JPH04291018A - Magnetic recording medium and production thereof - Google Patents
Magnetic recording medium and production thereofInfo
- Publication number
- JPH04291018A JPH04291018A JP5703091A JP5703091A JPH04291018A JP H04291018 A JPH04291018 A JP H04291018A JP 5703091 A JP5703091 A JP 5703091A JP 5703091 A JP5703091 A JP 5703091A JP H04291018 A JPH04291018 A JP H04291018A
- Authority
- JP
- Japan
- Prior art keywords
- layer
- electroless plating
- glass substrate
- recording medium
- magnetic
- 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
- 238000004519 manufacturing process Methods 0.000 title claims description 10
- 239000000758 substrate Substances 0.000 claims abstract description 65
- 239000011521 glass Substances 0.000 claims abstract description 52
- 238000007772 electroless plating Methods 0.000 claims abstract description 50
- 230000003746 surface roughness Effects 0.000 claims abstract description 5
- 238000010438 heat treatment Methods 0.000 claims description 19
- 238000000034 method Methods 0.000 claims description 17
- 239000010410 layer Substances 0.000 description 52
- 238000007747 plating Methods 0.000 description 24
- 238000004544 sputter deposition Methods 0.000 description 15
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 11
- 229910018104 Ni-P Inorganic materials 0.000 description 9
- 229910018536 Ni—P Inorganic materials 0.000 description 9
- 238000005260 corrosion Methods 0.000 description 7
- 230000007797 corrosion Effects 0.000 description 7
- 238000005406 washing Methods 0.000 description 7
- 230000000052 comparative effect Effects 0.000 description 6
- 238000010828 elution Methods 0.000 description 6
- 239000000203 mixture Substances 0.000 description 5
- 229910052782 aluminium Inorganic materials 0.000 description 4
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 4
- 239000003599 detergent Substances 0.000 description 4
- 230000007935 neutral effect Effects 0.000 description 4
- 239000011241 protective layer Substances 0.000 description 4
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 3
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 3
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 3
- 239000005354 aluminosilicate glass Substances 0.000 description 3
- 229910052799 carbon Inorganic materials 0.000 description 3
- 229910052802 copper Inorganic materials 0.000 description 3
- 239000010949 copper Substances 0.000 description 3
- 238000005238 degreasing Methods 0.000 description 3
- 229910052710 silicon Inorganic materials 0.000 description 3
- 239000010703 silicon Substances 0.000 description 3
- 239000005361 soda-lime glass Substances 0.000 description 3
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 description 2
- -1 C a Inorganic materials 0.000 description 2
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 description 2
- 229910002666 PdCl2 Inorganic materials 0.000 description 2
- 229910021626 Tin(II) chloride Inorganic materials 0.000 description 2
- MCMNRKCIXSYSNV-UHFFFAOYSA-N Zirconium dioxide Chemical compound O=[Zr]=O MCMNRKCIXSYSNV-UHFFFAOYSA-N 0.000 description 2
- 230000004913 activation Effects 0.000 description 2
- 239000003513 alkali Substances 0.000 description 2
- 239000007864 aqueous solution Substances 0.000 description 2
- 238000005513 bias potential Methods 0.000 description 2
- 239000005388 borosilicate glass Substances 0.000 description 2
- 229910052804 chromium Inorganic materials 0.000 description 2
- 238000002845 discoloration Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 239000000314 lubricant Substances 0.000 description 2
- PIBWKRNGBLPSSY-UHFFFAOYSA-L palladium(II) chloride Chemical compound Cl[Pd]Cl PIBWKRNGBLPSSY-UHFFFAOYSA-L 0.000 description 2
- 239000005368 silicate glass Substances 0.000 description 2
- HUAUNKAZQWMVFY-UHFFFAOYSA-M sodium;oxocalcium;hydroxide Chemical compound [OH-].[Na+].[Ca]=O HUAUNKAZQWMVFY-UHFFFAOYSA-M 0.000 description 2
- 239000000243 solution Substances 0.000 description 2
- 235000011150 stannous chloride Nutrition 0.000 description 2
- AXZWODMDQAVCJE-UHFFFAOYSA-L tin(II) chloride (anhydrous) Chemical compound [Cl-].[Cl-].[Sn+2] AXZWODMDQAVCJE-UHFFFAOYSA-L 0.000 description 2
- 229920000298 Cellophane Polymers 0.000 description 1
- 229910052684 Cerium Inorganic materials 0.000 description 1
- 229910020707 Co—Pt Inorganic materials 0.000 description 1
- 229910020515 Co—W Inorganic materials 0.000 description 1
- 229910052693 Europium Inorganic materials 0.000 description 1
- YCKRFDGAMUMZLT-UHFFFAOYSA-N Fluorine atom Chemical compound [F] YCKRFDGAMUMZLT-UHFFFAOYSA-N 0.000 description 1
- WHXSMMKQMYFTQS-UHFFFAOYSA-N Lithium Chemical compound [Li] WHXSMMKQMYFTQS-UHFFFAOYSA-N 0.000 description 1
- 229910052779 Neodymium Inorganic materials 0.000 description 1
- 229910052777 Praseodymium Inorganic materials 0.000 description 1
- 229910052772 Samarium Inorganic materials 0.000 description 1
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 1
- 230000002411 adverse Effects 0.000 description 1
- 239000000956 alloy Substances 0.000 description 1
- 229910045601 alloy Inorganic materials 0.000 description 1
- 229910052787 antimony Inorganic materials 0.000 description 1
- 229910052786 argon Inorganic materials 0.000 description 1
