Canon Kabushiki Kaisha

Hiroyuki Tomono

Nobuhiro Nakamura

Jun Kamatani

Masashi Hashimoto

Masato Tanaka

Atsushi Okuda

Kunihiko Sekido

Yuka Ishiduka

Michiyo Sekiya

Atsushi Fujii

Kengo Kishino

Daisuke Miura

Takeshi Murakami

Akihito Saitoh

Katsuhisa Yamazaki

Tetsuya Kosuge

Kenichi Kaku

Harunobu Ogaki

Yoshitaka Suzumura

Naoki Yamada

Satoshi Igawa

Kazuhiro Yamauchi

Masataka Kawahara

Daisuke Yoshiba

Keiji Okinaka

Takashi Matsui

Akihiro Senoo

Koji Nishikawa

Hironobu Iwawaki

Kazunori Noguchi

Hiroki Ohrui

Shuntaro Watanabe

Yota Ito

Takashi Anezaki

Haruyuki Tsuji

Shuhei Moribe

Shotaro Nomura

Kazuhisa Shida

Hideaki Matsuoka

Atsuhiko Ohmori

Tatsuya Saeki

Takuya Mizuguchi

Osamu Matsushita

Kosuke Fukudome

Kazumichi Sugiyama

Akihiro Maruyama

Chiaki Nishiura

Sho Kimura

Masahiro Kurachi

Tatsuya Yamaai

Isao Kawata

Shoma Hinata

Hirotoshi Uesugi

Hirofumi Kumoi

Takayuki Horiuchi

Hiroki Akiyama

Masanori Muratsubaki

Chika Negishi

Shunsuke Matsushita

Issei Imamura

Tomonari Horikiri

Hiroki Kagawa

Yuko Chishina

A toner comprising a toner particle comprising a binder resin and a crystalline resin, wherein the binder resin comprises an amorphous resin, when the toner is measured with a temperature-modulated differential scanning calorimeter, at least one endothermic peak derived from the crystalline resin is present in a temperature range from 55.0&#xb0; C. to 95.0&#xb0; C. in a total heat flow; and a ratio of an endothermic quantity of the endothermic peak in a reversing heat flow to an endothermic quantity of the endothermic peak in the total heat flow is 50.0% or more, a glass transition temperature Tg1st obtained in the reversing heat flow in a first temperature rise and a glass transition temperature Tg2nd obtained in a reversing heat flow in a second temperature rise satisfy Tg1st&#x2212;Tg2nd&#x2265;7.0&#xb0; C.

Toner

An electrophotographic apparatus comprising an electrophotographic photosensitive member, a charging device and a developing device, wherein the charging device comprises a conductive member arranged to be capable of contacting the electrophotographic photosensitive member, the conductive layer at the outer surface of the conductive member comprises a matrix and a plurality of domains dispersed in the matrix, at least some of the domains are exposed at the outer surface of the conductive member, the matrix has a volume resistivity R1 of larger than 1.00&#xd7;10&#x3a9;&#xb7;cm, the volume resistivity R1 of the matrix is 1.0&#xd7;10times or more a volume resistivity R2 of the domains, the developing device comprises the toner comprising a toner particle and a silica fine particle, and a coverage ratio of the toner surface with the silica fine particles is from 62.0% by area to 100.0% by area as determined by X-ray photoelectron spectroscopy.

Electrophotographic apparatus, process cartridge and cartridge set

An electrophotographic apparatus comprising an electrophotographic photosensitive member, a charging device and a developing device, wherein the charging device comprises a conductive member arranged to be capable of contacting the electrophotographic photosensitive member, a conductive layer of the conductive member comprises a matrix domain structure, at least a part of the domains Dt is exposed at the conductive member outer surface, the matrix has a volume resistivity R1 of larger than 1.00&#xd7;10&#x3a9;&#xb7;cm, the domains Dt has a volume resistivity of smaller than R1, the developing device comprises the toner, domains Dc formed of the crystalline material exist in a cross section of the toner, distances between adjacent wall surfaces of the domains Dc is from 30 to 1,100 nm, and a weight-average particle diameter D4 of the toner and distances Dms between adjacent wall surfaces between the domains Dt satisfies D4&#x2265;Dms.

