JPH0495219A - Glass substrate for magnetic recording medium and production thereof - Google Patents
Glass substrate for magnetic recording medium and production thereofInfo
- Publication number
- JPH0495219A JPH0495219A JP21287790A JP21287790A JPH0495219A JP H0495219 A JPH0495219 A JP H0495219A JP 21287790 A JP21287790 A JP 21287790A JP 21287790 A JP21287790 A JP 21287790A JP H0495219 A JPH0495219 A JP H0495219A
- Authority
- JP
- Japan
- Prior art keywords
- glass substrate
- magnetic recording
- glass
- mold
- ruggedness
- 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
- 239000011521 glass Substances 0.000 title claims abstract description 33
- 239000000758 substrate Substances 0.000 title claims abstract description 24
- 238000004519 manufacturing process Methods 0.000 title claims description 5
- 239000000463 material Substances 0.000 claims abstract description 10
- 229910000510 noble metal Inorganic materials 0.000 claims abstract description 6
- 238000000465 moulding Methods 0.000 claims abstract description 5
- QZPSXPBJTPJTSZ-UHFFFAOYSA-N aqua regia Chemical compound Cl.O[N+]([O-])=O QZPSXPBJTPJTSZ-UHFFFAOYSA-N 0.000 claims abstract description 3
- BASFCYQUMIYNBI-UHFFFAOYSA-N platinum Chemical compound [Pt] BASFCYQUMIYNBI-UHFFFAOYSA-N 0.000 claims abstract 6
- 229910052697 platinum Inorganic materials 0.000 claims abstract 3
- 238000000034 method Methods 0.000 claims description 6
- NBIIXXVUZAFLBC-UHFFFAOYSA-N Phosphoric acid Chemical compound OP(O)(O)=O NBIIXXVUZAFLBC-UHFFFAOYSA-N 0.000 claims description 4
- 229910000147 aluminium phosphate Inorganic materials 0.000 claims description 2
- 239000010970 precious metal Substances 0.000 claims description 2
- UONOETXJSWQNOL-UHFFFAOYSA-N tungsten carbide Chemical compound [W+]#[C-] UONOETXJSWQNOL-UHFFFAOYSA-N 0.000 claims 2
- 238000010297 mechanical methods and process Methods 0.000 claims 1
- 229910001092 metal group alloy Inorganic materials 0.000 claims 1
- 239000000126 substance Substances 0.000 claims 1
- 239000005388 borosilicate glass Substances 0.000 abstract description 12
- 238000010438 heat treatment Methods 0.000 abstract description 7
- 229910052741 iridium Inorganic materials 0.000 abstract description 3
- 230000015572 biosynthetic process Effects 0.000 abstract description 2
- GKOZUEZYRPOHIO-UHFFFAOYSA-N iridium atom Chemical compound [Ir] GKOZUEZYRPOHIO-UHFFFAOYSA-N 0.000 abstract 2
- 239000011248 coating agent Substances 0.000 abstract 1
- 238000000576 coating method Methods 0.000 abstract 1
- 238000003825 pressing Methods 0.000 description 11
- HWLDNSXPUQTBOD-UHFFFAOYSA-N platinum-iridium alloy Chemical class [Ir].[Pt] HWLDNSXPUQTBOD-UHFFFAOYSA-N 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
- 230000000694 effects Effects 0.000 description 4
- 238000005498 polishing Methods 0.000 description 3
- 230000004044 response Effects 0.000 description 2
- 229910000566 Platinum-iridium alloy Inorganic materials 0.000 description 1
- 239000007864 aqueous solution Substances 0.000 description 1
- 238000003486 chemical etching Methods 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 239000013078 crystal Substances 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 229910003460 diamond Inorganic materials 0.000 description 1
- 239000010432 diamond Substances 0.000 description 1
- 238000005530 etching Methods 0.000 description 1
- 230000006870 function Effects 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 150000002739 metals Chemical class 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 238000007665 sagging Methods 0.000 description 1
- 238000004544 sputter deposition Methods 0.000 description 1
- 238000000992 sputter etching Methods 0.000 description 1
- 239000005341 toughened glass Substances 0.000 description 1
- WFKWXMTUELFFGS-UHFFFAOYSA-N tungsten Chemical compound [W] WFKWXMTUELFFGS-UHFFFAOYSA-N 0.000 description 1
- 229910052721 tungsten Inorganic materials 0.000 description 1
- 239000010937 tungsten Substances 0.000 description 1
Landscapes
- Magnetic Record Carriers (AREA)
- Manufacturing Of Magnetic Record Carriers (AREA)
Abstract
Description
【発明の詳細な説明】
産業上の利用分野
本発明は磁気記録媒体に用いる磁気記録媒体用ガラス基
板、及びその製造方法に関するもので、ＯＡ用など、情
報用メモリーの高密度化をはかるための固定磁気ディス
ク用基板等を提供するものである。DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a glass substrate for magnetic recording media used in magnetic recording media and a method for manufacturing the same. The present invention provides substrates for fixed magnetic disks, etc.
