JP3633316B2

JP3633316B2 - Anti-counterfeit paper

Info

Publication number: JP3633316B2
Application number: JP29792298A
Authority: JP
Inventors: 徹村上; 靖彦浅井; 慎一赤堀; 嘉彦福室
Original assignee: Tokushu Paper Manufacturing Co Ltd
Current assignee: Tokushu Paper Manufacturing Co Ltd
Priority date: 1998-10-20
Filing date: 1998-10-20
Publication date: 2005-03-30
Anticipated expiration: 2018-10-20
Also published as: JP2000129596A

Description

【０００１】
【発明の属する技術分野】
本発明は偽造防止用紙に関する。詳しくは有機溶剤を用いて改竄を試みてもその痕跡が視認できる偽造防止用紙に関する。
【０００２】
【従来の技術】
紙幣、商品券、パスポート、株券、小切手等は、不正に偽造されないように各種の偽造防止対策が施されている。偽造防止対策の考えの一つは、自然光や通常の照明下では偽造防止手段を視認することができず、特殊な機器を用いることで偽造防止手段を視認できるようにすることである。この考えに基づき、例えば、紫外線の照射によって各種色相に発色する蛍光染料や蛍光顔料を使用した偽造防止用紙や偽造防止印刷物、及びこれらに使用する材料についての提案がなされている。
【０００３】
例えば、特願平１−６８２９９号、他に提案されているように用紙の表面に蛍光顔料とベヒクルを主成分とするインキで文字や図柄を印刷した偽造防止印刷物は広く知られている。
【０００４】
また、特開昭５８−５４０９９号や、特公昭５６−１６３２８号には、用紙中に、蛍光染色した繊維を蛍光染色を施していない繊維と配合して抄造することを特徴とする偽造防止用紙の製造方法が提案されている。また、特開平６−１２８８０７号等には、酸化物系の蛍光顔料を紡糸時に添加した蛍光発色性繊維の製造方法が提案されている。
【０００５】
また、本出願人は先に特開平７−１６６１９８号において、紫外線の照射で蛍光色を発し、抄紙工程で基紙と接着可能な性能を有する細片を基紙の全面に遍在、若しくは筋状に偏在させた偽造防止用紙の提案を行った。
【０００６】
一方、色々な薬品を使用して改竄しても、改竄されたことが容易に判断できる偽造防止用紙も過去種々提案されている。例えば、特許第７８７７４号や特許第７７９６２号では、マンガンのフェロサイアナイドを用紙中に含ませ、金額欄に記載された文字をインク消しで消そうとすると褐色に変色する証券用紙の提案がある。
【０００７】
また、特許第１３６２８６号には、酸化剤により変色する物質とタンニン質と浸透剤を用紙に加工し、インク消しで改竄を試みると消滅することのない色が出る改竄防止用紙の提案がある。
【０００８】
また、特許１４１４４８３号には、水溶性のピレンスルホン酸金属塩系の反応性蛍光染料を用紙中に含有させ、インク消しや弱アルカリで改竄を試みると蛍光色を呈する安全紙の提案がある。
【０００９】
また、特開昭５７−２１６６０号には、消去可能なインクの溶剤を含む微小カプセルを用紙表面に含有させて、消しゴム等で改竄を試みてもその圧力でカプセルが開裂し、インクを紙層中に溶出浸透させて改竄の痕跡が残るようにした偽造防止用紙の提案がある。
【００１０】
また、特開昭６３−１８２４９６号には、ロイコ染料と、フェノール性物質、バインダーを主成分とする発色層を用紙表面に設け、有機溶剤で改竄を試みても溶剤の浸透でロイコ染料と、フェノール性物質が溶出し両者が化学反応し発色する改竄防止用紙の提案がある。
【００１１】
【発明が解決しようとする課題】
偽造防止手段はこのように種々知られているが、偽造を試みる者は後を絶たず、常に新規な偽造防止手段を採用した偽造防止用紙が求められているのが現状である。本発明はこのような背景でなされたものであって、本発明は、水不溶性でかつ有機溶剤可溶性の蛍光染料を使用して、これら従来提案された偽造防止用紙と全く異なる構成の、改竄の痕跡を視認できるタイプの新規な偽造防止用紙を開発することを課題とする。
【００１２】
【問題を解決するための手段】
本発明の要旨とするところは、水不溶性でかつ有機溶剤可溶性の、粒径が５０〜４００μｍである蛍光染料粒子が粒子の状態で用紙中に含まれており、有機溶剤による改竄の痕跡を紫外線の照射により視認できるようにしたことを特徴とする偽造防止用紙である。なお、本発明で用いる「通常の光源」とは、自然光、白熱電球、蛍光灯の光源を意味し、「蛍光染料」とは、紫外線の照射によって可視光域の特定の光を発する染料を意味し、増白効果を目的とした蛍光増白剤もこの範疇に含まれる。
【００１３】
【発明の実施の形態】
本発明で使用する蛍光染料粒子は、水不溶性でかつ有機溶剤可溶性であり、粒径が５０〜４００μｍであることが必要である。水溶性であると用紙製造中に該染料粒子が水に溶解してしまい本発明の目的を達成できなくなるからである。また、有機溶剤に可溶性でないと、溶剤で改竄を試みた場合に改竄された痕跡を視認できなくなるからである。また、その為には蛍光染料は粒子状で、かつその大きさは特定の範囲内にある必要があり、５０μｍ以下では有機溶剤が作用して蛍光染料粒子が溶解した際にその広がりが小さくて視認しにくく、４００μｍを越えると偽造防止用紙中で大きな凸部を形成してしまい、用紙としての取扱に支障が出るので好ましくない。
【００１４】
本発明で使用する蛍光染料粒子は、水不溶性でかつ有機溶剤に可溶性であればどのようなものでも使用できるが、クマリン系、オキサゾール系、ピラゾリン系等の、合成樹脂用に開発された蛍光増白用の蛍光染料が一例として挙げられる。これらの蛍光染料は、蛍光染料粒子そのものを容器に充填して見える色相は、通常の光源のもとでは無色であるが、紫外線の照射により青白色に発光する。この種の蛍光染料としては、染料メーカー各社で販売されているが一例を挙げると、（商品名「ＭｉｋａｗｈｉｔｅＡＴＮｃｏｎｃ．」、日本化薬（株）製造：通常の光源のもとで無色、紫外線の照射で赤味掛かった白色に発色）、（商品名「ＬｅｕｃｏｐｈｅｒＥＦ２Ｎ」、クラリアント（株）製造：通常の光源のもとで無色、紫外線の照射でわずかに青味の白色に発色）、（商品名「ＴＢＯ」、住友精化（株）製造：通常の光源のもとで無色、紫外線の照射で青白色に発色）、等々である。
