Patents by Inventor Noriyoshi Umeda
Noriyoshi Umeda has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).
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Patent number: 11448982Abstract: An electrophotographic apparatus including an electrophotographic photosensitive member, a charging unit, and a developing unit, wherein the charging unit includes a conductive member disposed to be contactable with the electrophotographic photosensitive member, a conductive layer of the conductive member has a matrix-domain structure, at least some of the domains are exposed at the outer surface of the conductive member, the volume resistivity RI of the matrix is greater than 1.00×1012 ?·cm and not greater than 1.00×1017 ?·cm, the matrix volume resistivity R1 is at least 1.0×105-times the domain volume resistivity R2, and the developing unit includes a toner, the toner includes a binder resin-containing toner particle and an external additive, and the external additive contains fine particles of a hydrotalcite compound.Type: GrantFiled: October 15, 2020Date of Patent: September 20, 2022Assignee: CANON KABUSHIKI KAISHAInventors: Tsuneyoshi Tominaga, Shohei Tsuda, Shohei Kototani, Noriyoshi Umeda, Masahiro Kurachi, Kazuhiro Yamauchi, Motonari Ito
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Patent number: 11320756Abstract: An electrophotographic apparatus comprising an electrophotographic photosensitive member, a charging unit, and a developing unit, wherein the charging unit has a conductive member contactable with the electrophotographic photosensitive member, and a conductive layer of the conductive member has a matrix-domain structure; at least some of the domains are exposed at the outer surface; a volume resistivity R1 of the matrix and a volume resistivity R2 of the domains satisfy specific relationship; Martens hardness G1 of the matrix and Martens hardness G2 of the domains satisfy relationship G1<G2; the surface roughness Ra of the conductive member is not more than 2.00 ?m; the toner has an external additive having a shape factor SF-1 of not more than 115; and A<Dms is satisfied where A is the number-average diameter of the external additive and Dms is a distance between adjacent walls between the domains.Type: GrantFiled: October 15, 2020Date of Patent: May 3, 2022Assignee: CANON KABUSHIKI KAISHAInventors: Shohei Kototani, Noriyoshi Umeda, Tsuneyoshi Tominaga, Shohei Tsuda, Noboru Miyagawa, Kazuhiro Yamauchi
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Patent number: 11294296Abstract: A toner comprising: a toner particle including a binder resin; and an external additive, wherein the external additive includes an external additive A which is silica fine particles and an external additive B which is a fatty acid metal salt, the external additive A has a specific particle diameter, a coverage ratio of a surface of the toner particle with the external additive A is from 60% to 80%, and where an average theoretical surface area obtained from a number average particle diameter, a particle size distribution and a true density of the toner particle is denoted by C (m2/g), an amount of the external additive B is denoted by D (parts by mass) and a coverage ratio of the surface of the toner particle with the external additive B is denoted by E (%), following formulas are satisfied: 0.05?D/C?2.00 E/(D/C)?50.0.Type: GrantFiled: June 25, 2020Date of Patent: April 5, 2022Assignee: CANON KABUSHIKI KAISHAInventors: Hidekazu Fumita, Noriyoshi Umeda, Tomonori Matsunaga, Satoshi Otsuji
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Patent number: 11112712Abstract: A toner comprising: a toner particle that contains a release agent-containing toner base particle, and an organosilicon polymer on a toner base particle surface, and an external additive A, the organosilicon polymer has a T3 unit structure; the organosilicon polymer forms protruded portions on the toner base particle surface; the number-average value of the protrusion height H is from 30 nm to 300 nm; the ratio of the number-average primary particle diameter R of the external additive A to the number-average value of the protrusion height H is from 1.00 to 4.00; the number-average primary particle diameter R of the external additive A is from 30 nm to 1,200 nm; and, in an image obtained by observing the toner surface with SEM, the area percentage for the bright region area in the image with reference to the total area of the image is from 30.0% to 75.0%.Type: GrantFiled: March 11, 2020Date of Patent: September 7, 2021Assignee: CANON KABUSHIKI KAISHAInventors: Tomonori Matsunaga, Hidekazu Fumita, Noriyoshi Umeda, Shohei Tsuda
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Patent number: 11061342Abstract: 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 on the conductive member outer surface comprises a matrix and a plurality of domains dispersed in the matrix, at least some of the domains are exposed at the conductive member outer surface, the matrix has a volume resistivity of larger than 1.00×1012 ?·cm and is 1.0×105 times or more one of the domains, the developing device comprises the toner comprising a toner particle, fine particles A and B, the fine particle A has a volume resistivity of 1.0×103 to 1.0×1010 ?·cm, and the fine particle B is silica fine particle and having a volume resistivity of 1.0×1011 to 1.0×1017 ?·cm.Type: GrantFiled: October 15, 2020Date of Patent: July 13, 2021Assignee: CANON KABUSHIKI KAISHAInventors: Noriyoshi Umeda, Tsuneyoshi Tominaga, Shohei Tsuda, Shohei Kototani, Masahiro Kurachi, Kazuhiro Yamauchi, Hideo Kihara
