Canon Kabushiki Kaisha

Kosuke Fukudome

Tetsuya Kinumatsu

Shuhei Moribe

Koji Nishikawa

Katsuhisa Yamazaki

Daisuke Yoshiba

Shotaro Nomura

Kunihiko Nakamura

Tetsuya Ida

Yoshiaki Shiotari

Satoshi Mita

Tomohiro Unno

Yojiro Hotta

Kozue Uratani

Yuta Komiya

Hiroyuki Fujikawa

Takayuki Itakura

Nozomu Komatsu

Naoki Okamoto

Shohei Tsuda

Hiroki Akiyama

Atsuhiko Ohmori

Kazuo Terauchi

Takuya Mizuguchi

Ryo Nagata

Mariko Yamashita

Yusuke Hasegawa

Noriyoshi Umeda

Takaaki Furui

Dai Nozaki

Sho Kimura

Kazuhiro Yamauchi

Kenta Kamikura

Hiroyuki Tomono

Masahiro Kurachi

Tatsuya Saeki

Takashi Matsui

Keisuke Tanaka

Hironori Minagawa

Koh Ishigami

Tomohisa Sano

Yoshitaka Suzumura

Kentaro Kamae

Motonari Ito

Yuujirou Nagashima

Kenji Ookubo

Takuma Ikejiri

Tomoko Sugita

The present disclosure provides a toner that achieves both high image gloss and high image loadability. The toner includes a toner particle that includes: a styrene-acrylic resin having a unit represented by the formula (1); and an ester compound A, wherein the ester compound A is an ester compound represented by the formula (2) or the formula (3): and an absolute value of a difference between SPb (J/cm)that is an SP value of the styrene-acrylic resin and SPw1 (J/cm)that is an SP value of the ester compound A is 1.00 or larger and 2.00 or smaller.

Toner

A toner including a toner particle containing a binder resin and an ester compound, wherein the binder resin contains a styrene-acrylic-based resin, the styrene-acrylic-based resin contains a specific unit, the ester compound has a specific structure, and a molar ratio of the specific unit to the ester compound is 0.5 to 1.5.

A toner comprising a toner particle comprising a binder resin, and an ester wax A having a specific structure, wherein in a diffraction spectrum obtained by an X-ray diffractometer after the toner has been allowed to stand at 120° C. for 5 minutes and then at 60° C. for 5 minutes, assuming that a spectrum having a maximum peak in a range where 2θ is from 5.45° to 5.95° is P1 and an integrated intensity of the P1 is S1, and a spectrum having a maximum peak in a range where 2θ is from 21.45° to 21.95° is P2 and an integrated intensity of the P2 is S2, relationships of formulas (2) and (3) below are satisfied.1/2≤0.25  (2)2≥1000  (3)

An electrophotographic apparatus having an electrophotographic photosensitive member, a charging unit, and a developing unit for forming a toner image on a surface of the electrophotographic photosensitive member, wherein the charging unit has a conductive member disposed to be contactable with the electrophotographic photosensitive member; a conductive layer at the surface of the conductive member has a matrix and a plurality of domains dispersed in the matrix; at least a portion of the domains is exposed at the outer surface of the conductive member; the outer surface of the conductive member is constituted of at least the matrix and the domains; a volume resistivity R1 of the matrix is greater than 1.00&#xd7;10&#x3a9;&#xb7;cm; a volume resistivity R2 of the domains is smaller than R1; the developing unit contains the toner; and a dielectric loss tangent of the toner is at least 0.0027.

Electrophotographic apparatus, process cartridge, and cartridge set

An electrophotographic apparatus having an electrophotographic photosensitive member, a charging unit, and a developing unit for forming a toner image, wherein the charging unit has a conductive member disposed to be contactable with the electrophotographic photosensitive member, a conductive layer at the surface of the conductive member has a matrix-domain structure, at least a portion of the domains is exposed at the outer surface of the conductive member, the outer surface of the conductive member is constituted at least of the matrix and these domains, a volume resistivity R1 of the matrix is greater than 1.00&#xd7;10&#x3a9;&#xb7;cm, a volume resistivity R2 of the domains is less than R1, Martens hardness G1 of the matrix and Martens hardness G2 of the domains satisfy a prescribed relationship, and an onset temperature T(A) for a storage elastic modulus E' of the toner is not more than 80.0&#xb0; C.