- 229910052785 arsenic Inorganic materials 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 229910052796 boron Inorganic materials 0.000 description 1
- 229910002092 carbon dioxide Inorganic materials 0.000 description 1
- 239000001569 carbon dioxide Substances 0.000 description 1
- 238000003486 chemical etching Methods 0.000 description 1
- 238000003426 chemical strengthening reaction Methods 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 238000002425 crystallisation Methods 0.000 description 1
- 230000008025 crystallization Effects 0.000 description 1
- 235000014113 dietary fatty acids Nutrition 0.000 description 1
- 238000009792 diffusion process Methods 0.000 description 1
- 239000003822 epoxy resin Substances 0.000 description 1
- 229930195729 fatty acid Natural products 0.000 description 1
- 239000000194 fatty acid Substances 0.000 description 1
- 150000004665 fatty acids Chemical class 0.000 description 1
- 229910052731 fluorine Inorganic materials 0.000 description 1
- 239000011737 fluorine Substances 0.000 description 1
- 229910052735 hafnium Inorganic materials 0.000 description 1
- 229910052741 iridium Inorganic materials 0.000 description 1
- 238000010030 laminating Methods 0.000 description 1
- 239000004973 liquid crystal related substance Substances 0.000 description 1
- 229910052744 lithium Inorganic materials 0.000 description 1
- 230000001050 lubricating effect Effects 0.000 description 1
- 239000010687 lubricating oil Substances 0.000 description 1
- 238000001755 magnetron sputter deposition Methods 0.000 description 1
- 230000008018 melting Effects 0.000 description 1
- 238000002844 melting Methods 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 229910052759 nickel Inorganic materials 0.000 description 1
- 229910052758 niobium Inorganic materials 0.000 description 1
- 229910052762 osmium Inorganic materials 0.000 description 1
- 239000010702 perfluoropolyether Substances 0.000 description 1
- 229910052698 phosphorus Inorganic materials 0.000 description 1
- 229910052697 platinum Inorganic materials 0.000 description 1
- 229920000647 polyepoxide Polymers 0.000 description 1
- 229910001414 potassium ion Inorganic materials 0.000 description 1
- 239000000843 powder Substances 0.000 description 1
- 230000001681 protective effect Effects 0.000 description 1
- 229920005989 resin Polymers 0.000 description 1
- 239000011347 resin Substances 0.000 description 1
- 229910052702 rhenium Inorganic materials 0.000 description 1
- 229910052703 rhodium Inorganic materials 0.000 description 1
- 229910052707 ruthenium Inorganic materials 0.000 description 1
- 229910052814 silicon oxide Inorganic materials 0.000 description 1
- 229910052709 silver Inorganic materials 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 229910052715 tantalum Inorganic materials 0.000 description 1
- 229910052719 titanium Inorganic materials 0.000 description 1
- 229910052721 tungsten Inorganic materials 0.000 description 1
- 229910052720 vanadium Inorganic materials 0.000 description 1
- 229910052727 yttrium Inorganic materials 0.000 description 1
- 229910052726 zirconium Inorganic materials 0.000 description 1
Landscapes
- Magnetic Record Carriers (AREA)
- Manufacturing Of Magnetic Record Carriers (AREA)
Abstract
Description
【０００１】0001
【産業上の利用分野】本発明は、耐候性の著しく向上さ
れたガラス基板を用いた磁気記録媒体及びその製造法に
関するものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic recording medium using a glass substrate with significantly improved weather resistance and a method for manufacturing the same.
【０００２】0002
【従来の技術】磁気ディスク用基板としてガラス基板を
用いることは公知であり、例えば、特公昭４３−４６２
１号にてメッキ法にて磁性膜を作製することが提案され
ており、また、特開昭５９−１７１０３１号に於いては
ガラス基板にスパッタ法にてＣｏ−Ｐｔ磁性膜を形成し
た磁気記録媒体が提案されている。BACKGROUND OF THE INVENTION It is known to use a glass substrate as a substrate for a magnetic disk.
No. 1 proposed the production of a magnetic film by a plating method, and JP-A-59-171031 proposed a method for magnetic recording in which a Co-Pt magnetic film was formed on a glass substrate by a sputtering method. medium is proposed.
【０００３】しかし、実用的にはいくつかの問題があり
、汎用的に用いられていない。その一つの問題として、
以下に記載する如く耐候性が劣る問題がある。つまり、
ガラス基板は通常のアルミニウム基板にＮｉ−Ｐ無電解
メッキを施した基板と異なり、耐水性が劣り、水により
侵食され易く、かつ、ガラス基板のアルカリ成分が表面
に溶出して来ることが例えば「ガラス表面設計」（近代
編集社）Ｐ．４３およびＰ．１５６に記載されている。[0003] However, there are some problems in practical use, and this method is not widely used. One of the issues is that
As described below, there is a problem of poor weather resistance. In other words,
Glass substrates are different from ordinary aluminum substrates with Ni-P electroless plating, and have poor water resistance and are easily eroded by water.Also, the alkaline components of the glass substrates may be eluted to the surface, for example. "Glass Surface Design" (Kaidai Editsha) P. 43 and P. 156.
【０００４】実用面での対策として液晶用のガラス基板
にはアルカリ成分の溶出防止のため、有機シリコン溶液
を塗布してシリコン酸化膜の薄膜層を形成することを工
業的に実施したり、アルカリ成分の溶出量がソーダライ
ムシリケートガラスに比べ少ないホウケイ酸ガラスが使
用されている。但し、コスト的に問題があり、ホウケイ
酸ガラスの価格は高い。As a practical countermeasure, in order to prevent the elution of alkali components on glass substrates for liquid crystals, it is industrially carried out to form a thin layer of silicon oxide film by applying an organic silicon solution. Borosilicate glass is used because the amount of components eluted is smaller than that of soda lime silicate glass. However, there is a cost problem, and the price of borosilicate glass is high.
