Konica Minolta Business Technologies, Inc.

Minolta Camera Kabushiki Kaisha

Minolta Company, Ltd.

Konica Minolta, Inc.

Minolta Camera Co., Ltd. Senri Center

Toshiya Natsuhara

Shigeo Uetake

Junya Hirayama

Takeshi Maeyama

Makiko Watanabe

Yuji Enoguchi

Hiroshi Mizuno

Nofumi Mizumoto

Masashi Yamamoto

Masahiko Matsuura

Yuji Kamoda

Yasuhiro Ohno

Izumi Osawa

Isao Doi

Ken Tanino

Eiji Tabata

Masahiro Anno

Hideo Hotomi

Akihito Ikegawa

Keiko Momotani

Toshimitsu Fujiwara

Masaki Asano

Takamasa Ueda

Satoshi Deishi

Junji Machida

Yuji Nagatomo

Hiroshi Murasaki

Eiichi Sano

Yoshihiro Fukuhata

Kazuyoshi Hara

Masayasu Haga

Yasuo Tanaka

Masaharu Kanazawa

Fumio Masuda

Hirofumi Nakagawa

Masami Miyazaki

Hideaki Hirahara

Masakazu Takahashi

Masasi Yamamoto

Hideo Yamaki

Masami Matsuura

Tomoo Izumi

Yuuji Enoguchi

An image forming device includes: an endless intermediate transfer belt; and a secondary transferrer, wherein the secondary transferrer includes a secondary transfer roller and a counter roller, a value calculated from w/Vis defined as a nip time N [sec], when the secondary transferrer is deemed as an equivalent circuit including a resistance R1 [&#x3a9;&#xb7;m] of the secondary transfer roller, a resistance R2 [&#x3a9;&#xb7;m] of the intermediate transfer belt, a resistance R3 [&#x3a9;&#xb7;m] of the counter roller, and capacitance C[F/m] of a recording medium, in a case where a combined resistance in the equivalent circuit is defined as R[&#x3a9;&#xb7;m], and combined capacitance in the equivalent circuit is defined as C[F/m], a value calculated from R&#xd7;Cis defined as a time constant &#x3c4; [sec], and the image forming device further includes: a sheet detector; and a hardware processor.

Image forming device

Prevention of an image defect due to discharging in a transfer portion and ensured transfer efficiency are both achieved. A control electrode is in contact with an outer circumferential surface of a secondary transfer roller on an upstream side of a position of contact between the secondary transfer roller and a recording medium in a direction of rotation of the secondary transfer roller. The control electrode has a potential set to a repel a toner image with respect to the secondary transfer roller. The control electrode is in contact with the outer circumferential surface of the secondary transfer roller under such a condition that discharging occurs in a gap between the secondary transfer roller and the intermediate transfer belt and a discharging current flows through the recording medium.

Control electrode for image formation apparatus

A transfer belt includes: an elastic layer, wherein the transfer belt is used to transfer a toner image onto a recording medium, the toner image being carried on a first main surface which is one of a pair of main exposed surfaces including the first main surface and a second main surface, when, using a lower block and an upper block, the transfer belt is placed on an upper surface of the lower block, a part of the transfer belt is interposed between a curved convex surface and a curved concave surface, and a pressed region reaches a pressing force of 200 [kPa] and is constantly pressed by the pressing force, if 'a' represents a maximum value of displacement of a measurement region, and 'b' represents displacement of the measurement region after convergence, E [&#x2212;] calculated by (a&#x2212;b)/b satisfies a condition of 0.2&#x2264;E&#x2264;3.

