Advancements in UV LED Technology and its Impact on UV Curing Applications

In just the past few years, advances in UV LED technology has been able to provide peak output powers commensurate with and greatly exceeding microwave lamps. Thus, the well-known benefits of an LED-based UV curing system (instant on-off, Hg free, longer life, lower cost of ownership, etc…) may be fully realized. However, the proper combination of peak irradiance, exposure & wavelength remains as a key factor in achieving successful curing performance in even the most standard film chemistries. Substantial gaps remain in formulation development to capitalize the investment of implementing UV LED lamps. This paper will compare the results from various inks and clear coats formulated for LED wavelengths. These formulations compared long-wavelength photoinitiator performance with various synergists using a high power (>25 W/cm2) UV LED system. Comparisons to broad band spectra results from a standard microwave lamp are included.