従来の技術
近年、コンピュータ利用は目ざましく、これに使われる
メモリー装置の大容量化、あるいは大容量でしかも小型
化することが積極的に進められている。固定磁気ディス
ク装置においても例外でない、たとえばコンピュータの
一つであるパソコンにおいては、小型化が盛んに行われ
てラップト。BACKGROUND OF THE INVENTION In recent years, the use of computers has been rapid, and efforts are being made to increase the capacity of memory devices used in these devices, or to make them smaller while still having a large capacity. Fixed magnetic disk drives are no exception; for example, personal computers, which are one type of computer, are being miniaturized.
プパソコン ノートパソコンなどが急進している。Personal computers and notebook computers are rapidly increasing.
これに使用されているメモリー用装置は、フロ。The memory device used for this is Flo.
ピー装置や固定磁気ディスク装置であり、両者とも小型
で大容量化の競争になっている。小型大容量化に対応し
てメモリーディスクは高密度化による大容量化が要求さ
れる。もちろんディスクの小径化は装置の小型化に応し
て行われる。There is a competition between small-sized and large-capacity devices, both of which are hard drive devices and fixed magnetic disk devices. In response to the trend toward smaller size and larger capacity, memory disks are required to have larger capacity through higher density. Of course, the diameter of the disk is reduced in response to the miniaturization of the device.
発明が解決しようとする課題
固定磁気ディスクにおいては、その使用基板は、従来か
らアルミディスクが使用されてきているが、これにより
高密度記録をしていくためには、■ ヘッドとディスク
間の空隙をより狭くしていく必要がある。Problems to be Solved by the Invention Conventionally, aluminum disks have been used as substrates for fixed magnetic disks, but in order to achieve high-density recording, it is necessary to reduce the gap between the head and the disk. need to be made narrower.
■ そのために、ヘッドの構造問題もあるが、ディスク
の表面をより平滑にしていく必要がある。■ For this reason, there is a problem with the structure of the head, but it is necessary to make the surface of the disk smoother.
アルミディスクの表面をより平滑にしていく努力もなさ
れているが、表面形成時に起こる金属特有のだれなどに
よりなかなか困難である。Efforts have been made to make the surface of aluminum disks smoother, but this is difficult due to the inherent sagging of metals that occurs during surface formation.
最近、固定磁気ディスク、特に小型のディスク基板用と
してガラスを用いる検討が進められかけている。ガラス
としては、無定形構造、あるいは結晶化構造のガラスが
対象になっている。こわらを用いてディスク化するには
、基本的に従来のアルミディスクと同様表面を研磨する
ことにより平滑化している。また、表面の凹凸化は、■
研磨により平滑化をしたガラスを強化ガラス化する。Recently, studies are underway to use glass for fixed magnetic disks, especially small disk substrates. The target glass is glass with an amorphous structure or a crystallized structure. To make a disk using Kowara, the surface is basically polished to make it smooth, just like conventional aluminum disks. In addition, the unevenness of the surface is
Glass that has been smoothed by polishing is made into toughened glass.
■ 結晶化ガラスを用い結晶粒のサイズの凹凸を設ける
。■ Use crystallized glass to create irregularities of the size of crystal grains.
このような方法では、アルミディスクと同様表面の研磨
をする工程が必要であるため工数が増しコスト高となる
。表面の凹凸も、その大きさ、並べ方のコントロールは
できないなどの問題がある。This method requires a step of polishing the surface as with aluminum disks, which increases the number of man-hours and costs. There are also problems with the unevenness of the surface, such as the size and arrangement of the unevenness cannot be controlled.
課題を解決するための手段
上記課題を解決する手段として、
■ 磁気ディスクが小径化する有利さから基板にガラス
材料を用いる。Means for Solving the Problems As a means for solving the above problems, (1) Use a glass material for the substrate because it has the advantage of reducing the diameter of the magnetic disk.
