Patents by Inventor George H. Nawn

George H. Nawn 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: 4593108
    Abstract: There are disclosed novel compounds which are represented by the formula ##STR1## wherein X represents the nonmetallic atoms necessary to form a nucleus which completes a 5- or 6-membered heterocyclic moiety, R is H, an alkali metal or a group which is cleavable in aqueous alkaline medium and Z is H, alkyl having from 1 to 10 carbon atoms, aralkyl such as benzyl or phenethyl, phenyl or substituted phenyl. The compounds are useful in photographic applications.
    Type: Grant
    Filed: June 11, 1982
    Date of Patent: June 3, 1986
    Assignee: Polaroid Corporation
    Inventors: Avinash C. Mehta, George H. Nawn, Lloyd D. Taylor
  • Patent number: 4390613
    Abstract: There is disclosed a diffusion transfer photographic system wherein development of an exposed photosensitive element with an aqueous alkaline processing composition is effected in the presence of a compound represented by the formula ##STR1## wherein X represents the nonmetallic atoms necessary to form a nucleus which completes a 5- or 6-membered heterocyclic moiety on said structure including substituted rings and fused rings; R is H, an alkali metal or a group which is cleavable in a photographic aqueous alkaline processing composition; and R.sub.1 is either a group which has a pKa of from about 7 to about 14 which is ionizable to an anion whereby the silver salt of the mercaptan (resulting from cleavage or ionization of --SR) is rendered more soluble in the pH range within which R.sub.1 is ionized to an anion than it is below that pH range, or a precursor of such a group.
    Type: Grant
    Filed: January 5, 1981
    Date of Patent: June 28, 1983
    Assignee: Polaroid Corporation
    Inventors: Avinash C. Mehta, George H. Nawn, Lloyd D. Taylor
  • Patent number: 4355101
    Abstract: Novel compounds which are represented by the formula ##STR1## wherein X represents the nonmetallic atoms necessary to form a nucleus which completes a 5- or 6-membered heterocyclic moiety, R is a group which is cleavable in aqueous alkaline medium and R.sub.1 is either a group which has a pKa of from about 7 to about 14 which is ionizable to an anion and wherein the silver salt of the mercaptan resulting from cleavage of -SR is rendered more soluble in the pH range within which R.sub.1 is ionized to an anion than it is below that pH range or a precursor of such a group. The compounds are useful in photographic applications.
    Type: Grant
    Filed: January 5, 1981
    Date of Patent: October 19, 1982
    Assignee: Polaroid Corporation
    Inventors: Avinash C. Mehta, George H. Nawn, Lloyd D. Taylor
  • Patent number: 4355092
    Abstract: There are disclosed novel compounds which are represented by the formula ##STR1## wherein X represents the nonmetallic atoms necessary to form a nucleus which completes a 5- or 6-membered heterocyclic moiety, R is H, an alkali metal or a group which is cleavable in aqueous alkaline medium and Z is H, alkyl having from 1 to 10 carbon atoms, aralkyl such as benzyl or phenethyl, phenyl or substituted phenyl. The compounds are useful in photographic applications.
    Type: Grant
    Filed: January 5, 1981
    Date of Patent: October 19, 1982
    Assignee: Polaroid Corporation
    Inventors: Avinash C. Mehta, George H. Nawn, Lloyd D. Taylor
  • Patent number: 4255512
    Abstract: A multicolor diffusion transfer photographic system wherein development of an exposed multilayer photsensitive element is effected in the presence of a ligand which is represented by the formula ##STR1## wherein R is hydrogen, alkyl or hydroxyalkyl, m is an integer of from 3 to 10 and n is 0 or an integer of from 1 to 3 with the proviso that the sum of m and n is not greater than 10.
    Type: Grant
    Filed: December 26, 1979
    Date of Patent: March 10, 1981
    Assignee: Polaroid Corporation
    Inventors: George H. Nawn, Donald O. Rickter
  • Patent number: 4248955
    Abstract: A multicolor diffusion transfer photographic system wherein development of an exposed multilayer photosensitive element is effected in the presence of an oligomer which is represented by the formulaR.sub.1 O(CH.sub.2 CH.sub.2 O).sub.m R.sub.2wherein R.sub.1 and R.sub.2 each independently may be --CH.sub.3 or --C.sub.2 H.sub.5 and m is an integer of from 4 to 10.
    Type: Grant
    Filed: December 26, 1979
    Date of Patent: February 3, 1981
    Assignee: Polaroid Corporation
    Inventor: George H. Nawn