UV/EB-Curable Acrylate Silicones for Release Coatings
UV silicone release coatings are cured by adding 2.0% to 2.5% free-radical photoinitiator. Although there are many potential photoinitiators for these silicones, we prefer those that are oligomeric in nature (oligo = "a few," mers = "units") because "highly flexible" silicones fail to retain many of the "out-gassing," post-UV monomeric photoinitiator by-products. In this study, all coatings were UV-cured with 2.0% ESACURE 100F (70% oligomer and 30% liquid photoinitiator, available from Lamberti USA Inc.)
The test results show that these acrylate-silicone blends are highly release-stable against this very aggressive acrylic PSA tape, even at such high aging temperatures and for such long periods of time. PC 910, with its "end chain" acrylate functionality, its long polymer chain and its high methyl-to-acrylate ratio gives the lowest, most stable release of these two CRA-minus release modifiers.