JPS6156563B2 - - Google Patents
Info
- Publication number
- JPS6156563B2 JPS6156563B2 JP55163885A JP16388580A JPS6156563B2 JP S6156563 B2 JPS6156563 B2 JP S6156563B2 JP 55163885 A JP55163885 A JP 55163885A JP 16388580 A JP16388580 A JP 16388580A JP S6156563 B2 JPS6156563 B2 JP S6156563B2
- Authority
- JP
- Japan
- Prior art keywords
- oxygen
- magnetic
- magnetic layer
- coercive force
- substrate
- 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.)
- Expired
Links
- 239000001301 oxygen Substances 0.000 claims description 30
- 229910052760 oxygen Inorganic materials 0.000 claims description 30
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims description 28
- 239000000758 substrate Substances 0.000 claims description 14
- 230000008020 evaporation Effects 0.000 claims description 11
- 238000001704 evaporation Methods 0.000 claims description 11
- 239000000696 magnetic material Substances 0.000 claims description 9
- 238000004519 manufacturing process Methods 0.000 claims description 9
- 229920000307 polymer substrate Polymers 0.000 claims description 5
- 238000000034 method Methods 0.000 description 7
- 238000000151 deposition Methods 0.000 description 5
- 239000010409 thin film Substances 0.000 description 5
- 238000007740 vapor deposition Methods 0.000 description 5
- 230000008021 deposition Effects 0.000 description 4
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 2
- UQSXHKLRYXJYBZ-UHFFFAOYSA-N Iron oxide Chemical compound [Fe]=O UQSXHKLRYXJYBZ-UHFFFAOYSA-N 0.000 description 2
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 description 2
- 239000011230 binding agent Substances 0.000 description 2
- 239000010941 cobalt Substances 0.000 description 2
- 229910017052 cobalt Inorganic materials 0.000 description 2
- GUTLYIVDDKVIGB-UHFFFAOYSA-N cobalt atom Chemical compound [Co] GUTLYIVDDKVIGB-UHFFFAOYSA-N 0.000 description 2
- 230000007423 decrease Effects 0.000 description 2
- 238000010894 electron beam technology Methods 0.000 description 2
- 239000010408 film Substances 0.000 description 2
- 238000010438 heat treatment Methods 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 150000002926 oxygen Chemical class 0.000 description 2
- 239000000843 powder Substances 0.000 description 2
- MBMLMWLHJBBADN-UHFFFAOYSA-N Ferrous sulfide Chemical compound [Fe]=S MBMLMWLHJBBADN-UHFFFAOYSA-N 0.000 description 1
- 239000000956 alloy Substances 0.000 description 1
- 229910045601 alloy Inorganic materials 0.000 description 1
- 229940090961 chromium dioxide Drugs 0.000 description 1
- IAQWMWUKBQPOIY-UHFFFAOYSA-N chromium(4+);oxygen(2-) Chemical compound [O-2].[O-2].[Cr+4] IAQWMWUKBQPOIY-UHFFFAOYSA-N 0.000 description 1
- AYTAKQFHWFYBMA-UHFFFAOYSA-N chromium(IV) oxide Inorganic materials O=[Cr]=O AYTAKQFHWFYBMA-UHFFFAOYSA-N 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- WMVRXDZNYVJBAH-UHFFFAOYSA-N dioxoiron Chemical compound O=[Fe]=O WMVRXDZNYVJBAH-UHFFFAOYSA-N 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000007789 gas Substances 0.000 description 1
- 230000006698 induction Effects 0.000 description 1
- 229910052742 iron Inorganic materials 0.000 description 1
- 238000010030 laminating Methods 0.000 description 1
- 229910052759 nickel Inorganic materials 0.000 description 1
- 230000001590 oxidative effect Effects 0.000 description 1
- 238000007747 plating Methods 0.000 description 1
- -1 polyethylene terephthalate Polymers 0.000 description 1
- 229920000139 polyethylene terephthalate Polymers 0.000 description 1
- 239000005020 polyethylene terephthalate Substances 0.000 description 1
- 230000002265 prevention Effects 0.000 description 1
- 238000004544 sputter deposition Methods 0.000 description 1
- 238000004804 winding 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
- G11B5/84—Processes or apparatus specially adapted for manufacturing record carriers
- G11B5/851—Coating a support with a magnetic layer by sputtering
Landscapes
- Physical Vapour Deposition (AREA)
- Manufacturing Of Magnetic Record Carriers (AREA)
- Thin Magnetic Films (AREA)
Description
【発明の詳細な説明】
本発明は、磁気記録媒体の製造方法に係り、薄
膜磁性層で高保磁力の磁気記録媒体の製造方法を
提供するものである。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method of manufacturing a magnetic recording medium, and provides a method of manufacturing a magnetic recording medium with a thin film magnetic layer and a high coercive force.
