Patents by Inventor Daisuke Misawa
Daisuke Misawa 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: 10859934Abstract: A yellow toner is provided. The yellow toner comprises toner particles each comprising a binder resin and a colorant, and 1.0% to 15.0% by number of the toner particles have a CH rate of 25.0% or more in absolute value. Here, the CH rate is calculated from the following formula (1): CH rate (%)=[(In?Iave)/Iave]×100??Formula (1) where In represents an integrated intensity within a wavenumber region of from 2,750 to 3,250 cm?1 when an intensity at a wavenumber ? within a wavenumber region of from 950 to 3,250 cm?1 is normalized to 1 in a Raman spectrum of each toner particle; and Iave represents an average of the In.Type: GrantFiled: December 27, 2019Date of Patent: December 8, 2020Assignee: Ricoh Company, Ltd.Inventors: Hiyori Fujino, Shoki Matsuda, Fumihiko Chimoto, Keisuke Tada, Daisuke Misawa
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Publication number: 20200209772Abstract: A yellow toner is provided. The yellow toner comprises toner particles each comprising a binder resin and a colorant, and 1.0% to 15.0% by number of the toner particles have a CH rate of 25.0% or more in absolute value. Here, the CH rate is calculated from the following formula (1): CH rate (%)=[(In?Iave)/Iave]×100??Formula (1) where In represents an integrated intensity within a wavenumber region of from 2,750 to 3,250 cm?1 when an intensity at a wavenumber ? within a wavenumber region of from 950 to 3,250 cm?1 is normalized to 1 in a Raman spectrum of each toner particle; and Iave represents an average of the In.Type: ApplicationFiled: December 27, 2019Publication date: July 2, 2020Inventors: Hiyori FUJINO, Shoki MATSUDA, Fumihiko CHIMOTO, Keisuke TADA, Daisuke MISAWA
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Patent number: 9201365Abstract: An image forming apparatus, including: photoconductor; charging unit; exposing unit; developing unit containing toner; transfer unit; and fixing unit, wherein the toner includes external additive and base particles containing binder resin, colorant, and release agent, the toner has melt viscosity at 100° C. of 500 Pa·s to 8,000 Pa·s and the release agent has melt viscosity at 100° C. of 20 mPa·s to 30 mPa·s, the fixing unit includes fixing member that has roller or belt shape and contacts toner image transferred onto recording medium, and the fixing member includes release layer on surface thereof that is to be brought into contact with the toner image transferred onto the recording medium, and wherein the release layer satisfies the following expressions: 45??c1?60, and 10??c1??c2, where ?c1 denotes receding contact angle [°] of the release agent to the release layer and ?c2 denotes receding contact angle [°] of the release agent to the toner.Type: GrantFiled: March 13, 2015Date of Patent: December 1, 2015Assignee: Ricoh Company, Ltd.Inventors: Shingo Sakashita, Satoshi Kojima, Daisuke Misawa, Hiroshi Endoh, Tomoki Murayama, Rintaro Takahashi, Chihiro Kikuchi
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Patent number: 9176402Abstract: A method for manufacturing a toner, including at least: dissolving or dispersing a toner material including at least any one of a binder resin and a precursor of a binder resin in an organic solvent which is dispersed in a dispersant-including aqueous medium; forming particles by removing the organic solvent; washing the particles; forming voids in the particles by heating to a temperature T while or after dispersing the particles in an aqueous medium; forming toner base particles by adding a charge controlling agent; and adding an external additive to the toner base particles to obtain toner particles, wherein the T is between a glass transition temperature Tg of the toner particles and Tg+25° C., and the toner has a cross-sectional void fraction Sp/St of 0.1% to 15.0%, where St is a cross-sectional area of the toner particles, and Sp is a cross-sectional area of the voids.Type: GrantFiled: September 12, 2012Date of Patent: November 3, 2015Assignee: Ricoh Company, Ltd.Inventors: Keisuke Tada, Kenichi Uehara, Daisuke Misawa, Ayumi Oikawa, Hiroshi Endoh
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Publication number: 20150261144Abstract: An image forming apparatus, including: photoconductor; charging unit; exposing unit; developing unit containing toner; transfer unit; and fixing unit, wherein the toner includes external additive and base particles containing binder resin, colorant, and release agent, the toner has melt viscosity at 100° C. of 500 Pa·s to 8,000 Pa·s and the release agent has melt viscosity at 100° C. of 20 mPa·s to 30 mPa·s, the fixing unit includes fixing member that has roller or belt shape and contacts toner image transferred onto recording medium, and the fixing member includes release layer on surface thereof that is to be brought into contact with the toner image transferred onto the recording medium, and wherein the release layer satisfies the following expressions: 45??c1?10, and 10??c1??c2, where ?c1 denotes receding contact angle [°] of the release agent to the release layer and ?c2 denotes receding contact angle [°] of the release agent to the toner.Type: ApplicationFiled: March 13, 2015Publication date: September 17, 2015Inventors: Shingo SAKASHITA, Satoshi KOJIMA, Daisuke MISAWA, Hiroshi ENDOH, Tomoki MURAYAMA, Rintaro TAKAHASHI, Chihiro KIKUCHI
