JPH0337845A - Method for reproducing magnetic recording information - Google Patents
Method for reproducing magnetic recording informationInfo
- Publication number
- JPH0337845A JPH0337845A JP17227389A JP17227389A JPH0337845A JP H0337845 A JPH0337845 A JP H0337845A JP 17227389 A JP17227389 A JP 17227389A JP 17227389 A JP17227389 A JP 17227389A JP H0337845 A JPH0337845 A JP H0337845A
- Authority
- JP
- Japan
- Prior art keywords
- disk
- master
- magnetic
- information
- magneto
- 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
- 238000000034 method Methods 0.000 title claims description 25
- 239000000463 material Substances 0.000 claims abstract description 44
- 239000000696 magnetic material Substances 0.000 claims abstract description 16
- 239000011521 glass Substances 0.000 abstract description 6
- 238000010438 heat treatment Methods 0.000 abstract description 6
- 230000001681 protective effect Effects 0.000 abstract description 3
- 229910052736 halogen Inorganic materials 0.000 abstract description 2
- 150000002367 halogens Chemical class 0.000 abstract description 2
- 230000003287 optical effect Effects 0.000 abstract description 2
- 229910052681 coesite Inorganic materials 0.000 abstract 1
- 229910052906 cristobalite Inorganic materials 0.000 abstract 1
- 239000000377 silicon dioxide Substances 0.000 abstract 1
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N silicon dioxide Inorganic materials O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 abstract 1
- 229910052682 stishovite Inorganic materials 0.000 abstract 1
- 229910052905 tridymite Inorganic materials 0.000 abstract 1
- 239000010408 film Substances 0.000 description 17
- 230000005415 magnetization Effects 0.000 description 11
- 239000000203 mixture Substances 0.000 description 7
- 238000001816 cooling Methods 0.000 description 3
- 238000010586 diagram Methods 0.000 description 3
- 239000000853 adhesive Substances 0.000 description 2
- 230000001070 adhesive effect Effects 0.000 description 2
- 238000005299 abrasion Methods 0.000 description 1
- 239000011230 binding agent Substances 0.000 description 1
- 229910052799 carbon Inorganic materials 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000001678 irradiating effect Effects 0.000 description 1
- 238000003475 lamination Methods 0.000 description 1
- 239000006247 magnetic powder Substances 0.000 description 1
- 238000003825 pressing Methods 0.000 description 1
- 230000010076 replication Effects 0.000 description 1
- 239000002904 solvent Substances 0.000 description 1
- 239000010409 thin film Substances 0.000 description 1
- 238000010792 warming Methods 0.000 description 1
Classifications
-
- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B5/00—Recording by magnetisation or demagnetisation of a record carrier; Reproducing by magnetic means; Record carriers therefor
- G11B2005/0002—Special dispositions or recording techniques
- G11B2005/0005—Arrangements, methods or circuits
- G11B2005/0021—Thermally assisted recording using an auxiliary energy source for heating the recording layer locally to assist the magnetization reversal
-
- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B5/00—Recording by magnetisation or demagnetisation of a record carrier; Reproducing by magnetic means; Record carriers therefor
- G11B5/86—Re-recording, i.e. transcribing information from one magnetisable record carrier on to one or more similar or dissimilar record carriers
- G11B5/865—Re-recording, i.e. transcribing information from one magnetisable record carrier on to one or more similar or dissimilar record carriers by contact "printing"
Abstract
Description
【発明の詳細な説明】
［概要］
光磁気ディスク等の磁気情報の複製方法に関し、
６Ｂ気記録情報を短時間に復製する方法を提供すること
を目的とし、
磁気記録情報が書き込まれた原記録媒体に被複製材であ
る磁性体を近接もしくは密着させ、被複製材をそのキュ
リー温度近傍またはそれ以上の温度に加熱して原記録媒
体の磁気記録情報を写し取るように構成する。[Detailed Description of the Invention] [Summary] The purpose of this invention is to provide a method for duplicating magnetic information on magneto-optical disks and the like, and to provide a method for reproducing 6B recorded information in a short time. A magnetic material, which is a material to be copied, is brought close to or in close contact with the medium, and the material to be copied is heated to a temperature close to or higher than its Curie temperature, thereby copying magnetically recorded information on the original recording medium.
〔産業上の利用分野］
本発明は光磁気ディスク等の磁気情報の復製方法に関す
る。[Industrial Field of Application] The present invention relates to a method for reproducing magnetic information on a magneto-optical disk or the like.
