Patents Assigned to Hoechst AG
  • Patent number: 5616683
    Abstract: A process for maintaining or increasing the tensile strength of fibers of aromatic copolyamides which are formed from a major portion of para-monomers and are soluble in organic aprotic and polar solvents. The process involves storing the fibers in alkaline media after production by wet or dry spinning processes, after treatment of the dry or wet spun fibers, and storing the fibers in an aqueous environment having a pH of at least 10. The tensile strength of the fibers is retained or increased.
    Type: Grant
    Filed: January 13, 1994
    Date of Patent: April 1, 1997
    Assignee: Hoechst AG
    Inventors: Richard Neuert, Georg-Emerich Miess
  • Patent number: 5616779
    Abstract: The present invention relates to a process for the preparation of 2,5-di-phenylamino-terephthalic acid and its dialkyl esters of the formula ##STR1## in which R is a hydrogen atom or a methyl or an ethyl group, by reaction of a succinic acid dialkyl ester with a sodium alcoholate in xylene, treatment of the resulting 2,5-dihydroxy-cyclohexadiene-1,4-di-carboxylic acid dialkyl ester with acid and aniline, dehydrogenation of the resulting 2,5-di-phenylamino-dihydro-(3,6)-terephthalic acid dialkyl ester by means of oxygen, if appropriate hydrolysis of the 2,5-di-phenylamino-terephthalic acid dialkyl ester formed and liberation of the 2,5-di-phenylamino-terephthalic acid from the di-sodium salt formed. The 2,5-di-phenylamino-dihydro-(3,6)-terephthalic acid dialkyl ester is reacted with pure oxygen in the presence of an alkali metal ion and/or an alkaline earth metal ion. This significantly decreases undesirable impurities.
    Type: Grant
    Filed: March 2, 1995
    Date of Patent: April 1, 1997
    Assignee: Hoechst AG
    Inventor: Otto Arndt
  • Patent number: 5614626
    Abstract: The invention relates to compounds of the formula (I) ##STR1## which R is hydrogen or (C.sub.1 -C.sub.4)-alkyl, to a process for their preparation and to their use as electrophilic fluorinating agents.
    Type: Grant
    Filed: July 11, 1995
    Date of Patent: March 25, 1997
    Assignee: Hoechst AG
    Inventors: Ivan Cabrera, Wolfgang Appel
  • Patent number: 5597387
    Abstract: The present invention relates to water-soluble polyazo dyestuffs of the general formula I ##STR1## wherein Y, Z, m and M.sup..sym.1 to M.sup..sym.4 are as defined in claim 1, processes for dyeing leather and paper with the polyazo dyestuffs, and recording liquids and inks containing the polyazo dyestuffs.
    Type: Grant
    Filed: November 9, 1995
    Date of Patent: January 28, 1997
    Assignee: Hoechst AG
    Inventors: Wolfgang Bauer, Dieter Baumgart, Walter Zoller
  • Patent number: 5594145
    Abstract: The process for the preparation of 2(3H)-benzothiazolones which are optionally substituted on the benzene ring by reacting a 2-aminobenzothiazole which is optionally substituted on the benzene ring with a diazotization agent in the presence of aqueous hydrochloric acid, if appropriate with addition of a chloride, to give a diazonium chloride, reacting the diazonium chloride directly to give a 2-chlorobenzothiazole, which is optionally substituted on the benzene ring, and hydrolyzing the 2-chlorobenzothiazole, without intermediate isolation, at 120.degree.-200.degree. C. under reaction pressure.
