Patents by Inventor Stefan A. Weiss

Stefan A. Weiss 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).

  • Patent number: 5126269
    Abstract: An apparatus is disclosed that separates and removes to an external source, spent cell culture media from a cell culture media and cell culture mixture. The apparatus generally comprises a culture vessel, a filter member, wherein the filter member is positioned in the culture vessel to form an outside region and an inside region. Further provided is a tube member. The tube member being positioned in the inside region and having an opening therein to thereby remove the spent cell culture media brought into the inside region. Further disclosed is a structure for rotating the filter member around the tube member and a structure for sealing the outside region from the inside region when the filter member is rotating around the tube member.
    Type: Grant
    Filed: September 13, 1990
    Date of Patent: June 30, 1992
    Assignee: Life Techologies, Inc.
    Inventors: Richard Fike, Stefan Weiss, Patrick Pomeroy
  • Patent number: 5064908
    Abstract: Oxidized polyethylenes useful as lubricants in the extrusion of polyvinyl chloride are prepared by oxidation of finely divided polyethylene of high density at elevated temperatures with an oxidation gas of air and/or oxygen, the polyethylene used containing from 0.015 to 0.5% by weight of a free radical former organic compound in admixture and being contacted per hour with an oxidation gas which per kilogram of polyethylene contains from 30 to 600, in particular from 80 to 300, mg of ozone, with or without a reduced pressure treatment at elevated temperatures after the oxidation.
    Type: Grant
    Filed: November 6, 1990
    Date of Patent: November 12, 1991
    Assignee: BASF Aktiengesellschaft
    Inventors: Ludwig Schuster, Albert Hettche, Werner Liedy, Stefan Weiss, Leo Ehemann
  • Patent number: 5034096
    Abstract: The present invention provides a process for bleaching and delignifying cellulose-containing products with peroxides and/or oxygen and/or ozone, wherein there is additionally used 0.01 to 2.5% by weight of cyanamide and/or cyanamide salts, referred to the dry weight of the cellulose.
    Type: Grant
    Filed: December 9, 1986
    Date of Patent: July 23, 1991
    Assignee: SKW Trostberg Aktiengesellschaft
    Inventors: Benedikt Hammer, Horst Michaud, Stefan Weiss
  • Patent number: 4956503
    Abstract: A process for the preparation of N-cyanoethanimidic acid esters by reacting orthoacetic acid esters with cyanamide. The reaction is carried out in alcoholic solution in the presence of an acid catalyst. N-cyanoethanimidic acid esters can be prepared in this manner in a high yield and high state of purity, with a low technical outlay and in an environmentally safe manner, free of dangerous by-products.
    Type: Grant
    Filed: April 18, 1989
    Date of Patent: September 11, 1990
    Assignee: SKW Trostberg Aktiengesellschaft
    Inventors: Stefan Weiss, Helmut Krommer, Karl-Heinz Neuhauser
  • Patent number: 4889897
    Abstract: Oxidized polyethylenes useful as water-emulsifiable waxes and as lubricants in the extrusion of polyvinyl chloride are prepared by oxidizing finely divided polyethylene of high density at elevated temperatures with an oxidation gas of air and/or oxygen, the oxidation gas supplied per hour containing not less the 100 mg of ozone per kilogram of polyethylene, by performing the oxidiation in a paddle dryer and passing the oxidation gas into the free gas space above the polyethylene, the temperature in the paddly dryer preferably being continuously adjusted to from 1.degree. to 2.degree. C. below the softening point of the polyethylene.
    Type: Grant
    Filed: June 15, 1988
    Date of Patent: December 26, 1989
    Assignee: BASF Aktiengesellschaft
    Inventors: Ludwig Schuster, Albert Hettche, Werner Liedy, Stefan Weiss, Leo Ehemann
  • Patent number: 4750933
    Abstract: An aqueous wax dispersion for floor care contains a mixture of an aqueous secondary dispersion of an ethylene copolymer wax, having a specific MFI, and an aqueous primary dispersion together with plasticizers, leveling agents and water, and an ethylene copolymer wax in the form of an aqueous secondary dispersion is used for floor emulsions.
