Patent ID: 8153835

Claim:
A fullerene derivative represented by the following formula (1): wherein: R 1 is a substituted or unsubstituted organic group or a hydrogen atom; and each R 2 is independently a group represented by the following formula (3) or (4), wherein: W 1 is C 2 -C 12 alkynylene, wherein any —CH 2 — in the alkynylene is optionally substituted with —O—, —S—, —C(═O)O—, or —O—C(═O)—; W 2 is a single bond, C 1 -C 11 alkylene, C 2 -C 12 alkenylene, or C 2 -C 12 alkynylene, wherein any —CH 2 — in the alkylene, alkenylene or alkynylene is optionally substituted with —O—, —S—, —C(═O)O—, or —O—C(═O)—; R 21 to R 25 are each independently a substituted or unsubstituted C 1 -C 20 alkyl group, a substituted or unsubstituted C 2 -C 15 alkenyl group, or a substituted or unsubstituted C 2 -C 15 alkynyl group; and R 26 is a substituted or unsubstituted C 4 -C 20 alkyl group, a substituted or unsubstituted C 4 -C 15 alkenyl group, or a substituted or unsubstituted C 4 -C 15 alkynyl group, wherein the fullerene derivative in the crystal state or the liquid crystal state has a layer structure.