摘要

In this study, emissions of ultrafine particles from a new laser printer were evaluated as a function of toner coverage, number of pages printed, fuser temperature and cartridge rotation during different printing orders. Eight combinations of printing jobs were specifically designed to represent eight printing orders. The toner coverage was found to be an important factor affecting particle emissions from the printer. The printing job without toner coverage (0%) acted as a cleaning process, which would tentatively reduce particle emissions in the next job. Particles generated in printing job with toner coverage (5%) could superimpose onto those emitted from the next job, leading to higher particle number emission in the next job than the previous one. Apart from toner coverage, cartridge rotation was an important factor enhancing particle emissions. Cartridge in rotation mode with/without toner coverage could both cause particle emissions and high fuser temperature. The relationship between the particle emission and the temperature of the fuser unit was very strong (r(2) = 0.96). The regression relationship satisfied a positive power law-rise equation. We also found that ventilation for a long period, printing with no cartridge rotation, and/or printing blank pages before toner page printing could reduce particle emissions.