JP2004280863A - Method and device for manufacturing recording medium - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To manufacture a recording medium provided with a protecting layer which is flat and homogeneous over the whole surface. <P>SOLUTION: The liquid drops of an ultraviolet curing resin solution are jetted onto a rotating substrate 1 by using liquid drop jet head 103 which can control and jet minute liquid drops. A large number of liquid drops of the ultraviolet curing resin solution are attached uniformly on the substrate by moving the liquid drop jet head 103 from the inner circumference of the substrate to the outer circumference to form a coating film. The obtained coating film is extremely flat over the whole surface, and such an annular protruding part of the outer circumference that is formed by the spin coating method is not formed. The protecting layer is formed by curing the coating film by irradiating the film with ultraviolet rays. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

【００５５】
次いで、反射層５上に、図２及び図３に示した製造装置１００を用いて、上記動作に従って保護層６を形成する。保護層６の膜厚は、２〜２０μｍの範囲から選択可能であり、特に５〜１５μｍの範囲から選択することが望ましい。前述した製造装置の動作に従って保護層６を形成することにより、保護層６表面の凹凸は内周から外周まで平均で５〜１０μｍ以下であり、平坦な保護層を得ることができる。また、保護層の外周部分には環状の突出部が形成されないため、図１（ｃ）に示すように、光磁気ディスク１０の外周部においても磁気ヘッド６１を一定の高さで浮上させることができる。光磁気記録層３の直径４０ｍｍ〜１１８ｍｍまでの領域を記録領域として用いることができ、有効記録領域を広く確保することができる。
【００５６】
〔情報の記録及び再生〕
以上のように作製した光磁気ディスク１０は、前述のように保護層の膜厚がディスク面内で均一であるために、磁気ヘッドを記録層に近接させる必要のある磁界変調記録方式に好適である。以下に、その実施例を示す。レーザー波長７８０ｎｍ、レンズ開口数（ＮＡ）０．５５の光ピックアップを用い、線速７．５ｍ／ｓで記録再生を行った。記録に際しては、レーザービームをパルス状に照射しつつ、記録する情報に応じて変調した外部磁界を印加した。レーザーパワーは、ピーク値で１２ｍＷ、デューティ比５０％とした。また、外部磁界は±２００Ｏｅで変調した。長さ０．７μｍの連続繰返しパターンを記録し、レーザーパワー１．５ｍＷで再生し、ＣＮ比で４５ｄＢ以上を得た。なお、本ディスクに対しては、光変調記録方式を用いることも可能である。
【００５７】
【実施例２】
本実施例では、図１に示した光磁気ディスク１０の保護層６を、実施例１における製造装置１００の液滴噴射ヘッド１０３及び紫外線照射装置１１２を並行して駆動することによって形成する方法について、図１０及び図１１を用いて説明する。
【００５８】
まず、基板１をターンテーブル１０１により回転させ、液滴噴射ヘッド１０３を、基板１内周側の噴射開始位置の直上に位置付ける。そして、図１０に示すように、液滴噴射ヘッド１０３により液滴を基板１上に噴射させながら、液滴噴射ヘッド１０３を基板内周側から外周側へ所定のピッチで移動させる（矢印ＡＲ１０ａ）。次いで、液滴噴射ヘッド１０３による液滴噴射を開始し所定時間が経過した後、紫外線照射装置１１２を駆動して、紫外線ランプ１１３を基板１内周側に位置付ける。そして、図１０及び１１に示すように、紫外線ランプ１１３を基板１内周側から外周側に移動させて（矢印ＡＲ１０ｂ）、液滴噴射ヘッド１０３により基板１上に形成された樹脂液の塗膜６’を硬化させる（保護層６）。このように、液滴噴射ヘッド１０３による液滴の噴射と紫外線照射装置１１２による紫外線照射を並行して行なう方法は、基板上に保護層を短時間で形成することができるので、生産性に優れる。
【００５９】
【実施例３】
本実施例では、図１に示した光磁気ディスク１０の保護層６を、図１２及び図１３に示すような製造装置２００を用いて形成する方法について示す。図１３には、図１２（ｂ）のＸ−Ｘ’線断面を示した図である。なお、図１３では、便宜上、ボールねじ２０５の右側部分及びモータ２０６は省略している。図１２に示した製造装置２００は、基板の直径よりも長さの長いボールねじ２０５を有しており、液滴噴射ヘッド２０３を搭載したスライドテーブル２０４が、基板の直径方向において基板の一方の外周端から他方の外周端まで移動可能であり、液滴噴射ヘッド２０３の移動方向と紫外線照射装置２１２の移動方向が直交している以外は、実施例１の製造装置１００と同じ構造を有している。かかる製造装置２００の動作について、以下に説明する。
【００６０】
まず、基板１をターンテーブルにより回転させる。次いで、図１２（ａ）に示すように、液滴噴射ヘッド２０３を搭載したスライドテーブル２０４及び紫外線ランプ２１３を基板１の外周端の直上に位置付ける。そして、液滴噴射ヘッド２０３により基板１の外周側から液滴の噴射を開始するとともに、液滴噴射ヘッド２０３を基板の中心に向かって所定のピッチで移動させる（矢印ＡＲ１２ａ）。液滴の噴射から所定の時間が経過した後、紫外線照射装置２１２を駆動して、紫外線ランプ２１３により紫外線の照射を行ないながら紫外線ランプ２１３を基板の外周側から中心に向かって移動させる（矢印ＡＲ１２ｂ）。こうして、基板１の外周側から液滴の噴射及び紫外線照射による樹脂液の塗膜の硬化を並行して行なう。
【００６１】
液滴噴射ヘッド２０３が基板１の内周側の端部に位置付けられ、基板１上に樹脂液の塗膜が形成されると、液滴噴射ヘッド２０３からの液滴の噴射を一端停止させる。更に、紫外線ランプ２１３が基板１の内周側端部に位置付けられ、基板上に形成された樹脂液の塗膜が硬化されて、保護層が形成される。ここで、紫外線ランプ２１３による紫外線照射も一端停止させる。
【００６２】
次いで、図１２（ｂ）及び図１３（ａ）に示すように、液滴噴射ヘッド２０３が基板１の中心部を越えて更に移動し、基板の内周側端部に位置付けられたとき、液滴噴射ヘッド２０３により液滴の噴射を再度開始するとともに、液滴噴射ヘッド２０３を基板１内周側から外周側に移動して（矢印ＡＲ１２ｃ）、上記方法により形成された保護層６上に液滴を更に付着させて樹脂液の塗膜６’を形成する。そして、紫外線照射装置２１２を駆動して紫外線ランプ２１３により基板内周側に形成された樹脂液の塗膜６’に紫外線を照射しながら、図１３（ａ）及び（ｂ）に示すように、紫外線ランプ２１３を内周側から外周側に移動させる（矢印ＡＲ１２ｄ）。こうして、保護層６上にもう１層の保護層６を積層することができる。このような形成方法により、例えば、１層目の保護層を１０μｍの厚みで形成し、その上に２層目として２０μｍの保護層を積層させて、約３０μｍの膜厚の保護層を形成することもできる。
【００６３】
また、上記操作を繰り返し行なうことによって、保護層を何層も重ねて形成することができる。これにより、保護層の膜厚を厚くすることができ、例えば、１００μｍ以上の所望の膜厚の保護層を形成することも可能である。また、かかる方法により得られた保護層は、その表面が平坦であり、膜厚も均一である。
【００６４】
【実施例４】
本実施例では、図１に示した光磁気ディスク１０の保護層６を、図１４及び図１５に示すような製造装置３００を用いて形成する方法について示す。製造装置３００は、図１４及び図１５に示すように、ボールねじ３０５、液滴噴射ヘッド３０３、モータ３０６、支持部３０７、基板載置台３０１から主に構成されている。液滴噴射ヘッド３０３は、図１５に示すように、スライドテーブル３０４の下端に設けられている。スライドテーブル３０４は、基板載置台３０１の直径方向に延在するボールねじ３０５上を摺動可能に係合されている。ボールねじ３０５の長さは、基板載置台３０１の直径よりも長く、ボールねじ３０５の一方の端部が、ボールねじ３０５を回転可能に支持する支持部３０７により支持され、ボールねじ３０５の他方の端部はモータ３０６と回転可能に接続されている。モータ３０６を駆動してボールねじ３０５を回転させることにより、スライドテーブル３０４をボールねじ３０５上でスライド移動させることができる。スライドテーブル３０４により移動される液滴噴射ヘッド３０３の基板直径方向における位置は、制御装置３０９でモータ３０６の駆動を制御することにより制御される。液滴噴射ヘッド３０３は複数のノズルを有し、それぞれのノズルは、スライドテーブル３０４の移動方向（図１４中、左右方向）に垂直な方向（図１４中、上下方向）に並んで配置されている。また、液滴噴射用ヘッド３０３には、不図示の液体タンクから紫外線硬化樹脂を含む溶液が供給される。基板載置台３０１は、不図示の搬送装置により、スライドテーブル３０４の移動方向と垂直な方向（図１４中、上下方向）に所定のピッチで移動することができる（矢印ＡＲ１４）。また、基板載置台３０１には、図１５に示すように、円柱形突起３１０が形成されており、円柱形突起３１０は、基板載置台３０１上に基板１が載置されたときに、基板１の中心部のスピンドル孔１ａに挿入され、基板１の動き（ずれ）や振動を抑えるスピンドルの機能を果たしている。
【００６５】
以下、かかる製造装置３００の動作について説明する。基板載置台３０１の移動により、基板１を、基板１の基板載置台３０１の移動方向（図１４中、上下方向）の外周端部１ｂが液滴噴射ヘッド３０３の移動軸の直下になるように位置付ける。次いで、モータ３０６を駆動して、液滴噴射ヘッド３０３が基板１を横切るように、例えば、支持部３０７側からモータ３０６側に液滴噴射ヘッド３０３をスライド移動させる。このとき、液滴噴射ヘッド３０３からの液滴が基板１の所定領域に付着するように液滴噴射ヘッド３０３の液滴噴射を制御する。そして、液滴噴射ヘッド３０３がモータ３０６側に移動したとき、不図示の搬送装置を駆動して基板載置台３０１を所定のピッチで図面上方向（矢印ＡＲ１４の方向）に移動させる。次いで、液滴噴射ヘッド３０３をモータ３０６側から支持部３０７側に移動させながら、液滴噴射ヘッド３０３が基板１上を走査したときにのみ液滴噴射ヘッド３０３から液滴を噴射させて、基板１上の所定領域に液滴を付着させて樹脂液の塗膜６’を形成する。液滴噴射ヘッド３０３が、支持部３０７側に移動したとき、基板載置台３０１の移動により基板１を所定のピッチで図面上方に移動させる（矢印ＡＲ１４）。かかる動作を繰り返し行なって基板１上に樹脂液の塗膜６’を形成することにより、基板１上に保護層を形成することができる。
【００６６】
上記動作において、液滴噴射ヘッド３０３が、基板１上の保護層を形成しない領域、例えば、スピンドル孔１ａを含む非塗布領域１ｃ上を横切るときは、基板１の非塗布領域１ｃに液滴が噴射されないように制御する。
【００６７】
本実施例において、基板１の厚み、形状及び材質等について制限はなく、任意の基板を用い得る。また、基板上において、液滴を噴射する領域を予め多数の独立した領域に分割しておき、それら独立した領域を順番に液滴噴射ヘッドで走査して液滴を噴射することも可能である。
【００６８】
【実施例５】
本実施例では、本発明に従う製造装置として、図１６に示した製造装置４００を用いて追記型コンパクトディスク（ＣＤ−Ｒ）を製造した。図１６に示すように、製造装置４００は、主に、ロータリアクチュエータ４０７、スイングアーム４０５、液滴噴射ヘッド４０３及び制御装置４０９を備える。液滴噴射ヘッド４０３は、スイングアーム４０５の先端に取り付けられている。スイングアーム４０５は、ロータリアクチュエータ４０７の中心軸を中心として扇状に移動し、これにより液滴噴射ヘッド４０３を基板上の所定位置に位置付けることができる。基板１１は、不図示の回転モータより回転可能なターンテーブル（不図示）に載置され、図１６中の矢印ＡＲ１６の方向に回転可能である。制御装置４０９は、液滴噴射ヘッド４０３と基板１１表面との距離、液滴噴射ヘッド４０３からの液滴の噴射量、液滴の噴射時間、液滴噴射ヘッド４０３の移動量等を制御することができる。また、制御装置４０９は、液滴噴射ヘッド４０３が基板１１上に位置付けられたとき、液滴噴射ヘッド４０３の直下の位置における基板１１の線速度または角速度が常に一定になるように、基板１１の回転数を制御することができる。また、液滴噴射は、実施例１と同様に制御した。
【００６９】
かかる製造装置４００を用いて、追記型のコンパクトディスクを製造することができる。追記型のコンパクトディスクは、図１７に示すように、基板１１上に、記録層１３、光反射層１５及び第１保護層１６を備え、また、基板１１の記録層１３等の形成面とは反対の面に第２保護層１７を備えた構造を有する。なお、記録層１３は、フタロシアニン色素を主成分とする有機色素膜である。