【０００５】ガラス基板を磁気記録媒体用基板として用
いた場合も例外でなく、多湿環境下で磁気ディスクの内
外周等に腐食が発生し、その改善のために多くの提案が
されている。例えば、特開昭６３−２６９３１９号では
、磁気ディスク周縁部の磁気記録層とガラス露出部分に
エポキシ樹脂等を塗布することが提案され、また、特開
昭６４−４２０２５号では、ガラス基板の組成を特定の
組成に変更することが提案されている。しかし、組成変
更は製造条件の変更であり、溶解温度が高くなる等製造
上の問題が発生すると共に、コスト的にも高くなる。
また、樹脂や有機シリコン溶液の塗布は磁気ディスクの
平坦度に悪影響を与える。最近は磁気ディスクの高容量
化のためヘッドが低浮上化しており、かつ、磁気ディス
クの最外周まで飛行するため、ヘッドクラッシユの原因
ともなり、好ましくない。[0005] When a glass substrate is used as a substrate for a magnetic recording medium, corrosion occurs on the inner and outer peripheries of the magnetic disk in a humid environment, and many proposals have been made to improve this problem. For example, JP-A No. 63-269319 proposes applying epoxy resin or the like to the magnetic recording layer and the exposed portion of the glass at the periphery of the magnetic disk, and JP-A No. 64-42025 proposes the composition of the glass substrate. It has been proposed to change the composition of However, changing the composition is a change in manufacturing conditions, which causes manufacturing problems such as an increase in melting temperature, and also increases costs. Furthermore, the application of resin or organic silicon solution adversely affects the flatness of the magnetic disk. Recently, the flying height of the head has become lower due to the increase in the capacity of magnetic disks, and since the head flies to the outermost periphery of the magnetic disk, this is undesirable as it may cause a head crash.
【０００６】[0006]
【発明が解決しようとする課題】前述のように、通常の
ガラス基板、ソーダライムシリケートガラス、アルミノ
シリケートガラス等を磁気記録媒体基板として用いる場
合、基板から溶出するアルカリ成分による磁性膜の腐食
が問題となる。アルカリ成分の溶出は単に、磁気ディス
クの周辺部のガラス基板露出部のみならず製造工程で発
生した磁気ディスク記録領域での微小な膜未形成部でも
発生するため、ガラス基板全面を均一に被覆することが
望ましい。[Problems to be Solved by the Invention] As mentioned above, when a normal glass substrate, soda lime silicate glass, aluminosilicate glass, etc. is used as a magnetic recording medium substrate, corrosion of the magnetic film due to alkali components eluted from the substrate is a problem. becomes. The elution of alkaline components occurs not only in the exposed areas of the glass substrate at the periphery of the magnetic disk, but also in minute areas where no film is formed in the recording area of the magnetic disk that occurs during the manufacturing process, so the entire surface of the glass substrate must be uniformly coated. This is desirable.
【０００７】本発明者らは、アルミニウム基板と同様に
ガラス基板全面に無電解Ｎｉ−Ｐメッキ層を形成するこ
とを試みたが、従来の手法ではガラス基板は無電解メッ
キ層と密着性が悪く、鏡面研磨したガラス基板には、無
電解Ｎｉ−Ｐメッキ層は高々３００Åの厚さしかメッキ
出来ず、それ以上の厚さではメッキ中や水洗中にメッキ
膜の▲剥▼離が生じた。高々３００Åでは、アルカリ成
分の溶出防止膜としては不十分であった。[0007] The present inventors attempted to form an electroless Ni-P plating layer on the entire surface of a glass substrate in the same way as an aluminum substrate, but with the conventional method, the adhesion of the glass substrate to the electroless plating layer was poor. On a mirror-polished glass substrate, an electroless Ni--P plating layer could only be plated to a thickness of 300 Å at most, and if the thickness was greater than that, the plating film would peel off during plating or washing with water. A thickness of at most 300 Å was insufficient as a film for preventing elution of alkaline components.
【０００８】ガラス基板との密着性を改善するために、
例えば、特開昭４８−９４４０３号、特開昭４９−１２
２７０７号でガラス基板に金属粉を混ぜたりした特殊ガ
ラスが提案されている。しかし、この提案は、製造上の
問題、コスト及びガラス基板の平坦度の観点から実用的
ではない。また、特開昭６１−５４０１８号では特定の
Ｎｉ−Ｐ無電解メッキ浴にて内部ひずみの小さいＮｉ−
Ｐメッキ膜をガラス基板の上に設けることが提案されて
いる。しかし、この場合も高々２００〜３００Åの膜厚
が密着性よく形成されているだけであり、アルカリ成分
の溶出を防止するためには、膜厚が不十分である。[0008] In order to improve the adhesion with the glass substrate,
For example, JP-A-48-94403, JP-A-49-12
No. 2707 proposes a special glass in which metal powder is mixed into a glass substrate. However, this proposal is not practical from the viewpoint of manufacturing problems, cost, and flatness of the glass substrate. In addition, in JP-A No. 61-54018, Ni-P has a small internal strain in a specific Ni-P electroless plating bath.
It has been proposed to provide a P plating film on a glass substrate. However, in this case as well, a film thickness of 200 to 300 Å at most is formed with good adhesion, and the film thickness is insufficient to prevent elution of alkaline components.
【０００９】[0009]
【課題を解決するための手段】本発明は、所定の膜厚の
無電解メッキ層を密着性よくしかも安価に実用的な方法
で形成しアルカリ成分の溶出による腐食問題を解決し耐
候性を改善した、ガラス基板を用いた磁気記録媒体及び
その製造方法を提供することを目的とする。[Means for Solving the Problems] The present invention solves the problem of corrosion due to the elution of alkaline components and improves weather resistance by forming an electroless plating layer of a predetermined thickness with good adhesion, at low cost, and in a practical manner. An object of the present invention is to provide a magnetic recording medium using a glass substrate and a manufacturing method thereof.
