JPS59124896A - Optical recording medium - Google Patents
Optical recording mediumInfo
- Publication number
- JPS59124896A JPS59124896A JP57232242A JP23224282A JPS59124896A JP S59124896 A JPS59124896 A JP S59124896A JP 57232242 A JP57232242 A JP 57232242A JP 23224282 A JP23224282 A JP 23224282A JP S59124896 A JPS59124896 A JP S59124896A
- Authority
- JP
- Japan
- Prior art keywords
- optical recording
- recording medium
- ketone
- recording layer
- base
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Classifications
-
- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B7/00—Recording or reproducing by optical means, e.g. recording using a thermal beam of optical radiation by modifying optical properties or the physical structure, reproducing using an optical beam at lower power by sensing optical properties; Record carriers therefor
- G11B7/24—Record carriers characterised by shape, structure or physical properties, or by the selection of the material
- G11B7/241—Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the selection of the material
- G11B7/242—Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the selection of the material of recording layers
- G11B7/244—Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the selection of the material of recording layers comprising organic materials only
-
- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B7/00—Recording or reproducing by optical means, e.g. recording using a thermal beam of optical radiation by modifying optical properties or the physical structure, reproducing using an optical beam at lower power by sensing optical properties; Record carriers therefor
- G11B7/24—Record carriers characterised by shape, structure or physical properties, or by the selection of the material
- G11B7/241—Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the selection of the material
- G11B7/242—Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the selection of the material of recording layers
- G11B7/244—Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the selection of the material of recording layers comprising organic materials only
- G11B7/245—Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the selection of the material of recording layers comprising organic materials only containing a polymeric component
-
- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B7/00—Recording or reproducing by optical means, e.g. recording using a thermal beam of optical radiation by modifying optical properties or the physical structure, reproducing using an optical beam at lower power by sensing optical properties; Record carriers therefor
- G11B7/24—Record carriers characterised by shape, structure or physical properties, or by the selection of the material
- G11B7/241—Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the selection of the material
- G11B7/242—Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the selection of the material of recording layers
- G11B7/244—Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the selection of the material of recording layers comprising organic materials only
- G11B7/246—Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the selection of the material of recording layers comprising organic materials only containing dyes
-
- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B7/00—Recording or reproducing by optical means, e.g. recording using a thermal beam of optical radiation by modifying optical properties or the physical structure, reproducing using an optical beam at lower power by sensing optical properties; Record carriers therefor
- G11B7/24—Record carriers characterised by shape, structure or physical properties, or by the selection of the material
- G11B7/241—Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the selection of the material
- G11B7/242—Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the selection of the material of recording layers
- G11B7/244—Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the selection of the material of recording layers comprising organic materials only
- G11B7/246—Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the selection of the material of recording layers comprising organic materials only containing dyes
- G11B7/248—Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the selection of the material of recording layers comprising organic materials only containing dyes porphines; azaporphines, e.g. phthalocyanines
Landscapes
- Thermal Transfer Or Thermal Recording In General (AREA)
- Optical Record Carriers And Manufacture Thereof (AREA)
Abstract
Description
【発明の詳細な説明】
■ 発明の背景
技術分野
本発明は、光記録媒体、特にヒートモードの光記録媒体
に関する。DETAILED DESCRIPTION OF THE INVENTION (1) Background of the Invention Technical Field The present invention relates to an optical recording medium, particularly a heat mode optical recording medium.
先行技術
光記録媒体は、媒体と書き込みないし読み出しヘッドが
非接触であるので、記録媒体が摩耗劣化しないという特
徴をもち、このため、種々の光記録媒体の開発研究が行
われている。Prior art optical recording media have the characteristic that the recording medium does not deteriorate due to wear and tear because the medium and the writing or reading head are not in contact with each other, and for this reason, research and development of various optical recording media are being carried out.
このような光記録媒体のうち、暗室による画像処理が不
要である等の点で、ヒートモード光記録媒体の開発が活
発になっている。Among such optical recording media, heat mode optical recording media are being actively developed because they do not require image processing in a darkroom.
このヒートモードの光記録媒体は、記録光を熱として利
用する光記録媒体であり、その１例として、レーザー等
の記録光で媒体の一部を融解、除去等して、ビットと称
される小穴を形成して書き込みを行い、このビットによ
り情報を記録し、このビットを読み出し光で検出して読
み出しを行うものがある。This heat mode optical recording medium is an optical recording medium that uses recording light as heat. For example, a part of the medium is melted or removed using recording light such as a laser, and it is called a bit. Some write by forming small holes, recording information using these bits, and reading out by detecting these bits with read light.
