Accelerated Aging Studies for Polycarbonate Optical Disk Substrates

Abstract

Accelerated aging studies have been reported2,3 on a write-once read-many optical data storage medium, based on proprietary naphthalocyanine recording layer materials. In the course of that work, it was observed that the polycarbonate substrates become brittle after exposure to 80°C and 80% relative humidity. Earlier, Bair et al.4 reported that, upon exposure to 85°C and 96% relative humidity for 720 hr, polycarbonate hydrolyzed to give brown surface crystals of bisphenol A monomer. Such hydrolysis for polycarbonate substrates could lead to catastrophic failure for optical disks, regardless of the stability for the recording layer. In this paper, accelerated aging studies for polycarbonate optical disk substrates are reported. The purpose of this study was to ascertain whether polycarbonate optical disk substrates degrade under conditions used to study the accelerated aging of optical disks.