【００７０】
基板１１として、板厚１．２ｍｍ、直径１２０ｍｍの透明で光学特性の良好なポリカーボネート樹脂基板を用いた。基板１１の片側の面には、凹凸のプリフォーマットパターンを有する。かかる基板１１を、プリフォーマットパターンが形成された面が上になるように、図１６の製造装置４００に装着する。まず、ロータリアクチュエータ４０７を駆動して液滴噴射ヘッド４０３を基板１１の外周側に位置付ける。基板１１を回転させ、液滴噴射ヘッド４０３からフタロシアニン有機色素を主成分とする液滴を、基板１１のプリフォーマットパターンが形成された面上に噴射しながら、ロータリアクチュエータ４０７の回転により液滴噴射ヘッド４０３を基板１１の内周側に向かって所定のピッチで移動させる。このとき、液滴噴射ヘッド４０３の直下の位置における基板１１の線速度が一定になるように、制御装置４０９により不図示の回転モータの回転数を制御した。こうして、基板１１上にフタロシアニン有機色素を主成分とする薄膜を形成した。そして、得られた薄膜を乾燥させることにより、フタロシアニン有機色素を主成分とする記録層１３を形成した。
【００７１】
ここでは、液滴の材料として、フタロシアニン有機色素が主成分の材料からなる溶液を用いたが、フタロシアニン有機色素と有機溶媒と添加剤とからなる溶液、あるいは、シアニン有機色素、アゾ色素等の任意の色素材料を用いてもよい。
【００７２】
次に、記録層１３上に、プラズマ蒸着法またはスパッタ法により、Ａｕからなる光反射層１５を形成した。次いで、Ａｕからなる光反射層１５上、及び、基板１１のプリフォーマットパターンが形成されている面と反対側の面上に、紫外線硬化樹脂からなる第１保護層１６及び第２保護層１７を形成する。第１及び第２保護層１６，１７の形成には、図１６に示した製造装置４００を用いることができる。この場合は、液滴の材料として紫外線硬化樹脂を用いる。記録層１３の形成と同様にして、紫外線硬化樹脂からなる層を形成できる。紫外線硬化樹脂層が形成された基板は、図３に示すような、紫外線照射装置１１２を備える製造装置に装着される。かかる製造装置を用いて、紫外線硬化樹脂層に紫外線を照射して紫外線硬化樹脂層を硬化させる。こうして、Ａｕからなる光反射層１５上、及び、基板１１のプリフォーマットパターンが形成されている面と反対側の面上に、それぞれ紫外線硬化樹脂からなる第１保護層１６及び第２保護層１７を形成した。これらの保護層は、例えば、約１０μｍの膜厚で形成する。これにより、追記型コンパクトディスク（ＣＤ−Ｒ）を作製した。
【００７３】
特に、本発明の製造方法は、基板の一部分にのみ所望の塗膜を形成したい場合に好適である。図２２にその例を示す。再生専用情報（ＲＯＭ）領域５１と追記可能（Ｒ）領域５２が混在する媒体５０、いわゆるパーシャルＲＯＭディスクにおいて、追記可能領域５２が比較的小さな領域で十分な場合、その必要部分にのみ有機色素を塗布して追記可能領域５２を確保すればよい。その際に、従来のスピン塗布方式を用いると、塗布領域を正確に制御することができず、再生専用情報領域と追記可能領域とを正確に分離することができない。本発明を適用することにより、必要な領域にのみ有機色素を高精度に塗布することが可能である。特に、内周部のみに塗布したり、あるいは任意の形、範囲に塗布することが可能である。
【００７４】
【実施例６】
本実施例では、実施例１における製造装置１００を用いて、１２０ｍｍ径のコンパクトディスクを製造する。コンパクトディスクは、図１８に示すように、透明基板２１上に、反射層２５及び保護層２６を有する。透明基板２１にはポリカーボネート樹脂基板を用い、樹脂基板２１の片面にはプリフォーマットパターンが形成されている。透明基板２１は、直径１２０ｍｍ、板厚１．２ｍｍである。保護層２６は、透明基板２１と保護層２６との間に形成される反射層２５を、腐食等の化学的な変化から防ぐための層であり、反射層２５に化学反応を誘発する物質が透過しない光透過性の材料、例えば、紫外線硬化樹脂等の材料を用いる。反射層２５にはＡｌを用い、マグネトロンスパッタ装置により形成する。
【００７５】
保護層２６は、紫外線硬化樹脂を材料として用いて、実施例１における製造装置１００により形成することができる。即ち、図２に示す液滴噴射ヘッド１０３を用いて反射層２５上に紫外線硬化樹脂の液滴を付着させ、反射層２５上に紫外線硬化樹脂の塗膜を形成する。次いで、図３に示す紫外線照射装置１１２を用いて紫外線硬化樹脂の塗膜に紫外線を照射して硬化させることにより保護層２６を形成する。こうして、図１８に示す積層構造を有するコンパクトディスクを製造することができる。
【００７６】
以上、本発明の製造方法及び製造装置について、実施例により具体的に説明したが、本発明はこれらに限定されるものではない。例えば、上記実施例では、記録媒体として光磁気ディスク、追記型コンパクトディスク（ＣＤ−Ｒ）及びコンパクトディスクを作製したが、相変化型光記録媒体、ミニディスク（ＭＤ）、貼り合わせ型の光記録媒体等の任意の記録媒体を製造することができる。また、上記実施例では、液滴噴射ヘッドを用いて、紫外線硬化性樹脂からなる保護層、有機色素からなる記録層を形成したが、例えば、磁気ディスクの潤滑剤層や、貼り合わせ型光記録媒体において媒体同士の貼り合わせに用いる接着剤も形成することができる。これら各目的に応じて塗布される各液体を、実施例１〜５で述べた各種構造の製造装置を用いたいずれの方法によっても塗布することが可能であり、実施例の組合せに限定されるものではない。また、必要に応じて紫外線照射を選択的に行うこともできる。
【００７７】
さらに、本発明は、基板上にプリフォーマットパターンを形成するためのレプリケーション工程に適用することができる。この工程に本発明を適用するには、▲１▼まず、液滴噴射ヘッドを有する本発明の製造装置に紫外線硬化樹脂を充填する。次いで、▲２▼当該製造装置により、スタンパ上の所望の領域に紫外線硬化樹脂を均一に塗布し、▲３▼塗布した紫外線硬化樹脂上にガラス等の基板を押圧して貼りつける。次いで、▲４▼紫外線照射により紫外線硬化樹脂を硬化させ、▲５▼スタンパから基板とともに硬化した紫外線硬化樹脂を剥離する。以上のプロセスを経ることにより、樹脂の高速塗布が可能であるとともに、必要な領域に必要な量のみの樹脂を塗布することができるので、樹脂がはみ出すことがなく、ふき取り工程が不要となる。これらの方法は、２層型ＤＶＤ等の多層記録型の光ディスクにおけるプリフォーマット面形成時においても用いることができるので、多層記録型の光ディスクの生産性を向上させることが可能となる。
【００７８】
【発明の効果】
本発明の製造方法は、紫外線硬化樹脂液や有機色素溶液、潤滑剤、接着剤等の液状の材料を、微小な液滴にして基板上に均一に付着させることができるので、それら液状の材料からなる薄膜を基板上に均一に且つ平坦に形成することができる。それゆえ、紫外線硬化性樹脂からなる保護層や有機色素からなる記録層、潤滑剤からなる潤滑層、接着剤からなる接着層を備える記録媒体を製造するための製造方法として最適である。また、本発明の製造方法では、スピン塗布法を用いた場合のように、保護層外周部に環状の突出部は形成されないので、得られた記録媒体は従来の媒体に比べて記録可能な領域が広くなり、記録容量を増大させることができる。
【００７９】
また、本発明の製造方法では、基板を必ずしも回転させる必要はないので、スピン塗布法では薄膜の形成ができなかったような形状の基板にも薄膜を形成することができる。また、本発明では、液滴の噴射により形成された塗膜上に更に続けて塗膜を形成することもできるので、塗膜内においてピンホールの発生を防止できる。また、液滴の噴射による塗膜の形成と紫外線照射による塗膜の硬化を並行させることができるので、記録媒体の生産効率を向上させることができる。
【００８０】
本発明の製造装置は、液滴噴射ヘッドにより液状の材料を基板上に均質に且つ平坦に形成することができるので、本発明の製造方法を実現することができる。また、本発明の製造装置は、液滴噴射ヘッドにより基板上の所望の領域にのみ液滴を噴射して薄膜を形成するので、余分な材料が発生せず極めて経済的である。
【００８１】
また、本発明の製造装置は、液滴噴射ヘッドにより基板上の微小な領域に液滴を噴射することができるので、基板上の所望の領域に部分的に薄膜を形成することもできる。また、本発明の製造装置は、液滴噴射ヘッドを基板上の任意の領域に位置付けて液滴噴射させることができるので、基板上のいずれの場所にも薄膜を形成することが可能である。有機色素を含有する溶液を用いて記録層を形成する場合、例えばパーシャルＲＯＭディスクの追記可能領域のような所定領域のみに、有機色素を含有する溶液を塗布することができる。
【００８２】
さらに、本発明の製造方法では、樹脂の高速塗布が可能であり、また、必要な領域に必要な量のみの樹脂を塗布することができるので、ガラス２Ｐ法における樹脂の塗布に関わる問題を解消して、記録媒体の生産効率を向上させることができる。
【図面の簡単な説明】
【図１】図１（ａ）は、それぞれ、実施例１で製造する光磁気ディスクの概略断面図であり、図１（ｂ）は、光磁気ディスクの積層構造図であり、図１（ｃ）は、図１（ａ）で示した領域Ｓ３の部分拡大断面図である。
【図２】実施例１で用いた本発明に従う製造装置の概略構成図であり、液滴噴射ヘッドを駆動した様子を示している。
【図３】実施例１で用いた本発明に従う製造装置の概略構成図であり、紫外線照射装置を駆動した様子を示している。
【図４】液滴噴射ヘッドの液滴噴射部のノズルの配置を示す図であり、図４（ａ）はノズルが基板半径方向に並んで配列している様子を示し、図４（ｂ）はノズルが基板半径方向に対して斜めに並んで配列している様子を示す。
【図５】液滴噴射部から液滴が噴射する原理を説明するための図である。
【図６】図６（ａ）は、実施例１の製造装置で用いた液滴噴射ヘッドの構造を模式的に示した斜視図であり、図６（ｂ）は、図６（ａ）を正面方向（Ａ方向）から見た図であり、図６（ｃ）は、図６（ａ）を側面方向（Ｂ方向）から見た図である。
【図７】本発明に従う製造装置を用いて基板上に保護層を形成する工程を説明するための図であり、図７（ａ）は液滴噴射を開始する工程を示し、図７（ｂ）は液滴噴射を実行している工程を示し、図７（ｃ）は、液滴噴射が終了した工程を示し、図７（ｄ）は紫外線を照射する工程を示す。
【図８】液滴噴射ヘッドを駆動して基板上に液滴を噴射している様子を示す図である。
【図９】液滴噴射ヘッドにより基板上に付着された液滴の様子を説明する、図８に示した領域Ｓ２の部分拡大図である。
【図１０】液滴噴射ヘッドと紫外線照射装置を並行して駆動させる方法を説明するための図であり、紫外線ランプが基板内周側に位置付けられたときの概念図である。
【図１１】液滴噴射ヘッドと紫外線照射装置を並行して駆動させる方法を説明するための図であり、紫外線ランプが基板外周側に位置付けられたときの概念図である。
【図１２】実施例３で用いた本発明に従う製造装置の概略平面図であり、図１２（ａ）は、液滴噴射ヘッド及び紫外線ランプが基板外周部の直上に位置付けられている様子を示し、図１２（ｂ）は、形成された保護層上に更に保護層を形成している様子を示す。
【図１３】図１３（ａ）は、図１２（ｂ）に示した製造装置のＸ−Ｘ’線断面図であり、図１３（ｂ）は、保護層の重ね塗りが終了したときの製造装置の概略断面図である。
【図１４】実施例４で用いた、本発明に従う製造装置の概略平面図である。
【図１５】図１４に示した製造装置の概略断面図である。
【図１６】実施例５で用いた、本発明に従う製造装置の概略平面図である。
【図１７】実施例５で製造した追記型コンパクトディスクの積層構造を示す図である。
【図１８】実施例５で製造したコンパクトディスクの積層構造を示す図である。
【図１９】スピン塗布法を説明するための図であり、図１９（ａ）は基板上に塗布液を載せた状態、図１９（ｂ）は基板を回転させた状態、図１９（ｃ）は基板の回転を終了した状態、図１９（ｄ）は紫外線を照射した状態を示す。
【図２０】図２０（ａ）は、従来の光磁気記録媒体の概略断面図であり、図２０（ｂ）は、媒体上を移動する磁気ヘッドと保護層の外周部の盛り上がった部分との関係を概念的に示す、図２０（ａ）に示した領域Ｓ３の部分拡大断面図である。
【図２１】図２１（ａ）及び（ｂ）は、ぞれぞれ、従来の光磁気記録媒体の概略平面図及び概略断面図であり、図２１（ｃ）は、図２１（ｂ）に示した領域Ｓ４の部分拡大断面図である。
【図２２】パーシャルＲＯＭディスクの概略図である。
【図２３】２層型ＤＶＤの断面模式図である。
【符号の説明】
１，３１ 基板
２，３２ 第１誘電体層
３，３３ 光磁気記録層
４，３４ 第２誘電体層
５，３５ 反射層
６，３６ 保護層
１０ 光磁気ディスク
６０ 光ヘッド
６１ 磁気ヘッド
７４ 半透明層
７５ 反射層
７６ 保護層
７７ 第１のプリフォーマット面
７８ 第２のプリフォーマット面
１００，２００，３００，４００ 製造装置
１０３ 液滴噴射ヘッド
１０４ スライドテーブル
１０９ 制御装置
１１２，２１２ 紫外線照射装置
１１３，２１３ 紫外線ランプ
１１４，２１４ アーム
１１５，２１５ 支持部
１ａ，１１ａ，３１ａ スピンドル孔[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a method and an apparatus for manufacturing a recording medium, and more particularly, to a method and an apparatus for manufacturing a recording medium having a layer formed by applying a liquid material.
[0002]