【００１０】即ち、本発明の要旨は、無電解メッキ法に
より厚さ１０００Å以上の無電解メッキ層を積層したガ
ラス基板の上に、磁性層を設けたことを特徴とする磁気
記録媒体、及び、中心線平均粗さＲａ１０Å以下で最大
高さＲｍａｘ１５０Å以下の表面粗さのガラス基板に、
初めに無電解メッキ法により厚さ３００Å以下の無電解
メッキ層を設けた後に１５０〜４００℃の温度で熱処理
を施し、更にその上に無電解メッキ法により無電解メッ
キ層を形成した後、１５０〜４００℃の温度で熱処理を
施すことによって総厚み１０００Å以上の無電解メッキ
層を設けたガラス基板の上に、磁性層を設けることを特
徴とする磁気記録媒体の製造法、に存する。That is, the gist of the present invention is to provide a magnetic recording medium characterized in that a magnetic layer is provided on a glass substrate on which an electroless plating layer with a thickness of 1000 Å or more is laminated by an electroless plating method, and A glass substrate with a surface roughness of center line average roughness Ra of 10 Å or less and maximum height Rmax of 150 Å or less,
First, an electroless plating layer with a thickness of 300 Å or less is provided by an electroless plating method, and then heat treatment is performed at a temperature of 150 to 400°C. The present invention relates to a method for manufacturing a magnetic recording medium, characterized in that a magnetic layer is provided on a glass substrate provided with an electroless plating layer having a total thickness of 1000 Å or more by heat treatment at a temperature of ~400°C.
【００１１】以下に本発明について更に詳細に説明する
。本発明の磁気記録媒体は、無電解メッキ法により厚さ
１０００Å以上の無電解メッキ層を設けたガラス基板の
上に、磁性層を設けたことを特徴とする。The present invention will be explained in more detail below. The magnetic recording medium of the present invention is characterized in that a magnetic layer is provided on a glass substrate on which an electroless plating layer with a thickness of 1000 Å or more is provided by an electroless plating method.
【００１２】本発明の磁気記録媒体は、例えば、中心線
平均粗さＲａ１０Å以下で最大高さＲｍａｘ１５０Å以
下の表面粗さのガラス基板に、初めに無電解メッキ法に
より厚さ３００Å以下の無電解メッキ層を設けた後に１
５０〜４００℃の温度で熱処理を施し、更にその上に無
電解メッキ法により無電解メッキ層を形成した後１５０
〜４００℃の温度で熱処理を施すことによって総厚み１
０００Å以上の無電解メッキ層を設けたガラス基板の上
に磁性層を設けることにより得ることができる。In the magnetic recording medium of the present invention, for example, a glass substrate having a surface roughness of center line average roughness Ra of 10 Å or less and maximum height Rmax of 150 Å or less is first electrolessly plated to a thickness of 300 Å or less by an electroless plating method. 1 after applying the layer
After heat treatment at a temperature of 50 to 400°C, and further forming an electroless plating layer on top of it by an electroless plating method,
The total thickness is 1 by heat treatment at a temperature of ~400℃.
It can be obtained by providing a magnetic layer on a glass substrate provided with an electroless plating layer of 000 Å or more.
【００１３】ガラス基板の種類としては、特に制限はな
いが通常のソーダライムガラス、アルミノシリケートガ
ラス、また、結晶化ガラスとしてリチウム系ガラス（例
えば日本電気硝子社製「ＭＬ−５」）等を用いることが
できる。通常はコストの面から化学強化した安価なソー
ダライムガラス、アルミノシリケートガラスを鏡面研磨
して用いる。The type of glass substrate is not particularly limited, but ordinary soda lime glass, aluminosilicate glass, and lithium-based glass (for example, "ML-5" manufactured by Nippon Electric Glass Co., Ltd.) as crystallized glass may be used. be able to. Usually, from a cost perspective, inexpensive chemically strengthened soda lime glass or aluminosilicate glass is mirror-polished.
【００１４】鏡面研磨したガラス基板の表面粗さは、接
触式粗さ計の測定で中心線平均粗さＲａ１０Å以下、最
大高さＲｍａｘ１５０Å以下に仕上げられているものが
好ましい。本発明の磁気記録媒体は上記したようなガラ
ス基板を用いて例えば次のようにして作製される。The surface roughness of the mirror-polished glass substrate is preferably such that the center line average roughness Ra is 10 Å or less and the maximum height Rmax is 150 Å or less as measured by a contact roughness meter. The magnetic recording medium of the present invention is manufactured using the glass substrate as described above, for example, in the following manner.
【００１５】上記したガラス基板を通常の中性洗剤脱脂
を行い、次に常法のＳｎＣｌ２ 浴、ＰｄＣｌ２ 浴に
て活性化処理を行なった後で、通常の無電解メッキ浴に
て厚さ３００Å以下の第一層目の無電解メッキ膜を形成
後、クリーンな乾燥器にて１５０〜４００℃の温度にて
熱処理を行う。The above-mentioned glass substrate is degreased with a normal neutral detergent, then activated in a normal SnCl2 bath or PdCl2 bath, and then processed to a thickness of 300 Å or less in a normal electroless plating bath. After forming the first layer of electroless plating film, heat treatment is performed at a temperature of 150 to 400° C. in a clean dryer.
【００１６】この熱処理後再度、中性洗剤脱脂を行った
後、無電解メッキ浴にて第二層目の無電解メッキ膜を総
膜厚み１０００Å以上の膜厚まで形成し、また１５０〜
４００℃の温度にて熱処理を行う。なお、上記第二層目
の無電解メッキ膜の形成においては、これを中断して上
記した１５０〜４００℃での熱処理を適宜行なってもよ
い。After this heat treatment, degreasing with a neutral detergent is performed again, and then a second layer of electroless plating film is formed in an electroless plating bath to a total film thickness of 1000 Å or more.
