Patents by Inventor Kasturi Rangan Srinivasan

Kasturi Rangan Srinivasan 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).

  • Publication number: 20200319570
    Abstract: A method for producing a chemically prepared magenta toner composition according to one example embodiment includes combining and agglomerating a first polymer emulsion with a magenta colorant dispersion containing a single azo magenta pigment and a release agent dispersion to form toner cores. A borax coupling agent is added to the toner cores. A second polymer emulsion is combined and agglomerated with the toner cores having the borax coupling agent to form toner shells around the toner cores. The aggregated toner cores and toner shells are fused to form magenta toner particles. The single azo magenta pigment in the magenta pigment dispersion does not aggregate into clusters on the outer surface of the surface core.
    Type: Application
    Filed: April 8, 2019
    Publication date: October 8, 2020
    Inventors: KASTURI RANGAN SRINIVASAN, ASHLEY SCHAFER GRANT, MICHAEL JAMES BENSING
  • Patent number: 10795275
    Abstract: A method for producing a chemically prepared magenta toner composition according to one example embodiment includes combining and agglomerating a first polymer emulsion with a magenta colorant dispersion containing a single azo magenta pigment and a release agent dispersion to form toner cores. A borax coupling agent is added to the toner cores. A second polymer emulsion is combined and agglomerated with the toner cores having the borax coupling agent to form toner shells around the toner cores. The aggregated toner cores and toner shells are fused to form magenta toner particles. The single azo magenta pigment in the magenta pigment dispersion does not aggregate into clusters on the outer surface of the surface core.
    Type: Grant
    Filed: April 8, 2019
    Date of Patent: October 6, 2020
    Assignee: LEXMARK INTERNATIONAL, INC.
    Inventors: Kasturi Rangan Srinivasan, Ashley Schafer Grant, Michael James Bensing
  • Patent number: 10613450
    Abstract: The present disclosure relates generally to a method to make a chemically prepared toner that employs a crash cooling process. In particular, the crash cooling process involves the addition of a toner slurry having a temperature between 70° C. and 90° C. to an equivalent amount of cold water having a temperature between 5° C. and 20° C. Polyester and styrene acrylic toners as well as polyester core shell toners having a borax coupling agent between the toner core and toner shell made from this cooling process results in an improvement to the amount of toner waste, thereby achieving a higher toner usage efficiency for an electrophotographic printing system.
    Type: Grant
    Filed: April 3, 2019
    Date of Patent: April 7, 2020
    Assignee: LEXMARK INTERNATIONAL, INC.
    Inventors: Kasturi Rangan Srinivasan, Rahel Bekru Bogale, Trent Duane Peter, Brian David Munson
  • Patent number: 10606181
    Abstract: The toner composition of the present invention and method to make the same includes toner particles mixed with a specific set of extra particulate additives including large colloidal silica sized 90 nm to 120 nm and having a conductivity of less than 20 ?s/cm in combination with medium size silica particles sized 30 nm to 60 nm. Optionally, additional extra particular additives such as silica sized 2 nm to 20 nm, alumina, titania or mixtures thereof can be used. The finished toner having these specific additives exhibited superior printing performance.
    Type: Grant
    Filed: December 27, 2013
    Date of Patent: March 31, 2020
    Assignee: Lexmark International, Inc.
    Inventors: Kasturi Rangan Srinivasan, Rick Owen Jones, Courtney Harrison Soale, Devon Jean Vaccaro Strain, Ligia Aura Bejat
  • Patent number: 10606182
    Abstract: The present disclosure relates generally to a method to make a chemically prepared toner that employs a crash cooling process. In the crash cooling process, hot toner slurry is added to an external reactor containing a coolant comprised of previously cooled toner slurry in combination with cooled de-ionized water. The previously cooled toner slurry found in the coolant has the same toner composition as the incoming hot toner slurry. Also, the amount of the coolant in the external reactor is equivalent to the amount of incoming hot toner slurry. Polyester toners and polyester core shell toners having a borax coupling agent between the toner core and toner shell made from this crash cooling process results in an improvement to the toner performance especially a decrease in the overall toner usage.
    Type: Grant
    Filed: April 16, 2019
    Date of Patent: March 31, 2020
    Assignee: LEXMARK INTERNATIONAL, INC.
