On‐Demand Printing of Wearable Thermotherapy Pad

Abstract Thermotherapy is an effective method for pain relief, recovery from injury, and general healthcare. The ordinary heat pad used for thermotherapy at home is not usually tailored to the individual but supplied in a few different pre‐fixed sizes and shapes for mass marketing. A customized wearable heat pad often requires expert support. Herein, an instant, custom‐fit, and on‐demand heat pad for thermotherapy is demonstrated. The heater is directly printed using silver nanoparticle ink on an off‐the‐shelf medical grade tape by inkjet technology. By coating the tape with silica nanoparticles as ink‐absorbing layer and chloride ions as chemical sintering agent, stable heater patterns are printed without the need for subsequent high temperature sintering process. A 3D scanner is used to acquire body information, and a customized heater is produced using the information. The printed heat pad is attached to the shoulder and the effect of thermotherapy is verified objectively through electroencephalography and subjectively through survey. This printed heat pad produced by simple and low‐cost fabrication provides wearable medical devices for personal thermotherapy.