Patents by Inventor Manilal Dahanayake

Manilal Dahanayake 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).

  • Publication number: 20060105919
    Abstract: A method of treating a subterranean formation by injecting down a well an aqueous fluid containing a viscoelastic surfactant fluid comprising an enhanced shear recovery agent wherein shear recovery time of the viscoelastic surfactant fluid is reduced by the addition of the enhanced shear recovery agent, and a viscoelastic surfactant fluid composition thereof.
    Type: Application
    Filed: November 14, 2005
    Publication date: May 18, 2006
    Inventors: Allwyn Colaco, Jean-Pierre Marchand, Fang Li, Manilal Dahanayake
  • Publication number: 20060019836
    Abstract: There is a viscoelastic fluid. The fluid has one or more cationic surfactants selected from the group consisting of certain quaternary salts, certain amines, and combinations thereof; one or more anionic polymers/anionic surfactants; one or more of certain zwitterionic/amphoteric surfactants; and water. There is also a method of fracturing a subterranean formation. The viscoelastic fluid is pumped through a wellbore and into a subterranean formation at a pressure sufficient to fracture the formation.
    Type: Application
    Filed: June 1, 2005
    Publication date: January 26, 2006
    Inventors: Fang Li, Manilal Dahanayake, Allwyn Colaco
  • Patent number: 5925714
    Abstract: Improved water soluble vinyl addition polymers for use as thickening and flocculating agents in water purification treatment, paper manufacture and waste water treatment are prepared using alkoxylated castor oil as an activation release agent. The release agent is biodegradable thereby making the overall product process more environmentally friendly.
    Type: Grant
    Filed: March 4, 1994
    Date of Patent: July 20, 1999
    Assignee: SNF S.A.
    Inventors: Eric H. Larson, Manilal Dahanayake, William R. Busler
  • Patent number: 5914310
    Abstract: According to the invention, an improved class of amphoteric surfactant having improved surfactant properties characterized as mild and environmentally safe has been provided comprising compounds of the formula: ##STR1## The amphoteric surfactant of the subject invention have at least two hydrophobic moieties and at least two hydrophilic groups per molecule and are useful as emulsifiers, detergents, dispersants and solubilizing agents.
    Type: Grant
    Filed: July 30, 1997
    Date of Patent: June 22, 1999
    Assignee: Rhodia Inc.
    Inventors: Ji Li, Manilal Dahanayake, Robert Lee Reierson, David James Tracy
  • Patent number: 5783554
    Abstract: According to the invention, an improved class of surfactants having improved surfactant properties characterized as mild and environmentally safe have been provided comprising compounds of the formula: ##STR1## The anionic surfactants of the invention have at least two hydrophobic chains and at least two hydrophilic groups per molecule and are useful as emulsifiers,detergents, dispersant and solubilizing agents.
    Type: Grant
    Filed: June 30, 1997
    Date of Patent: July 21, 1998
    Assignee: Rhodia Inc.
    Inventors: Ji Li, Manilal Dahanayake, Robert Lee Reierson, David James Tracy
  • Patent number: 5656586
    Abstract: According to the invention, an improved class of amphoteric surfactant having improved surfactant properties characterized as mild and environmentally safe has been provided comprising compounds of the formula: ##STR1## The amphoteric surfactant of the subject invention have at least two hydrophobic moieties and at least two hydrophilic groups per molecule and are useful as emulsifiers, detergents, dispersants and solubilizing agents.
    Type: Grant
    Filed: August 19, 1994
    Date of Patent: August 12, 1997
    Assignee: Rhone-Poulenc Inc.
    Inventors: Ji Li, Manilal Dahanayake, Robert Lee Reierson, David James Tracy
  • Patent number: 5643864
    Abstract: According to the invention, an improved class of anionic surfactants having improved surfactant properties characterized as mild and environmentally safe have been provided comprising compounds of the formula: ##STR1## The anionic surfactants of the invention have at least two hydrophobic chains and at least two hydrophilic groups per molecule and are useful as emulsifiers, detergents, dispersant and solubilizing agents.
    Type: Grant
    Filed: August 19, 1994
    Date of Patent: July 1, 1997
    Assignee: Rhone-Poulenc, Inc.
