White Paper: High-Performance, Light and Moisture Dual-Cure Automotive Conformal Coating



Light-curable materials can provide significant benefits over conventional technologies, including lower operating costs driven by lower labor needs, space savings, lower energy demand, and higher throughput. A key advantage to light-curable conformal coatings is the ability to use a non-solvated “green” (100% solids) material. Conformal coatings are used to enhance long term reliability of automotive electronic parts. Key properties include resistance to rapid and extreme temperature changes, as well as protection against high heat-humidity, chemicals such as gasoline, and corrosive materials like salt and sulfur.

We have developed a 100% solids conformal coating that is light and moisture dual-curable, and exhibits an excellent balance of properties and premium performance. Secondary moisture curing allows material under shadow areas to cure helping to eliminate concerns about uncured material on the printed circuit board (PCB). We will discuss the performance of this material when compared to other light-curable materials, as well as other chemistry types of conformal coatings, in reliability tests such as heat and humidity resistance (85°C, 85 % relative humidity), thermal shock resistance (-55°C to +125°C) and corrosion resistance (flowers of sulfur, salt spray and common automotive fluids). Any changes in physical appearance including any formation of oxidation spots was assessed, and electrical insulation performance was recorded both before and after reliability testing.