Patents by Inventor Dilip K. Ray-Chaudhuri

Dilip K. Ray-Chaudhuri 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: 5626840
    Abstract: A polyurethane, soluble or dispersible in water, prepared from an organic diisocyante, a diol, and a 2,2-hydroxymethyl-substituted carboxylic acid is neutralized with a cosmetically acceptable organic or inorganic base and formulated into a hair fixative composition containing low amounts of volatile organic solvent.
    Type: Grant
    Filed: November 30, 1995
    Date of Patent: May 6, 1997
    Assignee: National Starch and Chemical Investment Holding Corporation
    Inventors: John Thomaides, Julie V. Russo, Gary T. Martino, Dilip K. Ray-Chaudhuri
  • Patent number: 5455369
    Abstract: A process for preparing methyl .alpha.-cyanoacrylate in which methyl cyanoacetate is reacted with formaldehyde to form a polymer, which is subsequently depolymerized to the monomeric product, comprises using an ester of poly(ethylene glycol) as the solvent for the polymerization and depolymerization reactions.
    Type: Grant
    Filed: December 2, 1994
    Date of Patent: October 3, 1995
    Assignee: National Starch and Chemical Investment Holding Corporation
    Inventors: Eric A. Meier, Dilip K. Ray-Chaudhuri, Jules E. Schoenberg
  • Patent number: 5310835
    Abstract: In a two-part adhesive composition wherein one-part comprises a polymerizable acrylic monomer and an organoboron amine complex and the second-part contains an organic acid destabilizer and optional acrylic polymer, the improvement wherein a transparent or clear bond is provided in the cured adhesive composition by having about 45% or more by weight of the total acrylic monomer in the composition comprising selected phenyl containing acrylic compounds.
    Type: Grant
    Filed: September 30, 1993
    Date of Patent: May 10, 1994
    Assignee: National Starch and Chemical Investment Holding Corporation
    Inventors: Martin M. Skoultchi, Dilip K. Ray-Chaudhuri
  • Patent number: 4770668
    Abstract: This invention provides novel adducts of cyclic ethylene urea which are useful as permanent press agents. These adducts include acid, polyacid, ester, and multiester derivatives of cyclic ethylene urea and can be produced by the reaction of the cyclic ethylene urea with glyoxylic acid and glyoxylic acid derivatives, specifically ester acetals of glyoxylic acid. Such materials impart a high degree of permanent press properties to cellulose and cellulose/polymer blend fabrics.
    Type: Grant
    Filed: January 19, 1988
    Date of Patent: September 13, 1988
    Assignee: National Starch and Chemical Corporation
    Inventors: Martin Skoultchi, Dilip K. Ray-Chaudhuri
  • Patent number: 4690996
    Abstract: Polysaccharide graft copolymers are prepared by a water-in-oil emulsion polymerization process in which the polysaccharide and water-soluble monomer are emulsified in an oil phase containing emulsifying agents and polymerized therein. The resultant emulsion polymers are in stable form and may be used directly, for example, as adhesives for prepasted wallpaper, or may be inverted into aqueous systems and used for their thickening or flocculating properties.
    Type: Grant
    Filed: August 28, 1985
    Date of Patent: September 1, 1987
    Assignee: National Starch and Chemical Corporation
    Inventors: Yen-Jer Shih, John (Ji-Hsiung) Tsai, Wen B. Chiao, Dilip K. Ray-Chaudhuri
  • Patent number: 4663075
    Abstract: Novel gelling agents are prepared by reacting diphenyldiisocyanates with sulfur trioxide in a molar concentration of about 1:2. When the sulfonated diphenyldiisocyanate is added to water in concentrations above 2%, a gel is produced which is stable under acidic conditions at pH levels of about 4 or less.
    Type: Grant
    Filed: December 4, 1985
    Date of Patent: May 5, 1987
    Assignee: National Starch and Chemical Corporation
    Inventors: Wen B. Chiao, Dilip K. Ray-Chaudhuri
  • Patent number: 4644040
    Abstract: Novel acrylic adhesive compositions are prepared comprising an acrylic or substituted acrylic monomer and a normal poyimide or polyisomide bis-acetylene additive.
    Type: Grant
    Filed: April 3, 1986
    Date of Patent: February 17, 1987
    Assignee: National Starch and Chemical Corporation
    Inventors: Robert D. Rossi, Dilip K. Ray-Chaudhuri
  • Patent number: 4588767
    Abstract: A hot-melt adhesive especially useful in the construction of disposable diapers contains a vinyl polymer of 40-90% by weight of a C.sub.1 -C.sub.12 alkyl acrylate and 10-60% by weight of an alpha-olefin of C.sub.20 -C.sub.40, wherein the alkyl acrylate may be partially replaced with vinyl acetate or with a C.sub.6 -C.sub.12 olefin or with mixtures thereof, provided that the polymer contain at least 10% by weight of the alkyl acrylate. The adhesive may also contain a tackifying resin, a wax, an oil or a stabilizer depending on the specific end-use desired. In a preferred embodiment the polymer contains 20-45% by weight of the alpha-olefin.
