Patents by Inventor Holger Buchwald

Holger Buchwald 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: 6547860
    Abstract: A process for the manufacture of a triboelectrically charged nonwoven, wherein a fiber blend made of polyacrylnitrile fibers with a titer of ≦1.7 dtex and of polyolefine fibers with a titer of ≦1.7 dtex is freed from lubricating agents and antistatic agents by washing, is dried down to a moisture content of <1% by weight and is carded on a longitudinal or randomizing card into a triboelectrically charged web with a mass per area unit of 15-80 g/m2. This web is taken off by two simultaneously running rolls and a transfer roll, so that the web is laid on to a conveyor in machine direction, and bonded directly inside a bonding set, the unbonded web being forwarded via 1 to 3 points of transfer only.
    Type: Grant
    Filed: November 21, 2001
    Date of Patent: April 15, 2003
    Assignee: Firma Carl Freudenberg
    Inventors: Holger Buchwald, Karl-Heinz Morweiser, Klaus Veeser
  • Publication number: 20020121194
    Abstract: A process for the manufacture of a triboelectrically charged nonwoven, wherein a fiber blend made of polyacrylnitrile fibers with a titer of ≦1.7 dtex and of polyolefine fibers with a titer of ≦1.7 dtex is freed from lubricating agents and antistatic agents by washing, is dried down to a moisture content of <1% by weight and is carded on a longitudinal or randomizing card into a triboelectrically charged web with a mass per area unit of 15-80 g/m2. This web is taken off by two simultaneously running rolls and a transfer roll, so that the web is laid on to a conveyor in machine direction, and bonded directly inside a bonding set, the unbonded web being forwarded via 1 to 3 points of transfer only.
    Type: Application
    Filed: November 21, 2001
    Publication date: September 5, 2002
    Inventors: Holger Buchwald, Karl-Heinz Morweiser, Klaus Veeser
  • Patent number: 4820560
    Abstract: Disclosed is a swellable nonwoven fabric strip for a cable wrapping having a specific resistance of 3,000 .OMEGA..multidot.cm.sup.2 or less and a method for its manufacture. The strip is in the form of a fibrous flat material without perceptible layered construction, wherein the fibers are aligned mainly lengthwise of the strip and are 95 to 75 wt.- % in the form of viscose fibers and 5 to 25 wt.- % in the form of shrunken polyvinylalcohol fibers soluble in water beginning at 80.degree. C. The flat material is uniformly impregnated with a binding agent which under the action of water loses its ability to adhere. The strip contains swelling powder particles which swell upon the access of water but do not dissolve, the swelling agent being distributed in an amount of 20 to 40 g/m.sup.2. The strip is capable of swelling at the place of access of the water to at least 90% of its achievable thickness in approximately one minute.
    Type: Grant
    Filed: May 21, 1987
    Date of Patent: April 11, 1989
    Assignee: Firma Carl Freudenberg
    Inventors: Holger Buchwald, Ingrid Schaffert
  • Patent number: 4724501
    Abstract: A jacket for a floppy disk consists essentially of a porous nonwoven material both for a writable cover function and a soft, fibrous liner function.
    Type: Grant
    Filed: March 25, 1985
    Date of Patent: February 9, 1988
    Assignee: Firma Carl Freudenberg
    Inventors: Holger Buchwald, Werner Schafer, Peter Hartwig
  • Patent number: 4465723
    Abstract: Disclosed herein is a fixation insert having improved resistance to back-riveting (flash-through) and a method for the manufacture thereof, consisting of a planar textile structure of natural and/or synthetic threads and a coating, applied to the front side, of a thermally softenable adhesive compound, where the planar structure has at least on the back side a layer of fibers which extend beyond the surface of the planar structure predominantly perpendicularly, and where the fibers are elastically resilient. The fibers are elastically connected to the threads and are deposited thereon in an electrostatic field.
    Type: Grant
    Filed: June 11, 1982
    Date of Patent: August 14, 1984
    Assignee: Firma Carl Freudenberg
    Inventors: Jurgen Knoke, Holger Buchwald, Jurgen Fehlhaber
  • Patent number: 4430372
    Abstract: Described herein is a nonwoven fabric with improved hot-press properties and a method for manufacturing the same, consisting of natural and/or synthetic fibers which are united to form an open thread structure and are coated entirely or partially with a coating of an elastic bonding agent, where the ends of short fibers protruding beyond the surface of the nonwoven fabric in nap-fashion on one or both sides are bound into the coating. The short fibers are introduced into the thread structure in an electrostatic field and may be distributed regularly or irregularly.
    Type: Grant
    Filed: June 11, 1982
    Date of Patent: February 7, 1984
    Assignee: Firma Carl Freudenberg
    Inventors: Jurgen Knoke, Holger Buchwald, Jurgen Fehlhaber
  • Patent number: 4203435
    Abstract: A wound dressing comprising at least five layers, the two outer layers comprising a permeable material non-adherent to a wound, below each outer layer there being arranged an absorbent layer each comprising cellulosic fibers, the absorbent layers being separated by a distribution layer comprising at least one of cellulose, carboxymethyl cellulose and a starch polymer. Advantageously the outer layers comprise a nonwoven fleece, a knit or woven fabric, or a perforated plastic sheet of at least one of polypropylene, polyethylene, polyesters, and polyamides, and the periphery of at least one of the outer layers carries a self-adhering adhesive inert to the skin. The entire structure is needled and, if fibrous, the outer layers are lightly thermally bonded so as to be fuzz-free.
    Type: Grant
    Filed: February 9, 1978
    Date of Patent: May 20, 1980
    Assignee: Firma Carl Freudenberg
    Inventors: Manfred Krull, Holger Buchwald, Wilhelm Kirsch
  • Patent number: 4113537
    Abstract: A high-temperature-resistant nonwoven fabric comprising synthetic fibers bonded to one another, said fibers comprising at least one polyaryl amide, polyaryl imide, polyaryl ester or polyaryl anhydride, said fibers being resistant to temperatures up to about 350.degree. C and being resistant to prolonged exposure to a temperature of at least 200.degree. C, is produced by bonding a suitable nonwoven web employing a solution containing a swelling agent and/or a bonding agent for the fiber. If a bonding agent is present, it is of substantially the same composition as the fiber and is precipitated or coagulated by treating the impregnated web with a liquid miscible with the solvent of the solution but which is a non-solvent for the bonding agent. The fabric is washed and dried and then preferably calendered at high temperature so that all the polymeric material is crystallized.
    Type: Grant
    Filed: December 3, 1975
    Date of Patent: September 12, 1978
    Assignee: Firma Carl Freudenberg
    Inventors: Werner Schafer, Holger Buchwald, Dieter Bischoff