そして、このようなピット形成型の媒体の１例として、
基体上に、熱可塑性ＶＭ脂と光吸収色素とからなる記録
層を塗設し、記録層を融解してピットを形成するものが
知られている。As an example of such pit-forming media,
It is known that a recording layer made of a thermoplastic VM resin and a light-absorbing dye is coated on a substrate, and the recording layer is melted to form pits.
そして、このような媒体は、熱または光によって、一旦
形成したピットを埋めもどして記録層表面を平坦化して
消去を行い、その後再ヒ゛曹き込みおよび読み出しを行
えることが確認されている。It has been confirmed that in such a medium, once formed pits can be filled back and the surface of the recording layer can be flattened for erasing using heat or light, and then re-recording and reading can be performed.
しかし、熱可塑性樹脂として、−Ｅ的に用いられている
ポ１ノスチレ／、ティ０／等を用いるときには、保存性
、特に耐熱性が低く、また、読み出しのＳ／Ｎ比も低く
、さらにくりかえしの消去によって、感度およびＳ／Ｎ
比が低下（消去劣化）してしまう。However, when using thermoplastic resins such as PO1NOSTIRE/ and T0/, which are used in By erasing the sensitivity and S/N
The ratio decreases (erase deterioration).
■ 発明の目的
本発明は、このような実状に鑑みなされたものであって
、゛その主たる目的は、熱可塑性樹脂と色素とからなる
記録層を有する光記録媒体において、その保存性を向上
し、消去劣化を減少させ、Ｓ／Ｎ比を向上させることに
ある。■ Purpose of the Invention The present invention was made in view of the above-mentioned circumstances, and its main purpose is to improve the storage stability of an optical recording medium having a recording layer made of a thermoplastic resin and a dye. The purpose of the present invention is to reduce erasure degradation and improve the S/N ratio.
このような目的は、以下の本発明によって達成される。Such objects are achieved by the following invention.
すなわち、本発明は、ケト／樹脂と色素とを含む記録層
を基体上に有することを％徴とする光記録媒体である。That is, the present invention is an optical recording medium having a recording layer containing a keto/resin and a dye on a substrate.
■ 発明の具体的構成 以下、本発明の具体的構成について詳細に説明する。■Specific structure of the invention Hereinafter, a specific configuration of the present invention will be explained in detail.
不発明の光記録媒体の記録層中には、色素が含廟される
。The recording layer of the optical recording medium according to the invention contains a dye.
用いる色素には、特に制限はなく、フクロシア二ノ系、
ナフタロシアニン系、コリンないしコロール系、アント
ラキノ／系、アゾ系、トリフェニルメタン系、ビリリウ
ムないしチアピリリウム塩系、アゾメチ／系、スチリル
系等の色素はいずれも使用可能である。There are no particular restrictions on the dyes used, including fucrocyanino,
Any of naphthalocyanine-based, choline- or chorol-based, anthraquino-based, azo-based, triphenylmethane-based, biryllium- or thiapyrylium salt-based, azomethy/based, styryl-based dyes can be used.
一方、記録層中に含有される熱可塑性の樹脂は、ケトン
樹脂である。On the other hand, the thermoplastic resin contained in the recording layer is a ketone resin.
用いるケトン樹脂としては、環状ケトン、特に脂環式ケ
トンをアルカリ金属で付加縮合したものであってもよい
。 また、ケトン、特に環状ケトンを、アルデヒド、
特にホルムアルデヒドと、アルカリで付加縮合したもの
であってもよい。The ketone resin used may be one obtained by addition-condensing a cyclic ketone, particularly an alicyclic ketone, with an alkali metal. Also, ketones, especially cyclic ketones, can be combined with aldehydes,
In particular, it may be addition-condensed with formaldehyde and an alkali.
このような中では、特に環状ケトンとホルムアルデヒド
との縮合物であることが好ましＸ、八〇
そして、環状ケトンとしては、シクロヘキサツノまたは
アセトフェノ／であることが好ましい。Among these, a condensate of a cyclic ketone and formaldehyde is particularly preferred.
一方、ケト／樹脂の数平均分子量は、１５００以下、特
に３００〜１２００であることが好ましい。On the other hand, the number average molecular weight of the keto/resin is preferably 1,500 or less, particularly 300 to 1,200.
