Patents by Inventor Ding Y. Chung

Ding Y. Chung 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: 5472998
    Abstract: An improved aqueous cathodic electrocoating composition having a binder of an epoxy-amine adduct which is of an epoxy resin that has been reacted with an amine, and a blocked polyisocyanate crosslinking agent; wherein the improvement is the use of a water soluble electrically conductive polymeric additive of a polyepoxy hydroxy ether resin reacted with a ketimine and optionally up to 60% of the epoxy end groups of the resin reacted with another amine and the resin has an epoxy equivalent weight of about 500-900, a weight average molecular weight of about 1,000-5,000 and an electrical conductivity of about 4,000-8,000 microsiemens to provide an electrocoating composition having improved throw power.
    Type: Grant
    Filed: September 16, 1994
    Date of Patent: December 5, 1995
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: Robert A. Tessmer, Peter W. Uhlianuk, Ding Y. Chung
  • Patent number: 5416137
    Abstract: An improved aqueous cathodic electrocoating composition having a binder of an epoxy resin-amine adduct which is an epoxy resin that has been reacted with an amine, and a blocked polyisocyanate crosslinking agent; wherein the improvement is the use of a multihydric phenol i.e., a phenol having more than two reactive hydroxyl groups along with a dihydric phenol to form the epoxy resin used in the electrocoating composition to provide a composition having improved throw power.
    Type: Grant
    Filed: June 1, 1994
    Date of Patent: May 16, 1995
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: Lee A. Turnquist, Peter W. Uhlianuk, Ding Y. Chung
  • Patent number: 5382607
    Abstract: An improved aqueous electrocoating composition having a binder of an epoxy-amine adduct and a blocked polyisocyanate crosslinking agent; wherein the improvement is the use of zinc hydroxyphosphite pigment as a corrosion inhibitive pigment and an as a curing catalyst which provides an excellent cure under overbake and underbake conditions and forms a coating with excellent chip resistance and the throwing power of the electrocoating composition is significantly improved.
    Type: Grant
    Filed: October 7, 1993
    Date of Patent: January 17, 1995
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: Robert J. Sikora, Allisa Gam, Ding Y. Chung
  • Patent number: 5356960
    Abstract: An improved aqueous electrocoating composition that contains an anticrater agent which is a reaction product of poly epoxy hydroxy ether resin, polyoxyalkylene diamine and an amino, glycidyl or isocyanate functional alkyl alkoxy silane having a number average molecular weight of about 1,000-6,000; electrodeposited finishes are formed that have a significant reduction in craters and are smooth and even finishes.
    Type: Grant
    Filed: August 11, 1993
    Date of Patent: October 18, 1994
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: Ding Y. Chung, Allisa Gam
  • Patent number: 5314594
    Abstract: An improved aqueous electrocoating composition having a binder of an epoxy-amine adduct and a blocked polyisocyanate crosslinking agent; wherein the improvement is the use of an effective amount of an additive of an alkyl thioester or a polymeric product of an epoxy resin, polyalkylene glycol and a sugar to form an electrocoating composition that has significantly improved throwing power and provides a coating that has the necessary properties such as chip, solvent and corrosion resistance.
    Type: Grant
    Filed: December 9, 1992
    Date of Patent: May 24, 1994
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: Ding Y. Chung, Kenneth S. Kirshenbaum
  • Patent number: 5281316
    Abstract: An improved aqueous electrocoating composition having a binder of an epoxy-amine adduct and a blocked polyisocyanate crosslinking agent; wherein the improvement is the use of an effective amount of a blend of a zinc containing compound and a lead pigment to form an electrocoating composition that has significantly improved throwing power and provides a coating that has the necessary properties such as chip, solvent and corrosion resistance.
    Type: Grant
    Filed: May 29, 1992
    Date of Patent: January 25, 1994
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: Ding Y. Chung, Robert J. Sikora, John J. Vincent
  • Patent number: 5205916
    Abstract: An improved aqueous electrocoating composition having a binder of an epoxy-amine adduct and a blocked polyisocyanate crosslinking agent; wherein the improvement is the use of an antioxidant additive which is a combination of a phenolic antioxidant and a sulfur-containing antioxidant. The additive reduces overbake yellowing of the composition and the intercoat delamination of the composition and the topcoat upon exterior exposure.
    Type: Grant
    Filed: December 11, 1991
    Date of Patent: April 27, 1993
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: Ding Y. Chung, Kenneth S. Kirshenbaum
  • Patent number: 5185065
    Abstract: An electrocoating composition containing an epoxy amine adduct which is the reaction product of a polyepoxide resin and an amine, an acrylic amine resin and a blocked polyisocyanate crosslinking agent;wherein the composition is prepared by blending a first emulsion of the epoxy amine adduct and the blocked polyisocyanate crosslinking agent with a second emulsion of the acrylic amine resin and a blocked polyisocyanate crosslinking agent; where the first and second emulsions are each individually formed by blending the adduct or resin with the blocked crosslinking agent and then adding an organic acid to form a salt which forms a stable aqueous emulsion.
    Type: Grant
    Filed: August 1, 1991
    Date of Patent: February 9, 1993
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: Ding Y. Chung, Allisa Gam, Robert A. Tessmer
  • Patent number: 5145568
    Abstract: An electrodepositable cationic electrocoating bath containing a nonaqueous pigment paste containing organic solvent. The use of an organic solvent in the place of an aqueous solvent minimizes or eliminates foaming in the process of making the pigment paste.
    Type: Grant
    Filed: December 18, 1990
    Date of Patent: September 8, 1992
    Assignee: E. I. du Pont de Nemours and Company
    Inventors: Ding Y. Chung, Tapan K. Debroy, Sioe-Heng A. Tjoe
  • Patent number: 5116914
    Abstract: An improved aqueous electrocoating composition that contains a catalyst for a curing the components of the electocoating composition of a blocked polyisocyanate and an epoxy amine adduct, wherein the catalyst is alkyl tin diacetyl acetonate, preferably, dibutol tin diacetyl acetonate.
