Patents Assigned to Hoechst Celanese
  • Polarizer films comprising wholly aromatic liquid crystalline polymers and dichroic dyes
    Patent number: 5738803
    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: December 14, 1995
    Date of Patent: April 14, 1998
    Assignee: Hoechst Celanese Corp
    Inventors: James P. Shepherd, Sunny S. Shen, Brian B. Marr, Larry F. Charbonneau
  • Resolution of racemic mixtures using polymers containing chiral units
    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
  • Polymeric compositions having a temperature-stable dielectric constant
    Patent number: 5739193
    Abstract: A polymeric composition having a high dielectric constant which varies little with temperature is made from a thermoplastic polymer, a high dielectric ceramic having a dielectric constant of at least about 50 at 1.0 Ghz and 20.degree. C., and a second ceramic material having a dielectric constant of at least about 5.0 at 1.0 GHz and 20.degree. C., where the high dielectric ceramic and the second ceramic material have temperature coefficients that are opposite in sign from one another.
    Type: Grant
    Filed: May 7, 1996
    Date of Patent: April 14, 1998
    Assignee: Hoechst Celanese Corp.
    Inventors: Lak M. Walpita, Paul N. Chen, Sr., Harris A. Goldberg, Christopher Zipp
  • Process for preparing quinazolones
    Patent number: 5739330
    Abstract: The present invention provides a process for preparing a quinazolone which comprises the steps of (a) dehydrating a N-acyl beta amino acid in the presence of a dehydration agent and an organic solvent for a sufficient period of time and under suitable temperature and pressure conditions to form an oxazone (b) adding a carboxylic acid and a primary amine salt of a carboxylic acid to said oxazone to form a mixture, (c) distilling azeotropically said mixture for a suitable period of time and under suitable temperature and pressure conditions to substantially remove said dehydration agent and said organic solvent, and (d) heating the product of step (c) for a sufficient period of time and under suitable temperature and pressure conditions to form said quinazolone.
    Type: Grant
    Filed: February 5, 1996
    Date of Patent: April 14, 1998
    Assignee: Hoechst Celanese Corporation
    Inventors: Apurba Bhattacharya, Diane E. Allen
  • Reusable bale wrap kit for compressed, resilient fibers
    Patent number: 5732531
    Abstract: A method for wrapping a bale of compressed, resilient fibers comprises the steps of: providing a reusable bale wrap kit. The kit includes at least two pieces. Each piece, when joined with the other piece, is adapted for substantially enclosing and containing the bale of compressed, resilient fibers. Mushroom and loop fasteners are located along an edge portion of each piece and are adapted for joining the pieces to one another. Uncompressed, resilient fibers are provided. A portion of the uncompressed, resilient fibers are surrounded with the kit. Those fibers are compressed, and the mushroom and loop fasteners are engaged.
    Type: Grant
    Filed: October 30, 1995
    Date of Patent: March 31, 1998
    Assignee: Hoechst Celanese Corporation
    Inventors: San de Silva, William S. Sanderson
  • Elastomeric compositions
    Patent number: 5731380
    Abstract: An elastomeric composition comprising:(A) a polyester elastomer;(B) a thermoplastic polyurethane elastomer; and(C) a multiphase composite interpolymer comprising an elastomeric first phase, a final rigid thermoplastic phase and, optionally, one or more intermediate phases,wherein components (A) and (B) combined are present in the composition in an amount of from about 55 to about 90 percent by weight, based on the total weight of components (A), (B) and (C); and wherein the ratio by weight of component (A) to component (B) is from about 1:5 to about 8:1.
    Type: Grant
    Filed: April 11, 1997
    Date of Patent: March 24, 1998
    Assignee: Hoechst Celanese Corporation
    Inventor: Michael D. Golder
  • Vinyl acetate process utilizing a palladium-gold-copper catalyst
    Patent number: 5731457
    Abstract: A process is disclosed for the production of vinyl acetate by reaction of ethylene, oxygen and acetic acid as reactants comprising contacting said reactants and a non-halogen containing copper compound with a catalyst comprising a porous support on the porous surfaces of which is deposited catalytically effective amounts of metallic palladium, gold and copper. During the process to prepare vinyl acetate, a stream of alkali metal acetate is preferably passed over the catalyst. The process results in higher vinyl acetate selectivity and productivity due to lower CO.sub.2 selectivity during the life of the catalyst, and/or longer catalyst life.
    Type: Grant
    Filed: June 3, 1997
    Date of Patent: March 24, 1998
    Assignee: Hoechst Celanese Corporation
    Inventors: Ioan Nicolau, Jerry A. Broussard, Philip M. Colling
  • Process for improving productivity of a carbonylation catalyst solution by removing corrosion metals
    Patent number: 5731252
    Abstract: A process for treating low water content carbonylation catalyst solutions which contain a rhodium component and an alkali metal component to remove metallic corrosion products is disclosed. The process comprises contacting the catalyst solution with an ion exchange resin, preferably in the lithium form, and a sufficient amount of water to decrease the concentration of alkali metal ions to optimize removal of corrosion metal products.