これにより、耐熱性が向上し、消去劣化が減少する。This improves heat resistance and reduces erasure deterioration.
なお、好ましい態様において、ケトン樹脂が、シクロヘ
キサノンとホルムアルデヒドとの縮合物である場合、ヒ
ドロキシル価は２０〜６００、数平均分子量は３００〜
１０００であることが好ましい。In a preferred embodiment, when the ketone resin is a condensate of cyclohexanone and formaldehyde, the hydroxyl value is 20 to 600, and the number average molecular weight is 300 to 600.
Preferably it is 1000.
また、アセトフェノ／とホルムアルデヒドとの縮合物で
ある場合には、ヒドロキシル価は２０〜３００、数平均
分子量は３００〜１２０ （１であることが好ましい。Further, in the case of a condensate of acetophenol and formaldehyde, the hydroxyl value is 20 to 300 and the number average molecular weight is 300 to 120 (preferably 1).
このよ５なケトン樹脂は、公知の方法に従い合成するこ
とができ、特にシクロヘキサノン−ホルムアルデヒド樹
脂については、工業化学雑誌７２巻６号（１９６９）１
５４ページ、またアセトフェノ／−ホルムアルデヒド樹
脂については、工業化学雑誌７２巻６号（１９６９）１
６０ページ等に記載されている製造方法に従えばよい。Such five-dimensional ketone resins can be synthesized according to known methods, and in particular, cyclohexanone-formaldehyde resins are described in Industrial Chemistry Magazine, Vol. 72, No. 6 (1969), No. 1.
Page 54, and for acetopheno/-formaldehyde resin, see Industrial Chemistry Magazine Vol. 72, No. 6 (1969) 1.
The manufacturing method described on page 60 etc. may be followed.
なお、未反応の活性メチレンを不活性化すると好適であ
る。Note that it is preferable to inactivate unreacted active methylene.
また、ケト／樹脂には、種々の変性化を行ってもよい。The keto/resin may also be subjected to various modifications.
このような色素と、上記のケトン樹脂とは通常、重量比
で、１対０．１〜１０００童比にて設層される。Such a dye and the above-mentioned ketone resin are usually layered at a weight ratio of 1:0.1 to 1,000 to 1,000.
そして、記録層の厚さは、通常、０．０３〜］０μｍ程
度とされる。The thickness of the recording layer is usually about 0.03 to 0 μm.
また、このような記録層には、この他、他のポリマーな
いしオリゴマー、各種可塑剤、界面活性剤、帯電防止剤
、滑剤、難燃剤、安定剤、分散剤、架橋剤等が含有さ１
＋、ていても＼
よい。In addition, such a recording layer may contain other polymers or oligomers, various plasticizers, surfactants, antistatic agents, lubricants, flame retardants, stabilizers, dispersants, crosslinking agents, etc.
＋、Even if you stay＼ Good.
このような記録層を設層するには、基体上に、所定の溶
媒を用いて塗布、乾燥すれはよい。In order to form such a recording layer, it is sufficient to coat the substrate with a predetermined solvent and dry it.
このような記録層を設層する基体の材質には特に制限は
なく、各種樹脂、カラス、セラミックス、金属等いずれ
であってもよい。The material of the substrate on which such a recording layer is provided is not particularly limited, and may be any of various resins, glass, ceramics, metals, etc.
また、その形状は使用用途に応じ、テープ、ディスク、
ドラム、ベルト等いずれであってもよい。In addition, the shape varies depending on the purpose of use, such as tape, disk,
It may be a drum, a belt, etc.
ナオ、基体は、通常、トラッキング用の溝を有する。
また、必要に応じ、反射層等の下地層や蓄熱層や光吸収
層などを有するものであってもよい。The substrate usually has tracking grooves.
Further, if necessary, it may have a base layer such as a reflective layer, a heat storage layer, a light absorption layer, etc.
また、記録層上には、必要に応じ、透明基体を用いると
きに裏面として機能する反射層や、各種最十層保護層、
ハーフミラ一層などを設けることもできる。In addition, on the recording layer, if necessary, a reflective layer that functions as a back surface when using a transparent substrate, various protective layers, etc.
It is also possible to provide a single layer of half-mirror.
