JPH1139719A - Optical recording medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To cover an appearance defect due to bubbles, etc., remaining in an adhesive by facing a protective layer surface with a solidly printed surface of a dummy substrate and sticking them to each other. SOLUTION: A recording substrate laminating a recording layer, a reflection layer and a protective layer on a disk like transparent substrate is stuck to a dummy substrate solidly printed on the substrate one side surface by an adhesive so that the protective layer surface of the recording substrate is confronted with the solidly printed surface of the dummy substrate. When they are stuck to each other, the printing is performed so that the reflection layer is covered over the whole surface or a part of the reflection layer is not covered or is viewed e.g. annularly from the dummy substrate side. As the adhesive, ultraviolet setting adhesive is used from view points of workability and productivity. At a sticking time, when any substrate transmits ultraviolet rays through, after the substrates are overlapped through the adhesive, the adhesive is set by ultraviolet irradiation passing through the substrate. An ink receptive layer is preferably provided on the whole surface or the partial surface of the dummy substrate surface.

Description

【発明の詳細な説明】DETAILED DESCRIPTION OF THE INVENTION

【０００１】[0001]

【発明の属する技術分野】本発明は、大容量光記録媒
体、特に情報の記録、再生及び消去のうち、少なくとも
一つ以上が可能な全面貼り合わせ型の光記録媒体に関す
る。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a large-capacity optical recording medium, and more particularly to an optical recording medium of the entire surface type capable of at least one of recording, reproducing and erasing of information.

【０００２】[0002]

【従来技術】レーザービームを用いる光ディスクは、大
容量メモリーとして既にいくつか実用化されている。し
かし、情報量の増加により更に大きな記録容量を有する
光ディスクの開発が望まれて、記録容量を大きくする方
法が種々開発されている。例えば、記録容量は記録及び
又は再生する際のレーザービーム径に反比例するので、
短波長のレーザーや高ＮＡの対物レンズを用いることに
よりビーム径を小さくする方法が提案されている。高Ｎ
Ａの対物レンズを用いた場合、基板の変形による収差が
大きくなる。この問題は、基板の厚さを薄く、例えば、
0.6mm 程度にすることによって回避できる。しかし、基
板の厚さを薄くすると媒体の機械的強度が低下するため
に、２枚の基板を全面にわたり貼り合わせた媒体が提案
されている。例えば、記録可能光記録媒体としては、
０．６ｍｍの基板に記録層、反射層を積層した基板とダ
ミー基板を反射層を内側にして接着した貼り合わせ媒体
である。2. Description of the Related Art Some optical disks using a laser beam have already been put to practical use as large-capacity memories. However, with the increase in the amount of information, the development of an optical disk having a larger recording capacity is desired, and various methods for increasing the recording capacity have been developed. For example, since the recording capacity is inversely proportional to the laser beam diameter when recording and / or reproducing,
A method of reducing the beam diameter by using a short-wavelength laser or a high-NA objective lens has been proposed. High N
When the objective lens A is used, aberration due to deformation of the substrate increases. The problem is to reduce the thickness of the substrate, for example,
This can be avoided by setting it to about 0.6 mm. However, when the thickness of the substrate is reduced, the mechanical strength of the medium is reduced. Therefore, a medium in which two substrates are bonded together over the entire surface has been proposed. For example, as a recordable optical recording medium,
This is a bonding medium in which a substrate in which a recording layer and a reflective layer are laminated on a 0.6 mm substrate and a dummy substrate are bonded with the reflective layer inside.

