Optical data carriers and method for producing the same

US6855390B1 · kind B1 · utility

Assignees

• BAYER HEALTHCARE LLC · DE
• Bayer Antwerpen N.V. · BE

Inventors

• Wilfried Haese · Rheydt, DE
• Friedrich-Karl Bruder · Krefeld, DE
• Thomas Bieringer · Odenthal, DE
• Steffen Kuhling · Meerbusch, DE
• Franky Bruynseels · Sint-Gillis-Waas, BE
• Dirk Van Meirvenne · Bang Phra, TH
• René de Cleyn · Brasschaat, BE

Key dates

• Filing date: Oct 23, 2000
• Grant date: Feb 15, 2005
• Expiry date: Oct 23, 2020

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10T428/21
• WIPO field: Macromolecular chemistry, polymers
• WIPO sector: Chemistry

Abstract

A process for the preparation of optical data carriers made of a particualr polycarbonate is disclosed. The polycarbonate is prepared by the phase boundary process that entails reacting at least one dihydroxydiarylalkane in the form of its alkali metal salts with phosgene in the heterogeneous phase in the presence of sodium hydroxide solution and an organic solvent. The process is characterized in that the feedstock have but low content of Fe, Cr, Ni, Zn, Ca, Mg, Al metals or homologues thereof, and in that the organic solvent is separated off, and in that the polycarbonate which is obtained is worked up. The resulting polycarbonate is particularly useful in producing optical data carriers.