    Type: Grant
    Filed: December 18, 1990
    Date of Patent: May 26, 1992
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: Ding Y. Chung, Tapan K. Debroy
  • Patent number: 5108575
    Abstract: Disclosed herein is a cathodic electrodepositable resin containing polyamine enamine. It has been discovered that reacting epoxy resins with polyamine enamine is a viable method of introducing amine functionality to the epoxy resin. The polyamine enamine route results in the desired high pH and stable dispersion in the electrocoat bath.
    Type: Grant
    Filed: August 8, 1990
    Date of Patent: April 28, 1992
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: Ding Y. Chung, Tapan K. Debroy
  • Patent number: 5095051
    Abstract: An improved electrodepositable cationic resin is disclosed. Prior art electrodepositable cationic resins are formed from polyepoxides which are chain extended with polyether or polyester polyols to internally flexibilize the resin. Our polyepoxide resin is chain extended with amide diol which gives a resin which is hydrolytically stable and does not tend to absorb moisture.
    Type: Grant
    Filed: August 6, 1990
    Date of Patent: March 10, 1992
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: Ding Y. Chung, Tapan K. Debroy, Robert A. Tessmer
  • Patent number: 5089100
    Abstract: Disclosed herein is a method of incorporating amine functionality onto a polyepoxy resin to be used for cathodic electrocoat. This method has the following steps:a) reacting an epoxy resin with an amount of secondary amine so that unreacted epoxy functional groups remain; andb) further reacting the reaction product of a) with a polyamine so that there is a minimum of one equivalent of epoxy for every mole of polyamine. This method results in an electrocoat bath with the desired high pH and a stable dispersion.
    Type: Grant
    Filed: August 6, 1990
    Date of Patent: February 18, 1992
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: / Tapan K. Debroy, Ding Y. Chung
  • Patent number: 5074978
    Abstract: What is disclosed are electrodepositable cationic baths containing low molecular weight hydroxyl terminated polyester adhesion promotion additives. These low molecular weight hydroxyl terminated polyesters have been found to improve chip resistance, adhesion and film build.
    Type: Grant
    Filed: February 23, 1990
    Date of Patent: December 24, 1991
    Assignee: E. I. du Pont de Nemours and Company
    Inventors: Tapan K. Debroy, Ding Y. Chung, Craig R. Deschner
  • Patent number: 5070149
    Abstract: A novel cationic electrodepositable resin which offers reduced bake off lose, reduced yellowing of topcoats and very smooth film is disclosed. The backbone resin contains the basic polyepoxy amine adduct but it is crosslinked with a diol modified methylene diphenyl diisocyanate (MDI) which is blocked with a mixture of various alcohols.
    Type: Grant
    Filed: April 9, 1990
    Date of Patent: December 3, 1991
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: Tapan K. DeBroy, Ding Y. Chung
  • Patent number: 5066688
    Abstract: An improved aqueous electrocoating composition that contains a reactive additive of the following formula ##STR1## wherein R is an aliphatic hydrocarbon group; finishes formed from the composition have improved cure and chip resistance.
    Type: Grant
    Filed: April 10, 1991
    Date of Patent: November 19, 1991
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: Ding Y. Chung, Tapan K. Debroy, Sioe-Heng A. Tjoe
  • Patent number: 5057558
    Abstract: An improved electrodepositable cationic resin is disclosed. Prior art electrodepositable cationic resins are formed from polyepoxides which are chain extended with polyether or polyester polyols to internally flexibilize the resin. The polyepoxide resin of the invention is chain extended with a monoepoxide-triol adduct which provides a resin with improved throw power and improved flow while maintaining other important characteristics of the resin.
    Type: Grant
    Filed: November 27, 1990
    Date of Patent: October 15, 1991
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: Ding Y. Chung, Tapan K. Debroy
  • Patent number: 5049249
    Abstract: A low temperature cure electrodepositable cathodic resin is disclosed. The resin is the reaction product of a polyepoxide amine adduct and a novel blocked crosslinking agent. The crosslinking agent of our invention is tetramethylxylene diisocyanate blocked with any suitable blocking agent. The resulting resin can be cured at relatively low temperatures (250.degree.-275.degree. F.), which potentially allows the use of the resin with articles containing plastics.
    Type: Grant
    Filed: August 30, 1989
    Date of Patent: September 17, 1991
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: Ding Y. Chung, Tapan K. DebRoy
  • Patent number: 5035785
    Abstract: Disclosed herein are electrodepositable cationic baths containing nonionic pigment dispersants. These nonionic pigment dispersants are ethoxylated styrenated phenols which allow for increased production capacity and lower VOC. The ethoxylated styrenated phenols are also used as an additive which can increase film build and improve film smoothness.
    Type: Grant
    Filed: February 23, 1990
    Date of Patent: July 30, 1991
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: Tapan K. Debroy, Ding Y. Chung, Sioe-Heng A. Tjoe, Craig R. Deschner
  • Patent number: 4994507
    Abstract: Disclosed herein are cathodic electrodepositable coating baths containing lead cyanamide as a supplementary catalyst. It has been found that using lead cyanamide in conjunction with a primary metal catalyst (e.g. dibutyltin oxide) results in an electrocoat system with superior underbake cure without sacrificing chipping characteristics during overbake cure.
    Type: Grant
    Filed: February 20, 1990
    Date of Patent: February 19, 1991
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: Tapan K. Debroy, Ding Y. Chung, Craig R. Deschner, Sioe-Heng A. Tjoe