Issue link: https://iconnect007.uberflip.com/i/1475604
AUGUST 2022 I DESIGN007 MAGAZINE 83 Wagner: Sure, a lot of common materials, poly- carbonate for in-mold electronics. Shaughnessy: P r i n t e d h e a t e r s need complex control systems to work correctly. What do you think? Wagner: ere are PTC heaters that are basi- cally self-regulating, and many are used in the automotive industry—just simple co trols. You can get into more complex controls with fixed-resistance type heaters. But it's not that complex for things like wearables where you're not cooking anybody at those tempera- tures. Bianchi: e PTC printed heater is probably the simplest. You just need to put power to it, and it regulates its temperature on its own. You don't need much for a microcontroller at all if anything. Wagner: You pick the right ink and the right design, and it's pretty self-sufficient as far as regulating itself. Shaughnessy: Finally, printed elec- tronics cannot be used with sol- dered components. I 've heard that it's doable but difficult. Bianchi: If you're using a low-temp solder, you can use a solder. It's more common to use a conductive epoxy to go onto a silver ink, pri- marily because it's usually printed on a polyes- ter circuit or a polyester sheet. A solder would be too hot for the polyester, so we use conduc- tive epoxy instead. Wagner: Some companies have perfected their own IP to do some soldering onto PET when they're putting down specific inks and things like that on the soldering pads and then put- ting them through reflow ovens, but it's not common per se through the industry. Bianchi: But more importantly, you can surface mount components onto printed electronics. Wagner: Yes. You're just dispensing conductive epoxy and then using the same pick and place machine to put components on. You can even screen print an epoxy paste as well. Shaughnessy: ank you everyone for address- ing these myths today. DESIGN007 Editor's note: Watch for the continuation of this roundtable discussion in next month's issue. Tom Bianchi