Conductive coatings offer cost-effective, easy-to-apply method for shielding plastic medical equipment enclosures

Conductive paints give designers a great deal more choice and flexibility versus traditional approaches when looking to easily and cost effectively shield their plastic enclosures and equipment housings against electromagnetic interference, provide anti-static protection, corona shielding, surface grounding, and corrosion protection. Materials such as Chomerics’ CHO-SHIELD ® 2056 which consists of silver-plated-copper/silver particles in a single-component acrylic resin, can be used at minimal thicknesses instead of processes such as vacuum metalization and electroless plating. Unlike competing technologies, Chomerics’ coatings can be applied without the need for expensive specialised equipment using a standard high volume/low pressure (HVLP) spray system.
Shielding effectiveness levels of greater than 75dB (between 50 MHz and 10 GHz) can be achieved with silver fillers offering the highest shielding performance, followed by silver-plated copper and copper and nickel. The choice of fillers gives designers a range of shielding performance / cost options.
Depending on production volumes, customers can opt to either manually apply the conductive paint or utilise robotic techniques that support higher throughput and also maximise repeatability. Advanced paint formulations give excellent self-levelling and uniformity characteristics resulting in even shielding performance across the part.