NEW MATERIAL:Complex salts expressed by formula I [R is 1-6C alkyl; m is a positive number (0.5-1.5) corresponding to the number of mol of 7,7,8,8- tetracyanoquinodimethane contained in 1mol complex salts].

EXAMPLE: N-Methyl-2-thiophenealdehyde 1,1-dimethylhydrazone.quaternary ammonium.7,7,8,8-tetracyanoquinodimethane complex salt.

USE: An organic semiconductor useful as an electrically conductive material in the field of electronic devices or materials, etc.

PREPARATION: N-Substituted-2-thiophenealdehyde 1,1- dimethylhydrazone.quaternary ammonium salts expressed by formula II (X is halogen) are reacted with 7,7,8,8-tetracyanoquinodimethane expressed by formula III in an inert solvent, such as acetonitrile, at the boiling point of the above-mentioned solvent under ordinary pressure to afford the complex salts expressed by formula I.