LED UV-Curable Black Epoxy Adhesives

Black Epoxy Adhesives Cured with LED UV Energy Panacol has introduced a new adhesive technology with its "Black & Light" adhesives: deeply cured black epoxies. The black epoxy adhesives in Panacol's Vitralit® product range can now be cured with UV light sources in thicker layers without requiring secondary hardening mechanisms. A significant drawback of conventional black UV adhesives is this: black color absorbs a large portion of UV intensity, meaning the energy required to fully polymerize an adhesive can only penetrate a few micrometers deep. This results in surface "shell" formation on black adhesives, but does not provide complete curing. They must subsequently be cured in a secondary thermal curing process at temperatures above 100°C. Panacol's new "Black & Light" technology enables black epoxy adhesives to be fully cured with LED UV energy. The curing depth can range from a few hundred micrometers to several millimeters. Such adhesives are suitable for encapsulation in electronics manufacturing, over-ball or edge bonding, and also for optical adhesive systems where high OD values (optical density) are required. They are also suitable for optoelectronic applications to help minimize reflections and improve sensor transmission values. A manufacturing process using "Black & Light" technology works as follows: the black adhesive is dispensed and cured with appropriate wavelength and intensity. During the curing process, the "Black & Light" technology within the adhesive allows UV rays to penetrate and complete full curing. After the adhesive polymerization is complete, the "Black & Light" technology structure blocks light transmission, creating a fully cured and irreversibly black adhesive system. "Black & Light" technology is compatible with many of Panacol's Vitralit® epoxy adhesives. Custom adhesive solutions can be created to meet requirements for light blocking amount and curing depth. "Black & Light" adhesive systems can be specifically tailored to the characteristics of the relevant application. Another important advantage of "Black & Light" adhesives is storage. Many single-component black epoxies require deep frozen transport and storage. "Black & Light" epoxy adhesives can be stored and dispensed at room temperature and under normal refrigeration conditions. Source