【００１５】
また、本発明では、蛍光染料粒子そのものを容器に充填して見える色相が通常の光源のもとで有彩色で、紫外線の照射で各種色相に発光するアミノケトン系等の染料も使用できる。この種の蛍光染料も染料メーカー各社で販売されているが一例を挙げると、（商品名「ＹｅｌｌｏｗｆｌｕｏｒＧ」、住友化学工業（株）製造：通常の光源のもとで黄色、紫外線の照射で黄色に発色）、（商品名「ＫａｙａｓｅｔＦｌａｖｉｎｅＦＮ」、日本化薬（株）製造）：通常の光源のもとで黄色、紫外線の照射で黄色に発色）、（商品名「ＫａｙａｓｅｔＦｌａｖｉｎｅＦＧ」、日本化薬（株）製造：通常の光源のもとで黄色、紫外線の照射で黄色に発色）、（商品名「ＫａｙａｓｅｔＹｅｌｌｏｗＳＦ−Ｇ」、日本化薬（株）製造）：通常の光源のもとで黄色、紫外線の照射で黄色に発色）、（商品名「ＫａｙａｓｅｔＯｒａｎｇｅＳＦ−Ｒ」、日本化薬（株）製造：通常の光源のもとでオレンジ色、紫外線の照射でオレンジ色に発色）、（商品名「ＫａｙａｓｅｔＲｅｄＳＦ−Ｂ」、日本化薬（株）製造：通常の光源のもとで赤色、紫外線の照射で赤色に発色）、（商品名「ＫａｙａｓｅｔＲｅｄＳＦ−４Ｇ」、日本化薬（株）製造：通常の光源のもとで赤色、紫外線の照射で赤色に発色）、等々である。
【００１６】
本発明では、これらの水不溶性でかつ有機溶剤可溶性であり、粒径が５０〜４００μｍである蛍光染料を粒子状で用いる。粒子の大きさは、通常は２００μｍ以下であるが、本発明では該蛍光染料粒子が通常の光源のもとで有彩色である場合には、用紙に含まれていることを通常の光源のもとでは視認することができないようにするとそれだけ偽造防止効果を高めることができる。但し、後に述べるように３層抄き合わせで内層に該染料粒子を存在させ、外層に存在させない構成の偽造防止用紙の場合には、外層により該染料粒子が覆われるので、４００μｍという比較的大きな粒径の染料粒子を使用することができる。水不溶性でかつ有機溶剤可溶性であり、粒径が５０〜４００μｍである蛍光染料粒子の用紙に対する添加量は、染料の種類や偽造防止用紙としての用途等によって変化するが通常は、０．００１〜０．５重量％の範囲である。
【００１７】
本発明において、水不溶性でかつ有機溶剤可溶性であり、粒径が５０〜４００μｍである蛍光染料粒子を用紙中に含ませる方法としては、どのような方法を採用してもよい。以下、例を挙げて説明する。なお、本発明ではこれらの蛍光染料粒子を単独で用いても２種類以上を併用してもよい。
製造例１
用紙を抄造するスラリーの調製後に水不溶性でかつ有機溶剤可溶性であり、粒径が５０〜４００μｍである蛍光染料粒子をスラリーに添加して抄紙する方法
本発明の偽造防止用紙の製造に際しては、通常、針葉樹晒クラフトパルプ（ＮＢＫＰ）、広葉樹晒クラフトパルプ（ＬＢＫＰ）、針葉樹晒サルファイトパルプ（ＮＢＳＰ）、サーモメカニカルパルプ（ＴＭＰ）等の製紙用パルプを主体としたスラリーを調製し、これに各種内添填料、乾燥紙力増強剤、サイズ剤、定着剤、歩留り向上剤、濾水性向上剤、消泡剤、染料、着色顔料等の製紙用副資材を適宜併用し、通常フリーネス５５０〜２５０ｍｌＣ．Ｓ．Ｆ．にスラリーを調製し、前記した水不溶性でかつ有機溶剤可溶性であり、粒径が５０〜４００μｍである蛍光染料粒子を添加して円網抄紙機や、長網抄紙機等の周知の抄紙機を使用して抄紙する。
【００１８】
市販の上質紙は、水溶性の４，４´−ジアミノスチルベンジスルホン酸誘導体、スチルベントリアジニル誘導体、４，４´−ビストリアジニルアミノスチルベン、２，２´−ジスルホン酸誘導体、等の水溶性のスチルベン系蛍光増白剤等をパルプに定着させて製造することで用紙の見かけの白さを向上させている。この場合、これらの蛍光増白剤は用紙を構成するセルロース繊維表面を万遍なく覆っている状態で分布している。蛍光増白剤も紫外線の照射で青白色や青紫色等に発光する性質を持っているのでこの上質紙は紫外線の照射により、全面が青白色や青紫色等に発光する。
【００１９】
本発明においては、水不溶性でかつ有機溶剤可溶性の蛍光染料は、抄紙工程の水の作用によっても溶出しないので粒子の状態で用紙中に存在する。該蛍光染料の粒子径を適当な大きさにすることによって、通常の照明下ではその存在が視認できず、紫外線の照射により発光しその存在を視認できるようにさせることができる。この理由は、通常の照明下では、粒子径が小さいために視認できないが、紫外線の照射では自ら強い光を発し視認できるためと思われる。本発明の偽造防止用紙においては、水不溶性でかつ有機溶剤可溶性の蛍光染料粒子を紫外線の照射で視認できるようにさせるためには、前記した水溶性の蛍光増白剤は使用しないか、使用しても本発明の効果を阻害しない範囲の少量に留めることが必要である。
【００２０】
製造例２
用紙を抄造するスラリーを抄紙機に流送する途中に水不溶性でかつ有機溶剤可溶性であり、粒径が５０〜４００μｍである蛍光染料粒子の水懸濁液をポンプ等を使用して添加する方法
製造例１の水不溶性でかつ有機溶剤可溶性であり、粒径が５０〜４００μｍである蛍光染料粒子を添加しないスラリーを使用して円網抄紙機や、長網抄紙機等の周知の抄紙機を使用して抄紙する際に、長網抄紙機のフローボックス内や、円網抄紙機のバット内に水不溶性でかつ有機溶剤可溶性であり、粒径が５０〜４００μｍである蛍光染料粒子を水に懸濁した状態でポンプ等を使用して添加して抄紙する。
【００２１】
本発明においては、前記偽造防止用紙が少なくとも３層以上の多層抄き合わせで形成されており、かつ内層のみに前記水不溶性でかつ有機溶剤可溶性であり、粒径が５０〜４００μｍである蛍光染料粒子が含まれていることが好ましい。この理由は水不溶性でかつ有機溶剤可溶性であり、粒径が５０〜４００μｍである蛍光染料粒子が用紙表面に露出している状態で存在していると、該染料粒子自身には自着性が無いために、グラビア印刷の場合には問題はないがオフセット印刷時に該染料粒子が脱落する問題等を起こしやすくなるためである。３層以上の多層抄き合わせの用紙を製造するには、例えば３槽式の円網抄紙機を使用して３層抄きの用紙を抄造する際に、内層（この場合は中央の層）のみに前記した方法を使用して水不溶性でかつ有機溶剤可溶性であり、粒径が５０〜４００μｍである蛍光染料粒子を存在させればよい。この構成の偽造防止用紙は有機溶剤の浸透により内層に含まれる該蛍光染料粒子が溶解し、毛細管現象により用紙表面に拡散するので、内層に該蛍光染料粒子が含まれていても本発明の目的を阻害することが無い。