    Inventors: Ji Li, Manilal Dahanayake, Robert Lee Reierson, David James Tracy
  • Patent number: 5643498
    Abstract: According to the invention, an improved class of quaternary cationic surfactants having two imidazolinium groups have been provided comprising compounds of the formula: ##STR1## The surfactants of the subject invention have two hydrophobic moieties and two hydrophilic groups per molecule and are useful as hair and fabric conditioners as well as biocidal agents.
    Type: Grant
    Filed: August 19, 1994
    Date of Patent: July 1, 1997
    Assignee: Rhone-Poulenc Inc.
    Inventors: Ji Li, Manilal Dahanayake, Robert Lee Reierson, David James Tracy
  • Patent number: 5250499
    Abstract: An emulsifiable concentrate comprising an agriculturally active chemical, a surfactant, an organic diluent and a solvent having first and second components, the first component being capable of solubilizing the agriculturally active chemical and the second component in conjunction with the surfactant being effective to disperse the agriculturally active chemical. The inventive concentrate allows for high concentrations of the active ingredient, exhibits excellent stability and produces highly stable compositions upon dilution with water.
    Type: Grant
    Filed: October 31, 1990
    Date of Patent: October 5, 1993
    Assignee: ISP Investments Inc.
    Inventors: Kolazi S. Narayanan, Ratan K. Chaudhuri, Manilal Dahanayake
  • Patent number: 5176736
    Abstract: An emulsifiable concentrate comprising an agriculturally active chemical, a surfactant, an organic diluent and a solvent having first and second components, the first component being capable of solubilizing the agriculturally active chemical and the second component in conjunction with the surfactant being effective to disperse the agriculturally active chemical. The inventive concentrate allows for high concentrations of the active ingredient, exhibits excellent stability and produces highly stable compositions upon dilution with water.
    Type: Grant
    Filed: November 4, 1991
    Date of Patent: January 5, 1993
    Assignee: ISP Investments Inc.
    Inventors: Kolazi S. Narayanan, Ratan K. Chaudhuri, Manilal Dahanayake
  • Patent number: 5160528
    Abstract: An emulsifiable concentrate comprising an agriculturally active chemical, a surfactant, an organic diluent and a solvent having a component capable of solubilizing the agriculturally active chemical and, in conjunction with the surfactant, being effective to disperse the agriculturally active chemical. The inventive concentrate allows for high concentrations of the active ingredient, exhibits excellent stability and produces highly stable compositions upon dilution with water.
    Type: Grant
    Filed: April 5, 1990
    Date of Patent: November 3, 1992
    Assignee: ISP Investments Inc.
    Inventors: Ratan K. Chaudhuri, Kolazi S. Narayanan, Manilal Dahanayake
  • Patent number: 5156666
    Abstract: An emulsifiable concentrate comprising an agriculturally active chemical, a surfactant, and a solvent selected from the group consisting of a first component capable of solubilizing the agriculturally active chemical, a second component capable, in conjnction with the surfactant, to disperse the agriculturally active chemical, and combinations thereof, said first and second being biodegradeable. The inventive concentrate allows for high concentrations of the active ingredient, exhibits excellent stability and produces highly stable compositions upon dilution with water.
    Type: Grant
    Filed: June 28, 1990
    Date of Patent: October 20, 1992
    Assignee: ISP Investments Inc.
    Inventors: Kolazi S. Narayanan, Ratan K. Chaudhuri, Manilal Dahanayake
  • Patent number: 5071463
    Abstract: An emulsifiable concentrate comprising an agriculturally active chemical, a surfactant, an organic diluent and a solvent having first and second components, the first component being capable of solubilizing the agriculturally active chemical and the second component in conjunction with the surfactant being effective to disperse the agriculturally active chemical. The inventive concentrate allows for high concentrations of the active ingredient, exhibits excellent stability and produces highly stable compositions upon dilution with water.
    Type: Grant
    Filed: December 11, 1989
    Date of Patent: December 10, 1991
    Assignee: ISP Investments Inc.
    Inventors: Kolazi S. Narayanan, Ratan K. Chaudhuri, Manilal Dahanayake