Patents by Inventor Jurgen Pitowski

Jurgen Pitowski 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: 6159601
    Abstract: Cellulosic fibers made from a solution of cellulose in a tertiary amine oxide and optionally water and which have a low tendency to fibrillate are produced by coagulating the fibers in at least two stages. The residence time of the fibers in the first coagulation stage is adjusted so that on leaving the first coagulation stage only the adhesiveness of the surface of the solution formed into fibers has been counteracted. In subsequent coagulation stages, the fibers are kept in a slack state. On leaving the final coagulation stage, the fibers have been thoroughly coagulated. The cellulosic fibers have a new structure and apart from a very low tendency to fibrillate, they possess a high dyeing level.
    Type: Grant
    Filed: February 2, 1999
    Date of Patent: December 12, 2000
    Assignee: Akzo Nobel NV
    Inventors: Hans-Jurgen Pitowski, Ulrich Wigand Wachsmann
  • Patent number: 6042944
    Abstract: Process for manufacturing cellulose formed objects, whereby a solution of cellulose is formed in the warm state in a tertiary amine N-oxide and, if necessary, water and the formed solution is cooled with air before introducing it into a coagulation bath. Conditioned air is employed for cooling which exhibits a water content of 0.1 to 7 g water vapor per kg dry air and whose relative humidity amounts to less than 85%.
    Type: Grant
    Filed: December 18, 1998
    Date of Patent: March 28, 2000
    Assignee: Akzo Nobel NV
    Inventor: Jurgen Pitowski
  • Patent number: 5958320
    Abstract: Cellulosic fibers made from a solution of cellulose in a tertiary amine oxide and optionally water and which have a low tendency to fibrillate are produced by coagulating the fibers in at least two stages. The residence time of the fibers in the first coagulation stage is adjusted so that on leaving the first coagulation stage only the adhesiveness of the surface of the solution formed into fibers has been counteracted. In subsequent coagulation stages, the fibers are kept in a slack state. On leaving the final coagulation stage, the fibers have been thoroughly coagulated. The cellulosic fibers have a new structure and apart from a very low tendency to fibrillate, they possess a high dyeing level.
    Type: Grant
    Filed: January 7, 1998
    Date of Patent: September 28, 1999
    Assignee: Akzo Nobel NV
    Inventors: Hans-Jurgen Pitowski, Ulrich Wigand Wachsmann
  • Patent number: 5902532
    Abstract: Process for manufacturing cellulose formed objects, whereby a solution of cellulose is formed in the warm state in a tertiary amine N-oxide and, if necessary, water and the formed solution is cooled with air before introducing it into a coagulation bath. Conditioned air is employed for cooling which exhibits a water content of 0.1 to 7 g water vapor per kg dry air and whose relative humidity amounts to less than 85%.
    Type: Grant
    Filed: June 3, 1997
    Date of Patent: May 11, 1999
    Assignee: Akzo Nobel NV
    Inventor: Jurgen Pitowski
  • Patent number: 4686044
    Abstract: A method is provided for producing a membrane from polycarbonate-polyether-blockcopolymers with about 5 to 35 weight percent of repeating alkyleneethercarbonate units and about 95 to 65 weight percent of repeating bisphenol A-carbonate units, wherein the polyethyleneoxide blocks have a molecular weight from about 1,000 to 20,000, wherein the intrinsic viscosity of the copolymer is from about 180 to 300 ml/g as measured in chloroform at 25.degree. C. and wherein the ultrafiltration rate is from about 4 to 200 ml/h.m.sup.2.mm Hg. In a first dissolving step a polycarbonate-polyether-copolymer is homogeneously mixed with a solvent at a temperature from about 80.degree. to 120.degree. C. and in a second dissolving step the temperature is brought to about 140.degree. to 180.degree. C. to produce a true solution. The filtered solution is cooled to from about 20.degree. to 50.degree. C. and is then extruded through a nozzle into a bath comprising a nonsolvent for the polymer for precipitating the polymer.
    Type: Grant
    Filed: December 9, 1985
    Date of Patent: August 11, 1987
    Assignee: AKZO NV
    Inventors: Joachim Behnke, Hans-Jurgen Pitowski
  • Patent number: 4612688
    Abstract: Staple fibers made from crimped, in particular compression crimped, multicomponent filaments of the matrix/segment type, the cross section of which shows, in addition to the matrix, at least 6 peripheral wedge-shaped or lenticular segments, not completely covered by the matrix, are processed into a web, which is then mechanically bonded, preferably by needling. Subsequently, the fabric is subjected to a shrinkage process, by which its density is increased by more than 30%, themulticomponent fibers being completely or partly split up into their components. The difference in shrinkage between the components should be at least 10%. The liquids used for the shrinkage treatment are in particular organic liquids, such as methylene chloride, as well as other liquids producing a difference in shrinkage of at least 20%.
    Type: Grant
    Filed: March 21, 1985
    Date of Patent: September 23, 1986
    Assignee: Akzona Incorporated
    Inventors: Klaus Gerlach, Nikolaus Mathes, Hans-Jurgen Pitowski, Friedbert Wechs
  • Patent number: 4342801
    Abstract: Staple fibers made from crimped, in particular compression crimped, multicomponent filaments of the matrix/segment type, the cross section of which shows, in addition to the matrix, at least 6 peripheral wedge-shaped or lenticular segments, not completely covered by the matrix, are processed into a web, which is then mechanically bonded, preferably by needling. Subsequently, the fabric is subjected to a shrinkage process, by which its density is increased by more than 30%, the multicomponent fibers being completely or partly split up into their components. The difference in shrinkage between the components should be at least 10%. The liquids used for the shrinkage treatment are in particular organic liquids, such as methylene chloride, as well as other liquids producing a difference in shrinkage of at least 20%.
    Type: Grant
    Filed: December 16, 1980
    Date of Patent: August 3, 1982
    Assignee: Akzona Incorporated
    Inventors: Klaus Gerlach, Nikolaus Mathes, Hans-Jurgen Pitowski, Friedbert Wechs
  • Patent number: 3974320
    Abstract: A synthetic leather consisting essentially of three adherent microporous polyurethane layers, including a first base layer of a polyurethane impregnated fibrous fleece or web, a second or intermediate polyurethane layer containing 3-30% by weight of very finely divided insoluble solid particles with an individual volume is less than 2.times.10.sup..sup.-2 mm..sup.3 and with a maximum length generally below about 0.3 mm., preferably less than 0.1 mm., and a third or cover polyurethane layer which can be finished in a conventional manner. The product is especially distinguished by a smooth and uniform surface resistant to the "orange peel" effect. The method is distinguished by the application of the intermediate layer before the base layer is completely coagulated or solidified in the formation of the microporous structure.
    Type: Grant
    Filed: August 6, 1973
    Date of Patent: August 10, 1976
    Assignee: Akzo N.V. of Arnhem, Holland
    Inventors: Klaus Gerlach, Hans Jurgen Pitowski, Klaus Schneider