３と同様に２次元または３次元画像を再生可能な表面凹凸パターンでもよいが、センサで読み取れればよいので、通常、回折格子又はマット状の表面凹凸パターンとする。
【００２６】
（ホログラム）ホログラムとしては、フレネルホログラム、フラウンホーファーホログラム、レンズレスフーリエ変換ホログラム、イメージホログラム等のレーザ再生ホログラム、及びレインボーホログラム等の白色光再生ホログラム、さらに、それらの原理を利用したカラーホログラム、コンピュータホログラム、ホログラムディスプレイ、マルチプレックスホログラム、ホログラフィックステレオグラム、ホログラフィック回折格子、電子線で直接描画する等の描画的に形成された回折格子などがある。
【００２７】
（回折格子）回折格子としては、ホログラム記録手段を利用したホログラフィック回折格子があげられ、その他、電子線描画装置等を用いて描画的に回折格子を作成することにより、計算に基づいて任意の回折光が得られる回折格子をあげることもできる。これらのホログラム、回折格子は、単一若しくは多重に記録しても、組み合わせて記録しても良い。
【００２８】
（凹凸パターンの複製）ホログラムおよび／または回折格子を記録する表面凹凸パターン（光回折パターン）は、光回折層２４の金属光沢の反射層の側に設ける。光回折パターンを複製する際には、マスターそのものも使用できるが、摩耗や損傷の恐れがあるため、アナログレコード等におけるのと同様、マスターに金属メッキまたは紫外線硬化樹脂を塗布し、紫外線を照射して硬化させて剥がす等の方法により、金属または樹脂による複製を行ない、複製された型を使用して商業的複製を行なう。
【００２９】
（大量複製）商業的複製の方法は、金型または樹脂型を利用し、熱可塑性の合成樹脂、又は常温で固体状の電離放射線硬化性樹脂を素材として使用し、プレス（エンボスともいう）によりホログラムを複製するか、または、金型または樹脂型面に電離放射線硬化性樹脂などの液状の樹脂を塗布し、紫外線や電子線を照射して硬化させた後に、剥離して複製する。この商業的な複製は、長尺状で行うことで連続な複製作業ができて、ホログラムを一方の表面に有する光回折層２４が得られる。
【００３０】
（透明反射層）光回折層２４に設けた光回折パターンは、該光回折パターン面に透明反射層２５を設けることにより、ホログラムの再生像および／または回折格子が明瞭に視認できるようになる。該透明反射層２７は、その光学的な屈折率が光回折層２４のそれとは異なることにより、光回折画像、ホログラムを視認できるものとできる。該透明反射層２７として、光回折層２４とは異なる屈折率を有するものを用いると、ほぼ無色透明な色相で、金属光沢が無いにもかかわらず、ホログラムが視認できるから、透明なホログラムを作製することができる。例えば、光回折層２４と屈折率に差のある透明金属化合物が適用でき、光回折層２４よりも光の屈折率の高い薄膜、および光の屈折率の低い薄膜とがあり、前者の例としては、ＺｎＳ、ＴｉＯ₂、Ａｌ₂Ｏ₃、Ｓｂ₂Ｓ₃、ＳｉＯ、ＳｎＯ₂、ＩＴＯ等があり、後者の例としては、ＬｉＦ、ＭｇＦ₂、ＡｌＦ₃がある。透明金属化合物の形成は、光回折層２４面に、０．０１〜０．１μｍ程度、好ましくは０．０３〜０．０８μｍの厚みになるよう、蒸着、スパッタリング、イオンプレーティングなどの真空薄膜法などにより設ければよい。
【００３１】
（他の反射層）光回折層２４には透明反射層２５を設けたが、センサ側から見てタイミングマーク１０１と印刷部３３とに影響のない部分へは、金属光沢の反射層を設けてもよい。例えば、真空成膜法でアルミニウムなどの金属薄膜を全面に形成した後に、レジストを印刷しエッチング又は洗い出ししたり、セルロース誘導体で表面処理した金属蒸着膜細片を含有させた高輝度インキを用いて、グラビア印刷又はスクリーン印刷などの印刷法で、金属光沢の反射をする高輝度インキ反射層を設けたりしてもよい。高輝度インキを用いた印刷法であれば、高価な真空蒸着機を用いず、既存の印刷設備で製造することができる。また、高輝度インキ反射層を用いて印刷法で部分的に設け、また、図示していない印刷絵柄と同調するように設けることで、意匠効果が高まる。
【００３２】
高輝度インキとしては、金属蒸着膜細片をセルロース誘導体で表面処理してインキ中への分散性を向上させて、インキ塗膜の金属光沢を高輝度としたものである。該インキは、セルロース誘導体で表面処理した金属蒸着膜細片、バインダ、添加剤、及び溶剤からなり、必要に応じてグラビアインキ、スクリーンインキ、又はフレキソインキ化すればよい。例えば、ファインラップ−スーパーメタリックインキ（大日本インキ化学工業社製、高輝度インキ商品名）が例示できる。
高輝度インキの金属蒸着膜細片の金属としては、アルミニウムが適用できるが、必要に応じて、金、銀、銅、真鍮、チタン、クロム、ニッケル、ニッケルクロム、ステンレス等も使用できる。金属蒸着膜の厚さは、０．０１〜０．１μｍが好ましく、さらに好ましくは０．０３〜０．０８μｍであり、インキ中に分散させた金属蒸着膜細片の大きさは、５〜２５μｍが好ましく、さらに好ましくは１０〜１５μｍである。大きさが、この範囲未満の場合はインキ塗膜の輝度が不十分となり、この範囲を超えると、グラビア版のセルに入りにくく、またスクリーン版が目詰まりし易く、印刷塗膜の光沢が低下する。
【００３３】
金属蒸着膜細片は、まず、ポリエステルフィルム／剥離層／蒸着膜／表面の酸化防止トップコート層からなる蒸着フィルムを作成する。剥離層、トップコート層は、特に限定されないが、例えば、セルロース誘導体、アクリル樹脂、塩素化ポリプロピレンなどが適用できる。上記蒸着フィルムを、溶剤中に浸積して、金属蒸着膜を剥離、撹拌、濾別、乾燥して、金属蒸着膜細片を得る。該金属蒸着膜細片を温度１０〜３５℃、３０分程度、撹拌しながら、セルロース誘導体溶液を加え、金属蒸着膜細片の表面にセルロース誘導体を吸着させて、金属蒸着膜細片の表面処理を行う。セルロース誘導体の添加量は、金属がアルミニウムの場合は、蒸着膜細片に対して１〜２０質量％が好ましい。
【００３４】
該表面処理の後、金属蒸着膜細片を分離、又は金属蒸着膜細片スラリーをそのまま、バインダ、溶剤、必要に応じて、着色用顔料、染料、ワックス、可塑剤、レベリング剤、界面活性剤、分散剤、消泡剤、キレート化剤などの添加剤を配合、分散させてインキ化する。また、高輝度インキは、混練工程を必要とせず、攪拌機で混合するだけでよく分散し、金属光沢が損なわれない。即ち、高輝度の金属光沢を発現させるためには、金属蒸着膜細片の大きさが５〜２５μｍ程度が必要で、上記混練工程を行うと金属光沢が極端に低下してしまう。
【００３５】
（高輝度インキ印刷）以上のようにして得られたインキを、公知のグラビ印刷、スクリーン印刷、又はフレキソ印刷で、所要の絵柄を製版して、印刷し、乾燥、必要に応じて硬化すればよい。このようにして、部分的、又は任意の画像の金属光沢の反射層が得られる。また、金属光沢の反射層を着色してもよく、高輝度インキ中に染料及び／又は顔料を添加したり、金属蒸着膜細片へセルロース誘導体を吸着させる表面処理を行う際に、セルロース誘導体溶液に染料及び／又は顔料を添加したり、すればよい。また、該着色は透明でも不透明でもよく、不透明であればパール調、パステル調の外観が得られる。また、金属光沢の反射層の形成は、光回折層２４面、又は透明反射層２７面のどちらでもよい。
【００３６】
（層の組合せ）さらに、光回折層２４、透明反射層２７、印刷層３３の他に、図示していない絵柄印刷層、金属光沢の反射層を設けたり、また、絵柄印刷層を多色印刷法で不透明及び／又は透明インキとしたり、さらに、各層を入れ換えたり、さらにまた、それらの回折画像、絵柄、パターンを工夫し、かつ、それぞれの絵柄が意匠的に組み合わてもよい。このようにすると、「金属反射光回折画像部」、「着色有の金属反射光回折画像部」、「透明光回折画像部」、「着色有の透明反射光回折画像部」、「印刷画像部」とをそれぞれ任意の画像とすることができ、かつ、それぞれを任意に組合わせ、かつまた、それぞれが任意に混在した画像を得ることができる。