【００２２】
製造例３
長網抄紙機で用紙を抄造する際に抄紙網上の湿紙に水不溶性でかつ有機溶剤可溶性であり、粒径が５０〜４００μｍである蛍光染料粒子を振りかける方法
製造例１の水不溶性でかつ有機溶剤可溶性であり、粒径が５０〜４００μｍである固着されていない蛍光染料粒子を添加しないスラリーを使用して、長網抄紙機を使用して用紙を抄紙する際に、長網抄紙機の抄紙網上の湿紙に水不溶性でかつ有機溶剤可溶性であり、粒径が５０〜４００μｍである蛍光染料粒子を全面または筋状に振り掛け装置等を使用して振り掛け、後は常法に従って抄紙する。
【００２３】
製造例４
長網抄紙機で用紙を抄造する際に抄紙網上の湿紙に水不溶性でかつ有機溶剤可溶性であり、粒径が５０〜４００μｍである蛍光染料粒子の水懸濁液を振りかける方法
製造例１の水不溶性でかつ有機溶剤可溶性であり、粒径が５０〜４００μｍである蛍光染料粒子を添加しないスラリーを使用して、長網抄紙機を使用して用紙を抄紙する際に、長網抄紙機の抄紙網上の湿紙に水不溶性でかつ有機溶剤可溶性であり、粒径が５０〜４００μｍである蛍光染料粒子を水に懸濁させ全面または筋状に振り掛け装置やノズル噴射装置等を使用して振り掛け、後は常法に従って抄紙する。
【００２４】
製造例５
サイズプレス液等に水不溶性でかつ有機溶剤可溶性であり、粒径が５０〜４００μｍである蛍光染料粒子を併用する方法
製造例１の水不溶性でかつ有機溶剤可溶性であり、粒径が５０〜４００μｍである蛍光染料粒子を添加しないスラリーを使用して、長網抄紙機を使用して用紙を抄紙する際に、サイズプレス装置を使用して、変成澱粉、ポリアクリルアマイド、ポリビニルアルコール等のサイズプレス液に水不溶性でかつ有機溶剤可溶性であり、粒径が５０〜４００μｍである蛍光染料粒子を懸濁させ湿紙表面に塗工し、後は常法に従って抄紙する。
【００２５】
製造例６
エアナイフコーター等のコーターを使用して水系の塗料を塗工する際に水不溶性でかつ有機溶剤可溶性であり、粒径が５０〜４００μｍである蛍光染料粒子を併用する方法
製造例１の水不溶性でかつ有機溶剤可溶性であり、粒径が５０〜４００μｍである蛍光染料粒子を添加しないスラリーを使用して、長網抄紙機や円網抄紙機を使用して抄紙後に、アート紙やコート紙製造用塗工液の中に水不溶性でかつ有機溶剤可溶性であり、粒径が５０〜４００μｍである蛍光染料粒子を添加して、エアナイフコーター、ブレードコーター等の塗工機を使用して用紙を製造する。
【００２６】
製造例７
用紙に印刷を施す際に水性インキに水系の塗料を塗工する際に、水不溶性でかつ有機溶剤可溶性であり、粒径が５０〜４００μｍである蛍光染料粒子を添加する方法
水性インキ中に水不溶性でかつ有機溶剤可溶性であり、粒径が５０〜４００μｍである蛍光染料粒子を添加し、印刷機を使用して用紙に所定の文字や模様を印刷する。この際使用する用紙は前述した理由により、蛍光増白剤を使用しない用紙を用いることが必要である。印刷は抄紙機で用紙を抄造中に行ってもよいし（フレキソ印刷機等を使用してのオンマシン印刷）、用紙の抄造後にグラビア印刷機等を使用して行ってもよい（オフマシン印刷）。例えば「ＶＯＩＤ」の文字を印刷しておけば、有機溶剤で改竄を試みると「ＶＯＩＤ」の文字が浮き出るようにさせることができ、この文字は紫外線の照射で視認できる。
【００２７】
本発明に置いては、前述した各種の方法のうち水不溶性でかつ有機溶剤可溶性であり、粒径が５０〜４００μｍである蛍光染料粒子の歩留まりがよいこと（スラリーに添加すると該蛍光染料粒子の粒子径が小さいので抄紙網から染料粒子が流出し易くなる）と、抄紙機等を汚染しないので、サイズプレス液等に水不溶性でかつ有機溶剤可溶性であり、粒径が５０〜４００μｍでありかつバインダーで固着されていない蛍光染料粒子を併用する方法や、エアナイフコーター等のコーターを使用して水系の塗料を塗工する際に該蛍光染料粒子を併用する方法、用紙に印刷を施す際に水性インキに水不溶性でかつ有機溶剤可溶性であり、粒径が５０〜４００μｍである蛍光染料粒子を添加する方法を採用することが好ましい。
【００２８】
以下実施例を述べるが、重量部、ｇ／ｍ^２は固形分換算の値を意味する。
【実施例】
実施例１
ＮＢＫＰ２０重量部、ＬＢＫＰ８０重量部を３５０ｍｌＣ．Ｓ．Ｆ．に叩解し、これに白土１０重量部、紙力増強剤（商品名「ポリストロン１９１」、荒川化学工業（株）製造）０．３重量部、サイズ剤（商品名「サイズパインＥ」、荒川化学工業（株）製造）１．０重量部、硫酸バンドを適量加えスラリーを調製した。このスラリーに、平均粒径が約５０μｍの水不溶性でかつ有機溶剤可溶性の蛍光染料粒子（商品名「ＫａｙａｓｅｔＹｅｌｌｏｗＳＦ−Ｇ」、日本化薬（株）製造）を０．０８重量部添加して分散させた。このスラリーを使用して常法に従い長網抄紙機で坪量１００ｇ／ｍ^２の偽造防止用紙を抄造した。この際乾燥ゾーンの途中に設置されているサイズプレス装置でポリビニルアルコールの０．２重量％水溶液を塗工した。得られた偽造防止用紙は蛍光灯照明下で観察しても該蛍光染料粒子の存在が視認できなかったが、暗室内で紫外線（ブラックライト）を照射すると黄色に発色する微細な蛍光染料粒子を視認できた。
【００２９】
実施例２
ＮＢＫＰ２０重量部、ＬＢＫＰ８０重量部を３５０ｍｌＣ．Ｓ．Ｆ．に叩解し、これに白土１０重量部、紙力増強剤（商品名「ポリストロン１９１」、荒川化学工業（株）製造）０．３重量部、サイズ剤（商品名「サイズパインＥ」、荒川化学工業（株）製造）１．０重量部、硫酸バンドを適量加えスラリーを調製した。このスラリーを使用して常法に従い長網抄紙機で坪量１００ｇ／ｍ^２の用紙を抄造中に乾燥ゾーンの途中に設置されているサイズプレス装置でポリビニルアルコールの０．２重量％水溶液に、平均粒径が約２５０μｍの水不溶性でかつ有機溶剤可溶性の蛍光染料粒子（商品名「ＫａｙａｓｅｔＲｅｄＳＦ−４Ｇ」、日本化薬（株）製造）を０．０４重量％分散させた液を塗工し、常法に従い乾燥させ偽造防止用紙を製造した。得られた偽造防止用紙は蛍光灯照明下で観察しても該蛍光染料粒子の存在が視認できなかったが、暗室内で紫外線（ブラックライト）を照射すると赤色に発色する微細な蛍光染料粒子を視認できた。
【００３０】
実施例３
ＮＢＫＰ２０重量部、ＬＢＫＰ８０重量部を３５０ｍｌＣ．Ｓ．Ｆ．に叩解し、これに白土１０重量部、紙力増強剤（商品名「ポリストロン１９１」、荒川化学工業（株）製造）０．３重量部、サイズ剤（商品名「サイズパインＥ」、荒川化学工業（株）製造）１．０重量部、硫酸バンドを適量加えスラリーを調製した。このスラリーを使用して常法に従い長網抄紙機で坪量１００ｇ／ｍ^２の原紙を抄造した。
