Stretchable Conductive Ink
Smart clothing only works when all the enabling technologies work. Just like zippers, buttons, and thread support our passive clothing, new technologies that bridge apparel and electronics can support our active clothing. At Loomia, we focus on developing technologies and products that can make our clothing smarter. I think great materiality is important to this industry, so stretchable, direct to fabric conductive inks are useful in the sense that they support making circuited clothing feel like normal clothing.
Stretchable inks are normally deposited onto TPU (thermoplastic polyurethane) and then onto a textile. It sounds like a promising solution, but there have been strong arguments made by Rebeccah Pailes-Friedman and IDTEch Ex Researchers that TPU can pose a problem.
"TPU itself is the first choice of encapsulate but not likely to be the last. This is because it is not the most stretchable thus restricting the clothing-like feeling of e-textiles particularly if large areas are covered. Already companies are experimenting with other material systems..." —iD Tech Ex (Source)