Ricoh Company, Ltd.

Ryuta Chiba

Shinya Nakayama

Hiroshi Yamada

Tsuyoshi Sugimoto

Tsuneyasu Nagatomo

Hideyuki Santo

Suzuka Amemori

Kohsuke Nagata

Takahiro Honda

Masana Shiba

Hiroshi Yamashita

Masaki Watanabe

Minoru Masuda

Shinsuke Nagai

Osamu Uchinokura

Naohito Shimota

Akinori Saitoh

Susumu Chiba

Hiroyuki Takeda

Akihiro Takeyama

A toner, including: a polyester resin, wherein the polyester resin has a structure represented by any one of formulas 1) to 3) below: 1) R1-(NHCONH-R2)n-, 2) R1-(NHCOO-R2)n-, and 3) R1-(OCONH-R2)n-, where n is 3 or more, R1 represents an aromatic organic group or an aliphatic organic group, and R2 represents a group derived from a resin that is polyester formed of polycarboxylic acid, polyol, or both thereof; or that is a modified polyester obtained by modifying polyester with isocyanate. 

Toner, toner accommodating unit, and image forming apparatus

A layered inorganic mineral including a surface treated with a fluorine-containing compound, where the layered inoganic mineral that can be favorably used for a toner that is excellent in high charging ability, charging stability, and low temperature fixing ability, and that can exhibits high reliability during cleaning.

Layered inorganic mineral, toner, and image forming apparatus

A toner, including: base particles containing a polyester resin, a colorant, and a release agent, wherein the toner has a glass transition temperature (Tg1st) of 20&#xb0; C. to 50&#xb0; C. where the glass transition temperature (Tg1st) is measured in first heating of differential scanning calorimetry (DSC) of the toner, wherein tetrahydrofuran (THF) insoluble matter of the toner has a glass transition temperature [Tg2nd (THF insoluble matter)] of 30&#xb0; C. or lower where the glass transition temperature [Tg2nd (THF insoluble to matter)] is measured in second heating of differential scanning calorimetry (DSC) of the THF insoluble matter, and wherein 50% or less of the colorant is present within a region of 1,000 nm from a surface of each of the base particles toward a center thereof.

Electrostatic image developing toner, developer, and image forming apparatus

A magenta toner for electrophotography, including:

Magenta toner, developer, and image forming apparatus

A toner contains a binder resin, a colorant, and a releasing agent, wherein the toner contains toner particles, and wherein a proportion of the toner particles containing one or more voids having diameters Dof larger than 0.0 &#x3bc;m but 0.5 &#x3bc;m or smaller is more than 5.0% to 60%, and a proportion of the toner particles containing one or more voids having diameters Dof 1.0 &#x3bc;m or larger is 10% or less.

Toner, developer, and image forming apparatus

To provide a toner A containing: base particles, each containing polyester, microcrystalline wax, and a colorant; and spherical silica particles having an average primary particle diameter of 100 nm to 150 nm, wherein the microcrystalline wax has an onset temperature of 45&#xb0; C. to 60&#xb0; C. as determined by DSC, and a carbon number distribution of 25 to 55.

Toner, method for forming toner, developer, and image forming method

A method for producing a toner, including: dispersing toner particles containing at least a binder resin in a first aqueous medium so as to produce an aqueous dispersion; and subjecting the aqueous dispersion to heat treatment, wherein the electric conductivity of the aqueous dispersion after the heat treatment is higher than the electric conductivity of the aqueous dispersion before the heat treatment by 50 &#x3bc;S/cm or less.

Method for producing toner, toner, and image forming method using the same

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Kanagawa, Japan

Ryuta Chiba