Patent ID: 7252915

Claim:
A magnetic mono-component toner composition, which comprises: a) 100 parts by weight of magnetic toner particle comprising: i) a binder resin in an amount of 30 to 80 wt % of the magnetic toner particle; ii) a magnetic component in an amount of 20 to 70 wt % of the magnetic toner particle; and iii) a charge control agent in an amount of 0.15 to 4 wt % of the magnetic toner particle; b) 0.5 to 1.5 parts by weight of a hydrophobic treated silica having a specific surface area of 20 to 80 m 2 /g; c) 0.5 to 2.5 parts by weight of a hydrophobic treated silica having a specific surface area of 130 to 230 m 2 /g; and d) 0.3 to 1.5 parts by weight of a metal oxide fine powder based on the magnetic toner particle, wherein d) the metal oxide fine powder is one or more mixtures selected from a group consisting of titanium dioxide, zinc oxide, magnesium oxide, cerium oxide, iron oxide, copper oxide, and tin oxide.