Patents by Inventor Pranab Bagchi
Pranab Bagchi 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: 5916358Abstract: The invention is related to an aqueous ink composition comprising water, a coloring agent, and solid surfactant particles wherein said solid particles comprise a mixture of at least two surfactants with very low water solubility and with melting points between 40.degree. C. and 90.degree. C.Type: GrantFiled: December 30, 1996Date of Patent: June 29, 1999Assignee: Eastman Kodak CompanyInventors: Pranab Bagchi, Ravi Sharma, Constance N. Anagnostopoulos, Gilbert A. Hawkins, John A. Lebens, Thierry Vachette, James M. Chwalek, David S. Ross
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Patent number: 5896155Abstract: A liquid ink, drop on demand page-width printhead comprises a semiconductor substrate, a plurality of drop-emitter nozzles fabricated on the substrate; an ink supply manifold coupled to the nozzles; pressure means for subjecting ink in the manifold to a pressure above ambient pressure causing a meniscus to form in each nozzle; a means for applying heat to the perimeter of the meniscus in predetermined selectively addressed nozzles; a means for controlling the volume of poised drops in the selectively addressed nozzles; and a means for transferrring the poised drops onto the recording media.Type: GrantFiled: February 28, 1997Date of Patent: April 20, 1999Assignee: Eastman Kodak CompanyInventors: John Andrew Lebens, James Michael Chwalek, Pranab Bagchi
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Patent number: 5741633Abstract: The invention describes silver halide packet emulsion grains or crystals that are conventionally precipitated using gelatin of a given isoelectric pH, surrounded by a layer of gelatin-grafted-polymer particles wherein the grafted gelatin has a different isoelectric pH and the said gelatin-grafted-polymer particles are optionally chemically bonded to the gelatin surrounding the silver halide microcrystals. Such packet emulsions can form the basis for a mixed-packet color photographic system.Type: GrantFiled: June 7, 1995Date of Patent: April 21, 1998Assignee: Eastman Kodak CompanyInventors: Mark Anthony Whitson, John Derek Lewis, Tienteh Chen, Thomas Joseph Dannhauser, Pranab Bagchi
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Patent number: 5726693Abstract: A liquid ink, drop-on-demand pagewidth printhead including a semiconductor substrate, a plurality of drop-emitter nozzles fabricated on the substrate; an ink supply manifold coupled to the nozzles; pressure element for subjecting ink in the manifold to a pressure above ambient pressure; a drop selection device for selectively addressing predetermined nozzles, and drop separation device to transfer ink selected drops from selected nozzles to a print region. A surface tension reducing agent for each nozzle is provided from a supply separate from the ink and integrated into the printhead. An increase in ink drop protrusion from the nozzle surface differentiates selected drops from non-selected drops.Type: GrantFiled: July 22, 1996Date of Patent: March 10, 1998Assignee: Eastman Kodak CompanyInventors: Ravi Sharma, Gilbert Allan Hawkins, Pranab Bagchi, David Lee Clark
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Patent number: 5716642Abstract: This invention describes the preparation of nanoparticulate pharmaceutical agent dispersion via a process that comprises the dissolution of the said pharmaceutical agent in an alkaline solution and then neutralizing the said solution with an acid in the presence of suitable surface-modifying, surface-active agents to form a fine particle dispersion of the said pharmaceutical agent. A combination of surface active surface modifying agents comprising a nonionic surface active substance and an anionic surface active material having a chemical structure which is at least on a molecular basis 75% similar to the pharmaceutical agent is used. This process is preferably followed by steps of diafiltration clean-up of the dispersion and then concentration of it to a desired level. This process of dispersion preparation leads to microcrystalline particles of Z-average diameters smaller than 400 nm as measured by photon correlation spectroscopy.Type: GrantFiled: January 10, 1995Date of Patent: February 10, 1998Assignee: Nano Systems L.L.C.Inventors: Pranab Bagchi, Gregory L. McIntire, John R. Minter