    Type: Grant
    Filed: April 25, 1994
    Date of Patent: January 14, 1997
    Assignee: Hoechst AG
    Inventors: Klaus Forstinger, Heinrich Volk, Werner Wykypiel
  • Patent number: 5591893
    Abstract: The invention relates to a process for the preparation of polycarboxylic acids and derivatives thereof, the polycarboxylic acids prepared containing at least three carboxyl groups, comprising the steps(A) introducing one or more organic compounds, which contain nonaromatic carbon-carbon (C--C) double bonds, into water,(B) ozonolysis of the organic compounds in water by passing in an ozone-containing carrier gas,(C) addition of an aqueous hydrogen peroxide solution, to oxidatively work up the ozonolysis products produced in step (B), which comprises, in step (A), introducing the organic compound(s) into water having a pH of 7 or less than 7 and, in step (C), adding hydrogen peroxide in water without adding an organic solvent.
    Type: Grant
    Filed: October 27, 1993
    Date of Patent: January 7, 1997
    Assignee: Hoechst AG
    Inventors: J urgen Kulpe, Heinz Strutz
  • Patent number: 5591888
    Abstract: To produce tert-butyl chloroacetate by addition of chloroacetic acid to isobutene, the reaction is carried out in the absence of catalysts and solvents in a pressure vessel at a temperature of 80.degree. to 110.degree. C. under the pressure which establishes itself of 3 to 12 bar over a period of 1 to 12 hours. After the pressure vessel is cooled, the cooled product mixture is withdrawn and it is worked up by distillation under reduced pressure without prior neutralization.
    Type: Grant
    Filed: September 13, 1995
    Date of Patent: January 7, 1997
    Assignee: Hoechst AG
    Inventors: Andreas Seidel, Dieter Peters, Norbert Weferling, Dimitrios Mouratidis
  • Patent number: 5591877
    Abstract: Fluorinated carboxylic acids can be recovered from materials which contain them by releasing, if necessary, the carboxylic acids with sufficiently strong acids, esterifying the released acids and distilling off the esters. The esters can be advantageously directly hydrolyzed with aqueous ammonia solution to give the corresponding ammonium salts.
    Type: Grant
    Filed: May 3, 1995
    Date of Patent: January 7, 1997
    Assignee: Hoechst AG
    Inventors: Reinhold Obermeier, Gunter Stefaniak
  • Patent number: 5589589
    Abstract: A process and apparatus for screening cellulose ethers which have a finely fibrous or wad-like or woolly structure, wherein the process comprises the following steps:a) applying the cellulose ether (material to be screened) to a sieve surface,b) dividing the material to be screened into an screenable portion (acceptable size material or material passing through the sieve) and a circulating portion (oversize material or sieve surface tailings) with the aid of an agitated (preferably vibrating and/or tumbling) sieve surface,c) flushing through the agitated sieve surface from below, generally perpendicularly to the sieve surface, with an air flow,d) discharging (recovering) the acceptable size material, ande) discharging the circulating portion from the sieving system.The air flow inhibits clogging or plugging of or matting upon the sieve surface and is preferably directed upward by slit nozzles arranged below the sieve surface.
    Type: Grant
    Filed: April 11, 1995
    Date of Patent: December 31, 1996
    Assignee: Hoechst AG
    Inventors: Manfred Sponheimer, Guenther Welt, Manfred Ziegelmayer
  • Patent number: 5585216
    Abstract: Cyclically linked oligo- and polysaccharides having 3 to 100 monomeric saccharide units are used as charge control agents and charging improvers in electrophotographic toners and developers, in powders and powder coatings which can be sprayed triboelectrically or electrokinetically and in electret materials.
    Type: Grant
    Filed: May 26, 1995
    Date of Patent: December 17, 1996
    Assignee: Hoechst AG
    Inventors: R udiger Baur, Hans-Tobias Macholdt
  • Patent number: 5585508
    Abstract: The present invention relates to a polynuclear metallocene compound of the formula I ##STR1## a process for their preparation and their use as a catalyst for olefin polymerization.
