Patents by Inventor Roger Lok

Roger Lok 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: 5945270
    Abstract: This invention relates to a silver halide photographic element comprising a support and a silver halide emulsion layer, the emulsion layer comprising an organomercapto Au(I) complex having the formula?(M--SOL).sub.n --A--S--Au--S--A--(SOL--M).sub.n !Mwherein M is a cationic counterion;SOL is a solubilizing group:A is a substituted or unsubstituted divalent organic linking group;and n is 1 to 4 and wherein the compound is symmetrical.It further relates to a method of preparing a silver halide emulsion utilizing said organomercapto Au(I) complexes.
    Type: Grant
    Filed: November 6, 1997
    Date of Patent: August 31, 1999
    Assignee: Eastman Kodak Company
    Inventors: Roger Lok, Weimar W. White, Brian P. Cleary
  • Patent number: 5939245
    Abstract: This invention relates to a silver halide photographic element comprising a support and a silver halide emulsion layer, the emulsion layer comprising a Au(I) compound having the formula wherein Z is a substituted or unsubstituted alkyl, aryl, alkylaryl, or heterocyclic group; and R.sub.1, R.sub.2, R.sub.3 and R.sub.4 are independently substituted or unsubstituted alkyl, aryl, alkylaryl, or heterocyclic groups, or one or both of R.sub.1 and R.sub.2 or R.sub.3 and R.sub.4, may independently combine to form a nitrogen containing ring with the nitrogen to which they are attached.
    Type: Grant
    Filed: December 23, 1997
    Date of Patent: August 17, 1999
    Assignee: Eastman Kodak Company
    Inventors: Roger Lok, Weimar W. White, Melanie W. Marshall
  • Patent number: 5914226
    Abstract: A silver halide photographic element comprising a silver halide emulsion which is greater than 50 mole % silver chloride, said emulsion being in reactive association with a dithiolone 1-oxide compound represented by the following formula: ##STR1## wherein b is C(O), C(S), C(Se), CH.sub.2 or (CH.sub.2).sub.2, and R.sup.1 and R.sup.2 are independently H, or aliphatic, aromatic or heterocyclic groups, alkoxy groups, hydroxy groups, halogen atoms, aryloxy groups, alkylthio groups, arylthio groups, acyl groups, sulfonyl groups, acyloxy groups, carboxyl groups, cyano groups, sulfo groups, or amino groups, or R.sup.1 and R.sup.2 together represent the atoms necessary to form a five or six-membered ring or a multiple ring system; and a sulfinate compound.
    Type: Grant
    Filed: September 11, 1997
    Date of Patent: June 22, 1999
    Assignee: Eastman Kodak Company
    Inventor: Roger Lok
  • Patent number: 5912112
    Abstract: A photographic element comprising a support having situated thereon a silver halide emulsion layer, said emulsion layer comprising a compound of the formula:Z--S--Au(I)--S--Q (I)whereinZ represents an alkyl, aryl, or heterocyclic group; andQ represents a heterocyclic group wherein S and Q together represent a mesoionic group.
    Type: Grant
    Filed: March 5, 1998
    Date of Patent: June 15, 1999
    Assignee: Eastman Kodak Company
    Inventors: Roger Lok, Weimar W. White, Melanie W. Marshall
  • Patent number: 5912111
    Abstract: This invention relates to a silver halide photographic element comprising a support and a silver halide emulsion layer, the emulsion layer comprising a Au(I) compound having the formula ##STR1## wherein Z is a substituted or unsubstituted alkyl, aryl, alkylaryl, or heterocyclic group; and R.sub.1, R.sub.2, R.sub.3 and R.sub.4 are independently substituted or unsubstituted alkyl, aryl, alkylaryl, or heterocyclic groups, or one or both of R.sub.1 and R.sub.2 or R.sub.3 and R.sub.4, may independently combine to form a nitrogen containing ring with the nitrogen to which they are attached.
