A measure against the latest problem of LED package

Abstract

LED light has the many merits including longer life, electric power saving, small size and light weight. Many new products with LED have been produced, and those products are used in our lives. However, there are some reports that the LED light darkens and is not turned on. This phenomenon is frequent at the place that produces the sulfur based gas such as a hot-spring resort or the rubber factory. The sulfur based gas in air penetrates silicone resin, because the silicone resin which seals the LED package has permeability to gas. And it arrives at the silver plating of the LED package bottom. As a result, black silver sulfide is produced by a chemical reaction of silver sulfur. This is the cause of the problem. Much silicone resin makers propose the silicone resin which incorporated the phenyl to solve this problem. However, the silicone resin which incorporated the phenyl degrade easily by heat or UV. I planned improvement by incorporating the isocyanuric acid structure in silicone resin, because isocyanuric acid has good heat resistance. I succeeded in incorporating the isocyanuric acid structure in a hardening reaction of the silicone resin by combining the isocyanuric acid derivative including the allyl with the silicone resin of the addition reaction type. Water vapor permeability of the resin fell to half of the normal methyl silicone resin, as a result. In addition, it was confirmed to be improved about the sulfuration of the silver plating of the LED package bottom. This result suggest that the silicone resin which incorporated the isocyanuric acid structure can improve the issue of LED deterioration by the sulfur based gas.