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Patent number: 11022933Abstract: A process cartridge includes a seal member contacting an image bearing member upstream in the rotation direction of the image bearing member from a cleaning member and allowing the developer to move from upstream in the rotation direction from the contact part between the seal member and the image bearing to downstream from the contact part while regulating movement from downstream to upstream from the contact part. The developer has surface protrusions containing an organic silicon polymer, wherein either (i) the work function of the seal member is greater than the work function of the developer when the developer has a negative charging polarity and is smaller than the work function of the developer when the developer has a positive charging polarity, or (ii) the absolute value of the difference between the work function of the seal member and the work function of the developer is within a predetermined range.Type: GrantFiled: May 15, 2020Date of Patent: June 1, 2021Assignee: CANON KABUSHI KIKAISHAInventors: Kazunori Hashimoto, Katsuhiro Kojima, Toshiaki Takeuchi, Yasukazu Ikami, Kosuke Ikada, Yoshihiro Mitsui, Yuichiro Hirata, Go Shindo, Akinobu Saito, Yuhei Terui, Noriyoshi Umeda, Tomonori Matsunaga, Shohei Kototani, Masamichi Sato
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Publication number: 20210116832Abstract: An electrophotographic apparatus comprising an electrophotographic photosensitive member, a charging unit, and a developing unit, wherein the charging unit has a conductive member contactable with the electrophotographic photosensitive member, and a conductive layer of the conductive member has a matrix-domain structure; at least some of the domains are exposed at the outer surface; a volume resistivity R1 of the matrix and a volume resistivity R2 of the domains satisfy specific relationship; Martens hardness G1 of the matrix and Martens hardness G2 of the domains satisfy relationship G1<G2; the surface roughness Ra of the conductive member is not more than 2.00 ?m; the toner has an external additive having a shape factor SF-1 of not more than 115; and A<Dms is satisfied where A is the number-average diameter of the external additive and Dms is a distance between adjacent walls between the domains.Type: ApplicationFiled: October 15, 2020Publication date: April 22, 2021Inventors: Shohei Kototani, Noriyoshi Umeda, Tsuneyoshi Tominaga, Shohei Tsuda, Noboru Miyagawa, Kazuhiro Yamauchi
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Publication number: 20210116831Abstract: An electrophotographic apparatus including an electrophotographic photosensitive member, a charging unit, and a developing unit, wherein the charging unit includes a conductive member disposed to be contactable with the electrophotographic photosensitive member, a conductive layer of the conductive member has a matrix-domain structure, at least some of the domains are exposed at the outer surface of the conductive member, the volume resistivity RI of the matrix is greater than 1.00×1012 ?·cm and not greater than 1.00×1017 ?·cm, the matrix volume resistivity R1 is at least 1.0×105-times the domain volume resistivity R2, and the developing unit includes a toner, the toner includes a binder resin-containing toner particle and an external additive, and the external additive contains fine particles of a hydrotalcite compound.Type: ApplicationFiled: October 15, 2020Publication date: April 22, 2021Inventors: Tsuneyoshi Tominaga, Shohei Tsuda, Shohei Kototani, Noriyoshi Umeda, Masahiro Kurachi, Kazuhiro Yamauchi, Motonari Ito
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Publication number: 20210116828Abstract: 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 on the conductive member outer surface comprises a matrix and a plurality of domains dispersed in the matrix, at least some of the domains are exposed at the conductive member outer surface, the matrix has a volume resistivity of larger than 1.00×1012 ?·cm and is 1.0×105 times or more one of the domains, the developing device comprises the toner comprising a toner particle, fine particles A and B, the fine particle A has a volume resistivity of 1.0×103 to 1.0×1010 ?·cm, and the fine particle B is silica fine particle and having a volume resistivity of 1.0×1011 to 1.0×1017 ?·cm.Type: ApplicationFiled: October 15, 2020Publication date: April 22, 2021Inventors: Noriyoshi Umeda, Tsuneyoshi Tominaga, Shohei Tsuda, Shohei Kototani, Masahiro Kurachi, Kazuhiro Yamauchi, Hideo Kihara
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Patent number: 10976678Abstract: Provided is a toner including a toner particle containing a binder resin, and an external additive, wherein the external additive contains an external additive A and an external additive B, the external additive A is an organosilicon polymer fine particle, the number-average particle diameter of primary particles of the organosilicon polymer fine particle is from 30 to 300 nm, the external additive B is a silica fine particle, the number-average particle diameter of primary particles of the silica fine particle is from 100 to 300 nm, the fixing rate of the external additive A to the toner particle according to a water washing method is less than 30%, and the fixing rate of the external additive B to the toner particle according to the washing method is at least 30%.Type: GrantFiled: December 27, 2019Date of Patent: April 13, 2021Assignee: CANON KABUSHIKI KAISHAInventors: Kentaro Yamawaki, Shohei Kototani, Noriyoshi Umeda, Tomonori Matsunaga, Shohei Tsuda, Satoshi Otsuji
