Gold Bond Building Products, LLC

National Gypsum Properties, LLC

Basf Se Corporation

Basf Corporation

Malcam Ltd.

Eli Stav

Joseph J Bailey

R G Iyer

Ma-Ikay Miatudila

Karen Fey

Richard P Weir

Gopalakrisnan Sethuraman

Bradley J Busche

Brian G Randall

William C Martin

Sridhar Gopalkrishnan Iyer

David T Durocher

Richard J Romanek

Maryn L Heermann

Bradley G Busche

Veda Evans

Ronald A Lee

Brad Busche

Jie Ling

Matthew J Plante

Danny S Moshe

Gopalakrishnan Sethuraman

Gene Whittington

Craig Robertson

Elizabeth Burgess

Maryn Heermann

Susan Wiggins

The present invention is directed to an improved gypsum board, such as an improved sound damping gypsum board, and a method of making such gypsum board. For instance, the method comprises: providing a first encasing layer and a first sound damping layer on the first encasing layer wherein the sound damping layer includes at least 50 wt. % of a first sound damping polymer; depositing a gypsum slurry comprising stucco and water on the sound damping layer to form a gypsum core; providing a second encasing layer on the gypsum slurry; and allowing the stucco to convert to calcium sulfate dihydrate.

Sound damping gypsum board and method of constructing a sound damping gypsum board

The present invention is directed to an improved gypsum board, such as an improved sound damping gypsum board. The gypsum board comprises a gypsum core including gypsum and a sound damping polymer. The gypsum core includes a first gypsum layer surface and a second gypsum layer surface opposing the first gypsum layer surface. In addition, a first encasing layer is disposed on the first gypsum layer surface and a second encasing layer is disposed on the second gypsum layer surface.

Provided are cementitious panel that include a swellable material within a core layer, a dense layer, and/or a sheet of facing material that make up a cementitious panel, as well as methods of manufacturing such cementitious panels that include a swellable material and methods of providing a moisture or water barrier in a cementitious panel.

Cementitious panels with swellable materials and methods of providing a moisture or water barrier in cementitious panels using swellable materials

The present invention is directed to a gypsum board and a method of making such gypsum board. For instance, the gypsum board comprises a gypsum core, a first facing material, and a second facing material wherein the first facing material and the second facing material sandwich the gypsum core. The gypsum core comprises a first gypsum core section and a second gypsum core section each comprising gypsum, wherein the first gypsum core section comprises a polyol compound and has a density higher than a density of the second gypsum core section.

Gypsum board containing a polyol compound

Gypsum board having improved performance is obtained by controlling the distribution of starch in the gypsum core of the board and the gelling temperature of the starch. Starch migration in the board is controlled by the degree of acid-modification, to adjust the starch viscosity profile. The starch gelling temperature is controlled by chemical modification of the starch —OH groups.

Gypsum board with improved starch binder

The present disclosure is directed to a method of manufacturing gypsum board as well as the resulting gypsum board. The method comprises providing a gypsum slurry with a shrinkage-reducing additive comprising a metal salt of an acid, a silica, or a mixture thereof. As a result, the gypsum board includes gypsum and a shrinkage-reducing additive comprising a metal salt of an acid, a silica, or a mixture thereof. The gypsum board exhibits an area shrinkage of less than 10%.

Method of manufacturing gypsum board with improved fire resistance

The present invention is directed to a method of determining a free moisture content and/or a degree of calcination of a gypsum panel. The method comprises the following: (a) transmitting a microwave beam through at least a first portion of the gypsum panel, such that said microwave beam is a transmitted microwave beam; (b) receiving the transmitted microwave beam to form a received microwave beam; (c) determining a phase shift and an attenuation from the received microwave beam; (d) repeating steps (a) to (c) for at least a second portion of the gypsum panel, such that a plurality of phase shifts and a plurality of attenuations is obtained; (e) using at least one empirical factor to correct the plurality of attenuations, producing a plurality of corrected attenuations; (f) calculating a raw moisture content of the gypsum panel from the corrected attenuations wherein the raw moisture content comprises a raw free moisture content and a raw crystal moisture content; (g) using a calibration factor to correct the plurality of phase shifts, producing a plurality of corrected phase shifts; (h) determining a density of the gypsum panel from the corrected phase shifts; and (i) calculating a final moisture content of the gypsum panel from the density and from the raw moisture content wherein the final moisture content comprises a final free moisture content and a final crystal moisture content.

Inline detection of gypsum panel calcination

In general, the present invention is directed to the use of particular phosphorus containing compounds for making a gypsum board. The phosphorus containing compound may be a phosphite or a phosphate having a certain formula. In this regard, the present invention is directed to a slurry for making a gypsum board wherein the slurry includes such phosphorus containing compound. The present invention is also directed to a method of making a gypsum board from the slurry as well as a resulting gypsum board.

Gypsum board and gypsum slurry formed using a phosphorus containing compound

A slurry for manufacturing gypsum board is disclosed. The slurry comprises calcined gypsum, water, a foaming agent, and a thickening agent. The thickening agent of the present disclosure acts to improve the cohesiveness of the slurry without adversely affecting the setting time of the slurry, the paper-to-core bond (wet and dry), or the head of the slurry by acting as a defoaming agent or coalescing agent. Examples of suitable thickening agents include cellulose ether and co-polymers containing varying degrees of polyacrylamide and acrylic acid. A gypsum board and method of forming the slurry and the gypsum board are also disclosed. The gypsum board comprises a gypsum layer formed from the slurry.

Gypsum wallboard slurry and method for making the same

Gypsum board having improved performance is obtained by controlling the distribution of starch in the gypsum core of the board and the gelling temperature of the starch. Starch migration in the board is controlled by the degree of acid-modification, to adjust the starch viscosity profile. The starch gelling temperature is controlled by chemical modification of the starch &#x2014;OH groups.

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Charlotte, NC, United States of America

Eli Stav