Patents Represented by Attorney P. S. Kalyanaraman
  • Patent number: 5170461
    Abstract: This invention provides superior electrooptic devices containing an organic polymeric waveguiding medium, and a process of fabricating such devices. The fabrication process utilizes a substantially stress-free organic polymeric substrate on top of which the necessary organic layers are successively deposited. The substrate is so selected that its thermal expansion coefficient is substantially close to that of the cladding layers and of the waveguiding layer.
    Type: Grant
    Filed: December 11, 1991
    Date of Patent: December 8, 1992
    Assignee: Hoechst Celanese Corp.
    Inventors: Hyun N. Yoon, Frank J. Onorato, John P. Riggs
  • Patent number: 5155195
    Abstract: In one embodiment this invention provides a novel type of copolymer which can be formed into a thin film nonlinear optical medium which exhibits superior light transmission properties, and which has excellent adhesion properties when laminated with inorganic or organic layers.
    Type: Grant
    Filed: May 16, 1991
    Date of Patent: October 13, 1992
    Assignee: Hoechst Celanese Corp.
    Inventor: Bernice I. Feuer
  • Patent number: 5145928
    Abstract: This invention provides novel polymers that contain, in their side chains, 4-benzoyloxyphenyl moieties. These polymers have utility as coatings to protect polyester materials from damage due to ultraviolet radiation.
    Type: Grant
    Filed: January 28, 1991
    Date of Patent: September 8, 1992
    Assignee: Hoechst Celanese Corp.
    Inventors: Gunilla E. Gillberg-LaForce, Josefina L. Pruksarnukul
  • Patent number: 5143947
    Abstract: Radiation curable compositions useful as coatings for wood, metal, glass, fabric, paper, fiber and plastics are made from copolymers of 4-hydroxystyrene and an alkadiene or an allyl ester of an ethylenically unsaturated acid blended wit ethylenically unsaturated compounds.
    Type: Grant
    Filed: November 13, 1989
    Date of Patent: September 1, 1992
    Assignee: Hoechst Celanese Corporation
    Inventor: Balaram Gupta
  • Patent number: 5139837
    Abstract: Provided is an optical information medium comprised of an organic information layer and a resinous continuous film overcoat layer which is coated over said organic information layer. The resinous overcoat layer is no thicker than, and most preferably thinner than said information layer, and is of a thickness of about 100 angstroms or less. It is most preferred that the overcoat layer is comprised of a water soluble polymer. The resulting optical information medium advantageously exhibits an extremely sharp threshold for marking, as well as improved carrier to noise ratio.
    Type: Grant
    Filed: March 8, 1990
    Date of Patent: August 18, 1992
    Assignee: Hoechst Celanese Corp.
    Inventors: Palaiyur S. Kalyanaraman, Harris A. Goldberg, Frank J. Onorato
  • Patent number: 5134605
    Abstract: Provided is a method for reading information recorded in an information layer comprised of a fluorescent dye. In order to read the recorded information, the tip of a scanning tunneling microscope is passed over the information layer, said scanning tunneling microscope being of sufficient voltage to excite the fluorescent dye material to an excited state. Upon return of the dye material to ground state, fluorescence results. By measuring the fluorescence, or absence thereof, the recorded information can be deciphered.
    Type: Grant
    Filed: August 20, 1991
    Date of Patent: July 28, 1992
    Assignee: Hoechst Celanese Corp.
    Inventors: Harris A. Goldberg, Ronald G. Reifenberger
  • Patent number: 5131068
    Abstract: In one embodiment this invention provides a frequency doubling optical waveguide consisting of a substrate-supported polymeric thin film which exhibits second order nonlinear optical response and is thickness variation insensitive, and which has a periodic structure for quasi-phase matching of propagating laser wave radiation. In a preferred embodiment the waveguide has a two-dimensional channel structure for intensified single mode wave transmission.
    Type: Grant
    Filed: October 23, 1990
    Date of Patent: July 14, 1992
    Assignee: Hoechst Celanese Corp.
    Inventors: Garo Kanarian, Robert Norwood
  • Patent number: 5128223
    Abstract: In one embodiment this invention provides a process for preparing a holographic composition which is a thin film of polyphenyl acylate polymer which has a photo-Fries molecular rearrangement corresponding to a recorded refractive index pattern induced by exposure to a coherent light interference pattern.