Transfer belt and image forming device

A transfer belt transfers a toner image carried on a first main surface to a recording medium. When the transfer belt is pressed by using a lower block provided with a hole and an upper block with pressurization force increased at a prescribed rate and thereafter kept constant, E [-] and t0 are curve-fitted to a function E=&#x3b1;&#xd7;exp(&#x2212;t0/&#x3c4;) defined by a time constant &#x3c4; [s] with respect to an amount of displacement of the transfer belt and a constant &#x3b1; [-], where E [-] is calculated as (a&#x2212;b)/b, a [&#x3bc;m] represents a maximum value of an amount of displacement of a measurement region, b [&#x3bc;m] represents an amount of displacement of the measurement region after converged, and t0 [s] represents a time period from start of pressurization until the maximum pressurization force, and time constant &#x3c4; satisfies a condition of 0.015&#x2264;&#x3c4;&#x2264;0.1.

Transfer belt and image formation apparatus

A transfer belt is configured to transfer a toner image carried on a first main surface of the transfer belt to a recording medium. When the transfer belt is pressed with pressure application three increased at a predetermined pressure application rate and is then pressed with certain pressure application force by using a lower block provided with a hole and an upper block, k[&#x3bc;m/s] satisfies 6&#x2264;k&#x2264;30, k[&#x3bc;m/s] being determined by (a&#x2212;b)/{2&#xd7;(t&#x2212;t)}, where a [&#x3bc;m/s] represents a maximum value of a displacement amount of a measurement region that is a portion of the first main surface corresponding to the hole, b [&#x3bc;m] represents a convergence value thereof, t[s] represents a time when the maximum value is observed, and t[s] represents a time when the displacement amount reaches (a+b)/2 again after the maximum value is observed.

Transfer belt and image forming apparatus

A wet-type image formation apparatus includes: an intermediate transfer body that carries a toner image including toner particles, which are charged to have a first polarity, and a carrier liquid; a transferring roller that transfers a toner image onto a transfer surface of a recording medium; a charging device that charges the transfer surface to have a second polarity opposite to the first polarity; and a fixing mechanism that fixes the toner image. The fixing mechanism includes a noncontact heating device. The noncontact heating device forms the toner particles into a film such that the toner particles and the carrier liquid are separated from each other by heating the toner image when the toner particles charged to the first polarity is electrostatically adsorbed onto the transfer surface charged to have the second polarity. The film of the toner particles is fixed onto the transfer surface.

Wet-type image formation apparatus and a charging device for charging a recording medium, and method

An image forming apparatus includes a noncontact heating device, a pressurizing and heating mechanism, and a control unit. The control unit switches an operation of the pressurizing and heating mechanism based on gloss level information of a recording medium. According to the image forming apparatus, assuming that a temperature of the recording medium after noncontact heating is T1, a temperature of the recording medium after pressurizing and heating is T2 and a toner concentration after noncontact heating is Tc1 when the gloss level information shows high gloss, and assuming that a temperature of the recording medium after noncontact heating is T3 and a toner concentration after noncontact heating is Tc2 when the gloss level information shows low gloss, the conditions of T1&#x3c;T2, T1&#x3c;T3, and Tc1&#x3c;Tc2 are satisfied.

Image forming apparatus and image forming method for forming an image on recording media with different gloss levels

An infiltration amount measuring unit is provided to measure the amount of carrier liquid infiltrated in recording paper. An output signal of the infiltration amount measuring unit is input to a control device to be used to calculate a voltage supplied to a heat source (heater) in a pre-fixing unit. A signal of a paper temperature measuring unit is input to the control device, which determines whether a target temperature is reached. The control device estimates the amount of carrier liquid in a toner layer based on the information from the infiltration amount measuring unit. Then, the pre-fixing unit is controlled such that the amount of carrier liquid in the toner layer falls within an appropriate range, based on the estimation result of the amount of carrier liquid.

Wet-type image forming apparatus with adjusting device to adjust amount of carrier liquid contained in toner image

An image forming apparatus includes a fixing device for heating and pressing a toner image on a recording medium, a non-contact heating device arranged downstream of the fixing device for heating the toner image without coming into contact with the toner image, and a pressure contact device arranged downstream of the non-contact heating device and having a smooth surface. The pressure contact device has first and second arrangement states switched according to the kind of the recording medium. In the first arrangement state, the pressure contact device is arranged so as to make pressure contact with the toner image. In the second arrangement state, the pressure contact device is arranged so as not to make pressure contact with the toner image.

