Patents Assigned to MBT Schweiz AG
  • Preparation of concrete accelerator
    Patent number: 6692564
    Abstract: An alkali-free accelerator for sprayed concrete is prepared by dissolving aluminium sulphate and amorphous aluminium hydroxide in water which optionally contains one amine, and optionally adding at least one stabiliser, selected from hydroxycarboxylic acid and phosphoric acids and non-alkaline salts thereof, and at least one defoaming agent.
    Type: Grant
    Filed: June 6, 2002
    Date of Patent: February 17, 2004
    Assignee: MBT (Schweiz) AG
    Inventor: Thomas Hofmann
  • Cement structure containing a waterproofing layer
    Patent number: 6489032
    Abstract: A process of providing a waterproof concrete structure comprising the steps of (a) providing a layer of a concrete composition on a support; (b) spraying on to this concrete composition a waterproofing layer; and (c) applying to the waterproofing layer a further layer of a concrete composition; characterized in that the waterproofing layer is provided by a composition which comprises an aqueous dispersion of coalescable particles of thermoplastic polymer. The method is useful in the waterproofing of tunnel linings.
    Type: Grant
    Filed: January 5, 1999
    Date of Patent: December 3, 2002
    Assignee: MBT Schweiz AG
    Inventors: Karoly Dischö, Max Oppliger