Patents by Inventor Dilip K. Chatterjee

Dilip K. Chatterjee 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).

  • Patent number: 5805968
    Abstract: A fuser for fixing particulate imaging material to a receiver sheet, includes two rollers which engage each other at a fixing nip, wherein pressure is used in fixing the particulate imaging material to the receiver sheet; and at least one of the fusing rollers having a surface formed from zirconia ceramic or its composites which has a hardness greater than 12 GPa and toughness greater than 6 MPa.sqroot.mm.
    Type: Grant
    Filed: March 21, 1997
    Date of Patent: September 8, 1998
    Assignee: Eastman Kodak Company
    Inventors: Dilip K. Chatterjee, Jiann-Hsing Chen, Tonya D. Binga
  • Patent number: 5804342
    Abstract: A method of making a printing member for providing an erasable bar-code including providing a polymeric substrate having an insert cavity; forming an insert member having a writing surface composed of a non-porous zirconia ceramic ZrO.sub.2 that is alloyed with a secondary oxide selected from the group consisting of MgO, CaO, Y.sub.2 O.sub.3, Sc.sub.2 O.sub.3, a rare earth oxide, and combinations thereof, the non-porous zirconia alloy ceramic having a density of from about 5.6 to about 6.2 g/cm.sup.3 ; and providing an erasable bar-code image on the printing member by imagewise exposing the printing surface to electromagnetic radiation that transforms the printing surface from a stoichiometric to a substoichiometric state, thereby creating a printing surface having both image areas and non-image areas.
    Type: Grant
    Filed: July 29, 1997
    Date of Patent: September 8, 1998
    Assignee: Eastman Kodak Company
    Inventors: Gustavo R. Paz-Pujalt, Dilip K. Chatterjee, Syamal K. Ghosh
  • Patent number: 5804131
    Abstract: The present invention is a method of preparing a ceramic article which includes compacting a particulate alloy of a primary oxide and a secondary oxide to form a blank. The primary oxide is zirconium oxide and the secondary oxide is selected from MgO, CaO, Y.sub.2 O.sub.3, Sc.sub.2 O.sub.3,CeO.sub.2 and rare earth oxides and combinations thereof. The blank is sintered in contact with a smectite containing sol.
    Type: Grant
    Filed: October 7, 1997
    Date of Patent: September 8, 1998
    Assignee: Eastman Kodak Company
    Inventors: Debasis Majumdar, Dilip K. Chatterjee, Syamal K. Ghosh
  • Patent number: 5804130
    Abstract: A method for forming an embedded multiwound microcoil in a ceramic substrate including the steps of forming a sacrificial mutiwound microcoil to be used in the ceramic substrate by wrapping a first sacrificial coil winding about the midsection of a sintered ceramic bar thereby forming a one winding sacrificial coil structure; dipping the one winding sacrificial coil structure in a sol-gel precursor and then forming an encapsulated one winding sacrificial coil structure from such sol-gel precursor; wrapping a second sacrificial coil winding about the midsection of the encapsulated one winding sacrificial coil structure thereby forming a two winding sacrificial coil structure.
    Type: Grant
    Filed: July 18, 1997
    Date of Patent: September 8, 1998
    Assignee: Eastman Kodak Company
    Inventors: Edward P. Furlani, Syamal K. Ghosh, Dilip K. Chatterjee
  • Patent number: 5798308
    Abstract: The present invention is a sintered ceramic article having an elemental composition including Zr, O, and at least one element selected from the group consisting of Mg, Ca, Y, Sc, Ce and rare earth elements. The ceramic article includes a core and a casing. The casing is exterior to and continuous with the core. The core is a mass of sintered particles having an essentially tetragonal zirconia crystalline structure and the casing is a mass of sintered particles having a mixture of monoclinic zirconia crystalline structure and zircon crystalline structure.