次いで、カオリン（商品名「ＵＷ−９０」、エンゲルハード（株）製造）７５重量部、炭酸カルシウム（商品名「ＴＰ−２２２ＨＳ」、奥多摩工業（株）製造）２５重量部、バインダーとして澱粉（商品名「ＭＣ−３０００」、敷島スターチ（株）製造）６重量部、ＳＢＲラテックス（商品名「ニポールＬＸ４０７Ｃ」、日本ゼオン（株）製造）１２重量部を主体とする水性塗料（濃度３５重量％）を常法に従い調製し、これに、平均粒径が約１５０μｍの水不溶性でかつ有機溶剤可溶性の蛍光染料粒子（商品名「ＴＢＯ」、住友精化（株）製造）を塗料固形分に対して０．０６重量％添加した。この塗料を前記原紙の両面に１５ｇ／ｍ^２ずつエアナイフコーターを使用して塗工して乾燥後、スーパーキャレンダー処理して偽造防止用紙を製造した。得られた偽造防止用紙は蛍光灯照明下で観察しても該蛍光染料粒子の存在が視認できなかったが、暗室内で紫外線（ブラックライト）を照射すると青白色に発色する微細な蛍光染料粒子を視認できた。
【００３１】
実施例４
実施例３と同一の水性塗料（濃度３５重量％）を調製し、これに、水不溶性でかつ有機溶剤可溶性の蛍光染料粒子（商品名「ＫａｙａｓｅｔＹｅｌｌｏｗＳＦ−Ｇ」、日本化薬（株）製造）、及び（商品名「ＴＢＯ」、住友精化（株）製造）、及び（商品名「ＫａｙａｓｅｔＲｅｄＳＦ−４Ｇ」、日本化薬（株）製造）を塗料固形分に対して各々０．０３重量％添加した。この塗料を前記原紙の両面に１５ｇ／ｍ^２ずつエアナイフコーターを使用して塗工して乾燥後、スーパーキャレンダー処理して偽造防止用紙を製造した。得られた偽造防止用紙は蛍光灯照明下で観察しても該蛍光染料粒子の存在が視認できなかったが、暗室内で紫外線（ブラックライト）を照射すると黄色、赤色、青白色に発色する微細な蛍光染料粒子を視認できた。
【００３２】
比較例
スチルベン系の蛍光増白剤（水溶性で有機溶剤に不溶性）を内添した通常の上質紙を比較例として挙げる。
【００３３】
代表的な各種有機溶剤を各実施例で得られた偽造防止用紙と比較例の上質紙の表面に滴下し、有機溶剤が蒸発してから滴下したところを室内の蛍光灯照明下、及び室内の蛍光灯照明下で紫外線（ブラックライト）を照射して観察した結果を表１に示す。なお、この結果は自然光下や白熱電球による照明下でも同一の結果が得られることを確認した。
【００３４】
【表１】

【００３５】
実施例１と実施例２で使用した水不溶性でかつ有機溶剤可溶性の蛍光染料粒子そのものが多量に集まると、通常の照明下で着色して見えるが、実施例のように用紙中に微量に分布させるとその存在が通常の照明下では視認できなくなる（極めて多量に使用すると、その染料独特の色相が淡く見えるようになる）。これは人間の目の解像度の限界を超えた微細な染料粒子が少量存在するためによる。しかしこれら実施例で得られた偽造防止用紙に暗室で紫外線を照射するとその染料特有の蛍光色を発するようになり、微細な粒子として視認できる。なお、実施例３で使用した水不溶性でかつ有機溶剤可溶性の蛍光染料粒子そのものが多量に集まっても無色であるが、実施例３の偽造防止用紙に、暗室で紫外線を照射するとその染料特有の蛍光色を発するようになり、微細な粒子として視認できる。
【００３６】
これら実施例で得られた偽造防止用紙の表面に各種有機溶剤を滴下すると、有機溶剤の作用で用紙に含まれている染料が溶出して、毛細管現象で周囲に拡散する。溶剤が蒸発した後に滴下面を蛍光灯照明下で観察すると、実施例１と２では、石油エーテルの滴下の場合を除き用いた染料に起因する色相が視認できた。実施例３では用いた染料が無色であるので滴下面が変化が無いように見えた。実施例４では、斑点状で異なった色相が視認できた。
【００３７】
さらにこれら用紙を蛍光灯照明下で紫外線（ブラックライト）を照射すると、実施例１，２は石油エーテルの滴下の場合を除き、滴下面に相当する部分が各染料独特の色相に蛍光発色して見えた。
【００３８】
なお、参考として有機溶剤の代わりに、水を滴下した結果を示したがいずれの場合も何ら変化がなかった。また、比較例の上質紙の場合も何ら変化は認められなかった。
【００３９】
以上は蛍光灯照明下、及び蛍光灯照明下で紫外線を照射した結果であるが、白熱電球照明下や自然光下、及び白熱電球照明下や自然光下で紫外線を照射した場合でも同一の結果が得られることを確認した。
なお、水不溶性でかつ有機溶剤可溶性の蛍光染料は以上述べた他にも種々あり、有機溶剤への溶解性も異なっているので、偽造防止用紙に求められる性能に応じて種々使い分ければよい。
【００４０】
【発明の効果】
本発明の偽造防止用紙は以上述べたように構成され、下記に述べるような顕著な効果を有する。
１）パスポート、トラベラーズチェック、小切手、手形、身分証明書等は油溶性のインキを使用したボールペンで文字を記載することが多いが、本発明の偽造防止用紙はこのようなタイプの偽造防止印刷物の用途に好適に利用することができ、有機溶剤による改竄の痕跡を明るい室内でも紫外線の照射により容易に視認できるし、発色することで改竄者が改竄を諦める効果もある。
２）また、スクライブ方式のくじ用紙（当たりはずれを印刷し、この印刷面にアルミ粉印刷を施して隠蔽させ、購入者がアルミ粉印刷部分を爪等でこすって除去して当落を判定する方式）に好適に利用できる。即ち、くじが販売される前の流通過程で、有機溶剤を使用してアルミ粉印刷部を除去して当落を読みとり、当たりくじのみを盗み、はずれくじに再びアルミ粉印刷を行うような犯罪に対しても防止効果が大きい。
３）また、水不溶性でかつ有機溶剤可溶性の蛍光染料は種類が豊富であるので、例えばロットごとに該蛍光染料の種類や添加量を変化させて用紙に添加しておき、必要が生じたらどのロットの製品であるのか判断を下すことができる用途にも本発明の偽造防止用紙は好適に使用できる。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to anti-counterfeit paper. Specifically, the present invention relates to a forgery-preventing paper in which traces can be visually recognized even when attempting to tamper with an organic solvent.