【００３７】
また、図示していない不透明インキからなる絵柄を光回折層２４より観察側に形成すれば、該不透明インキが光回折層２４及び／又は透明反射層２７及び／又は金属光沢の反射層を覆って隠蔽し、光回折層２４を隠し込むことができる。該隠し込み光回折画像は不透明インキを除去することで視認できるが、偽造者には隠してあることが判らずセキュリティ性が高まる。さらにまた、隠蔽された部分は「印刷画像」が、また、不透明インキがなく、隠蔽されていない部分は「金属反射光回折画像」、「着色有の金属反射光回折画像」、「透明光回折画像」、「着色有の透明反射光回折画像部」などの「光回折画像」が見える。即ち、「光回折画像」と「印刷画像」とが連続して見ることができる。このように、透明及び／又は不透明インキ層、光回折層２４、透明反射層２７、金属光沢の反射層を組み合わせることで、意匠性を著しく高めることができる。かつ、目視で容易に真偽が判定できるが、「金属反射光回折画像、透明光回折画像、印刷画像」が、複雑かつ相互に入り組んだ絵柄を構成しているので、偽造することは極めて困難で、セキュリティ性が高まる。また、印刷法のために小ロット生産にも対応でき、また、コストも低くできるという優れた効果を発揮する。
【００３８】
（印刷層）次に、透明反射層２７、又は金属光沢の反射層面へ、印刷層３３を設ける。印刷層３３は、公知の印刷法で印刷すればよい。印刷法としては、例えば、凹版印刷、孔版印刷、フレキソ印刷、樹脂凸版印刷、グラビアオフセット印刷等が適用できるが、グラビア印刷、スクリーン印刷が、長尺のウェブ状体へ帯状に印刷するのに適するので好適である。
【００３９】
印刷層に用いる印刷インキは、少なくともビヒクルと着色料とを含み、その粘度は、０．１〜３０００ポアズが好ましい。着色料は、無機顔料、有機顔料のうち１種類以上を含有する。無機顔料としては、フェロシアン化鉄、酸化鉄、カドミウム系顔料、酸化チタン、アルミナ、炭酸カルシウム、硫酸バリウムなどがあり、有機顔料としては、不溶性アゾ色素系、アゾレーキ系、スタロシアニン系、ケレート系、ニトロ系、ジオインジゴー系、アンスラキノン系、ペリレン系、キナクリドン系、スレン系、ジオキサジン系顔料としては縮合型アゾ系などがある。印刷層の色は、センサの読取精度から、不透明で濃色が好ましく、特に黒色が最も好ましい。
【００４０】
ビヒクルとしては、乾燥油、合成樹脂、天然樹脂、繊維系、ゴム誘導体のうち１種類以上が適用できる。乾燥油としては、亜麻仁油、シナキリ油、エノ油、大豆油、魚油、脱水ヒマシ油、スチレン化油、ビニルトルエン化油、マレイン油などがある。天然樹脂としては、ウッドロジン、重合ロジン、石灰硬化ロジン、亜鉛硬化ロジン、ロジンエステル、セラックなどがある。合成樹脂としては、フェノール樹脂、変性アルキド樹脂、ポリアミド樹脂、コールタールピッチ、ステアリンピッチなどがある。繊維系としては、ニトロセルロース、エチルセルロース、セルロースアセテート、セルロースアセテートプロピオネート、などがある。ゴム誘導体としては、環化ゴム、塩化ゴムなどがある。
【００４１】
該インキ組成物には、必要に応じて、硬化剤、充填剤、可塑剤、分散剤、潤滑剤、帯電防止剤、酸化防止剤、防黴剤、などの添加剤を、適宜加えても良い。
これらの組成物を、分散・混練して、また、必要に応じて、溶剤で固形分量や粘度を調整して、インキ組成物とする。該インキを、前記印刷法で印刷して、乾燥し、必要に応じて、温度３０℃〜７０℃で適宜エージングして熱硬化（反応）させ、または、紫外線、電子線などの電離放射線を照射し、硬化させて形成すれば良い。
【００４２】
（熱接着層）次に、反射層面に熱接着層２６を設ける。該熱接着層２６の材料としては、公知の加熱されると溶融または軟化して接着効果を発揮する感熱接着剤が適用でき、具体的には、塩化ビニール酢酸ビニール共重合樹脂、アクリル系樹脂、ポリエステル系樹脂などが挙げられる。該材料樹脂を溶剤に溶解または分散させて、適宜顔料などの添加剤を添加して、公知のロールコーティング、グラビアコーティングなどの方法で塗布し乾燥させて、厚さ０．１〜３０μｍ程度、好ましくは０．５〜１０μｍの層とする。
【００４３】
（タイミングマークの読取）次に、タイミングマーク１０１の読取について説明する。図１（Ｃ）は本発明の転写箔１を用いて、該転写箔１の所定の転写部１０３を、被転写体の所定の位置へ転写する概念図である。まず、転写箔１は巻きほぐされて、タイミングマーク１０１がセンサ１０７で読取可能な位置へ導いて走行するようにする。該読取可能な位置は、図１（Ａ）で平面的に図示するセンサ読取線上であり、下部を印刷部３３で覆われたタイミングマーク１０１が、所定の位置関係で並んでいる。さらに、該タイミングマーク１０１は、被転写体へ転写する転写部１０３と所定の位置関係としている。即ち、センサ１０７がタイミングマーク１０１を正確に読み取れれば、タイミングマーク１０１と所定の位置関係にある転写部１０３を、転写機の加熱した金型１０９の所定の位置へ停止させることができる。該金型１０９が下降し、転写箔１の熱接着層２６と被転写体とを加圧する。該熱接着層２６が、軟化又は溶融して被転写体と接着する。転写箔１を引き剥がすと転写基材２１のみが剥離し、剥離層／光回折層／透明反射層／熱接着層からなる転写層が転写部１０３となって、被転写体へ転写される。
【００４４】
転写時に最も重要なことは、タイミングマーク１０１をセンサ１０７が如何に精度良く読み取れるかである。タイミングマーク１０１と転写部１０３との位置関係は同時に形成するので、絵柄設計で決まり公差以上にズレることはない。従来の光回折層２４に設けたタイミングマーク１０１は、通常の安価なフォトセンサでは読み取れないので、レーザ光又は単波長の光源を有する特種なセンサを用いなればならず、さらに検出光が回折光であり正反射とは限らないので、センサの位置設定は、回折光の角度、しかも狭い角度範囲へ調整するために難しい。さらに、品目により回折角度が異なる場合が多く、品目毎に調整をやり直し必要がある。
【００４５】
そこで、本発明者は種々検討の結果、タイミングマーク１０１の下部へ印刷層３３設け、しかも該印刷層３３がタイミングマーク１０１を覆い、図１（Ａ）のように転写箔１の走行方向に対して帯状に設けることで、従来の該タイミングマーク１０１であっても、通常のバーコードなどの読取センサ１０７で読み取れて、同期をとって被転写体の所定の位置へ転写できることを見出した。このようにすると、タイミングマーク１０１と帯状の印刷部３３とのコントラストが高くなって、通常のバーコードなどの読取センサ１０７で、容易に読み取ることができる。
【００４６】
（読取精度）例えば、印刷部３３として公知のグラビア印刷法で、通常の墨グラビアインキを用いて、厚さ２μｍの印刷層とした。墨インキとは当業者が一般的に呼ぶ黒インキのことであり、原理的に完全な黒インキは現在でも得られていないので、墨インキと称している。なお、タイミングマーク１０１としては、マット画像をレーザ２光束法で撮影して用いた。このタイミングマーク１０１と印刷部３３とを有し、他の層は明細書で述べてきたように形成して、転写箔１を得た。該転写箔１は、図１（Ｃ）のように、センサで読み取ったところ、タイミングマーク１０１の信号量（Ｓ）は９１で、印刷部３３の信号量（Ｎ）は２５であった。読取精度に影響するＳ／Ｎ比＝９１／２５＝３．６４であった。
一方、墨インキの印刷層を設けない以外は同様にして、従来タイプの転写箔１を得た。該転写箔１のタイミングマークを、センサで読み取ったところ、タイミングマーク１０１の信号量（Ｓ）は３７０で、他の部分の信号量（Ｎ）は３２０であった。読取精度に影響するＳ／Ｎ比＝３７０／３２０＝１．１６であった。従来タイプのＳ／Ｎ比が１．１６に対した、本発明では３．６４と著しく高くできた。
【００４７】
