Toner and image forming apparatus using the same
AssigneeSeiko Epson Corporation
InventorNobuhiro Miyakawa
Life of this patent
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Abstract
The present invention provides a toner which ensures large mean charging amount and excellent transfer efficiency with no or little amount of reversely charged toner and provides an image forming apparatus using the same. The toner is produced by adding external additives to resin particles containing a coloring agent, wherein the external additives are silica particles and modified silica particles of which outer surfaces are modified with oxide or hydroxide of at least one metal selected from a group consisting of titanium, tin, zirconium, and aluminum, the amount of the modified silica particles being 1.5 times or less of the amount the silica particles. The image forming apparatus uses the toner.
Claims12
A toner produced by adding external additives to resin particles containing a coloring agent,
- wherein the external additives are silica particles and modified silica particles of which outer surfaces are modified with oxide or hydroxide of at least one metal selected from a group consisting of titanium, tin, zirconium, and aluminum,
- wherein the ratio of the modified silica particles relative to the silica particles is 0.5 to 2 parts by weight per 100 parts by weight, and
- wherein said silica particles and said modified silica particles are treated by a hydrophobic treatment with an agent selected from the group consisting of a silane coupling agent, a titanium coupling agent, a higher fatty, and silicone oil.
An image forming apparatus which is a full color image forming apparatus having an intermediate transfer medium for transferring an image formed on a photoreceptor onto a recording medium and of which toners are each produced by adding external additives to resin particles, wherein the external additives are silica particles and modified silica particles of which outer surfaces are modified with oxide or hydroxide of at least one metal selected from a group consisting of titanium, tin, zirconium, and aluminum, and wherein the ratio of the modified silica particles relative to the silica particles 0.5 to 2 parts by weight per 100 parts by weight.
Dependencies are inferred from the claim text.