Patent ID: 7273686
Filing Date: 2007-09-25
Classification: G03G

Abstract:
1. A magnetic toner comprising toner particles which comprise toner base particles containing at least a binder resin and a magnetic material, and inorganic fine particles, wherein: the toner base particles have been obtained through a pulverization step; wherein, in wettability of the toner base particles to a methanol/water mixed solvent, the methanol concentration at the time the transmittance of light of 780 nm in wavelength is 80% and the methanol concentration at the time the transmittance thereof is 50% are from 35% by volume to 75% by volume; the toner base particles having a circle-equivalent diameter of from 3 μm or more to 400 μm or less as measured with a flow type particle image analyzer have an average circularity of from 0.935 or more to less than 0.970; and the toner base particles have an average surface roughness of from 5.0 nm or more to less than 35.0 nm as measured with a scanning probe microscope; and the magnetic material is used in an amount of from 20 parts by weight or more to 200 parts by weight or less based on 100 parts by weight of the binder resin.