Heat treatment is performed at a temperature of 400°C. In addition, in the formation of the second-layer electroless plating film, this may be interrupted and the above-described heat treatment at 150 to 400° C. may be performed as appropriate.
【００１７】無電解メッキは従来のアルミニウム基板と
同様な非磁性のＮｉ−Ｐメッキでも良いし、銅メッキで
もよい。また、各メッキ層の種類を変えてもよい。但し
、非磁性膜がよい。一層目の膜厚が３００Åを越えると
メッキ途中や水洗中に部分的に膜▲剥▼離が生じてくる
。一層目の膜厚は約２００〜３００Åとすることが好ま
しい。総メッキ膜厚としては耐候性上１０００Å以上が
必要である。膜厚の上限は特にないが１μｍ以下が密着
性の点から好ましい。中でも１５００Å以上５０００Å
以下がより好ましい。The electroless plating may be non-magnetic Ni--P plating similar to conventional aluminum substrates, or copper plating. Further, the type of each plating layer may be changed. However, a non-magnetic film is preferable. If the thickness of the first layer exceeds 300 Å, partial peeling of the film will occur during plating or during water washing. The thickness of the first layer is preferably about 200 to 300 Å. The total plating film thickness must be 1000 Å or more for weather resistance. Although there is no particular upper limit to the film thickness, it is preferably 1 μm or less from the viewpoint of adhesion. Among them, 1500 Å or more and 5000 Å
The following are more preferable.
【００１８】熱処理温度は１５０〜４００℃、好ましく
は１５０〜３００℃の範囲である。１５０℃未満では効
果が少なく、４００℃を越えると化学強化層のカリウム
イオンの拡散が生じて強度低下が起こる。熱処理時間は
３０分以上、中でも３０〜６０分が好ましい。なお、無
電解メッキは例えばディスク内周等でディスクを保持し
、回転させながら無電解メッキ浴に浸漬させること等に
よって全面に均一に無電解メッキ膜が形成されるように
するのが好ましい。[0018] The heat treatment temperature is in the range of 150 to 400°C, preferably 150 to 300°C. If the temperature is lower than 150°C, the effect will be small, and if the temperature exceeds 400°C, diffusion of potassium ions in the chemically strengthened layer will occur, resulting in a decrease in strength. The heat treatment time is preferably 30 minutes or more, preferably 30 to 60 minutes. In electroless plating, it is preferable to hold the disk by its inner periphery, for example, and immerse it in an electroless plating bath while rotating, so that an electroless plating film is uniformly formed over the entire surface.
【００１９】このようにして１０００Å以上の無電解メ
ッキ層を設けたガラス基板を、スパッタ装置に入れ、必
要に応じて下引き層をスパッタ成膜した後磁性層を設け
る。また、磁性層の上に、更に必要に応じて、保護層及
び／又は潤滑層を設けることができる。スパッタ成膜さ
れる下引き層はＣｒ層、Ｔｉ層等で、磁性層の磁気特性
を良好にするために用いる。The glass substrate thus provided with an electroless plating layer of 1000 Å or more is placed in a sputtering apparatus, and if necessary, an undercoat layer is formed by sputtering, and then a magnetic layer is provided. Moreover, a protective layer and/or a lubricating layer can be provided on the magnetic layer, if necessary. The undercoat layer formed by sputtering is a Cr layer, a Ti layer, etc., and is used to improve the magnetic properties of the magnetic layer.
【００２０】下引き層の膜厚は通常、５００〜３０００
Å程度とする。磁性層組成としてはスパッタ法によるＣ
ｏ−Ｃｒ、Ｃｏ−Ｃｒ−Ｘ、Ｃｏ−Ｎｉ−Ｘ、Ｃｏ−Ｗ
−Ｘ等で表わされるＣｏを主成分とするＣｏ系合金磁性
膜が使用できる。ここでＸとしてはＬｉ、Ｓｉ、Ｂ、Ｃ
ａ、Ｔｉ、Ｖ、Ｃｒ、Ｎｉ、Ａｓ、Ｙ、Ｚｒ、Ｎｂ、Ｍ
ｏ、Ｒｕ、Ｒｈ、Ａｇ、Ｓｂ、Ｈｆ、Ｔａ、Ｗ、Ｒｅ、
Ｏｓ、Ｉｒ、Ｐｔ、Ａｕ、Ｌａ、Ｃｅ、Ｐｒ、Ｎｄ、Ｐ
ｍ、Ｓｍ及びＥｕよりなる群から選ばれる１種又は２種
以上の元素が用いられる。磁性層の膜厚は通常３００〜
１０００Å程度である。[0020] The thickness of the undercoat layer is usually 500 to 3000
It should be about Å. The magnetic layer composition is C by sputtering.
o-Cr, Co-Cr-X, Co-Ni-X, Co-W
A Co-based alloy magnetic film whose main component is Co represented by -X or the like can be used. Here, X is Li, Si, B, C
a, Ti, V, Cr, Ni, As, Y, Zr, Nb, M
o, Ru, Rh, Ag, Sb, Hf, Ta, W, Re,
Os, Ir, Pt, Au, La, Ce, Pr, Nd, P
One or more elements selected from the group consisting of m, Sm, and Eu are used. The thickness of the magnetic layer is usually 300~
It is about 1000 Å.
【００２１】保護膜としてはスパッタ法による炭素質膜
、ジルコニア膜等や有機シリコン膜の塗布でもよい。
潤滑層としては弗素系のパーフロロポリエーテル等の液
体潤滑膜や脂肪酸などの固体潤滑膜が用いられる。As the protective film, a carbonaceous film, a zirconia film, or an organic silicon film may be applied by sputtering. As the lubricant layer, a liquid lubricant film such as fluorine-based perfluoropolyether or a solid lubricant film such as fatty acid is used.
