Optical disk substrate and molding material therefor
AssigneeTeijin Chemicals, Ltd.
InventorsMakoto Ishida, Tsukasa Saito
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Abstract
An optical disk substrate formed of an aromatic polycarbonate resin obtained by a reaction between an aromatic dihydroxy compound and a carbonate diester and in which the content of undissolved substances that emit light by irradiation with light having a wavelength of 380 nm and have a size of 30 μm or greater is 100 pieces or less per kg of said resin, and a molding material therefor. According to the present invention, there can be provided an optical disk substrate in which the number of white spots that occur in the passage of a long period of time is very small and the reliability of writing and reading of information is highly stable.
Claims19
An optical disk substrate formed of an aromatic polycarbonate resin obtained by a reaction between an aromatic dihydroxy compound and a carbonate diester and in which the content of undissolved substances that emit light by irradiation with light having a wavelength of 380 nm and have a size of 30 μm or greater is 100 pieces or less per kg of said resin.
An optical disk substrate formed of a resin, wherein;
- (A) the resin is an aromatic polycarbonate resin obtained by a reaction between an aromatic dihydroxy compound and a carbonate diester,
- (B) the resin has 100 pieces or less per kg of said resin of undissolved substances that emit light by irradiation with light having a wavelength of 380 nm and have size of 30 μm or greater,
- (C) the resin has a relative fluorescence intensity, based on a reference substance, of 4×10−3 or less at 465 nm when the resin is measured for fluorescence spectrum, and
- (D) the resin has a residual catalyst activity index of 2% or less.
A molding material for optical use, which is an aromatic polycarbonate resin obtained by a reaction between an aromatic dihydroxy compound and a carbonate diester, and which is also a resin in which the content of undissolved substances that emit light by irradiation with light having a wavelength of 380 nm and have a size of 30 μm or greater is 100 pieces or less per kg of said resin.
An optical disk formed from a molding material comprising an aromatic polycarbonate resin obtained by a reaction between an aromatic dihydroxy compound and a carbonate diester, wherein the resin has a content of undissolved substances that emit light by irradiation with light having a wavelength of 380 nm and have a size of 30 μm or greater which is 100 pieces or less per kg of said resin.
Dependencies are inferred from the claim text.