Ricoh Company, Ltd.

Ricoh Technology, Ltd.

Akio Takei

Toma Takebayashi

Hiroshi Yamada

Yasuo Kamada

Daisuke Inoue

Akinori Saitoh

Junichi Awamura

Masahiro Yukikawa

Takamasa Hase

Teppei Kawata

Naohiro Watanabe

Ryota Inoue

Takahiro Honda

Shingo Sakashita

Masahiro Ohmori

Tsuneyasu Nagatomo

Ryohei Matsuda

Masana Shiba

Rintaro Takahashi

Hidetaka Kubo

Tomoki Murayama

Daichi Hisakuni

Ryuuta Yoshida

Tomomi Harashima

Yoshitsugu Kimura

Tsukiko Takahashi

The present disclosure provides a toner having excellent low-temperature fixing, heat-resistant-storage property, cleaning performance, and filming resistance. A toner containing toner base particles having a crystalline polyester resin and an amorphous polyester resin includes a plurality of organic particles disposed at least partially embedded in a surface of the toner base particles. A percentage of the crystalline polyester resin occupying the surface of the toner base particles is 4% to 20%, a volume average particle size of the organic particles is 10 nm to 40 nm, and a standard deviation of a distance between adjacent particles of the organic particles that are not in contact is 500 nm or less.

Toner, developing agent, toner stored unit, and image forming apparatus

A toner includes toner base particles and external additives deposited on a surface of the toner base particle. The toner base particle includes an amorphous polyester resin, a crystalline polyester resin, a release agent, and resin particles. An abundance ratio of the crystalline polyester resin in the surface of the toner base particle as observed by TEM is 2.5% or greater but 25% or less. The resin particles are deposited at the surface of the toner base particle as observed by SEM. A ratio of aggregates of the resin particles occupying the surface of the toner base particle is 1% or greater but 70% or less, where R is a major axis of the minimum particle of the resin particles, and the resin particle having a major axis of 3R or greater is determined as the aggregate.

Toner, developer, toner storage unit, image forming apparatus, and image forming method

A toner includes toner particles, each including: a toner base particle including a binder resin, a colorant, and wax; and resin particles on a surface of the toner base particle, wherein Formulae 1 to 3 below are satisfied, where M is a volume average primary particle diameter (nm) of the resin particles, and L is a distance (nm) between the resin particles present next to one another on the surface of the toner base particle:  (Formula 1)5 (nm)<≤60 (nm); and  (Formula 2)0.40≤[(nm)/(nm)]<0.90.  (Formula 3)

Toner and production method thereof, and toner stored unit, image forming apparatus, and image forming method

A toner includes toner base particles each including: a binder resin, a colorant, and wax; and resin particles on surfaces of the toner base particles. A standard deviation of a distance between the resin particles next to each other on the surfaces of the toner base particles is less than 500 nm.

Toner and production method thereof, toner stored unit, image forming apparatus, and image forming method

Provided is a toner including toner base particles and resin particles. Each toner base particle includes a binder resin, a colorant, and wax. Each resin particle e has a core-shell structure including a core and a shell, where a glass transition temperature TgA of the shell is higher than a glass transition temperature TgB of the core. A surface of each toner base particle is covered with the resin particles. A storage elastic modulus G'1 of the toner at 70° C. during heating is 1.0×10Pa or greater but 1.0×10Pa or less, and a storage elastic modulus G′2 of the toner at 100° C. during heating is 1.0×10Pa or greater but 5.0×10Pa or less, as the toner is measured by a rheometer.

A toner is provided. The toner comprises colored particles and external additives present on surfaces of the colored particles. The colored particles each comprise a core and a shell layer. The core contains a crystalline resin, a non-crystalline resin, and a colorant. The shell layer contains a resin and has a thickness of from 30 to 130 nm. The external additives comprise a metal oxide and a silicon compound. An electronegativity X(A) of the metal oxide and an electronegativity X(Si) of the silicon compound satisfy a relation 0.5&#x2264;X(A)/X(Si)&#x2264;0.8. A proportion of an amount of the metal oxide directly adhered to the surfaces of the colored particles to a total amount of the metal oxide present on the colored particles is from 60% to 90% by mass.

Toner, method for manufacturing toner, developer, toner accommodating unit, image forming apparatus, and image forming method

Provided is an image forming apparatus including an image bearer, a developing unit configured to develop with a toner, an intermediate transfer member, and a transferring unit, wherein the intermediate transfer member is a laminate including a base layer and an elastic layer including particles at a surface thereof to form convex-concave shapes at the surface, the particles have volume resistivity of from 1&#xd7;10ohm*cm through 1&#xd7;10ohm*cm, the toner includes additive, an amount of the additive separated from the toner is from 20 percent by mass through 35 percent by mass relative to a total amount of the additive in the toner when a toner dispersion liquid in which the toner is dispersed in a dispersant is irradiated with ultrasonic wave vibration with an irradiation energy dose of 4 kJ, and the toner has a dielectric constant of 2.6 or greater but 3.9 or less.

Image forming apparatus and image forming method

A fixing method is provided including the step of fixing a toner on a recording medium with a fixing device. The toner has a binder resin, a colorant, and a release agent, and has a release agent amount indicator of from 0.01 to 0.20. The release agent amount indicator is represented by a ratio (P/P) of an intensity (P) at a wave number of 2,850 cmto an intensity (P) at a wave number of 828 cmof the toner measured by a Fourier transform infrared spectroscopy attenuated total reflection method. The fixing device includes a fixing rotator driven to rotate by a driving source, a pressure rotator driven to rotate by rotation of the fixing rotator, a fixing belt interposed between the fixing rotator and the pressure rotator, and a heater to heat the fixing belt.

Fixing method, image forming method, and image forming apparatus

A toner comprising a binder resin and a release agent, wherein the toner has a difference of 30 or less between a maximum value and a minimum value among peak intensities in a range of Molecular weight M&#xb1;300 where Molecular weight M is a molecular weight selected from a range of from 300 through 5,000 in a molecular weight distribution of tetrahydrofuran (THF)-soluble components in the toner as measured by gel permeation chromatography (GPC), and wherein the peak intensities are defined as relative values assuming a maximum peak value in molecular weights of 20,000 or less is 100, in a molecular weight distribution curve taking an intensity as a vertical axis and a molecular weight as a horizontal axis as measured by GPC.

Toner, toner stored unit, and image forming apparatus

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Shizuoka, Japan

Akio Takei