Patents by Inventor Helmut Krol

Helmut Krol 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).

  • Production of bitumen compositions containing ethylene-.alpha.-olefin rubber
    Patent number: 3963659
    Abstract: Homogeneous thermoplastic bituminous compositions containing up to 25 parts by weight of ethylene-.alpha.-olefin rubber, e.g. ethylene-propylene rubber, saturated or unsaturated, exhibit improved properties for all asphalt applications, e.g. pipe coating, roads, roofing, etc. The compositions are produced by heating and agitating the bitumen and rubber at above 170.degree. C., preferably 180.degree.-240.degree. C., or by subjecting the rubber to premastication before admixture with the bitumen at lower temperatures. Cross-linkable rubbers can be cross-linked in the bituminous compositions to yield high tensile strength final products.
    Type: Grant
    Filed: April 25, 1975
    Date of Patent: June 15, 1976
    Assignee: Chemische Werke Huls Aktiengesellschaft
    Inventors: Gerhard Binder, Harald Blumel, Helmut Krol