    Type: Grant
    Filed: October 2, 1986
    Date of Patent: June 14, 1988
    Assignee: BASF Aktiengesellschaft
    Inventors: Franz Brandstetter, Walter Ziegler, Wolfram Dietsche, Stefan Weiss, Albert Hettche, Otto Kuehneweg
  • Patent number: 4714602
    Abstract: The present invention relates to a process for the preparation of solid sodium hydrogen cyanamide by reacting cyanamide with sodium hydroxide in aqueous solution, the aqueous solution or suspension containing sodium hydrogen cyanamide being concentrated to dryness with the aid of a drier device which uses heating gases, preferably, a spray drier or atomization drier, and, if appropriate, the product then being dried. A pulverulent product with good flow properties, purity and storage stability is thereby obtained in an industrially simple manner.
    Type: Grant
    Filed: July 16, 1986
    Date of Patent: December 22, 1987
    Inventors: Helmut Krommer, Karl-Heinz Neuhauser, Stefan Weiss
  • Patent number: 4693909
    Abstract: A liquid preservative for plated or unplated metal surfaces and surfaces of coatings, in the form of an aqueous wax dispersion which contains a special ethylene/acrylic acid copolymer wax, consisting of from 8 to 25% by weight of acrylic acid units and from 92 to 75% by weight of ethylene units, in partially or completely neutralized form, if appropriate as a mixture with waxes based on polyethylene oxidation products and/or hydrocarbon waxes, the use of this special ethylene/acrylic acid copolymer wax for preserving plated or unplated metal surfaces and surfaces of coatings, and a process for temporarily preserving metal surfaces and surfaces of coatings.
    Type: Grant
    Filed: March 24, 1986
    Date of Patent: September 15, 1987
    Assignee: BASF Aktiengesellschaft
    Inventors: Walter Ziegler, Wolfram Dietsche, Stefan Weiss, Richard Mueller, Albert Hettche, Klaus Glaser, Christos Vamvakaris
  • Patent number: 4680327
    Abstract: Stabilizers consisting of (a) 2,5,7,8-tetramethyl-2-(2'-stearyloxyethyl)-chroman and (b) glyceryl stearate, glyceryl hydroxystearate, partial esters of stearic acid with condensates of glycerol and trimethylolpropane, triglyceryl stearate and/or tetraglyceryl stearate, with or without further conventional additives, the weight ratio of (a) to (b) being from 10:1 to 1:10, give improved stabilization to discoloration and superior stability during processing when used in plastics such as polyethylene or polypropylene.
    Type: Grant
    Filed: January 29, 1986
    Date of Patent: July 14, 1987
    Assignee: BASF Aktiengesellschaft
    Inventors: Albert Hettche, Stefan Weiss, Hubert Trauth, Peter Lechtken, Michael Horner
  • Patent number: 4621109
    Abstract: 2,3-Dihydrobenz-4-oxa-1-thiins of the general formula I ##STR1## where R.sup.1, R.sup.2 and R.sup.3 are each hydrogen, methyl or methoxy, and R.sup.2 and R.sup.3 together may furthermore be a fused benzene ring, R.sup.4 is hydrogen or an m-valent aliphatic hydrocarbon radical which may be interrupted by sulfur and /or carry thiol groups as substituents, or is halogen when n is zero, X is --O--, --S-- or --O--CO--, m is 1 or 2 and n is zero or 1, are useful as antioxidants for organic materials.
    Type: Grant
    Filed: June 11, 1985
    Date of Patent: November 4, 1986
    Assignee: BASF Aktiengesellschaft
    Inventors: Peter Lechtken, Hubert Trauth, Stefan Weiss, Albert Hettche
  • Patent number: 4614604
    Abstract: A lubricant for shaping polyvinyl chloride, which contains esters of oligomers of trihydric, tetrahydric, pentahydric or hexahydric aliphatic alcohols, having 3 or more monomer units, with saturated or unsaturated C.sub.8 -C.sub.36 -fatty acids, from 30 to 100% of the alcoholic hydroxyl groups being esterified.