[Prior art]
In recent years, recording media such as magneto-optical recording media and phase-change optical recording media have been reduced in size, thickness, and weight. For example, video disks such as phase-change optical disks or magneto-optical disks have been developed with small diameters from 5.25 inch diameter to 3.5 inch diameter, 2.5 inch diameter and 1.8 inch diameter. ing.
[0003]
An optical disc is usually provided with a protective layer for protecting a layer such as a recording layer formed on a substrate. The protective layer is made of a resin material such as an ultraviolet curable resin, and is usually formed by a spin coating method. Such a spin coating method will be briefly described below with reference to the drawings.
[0004]
FIGS. 19A to 19D are diagrams conceptually showing the steps of the spin coating method. As shown in FIG. 19A, the disk substrate 31 on which the recording layer 33 and the like are formed is placed and fixed on a turntable 501 of the spin coater 500, and a resin material 36 is provided on the inner peripheral portion of the disk substrate 31. 'Is applied in a donut shape. Next, a motor (not shown) is driven to rotate the turntable 501 at a speed of, for example, 4000 rpm, and as shown in FIG. 19B, the resin material 36 formed on the inner peripheral portion of the disk substrate 31 is rotated. 'Is spread outward by centrifugal force. Thus, a resin film is formed on the entire surface of the disk as shown in FIG. When an ultraviolet curable resin is used as the resin material 36 ', as shown in FIG. 19D, the resin film 36' is irradiated with ultraviolet rays 513 to be polymerized and cured (resin film 36). At this time, as shown in FIG. 19D, the resin 36a present on the outer peripheral portion of the disk substrate 1 is formed to be higher than the resin 36 in other regions. That is, the protection layer formed by the spin coating method has an annular protrusion formed on the outer periphery. The projecting portion on the outer peripheral portion of the protective layer has caused the following inconvenience.
[0005]
[Problems to be solved by the invention]
In the case of a magneto-optical disk, as shown in FIGS. 20A and 20B, an optical head 60 is arranged on the substrate 31 side, and a magnetic head 61 is arranged on the protective layer 36 side to record and reproduce information. As shown in FIG. 20B, in order to reliably apply the magnetic field from the magnetic head 61 to the recording layer 33, the distance Mr between the tip of the magnetic head 61 and the recording layer 33 is set to about 7 to 30 μm. There is a need to. However, as described above, the protective layer 36 formed by using the spin coating method has the protruding portion 36a formed on the outer peripheral portion and the thickness Mo is larger than Mr and is 30 μm or more. When the magnetic head 61, which was flying at a constant height of 5 to 10 μm above, was positioned at the outer peripheral portion, the magnetic head 61 collided with the protruding portion 36a of the protective layer, and there was a problem that recording and reproduction could not be performed. In order to solve this problem, for example, when the magnetic head 61 is positioned at the outer peripheral portion of the disk, the magnetic head 61 does not collide with the annular protruding portion 36a of the protective layer 36, so that the outer peripheral projecting portion 36a Even if the magnetic head 61 is controlled so as to be lifted while sliding on the surface, the distance between the magnetic head 61 and the recording layer 33 exceeds Mr. It is difficult to record information in the system.
[0006]
In the magneto-optical disk, as shown in FIGS. 21A and 21B, the recording layer 33 is formed in a region from the diameter Db to the diameter De with respect to the diameter Da of the optical disk. Although the area 30b of the recording layer 33 having a diameter Dc to Dd is used for actual recording, the area 30c having a diameter Db to Dc and the area 30a having a diameter Dd to De cannot be used for actual recording. It is designed as standard. The region 30c located on the outer periphery of the recording layer 33 is designed so as not to be used for recording. As described above, since the protrusion on the outer periphery of the protective layer exists, recording and reproduction cannot be performed. Because. FIG. 21C schematically shows the cross-sectional structure of the portion indicated by S4 in FIG. 21B. As shown in FIG. 21C, the film thickness of the protective layer 36 is H on average in the recording area 30b. ₁ On the other hand, in the region 30c in the outer peripheral portion, the average value H ₁ Thicker, up to H ₂ It has become. Such a protrusion 36a has a substantially constant width L regardless of the diameter of the optical disc. ₁ Is formed. Therefore, the smaller the diameter of the magneto-optical disk, the larger the proportion of the unrecordable area to the recording area of the recording layer. In order to increase the recording capacity of a small-diameter magneto-optical disk, it is necessary to increase the recording density and increase the recordable area, so the protrusions on the outer periphery of the protective layer hinder the increase in the recording capacity. Had become.
[0007]
By the way, in a write-once optical recording medium, an organic dye is used for a recording layer, and such a recording layer is also formed by a spin coating method. In the spin coating method, a coating liquid such as an organic dye solvent is dropped on the inner peripheral portion of a rotating substrate, and the coating liquid is spread to the outer peripheral side using centrifugal force to form a coating film. Since the liquid was shaken off, a larger amount of coating liquid was required than the amount of the coating film actually formed on the substrate. Since organic dyes are very expensive, there is a problem that forming a film of an organic dye by a spin coating method causes waste and increases the manufacturing cost.
