Patents by Inventor Constantine C. Petropoulos

Constantine C. Petropoulos 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).

  • Modified polyester useful as photographic roll film support
    Patent number: 5138024
    Abstract: A copolyester is synthesized by reacting a dialkyl ester of an aromatic dicarboxylic acid (e.g., dimethyl terephthalate) with ethylene glycol, low molecular weight poly(ethylene glycol) and a salt of a sulfonic acid-substituted aromatic dicarboxylate (e.g., sodium sulfoisophthalic acid) simultaneously in a first stage reaction in the presence of a phosphite or phosphate stabilizer. The intermediate product of the first stage is further reacted in a second stage in the presence of a polycondensation catalyst to obtain a random copolyester of the desired molecular weight. The copolyester is extruded to form a film which, after orientation and heat setting, has excellent clarity and is useful as a photographic film support. Aqueous processing of the film relaxes any core set or curl.
    Type: Grant
    Filed: January 25, 1991
    Date of Patent: August 11, 1992
    Assignee: Eastman Kodak Company
    Inventors: Carl T. Brozek, Robert C. Daly, Robert H. Fehnel, Constantine C. Petropoulos
  • Negative-working polymers useful as electron beam resists
    Patent number: 4289842
    Abstract: Novel acrylate copolymer materials function as electron-beam resists with enhanced sensitivity and enhanced plasma etch resistance. The method of using such materials as an electron-beam resist is also described.
    Type: Grant
    Filed: June 27, 1980
    Date of Patent: September 15, 1981
    Assignee: Eastman Kodak Company
    Inventors: Zoilo C. H. Tan, Constantine C. Petropoulos, Frederick J. Rauner
  • Novel radiation sensitive compounds and radiation sensitive compositions containing the same
    Patent number: 4233443
    Abstract: Pyrylium, thiapyrylium and selenapyrylium salts and derivatives thereof having a trimethine linkage containing an aryl substituent attached to at least one carbon atom of the trimethine linkage are disclosed. Radiation sensitive compositions, e.g., photoconductive compositions, containing such materials are also disclosed.
    Type: Grant
    Filed: March 26, 1979
    Date of Patent: November 11, 1980
    Assignee: Eastman Kodak Company
    Inventors: Constantine C. Petropoulos, George A. Reynolds, James A. VanAllan
  • Radiation sensitive compositions containing pyrylium compounds
    Patent number: 4173473
    Abstract: Pyrylium, thiapyrylium and selenapyrylium salts and derivatives thereof having a trimethine linkage containing an aryl substituent attached to at least one carbon atom of the trimethine linkage are disclosed. Radiation sensitive compositions, e.g., photoconductive compositions, containing such materials are also disclosed.
    Type: Grant
    Filed: July 6, 1977
    Date of Patent: November 6, 1979
    Assignee: Eastman Kodak Company
    Inventors: Constantine C. Petropoulos, George A. Reynolds, James A. Van Allan
  • Radiation sensitive polymeric o-nitrophenyl acetals and element
    Patent number: 4131465
    Abstract: Radiation-sensitive linear polymers comprise repeating structural units containing an o-nitrophenyl acetal. The polymer is formed, for example, by the linear polycondensation of o-nitrobenzaldehyde with a particular dihydroxy alcohol. The polymers are useful as coatings to form positive-working radiation-sensitive elements such as photoresists or lithographic printing plates.
    Type: Grant
    Filed: September 27, 1977
    Date of Patent: December 26, 1978
    Assignee: Eastman Kodak Company
    Inventor: Constantine C. Petropoulos