すなわち、本発明は幅100mm、長さ100m以上の
高分子基板を10-3Torr以下の真空槽内で、連続
的に走行させた状態で、磁性材料である鉄、コバ
ルト、ニツケル等の単一あるいは複数の磁性材を
連続的に蒸発させ、基板表面上に薄膜磁性層を得
るものである。ここで磁性層の積層時に、基板お
よび磁性材蒸発近傍に酸化性ガスである酸素を本
発明に示す方法で供給することにより高保磁力を
もつ磁気記録媒体の製造方法を実現したものであ
る。 That is, the present invention involves a polymer substrate having a width of 100 mm or more and a length of 100 m or more being continuously run in a vacuum chamber of 10 -3 Torr or less, and a single magnetic material such as iron, cobalt, nickel, etc. Alternatively, a plurality of magnetic materials are continuously evaporated to form a thin magnetic layer on the surface of the substrate. Here, a method of manufacturing a magnetic recording medium with high coercive force was realized by supplying oxygen, which is an oxidizing gas, to the substrate and the vicinity of the evaporation of the magnetic material by the method shown in the present invention when laminating the magnetic layers.
一般に、現在使用されているテープレコーダ
ー、ビデオテープレコーダー、電子計算機等の記
録媒体としては、酸化鉄（FeO2）や二酸化クロム
（CrO2）等の磁性材料を微小な粉末とした後、適
当なバインダーと共に基板上に塗布固定したもの
が主流であり、塗布型テープと呼ばれている。塗
布型テープにおいて、保磁力を得るために種々の
工夫がなさされており、一例として硫化第一鉄
（FeSO47H2O）を適当な各種処理工程により0.2
〜1.0μｍの針状酸化鉄にして使用し保磁力を得
ているが、高密度記録化において保磁力はまだ不
十分である。また塗布型の磁気記録媒体にあつて
は、バインダーを介して磁性体を固定し、基板と
に磁性層を形成するため磁性層に占める磁性体の
密度が低く、磁性層厚も数μｍ程度の厚みにな
る。磁性層厚は与えられた長さのテープに蓄えら
れる情報ビツトの数が厚さが薄いほど増加する。
テープ状のビツト間の最小間隔は、おおよそ、そ
の厚さに正比例するといわれている。したがつて
塗布型テープで高密度記録を実現しようとすると
きは、保持力、磁性体密度、磁性層厚等により
種々の問題が生じてくる。 In general, recording media for tape recorders, video tape recorders, electronic computers, etc. currently in use are made by grinding magnetic materials such as iron oxide (FeO 2 ) or chromium dioxide (CrO 2 ) into fine powder, and then using an appropriate powder. The mainstream is one that is coated and fixed on a substrate together with a binder, and is called a coated tape. Various efforts have been made to obtain a coercive force in coated tapes. For example, ferrous sulfide (FeSO 4 7H 2 O) is reduced to 0.2
Coercive force has been obtained by using acicular iron oxide of ~1.0 μm, but the coercive force is still insufficient for high-density recording. In addition, in the case of coated magnetic recording media, the magnetic material is fixed via a binder and a magnetic layer is formed on the substrate, so the density of the magnetic material in the magnetic layer is low, and the magnetic layer thickness is approximately several micrometers. It becomes thick. The magnetic layer thickness increases as the number of information bits that can be stored on a given length of tape decreases.
The minimum spacing between bits in a tape is said to be approximately directly proportional to its thickness. Therefore, when attempting to realize high-density recording with a coated tape, various problems arise due to coercive force, magnetic density, magnetic layer thickness, etc.
一方、蒸着法やスパツター法、メツキ法等によ
ると、磁性層はほぼ100％磁性体で構成され、し
かも磁性層が極めて薄い薄膜磁性層を形成できる
ことが知られている。 On the other hand, it is known that by vapor deposition, sputtering, plating, or the like, it is possible to form a thin magnetic layer that is composed of almost 100% magnetic material and has an extremely thin magnetic layer.
本発明は、前述した高密度記録化への問題点を
解決する、薄膜磁性層を持つ磁気記録媒体を提供
するものである。 The present invention provides a magnetic recording medium having a thin film magnetic layer that solves the above-mentioned problems in achieving high-density recording.