従来タイプでは、主に熱接着層２６の光に埋もれてしまっていた。該熱接着層２６は、転写時の箔切れ性を高めるために、シリカなどの顔料を添加したり、塗布時にブラッシングという白化処理をする。このため、特に光の散乱性が高まり、タイミングマーク１０１と印刷部３３の共に顕著な信号量を発しているが、Ｓ／Ｎ比としては少なく、信号量の差がなく光に埋もれる結果となっていた。また、本発明の印刷層としては、墨色（黒色に近い）が好ましいが、不透明で濃色であれば使用することができる。Ｓ／Ｎ比で２．０以上程度、好ましくは３．０以上である。
【００４８】
なお、予め形成してある絵柄の位置へ合わせて（当業者では見当を合わせるという）印刷を刷り重ねる場合には、流れ方向及び幅方向の両方向の位置関係（見当）をピッタリ合わせねばならない。しかし、本発明では、帯状の絵柄であり、タイミングマーク１０１を覆っていればよく、幅方向のみのラフな見当合わせでよい。長尺のウェブ状で印刷する本発明では、幅方向の見当合わせは、当業者には極めて容易である。
【００４９】
【実施例】
（実施例１）まず、転写基材２１として、厚さ１２μｍのルミラーＦタイプ（東レ社製、ポリエステルフィルム商品名）を用いた。この一方の面へ、剥離ニス４５−３（昭和インク社製、アクリル系樹脂の剥離インキ商品名）を固形分１０質量％となるように溶剤で稀釈して、ロールコーティング法で、乾燥後の厚さが１μｍになるように塗布し乾燥して、剥離層２２を形成した。該剥離層２２面へ、ユピマーＬＺ０６５（三菱化学社製、紫外線硬化樹脂商品名）を固形分２５質量％となるように溶剤で稀釈して、リバースロールコーティング法で、乾燥後の厚さが３μｍになるように塗布し乾燥して、光回折層２４を形成した。該光回折層２４面へ、スタンパを加圧（エンボス）してレリーフを賦形する。別途、タイミングマーク（すりガラス状）及び立体模型をレーザー光を用いて、撮影したマスターホログラムから、２Ｐ法で複製したスタンパを複製装置のエンボスローラーに貼着して、１５０℃で相対するローラーと間で加熱プレス（エンボス）して、微細な凹凸パターンからなるレリーフを賦形させた。賦形後直ちに、高圧水銀灯で波長が２００〜４００ｎｍの紫外線を照射して硬化させた。
該光回折層２４面へ、厚さ４００ｎｍの硫化亜鉛を真空蒸着法で形成して透明反射層２７とした。透明反射層２７を覆って図１（Ａ）のように帯状に、グラビア印刷法で、乾燥後の厚さが２μｍになるように、カーボンブラックを着色料とした通常のグラビア墨インキを印刷して、印刷層３３を形成した。該印刷層３３面へ、塩化ビニル酢酸ビニル共重合体が２５質量％、マイクロシリカ２５質量％となるように溶剤で稀釈して、グラビア印刷法で、乾燥後の厚さが２μｍになるように、全面に塗布し乾燥して、熱接着層２６を形成して、本発明の光回折層を有する転写箔１（転写基材／剥離層／光回折層／透明反射層／印刷層／熱接着層）を得た。該転写箔１は、図１（Ｃ）のように、センサで読み取ったところ、タイミングマーク１０１の信号量（Ｓ）は９１で、印刷部３３の信号量（Ｎ）は２５であった。読取精度に影響するＳ／Ｎ比＝９１／２５＝３．６４と良好であった。通常のフォトセンサでも十分に読み取ることができた。
【００５０】
（実施例２）透明反射層２７と印刷層３３との間へ高輝度インキ反射層を設ける以外は、実施例１と同様にして、実施例２の発明の光回折層を有する転写箔１（転写基材／剥離層／光回折層／透明反射層／高輝度インキ反射層／印刷層／熱接着層）を得た。高輝度インキ反射層は、光回折層２４の賦形されているタイミングマーク１０１とは重ならないように、５ｍｍ以上離して形成した。該転写箔１は、図１（Ｃ）のように、センサで読み取ったところ、タイミングマーク１０１の信号量（Ｓ）は９１で、印刷部３３の信号量（Ｎ）は２５であった。読取精度に影響するＳ／Ｎ比＝９１／２５＝３．６４と良好であった。
【００５１】
（実施例３）光回折層２４としてユピマーＬＺ０６５の代わりに、ＳＵＺ６００（ザ・インクテック社製、紫外線硬化樹脂商品名）を用いる以外は、実施例１と同様にして、実施例３の本発明の光回折層を有する転写箔１（転写基材／剥離層／光回折層／透明反射層／印刷層／熱接着層）を得た。該転写箔１は、図１（Ｃ）のように、センサで読み取ったところ、タイミングマーク１０１の信号量（Ｓ）は９１で、印刷部３３の信号量（Ｎ）は２５であった。読取精度に影響するＳ／Ｎ比＝９１／２５＝３．６４であった。
【００５２】
（実施例４）印刷層３３としてグラビア紺色インキを用いる以外は、実施例１と同様にして、実施例４の本発明の光回折層を有する転写箔１（転写基材／剥離層／光回折層／透明反射層／印刷層／熱接着層）を得た。該転写箔１は、図１（Ｃ）のように、センサで読み取ったところ、タイミングマーク１０１の信号量（Ｓ）は９１で、印刷部３３の信号量（Ｎ）は４５であった。読取精度に影響するＳ／Ｎ比＝９１／４５＝２．０２であった。通常のフォトセンサで読み取ることができた。
【００５３】
（比較例１）印刷層３３を設けない以外は、実施例１と同様にして、比較例１の従来の光回折層を有する転写箔（転写基材／剥離層／光回折層／透明反射層／熱接着層）を得た。該転写箔１は、図１（Ｃ）のように、センサで読み取ったところ、タイミングマーク１０１の信号量（Ｓ）は３７０で、他の部分の信号量（Ｎ）は３２０であった。読取精度に影響するＳ／Ｎ比＝３７０／３２０＝１．１６であった。通常のフォトセンサで読み取ってみたが、１０回読み取って１回しか読み取ることができなかった。
【００５４】
【発明の効果】
本発明の光回折層を有する転写箔によれば、従来のタイミングマーク１０１であっても、帯状の印刷部３３とのコントラストが高くなって、通常のバーコードなどの読取センサ１０７で、容易に読み取ることができる。転写部を同期をとって、被転写体の所定の位置へ転写できる。
また、印刷層は帯状の絵柄であり、幅方向のみの検討合わせでよく、長尺のウェブ状で印刷するので、幅方向の見当合わせは極めて容易である。
さらに、本発明の光回折層を有する転写箔によれば、各層を組み合わせて、「金属反射光回折画像部」、及び／又は「着色有の金属反射光回折画像部」、及び／又は「透明光回折画像部」、及び／又は「着色有の透明反射光回折画像部」、及び／又は「印刷画像部」の画像がそれぞれ任意で、かつ、それぞれを任意に組合わすことができる。このように優れた意匠性及びセキュリティ性を併せ持つ。さらにまた、目視で容易に真偽が判定できるが、「金属反射光回折画像、透明光回折画像、印刷画像」が、複雑かつ相互に入り組んだ絵柄を構成しているので、偽造することは極めて困難でセキュリティ性が高まる。
【図面の簡単な説明】
【図１】 本発明の１実施例を示す平面図、側面図、及び断面図である。
【符号の説明】
１ 転写箔
２１ 転写基材
２２ 剥離層
２３ 保護層
２４ 光回折層
２６ 熱接着層
２７ 透明反射層
３３ 印刷部
１０１ タイミングマーク
１０３ 転写部
１０７ センサ
１０９ 金型[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a transfer foil. More specifically, the present invention relates to a diffraction image of an optical diffraction layer and a timing mark of an optical diffraction structure formed at a certain correlation position with a sensor, and synchronizes to a predetermined position of a transfer target. The present invention relates to a transfer foil having a light diffraction layer to be transferred.