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Patent number: 5693461Abstract: This invention describes the composition and method of preparation of heteroflocculated packet emulsion clusters containing a light sensitive and selectively photosensitized silver halide emulsion particles and particles of photographic agents such as dye-forming coupler particles. The silver halide emulsion particles are associated with a layer of adsorbed peptizing gelatin with an isoelectric pH of P.sub.1 and the grafted gelatin of the gelatin-grafted-polymer particles comprising the photographic agent has an isoelectric pH of P.sub.2 such that P.sub.1 is different than P.sub.2. At least one of the peptizing and grafted gelatins is an isoing gelatin which is sufficiently derivatized to remove ionic groups thereof such that approaching the isoelectric pH in an aqueous solution of the isoing gelatin causes massive heteroflocculation.Type: GrantFiled: March 21, 1995Date of Patent: December 2, 1997Assignee: Eastman Kodak CompanyInventors: Pranab Bagchi, Tienteh Chen, Thomas Joseph Dannhauser, John Derek Lewis, Mark Anthony Whitson
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Patent number: 5665331Abstract: This invention describes the coprecipitation of nanoparticulate pharmaceutical agent dispersion via a process that comprises the dissolution of the said pharmaceutical agent in combination with a crystal growth modifier (CGM) in an alkaline solution and then neutralizing the said solution with an acid in the presence of suitable surface-modifying surface-active agent or agents to form a fine particle dispersion of the said pharmaceutical agent, followed by steps of diafiltration clean-up of the dispersion and then concentration of it to a desired level. This process of dispersion preparation leads to microcrystalline particles of Z-average diameters smaller than 400 nm as measured by photon correlation spectroscopy. Various modification of precipitation schemes are described, many of which are suitable for large-scale manufacture of these agent dispersions.Type: GrantFiled: January 10, 1995Date of Patent: September 9, 1997Assignee: NanoSystems L.L.C.Inventors: Pranab Bagchi, Raymond P. Scaringe, H. William Bosch
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Patent number: 5662883Abstract: It has been known that administration of pharmaceutical agents (both diagnostic and therapeutic) with poor water solubility in the form of particles less than 400 nm in diameter produces agent formulation with increased bioavailibility. Bioavailability being proportional to the surface area, increases with reduction of particle size of the dispersed agent. We have discovered that chemical derivatization of certain photographic coupler molecules with chemical moiety that are capable of functioning as pharmaceutical agents (both diagnostic and therapeutic) is amenable to the preparation of nanoparticulate pharmaceutical agent dispersions via a process that comprises the dissolution of the said pharmaceutical agent in an alkaline solution and then neutralizing the said solution with an acid in the presence of a suitable surface-modifying, surface-active agent to form an ultra fine particle dispersion of the said pharmaceutical agent.Type: GrantFiled: January 10, 1995Date of Patent: September 2, 1997Assignee: NanoSystems L.L.C.Inventors: Pranab Bagchi, Robert C. Stewart, Gregory L. McIntire, John R. Minter
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Patent number: 5610002Abstract: This invention describes gelatin thickening compounds for photographic coating melts with the general structure: ##STR1## wherein: A is an aromatic or heteroaromatic group;X is SO.sub.3 M or CO.sub.2 MM is H or an alkali metal, ammonium or pyridinium ion; each R1 and R2 is independently an alkyl or substituted alkyl group, each alkyl group being straight or branched chain and having 1 to 30 carbon atoms;each R3 and R4 is independently H or an alkyl or substituted alkyl group, each alkyl group being straight or branched chain and having 1 to 30 carbon atoms;each of a, b, c and e is independently 0, 1, 2 or 3, with the proviso that a+b+c+e is at least 1; andd is 1, 2, or 3;with the further proviso that when A is phenyl, X is SO.sub.3 M, d is 1 and any one of a, c, or e is 1, the sum of a+b+c+e is at least 2; and wherein there is a substantial absence of a compound containing one or more --SO.sub.2.sup.- groups in the composition.Type: GrantFiled: November 13, 1995Date of Patent: March 11, 1997Assignee: Eastman Kodak CompanyInventors: Robert J. Ross, Pranab Bagchi, Richard W. Connelly
