In the image developing process, the latent electrostatic image on the photoconductive surface is converted into visible by the deposition of the toner particles on the photoconductive surface. The toner is either dual components or mono-component developers.In the mono-component development system, the magnetic toner is held by the magnetic forces on the sleeve, the toner is moved around the sleeve spaced several hundred micrometer from the photoreceptor, under the electric field the magnetic toners jump over the gap onto the photoconductor.It is found that, the optical density and the background of the printed image is dependent on the relative humidity of the toner. Hence, we investigate the causes by the measurement of Q/M or Q/A of the toner under different humidity. As the humidity increases, the water film will induce the instability of the electric charge, so the Q/M will decreases, but Q/A. increases.
Liu Howard, Hungjing Tiong, "The Effect of Relative Humidity on the Toner in the Developing Process" in Proc. IS&T Int'l Conf. on Digital Printing Technologies (NIP17), 2001, pp 848 - 851, https://doi.org/10.2352/ISSN.2169-4451.2001.17.1.art00093_2