Organic substances that conduct electricity, such as conductive polymers, are important key materials for organic EL such as tablets and smartphones and next-generation smart devices (sensors and terminals that can be attached to the body).Orientation of conductive polymers (arranged in a certain direction) is extremely important for improving the performance of these devices, and contributes to sensor response speed, screen brightness, and power saving by several hundred times.

　This time, the research group simply drops a substrate (glass plate, etc.) with a cotton cloth, then drops and dries a solution of plastic molecules (conductive polymer) that conducts electricity, and an alignment film (conductive polymer) is lined up. We have developed a very simple method to obtain (thickness 30 nanometers).

　Since this method is performed in normal temperature / air instead of the conventional high temperature / vacuum environment, not only can organic substances that are easily decomposed at high temperature be used as materials, but also equipment costs can be reduced, and high-efficiency mass production can be expected.Also, when soaked in water, the alignment film can be easily peeled off from the substrate, so it can be moved to any place and used.Furthermore, when electricity was passed through the alignment film, it emitted EL and showed polarization.

　In this experiment, in addition to the conductive polymers (P3HT and MEH-PPV) often used in organic solar cells and organic EL, alignment films were obtained for multiple molecules and substrates.In the future, he plans to develop research on the fabrication and structural analysis of alignment films for more conductive polymers and substrates.

Paper information:[Scientific Reports] Uniaxial orientation of P3HT film prepared by soft friction transfer method