Patents by Inventor Nayan H. Joshi

Nayan H. Joshi 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: 20190337022
    Abstract: To achieve efficient stripping of organic coatings from sensitive substrate without affecting the substrate surface, a novel non-aqueous stripping composition and method are provided. The stripping composition comprises: A. at least one high-boiling solvent selected from the group, consisting of alcohols having general chemical formula R—OH, wherein R is a C4-C30 hydrocarbon group, wherein the high-boiling solvent has a boiling point of at least 100° C.; B— at least one high-boiling co-solvent selected from the group, consisting of high-boiling glycols, glycol ethers and amine compounds, wherein the high-boiling co-solvent has a boiling point of at least 100° C.; and C— at least one pH-active agent either selected from the group, consisting of acid compounds or selected from the group, consisting of hydroxide compounds.
    Type: Application
    Filed: May 8, 2017
    Publication date: November 7, 2019
    Inventor: Nayan H. JOSHI
  • Patent number: 10456813
    Abstract: To achieve efficient stripping of organic coatings from sensitive substrate without affecting the substrate surface, a novel non-aqueous stripping composition and method are provided. The stripping composition comprises: A. at least one high-boiling solvent selected from the group, consisting of alcohols having general chemical formula R—OH, wherein R is a C4-C30 hydrocarbon group, wherein the high-boiling solvent has a boiling point of at least 100° C.; B—at least one high-boiling co-solvent selected from the group, consisting of high-boiling glycols, glycol ethers and amine compounds, wherein the high-boiling co-solvent has a boiling point of at least 100° C.; and C—at least one pH-active agent either selected from the group, consisting of acid compounds or selected from the group, consisting of hydroxide compounds.
    Type: Grant
    Filed: May 8, 2017
    Date of Patent: October 29, 2019
    Assignee: Atotech Deutschland GmbH
    Inventor: Nayan H. Joshi
  • Patent number: 9593247
    Abstract: The invention relates to a non-aqueous stripping composition for removing cured organic paint from substrates comprising i. a source of hydroxide ions; ii. a high-boiling alcohol having a boiling point of at least 100° C.; and iii. at least one surfactant represented by the following formula R—O—(CH2CH2O)nH and ?wherein R is an alkyl chain, linear or branched having a 2 to 24 carbon atom chain length.
    Type: Grant
    Filed: February 11, 2013
    Date of Patent: March 14, 2017
    Assignee: Atotech Deutschland GmbH
    Inventors: Nayan H. Joshi, Kerri Little Carver, Thomas Anthony Patena, Christopher George Ringholz
  • Publication number: 20140373878
    Abstract: The invention relates to a non-aqueous stripping composition for removing cured organic paint from substrates comprising i. a source of hydroxide ions; ii. a high-boiling alcohol having a boiling point of at least 100° C.; and iii. at least one surfactant represented by the following formula R—O—(CH2CH2O)nH and wherein R is an alkyl chain, linear or branched having a 2 to 24 carbon atom chain length.
    Type: Application
    Filed: February 11, 2013
    Publication date: December 25, 2014
    Applicant: Atotech Deutschland GmbH
    Inventors: Nayan H. Joshi, Kerri Little Carver, Thomas Anthony Patena, Christopher George Ringholz
  • Patent number: 8231743
    Abstract: Improved compositions and processes for zincating magnesium and magnesium alloy substrates. An aqueous zincating composition having a pH of from about 8 to about 11 and including zinc ions, a complexing agent, fluoride ions and a reducing agent. A non-electrolytic process for zincating a magnesium or magnesium alloy substrate, including immersing the substrate in the non-electrolytic aqueous zincating composition for a time sufficient to deposit a zincate on the substrate. A non-electrolytic process for zincating a magnesium or magnesium alloy substrate, including preparing a aqueous non-electrolytic composition comprising zinc ions, a complexing agent, fluoride ions and a pH in the range from about 8 to about 11; adding to the composition an amount of a reducing agent sufficient to improve deposition of zincate on the magnesium or magnesium alloy substrate; and immersing the substrate in a composition for a time sufficient to deposit the zincate on the substrate.
