The compound annual growth rate (CAGR) for the global chip-on-board (COB) LED market will be just over 40 percent through 2018, according to analyst firm Research and Markets. Dow Corning, a global leader in silicones, silicon-based technology and innovation, expects the continued expansion of enabling materials technologies, such as moldable optical silicones, to help fuel growth in COB packaging and other innovations along the entire LED lighting value chain.

"Interest in Dow Corning's highly moldable and photo-thermally stable optical LED silicones has steadily grown as our global customers and collaborators increasingly call for higher performing alternatives to conventional glass, epoxies and plastics," said Kaz Maruyama, global industry director, Lighting Solutions at Dow Corning. "While LED-based general lighting has introduced new growth opportunities for Dow Corning, our advanced silicone technologies are also opening up once unimaginable new design options for brighter and more reliable solid-state lighting."

Conventional glass and organic materials drove development of low power LEDs for mobile device displays and flat panel televisions. However, as LEDs began to compete for general lighting applications, such as streetlights, office illumination and architectural lighting, these traditional materials imposed various design limits with regard to the increasing heat, output efficiency and innovative architectures of COB and other high-brightness LED concepts.

The recent emergence of moldable optical silicones, however, signaled a quantum leap for LED materials technology, and these advanced materials are now enabling LED lamp and luminaire designs to progress exponentially rather than linearly.

Because they can be formulated as optically transparent or bright white reflective materials, optical silicones offer much more than easily moldable substitutes for glass optics or aluminum reflectors. Silicones will maintain photo-thermal stability when exposed to temperatures of 150°C and higher. In effect, the combined design and processing flexibilities offered by these materials are helping to actively redefine the boundaries of LED module, lamp and luminaire design from the bottom up.

Most optical silicones process as low viscosity liquids, and cure into flexible materials of varying hardness. Their easy processability often translates into reduced assembly and lower cost of ownership. More importantly, they enable unique design features and finished parts that would be impossible to achieve with harder materials, such as undercuts, highly precise micro-optical features and multi-functional parts like integrated gaskets and optics. Innovative LED components made possible with these advanced materials solutions also include larger or thicker optics that resist warp, unique 40° reflectors that deliver beautiful light distribution and molded mixing chambers that efficiently diffuse white light.

As lamp and luminaire manufacturers seek to deliver more lumens per dollar, many are looking to optical silicones to help minimize their products' total cost of ownership through improved performance and processing. Plus, the compatibility of transparent and reflective silicones offers unique options for co-molding optical elements with these properties to form single parts to both reduce assembly costs and optimize optical performance.
Lastly, the thermal and optical stability of silicones combined with their strong resistance to ultraviolet light, chemicals and impact helps ensure LED light sources deliver consistent, reliable, high-quality illumination over the lifetime of the device.

"The LED industry's interest, adoption and innovative applications of Dow Corning's moldable optical silicones has accelerated in pace with overall industry growth in COB and other next-generation LED lighting designs," said Maruyama. "And our conversations with current and prospective customers indicate that this versatile materials technology has only just begun to show its potential for enabling exceptional breakthrough designs."

A market leader in materials, expertise and collaborative innovation for LED lighting concepts, Dow Corning offers solutions that span the entire LED value chain, adding reliability and efficiency for sealing, protecting, adhering, cooling, and shaping light at a more affordable price across all lighting applications.