Patents by Inventor Philip T. S. Lau

Philip T. S. Lau 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: 5888716
    Abstract: The invention provides a photographic element comprising a red light sensitive silver halide emulsion layer having associated therewith a cyan dye forming coupler having Formula (I) and a green light sensitive silver halide emulsion layer having associated therewith a magenta dye forming coupler having formula IIA or IIB: ##STR1## wherein the substituents are as defined herein.
    Type: Grant
    Filed: August 20, 1996
    Date of Patent: March 30, 1999
    Assignee: Eastman Kodak Company
    Inventors: James Lawrence Edwards, Philip T. S. Lau, Stanley Wray Cowan
  • Patent number: 5834166
    Abstract: The invention provides a photographic element which comprises a light-sensitive silver halide emulsion layer having associated therewith a cyan dye-forming coupler having the formula: ##STR1## wherein: each R.sub.1 independently represents an alkyl or aryl group;R.sub.2 represents a linear or branched alkyl group of 1 to 20 carbon atoms;R.sub.3 is selected from the group consisting of an alkyl group, an aryl group, a perfluoroalkyl group, or an arylamino group; andZ represents a hydrogen atom or a group capable of being split off by oxidized color developer.The element of the invention exhibits improved cyan dye light stability.
    Type: Grant
    Filed: October 31, 1996
    Date of Patent: November 10, 1998
    Assignee: Eastman Kodak Company
    Inventors: Philip T.S. Lau, Stanley W. Cowan, David Hoke
  • Patent number: 5726002
    Abstract: The invention provides a photographic element comprising a light sensitive silver halide emulsion layer having associated therewith a cyan coupler represented by formula (I) in combination with a phenolic solvent represented by formula (II): ##STR1## wherein: R.sub.3 represents an alkyl group of 2 to 15 carbon atoms;R.sub.4 and R.sub.5 each independently represents a hydrogen atom, an alkyl group or an aryl group;R.sub.6 represents an alkyl or aryl group;X represents a halogen atom; andZ represents a hydrogen atom or a group capable of being split off by oxidized color developer; andeach R independently represents a substituent while q represents an integer from 1 to 3;provided that all R groups taken together contain at least 8 carbon atoms.
    Type: Grant
    Filed: June 10, 1996
    Date of Patent: March 10, 1998
    Assignee: Eastman Kodak Company
    Inventors: Philip T. S. Lau, Stanley Wray Cowan
  • Patent number: 5686235
    Abstract: A photographic element comprises a light sensitive silver halide emulsion layer having associated therewith a cyan dye forming coupler having Formula (I): ##STR1## wherein R.sub.1 represents hydrogen or an alkyl group;R.sub.2 represents an alkyl group or an aryl group;n represents 1, 2, or 3;each X is located at a position of the phenyl ring meta or para to the sulfonyl group and is independently selected from the group consisting of alkyl, alkenyl, alkoxy, aryloxy, acyloxy, acylamino, sulfonyloxy, sulfamoylamino, sulfonamido, ureido, oxycarbonyl, oxycarbonylamino, and carbamoyl groups; andZ represents a hydrogen atom or a group which can be split off by the reaction of the coupler with an oxidized color developing agent.The element forms a dye upon development which has a desirably low wavelength of maximum absorbance and low unwanted green absorbance.
    Type: Grant
    Filed: August 20, 1996
    Date of Patent: November 11, 1997
    Assignee: Eastman Kodak Company
    Inventors: Philip T. S. Lau, Stanley Wray Cowan, Louis Joseph Rossi
  • Patent number: 5681689
    Abstract: The invention provides a photographic material comprising at least one light sensitive silver halide emulsion layer having associated therewith a yellow dye forming coupler having formula (I) or (II): ##STR1## wherein R represents an aromatic or heterocyclic group containing a group ionizable at pH 10 that is in conjugation with the double bond between the carbons to which A and X are respectively bonded through a .pi.-electron network;A is selected from the group consisting of hydrogen, a cyano group, an alkyl group, an aryl group, an alkylsulfonyl group, and an arylsulfonyl group;B is an alkyl group or an aryl group; andX represents hydrogen or a group capable of being split off upon coupling with oxidized color developer.