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Publication number: 20210003934Abstract: A toner comprising: a toner particle including a binder resin; and an external additive, wherein the external additive includes an external additive A which is silica fine particles and an external additive B which is a fatty acid metal salt, the external additive A has a specific particle diameter, a coverage ratio of a surface of the toner particle with the external additive A is from 60% to 80%, and where an average theoretical surface area obtained from a number average particle diameter, a particle size distribution and a true density of the toner particle is denoted by C (m2/g), an amount of the external additive B is denoted by D (parts by mass) and a coverage ratio of the surface of the toner particle with the external additive B is denoted by E (%), following formulas are satisfied: 0.05?D/C?2.00 E/(D/C)?50.0.Type: ApplicationFiled: June 25, 2020Publication date: January 7, 2021Inventors: Hidekazu Fumita, Noriyoshi Umeda, Tomonori Matsunaga, Satoshi Otsuji
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Patent number: 10845721Abstract: A toner has a toner particle that has a binder resin and a release agent, wherein when the temperature when G?=1.0×105 Pa in a dynamic viscoelastic measurement on the toner is denoted by Ta, and the glass transition temperature in a differential scanning calorimetric measurement on the toner is denoted by Tg, the Ta and the Tg satisfy the following formulas: 40° C.?Tg?70° C., 60° C.?Ta?90° C., and 0° C.?Ta?Tg?35° C.; and the toner has a storage elastic modulus G? having a minimum value in the range from 110° C. to 150° C. in a dynamic viscoelastic measurement on the toner.Type: GrantFiled: October 14, 2019Date of Patent: November 24, 2020Assignee: CANON KABUSHIKI KAISHAInventors: Masatake Tanaka, Tsuneyoshi Tominaga, Noriyoshi Umeda, Satoshi Otsuji, Shinsuke Mochizuki
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Publication number: 20200363768Abstract: A process cartridge includes a seal member contacting an image bearing member upstream in the rotation direction of the image bearing member from a cleaning member and allowing the developer to move from upstream in the rotation direction from the contact part between the seal member and the image bearing to downstream from the contact part while regulating movement from downstream to upstream from the contact part. The developer has surface protrusions containing an organic silicon polymer, wherein either (i) the work function of the seal member is greater than the work function of the developer when the developer has a negative charging polarity and is smaller than the work function of the developer when the developer has a positive charging polarity, or (ii) the absolute value of the difference between the work function of the seal member and the work function of the developer is within a predetermined range.Type: ApplicationFiled: May 15, 2020Publication date: November 19, 2020Inventors: Kazunori Hashimoto, Katsuhiro Kojima, Toshiaki Takeuchi, Yasukazu Ikami, Kosuke Ikada, Yoshihiro Mitsui, Yuichiro Hirata, Go Shindo, Akinobu Saito, Yuhei Terui, Noriyoshi Umeda, Tomonori Matsunaga, Shohei Kototani, Masamichi Sato
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Publication number: 20200292955Abstract: A toner comprising: a toner particle that contains a release agent-containing toner base particle, and an organosilicon polymer on a toner base particle surface, and an external additive A, the organosilicon polymer has a T3 unit structure; the organosilicon polymer forms protruded portions on the toner base particle surface; the number-average value of the protrusion height H is from 30 nm to 300 nm; the ratio of the number-average primary particle diameter R of the external additive A to the number-average value of the protrusion height H is from 1.00 to 4.00; the number-average primary particle diameter R of the external additive A is from 30 nm to 1,200 nm; and, in an image obtained by observing the toner surface with SEM, the area percentage for the bright region area in the image with reference to the total area of the image is from 30.0% to 75.0%.Type: ApplicationFiled: March 11, 2020Publication date: September 17, 2020Inventors: Tomonori Matsunaga, Hidekazu Fumita, Noriyoshi Umeda, Shohei Tsuda
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Patent number: 10747133Abstract: A image-forming apparatus includes a plurality of process cartridges each having a toner and an image bearing member, and has an intermediate transfer member, wherein the toner comprises a toner particle that contains a toner base particle and a prescribed organosilicon polymer on the surface of the toner base particle, and the organosilicon polymer forms protruded portions on the surface of the toner base particle, for the protrusions having a protrusion height H from 40 nm to 300 nm, the numerical proportion P(D/w) of protruded portions having a ratio of the protrusion diameter D to the protrusion width w in a prescribed range is at least 70 number %, and one of the plurality of process cartridges has a carbon black-containing black toner, and the weight-average particle diameter of this black toner is smaller than that of the toner present in the other process cartridges.Type: GrantFiled: July 12, 2019Date of Patent: August 18, 2020Assignee: CANON KABUSHIKI KAISHAInventors: Yasutaka Yagi, Yuhei Terui, Noriyoshi Umeda, Tomonori Matsunaga, Shohei Kototani, Masamichi Sato
