Abstract
Air contaminants emitted from printers in an office, such as volatile organic compounds (VOCs) , particles, and ozone, have become a serious issue in relation to the health effects. In the present work, the particles emitted from various printers (an ink-jet printer, three monochrome laser printers and a color laser printer) in the size range of submicrometer or smaller were characterized by measuring the emission rate, the size distribution and the charge distribution. The stability of emitted particles in dry air was also studied by introducing them into a diffusion dryer. As a result, it was found that the total particle emission rate from the ink-jet printer was in the order of 106 particles per sheet during printing, while that from monochrome laser printers was in the order of 107 during printing and the same concentration of particles were measured when a sheet of paper was passed through the printer without printing. Most of the particles were smaller than 0.1μm, indicating that they are not directly derived from the toner or main ink droplets. The stability test showed that the particles emitted during printing are composed of nonvolatile species and water.
