Abstract: When ?EST of at least one of a donor compound and an acceptor compound to form an exciplex is 0.35 eV or less, the driving lifetime of an exciplex light-emitting device can be improved.

Abstract: A resist underlayer film-forming composition that exhibits a high etching resistance, a favorable dry etching rate ratio and optical constant, and can form a film exhibiting a good coatability even to a so-called uneven substrate, providing a small difference in film thickness after embedding, and having planarity and a superior hardness; a resist underlayer film formed from the resist underlayer film-forming composition; and a method of producing a semiconductor device.

Abstract: A straddled vehicle includes a vehicle body frame, a bracket, and a footrest. The bracket is attached to the vehicle body frame. The footrest is movably supported by the bracket to be in one of an expanded position and a folded position. In the expanded position, the footrest extends outward from the vehicle body frame in the left-right direction. In the folded position, the footrest is rotated upward from the expanded position. The bracket includes a base portion and an extending portion. The base portion is disposed along the vehicle body frame. The extending portion extends outward from the base portion in the left-right direction. The footrest includes a contact portion that contacts the bracket at the folded position. The extending portion includes a receiving surface that contacts the contact portion, and that is located at an outer edge in the left-right direction of the extending portion.

Abstract: The present disclosure relates to compounds of Formula (I) as useful materials for OLED's. R is hydrogen or phenyl substituted with at least one alkyl; and D, D? and D? independently have diarylamino or indolyl moiety.