Free Radical

An extremely reactive atom or molecule bearing an unpaired electron that destabilizes other atoms or molecules. Free radicals are typically produced as the products of other chemical reactions (such as combustion). Their presence in several types of printing ink vehicles (in particular those of radiation-curing inks) starts rapid chain reactions that cause the polymerization of the vehicle, which hardens to a dry ink film containing the pigment (called free radical polymerization).

All text and images are licensed under a Creative Commons License
permitting sharing and adaptation with attribution.

PrintWiki – the Free Encyclopedia of Print