本発明の媒体は、このような基体の一面上に上記の記録
層を有するものであってもよく、その両面に記録層を有
するものであってもよい。 また、基体の一面上に記録
層を塗設したものを２つ用い、それらを記録Ｊ＆が向が
いあうようにして、所定の間隙をもって対向させ、それ
を密閉したりして、ホコリやギズがつかないようにする
こともできる。The medium of the present invention may have the recording layer described above on one surface of such a substrate, or may have recording layers on both surfaces thereof. In addition, two substrates with recording layers coated on one surface are used, and the recording layers are placed facing each other with a predetermined gap between them. You can also prevent it from sticking.
■ 発明の具体的作用
本発明の媒体は、走行ないし回転下において、記録光を
パルス状に照射する。 このとき、記録層中の色素の発
熱により、自己酸化性の樹脂が分解するか、あるいは熱
可塑性樹脂や、色素が融解し、ビットが形成される。(2) Specific Effects of the Invention The medium of the present invention is irradiated with recording light in pulses while running or rotating. At this time, due to the heat generated by the dye in the recording layer, the self-oxidizing resin decomposes or the thermoplastic resin or dye melts, forming bits.
このように形成されたビットは、やはり媒体の走行ない
し回転下、 読み出し光の反射光ないし透
過光、特に反射光を検出することにより読み出される。The bits formed in this manner are read out by detecting reflected or transmitted light of the readout light, especially reflected light, while the medium is running or rotating.
この場合、記録および読み出しは、基体側から行っても
、記録層側から行ってもよい。In this case, recording and reading may be performed from the base side or from the recording layer side.
そして、一旦記録層に形成したヒツトを光ないし熱で消
去し、再書き込みを行）こともできる。It is also possible to erase the hits once formed in the recording layer with light or heat and rewrite.
なお、記録ないし読み出し光としては、半導体レーザー
、Ｈｅ−Ｎｅ ｖ−ザー、ＡｒＬｚ−ザー、Ｈｅ−Ｃｄ
レーザー等を用いることが°できる。Note that recording or reading light may be a semiconductor laser, a He-Nev laser, an ArLz laser, or a He-Cd laser.
A laser or the like can be used.
■ 発明の具体的効果 本発明によれば、保存性、特に耐熱性が向上する。■Specific effects of the invention According to the present invention, storage stability, particularly heat resistance, is improved.
また、消去劣化も減少する。Also, erasure degradation is reduced.
さらに、読み出しのＳ／Ｎ比も向上する。Furthermore, the read S/N ratio is also improved.
そして、このような効果は、他の熱可塑性樹脂では実現
しない。Such an effect is not achieved with other thermoplastic resins.
本発明者らは、本発明の効果を確認するため種々実験を
行った。The present inventors conducted various experiments to confirm the effects of the present invention.
以下にその１例を示す。An example is shown below.
実施例
下記表１に示すケトン樹脂を、公知の方法に従い合成し
た。Examples Ketone resins shown in Table 1 below were synthesized according to known methods.
これら各ケトン樹脂を、銅フタロシアニン系の色素イ″
レオゾールファーストブルーＥＬ（住友化学社製）と溶
解しく溶媒メチルイソブチルケトノ）、これを１５ｃｒ
ｎφのアクリル基板上に、０．６μｍ厚にて設層した。These ketone resins are combined with copper phthalocyanine dyes.
Rheosol Fast Blue EL (manufactured by Sumitomo Chemical Co., Ltd.) and the solvent methyl isobutyl ketone), which was dissolved in 15 cr.
A layer with a thickness of 0.6 μm was formed on an nφ acrylic substrate.
これとは別に、比較のため、各ケトン樹脂を、数平均分
子量１１００のポリスチレン（ＰＳ）にかえ、同様に媒
体を作製した。Separately, for comparison, media were produced in the same manner except that each ketone resin was replaced with polystyrene (PS) having a number average molecular weight of 1100.
こメ′シも各媒体を６０Ｏｒｐｍで回転しなから、Ｈｅ
−Ｎｅレーザーを１μｍφに集光しく集光油出力１（
ｌｒｎνＶ）、３ Ｑ Ｑ ｎ ＳｅＣ巾のパルスとし
て所定周波数で照射して、書き込みを行った。This machine also rotates each medium at 60 rpm.
-To focus the Ne laser to 1 μmφ, the focusing oil output is 1 (
Writing was performed by irradiating at a predetermined frequency as a pulse with a width of 3 Q Q n SeC.
扱いで、上記のレーザーを１μｍφに集光しく集光油出
力１ｍν■）、読み出しを行い、読み出し光の反射光の
Ｃ／Ｎ比を測定した。The above laser was focused to 1 μmφ and the condensing oil output was 1 mν■), readout was performed, and the C/N ratio of the reflected light of the readout light was measured.