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Publication number: 20140342282Abstract: A method for manufacturing a toner, including at least: dissolving or dispersing a toner material including at least any one of a binder resin and a precursor of a binder resin in an organic solvent which is dispersed in a dispersant-including aqueous medium; forming particles by removing the organic solvent; washing the particles; forming voids in the particles by heating to a temperature T while or after dispersing the particles in an aqueous medium; forming toner base particles by adding a charge controlling agent; and adding an external additive to the toner base particles to obtain toner particles, wherein the T is between a glass transition temperature Tg of the toner particles and Tg+25° C., and the toner has a cross-sectional void fraction Sp/St of 0.1% to 15.0%, where St is a cross-sectional area of the toner particles, and Sp is a cross-sectional area of the voids.Type: ApplicationFiled: September 12, 2012Publication date: November 20, 2014Inventors: Keisuke Tada, Kenichi Uehara, Daisuke Misawa, Ayumi Oikawa, Hiroshi Endoh
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Patent number: 8557497Abstract: A method of manufacturing toner including preparing a first liquid by dissolving or dispersing toner components including one or both of a binder resin and a precursor thereof in an organic solvent; preparing a second liquid by dispersing the first liquid in a first aqueous medium including a dispersant; producing primary particles by removing the organic solvent from the second liquid; washing the primary particles; preparing a third liquid by dispersing the washed primary particles in a second aqueous medium and heating the second aqueous medium while or after dispersing the washed primary particles therein; and producing toner particles by adding a charge controlling agent to the third liquid. This method satisfies the following inequation: 0.60?Sb/Sa?1.00 wherein Sa represents a BET specific surface area of the primary particles included in the third liquid and Sb represents that of the toner particles stored for 2 weeks at 40° C., 70% RH.Type: GrantFiled: December 6, 2010Date of Patent: October 15, 2013Assignee: Ricoh Company, LimitedInventors: Junichi Watanabe, Kenichi Uehara, Junya Koeda, Daisuke Misawa, Keisuke Tada, Miyuki Hirata
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Publication number: 20110136052Abstract: A method of manufacturing toner including preparing a first liquid by dissolving or dispersing toner components including one or both of a binder resin and a precursor thereof in an organic solvent; preparing a second liquid by dispersing the first liquid in a first aqueous medium including a dispersant; producing primary particles by removing the organic solvent from the second liquid; washing the primary particles; preparing a third liquid by dispersing the washed primary particles in a second aqueous medium and heating the second aqueous medium while or after dispersing the washed primary particles therein; and producing toner particles by adding a charge controlling agent to the third liquid. This method satisfies the following inequation: 0.60?Sb/Sa?1.00 wherein Sa represents a BET specific surface area of the primary particles included in the third liquid and Sb represents that of the toner particles stored for 2 weeks at 40° C., 70% RH.Type: ApplicationFiled: December 6, 2010Publication date: June 9, 2011Inventors: Junichi WATANABE, Kenichi Uehara, Junya Koeda, Daisuke Misawa, Keisuke Tada, Miyuki Hirata
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Publication number: 20080311504Abstract: A method of manufacturing toner including adding an oil phase comprising an organic solvent in which a binder resin, a coloring agent and a releasing agent are dissolved or dispersed and an aqueous phase to an emulsification device equipped with a stirrer, continuously dispersing or emulsifying the oil phase and the aqueous phase in the emulsification device equipped with a stirrer to form a liquid dispersion or emulsion comprising oil phase particles, transporting the liquid dispersion or emulsion to a tank, removing the organic solvent from the liquid dispersion or emulsion followed by drying to form mother toner particles, wherein the releasing agent has been preliminarily prepared to have a dispersion diameter of from 0.15 to 0.Type: ApplicationFiled: May 21, 2008Publication date: December 18, 2008Inventors: Mizuki HATTORI, Shinzo Higuchi, Takahiro Kadota, Daisuke Misawa, Hiroshi Takahashi, Toshihiko Usami, Masashi Miyakawa