US 7,252,915 B2 · Magnetic mono-component toner composition

Abstract

The present invention relates to a magnetic mono-component toner composition, and more particularly to a mono-component toner composition that comprises magnetic toner particle comprising a binder resin, a magnetic component, and a charge control agent; a hydrophobic treated silica having a specific surface area of 20 to 80 m2/g; a hydrophobic treated silica having a specific surface area of 130 to 230 m2/g; and a metal oxide fine powder. A magnetic mono-component toner composition of the present invention has such good flowability that it provides smooth toner supply even when the developing roller surface has been worn due to long time use, and it has such excellent uniform chargeability that it prevents image deterioration (“wave” patterns of toner may form on developing roller, that is, magnetic sleeve) by forming an uniform toner layer on the developing roller.

Claims7

Dependent claims

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 m2/g;
c) 0.5 to 2.5 parts by weight of a hydrophobic treated silica having a specific surface area of 130 to 230 m2/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.

7 more elements

Dependencies are inferred from the claim text.

Magnetic mono-component toner composition

Life of this patent

Magnetic mono-component toner composition

Life of this patent

Abstract

Claims7