【０００３】このような貼り合わせ媒体に於いては、そ
の貼り合わせに際して、記録・再生特性上や外観上から
接着層に気泡が残らないように接着しなければならな
い。接着方法は種々提案されており、その中でも、接着
剤を基板面にスクリーン印刷する方法は接着法が簡便で
あるため実用化されている。しかし、気泡が接着層に多
数残存する。接着層に残存する気泡は、記録層側に於い
ては反射層上に保護層を設けることによって記録・再生
特性には影響を与えなくなるが、外観上非常に見苦し
い。そこで、従来はこの外観上の問題を改善するため
に、ダミー基板側にも反射層を設け、光を遮断する方法
が実施されている。反射層は簡便に成膜することが出来
るが、薄膜であるため、通常該ダミー基板上の反射層を
保護するために反射層の上に保護層が設けられていた。
このように、従来法はダミー基板にも反射層と保護層を
必要とし、製造工程が煩雑になるという問題を有してい
た。[0003] In such a bonding medium, the bonding must be performed so that no air bubbles remain in the bonding layer from the viewpoint of recording / reproducing characteristics and appearance in bonding. Various bonding methods have been proposed. Among them, a method of screen-printing an adhesive on a substrate surface has been put to practical use because the bonding method is simple. However, many bubbles remain in the adhesive layer. On the recording layer side, the bubbles remaining in the adhesive layer do not affect the recording / reproducing characteristics by providing a protective layer on the reflective layer, but are very unsightly in appearance. Therefore, conventionally, in order to improve the appearance problem, a method of blocking the light by providing a reflective layer on the dummy substrate side has been implemented. The reflective layer can be easily formed, but since it is a thin film, a protective layer is usually provided on the reflective layer to protect the reflective layer on the dummy substrate.
As described above, the conventional method requires the reflection layer and the protective layer even on the dummy substrate, and has a problem that the manufacturing process is complicated.

【０００４】又、色素を含有する膜を記録層とする記録
可能媒体の場合は、媒体のダミー基板表面に、記録した
内容をペンで書いたり、プリンターで印刷したりする
が、この際、該印刷等は反射層を遮蔽して印刷した方が
見栄えが良く好ましい。そのために従来は、貼り合わせ
媒体のダミー基板側の表面の全面にわたりベタ印刷を行
い反射層を遮蔽していた。更に、通常用いられるダミー
基板表面は、例えば、水性のペンで書いたり、インクジ
ェットプリンターで印字するとインクをはじき、うまく
印字することが出来ず、該ダミー基板表面にインク受容
層を設ける必要があった。このように従来法では、ダミ
ー基板の一方の面に反射層や保護層を、更に他方の面に
ベタ印刷層とインク受容層を設けるいう非常に煩雑な工
程を必要とした。In the case of a recordable medium having a dye-containing film as a recording layer, the recorded contents are written on a dummy substrate surface of the medium with a pen or printed with a printer. For printing and the like, it is preferable that printing is performed with the reflective layer shielded, since the appearance is good. Therefore, conventionally, solid printing has been performed over the entire surface of the bonding medium on the dummy substrate side to shield the reflective layer. Furthermore, the surface of a dummy substrate that is usually used, for example, is repelled by ink when written with an aqueous pen or printed with an ink jet printer, and printing cannot be performed well, and it is necessary to provide an ink receiving layer on the surface of the dummy substrate. . As described above, the conventional method requires a very complicated process of providing a reflective layer and a protective layer on one surface of the dummy substrate and further providing a solid print layer and an ink receiving layer on the other surface.

【０００５】[0005]

【発明が解決しようとする課題】本発明の目的は、少な
くとも記録層と反射層を有する記録用基板とダミー用基
板を接着剤を介して貼り合わせてなる光記録媒体に於い
て、接着層に気泡が残存しても記録・再生特性に影響せ
ずに、且つ外観上該気泡が全く問題とはならず、更にダ
ミー基板表面に水性ペンやインクジェットプリンター等
で容易に印字することのできる貼り合わせ光記録媒体を
提供することである。SUMMARY OF THE INVENTION An object of the present invention is to provide an optical recording medium in which a recording substrate having at least a recording layer and a reflective layer and a dummy substrate are bonded together via an adhesive. Even if the bubbles remain, they do not affect the recording / reproducing characteristics, and the bubbles do not cause any problem in appearance, and can be easily printed on the dummy substrate surface with an aqueous pen or an ink jet printer. It is to provide an optical recording medium.

