U.S. patent application 20180021169 (applicant ALPS South LLC, St. Petersburg, Fla.):
"A soft thermoformable elastomer with a phase change material exhibiting high latent heat of fusion. The compound provides elasticity, softness, formability, and heat over an extended duration and to facilitate prolonged skin contact at elevated temperatures. Used in combination with active ingredients the increased temperature and formability provides enhanced transdermal delivery through the skin. Thermoplastic elastomers may be manufactured by mixing together plasticizing oil, a triblock copolymer, a paraffinic substance and one or more additives, e.g., an antioxidant, an antimicrobial agent, and/or other additives to form a mixture which melted then cooled into the thermoplastic elastomer. During cooling, the thermoplastic elastomer may be molded or otherwise formed into any number of articles including, but not limited to, prosthetic liners, prosthetic sleeves, external breast prostheses, breast enhancement bladders, masks, wound dressing sheets, wound dressing pads, socks, gloves, malleolus pads, metatarsal pads, shoe insoles, urinary catheters, vascular catheters, and balloons for medical catheters both vascular as well as urinary."