[0002]
[Prior art]
(Technical Background) When transferring a light diffraction image of a transfer foil having a light diffraction layer to a predetermined position on a transfer target, the light diffraction image other than the endless pattern is aligned (synchronized) and transferred. There is a need to. Usually, a timing mark (also referred to as a register mark, a registration mark, a register mark, a register mark, etc.) of an optical diffraction structure is provided at a relative position to the diffraction image of the optical diffraction layer, and the timing mark is read by a sensor. Then, the diffraction image is transferred to a predetermined position of the transfer target body (synchronized).
[0003]
(Prior Art) Conventionally, a method is known in which a register mark (corresponding to a timing mark of the present application) is attached to a blank portion of a hologram image, and a reading position is corrected by a sensor (see, for example, Patent Document 1). However, the timing mark of the light diffraction structure has a drawback that a special sensor is required because the diffraction light from the mark must be read.
Further, a method of reading light from a mark with a line sensor is known (for example, see Patent Document 2). However, the illumination light source for illuminating the mark has a problem that a special light source is required to illuminate the laser beam with slit light.
[0004]
[Patent Document 1]
Japanese Patent Laid-Open No. 9-226770
[Patent Document 2]
JP 10-329831 A
[0005]
[Problems to be solved by the invention]
Accordingly, the present invention has been made to solve such problems. The purpose is to provide an opaque, dark, particularly preferably black, print layer under the timing mark of the light diffraction structure, which can be easily read by existing inexpensive sensors, and the desired light diffraction image is transferred. It is to provide a transfer foil that can be transferred to a predetermined position of a body.
[0006]
[Means for Solving the Problems]
In order to solve the above problems, a transfer foil having an optical diffraction layer according to the invention of claim 1 is formed by sequentially laminating at least a light diffraction layer, a transparent reflective layer, and an adhesive layer on one surface of a substrate. Has a light diffraction layer In transfer foil, Said An optical diffraction image and an optical diffraction timing mark are provided on the optical diffraction layer, and the optical diffraction timing mark is The light It is in a positional relationship that correlates with the diffraction image, and The To cover the timing mark, Opaque and dark Print layer Said With light diffraction layer Said Provided in a band between the adhesive layer, The optical diffraction timing mark can be read by an optical reading sensor. It is what I did. According to the present invention, a desired light diffraction image can be transferred to a predetermined position of a transfer object, which can be read by an existing inexpensive sensor, and the timing mark is not transferred to the transfer object but transferred to the transfer foil. A remaining transfer foil is provided.
The transfer foil having the light diffraction layer according to the invention of claim 2 is: When reading with the optical reading sensor, the S / N ratio is 2.0 or more when the signal amount of the optical diffraction timing mark is S and the signal amount of the printing unit is N. It is what I did. ADVANTAGE OF THE INVENTION According to this invention, the transfer foil which has a timing mark which can be read easily and is excellent in reading accuracy with the existing well-known cheap sensor is provided.
[0007]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a plan view, a side view, and a sectional view showing an embodiment of the present invention.
(Layer Configuration) FIG. 1 (A) is a plan view of the transfer foil 1 of the present invention, FIG. 1 (B) is a sectional view taken along the line AA of FIG. 1 (A), and FIG. 1 (C) is the transfer foil of the present invention. 1 is a side view illustrating transfer using 1. FIG. In the transfer foil 1 of the present invention, at least a light diffraction layer 24, a transparent reflection layer 27, and an adhesive layer 26 are sequentially laminated on one surface of a transfer base material 21 (also simply referred to as a base material). If necessary, a release layer 22 and / or a protective layer 23 may be provided between the transfer substrate 21 and the light diffraction layer 24.
(Mark Positional Relationship) The optical diffraction layer 24 is provided with a transfer portion 103 having a diffraction image and a timing mark 101, and the timing mark 101 has a positional relationship correlated with the transfer portion 103 (having a diffraction image). To be. Further, a print layer 33 is provided between the light diffraction layer 24 and the adhesive layer 26, and the print layer 33 is provided in a strip shape so as to cover the timing mark 101. This printed layer is preferably opaque and dark, most preferably black. The size of the diffraction image formed on the transfer unit 103 may be larger or smaller than the size of the transfer unit 103. If it is large, the entire transfer portion 103 becomes a diffracted image, and if it is small, there is no influence other than that it becomes a fringed diffraction image.
[0008]
(Transfer) Such a transfer foil 1 of the present invention is heated using a transfer machine (also referred to as foil stamping or hot stamping) whose concept is shown in the side view of FIG. The transfer portion 103 corresponding to the mold is transferred to the transfer body by applying pressure to the transfer body and peeling off the transfer substrate 21.
When transferring the transfer portion 103 having the diffraction image of the transfer foil 1 to a predetermined position on the transfer object, conventionally, a timing mark 101 of an optical diffraction structure is provided at a relative position to the diffraction image of the optical diffraction layer 24. Then, the timing mark 101 is read by the sensor 107 and synchronized, and transferred to a predetermined position of the transfer target. However, since the conventional timing mark 101 is an optical diffraction structure because it is formed simultaneously with the diffraction image of the optical diffraction layer 24, and the timing mark emits diffracted reproduction light, it cannot be read by an ordinary reading sensor such as a barcode. Need special sensors to read mechanically.
[0009]
(Point of the Invention) Therefore, the present inventor can read the conventional timing mark 101 with a reading sensor 107 such as a normal bar code and transfer it to a predetermined position of the transfer target in synchronization. As a result, the present invention has been achieved. As in the prior art, a transfer portion 103 having a diffracted image and a timing mark 101 are provided on the optical diffraction layer 24, and further, a printing layer 33 is provided below the timing mark 101. Covering and providing a strip shape as shown in FIG. 1A causes a background effect.
In this way, the contrast between the timing mark 101 and the strip-shaped printing unit 33 is increased, and can be easily read by the reading sensor 107 such as a normal barcode. Conventional timing marks are mainly buried in the light of the thermal bonding layer 26. The thermal adhesive layer 26 is prominent because a pigment such as silica is added in order to enhance the foil breakability during transfer, or a whitening treatment such as brushing is applied during application. Since the timing mark 101 formed by the optical diffraction layer that has been difficult to read in the past is read, the diffraction image formed in the same manner as the timing mark 101 can be accurately transferred to a desired position on the transfer target. The printed layer of the present invention is opaque and preferably has a dark color, and black is particularly preferable.
[0010]
Next, the material of the transfer foil 1 of the present invention will be described.
(Transfer foil) FIG. 1B is a sectional view of a transfer foil showing an embodiment of the present invention. The transfer foil 1 is provided with a transfer base material 21, if necessary, a peeling layer 22 and / or a protective layer, a light diffraction layer 24, a transparent reflection layer 25, a printing layer 33, and a heat bonding layer 26. Further, if the release layer 22 is provided as necessary, the releasability at the time of transfer becomes more stable, and if a protective layer is provided as necessary, for example, the light diffraction layer 24 transferred to the transfer object. In addition, the durability against abrasion and scratches due to external force is improved.
[0011]
(Transfer Base Material) As the material of the transfer base material 21, various materials can be applied depending on the use as long as they have mechanical strength, heat resistance and the like that can withstand manufacturing and transfer operations. For example, polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polyethylene terephthalate-isophthalate copolymer, terephthalic acid-cyclohexanedimethanol-ethylene glycol copolymer, polyethylene terephthalate / polyethylene naphthalate Polyester resins such as coextruded films, polyamide resins such as nylon 6, nylon 66 and nylon 610, polyolefin resins such as polyethylene, polypropylene and polymethylpentene, vinyl resins such as polyvinyl chloride, polyacrylates and polymetas Acrylic resins such as acrylate / polymethyl methacrylate, imide resins such as polyimide / polyamideimide / polyetherimide, polyarylate / polysulfone・ Polyethersulfone ・ Polyphenylene ether ・ Polyphenylene sulfide (PPS) ・ Polyaramid ・ Polyetherketone ・ Polyethernitrile ・ Polyetheretherketone ・ Polyethersulfite engineering resin, polycarbonate, polystyrene ・ High impact Examples thereof include styrene resins such as polystyrene, AS resin, and ABS resin, and cellulose films such as cellophane, cellulose triacetate, cellulose diacetate, and nitrocellulose.