    Type: Grant
    Filed: October 7, 1997
    Date of Patent: August 25, 1998
    Assignee: Eastman Kodak Company
    Inventors: Dilip K. Chatterjee, Debasis Majumdar, Thomas N. Blanton
  • Patent number: 5795422
    Abstract: A method of fabricating a molded ceramic device having an embedded spiral coil, is disclosed which includes: forming grooves that provide portions of a spiral coil in surfaces of first and second ceramic plates; aligning the grooves in the first and second ceramic plates and sintering the first and second ceramic plates to form a unitary structure; and filling the aligned grooves with sacrificial material. The method further includes removing the sacrificial material from the unitary structure; and filling the grooves with a conductive material to complete a conductive spiral coil.
    Type: Grant
    Filed: January 2, 1997
    Date of Patent: August 18, 1998
    Assignee: Eastman Kodak Company
    Inventors: Dilip K. Chatterjee, Edward P. Furlani, Syamal K. Ghosh
  • Patent number: 5795362
    Abstract: An alumina ceramic article and a method for preparing the article. The method comprises the steps of:(1) Compacting a mixture of a first concentration of particulate aluminum oxide sufficient to prevent retention of the zirconium oxide alloy particles in the surface in a predominantly tetragonal crystal structure and a second concentration of particulate zirconium oxide alloy. The zirconium oxide alloy is zirconium oxide and a secondary oxide selected from the group consisting of MgO, CaO, Y.sub.2 O.sub.3, Sc.sub.2 O.sub.3, CeO.sub.2, and rare earth oxides having a concentration of secondary oxide generally of about 0.5 to about 5 mole percent Y.sub.2 O.sub.3, from about 0.1 to about 1 mole percent MgO, from about 0.5 to about 15 mole percent CeO.sub.2, from about 0.5 to about 7.0 mole percent Sc.sub.2 O.sub.3, or from about 0.5 to about 5 mole percent CaO, relative to the total of the zirconium oxide alloy. The compacting results in the formation of a blank.
    Type: Grant
    Filed: June 25, 1996
    Date of Patent: August 18, 1998
    Assignee: Eastman Kodak Company
    Inventors: Dilip K. Chatterjee, Syamal K. Ghosh, Thomas N. Blanton
  • Patent number: 5786102
    Abstract: An amorphous upconversion phosphor comprising barium fluoride a combination of rare-earth fluorides including yttrium and lanthanum and dopants, and a waveguide thereof on a substrate selected to have a refractive index lower than a thin film of the phosphor material or any other substrate with an appropriate buffer layer of lower refractive index that the film wherein infrared radiation and visible light are converted to ultraviolet and visible light. The amorphous upconversion phosphor is deposited at temperatures low enough to permit integration into semiconductor materials.
    Type: Grant
    Filed: January 16, 1996
    Date of Patent: July 28, 1998
    Assignee: Eastman Kodak Company
    Inventors: Gustavo R. Paz-Pujalt, James M. Chwalek, Anna L. Hrycin, Dilip K. Chatterjee, Liang-Sun Hung
  • Patent number: 5783879
    Abstract: A micromotor in a ceramic substrate, including a unitary ceramic body providing a micromotor substrate which has been formed with a first internal cavity and a plurality of second internal cavities and a recess, a ferromagnetic stator formed in the first internal cavity, and embedded conductive coil structures formed in the second internal cavities and disposed in operative relationship to the ferromagnetic stator, and a rotor mechanism mounted in the recess and in operative relationship to the ferromagnetic stator and having a rotor member formed of a hard magnetic material which is free to rotate so that when voltages are applied to the coil structures, a field is created through the ferromagnetic stator which provides a torque to the rotor member causing it to rotate.
    Type: Grant
    Filed: June 3, 1997
    Date of Patent: July 21, 1998
    Assignee: Eastman Kodak Company
    Inventors: Edward P. Furlani, Syamal K. Ghosh, Dilip K. Chatterjee
  • Patent number: 5779969
    Abstract: A method for fabricating a multiwound microcoil embedded in a ceramic substrate including the steps of forming a sacrificial multiwound microcoil, having a melting temperature greater than the sintering temperature of the ceramic material to be used as the ceramic substrate by wrapping a first sacrificial coil winding in a helical fashion on the midsection of a sintered ceramic bar thereby forming a one winding sacrificial coil structure; wrapping a first layer of tape cast ceramic material around the midsection of said one winding sacrificial coil structure thereby forming a first coated one winding sacrificial coil structure; wrapping a second sacrificial coil winding in a helical fashion on the midsection of said first coated one winding sacrificial coil structure thereby forming a two winding sacrificial coil structure.