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Patent number: 5591568Abstract: This invention provides composition and method to overcome the very high viscosity of prior small-particle dispersions when admixed with gelatin in aqueous solution for coating a photographic film element.The invention is generally accomplished by the utilization of a second surfactant in the melt formulated by the admixture of the small-particle dispersion and the gelatin solution. The surfactants of this invention, that is, utilized to control the rheology of such said melts, have the following general structure: ##STR1## wherein n=5 to 20 andx=1 to 4.Type: GrantFiled: September 6, 1994Date of Patent: January 7, 1997Assignee: Eastman Kodak CompanyInventors: Pranab Bagchi, James L. Edwards, Danuta Gibson, Thomas A. Rosiek, Brian Thomas, Vincent J. Flow, III
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Patent number: 5565309Abstract: The invention creates a selective oxygen barrier around individual coupler or other photographically active particles by surrounding each particle with a layer of water applicable oxygen barrier polymer such as polyvinyl alcohol (PVA), which will also act as a steric barrier to coalescence of the particles. Photographic products formed with such materials are more dye stable. The dispersions of this invention are prepared by mechanical milling or homogenization procedures.Type: GrantFiled: August 18, 1994Date of Patent: October 15, 1996Assignee: Eastman Kodak CompanyInventors: Pranab Bagchi, Vincent J. Flow, III, Alberto M. Martinez
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Patent number: 5560932Abstract: This invention describes the preparation of nanoparticulate pharmaceutical agent dispersion via a process that comprises the dissolution of the said pharmaceutical agent in an alkaline solution and then neutralizing the said solution with an acid in the presence of a suitable surface-modifying, surface-active agent to form a fine particle dispersion of the said pharmaceutical agent. This can be preferably followed by steps of diafiltration clean-up of the dispersion and then concentration of it to a desired level. This process of dispersion preparation leads to microcrystalline particles of Z-average diameters smaller than 400 nm as measured by photon correlation spectroscopy. Various modification of precipitation schemes are described, many of which are suitable for large-scale manufacture of these agent dispersions.Type: GrantFiled: January 10, 1995Date of Patent: October 1, 1996Assignee: Nano Systems L.L.C.Inventors: Pranab Bagchi, Piotr H. Karpinski, Gregory L. McIntire
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Patent number: 5543283Abstract: The invention describes silver halide packet emulsion grains or crystals that are conventionally precipitated using gelatin of a given isoelectric pH, surrounded by a layer of gelatin-grafted-polymer particles wherein the grafted gelatin has a different isoelectric pH and the said gelatin-grafted-polymer particles are optionally chemically bonded to the gelatin surrounding the silver halide microcrystals. Such packet emulsions can form the basis for a mixed-packet color photographic system.Type: GrantFiled: November 30, 1994Date of Patent: August 6, 1996Assignee: Eastman Kodak CompanyInventors: Mark A. Whitson, John D. Lewis, Tienteh Chen, Thomas J. Dannhauser, Pranab Bagchi
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Patent number: 5536630Abstract: The invention provides a method of nucleating silver halide particles wherein said nucleation is carried out in the presence of acid processed ossein (APO) gelatin or chain-extended acid processed ossein (CE-APO) gelatin and the composition formed therefrom.Type: GrantFiled: September 26, 1994Date of Patent: July 16, 1996Assignee: Eastman Kodak CompanyInventors: Pranab Bagchi, Melvin D. Sterman, Jacob I. Cohen
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Patent number: 5503972Abstract: This invention describes the use of gelatin-grafted-polymer particles as peptizers for the preparation of silver halide photographic emulsions, whereby the gelatin-grafted-polymer particles remain attached to the AgX crystals after preparation of the emulsions. In an embodiment of this invention, the core polymer particles are loaded with photographically useful agents. When the photographic agent is a dye-forming coupler, multicolor mixed-packet systems can be constructed using the packet emulsions prepared in the manner of this invention.Type: GrantFiled: April 13, 1995Date of Patent: April 2, 1996Assignee: Eastman Kodak CompanyInventors: John D. Lewis, Mark A. Whitson, Thomas J. Dannhauser, Tienteh Chen, Pranab Bagchi