    Type: Grant
    Filed: May 10, 1996
    Date of Patent: October 28, 1997
    Assignee: Eastman Kodak Company
    Inventors: Philip T. S. Lau, Stanley Wray Cowan
  • Patent number: 5670302
    Abstract: A photographic element comprises a light sensitive silver halide emulsion layer having associated therewith a magenta coupler represented by formula (I): ##STR1## wherein: R.sub.1 represents a hydrogen atom or an alkyl group;R.sub.2 represents an alkyl group;Ar represents a phenyl or naphthyl group;X represents a substituent and "n" represents an integer of from 1 to 5; andZ represents a hydrogen atom or a group which can be split off by the reaction of the coupler with an oxidized color developing agent.The described naphtholic coupler provides a magenta dye image rather than the cyan dye image common to naphtholic couplers.
    Type: Grant
    Filed: June 16, 1996
    Date of Patent: September 23, 1997
    Assignee: Eastman Kodak Company
    Inventors: Philip T. S. Lau, Louis Joseph Rossi, Stanley Wray Cowan
  • Patent number: 5654132
    Abstract: A photographic element comprises a light-sensitive silver halide emulsion layer having associated therewith a cyan dye forming coupler having the formula: ##STR1## wherein: X represents hydrogen or a coupling-off group bonded to the coupling position of the coupler and capable of being split off by an oxidized color developer; andR represents an aliphatic or aromatic substituent group. The element provides improved hue of the cyan dye formed from the coupler upon coupling.
    Type: Grant
    Filed: May 10, 1996
    Date of Patent: August 5, 1997
    Assignee: Eastman Kodak Company
    Inventors: Philip T.S. Lau, Stanley Wray Cowan
  • Patent number: 5614357
    Abstract: The invention provides a photographic element comprising a light sensitive silver halide emulsion layer having associated therewith a cyan coupler represented by formula (I): ##STR1## wherein: R.sub.3 represents an alkyl group of 2 to 15 carbon atoms;R.sub.4 and R.sub.5 each independently represents a hydrogen atom, an alkyl group or an aryl group;R.sub.6 represents an alkyl or aryl group;X represents a halogen atom; andZ represents a hydrogen atom or a group capable of being split off by oxidized color developer.
    Type: Grant
    Filed: June 10, 1996
    Date of Patent: March 25, 1997
    Assignee: Eastman Kodak Company
    Inventors: Philip T. S. Lau, Stanley W. Cowan
  • Patent number: 5523199
    Abstract: A photographic element and imaging process employ a light-sensitive silver halide emulsion layer having associated therewith a magenta azine dye-forming coupler which is a phenol having(1) an acylamino group in the 2-position wherein the amino nitrogen contains a substituent which is an aliphatic or aromatic group;(2) hydrogen or a coupling-off group in the 4-position; and(3) a sulfonamido group in the 5-position.
    Type: Grant
    Filed: December 6, 1994
    Date of Patent: June 4, 1996
    Assignee: Eastman Kodak Company
    Inventors: Philip T. S. Lau, Rakesh Jain
  • Patent number: 5508148
    Abstract: A photographic element comprises a light sensitive silver halide emulsion layer having associated therewith a cyan dye-forming coupler dispersed in an organic solvent, the coupler having the formula: ##STR1## wherein A, B, and C are hydrogen or fluoride;X is selected from the group consisting of halogen, alkoxy and methyl groups;R is an aromatic or aliphatic group and n is 1 or 2;R' is a substituent group and m is from 0 to 4;COG is hydrogen or a coupling-off group capable of being split-off by an oxidized color developer; andwherein the substituent groups X, R, and R' are selected so as to ballast the coupler and keep it from wandering within the photographic elements.
