Patents by Inventor John H. C. Hung

John H. C. Hung 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).

  • Lavatory cleaning block
    Patent number: 5395546
    Abstract: A toilet cleaning block which releases a halogen disinfecting agent in a controlled, substantially constant rate for 2 to about 4 months of constant contact with water and is then completely dissolved in the water comprises an admixture of an agent which releases a halogen disinfecting agent when in contact with water, about 4 to 10% aluminum hydroxide based on the total weight of the block and up to about 1% by weight of a mold release lubricant, said admixture being in the form of a coherent solid resistant to internal water penetration having a density of 1.10 to 1.60 g/cc, a ratio of effective surface area to weight of about 1:1.05 to 1:1.25 and a crush fracturing strength of about 9-109 kg.
    Type: Grant
    Filed: October 19, 1992
    Date of Patent: March 7, 1995
    Assignee: Block Drug Company, Inc.
    Inventors: John H. C. Hung, Robert Carmello
  • Lavatory cleaning block comprising N,N-dichloro dialkyl hydantoin and aluminum hydroxide
    Patent number: 5178787
    Abstract: A toilet cleaning block which releases a halogen disinfecting agent in a controlled, substantially constant rate for 2 to about 4 months of constant contact with water and is then completely dissolved in the water comprises an admixture of an agent which releases a halogen disinfecting agent when in contact with water, about 4 to 10% aluminum hydroxide based on the total weight of the block and up to about 1% by weight of a mold release lubricant, said admixture being in the form of a coherent solid resistant to internal water penetration having a density of 1.10 to 1.60 g/cc, a ratio of effective surface area to weight of about 1:1.05 to 1:1.25 and a crush fracturing strength of about 9-109 kg.
    Type: Grant
    Filed: March 11, 1991
    Date of Patent: January 12, 1993
    Assignee: Block Drug Company, Inc.
    Inventors: John H. C. Hung, Robert Carmello