Patents by Inventor Malcolm J. Welch

Malcolm J. Welch 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: 6165320
    Abstract: This invention relates to a method of sizing paper comprising use of a sizing composition comprising: (a) at least one thermoplastic resin selected from the group consisting of thermoplastic rosins having an acid number less than 50, thermoplastic hydrocarbon resins, thermoplastic polyamides and thermoplastic amide waxes; (b) starch; and (c) surfactant. The sizing takes place substantially in the absence of alum or other aluminum based fixing agents.
    Type: Grant
    Filed: June 28, 1999
    Date of Patent: December 26, 2000
    Assignee: Hercules Incorporated
    Inventors: Robert Bates, Gerard J. Broekhuisen, Edwin R. Hensema, Malcolm J. Welch
  • Patent number: 6074468
    Abstract: This invention relates to a sizing composition comprising (a) thermoplastic resin selected from the group consisting of thermoplastic rosins having an acid number less than 50, thermoplastic hydrocarbon resins, thermoplastic polyamides and thermoplastic amide waxes; (b) starch selected from the group consisting of natural, anionic, oxidized, amphoteric and modified starch; and (c) surfactant.
    Type: Grant
    Filed: June 23, 1999
    Date of Patent: June 13, 2000
    Assignee: Hercules Incorporated
    Inventors: Robert Bates, Gerard J. Broekhuisen, Edwin R. Hensema, Malcolm J. Welch
  • Patent number: 5972094
    Abstract: This invention relates to a sizing composition comprising a thermoplastic resin selected from the group consisting of thermoplastic rosins having an acid number less than 50, thermoplastic hydrocarbon resins, thermoplastic polyamides and thermoplastic amide waxes, its use in sizing paper and paper sized with the sizing agent. The invention also relates to a method of sizing paper comprising use of a composition comprising a thermoplastic rosin, wherein the sizing takes place substantially in the absence of alum, and paper so sized.
    Type: Grant
    Filed: May 22, 1997
    Date of Patent: October 26, 1999
    Assignee: Hercules Incorporated
    Inventors: Robert Bates, Gerard J. Broekhuisen, Edwin R. Hensema, Malcolm J. Welch
  • Patent number: 5912306
    Abstract: This invention generally provides a class of novel cationic resin comprised of a cross-linked polyamine having pendant tertiary and/or quaternary amine groups linked to amine groups in said polyamine by a hydrocarbon chain including a hydroxyl group in the .beta.-position with respect to the polyamine chain. In general, these resins can comprise the reaction product of a polyamine having secondary amine groups, a crosslinking agent, and a cationizing agent having an epoxide group and a tertiary or quaternary amine (quaternary ammonium) group. These cationic resins have been found to be useful for a variety of operations in the manufacture of paper and paperboard, especially as drainage aids and stabilizers for dispersed rosin sizing agents.
    Type: Grant
    Filed: November 22, 1996
    Date of Patent: June 15, 1999
    Assignee: Hercules Incorporated
    Inventors: Ian A. Pudney, Brian M. Stubbs, Malcolm J. Welch
  • Patent number: 5393338
    Abstract: This invention generally provides a class of novel cationic resin comprised of a cross-linked polyamine having pendant tertiary and/or quaternary amine groups linked to amine groups in said polyamine by a hydrocarbon chain including a hydroxyl group in the .beta.-position with respect to the polyamine chain. In general, these resins can comprise the reaction product of a polyamine having secondary amine groups, a crosslinking agent, and a cationizing agent having an epoxide group and a tertiary or quaternary amine (quaternary ammonium) group. These cationic resins have been found to be useful for a variety of operations in the manufacture of paper and paperboard, especially as drainage aids and stabilizers for dispersed rosin sizing agents.
    Type: Grant
    Filed: December 30, 1992
    Date of Patent: February 28, 1995
    Assignee: Hercules Incorporated
    Inventors: Ian A. Pudney, Brian M. Stubbs, Malcolm J. Welch