Black toner for electrophotography
AssigneeMita Industrial Co., Ltd.
InventorsMasahiko Kubo, Akihiro Watanabe, Takafumi Nagai, Hironori Maruyama
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Abstract
Black toner for electrophotography used for visualizing an electrostatic latent image formed on an image-holding body is provided which includes a resin binder and carbon black dispersed in the resin binder. The carbon black has a volatile component content of 4% or more, a structure index of 100 or more, and a mean grain size in the range of 20 to 35 nm.
Claims14
Black toner for electrophotography used for visualizing an electrostatic latent image formed on an image-holding body together with color toner, the black toner comprising:
- a resin binder and carbon black dispersed in the resin binder, the carbon black having a volatile component content of 4% or more, a structure index of 100 or more, and a mean grain size in the range of 20 to 35 nm,
- wherein the conductivity ratio of the black toner to the color toner is 2.0 or less.
A method for forming an image by visualizing an electrostatic image formed on an image-holding body, comprising the steps of:
- forming a black image by using black toner for electrophotography comprising a resin binder, and carbon black dispersed in the resin binder, the carbon black having a volatile component content of 4% or more, the structure index of 100 or more, and a mean grain size in the range of 20 to 35 nm;
- and
- forming a colored image by using a mixture of magenta, cyan and yellow toner,
- wherein the conductivity ratio of the black toner to each magenta, cyan and yellow toner is 2.0 or less.
A composition comprising at least one resin binder, and carbon black dispersed in said resin binder, the carbon black having a volatile component content of about 4% or more, a structure index of about 100 or more, and a mean grain size in the range of about 20 to about 35 nm.
Dependencies are inferred from the claim text.