    Type: Grant
    Filed: October 22, 2009
    Date of Patent: July 31, 2012
    Assignee: Atotech Deutschland GmbH
    Inventors: Jacob Grant Wiles, Nayan H. Joshi
  • Publication number: 20110094631
    Abstract: Improved compositions and processes for zincating magnesium and magnesium alloy substrates. An aqueous zincating composition having a pH of from about 8 to about 11 and including zinc ions, a complexing agent, fluoride ions and a reducing agent. A non-electrolytic process for zincating a magnesium or magnesium alloy substrate, including immersing the substrate in the non-electrolytic aqueous zincating composition for a time sufficient to deposit a zincate on the substrate. A non-electrolytic process for zincating a magnesium or magnesium alloy substrate, including preparing a aqueous non-electrolytic composition comprising zinc ions, a complexing agent, fluoride ions and a pH in the range from about 8 to about 11; adding to the composition an amount of a reducing agent sufficient to improve deposition of zincate on the magnesium or magnesium alloy substrate; and immersing the substrate in a composition for a time sufficient to deposit the zincate on the substrate.
    Type: Application
    Filed: October 22, 2009
    Publication date: April 28, 2011
    Inventors: Jacob Grant Wiles, Nayan H. Joshi
  • Patent number: 7407689
    Abstract: The present invention provides a non-cyanide aqueous acidic immersion plating solution having a pH of from about 3.5 to about 6.5 and comprising zinc ions, nickel ions and/or cobalt iron ions, and fluoride ions. In one embodiment the immersion plating solutions of the invention also contain at least one inhibitor containing one or more nitrogen atoms, sulfur atoms, or both nitrogen and sulfur atoms. The present invention also relates to methods for depositing zinc alloy protective coatings on aluminum and aluminum alloy substrates comprising immersing the aluminum or aluminum alloy substrate in the non-cyanide acidic immersion plating solutions of the invention. Optionally, the zinc alloy coated aluminum or aluminum alloy substrate is plated using an electroless or electrolytic metal plating solution.
    Type: Grant
    Filed: June 26, 2003
    Date of Patent: August 5, 2008
    Assignee: Atotech Deutschland GmbH
    Inventors: Nayan H. Joshi, Maulik D. Mehta
  • Patent number: 7384901
    Abstract: A process for cleaning (e.g., desmutting) an aluminum surface, using compositions free of nitric acid and chromic acid and comprising, in one embodiment, an oxidant and at least one mineral acid salt. In another embodiment, the process uses a composition free of nitric acid and chromic acid and comprising an oxidant, at least one mineral acid salt, and a complexing agent which is a salt of an organic acid. Due at least in part to the absence of nitric and chromic acids, and in particular, strong mineral acids, the cleaning processes of the present invention remove smut residues from aluminum surfaces without significant etching of the aluminum.
    Type: Grant
    Filed: April 13, 2007
    Date of Patent: June 10, 2008
    Assignee: Atotech Deutschland GmbH
    Inventors: Nayan H. Joshi, Maulik D. Mehta
  • Publication number: 20040242449
    Abstract: Compositions useful particularly for cleaning (desmutting) an aluminum surface is described. The compositions are free of nitric acid and chromic acid, and comprise, in one embodiment, an oxidant and at least one mineral acid salt. In another embodiment, the composition is free of nitric acid and chromic acid, and the composition comprises an oxidant, at least one mineral acid salt, and a complexing agent which is a salt of an organic acid. Aqueous compositions free of nitric acid and chromic acid also are described. Due at least in part to the absence of nitric and chromic acids, and in particular, strong mineral acids, the cleaning compositions of the present invention remove smut residues from aluminum surfaces without significant etching of the aluminum.
    Type: Application
    Filed: June 2, 2003
    Publication date: December 2, 2004
    Inventors: Nayan H. Joshi, Maulik D. Mehta
  • Patent number: 6811819
    Abstract: The present invention relates to methods for depositing zincate coatings on aluminum and aluminum alloys comprising applying an immersion zincate coating on an aluminum or aluminum alloy substrates, optionally followed by plating the zincate coated aluminum or aluminum alloy substrate using an electroless or electrolytic metal plating solution. The present invention also relates to an improved aqueous alkaline zincate solution comprising hydroxide ions, zinc ions, nickel ions and/or cobalt iron ions, copper ions, and at least one inhibitor containing one or more nitrogen atoms, sulfur atoms, or both nitrogen and sulfur atoms provided said nitrogen atoms are not present in an aliphatic amine or hydroxylamine.
