| abstract |
NEW MATERIAL: An amido-contg. azulene squaric acid dye represented by formula I (wherein L is a 1-12C alkylene; R 1 and R 2 are each H, a 1-20C alky1, a 5-7C cycloalkyl, phenyl, etc.; and R 3 , R 4 , R 5 , and R 6 are each H, a halogen, a 1-12C alkoxy, phenyl, etc.). n USE: An optical recording medium. An azulene squaric acid dye represented by formula I exhibits excellent optical data. Moreover, the dye has a very stable pure color layer, does not undergo recrystallization, and hence dispenses with a polymer binder. A remarkable feature of the dye is that a structural resin substrate can be spin-coated with it directly (without a protective layer). n PROCESS: The objective compd. is obtd. by reacting an azulene deriv. represented by formula II with squaric acid represented by formula III. n COPYRIGHT: (C)1991,JPO |