Patent ID: 6875550

Claim:
A non-magnetic single-component toner having toner mother particles and external additives externally adhering to said toner mother particles, wherein said external additives comprise, at least, a small-particle hydrophobic silica for imparting the negative charging property to said toner mother particles and of which mean primary particle diameter is 20 nm or less, a large-particle hydrophobic silica for imparting the negative charging property to said toner mother particles and of which mean primary particle diameter is 30 nm or more and a hydrophobic rutile/anatase type titanium oxide having a work function nearly equal to the work function of said toner mother particles and having a spindle shape of which major axial diameter is in a range from 0.02 μm to 0.10 μm and the ratio of the major axial diameter to the minor axial diameter is set to be 2 to 8, and wherein the work function of said toner mother particle is set to be larger than the work function of said each hydrophobic silica and is set to be nearly equal to the work function of said hydrophobic rutile/anatase type titanium oxide.