Patents by Inventor Donald L. Roelfs

Donald L. Roelfs 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: 8568544
    Abstract: A fibrous mat-faced cementitious article comprising (a) a cementitious core, and (b) a first fibrous mat comprising polymer or mineral fibers and a hydrophobic finish on at least one surface thereof, wherein the hydrophobic finish is in contact with the cementitious core, and a method of preparing a fibrous mat-faced cementitious article, as well as a method of preparing a water-resistant cementitious article comprising (a) preparing an aqueous siloxane dispersion, wherein the dispersion comprises about 4 wt. % to about 8 wt. % siloxane, (b) combining the siloxane dispersion with a cementitious mixture to provide a cementitious slurry, (c) depositing the cementitious slurry onto a substrate, and (d) allowing the cementitious slurry to harden, thereby providing a cementitious article.
    Type: Grant
    Filed: October 28, 2011
    Date of Patent: October 29, 2013
    Assignee: United States Gypsum Company
    Inventors: Dick C. Engbrecht, Qingxia Liu, Michael P. Shake, Xuming Wang, David Paul Miller, Michael L. Bolind, Paul Reed, Donald L. Roelfs, Rafael Bury
  • Publication number: 20120040168
    Abstract: A fibrous mat-faced cementitious article comprising (a) a cementitious core, and (b) a first fibrous mat comprising polymer or mineral fibers and a hydrophobic finish on at least one surface thereof, wherein the hydrophobic finish is in contact with the cementitious core, and a method of preparing a fibrous mat-faced cementitious article, as well as a method of preparing a water-resistant cementitious article comprising (a) preparing an aqueous siloxane dispersion, wherein the dispersion comprises about 4 wt. % to about 8 wt. % siloxane, (b) combining the siloxane dispersion with a cementitious mixture to provide a cementitious slurry, (c) depositing the cementitious slurry onto a substrate, and (d) allowing the cementitious slurry to harden, thereby providing a cementitious article.
    Type: Application
    Filed: October 28, 2011
    Publication date: February 16, 2012
    Applicant: UNITED STATES GYPSUM COMPANY
    Inventors: Dick C. ENGBRECHT, Qingxia LIU, Michael P. SHAKE, Xuming WANG, David Paul MILLER, Michael L. BOLIND, Paul REED, Donald L. ROELFS, Rafael BURY
  • Patent number: 8070895
    Abstract: A fibrous mat-faced cementitious article comprising (a) a cementitious core, and (b) a first fibrous mat comprising polymer or mineral fibers and a hydrophobic finish on at least one surface thereof, wherein the hydrophobic finish is in contact with the cementitious core, and a method of preparing a fibrous mat-faced cementitious article, as well as a method of preparing a water-resistant cementitious article comprising (a) preparing an aqueous siloxane dispersion, wherein the dispersion comprises about 4 wt. % to about 8 wt. % siloxane, (b) combining the siloxane dispersion with a cementitious mixture to provide a cementitious slurry, (c) depositing the cementitious slurry onto a substrate, and (d) allowing the cementitious slurry to harden, thereby providing a cementitious article.
    Type: Grant
    Filed: April 20, 2007
    Date of Patent: December 6, 2011
    Assignee: United States Gypsum Company
    Inventors: Dick C. Engbrecht, Qingxia Liu, Michael P. Shake, Xuming Wang, David Paul Miller, Michael L. Bolind, Paul Reed, Donald L. Roelfs, Rafael Bury
  • Publication number: 20100143682
    Abstract: A cementitious composite article comprising (a) a cementitious core, (b) a skim coat cementitious layer in contact with the cementitious core having a density greater than the cementitious core, and (c) a fibrous mat comprising (i) microfibers and (ii) continuous fibers having a length of about 0.6 cm or more, wherein the fibrous mat comprises an inner surface in contact with the skim coat cementitious layer; as well as a method for manufacturing same.
    Type: Application
    Filed: October 29, 2009
    Publication date: June 10, 2010
    Applicant: United States Gypsum Company
    Inventors: Michael P. SHAKE, Qingxia LIU, Salvatore C. IMMORDINO, Dick C. ENGBRECHT, Donald L. ROELFS, Christopher R. NELSON, Wayne J. ROHRBAUGH, Joseph J. FEDORIS
  • Publication number: 20090029141
    Abstract: A mat-faced gypsum board and method of making thereof is provided having a particulate matter applied on an inner surface of the facer mat and extending partially into the mat from the inner surface thereof. The particulate matter, which is preferably a hydratable powder such as calcium sulfate hemihydrate, minimizes and, preferably, prevents bleed through of a gypsum slurry during formation of the gypsum board.
    Type: Application
    Filed: July 18, 2008
    Publication date: January 29, 2009
    Applicant: UNITED STATES GYPSUM COMPANY
    Inventors: Michael P. SHAKE, Qingxia LIU, Salvatore C. IMMORDINO, Dick C. ENGBRECHT, Donald L. ROELFS, Christopher R. NELSON, Wayne J. ROHRBAUGH, Joseph J. FEDORIS
  • Publication number: 20080190062
    Abstract: A fibrous mat-faced cementitious article comprising (a) a cementitious core, and (b) a first fibrous mat comprising polymer or mineral fibers and a hydrophobic finish on at least one surface thereof, wherein the hydrophobic finish is in contact with the cementitious core, and a method of preparing a fibrous mat-faced cementitious article, as well as a method of preparing a water-resistant cementitious article comprising (a) preparing an aqueous siloxane dispersion, wherein the dispersion comprises about 4 wt. % to about 8 wt. % siloxane, (b) combining the siloxane dispersion with a cementitious mixture to provide a cementitious slurry, (c) depositing the cementitious slurry onto a substrate, and (d) allowing the cementitious slurry to harden, thereby providing a cementitious article.
    Type: Application
    Filed: April 20, 2007
    Publication date: August 14, 2008
    Applicant: United States Gypsum Company
    Inventors: Dick C. Engbrecht, Qingxia Liu, Michael P. Shake, Xuming Wang, David Paul Miller, Michael L. Bolind, Paul Reed, Donald L. Roelfs, Rafael Bury