次いで、各媒体を５０℃、相対湿度８０％にて１００時
間保存したのちのＣ／Ｎ比を測定し、Ｃ／Ｎ比の劣化（
ｄＢ）を算出した。Next, each medium was stored at 50°C and 80% relative humidity for 100 hours, and then the C/N ratio was measured to determine the deterioration of the C/N ratio (
dB) was calculated.
また、赤外線う／ブを照射して、媒体を１２０℃、６０
秒間加熱して消去を行ったのち、再び曹き込みおよび読
み出しを行℃・、４３士３回消去後の貌み出しのＣ／Ｎ
比を測定し、Ｃ／Ｎ比の消去劣化（ｄＢ）を算出した。In addition, the medium was heated at 120°C and 60°C by irradiating it with infrared light.
After erasing by heating for a second, the C/N of the exposed surface after erasing three times is performed again at 43°C.
The ratio was measured, and the erasure degradation (dB) of the C/N ratio was calculated.
これらの結果を表２に示す。These results are shown in Table 2.
腐］ ４８ −２ −３扁２ ４９
−３ −２屑３ ４８ −２
−２Ａ４ ４９ −２ −３扁５
４９ −３ −２／１６６ ４８
２ ２ＰＳ ３７ −１９
−１８衣２に示される結果から、不発明σ）効果カ
ーあきらかである。rot] 48 -2 -3bian 2 49
-3 -2 scraps 3 48 -2
-2A4 49 -2 -3 flat 5
49 -3 -2/166 48
2 2PS 37 -19
From the results shown in -18-2, it is clear that the non-inventive σ) effect.
出願人 東京電気化学工業株式会社 代理人 弁理士 石 井 陽 −Applicant: Tokyo Denki Kagaku Kogyo Co., Ltd. Agent Patent Attorney Yo Ishii -
Claims (1)
ことを特徴とする光記録媒体。 ２、ケトン樹脂の数１ｉ均分子量が１５００以ドである
特許請求の範囲第１項に記載の光記録り某 休 。 ３ ケ（・ン樹脂が、環状ケトンの縮合物である特許
シ１−求の範囲第１項または第２項に記載の光記録媒体
。 ４ ケ）・ン樹脂か、環状ケトンとホルムアルデヒド
との縮合物である特許請求の範囲第３項に記・或の光記
録媒体。 ５ 環状ケトンかシクロヘキサノンである特１負＋Ｒ
１求の範囲第４項に記載の光記録媒体。 ６、 環状ケトンがアセトフェノンである特許請求の範
囲第４項に記載の光記録媒体。[Claims] 1. An optical recording medium characterized by having a recording layer containing a ketone resin and a dye on a substrate. 2. The optical recording medium according to claim 1, wherein the ketone resin has a number 1i average molecular weight of 1500 or less. 3. The optical recording medium according to item 1 or 2 of the patent application, wherein the resin is a condensation product of a cyclic ketone. 4. An optical recording medium according to claim 3, which is a condensate. 5 Cyclic ketone or cyclohexanone special 1 negative +R
1. The optical recording medium according to item 4. 6. The optical recording medium according to claim 4, wherein the cyclic ketone is acetophenone.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP57232242A JPS59124896A (en) | 1982-12-30 | 1982-12-30 | Optical recording medium |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP57232242A JPS59124896A (en) | 1982-12-30 | 1982-12-30 | Optical recording medium |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPS59124896A true JPS59124896A (en) | 1984-07-19 |
Family
ID=16936194
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP57232242A Pending JPS59124896A (en) | 1982-12-30 | 1982-12-30 | Optical recording medium |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS59124896A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS61177288A (en) * | 1985-02-04 | 1986-08-08 | ヘキスト・セラニーズ・コーポレーション | Optical information record medium containing organic large ring chromophore |
| JPS61186384A (en) * | 1985-02-13 | 1986-08-20 | Mitsubishi Chem Ind Ltd | Optically recording medium |
-
1982
- 1982-12-30 JP JP57232242A patent/JPS59124896A/en active Pending
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS61177288A (en) * | 1985-02-04 | 1986-08-08 | ヘキスト・セラニーズ・コーポレーション | Optical information record medium containing organic large ring chromophore |
| JPS61186384A (en) * | 1985-02-13 | 1986-08-20 | Mitsubishi Chem Ind Ltd | Optically recording medium |
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