    Inventors: Kasturi Rangan Srinivasan, Anna Sara McLeland, Rahel Bekru Bogale
  • Patent number: 10591833
    Abstract: The present disclosure relates generally to a method to make a chemically prepared toner that employs a crash cooling process. In the crash cooling process, an amount of hot toner slurry is added to an external reactor holding an amount of chilled cooling water, wherein the temperature of the chilled cooling water in the external reactor is from about 8° C. to about 25° C. The amount of the chilled cooling water in the external reactor is about 10% to about 40% lower compared to the amount of the added hot toner slurry. Toner prepared using this crash cooling method is cooled at a rate of less than 0.8° C./min. Polyester toners and polyester core shell toners having a borax coupling agent between the toner core and toner shell made from this crash cooling processes using less water results in an improvement to the toner's print density and usage efficiency.
    Type: Grant
    Filed: April 16, 2019
    Date of Patent: March 17, 2020
    Assignee: LEXMARK INTERNATIONAL, INC.
    Inventors: Kasturi Rangan Srinivasan, Anna Sara McLeland, Rahel Bekru Bogale, Trent Duane Peter
  • Patent number: 10591831
    Abstract: The present disclosure relates generally to a method to make a chemically prepared toner that employs a crash cooling process. In the crash cooling process, hot toner slurry is added to an external reactor containing a coolant comprised of previously cooled toner slurry in combination with cooled de-ionized water. The previously cooled toner slurry found in the coolant has the same toner composition as the incoming hot toner slurry. Also, the amount of the coolant in the external reactor is equivalent to the amount of incoming hot toner slurry. Polyester toners and polyester core shell toners having a borax coupling agent between the toner core and toner shell made from this crash cooling process results in an improvement to the toner performance especially a decrease in the overall toner usage.
    Type: Grant
    Filed: April 16, 2019
    Date of Patent: March 17, 2020
    Assignee: LEXMARK INTERNATIONAL, INC.
    Inventors: Kasturi Rangan Srinivasan, Anna Sara McLeland, Rahel Bekru Bogale
  • Patent number: 10591832
    Abstract: The present disclosure relates generally to a method to make a chemically prepared toner that employs a crash cooling process. In the crash cooling process, hot toner slurry is added to an external reactor containing a coolant comprised of previously cooled toner slurry in combination with cooled de-ionized water. The previously cooled toner slurry found in the coolant has the same toner composition as the incoming hot toner slurry. Also, the amount of the coolant in the external reactor is equivalent to the amount of incoming hot toner slurry. Polyester toners and polyester core shell toners having a borax coupling agent between the toner core and toner shell made from this crash cooling process results in an improvement to the toner performance especially a decrease in the overall toner usage.
    Type: Grant
    Filed: April 16, 2019
    Date of Patent: March 17, 2020
    Assignee: LEXMARK INTERNATIONAL, INC.
    Inventors: Kasturi Rangan Srinivasan, Anna Sara McLeland, Rahel Bekru Bogale
  • Patent number: 10591835
    Abstract: The present disclosure relates generally to a method to make a chemically prepared toner that employs a crash cooling process. In the crash cooling process, an amount of hot toner slurry is added to an external reactor holding an amount of chilled cooling water, wherein the temperature of the chilled cooling water in the external reactor is from about 8° C. to about 25° C. The amount of the chilled cooling water in the external reactor is about 10% to about 40% lower compared to the amount of the added hot toner slurry. Toner prepared using this crash cooling method is cooled at a rate of less than 0.8° C./min. Polyester toners and polyester core shell toners having a borax coupling agent between the toner core and toner shell made from this crash cooling processes using less water results in an improvement to the toner's print density and usage efficiency.
    Type: Grant
    Filed: April 16, 2019
    Date of Patent: March 17, 2020
    Assignee: LEXMARK INTERNATIONAL, INC.
    Inventors: Kasturi Rangan Srinivasan, Anna Sara McLeland, Rahel Bekru Bogale, Trent Duane Peter
  • Patent number: 10591834
    Abstract: The present disclosure relates generally to a method to make a chemically prepared toner that employs a crash cooling process. In the crash cooling process, an amount of hot toner slurry is added to an external reactor holding an amount of chilled cooling water, wherein the temperature of the chilled cooling water in the external reactor is from about 8° C. to about 25° C. The amount of the chilled cooling water in the external reactor is about 10% to about 40% lower compared to the amount of the added hot toner slurry. Toner prepared using this crash cooling method is cooled at a rate of less than 0.8° C./min. Polyester toners and polyester core shell toners having a borax coupling agent between the toner core and toner shell made from this crash cooling processes using less water results in an improvement to the toner's print density and usage efficiency.
