Thermochromism of poly(substituted thiophene) with urethane bond and its application to reversible thermal recording

We synthesized a novel poly( substituted thiophene) which has a long alkyl group with a urethane bond at the 3-position of the thiophene ring. The UV-visible absorption and X-ray diffraction methods reveal thermochromic properties of the polymers, which show the possibility of applying them to reversible thermal recording. The color change of the polymer from brownish-red to yellow was fixed by heating and quenching to room temperature (heat-quenching method). The fixed yellow color returned to the initial color of brownish-red after annealing at 100 degrees C (annealing method).