1) One more familiar use of electrochemistry that has made its way into the mainstream is xerography, a process for replicating documents that is dependent on photoconductive materials. A photoconductive material is an insulator in the dark but becomes a conductor when exposed to bright light. When a photocopy is being made, an image of a document is projected onto the surface of a rotating drum, and bright light causes the photoconductive material on the surface of the drum to become conductive.

2) As a result of the conductivity, the drum loses its charge in the lighted areas, and toner (small grains to which dry ink adheres) attaches itself only to the darker parts of the image. The grains are then carried to a sheet of paper and fused with heat. When a laser printer is used, the image is projected by means of a laser beam, which creates a brighter light and a greater contrast between lighter and darker areas and therefore results in sharper printed images.