    Type: Grant
    Filed: November 23, 1994
    Date of Patent: December 17, 1996
    Assignee: Hoechst AG
    Inventors: Frank K uber, Michael Aulbach, Bernd Bachmann, Walter Spaleck, Andreas Winter
  • Patent number: 5585489
    Abstract: Triphendioxazine compounds corresponding to the formula (1) ##STR1## in which Z is a radical of the formula (2) ##STR2## in which Y.sup.1 and Y.sup.2 each vinyl .beta.-hydroxyethyl or an ethyl radical which contains a substituent which can be eliminated under alkaline conditions in the .beta.-position, and in which Y.sup.1 and Y.sup.2 are not simultaneously .beta.-hydroxyethyl, W.sup.1 and W.sup.2 are both allyene having 2 to 6 carbon atoms, A is a covalent bond of a group of the formula --B.sup.1 --N(R.sup.3)--, in which R.sup.3 has one of the meanings of R.sup.1 and B.sup.1 is an aliphatic or aromatic bridge member, and in which the group--N(R.sup.1) --B.sup.1 --N(R.sup.3)-- can also be in total a bivalent saturated heterocyclic radical, and Z.sup.0 is hydrogen or a group of the formula (4) ##STR3## in which A.sup.0 is a covalent bond or a radical or the formula --N(R.sup.4)--B.sup.2 -- having the meaning corresponding to the above formula --B.sup.1 (NR.sup.3)-- are described.
    Type: Grant
    Filed: May 4, 1995
    Date of Patent: December 17, 1996
    Assignee: Hoechst AG
    Inventors: Werner H. Russ, Christian Schumacher
  • Patent number: 5576384
    Abstract: Production of low-emission dispersion paints, coating materials and synthetic resin dispersion plasters in the form of aqueous preparations based on aqueous synthetic resin dispersion copolymers derived from olefinically unsaturated monomers, having a pigment volume concentration (PVC) of at least 60% and containing water, fillers, pigments, synthetic resin dispersion copolymers and conventional auxiliaries, wherein the synthetic resin dispersion copolymers have a content of 0.05 to 2% by weight of monomer units derived from special unsaturated hydrolyzable organic silicon compounds and the aqueous copolymer dispersions possess a minimum film-forming temperature (MFT) of <10.degree. C., preferably <5.degree. C. and especially <2.degree. C., the aqueous preparations according to the invention contain <0.1% by weight of volatile non-aqueous constituents, based on the total non-volatile part of the preparations, and the pH of the aqueous preparations is in the range from 5.5 to 10.
    Type: Grant
    Filed: May 23, 1995
    Date of Patent: November 19, 1996
    Assignee: Hoechst AG
    Inventors: Ernst N olken, Helmut Braun, Michael Lonitz
  • Patent number: 5575821
    Abstract: A process for the dyeing of fiber materials with water-soluble anionic dyes, in particular those having a fiber-reactive group, is described, according to which dyeing is carried out using low-electrolyte or entirely electrolyte-free and/or low-alkali or entirely alkali-free dye solutions (dye liquors, printing pastes) and in which a fiber material is used which was modified by means of a saturated straight-chain or branched aliphatic or cycloaliphatic compound which is unsubstituted or substituted by one or more hydroxy groups and contains at least one primary, secondary or tertiary amino group or quaternary ammonium group and at least one hydrolyzable ester group, it also being possible for the aliphatic radical in this compound to be interrupted by one or more hetero groups.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: November 19, 1996
    Assignee: Hoechst AG
    Inventors: Andreas Schrell, Werner H. Russ, Thomas Riehm
  • Patent number: 5576454
    Abstract: Process for preparing phosphonic anhydrides of the formula (I) ##STR1## in which R is (C.sub.1 -C.sub.10)-alkyl which is unsubstituted or substituted by alkyl groups, alkoxy groups, fluorine, chlorine or bromine atoms, nitro groups, cyano groups, trifluoromethyl groups, phenyl groups, it being possible for the phenyl radical in turn to carry alkyl groups, alkoxy groups, fluorine, chlorine, bromine atoms, nitro groups, cyano groups or alkoxycarbonyl groups, and n.gtoreq.3, by reacting a phosphonic acid of the formula (II) ##STR2## in which R has the meaning given, with diketene, if appropriate at elevated temperature.
