Patents Represented by Attorney Palaiyur S. Kalyanaraman
  • Patent number: 5753145
    Abstract: This invention provides novel liquid crystalline polymers which, when blended with a suitable dye at a suitable high temperature and extruded, yields polarizer films with superior thermal and hygroscopic stability and polarizing efficiency. The invention further provides a process to prepare such polarizer films.
    Type: Grant
    Filed: June 2, 1995
    Date of Patent: May 19, 1998
    Assignee: Hoecst Celanese Corp.
    Inventors: Chia-Chi Teng, Hyun Nam Yoon, Mohammad Mortazavi
  • Patent number: 5746949
    Abstract: This invention provides novel liquid crystalline polymers which comprise, in the repeat units of their main chains, residues of suitable dichroic dyes. The polymers yield polarizer films with superior polarizing efficiency, transmittance, dichroic ratio, and thermal and humidity stability. The invention further discloses suitable processes to prepare such polymers and polarizer films therefrom.
    Type: Grant
    Filed: November 21, 1995
    Date of Patent: May 5, 1998
    Assignee: Hoechst Celanese Corp.
    Inventors: Sunny S. Shen, David W. Polis, Hyun N. Yoon, Tze-Pei Tien
  • Patent number: 5739383
    Abstract: Described herein is a novel process to resolve a racemic compound into its optically active isomers without need for chemical transformation such as salt formation. The process advantageously utilizes polymers containing chiral moieties in their repeat units as well as exhibiting critical solution temperature behavior in a suitable solvent. An embodiment describes the resolution of tryptophan.
    Type: Grant
    Filed: November 26, 1996
    Date of Patent: April 14, 1998
    Assignee: Hoechst Celanese Corp.
    Inventors: Hyun-Nam Yoon, Mengshi Lu, Naoya Ogata
  • Patent number: 5738918
    Abstract: This invention provides laminates useful for display device applications. An illustrative laminate comprises a polarizing film, and a protective layer, bonded by means of an intermediary adhesive layer. A polarizing film useful for such a laminate construction comprises a liquid crystalline polyester and a dichroic dye. The invention further provides a process to prepare such laminates.
    Type: Grant
    Filed: June 14, 1996
    Date of Patent: April 14, 1998
    Assignee: Hoechst Celanese Corp
    Inventors: Sunny S. Shen, Hyun Nam Yoon, Chia-Chi Teng
  • Patent number: 5707566
    Abstract: This invention provides a novel process to prepare high performance polarizing film. In one embodiment, the process includes melt-blending a film-forming wholly aromatic thermotropic liquid crystalline polyester and a dichroic dye and then extruding the blend at a suitable temperature to yield polarizer films with superior polarizing efficiency and thermal and humidity stability.
    Type: Grant
    Filed: June 2, 1995
    Date of Patent: January 13, 1998
    Assignee: Hoechst Celanese Corp.
    Inventors: Sunny S. Shen, Tze-Pei Tien, Hyun Nam Yoon
  • Patent number: 5695710
    Abstract: A process for making a transparent blow molded product made of a copolyester of PET and PEN that does not thermally deform at temperatures up to 85-87 C., and the product of that process, especially a transparent blow molded bottle. The copolyester is made by transesterifying a 20/80 (w/w) PEN/PET via melt extrusion at a temperature of from about 250 C. to about 290 C. for a time sufficient to produce about 1-20% transesterification of said polymers, forming a copolymer. The copolyester is then injection molded at a temperature of from 290 C. to about 320 C. to form a transparent preform in which the copolymer has a glass transition temperature of about 85 C. or higher and a melting point temperature of at least about 225 C. The copolymer is then thermo-stretch blow molded to form a transparent product.
    Type: Grant
    Filed: May 9, 1995
    Date of Patent: December 9, 1997
    Assignee: Hoechst Celanese Corp.
    Inventors: Paul N. Chen, Sr., Kenith P. Music, Gerald W. McNeely
  • Patent number: 5672296
    Abstract: This invention provides novel liquid crystalline polymers which, when mixed with a suitable dye and extruded, yields polarizer films with superior polarizing efficiency, transmittance, dichroic ratio, and thermal and humidity stability. The invention further provides a process to prepare such polymers and polarizer films therefrom.
    Type: Grant
    Filed: June 2, 1995
    Date of Patent: September 30, 1997
    Assignee: Hoechst Celanese Corp.
    Inventors: Sunny S. Shen, Hyun Nam Yoon, Mohammad Mortazavi
  • Patent number: 5672725
    Abstract: The invention provides a novel process to oxidize 1,4-dihydroxy aromatic compounds into the corresponding quinones using sulfuryl chloride as the oxidant. The process is simple and cost effective and provides an efficient way to synthesize hindered quinones.