    Type: Grant
    Filed: January 21, 1997
    Date of Patent: March 24, 1998
    Assignee: Hoechst Celanese Corporation
    Inventors: R. Jay Warner, Jerry Allen Broussard
  • Process for the preparation of thermotropic aromatic polyesters directly from dialkyl aromatic esters
    Patent number: 5731401
    Abstract: A new process is provided for the formation of aromatic polyesters directly from the reaction of dialkyl ester of an aromatic carboxylic acid with dihydric phenols. The polycondensation is carried out in the presence of (a) a condensing agent; (b) a catalyst selected from the group consisting of derivatives of Group I metals, derivatives of Group IV A metals, derivatives of Group IV B metals, and mixtures thereof; and (c) a co-catalyst selected from the group consisting of methanesulfonic acid, sulfuric acid, p-toluenesulfonic acid, alkanoic acid having the formula, C.sub.n H.sub.x F.sub.y COOH, where n is an integer from 1 to 4, x and y are integers from 0 to 2n+1, and the sum of x and y is 2n+1, and mixtures thereof; at suitable temperature and pressure conditions and for a sufficient period of time to form the aromatic polyester.
    Type: Grant
    Filed: September 30, 1996
    Date of Patent: March 24, 1998
    Assignee: Hoechst Celanese Corp.
    Inventors: Balaram Gupta, Matthew J. Bylicki
  • Thermoplastic three-dimensional fiber network
    Patent number: 5731062
    Abstract: Three dimensional fiber networks which are semi-rigid and dimensionally stable are made from textile fabrics that have projections and optional depressions which are compressible and return to their original shape after being compressed. The fiber networks are made by the thermo-mechanical deformation of textile fabrics that are in turn made from thermoplastic fibers. The fiber networks have particular utility as cushioning and impact absorbing materials.
    Type: Grant
    Filed: December 22, 1995
    Date of Patent: March 24, 1998
    Assignee: Hoechst Celanese Corp
    Inventors: Dai W. Kim, Joseph Steven Wiley Haas, William Edward Bessey
  • In-line silicone coated polyester film and a process for coating the film
    Patent number: 5728339
    Abstract: A silicone release film including an oriented polyester film having a coating thereon in an amount sufficient to act as a silicone release film. The aqueous coating comprises glycidoxy silane and an aqueous based thermosetting silicone release composition. The minimum amount of glycidoxy silane present in the coating is at least 1.0% by weight of the silicone solids. Typical glycidoxy silanes are glycidoxypropyltrimethoxysilane or glycidoxypropyltriethoxysilane. A process for coating a polyester film with a silicone coating is also disclosed, where the coating occurs in-line, during the manufacturing process for the film before it is heat-set.
    Type: Grant
    Filed: February 14, 1996
    Date of Patent: March 17, 1998
    Assignee: Hoechst Celanese Corporation
    Inventor: Grover L. Farrar
  • Coating of preceramic articles with silicon and/or carbon during pyrolysis to ceramic
    Patent number: 5725950
    Abstract: A process for the preparation of carbon and/or silicon coated ceramic fibers is disclosed involving contact of a preceramic fiber with a hydrocarbon or a silane which decomposes at a temperature no higher than 500.degree. C. at 1 atmosphere.
    Type: Grant
    Filed: September 19, 1986
    Date of Patent: March 10, 1998
    Assignee: Hoechst Celanese Corp.
    Inventors: Paul Foley, Linda C. Sawyer
  • Photoactive coumarin derivatives
    Patent number: 5726295
    Abstract: A new class of 3,4-dihydrocoumarin derivatives which are useful as photoactive compounds in a wide variety of applications including photoresists and other opto-electronic applications are disclosed and claimed. Preferred embodiments include ether, ester, carbonate, and sulfonate derivatives of 5-hydroxy, 6-hydroxy, and 7-hydroxy-3-diazo-4-oxo-3,4-dihydrocoumarins. These compounds exhibit very high photosensitivity in the deep ultraviolet (DUV) region (ca. 250 nm), and therefore, are useful as photoactive compounds in DUV photoresist formulations.
    Type: Grant
    Filed: March 7, 1997
    Date of Patent: March 10, 1998
    Assignee: Hoechst Celanese Corp.
    Inventors: Mohammad Aslam, Michael T. Sheehan, Debasish Kuila
  • Process for preparing photoactive coumarin derivatives
    Patent number: 5726296
    Abstract: Novel processes for the preparation of a new class of coumarin derivatives, which are useful as photoactive compounds in a wide variety of applications including photoresists and other opto-electronic applications, are disclosed and claimed. The process involves a multi-step synthetic method for the preparation of ether, ester, carbonate, or sulfonate derivative of 5-hydroxy, 6-hydroxy, or 7-hydroxy-3-diazo-4-oxo-3,4-dihydrocoumarin starting from the corresponding dihydroxyacetophenone. The compounds formed from the process of the present invention exhibit very high photosensitivity in the deep ultraviolet (DUV) region (ca. 250 nm), and therefore, are useful as photoactive compounds in DUV photoresist formulations.