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Publication number: 20200209766Abstract: Provided is a toner including a toner particle containing a binder resin, and an external additive, wherein the external additive contains an external additive A and an external additive B, the external additive A is an organosilicon polymer fine particle, the number-average particle diameter of primary particles of the organosilicon polymer fine particle is from 30 to 300 nm, the external additive B is a silica fine particle, the number-average particle diameter of primary particles of the silica fine particle is from 100 to 300 nm, the fixing rate of the external additive A to the toner particle according to a water washing method is less than 30%, and the fixing rate of the external additive B to the toner particle according to the washing method is at least 30%.Type: ApplicationFiled: December 27, 2019Publication date: July 2, 2020Inventors: Kentaro Yamawaki, Shohei Kototani, Noriyoshi Umeda, Tomonori Matsunaga, Shohei Tsuda, Satoshi Otsuji
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Patent number: 10678155Abstract: A toner comprising a toner particle that contains a toner base particle and an organosilicon polymer on a surface of the toner base particle, wherein the organosilicon polymer forms protruded portions with a prescribed structure on the surface of the toner base particle, and in the toner cross section, when the protrusion width w is the length of the segment where a protruded portion and the toner base particle form a continuous interface, the protrusion diameter D is the maximum length of a protruded portion, and the protrusion height H is the length from the peak of the protruded portion to the line along the circumference of the toner base particle surface, the numerical proportion of these protruded portions having a ratio D/w of the protrusion diameter D to the protrusion width w from 0.33 to 0.80, is a least 70 number %.Type: GrantFiled: July 11, 2019Date of Patent: June 9, 2020Assignee: CANON KABUSHIKI KAISHAInventors: Yuhei Terui, Noriyoshi Umeda, Tomonori Matsunaga, Shohei Kototani, Masamichi Sato
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Patent number: 10635011Abstract: A toner comprising a toner particle having a binder resin, a wax and a colorant, and metal titanate fine particles having a perovskite crystal structure, wherein in cross section observation of the toner using a transmission electron microscope, when a proportion of an area occupied by the wax in a surface layer region from the surface of the toner particle to a depth of 1.0 ?m is denoted by As, the As is from 5.0% to 30.0%, and a number average particle diameter of primary particles of the metal titanate fine particles is from 10 nm to 80 nm.Type: GrantFiled: April 24, 2019Date of Patent: April 28, 2020Assignee: CANON KABUSHIKI KAISHAInventors: Noriyoshi Umeda, Tsuneyoshi Tominaga, Hidekazu Fumita, Taiji Katsura, Shinsuke Mochizuki
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Publication number: 20200124999Abstract: A toner has a toner particle that has a binder resin and a release agent, wherein when the temperature when G?=1.0×105 Pa in a dynamic viscoelastic measurement on the toner is denoted by Ta, and the glass transition temperature in a differential scanning calorimetric measurement on the toner is denoted by Tg, the Ta and the Tg satisfy the following formulas: 40° C.?Tg?70° C., 60° C.?Ta?90° C., and 0° C.?Ta?Tg?35° C.; and the toner has a storage elastic modulus G? having a minimum value in the range from 110° C. to 150° C. in a dynamic viscoelastic measurement on the toner.Type: ApplicationFiled: October 14, 2019Publication date: April 23, 2020Inventors: Masatake Tanaka, Tsuneyoshi Tominaga, Noriyoshi Umeda, Satoshi Otsuji, Shinsuke Mochizuki
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Publication number: 20200026208Abstract: A toner comprising a toner particle that contains a toner base particle and an organosilicon polymer on a surface of the toner base particle, wherein the organosilicon polymer forms protruded portions with a prescribed structure on the surface of the toner base particle, and in the toner cross section, when the protrusion width w is the length of the segment where a protruded portion and the toner base particle form a continuous interface, the protrusion diameter D is the maximum length of a protruded portion, and the protrusion height H is the length from the peak of the protruded portion to the line along the circumference of the toner base particle surface, the numerical proportion of these protruded portions having a ratio D/w of the protrusion diameter D to the protrusion width w from 0.33 to 0.80, is a least 70 number %.Type: ApplicationFiled: July 11, 2019Publication date: January 23, 2020Inventors: Yuhei Terui, Noriyoshi Umeda, Tomonori Matsunaga, Shohei Kototani, Masamichi Sato