［従来の技術］
従来は磁気情報の適当な複製方法がなかったために、光
ディスクなどの記録媒体の一枚一枚について情報を磁気
的または光学的に記録する必要があった。[Prior Art] Conventionally, since there was no suitable method for copying magnetic information, it was necessary to magnetically or optically record information on each recording medium such as an optical disk.
なお、凹凸情報を記録媒体から別の記録媒体に複製する
ためには可塑性材料を圧着し、剥がしとる方法などがあ
るが、この方法では磁気情報の複製はできない。Note that in order to copy unevenness information from one recording medium to another, there is a method of pressing a plastic material and peeling it off, but magnetic information cannot be copied with this method.
［発明が解決しようとする課題］
従来のように、−枚、−枚情報を記録する方法では、記
録情報が多い場合に時間がかかり能率的ではない。[Problems to be Solved by the Invention] The conventional method of recording -sheet, -sheet information takes time and is not efficient when there is a large amount of recorded information.
したがって、磁気記録情報を短時間に複製する方法を提
供することが本発明の目的である。Accordingly, it is an object of the present invention to provide a method for duplicating magnetically recorded information in a short period of time.
本課題は、磁性体をキュリー温度付近まで加熱するとそ
の磁化の向きが外部の磁界の方向に容易に向くことを利
用することで達成される。This problem can be achieved by utilizing the fact that when a magnetic material is heated to around its Curie temperature, its magnetization direction is easily directed in the direction of an external magnetic field.
すなわち、外部磁界として、あらかじめ磁気情報が記録
しである原盤を用い、これに被記録材を近接らしくは密
着させ、被記録材をキュリー温度付近まで加熱すれば、
原盤が垂直は気記録媒体のように磁気的に配向している
場合は被記録材の磁化の向きは冷却中に原盤の記録情報
の向きと同じになり、一方、原盤が水平磁気記録媒体の
ように磁気的配向はランダムであるが着磁の方向性によ
り情報が記録されている場合は被記録材の着磁の方向が
冷却中に原盤の着磁の方向と同じになるので、原盤の情
報を一度に被記録材上に複製することができる。That is, if you use a master disk on which magnetic information has been previously recorded as an external magnetic field, place a recording material in close contact with it, and heat the recording material to around the Curie temperature,
If the master is magnetically oriented vertically, such as in a horizontal magnetic recording medium, the direction of magnetization of the recording material becomes the same as the direction of the recorded information on the master during cooling; Although the magnetic orientation is random, if information is recorded by the directionality of magnetization, the direction of magnetization of the recording material becomes the same as the direction of magnetization of the master disk during cooling, so the direction of magnetization of the master disk is Information can be copied onto the recording material at one time.
すなわち、本発明は、磁気記録情報が書き込まれた原記
録媒体に被複製材である磁性体を近接もしくは密着させ
、被複製材をそのキュリー温度近傍もしくはそれ以上の
温度に加熱して原記録媒体の磁気記録情報を写し取るこ
とを特徴とする複製方法である。That is, the present invention brings a magnetic material, which is a material to be copied, close to or in close contact with an original recording medium on which magnetically recorded information has been written, and heats the material to be copied to a temperature close to or higher than its Curie temperature. This is a reproduction method characterized by copying magnetically recorded information.
以下、原記録媒体が円盤状である例につき説明を行なう
が、媒体の形状はこれに限定されない。 本発明の方法
を行うにあたっては、加熱によって原盤の情報を消さな
いことが重要である。An example in which the original recording medium is disk-shaped will be described below, but the shape of the medium is not limited to this. When carrying out the method of the present invention, it is important not to erase information on the master disc by heating.
このためには、
■原盤となる磁性体のキュリー温度を被複製材となる磁
性体のそれより高く設定しておく、■原盤となる磁性体
と被複製材となる磁性体との間に熱伝導の悪い膜を介在
させる
■被複製材に良く吸収される電磁波を照射して、被複製
材だけを加熱する
■原盤となる磁性体の熱容量を被複製材となる磁性体の
熱容量よりも大きく設定するなどといった手段が考えら
れる。To do this, ■ Set the Curie temperature of the magnetic material that will be the master to be higher than that of the magnetic material that will be the copied material, and ■ Heat the temperature between the magnetic material that will be the master and the magnetic material that will be the copied material. Interpose a film with poor conductivity ■ Heat only the material to be copied by irradiating electromagnetic waves that are well absorbed by the material to be copied ■ Make the heat capacity of the magnetic material that is the master greater than the heat capacity of the magnetic material that will be the material to be copied Possible methods include setting.
ただし原盤のＩａ磁気情報消さずに被複製材の温度を上
げることができる方法ならば上記手段に限らず適用する
ことができる。However, any method that can raise the temperature of the material to be copied without erasing the Ia magnetic information on the master is applicable without being limited to the above method.