[0012]
The transfer substrate 21 may be a copolymer resin containing these resins as a main component, a mixture (including an alloy), or a laminate composed of a plurality of layers. The transfer substrate 21 may be a stretched film or an unstretched film, but a film stretched in a uniaxial direction or a biaxial direction is preferable for the purpose of improving the strength. The thickness of the transfer substrate 21 is usually about 2.5 to 100 μm, preferably 4 to 50 μm, and most preferably 6 to 25 μm. If the thickness exceeds this range, the thermal conductivity will be poor, the transfer will not be stable, and the cost will be high.If the thickness is less than this range, the mechanical strength will be insufficient and cutting will occur during the transfer. Sex is reduced.
The transfer substrate 21 is used as a film, sheet, or board formed of at least one layer of these resins. Usually, polyester-based films such as polyethylene terephthalate and polyethylene naphthalate have good balance in terms of strength, heat resistance and price, and are preferably used. Polyethylene terephthalate is particularly optimal.
Prior to application, the transfer substrate 21 is subjected to corona discharge treatment, plasma treatment, ozone treatment, flame treatment, primer (also called an anchor coat, adhesion promoter, or easy adhesive) coating treatment, pre-heat treatment, removal. Easy adhesion treatment such as dust treatment, vapor deposition treatment, and alkali treatment may be performed. Moreover, you may add additives, such as a filler, a plasticizer, a coloring agent, and an antistatic agent, to this resin film as needed. As the filler, extender pigments such as silica and calcium carbonate can be applied.
[0013]
(Peeling layer) A peeling layer 22 is provided on the surface of the transfer substrate 21 on which the protective layer 23 or the light diffraction layer 24 is formed in order to facilitate peeling. As the release layer 22, a releasable resin, a resin containing a release agent, a curable resin that is cross-linked by ionizing radiation, and the like can be applied. Examples of the release resin include fluorine resin, silicone, melamine resin, epoxy resin, polyester resin, acrylic resin, and fiber resin. Resins containing a release agent include, for example, acrylic resins, vinyl resins, polyester resins, and fiber-based resins to which release agents such as fluorine resins, silicones, and various waxes are added or copolymerized. is there. Examples of the curable resin that is cross-linked by ionizing radiation include a resin containing a monomer / oligomer having a functional group that is polymerized (cured) by ionizing radiation such as ultraviolet (UV) or electron beam (EB).
[0014]
(Protective layer) The protective layer 23 functions to enhance the peelability of the transfer substrate 21 and the light diffraction layer 24 and to protect the light diffraction layer 24 after the transfer substrate 21 is peeled off. Examples of the material of the protective layer 23 include acrylic resins, polyester resins, amide resins, cellulose resins, vinyl resins, urethane resins, olefin resins, epoxy resins, and the like. Although 5-5 micrometers is suitable, it is not limited to these. What is necessary is just to provide this protective layer 23 as needed, such as a use.
[0015]
(Light diffraction layer) The light diffraction layer 24 is colorless or colored, transparent or translucent, and may be a single layer or a multilayer, and the thermoplasticity capable of reproducing irregularities by casting or embossing. Resin, curable resin, or the photosensitive resin composition which can shape | mold a hardening part and an unhardened part according to light diffraction pattern information can be utilized. Specifically, for example, thermoplastic resins such as polyvinyl chloride, acrylic (polymethyl methacrylate), polystyrene, or polycarbonate, unsaturated polyester, melamine, epoxy, polyester (meth) acrylate, urethane (meth) acrylate, epoxy ( It is a thermosetting resin such as (meth) acrylate, polyether (meth) acrylate, polyol (meth) acrylate, melamine (meth) acrylate, or triazine acrylate, each of which is a single, a thermoplastic resin, or a thermosetting resin. It may be a mixture of comrades or a mixture of a thermoplastic resin and a thermosetting resin. An ionizing radiation curable resin composition having a radically polymerizable unsaturated group and having thermoformability or a radically polymerizable unsaturated monomer added can also be used.
[0016]
(Light diffraction layer) As the ionizing radiation curable resin, for example, epoxy-modified acrylate resin, urethane-modified acrylate resin, acrylic-modified polyester, etc. can be applied, preferably urethane-modified acrylate resin, particularly urethane represented by the following general formula A modified acrylic resin is preferred.
[0017]
[Chemical 1]

[0018]
Where 6 R ₁ Each independently represent a hydrogen atom or a methyl group, R ₂ Represents a hydrocarbon group having 1 to 16 carbon atoms, and X and Y represent a linear or branched alkylene group. When the total of l, m, n, o and p is 100, l is an integer from 20 to 90, m is from 0 to 80, n is from 0 to 50, o + p is from 10 to 80, and p is an integer from 0 to 40. is there.
[0019]
The urethane-modified acrylic resin represented by the above formula (1) is, for example, as a preferred example, 20 to 90 mol of methyl methacrylate, 0 to 50 mol of methacrylic acid, 10 to 80 mol of 2-hydroxyethyl methacrylate, Acrylic copolymer obtained by copolymerizing 0 to 80 mol of bornyl methacrylate, wherein methacryloyloxyethyl isocyanate (2-isocyanate ethyl methacrylate) is reacted with a hydroxyl group present in the copolymer. The resulting resin.
[0020]
Therefore, the methacryloyloxyethyl isocyanate need not react with all the hydroxyl groups present in the copolymer, preferably at least 10 mol% or more of the hydroxyl groups of 2-hydroxyethyl methacrylate units in the copolymer. It is sufficient that 50 mol% or more is reacted with methacryloyloxyethyl isocyanate. In place of or in combination with the above 2-hydroxyethyl methacrylate, N-methylol acrylamide, N-methylol methacrylamide, 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl acrylate, 2-hydroxypropyl methacrylate, Monomers having a hydroxyl group such as 4-hydroxybutyl acrylate and 4-hydroxybutyl methacrylate can also be used.
[0021]
As described above, by using a hydroxyl group present in a hydroxyl group-containing acrylic resin, a resin composition mainly composed of a urethane-modified acrylic resin in which a number of methacryloyl groups are introduced into the molecule, for example, diffraction. When forming a lattice or the like, ionizing radiation such as ultraviolet rays or electron beams can be used as a curing means, and a diffraction lattice or the like excellent in flexibility and heat resistance can be formed while having a high crosslinking density.
[0022]
(Formation of optical diffraction layer) The release layer 22, the protective layer 23, and the optical diffraction layer 24 are formed by printing a composition obtained by dissolving or dispersing each of the above-described materials in a solvent and adding an appropriate additive. Alternatively, it may be applied to at least one part by a coating method and dried to form a coating film. In addition, the curable resin that is cross-linked by ionizing radiation is a solvent-free composition as it is, or a composition ink dispersed or dissolved in a solvent is applied to at least one part by printing or a coating method, and dried as necessary. As described above, the surface irregularity pattern (light diffraction pattern) is duplicated (also referred to as embossing) and then cured by irradiation with ionizing radiation. As the thickness after drying, the release layer 22 is usually about 0.01 μm to 5.0 μm, preferably about 0.5 μm to 3.0 μm. The thinner the thickness is, the better. However, when the thickness is 0.1 μm or more, better film formation is obtained and the peeling force is stabilized. The protective layer 23 has a thickness of about 1 μm to 10 μm, and the light diffraction layer 24 has a thickness of about 0.1 μm to 10 μm.
[0023]
As a printing method, gravure printing, screen printing, or the like can be applied. As a coating method, a coating method such as low route, reverse roll coat, gravure coat, reverse gravure coat, bar coat, rod coat, kiss coat, knife coat, die coat, comma coat, flow coat, spray coat, etc. can be applied.
[0024]
(Light diffraction = uneven pattern) The light diffraction layer 24 is provided with a transfer portion 103 having a diffraction image and a timing mark 101, and the timing mark 101 has a positional relationship correlated with the transfer portion 103 (having a diffraction image). Like that. That is, as shown in FIG. 1A, one timing mark 101 is provided for one transfer portion 103, and the timing mark 101 has a 1: 1 correlated positional relationship with the transfer portion 103 (having a diffraction image). To be in. Therefore, the timing mark 101 can be read by a sensor, the positional relationship of the corresponding transfer unit 103 can be recognized, and the transfer unit 103 can be transferred to a predetermined position on the transfer target.