    Type: Grant
    Filed: February 18, 1998
    Date of Patent: June 15, 1999
    Assignee: Eastman Kodak Company
    Inventors: Roger Lok, Weimar W. White, Melanie W. Marshall
  • Patent number: 5792601
    Abstract: A radiation sensitive emulsion is disclosed containing iridium doped composite silver halide grains comprised of (a) host portions having an average aspect ratio of less than 1.3 and consisting essentially of monodisperse silver iodochloride grains containing from 0.05 to 3 mole percent iodide, based on total silver forming the host portions, with maximum iodide concentrations located nearer the surface of the host portions than their center and (b) epitaxially deposited portions containing the iridium dopant and silver bromide accounting for from 0.1 to 5 mole percent of total silver forming the composite grains.The emulsions are prepared by (a) first providing an emulsion containing grains which form the host portions of the grains and (b) modifying the performance properties of the host grains by a combination of silver bromide addition, iridium dopant incorporation and antifoggant addition, in which, prior to antifoggant addition, silver bromide in the amount of from 0.1 to 5.
    Type: Grant
    Filed: July 29, 1996
    Date of Patent: August 11, 1998
    Assignee: Eastman Kodak Company
    Inventors: James Lawrence Edwards, Benjamin Teh-Kung Chen, Eric Leslie Bell, Roger Lok
  • Patent number: 5756278
    Abstract: The invention relates to a silver halide photographic emulsion comprising a silver halide emulsion wherein the grains of said emulsion comprise silver chloride said grains are sensitized with a water soluble gold(I) or (III) compound, and said emulsion further comprises a dithiolone dioxide.
    Type: Grant
    Filed: June 30, 1997
    Date of Patent: May 26, 1998
    Assignee: Eastman Kodak Company
    Inventor: Roger Lok
  • Patent number: 5736310
    Abstract: Radiation sensitive emulsions are disclosed comprised of silver iodochloride grains having three pairs of equidistantly spaced parallel {100} crystal faces and containing from 0.05 to 3 mole percent iodide, based on total silver, in a controlled, non-uniform iodide distribution forming a core containing at least 50 percent of total silver, a surface shell, and a sub-surface shell that contains a maximum iodide concentration and provides, when the emulsion is exposed to 390 nm electromagnetic radiation at 10.degree. K., stimulated fluorescent emissions in the range of from 450 to 470 nm and at 500, the stimulated fluorescent emission in the range of from 450 to 470 nm having a peak intensity more than twice the stimulated fluorescent emission intensity at 500 nm.
    Type: Grant
    Filed: May 17, 1996
    Date of Patent: April 7, 1998
    Assignee: Eastman Kodak Company
    Inventors: Benjamin Teh-Kung Chen, James Lawrence Edwards, Roger Lok, Sanford Howard Ehrlich
  • Patent number: 5726005
    Abstract: A photographic print element is disclosed having a reflective support and at least one image recording emulsion layer unit containing cube-like silver iodochloride grains containing from 0.05 to 3 mole percent iodide, based on total silver, in a controlled, non-uniform iodide distribution forming a core, an iodide-free surface shell having a thickness of greater than 50 .ANG., and a sub-surface shell that contains a maximum iodide concentration.
    Type: Grant
    Filed: May 17, 1996
    Date of Patent: March 10, 1998
    Assignee: Eastman Kodak Company
    Inventors: Benjamin Teh-Kung Chen, James Lawrence Edwards, Roger Lok, Sanford Howard Ehrlich
  • Patent number: 5719019
    Abstract: Room-light handleable direct silver halide emulsions exhibit a broadened Dmin window when certain nitro-substituted aryl- or heteroaryl-containing imidazoles are included. These imidazoles act as excellent rereversal and Dmin suppressants. Photographic elements are prepared from these emulsions that can be handled in room-light if desired.