    Type: Grant
    Filed: June 20, 1997
    Date of Patent: July 14, 1998
    Assignee: Eastman Kodak Company
    Inventors: Dilip K. Chatterjee, Edward P. Furlani, Syamal K. Ghosh
  • Patent number: 5776408
    Abstract: A method of engraving pre-sintered ceramic articles involves providing a source of laser energy for forming a polyester mask having a predetermined spiral pattern etched therein. To form the polyester mask, means are provided for computationally communicating a predetermined engraving pattern to the source of laser energy. Once the polyester mask is formed, it is overlaid onto the ceramic article forming a laminate and the laminate is bombarded with a hard alumina grit to form the spiral pattern in the ceramic article. After the ceramic article is engraved with the predetermined spiral pattern, the polyester mask is removed exposing an engraved ceramic article.
    Type: Grant
    Filed: August 23, 1996
    Date of Patent: July 7, 1998
    Assignee: Eastman Kodak Company
    Inventors: Syamal K. Ghosh, Dilip K. Chatterjee, Badhri Narayan
  • Patent number: 5771764
    Abstract: A method of cutting, slicing or perforating photographic imaging elements using certain cutting tools is disclosed. The cutting tool material includes zirconia and yttria at a molar ratio of yttria to zirconia from about 0.5:99.5 to about 5:95. The cutting tool is essentially a tetragonal crystal phase grain for the interior in a surface of cubic crystal phase grain or monoclinic crystal phase grain. This provides a hard, tough outer surface with a tough core. The cutting tool material can also be a composite of zirconia-alumina with or without surface modification.
    Type: Grant
    Filed: September 16, 1997
    Date of Patent: June 30, 1998
    Assignee: Eastman Kodak Company
    Inventors: Dilip K. Chatterjee, Syamal K. Ghosh, Dennis J. Eichorst
  • Patent number: 5762485
    Abstract: An improved gear micropump (10) for delivering corrosive materials, particularly photographic materials, such as dyes and emulsions, has a pair of intermeshing gears (16,18) rotatably mounted on zirconia ceramic shafts (24,26). The ceramic shafts of the invention may be formed from zirconia and zirconia composite materials. The gear micropump (10) having the zirconia ceramic shafts (24,26) eliminates pulsation during fluid delivery and is resistant to wear and abrasion. Moreover the zirconia ceramic shafts (24,26) are strongly resistant to chemicals like photographic emulsions and dyes and, therefore, do not contaminate product with corrosive materials.
    Type: Grant
    Filed: September 6, 1996
    Date of Patent: June 9, 1998
    Assignee: Eastman Kodak Company
    Inventors: Syamal K. Ghosh, Dilip K. Chatterjee, David Alan Ash
  • Patent number: 5739942
    Abstract: A microceramic optical shutter includes a unitary ceramic body which has been formed with first and second internal cavities, a coil structure formed in the first internal cavity and a ferromagnetic stator formed in the second internal cavity and disposed in operative relationship with the coil structure.
    Type: Grant
    Filed: February 12, 1997
    Date of Patent: April 14, 1998
    Assignee: Eastman Kodak Company
    Inventors: Edward P. Furlani, Syamal K. Ghosh, Dilip K. Chatterjee
  • Patent number: 5738446
    Abstract: An air lubricated hydrodynamic bearing assemblage has a ceramic body and a ceramic shaft each made of tetragonal zirconium ceramic material. The bearing has flange portions on opposite ends a a generally cylindrical body. At least one of the flange portions has air channels formed therein in fluid communications with air inlet ports formed in the bearing body.