[0002]
[Prior art]
Bills, gift certificates, passports, stock certificates, checks, and the like have various anti-counterfeiting measures to prevent them from being counterfeited. One idea of anti-counterfeiting measures is that the anti-counterfeiting means cannot be visually recognized under natural light or normal lighting, and the anti-counterfeiting means can be visually recognized by using a special device. Based on this idea, for example, proposals have been made on anti-counterfeit paper and anti-counterfeit printed matter using fluorescent dyes and fluorescent pigments that develop colors in various hues when irradiated with ultraviolet rays, and materials used for these.
[0003]
For example, as disclosed in Japanese Patent Application No. 1-68299 and others, anti-counterfeit printed matter in which characters and designs are printed on a surface of paper with ink mainly composed of a fluorescent pigment and a vehicle is widely known.
[0004]
JP-A-58-54099 and JP-B-56-16328 disclose anti-counterfeit paper characterized in that paper is blended with a fiber that is not fluorescently dyed to make paper. The manufacturing method of this is proposed. Japanese Patent Laid-Open No. 6-128807 proposes a method for producing a fluorescent color-forming fiber in which an oxide-based fluorescent pigment is added during spinning.
[0005]
In addition, the applicant previously disclosed in Japanese Patent Application Laid-Open No. 7-166198, a strip that emits a fluorescent color when irradiated with ultraviolet rays and has a performance capable of adhering to the base paper in the paper making process is ubiquitous on the entire surface of the base paper. We proposed anti-counterfeit paper that was unevenly distributed.
[0006]
On the other hand, various anti-counterfeit papers have been proposed in the past that can be easily determined to be falsified even if they are falsified using various chemicals. For example, Japanese Patent No. 78774 and Patent No. 77962 propose a security paper that contains manganese ferrothiayanide in the paper and turns brown when the characters listed in the amount column are erased by ink erasing. is there.
[0007]
Japanese Patent No. 136286 proposes a falsification-preventing paper in which a substance that changes color by an oxidizing agent, a tannin, and a penetrating agent are processed into paper, and a color that does not disappear when an attempt is made to erase with ink erasing.
[0008]
Japanese Patent No. 1414483 also proposes a safety paper that exhibits a fluorescent color when a water-soluble pyrenesulfonic acid metal salt-based reactive fluorescent dye is contained in the paper and the ink is erased or attempts to falsify with weak alkali.
[0009]
Japanese Patent Laid-Open No. 57-21660 discloses that a microcapsule containing a solvent for erasable ink is contained on the surface of the paper, and even if an attempt is made to tamper with an eraser or the like, the capsule is cleaved by the pressure, and the ink is separated from the paper layer. There is a proposal of anti-counterfeit paper that is eluted and penetrated to leave traces of tampering.
[0010]
Japanese Patent Laid-Open No. 63-182496 discloses that a leuco dye, a phenolic substance, and a coloring layer mainly composed of a binder are provided on the surface of the paper. There is a proposal for a falsification-preventing paper in which phenolic substances are eluted and both chemically react to develop color.
[0011]
[Problems to be solved by the invention]
Various anti-counterfeiting means are known in this way, but the current situation is that people who try to forge counterfeit constantly, and anti-counterfeit papers that always employ new anti-counterfeiting means are required. The present invention has been made in such a background, and the present invention uses a fluorescent dye that is water-insoluble and organic solvent-soluble and has a configuration completely different from those of the conventionally proposed anti-counterfeit paper. It is an object to develop a new anti-counterfeit paper of a type in which traces can be visually recognized.
[0012]
[Means for solving problems]
It is an aspect of the present invention, the water-insoluble and organic solvent-soluble, is contained in the paper by particle size 50~400μm der Ru fluorescent dye particles in particle state, traces of tampering with an organic solvent Is an anti-counterfeit paper characterized in that it can be visually recognized by irradiation with ultraviolet rays. The “ordinary light source” used in the present invention means natural light, an incandescent bulb, and a fluorescent light source, and the “fluorescent dye” means a dye that emits specific light in the visible light region when irradiated with ultraviolet rays. However, fluorescent whitening agents aimed at whitening effects are also included in this category.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Fluorescent dye particles used in the present invention are water insoluble and organic solvent-soluble, the particle size is needed and 50~400μm der Turkey. This is because the water-soluble dye particles dissolve in water during paper manufacture and cannot achieve the object of the present invention. In addition, if it is not soluble in an organic solvent, it is not possible to visually recognize the tampered trace when tampering with the solvent is attempted. For this purpose, the fluorescent dye must be in the form of particles and the size thereof must be within a specific range. When the fluorescent dye particles are dissolved by the action of an organic solvent below 50 μm, the spread is small. viewing difficult, will form a large convex portion in the anti-falsification paper exceeds 400 [mu] m, have Na preferable because detrimental to handling as paper.
[0014]
The fluorescent dye particles used in the present invention may be any particles that are insoluble in water and soluble in organic solvents. However, the fluorescent dye particles developed for synthetic resins such as coumarins, oxazoles, and pyrazolines may be used. An example is a fluorescent dye for white. These fluorescent dyes appear to be filled with fluorescent dye particles themselves in a container, but are colorless under normal light sources, but emit blue-white light when irradiated with ultraviolet rays. This type of fluorescent dye is sold by various dye manufacturers. For example, (Mikawhite ATN conc., Manufactured by Nippon Kayaku Co., Ltd.) (Colored to white that was reddish by irradiation of), (trade name “Leucopher EF 2N”, manufactured by Clariant Co., Ltd .: colorless under normal light source, colored to bluish white by UV irradiation), (Trade name “TBO”, manufactured by Sumitomo Seika Co., Ltd .: colorless under normal light source, blue-white color by ultraviolet irradiation), and so on.