    Type: Grant
    Filed: July 31, 1996
    Date of Patent: February 17, 1998
    Assignee: Eastman Kodak Company
    Inventors: Gaile Antoinette Janusonis, Roger Lok
  • Patent number: 5700631
    Abstract: A photographic element is provided comprising a support having situated thereon a silver halide emulsion layer, the emulsion layer comprising a compound of the formula:Z--SO.sub.2 S--Au(I)--L (I)whereinZ represents an alkyl, aryl, or heterocyclic group; andL represents a thioether, selenoether or telluroether containing ligand.
    Type: Grant
    Filed: June 28, 1996
    Date of Patent: December 23, 1997
    Assignee: Eastman Kodak Company
    Inventors: Roger Lok, Weimar Weatherly White
  • Patent number: 5693460
    Abstract: This invention provides a silver halide photographic element comprising a silver halide emulsion in reactive association with a dioxide compound represented by the following formula: ##STR1## wherein b is C(O), C(S), C(Se), CH2 or (CH2)2; and R.sup.1 and R.sup.2 are independently H, or aliphatic, aromatic or heterocyclic groups, or R.sup.1 and R.sup.2 together represent the atoms necessary to form a five or six-membered ring or a multiple ring system. This invention further provides a method of making silver halide emulsions containing the dioxide compounds.
    Type: Grant
    Filed: June 24, 1996
    Date of Patent: December 2, 1997
    Assignee: Eastman Kodak Company
    Inventor: Roger Lok
  • Patent number: 5686236
    Abstract: A photographic element comprising a support having situated thereon a silver halide emulsion layer, said emulsion layer comprising a compound of the formula:Z--SO.sub.2 S--Au(I)--SQ (I)whereinZ represents an alkyl, aryl, or heterocyclic group; andQ represents an aryl or heterocyclic group.
    Type: Grant
    Filed: January 2, 1997
    Date of Patent: November 11, 1997
    Assignee: Eastman Kodak Company
    Inventors: Roger Lok, Weimar Weatherly White
  • Patent number: 5677119
    Abstract: This invention provides a silver halide photographic element comprising a silver halide emulsion in reactive association with a dithiolone 1-oxide compound represented by the following formula: ##STR1## wherein b is C(O), C(S), C(Se), CH.sub.2 or (CH.sub.2).sub.2, and R.sup.1 and R.sup.2 are independently H, or aliphatic, aromatic or heterocyclic groups, alkoxy groups, hydroxy groups, halogen atoms, aryloxy groups, alkylthio groups, arylthio groups, acyl groups, sulfonyl groups, acyloxy groups, carboxyl groups, cyano groups, sulfo groups, or amino groups, or R.sup.1 and R.sup.2 together represent the atoms necessary to form a five or six-membered ring or a multiple ring system. It further provides a method of making a silver halide emulsion containing a dithiolone 1-oxide compound.
    Type: Grant
    Filed: October 29, 1996
    Date of Patent: October 14, 1997
    Assignee: Eastman Kodak Company
    Inventor: Roger Lok
  • Patent number: 5670307
    Abstract: A silver halide photographic element comprising a silver halide emulsion which is greater than 50 mole % silver chloride, said emulsion being in reactive association with a dioxide compound represented by the following formula: ##STR1## wherein b is C(O), C(S), C(Se), CH.sub.2 or (CH.sub.2).sub.2 ; and R.sup.1 and R.sup.2 are independently H, or aliphatic, aromatic or heterocyclic groups, or R.sup.1 and R.sup.2 together represent the atoms necessary to form a five or six-membered ring or a multiple ring system; and a sulfinate compound.
    Type: Grant
    Filed: September 27, 1996
    Date of Patent: September 23, 1997
    Assignee: Eastman Kodak Company
    Inventor: Roger Lok
  • Patent number: 5652090
    Abstract: This invention provides a silver halide photographic element comprising a silver halide emulsion in reactive association with a dithiolone compound represented by the following formula: ##STR1## wherein R.sup.1 and R.sup.2 are independently H, or aliphatic, aromatic or heterocyclic groups, alkoxy groups, hydroxy groups, halogen atoms, aryloxy groups, alkylthio groups, arylthio groups, acyl groups, sulfonyl groups, acyloxy groups, carboxyl groups, cyano groups, sulfo groups, or amino groups, or R.sup.1 and R.sup.2 together represent the atoms necessary to form a five or six-membered ring or a multiple ring system. This invention further provides a method of making silver halide emulsions containing the dithiolone compounds.
