3D Micropatterning With Thermochromic Polymer Microfiber

Abstract Although 3D micropattern has received considerable attention due to their remarkable usability, the introduction of specific functions, such as “chromism”, is still a challenge mainly due to the lack of adequate functional materials that can be introduced into 3D printing system. In this study, 3D micropatterns with temperature‐responsive properties are created by elaborately aligned thermochromic polymer microfibers using charge reversal electro‐jet writing (CREW) method with a 3D printer. A reversible color change in response to the temperature change is exhibited in the micropattern, displaying various chromic colors, such as red, blue, and black, at their own thermochromic temperatures. Multiple‐color phases can be sequentially expressed in a single structure by incorporating pigments of different colors with distinguishable color shift ranges. Various patterning methods are proposed for manufacturing diverse patterns and demonstrating applications using combinations of color. In addition to directly increasing temperature, the thermochromic process of micropatterns can be induced by heat generated from external factors using electrical energy. These 3D thermochromic micropatterns using the CREW method can be extended to various fields, including sensors, clothing, and anti‐counterfeiting.