[0015]
In the present invention, aminoketone-based dyes that emit a chromatic color under a normal light source and emit various colors when irradiated with ultraviolet rays can be used. This type of fluorescent dye is also sold by various dye manufacturers. For example, (trade name “Yellowfluor G”, manufactured by Sumitomo Chemical Co., Ltd .: yellow under normal light source, yellow under ultraviolet light irradiation. Color development), (trade name “Kayaset Flavine FN”, manufactured by Nippon Kayaku Co., Ltd.): yellow under normal light source, yellow color by UV irradiation), (trade name “Kayaset Flavine FG”, Japan Kayaku Co., Ltd. manufacture: yellow under normal light source, yellow color under UV irradiation) (trade name “Kayaset Yellow SF-G”, manufactured by Nippon Kayaku Co., Ltd.): normal light source And yellow color when irradiated with ultraviolet rays), (trade name “Kayaset Orange SF-R”, manufactured by Nippon Kayaku Co., Ltd .: orange under normal light source, oren when irradiated with ultraviolet rays Color development), (trade name “Kayaset Red SF-B”, manufactured by Nippon Kayaku Co., Ltd .: red under normal light source, red development by UV irradiation), (trade name “Kayaset Red SF- 4G ", manufactured by Nippon Kayaku Co., Ltd .: red under normal light source, red when irradiated with ultraviolet light), and so on.
[0016]
In the present invention, it is these water-insoluble and organic solvent-soluble, the particle size is used 50~400μm der Ru fluorescent dye in the form of particles. The size of the particles is usually 200 μm or less. However, in the present invention, when the fluorescent dye particles are chromatic under a normal light source, the size of the normal light source is determined to be included in the paper. Ru can be enhanced correspondingly forgery prevention effect by not visible in the the. However , as will be described later, in the case of anti-counterfeit paper having a structure in which the dye particles are present in the inner layer and not in the outer layer in the three-layer assembling, the dye particles are covered by the outer layer, so that the relatively large size of 400 μm. Dye particles of particle size can be used. A water-insoluble and organic solvent-soluble, the addition amount the particle size is on a sheet of 50~400μm der Ru fluorescent dye particles generally varies depending on the application such as a dye type and anti-falsification paper, 0. It is in the range of 001 to 0.5% by weight.
[0017]
In the present invention, a water-insoluble and organic solvent-soluble, as a method to include a fluorescent dye particles particle sizes of 50~400μm in paper, it may be employed any method. Hereinafter, an example will be described. In the present invention, these fluorescent dye particles may be used alone or in combination of two or more.
Production Example 1
A method for making paper by adding fluorescent dye particles having a particle size of 50 to 400 [mu] m, which is water-insoluble and organic solvent-soluble, after the preparation of the slurry for paper making to manufacture the anti-counterfeit paper of the present invention In that case, usually a slurry mainly composed of paper pulp such as softwood bleached kraft pulp (NBKP), hardwood bleached kraft pulp (LBKP), softwood bleached sulfite pulp (NBSP), thermomechanical pulp (TMP), and the like, Various internal additives, dry paper strength enhancers, sizing agents, fixing agents, yield improvers, drainage improvers, antifoaming agents, dyes, coloring pigments, and other papermaking auxiliary materials are used in combination as appropriate. ~ 250 ml C.I. S. F. A known paper machine such as a circular net paper machine or a long net paper machine is prepared by adding a fluorescent dye particle having a particle size of 50 to 400 μm by preparing a slurry and adding water-insoluble and organic solvent-soluble particles as described above. Use to make paper.
[0018]
Commercially available high-quality paper is water-soluble such as water-soluble 4,4′-diaminostilbene disulfonic acid derivatives, stilventriazinyl derivatives, 4,4′-bistriazinylaminostilbene, 2,2′-disulfonic acid derivatives, etc. The apparent whiteness of the paper is improved by fixing the stilbene fluorescent whitening agent and the like to the pulp. In this case, these fluorescent brighteners are distributed in a state where the cellulose fiber surfaces constituting the paper are uniformly covered. Since the fluorescent whitening agent also has a property of emitting blue white or blue purple when irradiated with ultraviolet rays, the high-quality paper emits blue white or blue purple when irradiated with ultraviolet rays.
[0019]
In the present invention, the water-insoluble and organic solvent-soluble fluorescent dye does not elute due to the action of water in the paper making process, and therefore exists in the form of particles in the paper. By setting the particle size of the fluorescent dye to an appropriate size, the presence of the fluorescent dye cannot be visually recognized under normal illumination, and the light can be emitted by irradiation with ultraviolet rays so that the presence can be visually recognized. The reason for this is considered to be that, under normal illumination, the particle diameter is small and thus cannot be visually recognized, but when irradiated with ultraviolet rays, strong light can be emitted and visually recognized. In the anti-counterfeit paper of the present invention, the above-mentioned water-soluble fluorescent whitening agent is not used or used in order to make water-insoluble and organic solvent-soluble fluorescent dye particles visible by ultraviolet irradiation. However, it is necessary to keep it in a small amount that does not impair the effects of the present invention.
[0020]
Production Example 2
A method of adding a water suspension of fluorescent dye particles having a particle diameter of 50 to 400 μm using a pump or the like while water-insoluble and organic solvent-soluble slurry is fed to a paper machine. A well-known example of a circular net paper machine, a long net paper machine, etc., using a slurry which is water-insoluble and organic solvent-soluble in Production Example 1 and does not contain fluorescent dye particles having a particle size of 50 to 400 μm. Fluorescent dye that is water-insoluble and organic-solvent-soluble and has a particle size of 50 to 400 μm in the flow box of a long net paper machine or in the vat of a circular net paper machine. Add particles using a pump or the like while suspended in water to make paper.
[0021]
Fluorescent dyes in the present invention, the anti-falsification paper is formed by at least three or more layers paper making alignment, and a the water insoluble and organic solvent-soluble only in the inner layer, the particle size is 50~400μm Preferably, particles are included. This is because water-insoluble and organic solvent-soluble dye particles having a particle size of 50 to 400 μm are present on the surface of the paper so that the dye particles themselves are self-adhesive. This is because there is no problem in the case of gravure printing, but the problem that the dye particles fall off during offset printing is likely to occur. To manufacture multi-layered paper with 3 or more layers, the inner layer (in this case, the middle layer) is used when making a 3-layer paper using, for example, a 3-tank paper machine. Only the fluorescent dye particles which are water-insoluble and organic solvent-soluble and have a particle diameter of 50 to 400 μm may be present using the above-described method. The anti-counterfeit paper having this configuration dissolves the fluorescent dye particles contained in the inner layer by permeation of the organic solvent and diffuses to the paper surface by capillary action. Therefore, even if the fluorescent dye particles are contained in the inner layer, the object of the present invention Is not disturbed.
[0022]
Production Example 3
Method of sprinkling fluorescent dye particles that are water-insoluble and organic solvent-soluble and have a particle size of 50 to 400 [mu] m in wet paper on a paper net when paper is made with a long paper machine a water-insoluble and organic solvent-soluble, when the particle size using a slurry without addition of fluorescent dye particles that are not fixed is 50 to 400 [mu] m, for the paper sheet by using the Fourdrinier paper machine, the length a water-insoluble and organic solvent-soluble wet paper on the paper making net net paper machine, sprinkled fluorescent dye particles particle sizes of 50~400μm using all or streaked sprinkling device, after the normal Make paper according to the law.