Image forming apparatus controlling for glossiness

A development apparatus and an image forming apparatus wherein optical high-precision detection of the toner amount of a toner layer formed on a toner carrying member is ensured even when the great amount of the toner is deposited on the toner carrying member by transferring all or a part of the toner on the surface of the toner carrying member onto a detecting roller, and wherein stable images are provided at all times.

Development apparatus and image forming apparatus using the same

An image forming apparatus for forming an image on a recording medium includes a fixing unit configured to fix on a recording medium, a toner image formed on the recording medium, through heating and pressurization and a gloss control unit configured to lower gloss of a surface of the toner image by charging the surface of the toner image fixed onto the recording medium and heating the toner image such that toner contained in the toner image reaches a softening point or higher thereof.

Image forming apparatus and gloss control method

A wet-type image forming apparatus includes: a heating unit configured to heat a recording medium and to volatilize liquid carrier in a toner image; a fixing unit configured to fix the toner image on the recording medium and disposed at a downstream side of the heating unit in a conveyance direction of the recording medium; a conveyance unit configured to convey the recording medium from the heating unit to the fixing unit; and a housing disposed to cover the conveyance unit, wherein the recording medium is conveyed on the conveyance unit in the housing toward the fixing unit after heated by the heating unit, in the presence of gas containing the volatilized liquid carrier, and the volatilized liquid carrier is cooled and turned into fine mist liquid carrier and then the fine mist liquid carrier attaches to the recording medium before the recording medium reaches the fixing unit.

Wet-type image forming apparatus

Provided is a deposited-toner measuring apparatus capable of accurate detection of the amount of toner deposited on the toner carrying member, and an image forming apparatus equipped with the aforementioned measuring apparatus and capable of controlling the amount of toner deposited on the toner carrying member to a desired level so as to provide stable image quality at all times. A deposited-toner measuring apparatus that removes a toner layer in a part of the surface of the toner carrying member, detects change in the capacitance at the portion with a toner layer and the portion without such a toner layer, and detects the amount of the deposited toner based on the detection result of the said change in the capacitance.

Deposited toner measuring apparatus having a capacitor and a capacitance change detector for detecting a change in capacitance of the capacitor, and an image formation apparatus, and method for controlling image formation apparatus related thereto

A developer device includes two developer rollers arranged opposite to an image carrier. A first developer bias voltage (waveform Z) of a rectangular waveform obtained by superimposing an AC voltage on a DC voltage is applied to one of the developer rollers. A second developer bias voltage (waveform A) obtained by superimposing an AC voltage on a DC voltage is applied to the other developer roller. The waveform A is a waveform obtained by deforming the rectangular wave in the first developer bias voltage such that toner adhered to the image carrier is prevented from being dislodged by toner being subsequently scattered. According to the developer device, an optimal image density can be obtained at a low-density potential.

Developer device and image forming apparatus

Provided is a development device and an image forming apparatus that realize high image quality with improved decrease in density at high speed development and with reduced occurrence of development hysteresis (ghost) in a hybrid developing method having a plurality of toner carriers, by reducing the decrease in the toner supplying ability to a downstream-side toner carrier, which decrease is caused by the supply of toner to an upstream-side toner carrier on an upstream side in a rotating direction of a developer carrier. By providing a magnetic pole between main magnetic poles, of the developer carrier, facing the toner carriers, a magnetically raised bristle of developer is moved by a magnetic force, while the developer in which development hysteresis due to supplying toner to the upstream-side toner carrier occurred is conveyed to supply toner to the downstream-side toner carrier, whereby a developer layer is stirred.

Development device having developer carrier with stationary disposed magnetic body

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Takarazuka, Japan

Toshiya Natsuhara