[0025]
The transfer portion 103 of the light diffraction layer 24 is formed with a surface unevenness pattern (light diffraction pattern, diffraction image) capable of reproducing a two-dimensional or three-dimensional image. As this surface concavo-convex pattern, a hologram or diffraction grating in which the intensity distribution of the interference fringe light due to the interference between the object light and the reference light is recorded in the concavo-convex pattern can be applied. The surface uneven pattern forms a light diffraction pattern. When light is irradiated, the light is diffracted and a diffraction image can be reproduced and visually observed.
Further, the timing mark 101 of the light diffraction layer 24 may be a surface uneven pattern that can reproduce a two-dimensional or three-dimensional image as in the transfer unit 103. However, since it can be read by a sensor, it is usually a diffraction grating or a mat-like pattern. The surface irregularity pattern of
[0026]
(Holograms) Holograms include Fresnel holograms, Fraunhofer holograms, lensless Fourier transform holograms, laser reproduction holograms such as image holograms, white light reproduction holograms such as rainbow holograms, color holograms utilizing these principles, and computers There are holograms, hologram displays, multiplex holograms, holographic stereograms, holographic diffraction gratings, and diffraction gratings formed in a drawing manner such as drawing directly with an electron beam.
[0027]
(Diffraction grating) As a diffraction grating, there is a holographic diffraction grating using a hologram recording means. In addition, any diffraction grating can be created by drawing using an electron beam drawing apparatus or the like, based on calculation. A diffraction grating capable of obtaining diffracted light can also be mentioned. These holograms and diffraction gratings may be recorded in a single or multiple manner or in combination.
[0028]
(Duplication of Concave / Concavity Pattern) A surface concavity and convexity pattern (light diffraction pattern) for recording a hologram and / or diffraction grating is provided on the side of the metallic diffraction reflective layer of the light diffraction layer 24. When replicating a light diffraction pattern, the master itself can be used, but there is a risk of wear and damage, so as with analog records, etc., a metal plating or UV curable resin is applied to the master and irradiated with UV light. The metal or resin is replicated by a method such as curing and peeling, and commercial replication is performed using the replicated mold.
[0029]
(Mass replication) Commercial replication uses molds or resin molds, uses thermoplastic synthetic resin or solid ionizing radiation curable resin at room temperature as a material, and press (also called emboss) The hologram is replicated, or a liquid resin such as an ionizing radiation curable resin is applied to the mold or resin mold surface and cured by irradiation with ultraviolet rays or electron beams, and then peeled off and replicated. This commercial duplication is carried out in a long shape, whereby a continuous duplication operation can be performed, and an optical diffraction layer 24 having a hologram on one surface is obtained.
[0030]
(Transparent Reflective Layer) The optical diffraction pattern provided on the optical diffraction layer 24 can clearly see the reproduced image of the hologram and / or the diffraction grating by providing the transparent reflective layer 25 on the surface of the optical diffraction pattern. The transparent reflection layer 27 can be viewed with a light diffraction image and a hologram because its optical refractive index is different from that of the light diffraction layer 24. If a transparent reflective layer 27 having a refractive index different from that of the light diffractive layer 24 is used, a hologram can be visually recognized although it has a substantially colorless and transparent hue and no metallic luster. can do. For example, a transparent metal compound having a refractive index difference from that of the light diffraction layer 24 can be applied, and there are a thin film having a higher refractive index of light than that of the light diffraction layer 24 and a thin film having a lower refractive index of light. ZnS, TiO ₂ , Al ₂ O _Three , Sb ₂ S _Three , SiO, SnO ₂ , ITO, etc. Examples of the latter include LiF, MgF ₂ , AlF _Three There is. The transparent metal compound is formed on the surface of the light diffraction layer 24 by a vacuum thin film method such as vapor deposition, sputtering, or ion plating so as to have a thickness of about 0.01 to 0.1 μm, preferably 0.03 to 0.08 μm. For example, it may be provided.
[0031]
(Other Reflective Layers) Although the transparent reflective layer 25 is provided in the light diffraction layer 24, a metallic glossy reflective layer is provided in a portion that does not affect the timing mark 101 and the printing unit 33 when viewed from the sensor side. Also good. For example, after a metal thin film such as aluminum is formed on the entire surface by vacuum film formation, a resist is printed and etched or washed out, or a high-brightness ink containing a metal vapor-deposited thin film surface treated with a cellulose derivative is used. Alternatively, a high-brightness ink reflecting layer that reflects metallic luster may be provided by a printing method such as gravure printing or screen printing. If it is a printing method using high-intensity ink, it can manufacture with the existing printing equipment, without using an expensive vacuum evaporation machine. In addition, the design effect is enhanced by providing a part with a printing method using a high-brightness ink reflecting layer and providing it in synchronization with a printing pattern (not shown).
[0032]
As the high-brightness ink, a metal vapor-deposited film strip is surface-treated with a cellulose derivative to improve dispersibility in the ink, and the metallic luster of the ink coating film is increased in brightness. The ink is composed of a metal vapor-deposited film strip surface-treated with a cellulose derivative, a binder, an additive, and a solvent, and may be formed into a gravure ink, a screen ink, or a flexo ink as necessary. For example, fine wrap-super metallic ink (Dainippon Ink Chemical Co., Ltd., high brightness ink product name) can be exemplified.
Aluminum can be used as the metal of the metal vapor-deposited film strip of the high-brightness ink, but gold, silver, copper, brass, titanium, chromium, nickel, nickel chromium, stainless steel, etc. can also be used as necessary. The thickness of the metal vapor deposition film is preferably 0.01 to 0.1 μm, more preferably 0.03 to 0.08 μm, and the size of the metal vapor deposition film dispersed in the ink is 5 to 25 μm. Is more preferable, and it is 10-15 micrometers more preferably. If the size is less than this range, the brightness of the ink coating will be insufficient, and if it exceeds this range, it will be difficult to enter the gravure plate cell, the screen plate will be clogged easily, and the gloss of the printed coating will decrease. To do.
[0033]
The metal vapor deposited film strip is first prepared as a vapor deposited film consisting of polyester film / release layer / deposited film / antioxidation top coat layer on the surface. The release layer and the topcoat layer are not particularly limited, and for example, cellulose derivatives, acrylic resins, chlorinated polypropylene, and the like can be applied. The vapor deposition film is immersed in a solvent, and the metal vapor deposition film is peeled, stirred, filtered and dried to obtain metal vapor deposition film strips. While the metal vapor-deposited film strip is stirred at a temperature of 10 to 35 ° C. for about 30 minutes, a cellulose derivative solution is added, and the cellulose derivative is adsorbed on the surface of the metal vapor-deposited film strip to treat the metal vapor-deposited film strip. I do. When the metal is aluminum, the addition amount of the cellulose derivative is preferably 1 to 20% by mass with respect to the deposited film strip.
[0034]
After the surface treatment, the metal vapor-deposited film strips are separated, or the metal vapor-deposited film strip slurry is left as it is, a binder, a solvent, and if necessary, a coloring pigment, a dye, a wax, a plasticizer, a leveling agent, a surfactant. Additives such as dispersants, antifoaming agents and chelating agents are blended and dispersed into ink. In addition, the high-brightness ink does not require a kneading step and can be dispersed only by mixing with a stirrer, and the metallic luster is not impaired. That is, in order to develop a high-brightness metallic luster, the metal vapor-deposited film strip needs to have a size of about 5 to 25 μm, and when the kneading step is performed, the metallic luster is extremely lowered.
[0035]
(High-brightness ink printing) If the ink obtained as described above is made by known gravure printing, screen printing, or flexographic printing, the required pattern is made, printed, dried, and cured if necessary. Good. In this way, a partially or any image metallic glossy reflective layer is obtained. In addition, the metallic luster reflective layer may be colored. When a dye and / or pigment is added to the high-brightness ink or the surface treatment is performed to adsorb the cellulose derivative to the metal vapor-deposited film strip, the cellulose derivative solution A dye and / or a pigment may be added to. The coloring may be transparent or opaque, and if opaque, a pearly or pastel appearance can be obtained. The metallic glossy reflective layer may be formed on either the surface of the light diffraction layer 24 or the surface of the transparent reflective layer 27.