Electrophotographic apparatus, process cartridge, and cartridge set

A toner including a toner particle containing a binder resin, wherein the binder resin contains a crystalline resin, and in viscoelasticity measurement of the toner with Tp being a peak temperature of an endothermic peak derived from the crystalline resin in DSC of the toner, given G'(Tp&#x2212;5, 0.01 Hz) as a storage modulus at a temperature of Tp&#x2212;5&#xb0; C. and a frequency of 0.01 Hz, G&#x2032;(Tp&#x2212;5, 10 Hz) as a storage modulus at a temperature of Tp&#x2212;5&#xb0; C. and a frequency of 10 Hz, and G&#x2032;(Tp&#x2212;30, 10 Hz) as a storage modulus at a temperature of Tp&#x2212;30&#xb0; C. and a frequency of 10 Hz, the following formulae are satisfied:&#x2032;(&#x2212;30,10 Hz)/&#x2032;(&#x2212;5,0.01 Hz)&#x2264;1.40&#x2032;(&#x2212;5,10 Hz)/&#x2032;(&#x2212;5,0.01 Hz)&#x2264;2.20.

A toner comprising a toner particle containing a resin and a colorant, wherein, with respect to a temperature-storage elastic modulus curve obtained by powder dynamic viscoelastic measurement on the toner, (I) the relative minimum values for the variation in the storage elastic modulus E' with respect to temperature T in the temperature range of at least 30&#xb0; C. and not more than 180&#xb0; C. have a relative minimum value of equal to or less than &#x2212;1.00&#xd7;10and the relative minimum value on the lowest temperature side is equal to or less than &#x2212;1.00&#xd7;10; (II) the storage elastic modulus E&#x2032; (50) of the toner at 50&#xb0; C. is at least 1.00&#xd7;10and not more than 9.00&#xd7;10; and (III) for a storage elastic modulus E&#x2032; (120) of the toner at 120&#xb0; C., E&#x2032; (50) and E&#x2032; (120) satisfy 1.50&#x2264;[E&#x2032; (50)]/[E&#x2032; (120)]&#x2264;3.00.

Provided is a toner having a toner particle including a binder resin and a colorant, wherein the toner has a softening point of at least 100&#xb0; C. and not more than 150&#xb0; C., and when Tgt represents a glass transition temperature (&#xb0; C.) of the toner during a second temperature rise as measured with a DSC, Tgf represents a glass transition temperature (&#xb0; C.) of a tetrahydrofuran-insoluble matter of the binder resin during a second temperature rise as measured with a DSC, and Tgk represents a glass transition temperature (&#xb0; C.) of a tetrahydrofuran-soluble matter of the binder resin during a second temperature rise as measured with a DSC, the toner satisfies Tgt&#x3e;Tgf (1), Tgt&#x3e;Tgk (2), and 35&#xb0; C.&#x2264;Tgf&#x2264;70&#xb0; C. (3).

A toner comprising: a toner particle containing a binder resin and a colorant; and an external additive, wherein the external additive is a composite particle having an organic substance and an organosilicon polymer coating layer on the surface of the organic substance, and when a curve for the variation (dE'/dT) in the storage elastic modulus E&#x2032; of the toner with respect to temperature T [&#xb0; C.] is obtained on the basis of a curve of the temperature T&#x2014;the storage elastic modulus E&#x2032; [Pa] of the toner, as determined by powder dynamic viscoelasticity measurements of the toner, the relative minimum value on the lowest temperature side between the onset temperature and 90&#xb0; C. is &#x2212;1.35&#xd7;10or less.

