Depending on the type of plastic used, the marking can vary from white to black. Laser marking of polymers relies on carbonization or foaming processes caused by laser beam absorption. Carbonization (a thermochemical process) produces dark marks. Foaming, a partial degradation creating gas-bubbles with in the material, scatters the light and produces light marks. All types of marking can be acieved on many plastics, including photo quality imades on identification cards.