    Type: Grant
    Filed: December 19, 1994
    Date of Patent: April 16, 1996
    Assignee: Eastman Kodak Company
    Inventors: Philip T. S. Lau, Thomas H. Jozefiak, Thomas R. Welter
  • Patent number: 5476757
    Abstract: A photographic element comprises a light sensitive silver halide emulsion layer having associated therewith a cyan dye-forming coupler dispersed in an organic solvent, the coupler having the formula: ##STR1## wherein A, B, and C are hydrogen or fluorine;X is selected from the group consisting of halogen, alkoxy and methyl groups;R is a straight chain aliphatic group which is unsubstituted or substituted with one or members selected from the group consisting of --F, --R", --OR", --SO.sub.2 R", --SO.sub.2 NHR", --CONHR", --COOR", --NHCOR", --NHSO.sub.2 R", and --OCOR" where R" is a primary or secondary alkyl group;R' is a substituent group and m is from 0 to 4;COG is hydrogen or a coupling-off group capable of being split-off by an oxidized color developer; andwherein the substituent groups X, R, and R' are selected so as to ballast the coupler and prevent it from wandering within the photographic coatings.
    Type: Grant
    Filed: December 19, 1994
    Date of Patent: December 19, 1995
    Assignee: Eastman Kodak Company
    Inventors: Philip T. S. Lau, Thomas H. Jozefiak, Thomas R. Welter
  • Patent number: 5457020
    Abstract: Novel bicyclic pyrazolo couplers containing a ballast group of formula (I): ##STR1## are useful in photographic materials and processes. The couplers exhibit increased coupling activity, and provide formation of dyes having improved maximum magenta image dye density, hue, and dye light stability when employed in color photographic materials and processes.
    Type: Grant
    Filed: December 18, 1992
    Date of Patent: October 10, 1995
    Assignee: Eastman Kodak Company
    Inventors: Philip T. S. Lau, Ping W. Tang, Stanley W. Cowan
  • Patent number: 5457008
    Abstract: The invention provides a photographic element comprising a light-sensitive photographic silver halide emulsion having associated therewith a coupler compound having the formula: ##STR1## wherein X represents a hydrogen atom or a coupling-off group;m is an integer from 0 to 4, n is 1 or 2, and p is an integer from 0 to 4; andA, B, and R each independently represent a substituent group.
    Type: Grant
    Filed: December 19, 1994
    Date of Patent: October 10, 1995
    Assignee: Eastman Kodak Company
    Inventors: Philip T. S. Lau, Thomas H. Jozefiak, Thomas R. Welter
  • Patent number: 5427898
    Abstract: Novel yellow dye-forming couplers, and photographic elements, emulsions and processes for developing images utilizing the novel couplers, are disclosed. The novel couplers include (a) an acyl acetanilide in which the acyl group has a monocyclic or multicyclic carbon center attached to the carbonyl moiety, and (b) an aryloxy coupling-off group at the coupling position of the acylacetanilide, the coupling-off group having in the ortho position a polarizable substituent.
    Type: Grant
    Filed: September 19, 1994
    Date of Patent: June 27, 1995
    Assignee: Eastman Kodak Company
    Inventors: Ping W. Tang, Philip T. S. Lau, Stanley W. Cowan, Terrence Mungal
  • Patent number: 5382502
    Abstract: 8-hydroxyquinoline and 5-hydroxyquinoline compounds of the following formulae: ##STR1## , wherein: R.sub.1 is a substituted or unsubstituted alkyl group with 8 to 30 carbon atoms;R.sub.2 is hydrogen or another substituent;X is a group capable of being released by a coupling reaction with an oxidized aromatic primary amine developing agent; andZ is a nonnucleophilic substituent or a group not capable of being eliminated during or following a coupling reaction with an oxidized color developerhave been found to be useful in photographic materials as cyan dye-forming couplers. A process in which a substituted aminophenol salt reacts with two molar equivalents of an enolizable aldehyde containing at least two a-substituted hydrogen atoms is used to make these couplers and other hydroxyquinoline compounds.
    Type: Grant
    Filed: July 23, 1993
    Date of Patent: January 17, 1995
    Assignee: Eastman Kodak Company
    Inventors: Philip T. S. Lau, Danny R. Thompson, Stanley W. Cowan
  • Patent number: 5360713
    Abstract: Yellow dye-forming couplers of the acylacetanilide class, having an electron withdrawing group or electronegative element attached to the keto functional group, have excellent light-absorption characteristics and are useful in photographic elements.