■ ガラス基板の表面平滑性の高精度化は、表面平滑性
が高精度に形成された超硬合金を母材とし、その上に耐
熱性があり高硬度な貴金属層を被覆してなる加圧金型で
もって高温中にて加圧成型して達成する。■ High-precision surface smoothness of glass substrates is achieved by pressurization, which uses a cemented carbide base material with a highly precisely formed surface smoothness, and coats it with a heat-resistant and hard noble metal layer. Achieved by pressure molding in a mold at high temperature.
■ 磁気ディスクの表面へのヘッドの吸着を避けるため
従来と同様のテクスチャーを基板表面に設けるには、上
記金型に凹凸を設け、加圧成型してガラス基板にその凹
凸を転写する。(2) To provide a similar texture to the substrate surface as in the past in order to avoid adhesion of the head to the surface of the magnetic disk, the above-mentioned mold is provided with unevenness, and the unevenness is transferred to the glass substrate by pressure molding.
■ なお、■と■は同時に行える。■ Note that ■ and ■ can be performed at the same time.
作用
本発明は、耐熱性、超硬合金母材あるいはその上に設け
た高硬度貴金属層でしかもその表面に、任意のテクスチ
ャー用凹凸をあらかしめ、機械的加工、化学的エツチン
グ、あるいはスパッタエツチングなどによって形成して
おき、この金型を用いてガラス基板を加熱加圧成型する
ことによって容易にガラスの表面は平滑に、しかも任意
のテクスチャーが高精度にでき、安定でしかも大幅なコ
スト低下ができる。Function The present invention is a heat-resistant cemented carbide base material or a high-hardness precious metal layer provided thereon, and furthermore, the surface thereof is provided with irregularities for texture, and is processed by mechanical processing, chemical etching, sputter etching, etc. By using this mold to mold the glass substrate under heat and pressure, the surface of the glass can be easily smoothed and any desired texture can be created with high precision, making it stable and significantly reducing costs. .
実施例 以下に本発明の一実施例を説明する。Example An embodiment of the present invention will be described below.
実施例Ｊ
直径７０−４高さ２５閣のタングステンカーハイ） （
ＷＣ）の緻密な焼結体の押し型１．２を用意し、一方の
底面を〜２０人の平滑度に鏡面研磨した後、０．５モル
％の燐酸水溶液を用いて鏡面研磨した面をエッチングし
た。エッチングは鏡面が〜５０人の凹凸７になる程度に
した。次に、高周波スパッタ装置を用いて厚み３μｍの
白金−イリジュウム合金膜４を凹凸７を形成した面上に
成膜した。Example J Tungsten car high with a diameter of 70-4 and a height of 25 mm) (
Prepare a press mold 1.2 of a dense sintered body of WC), mirror-polish one bottom surface to a smoothness of ~20 people, and then polish the mirror-polished surface using a 0.5 mol% phosphoric acid aqueous solution. Etched. The etching was done so that the mirror surface had ~50 bumps and 7 bumps. Next, a platinum-iridium alloy film 4 having a thickness of 3 μm was formed on the surface on which the unevenness 7 was formed using a high frequency sputtering device.
上と同様な方法で作成した白金−イリジュウム膜／ＷＣ
の押し型を２個準備した。Platinum-iridium film/WC prepared in the same manner as above
Two pressing molds were prepared.
この押し型１，２を第１図に示す加熱加圧機にセットし
く凹凸形成面を向かい合わせてセットする）、押し型加
熱ヒータ５，６で６００°Ｃに予備加熱しておいた。さ
らに、あらかしめ外径６３ｍ内径２５ｍ、厚み１．０１
ｍａ＋の寸法に形成しておいたホウ珪酸ガラス板３を押
し型１．２の間にセットした。次に、押し型１．２をヒ
ータ５．６で７００°Ｃ迄昇温し、加圧力２ｋｇ−ｃｔ
ａ’の圧力で加圧成型した。このとき押し型１．２の対
向間隔は、平行で１．００閣になるまで押し２分間保持
した。The press molds 1 and 2 were set in the heating and pressing machine shown in FIG. 1 with the uneven surfaces facing each other), and were preheated to 600° C. with the press mold heaters 5 and 6. In addition, the outer diameter is 63m, the inner diameter is 25m, and the thickness is 1.01.
A borosilicate glass plate 3, which had been formed to a dimension of ma+, was set between the press molds 1.2. Next, the temperature of the press mold 1.2 was raised to 700°C using a heater 5.6, and a pressing force of 2 kg-ct was applied.
