One of the more recent introductions to cyanoacrylate technology are UV-curable grades. These are modified ethyl-based products with added photoinitiators absorbing UV light in the UVA region (around 365 nm). Light-curing cyanoacrylates cure almost immediately to a hard, tack-free finish in less than 3 seconds when exposed to high — intensity UV light. Whereas most cyanoacrylates require a thin bond line (<0.2 mm), the UV-curing cyanoacrylates will cure through depths up to 5 mm or 6 mm when exposed to the appropriate light source. The adhesive that has been applied in areas not exposed to light then cures by the residual moisture mechanism found in regular cyanoacrylates.
Light-curing cyanoacrylate adhesives provide processing and performance benefits for high-speed assembly processes. They offer high bond strength to a wide variety of substrates and achieve high performance with guaranteed complete cure.