以下実施例をあげて詳細な説明を行う。 A detailed explanation will be given below with reference to examples.
実施例
第１図に本発明の製造方法を実施するために使
用する装置の一実施例を示す。10-5Torrの真空
槽１内に直径300mmの蒸着円筒２と蒸発源３を対
向して配置する。蒸発源３は電子ビーム４により
加熱蒸発させる。５は材料容器である。高分子基
板６には幅200mm、長さ1000m、厚さ15μｍのポ
リエチレンテレフタレートフイルムを用いた。基
板６は巻出し軸７からフリーローラ８を経て蒸着
円筒２に沿つて再び別のフリーローラ９を通り巻
取り軸１０に到る。したがつて基板６の走行方
向、軸、蒸着円筒の回転方向は矢印方向となる。
この基板走行系において、基板６が蒸着円筒２に
沿つて移動する部分で、蒸発源３から蒸発した磁
性材料が基板表面に磁性層を形成するのに有効な
蒸発原子群１１の範囲内で磁性材料が蒸着され
る。本実施例では、基板６の走行速度を20m／
minで行つたが、これは任意の走行速度に設定で
きる。上述した蒸着装置、蒸着条件下において磁
性層を形成するのであるが、本実施例では第１図
に示すように蒸着円筒２の下方の左右に酸素ノズ
ル１２，１３を配置した。この酸素ノズル１２，
１３は酸素１２′，１３′を供給するためのもの
で、磁性薄膜に高い保磁力を得るためである。ま
た第１図中、酸素ノズル１２，１３を２つ示した
のは、酸素ノズル位置の検討を示すためであり、
製造過程では以下に述べる結果より酸素ノズル１
３のみでよい。酸素ノズル１２，１３は、長さが
300mm、外径30φのパイプに50mmのピツチで0.5φ
の小孔をあけて各々の小孔から酸素が均一に噴出
するように構成したものである。なお、図におい
て、１４は防着板である。そして真空排気系は省
略している。Embodiment FIG. 1 shows an embodiment of the apparatus used to carry out the manufacturing method of the present invention. An evaporation cylinder 2 with a diameter of 300 mm and an evaporation source 3 are placed facing each other in a vacuum chamber 1 at 10 -5 Torr. The evaporation source 3 is heated and evaporated by an electron beam 4. 5 is a material container. As the polymer substrate 6, a polyethylene terephthalate film having a width of 200 mm, a length of 1000 m, and a thickness of 15 μm was used. The substrate 6 passes from the unwinding shaft 7 to the free roller 8, along the vapor deposition cylinder 2, passes through another free roller 9 again, and reaches the winding shaft 10. Therefore, the direction of travel of the substrate 6, the axis, and the direction of rotation of the deposition cylinder are in the direction of the arrow.
In this substrate traveling system, in a portion where the substrate 6 moves along the deposition cylinder 2, the magnetic material evaporated from the evaporation source 3 becomes magnetic within the range of the evaporated atomic group 11 that is effective for forming a magnetic layer on the substrate surface. Material is deposited. In this embodiment, the traveling speed of the board 6 is set to 20 m/
I set it to min, but this can be set to any running speed. A magnetic layer is formed using the above-mentioned vapor deposition apparatus under the vapor deposition conditions. In this example, oxygen nozzles 12 and 13 were arranged on the left and right sides below the vapor deposition cylinder 2, as shown in FIG. This oxygen nozzle 12,
Reference numeral 13 is for supplying oxygen 12' and 13' to obtain a high coercive force in the magnetic thin film. In addition, the reason why two oxygen nozzles 12 and 13 are shown in FIG. 1 is to show the consideration of the oxygen nozzle position.
In the manufacturing process, oxygen nozzle 1 was selected based on the results described below.
Only 3 is enough. The length of the oxygen nozzles 12 and 13 is
300mm, 0.5φ with a 50mm pitch on a pipe with an outer diameter of 30φ
The structure is such that oxygen is uniformly ejected from each small hole. In addition, in the figure, 14 is an adhesion prevention plate. And the vacuum exhaust system is omitted.
磁性層はコバルトを300Å蒸着して得たが、蒸
着期間中、ノズルから酸素量を0.2〜1.0／min
の範囲で変化させた。ノズル１２およびノズル１
３からの酸素供給量と保磁力Hcの関係を第２図
に示す。 The magnetic layer was obtained by depositing 300 Å of cobalt, and during the deposition period, the amount of oxygen from the nozzle was 0.2 to 1.0/min.
