TTF-carboxylic acid 2 exhibits gelling ability for hexane and cyclohexane to form an orange fibrous material and shows solvatochromism both in solution and in the fiber formation to produce a reddish-purple fibrous material from acetonitrile. Moreover, the corresponding ester 1 forms yellow fibers from acetonitrile. However, the tetrabutylammonium salt 3 produces fine microcrystals without gel or fiber formation.