Thermally conductive adhesives in the thermal management of LED lighting
Light-emitting diodes, LEDs for short, can emit light as soon as electrical current flows in the forward direction. Decades of development has led us to the LED light sources as we know them today, these enjoy a widespread popularity, and their numerous different properties allow access to new design options.
With the introduction of LED technology, bonding is also finding its way into the lighting industry for several reasons. In contrast to conventional light sources, the LED is not a thermal emitter. This means that light is not created by heating a filament, but by emitting photons. Nevertheless, unintentional heat is generated when operating an LED. Unfortunately, the operating temperature of the LED has a direct influence on the efficiency and service life, which makes it essential to dissipate the heat generated. A long service life can therefore be guaranteed if the LED light is thermally connected to a heat sink. This is when thermally conductive adhesives are required; they are an interesting alternative to frequently used foils or thermal pastes, as they enable heat transfer and ensure a stable mechanical connection as well, which makes additional fastening mechanisms trivial. Thermally conductive adhesives based on epoxy resin, which provide high-strength, non-aging bonds on a wide variety of substrates, have proven to be particularly useful here. These are available as one- or two-component systems. One-component products must be cured at temperatures above 100 °C, whereas two-component epoxy adhesives can also be cured at room temperature and are therefore preferred for bonding LEDs to heat sinks.
Two-component adhesives are processed with the help of automated mixing and dispensing technologies. For small series and / or manual processing, products are also available that are simply processed from side-by-side cartridges. The two components are mixed simply by squeezing them out of the two chambers of the cartridge with the aid of a dispensing gun via the static mixer that comes with the cartridge.
Polytec PT offers an extensive range of thermally conductive adhesives with graded thermal properties, suitable for various application and curing techniques. Benefit from our diverse expertise in thermally conductive bonding. A contact, that conducts!