A toner containing a toner particle that contains a binder resin and a crystalline material, wherein, in measurement of powder dynamic viscoelasticity of the toner, when T(A)&#xb0; C. is taken as an onset temperature for a storage elastic modulus E' obtained at a ramp rate of 20&#xb0; C./min, EA&#x2032;(100) Pa is taken as a storage elastic modulus at 100&#xb0; C. obtained at a ramp rate of 20&#xb0; C./min, and T(B)&#xb0; C. is taken as an onset temperature for a storage elastic modulus E&#x2032; obtained at a ramp rate of 5&#xb0; C./min, T(A)&#x2212;T(B) is 3.0&#xb0; C. or less, T(A) is from 45.0&#xb0; C. to 70.0&#xb0; C., and EA&#x2032;(100) is from 4.0&#xd7;10Pa to 6.5&#xd7;10Pa.

A toner comprising a toner particle including a binder resin and a magnetic body, wherein in cross-sectional observation of the toner with a transmission electron microscope, where an area percentage occupied by the magnetic body in a region of 200 nm or less from a contour of a cross section of the toner particle to a centroid of the cross section is taken as A1, and an area percentage occupied by the magnetic body in a region of from 200 nm to 400 nm from the contour of the cross section of the toner particle to the centroid of the cross section is taken as A2, the area percentage A1 is from 38% to 85%, the area percentage A2 is from 0% to 37%, and a ratio A2/A1 of the area percentage A2 to the area percentage A1 is from 0 to 0.75.

A toner including a toner particle including a binder resin and a crystalline material, wherein in powder dynamic viscoelasticity measurement of the toner, where an onset temperature of a storage elastic modulus E' obtained when a temperature is raised at 20&#xb0; C./min is denoted by T(A)&#xb0; C., and an onset temperature of a storage elastic modulus E&#x2032; obtained when a temperature is raised at 5&#xb0; C./min is denoted by T(B)&#xb0; C., T(A)&#x2212;T(B) is 3.0&#xb0; C. or less, in DSC of the toner, a peak temperature of a maximum endothermic peak is from 50.0&#xb0; C. to 90.0&#xb0; C., and an amount of a tetrahydrofuran-insoluble component in the binder resin is from 15% by mass to 60% by mass.

A toner comprising a toner particle including a binder resin, wherein the toner is such that (1) when a powder dynamic viscoelasticity measurement method is used, a measurement start temperature is set to 25&#xb0; C., and a ramp rate is set to 20&#xb0; C./min, on a curve of a storage elastic modulus E' (Pa) where a temperature (&#xb0; C.) is plotted against an abscissa and the storage elastic modulus E&#x2032; is plotted against an ordinate, a temperature at a time when the E&#x2032; at a start of a measurement has decreased by 50% is from 60&#xb0; C. to 90&#xb0; C., and (2) a load at a yield point of a displacement-load curve which is determined by a nanoindentation method and where a load (mN) is plotted against an ordinate and a displacement amount (&#x3bc;m) is plotted against an abscissa, is 0.80 mN or more; and a method for producing thereof.

Toner and method for producing toner

A toner including: a toner particle that includes a binder resin; and an external additive, wherein a toner hardness A N/m and a toner hardness B N/m satisfy B&#x2265;600 and B/A&#x2265;1.30, in the formulas, the toner hardness A is an average value of a slope in a displacement region of from 0.00 &#x3bc;m to 0.20 &#x3bc;m when measuring the toner under a condition of a load application speed of 0.83 &#x3bc;N/sec, and the toner hardness B is an average value of a slope in a displacement region of from 0.00 &#x3bc;m to 0.20 &#x3bc;m when measuring the toner under a condition of a load application speed of 2.50 &#x3bc;N/sec.