    Type: Grant
    Filed: July 22, 1985
    Date of Patent: September 30, 1986
    Assignee: BASF Aktiengesellschaft
    Inventors: Herbert Helfert, Wolf-Dieter Balzer, Guenter Hatzmann, Wolfram Dietsche, Albert Hettche, Stefan Weiss
  • Patent number: 4604471
    Abstract: Furan-3-carbohydroxamates of the formula ##STR1## where R.sup.1 is alkyl, unsubstituted or substituted cycloalkyl or unsubstituted or substituted phenyl, R.sup.2 is methyl or ethyl, R.sup.3 and R.sup.4 independently of one another are each hydrogen, bromine, chlorine, unsubstituted or substituted alkyl, or --CH.sub.2 --COOR.sup.5, where R.sup.5 is unsubstituted or substituted alkyl, and Me is divalent nickel or cobalt, stabilize plastics against the action of light, oxygen and heat. The compounds (I) have only slight intrinsic color.
    Type: Grant
    Filed: November 21, 1984
    Date of Patent: August 5, 1986
    Assignee: BASF Aktiengesellschaft
    Inventors: Peter Neumann, Michael Thomas, Stefan Weiss, Hubert Trauth
  • Patent number: 4603205
    Abstract: Novel furancarboxylic acid derivatives of the general formula ##STR1## where R.sup.1, R.sup.2 and R.sup.3 independently of one another are each hydrogen, C.sub.1 -C.sub.8 -alkyl, cyclohexyl or phenyl, but not more than two of these radicals are simultaneously hydrogen, and R.sup.4 is a radical of the formula --NR.sup.5 R.sup.6, ##STR2## or OR.sup.6, where A is a bridge member, R.sup.5 is hydrogen, C.sub.2 -C.sub.6 -alkenyl, C.sub.5 -C.sub.7 -cycloalkyl or C.sub.1 -C.sub.12 -alkyl which may or may not be interrupted by 1, 2 or 3 oxygen atoms, and R.sup.6 is a radical of the formula ##STR3## where R.sup.7, R.sup.8, R.sup.9 and R.sup.10 are each C.sub.1 -C.sub.4 -alkyl, or R.sup.7 and R.sup.8 or R.sup.9 and R.sup.10 together form a tetramethylene or pentamethylene bridge, and R.sup.11 is hydrogen, C.sub.1 -C.sub.8 -alkyl, C.sub.3 -C.sub.8 -alkenyl, C.sub.2 -C.sub.4 -hydroxyalkyl or aralkyl, and their salts are useful as light stabilizers for organic polymers, in particular olefin polymers.
    Type: Grant
    Filed: December 13, 1984
    Date of Patent: July 29, 1986
    Assignee: BASF Aktiengesellschaft
    Inventors: Peter Neumann, Reinhard Helwig, Stefan Weiss, Hubert Trauth
  • Patent number: 4587337
    Abstract: The present invention relates to a process for the preparation of 2-amino-s-triazines in three stages. In the first stage nitriles, alcohols and hydrogen chloride are reacted to form the corresponding imido-ester hydrochlorides. In the second stage, the imido-ester hydrochlorides are reacted with cyanamide in the aqueous phase to form the N-cyanimido-esters, which comprises carrying out the first stage in the presence of acetic acid esters and the second stage in an aqueous solution which has been brought to a pH value of 5-8 by addition of bases, and reacting the N-cyanimido-esters with O-alkylisourea, S-alkylisothiourea, guanidine or amidine salts in the presence of a base in the third stage. The 2-amino-s-triazines can be prepared in a high purity and with good yields in this manner.
    Type: Grant
    Filed: March 25, 1985
    Date of Patent: May 6, 1986
    Assignee: SKW Trostberg Aktiengesellschaft
    Inventors: Stefan Weiss, Helmut Krommer
  • Patent number: 4477421
    Abstract: The present invention provides a process for increasing the storage stability of an aqueous solution containing 20 to 80% by weight cyanamide, wherein the aqueous cyanamide solution is mixed with 0.005 to 0.5% by weight of divalent magnesium cations, referred to the cyanamide solution, in the form of at least one inorganic and/or organic magnesium salt.
    Type: Grant
    Filed: May 10, 1983
    Date of Patent: October 16, 1984
    Assignee: SKW Trostberg Aktiengesellschaft
    Inventor: Stefan Weiss
  • Patent number: 4459388
    Abstract: A process for the preparation of water-emulsifiable polyethylene by oxidizing high density polyethylene, at below the softening point of the polyethylene, in the presence of oxygen, wherein the oxidation is carried out in a fluidized bed reactor, using a polyethylene which beforehand has been heated, with exclusion of oxygen, in the presence of a compound which forms free radicals.
