Attempt to elucidating mechanism for ultrafine particle generation from laser printers using model vapor and suppression of their formation

The emission of ultrafine particles (UFPs) from laser printers has become an issue of great concern in indoor environments. The previous study(3)) revealed that particles generated from the tested laser printers, especially the color one were caused by forming vapors of VOCs, mainly consisting of cyclosiloxanes and adipate ester, and water via the fixing process with a fuser roller, to cool them by surrounding air, and condense water vapor onto the nuclei of VOC droplets. Therefore, we aimed to verify the above-mentioned mechanism for particle generation by replicating the formation process using model vapors of cylosiloxanes generated from heated silicone oil and water. As a result, it was found that the peak size in size distribution of particles generated from the model siloxane vapor shifted to a larger size by adding water vapor even though the size distribution did not resemble that of the color laser printer. In addition, the particles from the model vapors mainly consisted of chain-like siloxanes while those form the printer of cyclosiloxanes.