LED UVA-CURABLE CONFORMAL COATINGS WITH HIGH PROTECTIVE QUALITIES

摘要

UV Curable conformal coatings have attained widespread use in applications which require fast through-put times, such as Automotive and Industrial Control manufacture. In addition to speed of cure, UV curable conformal coatings have the advantage of high physical protection and chemical resistance for electronic systems. Traditional UV-cure of coatings is, however, an energy intensive process, using high power mercury discharge lamps, which also produce high amounts of heat and ozone. The recent introduction of new, high output LED UVA light units allows the effective cure of conformal coatings. These light units use between 365nm and 395nm wavelength of UVA light, which provide effective cure with minimal heat and no ozone generation. LED UVA curable conformal coatings are now available which are specifically designed to cure with LED UVA light units. UVA light is known to penetrate organic polymers effectively; this effect helps provide coatings with high physical stability. The most recent LED UVA coatings meet and exceed the protective qualities seen in earlier coatings designed to be cured by mercury discharge lamps. This paper describes the advantages of LED UVA-cure, the development of new coatings designed exclusively for LED UVA-Cure, and details recent development work conducted by Humiseal to improve the performance of traditional UV-curable coatings by supplementing mercury discharge cure with LED UVA-Cure to improve coating properties.