Patents by Inventor Tiang-Shing Chang

Tiang-Shing Chang 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: 5753723
    Abstract: An improved denture fixative composition comprising an adhesion promoter and a highly cross-linked copolymer of a lower alkyl vinyl ether and maleic anhydride or acid is disclosed wherein at least 65.0% of the total number of initial carboxyl groups in the copolymer are reacted. The cross-linking agent employed in this invention is calcium cation and optionally up to about 30.0% of the calcium function can be replaced with other inorganic cross-linking agents or polyhydroxy compounds either singly or in combination. The adhesion promoters are chelating agents such as polycarboxylic acids, hydroxycarboxylic acids, aminocarboxylic acids, polyphosphoric acids and their alkali salts.
    Type: Grant
    Filed: July 25, 1997
    Date of Patent: May 19, 1998
    Inventors: Tiang Shing Chang, Donna Diferdinando
  • Patent number: 5750591
    Abstract: A denture adhesive with significantly improved hold performance is comprised of the mixed partial salts of polymethyl vinyl ether maleic acid. At least one of said salts comprises zirconium while a second salt is selected from the group consisting of calcium, zinc, magnesium, iron, strontium and mixtures thereof. Optionally, a tripartite salt formulation may be prepared utilizing sodium, lithium or potassium. The adhesives are formulated in a standard pharmaceutically acceptable vehicle comprised of waxes, oils, colorants, viscosity modifiers and the like as is known in the art. The denture adhesive may be formulated as a paste, powder or liquid which has rapid absorption characteristics for faster swelling softening and superior coalescence.
    Type: Grant
    Filed: March 3, 1997
    Date of Patent: May 12, 1998
    Assignee: The Block Drug Company
    Inventors: Hal C. Clarke, Hyung-Kook Ahn, Eddie Wong, Robert C. Gasman, Alfred J. Smetana, Joseph Synodis, Tiang Shing Chang
  • Patent number: 5696181
    Abstract: An improved denture adhesive composition is comprised of a highly cross-linked lower alkyl ether/maleic acid or maleic anhydride copolymer in which up to about 85% of the initial free carboxyl groups are reacted with one or more cross-linking agents. The cross-linking agents are mixtures of inorganic divalent cations such as calcium, magnesium and zinc together with organic bifunctional compounds comprised of polyhydroxyl compounds such as propylene glycol, glycerin and the like. The copolymer has a specific viscosity of no less than 1.5. A hydrophilic polymer such as sodium alginate or carboxymethyl cellulose may also be added to the lower alkyl vinyl ether/maleic acid or maleic anhydride copolymer which is then formulated with other excipients in a paste, powder, liquid, gel or cream composition.
    Type: Grant
    Filed: September 22, 1995
    Date of Patent: December 9, 1997
    Assignee: The Block Drug Company, Inc.
    Inventors: Tiang-Shing Chang, Donna DiFerdinando
  • Patent number: 5188755
    Abstract: A surface erodible controlled releasing, free standing cleaning block for domestic water closets comprises controlled releasing agent, erosion rate modifier, processing aid, acidic chelating agent, color indicator, density modifier and internal lubricant.
    Type: Grant
    Filed: October 10, 1991
    Date of Patent: February 23, 1993
    Assignee: Block Drug Company
    Inventor: Tiang-Shing Chang
  • Patent number: 5120528
    Abstract: This invention relates to a mild oral hygiene composition such as a toothpaste, dental gel, mouthrinse or tooth powder containing a mild surfactant, protein fatty acid condensate or acid hydrolyzed, hydrolyzed animal protein or the mixtures thereof, and in combination therewith, mild high foaming surfactant, e.g., disodium cocoamido MIPA sulfosuccinate or disodium oleamido PEG-2 sulfosuccinate or disodium lauryl sulfosuccinate or the mixtures thereof; or a natural emulsifier, e.g., lecithin, or both a mild surfactant and a nautral emulsifier.
    Type: Grant
    Filed: June 12, 1991
    Date of Patent: June 9, 1992
    Assignee: Block Drug Company, Inc.
    Inventors: Tiang-shing Chang, Joseph Kanapka, Michael C. Alfano
  • Patent number: 4986754
    Abstract: A nonshrinkable, thermoplastic and injectable endodontic filling composition. The composition is a mixture of transpolyisoprene, either naturally produced as balata or gutta percha, or synthesized from isoprene, and a liquid castor ester platicizer. Alternatively, the mixture comprises transpolyisoprene, a liquid castor ester plasticizer and a liquid castor oil or dimethyl silcon fluid lubricant. The mixture is preferably a combination of the transpolyisoprene, the liquid castor ester plasticizer and the liquid castor oil or liquid dimethyl silicon fluid lubricant or both. The composition is compounded to form a highly thermoplastic material which is injectable at a clinically acceptable temperature with a manually operated injection system without shrinkage of the composition after placement in a dental root canal.
    Type: Grant
    Filed: July 2, 1990
    Date of Patent: January 22, 1991
    Assignee: Block Drug Co., Inc.
