Patents by Inventor Bhaskar Gopalanarayanan
Bhaskar Gopalanarayanan 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: 8522438Abstract: A method for making a developer roll by molding a metal shaft with a conductive or semi-conductive soft rubber forming a rubber core and a coating deposited on the soft rubber core wherein the coating has a conductive agent. The outer surface of the soft rubber core is modified to form an —OH rich surface layer before the coating is deposited onto the outer surface of the rubber core to chemically bond therein.Type: GrantFiled: December 18, 2012Date of Patent: September 3, 2013Assignee: Lexmark International, Inc.Inventors: Bhaskar Gopalanarayanan, Kelly Ann Killeen, Johnny Dale Massie, II, Ronald Lloyd Roe, James Joseph Semler
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Patent number: 8500616Abstract: The present disclosure relates to controlling a performance characteristic of an image forming device component having a surface which may include removal of a portion of the surface to expose a plurality of voids and a surface between the voids. The surface between the voids may have a surface roughness Ra in the range of 0.1 to 5.0 microns and the relationship SAV/(SAV+SAC) is equal to 1-50%, where SAV is the surface area of the voids and SAC is the remaining surface area of the component. The performance characteristic may include the control of toner mass conveyed and/or toner filming and/or the amount of residual toner removed from a photoconductive surface.Type: GrantFiled: October 9, 2007Date of Patent: August 6, 2013Assignee: Lexmark International, Inc.Inventors: Johnathan Lee Barnes, Jeannette Quinn Bracken, Sudha Chopra, Jeremy Lavern Daum, Gerald Lee Fish, Bhaskar Gopalanarayanan, Leea Danielle Haarz, Ronald Lloyd Roe, Matthew Joe Russell, James Joseph Semler, Todd Joseph Svoboda
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Patent number: 8448336Abstract: An endless electrophotographic member, such as a developer roller, which indicates an improved resistance to nip banding. The improvement to nip banding may be provided by the use of an organic salt within a roller surface region. The roller may provide, at a nip location, a resistive surface layer having an electrical resistance that avoids the development of nip banding and relatively dark regions on printed media.Type: GrantFiled: July 3, 2008Date of Patent: May 28, 2013Assignee: Lexmark International, Inc.Inventors: Jane Elece Barcelo, Bradley Leonard Beach, Liam Ruan De Paor, Mark Duane Foster, Terence Edward Franey, Bhaskar Gopalanarayanan, Kevin Scott Kennedy, Kelly Ann Killeen, Chao Li, Jean Marie Massie, Ronald Lloyd Roe, Richard Nicholas Schrantz, Jr., Scott Alan Searls, Robert Francis Soto, Donald Wayne Stafford
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Patent number: 8398532Abstract: Developer roll having a conductive or semi-conductive soft rubber core and a coating deposited in the soft rubber core wherein the coating has a conductive agent. The outer surface of the soft rubber core is modified before the coating is deposited onto the outer surface of the soft rubber core. Methods for making the same.Type: GrantFiled: March 7, 2007Date of Patent: March 19, 2013Assignee: Lexmark International, Inc.Inventors: Bhaskar Gopalanarayanan, Kelly Ann Killeen, Johnny Dale Massie, II, Ronald Lloyd Roe, James Joseph Semler
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Patent number: 8038591Abstract: The present disclosure relates to an image forming device component that includes an elastomeric material having a surface and a triboelectric charging material that may be exposed on the elastomeric material surface. The triboelectric material may be exposed by a finishing process that results in removal of a portion of the material leaving voids in the surface. The surface may have a surface roughness in the range of about 0.1 to 5.0 Ra. The component may include a developer roller in an electrophotograhic printer and may provide contact electrification to a given toner during a printing operation.Type: GrantFiled: March 27, 2007Date of Patent: October 18, 2011Assignee: Lexmark International, Inc.Inventors: Jonathan Lee Barnes, Jenny Marie Berens, Bhaskar Gopalanarayanan, Jason Edward Gordon, David Starling MacMillan, Gregory Lawrence Ream, Ronald Lloyd Roe