Toner, and external additive for toner

An electrophotographic photosensitive member has a support, a charge generation layer, and a charge transport layer in this order, the charge transport layer containing a charge transport material. The charge transport layer is a surface layer of the electrophotographic photosensitive member and contains a polycarbonate resin having a structural unit selected from group A and a structural unit selected from group B.  

Electrophotographic photosensitive member, method for manufacturing electrophotographic photosensitive member, process cartridge, and electrophotographic apparatus

A process cartridge includes an electrophotographic photosensitive member and a gap retaining member, where the electrophotographic photosensitive member includes a first region having an undercoat layer, a charge generating layer, and a charge transporting layer on a support in this order and a second region having an undercoat layer and a charge transporting layer on a support in this order, the undercoat layer contains a metal oxide particle and any one of an urethane resin, an amino resin, and a polyamide resin as a binder resin, and the charge transporting layer contains a charge transporting substance and at least one selected from the group consisting of a polycarbonate resin and a polyester resin, and where the gap retaining member comes into contact with a surface of the second region of the electrophotographic photosensitive member.

Electrophotographic photosensitive member, process cartridge, and electrophotographic apparatus

Provided is an electrophotographic apparatus, including an electrophotographic photosensitive member, a charging unit arranged in a non-abutment manner with respect to the electrophotographic photosensitive member, a cleaning unit or a developing unit arranged in abutment against the electrophotographic photosensitive member, and a transferring unit.

Electrophotographic apparatus and process cartridge

An electrophotographic photosensitive member has a support, a charge generation layer, and a charge transport layer in this order, the charge transport layer containing a charge transport material. The charge transport layer is a surface layer of the electrophotographic photosensitive member and contains a polycarbonate resin having a structural unit selected from group A and a structural unit selected from group B (groups A and B defined in the disclosure).

A conductive layer of an electrophotographic photosensitive member includes a binder material, a first metal oxide particle, and a second metal oxide particle. The first metal oxide particle is a zinc oxide particle or tin oxide particle coated with tin oxide doped with phosphorus, tungsten, niobium, tantalum, or fluorine. The second metal oxide particle is an uncoated zinc oxide particle or tin oxide particle. The content of the first metal oxide particle is not less than 20% by volume and not more than 50% by volume based on the total volume of the conductive layer. The content of the second metal oxide particle is not less than 0.1% by volume and not more than 15% by volume based on the total volume of the conductive layer, and not less than 0.5% by volume and not more than 30% by volume based on the content of the first metal oxide particle.

An undercoat layer of an electrophotographic photosensitive member includes a product having electron transportability and a particle including titanium oxide, and a surface layer of the electrophotographic photosensitive member includes a product of a composition including a hole transporting substance having a polymerizable functional group and a photopolymerization initiator.

Electrophotographic photosensitive member, method for producing the same, process cartridge, and electrophotographic apparatus

A conductive layer of an electrophotographic photosensitive member contains a first metal oxide particle, a second metal oxide particle, and a binder material. The first metal oxide particle is a zinc oxide particle or tin oxide particle coated with tin oxide doped with phosphorus, tungsten, fluorine, niobium, or tantalum, and the second metal oxide particle is a tin oxide particle doped with an element selected from the group consisting of phosphorus, tungsten, fluorine, niobium, and tantalum, the element being the same as the element with which the tin oxide of the first metal oxide particle is doped. The conductive layer satisfies formulae (1) and (2)2&#x2266;{()/()}&#xd7;100&#x2266;25&#x2003;&#x2003;formulae (1):15&#x2266;{()+()}&#xd7;100&#x2266;45&#x2003;&#x2003;formulae (2).

An electrophotographic apparatus includes an electrophotographic photosensitive member, a charging unit, and a transfer unit and satisfies the following formulae (1) to (3):L&#x3c;L&#x2003;&#x2003;(1)L&#x3e;L&#x2003;&#x2003;(2)L&#x3e;L&#x2003;&#x2003;(3)

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Numazu, Japan

Hiroyuki Tomono