Patents by Inventor Helmut v. Freyhold

Helmut v. Freyhold 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).

  • Process for the manufacture of high purity silicic acid
    Patent number: 4264564
    Abstract: A process is herein described for the manufacture of high purity, granular silicic acid from aqueous alkali metal silicate solutions by acidification thereof, freezing and subsequently thawing the reaction mixture, and filtering, washing and drying the insoluble residue formed, in which the alkali metal silicate solutions have a molar ratio of SiO.sub.2 :Me.sub.2 O of from about 2:1 to 20:1, Me representing an alkali metal, and before freezing the aqueous alkali metal silicate solutions are adjusted to a pH value in the range of from about 2.5 to 6 and to a SiO.sub.2 content of from about 1 to 10 percent by weight by means of one or more aqueous solutions or suspensions of organic acids which complex aluminum, titanium, and iron ions and which form soluble alkali metal salts under the conditions of the process.
    Type: Grant
    Filed: August 30, 1979
    Date of Patent: April 28, 1981
    Assignee: Henkel Kommanditgesellschaft auf Aktien
    Inventors: Wolfgang Friedemann, Helmut V. Freyhold, Alfred Koster, Wolfgang Pesch
  • Binders based on alkali metal silicates and potassium metaborate
    Patent number: 4171986
    Abstract: Binders based on aqueous alkali metal silicate solution containing from 20% to 55% by weight of alkali metal silicates having a molar ratio SiO.sub.2 :M.sub.2 O of 1.8 to 4, and a content of potassium metaborate.
    Type: Grant
    Filed: March 24, 1978
    Date of Patent: October 23, 1979
    Assignee: Henkel Kommanditgesellschaft auf Aktien (Henkel KGaA)
    Inventors: Helmut v. Freyhold, Wolfgang Persh