【０００６】[0006]

【課題を解決するための手段】本発明者らは、前記の光
記録媒体を簡単な工程で作ることのできる方法について
鋭意検討を行い、本発明を完成した。即ち、本発明は、
中心孔を有する円盤状の透明な基板に、少なくとも記
録層、反射層及び保護層を順次積層してなる記録用基板
と、前記基板と同じ様な基板の片面の略全面又は部分面
にベタ印刷を施したダミー用基板とを、前記記録用基板
の保護層面と前記ダミー用基板のベタ印刷面が対向する
ようにして、接着剤により貼り合わせてなることを特徴
とする光記録媒体、 前記の光記録媒体のダミー用基板の表面の全面又は
部分面にインク受容層を設けてなることを特徴とする光
記録媒体、 記録層が色素を含有する薄膜からなることを特徴とす
る前記又はの光記録媒体、 接着剤がカチオン重合型の紫外線硬化性樹脂である前
記の光記録媒体、 に関するものである。Means for Solving the Problems The present inventors have conducted intensive studies on a method for manufacturing the above-mentioned optical recording medium by simple steps, and completed the present invention. That is, the present invention
A recording substrate in which at least a recording layer, a reflective layer, and a protective layer are sequentially laminated on a disc-shaped transparent substrate having a center hole, and solid printing substantially on one entire surface or a partial surface of the same substrate as the substrate; An optical recording medium characterized by being bonded with an adhesive such that the protective layer surface of the recording substrate and the solid printing surface of the dummy substrate are opposed to each other. An optical recording medium comprising an ink receiving layer provided on the entire surface or a partial surface of the dummy substrate of the optical recording medium, wherein the recording layer comprises a thin film containing a dye; The recording medium, wherein the adhesive is a cationic polymerization type ultraviolet curable resin.

【０００７】[0007]

【発明の実施の形態】本発明に於いて用いられる中心孔
を有する円盤状の透明な基板とは、厚さが０．８〜０．
４ｍｍ、中心孔の直径が１５ｍｍ、外径が１３０〜８０
ｍｍ程度の透明な樹脂基板である。樹脂基板の具体例と
しては、ポリカーボネート樹脂、アクリル樹脂、ポリオ
レフィン系樹脂等からなる基板が挙げられる。そして、
この透明な樹脂基板の片面にはグルーブ及び又はプレピ
ットが形成され、その上に少なくとも記録層、反射層及
び保護層が順次積層されている。DESCRIPTION OF THE PREFERRED EMBODIMENTS A disk-shaped transparent substrate having a center hole used in the present invention has a thickness of 0.8 to 0.8 mm.
4mm, center hole diameter 15mm, outer diameter 130-80
It is a transparent resin substrate of about mm. Specific examples of the resin substrate include a substrate made of a polycarbonate resin, an acrylic resin, a polyolefin resin, or the like. And
Grooves and / or pre-pits are formed on one surface of the transparent resin substrate, and at least a recording layer, a reflective layer, and a protective layer are sequentially laminated thereon.

【０００８】本発明に於ける記録層としては、色素を含
有する薄膜、Ｔｅ等の金属からなる無機系化合物薄膜、
FeTbCoからなる光磁気記録合金薄膜、GeSbTe、AgInSbT
e、SnSbSe等の相変化記録合金薄膜等が挙げられる。こ
れらの記録層の中で製造の容易さや記録密度を大きくす
ることができる点からは、色素を含有する記録層が好ま
しい。色素の具体例としては、シアニン系色素、ポリメ
チン系色素、ポルフィリン系色素、フタロシアニン系色
素、アゾ系色素、金属錯体系色素、ナフトキノン系色素
等が挙げられる。また、色素を含有する記録層には、ポ
リマー、分解促進剤等を添加してもよい。色素を含有す
る記録層は、例えば、スピンコート法で成膜することが
できる。The recording layer in the present invention includes a thin film containing a dye, an inorganic compound thin film made of a metal such as Te,
Magneto-optical recording alloy thin film made of FeTbCo, GeSbTe, AgInSbT
e, phase change recording alloy thin films such as SnSbSe and the like. Among these recording layers, a recording layer containing a dye is preferable from the viewpoint that the production density and the recording density can be increased. Specific examples of the dye include a cyanine dye, a polymethine dye, a porphyrin dye, a phthalocyanine dye, an azo dye, a metal complex dye, and a naphthoquinone dye. Further, a polymer, a decomposition accelerator and the like may be added to the recording layer containing the dye. The recording layer containing a dye can be formed, for example, by a spin coating method.