[0008]
In addition, conventionally, an ultraviolet curable resin is applied on a glass disk having a flat surface, and a metal stamper on which a pattern reverse to the concave and convex pattern of pits and guide grooves to be transferred is pressed, and then ultraviolet light is applied. Irradiation is performed to cure the ultraviolet curable resin, and finally the stamper is peeled off, that is, a so-called glass photopolymer method (glass 2P method) has been used. However, in this method, it takes a long time to apply the ultraviolet curable resin and wipe off the protruding resin, so that low productivity has been a problem.
[0009]
Recently, a medium such as a DVD having two preformatted surfaces has been used (see FIG. 23). In this medium 70, two preformat surfaces 77 and 78 are formed at a distance of about several tens of μm from each other, and the focal position F of light from an optical head is ₁ And F ₂ , The two preformat surfaces 77 and 78 can be accessed. When the medium 70 is manufactured, the first preformat surface 77 is formed by injecting a resin material such as polycarbonate into a mold in which a stamper is set. On the other hand, the second preformat surface 78 is mainly formed by using the above-described photopolymer method, and has a productivity problem similarly to the method of manufacturing a G / 2P (glass 2P) substrate. .
[0010]
SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems of the prior art, and a first object of the present invention is to provide a method and a method for manufacturing a recording medium capable of forming a thin film made of a liquid material uniformly and flatly on a substrate. It is to provide a device.
[0011]
A second object of the present invention is to provide a method and an apparatus for manufacturing a recording medium provided with a protective layer having no bulge on the outer peripheral portion, particularly, a disk-shaped recording medium having a small diameter.
[0012]
A third object of the present invention is to provide a method and an apparatus for manufacturing a recording medium capable of forming an expensive liquid material such as an organic dye solvent on a substrate at low cost without generating an extra material. It is in.
[0013]
[Means for Solving the Problems]
According to a first aspect of the present invention, there is provided a method of manufacturing a recording medium including a thin film on a substrate,
Forming a thin film by ejecting a droplet containing a material constituting the thin film onto the substrate while relatively moving a position of ejecting the droplet with respect to the substrate. A method for manufacturing a recording medium is provided.
[0014]
In the manufacturing method of the present invention, the droplet is attached to a predetermined region on the substrate by spraying the droplet onto the substrate. Then, a thin film is formed on the substrate by continuously ejecting the droplet while moving the substrate relatively to the ejection position of the droplet. At that time, it is possible to move a mechanism (droplet ejection head) for ejecting droplets, move the substrate, or move both at the same time. The thin film thus obtained has a small difference in unevenness, is flat and uniform, and has, for example, a height of a protruding portion projecting on the surface of 5 to 10 μm or less, preferably 5 μm or less. In the present invention, the term “substrate” is a concept including a substrate on which layers necessary for the configuration of a recording medium, such as a recording layer and a reflective layer, are formed.
[0015]
According to the manufacturing method of the present invention, a plurality of droplets can be made to adhere to the substrate by one injection. At this time, droplets can be attached to the substrate at arbitrary intervals, but it is desirable to eject the droplets so that the droplets overlap each other so that there is no gap between the attached droplets. As a result, droplets can be uniformly attached to the substrate. Such a manufacturing method is different from a manufacturing method using a so-called spray method. That is, in the spraying method, the liquid is sprayed onto a relatively large area on the substrate at once, so that the liquid droplets adhere to the substrate unevenly. In the present invention, a small area (for example, several hundred microns square) of the substrate is used. Since the droplets are ejected in substantially equal amounts (for each region), the droplets are regularly arranged and adhered onto the substrate. In addition, in the manufacturing method using the spray method, the liquid may be sprayed to an area other than the substrate, which may cause waste. However, according to the manufacturing method of the present invention, the droplet is attached only to a desired area on the substrate. It is efficient because it can be.
[0016]
In the present invention, when the substrate has a disk shape, droplets can be ejected onto the substrate while rotating the substrate around the central axis. At this time, the droplet can be attached to the entire surface of the substrate by moving the position for ejecting the droplet from the inner circumference to the outer circumference or from the outer circumference to the inner circumference in the disk radial direction.
[0017]
The production method of the present invention is applied to a recording medium having a layer conventionally formed by a spin coating method, for example, a protective layer made of a resin material on an uppermost layer, or a substrate having a flat surface (for example, a glass substrate). It is extremely suitable as a method for forming an optical disk having a layer for forming a preformat pattern such as prepits, a write-once optical disk having a recording layer made of an organic dye, a magnetic disk having a lubricating layer on the uppermost layer, and the like. It is also optimal as a method for forming each preformat layer in a multilayer recording type optical disc which is accessed by changing the focal position of the optical head in the thickness direction of the disc.
[0018]
In the manufacturing method of the present invention, when the thin film to be formed is, for example, a protective layer formed from a photocurable resin, a solution containing the photocurable resin as a material for the droplets was used, and was sprayed onto the substrate. The droplet can be cured by irradiating the droplet with an energy ray. At this time, it is preferable to irradiate the energy beam so that the time from the ejection of the droplet to the irradiation of the energy beam is the same at any position on the substrate. Thereby, the photocurable resin can be cured uniformly. When an ultraviolet curable resin is used as the photocurable resin, ultraviolet light may be used as the energy ray. Here, the “energy beam” is a concept including not only electromagnetic waves such as ultraviolet rays, but also X-rays, ions, and particle beams.
[0019]
Further, it is also possible to continuously apply a droplet and irradiate a light curable resin film on the photocurable resin film cured by energy ray irradiation, so that the photocurable resin is overcoated. The film thickness of the photocurable resin layer can be controlled to a desired value by repeatedly performing such overcoating of the photocurable resin. Such over-coating can also be applied to the formation of a recording layer formed using an organic dye or a lubricating layer formed using a lubricant. In this case, after the recording layer and the lubricating layer are appropriately dried, droplets for forming those layers may be ejected onto the dried layer.
[0020]
In the optical disc manufactured by the manufacturing method of the present invention, an annular bulge (projection) is not formed on the outer peripheral portion of the protective layer. Therefore, when a magneto-optical disk or a magnetic recording medium is manufactured, the magnetic head does not collide with the outer peripheral portion of the protective layer during recording and reproduction. Further, in the optical disc manufactured by the manufacturing method of the present invention, an area that could not be used as a recording area because of an annular protrusion on the outer periphery of the protective layer can be used as a recording area. The recording capacity of the optical disk can be increased as compared with the conventional case. In particular, it is desired to increase the recording / reproducing area in an optical disk having a small outer diameter, and an optical disk having an outer diameter smaller than 5.25 inches, for example, an outer diameter of 3.5 inches (89 mm) or 2.5 inches ( It is most suitable as a method for manufacturing a small optical disk such as 64 mm) or 2.0 inch (50 mm).
[0021]
Further, unlike the spin coating method, the manufacturing method of the present invention can form a thin film without rotating the substrate. That is, a thin film can be reliably formed even on a substrate that cannot be rotated. According to the manufacturing method of the present invention, a thin film can be formed on a substrate having an arbitrary shape. Further, a thin film can be formed in an arbitrary region on the substrate.
[0022]
According to a second aspect of the present invention, there is provided a recording medium manufactured by using the method for manufacturing a recording medium according to the first aspect. In the recording medium according to the present invention, a uniform and flat thin film layer is formed in a desired region on the substrate.
[0023]
In the present invention, it is preferable that the thin film is a protective layer formed of a resin. Further, the thin film may be a recording layer formed of an organic dye. Further, the thin film may be provided only in a part of the substrate.
[0024]
According to a third aspect of the present invention, there is provided an apparatus for manufacturing a recording medium including a thin film on a substrate,
A droplet ejecting head for ejecting droplets onto the substrate,
There is provided a manufacturing apparatus comprising: a relative moving unit configured to move the droplet ejecting head relative to the substrate.
[0025]
The manufacturing apparatus of the present invention controls the ejection amount, ejection cycle, and relative speed of the droplet ejection head by controlling the ejection amount of the droplet and the relative speed of the droplet ejection head, and continuously ejects the droplet onto the substrate to make it uniform on the substrate. Therefore, it is possible to easily and inexpensively manufacture a recording disk having a thin film having an extremely uniform thickness including the outer peripheral portion. Further, it is possible to easily and inexpensively manufacture a disk having a thin film having a uniform thickness only in a desired area on the disk.
[0026]
The droplet ejecting head of the manufacturing apparatus of the present invention uses, for example, a piezoelectric element (such as a piezo element) that is mechanically deformed by applying a voltage to extrude the liquid in the liquid chamber by changing the volume of the liquid chamber. It can be configured using a head having a function of ejecting the ink. Such a droplet ejecting head can regularly adhere droplets to a fine region on a substrate. Therefore, a film having high uniformity can be formed on the substrate. Further, since a thin film can be formed by attaching a droplet only to a necessary region on a substrate, the present invention is excellent in economical efficiency. As the head using the above-described piezoelectric element, for example, a piezoelectric element type ink jet head used in an ink jet printer can be used. In addition to the piezoelectric element type head, for example, a head that ejects droplets by concentrating an acoustic wave generated by the vibration of the piezoelectric element at a certain point on the surface to be coated with a concave lens-shaped acoustic lens may be used.
[0027]
The droplet ejection head may include a plurality of nozzles that eject droplets. In this case, the droplets can be deposited over a wide range, which is efficient. At this time, it is desirable that the nozzles are arranged so that the droplets ejected from the droplet ejection head and adhered to the substrate partially overlap.
[0028]
In the manufacturing apparatus of the present invention, as a relative moving means for relatively moving the droplet ejecting head with respect to the substrate, a head movement capable of moving the droplet ejecting head on the substrate in a predetermined direction parallel to the substrate surface An apparatus may be used. Further, the relative moving means may be configured by using a moving device capable of moving the substrate in a biaxial direction (X-Y direction) with respect to the fixed droplet ejecting head. Alternatively, a substrate moving device capable of moving the substrate in a predetermined direction (X direction) and a droplet ejecting head can be reciprocated on the substrate in a direction perpendicular to the X direction (Y direction). It may be constituted by a head moving device. In this case, a thin film can be formed on the substrate by moving the droplet ejecting head in the Y direction on the substrate and ejecting the droplets while moving the substrate in the X direction by the substrate moving device.
[0029]
When the substrate has a disk shape, the relative moving means may be configured using, for example, a rotation driving device for rotating the substrate around the center as a rotation axis. In this case, for example, using a head moving device capable of moving the droplet ejecting head in the radial direction of the substrate, while rotating the substrate with a rotary driving device, moving the droplet ejecting head from the inner peripheral side to the outer peripheral side of the substrate Alternatively, a thin film can be formed on a substrate by moving droplets from the outer peripheral side to the inner peripheral side to eject droplets. It is preferable that the rotation drive device controls the rotation speed such that the linear velocity of the region where the droplets are attached by the droplet ejection head is constant. In this case, the ejection amount and ejection cycle per droplet are fixed. Further, it is also possible to perform the application while keeping the angular velocity of the rotary drive device constant. In this case, the injection amount per injection or the injection period is changed according to the radial position of the substrate. In any case, control is performed so that the injection amount per unit area is equal at each position on the substrate. Thus, the droplets can be uniformly attached to the substrate surface.