It was varied within the range of. Nozzle 12 and nozzle 1
Figure 2 shows the relationship between the amount of oxygen supplied from No. 3 and the coercive force Hc.
(A) ノズル１２のみ使用の場合
ノズル１２から酸素を矢印１２′の方向に向
けて供給した場合の保磁力Hc変化を第２図の
Ａに示す。酸素供給量0.2／minから増加さ
せることにより保磁力も増加するが、酸素供給
量が0.4〜0.5／minより増加させると保磁力
Hcは減少方向となつた。(A) When only the nozzle 12 is used A in FIG. 2 shows the change in coercive force Hc when oxygen is supplied from the nozzle 12 in the direction of arrow 12'. Coercive force also increases by increasing the oxygen supply rate from 0.2/min, but if the oxygen supply rate increases from 0.4 to 0.5/min, the coercive force increases.
Hc started to decrease.
(B) ノズル１３のみ使用の場合
ノズル１３から酸素を矢印１３′の方向に向
けて供給した場合の保磁力Hc変化を第２図の
Ｂに示す。この酸素供給方法によれば、酸素量
0.2〜1.0／minの範囲内では保磁力Hcは増加
している。過多の酸素供給になると、酸素分圧
が高くなり、所定の磁性層厚が得られなくな
り、検討に値しなかつた。(B) When using only the nozzle 13 B in FIG. 2 shows the change in coercive force Hc when oxygen is supplied from the nozzle 13 in the direction of arrow 13'. According to this oxygen supply method, the amount of oxygen
The coercive force Hc increases within the range of 0.2 to 1.0/min. If too much oxygen was supplied, the oxygen partial pressure would become high, making it impossible to obtain a predetermined magnetic layer thickness, which was not worth considering.
(C) ノズル１２，１３の付近にてノズル位置を変
え、また酸素噴出角度を水平に対して±40゜に
変化させて酸素供給量と保磁力Hcの関係を検
討したが、第２図のＡ，Ｂの傾向と大差はなか
つた。(C) We examined the relationship between the oxygen supply amount and coercive force Hc by changing the nozzle position near nozzles 12 and 13 and by changing the oxygen jet angle to ±40° with respect to the horizontal. There was no significant difference between trends A and B.
以上の実施例および検討結果に示したように、
薄膜による磁気記録媒体を製造するに際し、高い
保磁力を有する磁性層を得るために酸素を供給す
る場合は、蒸着円筒の回転方向と逆方向に沿つた
酸素の流れが生じる供給方法が、第１図に示した
ノズル１３附近において水平に対し±40゜の噴出
角度を持つて基板の走行と逆方向に酸素を供給す
ることが、高保磁力を得るのに効果的な方法であ
ることが分つた。 As shown in the above examples and study results,
When supplying oxygen to obtain a magnetic layer with a high coercive force when producing a thin film magnetic recording medium, the first supply method is one in which oxygen flows in the direction opposite to the rotational direction of the deposition cylinder. It has been found that supplying oxygen in the direction opposite to the direction of travel of the substrate at an ejection angle of ±40° with respect to the horizontal near nozzle 13 shown in the figure is an effective method for obtaining a high coercive force. .
本発明は上記の実施例に限定されるものではな
く、通常行われる、入射角限定のマスクを利用す
場合についても同様の効果があり、Co100％、
Co80％Ni20％の合金について膜厚0.02μｍ〜0.25
μｍ、入射角０゜から75゜までの範囲について
も、従来法で得られる保磁力の２倍〜３倍の高い
保磁力が得られると共に角形性、実用耐久性に優
れた磁気記録媒体を得ることができるものであ
る。 The present invention is not limited to the above embodiments, and the same effect can be obtained even when using a mask with a limited incident angle, which is commonly used.
Film thickness 0.02μm to 0.25 for Co80%Ni20% alloy
μm and incident angle in the range from 0° to 75°, a magnetic recording medium is obtained that can obtain a coercive force that is two to three times higher than that obtained by conventional methods, and has excellent squareness and practical durability. It is something that can be done.