■の具体的としてはプラスチック、５ｉＯ−などの低熱
伝導性かつ非磁性の膜を用いる方法がある。■はフラッ
シュランプによる加熱などで行なう。■は原盤の磁性体
を厚くすることなどにより行なう。A specific example of method (2) is to use a film of low thermal conductivity and non-magnetic properties such as plastic or 5iO-. (3) is performed by heating with a flash lamp. (2) is achieved by making the magnetic material of the master thicker.
加熱温度が低過ぎると転写ができず、高すぎると原盤が
キュリー温度以上に加熱されるおそれが大になる。なお
、被複製材をキュリー温度以上に加熱して冷却中に複製
を行なってもよいが、原盤も高温加熱されるので、その
情報を消さないように上記■〜■の手段を注意深く行な
う必要がある。また、原盤と被複製材の間隔は広すぎる
と、外部磁場が小さくなり、狭すぎると原盤が高（品に
加熱されるという利害得失がある。しかしながら、原盤
となる磁性体が被複製材である磁性体よりも高キュリー
点、高残留磁化を有する場合は、両者が密着した状態で
後者を加熱してもよい。密着させる具体的方法は、予め
製膜した彼’ｔＷ ？Ｊ材を機械的に原盤に押し付ける
方法、被製膜材を真空製膜法で原盤上に形成するかある
いは磁性粉を溶剤・バインダとと６に原盤上にスピンコ
ードする方法を採用する。If the heating temperature is too low, transfer will not be possible, and if the heating temperature is too high, there is a high risk that the master will be heated to a temperature higher than the Curie temperature. Note that it is also possible to heat the material to be copied above the Curie temperature and perform the copying while it is cooling, but since the master is also heated to a high temperature, it is necessary to carefully perform the steps ① to ② above so as not to erase the information. be. In addition, if the distance between the master and the material to be copied is too wide, the external magnetic field will be small, and if it is too narrow, the master will be heated. If the latter has a higher Curie point and higher residual magnetization than a certain magnetic material, the latter may be heated while the two are in close contact with each other. A method is adopted in which the material to be coated is formed on the master disc by a vacuum film forming method, or a method is adopted in which magnetic powder is coated with a solvent and a binder and spin-coded onto the master disc.
一般の光磁気ディスクには光磁気記録情報の他に凹凸情
報が記録されていることがある。この場合は、原盤の複
製のためにはこれら２種類の情報を原盤から被複製材に
転写する必要があるので、真空製膜法あるいはスピンコ
ード法によって凹凸を膜に再現する。これらの方法によ
り原盤に製膜された皮膜は、必要により、接着性の材料
で支持板上に被複写材を固定し、その後原盤より剥離す
る。In addition to magneto-optical recording information, concavo-convex information may be recorded on a general magneto-optical disk. In this case, since it is necessary to transfer these two types of information from the master to the material to be copied in order to reproduce the master, the irregularities are reproduced on the film by a vacuum film forming method or a spin code method. The film formed on the master by these methods fixes the material to be copied on the support plate with an adhesive material, if necessary, and then peels it off from the master.
被複製材はこのままでは薄膜状態なので、これに接着剤
等と支持材を重ね合わせて原盤から剥がし取れば、原盤
も何度で６使用できる。Since the material to be copied is in a thin film state as it is, if an adhesive or a support material is layered on it and then peeled off from the master, the master can be used over and over again.
被複製材は原盤の磁性体と同一組成でもよく、同一成分
系で保磁力が原盤より低い組成でもよく、別成分系でも
よい。被複製材の厚みは複製媒体の強度、摩耗などを考
慮して適宜窓められる。 また原盤の残留暖化は、−ｌ
“、−〇″より構成される情報のコントラストに影響を
与え、残留磁化が大きいほど複製が忠実に行われ、ｌ″
とＯ“のコンストラストが良好な複製板が得られる。The material to be copied may have the same composition as the magnetic material of the master, may have the same composition but have a lower coercive force than the master, or may have a different composition. The thickness of the material to be copied is determined as appropriate, taking into consideration the strength, abrasion, etc. of the copying medium. Also, the residual warming of the master is -l
It affects the contrast of information composed of ", -〇", and the larger the residual magnetization, the more faithful the replication,
A reproduction board with good contrast between the two directions can be obtained.
［作用］
本発明によれば、被複製材を加熱することにより多量の
磁気記録情報を短時間で複製することができる。[Operation] According to the present invention, a large amount of magnetically recorded information can be copied in a short time by heating the material to be copied.
