Mita Industrial Co., Ltd.

Kyocera Document Solutions Inc.

Daikin Industries, Ltd.

Takeshi Arakawa

Hidenori Asada

Masahide Inoue

Ryota Kobayashi

Naruo Yabe

Takeo Mizobe

Masanori Sugahara

Nobuyuki Tsuji

Yutaka Aso

Shigeki Yamada

Ryo Fujisawa

Toshio Tanaka

Koichi Tsuyama

Mamoru Kato

Satoshi Hara

Eisaku Okubo

Katsuyuki Teranishi

Kiyoshi Kuroi

Hiroshi Komata

Takashi Takahashi

Takayuki Sunayama

Kazuki Ono

Yuta Sasai

Yu Jiang

A toner includes toner particles. The toner particles each include a toner mother particle containing a binder resin and an external additive attached to a surface of the toner mother particle. The external additive includes fluorine-containing particles. The fluorine-containing particles include a fluorine atom at least in surface layers thereof. The amount of the fluorine-containing particles is at least 0.10 parts by mass and no greater than 0.50 parts by mass relative to 100 parts by mass of the toner mother particles. When ultrasonication is performed, a residual amount ratio of remaining fluorine-containing particles is at least 0% by mass and no greater than 20% by mass relative to the amount of the fluorine-containing particles attached to the toner mother particles before the ultrasonication.

Toner, image forming apparatus, and image formation method

A development device includes an accommodation section that accommodates a developer and a developer bearing member that carries the developer in the accommodation section. The developer bearing member includes a magnetic member and a sleeve provided around the magnetic member rotatably around the magnetic member. The sleeve includes a metal substrate with a surface having projections and recesses and a plating layer covering the surface of the metal substrate. The plating layer contains chromium and cobalt. The developer contains a toner and the toner includes toner particles. The toner particles each include a toner mother particle and external additive particles attached to the surface of the toner mother particle. The toner mother particles contain a binder resin and a magnetic powder. The external additive particles include alumina particles with surfaces that are hydrophobized.

Development device, image forming apparatus, and development method

A correcting system includes an acquisition unit, a storage unit, and a correction unit. The acquisition unit acquires information indicating first capture efficiency of a filter for first microscopic particles. The storage unit stores correction data to correct the first capture efficiency to second capture efficiency of the filter for second microscopic particles. The correction unit corrects the first capture efficiency acquired by the acquisition unit to the second capture efficiency based on the correction data.

Correcting system, and correcting method

A toner includes toner particles. The toner particles each include a toner mother particle and an external additive attached to the surface of the toner mother particle. The external additive includes specific external additive particles. The specific external additive particles have a number average primary particle diameter of at least 30 nm and no greater than 305 nm. The specific external additive particles include antimony-doped tin oxide particles or indium tin oxide particles. A ratio (M/(M+M)) of a mass (M) of an antimony atom to a total of the mass (M) of the antimony atom and a mass (M) of a tin atom in the antimony-doped tin oxide particles is at least 0.04 and no greater than 0.46.

Toner

A toner contains toner particles. The toner particles each include a toner mother particle containing a binder resin and an external additive attached to a surface of the toner mother particle. The external additive contains titanate compound particles doped with lanthanum and a group 5 element in the periodic table as external additive particles. The amount of the lanthanum is at least 1.50% by mass relative to the total mass of the titanate compound particles. The amount of the group 5 element in the periodic table is at least 0.01% by mass and no greater than 0.60% by mass relative to the total mass of the titanate compound particles.

The image forming apparatus is an image forming apparatus including an image bearing member, a developing device, a transfer device, and a cleaning device. The developing device includes a toner bearing member having a surface subjected to alumite treatment. Toner that is used in the image forming apparatus is magnetic mono-component developer including magnetic toner particles containing at least binder resin and iron-containing magnetic powder, and an external additive to be externally added to the magnetic toner particles. The external additive is formed from inorganic fine particles which have been subjected to surface treatment with a tin-containing compound and an antimony-containing compound. In the image forming apparatus, the ratio of antimony to iron of the toner that has been removed by the cleaning device is double or more the ratio of antimony to iron of the toner before being conveyed by the toner bearing member.

