Title:
OPTICAL DISK SUBSTRATE AND OPTICAL DISK
Document Type and Number:
Japanese Patent JP3768903
Kind Code:
B2
Abstract:
PROBLEM TO BE SOLVED: To provide an optical disk substrate hardly suffering from warpage and wobbling which is formed of a specific polycarbonate resin excellent in low water absorption, flexural modulus of elasticity, flowability and heat resistance and having a small photoelastic constant.
SOLUTION: The optical disk substrate is formed of an aromatic polycarbonate resin which comprises an aromatic dihydroxy component, at least 20 mole% of the total amount thereof being 9,9-bis(3-methyl-4-hydroxyphenyl)fluorene, further comprises 0.01-0.2 mole%, based on the total amount of the aromatic dihydroxy component, of a trifunctional or higher-functional phenolic compound as a copolymerization component and satisfies (A) a glass transition temperature of 120-180°C, (B) a water absorption of at most 0.1 wt.% after immersion in water at 23°C for 24 hours and (C) a flexural modulus of elasticity of 2,800-4,000 MPa.
Inventors:
Masahito Ando
Manabu Matsui
Manabu Matsui
Application Number:
JP2002058820A
Publication Date:
April 19, 2006
Filing Date:
March 05, 2002
Export Citation:
Assignee:
Teijin Chemicals Ltd.
International Classes:
C08G64/06; G11B7/2534; (IPC1-7): C08G64/06; G11B7/24
Domestic Patent References:
| JP2001192447A |
Attorney, Agent or Firm:
Masataka Oshima