[0030]
As the substrate moving device and the head moving device, for example, a feed screw driving type, a timing belt driving type, a linear motor driving type, and the like can be used. Alternatively, the droplet ejecting head may be provided at the tip of a swing arm connected to a rotary actuator, and the droplet ejecting head may be moved in a fan shape on the medium by rotating the rotary actuator.
[0031]
The manufacturing apparatus according to the present invention includes, for example, a light source for irradiating light to a region on the substrate to which the droplet has adhered when a solution of a photocurable resin for forming a protective layer is used as a material for the droplet. Can be provided. When the photocurable resin is an ultraviolet curable resin, an ultraviolet lamp can be used as a light source. In addition, in addition to the photocurable resin solution as the material of the droplets, for example, when using a thermosetting resin solution, an electron beam curable resin solution, an ultrasonic curable resin solution, the manufacturing apparatus is Each can include a heat source, an electron beam irradiation device, and an ultrasonic generator.
[0032]
In addition, the manufacturing apparatus of the present invention forms a recording layer of a write-once optical recording medium by using a solution containing an organic dye as a material of the droplet and ejecting a droplet of the solution containing the organic dye from a droplet ejecting head. can do. In this case, by controlling the size, position, and the like of the nozzle of the droplet jet head, the organic dye can be formed only in a desired region.
[0033]
According to a fourth aspect of the present invention, there is provided a method of manufacturing a recording medium comprising a thin film on a substrate,
Forming a thin film on a stamper used for manufacturing the recording medium by relatively moving a position for ejecting the droplet with respect to the stamper while ejecting a droplet containing a material constituting the thin film; When;
Attaching a substrate on the thin film formed on the stamper;
Separating the substrate to which the thin film is attached from the stamper. Thus, high-speed application of the resin is possible, and only a necessary amount of the resin can be applied to a necessary area.
[0034]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of a method and an apparatus for manufacturing a recording medium according to the present invention will be specifically described with reference to the drawings, but the present invention is not limited thereto.
[0035]
Embodiment 1
In the present embodiment, an example of manufacturing a magneto-optical disk using the manufacturing apparatus according to the present invention will be described. 1A and 1B show a schematic structure of a magneto-optical disk. FIG. 1B shows a layer configuration diagram of the magneto-optical disk 10 having the structure shown in FIG. The magneto-optical disk 10 has a first dielectric layer 2, a magneto-optical recording layer 3, a second dielectric layer 4, a reflective layer 5, and a protective layer 6 on a transparent substrate 1.
[0036]
As the transparent substrate 1, for example, a substrate obtained by molding a transparent resin material such as polycarbonate or amorphous polyolefin into a desired shape, or a desired preformat pattern is transferred to one surface of a glass plate formed into a desired shape. Any substrate having optical transparency, such as a substrate having a transparent resin film adhered thereto, can be used.
[0037]
The first dielectric layer 2 and the second dielectric layer 4 are layers for increasing the apparent Kerr rotation angle by causing a reproduction light beam to cause multiple interference in the film during reproduction, and have a refractive index higher than that of the substrate 1. Is large, for example, Si ₃ N ₄ It can be formed using an inorganic dielectric made of a compound.
[0038]
The magneto-optical recording layer 3 is a perpendicular magnetization film exhibiting perpendicular magnetic anisotropy at a temperature of room temperature or higher. For example, an amorphous alloy of a rare earth and a transition metal such as TbFeCo, DyFeCo, and TbDyFeCo is most preferable. Other known magneto-optical recording materials, such as an alternating layered structure of a Co film and a Co film or a garnet-based oxide magnetic material, can also be used.
[0039]
The reflection layer 5 is a layer for reflecting a reproducing light beam transmitted through the substrate 1, the first dielectric layer 2, the magneto-optical recording layer 3, and the second dielectric layer 4, and is made of Al, Ag, Au, or the like. A metal material having a high light reflectance or an alloy material such as an Al-Ti alloy can be used.
[0040]
The first dielectric layer 2, the magneto-optical recording layer 3, the second dielectric layer 4, and the reflective layer 5 can be formed by a dry process such as continuous sputtering using a magnetron sputtering device.
[0041]
The protective layer 6 protects the film laminated between the substrate 1 and the protective layer 6 from a chemical adverse effect such as corrosion, and is made of, for example, a resin film such as an ultraviolet curable resin. The protective layer 6 made of an ultraviolet curable resin is formed in the air or by using Ar or N ₂ Etc. in an inert gas atmosphere.
[0042]
The composition of the ultraviolet curable resin is mainly composed of a photopolymerizable oligomer, a reactive diluent, a photoinitiator, a photoinitiator, and other additives. As an ultraviolet curable resin used for a protective layer for an optical disk such as a magneto-optical disk, a resin whose viscosity, applicability (wetting property), adhesiveness, hardness and the like are adjusted in relation to the optical disk performance and the manufacturing process is commercially available. I have. For example, products such as a protective coating material “SD-17” manufactured by Dainippon Ink and Chemicals, Inc. can be used.
[0043]
〔manufacturing device〕
Here, the manufacturing apparatus according to the present invention, which is used when forming the protective layer, will be described. 2 and 3 schematically show the configuration of the manufacturing apparatus 100 used when forming the protective layer. FIG. 2 is a schematic configuration diagram of the manufacturing apparatus 100 when the droplet ejecting head is operating, and FIG. 3 is a schematic configuration diagram of the manufacturing apparatus 100 when the light irradiation device is operating. As shown in FIGS. 2 and 3, the manufacturing apparatus 100 includes a turntable 101 on which the substrate 1 is placed, a motor 102 for driving the turntable 101 to rotate, and a device for ejecting droplets onto the substrate 1. The apparatus mainly includes a liquid droplet ejecting head 103 (see FIG. 2), an ultraviolet irradiation device 112 (see FIG. 3) for irradiating ultraviolet light to a region on the substrate 1 on which liquid droplets are applied, and a control device 109.
[0044]
As shown in FIG. 2, the droplet ejection head 103 is provided at a lower end of the slide table 104 and is connected to a liquid tank 108 for supplying droplets. The liquid tank 108 is filled with the above-described solution for forming a protective layer. The slide table 104 is slidably engaged on a ball screw 105 extending from the vicinity of the center of the turntable 101 to the outer peripheral direction above the turntable 101. One end of the ball screw 105 is supported by a support portion 107 that rotatably supports the ball screw 105, and the other end of the ball screw 105 is connected to a motor 106. By driving the motor 106 to rotate the ball screw 105, the slide table 104 can be slid on the ball screw 105. The driving of the motor 106 is controlled by the control device 109. That is, the position of the droplet ejection head 103 moved by the slide table 104 in the radial direction of the substrate is controlled by the control device 109. In addition, the control device 109 controls the droplet ejection head 103 so as to set ejection conditions (such as an ejection amount per ejection and an ejection cycle) corresponding to the position as needed.
[0045]
Further, when the droplet jet head 103 is disposed on the substrate 1, as shown in FIG. 4A, a plurality of nozzles 103b of the droplet jet unit 103a are arranged in a radial direction of the substrate. It is configured. Alternatively, as shown in FIG. 4B, the droplet ejection head 103 'is configured such that the nozzles 103'b of the droplet ejection unit 103'a are arranged obliquely to the substrate radial direction. May be. The distance between the nozzle 103b of the droplet ejecting section 103a of the droplet ejecting head 103 and the substrate surface when the droplet ejecting head 103 is disposed on the substrate (from the lowermost surface of the droplet ejecting head 103 to the substrate surface). Distance) is about 0.5 mm to 10 mm. As shown in FIG. 5A, the droplet ejecting section 103a of the droplet ejecting head 103 has a structure in which an upper portion of a liquid chamber 103c is covered with a piezoelectric element 103d. In FIG. 5A, a nozzle 103b for discharging liquid droplets is formed on the right side wall of the liquid chamber 103c of the liquid droplet ejecting unit 103a, and the liquid tank shown in FIG. 2 is formed on the left side wall of the liquid chamber 103c. A supply port 103e for supplying a liquid from the gas chamber 108 or a manifold (not shown) to the liquid chamber 103c is formed. The principle of the droplet ejection of the droplet ejection unit 103a is as follows.
[0046]
As shown in FIG. 5A, before the liquid droplet is ejected, the liquid chamber 103c is filled with the liquid lq, and when a predetermined voltage is applied to the piezoelectric element 103d, the piezoelectric element 103d becomes “upwardly convex”. The liquid pressure wave is generated in the liquid chamber 103c. When a voltage of the opposite polarity is applied to the piezoelectric element 103d, the piezoelectric element 103d is deformed from “upwardly convex” to “downwardly convex” as shown in FIG. 5B. Thereby, the volume of the liquid chamber 103c decreases, and the pressure wave reaches the nozzle 103b, and the liquid lq in the liquid chamber 103c is pushed out to the nozzle 103b, and as shown in FIG. dl is emitted from the nozzle 103b. Further, when a voltage of the opposite polarity is applied, as shown in FIG. 5 (d), the piezoelectric element 103d becomes “upwardly convex” again, and the liquid lq is filled in the liquid chamber 103c and the pressure wave is increased. Occurs again. The detailed structure of such a liquid droplet ejecting unit 103a includes, for example, an upper electrode, a PZT, a lower electrode, a variable plate, a coating ink chamber plate, a communication plate, a stainless steel plate, and the like as shown in FIG. And an ink jet head for an ink jet printer such as an ML Chips head. The ejection and stop of the droplet can be controlled by the control device 109 shown in FIG. 2 by modulating the voltage waveform applied to the piezoelectric element.
[0047]
As shown in FIG. 3, the ultraviolet irradiation device 112 includes an ultraviolet lamp 113 and an arm (not shown) that supports the ultraviolet lamp 113, and starts ultraviolet irradiation after the above-described droplet ejection ends. . The ultraviolet irradiation may be performed after all the droplets are applied to a predetermined portion on the substrate, but may be performed as needed from the portion where the application by the droplet ejection is completed. In addition, as shown in FIG. 3, a plurality of ultraviolet lamps 113 may be provided above the surface of the substrate on which the liquid droplets are applied, or only one ultraviolet lamp may be provided above the center of the substrate.
[0048]
[Operation of manufacturing equipment]
Next, the operation of the manufacturing apparatus 100 will be described below with reference to FIG. First, as shown in FIG. 7 (a), a spindle 110 provided in a central portion of a turntable 101 of a control device 100 is inserted into a spindle hole 1a of a substrate 1 on which a layer such as a recording layer is formed. The substrate 1 is placed on the substrate 101, and the substrate 1 is fixed by the fixing jig 111. The manufacturing apparatus 100 drives the motor 106 to move the slide table 104 until the droplet ejection head 103 is located immediately above the ejection start position on the inner circumference of the substrate 1. Next, a turntable driving motor (not shown) is driven to rotate the turntable 101 to rotate the substrate 1 with respect to the droplet ejecting head 103, and the droplet ejecting head 103 moves the liquid onto the substrate 1. Inject drops. As shown in FIG. 7B, the control device (not shown) controls the slide table 104 to gradually move outward in the radial direction of the substrate 1 (arrow AR7) with the rotation of the turntable 101. . Thereby, a coating film can be formed on the substrate with a uniform film thickness.