【０００９】一方、記録層の上に設けられる反射層とし
ては、金、銀、白金、アルミ、銅、ニッケル等の金属又
はこれら金属を含む合金等が挙げられる。この反射層は
真空蒸着、スパッタ法などによって成膜することができ
る。又、本発明に於いては、接着層に残留する気泡の記
録・再生特性への影響を考慮して、前記反射層の上に、
保護層を成膜する。保護層は公知の紫外線硬化樹脂膜、
無機薄膜等が好ましい。さらに、本発明に於いては、基
板と記録層の間や、記録層と反射層の間に、誘電体層や
干渉層を設けても良い。On the other hand, examples of the reflective layer provided on the recording layer include metals such as gold, silver, platinum, aluminum, copper and nickel, and alloys containing these metals. This reflective layer can be formed by vacuum evaporation, sputtering, or the like. Further, in the present invention, in consideration of the effect of air bubbles remaining in the adhesive layer on the recording / reproducing characteristics, on the reflective layer,
A protective layer is formed. The protective layer is a known ultraviolet curable resin film,
An inorganic thin film is preferred. Further, in the present invention, a dielectric layer or an interference layer may be provided between the substrate and the recording layer or between the recording layer and the reflection layer.

【００１０】本発明に於いて用いられるダミー用基板と
は、前記記録用基板に用いられた基板の片面に光を遮蔽
するベタ印刷を行った基板である。より具体的には、前
記基板の全面又は部分的にベタ印刷を行う。印刷部分
は、貼り併せた際に、反射層が全面に渡って覆われるよ
うに、又は一部の反射層は覆われずに、ダミー基板側か
ら、例えば、円環状に見えるように印刷してあれば良
い。又、ベタ印刷の色は特に限定はなく、白、赤、黒、
黄、青、緑、金等や、それらの混合色が挙げられる。更
に、ダミー用基板にはベタ印刷を行う前にレーベル等の
文字や画像を印刷した後、ベタ印刷を行っても良い。The dummy substrate used in the present invention is a substrate on which one surface of the substrate used for the recording substrate has been subjected to solid printing for shielding light. More specifically, solid printing is performed on the entire surface or a part of the substrate. The printed portion is printed so that, when bonded, the reflective layer is covered over the entire surface, or some of the reflective layers are not covered, and from the dummy substrate side, for example, an annular shape is seen. I just want it. In addition, the color of solid printing is not particularly limited, white, red, black,
Yellow, blue, green, gold and the like, and a mixed color thereof can be mentioned. Furthermore, solid printing may be performed after characters or images such as labels are printed on the dummy substrate before solid printing is performed.

【００１１】本発明に於いては、前記記録用基板とベタ
印刷を施したダミー用基板を接着剤を用いて貼り合わせ
る。接着剤としては、加熱硬化型接着剤、紫外線硬化性
接着剤、ホットメルト接着剤、粘着性接着剤等が挙げら
れるが、作業性、生産性の点で紫外線硬化性接着剤が好
ましい。紫外線硬化性接着剤を用いて基板同士を貼り合
わせる際に、記録用基板かダミー用基板の少なくとも一
方が紫外線を透過する場合は、基板を接着剤を介して重
ね合わせた後、基板を通して紫外線を照射して硬化する
ことができる。In the present invention, the recording substrate and the solid printed dummy substrate are bonded to each other by using an adhesive. Examples of the adhesive include a heat-curable adhesive, an ultraviolet-curable adhesive, a hot-melt adhesive, a tacky adhesive, and the like, and an ultraviolet-curable adhesive is preferable in view of workability and productivity. When bonding together substrates using an ultraviolet curable adhesive, if at least one of the recording substrate and the dummy substrate transmits ultraviolet light, the ultraviolet light is passed through the substrate after the substrates are stacked via the adhesive. It can be cured by irradiation.