    Type: Grant
    Filed: April 16, 2019
    Date of Patent: March 17, 2020
    Assignee: LEXMARK INTERNATIONAL, INC.
    Inventors: Kasturi Rangan Srinivasan, Anna Sara McLeland, Rahel Bekru Bogale, Trent Duane Peter
  • Patent number: 10474046
    Abstract: The present disclosure relates generally to a method to make a chemically prepared toner that employs a crash cooling process. In particular, the crash cooling process involves the addition of a toner slurry having a temperature between 70° C. and 90° C. to an equivalent amount of cold water having a temperature between 5° C. and 20° C. Polyester and styrene acrylic toners as well as polyester core shell toners having a borax coupling agent between the toner core and toner shell made from this cooling process results in an improvement to the amount of toner waste, thereby achieving a higher toner usage efficiency for an electrophotographic printing system.
    Type: Grant
    Filed: September 21, 2018
    Date of Patent: November 12, 2019
    Assignee: LEXMARK INTERNATIONAL, INC.
    Inventors: Kasturi Rangan Srinivasan, Rahel Bekru Bogale, Trent Duane Peter, Brian David Munson
  • Publication number: 20190243264
    Abstract: The present disclosure relates generally to a method to make a chemically prepared toner that employs a crash cooling process. In the crash cooling process, hot toner slurry is added to an external reactor containing a coolant comprised of previously cooled toner slurry in combination with cooled de-ionized water. The previously cooled toner slurry found in the coolant has the same toner composition as the incoming hot toner slurry. Also, the amount of the coolant in the external reactor is equivalent to the amount of incoming hot toner slurry. Polyester toners and polyester core shell toners having a borax coupling agent between the toner core and toner shell made from this crash cooling process results in an improvement to the toner performance especially a decrease in the overall toner usage.
    Type: Application
    Filed: April 16, 2019
    Publication date: August 8, 2019
    Inventors: KASTURI RANGAN SRINIVASAN, ANNA SARA MCLELAND, RAHEL BEKRU BOGALE
  • Publication number: 20190243263
    Abstract: The present disclosure relates generally to a method to make a chemically prepared toner that employs a crash cooling process. In the crash cooling process, hot toner slurry is added to an external reactor containing a coolant comprised of previously cooled toner slurry in combination with cooled de-ionized water. The previously cooled toner slurry found in the coolant has the same toner composition as the incoming hot toner slurry. Also, the amount of the coolant in the external reactor is equivalent to the amount of incoming hot toner slurry. Polyester toners and polyester core shell toners having a borax coupling agent between the toner core and toner shell made from this crash cooling process results in an improvement to the toner performance especially a decrease in the overall toner usage.
    Type: Application
    Filed: April 16, 2019
    Publication date: August 8, 2019
    Inventors: KASTURI RANGAN SRINIVASAN, ANNA SARA MCLELAND, RAHEL BEKRU BOGALE
  • Publication number: 20190243262
    Abstract: The present disclosure relates generally to a method to make a chemically prepared toner that employs a crash cooling process. In the crash cooling process, hot toner slurry is added to an external reactor containing a coolant comprised of previously cooled toner slurry in combination with cooled de-ionized water. The previously cooled toner slurry found in the coolant has the same toner composition as the incoming hot toner slurry. Also, the amount of the coolant in the external reactor is equivalent to the amount of incoming hot toner slurry. Polyester toners and polyester core shell toners having a borax coupling agent between the toner core and toner shell made from this crash cooling process results in an improvement to the toner performance especially a decrease in the overall toner usage.
    Type: Application
    Filed: April 16, 2019
    Publication date: August 8, 2019
    Inventors: KASTURI RANGAN SRINIVASAN, ANNA SARA MCLELAND, RAHEL BEKRU BOGALE
  • Publication number: 20190243267
    Abstract: The present disclosure relates generally to a method to make a chemically prepared toner that employs a crash cooling process. In the crash cooling process, an amount of hot toner slurry is added to an external reactor holding an amount of chilled cooling water, wherein the temperature of the chilled cooling water in the external reactor is from about 8° C. to about 25° C. The amount of the chilled cooling water in the external reactor is about 10% to about 40% lower compared to the amount of the added hot toner slurry. Toner prepared using this crash cooling method is cooled at a rate of less than 0.8° C./min. Polyester toners and polyester core shell toners having a borax coupling agent between the toner core and toner shell made from this crash cooling processes using less water results in an improvement to the toner's print density and usage efficiency.