[0049]
Further, the control device controls the slide table 104 to move outward in the radial direction of the substrate 1 by a distance corresponding to the application width of the droplet ejecting head 103 in the substrate radial direction each time the turntable 101 rotates once. May be. Thereby, a coating film can be formed on the substrate with a uniform film thickness.
[0050]
Here, the state of droplets attached to the substrate by droplet ejection by the droplet ejection head 103 will be described with reference to FIGS. 8 and 9. FIG. 8 is a diagram schematically illustrating a state in which the droplet ejecting head 103 ejects a droplet to a predetermined position on the substrate 1. FIG. 9 is an enlarged schematic view of the portion indicated by S2 in FIG. 8, and conceptually shows the state of the droplet applied on the substrate 1. As shown in FIG. 9, the droplet 6 ′ a attached to the substrate 1 immediately after the droplet ejection by the droplet ejection head 103 rises, but the droplet 6 ′ b after a predetermined time elapses. It flows together and forms a flat coating film. The intervals between the droplets adhering to the substrate 1 include the position of the nozzle of the droplet ejection head, the distance between the nozzle (the lowermost surface of the droplet ejection head) and the substrate surface, the volume (capacity) of the droplet, and the It changes according to parameters such as viscosity, environmental temperature, and substrate rotation speed. Therefore, in order to prevent the surface of the substrate from being exposed between the droplets adhering to the substrate, the droplets are repeatedly ejected by the droplet ejecting head while changing the above parameters, and the obtained parameters are obtained for each parameter. The above parameters can be finally determined based on the result. The rotation speed of the substrate and the conditions for spray coating are as follows.
[0051]
The rotation speed of the substrate is controlled by the droplet ejection head so that the linear velocity of the region where the droplets adhere is constant. The spray application conditions at this time are such that the ejection amount per droplet and the ejection cycle are constant. Further, it is also possible to control the rotation speed of the substrate so that the angular speed becomes constant. The spray application conditions at this time change the amount of injection or the injection cycle per one time according to the radial position of the substrate. In any case, control is performed so that the injection amount per unit area is equal at each position on the substrate. Thus, the droplets can be uniformly attached to the substrate surface.
[0052]
Next, as shown in FIG. 7C, after forming a resin coating film 6 ′ by the droplet jet head 103, the ultraviolet lamp 113 is positioned on the substrate as shown in FIG. 7D. Then, by irradiating ultraviolet rays for a predetermined time, the coating film of the resin formed on the substrate 1 is cured, and the protective layer 6 of the ultraviolet curing resin can be formed on the substrate 1.
[0053]
[Manufacture of magneto-optical disks]
Next, a method for manufacturing a magneto-optical disk having the structure shown in FIG. 1 will be described. As the substrate 1, a transparent polycarbonate resin substrate having a preformat pattern on one side is used. The substrate 1 has a diameter of 120 mm and a thickness of 1.2 mm. On the surface of the substrate 1 on which the preformat pattern has been formed, a first dielectric layer 2 made of a SiN compound film, ₂₁ Fe ₆₆ Co _Thirteen A magneto-optical recording layer 3 made of an amorphous alloy, a second dielectric layer 4 made of a SiN compound film, and a reflective layer 5 made of an aluminum-titanium (AlTi) alloy film are sequentially formed by a sputtering method. The magneto-optical recording layer 3 can be formed, for example, in a range of 39 mm to 119 mm in diameter on the substrate. Table 1 shows the film thickness of the magneto-optical recording layer 3 and the Curie temperature Tc.
[0054]
[Table 1]

[0055]
Next, the protective layer 6 is formed on the reflective layer 5 by using the manufacturing apparatus 100 shown in FIGS. The thickness of the protective layer 6 can be selected from the range of 2 to 20 μm, and particularly preferably, is selected from the range of 5 to 15 μm. By forming the protective layer 6 according to the operation of the manufacturing apparatus described above, the unevenness on the surface of the protective layer 6 is 5 to 10 μm or less on average from the inner periphery to the outer periphery, and a flat protective layer can be obtained. Further, since no annular protrusion is formed on the outer peripheral portion of the protective layer, the magnetic head 61 can be floated at a constant height also on the outer peripheral portion of the magneto-optical disk 10 as shown in FIG. it can. An area of the magneto-optical recording layer 3 having a diameter of 40 mm to 118 mm can be used as a recording area, and a wide effective recording area can be secured.
[0056]
[Recording and playback of information]
The magneto-optical disk 10 manufactured as described above is suitable for a magnetic field modulation recording method in which the magnetic head needs to be brought close to the recording layer because the thickness of the protective layer is uniform in the disk surface as described above. is there. An example will be described below. Recording and reproduction were performed at a linear velocity of 7.5 m / s using an optical pickup having a laser wavelength of 780 nm and a lens numerical aperture (NA) of 0.55. At the time of recording, an external magnetic field modulated according to information to be recorded was applied while irradiating a laser beam in a pulse shape. The laser power was 12 mW in peak value and the duty ratio was 50%. The external magnetic field was modulated at ± 200 Oe. A continuous repeating pattern having a length of 0.7 μm was recorded and reproduced with a laser power of 1.5 mW to obtain a CN ratio of 45 dB or more. It is to be noted that an optical modulation recording method can be used for this disc.
[0057]
Embodiment 2
In the present embodiment, a method for forming the protective layer 6 of the magneto-optical disk 10 shown in FIG. 1 by driving the droplet ejecting head 103 and the ultraviolet irradiation device 112 of the manufacturing apparatus 100 in Embodiment 1 in parallel is described. This will be described with reference to FIGS.
[0058]
First, the substrate 1 is rotated by the turntable 101, and the droplet ejection head 103 is positioned directly above the ejection start position on the inner peripheral side of the substrate 1. Then, as shown in FIG. 10, the droplet ejecting head 103 is moved from the inner peripheral side to the outer peripheral side at a predetermined pitch while ejecting the droplet onto the substrate 1 by the droplet ejecting head 103 (arrow AR10a). . Next, after a predetermined time has elapsed from the start of the droplet ejection by the droplet ejection head 103, the ultraviolet irradiation device 112 is driven to position the ultraviolet lamp 113 on the inner peripheral side of the substrate 1. Then, as shown in FIGS. 10 and 11, the ultraviolet lamp 113 is moved from the inner peripheral side to the outer peripheral side of the substrate 1 (arrow AR10b), and the coating film of the resin liquid formed on the substrate 1 by the droplet ejecting head 103 is formed. 6 ′ is cured (protective layer 6). As described above, in the method in which the droplet ejection by the droplet ejection head 103 and the ultraviolet irradiation by the ultraviolet irradiation device 112 are performed in parallel, the protective layer can be formed on the substrate in a short time, so that the productivity is excellent. .
[0059]
Embodiment 3
In this embodiment, a method for forming the protective layer 6 of the magneto-optical disk 10 shown in FIG. 1 using a manufacturing apparatus 200 as shown in FIGS. 12 and 13 will be described. FIG. 13 is a diagram showing a cross section taken along line XX ′ of FIG. In FIG. 13, the right part of the ball screw 205 and the motor 206 are omitted for convenience. The manufacturing apparatus 200 shown in FIG. 12 has a ball screw 205 having a length longer than the diameter of the substrate, and the slide table 204 on which the droplet ejecting head 203 is mounted is mounted on one side of the substrate in the diameter direction of the substrate. It is movable from the outer peripheral end to the other outer peripheral end, and has the same structure as the manufacturing apparatus 100 of the first embodiment except that the moving direction of the droplet jet head 203 and the moving direction of the ultraviolet irradiation device 212 are orthogonal. ing. The operation of the manufacturing apparatus 200 will be described below.
[0060]
First, the substrate 1 is rotated by a turntable. Next, as shown in FIG. 12A, the slide table 204 on which the droplet ejection head 203 is mounted and the ultraviolet lamp 213 are positioned just above the outer peripheral edge of the substrate 1. Then, the droplet ejection head 203 starts ejecting droplets from the outer peripheral side of the substrate 1 and moves the droplet ejection head 203 at a predetermined pitch toward the center of the substrate (arrow AR12a). After a predetermined time has elapsed from the ejection of the droplet, the ultraviolet irradiation device 212 is driven to move the ultraviolet lamp 213 from the outer peripheral side of the substrate toward the center while irradiating the ultraviolet light with the ultraviolet lamp 213 (arrow AR12b). ). In this way, the ejection of liquid droplets from the outer peripheral side of the substrate 1 and the curing of the coating film of the resin liquid by ultraviolet irradiation are performed in parallel.
[0061]
When the droplet ejecting head 203 is positioned at the inner peripheral end of the substrate 1 and a coating film of the resin liquid is formed on the substrate 1, the ejection of the droplets from the droplet ejecting head 203 is temporarily stopped. Further, the ultraviolet lamp 213 is positioned at the inner peripheral end of the substrate 1, and the coating film of the resin liquid formed on the substrate is cured to form a protective layer. Here, the ultraviolet irradiation by the ultraviolet lamp 213 is also temporarily stopped.
[0062]
Next, as shown in FIGS. 12 (b) and 13 (a), when the droplet ejecting head 203 further moves beyond the center of the substrate 1 and is positioned at the inner peripheral end of the substrate 1, the liquid is ejected. The droplet ejection head 203 starts ejecting droplets again, and the droplet ejection head 203 is moved from the inner peripheral side to the outer peripheral side of the substrate 1 (arrow AR12c), and the liquid is ejected onto the protective layer 6 formed by the above method. The droplets are further adhered to form a coating film 6 'of the resin liquid. Then, as shown in FIGS. 13 (a) and 13 (b), the ultraviolet irradiation device 212 is driven to irradiate the coating film 6 ′ of the resin liquid formed on the inner peripheral side of the substrate with ultraviolet light by the ultraviolet lamp 213. The ultraviolet lamp 213 is moved from the inner peripheral side to the outer peripheral side (arrow AR12d). Thus, another protective layer 6 can be laminated on the protective layer 6. According to such a forming method, for example, a first protective layer is formed to a thickness of 10 μm, and a 20 μm protective layer is laminated thereon as a second layer to form a protective layer having a thickness of about 30 μm. You can also.
[0063]
In addition, by repeating the above operation, a protective layer can be formed in multiple layers. As a result, the thickness of the protective layer can be increased. For example, a protective layer having a desired thickness of 100 μm or more can be formed. The protective layer obtained by such a method has a flat surface and a uniform thickness.
