Black epoxies for effective UV curing 12 April 2024

Panacol has introduced its first series UV curable, black epoxy resin adhesives - Vitralit® BL UC 1101, Vitralit® BL UC 1102 and Vitralit® BL UC 1103, known as ‘Black&Light’ technology, specially designed to be cured in thicker layers using only UV light, eliminating the need for a secondary curing mechanism.         

A conventional black UV adhesive absorbs a high percentage of the UV curing energy, meaning the UV light energy required to fully polymerise an adhesive only penetrates a few micrometres. This phenomenon leads to the formation of a superficial ‘skin’, while the adhesive underneath remains uncured. The new black Vitralit® BL UC adhesives can be cured to greater than 1mm in thickness, purely with UV LED light.

UV LED curing systems from Dr Hönle are perfectly matched to the absorption wavelengths of the Black&Light technology, ensuring optimal curing of the black adhesives.

Covering a wide range of applications including component encapsulation, glob top, or edge bonding in electronics production, these adhesives can also be used in applications requiring high optical density values. Panacol also highlights that another major benefit includes room temperature shipping and storage, as usually conventional single component, black epoxy adhesives must be transported and stored cold or deep frozen.   

Panacol recommends Vitralit® BL UC 1101 if a thick layer of adhesive is needed. It cures reliably in thick layers up to 1.3mm, resulting in an optical density of up to 3.9. If a high optical density in lower layer thickness is needed, Vitralit® BL UC 1103 with optical density values up to 6 is the best option. In optoelectronic component assembly, Vitralit® BL UC adhesives minimise reflections and can safeguard the sensitive transmission values required for automotive sensors. 

All three adhesives offer outstanding mechanical properties, including high glass transition temperatures, low shrinkage, and low coefficient of thermal expansion. Those characteristics ensure reliable bonding results with an excellent thermal and positioning stability. As the Black&Light technology is compatible with many Vitralit® epoxy resin adhesives from Panacol, individual adhesive solutions matching specific curing conditions and/or mechanical properties are possible.

Becca England Assistant Editor t: +44 (0) 1727 615 413

Becca is the latest member to join our team and is eager to get stuck into the world of fasteners. She brings an enthusiastic and fresh outlook on what we do editorially and will be leading our social media activity – including sourcing material, editing articles and posting online.