Patents by Inventor Ariello R. Corradi

Ariello R. Corradi 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 magnetic powders based on .gamma.-Fe.sub.2 O.sub.3
    Patent number: 4224175
    Abstract: A process is disclosed for obtaining acicular magnetic particles of .gamma.-Fe.sub.2 O.sub.3 modified with Fe.sup.++ and Co.sup.++ ions. The product thus obtained and magnetic tapes containing said product are also disclosed. A suspension of acicular .gamma.-Fe.sub.2 O.sub.3 in an aqueous solution of soluble Fe.sup.++ and Co.sup.++ salts is prepared. NH.sub.3 is then added in such quantity that the molar ratioNH.sub.3 /(Fe.sup.++ +Co.sup.++)is between 2.1 and 3, and the whole mass is then heated up to 100.degree.-200.degree. C. When the molar ratio Fe.sup.++ /Co.sup.++ is greater than about 2.5, it is necessary to operate in the presence of a metered quantity of oxygen or of an oxygen-containing gas; when the ratio is smaller or equal to about 2.5, the presence of a metered quantity of oxygen is optional.
    Type: Grant
    Filed: April 13, 1979
    Date of Patent: September 23, 1980
    Assignee: Montedison S.p.A.
    Inventors: Franco Montino, Ariello R. Corradi, Erminio Nonato