[0064]
Embodiment 4
In the present embodiment, a method for forming the protective layer 6 of the magneto-optical disk 10 shown in FIG. 1 using a manufacturing apparatus 300 as shown in FIGS. 14 and 15 will be described. As shown in FIGS. 14 and 15, the manufacturing apparatus 300 mainly includes a ball screw 305, a droplet jet head 303, a motor 306, a support unit 307, and a substrate mounting table 301. The droplet ejection head 303 is provided at the lower end of the slide table 304 as shown in FIG. The slide table 304 is slidably engaged on a ball screw 305 extending in the diameter direction of the substrate mounting table 301. The length of the ball screw 305 is longer than the diameter of the substrate mounting table 301, and one end of the ball screw 305 is supported by a support portion 307 that rotatably supports the ball screw 305, and the other end of the ball screw 305. The end is rotatably connected to the motor 306. By driving the motor 306 to rotate the ball screw 305, the slide table 304 can be slid on the ball screw 305. The position of the droplet ejection head 303 moved by the slide table 304 in the substrate diameter direction is controlled by controlling the driving of the motor 306 by the control device 309. The droplet ejection head 303 has a plurality of nozzles, and each nozzle is arranged side by side in a direction (vertical direction in FIG. 14) perpendicular to the moving direction of the slide table 304 (horizontal direction in FIG. 14). I have. Further, a solution containing an ultraviolet curable resin is supplied to the droplet jetting head 303 from a liquid tank (not shown). The substrate mounting table 301 can be moved by a transfer device (not shown) at a predetermined pitch in a direction perpendicular to the moving direction of the slide table 304 (vertical direction in FIG. 14) (arrow AR14). Further, as shown in FIG. 15, a columnar projection 310 is formed on the substrate mounting table 301, and when the substrate 1 is mounted on the substrate mounting table 301, the columnar projection 310 is formed. Is inserted into a spindle hole 1a at the center of the substrate 1 and functions as a spindle for suppressing the movement (displacement) and vibration of the substrate 1.
[0065]
Hereinafter, the operation of the manufacturing apparatus 300 will be described. By the movement of the substrate mounting table 301, the substrate 1 is moved so that the outer peripheral end 1b of the substrate 1 in the moving direction of the substrate mounting table 301 (vertical direction in FIG. 14) is directly below the moving axis of the droplet ejecting head 303. Position. Next, the motor 306 is driven to slide the droplet ejecting head 303 from the support 307 side to the motor 306 side, for example, so that the droplet ejecting head 303 crosses the substrate 1. At this time, the droplet ejection of the droplet ejection head 303 is controlled so that the droplets from the droplet ejection head 303 adhere to a predetermined region of the substrate 1. Then, when the droplet ejection head 303 moves to the motor 306 side, the transport device (not shown) is driven to move the substrate mounting table 301 at a predetermined pitch in the upward direction in the drawing (the direction of the arrow AR14). Next, while moving the droplet ejection head 303 from the motor 306 side to the support portion 307 side, the droplet ejection head 303 ejects droplets only when the droplet ejection head 303 scans over the substrate 1, A droplet is adhered to a predetermined region on 1 to form a resin film 6 ′. When the droplet ejecting head 303 moves to the support section 307 side, the substrate 1 is moved upward at a predetermined pitch by the movement of the substrate mounting table 301 (arrow AR14). The protective layer can be formed on the substrate 1 by repeatedly performing this operation to form the coating film 6 ′ of the resin liquid on the substrate 1.
[0066]
In the above operation, when the droplet ejecting head 303 crosses over a region on the substrate 1 where the protective layer is not formed, for example, over the non-coating region 1c including the spindle hole 1a, a droplet is deposited on the non-coating region 1c of the substrate 1. Control not to be injected.
[0067]
In this embodiment, the thickness, shape, material, and the like of the substrate 1 are not limited, and any substrate can be used. In addition, it is also possible to divide a region for ejecting liquid droplets on the substrate in advance into a number of independent regions and scan the independent regions in order with a droplet ejecting head to eject droplets. .
[0068]
Embodiment 5
In this example, a write-once compact disc (CD-R) was manufactured using the manufacturing apparatus 400 shown in FIG. 16 as the manufacturing apparatus according to the present invention. As shown in FIG. 16, the manufacturing apparatus 400 mainly includes a rotary actuator 407, a swing arm 405, a droplet ejection head 403, and a control device 409. The droplet ejection head 403 is attached to the tip of the swing arm 405. The swing arm 405 moves in a fan shape about the central axis of the rotary actuator 407, and thereby the droplet ejecting head 403 can be positioned at a predetermined position on the substrate. The substrate 11 is mounted on a turntable (not shown) rotatable by a rotation motor (not shown), and is rotatable in a direction of an arrow AR16 in FIG. The control device 409 controls the distance between the droplet ejection head 403 and the surface of the substrate 11, the amount of droplet ejection from the droplet ejection head 403, the ejection time of the droplet, the amount of movement of the droplet ejection head 403, and the like. Can be. Further, when the droplet ejecting head 403 is positioned on the substrate 11, the control device 409 controls the substrate 11 so that the linear velocity or the angular velocity of the substrate 11 at a position immediately below the droplet ejecting head 403 is always constant. The number of rotations can be controlled. The droplet ejection was controlled in the same manner as in Example 1.
[0069]
By using the manufacturing apparatus 400, a write-once compact disc can be manufactured. As shown in FIG. 17, the write-once compact disc includes a recording layer 13, a light reflection layer 15, and a first protective layer 16 on a substrate 11, and the recording surface of the substrate 11 on which the recording layer 13 and the like are formed. It has a structure provided with a second protective layer 17 on the opposite surface. The recording layer 13 is an organic dye film containing a phthalocyanine dye as a main component.
[0070]
As the substrate 11, a transparent polycarbonate resin substrate having a thickness of 1.2 mm and a diameter of 120 mm and having good optical characteristics was used. One surface of the substrate 11 has an uneven preformat pattern. The substrate 11 is mounted on the manufacturing apparatus 400 shown in FIG. 16 such that the surface on which the preformat pattern is formed faces upward. First, the rotary actuator 407 is driven to position the droplet ejection head 403 on the outer peripheral side of the substrate 11. The substrate 11 is rotated, and droplets mainly containing a phthalocyanine organic dye are ejected from the droplet ejecting head 403 onto the surface of the substrate 11 on which the preformat pattern is formed, and droplets are ejected by rotation of the rotary actuator 407. The head 403 is moved at a predetermined pitch toward the inner peripheral side of the substrate 11. At this time, the control device 409 controlled the rotation speed of a rotation motor (not shown) so that the linear velocity of the substrate 11 at a position immediately below the droplet ejection head 403 was constant. Thus, a thin film containing a phthalocyanine organic dye as a main component was formed on the substrate 11. Then, by drying the obtained thin film, a recording layer 13 containing a phthalocyanine organic dye as a main component was formed.
[0071]
Here, as the material for the droplets, a solution containing a phthalocyanine organic dye as a main component was used, but a solution containing an organic phthalocyanine dye, an organic solvent, and an additive, or an arbitrary solution such as a cyanine organic dye or an azo dye is used. May be used.
[0072]
Next, the light reflection layer 15 made of Au was formed on the recording layer 13 by a plasma deposition method or a sputtering method. Next, a first protective layer 16 and a second protective layer 17 made of an ultraviolet curable resin are formed on the light reflection layer 15 made of Au and on the surface of the substrate 11 opposite to the surface on which the preformat pattern is formed. Form. The first and second protective layers 16 and 17 can be formed using the manufacturing apparatus 400 shown in FIG. In this case, an ultraviolet curable resin is used as a material of the droplet. A layer made of an ultraviolet curable resin can be formed in the same manner as the formation of the recording layer 13. The substrate on which the ultraviolet curable resin layer is formed is mounted on a manufacturing apparatus having an ultraviolet irradiation device 112 as shown in FIG. The ultraviolet curable resin layer is irradiated with ultraviolet light to cure the ultraviolet curable resin layer using such a manufacturing apparatus. Thus, the first protective layer 16 and the second protective layer 17 made of an ultraviolet curable resin are respectively formed on the light reflecting layer 15 made of Au and on the surface of the substrate 11 opposite to the surface on which the preformat pattern is formed. Was formed. These protective layers are formed, for example, with a thickness of about 10 μm. Thus, a write-once compact disc (CD-R) was produced.
[0073]
In particular, the production method of the present invention is suitable for forming a desired coating film only on a part of the substrate. FIG. 22 shows an example. In a medium 50 in which a read-only information (ROM) area 51 and a recordable (R) area 52 are mixed, that is, a so-called partial ROM disk, when a relatively small recordable area 52 is sufficient, an organic dye is applied only to a necessary portion thereof. What is necessary is just to apply and secure the additional recordable area 52. At this time, if the conventional spin coating method is used, the application area cannot be accurately controlled, and the read-only information area and the recordable area cannot be accurately separated. By applying the present invention, it is possible to apply an organic dye only to a necessary area with high accuracy. In particular, it is possible to apply it only to the inner peripheral portion, or to apply it to any shape and range.
[0074]
Embodiment 6
In the present embodiment, a compact disc having a diameter of 120 mm is manufactured using the manufacturing apparatus 100 in the first embodiment. The compact disk has a reflective layer 25 and a protective layer 26 on a transparent substrate 21, as shown in FIG. A polycarbonate resin substrate is used for the transparent substrate 21, and a preformat pattern is formed on one surface of the resin substrate 21. The transparent substrate 21 has a diameter of 120 mm and a thickness of 1.2 mm. The protective layer 26 is a layer for preventing the reflective layer 25 formed between the transparent substrate 21 and the protective layer 26 from a chemical change such as corrosion. A light-transmitting material that does not pass through, for example, a material such as an ultraviolet curable resin is used. The reflective layer 25 is formed of Al using a magnetron sputtering apparatus.
[0075]
The protective layer 26 can be formed by using the ultraviolet curing resin as a material by the manufacturing apparatus 100 in the first embodiment. That is, droplets of an ultraviolet curable resin are adhered on the reflective layer 25 using the liquid droplet jet head 103 shown in FIG. 2, and a coating film of the ultraviolet curable resin is formed on the reflective layer 25. Next, the protective layer 26 is formed by irradiating the ultraviolet curable resin coating film with ultraviolet rays to cure it using the ultraviolet irradiation device 112 shown in FIG. Thus, a compact disc having the laminated structure shown in FIG. 18 can be manufactured.
[0076]
As described above, the manufacturing method and the manufacturing apparatus of the present invention have been specifically described with reference to the examples, but the present invention is not limited to these. For example, in the above embodiment, a magneto-optical disk, a write-once compact disk (CD-R) and a compact disk were manufactured as recording media, but a phase-change optical recording medium, a mini disk (MD), and a laminated optical recording medium were used. Any recording medium such as a medium can be manufactured. Further, in the above-described embodiment, the protective layer made of the ultraviolet curable resin and the recording layer made of the organic dye were formed using the liquid droplet ejecting head. In the medium, an adhesive used for bonding the media can also be formed. Each of the liquids to be applied in accordance with each of these purposes can be applied by any method using the manufacturing apparatus having various structures described in Examples 1 to 5, and is limited to the combination of Examples. Not something. In addition, ultraviolet irradiation can be selectively performed as needed.