    Type: Grant
    Filed: May 24, 1985
    Date of Patent: May 13, 1986
    Assignee: National Starch and Chemical Corporation
    Inventors: Jules E. Schoenberg, Thomas P. Flanagan, Dilip K. Ray-Chaudhuri
  • Patent number: 4581461
    Abstract: Maleated aminophenoxysiloxanes are prepared by reacting diaminodiphenoxysiloxanes with maleic anhydride. In addition, the resultant maleamic acid derivatives may be cyclized yielding isomaleimide or maleimide siloxane derivatives.
    Type: Grant
    Filed: April 7, 1983
    Date of Patent: April 8, 1986
    Assignee: National Starch and Chemical Corporation
    Inventors: Robert D. Rossi, Dilip K. Ray-Chaudhuri
  • Patent number: 4578444
    Abstract: Novel anaerobic curing compositions prepared containing polymerizable (meth)acrylate monomers, free radical initiators and, as a polymerizable activators therefor, monomeric disulfonimides.
    Type: Grant
    Filed: October 1, 1984
    Date of Patent: March 25, 1986
    Assignee: National Starch and Chemical Corporation
    Inventors: Robert D. Rossi, Dilip K. Ray-Chaudhuri
  • Patent number: 4535140
    Abstract: A hot-melt adhesive especially useful in the construction of disposable diapers contains a vinyl polymer of 40-90% by weight of a C.sub.1 -C.sub.12 alkyl acrylate and 10-60% by weight of an alpha-olefin of C.sub.20 -C.sub.40, wherein the alkyl acrylate may be partially replaced with vinyl acetate or with a C.sub.6 -C.sub.12 olefin or with mixtures thereof, provided that the polymer contain at least 10% by weight of the alkyl acrylate. The adhesive may also contain a tackifying resin, a wax, an oil or a stabilizer depending on the specific end-use desired. In a preferred embodiment the polymer contains 20-45% by weight of the alpha-olefin.
    Type: Grant
    Filed: July 17, 1981
    Date of Patent: August 13, 1985
    Assignee: National Starch and Chemical Corporation
    Inventors: Jules E. Schoenberg, Thomas P. Flanagan, Dilip K. Ray-Chaudhuri
  • Patent number: 4532270
    Abstract: Novel curing compositions are prepared comprising an acrylic or substituted acrylic monomer and a normal polyimide or polyisoimide bis-acetylene additive.
    Type: Grant
    Filed: January 27, 1984
    Date of Patent: July 30, 1985
    Assignee: National Starch and Chemical Corporation
    Inventors: Robert D. Rossi, Dilip K. Ray-Chaudhuri
  • Patent number: 4510324
    Abstract: The invention provides disulfonimide compounds of the general formula ##STR1## wherein X is bromine, chlorine or iodine; R is hydrogen or methyl; and R' is alkyl, aryl or substituted aryl. The compounds are useful as activators for anaerobic adhesive compositions and also as intermediates in the preparation of monomers of the general formula ##STR2## wherein R and R' are as defined above. The monomers are polymerizable to form homo- and copolymers useful in the photographic industry as well as in formulating anaerobic adhesive compositions.
    Type: Grant
    Filed: April 28, 1983
    Date of Patent: April 9, 1985
    Assignee: National Starch and Chemical Corp.
    Inventors: Robert D. Rossi, Dilip K. Ray-Chaudhuri
  • Patent number: 4450261
    Abstract: Styrene and maleic anhydride monomers are copolymerized in 1,2-dichloroethane employing 3-mercaptopropionic acid or methyl-3-mercaptopropionate chain transfer agents producing an odorless copolymer in the molecular weight range of about 500 to 10,000 which remains soluble in the solvent. The resultant copolymer may be conveniently sulfonated in the 1,2-dichloroethane solvent used for the polymerization thereby producing an odorless sulfonated copolymer.
    Type: Grant
    Filed: February 22, 1983
    Date of Patent: May 22, 1984
    Assignee: National Starch and Chemical Corporation
    Inventors: Wen B. Chiao, Dilip K. Ray-Chaudhuri
  • Patent number: 4448935
    Abstract: Polystyrene and styrene copolymers are simultaneously crosslinked and sulfonated in a homogeneous reaction mixture by incorporation of from 0.1 to 5 mole percent of specific crosslinking reagents in the polymer sulfonating solution. The crosslinking reagents are selected aryl compounds having at least two --CH.sub.2 X radicals where X is hydroxyl, chlorine or bromine.
