Patents by Inventor John H. S. Rennie

John H. S. Rennie 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).

  • Patent number: 5112612
    Abstract: Porous spheroidal silica having a particle size in the range 1 to 400 microns, axial ratios of 1:1 to 1:12 has up to 50% by weight of the SiO.sub.2 of included material, such as for example perfumes, flavoring materials, pigments, germicides, bactericides, fungicides, bleaching agents, skin benefit agents, therapeutic agents, dispersed in the silica as particles or droplets in the size range 0.01 to 10 .mu.m. The spheroids can be made by mixing together an aqueous, stabilized silica sol containing dispersed therein up to 50% by weight of the silica of an included material and an aqueous solution of a non-adsorbing polymer to form a phase separated system comprising silica droplets containing included material in a polymer-rich continuous phase and condensing the silica sol to aggregate the droplets to form silica spheroids containing the dispersed included material. The included material can be released in use by e.g. wetting, attrition, dissolution, pH change, heating.
    Type: Grant
    Filed: May 23, 1990
    Date of Patent: May 12, 1992
    Assignee: Unilever Patent Holdings B.V.
    Inventors: Michael J. Garvey, Ian C. Griffiths, John H. S. Rennie
  • Patent number: 5011690
    Abstract: Porous spheroidal silica having a particle size in the range 1 to 400 microns, axial ratios of 1:1 to 1:12 has up to 50% by weight of the SiO.sub.2 of included material, such as for example perfumes, flavoring materials, pigments, germicides, bactericides, fungicides, bleaching agents, skin benefit agents, therapeutic agents, dispersed in the silica as particles or droplets in the size range 0.01 to 10 .mu.m. The spheroids can be made by mixing together an aqueous, stabilized silica sol containing dispersed therein up to 50% by weight of the silica of an included material and an aqueous solution of a non-adsorbing polymer to form a phase separated system comprising silica droplets containing included material in a polymer-rich continuous phase and condensing the silica sol to aggregate the droplets to form silica spheroids containing the dispersed included material. The included material can be released in use by e.g. wetting, attrition, dissolution, pH change, heating.
    Type: Grant
    Filed: June 6, 1988
    Date of Patent: April 30, 1991
    Assignee: Unilever Patent Holdings B.V.
    Inventors: Michael J. Garvey, Ian C. Griffiths, John H. S. Rennie