    Type: Grant
    Filed: March 15, 1996
    Date of Patent: July 29, 1997
    Assignee: Eastman Kodak Company
    Inventor: Roger Lok
  • Patent number: 5620841
    Abstract: A photographic element comprising a support having situated thereon a silver halide emulsion layer, said emulsion layer comprising a compound of the formula:Z--SO.sub.2 S--Au(I)--SQ (I)whereinZ represents an alkyl, aryl, or heterocyclic group; andQ represents an aryl or heterocyclic group.
    Type: Grant
    Filed: June 28, 1996
    Date of Patent: April 15, 1997
    Assignee: Eastman Kodak Company
    Inventors: Roger Lok, Weimar W. White
  • Patent number: 5605789
    Abstract: The invention provides a radiation sensitive emulsion comprised of a dispersing medium and silver iodochloride grainsWHEREIN the silver iodochloride grainsare partially bounded by {100} crystal faces satisfying the relative orientation and spacing of cubic grains andcontain from 0.05 to 1 mole percent iodide, based on total silver, with maximum iodide concentrations located nearer the surface of the grains than their centerand wherein said emulsion further comprises an iodonium salt represented by formula (I) [R.sub.1 I.sup.+ R.sub.2 ] Q.sup.-wherein R.sub.1, R.sub.2, may be independently substituted or non-substituted alkyl, aryl, alkylaryl, but not oxygen, or together R.sub.1 and R.sub.2 may form carbocyclic, heterocyclic, aromatic, or heteroaromatic rings and Q is an anion.
    Type: Grant
    Filed: December 22, 1994
    Date of Patent: February 25, 1997
    Assignee: Eastman Kodak Company
    Inventors: Benjamin T. K. Chen, Roger Lok
  • Patent number: 5601970
    Abstract: This invention provides a photographic element comprising a support having thereon a silver halide emulsion layer which is greater than about 50 mole % silver chloride, wherein the emulsion layer contains a thiophosphate ester of the structure: ##STR1## wherein R.sup.1, R.sup.2 and R.sup.3 are independently selected from the group consisting of an aliphatic, carbocyclic or heterocyclic group.
    Type: Grant
    Filed: January 3, 1995
    Date of Patent: February 11, 1997
    Assignee: Eastman Kodak Company
    Inventor: Roger Lok
  • Patent number: 5576432
    Abstract: A process of preparing a dihydropyrimidine compound of the structure (I): ##STR1## wherein R.sup.1 and R.sup.2 are bonded together to form an aromatic or heterocyclic ring, which may be substituted or unsubstituted, or are individually selected from the group consisting of hydrogen, or a substituted or unsubstituted aliphatic, carbocyclic, or heterocyclic group;R.sup.3, R.sup.4 and R.sup.5 are individually selected from the group consisting of hydrogen or a substituted or unsubstituted aliphatic, carbocyclic or heterocyclic group; andX represents the atoms necessary to form a 5 or 6 membered heterocyclic ring, and is selected from the group consisting of oxygen, sulfur, selenium, ##STR2## wherein R.sup.6, R.sup.7, and R.sup.8 are individually selected from the group consisting of a substituted or unsubstituted aliphatic, carbocyclic or heterocyclic group; comprising combining a compound (A) of the structure: ##STR3## wherein X, R.sup.1, R.sup.2, R.sup.3, R.sup.4, R.sup.5, R.sup.6, R.sup.7, and R.sup.
    Type: Grant
    Filed: December 23, 1994
    Date of Patent: November 19, 1996
    Assignee: Eastman Kodak Company
    Inventors: Roger Lok, Antony J. Williams