[0023]
Production Example 4
A method of sprinkling an aqueous suspension of fluorescent dye particles having a particle size of 50 to 400 μm that is water-insoluble and organic solvent-soluble in wet paper on a papermaking net when paper is made with a long paper machine <br / > When making paper using a long net paper machine using the slurry of Production Example 1 that is water-insoluble and organic solvent-soluble and that does not contain fluorescent dye particles having a particle size of 50 to 400 μm, Fluorescent dye particles, which are water-insoluble and organic solvent-soluble and have a particle size of 50 to 400 μm, are suspended in water on a wet paper on a paper net of a long net paper machine, and are sprinkled on the entire surface or in a streak shape and a nozzle injection device Sprinkle using etc., and then make paper according to the usual method.
[0024]
Production Example 5
Method of using fluorescent dye particles that are water-insoluble and organic solvent-soluble in a size press solution or the like and have a particle size of 50 to 400 μm The water-insoluble and organic solvent-soluble particle size of Production Example 1 There using a slurry without addition of fluorescent dye particles is 50 to 400 [mu] m, in the paper making process the paper using a Fourdrinier, using a size press apparatus, modified starch, polyacrylamide, polyvinyl alcohol a water-insoluble and organic solvent-soluble in the size press solution and the like, particle size was applied to the fluorescent wet paper surface dye particles are suspended is 50 to 400 [mu] m, after the papermaking in a conventional manner.
[0025]
Production Example 6
Method of using together fluorescent dye particles that are water-insoluble and organic solvent-soluble and have a particle size of 50 to 400 [mu] m when applying a water-based paint using a coater such as an air knife coater Production Example 1 Using water-insoluble and organic solvent-soluble slurry without adding fluorescent dye particles having a particle diameter of 50 to 400 μm, and using art paper or circular net paper machine, a water-insoluble and organic solvent soluble in coated paper production coating liquid for a particle size by adding a fluorescent dye particles is 50 to 400 [mu] m, an air knife coater, using a coating machine such as a blade coater Manufacture paper.
[0026]
Production Example 7
Method of adding fluorescent dye particles that are water-insoluble and organic solvent-soluble and have a particle size of 50 to 400 [mu] m when applying a water-based paint to water-based ink when printing on paper a water-insoluble and organic solvent-soluble in the ink, the particle size is added fluorescent dye particles is 50 to 400 [mu] m, to print predetermined characters and patterns on the paper using a printing machine. For this reason, it is necessary to use a paper that does not use a fluorescent brightening agent. Printing may be performed while paper is being made with a paper machine (on-machine printing using a flexographic printing machine), or may be performed using a gravure printing machine after paper is made (off-machine printing). ). For example, if the characters “VOID” are printed, the characters “VOID” can be raised when attempting to falsify with an organic solvent, and these characters can be visually recognized by irradiation with ultraviolet rays.
[0027]
In the present invention, among the various methods described above, it is water-insoluble and organic solvent-soluble, and the yield of fluorescent dye particles having a particle size of 50 to 400 μm is good. Since the particle size is small, the dye particles are likely to flow out of the papermaking net), and does not contaminate the papermaking machine, etc., so that it is water-insoluble and soluble in organic solvents in the size press liquid, etc., and the particle size is 50 to 400 μm and A method of using fluorescent dye particles that are not fixed with a binder, a method of using the fluorescent dye particles together when applying a water-based paint using a coater such as an air knife coater, and an aqueous solution when printing on paper. ink is water-insoluble and organic solvent-soluble, it is preferable to employ a method of particle size adding a fluorescent dye particles is 50 to 400 [mu] m.
[0028]
Examples are described below, but parts by weight and g / m ² mean values in terms of solid content.
【Example】
Example 1
350 ml of 20 parts by weight of NBKP and 80 parts by weight of LBKP. S. F. And then added 10 parts by weight of white clay, 0.3 parts by weight of paper strength enhancer (trade name “Polystron 191”, manufactured by Arakawa Chemical Co., Ltd.), sizing agent (trade name “Size Pine E”, Arakawa) Chemical Industry Co., Ltd.) 1.0 part by weight and an appropriate amount of a sulfuric acid band were added to prepare a slurry. To this slurry, 0.08 parts by weight of water-insoluble and organic solvent-soluble fluorescent dye particles (trade name “Kayaset Yellow SF-G”, manufactured by Nippon Kayaku Co., Ltd.) having an average particle size of about 50 μm were added. Dispersed. Using this slurry, an anti-counterfeit paper having a basis weight of 100 g / m ² was made with a long paper machine according to a conventional method. At this time, a 0.2% by weight aqueous solution of polyvinyl alcohol was applied with a size press installed in the middle of the drying zone. The obtained anti-counterfeit paper did not visually recognize the presence of the fluorescent dye particles even when observed under fluorescent lamp illumination. However, fine fluorescent dye particles that developed yellow when irradiated with ultraviolet light (black light) in a dark room were observed. It was visible.
[0029]
Example 2
350 ml of 20 parts by weight of NBKP and 80 parts by weight of LBKP. S. F. And then added 10 parts by weight of white clay, 0.3 parts by weight of paper strength enhancer (trade name “Polystron 191”, manufactured by Arakawa Chemical Co., Ltd.), sizing agent (trade name “Size Pine E”, Arakawa) Chemical Industry Co., Ltd.) 1.0 part by weight and an appropriate amount of a sulfuric acid band were added to prepare a slurry. Using this slurry, a paper having a basis weight of 100 g / m ^{2 was} produced by a long paper machine according to a conventional method, and a 0.2% by weight aqueous solution of polyvinyl alcohol was formed by a size press apparatus installed in the middle of the drying zone during paper making. Apply a liquid in which 0.04% by weight of water-insoluble and organic solvent-soluble fluorescent dye particles (trade name “Kayaset Red SF-4G”, manufactured by Nippon Kayaku Co., Ltd.) with an average particle size of about 250 μm are dispersed. Then, it was dried according to a conventional method to produce a forgery prevention paper. The obtained anti-counterfeit paper did not visually recognize the presence of the fluorescent dye particles even when observed under fluorescent lamp illumination. However, fine fluorescent dye particles that develop a red color when irradiated with ultraviolet light (black light) in a dark room. It was visible.
[0030]
Example 3
350 ml of 20 parts by weight of NBKP and 80 parts by weight of LBKP. S. F. And then added 10 parts by weight of white clay, 0.3 parts by weight of paper strength enhancer (trade name “Polystron 191”, manufactured by Arakawa Chemical Co., Ltd.), sizing agent (trade name “Size Pine E”, Arakawa) Chemical Industry Co., Ltd.) 1.0 part by weight and an appropriate amount of a sulfuric acid band were added to prepare a slurry. Using this slurry, a base paper having a basis weight of 100 g / m ² was made with a long web paper machine according to a conventional method.