    Inventors: Tiang-shing Chang, Lisa N. W. Marchese
  • Patent number: 4950697
    Abstract: A nonshrinkable, thermoplastic and injectable endodontic filling composition. The composition is a mixture of transpolyisoprene, either naturally produced as balata or gutta percha, or synthesized from isoprene, and a liquid castor ester platicizer. Alternatively, the mixture comprises transpolyisoprene, a liquid castor ester platicizer and castor oil or dimethyl silicon fluid lubricant. The mixture is preferably a combination of the transpolyisoprene, the liquid castor ester plasticizer and the liquid castor oil or dimethyl silicon fluid lubricant or both. The composition is compounded to form a highly thermoplastic material which is injectable at a clinically acceptable temperature with a manually operated injection system without shrinkage of the composition after placement in a dental root canal.
    Type: Grant
    Filed: September 15, 1988
    Date of Patent: August 21, 1990
    Assignee: Block Drug Co., Inc.
    Inventors: Tiang-shing Chang, Lisa N. Weddle Marchese
  • Patent number: 4544356
    Abstract: A dental prophylactic device has a handle section containing a drive member and a driven section at a substantial angle to the handle section containing a driven member also at an angle to the driving member. The handle section includes a longitudinally oscillatable cam follower supported parallel to the handle axis. When the cam follower is translated around the axis by the rotation of the drive shaft, it is caused to oscillate by one end contacting the stationary cam follower track. The other end engages a slot parallel to the axis of a cam at an angle to the cam follower thereby causing the cam to oscillate back and forth over an arc of at least 50.degree. to approximately 150.degree., maintaining the connection between the cam follower and the cam by the use of the slot which permits the cam follower, in effect, to move up and down with respect to the cam as it oscillates.
    Type: Grant
    Filed: November 15, 1984
    Date of Patent: October 1, 1985
    Assignee: Block Drug Company Inc.
    Inventors: John M. Gardella, Casimir Ciepierski, Michael Alfano, Tiang-Shing Chang
  • Patent number: 4542168
    Abstract: A denture fixative composition contains as the active fixative a partially neutralized and crosslinked polyacrylic acid or a precursor combination of the polyacrylic acid, neutralizing agent(s) and crosslinking agent(s) which is adapted to form the active fixative, and at least one hydrophilic polymer, preferably, sodium carboxymethyl cellulose, hydroxypropyl guar or sodium alginate.
    Type: Grant
    Filed: February 6, 1984
    Date of Patent: September 17, 1985
    Assignee: Block Drug Co., Inc.
    Inventors: Tiang-Shing Chang, Lucy J. Zientek, Arthur Viningauz
  • Patent number: 4521551
    Abstract: Denture fixative compositions contain denture fixative excipients and as the denture fixative, a water soluble partially neutralized alkyl vinyl ether-maleic acid or anhydride copolymer, optionally partly crosslinked, and at least one hydrophilic polymer, preferably sodium carboxymethylcellulose, polyethylene oxide or hydroxypropyl guar.
    Type: Grant
    Filed: December 2, 1983
    Date of Patent: June 4, 1985
    Assignee: Block Drug Company, Inc.
    Inventors: Tiang-Shing Chang, Lucy J. Zientek
  • Patent number: 4470814
    Abstract: A method for adhering dentures to oral mucosa with a denture fixative composition containing as the active fixative a partially neutralized and crosslinked polyacrylic acid or a precursor combination of the polyacrylic acid, neutralizing agent(s) and crosslinking agent(s) which is adapted to form the active fixative, and at least one hydrophilic polymer, preferably, sodium carboxymethyl cellulose, hydroxypropyl guar or sodium alginate.
    Type: Grant
    Filed: September 2, 1983
    Date of Patent: September 11, 1984
    Assignee: Block Drug Company, Inc.
    Inventors: Tiang-Shing Chang, Lucy J. Zientek, Arthur Viningauz
  • Patent number: 4373036
    Abstract: A denture fixative composition contains a dentally acceptable excipient and an effective fixative amount of a fixative mixture comprising hydroxypropyl cellulose and at least one partially neutralized alkyl vinyl ether-maleic acid or anhydride copolymer, optionally partly crosslinked, or a partially neutralized, optionally partly crosslinked polyacrylic acid or a precursor combination of the copolymer or polyacrylic acid, neutralizing agents, and optionally crosslinking agents, which is adapted to form the fixative in situ, or polyethylene oxide.
    Type: Grant
    Filed: December 21, 1981
    Date of Patent: February 8, 1983
    Assignee: Block Drug Company, Inc.
    Inventors: Tiang-Shing Chang, Lucy J. Zientek, Arthur Viningauz, Marcy L. Scheps
  • Patent number: 4310516
    Abstract: An anhydrous pseudoplastic and thixotropic oleaginous vehicle is prepared by mixing at least one solid emulsifying agent having an HLB number of 12 or less with an oleaginous material and then cooling the mixture over a temperature range of at least about 15.degree. C., said range encompassing the pour point of said agent.
    Type: Grant
    Filed: February 1, 1980
    Date of Patent: January 12, 1982
    Assignee: Block Drug Company Inc.
    Inventors: Tiang-Shing Chang, Lucy J. Zientek