    Type: Grant
    Filed: February 19, 1982
    Date of Patent: July 10, 1984
    Assignee: BASF Aktiengesellschaft
    Inventors: Albert Hettche, Stefan Weiss, Peter Miederer, Lutz Goethlich, Juergen Ciprian
  • Patent number: 4438008
    Abstract: A lubricant for molding chlorine-containing thermoplastics, which contains ethylene/acrylic acid or ethylene/maleic acid copolymers esterified, in a molar ratio of carboxyl groups to alcoholic hydroxyl groups of from 1:0.2 to 1:1, with C.sub.1 -C.sub.20 -aliphatic alcohols which may or may not contain ether groups, the copolymers, prior to esterification, having a mean molecular weight of from 500 to 10,000 and containing from 2 to 15% by weight of acrylic acid or from 1 to 8% by weight of maleic acid as copolymerized units, the percentages being based on copolymer.
    Type: Grant
    Filed: February 12, 1982
    Date of Patent: March 20, 1984
    Assignee: BASF Aktiengesellschaft
    Inventors: Dieter Oeder, Walter Ziegler, Manfred Daeuble, Wolfram Dietsche, Albert Hettche, Stefan Weiss
  • Patent number: 4417035
    Abstract: Water-emulsifiable hard waxes consisting of homogeneous copolymers of ethylene with from 1 to 8% by weight, based on copolymer, of one or more .alpha.-olefinically unsaturated C.sub.3 -C.sub.8 -carboxylic acids, and having the following characteristic data:Melt index=1,500 to 20 MFI units, measured at 160.degree. C. under 325 g loadAcid number=10-60Hoppler hardness=400-800 bar, measured at 23.degree. C. by DGF standard method M-III 9a (57).
    Type: Grant
    Filed: November 13, 1981
    Date of Patent: November 22, 1983
    Assignee: BASF Aktiengesellschaft
    Inventors: Dieter Oeder, Wolfram Dietsche, Stefan Weiss, Walter Ziegler, Peter Kueppers, Albert Hettche
  • Patent number: 4406705
    Abstract: Water-emulsifiable hard waxes consisting of homogeneous terpolymers of ethylene with--based on weight of terpolymer--from 1 to 8% by weight of C.sub.3 -C.sub.8 -olefinically unsaturated carboxylic acids and from 0.5 to 10% by weight of C.sub.1 -C.sub.12 -alkyl esters of such unsaturated carboxylic acids and having a Staudinger index, determined according to DIN 53,728, of from 5 to 55, an acid number of from 8 to 62 and a Hoppler hardness, measured by DFG standard method M-III-9a(57), at 23.degree. C., of from 250 to 800 bar, are obtained by copolymerizing ethylene with olefinically unsaturated C.sub.3 -C.sub.8 -carboxylic acids and esters of such acids with C.sub.1 -C.sub.12 -alkanols in a continuous process in the presence of a free radical initiator at from 150.degree. to 300.degree. C. under a pressure of from 1,000 to 3,000 bar, using a weight ratio of ethylene:acid:acrylate of from 500:1:1 to 20:1:1, in a one-phase polymerization medium in which the monomers are soluble, in the presence of from 0.
    Type: Grant
    Filed: February 16, 1982
    Date of Patent: September 27, 1983
    Assignee: BASF Aktiengesellschaft
    Inventors: Dieter Oeder, Wolfram Dietsche, Stefan Weiss, Walter Ziegler, Albert Hettche
  • Patent number: 4126664
    Abstract: The storage stability of strong or concentrated, aqueous solutions of cyanamide, even those conventionally stabilized with acid, is enhanced by small amounts of lower alkyl esters of carboxylic acids having preferably a pK.sub.a.sup.25.degree. value of 3.8 or less.
    Type: Grant
    Filed: September 1, 1977
    Date of Patent: November 21, 1978
    Assignee: Suddeutsche Kalkstickstoff-Werke Aktiengesellschaft
    Inventor: Stefan Weiss