    Type: Grant
    Filed: October 28, 1994
    Date of Patent: November 19, 1996
    Assignee: Hoechst AG
    Inventor: G unter Roscher
  • Patent number: 5571934
    Abstract: Process for preparing solutions of polyhydroxy-fatty acid amides having good color qualityIn the process described, at least one sulfur compound from the group of dithionous acid is added in an active amount to the crude solutions, which are in general more or less brown in color, after which water-clear polyhydroxy-fatty acid amide products result.
    Type: Grant
    Filed: August 1, 1995
    Date of Patent: November 5, 1996
    Assignee: Hoechst AG
    Inventors: Bernd Papenfuhs, Reinhard Vybiral
  • Patent number: 5565534
    Abstract: The present invention relates to a process for the preparation of a polyolefin by polymerization of at least one olefin in the presence of a stereorigid metallocene compound containing, as ligands, at least two substituted or unsubstituted cyclopentadienyl groups bonded to one another via a monocyclic or polycyclic ring system, in which at least one cyclopentadienyl group is fused to the monocyclic or polycyclic ring system.
    Type: Grant
    Filed: December 21, 1994
    Date of Patent: October 15, 1996
    Assignee: Hoechst AG
    Inventors: Michael Aulbach, Bernd Bachmann, Gerhard Erker, Christian Psiorz, Frank Kuber, Frank Osan, Thomas Weller, Hans-Friedrich Herrmann
  • Patent number: 5563016
    Abstract: Ionic monomeric diallylammonium compounds having a targeted combination of diallylammonium cations with selected anions have particularly high and constant charge control properties and very good heat stabilities and dispersibilities.The compounds according to the invention are outstandingly suitable for use as colorless charge control agents in toners and developers for electrophotographic recording processes and for use as charge-improving agents in powders and paints for surface coating, in particular in triboelectrically or electrokinetically sprayed powder paints.
    Type: Grant
    Filed: June 5, 1995
    Date of Patent: October 8, 1996
    Assignee: Hoechst AG
    Inventors: R udiger Baur, Hans-Tobias Macholdt
  • Patent number: 5563271
    Abstract: Preparation of N-(2-sulfatoethyl)piperazine sulfate by reacting N-(2-hydroxyethyl)piperazine in a mixture of high- or relatively high-percentage sulfuric acid and oleum or chlorosulfonic acid at temperatures of about 80.degree. C. to about 250.degree. C., introducing the sulfation mixture formed into a water-miscible aliphatic alcohol and isolating the N-(2-sulfatoethyl)piperazine sulfate formed.
    Type: Grant
    Filed: March 15, 1995
    Date of Patent: October 8, 1996
    Assignee: Hoechst AG.
    Inventors: Michael Meier, Heinz-Georg Kautz, Andreas Schrell
  • Patent number: 5559216
    Abstract: An ecologically and economically advantageous process for preparing a disazo pigment of the formula (I) or a mixture of said disazo pigments ##STR1## where D.sup.1 and D.sup.2 are identical or different and each is unsubstituted phenyl, phenyl with from 1 to 5 substituents, unsubstituted naphthyl, naphthyl with from 1 to 3 substituents, unsubstituted anthraquinonyl, anthraquinonyl with from 1 to 3 substituents, or a radical of a fused aromatic heterocycle which contains from 1 to 3 identical or different heteroatoms from nitrogen or oxygen and sulfur and is unsubstituted or has from 1 to 3 substituents,R.sup.1 and R.sup.2 are identical or different and each is hydrogen, halogen, C.sub.1 -C.sub.4 -alkyl, C.sub.1 -C.sub.4 -alkoxy, C.sub.1 -C.sub.
    Type: Grant
    Filed: September 1, 1993
    Date of Patent: September 24, 1996
    Assignee: Hoechst AG
    Inventors: Ruediger Jung, Joachim Weide, Hans J. Metz