Wearables - those tiny electronic devices that are worn on the skin like a patch - are booming business. They’re flat, flexible and inconspicuous, but highly intelligent: capable of monitoring an individual’s physiological condition during sports and leisure activities or for medical purposes, their uses vary from cosmetic applications to flexible healthcare solutions. And this is only the beginning.
Right now, it’s the group of consumers with an active and health-conscious lifestyle, that is mainly driving the wearables trend. They take steps – literally – to ensure they meet their daily exercise targets. This is a group that tracks their workouts, likes to keep tabs on their body temperature and pulse rate, and even to evaluate their quality of sleep.
But in the future, improved and even smarter products will likely also play a supporting role in medical diagnoses and treatments, and even discreetly deliver medications in precise and accurate dosages. This would, of course, require them to be able to be worn comfortably on the skin for extended periods – which is where an expert knowledge of materials and adhesives is required. The patches must adhere to the skin for as long as is needed, but be able to be removed with minimal discomfort.
Covestro is developing integral and sustainable material solutions that make the wearables more comfortable to wear while also enabling further areas of application.
“Consumers want wearables that cling gently to the skin, and that are also breathable and hypoallergenic,” says Gerd Büschel, a films expert at Covestro. “We’re meeting this need with a clever combination of different materials. The patch is affixed to the wearer by means of a skin-friendly, breathable adhesive, which also is solvent-free and water-repellent. For this the company is offering custom-tailored polyurethane (PU) raw materials.”
The patch is composed of an outer envelope made from thermoplastic polyurethane, which in many cases is laminated with a thermoplastic PU foam under the influence of heat and pressure. In addition to protecting the electronics and ensuring comfort for the wearer, this layer must be as thin as possible to prevent build-up of the adhesive bond. These materials enable the sensor to be embedded in the patch using thermoplastic processing technologies – without resorting to additional wet chemistry. Future development work is aimed at enabling the continuous manufacture of wearables from the reel.
Covestro has a broad spectrum of know-how when it comes to the materials and their processing, and the company is looking for partners along the value chain who are interested in pursuing and coordinating further projects.
This technology and other developments will be on display at the company’s booth at the K 2016 plastics trade fair from October 19 to 26 in Düsseldorf, Germany.
Covestro can be found in Hall 6, Booth A 75.