[0036]
(Combination of layers) Further, in addition to the light diffraction layer 24, the transparent reflection layer 27, and the printing layer 33, a pattern printing layer (not shown) or a metallic glossy reflection layer is provided, or the pattern printing layer is printed in multiple colors. Opaque and / or transparent ink may be used by the method, each layer may be replaced, and the diffraction image, the pattern, and the pattern may be devised, and the respective patterns may be combined in design. In this way, the “metal reflection light diffraction image portion”, “colored metal reflection light diffraction image portion”, “transparent light diffraction image portion”, “colored transparent reflection light diffraction image portion”, “print image portion” "Can be used as arbitrary images, and can be arbitrarily combined with each other, and an image in which each of them is arbitrarily mixed can be obtained.
[0037]
Further, when a pattern made of opaque ink (not shown) is formed on the observation side from the light diffraction layer 24, the opaque ink covers the light diffraction layer 24 and / or the transparent reflection layer 27 and / or the metal glossy reflection layer. The light diffraction layer 24 can be concealed. The concealed light diffraction image can be visually recognized by removing the opaque ink. However, the concealed person does not know that the concealed light diffraction image is concealed, and the security is improved. Furthermore, the concealed part is a “printed image”, and the non-opaque ink is not concealed by a “metal reflected light diffraction image”, “colored metal reflected light diffraction image”, “transparent light diffraction”. “Light diffraction images” such as “image” and “colored transparent reflected light diffraction image portion” can be seen. That is, the “light diffraction image” and the “printed image” can be viewed continuously. Thus, the design can be remarkably enhanced by combining the transparent and / or opaque ink layer, the light diffraction layer 24, the transparent reflective layer 27, and the metallic glossy reflective layer. In addition, it is easy to visually determine whether it is true or false, but it is extremely difficult to forge because the “metal reflection light diffraction image, transparent light diffraction image, and print image” constitute a complex and interlaced pattern. This increases security. In addition, because of the printing method, it can be used for small-lot production, and it has the excellent effect of reducing costs.
[0038]
(Print layer) Next, the print layer 33 is provided on the transparent reflective layer 27 or the reflective surface of the metallic luster. The printing layer 33 may be printed by a known printing method. As the printing method, for example, intaglio printing, stencil printing, flexographic printing, resin relief printing, gravure offset printing, and the like can be applied, but gravure printing and screen printing are suitable for printing in a strip shape on a long web-like body. Therefore, it is preferable.
[0039]
The printing ink used for the printing layer contains at least a vehicle and a colorant, and the viscosity is preferably 0.1 to 3000 poise. The colorant contains one or more of inorganic pigments and organic pigments. Inorganic pigments include ferrocyanide, iron oxide, cadmium pigments, titanium oxide, alumina, calcium carbonate, barium sulfate, etc., and organic pigments include insoluble azo dyes, azo lakes, stalocyanines, and chelates. Nitro, geoindigo, anthraquinone, perylene, quinacridone, selenium, and dioxazine pigments include condensed azo pigments. The color of the print layer is opaque and preferably dark, and most preferably black, from the sensor reading accuracy.
[0040]
As the vehicle, one or more of dry oil, synthetic resin, natural resin, fiber, and rubber derivative can be applied. Examples of the dry oil include linseed oil, cinnabar oil, eno oil, soybean oil, fish oil, dehydrated castor oil, styrenated oil, vinyltoluene oil, and male oil. Examples of natural resins include wood rosin, polymerized rosin, lime-cured rosin, zinc-cured rosin, rosin ester, shellac and the like. Synthetic resins include phenolic resins, modified alkyd resins, polyamide resins, coal tar pitch, stearin pitch, and the like. Examples of the fiber system include nitrocellulose, ethyl cellulose, cellulose acetate, and cellulose acetate propionate. Examples of rubber derivatives include cyclized rubber and chlorinated rubber.
[0041]
If necessary, additives such as a curing agent, a filler, a plasticizer, a dispersant, a lubricant, an antistatic agent, an antioxidant, and an antifungal agent may be appropriately added to the ink composition. .
These compositions are dispersed and kneaded, and if necessary, the solid content and viscosity are adjusted with a solvent to obtain an ink composition. The ink is printed by the above printing method, dried, and if necessary, aged at a temperature of 30 ° C. to 70 ° C. and thermally cured (reacted), or irradiated with ionizing radiation such as ultraviolet rays and electron beams. And cured to form.
[0042]
(Thermal adhesive layer) Next, the thermal adhesive layer 26 is provided on the reflective layer surface. As the material of the thermal adhesive layer 26, a heat-sensitive adhesive that melts or softens when heated and exhibits an adhesive effect can be applied. Specifically, a vinyl chloride vinyl acetate copolymer resin, an acrylic resin, Examples thereof include polyester resins. The material resin is dissolved or dispersed in a solvent, an additive such as a pigment is added as appropriate, and it is applied by a method such as known roll coating or gravure coating and dried to have a thickness of about 0.1 to 30 μm, preferably Is a layer of 0.5 to 10 μm.
[0043]
(Reading of Timing Mark) Next, reading of the timing mark 101 will be described. FIG. 1C is a conceptual diagram in which a predetermined transfer portion 103 of the transfer foil 1 is transferred to a predetermined position of a transfer object using the transfer foil 1 of the present invention. First, the transfer foil 1 is unwound so that the timing mark 101 is guided to a position where it can be read by the sensor 107 and travels. The readable position is on the sensor reading line shown in a plan view in FIG. 1A, and the timing marks 101 whose lower portions are covered with the printing unit 33 are arranged in a predetermined positional relationship. Further, the timing mark 101 has a predetermined positional relationship with the transfer portion 103 to be transferred to the transfer target. That is, if the sensor 107 can accurately read the timing mark 101, the transfer unit 103 having a predetermined positional relationship with the timing mark 101 can be stopped at a predetermined position of the heated mold 109 of the transfer machine. The mold 109 is lowered to pressurize the thermal adhesive layer 26 of the transfer foil 1 and the transfer target. The thermal adhesive layer 26 is softened or melted to adhere to the transfer target. When the transfer foil 1 is peeled off, only the transfer substrate 21 is peeled off, and a transfer layer composed of a peeled layer / light diffraction layer / transparent reflective layer / thermal adhesive layer becomes the transfer portion 103 and is transferred to the transfer target.
[0044]
What is most important at the time of transfer is how accurately the sensor 107 can read the timing mark 101. Since the positional relationship between the timing mark 101 and the transfer portion 103 is formed at the same time, it is determined by the design and does not deviate beyond the tolerance. Since the timing mark 101 provided on the conventional optical diffraction layer 24 cannot be read by a normal inexpensive photosensor, a special sensor having a laser beam or a single wavelength light source must be used, and the detection light is diffracted light. Therefore, it is difficult to set the position of the sensor in order to adjust the angle of the diffracted light to a narrow angle range. Furthermore, the diffraction angle often varies depending on the item, and it is necessary to perform adjustment again for each item.
[0045]
Therefore, as a result of various studies, the present inventor has provided a printing layer 33 below the timing mark 101, and the printing layer 33 covers the timing mark 101, and as shown in FIG. Thus, it has been found that the conventional timing mark 101 can be read by a normal reading sensor 107 such as a bar code and transferred to a predetermined position on a transfer object in synchronization with the conventional timing mark 101. In this way, the contrast between the timing mark 101 and the strip-shaped printing unit 33 is increased, and can be easily read by the reading sensor 107 such as a normal barcode.
[0046]
(Reading accuracy) For example, by a known gravure printing method as the printing unit 33, a normal black gravure ink was used to form a printing layer having a thickness of 2 μm. The black ink is a black ink generally called by those skilled in the art. In principle, a complete black ink is not yet obtained, and is therefore called a black ink. As the timing mark 101, a mat image was taken by using a laser two-beam method. The transfer foil 1 was obtained by forming the timing mark 101 and the printing portion 33 and forming the other layers as described in the specification. When the transfer foil 1 was read by a sensor as shown in FIG. 1C, the signal amount (S) of the timing mark 101 was 91 and the signal amount (N) of the printing unit 33 was 25. The S / N ratio affecting the reading accuracy was 91/25 = 3.64.
On the other hand, a conventional type transfer foil 1 was obtained in the same manner except that no black ink printing layer was provided. When the timing mark of the transfer foil 1 was read by a sensor, the signal amount (S) of the timing mark 101 was 370, and the signal amount (N) of the other part was 320. The S / N ratio affecting reading accuracy was 370/320 = 1.16. Whereas the S / N ratio of the conventional type is 1.16, in the present invention, it can be remarkably increased to 3.64.