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Patent number: 5491052Abstract: It has been discovered that when polyalkylene oxide compounds or block polymeric or block oligomeric surface active compounds comprising at least a polyoxypropylene (POP) block and a polyoxyethylene (POE) block are added to conventional dispersions of yellow couplers (that is dispersions in which the dispersed particles have a particle size of 0.1 to 0.6 .mu.m), such dispersions in a coated silver halide photographic element produce substantially higher dye yield compared to the conventional dispersion without any additive. Further, the yellow dye formed from such dispersions containing the addenda of this invention are substantially more light stable compared to dispersions that does not contain such addenda.The invention is carried out just by adding required amounts of the said polyoxyethylene (POE)--polyoxypropylene (POP) compound to a preformed milled coupler dispersion prior to coating the photographic element.Type: GrantFiled: June 7, 1995Date of Patent: February 13, 1996Assignee: Eastman Kodak CompanyInventors: James P. Van Meter, Pranab Bagchi, Brian Thomas, Thomas A. Rosiek
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Patent number: 5441865Abstract: This invention describes the use of gelatin-grafted-polymer particles as peptizers for the preparation of silver halide photographic emulsions, whereby the gelatin-grafted-polymer particles remain attached to the AgX crystals after preparation of the emulsions. In an embodiment of this invention, the core polymer particles are loaded with photographically useful agents. When the photographic agent is a dye-forming coupler, multicolor mixed-packet systems can be constructed using the packet emulsions prepared in the manner of this invention.Type: GrantFiled: January 7, 1993Date of Patent: August 15, 1995Assignee: Eastman Kodak CompanyInventors: John D. Lewis, Mark A. Whitson, Thomas J. Dannhauser, Tienteh Chen, Pranab Bagchi
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Patent number: 5426020Abstract: This invention describes the use of surfactants of the following types:Type A--Surfactant comprising 6 to 22 carbon atom hydrophobic tail with one or more attached hydrophilic chains comprising at least 8 oxyethylene and/or glycidyl ether groups that may or may not be terminated with a negative charge such as a sulfate group,Type B--Block oligomeric surfactants comprising hydrophobic polyoxypropylene blocks (A) and hydrophilic polyoxyethylene blocks (B) joined in the manner of A--B--A, B--A--B, A--B, (A--B.sub.n .tbd.G.tbd.(B--A).sub.n, or (B--A).sub.n .tbd.G(A--B).sub.n, where G is a connective organic moiety and n is between 1 and 3,Type C--Sugar surfactants, comprising between one to three 6 to 22 carbon atom hydrophobic tail with one or more attached hydrophilic mono or oligosaccharidic chains that may or may not be terminated by a negatively charged group such as a sulfate group.Type: GrantFiled: August 31, 1993Date of Patent: June 20, 1995Assignee: Eastman Kodak CompanyInventors: Pranab Bagchi, Melvin M. Kestner
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Patent number: 5399480Abstract: The invention describes silver halide packet emulsion grains or crystals that are conventionally precipitated using gelatin of a given isoelectric pH, surrounded by a layer of gelatin-grafted-polymer particles wherein the grafted gelatin has a different isoelectric pH and the said gelatin-grafted-polymer particles are optionally chemically bonded to the gelatin surrounding the silver halide microcrystals. Such packet emulsions can form the basis for a mixed-packet color photographic system.Type: GrantFiled: September 14, 1993Date of Patent: March 21, 1995Assignee: Eastman Kodak CompanyInventors: Mark A. Whitson, John D. Lewis, Tienteh Chen, Thomas J. Dannhauser, Pranab Bagchi
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Patent number: 5397695Abstract: Useful materials for diagnostic tests, affinity chromatography, enzymatic reactions and immunoassays are prepared by covalently attaching reactive compounds containing reactive amino or sulfhydryl groups to polymeric particles having pendant carboxyl groups on the outer surfaces. Such reactive compounds include biologically reactive species, such as enzymes, polypeptides and proteins. This attachment is carried out using carbamoylonium compounds which react with the carboxyl groups to form intermediate reactive groups which then react with the amino or sulfhydryl groups to form a covalent linkage between particle and reactive compound. A kit comprises polymeric particles having carboxyl groups on the outer surfaces, and a carbamoylonium compound.Type: GrantFiled: June 29, 1989Date of Patent: March 14, 1995Assignee: Eastman Kodak CompanyInventors: Richard C. Sutton, Susan J. Danielson, Pranab Bagchi, Patricia M. Scensny