Next, 75 parts by weight of kaolin (trade name “UW-90”, manufactured by Engelhard Co., Ltd.), 25 parts by weight of calcium carbonate (trade name “TP-222HS”, manufactured by Okutama Kogyo Co., Ltd.), starch as a binder Water-based paint (concentration 35% by weight) mainly composed of 6 parts by weight of “MC-3000”, manufactured by Shikishima Starch Co., Ltd., and 12 parts by weight of SBR latex (trade name “Nipol LX407C” manufactured by Nippon Zeon Co., Ltd.) In accordance with a conventional method, water-insoluble and organic solvent-soluble fluorescent dye particles having an average particle size of about 150 μm (trade name “TBO”, manufactured by Sumitomo Seika Co., Ltd.) are applied to the solid content of the paint. 0.06% by weight was added. This paint was applied to both sides of the base paper by 15 g / m ² using an air knife coater, dried, and then subjected to supercalendering to produce a forgery-preventing paper. The obtained anti-counterfeit paper could not be visually recognized even when observed under fluorescent lamp illumination, but fine fluorescent dye particles that turned blue-white when irradiated with ultraviolet light (black light) in a dark room Was visible.
[0031]
Example 4
The same aqueous paint (concentration 35% by weight) as in Example 3 was prepared, and water-insoluble and organic solvent-soluble fluorescent dye particles (trade name “Kayaset Yellow SF-G”, manufactured by Nippon Kayaku Co., Ltd.) ), And (trade name “TBO”, manufactured by Sumitomo Seika Co., Ltd.) and (trade name “Kayaset Red SF-4G”, manufactured by Nippon Kayaku Co., Ltd.) are each 0.03 with respect to the solid content of the paint. Weight percent was added. This paint was applied to both sides of the base paper by 15 g / m ² using an air knife coater, dried, and then subjected to supercalendering to produce a forgery-preventing paper. The obtained anti-counterfeit paper did not visually recognize the presence of the fluorescent dye particles even when observed under fluorescent lamp illumination, but it developed a fine yellow, red, and blue-white color when irradiated with ultraviolet light (black light) in a dark room. Visible fluorescent dye particles.
[0032]
Comparative example A normal high-quality paper containing a stilbene fluorescent whitening agent (water-soluble and insoluble in an organic solvent) is given as a comparative example.
[0033]
Various representative organic solvents were dropped on the surface of the anti-counterfeit paper obtained in each example and the high quality paper of the comparative example, and the place where the organic solvent was evaporated was dropped under indoor fluorescent lighting and indoors. Table 1 shows the results of observation by irradiating with ultraviolet light (black light) under fluorescent lamp illumination. It was confirmed that the same results were obtained under natural light and under incandescent lighting.
[0034]
[Table 1]

[0035]
When a large amount of the water-insoluble and organic solvent-soluble fluorescent dye particles used in Example 1 and Example 2 are collected, they appear colored under normal lighting, but they are distributed in a trace amount in the paper as in Example. If it is used, the presence of the dye becomes invisible under normal lighting (when used in a very large amount, the hue unique to the dye becomes faint). This is because there are a small amount of fine dye particles that exceed the resolution limit of the human eye. However, when the anti-counterfeit paper obtained in these examples is irradiated with ultraviolet rays in a dark room, a fluorescent color peculiar to the dye is emitted and can be visually recognized as fine particles. The water-insoluble and organic solvent-soluble fluorescent dye particles used in Example 3 are colorless even when collected in large quantities. However, when the anti-counterfeit paper in Example 3 is irradiated with ultraviolet rays in a dark room, the dye-specific properties are unique. It emits a fluorescent color and can be visually recognized as fine particles.
[0036]
When various organic solvents are dropped onto the surface of the anti-counterfeit paper obtained in these examples, the dye contained in the paper is eluted by the action of the organic solvent and diffuses to the surroundings by capillary action. When the dropping surface was observed under fluorescent lamp illumination after the solvent had evaporated, in Examples 1 and 2, the hue due to the dye used was visible except in the case of dripping petroleum ether. In Example 3, since the dye used was colorless, the dripping surface appeared to be unchanged. In Example 4, different hues were observed in spots.
[0037]
Further, when these sheets are irradiated with ultraviolet light (black light) under fluorescent lamp illumination, in Examples 1 and 2, except for the case of dripping petroleum ether, the portion corresponding to the dripping surface fluorescently develops in a hue unique to each dye. Looked.
[0038]
As a reference, the result of dripping water instead of the organic solvent was shown, but there was no change in any case. In addition, no change was observed in the case of the high-quality paper of the comparative example.
[0039]
The above is the result of irradiating with ultraviolet light under fluorescent lighting and under fluorescent lighting, but the same result is obtained when irradiating with ultraviolet light under incandescent bulb lighting or natural light, or under incandescent bulb lighting or natural light. It was confirmed that
There are various other water-insoluble and organic solvent-soluble fluorescent dyes other than those described above, and the solubility in organic solvents is also different, so that various types of fluorescent dyes may be used depending on the performance required for anti-counterfeit paper.
[0040]
【The invention's effect】
The anti-counterfeit paper of the present invention is configured as described above and has a remarkable effect as described below.
1) Passports, traveler's checks, checks, bills, identification cards, etc. are often written with a ballpoint pen using oil-soluble ink, but the anti-counterfeit paper of the present invention is of this type of anti-counterfeit printed matter. It can be suitably used for applications, and traces of tampering with an organic solvent can be easily recognized by irradiation with ultraviolet rays even in a bright room, and the color can be colored to provide an effect that a tamper can give up on tampering.
2) In addition, scribing lottery paper (printing out of contact, concealing this printing surface with aluminum powder printing, and the purchaser rubs the aluminum powder printing part with a nail etc. to determine the winning combination. ) Can be suitably used. In other words, in the distribution process before the lottery is sold, it is a crime to remove the aluminum powder printing part using an organic solvent, read the winnings, steal only the winning lottery, and print the aluminum powder again in the lottery The prevention effect is great.
3) Since there are many types of water-insoluble and organic solvent-soluble fluorescent dyes, for example, the type and amount of the fluorescent dye may be changed for each lot and added to the paper. The anti-counterfeit paper of the present invention can also be suitably used for applications where it can be determined whether the product is a lot product.

Claims

Water insoluble and organic solvent-soluble, is contained in the paper by particle size 50~400μm der Ru fluorescent dye particles of a particle state, as traces of tampering by an organic solvent can be visually recognized upon irradiation with ultraviolet rays Anti-counterfeit paper characterized by

The fluorescent dye particles, falsification paper according to claim 1, wherein the under normal light source is a matter that can not be visually recognized, which is included in the paper.

The fluorescent dye particles, anti-falsification paper according to claim 1 or 2, characterized in that coloring in different color upon irradiation with ultraviolet rays contained in the paper.

Any one of claims 1 to 3, characterized in that it contains the pre Kihotaru light dye particles the forgery preventing paper are formed by at least three or more layers paper making adjustment, and only in the inner layer Anti-counterfeit paper as described in 1.

Anti-falsification paper according to any one of claims 1 to 3 before Kihotaru light dye particles, characterized in that is present in the vicinity of the paper surface.

Anti-falsification paper according to claim 5, before Kihotaru light dye particles characterized in that it is included in the character or pattern printed on the paper.