[0047]
In the conventional type, the heat bonding layer 26 is mainly buried in the light. The thermal adhesive layer 26 is subjected to a whitening treatment such as adding a pigment such as silica or brushing at the time of application in order to improve the foil cutting property at the time of transfer. For this reason, the light scattering property is particularly enhanced, and both the timing mark 101 and the printing unit 33 emit a remarkable signal amount, but the S / N ratio is small and there is no difference in the signal amount, resulting in being buried in light. It was. The print layer of the present invention is preferably black (close to black), but can be used if it is opaque and dark. The S / N ratio is about 2.0 or more, preferably 3.0 or more.
[0048]
In addition, when printing is performed repeatedly in accordance with the position of a pre-formed picture (registered by a person skilled in the art), the positional relationship (register) in both the flow direction and the width direction must be perfectly matched. However, in the present invention, it is a belt-like pattern, and it only needs to cover the timing mark 101, and rough registration only in the width direction is sufficient. In the present invention for printing in the form of a long web, registration in the width direction is extremely easy for those skilled in the art.
[0049]
【Example】
(Example 1) First, as a transfer substrate 21, a Lumirror F type (manufactured by Toray Industries Inc., a polyester film product name) having a thickness of 12 μm was used. To this one surface, release varnish 45-3 (manufactured by Showa Ink Co., Ltd., acrylic resin release ink product name) was diluted with a solvent so as to have a solid content of 10% by mass, and then dried by a roll coating method. The release layer 22 was formed by applying and drying to a thickness of 1 μm. On the surface of the release layer 22, Iupimer LZ065 (manufactured by Mitsubishi Chemical Co., Ltd., UV curable resin product name) is diluted with a solvent so as to have a solid content of 25% by mass, and after drying, the thickness after drying is 3 μm. The optical diffraction layer 24 was formed by coating and drying. A relief is formed by pressurizing (embossing) the stamper onto the surface of the light diffraction layer 24. Separately, a timing mark (ground glass) and a three-dimensional model are laser-beamed and a stamper copied by the 2P method is attached to the embossing roller of the copying apparatus from a master hologram that has been photographed. Was subjected to heat pressing (embossing) to form a relief consisting of a fine uneven pattern. Immediately after the shaping, the film was cured by irradiating ultraviolet rays having a wavelength of 200 to 400 nm with a high-pressure mercury lamp.
Zinc sulfide having a thickness of 400 nm was formed on the surface of the light diffraction layer 24 by a vacuum deposition method to form a transparent reflection layer 27. A normal gravure ink with carbon black as a colorant is printed by a gravure printing method so that the thickness after drying is 2 μm by covering the transparent reflective layer 27 as shown in FIG. Thus, the printing layer 33 was formed. The surface of the printing layer 33 is diluted with a solvent so that the vinyl chloride vinyl acetate copolymer is 25% by mass and 25% by mass of microsilica, and the thickness after drying is 2 μm by gravure printing. Then, it is applied to the entire surface and dried to form a heat bonding layer 26, and the transfer foil 1 having the light diffraction layer of the present invention (transfer base material / peeling layer / light diffraction layer / transparent reflection layer / printing layer / thermal bonding) Layer). When the transfer foil 1 was read by a sensor as shown in FIG. 1C, the signal amount (S) of the timing mark 101 was 91 and the signal amount (N) of the printing unit 33 was 25. The S / N ratio affecting reading accuracy was 91/25 = 3.64, which was favorable. Even ordinary photosensors could be read sufficiently.
[0050]
(Example 2) Transfer foil 1 having the light diffraction layer of the invention of Example 2 in the same manner as Example 1 except that a high-brightness ink reflective layer is provided between the transparent reflective layer 27 and the printing layer 33 ( Transfer substrate / peeling layer / light diffraction layer / transparent reflective layer / high-brightness ink reflective layer / printing layer / thermal adhesive layer) were obtained. The high-brightness ink reflection layer was formed 5 mm or more apart so as not to overlap with the timing mark 101 on which the light diffraction layer 24 was shaped. When the transfer foil 1 was read by a sensor as shown in FIG. 1C, the signal amount (S) of the timing mark 101 was 91 and the signal amount (N) of the printing unit 33 was 25. The S / N ratio affecting reading accuracy was 91/25 = 3.64, which was favorable.
[0051]
(Example 3) The present invention of Example 3 is the same as Example 1 except that SUZ600 (product name of UV curable resin, manufactured by The Inktec Co., Ltd.) is used as the optical diffraction layer 24 instead of Iupimer LZ065. The transfer foil 1 (transfer base material / peeling layer / light diffraction layer / transparent reflection layer / printing layer / thermal adhesive layer) having a light diffraction layer was obtained. When the transfer foil 1 was read by a sensor as shown in FIG. 1C, the signal amount (S) of the timing mark 101 was 91 and the signal amount (N) of the printing unit 33 was 25. The S / N ratio affecting the reading accuracy was 91/25 = 3.64.
[0052]
(Example 4) Transfer foil 1 having a light diffraction layer of the present invention of Example 4 (transfer base material / peeling layer / light diffraction) in the same manner as Example 1 except that gravure amber ink is used as the printing layer 33. Layer / transparent reflective layer / printing layer / thermal adhesive layer). When the transfer foil 1 was read by a sensor as shown in FIG. 1C, the signal amount (S) of the timing mark 101 was 91 and the signal amount (N) of the printing unit 33 was 45. The S / N ratio affecting the reading accuracy was 91/45 = 2.02. The image could be read with a normal photo sensor.
[0053]
(Comparative Example 1) A transfer foil (transfer base material / peeling layer / light diffraction layer / transparent reflective layer) having the conventional light diffraction layer of Comparative Example 1 in the same manner as in Example 1 except that the printing layer 33 is not provided. / Thermal adhesive layer). When the transfer foil 1 was read by a sensor as shown in FIG. 1C, the signal amount (S) of the timing mark 101 was 370, and the signal amount (N) of other portions was 320. The S / N ratio affecting reading accuracy was 370/320 = 1.16. I tried to read it with a normal photosensor, but I could read it 10 times and only once.
[0054]
【The invention's effect】
According to the transfer foil having the light diffraction layer of the present invention, even with the conventional timing mark 101, the contrast with the belt-like printing unit 33 is increased, and the reading sensor 107 such as a normal barcode can easily be used. Can be read. The transfer portion can be synchronized and transferred to a predetermined position on the transfer target.
In addition, the print layer is a strip-like pattern, and it is sufficient to consider only in the width direction. Since printing is performed in the form of a long web, registration in the width direction is extremely easy.
Furthermore, according to the transfer foil having the light diffraction layer of the present invention, the “metal reflection light diffraction image portion” and / or “colored metal reflection light diffraction image portion” and / or “transparent” are combined. The images of the “light diffraction image portion” and / or “colored transparent reflected light diffraction image portion” and / or “printed image portion” are arbitrary and can be arbitrarily combined. Thus, it has both excellent design and security. Furthermore, although it is easy to visually determine whether the image is true or false, the “metal reflection light diffraction image, transparent light diffraction image, and print image” constitute a complex and interlaced pattern, so it is extremely difficult to forge. Difficult and increases security.
[Brief description of the drawings]
FIG. 1 is a plan view, a side view, and a sectional view showing an embodiment of the present invention.
[Explanation of symbols]
1 Transfer foil
21 Transfer substrate
22 Release layer
23 Protective layer
24 Light diffraction layer
26 Thermal bonding layer
27 Transparent reflective layer
33 Printing Department
101 Timing mark
103 Transfer section
107 sensors
109 mold

Claims (2)

On one side of the substrate, at least a light diffraction layer, a transparent reflective layer, the transfer foil having an optical diffraction layer formed by the adhesive layer are sequentially laminated, it is provided an optical diffraction image and optical diffraction timing marks to the diffraction layer , light diffraction timing mark is in a positional relationship that correlates with the diffraction image, and so as to cover the timing marks, strip the opaque dark print layer to between the adhesive layer and the light diffraction layer The transfer foil having an optical diffraction layer, wherein the optical diffraction timing mark can be read by an optical reading sensor . When reading with the optical reading sensor, the S / N ratio is 2.0 or more, where S is the signal amount of the light diffraction timing mark and N is the signal amount of the printing unit. A transfer foil having the light diffraction layer according to claim 1.

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