    Type: Grant
    Filed: July 21, 1982
    Date of Patent: May 15, 1984
    Assignee: National Starch and Chemical Corporation
    Inventors: Carmine P. Iovine, Dilip K. Ray-Chaudhuri
  • Patent number: 4401793
    Abstract: Novel stable anaerobic compositions are prepared which contain, as a novel reactive thickener, a polymerizable polymeric adduct having pendant double bonds which is dissolved in a polymerizable monomeric diluent. The anaerobic compositions show improved performance properties. The thickener is prepared by reacting an anhydride-containing polymer with an excess of a C.sub.2 -C.sub.5 hydroxyalkyl acrylate or methacrylate (e.g. hydroxyethyl and hydroxypropyl methacrylate), optionally in the presence of (meth)acrylate monomers which are not reactive with the anhydride groups of the polymer and which act as an additional diluent. The polymer may be prepared by conventional free radical polymerization techniques using maleic, citraconic, and/or itaconic anhydride and an ethylenically unsaturated monomer (e.g. C.sub.1 -C.sub.10 alkyl acrylates or methacrylates or styrene).
    Type: Grant
    Filed: September 4, 1981
    Date of Patent: August 30, 1983
    Assignee: National Starch And Chemical Corporation
    Inventors: Wen B. Chiao, Dilip K. Ray-Chaudhuri
  • Patent number: 4305860
    Abstract: Stable, pumpable, solvent-free polyampholyte latices characterized by their colloidal nature, as well as by a solids content of about 10 to 40% by weight and a RVF Brookfield bulk viscosity of up to 20,000 centipoises at 25.degree. C. and 20 RPM, are prepared by polymerizing 10-30 mole % of a cationic monomer, 5-30 mole % of an anionic monomer, 15-35 mole % of a hydrophobic monomer, and 5-70 mole % of a non-ionic hydrophilic monomer. The monomer amounts are selected so as to provide a copolymer having a charge density of about 15 to 60 mole % and charge ratio of between about 0.33 and 6. The polymerization is carried out without the use of solvents. The performance of the latices as pigment retention and drainage aids is unexpectedly good.
    Type: Grant
    Filed: August 21, 1980
    Date of Patent: December 15, 1981
    Assignee: National Starch and Chemical Corporation
    Inventors: Carmine P. Iovine, Dilip K. Ray-Chaudhuri
  • Patent number: 4284572
    Abstract: Copolymerizable blocked isocyanate diols are prepared by reacting a blocking agent with an isocyanate group of an organic diisocyanate under controlled conditions, thereby forming a blocked isocyanate group, and reacting the second isocyanate group in a subsequent step with the amine portion of a selected amine diol under anhydrous conditions. The resultant products are used to prepare self-crosslinkable, linear polyurethanes of high molecular weight.
    Type: Grant
    Filed: December 15, 1978
    Date of Patent: August 18, 1981
    Assignee: National Starch and Chemical Corporation
    Inventors: Henry Stanley, Dilip K. Ray-Chaudhuri
  • Patent number: 4268656
    Abstract: A N-substituted piperazine or N-substituted homopiperazine adduct with a polyepoxide is used as a co-curing agent in epoxy resin systems containing a polyepoxide and a known curing agent such as dicyandiamide, a carboxylic acid anhydride, or a dihydrazide. The preferred adducts have a ratio of epoxy groups to secondary amino groups of between 1.2:1 and 3:1. The preferred polyepoxides are polyglycidyl ethers of 4,4'-isopropylidenediphenol (bisphenol A). Suitable adducts are prepared from N-methyl-, N-(2-hydroxyethyl)-, N-octyl-, N-phenyl- and N-benzyl piperazine and N-methyl homopiperazine.
    Type: Grant
    Filed: January 16, 1980
    Date of Patent: May 19, 1981
    Assignee: National Starch and Chemical Corporation
    Inventors: Dilip K. Ray-Chaudhuri, Wen B. Chiao, Jules E. Schoenberg
  • Patent number: 4242488
    Abstract: A modified polyurethane adhesive composition characterized by its improved viscosity and high initial bond strength contains an isocyanate-terminated prepolymer or a fully reacted polyurethane and a carbamate ester which is compatible and not reactive with the prepolymer or polyurethane. The resultant adhesive is suitable for laminating many types of substrates. In a preferred embodiment the prepolymer is employed with the carbamate ester in a reactive hot-melt adhesive for use in bonding flexible substrates.
    Type: Grant
    Filed: May 9, 1979
    Date of Patent: December 30, 1980
    Assignee: National Starch and Chemical Corporation
    Inventors: Henry Stanley, Dilip K. Ray-Chaudhuri