    Type: Grant
    Filed: September 21, 1995
    Date of Patent: September 30, 1997
    Assignee: Hoechst Celanese Corp.
    Inventor: David W. Polis
  • Patent number: 5656714
    Abstract: An aromatic polyester having recurring monomer units derived from terephthalic acid, 6-hydroxy-2-naphthoic acid, p-hydroxybenzoic acid, 4,4'-biphenol, and resorcinol. This polyester is melt processible and may be amorphous or semi-crystalline.
    Type: Grant
    Filed: June 2, 1995
    Date of Patent: August 12, 1997
    Assignee: Hoechst Celanese Corp.
    Inventors: Sunny S. Shen, Larry F. Charbonneau
  • Patent number: 5609945
    Abstract: An image-bearing element comprising of a white, translucent, metallized film article wherein the film article comprises a flexible, heat resistant, polymeric film material with opposite sides. The film material has deposited on a first side a metal coating which both reflects and transmits visible light and capable of transmitting from about 1% to about 70% of incident visible light cast thereon. The second side of the film material has a white outermost surface and has a visible light opacity of from about 0.5 to about 0.98.
    Type: Grant
    Filed: September 29, 1995
    Date of Patent: March 11, 1997
    Assignee: Bayer Corporation
    Inventors: Robert J. von Trebra, Gerald A. Smith, Roy E. Hensel, Oliver A. Barton, deceased
  • Patent number: 5545506
    Abstract: This invention relates to negative working color proofing sheet constructions which, upon exposure to an actinic radiation source through a screened image, can accurately reproduce said image. The construction is useful as a color proofing film which can be employed to accurately predict the image quality from a lithographic printing process. The image is produced by forming a composite of a receiver sheet, an adhesive layer, a color layer and cover sheet. Upon imagewise exposure, a negative image appears on the receiver base after dry peel apart development.
    Type: Grant
    Filed: June 24, 1992
    Date of Patent: August 13, 1996
    Assignee: Hoechst Celanese Corporation
    Inventors: Wojciech A. Wilczak, Stephan J. W. Platzer, David L. Siegfried
  • Patent number: 5541249
    Abstract: Provided is an injection moldable composition suitable for forming ceramic or metallic greenbodies. The composition comprises in combination an inorganic or metallic filler in an amount of from about 63 volume percent to about 92 volume percent, a binding organic matrix resin, and an organosilane processing reagent represented by the general formula:SiX.sub.1 X.sub.2 X.sub.3 X.sub.4wherein at least one of X.sub.1, X.sub.2, X.sub.3 or X.sub.4 is an unfunctionalized alkyl or alkenyl group having 10 to 35 carbon atoms and at least one of X.sub.1, X.sub.2, X.sub.3 or X.sub.4 is an alkoxy group or halide, such that the moldable composition exhibits a low initial mixing torque upon mechanical agitation. These compositions offer excellent advantage in processibility using conventional mixing and molding equipment.Also provided is a process for preparing the moldable compositions.
    Type: Grant
    Filed: December 18, 1990
    Date of Patent: July 30, 1996
    Assignee: Hoechst Celanese Corp.
    Inventors: O. Richard Hughes, Hongkyu Kim, Gerd Wingefeld
  • Patent number: 5436106
    Abstract: The invention relates to a positive-working colored photosensitive recording material for the production of a color test image, composed of a temporary layer carrier, a photosensitive layer containing dyestuff or pigment, binder and quinonediazide compound and an adhesive layer which can be activated by means of heat, wherein a release layer based on polyvinyl alcohol is present on the surface of the temporary layer carrier, the photosensitive layer comprises, as the quinonediazide compound, an esterification product of a compound containing one or more phenolic hydroxyl groups and o-quinonediazide-sulfonyl chloride, and, as the binder, a novolak-free phenolic polymer resin and/or a reaction product of the phenolic polymer resin with a monoisocyanate, and the adhesive layer comprises a alkali-insoluble organic polymer and an alkali-soluble polyester. The invention also relates to a process for the production of a color test image using the recording material described.
    Type: Grant
    Filed: July 11, 1994
    Date of Patent: July 25, 1995
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Dieter Mohr, Martin Benzing, Juergen Mertes, Guenter Hultzsch, Ine Gramm, Manfred Michel, Andreas Elsaesser, Shane Hsieh, David L. Siegfried
  • Patent number: 5436112
    Abstract: This invention provides novel ethylenically unsaturated urethane monomers and photoreactive compositions comprising such monomers as essential constituents. The monomers can be photopolymerized or photocrosslinked and are useful in coating systems and multilayer color proofing systems. Additionally, they offer superior advantages such as significantly reduced migration between layers in multilayer color proofing systems.
