Patents by Inventor Kauko Nieminen

Kauko Nieminen 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 preparation of methylenebisphosphonic acids
    Patent number: 5237094
    Abstract: The present invention concerns a novel process for the preparation of methylenebisphosphonic acids of the formula I ##STR1## wherein Q.sup.1 and Q.sup.2 are independently hydrogen or halogen, by hydrolyzing the corresponding methylenebisphosphonic acid tetraester of the formula ##STR2## wherein R has the meaning of a straight or branched alkyl group containing 1 to 4 carbon atoms, and Q.sup.1 and Q.sup.2 have the same meaning as above.
    Type: Grant
    Filed: April 30, 1992
    Date of Patent: August 17, 1993
    Assignee: Leiras Oy
    Inventors: Klaus Lampi, Kauko Nieminen, Jarkko Ruohonen
  • Process for the purification of 2,6-diisopropyl phenol
    Patent number: 5175376
    Abstract: The object of the invention is a new method for the purification of 2,6-diisopropyl phenol (propofol). The invention is characterized in that the raw product obtained from the alkylation of propene with phenol is crystallized at a temperature where propofol crystallizes but the isomers and other phenol derivatives formed in the reaction are still in liquid form, i.e. at a temperature of -25.degree. to +18.degree. C. especially at -20.degree. to -10.degree. C., without a solvent or using a suitable solvent, such as hexane or petrol ether.
    Type: Grant
    Filed: April 30, 1992
    Date of Patent: December 29, 1992
    Assignee: Leiras Oy
    Inventors: Kauko Nieminen, Peter Essen