［実施例］ 以下、実施例によりさらに詳しく本発明を説明する。[Example] Hereinafter, the present invention will be explained in more detail with reference to Examples.
実施例１
原盤として、あらかじめ磁気情報を記録した貼合わせる
前の光磁気ディスクを用いた原盤用ディスクの構成を第
２図に示す。図中、１は直径１３０ｍｍ、内径１５＋ｎ
ｍ、厚み１．２ｍ＋ｎのガラス円板、２．２″は厚みが
１１００ｎのＴｂ−５ｉｎ。Example 1 FIG. 2 shows the configuration of a master disk using a magneto-optical disk on which magnetic information has been recorded in advance before lamination as a master disk. In the figure, 1 has a diameter of 130 mm and an inner diameter of 15+n.
m, a glass disk with a thickness of 1.2m+n, and 2.2″ is a Tb-5in with a thickness of 1100n.
保護膜、３は厚みが１１００ｎのＴｂＦｅＣｏ光磁気記
録用磁性膜である。磁性Ｉｔ！３の組成は２２ａｔ％Ｔ
ｂ、７０ａｔ％Ｆｅ、 ８ａｔ％Ｃｏ、キュリー温度（
Ｔｃ）は２００℃、残留磁化（Ｍｒ）は１． ＯＯｅｍ
ｕ／ｃｃである。The protective film 3 is a TbFeCo magneto-optical recording magnetic film having a thickness of 1100 nm. Magnetic It! The composition of 3 is 22at%T
b, 70at%Fe, 8at%Co, Curie temperature (
Tc) is 200°C, residual magnetization (Mr) is 1. OOem
It is u/cc.
上記原盤用ディスク１０の上に、原盤用ディスクと同じ
構成の光磁気ディスク２０（第１図）を被複製材として
、磁性膜が向き合うように重ね合わせた。A magneto-optical disk 20 (FIG. 1) having the same structure as the master disk was superimposed on the master disk 10 as a copying material so that the magnetic films faced each other.
被複製材の磁性膜の組成は原盤用ディスクの組成と同じ
である。The composition of the magnetic film of the material to be copied is the same as that of the master disk.
第１図において、４は第２図の各Ｍ２．２′３．５はガ
ラス円板、６は２．２′、３のように積層した磁性膜と
保護膜を示す。In FIG. 1, reference numeral 4 indicates a glass disk, M2.2', 3.5 in FIG. 2, 6 indicates a magnetic film and a protective film laminated as shown in 2.2', 3.
被複製材としての光磁気ディスク２０側から、ガラス円
板５を通してハロゲンランプ８を数百マイクロ秒間照射
（３０００Ｊ／全面）して被複製材である光磁気ディス
ク２０の磁性体を加熱した。両者】０．２０をはなして
、被複製材である光磁気ディスク２０に複製した情報を
磁気光学的に再生したところ、原盤１０の情報と全く同
じ情報−が得られた。A halogen lamp 8 was irradiated for several hundred microseconds (3000 J/entire surface) from the side of the magneto-optical disk 20 as a material to be copied through the glass disk 5 to heat the magnetic material of the magneto-optical disk 20 as a material to be copied. When the information duplicated on the magneto-optical disk 20, which is the material to be copied, was reproduced magneto-optically with a difference of 0.20, exactly the same information as the information on the master disk 10 was obtained.
実施例２ 原盤として、第１図に示した膜組成よりＣ。Example 2 As the master, C from the film composition shown in Figure 1.
量を増やしてキュリー温度、残留磁化の値を大きくし、
あらかじめ磁気情報を記録した光磁気ディスクを用いた
（ただし貼合わせる前のもの）。By increasing the amount, the Curie temperature and residual magnetization values are increased.
A magneto-optical disk on which magnetic information was recorded in advance was used (but before it was pasted).
原盤用ディスクの構成は第２図に示すとおりであり、原
盤用ディスクの磁性膜の組成は１８ａｔ％Ｔｂ、５７ａ
ｔ％Ｆｅ、２５ａｔ％ＣＯ、キュリー温度は３００℃、
残留磁化（Ｍｒ）は１５０ｅｍｕ／ｃｃである。上記原
盤用ディスクの上に、実施例１に示した構成の光磁気デ
ィスクを被複製材として、磁性膜が向き合うように重ね
合わせた（第３図）。The configuration of the master disk is as shown in Figure 2, and the composition of the magnetic film of the master disk is 18at%Tb, 57a.
t%Fe, 25at%CO, Curie temperature 300°C,
The residual magnetization (Mr) is 150 emu/cc. A magneto-optical disk having the configuration shown in Example 1 was used as a copying material and superimposed on the master disk so that the magnetic films faced each other (FIG. 3).
