Patents by Inventor Paul L. K. Hung

Paul L. K. Hung 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: 5554785
    Abstract: Esters of acrylic and methacrylic acid with alcohols and polyols having levels of purity greater than about 95% as measured by gas chromatography using an 11 meter RT.times.200 trifluoropropylmethyl polysiloxane column, a flame ionization detector, an injection temperature of 200.degree. C., an initial column temperature of 90.degree. C. for two minutes, followed by heating to 270.degree. C. at a rate of 8.degree. C. per minute and a detector temperature of 300.degree. C.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: September 10, 1996
    Assignee: CPS Chemical Company, Inc.
    Inventors: Louise E. Trapasso, Stanley J. Padegimas, Peter F. Epstein, Paul L. K. Hung, Purnendu Mukhopadhyay, Philip L. Meisel
  • Patent number: 5498751
    Abstract: Esters of monocarboxylic acids are transesterified with 1,2- and 1,3-polyols by reaction in the presence of a catalytically effective amount of a dialkyltin oxide blended with an excess of dialkyltin dichloride, so that a polyol ester of the monocarboxylic acid is formed. A transesterification reaction of alcohols and polyols with methyl or ethyl mono- or polycarboxylic acid esters utilizing a dimethyltin catalyst is also disclosed, in which the alcohol or polyol carboxylic acid ester formed is essentially free of the organotin catalyst. Carboxylic acid esters produced by the described methods, as well as carboxylic acid esters that are free of organotin catalysts are also disclosed.
    Type: Grant
    Filed: September 3, 1993
    Date of Patent: March 12, 1996
    Assignee: CPS Chemical Company, Inc.
    Inventors: Louis E. Trapasso, Stanley J. Padegimas, Peter F. Epstein, Paul L. K. Hung, Purnendu Mukhopadhyay, Philip L. Meisel
  • Patent number: 5148765
    Abstract: An improvement in the preparation of printed circuits comprises inserting a deformable layer between the phototool or support layer, and the solder mask. The deformable layer provides a uniform, integral and relatively thin coating of solder mask over circuit components, and results in higher-quality solder joints and lower rejection rates for finished boards.
    Type: Grant
    Filed: February 22, 1990
    Date of Patent: September 22, 1992
    Assignee: Elf Atochem North America, Inc.
    Inventors: Paul L. K. Hung, John Cioffi, Mark L. Lavach
  • Patent number: 5100946
    Abstract: The present invention comprises a stabilized halogen containing polymer, preferably poly(vinyl halide), and more preferably poly(vinyl chloride) composition. A preferred polymer composition is a rigid halogenated polymer such as rigid poly(vinyl chloride). The composition contains at least one metal salt selected from the group consisting of at least one carboxylic acid or derivative thereof having at least two carboxyl groups, at least one carboxyl group and at least one hydroxyl group, at least one carboxyl group and at least one mercaptan, and an aromatic carboxylic acid having at least one carboxyl group. The metal salt is most preferably disodium adipate.
    Type: Grant
    Filed: December 27, 1990
    Date of Patent: March 31, 1992
    Assignee: Atochem North America, Inc.
    Inventors: Paul L. K. Hung, William L. Smith, Daniel B. Dess, Sriram Seshadri
  • Patent number: 5006436
    Abstract: A UV curable, aqueous alkaline developable solder mask composition having tenting capabilities includes a thermal free radical initiator capable of generating free radicals with heat, and a polyunsaturated compound capable of being thermally cross-linked by the free radicals to provide a substantially fully cured solder mask coating.
    Type: Grant
    Filed: September 20, 1988
    Date of Patent: April 9, 1991
    Assignee: Atochem North America, Inc.
    Inventors: Paul L. K. Hung, Kenneth K. S. Tseng
  • Patent number: 4874799
    Abstract: Aqueous alkaline developable, UV curable urethane acrylate compounds and compositions are particularly useful for making flexible, 100% solids, solvent-free solder mask coatings which are characterized by having screen-printable viscosities, rapid developability and advantageous performance characteristics.
    Type: Grant
    Filed: July 10, 1987
    Date of Patent: October 17, 1989
    Assignee: M&T Chemicals Inc.
    Inventors: Paul L. K. Hung, Kenneth K. S. Tseng
  • Patent number: 4761363
    Abstract: A composition including a mixture of UV curable urethane acrylate and a urethane diacrylate compounds provides an aqueous alkaline developable, flexible solder mask having excellent electrical insulation resistance under hydrolytic testing conditions at elevated temperatures.
    Type: Grant
    Filed: April 18, 1986
    Date of Patent: August 2, 1988
    Assignee: M&T Chemicals Inc.
    Inventors: Paul L. K. Hung, Kenneth K. S. Tseng
  • Patent number: 4753860
    Abstract: A composition including a mixture of UV curable urethane acrylate and a urethane diacrylate compounds provides an aqueous alkaline developable, flexible solder mask having excellent electrical insulation resistance under hydrolytic testing conditions at elevated temperatures.
    Type: Grant
    Filed: June 20, 1985
    Date of Patent: June 28, 1988
    Assignee: M&T Chemicals Inc.
    Inventors: Paul L. K. Hung, Kenneth K. S. Tseng
  • Patent number: 4717740
    Abstract: An aqueous alkaline developable UV curable urethane acrylate compound and composition are used for making flexible solder mask coatings, characterized by rapid development in an aqueous, alkaline medium, and advantageous performance properties.
    Type: Grant
    Filed: May 17, 1985
    Date of Patent: January 5, 1988
    Assignee: M&T Chemicals Inc.
    Inventors: Paul L. K. Hung, Kenneth K. S. Tseng
  • Patent number: 4713298
    Abstract: A printed circuit board having improved adhesion between solder mask and metal includes a primer film on the metal deposited from an aqueous solution which includes 0.01 to 10% by weight of a carboxyl-containing polymer or copolymer.
    Type: Grant
    Filed: April 17, 1986
    Date of Patent: December 15, 1987
    Assignee: M&T Chemicals Inc.
    Inventors: Paul L. K. Hung, Richard J. Radigan, David S. Rosen
  • Patent number: 4615950
    Abstract: A printed circuit board having improved adhesion between solder mask and metal includes a primer film on the metal deposited from an aqueous solution which includes 0.01 to 10% by weight of a carboxyl-containing polymer or copolymer.
    Type: Grant
    Filed: March 15, 1985
    Date of Patent: October 7, 1986
    Assignee: M&T Chemicals Inc.
    Inventors: Paul L. K. Hung, Richard J. Radigan, David S. Rosen
  • Patent number: 4614704
    Abstract: A method and composition for increasing the cure depth of a solder mask coating at a low UV energy level. The stable composition, which includes a UV curable compound and a photoinitiator, is characterized by the presence of triphenylphosphite in the composition.
    Type: Grant
    Filed: June 21, 1985
    Date of Patent: September 30, 1986
    Assignee: M&T Chemicals Inc.
    Inventors: Paul L. K. Hung, Mark L. Lavach