Earlier quoted context omitted.
OK this literally is quantum physics and the discovery was Nobel-prize material but it's not that hard to grasp so here's how it works :) If you have a chemical reaction that requires a certain energy level, shining lots of light on it won't help much if each individual photon is below that energy level. Even if you have a really bright reddish light, each photon still only has a relatively low energy. On the other h…
So it just needs energy to solidify? Would heat also work? So the molecules that it's made of up combine into new molecules that are solid? Do you know what the chemical reaction is?
I've also googled around and found this picture explaining what is called uv curing. http://www.signindustry.com/flatbed_UV/articles/images/2008-...
So basically the uv light is kicking the electrons up multiple levels in the "photoinitiators", the "photoinitiators" stabilize by dropping levels and giving off photons. These photons excite the "Monomers" and "Oligomers" between which electrons can freely flow (radicals) making it possible to form new bonds, creating longer chains of atoms (a polymer) /amateurexplenation