【００２２】なお、ガラス基板そのままにスパッタ成膜
で下引き層、磁性膜を成膜すると、ガラス基板の水分の
影響で磁気特性が低下し、保磁力が小さくなることが、
Ｊ．Ａｐｐｌ．Ｐｈｙｓ．６７（９），１，１９９０，
Ｐ．４７０１等で報告されているが、本発明の磁気記録
媒体によれば、無電解メッキ層の積層によりガラス基板
の水分の影響が防止でき、保磁力の低下が防止できる。
また、ガラス基板に導電性の無電解メッキ膜を形成する
ことにより、従来のＮｉ−Ｐ無電解メッキ層を被覆した
アルミニウム基板とほぼ同様な電気抵抗となることから
、通常のスパッタ条件での成膜だけでなく、基板に負の
バイアス電位を印加する基板バイアス法によるスパッタ
成膜が可能となり、負のバイアス電位を印加した状態で
スパッタ法により下引きＣｒ層及び／又は磁性層が成膜
でき、高保磁力を得ることが可能になる。[0022] It should be noted that if an undercoat layer and a magnetic film are formed by sputtering on the glass substrate as it is, the magnetic properties will deteriorate due to the influence of moisture on the glass substrate, and the coercive force will become smaller.
J. Appl. Phys. 67(9), 1, 1990,
P. 4701, etc., according to the magnetic recording medium of the present invention, the influence of moisture on the glass substrate can be prevented by laminating electroless plating layers, and a decrease in coercive force can be prevented. In addition, by forming a conductive electroless plating film on a glass substrate, the electrical resistance is almost the same as that of an aluminum substrate coated with a conventional Ni-P electroless plating layer, so it can be formed under normal sputtering conditions. In addition to the film, it is now possible to perform sputter deposition using a substrate bias method in which a negative bias potential is applied to the substrate, and the undercoating Cr layer and/or magnetic layer can be deposited by sputtering with a negative bias potential applied. , it becomes possible to obtain high coercive force.
【００２３】また、ガラス基板として鏡面研磨した基板
でなく、例えば化学エッチングあるいは結晶化処理等に
より基板表面を粗くした場合は、無電解メッキ層の密着
性が向上することから一段目の無電解メッキにより、１
０００Å以上の膜厚が得られる。また、これに上記した
熱処理を施すことにより密着性を更に向上させることが
できる。In addition, if the glass substrate is not a mirror-polished substrate but has a roughened substrate surface, for example by chemical etching or crystallization treatment, the adhesion of the electroless plating layer will improve, so the first step electroless plating will improve the adhesion of the electroless plating layer. Accordingly, 1
A film thickness of 000 Å or more can be obtained. Furthermore, by subjecting this to the above-described heat treatment, the adhesion can be further improved.
【００２４】[0024]
【実施例】以下に実施例により本発明をより具体的に説
明するが、本発明は、その要旨を越えない限り、以下の
実施例に限定されるものではない。[Examples] The present invention will be explained in more detail with reference to Examples below, but the present invention is not limited to the following Examples unless the gist thereof is exceeded.
【００２５】実施例１
化学強化した後、その表面を中心線平均粗さＲａ８Å、
最大高さＲｍａｘ１００Åに鏡面加工した、外径９５φ
ｍｍ、内径２５φｍｍ、板厚１．２７ｍｍのソーダライ
ムガラス基板を、中性洗剤で脱脂、イオン交換水で水洗
後、０．３ｇ／ｌのＳｎＣｌ２ 水溶液（浴温５０℃）
に１分浸漬し、水洗後、０．１ｇ／ｌのＰｄＣｌ２ 水
溶液（浴温５０℃）に１分浸漬し活性化処理を行い水洗
後、市販の無電解Ｎｉ−Ｐメッキ浴（メルテックス（株
）、エンプレートＮＩ−４８２８）にて、ｐＨ４．５、
浴温７７℃で無電解Ｎｉ−Ｐメッキ膜を３００Å形成し
た（第一段無電解メッキ）。水洗後、クリーン乾燥器で
２００℃、１時間熱処理を実施した。その後、再び中性
洗剤で脱脂を行い、イオン交換水で水洗後、再度上記無
電解Ｎｉ−Ｐメッキ浴に浸漬し、総膜厚１５００Åの無
電解Ｎｉ−Ｐメッキ膜を形成した（第二段無電解メッキ
）。水洗後、クリーン乾燥器で２００℃、１時間熱処理
を実施した。無電解メッキ処理は基板を回転しながら行
い、基板全面にメッキ皮膜が形成されるようにした。Example 1 After chemical strengthening, the surface had a center line average roughness of Ra8 Å,
Mirror-finished to maximum height Rmax 100Å, outer diameter 95φ
After degreasing a soda lime glass substrate with a diameter of 25 mm and a thickness of 1.27 mm using a neutral detergent and washing it with ion-exchanged water, a 0.3 g/l SnCl2 aqueous solution (bath temperature 50°C) was prepared.
After rinsing with water, immersing for 1 minute in a 0.1 g/l PdCl2 aqueous solution (bath temperature 50°C) for activation treatment. ), Enplate NI-4828), pH 4.5,
An electroless Ni-P plating film of 300 Å was formed at a bath temperature of 77° C. (first stage electroless plating). After washing with water, heat treatment was performed at 200° C. for 1 hour in a clean dryer. Thereafter, degreasing was performed again with a neutral detergent, and after washing with ion-exchanged water, the electroless Ni-P plating film was again immersed in the above electroless Ni-P plating bath to form an electroless Ni-P plating film with a total film thickness of 1500 Å (second stage). electroless plating). After washing with water, heat treatment was performed at 200° C. for 1 hour in a clean dryer. The electroless plating process was performed while rotating the substrate so that a plating film was formed on the entire surface of the substrate.