    Type: Application
    Filed: April 16, 2019
    Publication date: August 8, 2019
    Inventors: KASTURI RANGAN SRINIVASAN, ANNA SARA MCLELAND, RAHEL BEKRU BOGALE, TRENT DUANE PETER
  • Publication number: 20190243265
    Abstract: The present disclosure relates generally to a method to make a chemically prepared toner that employs a crash cooling process. In the crash cooling process, an amount of hot toner slurry is added to an external reactor holding an amount of chilled cooling water, wherein the temperature of the chilled cooling water in the external reactor is from about 8° C. to about 25° C. The amount of the chilled cooling water in the external reactor is about 10% to about 40% lower compared to the amount of the added hot toner slurry. Toner prepared using this crash cooling method is cooled at a rate of less than 0.8° C./min. Polyester toners and polyester core shell toners having a borax coupling agent between the toner core and toner shell made from this crash cooling processes using less water results in an improvement to the toner's print density and usage efficiency.
    Type: Application
    Filed: April 16, 2019
    Publication date: August 8, 2019
    Inventors: KASTURI RANGAN SRINIVASAN, ANNA SARA MCLELAND, RAHEL BEKRU BOGALE, TRENT DUANE PETER
  • Publication number: 20190243266
    Abstract: The present disclosure relates generally to a method to make a chemically prepared toner that employs a crash cooling process. In the crash cooling process, an amount of hot toner slurry is added to an external reactor holding an amount of chilled cooling water, wherein the temperature of the chilled cooling water in the external reactor is from about 8° C. to about 25° C. The amount of the chilled cooling water in the external reactor is about 10% to about 40% lower compared to the amount of the added hot toner slurry. Toner prepared using this crash cooling method is cooled at a rate of less than 0.8° C./min. Polyester toners and polyester core shell toners having a borax coupling agent between the toner core and toner shell made from this crash cooling processes using less water results in an improvement to the toner's print density and usage efficiency.
    Type: Application
    Filed: April 16, 2019
    Publication date: August 8, 2019
    Inventors: Kasturi Rangan Srinivasan, Anna Sara McLeland, Rahel Berku Bogale, Trent Duane Peter
  • Publication number: 20190227451
    Abstract: The present disclosure relates generally to a method to make a chemically prepared toner that employs a crash cooling process. In particular, the crash cooling process involves the addition of a toner slurry having a temperature between 70° C. and 90° C. to an equivalent amount of cold water having a temperature between 5° C. and 20° C. Polyester and styrene acrylic toners as well as polyester core shell toners having a borax coupling agent between the toner core and toner shell made from this cooling process results in an improvement to the amount of toner waste, thereby achieving a higher toner usage efficiency for an electrophotographic printing system.
    Type: Application
    Filed: April 3, 2019
    Publication date: July 25, 2019
    Inventors: KASTURI RANGAN SRINIVASAN, RAHEL BEKRU BOGALE, TRENT DUANE PETER, BRIAN DAVID MUNSON
  • Publication number: 20190025724
    Abstract: The present disclosure relates generally to a method to make a chemically prepared toner that employs a crash cooling process. In particular, the crash cooling process involves the addition of a toner slurry having a temperature between 70° C. and 90° C. to an equivalent amount of cold water having a temperature between 5° C. and 20° C. Polyester and styrene acrylic toners as well as polyester core shell toners having a borax coupling agent between the toner core and toner shell made from this cooling process results in an improvement to the amount of toner waste, thereby achieving a higher toner usage efficiency for an electrophotographic printing system.
    Type: Application
    Filed: September 21, 2018
    Publication date: January 24, 2019
    Inventors: KASTURI RANGAN SRINIVASAN, RAHEL BEKRU BOGALE, TRENT DUANE PETER, BRIAN DAVID MUNSON
  • Patent number: 10108100
    Abstract: The present disclosure relates generally to a method to make a chemically prepared toner that employs a crash cooling process. In particular, the crash cooling process involves the addition of a toner slurry having a temperature between 70° C. and 90° C. to an equivalent amount of cold water having a temperature between 5° C. and 20° C. Polyester and styrene acrylic toners as well as polyester core shell toners having a borax coupling agent between the toner core and toner shell made from this cooling process results in an improvement to the amount of toner waste, thereby achieving a higher toner usage efficiency for an electrophotographic printing system.
    Type: Grant
    Filed: June 21, 2017
    Date of Patent: October 23, 2018
    Assignee: LEXMARK INTERNATIONAL, INC.
    Inventors: Kasturi Rangan Srinivasan, Rahel Bekru Bogale, Trent Duane Peter, Brian David Munson