Patents by Inventor Hans-Ludwig Schubert

Hans-Ludwig Schubert 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: 8758557
    Abstract: A process for producing fibrous material which includes the following: preparing a solution of chemicals that includes less than 25% of sulphite (calculated as Na2SO3), based on the oven-dry amount of the lignocellulosic raw material; mixing the solution of chemicals with wood in a specified liquor material; heating the solution of chemicals and the wood to a temperature above room temperature; and then either of the following alternatives: (1) removing the free-flowing solution of chemicals and digestion of the wood in the vapor phase; (2) having the wood digested in the liquid phase and separating the free-flowing solution of chemicals and the wood.
    Type: Grant
    Filed: April 4, 2007
    Date of Patent: June 24, 2014
    Assignee: Voith Patent GmbH
    Inventors: Esa-Matti Aalto, Hans-Ludwig Schubert
  • Patent number: 8152960
    Abstract: The invention relates to a wood-based lignocellulosic fibrous material having a tearing length of more than 8 km at 15° SR and a lignin content of at least 15%, based on the unbleached oven-dry fibrous material, for coniferous wood and having a tearing length of more than 5.0 km at 20° SR and a lignin content of at least 12%, based on the unbleached oven-dry fibrous material, for deciduous wood.
    Type: Grant
    Filed: April 4, 2007
    Date of Patent: April 10, 2012
    Assignee: Voith Patent GmbH
    Inventors: Hans-Ludwig Schubert, Esa-Matti Aalto, Rudolf Patt, Othar Kordsachia, Christoph Storz
  • Publication number: 20100032111
    Abstract: A process for producing fibrous material which includes the following: preparing a solution of chemicals that includes less than 25% of sulphite (calculated as Na2SO3), based on the oven-dry amount of the lignocellulosic raw material; mixing the solution of chemicals with wood in a specified liquor material; heating the solution of chemicals and the wood to a temperature above room temperature; and then either of the following alternatives: (1) removing the free-flowing solution of chemicals and digestion of the wood in the vapor phase; (2) having the wood digested in the liquid phase and separating the free-flowing solution of chemicals and the wood.
    Type: Application
    Filed: April 4, 2007
    Publication date: February 11, 2010
    Applicant: VOITH PATENT GmbH
    Inventors: Esa-Matti Aalto, Hans-Ludwig Schubert
  • Publication number: 20090314443
    Abstract: A method for producing fibrous material from softwood, hardwood, or annual plants, including preparing a solution of chemicals having one of: more than 5% of chemicals for softwood, more than 3.5% of chemicals for hardwood, or more than 2.5% of chemicals for annual plants. The method includes: mixing the solution of chemicals with the lignocellulosic material in a predetermined liquor ratio; heating the solution of chemicals and the lignocellulosic material to a temperature above room temperature; and, after the heating, performing one of: removing a free-flowing portion of the solution of chemicals and digesting the lignocellulosic material in a vapor phase, or digesting the lignocellulosic material in a liquid phase and separating the free-flowing portion of the solution of chemicals and the lignocellulosic material. The produced fibrous material has a lignin content of at least 15% for softwood, at least 12% for hardwood, and at least 10% for annual plants.
    Type: Application
    Filed: April 7, 2007
    Publication date: December 24, 2009
    Inventors: Esa-Matti Aalto, Hans-Ludwig Schubert
  • Publication number: 20090266500
    Abstract: The invention relates to a process for producing a tissue web, which is produced from a stock suspension including fibers. In this case, the volume and the tearing length are to be improved with the lowest possible freeness by the stock suspension containing lignocellolosic fibrous material made of wood or annual plants which has a tearing length of more than 6.5 km at 12°SR or a tearing length of more than 8.0 km at 15°SR and a lignin content of at least 15%, based on the oven-dry fibrous material, for coniferous wood in the unbleached state, or a tearing length of more than 4.5 km at 20°SR and a lignin content of at least 12%, based on the oven-dry fibrous material, for deciduous wood in the unbleached state, or a tearing length of more than 3.5 km at 20°SR and a lignin content of at least 10%, based on the oven-dry fibrous material, for annual plants in the unbleached state.
    Type: Application
    Filed: April 30, 2009
    Publication date: October 29, 2009
    Inventors: Hans-Ludwig Schubert, Frank Peter Meltzer, Esa-Matti Aalto
  • Publication number: 20090229774
    Abstract: The invention relates to a wood-based lignocellulosic fibrous material having a tearing length of more than 8 km at 15° SR and a lignin content of at least 15%, based on the unbleached oven-dry fibrous material, for coniferous wood and having a tearing length of more than 5.0 km at 20° SR and a lignin content of at least 12%, based on the unbleached oven-dry fibrous material, for deciduous wood.
    Type: Application
    Filed: April 7, 2007
    Publication date: September 17, 2009
    Inventors: Hans-Ludwig Schubert, Esa-Matti Aalto, Rudolf Patt, Othar Kordsachia, Christoph Storz
  • Patent number: 6432263
    Abstract: Process for increasing the water retaining ability of fibrous paper stocks. The process includes knead dispersing a fibrous paper stock having a stock concentration of at least about 20% and a temperature greater than about 45° C. A treatment for the knead dispersing is at least about 10 seconds. The process further includes completing a post-treatment phase to a machine tub of a paper machine in a reaction time of no longer than about 30 minutes.
    Type: Grant
    Filed: December 1, 2000
    Date of Patent: August 13, 2002
    Assignee: Voith Paper Patent GmbH
    Inventors: Volker Gehr, Almut Kriebel, Volker Niggl, Hans-Ludwig Schubert
  • Publication number: 20010002616
    Abstract: Process for increasing the water retaining ability of fibrous paper stocks. The process includes knead dispersing a fibrous paper stock having a stock concentration of at least about 20% and a temperature greater than about 45° C. A treatment for the knead dispersing is at least about 10 seconds. The process further includes completing a post-treatment phase to a machine tub of a paper machine in a reaction time of no longer than about 30 minutes.
    Type: Application
    Filed: December 1, 2000
    Publication date: June 7, 2001
    Applicant: Voith Paper Patent GmbH
    Inventors: Volker Gehr, Almut Kriebel, Volker Niggl, Hans-Ludwig Schubert