| abstract |
A novel indolium compound of general formula (I) and an optical recording material containing the indolium compound. n nIn formula (I), ring A is a benzene ring, etc.; ring B is a 5- or 6-membered heterocyclic ring; R 1 is a group of general formula (II), etc.; R 2 is an organic group having 1 to 30 carbon atoms, etc.; Y 1 is an alkyl group having 1 to 10 carbon atoms, etc.; Z 1 and Z 2 are each, e.g., an alkyl group having 1 to 8 carbon atoms optionally substituted with a halogen atom and optionally interrupted by —O—, etc.; a is an integer of 0 to 6; b is an integer of 0 to 5; An q− is a q-valent anion; q is 1 or 2; and p is a number necessary to neutralize an electric charge. |