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Publication number: 20100003610Abstract: An endless electrophotographic member, such as a developer roller, which indicates an improved resistance to nip banding. The improvement to nip banding may be provided by the use of an organic salt within a roller surface region. The roller may provide, at a nip location, a resistive surface layer having an electrical resistance that avoids the development of nip banding and relatively dark regions on printed media.Type: ApplicationFiled: July 3, 2008Publication date: January 7, 2010Inventors: Jane Elece Barcelo, Bradley Leonard Beach, Liam Ruan De Paor, Mark Duane Foster, Terence Edward Franey, Bhaskar Gopalanarayanan, Kevin Scott Kennedy, Kelly Ann Killeen, Chao Li, Jean Marie Massie, Ronald Lloyd Roe, Richard Nicholas Schrantz, JR., Scott Alan Searls, Robert Francis Soto, Donald Wayne Stafford
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Publication number: 20090092420Abstract: The present disclosure relates to controlling a performance characteristic of an image forming device component having a surface which may include removal of a portion of the surface to expose a plurality of voids and a surface between the voids. The surface between the voids may have a surface roughness Ra in the range of 0.1 to 5.0 microns and the relationship SAV/(SAV+SAC) is equal to 1-50%, where SAV is the surface area of the voids and SAC is the remaining surface area of the component. The performance characteristic may include the control of toner mass conveyed and/or toner filming and/or the amount of residual toner removed from a photoconductive surface.Type: ApplicationFiled: October 9, 2007Publication date: April 9, 2009Inventors: Johnathan Lee Barnes, Jeanette Quinn Bracken, Sudha Chopra, Jeremy Lavern Daum, Gerald Lee Fish, Bhaskar Gopalanarayanan, Leea Danielle Haarz, Ronald Lloyd Roe, Matthew Joe Russell, James Joseph Semler, Todd Joseph Svoboda
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Publication number: 20080240810Abstract: The present disclosure relates to an image forming device component that includes an elastomeric material having a surface and a triboelectric charging material that may be exposed on the elastomeric material surface. The triboelectric material may be exposed by a finishing process that results in removal of a portion of the material leaving voids in the surface. The surface may have a surface roughness in the range of about 0.1 to 5.0 Ra. The component may include a developer roller in an electrophotograhic printer and may provide contact electrification to a given toner during a printing operation.Type: ApplicationFiled: March 27, 2007Publication date: October 2, 2008Inventors: Jonathan Lee Barnes, Jenny Marie Berens, Bhaskar Gopalanarayanan, Jason Edward Gordon, David Starling MacMillan, Gregory Lawrence Ream, Ronald Lloyd Roe
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Publication number: 20080219713Abstract: Developer roll having a conductive or semi-conductive soft rubber core and a coating deposited in the soft rubber core wherein the coating has a conductive agent. The outer surface of the soft rubber core is modified before the coating is deposited onto the outer surface of the soft rubber core. Methods for making the same.Type: ApplicationFiled: March 7, 2007Publication date: September 11, 2008Inventors: Bhaskar Gopalanarayanan, Kelly Ann Killeen, Johnny Dale Massie, Ronald Lloyd Roe, James Joseph Semler
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Patent number: 7347808Abstract: Rolls having a polyurethane elastomer formed from a polyurethane mixture, wherein the polyurethane mixture comprises polydiene, tri-functional polyol curative, an additional graft polymer curative having a molecular weight of at least about 800 and comprising diol, polyol, diamine, polyamine or a combination thereof, conductive modifier, antioxidant, and hydrolytic stabilizer. Methods of forming such rolls include casting the polyurethane mixture, followed by curing, then demolding, grinding to desired dimensions and baking such that the outer layer of the cured roll is oxidized.Type: GrantFiled: January 13, 2004Date of Patent: March 25, 2008Assignee: Lexmark International, Inc.Inventors: Bradley L. Beach, Bhaskar Gopalanarayanan, Johnny D. Massie, II
