Quantifying Photoinitiator Migration Kinetics in Polyolefin Packaging Stacks
Quantifying photoinitiator migration in polyolefin stacks requires coupled Fickian diffusion modeling and LC-MS/MS verification to control set-off and trans-barrier flux.
Omnirad 907
Meaning
Through-cure performance in pigmented systems is achieved by using alpha-amino ketone photoinitiators that absorb light at specific wavelengths. Omnirad 907 is specifically designed for use in offset and screen printing inks where high opacity is required. This initiator allows UV light to penetrate deep into the ink layer.
Absorption Spectrum
Peak sensitivity occurs in the long wave UV region which is less shadowed by pigments like titanium dioxide or carbon black. Using omnirad 907 ensures that the bottom of the ink film cures as thoroughly as the surface. Incomplete cure leads to poor adhesion and smearing of the printed image.
Ink Performance
High reactivity allows for high speed printing on non-porous plastic substrates. Adding omnirad 907 to a formulation improves the scratch resistance and chemical durability of the cured film. It is often used in combination with other initiators to broaden the spectral response of the system.
Formulation Stability
Liquid forms of this chemical remain stable in the ink bottle for extended periods without premature gelation. Storage temperatures must be kept within the recommended range to prevent crystallization or loss of activity. Successful use depends on the correct ratio of initiator to monomer to achieve the target physical properties.