A toner including: a toner particle that includes a binder resin and a crystalline material, wherein the binder resin includes a vinyl resin having an ether structure, and where intensities of secondary ion mass/secondary ion charge number (m/z) of 59, 44, and 135 are denoted by A (ppm), B (ppm), and C (ppm), respectively, in a measurement of the toner by time-of-flight secondary ion mass spectrometry, the intensities at 100 nm from the surface of the toner satisfy the relationships of the following formulas (1) and (2):/()&#x2264;1.00&#x2003;&#x2003;(1)()&#x2265;2000&#x2003;&#x2003;(2).

A magnetic toner comprising a magnetic toner particle including a binder resin, a magnetic body and a crystalline polyester, wherein a storage elastic modulus E'(40) [Pa] at 40&#xb0; C. and a storage elastic modulus E&#x2032;(85) [Pa] at 85&#xb0; C., which are obtained in a powder dynamic viscoelasticity measurement of the magnetic toner, satisfy the following formulas (1) to (3).&#x2032;(40)&#x2265;6.0&#xd7;10&#x2003;&#x2003;(1)&#x2032;(85)&#x2264;5.5&#xd7;10&#x2003;&#x2003;(2)[&#x2032;(40)&#x2212;&#x2032;(85)]&#xd7;100/&#x2032;(40)&#x2265;40&#x2003;&#x2003;(3)

Magnetic toner

A magnetic toner comprising a magnetic toner particle including a binder resin, a magnetic body and a crystalline polyester, wherein the dielectric loss tangent at 100 kHz is 1.0&#xd7;10or more, a variation coefficient CV3 of an occupied area ratio of the magnetic body when a cross section of the magnetic toner particle is divided by a square grid having a side of 0.8 &#x3bc;m in cross-sectional observation of the magnetic toner particle using a transmission electron microscope TEM is from 30.0% to 80.0%, and where a storage elastic modulus of the magnetic toner at 40&#xb0; C. is taken as E'(40) [Pa] and a storage elastic modulus of the magnetic toner at 85&#xb0; C. is taken as E&#x2032;(85) [Pa], the following formulas (1) and (2) are satisfied:&#x2032;(85)&#x2264;5.5&#xd7;10&#x2003;&#x2003;(1)[&#x2032;(40)&#x2212;&#x2032;(85)]&#xd7;100/&#x2032;(40)&#x2265;30&#x2003;&#x2003;(2).

A toner comprising an external additive and a toner particle including a binder resin, a colorant and inorganic fine particles A, wherein the external additive contains an external additive B, a number average particle diameter of primary particles of the external additive B is 30 to 200 nm, an adhesion index of the external additive B to the toner particle is 0.00 to 3.00, a number average particle diameter of primary particles of the inorganic fine particles A is greater than that of the external additive B, and in SEM observations of the toner under specific condition, the number of particles (Na) of the external additive B in a 2 &#x3bc;m square region of the toner surface and the number of particles (Nb) of the external additive B observed in a state of overlapping with the inorganic fine particles A in the region satisfy Nb/Na of 0.20 or more.

A magnetic toner is provided, which has a magnetic toner particle containing a binder resin, a wax, and a magnetic body, wherein, when Dn is a number-average particle diameter of the toner, CVis coefficient of variation of a brightness variance value of the toner in a particle diameter range of Dn &#x2212;0.500 to +0.500, and CVis coefficient of variation of a brightness variance value of the toner in a particle diameter range of Dn &#x2212;1.500 to &#x2212;0.500, a relationship CV/CV&#x2264;1.00 is satisfied; an average brightness of the toner in the range of Dn &#x2212;0.500 to +0.500 is 30.0 to 60.0; and when, in a cross section of the toner observed using a transmission electron microscope, which is divided with a square grid having a side of 0.8 &#x3bc;m, coefficient of variation CVof an occupied area percentage for the magnetic body is 40.0 to 80.0%.

Growing community of inventors

Tokyo, Japan

Kosuke Fukudome