Pressure molding was performed at a pressure of a'. At this time, the pressing molds 1.2 were pressed and held for 2 minutes until the opposing distance was 1.00 cm in parallel.
その後押し型が４５０°Ｃになるまでホウ珪酸ガラス板
３を押し型１．２ではさんだままの状態で冷却し、後取
り出した。Thereafter, the borosilicate glass plate 3 was cooled while being sandwiched between the press molds 1.2 until the temperature of the press molds reached 450° C., and then taken out.
実施例２
実施例１と基本的には同様の方法であるが、凹凸７の形
成は白金−イリジュウム膜４を形成した後、王水にて白
金−イリジュウム膜の表面に形成し、凹凸の程度は〜５
０人とした。実施例１と同様な方法で実施例１に用いた
はう珪酸ガラス板３を加熱加圧し、取り出した。Example 2 The method is basically the same as in Example 1, but the unevenness 7 is formed by forming the platinum-iridium film 4 on the surface of the platinum-iridium film using aqua regia, and determining the degree of the unevenness. Ha~5
There were 0 people. The borosilicate glass plate 3 used in Example 1 was heated and pressed in the same manner as in Example 1, and then taken out.
実施例３
実施例１と同様の一対のＷＣより成る押し型１２の各底
面を実施例１程度に鏡面研磨した後、粒径が１μｍのダ
イアモンドペーストを用いて、上記ＷＣの押し型１，２
の軸を中心にして回転させ鏡面研磨した面に〜５０人の
凹凸を、軸を中心にして半径方向に同心円状に形成した
。その上に、白金−イリジュウム膜４を実施例１と同し
方法で形成した。Example 3 After mirror-polishing the bottom surface of each of the pressing molds 12 made of a pair of WC similar to those in Example 1 to the same level as in Example 1, the WC pressing molds 1 and 2 were polished using diamond paste with a particle size of 1 μm.
The mirror-polished surface was rotated around the axis, and ~50 concavities and convexities were formed concentrically in the radial direction with the axis as the center. Thereon, a platinum-iridium film 4 was formed in the same manner as in Example 1.
このようにして作成した一対の押し型を用いて、実施例
１と同様にホウ珪酸ガラス板３を加熱加圧し、取り出し
た。Using a pair of press molds thus prepared, the borosilicate glass plate 3 was heated and pressed in the same manner as in Example 1, and then taken out.
実施例１の効果
■ 加熱加圧したホウ珪酸ガラス基板の平滑性は、押し
型の押し面とほとんど差がなく〜２０人程度であった。Effects of Example 1 ■ The smoothness of the heated and pressurized borosilicate glass substrate was about 20 to 20 people, with almost no difference from the pressing surface of the pressing mold.
■ 押し型の押し面に形成した凹凸〜５０人はホウ珪酸
ガラス板表面に〜５０人の凹凸としてほとんど同じ形状
で転写されていた。■ The irregularities formed on the pressing surface of the mold were transferred onto the surface of the borosilicate glass plate in almost the same shape as the irregularities formed on the surface of the borosilicate glass plate.
実施例２の効果
実施例１と同様、〜５０人の凹凸がホウ珪酸ガラス基板
表面に形成されており良好な結果が得られた。Effects of Example 2 Similar to Example 1, ~50 irregularities were formed on the surface of the borosilicate glass substrate, and good results were obtained.
実施例３の効果
押し型の押し面に形成された同心円状の〜５０人の凹凸
が加熱加圧されたホウ珪酸ガラス板に同じ凹凸で同心円
状に転写されていた。The concentric circular irregularities formed on the pressing surface of the effect stamping die of Example 3 were transferred concentrically with the same irregularities to the heated and pressurized borosilicate glass plate.
発明の効果
このように本発明の表面にテクスチャーとしての凹凸は
、本発明の金型を用いた加熱加圧方法を用いれば非常に
精度よく良好に得られる。Effects of the Invention As described above, unevenness as a texture on the surface of the present invention can be obtained with excellent accuracy and good accuracy by using the heating and pressing method using the mold of the present invention.
なお本発明においては、ホウ珪酸ガラスについてのみ実
施例を示したが、Ｐｂ系ガラス、結晶化ガラスにおいて
も本発明は使用でき、しかも有効である。ただ結晶化ガ
ラスの場合は加熱加圧する前の状態をガラスが結晶化し
ない状態に保持しておくことが必要である。In the present invention, examples have been shown only for borosilicate glass, but the present invention can also be used and is effective for Pb-based glass and crystallized glass. However, in the case of crystallized glass, it is necessary to maintain the state in which the glass does not crystallize before heating and pressurizing.
