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AssigneeDianippon Ink and Chemicals, Inc.
InventorsMinoru Nomura, Hitoshi Takayanagi, Kenichi Hirabayashi, Takashi Ito, Kazuo Itoya, Masahiro Yoshida
Estimating the term…
A spherically particulate toner characterized by a volume-average particle diameter of from 1 to 6 μm, a colorant content of not less than 9.1% by weight, particularly not less than 5% by weight when the colorant is an organic chromatic pigment, based on the total weight of the binder resin and colorant used and an average circularity (average of circularity defined by (perimeter of circle having the same area as the projected area of particle)/(perimeter of the projected image of particle)) of not less than 0.98. The spherically particulate toner according to the present invention gives an excellent image quality and can be consumed in a drastically reduced amount per sheet of printing paper. By predetermining the particle size distribution of spherical toner particles and the added amount of inorganic oxide fine particles to optimum values, the image quality can be further improved.
A spherically particulate toner comprising a colorant and a binder resin, wherein said toner has a volume-average particle diameter of from 1 to 6 μm, the content of the colorant is not less than 9.1% by weight based on the total weight of the binder resin and the colorant, and said toner has an average circularity (average of circularity defined by (perimeter of circle having the same area as the projected area of particle)/(perimeter of the projected image of particle)) of not less than 0.98.
A spherically particulate color toner comprising a colorant and a binder resin, wherein said toner has a volume-average particle diameter of from 1 to 6 μm and an average circularity (average of circularity defined by (perimeter of circle having the same area as the projected area of particle)/(perimeter of the projected image of particle)) of not less than 0.98 and said colorant is an organic chromatic pigment and the content thereof is not less than 5% by weight based on the total weight of the binder resin and the colorant.
A spherically particulate toner characterized by comprising a colorant and a binder resin, wherein said toner has a volume-average particle diameter of from 1 to 6 μm, the content of the colorant is not less than 9.1% by weight based on the total weight of the binder resin and the colorant, said toner has an average circularity (average of circularity defined by (perimeter of circle having the same area as the projected area of particle)/(perimeter of the projected image of particle)) of not less than 0.98, and said binder resin comprises a polyester resin.
A spherically particulate color toner characterized by comprising a colorant and a binder resin, wherein said toner has a volume-average particle diameter of from 1 to 6 μm, the colorant is an organic chromatic pigment and the content of the same is not less than 5% by weight based on the total weight of the binder resin and the colorant, and said toner has an average circularity (average of circularity defined by (perimeter of circle having the same area as the projected area of particle)/(perimeter of the projected image of particle)) of not less than 0.98, and said binder resin comprises a polyester resin.
Dependencies are inferred from the claim text.