【００１２】本発明の媒体に於いては、記録用基板には
記録層と反射層が設けられており、他方、ダミー用基板
にはベタの印刷層が設けられている。反射層がハーフミ
ラーであったり、ベタ印刷層が紫外線を一部透過する場
合は前記したように基板同士を重ね合わせた後、基板を
通して紫外線を照射して貼り合わせることができるが、
本発明の媒体に於いては反射層やベタ印刷層が紫外線を
ほとんど透過しない場合が多いので、基板にスクリーン
印刷法やスピンコート法等で接着剤を塗布し、接着剤に
紫外線を照射した後、基板を重ね合わせて貼り合わす方
が好ましい。紫外線を照射した後、基板を重ね合わせ
て、貼り合わせる方法に於いては、用いられる接着剤と
しては、カチオン重合性の紫外線硬化成樹脂が硬化が遅
いので好ましい。In the medium of the present invention, the recording substrate is provided with a recording layer and a reflective layer, while the dummy substrate is provided with a solid printed layer. When the reflective layer is a half mirror, or when the solid print layer partially transmits ultraviolet light, after overlapping the substrates as described above, it can be bonded by irradiating ultraviolet light through the substrate,
In the medium of the present invention, since the reflection layer or the solid printing layer often hardly transmits ultraviolet light, an adhesive is applied to the substrate by a screen printing method, a spin coating method, or the like, and the adhesive is irradiated with ultraviolet light. It is more preferable that the substrates are overlapped and bonded. In the method of irradiating ultraviolet rays, superposing the substrates, and bonding the substrates, a cationically polymerizable ultraviolet curable resin is preferred as an adhesive to be used because curing is slow.

【００１３】本発明に於いては、貼り合わせた媒体のダ
ミー用基板側の表面にはインク受容層を設けた方が好ま
しい。インク受容層は媒体の記録内容を、例えば油性ペ
ン、水性ペン、インクジェットプリンター、熱転写プリ
ンター、昇華型プリンター等で印字したりする際に印字
し易くするためのものであり、印字方法によってそれぞ
れ公知のものが用いられる。インク受容層は媒体の略全
面に渡って設けてもよいし、部分的に設けてもよい。こ
の際に、レーベル等の文字や画像を印刷した後インク受
容層を設けてもよいし、インク受容層を設けた後にレー
ベル等の文字や画像を印刷してもよい。In the present invention, it is preferable to provide an ink receiving layer on the surface of the bonded medium on the dummy substrate side. The ink receiving layer is a recording content of the medium, for example, an oil-based pen, a water-based pen, an ink jet printer, a thermal transfer printer, to facilitate printing when printing with a sublimation printer, etc., each known by the printing method Things are used. The ink receiving layer may be provided over substantially the entire surface of the medium, or may be provided partially. At this time, an ink receiving layer may be provided after printing a character or image such as a label, or a character or image such as a label may be printed after providing the ink receiving layer.

【００１４】本発明に於いて作られた光記録媒体では、
その光を入射する面に、帯電防止や傷防止のために保護
層を設けることもできる。又、光ディスクの光入射面と
反対の面や基板の接着される面にレーベルの印刷などを
行うこともできる。In the optical recording medium made in the present invention,
A protective layer may be provided on the surface on which the light is incident to prevent electrification and damage. Label printing or the like can also be performed on the surface of the optical disk opposite to the light incident surface or on the surface to which the substrate is bonded.