Image forming method using an external additive of inorganic fine particles that have been subjected to surface treatment with a tin-containing compound and an antimony-containing compound

The present invention relates to a recycle developing process which comprises developing an electrostatic image formed on a photosensitive material with a starting developer filled in a developing vessel, transferring the toner image to a predetermined paper, recovering the toner remaining on the photosensitive material by a cleaning means, and repeating the developing procedure while replenishing a virgin toner and the toner recovered by the cleaning means into the developing vessel; wherein the virgin toner to be replenished into the developing vessel is that which is fulfilled in a container wherein a rotating roller is provided in an opening portion at a lower portion has a flowability, shown as a fallen amount of the toner at a time of falling via the rotating roller for a certain fixed time, of 50 to 70% based on the toner in the starting developer. According to this process, an abrupt decrease in the properties of the developer due to the mixing of the recovered toner can be relaxed. As a result, a stable image free from fogging or toner scattering can be formed by the recycle developing process.

Recycle developing process

In a method of adjusting image forming conditions according to the present invention, it is judged whether or not a humidity detected by a humidity sensor is not less than a predetermined first humidity H.sub.1 (step W6). As a result, when it is judged that the humidity is not less than the first humidity H.sub.1, a main charger table is accessed using the detected absolute humidity as an address, and corresponding additional data G is read out (step W7). The additional data G read out, together with additional data E and main charger driving time adjustment data F, is added to main charger reference data K.sub.2, so that main charger voltage data C.sub.2 is produced (step W8). On the other hand, when the detected humidity is less than the first humidity H.sub.1, a voltage to be applied to a main charger is not adjusted depending on the humidity.

Method of adjusting image forming conditions and image forming apparatus

A recycle developing method utilizes the steps of (1) providing a developing vessel containing a starting developer composed of an electroscopic toner and a magnetic carrier; (2) transferring toner from the developing vessel to a photosensitive material having an electrostatic latent image formed thereon; (3) transferring a portion of the toner on the photosensitive material to a paper to form a toner image on the paper; (4) recovering toner remaining on the photosensitive material after the aforementioned portion of toner is transferred to the paper to form a toner image thereon; and (5) repeating steps (2)-(4) while replenishing toner in the developing vessel by the sub-steps of: (5a) supplying toner recovered in step (4) to the developing vessel, and (5b) supplying a virgin toner, having a higher chargeability than the electroscopic toner in the starting developer, to the developing vessel, to form a mixed toner in the developing vessel. An absolute value of the average charge quantity of the mixed toner is greater than the absolute value of the average charge quantity of the electroscopic toner in the starting developer plus 10 .mu.C/g. Apparatus to effect the process is also disclosed.

Recycle developing method and apparatus

The present invention provides an electrophotographic toner containing, as a fixing resin, a styrene-acrylic copolymer in which styrene content, molecular-weight distribution and acid value are specified. The electrophotographic toner of the present invention is improved in heat resistance by raising the glass transition temperature of the fixing resin, while assuring excellent low-temperature fixing properties and resistance to off-set.

Electrophotographic toner

The present invention provides an electrophotographic toner having rheology characteristics, under the conditions of measuring frequency of 1 Hz and measuring distortion of 1 degree, such that:

Electrophotographic toner having improved low temperature fixing

The present invention provides an electrophotographic toner containing, as a fixing resin, a styrene-acrylic copolymer in which styrene content and molecular-weight distribution are specified, and which contains a specific high-molecular-weight component. The electrophotographic toner of the present invention is improved in bending resistance while assuring excellent low-temperature fixing properties, resistance to off-set and heat resistance.

Disclosed is a one-component magnetic developer for the electrophotography, which comprises one-component magnetic toner particles and at least one fine particulate additive selected from the group consisting of hydrophobic silica, hydrophilic silica and alumina, wherein the one-component magnetic toner particles have a sphericity degree (DS), defined by the following formula, of 70 to 90%, and a specific surface area of 1.4 to 2.0 m.sup.2 /g:

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Osaka, Japan

Takeshi Arakawa