第１図は本発明のガラス磁気ディスク基板を作成する装
置の一実施例図で、ガラス基板を加圧加熱する加圧加熱
装置、ガラス板の表面を平滑にしかつテクスチャーを形
成する押し型より構成されている。
１．２・・・・・・押し型（ＷＣ）、３・・・・・・ホ
ウ珪酸ガラス板、４・・・・・・白金−イリジュウム膜
、５，６・・・・・・押し型加熱用ヒータ、７・・・・
・・押し型の底面に設けた凹凸。
代理人の氏名 弁理士 粟野重孝 ほか１名１、ｆ−一
一↑甲し型（Ｗ（）FIG. 1 is a diagram showing an embodiment of the apparatus for producing a glass magnetic disk substrate according to the present invention, which is composed of a pressure heating device that presses and heats the glass substrate, and a press die that smoothes and textures the surface of the glass plate. has been done. 1.2...Press mold (WC), 3...Borosilicate glass plate, 4...Platinum-iridium film, 5,6...Press mold Heating heater, 7...
...Irregularities provided on the bottom of the press mold. Name of agent: Patent attorney Shigetaka Awano and 1 other person 1, f-11↑Kashi type (W ()
Claims (6)
層を被覆し、さらにその表面に凹凸を設けた金型にてガ
ラスを高温中で加圧成形して平滑化したガラス表面にテ
クスチャーを設けたことを特徴とする磁気記録媒体用ガ
ラス基板。(1) A glass surface made of cemented carbide as a base material, whose surface is coated with a highly hard precious metal layer, and which is then pressure-formed at high temperature using a mold with irregularities on the surface. A glass substrate for a magnetic recording medium, characterized in that a texture is provided on the glass substrate.
用いて加圧成形してなることを特徴とする請求項（１）
記載の磁気記録媒体用ガラス基板。(2) Claim (1) characterized in that the product is formed by pressure molding using a mold using tungsten carbide as the base material.
The described glass substrate for magnetic recording media.
する請求項（１）記載の磁気記録媒体用ガラス基板。(3) The glass substrate for a magnetic recording medium according to claim (1), wherein the noble metal layer is made of a platinum-based metal alloy.
水溶液にて粒界エッチを行い凹凸を形成した金型にて加
圧成形したことを特徴とする磁気記録媒体用ガラス基板
の製造方法。(4) A method for manufacturing a glass substrate for a magnetic recording medium, characterized in that the surface of a tungsten carbide base material is pressure-molded using a mold in which grain boundaries are etched with an aqueous phosphoric acid solution to form irregularities.
を行い凹凸を形成した金型にて加圧成形したことを特徴
とする請求項（４）記載の磁気記録媒体用ガラス基板の
製造方法。(5) The glass substrate for magnetic recording media according to claim (4), characterized in that the noble metal surface of the mold is pressure-molded using a mold whose surface has been etched with aqua regia to form irregularities. Production method.
法あるいは化学的手法にて凹凸を形成した金型にて加圧
成形したことを特徴とする請求項（４）記載の磁気記録
媒体用ガラス基板の製造方法。(6) The magnetic recording according to claim (4), characterized in that the magnetic recording material is pressure-molded using a mold in which concentric irregularities are formed on the surfaces of the base material and the noble metal layer by a mechanical method or a chemical method. A method for manufacturing a glass substrate for media.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP21287790A JPH0495219A (en) | 1990-08-10 | 1990-08-10 | Glass substrate for magnetic recording medium and production thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP21287790A JPH0495219A (en) | 1990-08-10 | 1990-08-10 | Glass substrate for magnetic recording medium and production thereof |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH0495219A true JPH0495219A (en) | 1992-03-27 |
Family
ID=16629742
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP21287790A Pending JPH0495219A (en) | 1990-08-10 | 1990-08-10 | Glass substrate for magnetic recording medium and production thereof |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0495219A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6151917A (en) * | 1997-08-07 | 2000-11-28 | Matsushita Electric Industrial Co., Ltd. | Press-molding die for magnetic-disk glass substrate |
-
1990
- 1990-08-10 JP JP21287790A patent/JPH0495219A/en active Pending
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6151917A (en) * | 1997-08-07 | 2000-11-28 | Matsushita Electric Industrial Co., Ltd. | Press-molding die for magnetic-disk glass substrate |
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