Patent ID: 8197923

Claim:
An optical recording medium comprising a substrate and an optical recording layer on the substrate, the optical recording layer being formed of an optical recording material comprising at least one heterocyclic compound represented by general formula (I): wherein, Z 1 represents an oxygen atom, a sulfur atom, a selenium atom, —CR 5 R 6 —, —NH—, or —NR; R 5 and R 6 each independently represent an alkyl group having 1 to 8 carbon atoms, an aryl group having 6 to 20 carbon atoms, an aralkyl group having 7 to 20 carbon atoms, or a substituent represented by general formula (II), or R 5 and R 6 are taken together to form a ring; wherein R 7 , R 8 , R 9 , and R 10 each independently represent a hydrogen atom, a halogen atom, or an alkyl group having 1 to 4 carbon atoms, a methylene moiety in the alkyl group having 1 to 4 carbon atoms may be replaced with —O—or —CO—, and R 7 and R 8 may be taken together to form a ring; R represents a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, an aryl group having 6 to 20 carbon atoms, or an aralkyl group having 7 to 20 carbon atoms; R 1 and R 2 each independently represent a hydrogen atom, a halogen atom, a cyano group, an alkyl group having 1 to 8 carbon atoms, or an aralkyl group having 7 to 20 carbon atoms; R 3 and R 4 each independently represent an alkyl group having 1 to 8 carbon atoms or an aryl group having 6 to 20 carbon atoms, or R 3 and R 4 are taken together to form a heterocyclic ring having no multiple bond; Y 1 represents a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, an aryl group having 6 to 20 carbon atoms, or an aralkyl group having 7 to 20 carbon atoms, wherein the alkyl group having 1 to 8 carbon atoms as represented by R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , or R, the aryl group having 6 to 20 carbon atoms as represented by R 3 , R 4 , R 5 , R 6 , R, or Y 1 , and the aralkyl group having 7 to 20 carbon atoms as represented by R 1 , R 2 , R 5 , R 6 , R, or Y 1 may have a substituent, and a methylene moiety of the alkyl group having 1 to 8 carbon atoms as represented by R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , or R may be replaced with —O—or —CH═CH—; An q− represents a q-valent anion, wherein q represents 1 or 2, p represents a number necessary to neutralize the electric charge of the heterocyclic compound, and n represents a number of 1 to 4.