Resistant Epoxy is Key to Expanding Display Terminals
The development of epoxies with low thermal-expansion rates is a critical factor in the recent move towards larger liquid crystal displays (LCDs). Many instrument and consumer-product manufacturers are using larger LCDs to provide users with a simpler interface, as well as more monitoring and control functions. This trend creates the need for DC-AC inverters capable of withstanding higher amounts of heat over continuous-duty cycles. The most critical component is usually the epoxy used to encapsulate the windings of the inverter. It must be able to withstand large temperature shifts without cracking, which would lead to an inverter failure and a black display.
This challenge is being overcome by the development of epoxies with ever-lower coefficients of thermal expansion that enable them to encapsulate high-power inverters without failure. For example, the 840 ventilator system, recently introduced by Nellcor Puritan Bennett (NPB), Carlsbad, Calif., has two large displays, both of which are powered by a single E2019 inverter from Endicott Research Group (ERG), Endicott, N.Y.