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.

Conformable on-skin devices for thermo-electro-tactile stimulation: materials, design, and fabrication

“…While many groups employ NWs because the resulting composites are highly transparent, 116 Moon et al used a conductive ink containing Ag nanoparticles that they sintered by adding NaCl to prepare a bendable composite that they could print on different substrates; 117 with a different approach, Weng et al realized a conductive 3D sponge by self-assembly of Ag NW after surface treatment with dopamine: the resulting material could not only stretch and bend but also be compressed and could work as a heater as well among many other applications. 118 Other interesting candidates for conformable heaters are intrinsically conductive polymers (CP).…”

“…136 In order to obtain custom devices, Moon et al proposed to use a 3D scanner to acquire body information which enabled them to print very personalized heaters. 117 In particular, data acquired from 3D scan could help in deciding dimension and shape of the custom heater. The user could select different points on the scan surface and the software calculated the length and width of the single 2D heaters but also how to stitch them together in order to apply the entire film on the interested body surface.…”

The research progress in recording layer of the inkjet printing materials

“…With the development of the information industry and internet technology, inkjet printing has been applied in more and more fields such as computer and digital camera due to its practicability, rapidity and color comprehensive 1–3 . For example, it performs well in the fields of papermaking, home, business office, 3D printing and medical materials 4–9 .…”

Inkjet Printed Heating Elements Based on Nanoparticle Silver Ink with Adjustable Temperature Distribution for Flexible Applications

“…[ 25 ] Other methods are spray coating of Ag nanowire/carbon nanotube composites [ 26 ] or patterned casting of Ag on flexible polymer foil . [ 27 ] Such printed flexible heaters find their application in wearable thermotherapy pads, [ 28 ] paper diagnostics, [ 29 ] and other wearable applications. [ 30 ] Moreover, only a few publications can be found in the field of inkjet printed heaters such as Byers et al with silver microheaters, [ 29 ] Wang et al with silver nanowire flexible transparent heaters, [ 31 ] or Huang et al with silver nanowires for stretchable heaters.…”