[0077]
Further, the present invention can be applied to a replication process for forming a preformat pattern on a substrate. In order to apply the present invention to this step, (1) first, an ultraviolet curable resin is filled in the manufacturing apparatus of the present invention having a droplet jet head. Next, (2) the ultraviolet curable resin is uniformly applied to a desired area on the stamper by the manufacturing apparatus, and (3) a substrate such as glass is pressed onto the applied ultraviolet curable resin and adhered. Next, (4) the ultraviolet curable resin is cured by irradiation with ultraviolet light, and (5) the cured ultraviolet curable resin is peeled off together with the substrate from the stamper. Through the above process, the resin can be applied at a high speed and the required amount of the resin can be applied only to the required area. Therefore, the resin does not protrude and the wiping step is not required. These methods can also be used when forming a preformatted surface on a multi-layer recording optical disc such as a two-layer DVD, so that the productivity of the multi-layer recording optical disc can be improved.
[0078]
【The invention's effect】
The production method of the present invention is capable of uniformly adhering liquid materials such as an ultraviolet curable resin solution, an organic dye solution, a lubricant, an adhesive, etc. to a substrate in the form of fine liquid droplets. Can be uniformly and flatly formed on the substrate. Therefore, it is optimal as a manufacturing method for manufacturing a recording medium including a protective layer made of an ultraviolet curable resin, a recording layer made of an organic dye, a lubricant layer made of a lubricant, and an adhesive layer made of an adhesive. Further, in the manufacturing method of the present invention, unlike the case where the spin coating method is used, an annular protrusion is not formed on the outer peripheral portion of the protective layer, so that the obtained recording medium has a recordable area as compared with the conventional medium. And the recording capacity can be increased.
[0079]
Further, in the manufacturing method of the present invention, since the substrate does not always need to be rotated, a thin film can be formed even on a substrate having a shape that could not be formed by the spin coating method. Further, in the present invention, a coating film can be further formed on the coating film formed by spraying the droplets, so that the occurrence of pinholes in the coating film can be prevented. In addition, since the formation of the coating film by spraying the droplets and the curing of the coating film by irradiation with ultraviolet rays can be performed in parallel, the production efficiency of the recording medium can be improved.
[0080]
The manufacturing apparatus of the present invention can form the liquid material uniformly and flatly on the substrate by the droplet ejecting head, so that the manufacturing method of the present invention can be realized. In addition, the manufacturing apparatus of the present invention ejects droplets only to a desired region on the substrate by the droplet ejecting head to form a thin film, so that no extra material is generated and it is extremely economical.
[0081]
Further, since the manufacturing apparatus of the present invention can eject droplets to a minute region on the substrate by the droplet ejecting head, a thin film can be partially formed in a desired region on the substrate. In addition, the manufacturing apparatus of the present invention can position a droplet ejecting head at an arbitrary region on the substrate and eject droplets, so that a thin film can be formed at any place on the substrate. When the recording layer is formed using a solution containing an organic dye, the solution containing the organic dye can be applied only to a predetermined area such as a recordable area of a partial ROM disk.
[0082]
Furthermore, the manufacturing method of the present invention enables high-speed application of resin, and also enables application of only a required amount of resin to a required area, thereby solving the problems related to resin application in the glass 2P method. Thus, the production efficiency of the recording medium can be improved.
[Brief description of the drawings]
1A is a schematic cross-sectional view of a magneto-optical disk manufactured in Example 1, and FIG. 1B is a diagram of a laminated structure of the magneto-optical disk, and FIG. 2) is a partially enlarged sectional view of a region S3 shown in FIG.
FIG. 2 is a schematic configuration diagram of a manufacturing apparatus according to the present invention used in Embodiment 1, and shows a state in which a droplet ejection head is driven.
FIG. 3 is a schematic configuration diagram of a manufacturing apparatus according to the present invention used in Embodiment 1, and shows a state in which an ultraviolet irradiation device is driven.
4A and 4B are diagrams showing an arrangement of nozzles of a droplet ejecting unit of the droplet ejecting head. FIG. 4A shows a state where the nozzles are arranged side by side in a substrate radial direction, and FIG. Indicates that nozzles are arranged obliquely with respect to the substrate radial direction.
FIG. 5 is a diagram for explaining the principle of ejecting droplets from a droplet ejecting unit.
FIG. 6A is a perspective view schematically showing a structure of a droplet ejection head used in the manufacturing apparatus of Example 1, and FIG. 6B is a perspective view of FIG. It is the figure seen from the front direction (A direction), and Drawing 6 (c) is the figure which looked at Drawing 6 (a) from the side direction (B direction).
7A and 7B are views for explaining a step of forming a protective layer on a substrate using the manufacturing apparatus according to the present invention. FIG. 7A shows a step of starting droplet ejection, and FIG. 7) shows a step in which droplet ejection is performed, FIG. 7C shows a step in which droplet ejection is completed, and FIG. 7D shows a step of irradiating ultraviolet rays.
FIG. 8 is a diagram illustrating a state in which a droplet ejection head is driven to eject droplets onto a substrate.
FIG. 9 is a partially enlarged view of a region S2 shown in FIG. 8 for explaining a state of a droplet adhered on a substrate by a droplet ejection head.
FIG. 10 is a diagram for explaining a method of driving the droplet ejecting head and the ultraviolet irradiation device in parallel, and is a conceptual diagram when an ultraviolet lamp is positioned on the inner peripheral side of the substrate.
FIG. 11 is a diagram for explaining a method of driving the droplet ejecting head and the ultraviolet irradiation device in parallel, and is a conceptual diagram when the ultraviolet lamp is positioned on the outer peripheral side of the substrate.
FIG. 12 is a schematic plan view of a manufacturing apparatus according to the present invention used in Embodiment 3, and FIG. 12 (a) shows a state where a droplet ejecting head and an ultraviolet lamp are positioned immediately above an outer peripheral portion of a substrate. FIG. 12B shows a state in which a protective layer is further formed on the formed protective layer.
13 (a) is a cross-sectional view taken along line XX ′ of the manufacturing apparatus shown in FIG. 12 (b), and FIG. 13 (b) is a view showing the manufacturing when the overcoating of the protective layer is completed. It is a schematic sectional drawing of an apparatus.
FIG. 14 is a schematic plan view of a manufacturing apparatus according to the present invention used in Example 4.
FIG. 15 is a schematic sectional view of the manufacturing apparatus shown in FIG.
FIG. 16 is a schematic plan view of a manufacturing apparatus according to the present invention used in Example 5.
FIG. 17 is a diagram showing a laminated structure of a write-once compact disc manufactured in Example 5.
FIG. 18 is a diagram showing a laminated structure of a compact disk manufactured in Example 5.
19A and 19B are diagrams for explaining a spin coating method. FIG. 19A shows a state where a coating liquid is placed on a substrate, FIG. 19B shows a state where the substrate is rotated, and FIG. FIG. 19D shows a state in which the rotation of the substrate has been completed, and FIG. 19D shows a state in which ultraviolet light has been irradiated.
FIG. 20 (a) is a schematic sectional view of a conventional magneto-optical recording medium, and FIG. 20 (b) shows a magnetic head moving on the medium and a raised portion of an outer peripheral portion of a protective layer. FIG. 21 is a partially enlarged sectional view of a region S3 shown in FIG. 20A conceptually showing a relationship.
21 (a) and 21 (b) are a schematic plan view and a schematic cross-sectional view, respectively, of a conventional magneto-optical recording medium, and FIG. 21 (c) is shown in FIG. 21 (b). It is the elements on larger scale sectional drawing of area | region S4 shown.
FIG. 22 is a schematic view of a partial ROM disk.
FIG. 23 is a schematic sectional view of a two-layer DVD.
[Explanation of symbols]
1,31 substrate
2,32 First dielectric layer
3,33 magneto-optical recording layer
4,34 second dielectric layer
5,35 reflective layer
6,36 protective layer
10 Magneto-optical disk
60 Optical head
61 Magnetic Head
74 translucent layer
75 Reflective layer
76 Protective layer
77 First Preformat Surface
78 Second preformat side
100, 200, 300, 400 Manufacturing equipment
103 droplet ejection head
104 slide table
109 control device
112,212 UV irradiation device
113,213 UV lamp
114,214 arm
115,215 Support
1a, 11a, 31a Spindle hole

Claims (16)

A method for manufacturing a recording medium including a thin film on a substrate,
Forming the thin film by relatively moving a position where the droplet is sprayed with respect to the substrate while spraying a droplet including a material constituting the thin film on the substrate. Manufacturing method of recording medium. The method according to claim 1, wherein the thin film is a recording layer, and the droplet contains an organic dye. The method according to claim 1, wherein the thin film is a protective layer, and the droplet contains a photocurable resin. The method according to claim 3, further comprising irradiating the droplet ejected onto the substrate with an energy beam to cure the droplet. The method according to claim 3, wherein the photocurable resin is an ultraviolet curable resin, and the energy rays are ultraviolet rays. A recording medium manufactured by using the manufacturing method according to claim 1. 7. The recording medium according to claim 6, wherein the thin film is a protective layer formed of a resin. The recording medium according to claim 6, wherein the thin film is a recording layer formed of an organic dye. 7. The recording medium according to claim 6, wherein the thin film is provided only in a partial area of the substrate. An apparatus for manufacturing a recording medium including a thin film on a substrate,
A droplet ejecting head for ejecting droplets onto the substrate,
A manufacturing apparatus comprising: a relative moving unit configured to move the droplet ejecting head relative to the substrate. 11. The manufacturing apparatus according to claim 10, wherein the droplet ejection head has a plurality of ejection ports for ejecting droplets. 12. The apparatus according to claim 10, wherein the relative moving means includes a head moving device for moving the droplet ejecting head on the substrate in a plane parallel to the substrate surface. The apparatus according to claim 10, wherein the relative moving unit further includes a substrate moving device for moving the substrate in a plane parallel to a substrate surface. 14. The manufacturing apparatus according to claim 10, wherein the substrate is a disk-shaped substrate, and the relative moving unit includes a rotation driving device for rotating the substrate. The apparatus according to any one of claims 10 to 14, further comprising an arm for supporting the droplet ejecting head. A method for manufacturing a recording medium including a thin film on a substrate,
Forming a thin film on a stamper used for manufacturing the recording medium by relatively moving a position for ejecting the droplet with respect to the stamper while ejecting a droplet containing a material constituting the thin film; When;
Attaching a substrate on the thin film formed on the stamper;
Separating the substrate to which the thin film has been attached from the stamper.

Images