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Publication number: 20070237925Abstract: A radiation cured coating may be applied to a device in an image forming apparatus. The coating may be textured using an embossing method wherein radiation is passed through an embossing device to react a chemical component of the coating. The coating may also be textured by providing multiple coating layers exhibiting differential shrinkage upon exposure to radiation and reacting.Type: ApplicationFiled: April 7, 2006Publication date: October 11, 2007Inventors: Scott Castle, Sudha Chopra, Marc Cousoulis, Gary Denton, Bhaskar Gopalanarayanan, Bart Mansdorf, Vernon Ulrich, Mark Weisman
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Patent number: 7231163Abstract: The present invention relates generally to image forming equipment, e.g. a laser printer of the type which includes a photoconductive (PC) drum and an associated charge roller. The invention is disclosed in exemplary embodiment as a laser printer incorporating a cleaner element with an electrical potential to sufficiently charge contamination particles on the PC drum to electrically repel from a charged surface, such as the charge roller.Type: GrantFiled: February 11, 2005Date of Patent: June 12, 2007Assignee: Lexmark International, Inc.Inventors: Bhaskar Gopalanarayanan, Robert Watson McAlpine, Jamie Piotrowski, Donald Wayne Stafford
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Patent number: 7166358Abstract: The invention is directed to rolls comprising a polyurethane elastomer formed from a polyurethane mixture comprising, inter alia, at least one graft polyacrylate curative, and processes for manufacturing such rolls. The roll is suitable for employment in image forming devices, for example in electrophotographic print applications.Type: GrantFiled: January 13, 2004Date of Patent: January 23, 2007Assignee: Lexmark International, Inc.Inventors: Bhaskar Gopalanarayanan, Kelly A. Killeen, Johnny D. Massie, II, Jing X. Sun
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Publication number: 20060182475Abstract: The present invention relates generally to image forming equipment, e.g. a laser printer of the type which includes a photoconductive (PC) drum and an associated charge roller. The invention is disclosed in exemplary embodiment as a laser printer incorporating a cleaner element with an electrical potential to sufficiently charge contamination particles on the PC drum to electrically repel from a charged surface, such as the charge roller.Type: ApplicationFiled: February 11, 2005Publication date: August 17, 2006Inventors: Bhaskar Gopalanarayanan, Robert McAlpine, Jamie Piotrowski, Donald Stafford
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Patent number: 7034097Abstract: Polyurethane elastomers are formed from first and second graft curatives, each graft curative having a molecular weight of at least about 800, wherein the first and second graft curatives are substantially immiscible with one another, and wherein the polyurethane elastomer exhibits a hardness of less than about 40 Shore A according to ASTM D2240-86 and a compression set of less than about 8% according to ASTM D395-89, method B, at a temperature of about 70° C. for about 22 hours. Rolls are manufactured using such polyurethane elastomers, particularly rolls that are suitable for use in image forming devices, such as electrophotographic print applications.Type: GrantFiled: January 13, 2004Date of Patent: April 25, 2006Assignee: Lexmark International, Inc.Inventors: Bradley L. Beach, Bhaskar Gopalanarayanan, Kelly A. Killeen, Johnny D. Massie, II, Ronald L. Roe
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Patent number: 6970672Abstract: A toner layer regulating system for an electrophotographic image forming apparatus includes a toner carrier; a toner regulating member supported in cantilevered fashion against the toner carrier so as to form a toner nip therebetween comprising a flexible metallic substrate having a coating covering at least an area forming the nip; wherein the coating comprises at least a matrix of a base polymer and a plurality of fine particles having a particle size of 0.1 microns to thirty microns; wherein the coating has a thickness of approximately one hundred fifty microns or less; wherein the coating has a surface roughness in the range of 0.15 to 1.5 microns Ra and in the range of 1 to 15 microns Rz. A carrier stratum may be disposed between the coating and the substrate, and the coating may be single layer or have a plurality of layers.Type: GrantFiled: March 25, 2004Date of Patent: November 29, 2005Assignee: Lexmark International, Inc.Inventors: David Starling MacMillan, Vernon Wayne Ulrich, Jarrett C. Gayne, Scott Richard Castle, Ligia Aura Bejat, Ronald Lloyd Roe, Bhaskar Gopalanarayanan
