PURPOSE: To eliminate the danger of explosiveness while obtaining excellent recording capacity and stability by using a cyanine compd. represented by specific formula in an optical data-recording medium of a heat mode having an org. coloring matter membrane and generating a state change by high density energy beam to perform the reproduction of recording.
CONSTITUTION: A cyanine compd. represented by formula is synthesized by dissolving a salt of a cyanine compd. in a proper solvent and adding an aq. HPF6 soln. to the resulting soln. to sediment a PF6- salt of the cyanine compd. or reacting KPF6 or a PF6- salt of benzyltrimethylammonium hexafluorophosphate and the salt of the cyanine compd. in a proper solvent to sediment the PF6- salt of the cyanine compd. This cyanine compd., a quencher and, if necessary, a binder are dissolved in a mixed solvent and the resulting soln. is applied to a base material to be dried to obtain an optical data recording medium.
ADACHI KEIICHI
YABE MASAO