    Type: Grant
    Filed: August 23, 1996
    Date of Patent: April 14, 1998
    Assignee: Eastman Kodak Company
    Inventors: Syamal K. Ghosh, Dilip K. Chatterjee, Theodore Richard Kolb
  • Patent number: 5733588
    Abstract: An improved molding equipment includes highly efficient, durable, and wear and abrasion resistant sliding elements. In particular, the equipment has a feeder box and a ware plate arranged for sliding contact each comprising high precision tetragonal zirconia polycrystal (TZP) ceramic or alternatively zirconia-alumina ceramic composite. Moreover, a die cavity arranged along the ware plate has a ceramic die retaining element to enable high efficiency as well as wear and abrasion resistant sliding contact with the feeder box.
    Type: Grant
    Filed: October 28, 1996
    Date of Patent: March 31, 1998
    Assignee: Eastman Kodak Company
    Inventors: Dilip K. Chatterjee, Syamal K. Ghosh
  • Patent number: 5730928
    Abstract: A method of making a hydrodynamic ceramic bearing includes the steps of providing ceramic powder comprising a first concentration of particulate aluminum oxide and a second concentration of particulate zirconium oxide alloy. The zirconium oxide alloy consists essentially of zirconium oxide and a the group consisting of MgO, CaO, Y.sub.2 O.sub.3, Sc.sub.2 O.sub.3, and rare earth oxides. The zirconium oxide alloy has a concentration of the secondary oxide of, in the case of Y.sub.2 O.sub.3, about 0.5 to about 5 mole percent; in the case of MgO, about 0.1 to about 1.0 mole percent, in the case of CeO.sub.2, about 0.5 to about 15 mole percent, in the case of Sc.sub.2 O.sub.3, about 0.5 to about 7.0 mole percent and in the case of CaO from about 0.5 to about 5 mole percent, relative to the total of the zirconium oxide alloy, the compacting further comprising forming a blank. A mold is provided for receiving and processing the ceramic powder thereby forming a ceramic billet.
    Type: Grant
    Filed: August 23, 1996
    Date of Patent: March 24, 1998
    Assignee: Eastman Kodak Company
    Inventors: Syamal K. Ghosh, Dilip K. Chatterjee, David Alan Ash
  • Patent number: 5730929
    Abstract: The present invention is a method for injection molding fine particulate inorganic materials which includes the steps of, compounding a particulate inorganic material and a magnesium-X silicate, wherein X represents lithium, sodium, potassium or other monovalent ion, containing binder, injecting the compounded material at low pressure and ambient temperature into a mold to form a green part, and sintering the green part to form the final molded part.
    Type: Grant
    Filed: March 6, 1997
    Date of Patent: March 24, 1998
    Assignee: Eastman Kodak Company
    Inventors: Debasis Majumdar, Dilip K. Chatterjee, Lisa B. Todd
  • Patent number: 5726110
    Abstract: The present invention is a ceramic article of magnesium-X silicate, wherein X represents lithium, sodium, potassium or other monovalent ion from about 0.1 to 2 weight percent, and yttria stabilized zirconia and alumina composite from about 99.9 to 98 weight percent wherein the yttria stabilized zirconia has a molar ratio of yttria to zirconia of from 0.5:99.5 to 5:95 and the alumina comprises from 0.1 to 50 percent of the yttria stabilized zirconia and alumina composite.
    Type: Grant
    Filed: March 6, 1997
    Date of Patent: March 10, 1998
    Assignee: Eastman Kodak Company
    Inventors: Debasis Majumdar, Dilip K. Chatterjee, Robert J. Kress
  • Patent number: 5723393
    Abstract: The present invention is a ceramic article of magnesium-X silicate, wherein X represents lithium, sodium or, from about 0.1 to 2 weight percent, and yttria stabilized zirconia from about 99.9 to 98 weight percent wherein the yttria stabilized zirconia has a molar ratio of yttria to zirconia of from 0.5:99:5 to 5:95.
    Type: Grant
    Filed: March 6, 1997
    Date of Patent: March 3, 1998
    Assignee: Eastman Kodak Company
    Inventors: Debasis Majumdar, Dilip K. Chatterjee, Syamal K. Ghosh