    Type: Grant
    Filed: April 1, 1994
    Date of Patent: July 25, 1995
    Assignee: Hoechst Celanese Corporation
    Inventors: Shane Hsieh, Wojciech A. Wilczak
  • Patent number: 5432046
    Abstract: Provided herein is a brushgraining process to improve the quality of lithographic printing plate substrate surfaces. In the process, the surface is brushed in an aqueous slurry comprising a mixture of particulates of alumina and quartz in a weight ratio range 95:5 to 5:95, with the particulates being in the size range of 1-20 microns. Such a process surprisingly lessens the number of scratches produced on the substrate surface than when compared to using alumina alone or quartz alone or a mixture of alumina and quartz with particle sizes higher than the range disclosed.
    Type: Grant
    Filed: September 29, 1993
    Date of Patent: July 11, 1995
    Assignee: Hoechst Celanese Corporation
    Inventors: Stanley F. Wanat, Major S. Dhillon, Gerhard Sprintschnik, Allen W. Loveland, Dennis A. King
  • Patent number: 5429903
    Abstract: This invention relates to water developable, negative working photosensitized sheet constructions which, upon exposure to an actinic radiation source through a screened image, can accurately reproduce said image. The construction is useful as a color proofing film which can be employed to predict the image quality from a lithographic printing process. The invention provides both overlay and transfer type proofing sheets which have good fingerprint resistance.
    Type: Grant
    Filed: June 17, 1994
    Date of Patent: July 4, 1995
    Assignee: Hoechst Celanese Corporation
    Inventor: Stanley F. Wanat
  • Patent number: 5399456
    Abstract: A process for converting a normally positive working photosensitive composition to a negative working composition. One forms a composition containing an alkali soluble resin, a 1,2 quinone diazide-4-sulfonyl compound and an acid catalyzed crosslinker in a solvent mixture. After drying and imagewise exposing, the composition is baked and developed to produce a negative image.
    Type: Grant
    Filed: November 19, 1992
    Date of Patent: March 21, 1995
    Assignee: Hoechst Celanese Corporation
    Inventors: Mark A. Spak, Donald Mammato, Dana Durham, Sangya Jain
  • Patent number: 5380867
    Abstract: A process is provided whereby S(+)-ibuprofen or R(-)-ibuprofen L-lysinate salt is produced by selective precipitation from a mixture containing enantiomers of ibuprofen and L-lysine. The quantity of L-lysine is not more than about a molar equivalent of the quantity of one of the enantiomers in the ibuprofen enantiomeric mixture. Upon precipitation of one ibuprofen enantiomer from the mixture, the overall precipitate and reaction mixture can be held for a sufficient period of time at a second temperature to allow the first precipitate to redissolve into the reaction mixture and the other ibuprofen enantiomer to precipitate out of the mixture in the salt form. Optically active ibuprofen is racemized by being heated at 100.degree. C. to 300.degree. C. in the substantial absence of other materials.
    Type: Grant
    Filed: October 19, 1993
    Date of Patent: January 10, 1995
    Assignee: Hoechst Celanese Corporation
    Inventors: Apurba Bhattacharya, John R. Fritch, Carl D. Murphy, Larry D. Zeagler, Carina A. McAdams
  • Patent number: 5360688
    Abstract: A composite film article which is a flexible, heat resistant, polymeric film material having a non-opaque, partially translucent white surface side, having a visible light opacity of from about 0.90 to about 0.99; and a non-opaque, black surface side having a visible light opacity of less than 1.0, a transmission density of less than about 2.0 and a thickness less than about 5.0 microns. The article may be used as a base for images such that the images have a reduced optical dot gain.
    Type: Grant
    Filed: November 23, 1993
    Date of Patent: November 1, 1994
    Assignee: Hoechst Celanese Corporation
    Inventors: Robert J. von Trebra, Dennis J. Bellville
  • Patent number: 5348833
    Abstract: The invention relates to a positive-working colored photosensitive recording material for the production of a color test image, composed of a temporary layer carrier, a photosensitive layer containing dyestuff or pigment, binder and quinonediazide compound and an adhesive layer which can be activated by means of heat, wherein a release layer based on polyvinyl alcohol is present on the surface of the temporary layer carrier, the photosensitive layer comprises, as the quinonediazide compound, an esterification product of a compound containing one or more phenolic hydroxyl groups and o-quinonediazide-sulfonyl chloride, and, as the binder, a novolak-free phenolic polymer resin and/or a reaction product of the phenolic polymer resin with a monoisocyanate, and the adhesive layer compresses a alkali-insoluble organic polymer and an alkali-soluble polyester. The invention also relates to a process for the production of a color test image using the recording material described.
    Type: Grant
    Filed: September 4, 1992
    Date of Patent: September 20, 1994
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Dieter Mohr, Martin Benzing, Juergen Mertes, Guenter Hultzsch, Ine Gramm, Manfred Michel, Andreas Elsaesser, Shane Hsieh, David L. Siegfried