Offered as an alternative to traditional metal and plastic electrically conductive parts, a direct printing process can apply patterned conductive and dielectric thick film coatings onto disposable medical device components made of polyphenylsulfone (PPSU) resin. Micropen Technologies Corp, Alpharetta, GA, paired its Micropenning direct printing process with the Radel PPSU resin from Solvay Advanced Polymers, Brussels, in order to create a disposable component for a spinal therapy system that offered high electrical and mechanical reliability.

After testing a range of materials, the PPSU demonstrated resistance to chemical abuse and high heat as well as provided secure film adhesion and biocompatibility. These traits are essential for bonding with the printing process and creating the quality disposable electrode. The direct printing process combines precision motion control with the ability to dispense materials, such as thick film polymeric inks, in a designed pattern with accuracy for widths down to 50 µm. This process is also suited for medical devices with radiopaque markers and drug dosing features.

The disposable electrode that combines the printing process with the PPSU resin is made by depositing a conductive silver ink on the exposed surface of an injection molded component. Measuring approximately 9 in. long by 0.25 in. wide with various thickness options, the component is subjected to solvents, UV radiation, and temperatures up to 302ºF. These testing parameters demonstrate the product’s flexibility and fracture strength, which enables it to withstand repeated bending.