    Type: Grant
    Filed: June 15, 1990
    Date of Patent: July 7, 1992
    Assignee: Hoechst Celanese Corp.
    Inventors: Gunilla E. Gillberg-LaForce, Edward Yokley, James E. Kuder, Elizabeth Fernekess
  • Patent number: 5121376
    Abstract: An apparatus and a process for storing and retrieving information comprising an optical disk having a substrate and a recording layer of a predetermined optical thickness disposed on the substrate. The indices of refraction of the substrate and recording layer are unequal, causing Fresnel reflections from the surface of the layer and the boundary between the substrate and the layer. The optical thickness of the layer is selectively changeable to a plurality of distinct values different from the predetermined value, thereby changing the intensity reflectance of the optical disk to one of a plurality of values. Differences in the intensity of light reflected or transmitted by the disk are detected and serve to represent information according to a multi-level rather than binary digital system.
    Type: Grant
    Filed: January 4, 1990
    Date of Patent: June 9, 1992
    Assignee: Hoechst Celanese Corp.
    Inventors: James E. Kuder, Harris A. Goldberg
  • Patent number: 5120793
    Abstract: Ether derivatives of polymers of p-hydroxystyrene are made by reacting the polymer through Michael addition with an ethylenically unsaturated compound which contains an electron withdrawing group on the carbon atom alpha to the unsaturation.
    Type: Grant
    Filed: April 18, 1990
    Date of Patent: June 9, 1992
    Assignee: Hoechst Celanese Corp.
    Inventor: Balaram Gupta
  • Patent number: 5106211
    Abstract: This invention provides polymeric chanel waveguides which are formed by means of an excimer laser photoablation procedure. The smooth-wall channel waveguides polymeric medium is in combination with polymeric cladding layers to form a laminated matrix. The polymers in the waveguiding medium and the cladding layers of the laminated matrix have side chains which exhibit second order nonlinear optical susceptibility, and which can be molecularly oriented by an electric field.
    Type: Grant
    Filed: February 14, 1991
    Date of Patent: April 21, 1992
    Assignee: Hoechst Celanese Corp.
    Inventors: Kophu Chiang, David Haas
  • Patent number: 5102739
    Abstract: Provided is a method for preparing an optical information medium which comprises a polycarbonate substrate. A polycarbonate substrate is subjected to an aqueous ammonia solution treatment at a temperature below ambient temperatures and for an extended period of time. This treatment occurs prior to assembly of the optical information medium. Use of the treated polycarbonate substrate in the optical information medium results in the medium exhibiting a high level of performance over an extended useful life.
    Type: Grant
    Filed: March 1, 1990
    Date of Patent: April 7, 1992
    Assignee: Hoechst Celanese Corp.
    Inventors: Frank J. Onorato, David E. Nikles, Leroy McKenzie, Jeffrey A. Schneider
  • Patent number: 5096742
    Abstract: Provided is a method for stabilizing an optical recording medium containing a polycarbonate substrate. The method comprises treating the substrate material in a high temperature, high humidity environment for an extended period of time. Dramatic improvements in the useful life of the optical recording medium in which the treated polycarbonate substrate is used have been found to result.
    Type: Grant
    Filed: January 9, 1990
    Date of Patent: March 17, 1992
    Assignee: Hoechst Celanese Corporation
    Inventors: David E. Nikles, Charles E. Forbes
  • Patent number: 5087390
    Abstract: In one embodiment this invention provides a tetraazaporphyrin dye mixture which exhibits light absorption over a spectrum range of about 660-850 nm, and provides a process for production of the dye mixture.An invention dye mixture has utility in optical recording media, or as a nonlinear optical component in optical light switch or light modulator devices.Illustrative of an invention dye mixture is a blend of dye constituents respectively having varying combinations of phthalocyanine and naphthalocyanine entities in the macrocyclic structures.
    Type: Grant
    Filed: April 4, 1989
    Date of Patent: February 11, 1992
    Assignee: Hoechst Celanese Corp.