    Type: Grant
    Filed: March 23, 2004
    Date of Patent: November 2, 2004
    Assignee: Atotech Deutschland GmbH
    Inventors: Nayan H. Joshi, Maulik D. Mehta
  • Patent number: 6790265
    Abstract: The present invention provides an improved aqueous alkaline zincate solution comprising hydroxide ions, zinc ions, nickel ions and/or cobalt iron ions, copper ions, and at least one inhibitor containing one or more nitrogen atoms, sulfur atoms, or both nitrogen and sulfur atoms provided said nitrogen atoms are not present in an aliphatic amine or hydroxylamine. The present invention also relates to methods for depositing zincate coatings on aluminum and aluminum alloys comprising applying an immersion zincate coating on an aluminum or aluminum alloy substrates, optionally followed by plating the zincate coated aluminum or aluminum alloy substrate using an electroless or electrolytic metal plating solution.
    Type: Grant
    Filed: October 7, 2002
    Date of Patent: September 14, 2004
    Assignee: Atotech Deutschland GmbH
    Inventors: Nayan H. Joshi, Maulik D. Mehta
  • Publication number: 20040173467
    Abstract: The present invention relates to methods for depositing zincate coatings on aluminum and aluminum alloys comprising applying an immersion zincate coating on an aluminum or aluminum alloy substrates, optionally followed by plating the zincate coated aluminum or aluminum alloy substrate using an electroless or electrolytic metal plating solution. The present invention also relates to an improved aqueous alkaline zincate solution comprising hydroxide ions, zinc ions, nickel ions and/or cobalt iron ions, copper ions, and at least one inhibitor containing one or more nitrogen atoms, sulfur atoms, or both nitrogen and sulfur atoms provided said nitrogen atoms are not present in an aliphatic amine or hydroxylamine.
    Type: Application
    Filed: March 23, 2004
    Publication date: September 9, 2004
    Inventors: Nayan H. Joshi, Maulik D. Mehta
  • Publication number: 20040067314
    Abstract: The present invention provides an improved aqueous alkaline zincate solution comprising hydroxide ions, zinc ions, nickel ions and/or cobalt iron ions, copper ions, and at least one inhibitor containing one or more nitrogen atoms, sulfur atoms, or both nitrogen and sulfur atoms provided said nitrogen atoms are not present in an aliphatic amine or hydroxylamine. The present invention also relates to methods for depositing zincate coatings on aluminum and aluminum alloys comprising applying an immersion zincate coating on an aluminum or aluminum alloy substrates, optionally followed by plating the zincate coated aluminum or aluminum alloy substrate using an electroless or electrolytic metal plating solution.
    Type: Application
    Filed: October 7, 2002
    Publication date: April 8, 2004
    Inventors: Nayan H. Joshi, Maulik D. Mehta
  • Patent number: 6645557
    Abstract: A method of forming a conductive metal layer on a non-conductive surface, including providing a non-conductive surface; contacting the non-conductive surface with an aqueous solution or mixture containing a stannous salt to form a sensitized surface; contacting the sensitized surface with an aqueous solution or mixture containing a silver salt having a pH in the range from about 5 to about 10 to form a catalyzed surface; and electroless plating the catalyzed surface by applying an electroless plating solution to the catalyzed surface.
    Type: Grant
    Filed: October 17, 2001
    Date of Patent: November 11, 2003
    Assignee: Atotech Deutschland GmbH
    Inventor: Nayan H. Joshi
  • Publication number: 20030113452
    Abstract: A method of forming a conductive metal layer on a non-conductive surface, including providing a non-conductive surface; contacting the non-conductive surface with an aqueous solution or mixture containing a stannous salt to form a sensitized surface; contacting the sensitized surface with an aqueous solution or mixture containing a silver salt having a pH in the range from about 5 to about 10 to form a catalyzed surface; and electroless plating the catalyzed surface by applying an electroless plating solution to the catalyzed surface.
    Type: Application
    Filed: October 17, 2001
    Publication date: June 19, 2003
    Inventor: Nayan H. Joshi