【００１５】[0015]

【実施例】以下、実施例で本発明を具体的に示すが、本
発明はこれらに限定されるものではない。 実施例１ 通常の射出成型よって作られた片面にグルーブを有し、
直径１５ｍｍの中心孔を有する直径１２０ｍｍ、厚さ
０．６ｍｍのポリカーボネート樹脂基板のグルーブ面
に、シアニン色素（株式会社日本感光色素研究所製：MK
-4382 ）の４％テトラフロロプロパノール溶液をスピン
コート法により塗布し、記録層を形成した。この記録層
の上に、スパッタ法により８０ｎｍの金薄膜からなる反
射層を成膜し、更に反射層の上に紫外線硬化樹脂（ソニ
ーケミカル株式会社製：SKー5110 ）を塗布し、紫外線を
照射して保護層を成膜し、記録用基板を作った。一方、
上記した基板と同じ形状でグルーブを有さない基板の一
方の面に白色の紫外線硬化インクをスクリーン印刷法で
塗布し、紫外線を照射し、前記記録層を有する基板の反
射層が成膜されている部分に相当する部分に、白色のベ
タ印刷層を形成したダミー用基板を作った。次に、記録
用基板の保護層面及びダミー用基板の白色のベタ印刷面
に、それぞれスクリーン印刷法でカチオン重合型の紫外
線硬化型接着剤（ソニーケミカル株式会社製：SKー7000
）を、20μｍの厚みに塗布し、紫外線を照射した後、
直ちに二つの基板を重ね合わせて荷重を掛けて貼り合わ
せた。次いで、上記貼り合わせ基板のダミー用基板の表
面に、スクリーン印刷法でプリンタブルインク（日本化
薬株式会社製：KAYARAD KJP-855 ）を塗布してインク受
容層を形成した。このようにして作った媒体のインク受
容層面に、インクジェットプリンターを用いてフルカラ
ー印刷を行った。色の再現性に優れた印刷ができ、又、
接着層には気泡が残留していたにも拘わらず、外観上は
見えず、非常に良好な仕上がりであった。EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples. Example 1 Having a groove on one side made by ordinary injection molding,
On a groove surface of a polycarbonate resin substrate having a diameter of 120 mm and a thickness of 0.6 mm having a central hole having a diameter of 15 mm, a cyanine dye (MK: manufactured by Japan Photographic Dye Laboratories: MK)
-4382) was applied by a spin coating method to form a recording layer. On this recording layer, a reflective layer composed of an 80 nm gold thin film is formed by a sputtering method. Further, an ultraviolet curable resin (manufactured by Sony Chemical Corporation: SK-5110) is applied on the reflective layer, and irradiated with ultraviolet rays. Then, a protective layer was formed to form a recording substrate. on the other hand,
On one surface of the substrate having no groove in the same shape as the substrate described above, a white UV curable ink is applied by a screen printing method, irradiated with ultraviolet light, and a reflective layer of the substrate having the recording layer is formed. A dummy substrate in which a white solid printed layer was formed in a portion corresponding to the portion where the dummy substrate was formed. Next, on the protective layer surface of the recording substrate and the white solid printing surface of the dummy substrate, respectively, a cation polymerization type ultraviolet curing adhesive (manufactured by Sony Chemical Corporation: SK-7000) by a screen printing method.
) Is applied to a thickness of 20 μm and irradiated with ultraviolet rays.
Immediately, the two substrates were superimposed, a load was applied, and the substrates were bonded. Next, a printable ink (KAYARAD KJP-855, manufactured by Nippon Kayaku Co., Ltd.) was applied on the surface of the dummy substrate of the bonded substrate by a screen printing method to form an ink receiving layer. Full-color printing was performed on the surface of the ink receiving layer of the medium thus prepared using an inkjet printer. Printing with excellent color reproducibility is possible,
Despite the presence of air bubbles in the adhesive layer, the appearance was invisible and the finish was very good.

【００１６】比較例１ ダミー用基板に白色のベタ印刷を施さない以外は、実施
例１と同じ方法で貼り合わせを行い、媒体を作り、同じ
ようにインクジェットプリンターでフルカラー印刷を行
った。カラー印刷面からは接着層に残留する気泡が多数
観察され、且つ色調は金反射層からの反射の影響を受け
て全体に黄色みを帯びており、外観上の仕上がりは見難
かった。Comparative Example 1 Lamination was performed in the same manner as in Example 1 except that white solid printing was not performed on the dummy substrate, a medium was produced, and full-color printing was performed using an inkjet printer in the same manner. Many bubbles remaining in the adhesive layer were observed from the color printing surface, and the color tone was yellowish overall due to the influence of the reflection from the gold reflection layer, and the finished appearance was hard to see.