    Inventors: James R. Sounik, Jacquelyn Popolo
  • Patent number: 5059510
    Abstract: Provided is an information recording medium, e.g., an optical recording medium, and a method for recording information thereon. The information layer of the recording medium comprises an organo macrocyclic chromophore containing a central hetero atom or two central hydrogen atoms or isotopes of hydrogen, e.g., a naphthalocyanine having silicon as the hetero atom, which chromophore is substituted with at least one substituent conferring film forming properties to the chromophore, e.g., a monomer or oligomeric substituent comprised of acid, amide or ester units. The information layer thereby offers excellent thermomechanical properties and exhibits excellent absorption properties all in a single component material. By utilizing a single component material, the problem of dye/polymer phase separation frequently encountered in dye/polymer mixtures is also overcome.
    Type: Grant
    Filed: August 22, 1989
    Date of Patent: October 22, 1991
    Assignee: Hoechst Celanese Corp.
    Inventors: R. Sidney Jones, Jr., David E. Nikles, Malcolm E. Kenney
  • Patent number: 5057588
    Abstract: In one embodiment this invention provides vinylidene copolymers with alternating monomeric units as illustrated by the following structure: ##STR1## An invention vinylidene copolymer in the form of an electret film exhibits a high level of longitudinal piezoelectric effect, and has excellent processability and thermal stability properties.
    Type: Grant
    Filed: March 9, 1990
    Date of Patent: October 15, 1991
    Assignee: Hoechst Celanese Corp.
    Inventors: Anthony J. East, Anthony B. Conciatori
  • Patent number: 5053323
    Abstract: Provided is an optical information medium containing an information layer comprised of a 1-phenyl substituted naphthalocyanine. Also provided is a method for easily synthesizing the naphthalocyanine chromophore used in the information layer. The use of such naphthalocyanine chromophores in the information layer of an optical information medium provides one with many advantages. In the manufacture of the medium, these advantages arise due to the increased solubility exhibited by the chromophore in conventional organic solvents. As well, the chromophores exhibit excellent and unique optical properties useful in the recording of optical information.
    Type: Grant
    Filed: February 27, 1990
    Date of Patent: October 1, 1991
    Inventors: James P. Shepherd, Palaiyur S. Kalyanaraman
  • Patent number: 5051977
    Abstract: Provided is a method of reading information contained in an information medium by utilizing a scanning, tunneling microscope in conjunction with a substrate layer which fluoresces when high energy electrons pass into contact therewith. The method comprises providing an information medium comprised of an information layer which contains a track of information bits and the fluorescing substrate layer. A tip of a scanning tunneling microscope is then passed over the information layer, with the resulting fluorescence being measured. By utilizing the unique resolution available from the scanning tunneling microscope and the fluorescence of the substrate layer in order to read the information recorded, a surprisingly accurate and efficient method is achieved for reading highly densified information.
    Type: Grant
    Filed: August 30, 1989
    Date of Patent: September 24, 1991
    Assignee: Hoechst Celanese Corp.
    Inventor: Harris A. Goldberg
  • Patent number: 5039798
    Abstract: Provided are novel naphthalocyanine dimer compounds of the general formula:RO--YNc--O--NcY--OR (I)wherein Nc represents a naphthalocyanine moiety, which can be substituted or unsubstituted; Y represents a central hetero atom of the naphthalocyanine moiety; and, OR represents an alkoxide cap bonded to the central hetero atom Y, with the first carbon atom of the alkoxide (OR) capping group being a tertiary carbon. Also provided is a method for preparing the dimer compounds, which method comprises reacting a naphthalocyanine dihalide in solution with a tertiary alcohol and a nucleophile. The process efficiently and reproducibly provides a naphthalocyanine oxo-bridged dimer having terminal alkoxide caps.
    Type: Grant
    Filed: March 1, 1990
    Date of Patent: August 13, 1991
    Assignee: Hoechst Celanese Corp.
    Inventor: Robert E. Johnson
  • Patent number: 5023168
    Abstract: Provided is a method for preparing polysiloxy containing naphthalocyanine compounds. The method comprises reacting a cyclosiloxane with a nucleophile to open the ring of the cyclosiloxane. The ring opened cyclosiloxane is then reacted with a naphthalocyanine precursor and a capping group compound. The nucleophile can perform the dual role of the nucleophile and the capping group compound. The method permits the preparation of siloxane containing naphthalocyanine compounds in a more proficient manner through the use of cyclosiloxanes as reactants.
    Type: Grant
    Filed: March 1, 1990
    Date of Patent: June 11, 1991
    Assignee: Hoechst Celanese Corp.
    Inventor: Robert E. Johnson