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Publication number: 20050214033Abstract: A toner layer regulating system for an electrophotographic image forming apparatus includes a toner carrier; a toner regulating member supported in cantilevered fashion against the toner carrier so as to form a toner nip therebetween comprising a flexible metallic substrate having a coating covering at least an area forming the nip; wherein the coating comprises at least a matrix of a base polymer and a plurality of fine particles having a particle size of 0.1 microns to thirty microns; wherein the coating has a thickness of approximately one hundred fifty microns or less; wherein the coating has a surface roughness in the range of 0.15 to 1.5 microns Ra and in the range of 1 to 15 microns Rz. A carrier stratum may be disposed between the coating and the substrate, and the coating may be single layer or have a plurality of layers.Type: ApplicationFiled: March 25, 2004Publication date: September 29, 2005Inventors: David MacMillan, Vernon Ulrich, Jarrett Gayne, Scott Castle, Ligia Bejat, Ronald Roe, Bhaskar Gopalanarayanan
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Patent number: 6935734Abstract: An apparatus for ink-jet printing including an ink-jet print head to jet ink, a coating solid, and a coating holder to support the coating solid, wherein the coating holder transfers a portion of the coating solid onto a medium to form a coating solid layer. The coating holder and coating solid may be combined in a removable cartridge. In addition, the medium may be an intermediate transfer medium, a media support medium, a transfer medium, or media, such as paper. A method for inkjet printing also includes applying a coating solid to a medium to form a layer of the coating solid, in a solid form, having predetermined thickness, and applying ink to the medium. The layer of coating solid may interact with the applied ink to destabilize colorant in the ink.Type: GrantFiled: June 3, 2003Date of Patent: August 30, 2005Assignee: Lexmark International, Inc.Inventors: Benjamin A. Askren, Ronald W. Baker, Ligia Aura Bejat, Charles J. Cheek, Gerald L. Fish, Hrishikesh Pramod Gogate, Bhaskar Gopalanarayanan, Jason Gordon, Philip J. Heink, John W. Kietzman, Michael C. Leemhuis, Claudia A. Marin, Sean D. Smith, Donald W. Stafford
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Publication number: 20050154149Abstract: Rolls having a polyurethane elastomer formed from a polyurethane mixture, wherein the polyurethane mixture comprises polydiene, tri-functional polyol curative, an additional graft polymer curative having a molecular weight of at least about 800 and comprising diol, polyol, diamine, polyamine or a combination thereof, conductive modifier, antioxidant, and hydrolytic stabilizer. Methods of forming such rolls include casting the polyurethane mixture, followed by curing, then demolding, grinding to desired dimensions and baking such that the outer layer of the cured roll is oxidized.Type: ApplicationFiled: January 13, 2004Publication date: July 14, 2005Inventors: Bradley Beach, Bhaskar Gopalanarayanan, Johnny Massie
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Publication number: 20050154102Abstract: The invention is directed to rolls comprising a polyurethane elastomer formed from a polyurethane mixture comprising, inter alia, at least one graft polyacrylate curative, and processes for manufacturing such rolls. The roll is suitable for employment in image forming devices, for example in electrophotographic print applications.Type: ApplicationFiled: January 13, 2004Publication date: July 14, 2005Inventors: Bhaskar Gopalanarayanan, Kelly Killeen, Johnny Massie, Jing Sun