    Type: Grant
    Filed: November 12, 1992
    Date of Patent: November 1, 1994
    Assignee: Eastman Kodak Company
    Inventors: Ping W. Tang, Philip T. S. Lau, Stanley W. Cowan
  • Patent number: 5358838
    Abstract: The invention provides new yellow-dye-forming couplers, new yellow dyes formed therefrom, and new photographic elements containing the new couplers. The new couplers have the structure (I): ##STR1## wherein ##STR2## has the structure (II) ##STR3## wherein each --R-- is independently a substituted or unsubstituted alkylene, alkoxylene, arylene, or aryloxylene group, and Q-- has the structure (III): ##STR4## wherein: each R.sup.1 -- is independently t-butyl or a substituted aryl group;each Z-- is independently H--, halo, or a substituted or unsubstituted alkyl, aryl, alkoxy, or aryloxy group;each M-- is independently H-- or a substituent; and each R.sup.2 -- is independently H-- or a substituent.
    Type: Grant
    Filed: December 17, 1993
    Date of Patent: October 25, 1994
    Assignee: Eastman Kodak Company
    Inventors: Ping-Wah Tang, Philip T. S. Lau, Stanley W. Cowan
  • Patent number: 5358835
    Abstract: The invention provides new yellow-dye-forming couplers, new yellow dyes formed therefrom, and new photographic elements containing the new couplers. The new couplers have the structure (I): ##STR1## wherein ##STR2## has the structure (II) ##STR3## wherein each --R-- is independently a substituted or unsubstituted alkylene, alkoxylene, arylene, or aryloxylene group, and Q-- has the structure (III): ##STR4## wherein: each R.sup.1 -- is independently t-butyl or a substituted aryl group;each Z-- is independently H--, halo, or a substituted or unsubstituted alkyl, aryl, alkoxy, or aryloxy group; andeach X-- is independently H-- or a coupling-off group.
    Type: Grant
    Filed: December 17, 1993
    Date of Patent: October 25, 1994
    Assignee: Eastman Kodak Company
    Inventors: Ping-Wah Tang, Philip T. S. Lau, Stanley W. Cowan
  • Patent number: 5358836
    Abstract: The invention provides new magenta-dye-forming couplers, new magenta dyes formed therefrom, and new photographic elements containing the new couplers. The new couplers have the structure (I): ##STR1## wherein ##STR2## has the structure (II) ##STR3## wherein each --R-- is independently a substituted or unsubstituted alkylene, alkoxylene, arylene, or aryloxylene group, andeach --L-- is independently a substituted or unsubstituted alkylene, alkoxylene, arylene, aryloxylene, or aryloxyalkylene group, and Q-- has the structure (III): ##STR4## wherein: each R.sup.1 -- is independently H-- or a substituent; each X-- is independently H-- or a coupling-off group; andeach of D, E, and Z is independently a substituted or unsubstituted methine group, .dbd.
    Type: Grant
    Filed: December 17, 1993
    Date of Patent: October 25, 1994
    Assignee: Eastman Kodak Company
    Inventors: Ping-Wah Tang, Philip T. S. Lau, Stanley W. Cowan
  • Patent number: 5358837
    Abstract: The invention provides new magenta-dye-forming couplers, new magenta dyes formed therefrom, and new photographic elements containing the new couplers. The new couplers have the structure (I):Q--G--Q.sub.(I)wherein --G-- has the structure (II):--L--NH--SO.sub.2 --R--SO.sub.2 -NH--L--.sub.(II)wherein --R-- is substituted or unsubstituted alkylene, alkoxylene, arylene, or aryloxylene, andeach --L-- is independently substituted or unsubstituted alkylene, alkoxylene, arylene, aryloxylene, or aryloxyalkylene, andQ-- has the structure (III ): ##STR1## wherein: each R.sup.1 -- is independently H-- or a substituent; each X-- is independently H-- or a coupling-off group; andeach of D, E, and Z is independently a substituted or unsubstituted methine group, .dbd.
    Type: Grant
    Filed: December 17, 1993
    Date of Patent: October 25, 1994
    Assignee: Eastman Kodak Company
    Inventors: Ping-Wah Tang, Terrence C. Mungal, Philip T. S. Lau, Stanley W. Cowan