【００２６】この基板をＤＣマグネトロンスパッタ装置
に装入し、１×１０−６Ｔｏｒｒまで真空排気した後、
基板温度を２００℃まで昇温し、アルゴン分圧５×１０
−３Ｔｏｒｒにて、Ｃｒ下引き層を１７００Å、ＣｏＮ
ｉ３０Ｃｒ７ ａｔ％の磁性層を６００Å、カーボン保
護層を３００Åスパッタ法にて連続して成膜し磁気記録
媒体を作製した。After loading this substrate into a DC magnetron sputtering device and evacuation to 1×10 −6 Torr,
Raise the substrate temperature to 200℃, and increase the argon partial pressure to 5×10
At -3 Torr, the Cr undercoat layer was 1700 Å, CoN
A magnetic recording medium was fabricated by successively forming a magnetic layer of 600 Å of i30Cr7 at% and a carbon protective layer of 300 Å by sputtering.
【００２７】該磁気記録媒体の保磁力を試料振動式磁力
計（ＶＳＭ）にて測定したところ１１００Ｏｅであった
。得られた磁気記録媒体をクリーンな恒温恒湿槽に入れ
、８５℃、相対湿度８０％で５０４時間保持する耐候性
テストを実施したところ、何等変化が認められなかった
。The coercive force of the magnetic recording medium was measured using a vibrating sample magnetometer (VSM) and was found to be 1100 Oe. A weather resistance test was conducted in which the obtained magnetic recording medium was placed in a clean constant temperature and humidity chamber and maintained at 85° C. and 80% relative humidity for 504 hours, and no change was observed.
【００２８】また、得られた磁気記録媒体に剃刀で切り
入みを入れ当該箇所にセロテープを貼着し、はがすこと
で、メッキ膜の▲剥▼離の有無を調べるメッキ膜の密着
性テストを行なったところ、メッキ膜の▲剥▼離は見ら
れなかった。[0028] In addition, an adhesion test of the plating film was carried out to check for peeling of the plating film by making a cut in the obtained magnetic recording medium with a razor, pasting cellophane tape on the relevant part, and peeling it off. As a result, no peeling of the plating film was observed.
【００２９】比較例１
実施例１におけるのと同様な基板を、活性化処理、無電
解メッキ処理、熱処理を実施することなく脱脂、水洗後
、直ちに実施例１におけるのと同様にスパッタ装置でＣ
ｒ下引き層、磁性層及びカーボン保護層を成膜し、磁気
記録媒体を作製した。Comparative Example 1 A substrate similar to that in Example 1 was degreased without performing activation treatment, electroless plating treatment, or heat treatment, and after washing with water, it was immediately subjected to carbon dioxide using a sputtering apparatus in the same manner as in Example 1.
An undercoat layer, a magnetic layer, and a carbon protective layer were formed to produce a magnetic recording medium.
【００３０】得られた磁気記録媒体の保磁力を試料振動
式磁力計（ＶＳＭ）にて測定したところ、８００Ｏｅで
あった。また、得られた磁気記録媒体を実施例１におけ
るのと同様に耐候性テストを行なったところ、磁気記録
媒体の内外周縁全周に約幅１．５ｍｍの腐食による変色
が認められた。The coercive force of the obtained magnetic recording medium was measured using a vibrating sample magnetometer (VSM) and was found to be 800 Oe. Further, when the obtained magnetic recording medium was subjected to a weather resistance test in the same manner as in Example 1, discoloration due to corrosion with a width of about 1.5 mm was observed all around the inner and outer peripheries of the magnetic recording medium.
【００３１】比較例２
実施例１において、第二段無電解メッキにおいて、無電
解Ｎｉ−Ｐメッキの総膜厚を８００Åとした以外は、同
様にした。耐候性テストの結果、磁気記録媒体の内外周
縁全周に約幅０．５ｍｍの腐食による変色が認められた
。Comparative Example 2 The same procedure as in Example 1 was carried out except that in the second stage electroless plating, the total film thickness of the electroless Ni--P plating was 800 Å. As a result of the weather resistance test, discoloration due to corrosion with a width of about 0.5 mm was observed all around the inner and outer peripheries of the magnetic recording medium.
【００３２】比較例３
実施例１において、第一段無電解メッキ後、熱処理する
ことなく連続して第二段無電解メッキを行なった。水洗
したところ、無電解メッキ膜がガラス基板より▲剥▼離
した。Comparative Example 3 In Example 1, after the first electroless plating, the second electroless plating was performed continuously without heat treatment. When washed with water, the electroless plating film peeled off from the glass substrate.
【００３３】比較例４
実施例１において、第二段無電解メッキ後に熱処理をし
なかった以外は同様にして磁気記録媒体を作製した。得
られた磁気記録媒体について、実施例１におけるのと同
様の密着性テストを行なったところ、無電解Ｎｉ−Ｐメ
ッキ膜が▲剥▼離した。Comparative Example 4 A magnetic recording medium was produced in the same manner as in Example 1, except that no heat treatment was performed after the second electroless plating. When the obtained magnetic recording medium was subjected to the same adhesion test as in Example 1, the electroless Ni--P plating film was found to have peeled off.
【００３４】実施例２
第二段無電解メッキのメッキ浴を銅メッキ浴（奥野製薬
（株）、ＯＰＣ−７５０）とし、浴温度２３℃、ｐＨ１
２．９で無電解銅メッキ膜を形成し、総膜厚２０００Å
とし、続く熱処理を３００℃、１時間の熱処理とした以
外は実施例１と同様にした。密着性テストで▲剥▼離は
なく、また耐候性テストでも腐食が認められなかった。Example 2 The plating bath for the second stage electroless plating was a copper plating bath (Okuno Pharmaceutical Co., Ltd., OPC-750), and the bath temperature was 23°C and the pH was 1.