【００１７】実施例２ ダミー用基板に黒色でレーベル印刷を行った後、白色の
ベタ印刷を施したダミー用基板を用いた以外は、実施例
１と同じ方法で貼り合わせ媒体を作り、同じようにフル
カラー印刷を行った。黒のレーべル印刷の見てくれも良
好で、色の再現性に優れた印刷ができ、又、接着層には
気泡が残留していたにも拘わらず、外観上は見えず、非
常に良好な仕上がりであった。Example 2 A laminated medium was prepared in the same manner as in Example 1 except that a dummy substrate was printed in black on a dummy substrate, and then a white solid printed substrate was used. Was subjected to full color printing. The black label printing looks good and can be printed with excellent color reproducibility.Also, despite the bubbles remaining in the adhesive layer, the appearance is not visible and very good It was finished.

【００１８】[0018]

【発明の効果】記録層、反射層及び保護層を有する記録
用基板と、ダミー用基板とを、接着剤を介して貼り合わ
せてなる光記録媒体に於いて、ダミー用基板の接着面側
にベタ印刷を施しているために、接着層に残留する気泡
等による外観不良を隠蔽することができ、且つベタ印刷
が基板の厚さを介して眺められるために、仕上がり感に
優れ、更に光入射面の反対側にフルカラーの印刷をして
も記録用基板上の反射層がベタ印刷で遮蔽されるため
に、反射層の影響を受けず、色の再現性に優れ、非常に
きれいな印刷ができる。According to the present invention, in an optical recording medium in which a recording substrate having a recording layer, a reflective layer, and a protective layer and a dummy substrate are bonded via an adhesive, the recording substrate is provided on the bonding surface side of the dummy substrate. Since solid printing is applied, poor appearance due to bubbles and the like remaining in the adhesive layer can be concealed, and since solid printing can be viewed through the thickness of the substrate, the finished feeling is excellent, and further light incidence is achieved. Even if full color printing is performed on the opposite side of the surface, the reflective layer on the recording substrate is shielded by solid printing, so it is not affected by the reflective layer, excellent color reproducibility, and very clean printing is possible .

Claims (4)

【特許請求の範囲】[Claims] 【請求項１】 中心孔を有する円盤状の透明な基板に、
少なくとも記録層、反射層及び保護層を順次積層してな
る記録用基板と、前記基板と同じ様な基板の片面の略全
面又は部分面にベタ印刷を施したダミー用基板とを、前
記記録用基板の保護層面と前記ダミー用基板のベタ印刷
面が対向するようにして、接着剤により貼り合わせてな
ることを特徴とする光記録媒体。1. A disk-shaped transparent substrate having a center hole,
A recording substrate formed by sequentially laminating at least a recording layer, a reflective layer, and a protective layer, and a dummy substrate obtained by performing solid printing on substantially the entire surface or a partial surface of one side of the same substrate as the substrate, An optical recording medium characterized by being bonded with an adhesive such that a protective layer surface of a substrate and a solid printing surface of the dummy substrate face each other. 【請求項２】 請求項１の光記録媒体のダミー用基板の
表面の全面又は部分面にインク受容層を設けてなること
を特徴とする光記録媒体。2. The optical recording medium according to claim 1, wherein an ink receiving layer is provided on the entire surface or a partial surface of the dummy substrate of the optical recording medium. 【請求項３】 記録層が色素を含有する薄膜からなるこ
とを特徴とする請求項１又は２記載の光記録媒体。3. The optical recording medium according to claim 1, wherein the recording layer comprises a thin film containing a dye. 【請求項４】 接着剤がカチオン重合型の紫外線硬化性
樹脂である請求項３の光記録媒体。4. The optical recording medium according to claim 3, wherein the adhesive is a cationic polymerization type ultraviolet curable resin.