２枚のディスク１０．２０を２００°Ｃの恒温１曹９に
入れ、３分間加熱した。両者をはなして、被複製材であ
る光磁気ディスク２０に？Ｍ製した情報を磁気光学的に
再生したところ、原盤の情報と全く同じ情報が得られた
。The two discs 10.20 were placed in a constant temperature 1-carbon 9 at 200°C and heated for 3 minutes. Separate them and transfer them to the magneto-optical disk 20, which is the material to be copied? When the information produced by M was reproduced magneto-optically, exactly the same information as the original was obtained.
［発明の効果］
以上のように、本発明によれば磁気記録情報を短時間に
複製できるので、同一情報を大量にかつ安価に複製する
ことができる。[Effects of the Invention] As described above, according to the present invention, magnetically recorded information can be duplicated in a short time, so that a large amount of the same information can be duplicated at low cost.
第１図は、実施例１の方法を説明する図、第２図は原盤
および複製用ディスクの説明図、
第３図は実施例２の方法を説明する図である。
１−ガラス円板、２−保護膜、３−光磁気記録用磁性膜
、１０−原盤、２０−被複製材光磁気ディスクFIG. 1 is a diagram illustrating the method of the first embodiment, FIG. 2 is a diagram illustrating a master and a copying disk, and FIG. 3 is a diagram illustrating the method of the second embodiment. 1-Glass disk, 2-protective film, 3-magnetic film for magneto-optical recording, 10-master, 20-copied material magneto-optical disk
Claims (1)
である磁性体を近接もしくは密着させ、被複製材をその
キュリー温度近傍またはそれ以上の温度に加熱して原記
録媒体の磁気記録情報を写し取ることを特徴とする複製
方法。 ２、被複製材を真空製膜法で原盤上に形成し、製膜後こ
れを原盤から剥離することによって、原盤の凹凸情報と
ともに磁気情報を複製することを特徴とする請求項１記
載の複製方法。[Claims] 1. A magnetic material, which is a material to be copied, is brought close to or in close contact with the original recording medium on which magnetically recorded information has been written, and the material to be copied is heated to a temperature close to or higher than its Curie temperature. A reproduction method characterized by copying magnetically recorded information on a recording medium. 2. The reproduction according to claim 1, characterized in that the material to be copied is formed on the master by a vacuum film forming method, and after the film is formed, the material is peeled from the master to reproduce the magnetic information along with the unevenness information of the master. Method.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP17227389A JPH0337845A (en) | 1989-07-04 | 1989-07-04 | Method for reproducing magnetic recording information |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP17227389A JPH0337845A (en) | 1989-07-04 | 1989-07-04 | Method for reproducing magnetic recording information |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH0337845A true JPH0337845A (en) | 1991-02-19 |
Family
ID=15938857
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP17227389A Pending JPH0337845A (en) | 1989-07-04 | 1989-07-04 | Method for reproducing magnetic recording information |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0337845A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP1122718A2 (en) * | 2000-02-03 | 2001-08-08 | Mitsubishi Chemical Corporation | Method for forming a magnetic pattern in a magnetic recording medium, method for producing a magnetic recording medium, magnetic pattern forming device, magnetic recording medium and magnetic recording device |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS57105827A (en) * | 1980-12-23 | 1982-07-01 | Olympus Optical Co Ltd | Manufacture of recorded medium |
| JPS619850A (en) * | 1984-06-23 | 1986-01-17 | Oki Electric Ind Co Ltd | Guide track forming method of photomagnetic recording medium |
-
1989
- 1989-07-04 JP JP17227389A patent/JPH0337845A/en active Pending
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS57105827A (en) * | 1980-12-23 | 1982-07-01 | Olympus Optical Co Ltd | Manufacture of recorded medium |
| JPS619850A (en) * | 1984-06-23 | 1986-01-17 | Oki Electric Ind Co Ltd | Guide track forming method of photomagnetic recording medium |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP1122718A2 (en) * | 2000-02-03 | 2001-08-08 | Mitsubishi Chemical Corporation | Method for forming a magnetic pattern in a magnetic recording medium, method for producing a magnetic recording medium, magnetic pattern forming device, magnetic recording medium and magnetic recording device |
| EP1122718A3 (en) * | 2000-02-03 | 2003-10-15 | Mitsubishi Chemical Corporation | Method for forming a magnetic pattern in a magnetic recording medium, method for producing a magnetic recording medium, magnetic pattern forming device, magnetic recording medium and magnetic recording device |
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