    Type: Grant
    Filed: March 7, 1997
    Date of Patent: March 10, 1998
    Assignee: Hoechst Celanese Corp.
    Inventors: Mohammad Aslam, Michael T. Sheehan, Debasish Kuila
  • Cut resistant fabric, apparel, and yarn
    Patent number: 5721179
    Abstract: A cut resistant fabric is made from woven or knitted yarn; the yarn includes a cut resistant fiber having a tenacity of less than about 10 grams/denier. A cut resistant fabric is made from woven or knitted yarn. The yarn includes a polyethylene fiber having a tenacity of less than about 10 grams/denier and a molecular weight of about 100,000. The yarn may be in the form of a composite yarn having a core and a wrap. The polyethylene fiber is in the wrap.
    Type: Grant
    Filed: February 2, 1996
    Date of Patent: February 24, 1998
    Assignee: Hoechst Celanese Corporation
    Inventors: Lie Shi, Ralph Stephen Blake
  • Monolithic LCP polymer microelectronic wiring modules
    Patent number: 5719354
    Abstract: The invention provides a multilayer microelectronic circuit board including a laminate of a plurality of circuit layers containing conductive vias within the layers or a combination of conductive vias and conductive wiring patterns on a surface of the layers, the layers comprising a first liquid crystal polymer and, interposed between said circuit layers, a layer of second liquid crystal polymer having a melting point of at least about 10.degree. C. lower than the melting point of the first liquid crystal polymer.
    Type: Grant
    Filed: September 16, 1994
    Date of Patent: February 17, 1998
    Assignees: Hoechst Celanese Corp., Kuraray Company Ltd.
    Inventors: Randy Douglas Jester, Edwin Charles Culbertson, Detlef M. Frank, Sherman Hall Rounsville, John Arthur Penoyer, Takeichi Tsugaka, Minoru Onodera, Toshiaki Sato, Toru Sanefuji
  • Pressure drop tester for filter rods
    Patent number: 5719328
    Abstract: A device is provided for testing a pressure drop across a cigarette filter rod. The device includes an expansible sleeve for encapsulating a filter rod and a two stage vacuum pump connected thereto. A first controllable valve connects the outer surface of the sleeve to the vacuum pump to expand the sleeve so that a filter rod can be inserted. The first controllable valve also connects the end of the sleeve to the vacuum pump so that a measurable pressure drop is created across the filter rod. A second controllable valve is connected between an exhaust port of the vacuum pump and the end of the sleeve so that, after the testing has been completed, the filter rod will be ejected from the sleeve. The pressure testing device is thus self contained and does not require an external source of vacuum or compressed air.
    Type: Grant
    Filed: June 25, 1996
    Date of Patent: February 17, 1998
    Assignee: Hoechst Celanese Corporation
    Inventor: Joseph D. Gombash, Jr.
  • Method for solvent extraction using a dual-skinned asymmetric microporous membrane
    Patent number: 5714072
    Abstract: The instant invention is directed to a method of solvent extraction. The steps of the method include: providing a dual-skinned asymmetric membrane; providing a feed containing a solute; and providing a solvent. The feed and the solvent are contacted across the membrane. The solute of the feed is extracted, and forming thereby a raffinate and an extract.
    Type: Grant
    Filed: November 6, 1995
    Date of Patent: February 3, 1998
    Assignee: Hoechst Celanese Corporation
    Inventors: Bradley W. Reed, Kamalesh K. Sirkar
  • Process for preparing substituted aryls
    Patent number: 5710282
    Abstract: The present invention provides a novel one-step process for preparing substituted aryls which can be used as end-capping monomers for preparing highly branched macromolecule polymers that have highly controlled molecular architectures. The process comprises the steps of (a) reacting an aromatic acid with an activating carbodiimide for a sufficient period of time and under suitable conditions of temperature and pressure to form an activated aromatic intermediate, and (b) reacting said intermediate with a suitable nucleophile for a sufficient period of time and under suitable conditions of temperature and pressure to form said substituted aryl compound.
    Type: Grant
    Filed: August 18, 1995
    Date of Patent: January 20, 1998
    Assignee: Hoechst Celanese Corporation
    Inventors: Kathleen Nelson Juneau, Richard Vicari, Carl David Murphy
  • Thermally expandable, viscosity modified wax compositions and method of use in actuators
    Patent number: 5709740
    Abstract: A thermally expandable wax composition and its use in polymer-based actuators is disclosed and claimed. The compositions are wax-based and include conductive filler as well as a viscosity modifier to stabilize the composition against segregation. Optionally included are thermoxidative stabilizers.
    Type: Grant
    Filed: February 23, 1996
    Date of Patent: January 20, 1998
    Assignee: Hoechst Celanese Corp.
    Inventors: M. Ishaq Haider, James E. Kuder, Barbara J. Long, Joseph D. Menczel, James B. Stamatoff, Michael Bayer