The Superhero of Xerography
One of Chester Carlson’s greatest challenges was finding a way to bring out the latent
photoelectric image created on the surface of the sulfur-coated slides in his early
experiments. He found an early winner in lycopodium powder, a yellow-tan dust-like substance manufactured from moss spores. Used traditionally in fireworks and
as an early flash powder, when negatively charged, the fine particles adhere to the
positively charged image created by exposing the sulfur-coated slide to light.
In his first experiments, Carlson needed to fix the image by using heat to transfer it
to wax paper. By the time the first working xerographic equipment made its way to
the office setting, toner technology had advanced to include first waxes, and then
polymers, which were able to be fused to plain paper by a heating element as a final
step of the xerographic process.
Toner has come a long way since then. From carbon black to a multitude of colors,
advances in toner have been one of the major drivers of increased copy quality over
the decades since the “10-22-38 Astoria” copy.
Today, in addition to pigment, toner technology includes additives that increase
adhesion, hold a better charge and move through the machine more efficiently. There
are also new methods of producing the toner particles, for example, Xerox® exclusive
emulsion aggregation (EA) technology. EA toner saves energy while improving copy
quality with an extremely small, uniform size for less toner mass per page and lower