In step 2.9, an electroless copper plating film is formed, with a total film thickness of 2000 Å.
The procedure was the same as in Example 1 except that the subsequent heat treatment was performed at 300° C. for 1 hour. There was no peeling in the adhesion test, and no corrosion was observed in the weather resistance test.
【００３５】実施例３
Ｃｒ下引き層及び磁性層のスパッタ成膜をスパッタ装置
の基板ホルダーに−２００Ｖの負の電位を印加しながら
、行なった以外は、実施例１と同様にして磁気記録媒体
を作製した。この磁気記録媒体の保磁力を、試料振動式
磁力計ＶＳＭにて測定したところ１４００Ｏｅ（エルス
テッド）あった。密着性テストで▲剥▼離はなく、耐候
性テストでも腐食は認められなかった。Example 3 A magnetic recording medium was fabricated in the same manner as in Example 1, except that the Cr undercoat layer and magnetic layer were formed by sputtering while applying a negative potential of -200V to the substrate holder of the sputtering device. was created. The coercive force of this magnetic recording medium was measured using a vibrating sample magnetometer VSM and was found to be 1400 Oe (Oersted). There was no peeling in the adhesion test, and no corrosion was observed in the weather resistance test.
【００３６】比較例５
比較例１において、実施例３におけるのと同様にしてＣ
ｒ下引き層、磁性層及びカーボン保護層のスパッタ成膜
を行って磁気記録媒体を作製した。得られた磁気記録媒
体について実施例１におけるのと同様の保磁力の測定を
行なったところ、８００Ｏｅであった。Comparative Example 5 In Comparative Example 1, C
A magnetic recording medium was manufactured by sputtering a subbing layer, a magnetic layer, and a carbon protective layer. When the coercive force of the obtained magnetic recording medium was measured in the same manner as in Example 1, it was found to be 800 Oe.
【００３７】[0037]
【発明の効果】本発明によれば、ガラス基板からのアル
カリ分の溶出及び水分の影響を防止でき、更にガラス基
板に導電性を付与することができることから、耐候性に
優れ、かつ、磁気特性が良好な、ガラス基板を用いた磁
気記録媒体が得られる。また、アルカリ成分の溶出量の
すくない特殊組成のガラスを使用せず、安価にガラス基
板を用いた磁気記録媒体が得られる。Effects of the Invention According to the present invention, it is possible to prevent the elution of alkaline components from the glass substrate and the influence of moisture, and it is also possible to impart conductivity to the glass substrate, so it has excellent weather resistance and magnetic properties. A magnetic recording medium using a glass substrate with good properties can be obtained. Furthermore, a magnetic recording medium using a glass substrate can be obtained at low cost without using a glass having a special composition in which the amount of alkaline components eluted is small.
Claims (2)
以上の無電解メッキ層を積層したガラス基板の上に、磁
性層を設けたことを特徴とする磁気記録媒体。[Claim 1] Thickness: 1000 Å by electroless plating method
A magnetic recording medium characterized in that a magnetic layer is provided on a glass substrate on which the electroless plating layer described above is laminated.
高さＲｍａｘ１５０Å以下の表面粗さのガラス基板に、
初めに無電解メッキ法により厚さ３００Å以下の無電解
メッキ層を設けた後に１５０〜４００℃の温度で熱処理
を施し、更にその上に無電解メッキ法により無電解メッ
キ層を形成した後、１５０〜４００℃の温度で熱処理を
施すことによって総厚み１０００Å以上の無電解メッキ
層を設けたガラス基板の上に、磁性層を設けることを特
徴とする磁気記録媒体の製造法。2. A glass substrate having a surface roughness with a center line average roughness Ra of 10 Å or less and a maximum height Rmax of 150 Å or less,
First, an electroless plating layer with a thickness of 300 Å or less is provided by an electroless plating method, and then heat treatment is performed at a temperature of 150 to 400°C. A method for manufacturing a magnetic recording medium, comprising providing a magnetic layer on a glass substrate provided with an electroless plating layer having a total thickness of 1000 Å or more by heat treatment at a temperature of ~400°C.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP5703091A JPH04291018A (en) | 1991-03-20 | 1991-03-20 | Magnetic recording medium and production thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP5703091A JPH04291018A (en) | 1991-03-20 | 1991-03-20 | Magnetic recording medium and production thereof |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH04291018A true JPH04291018A (en) | 1992-10-15 |
Family
ID=13044045
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP5703091A Pending JPH04291018A (en) | 1991-03-20 | 1991-03-20 | Magnetic recording medium and production thereof |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH04291018A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6378338B1 (en) * | 1998-08-31 | 2002-04-30 | Showa Denko K.K. | Method for producing magnetic disk substrates |
| WO2012046712A1 (en) * | 2010-10-07 | 2012-04-12 | 東洋鋼鈑株式会社 | Method for producing substrate for hard disk, and substrate for hard disk |
-
1991
- 1991-03-20 JP JP5703091A patent/JPH04291018A/en active Pending
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6378338B1 (en) * | 1998-08-31 | 2002-04-30 | Showa Denko K.K. | Method for producing magnetic disk substrates |
| WO2012046712A1 (en) * | 2010-10-07 | 2012-04-12 | 東洋鋼鈑株式会社 | Method for producing substrate for hard disk, and substrate for hard disk |
| US8940419B2 (en) | 2010-10-07 | 2015-01-27 | Toyo Kohan Co., Ltd. | Method for production of hard disk substrate and hard disk substrate |
| JP5705230B2 (en) * | 2010-10-07 | 2015-04-22 | 東洋鋼鈑株式会社 | Hard disk substrate manufacturing method and hard disk substrate |
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