Toner is a
powder used in
laser printers and
photocopiers to form the printed text and images on the
paper, in general with a
toner cartridge. In its early form it was a mix of
carbon powder and
iron oxide. Then, to improve the quality of the printout, the carbon was melt-mixed with a
polymer. Toner particles are melted by the heat of the fuser, and are thus bonded to the paper.