REWRITING TYPE PHOTOCHROMIC OPTICAL DISK

摘要

PURPOSE: To enhance the stability and heat stability of repeated recording and erasure in the title optical disk having a photochromic recording layer composed of an diaryl ethane derivative reacting with a specific wavelength to be changed in its state, by using a compound represented by a specific chemical formula as the derivative. ;CONSTITUTION: A rewriting type photochromic optical disk is obtained by forming a reflecting layer 3 composed of aluminum on the photochromic recording layer 2 provided to a transparent substrate 1 and protecting the same by a protecting layer 4. Guide grooves for tracking and pre-pits 5 for controlling the writing and reading of data are formed on the main surface of the substrate 1. The photochromic recording layer 2 is formed from a diaryl ethane derivative changing from a first state having a first absorption wavelength band to a second state having a second absorption wavelength band at the time of the reaction with light having a first wavelength and changing from the second state to the first state at the time of the reaction with light having a second wavelength. This derivative becomes compounds represented by respective formulae I, II in the first and second states.;COPYRIGHT: (C)1993,JPO&Japio