JPS6462819A - Production of magnetic disk substrate - Google Patents
Production of magnetic disk substrateInfo
- Publication number
- JPS6462819A JPS6462819A JP22002187A JP22002187A JPS6462819A JP S6462819 A JPS6462819 A JP S6462819A JP 22002187 A JP22002187 A JP 22002187A JP 22002187 A JP22002187 A JP 22002187A JP S6462819 A JPS6462819 A JP S6462819A
- Authority
- JP
- Japan
- Prior art keywords
- disks
- temp
- flatness
- synthetic resin
- doughnut
- 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
Landscapes
- Magnetic Record Carriers (AREA)
- Manufacturing Of Magnetic Record Carriers (AREA)
- Compositions Of Macromolecular Compounds (AREA)
Abstract
PURPOSE:To provide excellent smoothness and flatness simultaneously to magnetic disks and to substantially eliminate surface defects so that the flatness is hardly changed in spite of a heating treatment by using metallic molds for molding to mold doughnut-shaped disks made of a synthetic resin, then holding plural sheets of the disks perpendicularly, increasing the distance between the centers of the disks to the size larger than the diameter of the disks and annealing the disks. CONSTITUTION:The doughnut-shaped disks 1 made of the synthetic resin are molded by using the metallic molds for molding. Plural sheets of the resultant disks 1 are perpendicularly held and are disposed at the distance L between the centers of the disks 1 larger than the diameter D of the disks, then the disks are annealed. Synthetic resins such as polyether imide, polyether sulfone, polyphenylene sulfide, polyarylate, polyether ether ketone, and polycarbonate having excellent heat resistance are adequately used for the synthetic resin. The metallic mold temp. is adequately the temp. lower by 60 deg.C than the glass transition temp. of the synthetic resin to be used or above and the temp. lower by 20 deg.C than the glass transition temp. or below. The excellent smoothness and flatness are thereby provided to the disks and the surface defects thereof are substantially eliminated. The flatness of the disks is hardly changed in spite of the heating treatment.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP22002187A JPS6462819A (en) | 1987-09-02 | 1987-09-02 | Production of magnetic disk substrate |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP22002187A JPS6462819A (en) | 1987-09-02 | 1987-09-02 | Production of magnetic disk substrate |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPS6462819A true JPS6462819A (en) | 1989-03-09 |
Family
ID=16744690
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP22002187A Pending JPS6462819A (en) | 1987-09-02 | 1987-09-02 | Production of magnetic disk substrate |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS6462819A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0316020A (en) * | 1989-03-29 | 1991-01-24 | Fuji Photo Film Co Ltd | Production of sheet like recording medium |
-
1987
- 1987-09-02 JP JP22002187A patent/JPS6462819A/en active Pending
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0316020A (en) * | 1989-03-29 | 1991-01-24 | Fuji Photo Film Co Ltd | Production of sheet like recording medium |
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