Claims
- 1. An optical disk substrate which comprises a polycarbonate resin containing not more than 1 ppm of each metal belonging to the IA group and the VIII group of the Periodic Table, not more than 0.3 mol percent, per polymerization repeating unit, of a terminal hydroxyl group and not more than 10 ppm of a remaining chlorinated compound solvent, said polycarbonate resin having a viscosity average molecular weight of 10,000 to 22,000.
- 2. An optical disk substrate according to claim 1, wherein the metal belonging to the group IA is sodium or potassium.
- 3. An optical disk substrate according to claim 1, wherein the metal belonging to the group VIII is iron, nickel or cobalt.
- 4. An optical information-storage medium comprising an optical recording layer formed on an optical disk substrate prepared from a polycarbonate resin containing not more than 1 ppm of each metal belonging to the IA group and the VIII group of the Periodic Table, not more than 0.3 mol percent, per polymerization repeating unit, of a terminal hydroxyl group and not more than 10 ppm of a remaining compound solvent, said polycarbonate resin having a viscosity-average molecular weight of 10,000 to 22,000.
- 5. An optical information-storage medium according to claim 4, wherein the metal belonging to the group IA is sodium or potassium.
- 6. An optical information-storage medium according to claim 4, wherein the metal belonging to the group VIII is iron, nickel or cobalt.
Priority Claims (1)
Number |
Date |
Country |
Kind |
1-14079 |
Jan 1989 |
JPX |
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Parent Case Info
This is a continuation-in-part of Ser. No. 468,862, filed Jan. 23, 1990, now abandoned.
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Number |
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Date |
Kind |
3981707 |
Araujo et al. |
Sep 1976 |
|
4199540 |
Adelmann et al. |
Apr 1980 |
|
4509163 |
Kamada et al. |
Apr 1985 |
|
4701770 |
Ito et al. |
Oct 1987 |
|
4918160 |
Kondoh et al. |
Apr 1990 |
|
Continuation in Parts (1)
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Number |
Date |
Country |
Parent |
468862 |
Jan 1990 |
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