Masayasu Anzai

Electrophotographic Properties of an Organic Photoconductor and a Triboelectric Magnetic Toner for a New Diode Laser Printer

The electrophotographic properties of a newly developed organic photoconductor and triboelectric magnetic toner were investigated for a nonimpact printer with a diode laser. The photoconductor was composed of a metal-free phthalocyanine layer and an oxazole-derivative-doped polymer layer. The photoconductor had a charge acceptance of -1000 V and a light sensitivity of more than 0.1 m2/mJ at 780 nm. The magnetic toner had a resistivity as high as 1014 ¿ cm and could accept triboelectric charge of -3.5 ¿C/g. Chrome dye was employed for a negative charge control agent to affect the sign and magnitude of triboelectric charge on toner particles. Using the developed organic photoconductor and triboelectric magnetic toner, good quality prints on plain paper were obtained with the new diode laser printer. Toner mass density deposited on the photoconductor was improved by more than 20 percent as compared with that of conventionally used conductive or high-resistance magnetic toners. It was found that the triboelectric magnetic toner had a very high transfer efficiency of as large as 80 percent, even on plain paper.