なお、実施例中の装置の形状、寸法に限定され
ることなく、蒸発源の加熱方法も電子ビームに限
らず、例えば高周波誘導加熱等の方法も可能であ
り、基板の走行方向も実施例と逆方向でもよく、
ノズル位置は基板の走行方向にあわせて移動する
もので、基板と酸素の相対関係が一定であれば本
発明の範囲内に入るものである。 Note that the shape and dimensions of the apparatus in the examples are not limited, and the method of heating the evaporation source is not limited to electron beams, but methods such as high-frequency induction heating are also possible, and the running direction of the substrate is also the same as in the examples. It can also be in the opposite direction,
The nozzle position moves in accordance with the traveling direction of the substrate, and as long as the relative relationship between the substrate and oxygen is constant, it falls within the scope of the present invention.
以上のような本発明の磁気記録媒体の製造方法
によれば、次のような利点がある。 According to the method of manufacturing a magnetic recording medium of the present invention as described above, there are the following advantages.
(1) 高保磁力の磁性薄膜が容易に得られ、高密度
記録媒体の大量生産が可能である。(1) Magnetic thin films with high coercive force can be easily obtained, and high-density recording media can be mass-produced.
(2) したがつてコストの低減が図れ、工業的価値
が大である。(2) Therefore, the cost can be reduced and the industrial value is great.
(3) 酸素の供給方法は簡単である。(3) The method of supplying oxygen is simple.
第１図は本発明の製造方法を実施するために使
用する装置の概略断面正面図、第２図は酸素供給
量に対する磁気記録媒体の保磁力特性図である。
１……真空槽、２……蒸着円筒、３……蒸発
源、６……高分子基板、１１……蒸発原子群、１
３……酸素ノズル。
FIG. 1 is a schematic cross-sectional front view of an apparatus used to carry out the manufacturing method of the present invention, and FIG. 2 is a diagram showing coercive force characteristics of a magnetic recording medium with respect to oxygen supply amount. 1... Vacuum chamber, 2... Evaporation cylinder, 3... Evaporation source, 6... Polymer substrate, 11... Evaporation atomic group, 1
3...Oxygen nozzle.
Claims (1)
る高分子基板の表面に連続的に蒸発源からの磁性
材料を差し向け、磁性層を形成する磁気記録媒体
の製造方法において、前記高分子基板の磁性層形
成部分に酸素を供給し、かつ前記磁性層形成部分
における前記酸素の流れを前記高分子基板の走行
方向と逆になるようにしたことを特徴とする磁気
記録媒体の製造方法。1. A method for producing a magnetic recording medium in which a magnetic layer is formed by continuously directing a magnetic material from an evaporation source onto the surface of a polymer substrate moving along the circumferential surface of an evaporation cylinder in a vacuum chamber. A method for producing a magnetic recording medium, characterized in that oxygen is supplied to a magnetic layer forming portion of a molecular substrate, and the flow of the oxygen in the magnetic layer forming portion is opposite to the running direction of the polymer substrate. .
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP16388580A JPS5788531A (en) | 1980-11-20 | 1980-11-20 | Manufacture for magnetic recording medium |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP16388580A JPS5788531A (en) | 1980-11-20 | 1980-11-20 | Manufacture for magnetic recording medium |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS5788531A JPS5788531A (en) | 1982-06-02 |
| JPS6156563B2 true JPS6156563B2 (en) | 1986-12-03 |
Family
ID=15782643
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP16388580A Granted JPS5788531A (en) | 1980-11-20 | 1980-11-20 | Manufacture for magnetic recording medium |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS5788531A (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB2536252B (en) * | 2015-03-10 | 2018-10-10 | Bobst Manchester Ltd | Method of operating a vacuum coater for coating a web |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5342010A (en) * | 1976-09-28 | 1978-04-17 | Matsushita Electric Ind Co Ltd | Preparation of magnetic recording medium |
| JPS5419199A (en) * | 1977-07-12 | 1979-02-13 | Matsushita Electric Ind Co Ltd | Magnetic recording medium porcess |
| JPS5629A (en) * | 1979-06-15 | 1981-01-06 | Ulvac Corp | Vacuum-evaporated film type magnetic recording substance and its manufacture |
-
1980
- 1980-11-20 JP JP16388580A patent/JPS5788531A/en active Granted
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5342010A (en) * | 1976-09-28 | 1978-04-17 | Matsushita Electric Ind Co Ltd | Preparation of magnetic recording medium |
| JPS5419199A (en) * | 1977-07-12 | 1979-02-13 | Matsushita Electric Ind Co Ltd | Magnetic recording medium porcess |
| JPS5629A (en) * | 1979-06-15 | 1981-01-06 | Ulvac Corp | Vacuum-evaporated film type magnetic recording substance and its manufacture |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS5788531A (en) | 1982-06-02 |
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